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BACKGROUND OF THE INVENTION
The invention relates to a process for the reattachment of a thread in an open-end spinning machine having at least one spinning motor. For this purpose, a thread is introduced into the rotating spinning rotor where it attaches itself to a ring of fibers located in the fiber collection groove of the spinning rotor. Subsequently, the thread is drawn out of the spinning rotor and is wound up on a driven windup spindle. A pair of drawoff rollers is provided between the spinning rotor and the windup spindle. The invention further relates to an apparatus for carrying out this process.
When it is intended to attach, i.e., re-spin a thread, in an open-end spinning machine having spinning rotors, for example when a thread breakage has occurred, the end of the thread must be guided back from the spindle into the spinning rotor. There it is attached to the fiber ring located in the rotating spinning rotor. From the moment that the end of the thread combines with the fiber ring, the thread is twisted and can be continuously drawn off so that a new thread is continuously formed from fibers pulled out of the fiber collection groove. In known manner, the fibers are guided pneumatically and continuously to the fiber collection groove. It is important that, in each instance of a new re-spinning of a thread to the fibers located within the spinning rotor, the pullout of thread from the spinning rotor takes place at a point in time when the thread end combines with the fiber ring located in the spinning rotor, because otherwise, excessive twisting of the thread, i.e., imparting too many rotations per unit length, would break the thread and this would lead to a failure of the re-spinning process and a new re-spinning attempt would be required.
When the end of the thread fed into the spinning rotor for the purpose of re-spinning is dragged along and shares the rotation of the spinning rotor, it undergoes a sudden increase of tension and simultaneously, the end of the thread is twisted onto the fibers deposited in the fiber collection groove of the spinning rotor and the thread breakage is thereby relieved. According to the present invention, this increase of the tensile stress in the thread is used as a signal for beginning to draw the thread out of the spinning rotor.
It has been shown that the attachment, i.e., the re-spinning of threads onto spinning rotors which run at very high rpm, for example, at 60,000 rpm and higher, is very difficult. In such cases, if the drawoff of the thread does not begin immediately after the attachment, i.e., after twisting the thread onto the fiber ring, then the thread is twisted off and broken in a very short time and the re-spinning attempt must then be repeated. This can be easily understood if it is realized that when the rotor turns at 60,000 rpm, in only half a second it imparts 500 rotations to a stationary and already twisted piece of thread which has a length of only approximately 10 cm as between the fiber collection groove and the thread guiding members which prevent further twisting. This comes to approximately 5,000 twists per meter of thread length which would be sufficient to twist off and break even fine threads. On the other hand, if the thread is drawn off too early, i.e., before the end of the thread guided into the spinning rotor has been twisted onto the fiber ring located therein, the attachment process has effectively failed also.
The period of time which elapses between sensing the increase of the tensile force in the thread due to its sharing the rotation of the spinning rotor and the time when the thread is already twisted too much is too short for a purely manual re-spinning operation when rotor speeds of approximately 60,000 rpm are used, i.e., the time which is available to an operator for sensing the increase of the tensile force in a piece of thread guided into the rotor and for the initiation of the drawoff process of that thread is too short: the thread is twisted off and breaks before the operator can react to the increase of the tensile force and can initiate the drawoff of the thread. Therefore, until the present time, it has been necessary to reduce the operating speed of the machine when a thread was being reattached. However, this is cumbersome, requires a separate apparatus (German Offenlegungsschrift No. 2,314,473) and results in a reduction of the productive capacity of the machine.
OBJECT AND SUMMARY OF THE INVENTION
It is a principal object of the invention to provide a process which makes it possible to attach, i.e., re-spin threads in open-end spinning machines even at very high speeds of the spinning rotor.
This object is attained, according to the invention, by providing that while the thread to be re-spun is introduced into the spinning rotor, it is kept away from the contact line or pinch line of the draw roller pair by being held at the axial, or end face of a draw roller. In addition, means are provided for sensing the increase of the thread tension which is produced when the end of the thread introduced into the spinning rotor shares the motion of the rotating spinning rotor. It is further provided that, subsequent to sensing the increase of the thread tension, the windup spindle is rotated in the windup direction and that the thread tension between the spinning rotor and the windup spindle causes the thread to be guided to the pinch line between the driven pair of draw rollers. Hence, the thread introduced into the spinning rotor is drawn out as soon as the end of the thread has been twisted onto the fibers deposited in the spinning rotor. The fact that the thread is not drawn off sooner prevents thread attachment failures. On the other hand, the removal of thread is begun immediately after the thread has been twisted onto the fibers located in the spinning rotor, preventing excessive twisting and breakage of the thread. This doubly effective control of the point when drawoff of the thread is begun can be achieved by using and embodying according to the invention only elements which are either already present or only simple supplementary elements.
The apparatus for carrying out the process according to the invention includes a thread guide, located between the spinning rotor and the draw roller pair. This thread guide, the draw roller pair and the windup spindle are so disposed that a thread which is fed back from the windup spindle to the thread guide lies up against an end face of one of the draw rollers so that it is displaced with respect to its location in normal operation. The apparatus further includes means for sensing the increased thread tension due to the fact that the end of the thread is carried along with and shares the rotational motion of the spinning rotor, and it triggers the start of the windup spindle.
A preferred further development of the invention provides that the pinch line of the draw roller pair lies at a certain distance from the plane defined by the thread guide and the thread guiding surface of the displacement roller. This distance is such that the thread to be reattached which is guided back into the thread draw out channel associated with the spinning rotor but which has not yet been reattached lies at some distance from one of the draw rollers whereas it lies up against the end surface of the other draw roller.
A further advantageous embodiment of the invention provides that the rim of the pressure roller is conical at least in the region in which the thread lies. This arrangement assures in a simple manner that the thread cannot be damaged by touching or wrapping itself around sharp corners of the rim of the pressure roller. Furthermore, it facilitates the movement of the thread to the pinch line of the draw roller pair. As has already been mentioned above, the thread tension sensor causes the thread windup spindle to be started when it senses an increase of the thread tension due to the fact that the end of the thread delivered to the spinning rotor shares in the rotation thereof. This can be done, for example, by locking the windup spindle at first in a position such that it is lifted off from the drive roller embodied as a friction roller.
When a signal is received from the thread tension sensor, the lock is released, and the windup spindle is lowered onto the driving roller. In another embodiment, the drive means for the windup spindle can include a switching clutch which is actuatable by the thread tension sensor. The elements which guide the thread are to be so disposed that the thread which lies up against an end face of one of the draw rollers is not pulled into the pinch line of the pair of draw rollers under the influence of the slight tensile force due to the air stream flowing into the spinning chamber, i.e., into the spinning rotor, through the thread drawoff aperture in the spinning member. Rather, it is intended that this displacement occur only as a consequence of the greater tensile force in the thread which is produced when the end of the thread shares in the rotation of the spinning rotor.
The most important parameters which influence these effects are, among others, the magnitude of the two above-mentioned tensile forces in the thread, the degree of deviation of the thread when it lies against an end face of the rim, the position of the secant with which the thread lies up against the flange and whether the thread touches or does not touch the circumferential surface of one of the draw rollers. The position the members guiding the thread must have for achieving the desired effect can be determined with no difficulty by test arrangements made for each individual case. It has been shown to be particularly advantageous if the angle by which the thread is laterally deviated by attachment to an end face of one of the draw rollers is 10° to 45° and preferably 25° to 35°.
The invention will be better understood as well as further objects and advantages will become more apparent from the ensuing detailed specification of preferred although exemplary embodiments taken in conjunction with the drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of an exemplary embodiment of an apparatus for re-spinning a thread onto an open end spinning machine, in a front elevational view;
FIG. 2 is a side view of the apparatus according to FIG. 1 in the position it occupies after the occurrence of a thread breakage, when the windup spindle is lifted up and the end of the thread has already been guided back into the spinning box but has not yet been attached to the fiber ring within the spinning rotor; and
FIG. 3 is another embodiment of the draw roller pair of the apparatus according to FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 and 2 show a single spinning box 1 of an open-end spinning machine which is equipped with a plurality of spinning boxes of this type. The spinning box 1 may be of any known kind. In a typical embodiment, the spinning box 1 has a device for supplying and spreading the fibers which are delivered to the spinning rotor located within the spinning box and which are twisted and drawn out as a thread G at a predetermined drawoff rate from a thread exit aperture 2 within the spinning box 1. The thread exit aperture 2 can in general be the outlet termination of a thread drawoff channel which is either stationary or is connected to the spinning rotor and whose longitudinal axis coincides with the rotational axis of the spinning rotor.
The thread is drawn out by a pair of draw rollers consisting of a constantly driven draw roller 3 and a draw roller 4, pressed against it. One of the draw rollers (in the example shown it is the draw roller 4), has a free end face 4'. This draw roller 4 can be mounted at each end in bearings but may only have one bearing, i.e., may be mounted in "flying" manner. The end face 4' of the draw roller 4 is preferably frusto-conical. Each thread G is guided via one thread guide 6 and one thread tension sensor 7 disposed between the spinning box 1 and the draw roller pair 3,4. The thread guide 6 and the thread tension sensor 7 can be combined in one member as shown or may be disposed separately. From the drawoff roller pair 3,4, the thread G travels to a driven windup spindle and is wound up thereon. The windup spindle 10 rests on top of a customary, driven distribution roller 9, for example a grooved roller, and is driven thereby. The windup spindle 10 is rotatably mounted on a pivotable arm 12 and presses against the distribution roller 9 due to its own weight. The windup spindle 10 can be held in a position in which it is lifted off from the distribution roller 9 by an operable latch 13 which engages the arm 12. The latch 13 is actuated by the thread tension sensor 7 in such a way that the latch 13 is pulled back and, thus, the windup spindle 10 is lowered onto the distribution roller 9 whenever the thread tension, as sensed by the thread tension sensor, exceeds a predetermined and adjustable value. The actuation of the latch 13 can be preferably take place electrically through a line 8 by closure of a contact within the thread tension sensor 7, causing a current to flow through an electromagnet 14 which pulls back the latch 13.
The spatial association of the thread guide 6, the thread tension sensor 7, the draw rollers 3 and 4 as well as the distribution roller 9 is such that the thread G guided over these elements and lying up against the free end surface 4' of the draw roller 4 is deviated both at the thread tension sensor 7 as well as at the draw roller 4. The displacement at the thread tension sensor 7 tends to load the thread tension sensor and the displacement at the draw roller 4 tends to pull the thread between the draw rollers 3,4.
According to the disposition of FIG. 2, the draw rollers 3,4 are so located that the thread which runs in a straight line from the thread guide 6 to the distribution roller 9 is displaced from the center in a direction opposite to draw roller 3 and lies up against the end face 4' of the draw roller 4. FIG. 3 shows the draw rollers 3 and 4 so disposed that the thread G which has not yet been reattached lies up against the circumferential surface of the draw roller 3 as well as against the end face of the draw roller 4.
The re-spinning or reattachment of a thread will now be explained with the aid of FIGS. 1 and 2.
In the exemplary embodiment shown in these figures the wound-up thread package located on the windup spindle 10 has almost attained its final diameter because, even in the lifted-off position, the windup spindle is located at a relatively small distance from the distribution roller 9. However, the repair of a thread breakage can take place at any diameter of the thread winding package, even if the windup spindle 10 is still empty. In the latter case, a thread is wound around the windup spindle 10 several times so that it can no longer slide on the windup spindle 10. In both cases, the free end of the thread is guided, by hand or, if necessary, by automatic means, into the exit aperture 2 of the spinning box 1 for the purpose of re-spinning the thread. The thread is brought into the path seen in FIGS. 1 and 2, between the windup spindle 10 and the thread guide 6, where it lies up against the end face 4' of the draw roller 4 which is pressed against the driven draw roller 3, and thence passes through the thread guide 6 to the spinning box 1. In such a spinning box 1 of an open-end spinning machine, at least when the spinning rotor is turning, an air stream always flows from the outside into the thread drawoff channel and through it into the interior of the spinning rotor. Thus, it is sufficient, at least in most cases, to insert the thread end to be reattached into the thread drawoff channel of the spinning box or to bring it so near that it is carried along by the air stream flowing through the thread drawoff channel and is thereby introduced into the interior volume of the rotating spinning rotor. When the reattachment takes place, the fiber collection groove of the spinning rotor contains fibers. The fibers are introduced pneumatically, in known manner, through a fiber supply channel, to the interior volume of the spinning rotor. It can be suitably provided that the supply of fibers into the spinning rotor is interrupted after the occurrence of a thread breakage, and it is re-started only when the thread tension sensor senses the presence of tension in the thread inserted into the spinning rotor. This occurs when the free end of the thread is carried along by and shares the motion of the rotating spinning rotor which means that the thread is now attached to the fibers located in the fiber collection groove and thus is twisted onto them. The centrifugal forces occurring in this process increase the tensile force in the thread and the thread tension sensor 7 senses this increase of the thread tension and closes an electrical contact or a switch by which the electromagnet 14 is excited via line 8 so that the electromagnet 14 pulls back the latch 13, lowering the winding spindle 10 and its thread package onto the distribution roller 9. From this point on, the distribution roller 9 drives the windup spindle 10 in the proper direction for winding up the thread G. This increases the thread tension as between the spinning box 1 and the windup spindle 10 in such a way that the thread G is pulled away from the end face 4' of the draw roller 4 and moves between the two draw rollers 3, 4 where it is pinched. This insertion of the thread into the pinch line of the draw roller pair 3,4 is facilitated by the frustoconical shape of the end surface 4'. The base of the frustoconical surface is preferably immediately adjacent to the cylindrical surface of the draw roller 4. As soon as the thread has reached the pinch line of the draw roller pair 3, 4, its speed of advance is determined exclusively by the speed of this draw roller pair 3, 4. Due to the steady supply of fibers into the fiber collection groove of the spinning rotor, new fibers are constantly deposited on the thread located in the spinning rotor and, thus, thread is continuously being spun and is continuously being wound up on the windup spindle 10.
If another thread breakage occurs or if the windup spindle 10 is exchanged for a new, empty windup spindle, the re-spinning or reattachment process described above is repeated. It should be mentioned that, prior to each re-spinning process, the windup spindle 10 is lifted off from the distribution roller 9 and the latch 13 is brought into the right-most position as shown in FIG. 1 in which it holds the windup spindle 10 up so that the thread package does not come in contact with the distribution roller 9. The lifting of the windup spindle 10 from the distribution roller 9 and the movement of the latch 13 into the position shown in FIG. 1 can be effected manually. The movement of the latch 13 into the position shown in FIG. 1 can also occur automatically or means can be provided for a completely automatic lifting of the windup spool 10. For example, instead of the linearly-moved latch 13, there could be provided a pivotable spring-loaded lever so that, when the current in line 8 is interrupted, associated spring means always guide the windup spindle 10 into a position in which it does not rest on the distribution roller 9. The interruption of current in line 8 can take place automatically, for example, by means of the thread tension sensor, whenever a thread breakage occurs so that, in this case, and after each thread breakage, the windup spindle 10 is automatically moved into its lifted-off position.
The angle α , shown in FIG. 1, of the thread placed against the end face 4' of the draw roller 4 for the purpose of reattachment can suitably be 10° to 45°, and preferably 25° to 35°. Of course, its magnitude depends on the particular position which the thread G occupies on the windup spindle 10. In normal operation, i.e., during the normal thread drawoff by means of the draw roller pair 3, 4, the thread always remains on the pinch line between the draw roller pair 3, 4. The above explanations for reattaching and re-spinning the thread are also valid for the embodiment of the draw roller pair according to FIG. 3.
Inasmuch as the thread guided back into the spinning rotor is drawn off under the control of the thread tension sensor 7 and by means of the windup spindle 10 as soon as it has been twisted onto the fibers located in the fiber collection groove, a thread breakage due to an increased imparting of thread rotations is avoided. Pulling the thread out of the spinning rotor before it has been twisted onto the fibers located in the fiber collection groove of the spinning rotor is also prevented.
In the exemplary embodiment according to FIG. 1, the end face 4' of the draw roller 4 is embodied as a frustoconical element. However, the invention is not limited to such a form for this end surface 4'. For example, in many cases instead of the conical end-face region, an end surface or an end-surface region at right angles with respect to the rotational axis of the draw roller may be provided adjacent to the cylindrical surface of the roller 4. Even in this case, the thread can be pulled into the pinch line of the draw roller pair. Still different embodiments of the particular end surface are possible. Furthermore, it is also possible that the driven draw roller is so disposed and embodied that the thread may be laid against one of its own end surfaces during the re-spinning.
In the context of this invention, the term "end surface" of a draw roller to which the thread may attach, refers to any surface which is transverse to and/or inclined with respect to the rotational axis of the drawoff roller or which annularly envelops or contains the rotational axis, and which is suitable for holding the thread away from the pinch line of the draw roller pair until the thread moves over the pinch line of the draw roller pair due to the tensioning of the thread as a consequence of the start-up of the windup spindle 10. If necessary, therefore, it may be the sidewall of a groove or it may be a radial or at least substantially radial flange of the drawoff roller. The term "end surface" of the draw roller is therefore to be taken in its most encompassing sense and in no case is it limited to a surface at the end of the drawoff roller. Thus, for example, the driven drawoff roller is generally and suitably constituted by only a portion of a shaft extending along the spinning boxes, which is provided with a single section forming a drawoff roller in the vicinity of each spinning box.
As may be seen particularly well from FIG. 2, in this exemplary embodiment, the pinch line of the drawoff roller pair 3,4 is far enough removed from the plane T defined by the thread guide 6 and the thread guide surface of the distribution roller 9 that the thread G which has not yet been pulled into the pinch line of the drawoff roller pair does not lie up against the driven drawoff roller 3 but only against the end surface 4' of the drawoff roller 4. Furthermore, this preferred exemplary embodiment provides that the driven drawoff roller 3 is disposed at some distance from this plane T. In the exemplary embodiment of FIG. 3, which is also a preferred exemplary embodiment, it is provided that the pinch line of the drawoff rollers 3, 4 is located at such a distance from a plane defined by the thread guide 6, (not shown here) and by the thread guiding surface of the distribution roller 9, (also not shown here) that the thread introduced into the spinning rotor for the purpose of re-spinning but which has not yet been pulled over the pinch line of the drawoff roller pair lies up against the outside surface of one drawoff roller 3 and up against the end surface of the other drawoff roller 4. In this exemplary embodiment, the drawoff roller to whose surface the thread attaches is the driven drawoff roller 3.
Preferably, all spinning rotors and drawoff roller pairs of the open-end spinning machine can be continuously power driven, even during the re-spinning, because the re-spinning process may be carried out without stopping the drawoff roller pairs and the spinning rotors. In addition, it is not necessary to reverse the rotational direction of the drawoff rollers for the purpose of re-spinning, rather they may continue to rotate in the same direction of rotation. However, the invention is not limited to this feature, because, in some cases, it may be provided that the drawoff rollers are stopped or reversed in direction during the return passage of the thread so that they themselves guide the thread back to the spinning box whereby means may be provided, for example, a controllable lever, which guides the thread out of the pinch line of the drawoff roller pair before it enters the spinning rotor and which lays it up against an end surface of one of the two drawoff rollers. However, since the invention makes it possible for the drawoff rollers to rotate continuously in the same direction of rotation even during the re-spinning, this technically and operationally particularly simple method is to be regarded as preferred.
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A process and apparatus for repairing thread breakage occurring in an open-end spinning machine which includes a spinning rotor, a pair of draw rollers, a thread tension sensor and thread windup spindles. The end of the thread to be reattached to fibers located within the spinning rotor is guided back from the windup spindle in such a way as to bypass the drawoff rollers and avoid being pinched thereby. The thread is passed alongside one of the draw rollers, preferably on a specially configured conical surface which facilitates eventual reinsertion between the two draw rollers.
The drive of the windup spindle is restarted by the tension sensor when it detects the reattachment of the end of the thread to the fibers in the spinning rotor as manifested by the increased tension in the thread. The increased tension pulls the thread between the drawoff rollers which transport it to the windup spindle at normal operating speed.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a sheet supplying apparatus for supplying a sheet such as a recording sheet or an original sheet to an image forming apparatus such as a copying machine, a printer, a facsimile and the like.
2. Related Background Art
In the past, for example, in an image forming apparatus such as a facsimile system and the like, sheets such as original sheets supplied from a sheet stacking tray are separated one by one by a separation means, and a separated sheet is sent, by a convey means, to a reading portion where image information on the sheet is read, and thereafter the sheet is discharged out of the apparatus.
The sheets stacked on the sheet stacking tray are sent to the separation means from the lowermost one by rotating an auxiliary convey means (referred to as "auxiliary convey roller" hereinafter) disposed below the sheet stacking tray while abutting it against the lowermost sheet of the sheet stack. Since a rotary shaft of the auxiliary convey roller is not shifted and a peripheral surface of the auxiliary convey roller has an ellipic shape or a triangular shape in order to transmit and interrupt the sheet feeding force to the sheet, when the auxiliary convey roller is rotated, the peripheral surface of the auxiliary convey roller is protruded upwardly and retracted downwardly with respect to the sheet stacking tray repeatedly.
On the other hand, there is a conveying mechanism in which a shaft of an auxiliary convey roller can be shifted in an up-and-down direction so that, when it is shifted upwardly, the auxiliary convey roller is abutted against the sheet stack, thereby feeding the sheet. In this mechanism, the upward and downward movement of the auxiliary convey roller is controlled by an electric signal via a plunger or an electromagnetic clutch for shifting the auxiliary convey roller.
However, in case of the auxiliary convey roller having the elliptic or triangular peripheral surface, since the auxiliary convey roller is extended and retracted with respect to the sheet stacking tray, the feeding force is transmitted and interrupted repeatedly with respect to the sheet (i.e. transmitted intermittently). Thus, it takes a long feeding time and the influence upon the-separation means is not stabilized, thereby causing the double-feed of the sheets or the poor sheet feeding.
On the other hand, in the mechanism for controlling the upward and downward movement of the auxiliary convey roller by using the plunger or the electromagnetic clutch, since the number of parts is increased, the apparatus is made expensive and large-sized.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a sheet supplying apparatus wherein the influence of an auxiliary convey roller upon a separation means can be stabilized without using any electric elements and control means therefor.
According to one aspect of the present invention, there is provided a sheet supplying apparatus comprising an auxiliary convey means for conveying sheets stacked on a stacking tray, a separation means for separating and conveying the sheets fed by the auxiliary convey means one by one, a sheet convey means for conveying the sheet separated by the separation means at a conveying speed faster than a conveying speed of the separation means, a supporting means for supporting the auxiliary convey means for shifting movement between a convey position and a non-convey position and for shifting the auxiliary convey means to the convey position when a rotation is transmitted to the separation means, and a retard means driven by the movement of the sheet conveyed by the sheet convey means, thereby retarding the auxiliary convey means to the non-convey position.
According to another aspect of the present invention, there is provided a sheet supplying apparatus comprising an auxiliary convey means for conveying sheets stacked on a stacking tray, a separation means for separating and conveying the sheets fed by the auxiliary convey means one by one, a drive means for driving the separation means and the auxiliary convey means, a sheet convey means for conveying the sheet separated by the separation means at a conveying speed faster than a conveying speed of the separation means, a rotation control means for transmitting one direction rotation (rotation in one direction) of the drive means to a shaft of the drive means to cause the separation and conveyance of the sheet and for interrupting the transmission of the one direction rotation to the drive means when the separated sheet is conveyed by the sheet convey means so that the separation means is driven by the movement of the sheet due to the difference in the conveying speed, thereby causing such interruption by the driven movement of the separation means, a supporting means for supporting the auxiliary convey means for shifting movement between a convey position and a non-convey position and for shifting the auxiliary convey means to the convey position when the one direction rotation is transmitted to the shaft of the drive means, and a retard means for retarding the auxiliary convey means to the non-convey position when the one direction rotation to the drive shaft is interrupted.
With the arrangement as mentioned above, when the one direction rotation from the drive means is transmitted to the drive shaft by the rotation control means, the supporting means shifts the auxiliary convey means to the convey position by such rotation, whereby the sheets stacked on the stacking tray are fed out by the auxiliary convey means toward the separation means. The sheet separated by the separation means is further conveyed by the sheet convey means. In this case, since the conveying speed of the sheet convey means is faster than that of the separation means, the separation means is driven by the movement of the sheet. By this driven movement of the separation means, the rotation control means interrupts the transmission of the one direction rotation to the drive shaft, thereby retarding the auxiliary convey means to the non-convey position by the retard means. In this way, the auxiliary convey means is automatically shifted between the convey position and the non-convey position only by the rotation of the drive means, thereby supplying the sheets successively.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal sectional view of a sheet supplying apparatus according to a first embodiment of the present invention;
FIG. 2 is a plan view of the sheet supplying apparatus of FIG. 1;
FIG. 3 is a perspective view of the sheet supplying apparatus of FIG. 1;
FIG. 4 is a block diagram of a control portion of the sheet supplying apparatus of FIG. 1;
FIG. 5 is a view showing an operation of the sheet supplying apparatus of FIG. 1;
FIG. 6 is a flow chart showing the operation of the sheet supplying apparatus of FIG. 1;
FIG. 7 is a longitudinal sectional view showing a first alteration of the first embodiment;
FIG. 8 is a plan view of the sheet supplying apparatus of FIG. 7;
FIG. 9 is a longitudinal sectional view showing a second alteration of the first embodiment;
FIG. 10 is a plan view of the sheet supplying apparatus of FIG. 9;
FIG. 11 is an enlarged view showing a main portion of a third alteration of the first embodiment;
FIG. 12 is an enlarged view showing a main portion of a fourth alteration of the first embodiment;
FIG. 13 is a plan view showing a fifth alteration of the first embodiment;
FIG. 14 is a plan view showing a sixth alteration of the first embodiment;
FIGS. 15 and 16 are views showing a rotating condition of a friction belt shown in FIG. 14;
FIG. 17 is a plan view showing a seventh alteration of the first embodiment;
FIGS. 18 and 19 are views showing an operating condition of a sector member shown in FIG. 17;
FIG. 20 is a plan view showing an eighth alteration of the first embodiment;
FIG. 21 is a plan view showing a ninth alteration of the first embodiment;
FIG. 22 is a plan view of a sheet supplying apparatus according to a second embodiment of the present invention;
FIG. 23 is a perspective view of the sheet supplying apparatus of FIG. 22;
FIGS. 24 and 25 are enlarged views of a main portion of the sheet supplying apparatus of FIG. 22, showing an operation thereof;
FIG. 26 is a longitudinal sectional view showing a first alteration of the second embodiment;
FIG. 27 is a plan view of the sheet supplying apparatus of FIG. 26;
FIGS. 28 and 29 are enlarged views of a main portion of the sheet supplying apparatus of FIG. 26, showing an operation thereof;
FIG. 30 is a longitudinal sectional view showing a second alteration of the second embodiment;
FIG. 31 is a plan view of the sheet supplying apparatus of FIG. 30;
FIG. 32 is a longitudinal sectional view of a sheet supplying apparatus according to a third embodiment of the present invention;
FIG. 33 is a plan view of the sheet supplying apparatus of FIG. 32;
FIG. 34 is a perspective view of the sheet supplying apparatus of FIG. 32;
FIG. 35 is a longitudinal sectional view showing an operation of the sheet supplying apparatus of FIG. 32;
FIG. 36 is a longitudinal sectional view showing a first alteration of the third embodiment;
FIG. 37 is a plan view of the sheet supplying apparatus of FIG. 36;
FIG. 38 is a longitudinal sectional view of a sheet supplying apparatus according to a fourth embodiment of the present invention;
FIG. 39 is a plan view of the sheet supplying apparatus of FIG. 38;
FIG. 40 is a flow chart showing a control of the sheet supplying apparatus of FIG. 38;
FIG. 41 is a plan view showing a first alteration of the third embodiment;
FIG. 42 is a block diagram of a control portion of the sheet supplying apparatus of FIG. 41;
FIG. 43 is a flow chart showing a control of the sheet supplying apparatus of FIG. 41;
FIG. 44 is a side view showing another example of a main portion of a means for applying a load to auxiliary convey pulleys in previous embodiments;
FIGS. 45 and 46 are plan views showing another example of a main portion of a means for applying a load to auxiliary convey pulleys in previous embodiments;
FIG. 47 is a longitudinal sectional view of a sheet supplying apparatus according to a fifth embodiment of the present invention;
FIG. 48 is a plan view of the sheet supplying apparatus of FIG. 47;
FIG. 49 is a flow chart showing a control of the sheet supplying apparatus of FIG. 47;
FIG. 50 is a flow chart according to a first alteration of the fifth embodiment;
FIG. 51 is a flow chart according to a second alteration of the fifth embodiment;
FIG. 52 is a flow chart according to a sixth embodiment of the pre sent invention;
FIG. 53 is a flow-chart according to a first alteration of the sixth embodiment; and
FIG. 54 is a flow chart according to a second alteration of the sixth embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be explained with reference to the accompanying drawings.
First of all, a first embodiment of the present invention will be described referring to FIGS. 1 to 3.
In this embodiment, a sheet supplying apparatus according to the present invention is applied to a facsimile system as an image forming apparatus. A frame 2 of the sheet supplying apparatus 1 comprises an upper frame 2b and a lower frame 2a which define a sheet convey path 2c therebetween. At an upstream side of the sheet supplying apparatus 1, there is arranged a sheet stacking tray 13 on which a plurality of sheets S to be read are stacked, and a sheet detection sensor 15 for detecting the presence/absence of the sheet S is disposed on the sheet stacking tray 13.
At a downstream side of the sheet detection sensor 15, there are arranged an auxiliary convey roller (auxiliary convey means) 3 for feeding out and conveying the sheet S, and a separation roller (separation means) 5 for separating the sheet S one by one when plural sheets are fed out. These elements will be fully described later. At a downstream side of the separation roller 5, there are arranged in order a pair of convey rollers 16 for conveying the separated sheet S, a reading portion 17 for reading image information on the sheet S, and a pair of discharge rollers 19 for discharging the read sheet out of the apparatus. An aligning sensor 20 for detecting a leading end of the separated and conveyed sheet S is disposed between the paired convey rollers 16 and the reading portion 17. Incidentally, a conveying speed V 2 of the convey roller pair 16 for conveying the sheet S is selected to be faster than a conveying speed V 1 of the separation roller 5.
As shown in FIG. 2, within the lower frame 2a below the sheet stacking tray 13, a frame 21 having side plates 21a, 21b is arranged, and a separation shaft (drive shaft) 6 rotatably supported by the side plates 21a, 21b has a large diameter portions 6a, 6b secured thereto as shown in FIG. 3. At the left and right of the large diameter portion 6aof the separation shaft 6, the separation roller 5 having a boss 5a and a separation gear 35 having a boss 35a are rotatably mounted on the shaft, respectively. The large diameter portion 6a, the bosses 5a , 35a having the same diameter as that of the large diameter portion, and a clutch spring 11a wound around these elements constitute a first clutch (rotation control means) 11 comprising a one-way rotation clutch.
A motor gear 33 meshed with the separation gear 35 is secured to an output shaft 32 of the drive motor (drive means) 31 fixed to a fixed member (not shown ) and is rotated in a direct ion shown 37 by the arrow in FIG. 2. Incidentally, the first clutch 11 is engaged when the separation gear 35 is rotated in a direction shown by the arrow A (FIG. 3) by the motor gear 33, thereby transmitting a rotational force of the drive motor 31 to the separation roller 5 and the separation shaft 6. Upon the engagement of the first clutch 11, the separation roller 5 and the separation shaft 6 are rotated in a sheet supplying direction shown by the arrow A (referred to as "normal rotation direction" hereinafter).
As shown in FIGS. 2 and 3, in the proximity of the large diameter portion 6b of the separation shaft 6, a reverse rotation driven pulley 51a having a barrel 51b having the same diameter as that of the large diameter portion is rotatably mounted on the shaft. The reverse rotation driven pulley 51a is connected to a reverse rotation drive pulley 49 secured to the output shaft 32 of the drive motor 31 via a reverse rotation belt 50 so that, when the drive motor 31 is rotated, the reverse rotation driven pulley is always rotated in a direction shown by the arrow B in FIG. 3 (referred to as "reverse rotation direction" hereinafter).
The barrel 51b of the reverse rotation driven pulley 51a, the large diameter portion 6b of the separation shaft 6 and a clutch spring 12a wound around these elements constitute a second clutch (reverse rotation clutch) 12 comprising a one-way rotation clutch. Incidentally, a winding direction of the clutch spring 12a of the second clutch 12 is the same as that of the clutch spring 11a of the first clutch 11, and a loosing torque of the clutch spring 12a with respect to the separation shaft 6 is greater than that of the clutch spring 11a.
Incidentally, as the means for transmitting the reverse rotation power, a pair of gears may be used in place of the above-mentioned reverse rotation belt 50, or a torque limiter which is disconnected from the drive motor 31 when a predetermined load is applied may be used in place of the above-mentioned second clutch 12.
A support shaft 22 is supported by the frame 21 at an upstream side of the separation shaft 6, and an intermediate portion of a support member 7 having side wall plates 7a, 7b is rotatably mounted on the support shaft 22. The auxiliary convey roller 3 having an auxiliary convey pulley 23 secured thereto is rotatably mounted on the support member 7 via a pivot shaft 25. Further, an idle pulley 27 is rotatably mounted on the support member 7 via a pivot shaft 26. A cushion member (friction member) 29 for applying the load to the idle pulley 27 to generate a rotational force (described layer) for rotating the support member 7 is arranged between the idle pulley 27 and the side wall plate 7a.
A drive pulley 30 is secured to the left end (lower end in FIG. 2) of the separation shaft 6 and is connected to the auxiliary convey pulley 23 and the idle pulley 27 via a shift belt 9. When the drive pulley 30 integral with the separation shaft 6 is rotated in the normal rotation direction A to rotate the shift belt in the normal rotation direction shown by the arrow C (anti-clockwise direction in FIG. 1), the support member 7 is rotated around the support shaft 22 in a direction shown by the arrow E (normal rotation direction) by the power due to the loading action of the cushion member 29. On the other hand, when the drive pulley 30 is rotated in the reverse rotation direction B to rotate the shift belt 9 in a direction shown by the arrow D, the support member 7 is rotated in a direction shown by the arrow F in FIG. 1 (reverse rotation direction).
The rotation of the support member 7 in the normal rotation direction is regulated by a normal rotation stopper 42 (FIG. 1) disposed below the support member 7, and the rotation of the support member 7 in the reverse rotation direction is regulated by a reverse rotation stopper 41. When the support member 7 is rotated in the normal rotation direction as mentioned above, the auxiliary convey roller 3 is shifted upwardly, so that an upper portion of the peripheral surface of this roller is protruded upwardly through an opening (not shown) formed in the sheet stacking tray 13 to abut against a lower surface of the sheet stack S.
An original hold-down member 43 is arranged above the auxiliary convey roller 3, which hold-down member has a base portion pivotally mounted on the upper frame 2b and a free end portion biased downwardly by a compression spring 45. When the auxiliary convey roller 3 is shifted upwardly, the original hold-down member 43 is abutted against the auxiliary convey roller 3 so that the latter provides a conveying force for conveying the sheet S. Further, a separation member 46 having a base portion pivotally mounted on the upper frame 2b is disposed above the separation roller 5. The separation member 46 is abutted against the separation roller 5 by a compression spring 47 to cooperate with the separation roller 5 for separating the sheets S.
Incidentally, the pair of convey rollers 16 and the pair of discharge rollers 19 are connected to the drive motor 31 via a transmission system such as a gear train or a belt (not shown). Accordingly, when the drive motor 31 is rotated, the separation roller 5, the auxiliary convey roller 3, the pair of convey rollers 16 and the pair of discharge rollers 19 are driven simultaneously.
FIG. 4 is a block diagram showing an example of a control portion of the sheet supplying apparatus of the present invention. In FIG. 4, the reference numeral 55 denotes a control portion of a facsimile system and the like having the sheet supplying apparatus according to the present invention. The sheet detection sensor 15, reading portion 17, aligning sensor 20 and drive motor 31 are controlled by the control portion 55.
Next, an operation of the sheet supplying apparatus according to the present invention will be explained.
First of all, an operation of the auxiliary convey system for feeding out the sheets S on the sheet stacking tray 13 will be described.
As shown in FIG. 1, in a condition that the auxiliary convey roller 3 is retarded below the sheet stacking tray 13, the separation roller 5 and the drive pulley 30 integral with the separation shaft 6 are rotated in the normal rotation direction (shown by the arrow A) in a manner which will be described later. As a result, when the rotation of the drive pulley 30 is transmitted to the idle pulley 27 and the auxiliary convey pulley 23 via the shift belt 9, the support member is firstly rotated around the pivot shaft 22 in the normal rotation direction E until it is stopped by the normal rotation stopper 42. Then, the auxiliary convey roller 3 and the idle pulley 27 are rotated in directions shown by the arrow G in FIG. 1, respectively.
In order to operate the support member 7 and the auxiliary convey roller 3 as mentioned above, it is necessary to reduce a rotational resistance of the support member 7 as small as possible, because, in a condition that the shift belt 9 is stopped, the auxiliary convey pulley 23 or the idle pulley 27 must be subjected to the rotational resistance to an extent that the support member 7 can be kept stationary at any position within a rotational range of the support member 7 without being rotated by the weight of the auxiliary convey roller 3, auxiliary convey pulley 23, pivot shaft 25, idle pulley 27, pivot shaft 26 and support member 7 themselves. To this end, in the illustrated embodiment, as shown in FIG. 2, the cushion member 29 is mounted on the pivot shaft 26 between the idle pulley 27 and the side wall plate 7a to apply the load to the idle pulley 27, thereby permitting the support member 7 to be made stationary at any position. Incidentally, the normal rotation stopper 42 is positioned so that the auxiliary convey roller 3 is subjected to an appropriate urging force from the original hold-down member 43 when it is positioned above the sheet stacking tray 13.
On the other hand, when the drive pulley 30 is rotated in the reverse rotation direction shown by the arrow B in FIG. 1 to transmit the driving force to the idle pulley 27 and the auxiliary convey pulley 23 via the shift belt 9, as shown in FIG. 1, the support member 7 is firstly rotated around the support shaft 22 in the reverse rotation direction (shown by the arrow F) until it is stopped by the reverse rotation stopper 41. The reverse rotation stopper 41 is positioned so that the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 at this point. Further, within the rotational range of the support member 7, it is designed so that an outer peripheral length defined by the auxiliary convey pulley 23, idle pulley 27 and drive pulley 30 is substantially constant, whereby the shift belt 9 is prevented from being tensioned too great or too small during the rotation of the shift belt 9.
Next, a reading operation of the facsimile system 100 incorporating the sheet supplying apparatus 1 therein will be explained with reference to a flow chart shown in FIG. 6.
First of all, when an operator sets the sheets S on the sheet stacking tray 13 (step S1), the sheet detection sensor 15 detects the presence of the sheets (step S2), and a detection signal from the sensor is sent to the control portion 55. The drive motor 31 is rotated in the direction shown by the arrow 37 (step S3) by a signal from the control portion 55, thereby rotating the separation gear 35 in the direction A (normal rotation direction). Since the normal rotation of the separation gear 35 tightens the clutch spring 11a, the first clutch 11 is engaged or applied. The engagement of the first clutch 11 causes the separation gear 35 to connect to the large diameter portion 6aof the separation shaft 6 and the boss 5a of the separation roller 5, with the result that the separation roller 5 and the separation shaft 6 are rotated in the direction A.
On the other hand, by the rotation of the drive motor 31, the reverse rotation driven pulley 51a and the barrel 51b formed integrally therewith are rotated in the direction B (reverse rotation direction) in FIG. 3. The large diameter portion 6b of the separation shaft 6 constituting the second clutch 12 is rotated in the direction A, and the barrel 51b is rotated in the opposite direction B. However, since the clutch spring 12a acts in the loosing direction, the rotation of the separation shaft 6 in the direction A is not obstructed. That is, by the rotation of the drive motor 31, since the first clutch 11 is engaged and the second clutch 12 is disengaged, the rotation of the drive motor 31 is transmitted to the separation shaft 6 only through the first clutch 11, and the second clutch 12 does not concern to the transmitting operation in this case.
When the separation shaft 6 and the drive pulley 30 integral therewith are rotated in the direction A, as mentioned above, the support member 7 is rotated in the normal rotation direction and the auxiliary convey roller 3 is abutted against the sheet stack S, thereby supplying the sheets on the sheet stacking tray 13. The supplied sheets are sent to the separation roller 5, and then the lowermost sheet S is sent to a nip of the separation roller 5. If plural sheets S are sent to the nip, these sheets are separated, and only one sheet S is sent to the pair of convey rollers 16.
By the way, when the operator sets the sheets S on the sheet stacking tray 13, if the sheets S are inserted at a speed slower than a peripheral speed of the auxiliary convey roller 3, the sheets S are pulled by the auxiliary convey roller 3; whereas, if the sheets S are inserted at a speed faster than the peripheral speed of the auxiliary convey roller 3, the auxiliary convey roller 3 is driven by the movement of the sheets S, so that the auxiliary convey roller is rotated faster than a speed given by the drive motor 31.
By the above rotation of the auxiliary convey roller 3, since a length of the shift belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 tends to be increased and a length of the shift belt 9 between the idle pulley 27 and the drive pulley 30 tends to be decreased, the support member 7 is rotated in the direction F in FIG. 1. As a result, since the auxiliary convey roller 3 is lowered to be spaced apart from the sheet S, it is not feared that the sheets S are caught by the auxiliary convey roller 3 during the sheet inserting operation, thereby damaging the sheet S.
Thereafter, when the operator stops the insertion of the sheets S, the auxiliary convey roller 3 is abutted against the sheet S again, thereby starting the supply of the sheet S. Incidentally, the rotation of the support member 7 is regulated by the reverse rotation stopper 41 so that the support member 7 is not excessively rotated in the reverse rotation direction (step S3). The sheets S supplied by the auxiliary convey roller 3 are separated one by one from the lowermost one by the separation roller 5 and the separation member 46. When the leading end of the separated sheet is detected by the aligning sensor 20, the control portion 55 controls to stop the drive motor 31 (step S4).
In this condition, the image density and resolving power during the reading of image information are set by the operator, and the reading is started (step S5). The drive motor 31 is rotated by the signal from the control portion 55 (step S6) to rotate the separation roller 5 and the separation shaft 6 in the normal rotation direction A.
The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step S7), and the image information is read (step S8), and then the sheet is discharged out of the apparatus by the pair of discharge rollers 19 (step S9). Thereafter, when the fact that the sheet(s) still exist on the sheet stacking tray 13 by the sheet detection sensor 15 (step S10), a next sheet is conveyed in the same manner as mentioned above. When the presence of the sheet S is not detected by the sensor 15, it is considered that the reading of all of the sheets S has been completed, and the control portion 55 controls to stop the drive motor 31 (step S11).
In the above step S7, when the sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16, since the peripheral speeds V 2 of the paired convey rollers 16 are faster than the peripheral speed V 1 of the separation roller 5, the separation roller 5 is driven by the movement of the conveyed sheet S. Accordingly, the separation roller 5 is rotated in the normal rotation direction at a speed faster than the rotational speed given by the drive motor 31, i.e., the rotational speed of the separation gear 35.
In FIGS. 2 and 3, since the boss 5a of the separation roller 5 is rotated at a speed faster than that of the large diameter portion 35a of the separation gear 35, the clutch spring 11a wound around these elements acts in the loosing direction, thereby interrupting the power transmitting operation of the first clutch 11. As a result, the separation gear 35 is rotated idly, and the power transmission to the separation shaft 6 is interrupted.
On the other hand, although the loosing torque due to the clutch spring 12a acts on the large diameter portion 6b constituting the second clutch 12, as mentioned above, since the loosing torque of the second clutch 12 to the separation shaft 6 is greater than that of the first clutch 11, the separation shaft 6 is rotated in the reverse rotation direction B. That is, when the first clutch 11 is disengaged or released, the separation shaft 6 is rotated in the reverse rotation direction (shown by the arrow B) by the loosing torque of the second clutch 12. Incidentally, even when the separation shaft 6 is rotated in the reverse rotation direction as mentioned above, the separation roller 5 is still driven by the movement of the sheet S in the normal rotation direction.
When the separation shaft 6 and the drive pulley 30 integral therewith are rotated in the reverse rotation direction, the shift belt 9 is rotated in the reverse direction shown by the arrow D, thereby rotating the support member 7 in the reverse rotation (shown by the arrow F) around the support shaft 22. The rotation of the support member 7 continues until the downstream end of the support member 7 is engaged by the reverse rotation stopper 41. By the reverse rotation of the support member 7, the auxiliary convey roller 3 is shifted to be spaced apart from the sheet stack S on the sheet stacking tray 13, thereby interrupting the transmission of the conveying force to the sheet S.
Thereafter, when the trailing end of the sheet S leaves the separation roller 5, the driving of the separation roller 5 by the movement of the sheet S is stopped. Consequently, the first clutch 11 is engaged, with the result that the shift belt 9 is rotated in the normal rotation direction and the support member 7 is also rotated in the normal rotation direction (shown by the arrow E) to abut the auxiliary convey roller 3 against the next sheet S, thereby supplying the next sheet S. When the first clutch 11 is engaged again to rotate the separation shaft 6 in the normal direction as mentioned above, the power transmitting action of the second clutch 12 for transmitting the reverse rotation force is released.
Incidentally, in some cases, there is no need to provide the auxiliary conveying force to the next sheet S, i.e., there is a case where a plurality of sheets S are properly wedged in the nip between the separation roller 5 and the separation member 46 thereby to convey the sheet only by the separation roller 5. In such a case, before the auxiliary convey roller 3 is protruded above the sheet stacking tray 13 to restore the auxiliary conveying force, the first clutch 11 is disengaged again. To this end, a time period during which the sheet S is conveyed from the separation position to the convey roller pair 16 by the separation roller 5 is so selected to be shorter than a time period during which the support member 7 is shifted between the normal rotation stopper 42 and the reverse rotation stopper 41, i.e., a time period during which the auxiliary convey roller 3 is shifted from a position where it is furthest spaced apart from the sheet stack S on the sheet stacking tray 13 to a position where it is abutted against the sheet stack S, thereby preventing the unnecessary conveying force from acting on the next sheet S at a proper timing (step S7).
With the above-mentioned arrangement of the sheet supplying apparatus according to the present invention, it is possible to automatically transmit or interrupt the auxiliary conveying force with respect to the sheet S without any complicated control only by the single drive motor 31, and to improve the setting ability of the sheets S on the sheet stacking tray 13.
FIGS. 7 and 8 show a first alteration of the first embodiment. In this first alteration, as the means for driving the auxiliary convey roller 3, gears are used in place of the above-mentioned shift belt 9.
In FIGS. 7 and 8, an auxiliary convey gear 56 is coaxially secured to the auxiliary convey roller 3, which gear 56 is connected to a support member gear 59 rotatably mounted on the support shaft 22 via an auxiliary convey transmission gear 57 rotatably mounted on a support shaft 57a of the support member 7. Further, the support member gear 59 is connected to a drive gear 61 secured to the separation shaft 6 via a drive transmission gear 60 rotatably mounted on a support shaft 60a of the frame 21. The cushion member 29 for applying the load to the rotation of the auxiliary convey roller 3 is disposed between the auxiliary convey gear 56 and the side wall plate 7a of the support member 7.
With the above-mentioned driving force transmitting arrangement, by selecting the disposition and the numbers of teeth of various gears, it is possible to set the rotational speed and the rotational range of the support member 7 relatively freely even if there are certain limitations.
FIGS. 9 and 10 show a second alteration of the first embodiment.
In this second alteration, the support member 7 is supported on the separation shaft 6. The drive gear 61 is connected to the auxiliary convey gear 56 integrally formed with the auxiliary convey roller 3 via an idle gear 62 rotatably mounted on the support member 7 via a support shaft 62a. With this arrangement, it is possible to reduce the number of parts, thereby making the apparatus inexpensive. Incidentally, in place of the idle gear 62, a belt may be used to transmit the driving force.
FIG. 11 shows a third alteration of the first embodiment.
In this third alteration, the auxiliary convey roller 3 and the auxiliary convey pulley 23 are interconnected via a clutch. In FIG. 11, a spring clutch 63 is arranged between the auxiliary convey roller 3 and the auxiliary convey pulley 23, which spring clutch 63 serves to interrupt the driving force when the auxiliary convey roller 3 is rotated in the normal rotation direction (shown by the arrow G in FIG. 1).
With the above-mentioned arrangement of the drive transmitting system for the auxiliary convey roller 3, even when the drive pulley 30 is rotated in the reverse rotation direction, since the auxiliary convey roller 3 is driven by the movement of the sheet S, it is possible to prevent the sheet (original) S from being smudged by the rubbing of the auxiliary convey roller 3 and to permit the smooth reverse rotation of the support member 7. Further, when the operator sets the sheet S, even if the sheets s are inserted at a speed faster than the peripheral speed of the auxiliary convey roller 3, since the spring clutch 63 is disengaged so that the auxiliary convey roller 3 is driven by the movement of the sheet S, the sheet S is not damaged.
FIG. 12 shows a fourth alteration of the first embodiment. In this alteration, another loading means for applying the load to the idle pulley 27 of the support member 7 is shown.
In FIG. 12, a friction plate 65 is freely mounted on the pivot shaft 26 at an inner end position of the idle pulley 27, which friction plate 65 is non-rotatably secured to the support member 7. The friction plate 65 is urged against the idle pulley 27 by an elastic force of a compression spring 66 disposed between the side wall plate 7b of the support member 7 and the friction plate 65, thereby applying the load (resistance) to the rotation of the idle pulley 27. Incidentally, as mentioned above, by using this arrangement, the load may be applied to the rotation of the auxiliary convey roller 3.
Next, alterations of the reverse rotation means according to the first embodiment will be explained with reference to FIGS. 13 to 21. In these alterations, a plurality of other means for rotating the separation shaft 6 in the reverse rotation direction are shown.
In FIG. 13, a friction reverse rotation pulley 67 is rotatably mounted on an outer end of the large diameter portion 6b of the separation shaft 6, which pulley 67 is connected to a reverse rotation drive pulley 49 via a reverse rotation belt 50. The friction reverse rotation pulley 67 has a friction member having high friction of coefficient provided on an interface between the large diameter portion 6b and the friction reverse rotation pulley. A compression spring 69 is disposed between the friction reverse rotation pulley 67 and a wall plate 21b of the frame 21, thereby urging the friction member of the friction reverse rotation pulley 67 against the large diameter portion 6b with an appropriate force. Although the friction reverse rotation pulley 67 is rotated in the reverse rotation direction through the reverse rotation belt 50, when the first clutch 11 is engaged and the separation shaft 6 is rotated in the normal rotation direction, the friction reverse rotation pulley 67 is slipped with respect to the large diameter portion 6b. When the first clutch 11 is disengaged, the rotation of the friction reverse rotation pulley 67 is transmitted to the separation shaft 6 by the friction force between the large diameter portion 6b and the friction reverse rotation pulley 67, thereby rotating the separation shaft 6 in the reverse rotation direction.
FIG. 14 shows a further alteration of the reverse rotation means for the separation shaft 6.
In FIG. 14, a friction belt 70 is wound around and extends between a reverse rotation driven pulley 6c integrally formed with the separation shaft 6 and a reverse rotation drive pulley 49. When the first clutch is engaged to transmit the driving force, as shown in FIG. 15, since the rotational direction of the output shaft 32 of the drive motor 31 and accordingly the reverse rotation drive pulley 49 is opposite to the rotational direction of the separation shaft 6 and accordingly the reverse rotation driven pulley 6c, the friction belt 70 is slipped not to rotate the separation shaft 6. When the first clutch 11 is disengaged, as shown in FIG. 16, the separation shaft 6 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 3) by the friction force between the reverse rotation drive pulley 49 and the reverse rotation driven pulley 6c, and the friction belt 70.
FIGS. 17 to 19 show an example that a sector member is used as the reverse rotation means for the separation shaft 6.
In FIGS. 17 to 19, a sector member 71 is secured to a base portion of the support shaft 22, and a high friction member provided on a peripheral surface of the sector member is abutted against the large diameter portion 6b of the separation shaft 6. The sector member 71 is biased toward an anti-clockwise direction in FIG. 18 by an elastic force of a tension spring 72 having one end secured to the frame 21.
When the driving force is being transmitted by the first clutch 11, as shown in FIG. 18, since the separation shaft 6 is rotated in the normal rotation direction A, the sector member 71 is rotated in an upward direction shown by the arrow S in opposition to the elastic force of the tension spring 72. When the first clutch 11 is disengaged to disconnect the separation gear 35 from the separation shaft 6 thereby to permit the free rotation of the separation shaft 6, as shown in FIG. 19, the sector member 71 is rotated in a direction shown by the arrow T by the tension spring 72, thereby rotating the separation shaft 6 in the reverse rotation direction B.
FIG. 20 shows a still further example of the reverse rotation means for the separation shaft 6.
In FIG. 20, a leaf spring 73 having a base portion secured to the support member 7 is abutted against the auxiliary convey roller 3. The support member 7 is biased in a clockwise direction around the support shaft 22 by an elastic force of a tension spring 75. When the driving force is being transmitted by the first clutch 11, the leaf spring 73 applies to the auxiliary convey roller 3 a load sufficient to rotate the support member 7 in an anti-clockwise direction (shown by the arrow E) in FIG. 20 in opposition to the elastic force of the tension spring 75. When the first clutch 11 is disengaged, the support member 7 is rotated in a clockwise direction (shown by the arrow F) by the tension spring 75, thereby separating the auxiliary convey roller 3 from the sheet stack S on the sheet stacking tray 13.
Incidentally, in place of the leaf spring 73, the load sufficient to rotate the support member 7 in opposition to the elastic force of the tension spring 75 may be applied to the auxiliary convey pulley 23 or the idle pulley 27 by the arrangement shown in FIG. 2 or FIG. 12.
FIG. 21 shows an example that the driving force is transmitted from the separation gear 35 to the reverse rotation driven pulley 51a. In FIG. 21, a reverse rotation drive gear 76 meshed with the separation gear 35 is rotatably mounted on the support shaft 22 and is connected to the reverse rotation driven pulley 51a via reverse rotation belt 50.
Next, a second embodiment of the present invention will be explained with reference to FIGS. 22 and 23.
In FIGS. 22 and 23, according to the second embodiment, a timing plate (timing setting means) 80 is secured to the support shaft 22. Since the other construction is the same as that shown in FIGS. 1 and 2, the explanation thereof will be omitted. The timing plate 80 serves to adjust a timing of the rotation of the support member 7 in a manner which will be described later.
An operation of this embodiment will be explained.
In the operation of the auxiliary conveying system, as shown in FIG. 1, from the condition that the auxiliary convey roller 3 is positioned below the sheet stacking tray 13, when the auxiliary convey roller 3 is rotated in the direction shown by the arrow A in FIG. 1, the driving force is transmitted to the auxiliary convey pulley 23 and the idle pulley 27 by the shift belt 9. As a result, as shown in FIG. 24, in a condition that the timing plate 80 can be rotated, the support member 7 is so designed that it cannot be lifted and rotated by the weight of the auxiliary convey roller 3, auxiliary convey pulley 23, pivot shaft 25, idle pulley 27, pivot shaft 26, timing plate 80 and support member 7 themselves.
However, as shown in FIG. 25, when the timing plate 80 is abutted against the support member 7 to regulate the rotation of the former, the cushion member 29 applies the load to the rotation of the idle pulley 27 by the friction force. As a result, as shown in FIG. 5, the support member 7 is rotated in the anti-clockwise direction (shown by the arrow E) around the support shaft 22 until it is stopped by the normal rotation stopper 42, and then the auxiliary convey pulley 23 and the idle pulley 27 and accordingly the auxiliary convey roller 3 are rotated.
To the contrary, when the drive pulley 30 is rotated in the direction shown by the arrow B in FIG. 1, the driving force is transmitted to the auxiliary convey pulley 23 and the idle pulley 27 via the shift belt 9, thereby firstly rotating the support member 7 in the clockwise direction (shown by the arrow F) around the support shaft 22 until it is abutted against the reverse rotation stopper 41. The reverse rotation stopper 41 is so arranged that the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 at this point, and the timing plate 80 is returned to a condition shown in FIG. 24.
The reading operation in this embodiment is effected in the same manner as that of the first embodiment explained in connection with FIG. 6. Accordingly, in this second embodiment, the step S7 in FIG. 6 will be explained in connection with this embodiment. When the separated sheet S is conveyed by the pair of convey rollers 16 and the separation roller 5 is driven by the movement of the sheet, the clutch spring 11a is disenabled, with the result that the support member 7 is rotated until it is abutted against the reverse rotation stopper 41, thereby interrupting the auxiliary conveying force of the auxiliary convey roller 3 as in the first embodiment.
Further, there is a case where the auxiliary conveying force for the next sheet is not required, i.e., a case where a plurality of sheets S are properly wedged into the nip between the separation roller 5 and the separation member 46 to thereby convey the sheet only by the separation roller 5. In such a case, the first clutch 11 is disengaged before the auxiliary convey roller 3 is protruded above the sheet stacking tray 13 to restore the auxiliary conveying force as in the first embodiment.
To this end, the timing plate 80 so sets that a time period during which the sheet S is conveyed from the separation position to the convey roller pair 16 by the separation roller 5 becomes shorter than a time period during which the support member 7 is shifted between the normal rotation stopper 42 and the reverse rotation stopper 41, i.e., a time period during which the auxiliary-convey roller 3 is shifted from a position where it is furthest spaced apart from the sheet stack S on the sheet stacking tray 13 to a position where it is abutted against the sheet stack S, thereby preventing the unnecessary conveying force from acting on the next sheet S at a proper timing (step S7). Further, since the timing for applying the auxiliary conveying force can be adjusted by changing the configuration of the timing plate 80, it is possible to design the apparatus relatively freely even when there is the spatial limitation, thereby making the apparatus small-sized.
FIGS. 26 to 29 show a first alteration of the second embodiment wherein the auxiliary convey roller 3 is driven by gears in place of the shift belt 9, and, particularly, FIGS. 28 and 29 are perspective view showing the operation of the timing plate 80 when the drive gear 61 is rotated in a direction shown by the arrow A from a condition shown in FIG. 26.
First of all, as shown in FIG. 28, in a condition that the timing plate 80 can be rotated, since the load is not applied to the rotation of the auxiliary convey gear 56, the support member 7 is not lifted. Thereafter, as shown in FIG. 29, when a pin 80a of the timing plate 80 is abutted against the support member 7 to regulate the rotation of the plate, since the load is applied to the auxiliary convey gear 56 by the friction force of the cushion member 29, the support member 7 is rotated in an anti-clockwise direction (shown by the arrow E) in FIG. 26, thereby protruding the auxiliary convey roller 3 above the sheet stacking tray 13. In this way, the sheet S is conveyed by the rotation of the auxiliary convey roller. With this arrangement, by performing the adjustment of the timing plate 80 and by setting the disposition and the numbers of teeth of various gears, it is possible to design the apparatus relatively freely even when there are any severe limitations.
FIGS. 30 and 31 show a second alteration wherein the support member 7 is mounted on the separation shaft 6. The reference numeral 62 denotes an idle gear for transmitting the driving force of the drive gear 661 to the auxiliary convey gear 56; and 62a denotes a support shaft. The operation of the timing plate 80 in this case is the same as the first alteration shown in FIGS. 28 and 29.
With this arrangement, it is possible to reduce the number of parts, thereby making the apparatus inexpensive. Incidentally, even when the driving force is transmitted by a belt in place of the idle gear 62, there arises no problem.
Next, a third embodiment of the present invention will be explained with reference to FIGS. 32 to 37.
In this third embodiment, as shown in FIGS. 32 to 34, a cleaning roller (cleaning means) 90 is rotatably mounted on the pivot shaft 26 for the idle pulley 27. Since the other construction is the same as those in the above first and second embodiment, the explanation thereof will be omitted.
The cleaning roller 90 is provided at its its peripheral surface with a high adhesive member so that, when the roller is abutted against the separation roller 5, paper powder or the like adhered to the separation roller 5 can be removed.
When the drive motor 31 is rotated by the signal from the control portion 55 to rotate the separation gear 35 in a direction shown by the arrow A in FIG. 32, the first clutch 11 is engaged, with the result that the support member 7 is rotated in an anti-clockwise direction (shown by the arrow E) in FIG. 35, thereby abutting the auxiliary convey roller 3 against the sheet S to supply the sheet S. When the sheet S separated by the separation roller 5 is conveyed by the pair of convey rollers 16, the first clutch 11 is disengaged and the support member 7 is rotated in a clockwise direction (shown by the arrow F) from the condition shown in FIG. 35 to return to the condition shown in FIG. 32. Such rotation of the support member 7 causes the auxiliary convey roller 3 to lower below the sheet stacking tray 13 and causes the cleaning roller 90 to abut against the separation roller 5, thereby automatically cleaning the peripheral surface of the separation roller 5.
Thereafter, when the trailing end of the sheet S has passed through the separation roller 5 so that the separation roller 5 is not driven by the movement of the sheet S, the first clutch 11 is engaged to rotate the support member 7 in the anti-clockwise direction (shown by the arrow E), thereby stopping the cleaning operation of the cleaning roller 90 regarding the separation roller 5.
FIGS. 36 and 37 show a first alteration of the third embodiment wherein the auxiliary convey roller 3 is driven by gears in place of the belt. In this alteration, the cleaning roller 90 is mounted at a downstream side of the support member 7, and the other construction is the same as that in the second embodiment shown in FIGS. 7 and 8. Also in this alteration, when the sheet S is supplied by the auxiliary convey roller 3, the cleaning roller 90 is spaced apart from the separation roller 5. When the separation roller 5 is driven by the movement of the separated sheet S and the first clutch 11 is disengaged, the cleaning roller 90 is abutted against the separation roller 5, thereby cleaning the peripheral surface of the separation roller.
As mentioned above, when the separation means is driven by the movement of the separated sheet, the support member for supporting the auxiliary convey means is rotated to separate the auxiliary convey means from the sheet, thereby interrupting the transmission of the conveying force to the sheet. As a result, it is possible to stabilize the separation means without any complicated control and with low cost and without the influence of the auxiliary conveying force upon the separation means, and to improve the setting ability of the sheets. Further, since the timing that the support member for supporting the auxiliary convey means can be adjusted, it is possible to design the apparatus relatively freely and to make the apparatus small-sized.
Next, a fourth embodiment of the present invention will be explained with reference to FIGS. 38 to 40.
In this embodiment, the construction of the clutch and the control of the control portion are different from these in the first embodiment. That is, in place of the first clutch 11 and the second clutch 12 in the first embodiment, a clutch 101 is used.
An operation of this embodiment will be explained. First of all, regarding the auxiliary convey system, as shown in FIG. 38, in a condition that the auxiliary convey roller 3 is positioned below the sheet stacking tray 13, when the drive pulley 30 is rotated in a direction shown by the arrow A in FIG. 38, the driving force is transmitted to the auxiliary convey pulley 23 and the idle pulley 27 via the belt 9. First of all, the support member 7 is rotated in an anti-clockwise direction around the support shaft 22 until it is stopped by the normal rotation stopper 42, and then the auxiliary convey pulley 23 and the idle pulley 27 and accordingly the auxiliary convey roller 3 are rotated. In order to permit such rotation, it is necessary to reduce a rotational resistance of the support member 7 as small as possible, because, in a condition that the belt 9 is stopped, the auxiliary convey pulley 23 or the idle pulley 27 must be subjected to the rotational resistance to an extent that the support member 7 can be kept stationary at any position within a rotational range of the support member 7 without being rotated by the weight of the auxiliary convey roller 3, auxiliary convey pulley 23, pivot shaft 25, idle pulley 27, pivot shaft 26 and support member 7 themselves.
In this embodiment, as shown in FIG. 39, a cushion member 102 for applying the load (resistance) to the rotation of the auxiliary convey pulley 23 is disposed between the auxiliary convey roller 3 and the support member 7. Further, the position of the normal rotation stopper 42 is so selected that the auxiliary convey roller 3 is subjected to the pressure from the sheet hold-down member 43 at the same time when the auxiliary convey roller 3 is protruded above the sheet stacking tray 13. Further, since an outer peripheral length defined by the auxiliary convey pulley 23, idle pulley 27 and drive pulley 30 is substantially constant within the rotational range of the support member 7, the belt 9 is prevented from being tensioned too great or too small.
Next, a reading operation will be explained with reference to a flow chart shown in FIG. 40.
An operator sets the sheets S on the sheet stacking tray 13 (step F1). When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to the control portion 55. On the basis of a signal from the control portion 55, a separation gear 103 is rotated by the drive motor 31 (step F3). As a result, since the driving force is transmitted to the separation roller 5 and the separation shaft 6 via a spring clutch 101, thereby rotating these elements 5, 6 in the direction shown by the arrow A in FIG. 38, the drive pulley 30 connected to the separation shaft 6 is also rotated in the direction A, thereby conveying the sheet S to the separation portion by the auxiliary convey roller 3.
By the way, when the operator sets the sheets S on the sheet stacking tray 13, if the sheets S are inserted at a speed slower then a peripheral speed of the auxiliary convey roller 3, the sheets S are pulled by the auxiliary convey roller 3; whereas, if the sheets S are inserted at a speed faster than the peripheral speed of the auxiliary convey roller 3, the auxiliary convey roller 3 is driven by the movement of the sheets S, so that the auxiliary convey roller 3 is rotated faster than a speed given by the drive motor 31. As a result, since a length of the belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 is increased and a length of the belt 9 between the pulley 27 and the drive pulley 30 is decreased, the support member 7 is rotated in the clockwise direction in FIG. 38. Consequently, since the auxiliary convey roller 3 is lowered, the sheets S are not caught by the auxiliary convey roller 3, thereby preventing the damage of the sheets S. Thereafter, when the operator stops the insertion of the sheets S, the auxiliary convey roller 3 conveys the sheets S. Incidentally, the rotation of the support member 7 is regulated by the reverse rotation stopper 41 so that the support member 7 is not excessively rotated in the clockwise direction.
The control portion 55 controls so that the drive motor 31 is rotated until a first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the separated sheet S is detected by the aligning sensor 20 (step F4) and then the drive motor is stopped.
The image density and resolving power during the reading of image information are set by the operator, and the reading is started (step F5). The drive motor 31 is rotated by the signal from the control portion 55 to rotate the separation gear 103 (step F6). The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). In this case, since the peripheral speed of the convey roller pair 16 is faster than the peripheral speed of the separation roller 5, the separation roller 5 is driven by the movement of the sheet, with the result that the spring clutch 101 is disengaged, thereby stopping the separation shaft 6, so that the separation gear 103 is rotated idly.
Further, although the auxiliary convey roller 3 is also driven by the movement of the sheet, since the separation shaft 6 is stopped, the length of the belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 is increased and the length of the belt 9 between the pulley 27 and the drive pulley 30 is decreased, with the result that the support member 7 is rotated in the clockwise direction in FIG. 38, thereby lowering the auxiliary convey roller 3 to a position where the auxiliary convey roller 3 is not driven by the movement of the sheet. In this way, the auxiliary conveying force is not transmitted to the sheet.
Thereafter, when the trailing end of the sheet S has passed through the separation roller 5, the separation roller 5 is not driven by the movement of the sheet, with the result that the spring clutch 101 is engaged, thus restoring the auxiliary conveying force again.
The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9). When the reading of the sheet is completed, if there is a next sheet S (step F10), the program returns to the step F7, so that the reading is continued, and, when all of the sheets S are read, the program goes to a step F11. The drive motor 31 is stopped by the signal from the control portion 55 (step F11), and the reading operation is ended.
With the arrangement as mentioned above, it is possible to automatically transmit or interrupt the auxiliary conveying force with respect to the sheet by the single motor without any complicated control and to improve the setting of the sheets.
FIG. 41 shows a first alteration of the fourth embodiment, wherein an auxiliary convey motor 104 serves to drive the auxiliary convey system alone, and the drive pulley 30 is independently driven by the auxiliary convey motor 104. As shown in a block diagram of FIG. 42, the drive motor 31, sheet detection sensor 15, aligning sensor 20, reading portion 17 and auxiliary convey motor 104 are controlled by a control portion 55 of a facsimile system and the like. The reading operation in this case is as shown in a flow chart of FIG. 43.
The operator sets the sheets S on the sheet stacking tray 13 (step F1). When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to the control portion 55. On the basis of a signal from the control portion 55, the drive motor 31 and the auxiliary convey motor 104 are rotated (step F3). The operation of the auxiliary convey system in this case is the same as that in the fourth embodiment. The control portion 55 controls so that the drive motor 31 is rotated until a first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the sheet S is detected by the aligning sensor 20 and then the drive motor is stopped (step F4).
The image density and resolving power during the reading of image information are set by the operator, and the reading is started (step F5).
The drive motor 31 is rotated by the signal from the control portion 55 (step F6) to rotate the separation roller 3, the convey roller pair 16 and the discharge roller pair 19. The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9).
When the reading of the sheet is completed, if there is a next sheet S (step F10), the program returns to a step F11, and, when all of the sheets S are read, the program goes to a step F14. The next sheet S is separated by the separation roller 5 and the separation member 46. However, in this case, since the auxiliary conveying force does not act, the next sheet is not sometimes conveyed. Thus, when the sheet S is not conveyed (i.e., when the sheet is not detected by the aligning sensor 20) after a predetermined time has been elapsed (step F11), the program goes to a step F12; whereas, if detected, the program goes to a step F13.
The auxiliary convey motor 104 is rotated by the signal from the control portion 55 (step F12) to provide the auxiliary conveying force. The operation of the auxiliary convey system in this case is the same as that of the fourth embodiment. If the auxiliary convey motor 104 is rotated by the signal from the control portion 55, this motor is stopped (step F13), thereby interrupting the auxiliary conveying force, and the program returns to the step F7 to continue the reading. The drive motor 31 is stopped by the signal from the control portion 55 (step F14), and all of the reading operations are finished.
With the arrangement as mentioned above, it is possible to properly control the influence of the auxiliary conveying force upon the separation means with a simple construction.
FIGS. 44 to 46 show other examples of the means for applying the load to the rotation of the auxiliary convey pulley 23. In FIG. 44, the reference numeral 105 denotes a leaf spring secured to the support member 7 and adapted to apply the load to the rotation of the auxiliary convey pulley 23 by abutting against the auxiliary convey pulley 23.
Further, in FIG. 45, the reference numeral 10 denotes a friction plate a rotation of which is regulated and which is urged against the end of the auxiliary convey pulley 23 to apply the load to the rotation of the auxiliary convey pulley 23.
Further, in FIG. 46, the reference numeral 108 denotes a spring clutch which is wound around collars 109 secured to the auxiliary convey roller 3 and the support member 7 and which generates an appropriate loosing torque when the auxiliary convey roller 3 is rotated in the sheet conveying direction, thereby applying the load to the rotation of the auxiliary convey pulley 23. Incidentally, as mentioned above, these elements 105, 106, 108 may apply the load to the rotation of the pulley 27.
Next, a fifth embodiment of the present invention will be explained with reference to FIGS. 47 to 49. In this embodiment, the construction of the clutches and the control of the control portion differ from those in the first embodiment. That is, clutches 110, 112 are used in place of the first clutch 11 and the second clutch 12 in the first embodiment.
First of all, regarding the auxiliary convey system, when the drive pulley 30 is rotated in a direction shown by the arrow A in FIG. 47, the driving force is transmitted to the auxiliary convey pulley 23 and the pulley 27 via the belt 9. The support member 7 is rotated in the anti-clockwise direction around the support shaft 22 until it is stopped by the normal rotation stopper 42, and then the auxiliary convey pulley 23 and the pulley 27 and accordingly the auxiliary convey roller 3 are rotated. In order to permit such rotation, it is necessary to reduce a rotational resistance of the support member 7 as small as possible, because, in a condition that the belt 9 is stopped, the auxiliary convey pulley 23 or the pulley 27 must be subjected to the rotational resistance to an extent that the support member 7 can be kept stationary at any position within a rotational range of the support member 7 without being rotated by the weight of the auxiliary convey roller 3, auxiliary convey pulley 23, pivot shaft 25, pulley 27, pivot shaft 26 and support member 7 themselves.
In this embodiment, as shown in FIG. 48, a cushion member 102 for applying the load (resistance) to the rotation of the auxiliary convey pulley 23 is disposed between the auxiliary convey roller 3 and the support member 7. Further, the position of the normal rotation stopper 42 is so selected that the auxiliary convey roller 3 is subjected to the pressure from the sheet hold-down member 43 at the same time when the auxiliary convey roller 3 is protruded above the sheet stacking tray 13.
To the contrary, when the drive pulley 30 is rotated in a direction shown by the arrow B in FIG. 47, the driving force is transmitted to the auxiliary convey pulley 23 and the pulley 27 via the belt 9, with the result that, as shown in FIG. 47, the support member 7 is firstly rotated in the clockwise direction around the support shaft 22 until it is stopped by the reverse rotation stopper 41. The position of the reverse rotation stopper 41 is selected so that the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 in this case. Further, since an outer peripheral length defined by the auxiliary convey pulley 23, idle pulley 27 and drive pulley 30 is substantially constant within the rotational range of the support member 7, the belt 9 is prevented from being tensioned too great or too small.
Next, a reading operation will be explained with reference to a flow chart shown in FIG. 49.
An operator sets the sheets S on the sheet stacking tray 13 (step F1). When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion (not shown). On the basis of a signal from the control portion, a separation gear 111 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 47) by the drive motor 31 (step F3). In this case, although the separation roller 5 is not rotated because of the disengagement of the spring clutch 110, since the driving force is transmitted to the separation shaft 6 via a spring clutch 112, thereby rotating the shaft 6 in the direction shown by the arrow B, the drive pulley 30 connected to the separation shaft 6 is also rotated in the direction B, thereby immediately lowering the auxiliary convey roller 3 even if this auxiliary convey roller is positioned above the sheet stacking tray. Thus, the setting ability of the sheets is improved.
The control portion controls so that drive motor 31 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 and then the motor 31 is stopped (step F4). The image density and resolving power during the reading of image information are set by the operator, and the reading is started (step F5).
The separation gear 111 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 on the basis of the signal from the control portion (step F6). In this case, although the spring clutch 112 is disengaged, since the driving force is transmitted to the separation roller 5 and the separation shaft 6 via the spring clutch 110, thereby rotating these elements in the direction A, the drive pulley 30 is also rotated in the direction A, thus lifting the auxiliary convey roller 3. At the same time, the auxiliary convey roller 3 is rotated in the anti-clockwise direction to convey the sheets S to the separation portion.
The sheets S are separated one by one by the separation roller 6 and the separation member 46 (step F7). The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F8). In this case, since the peripheral speed of the convey roller pair 16 is faster than that of the separation roller 5, the separation roller 5 is driven by the movement of the sheet, with the result that the spring clutch 110 is disengaged, thus stopping the separation shaft 6 and permitting the idle rotation of the separation gear 111. Further, although the auxiliary convey roller 3 is also driven by the movement of the sheet, since the separation shaft 6 is stopped, a length of the belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 is increased and a length of the belt 9 between the pulley 27 and the drive pulley 30 is decreased, thereby rotating the support member 7 in the clockwise direction in FIG. 47 to lower the auxiliary convey roller 3 to a position where the auxiliary convey roller is not driven by the movement of the sheet. In this way, the auxiliary conveying force is interrupted.
Thereafter, when the trailing end of the sheet S has passed through the separation roller 5, the separation roller 5 is not driven by the movement of the sheet, with the result that the spring clutch 110 is engaged, thereby restoring the auxiliary conveying force. That is, the auxiliary convey roller 3 is lifted.
The image information on the sheet S is read by the reading portion 17 (step F9). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F10). When the reading of the sheet is completed, if there is a next sheet S (step F11), the program returns to the step F7 to continue the reading, and, when all of the sheets S are read, the program goes to a step F12.
The drive motor 31 is stopped by the signal from the control portion (step F12), and all of the reading operations are finished.
Next, a first alteration of the fifth embodiment will be explained. Incidentally, in this alteration, only the controlling method differs from that of the fifth embodiment.
A reading operation will be described with reference to a flow chart shown in FIG. 50.
The sheets S are set on the sheet stacking tray 13 by the operator (step F1). In this case, the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 so that the sheets S can easily be set by the operator. When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion.
On the basis of the signal from the control portion, the separation gear 111 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 (step F3). In this case, although the spring clutch 112 is disengaged, since the driving force is transmitted to the separation roller 5 and the separation shaft 6 via the spring clutch 110, thereby rotating these elements 5, 6 in the direction shown by the arrow A, the drive pulley 30 connected to the separation shaft 6 is also rotated in the direction A, whereby the auxiliary convey roller 3 conveys the sheets S to the separation portion. The control portion controls so that the drive motor 31 is rotated until the first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the separated sheet S is detected by the aligning sensor 20 and then the drive motor is stopped (step F4).
The image density and resolving power during the reading of image information are set by the operator, and the reading is started (step F5).
On the basis of the signal from the control portion, the separation gear 111 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 (step F6). The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). In this case, since the peripheral speed of the convey roller pair 16 is faster than that of the separation roller 5, the separation roller 5 is driven by the movement of the sheet, with the result that the spring clutch 110 is disengaged, thereby stopping the separation shaft 6 and permitting the idle rotation of the separation gear 111. Further, although the auxiliary convey roller 3 is also driven by the movement of the sheet, since the separation shaft 6 is stopped, a length of the belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 is increased and a length of the belt 9 between the pulley 27 and the drive pulley 30 is decreased, thereby rotating the support member 7 in the clockwise direction in FIG. 47 to lower the auxiliary convey roller 3 to a position where the auxiliary convey roller is not driven by the movement of the sheet. In this way, the auxiliary conveying force is interrupted.
Thereafter, when the trailing end of the sheet S has passed through the separation roller 5, the separation roller 5 is not driven by the movement of the sheet, with the result that the spring clutch 110 is engaged, thereby restoring the auxiliary conveying force.
The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9). When the reading of the sheet is completed, if there is a next sheet S (step F10), the program returns to the step F7 to continue the reading, and, when all of the sheets S are read, the program goes to a step F11.
On the basis of the signal from the control portion, the separation gear 111 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 47) by the drive motor 31 (step F11). In this case, although the separation roller 5 is not rotated because of the disengagement of the spring clutch 110, since the driving force is transmitted to the separation shaft 6 via the spring clutch 112, thereby rotating the separation shaft in the direction B, the drive pulley 30 is also rotated in the direction B to lower the auxiliary convey roller 3 below the sheet stacking tray 13. Thus, the sheets S can easily be set by the operator. The control portion controls so that the drive motor 31 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 and then the drive motor is stopped (step F12). Thereafter, all of the reading operations are finished.
In this alteration, when the apparatus is in a stand-by condition after a power source is turned ON, or when the apparatus is returned to the stand-by condition after the abnormal condition such as the sheet jam or the sheet removal during the operative condition, the drive motor 31 is controlled so that the drive pulley 30 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 47), thereby lowering the auxiliary convey roller 3 below the sheet stacking tray 13.
Next, a second alteration of the fifth embodiment will be explained. In this second alteration, during the auxiliary convey roller 3 is being lowered after a group of readings have been finished, when a group of next sheets are set, the auxiliary convey roller 3 is lifted. A reading operation will be described with reference to a flow chart shown in FIG. 51.
The sheets S are set on the sheet stacking tray 13 by the operator (step F1). In this case, the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 so that the sheets S can easily be set by the operator. When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion. On the basis of the signal from the control portion, the separation gear 111 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 (step F3). In this case, although the spring clutch 112 is disengaged, since the driving force is transmitted to the separation roller 5 and the separation shaft 6 via the spring clutch 110, thereby rotating these elements 5, 6 in the direction shown by the arrow A, the drive pulley 30 connected to the separation shaft 6 is also rotated in the direction A, whereby the auxiliary convey roller 3 conveys the sheets S to the separation portion.
The control portion controls so that the drive motor 31 is rotated until the first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the separated sheet S is detected by the aligning sensor 20 and then the drive motor is stopped (step F4). The image density and resolving power during the reading of image information are set by the operator, and the reading is started (step F5). On the basis of the signal from the control portion, the separation gear 111 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 (step F6).
The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). In this case, since the peripheral speed of the convey roller pair 16 is faster than that of the separation roller 5, the separation roller 5 is driven by the movement of the sheet, with the result that the spring clutch 110 is disengaged, thereby stopping the separation shaft 6 and permitting the idle rotation of the separation gear 111. Further, although the auxiliary convey roller 3 is also driven by the movement of the sheet, since the separation shaft 6 is stopped, a length of the belt 9 between the auxiliary convey pulley 23 and the drive pulley 30 is increased and a length of the belt 9 between the pulley 27 and the drive pulley 30 is decreased, thereby rotating the support member 7 in the clockwise direction in FIG. 47 to lower the auxiliary convey roller 3 to a position where the auxiliary convey roller is not driven by the movement of the sheet. In this way, the auxiliary conveying force is interrupted.
Thereafter, when the trailing end of the sheet S has passed through the separation roller 5, the separation roller 5 is not driven by the movement of the sheet, with the result that the spring clutch 110 is engaged, thereby restoring the auxiliary conveying force.
The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9). When the reading of the sheet is completed, if there is a next sheet S (step F10), the program returns to the step F7 to continue the reading, and, when all of the sheets S are read, the program goes to a step F11.
On the basis of the signal from the control portion, the separation gear 111 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 47) by the drive motor 31 (step F11). In this case, although the separation roller 5 is not rotated because of the disengagement of the spring clutch 110, since the driving force is transmitted to the separation shaft 6 via the spring clutch 112, thereby rotating the separation shaft in the direction B, the drive pulley 30 is also rotated in the direction B to lower the auxiliary convey roller 3 below the sheet stacking tray 13. Thus, the sheets S can easily be set by the operator.
When the fact that the sheets S are set during the reverse rotation of the drive motor 31 is detected by the sheet detection sensor 15 (step F12), the program is returned to the step F3 on the basis of the signal from the control portion, thereby rotating the drive motor 31 in the normal rotation direction again, and then the program goes to a step F13. The control portion controls so that the drive motor 31 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 (step F13) and then the drive motor is stopped. And, all of the reading operations are finished.
In this alteration, when the apparatus is in the stand-by condition after the power source is turned ON, or when the apparatus is returned to the stand-by condition after the abnormal condition such as the sheet jam or the sheet removal during the operative condition, the drive motor 31 is controlled so that the drive pulley 30 is rotated in the reverse rotation direction (shown by the arrow B in FIG. 47), thereby lowering the auxiliary convey roller 3 below the sheet stacking tray 13. However, on the way, when the fact that the sheets S are set is detected by the sheet detection sensor 15, the drive pulley 30 is rotated in the normal rotation direction (shown by the arrow A in FIG. 47) by the drive motor 31 so that the sequence after the step F3 in FIG. 51 is effected.
Next, a sixth embodiment of the present invention will be explained. This embodiment has the same construction as that of the first alteration of the fourth embodiment, but the control thereof differs from that of the first alteration of the fourth embodiment.
A reading operation is as shown in a flow chart of FIG. 52.
The sheets S are set on the sheet stacking tray 13 by the operator (step F1). When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion. On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the reverse rotation direction so that the auxiliary convey roller 3 is lowered below the sheet stacking tray 13 (step F3). The control portion controls so that the auxiliary convey motor 104 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 (step F4) and then the motor is stopped.
The image density and resolving power during the reading of the image information are set by the operator, and the reading is started (step F5). 0n the basis of the signal from the control portion, the drive motor 31 is rotated (step F6) to drive the separation roller 5, paired convey rollers 16 and paired discharge rollers 19. The sheets S are separated one by one by the separation roller 5 and the separation member 46. In this case, however, since the auxiliary conveying force does not act (the auxiliary convey roller 3 is not lifted by the rotation of the motor 31), the sheets S are not sometimes conveyed. Thus, when the sheet S is not conveyed (i.e., when the sheet S is not detected by the aligning sensor 20) after a predetermined time has been elapsed, the program goes to a step F8; whereas, if detected, the program goes to a step F9 (step F7).
On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the normal rotation direction so that the auxiliary convey roller 3 is lifted above the sheet stacking tray 13, thereby providing the auxiliary conveying force (step F8). When the auxiliary convey motor 104 is rotated in the normal rotation direction by the signal from the control portion, this motor is stopped, thereby interrupting the auxiliary conveying force. The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F10). The image information on the sheet S is read by the reading portion 17 (step F11). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F12).
When the reading of the sheet is completed, if there is a next sheet S, the program returns to the step F7 to continue the reading, and, when all of the sheets S are read, the program goes to a step F14 (step F13). On the basis of the signal from the control portion, the drive motor 31 is stopped (step F14), and all of the reading operations are finished.
With the arrangement as mentioned above, it is possible to improve the setting ability of the sheets with a simple construction.
Next, a first alteration of the sixth embodiment will be explained with reference to a flow chart shown in FIG. 53.
The sheets S are set on the sheet stacking tray 13 by the operator (step F1). In this case, the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 so that the sheets S can easily be set by the operator. When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion. On the basis of the signal from the control portion, the drive motor 31 and the auxiliary convey motor 104 are rotated in the normal rotation (step F3). The control portion controls so that the drive motor 31 and the auxiliary convey roller 104 are rotated until the first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the separated sheet S is detected by the aligning sensor 20 and then these motors are stopped (step F4).
The image density and resolving power during the reading of the image information are set by the operator, and the reading is started (step F5). 0n the basis of the signal from the control portion, the drive motor 31 is rotated (step F6) to drive the separation roller 5, paired convey rollers 16 and paired discharge rollers 19. The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9).
When the reading of the sheet is completed, if there is a next sheet S, the program returns to a step F11, and, when all of the sheets S are read, the program goes to a step F14 (step F10). The next sheet S is separated by the separation roller 5 and the separation member 46. In this case, however, since the auxiliary conveying force does not act (regarding the next sheet), the sheets S are not sometimes conveyed. Thus, when the sheet S is not conveyed (i.e., when the sheet S is not detected by the aligning sensor 20) after a predetermined time has been elapsed, the program goes to a step F12; whereas, if detected, the program goes to a step F13 (step F11).
On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the normal rotation direction, thereby providing the auxiliary conveying force (step F12). When the auxiliary convey motor 104 is rotated in the normal rotation direction by the signal from the control portion, this motor is stopped, thereby interrupting the auxiliary conveying force, and the program returns to the step F7 to continue the reading (step F13). On the basis of the signal from the control portion, the drive motor 31 is stopped. On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the reverse direction (step F15). The control portion controls so that the auxiliary convey motor 104 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 and then the motor is stopped (step F16). And, all of the reading operations are finished.
With this arrangement, when the apparatus is in the stand-by condition after the power source is turned ON, or when the apparatus is returned to the stand-by condition after the abnormal condition such as the sheet jam or the sheet removal during the operative condition, the drive pulley 30 is rotated in the reverse rotation direction, and the auxiliary convey motor 104 is controlled so as to lower the auxiliary convey roller 3 below the sheet stacking tray 13.
Next, a second alteration of the sixth embodiment will be explained. A reading operation in this case is as shown by a flow chart of in FIG. 54.
The sheets S are set on the sheet stacking tray 13 by the operator (step F1). In this case, the auxiliary convey roller 3 is positioned below the sheet stacking tray 13 so that the sheets S can easily be set by the operator. When the sheet S is detected by the sheet detection sensor 15 (step F2), a signal is sent from the sensor to a control portion. On the basis of the signal from the control portion, the drive motor 31 and the auxiliary convey motor 104 are rotated in the normal rotation (step F3). The control portion controls so that the drive motor 31 and the auxiliary convey roller 104 are rotated until the first sheet S is separated by the separation roller 5 and the separation member 46 and the leading end of the separated sheet S is detected by the aligning sensor 20 and then these motors are stopped (step F4).
The image density and resolving power during the reading of the image information are set by the operator, and the reading is started (step F5). 0n the basis of the signal from the control portion, the drive motor 31 is rotated (step F6) to drive the separation roller 5, paired convey rollers 16 and paired discharge rollers 19. The separated sheet S is conveyed to the reading portion 17 by the pair of convey rollers 16 (step F7). The image information on the sheet S is read by the reading portion 17 (step F8). Then, the sheet S is discharged by the pair of discharge rollers 19 (step F9).
When the reading of the sheet is completed, if there is a next sheet S, the program returns to a step F11, and, when all of the sheets S are read, the program goes to a step F14 (step F10).
The next sheet S is separated by the separation roller 5 and the separation member 46. In this case, however, since the auxiliary conveying force does not act (regarding the next sheet), the sheets S are not sometimes conveyed. Thus, when the sheet S is not conveyed (i.e., when the sheet S is not detected by the aligning sensor 20) after a predetermined time has been elapsed, the program goes to a step F12; whereas, if detected, the program goes to a step F13 (step F11). On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the normal rotation direction, thereby providing the auxiliary conveying force (step F12). When the auxiliary convey motor 104 is rotated in the normal rotation direction by the signal from the control portion, this motor is stopped, thereby interrupting the auxiliary conveying force, and the program returns to the step F7 to continue the reading (step F13). On the basis of the signal from the control portion, the drive motor 31 is stopped (step F15). On the basis of the signal from the control portion, the auxiliary convey motor 104 is rotated in the reverse direction (step F15). When the fact that the sheets S are set during the reverse rotation of the auxiliary convey motor 104 is detected by the sheet detection sensor 15, the program is returned to the step F3 by the signal from the control portion, thereby rotating the drive motor 31 and the auxiliary convey motor 104 in the normal rotation direction again; whereas, if not detected, the program goes to a step F17 (step F16).
The control portion controls so that the auxiliary convey motor 104 is rotated in the reverse rotation direction until the support member 7 is abutted against the reverse rotation stopper 41 and then the motor is stopped. And, all of the reading operations are finished.
With this arrangement, when the apparatus is in the stand-by condition after the power source is turned ON, or when the apparatus is returned to the stand-by condition after the abnormal condition such as the sheet jam or the sheet removal during the operative condition, the drive pulley 30 is rotated in the reverse rotation direction, and the auxiliary convey motor 104 is controlled so as to lower the auxiliary convey roller 3 below the sheet stacking tray 13. However, on the way, when the fact that the sheets S are set is detected by the sheet detection sensor 15, the drive pulley 31 is rotated in the normal rotation direction by the auxiliary convey motor 104, whereby the sequence after the step F3 in FIG. 52 is effected.
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The present invention provides a sheet supplying apparatus with a feeding device for feeding out sheets tacked on a stacking tray, a separator for separating the sheets fed out by the feeding device one by one and for conveying the separated sheet, a drive device for driving the separator and the feeding device, sheet conveyer for conveying the sheet separated by the separator at a speed faster than a conveying speed of the separator, a rotation controller for transmitting one direction rotation of the drive device to a drive shaft of the drive device to cause the separation and conveyance of the sheet and for interrupting the transmission of the one direction rotation to the drive shaft so that the separator is driven by the movement of the sheet due to the difference in conveying speed thereby causing such interruption by the driven movement of the separator, support for supporting the feeding device for shifting movement between a sheet convey position and a non-convey position and for shifting the feeding device to the sheet convey position, and a retractor for retracting the feeding device to the non-convey position when the one direction rotation to the drive shaft is interrupted.
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BACKGROUND TO THE INVENTION
This invention relates to franking machines for printing a postal franking on mail items.
Franking machines are provided with a print drum carrying printing elements which can be selectively set to print a desired value of postal franking and the date of franking. After setting the printing elements, printing is effected by rotating the drum and pressing an envelope or label against the drum, and the printing elements carried thereby, by means of a pressure roller. Prior to engaging the envelope, the printing elements pass through an inking station where ink is applied to the printing elements. Rotation of the drum together with the pressure roller causes the envelope to be fed therebetween and to be ejected after printing of the franking.
The printing elements, carried by the drum, for printing the franking value are set by means of thumb wheels or similar mechanical setting devices or by means of electromechanical means controlled by electrical signals located on a body of the franking machine. Mechanical linkages are provided between the mechanical setting devices, or the electromechanical means, and the printing elements to enable the printing elements to be set to print the value desired. Due to the need for rotation of the print drum and the printing elements carried thereby relative to the body of the machine, the mechanical linkages have to be constructed to set and maintain the printing elements at the desired settings while at the same time allowing rotation of the print drum. Consequently the mechanical linkages are complex and as a result are expensive to manufacture. Furthermore the linkages occupy a large space within the machine which causes difficulty in manufacturing a compact franking machine.
It is an object of the present invention to provide a construction of franking machine which is less costly to manufacture and is more compact.
SUMMARY OF THE INVENTION
According to the present invention a franking machine comprises a base member; and a rotatable member mounted for rotation on said base member; said rotatable member including a print drum carrying selectively settable printing elements; input means settable to a desired value of franking to be printed; print element setting means operative in response to said input means to set the printing element to the value set by the input means; accounting means responsive to the setting of the input means to register the selected franking value, to carry out accounting functions in relation to said selected franking value and to generate a control signal if the selected franking value is permitted to be printed; and control means normally inhibiting rotation of the rotatable member on said base member and operative in respone to said control signal to free the rotatable member for rotation to effect printing of the selected franking value.
Preferably the accounting means comprises electronic logic circuits operative to register the selected franking value and the accumulated sum of franking values printed by the machine. The accounting means may also include registers to record a value of credit available for use in franking. The rotatable member may carry display means for displaying items of data such as for example the selected franking value, the accumulated sum of franking values printed by the machine, the credit available and instruction data relating to operation of the machine. Such instruction data may indicate malfunctions of the machine and, where the electronic circuits are powered by a battery carried in the rotatable member, may indicate whether the battery voltage lies within specified limits.
The rotatable member may be rotated for printing a franking value by manually operated drive means or by an electrically powered motor mounted on the base member.
The manually operable drive preferably includes a lever rotatable about a pivot on said base member; drive means mechanically coupling said lever to the rotatable member, said drive means being operative upon movement of said lever from a rest position to an operated position to rotate said rotatable member to effect printing of the selected franking value and said drive means including a one way clutch operative to permit return of said lever from said operated position to said rest position without rotation of said rotatable member.
Preferably the franking machine includes feed means coupled to said lever; said feed means being operated by return of said lever from the operated position to the rest position to eject from the machine a mail item upon which the selected franking value has been printed.
The accounting and control means may be powered by an electric battery housed within the rotatable member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an overall view of a manually operable franking machine.
FIG. 2 is a sectional view on the line 2--2 of FIG. 1 of one side casing illustrating the construction of a manual drive for the franking machine.
FIG. 3 is a sectional view on the line 3--3 of FIG. 1 of the other side casing illustrating a mail item ejection drive.
FIG. 4 is a diagrammatic representation of the rotatable member of the franking machine.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, a manually operable franking machine comprises a base member 10 having first and second side casings 11,12. A printing platform 13 extends out from the side casing 12. A rotatable member comprising an enclosure 14 and a print drum 15 is supported for rotation in bearings in the side casings 11,12, The print drum 15 is secured by a hollow shaft 16 (FIG. 3) extending through the end casing 12 to the enclosure 15 of the rotatable member.
The print drum 15 carries within it a set of four printing elements 17 for printing franking values. These elements are in the form of printing wheels selectively settable by rotation thereof to print a selected value. The upper part of the enclosure consists of a facia plate 18 carrying four keys 19 corresponding respectively to the four printing elements. The keys are slidable to set a selected desired value of franking. Adjacent each key are indicia indicating the value to which the key is set. Additionally the facia plate 18 carries a multidigit digital display 20 to enable values registered in an accounting device and other information to be displayed.
Each of the print wheels 17 has a toothed wheel rotatable therewith which is engaged by a toothed rack on one end of a bar 21. The bars 21 extend through the hollow shaft 16 into the interior of the enclosure 14 where they are connected respectively to stems of the keys 19. Because the enclosure 14 is rigidly joined to the print drum 15 and rotates with the drum, the bars 21 can be connected directly to the key stems without the need for the provision of any intermediate connections permitting relative rotation as is the situation in known franking machines. As a result little space is taken up in the enclosure 14 by the elements needed for setting the print wheels. The key stems extend through slots in the facia plate 18 allowing limited sliding motion of the keys. As will be appreciated, sliding movement of a key causes the bar connected thereto to be moved longitudinally relative to the rotatable member and hence the toothed rack at the end of the bar produces rotation of the associated print wheel to a setting in which it will print the value selected by the position of the key 19. In order to prevent erroneous setting of the print wheels to positions intermediate correct positions, a detent rack extends within the enclosure 14 adjacent the key stems and the key stems resiliently engage the rack when released. Prior to sliding a key, it is necessary to depress the key to disengage the stem from the rack and when the key has been moved to a selected position, the stem re-engages the rack when the key is released. Means are provided to sense that the key stem is engaged with a detent in the rack and to inhibit operation of the machine until all the key stems are properly engaged with the rack.
Referring to the diagram of FIG. 4, located within the enclosure 14 is an electronic assembly consisting of one or more printed circuit boards carrying electronic components for carrying out accounting operations and for controlling operation of the machine. Sensors 41 are provided for each key 19 to provide electrical signals representing the digital values to which each key has been set and these signals are input as the selected franking value to the accounting logic circuitry 42. Registers 43 are provided for storing the selected franking value, the accumulated sum of franking values previously printed and where appropriate, a register for storing the current value of credit available for use in franking. The electronic circuitry is powered by an electric battery 44 housed within the enclosure 14.
The enclosure may conveniently be of generally cylindrical form. For security, the enclosure is sealed to prevent unauthorised access to its interior. However the battery may be housed in an accessible compartment 45 in the enclosure to permit replacement of the batteries. Those parts of the electronic circuitry such as the registers 43 for storing values for accounting purposes may be implemented by non volatile semiconductor storage elements or those parts of the circuitry may be powered by a separate long life battery 46 within the sealed part of the enclosure. The processor circuitry is arranged to check that the battery voltage lies within preset limits prior to permitting a franking operation to be effected.
In order to carry out a postal franking operation an envelope is placed on the platform 13 and the rotatable member is rotated so as to move the print wheels past an inking device (not shown) and to feed the envelope between the drum and a pressure roll. Hence the drum 15 with the print wheels 17 rolls along the face of the envelope and prints the franking thereon.
Normally rotation of the rotatable member is prevented by means of a catch 47 engaging between the base 10 and the enclosure 14 of the rotatable member. When it is desired to effect a franking operation, the keys are set to the required franking value and the processing circuitry carries out a check to establish that the keys are correctly set relative to the detent rack, that the required value is a permitted value, that the accumulated franking value does not exceed a predetermined limit and that there is sufficient credit for this currently required franking. If the results of these checks are satisfactory an output signal is generated to release the catch 47 and thereby permit the rotatable member to be rotated. After rotation to effect a franking, the catch re-engages to prevent further franking until the checks have been repeated.
Rotation of the rotatable member may be effected by an electricmotor housed in the base 10, however for low cost compact machines it is preferred to provide for manual operation. This is provided by a bar 22 which extends across the front of the machine between the side casings 11, 12. As shown in FIGS. 2 and 3, the bar 22 is supported in casing 11 by a lever 23 pivoted at 24 and in casing 12 by a lever 25 pivoted at 26. The lever 23 is formed with an arc of teeth 27 which mesh with a first pinion 28 freely rotatable on an axis concentric with the axis of rotation of the rotatable member. The first pinion 28 meshes with a second pinion 29. A third pinion 30 concentric with and coupled to the second pinion 29 meshes with a fourth pinion 31 concentric with the axis of rotation of the first pinion 28 and coupled to the rotatable member. By applying manual pressure to depress the bar 22, the bary may be moved down to the position indicated at 32. This movement causes the arc of teeth 27 to rotate the first pinion 28 counterclockwise and hence the second and third pinions 29, 30 rotate clockwise and the latter drives the fourth pinion 31 in a counterclockwise direction. As a result, the rotatable member is rotated in a direction to effect printing of a franking. A spring, not shown, returns the bar to its initial position when it is released. In order to prevent the rotatable member being rotated in the reverse direction during this movement of the bar 22, a one way clutch is provided in the coupling between the second and third pinions 29, 30 or between the fourth pinion 31 and the rotatable member. The ratios between the teeth of the pinions are so chosen that a single depression of the bar to the position 32 will result in rotation of the rotatable member through an angle of 360 degrees.
Generally the circumference of the printing drum 15 will be less than the length of an envelope on which the franking is to be printed. As a result, after a single rotation of the print drum, the trailing end of the envelope lies beneath the print drum. In order to eject the envelope from the machine a pressure roll 33 located under the platform 13 is driven, in a counterclockwise direction as seen in FIG. 3, during the return movement of the bar 22. This is accomplished by a belt and pulley drive in the casing 12. A pulley 34 is secured to the shaft of the pressure roll 33 and is driven by belt 35 passing round pulley 36 freely rotatable on the casing 12. A further belt 37 passes around a further groove in the pulley 36 and a further pulley 38 also freely rotatable on the casing 12. The further belt 37 is secured to the lever 25 at a point 39. During downward movement of the bar 22 the attachment of the belt 37 to the lever 25 causes clockwise rotation of the pulleys and this would produce undesired clockwise rotation of the pressure roll 33. To prevent this undesired rotation of the pressure roll 33, the pressure roll 33 is coupled to the pulley 34 through a one way clutch. During movement of the bar 22 to its initial position, the belt 37 is driven by its connection with the lever 22 and causes counterclockwise rotation of the pulleys. This direction of rotation of the pulley 34 causes the one way clutch to transmit drive to the pressure roll 33. The pressure roll is resiliently biassed against the print drum so as to press the envelope against the print elements. The pressure roll also bears against further small rollers immediately adjacent the print drum so that when the print drum ceases rotation, when the bar 22 reached position 32, the gripping of the envelope between the pressure roll 33 and the further small rollers permits the envelope to be fed out of the machine by the rotation of the pressure roll during return movement of the bar 22.
A drum cover 40 (FIG. 10 provides a safe-guard to security of access to the print wheels 17. The cover is locked in a closed position during rotation of the print drum and in addition there is a further inner cover (not shown) to protect the print wheels when the drum 15 is in its normal rest position.
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A low cost compact franking machine includes a rotatable member comprising a print drum and an enclosure housing print element setting means and electronic accounting means, the rotatable member being rotatably mounted on a base. The rotatable member may be rotated by a manually operated lever coupled to the rotatable member through a one-way clutch to allow the lever to return to a rest position without rotation of the rotatable member, the return of the lever may operate a feed to eject a franked mail item.
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BACKGROUND OF THE INVENTION
[0001] There are several industrial applications known in the art, either of electrolytic or electrometallurgical nature, that make use of anodes whereupon the evolution of a gaseous product takes place, whose achievement constitutes in some cases the primary aim of the process (as for the chlorine evolved in the electrolysis of alkaline chlorides or hydrochloric acid). In other cases, the evolved gas is just a by-product of the reaction (as in the case of oxygen evolved in the processes of metal cathodic electroplating, typical of the galvanic industry). In both cases, one of the primary objects in the realisation of electrodes for gas evolution, and in particular of the anodes, is the high electrochemical activity, that must allow operating with the lowest possible overvoltages in order to increase the global energetic efficiency of the process. It is therefore common practice, also in case the gas developed on an electrode surface is just a by-product, to carry out such reactions on catalytic surfaces. Since the materials with the best electrocatalytic properties are very expensive, such a category fundamentally comprising the platinum group metals and their oxides, their employment is common only as thin superficial layers, coated on a conductive matrix. In particular, it is widely known to the experts in the art the use of metallic substrates coupling good current conduction and corrosion resistance features, having at least one surface coated with a thin layer of noble metals and/or oxides or alloys thereof; embodiments of this kind are for instance disclosed in U.S. Pat. Nos. 3,428,544, 3,711,385, and many others. The corrosion resistance of the metallic substrate is a very critical parameter especially in the case of electrodes destined to function as anodes, where the aggressiveness of the electrolytes is further favoured by the electrochemical working potential. For this reason, the anodes for industrial electrolytic and electrometallurgical applications are preferably realised starting from substrates of valve metals, that is metals resisting to corrosion for being protected by a thin superficial film of inert oxide. Among these, the metal most often employed is by far titanium, for reasons of cost and workability. The electrochemical characteristics of titanium matrixes coated with noble metal oxide based catalysts are normally considered more than satisfying as gas evolving anodes for nearly all the industrial electrochemical applications. Conversely their lifetime, especially in the most critical working conditions (highly aggressive electrolytes, very high current density, etc.) constitutes, in many cases, a problem not yet fully solved, although a rich literature exists by now testifying some fundamental progresses in this field. A high duration of the electrodes is a fundamental condition for the industrial success of the electrochemical applications, not only because, in case of deactivation, a new electrochemical coating, inherently expensive both in terms of material and of manpower, must be deposited, but also for the missed production associated to the plant shut-downs required for the replacement of the electrodes. Since the noble metals used in the formulation of electrocatalytic coatings are per se immune from corrosion in the usual operating conditions, the prevailing cause of deactivation consists in the local detachment of the coating from the substrate, with consequent corrosion or passivation of the latter. Such detachment is favoured from the gas evolution itself, due to the mechanical action of the bubbles formed on the surface, and the phenomenon is further emphasised at high current density. In particular, in some electrometallurgical applications with anodic oxygen evolution, for instance in the zinc plating of sheets for use in the car industry or in the production of thin copper sheets for use in the electronic industry, anodic current densities exceeding 15 kA/m 2 are reached.
[0002] A further factor of instability for the adhesion of the coating to the substrate may derive from the porosity of the former, allowing the infiltration of electrolyte in direct contact with the unprotected metallic matrix. In such cases, in particular if zones of detachment exist even if microscopic, passivation of the substrate can occur, with formation of an often scarcely conductive oxide interposed between substrate and electrocatalytic coating, without the physical detachment of the latter taking place. To obtain a sufficient anchoring of the electrocatalytic coating to the substrate the usefulness of conferring a certain roughness to the substrate itself, for instance by means of a sandblasting treatment, or by controlled etching with a corrosive agent, is widely known since the origin of this type of electrodes. The superficial roughness favours the mutual penetration of the substrate and the catalyst, obtained through the thermal treatment of a precursor applied to the substrate in form of a paint. In the case of titanium for instance, abrasive treatments with sand, sand mixed to water or corundum, and etching with hydrochloric acid are well established; such procedures allow obtaining electrodes which find a possible use in some industrial applications, notwithstanding the necessity of submitting the electrodes to a still rather frequent periodic reactivation. Among the most penalised applications, the electrometallurgical processes with anodic evolution of oxygen should again be cited, especially in case operation at current density higher than 10 kA/m 2 is required. Also for low current density processes however, as in the case of electrowinning in acidic environment of metals from solutions deriving from ore dissolution, problems subsist, albeit of a different kind; among them, the impurities always present in the electrolytic baths, some of which have an extremely deleterious effect on the passivation of titanium matrixes. A classic example is given by fluoride ions, capable of complexing titanium thereby destroying the protective film with consequent attack of the underlying metallic matrix, especially in zones where micro-defects in the adhesion of the electrocatalytic coating to the substrate are already present.
[0003] The employment of intermediate coatings with adequate characteristics of corrosion inhibition to be interposed between metallic substrate and electrocatalytic coating has been thus repeatedly proposed under different forms, so that the corrosive attack in correspondence of the always present micro-defects is stopped in correspondence of such barrier. An example of intermediate coating, based on ceramic oxides of valve metals, is disclosed in the European Patent EP 0 545 869, but several other types of intermediate coating, mainly based on transition metal oxides, are known in the art.
[0004] The definition of the optimal roughness parameters of electrodic matrixes suited to receive an electrocatalytic coating is for instance disclosed in the European Patent EP 0 407 349, assigned to Eltech Systems Corporation, USA, wherein it is specified that, in order to achieve a good quality adhesion of the coating itself, it is necessary to impart a superficial average roughness not lower than 250 microinches (about 6 micrometres), with an average of at least 40 peaks per inch (on the basis of a profilometer upper threshold of 400 microinches, that is about 10 micrometres, and of a lower threshold of 200 microinches, that is about 8 micrometres).
[0005] The finding disclosed in EP 0 407 349 constitutes a step forward toward the definition of an electrode with improved characteristics of potential and duration, however it is apparent to the experts of the field that such a high roughness, obtained by means of a severe generalised attack of the surface of chemical or mechanical nature, requires the deposition of catalytic layers of a certain thickness to obtain a sufficiently homogeneous covering. It is a customary practice, known to the experts in the art, the deposition of catalytic layers, independent of the presence of intermediate protective layers, having an overall noble metal loading well higher than 10 g/m 2 , preferably comprised between 20 and 30 g/m 2 , for all of the cited industrial (electrolytic and electrometallurgical) applications. In the absence of this, the duration of the anodes for gas evolution is still largely insufficient.
[0006] Also the subsequent patent application US-2001-0052468-A1, which provides superimposing a microrough profile on a macrorough profile quite similar to the one of EP 0 407 349, although giving electrodes with superior lifetime characteristics also in the absence of intermediate coatings, is fundamentally directed to electrodes with consistent noble metal loadings (24 g/m 2 in the examples). Such high loadings of noble metal are onerous from an economical standpoint, and in some cases they are not acceptable at all: this is especially the case of the primary electrometallurgical applications (electrowinning and similar), where the added value of the products is not high enough to justify such elevated investment costs.
OBJECTS OF THE INVENTION
[0007] Under one aspect, it is an object of the present invention to provide an electrode substrate overcoming the inconveniences of the prior art.
[0008] Under another aspect, it is an object of the present invention to provide an electrode substrate allowing to produce gas evolving anodes with improved characteristics of catalytic coating adhesion.
[0009] Under a further aspect, it is an object of the present invention to provide an electrode substrate allowing to produce a gas evolving anode with improved lifetime characteristics even in presence of catalytic coatings with a reduced noble metal loading with respect to the prior art.
[0010] Under a further aspect, it is an object of the present invention to provide a method for the preparation of an electrode substrate and of a relevant gas evolving anode with improved lifetime characteristics.
DESCRIPTION OF THE INVENTION
[0011] Under a first aspect, the invention consists of a valve metal, preferably titanium, electrode substrate, with low average roughness, in particular with average roughness Ra comprised between 2 and 6 micrometres, deriving from a localised attack on the crystal grain boundary.
[0012] Under another aspect, the invention consists of a gas evolving anode for electrochemical applications consisting in a low roughness valve metal substrate, said roughness deriving from a localised attack of the crystal grain boundary, coated with a catalytic layer based on noble metals, with an optional protective layer, wherein said coating layers penetrate within the grain boundaries subjected to the localised attack thereby covering the substrate, and wherein the final roughness after the coating application is preferably comprised between 2 and 4.5 micrometres.
[0013] Under a further aspect, the invention consists of a method for the preparation of a valve metal electrode substrate with low roughness, said roughness deriving from a localised attack of the crystal grain boundary, comprising a step of controlled etching in a medium achieving a specific attack of the grain boundary; for this purpose, the preferred medium for the attack is sulphuric acid, but other acids such as perchloric add and mixtures of hydrofluoric acid with nitric acid are suited to the scope.
[0014] With the aim of facilitating the understanding of the invention, the latter will be described making reference to the annexed figures, which have merely an exemplifying purpose and do not intend by any means to constitute a limitation of the same.
DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 shows a top view of the surface of a titanium electrode substrate according to the invention.
[0016] FIGS. 2, 3 and 4 show top views of surfaces of electrode substrates not in accordance to the specifications of the present invention.
[0017] FIG. 5 shows a cross-section of the electrode substrate of the invention of FIG. 1 .
[0018] FIG. 6 shows a cross-section of the electrode surface of FIG. 3 not in accordance with the specifications of the present invention.
[0019] FIG. 7 shows a cross-section of an anode of the invention obtained by application of a catalytic coating to the substrate of FIGS. 1 and 5 .
[0020] FIG. 8 shows a cross-section of an anode obtained by application of a catalytic coating to the substrate of FIGS. 3 and 6 not in accordance with the specifications of the present invention.
[0021] FIG. 9 shows a cross-section of another anode obtained by application of a catalytic coating to an electrode substrate not in accordance with the specifications.
DETAILED DESCRIPTION OF THE INVENTION
[0022] Contrarily to the teachings of the prior art, it has been surprisingly observed that the anodes for gas evolution in electrochemical applications may be advantageously obtained from substrates of valve metal, preferably titanium, having a very low average roughness, in any case not higher than 6 micrometres, provided such roughness is conveniently localised. In particular, the optimal roughness must be obtained starting from a metal of not too high average crystal grain size (preferably comprised between 20 and 60 micrometres, and even more preferably between 30 and 50 micrometres), by means of a preferential attack of the external surface localised in correspondence of the boundary of said crystal grains. In a preferred embodiment, the crystal grain boundary of a titanium surface to be used as electrode substrate is attacked, for instance by means of an acid etching, removing a certain amount of metal in correspondence of the boundaries of the grains without completing the detachment of the latter. In a still more preferred embodiment, such attack which removes metal from the superficial crystal grain boundary has a depth of penetration corresponding to about half the depth of the grain, and in any case comprised between 20 and 80% of such depth. As previously said, the anode substrate of the invention is preferably made of pure or alloyed titanium, but the use of other valve metals such as tantalum, niobium or zirconium is also possible. The substrate of the invention can assume any geometry known in the field of gas evolving anodes, and can be for instance a solid or perforated sheet, an unflattened or flattened expanded sheet, a net or other type of mesh, or a rod or bar or combination of rods or bars; other particular geometries are however possible, depending from the requirements of the case. The anode substrate of the invention is usually coated with one or more coating layers, known to the experts in the art. In particular, the application of one or more layers for the protection from corrosion and passivation phenomena is possible; in this case, very thin layers based on transition metal oxides are usually employed, but other types of protective coatings are possible. For the use in practical applications of industrial interest, for instance as regards the anodes for oxygen or chlorine evolution, the substrate is preferably coated, usually in the external part contacting the electrolyte, with a catalytic coating, preferably based on mixtures of noble metals or oxides thereof. Contrarily to the teachings of the prior art, the substrate of the invention permits to obtain an anode with optimal duration characteristics, also in high current density electrochemical processes, with very thin electrocatalytic coatings, limiting the noble metal content even below 10 grams per square metre of active area. It has been surprisingly found, eventually, that the localised attack at the crystal grain boundary, producing a characteristic profile with valleys (negative peaks in the roughness profile) that are distanced in a sufficiently uniform fashion and have a controlled penetration depth, is sufficient to grant an optimum anchoring of the coating penetrating said valleys, also in the absence of a high average roughness, obtained with a generalised surface attack. It has been even surprisingly found that in the absence of an excessive average roughness, the loading of the coating necessary to uniformly cover the surface of the substrate is pretty much lower, and that the anode can, in this case, operate for long times before passivation or in general deactivation phenomena occur, also with a noble metal content of the outermost coating limited to 5-10 g/m 2 . Without wishing to bind the extent of the instant invention to any particular theory, it can be hypothesised that, as regards the titanium or other valve metal substrates, the adhesion characteristics of the catalytic or protective coatings are mainly associated to the availability of anchoring points at the grain boundaries, and that the roughness characteristics deriving from a heavy generalised attack create valleys that are rather useless from the adhesion standpoint, moreover entailing the onus of having to be filled with a sufficient amount of coating in order to avoid leaving scarcely covered and easily passivatable zones. A complete anode of the invention, obtained by covering the disclosed substrate with a catalytic coating and an optional protective coating of the state of the art, presents an extremely smooth surface, thus exhibiting an average roughness typically comprised between 2 and 4.5 micrometres.
[0023] The preferred method for the preparation of the anode substrate of the invention comprises an etching step with a corrosive medium capable of selectively attacking the grain boundary; the methods disclosed in the state of the art to obtain high roughness provide sandblasting steps, thermal treatments, depositions of matter with plasma technique or etchings with corrosive media such as hydrochloric acid, that are capable of imparting roughness profiles more or less controlled, but in any case generalised on the whole surface. It has been surprisingly found that sulphuric acid mixtures under controlled conditions, and preferably sulphuric acid as an aqueous solution having a concentration of 20 to 30% by weight at a temperature comprised between 80 and 90° C., are able to achieve a specifically localised attack on the grain boundary of valve metals, and in particular of titanium. In a preferred embodiment, the etching bath in which the electrode substrate of the invention is treated also contains a passivating agent, capable of adjusting the attack velocity in such a manner that the desired roughness profile is confidently obtained, that is achieving the grain boundary attack with a penetration depth not lower than 20% of the grain average dimension (so as to avoid obtaining an insufficient anchoring of the coating) and not higher than 80% thereof (so as to avoid causing the detachment of the smallest grains). The presence of a passivating species increases the selectivity of the grain boundary attack, but even more importantly renders the attacking time uniform, allowing an excellent control of the process. As the passivating species, it is possible for example to add iron under ionic form; however the titanium itself, dissolving in the etching bath, can achieve an optimal passivation above a certain concentration (indicatively 2 g/l). It is thus convenient to add a corresponding amount of titanium under ionic form to the etching bath before utilising the same, without exceeding too much as an etching bath containing more than 30 g/l of titanium loses its efficacy and has to be considered substantially exhaust. Titanium may be added as a salt, or more conveniently by dissolving titanium metal until reaching the optimum concentration. It is also possible to use a sulphuric acid bath to etch titanium destined to other uses, and start employing the same for the electrode substrates of the invention once the titanium concentration that allows a suitable control is reached. The substrate of the invention may also be prepared with a sulphuric acid bath free of passivating species, however an accurate check of the roughness profile in subsequent times must be effected, until reaching the required specification. With an etching bath of sulphuric acid in aqueous solution of concentration comprised between 20 and 30% by weight at a temperature comprised between 80 and 95° C., containing titanium at a concentration comprised between 2 and 30 g/l or another equivalent passivating agent, the etching treatment must be preferably carried out for a time comprised between 45 and 120 minutes.
[0024] To obtain even more reproducible results, it is preferable to carry out, before etching, a thermal annealing treatment, which in the case of titanium is generally effected between 500 and 650° C. for a time sufficient to uniform the crystal grain size. In order to effect a thorough cleaning of the substrate, especially as regards the renovation of deactivated electrode structures, it is preferable in some cases to carry out also a sandblasting pre-treatment, for instance with corundum or other aluminium oxide based material.
EXAMPLE 1
[0025] A sheet of titanium grade 1 according to ASTM B 265, 0.2 cm thick, with a surface of 35 cm×35 cm, was degreased with acetone, rinsed with demineralised water, air-died and subjected to an annealing thermal treatment at 570° C. for two hours; at the end of the treatment, it was studied at the optical microscope to check the crystal grain average size, which resulted to be 35 micrometres. The sheet was then immersed in an aqueous bath of sulphuric acid, prepared from acid of pure grade for batteries, at a concentration of 25% by weight and at a temperature of 87° C. At the beginning of the treatment, the bath contained 5 g/l of titanium expressed as metal. The treatment was protracted for 60 minutes. At the end of the etching, the washed and dried sample was subjected to a roughness determination with a profilometer; the average roughness, measured with a profilometer with a bandwidth around the middle line Pc of ±8 micrometres, resulted to be 4 micrometres.
[0026] A new optical microscope investigation, wherefrom the picture reported as FIG. 1 has been obtained, was then effected. A localised attack along the crystal grain boundary is clearly evidenced; the surface of said grains appears instead as virtually not affected by the attack.
[0027] The same sample was cut in half to observe its section, reported as FIG. 5 ; a very regular surface profile is evidenced, with valleys corresponding to the grain boundary. The two resulting halves of the sheet were finally painted to apply a state-of-the-art protective layer, based on titanium and tantalum oxides in 35:65 atomic ratio, and a catalytic coating of iridium and tantalum oxides with a total noble metal loading expressed as sum of elemental Ta and Ir of 5 g/m 2 .
[0028] The samples so activated had a residual average roughness of 3.5 micrometres; FIG. 7 shows the section one of these activated samples. The penetration of the catalytic coating inside the valleys corresponding to the crystal grain boundary of the substrate is clearly evidenced.
COUNTER EXAMPLE 1
[0029] The test of example 1 was repeated with an identical sheet, the only variation being that the etching treatment was protracted for just 30 minutes. FIG. 2 shows a picture of its surface after etching, evidencing an inhomogeneous situation, with wide zones not subjected to any attack, alongside others where a slight grain boundary attack is evidenced.
[0030] The sheet was activated in the same way as the samples of example 1.
COUNTER EXAMPLE 2
[0031] The test of example 1 was repeated with an identical sheet, the only variation being that the etching treatment was protracted for 180 minutes. FIG. 3 shows a picture of its surface after etching, displaying a localised attack on the grain boundary exceeding 80% of the grain average thickness, so that a good percentage of grains results to be completely removed, and the metal is attacked beyond the first row of grains. The same sample was cut in half to observe its section, reported as FIG. 6 , wherein a totally irregular profile is evidenced, with several completely removed grains. The two resulting halves of the sheet were painted in the same way as in example 1; FIG. 8 shows a section of an activated sample, evidencing as the coating leaves some grains almost uncovered, penetrating however, in other zones, beyond the whole thickness of the crystal grain which thereby results to be completely embedded. It is evident to the experts in the art as the uncovered zones are immediately subjected to passivation, while those were entirely embedded crystal grains are easily subjected to detachments especially in case of gas evolution at high current density.
COUNTER EXAMPLE 3
[0032] The test of example 1 was repeated, the only variation being that the etching was effected in commercial grade hydrochloric acid, as a 22% by weight aqueous solution, at the boiling point, according to a widespread state-of-the-art procedure. FIG. 4 shows a picture of its surface after etching, evidencing a generalised attack, which doesn't allow visualising the boundary of the single grains.
[0033] The sheet was activated in the same way as the samples of example 1.
COUNTER EXAMPLE 4
[0034] The test of example 1 was repeated, the only variation being that the etching was effected with sulphuric acid free of titanium or other passivating species. FIG. 9 shows a picture of a section thereof after activation, evidencing as the coating leaves some grains almost uncovered, penetrating however, in other zones, beyond the whole thickness of the crystal grain which thereby results to be completely embedded. The situation is practically equivalent, in other words, as that of counter example 2, indicating how, in the absence of passivating species, sulphuric acid presents a much higher aggressiveness than under regimen conditions, with an adequate titanium concentration already present in the bath.
EXAMPLE 2
[0035] The activated samples of example 1 and of counter examples 1, 2, 3 and 4 were subjected to a life test, consisting in making them work as oxygen evolving anodes at high current density in an aggressive electrolyte, determining the time of deactivation expressed as hours of operation needed to raise the electrode overpotential beyond a predetermined value. The lifetime value obtained in this kind of tests, where the process conditions are extremely exasperated with respect to those of the industrial practice, allows extrapolating with a certain reliability the duration in the effective processes they are destined to, as known to the experts of the field.
[0036] The lifetime test employed consists in using the sample as gas evolving anode in a test cell that performs the electrolysis of a sulphuric acid aqueous solution with a concentration of 150 g/l at 60° C., and at an anodic current density of 30 kA/m 2 . As the counter electrode, a hydrogen evolving zirconium cathode of large area is employed, which works thereby at very low current density and whose potential is substantially constant during the test. The initial cell voltage in these conditions is about 4.5 V; the anode is considered deactivated when such cell voltage reaches a conventional value of 8 V.
[0037] The two activated samples of example 1 (anodes obtained from the substrate of the invention) showed, in these conditions, a duration comprised between 3500 and 4200 hours; the two samples of counter example 1 (substrate insufficiently attacked in the etching phase) showed a duration comprised between 900 and 1080 hours; the two samples of counter example 2 (substrate excessively attacked in the etching phase) showed a duration comprised between 1500 and 1900 hours; the two samples of counter example 3 (substrate etched in hydrochloric acid and subjected to a generalised attack) showed a duration comprised between 1200 and 1400 hours; the samples of counter example 4 (substrate excessively attacked in the etching phase) showed a duration comprised between 1700 and 1850 hours.
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The invention concerns an anode for gas evolution in electrochemical applications comprising a titanium or other valve metal substrate characterized by a surface with a low average roughness, having a profile typical of a localized attack on the crystal grain boundry. The invention further describes a method for preparing the anodic substrate of the invention comprising a controlled etching in a sulfuric acid solution.
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PRIORITY INFORMATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/370,911 on Apr. 8, 2002.
FIELD OF THE INVENTION
[0002] The field of this invention is downhole gravel packing systems with valves to isolate or allow access to various zones.
BACKGROUND OF THE INVENTION
[0003] Typically in a gravel pack completion, a sump packer is set in the wellbore and the formation is perforated. The perforating gun is removed and a gravel packing assembly is installed. Screens are part of this assembly as is a crossover tool. The crossover tool is secured to a production packer. The production packer is set and the crossover is configured in a manner so as to allow pumping gravel through the production packer and into the annular space outside the screens. Return fluid, less the deposited gravel, goes through the production screen and through a valve in a blank pipe in the screen, back through the crossover and out the annular space above the set production packer. A closing tool on a wash pipe in a concentric string closes the sliding sleeve valve(s) when the crossover tool is pulled at the conclusion of the gravel packing operation. After the production string is run to the production packer, access to the formation involved using wireline or service string through the production packer to shift the internally mounted sliding sleeve(s) to gain access to the producing formation. This technique is illustrated in U.S. Pat. No. 5,609,204 assigned to OSCA Inc. of Lafayette, La.
[0004] Subsequently, OSCA developed internally mounted pressure actuated circulating valves. These valves were integral to each section of screen assembly. Each screen section had a non-perforated base pipe having the sliding sleeve valve over a series of openings mounted on each screen section. For long screen intervals, numerous valves were required to be manipulated for full access to the producing zone. The close fit of these sliding sleeves to the screen and the integral construction did not allow for alternate access to the formation if such valves refused to open. Additionally, the integral construction with the screen sections precluded removal of such valves if they failed to operate without removing the entire screen assembly integral to such sliding sleeve valves. The presence of gravel exterior to the screens made it problematic to remove the screen assembly after deposition of the gravel.
[0005] Other commercially available systems from Schlumberger and Weatherford used isolation ball valve systems as opposed to concentric isolation string hookups.
[0006] The present invention seeks to address several limitations in the prior systems. It not only allows access to multiple zones with pressure actuated valves that open after pressure is applied and then removed, but it also allows through the use of a redundant valve, the ability to close off the access to a given layer should that be necessary, while maintaining the capability of re-accessing the zone at a later date. Should the main valves not open in response to application and removal of pressure, the annular gap to the screen allows for access through the blank pipe without damaging the screen. Additionally, by placing the access valves on a removable portion of the inner string, the invention permits removal of the access valve while leaving the screen and surrounding gravel pack in place. The use of this inner string, separate from the screen, also permits the use of systems which manipulate the entire concentric string itself in order to provide alternate flow paths during packing operations. These and other benefits of the invention will become clearer to those skilled in the art from a review of the description of the preferred embodiment and the claims, which appear below.
SUMMARY OF THE INVENTION
[0007] A gravel packing system featuring pressure actuated sliding sleeve valves mounted to an exterior annulus around a blanking pipe for screen sections is disclosed. An internal sliding sleeve valve is provided for subsequent closure of access through the screens. The presence of the annulus between the blanking pipe and the screen permits a backup access through perforating the blanking pipe while not damaging the screen. The sliding sleeve valves that are mounted internally and externally on the blanking pipe are removable apart from the screen section that already has gravel packed around it, if they fail to operate and need repair.
DETAILED DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is an elevation view of the assembly in the run in position;
[0009] [0009]FIG. 2 is the views of FIG. 1 shown in the circulate position;
[0010] [0010]FIG. 3 is the views of FIG. 2 shown in the reverse position;
[0011] [0011]FIG. 4 is the views of FIG. 3 shown in the pull out position;
[0012] [0012]FIG. 5 is the views of FIG. 4 shown in the produce position;
[0013] [0013]FIG. 6 is a split view of the pressure actuated sliding sleeve valve in the open and closed positions;
[0014] [0014]FIG. 7 illustrates the way of getting alternate access through the blanking pipe if the sliding sleeve valve does not operate properly;
[0015] FIGS. 8 - 10 illustrate the pull out feature of the concentric pipe assembly;
[0016] FIGS. 11 - 14 are an alternate to FIGS. 1 - 5 allowing returns by raising the concentric pipe instead of using a sliding sleeve valve adjacent the screen that is closed when the wash pipe is removed with the run-in string.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] The gravel packing assembly of the present invention is illustrated in FIG. 1. A cased wellbore 10 is illustrated with a run in string 12 supporting a setting tool 14 to actuate the packer 16 . A crossover tool 18 is supported from the setting tool 14 and a wash pipe 20 is, in turn, supported off the crossover tool 18 . Down below is a sump packer 22 that has earlier been set in the well, generally before perforations 24 have been made, using a perforating gun of a type well known in the art.
[0018] Suspended from the isolation packer 16 is a frac sleeve valve 26 , which is run in the open position. Below the sleeve valve 26 are tubulars or blank pipe 28 followed by a two-pin sub 30 . The external assembly connected to the two pin sub 30 comprises a tubular 32 followed by a breakaway coupling 34 (seen more easily in the enlarged view in FIG. 8). Shear pin 36 holds coupling 34 together and seal 38 prevents leakage, when the coupling 34 is intact. Below coupling 34 are additional tubulars 40 followed by a screen or screens 42 to a length as required by the depth of the formation producing through perforations 24 . The specific screen construction can vary and many known designs can be used. It is worthy of emphasis that there is an annular gap 44 between the screen 42 and the internal blanking pipe 46 . Continuing on below the screen 42 is a production pipe 48 that sealingly extends into a seal bore 50 in the sump packer 22 .
[0019] Starting on the inside of the two-pin sub 30 is a valve assembly 52 , shown in larger detail in FIG. 6. The valve assembly 52 supports blanking pipe 46 , which has a sliding sleeve valve 54 in it and a seal assembly 56 at its lower end to sealingly engage the production pipe 48 . Sliding sleeve valve 54 is run in open and is subsequently closed when the wash pipe 20 is removed and closure mechanism 58 engages the sliding sleeve valve 54 , as shown in FIG. 4.
[0020] Referring now to FIG. 6, the valve assembly 52 further comprises an internal sliding sleeve 60 having an opening or openings 62 that are in alignment with opening or openings 64 in the tubular 66 . Stated differently, for run in, openings 64 are not obstructed by sliding sleeve 60 but are obstructed by sliding sleeve 67 mounted externally to the tubular 66 . Sliding sleeve 67 has a pair of seals 76 and 78 that span openings 64 and are at unequal diameters such that pressure applied within tubular 66 tends to put an unbalanced force on sliding sleeve 67 moving it in a direction that breaks shear pin 70 while moving in a direction to compress spring 72 . When applied pressure is released, spring 72 moves sliding sleeve 67 until a snap ring 68 expands into groove 80 to lock the sliding sleeve 67 in the open position. Spring 72 is disposed in annular space 74 .
[0021] [0021]FIG. 7 illustrates some back up techniques to deal with the issue of a particular sliding sleeve valve 67 , of which there are preferably one in each producing formation, fails to open with the applied pressure technique just described. The primary backup technique is to remove the wash pipe 20 and the cross-over 18 and run in a shifting tool 82 on slick line or equivalent 84 and operate sliding sleeve 54 back to the open position. It should be remembered that removing the wash pipe 20 causes the closure mechanism 58 to close sliding sleeve 54 . If that doesn't work a mini-perforating tool 86 run in on slick line or equivalent 84 can be positioned in blanking pipe 46 to penetrate only into the annular gap 44 , without risk of doing damage to tubulars 40 in a manner that would allow formation fluid to bypass the screens 42 .
[0022] The operation of the assembly shown in FIGS. 1 - 5 will now be described. As previously stated, the sump packer 22 is run in and set in the cased wellbore 10 . Perforation in the known manner creates perforations 24 . A run in string 12 supports the assembly as previously described until it reaches the perforations 24 . The packer 16 is set. If needed a squeezing operation into perforations 24 can take place. Arrows 88 in FIG. 1 show the flow direction of treatment chemicals as going down the run in string 12 and through crossover 18 into annular space 90 and into the perforations 24 . The position of the crossover 18 in FIG. 1 prevents return flow uphole even though sliding sleeve valve 54 is open at this time.
[0023] Going to FIG. 2, the circulation of gravel outside the screen 42 occurs as a result of a pick up of the cross-over 18 to allow fluid to flow through screen 42 , leaving the gravel behind in annular space 90 . Fluid continues through sliding sleeve valve 54 and down to the bottom of the wash pipe 20 , then up to the cross-over 18 and through it and into the annular space 92 above packer 16 and out to the surface, as shown by arrow 94 .
[0024] When the gravel has been duly deposited, the cross-over 18 is picked up, as shown in FIG. 3, and flow into annular space 92 arrives from the surface to go through the cross-over 18 and back up the run in string 12 . This flow pattern, illustrated by arrows 96 allows the remaining gravel in the system to be flushed out to the surface.
[0025] The next step, shown in FIG. 4, is to pull out the crossover tool 18 and the wash pipe 20 . As a result, the closure mechanism 58 closes sliding sleeve valve 54 . This movement of the crossover tool 18 allows a closure mechanism 98 mounted on it to close frac sliding sleeve valve 26 .
[0026] At this point, shown in FIG. 5, production tubing 100 with a seal assembly 102 is tagged into the packer 16 . Pressure can be applied from the surface through the production tubing 100 and it will communicate to every closed valve assembly 52 in the wellbore. Each valve assembly 52 has a shear pin 70 and the various shear pins at different intervals can be set at different levels. Operating personnel, depending on the amount of pressure applied can open all or some of the valves 67 . As long as pressure is applied, shown as arrow 104 none of the valves 67 will actually be biased to open. This allows the pressure to be progressively raised to a level to break all shear pins 70 before the applied pressure can escape through opening of any of the sliding sleeve valves 67 . If the pressure is subsequently removed from the surface, production starts from the perforations 24 through the opened sliding sleeve valves 67 to the surface through the production tubing 100 , as indicated by arrow 106 .
[0027] FIGS. 8 - 10 illustrate a feature that allows leaving the screens 42 in place while removing the valve assembly 52 with blanking pipe 46 and seal assembly 56 from sump packer 22 . A retrieving tool 108 is run in and engaged to packer 16 before packer 16 is released, as shown in FIG. 8. The detailed portion of FIG. 8 shows what happens after the packer 16 is released and an upward pull breaks shear pin 36 of breakaway coupling 34 . When coupling 34 comes apart, the retrieving tool 108 pulls out valve assembly 52 , blanking pipe 46 , sliding sleeve valve 54 and seal assembly 56 , as shown in FIG. 9. Subsequently a replacement assembly of the same components is run back into the cased wellbore 10 except that a packoff overshot 110 with a seal 112 , which replaces the seal 38 in the breakaway coupling 34 that used to be there, is sealingly connected to the remaining half of the breakaway coupling 34 . The ability to replace this assembly without pulling the screens is an advantage since after gravel packing, the screen 42 may be very difficult to dislodge.
[0028] FIGS. 11 - 14 disclose essentially the same method as FIGS. 1 - 5 except that sliding sleeve valve 54 has been eliminated. The closure mechanism 58 on the wash pipe 20 now will have a different purpose. A telescoping joint 114 is in the retracted position for run in leaving a gap 116 between the seal assembly 56 and the sump packer 22 . In FIG. 11, the crossover 18 is in position to allow a squeeze job into the perforations 24 with no return path available. In FIG. 12, the crossover 18 has been raised allowing return flow through gap 116 as shown by arrows 118 . In this manner the gravel is deposited outside of screen 42 . FIG. 13 shows the crossover 18 raised to allow reversing out the gravel in the system, as previously described. FIG. 14 shows closure mechanism 58 engaging telescoping joint 116 to push it down. This motion also forces the seal assembly 56 down into sump packer 22 to sealingly close off gap 116 . Thereafter, the valve assembly 52 is operated in the manner previously described. The advantage of this variation is to address the concerns of some operators that sliding sleeve valve 54 will not fully close when the wash pipe 20 and its closure mechanism 58 are moved out of the cased wellbore 10 . Different solutions that provide for the requisite open and closed position of gap 116 than the preferred method described above are contemplated within the scope of the invention. The placement of the device that allows the relative movement can vary and the initial position can also be closed for run in so that gap 116 must be created with relative movement after run in.
[0029] When desired to isolate any given formation, a tool can engage the respective sliding sleeve 60 to close off on or more formations through their respective access ports 64 .
[0030] Those skilled in the art will now appreciate that the apparatus and methods described above provide for several advantages over prior systems for gravel packing. The sliding sleeve valves 67 that are disposed in annular gap 44 and on the outside of tubular 66 are far fewer in number for a producing zone than the prior system provided by OSCA and previously described. In fact a single sliding sleeve valve 67 can be used for a single producing zone regardless of its thickness as measured by the screen footage for screen 42 to produce that zone. The construction of the screens used in the OSCA system dictates a sliding sleeve valve for each screen section because of the nature of the flow through the screen. On the other hand, the present invention has a large annular area 44 inside the screen 42 to allow a single set of openings 64 to service an entire producing zone. The present invention allows for backup access through sliding sleeve valve 54 or through perforation of blanking pipe 46 without damage to tubulars 40 due to the presence of annular area 44 , as shown in FIG. 7. Alternatively, as shown in FIGS. 11 - 14 the gap 116 can be employed for production if the valve assembly 52 fails to open.
[0031] he other option is to use the removability feature shown in FIGS. 8 - 10 to replace the valve assembly 52 which failed to open. By providing redundancy through sliding sleeve valves 67 on the outside of tubular 66 and 60 on the inside combined with using as little as one such assembly for a producing zone, there is a greater assurance that a particular zone can be subsequently isolated and re-opened by manipulation of sliding sleeve valve 60 . Additionally, the sliding sleeve valves 67 are in a protected location from circulating fluids in annular gap 44 so that they are more likely to reliably operate when needed.
[0032] The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made without departing from the spirit of the invention.
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A gravel packing system featuring pressure actuated sliding sleeve valves mounted to an exterior annulus around a blanking pipe for screen sections is disclosed. An internal sliding sleeve valve is provided for subsequent closure of access through the screens. The presence of the annulus between the blanking pipe and the screen permits a backup access through perforating the blanking pipe while not damaging the screen. The sliding sleeve valves that are mounted internally and externally on the blanking pipe are removable apart from the screen section that already has gravel packed around it, if they fail to operate and need repair.
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RELATED APPLICATIONS
This application is a continuation of application Ser. No. 10/760,913, filed on Jan. 20, 2004, which is a division of application Ser. No. 10/283,600 filed on Oct. 30, 2002, which issued as U.S. Pat. No. 6,730,333. The specifications of the prior applications are incorporated herein by reference.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[Not Applicable]
MICROFICHE/COPYRIGHT REFERENCE
[Not Applicable]
BACKGROUND OF THE INVENTION
The present invention relates to nutraceutical compositions derived from the fruit of the Garcinia mangostana L. plant, otherwise known as the mangosteen plant. More particularly, the present invention relates to nutraceutical compositions comprising a mixture of the pulp and pericarp of the mangosteen fruit.
BRIEF SUMMARY OF THE INVENTION
The mangosteen tree ( Garcinia mangostana L.) was named after the French explorer Laurent Garcin (1683-1751) and has been cultivated for a considerable time in tropical areas of the world. The tree is presumed to have originated in South-east Asia or Indonesia and has largely remained indigenous to the Malay Peninsula, Myanmar, Thailand, Cambodia, Vietnam, the Sunda Islands, and the Moluccas. Although the mangosteen fruit is highly praised as one of the best tasting of all tropical fruits, it is considered a minor tropical fruit, and the mangosteen tree has largely piqued purely botanical interests over the years.
The mangosteen tree is a slow-growing, smooth evergreen tree that ranges from 5 to 25 meters in height with a flaking black bark that contains a yellow, resinous latex. The mangosteen tree bears fruit when 6 to 20 years old, depending on location, and can continue to yield fruit for up to 100 years. The mangosteen fruit ripens to a dark reddish-violet to black-violet color and is normally smooth or marked with brownish scars. The pericarp, or rind, of the mangosteen fruit is thick, tough, and exudes a bitter yellowish resin. Only about 25 to 30% of the mangosteen fruit consists of the edible pulp or aril, with the remainder comprising the tough, bitter pericarp. Each mangosteen fruit usually varies in weight from 75 to 120 grams and normally contains 2 to 3 well-developed seeds.
Over the years, the mangosteen plant has been used in a number of different ways. The timber is used for cabinets, building materials, fencing and furniture. The pericarp, containing pectin, tannins, resins and a yellow latex, is used in tanning and dyeing leather black. The fruit pulp is mostly used as a dessert, but can also be canned or made into preserves. However, when removing the fruit pulp from the rind, care must be taken to prevent the tannins and resins of the cut pericarp from contacting the fruit pulp. The mangosteen rind, leaves and bark have also been used as ingredients in folk medicine in areas where the plant grows indigenously. The thick mangosteen rind is used for treating catarrh, cystitis, diarrhea, dysentery, eczema, fever, intestinal ailments, itch, and skin ailments. The mangosteen leaves are used by some natives in teas and other decoctions for diarrhea, dysentery, fever, and thrush. It is also known that concoctions of mangosteen bark can be used for genitourinary afflictions and stomatosis.
Some of the medicinal properties of the Garcinia mangostana L. plant have been the subject of pharmacological and clinical studies. These studies have isolated chemical constituents in the mangosteen leaves, wood, pericarp and seed aril, which were found to contain the following biologically active compounds, among others: 1,6-dihydroxy-3-methoxy-2-(3-methyl-2-butenyl)xanthone, 1,5,8-trihydroxy-3-methoxy-2-(3-methyl-2-butenyl)xanthone, maclurin, 1,3,6,7-tetrahydroxy xanthone, 1,3,6,7-tetrahydroxy xanthone-O-β-D-glucoside, chrysanthemin, cyaniding-3-O-β-D-sophoroside, 8-deoxygartanin, 1,5-dihydroxy-2-isopentenyl-3-methoxy xanthone, 1,7-dihydroxy-2-isopentenyl-3-methoxy xanthone, 5,9-di hydroxy-8-methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2(H), 6(H)-pyrano-(3,2,6)-xanthen-6-one, fructose, garcinone A, B, C, D and E, gartanin, glucose, cis-hex-3-enyl acetate, 3-isomangostin, 3-isomangostin hydrate, 1-isomangostin, 1-isomangostin hydrate, kolanone, mangostin, β-mangostin, α-mangostin, mangostin-3,6-di-O-gulcoside, normangostin, sucrose, tannins, BR-xanthone-A, BR-xanthone-B, calabaxanthone demethylcalabaxanthone, 2-(γ,γ-dimethylallyl)-1,7-dihydroxy-3-methoxyxanthone, 2,8-bis-(γ,γ-dimethylallyl)-1,3,7-trihydroxyxanthone, 1,3,5,8-tetrahydroxy-2,4-diprenylxanthone, and mangostanol. Many of these chemical constituents are xanthones, which are biologically active compounds that are receiving increasing interest in pharmacological studies for a variety of health benefits.
However, despite the pharmacological benefits of individual xanthone compounds and the native medicinal uses of the bark, leaves and rind of the mangosteen plant in South-east Asia and Indonesia, a nutraceutical composition containing the holistic benefits of the entire mangosteen fruit, including the fruit pulp and pericarp, is not known. In fact, it is recognized that when preparing the fruit pulp for consumption, care should be taken to separate from the delicious inner fruit pulp the outer pericarp with its resins and tannins, which are traditionally used to treat and stain leathers.
There exists a need in the nutritional arts for a nutraceutical composition that offers the health benefits of the entire mangosteen fruit, including the pulp and the pericarp. There also exists a need for a nutraceutical composition rich in natural xanthones for treating a variety of human ailments and conditions in an efficacious manner. Further, there is a need in the art for a natural xanthone product that is economical to manufacture.
The present invention relates to nutraceutical compositions derived from the fruit of the Garcinia mangostana L., or mangosteen plant. More particularly, the present invention relates to efficacious nutraceutical compositions rich in natural xanthones that include the pulp and the pericarp of the mangosteen fruit. These compositions preferably comprise a mixture of mangosteen fruit pulp and pericarp with selected juice concentrates. In addition, the present invention relates to methods of preparing nutraceutical compositions of Garcinia mangostana L. plant that yield efficacious health supplements rich in natural xanthones. Further, the methods of preparing the mangosteen nutraceutical compositions are economical to operate.
A primary object of the present invention is to provide a nutraceutical composition that contributes to general human wellness and good health through a novel mixture of the pericarp and pulp of the fruit of the Garcinia mangostana L. plant. The effectiveness of this mixture is heightened through the addition of selected juice concentrates in varying amounts.
Another object of the present invention is to provide a nutraceutical composition that offers the holistic benefits of the entire mangosteen fruit and is an efficacious source of natural xanthone compounds.
An additional object of the present invention is to provide an antimicrobial and anti-inflammatory composition containing a therapeutic amount of natural xanthones derived from the Garcinia mangostana L. plant.
A further object of the present invention is to provide a xanthone-rich natural product with antioxidative properties.
Another object of the present invention is to provide a nutraceutical composition of the Garcinia mangostana L. plant with beneficial antibacterial action.
An additional object of the present invention is to provide a process for preparing nutraceutical compositions of the Garcinia mangostana L. plant yielding the holistic benefits of the unique combination of mangosteen fruit pulp and pericarp, either alone or with complementary and enhancing juice concentrates.
Yet another object of the present invention is to provide an economical process for manufacturing nutraceutical compositions of the entire fruit of the Garcinia mangostana L. plant.
The foregoing and other objects, advantages and characterizing features will become apparent from the following description of certain illustrative embodiments of the invention.
While the methods and processes of the present invention have proven to be particularly useful in the area of nutritional health supplements, those skilled in the art can appreciate that the methods and processes can be used in a variety of different applications and in a variety of different areas of manufacture to satisfy a wide-ranging variety of pharmaceutical and medicinal needs.
The above-described features and advantages of the present invention, as well as additional features and advantages, will be set forth or will become more fully apparent in the description that follows and in the appended claims. The novel features which are considered characteristic of this invention are set forth in the attached claims. Furthermore, the features and advantages of the invention may be learned by the practice of the invention, or will be obvious to one skilled in the art from the description, as set forth hereinafter.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
[Not Applicable]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to nutraceutical compositions derived from the Garcinia mangostana L. plant, otherwise known as the mangosteen plant. In particular, the compositions of the invention described herein uniquely provide natural xanthone compounds through the combination of the pulp and pericarp of the mangosteen fruit, along with selected juice and other phytochemical ingredients. The invention also relates to processes for manufacturing the nutraceutical compositions described herein in an economical manner.
It is understood that the terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. It is also understood that, as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural reference, unless the context clearly dictates otherwise. In the disclosure and in the claims, the term “nutraceutical” shall refer to “any compounds or chemicals that can provide dietary or health benefits when consumed by humans or animals.”
Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Preferred methods, compositions, and materials of the present invention are described herein, although any methods and materials similar or equivalent to those described herein can by used in the practice or testing of the present invention. All references cited herein are incorporated by reference in their entirety.
The Garcinia mangostana L. plant, or mangosteen plant, is known for a variety of uses in the areas to which it is indigenous. For example, there are a number of folk medicines in South-east Asia and Indonesia that employ various decoctions of the leaves, root, and bark of the mangosteen plant, as well as of the pericarp of the mangosteen fruit. For example, according to the literature, the thick mangosteen pericarp can be used as an astringent or in various decoctions for treating catarrh, cystitis, diarrhea, dysentery, eczema, fever, intestinal ailments, itch, and skin ailments. Other medicinal uses of the leaves, root and bark would be known to one of skill in the art. Also, the outer pericarp of the mangosteen fruit, which contains pectins, tannins, resins and a yellow latex, is used for treating and staining leather black.
In contrast to the thick outer pericarp, the edible inner pulp of the mangosteen fruit is widely regarded for its exquisite taste. The inner pulp of a single mangosteen fruit usually consists of four to eight juicy, white-colored segments. When preparing the white pulp segments for consumption, care must be taken so as to not stain the pulp segments with the resins and tannins and other matter that oozes out of the cut outer pericarp. The need to keep the delicious white pulp separate from the dark purple, staining, bitter pericarp has long been known to those familiar with the mangosteen fruit.
Xanthones are biologically active plant phenols that naturally occur in a restricted group of plants. The general structure of a xanthone is:
From a biosynthetic standpoint, they are related to the flavonoids, being formed by the condensation of a phenylpropanoid precursor with two instead of three malonyl coenzyme A units. Xanthones possess significant pharmacological properties, including antidepressant, antitubercular, antimicrobial, antiviral, anti-inflammatory, cardiotonic, antileukaemic, antitumor, antiulcer, antihepatotoxic, antiallergenic, and antirhinoviral activities and actions.
Pharmacological and botanical researchers have discovered that the medicinal properties of the mangosteen pericarp can be attributed to natural xanthones contained in the rind. The unrelated plant families Gentianaceae and Gutterferae are largely where naturally occurring hydroxanthones and their methyl ethers are found. The Garcinia mangostana L. plant, which contains a large number of naturally occurring xanthones, belongs within the Gutterferae family of plants.
Recent research has shown that the γ-mangostin compound, a natural xanthone found in the Garcinia mangostana L. plant, inhibits type A and type B monoamine oxidases as well as cyclooxygenase and prostaglandin E 2 synthesis. (Nakatani et al., 63 Biochemical Pharmacology 73-79 (2002)). Under normal conditions in the brain, the levels of prostaglandin E 2 (PGE 2 ) are very low or even undetectable. However, during episodes of tissue inflammation, multiple sclerosis, and AIDS-related dementia, PGE 2 levels rise, and can affect the activities of neurons, glial, and endothelial cells. High levels of PGE 2 also affect microglia/macrophage and lymphocyte functions. It is widely understood that the generation of prostaglandins is associated with inflammation, pain and fever. Cyclooxygenase is the rate-limiting enzyme in prostaglandin production. There are two isoforms of cyclooxygenase (COX), constitutive (COX-1) and inducible (COX-2), which is expressed in response to inflammation stimuli. The xanthone γ-mangostin is found to directly inhibit activity of both COX isoforms as well as PGE 2 synthesis, which makes this xanthone desirable in the treatment of inflammatory conditions as well as symptoms of fever and pain. The nutraceutical compositions of the present invention offer therapeutic amounts of important xanthones, including y-mangostin, from a natural source to provide increased health and general wellness in humans.
In the present invention, it has been discovered that a mixture of the mangosteen pericarp and fruit pulp in a single nutraceutical composition yields surprising health benefits. The efficacy of this xanthone-rich mixture of mangosteen pericarp and pulp is enhanced through the addition of selected juice and phytochemical ingredients, which are believed to synergistically react with the natural xanthone compounds. In a preferred embodiment of the invention, the mixture of mangosteen fruit pulp and pericarp is complemented by the addition of one or more juice concentrates selected from the group consisting of alfalfa juice concentrate, apple juice concentrate, apricot juice concentrate, banana juice concentrate, blueberry juice concentrate, cantaloupe juice concentrate, carrot juice concentrate, celery juice concentrate, cherry juice concentrate, cranberry juice concentrate, grape juice concentrate, grapefruit juice concentrate, green barley juice concentrate, green lettuce juice concentrate, kale juice concentrate, kiwi fruit juice concentrate, orange juice concentrate, papaya juice concentrate, parsley juice concentrate, pear juice concentrate, pear puree, pineapple juice concentrate, prune juice concentrate, raspberry juice concentrate, spinach juice concentrate, strawberry juice concentrate and tomato juice concentrate.
The nutraceutical compositions of the present invention deliver therapeutic amounts of natural xanthone compounds derived from the mangosteen fruit pulp and pericarp mixture. In one embodiment of the present invention, the mixture of mangosteen fruit pulp and pericarp is present in an amount ranging from between 3 and 50%, preferably between 5 and 25%, and most preferably between 10 and 20% of the total weight of mangosteen mixture and selected juice concentrates. In another embodiment of the invention, the nutraceutical composition comprising mangosteen fruit pulp and pericarp is formulated for oral administration. However, the present compositions can be delivered in any form known in the art, such as tablets, capsules, dispersions, solutions, suspensions, transdermal delivery systems, etc. If the mangosteen pericarp and fruit pulp mixture is complemented with selected juice concentrates, then a liquid beverage is a convenient delivery form, but other delivery forms are equally efficacious and would simply require the use of powders or other equivalent forms of the juice concentrates. Tablets or capsule forms of the present nutraceutical compositions can be prepared and coated by methods known to those of ordinary skill in the art. When the nutraceutical compositions of the present invention are presented in liquid beverage form, the ratio of water to mangosteen mixture and selected juice concentrates can be 1:1, preferably 3:1 and most preferably 4:1.
The nutraceutical compositions of the present invention can be produced through large-scale, economical operations. In one embodiment of the invented process, whole fruit from the Garcinia mangostana L. plant is picked and transported to a production facility. The fresh fruit can kept at ambient air temperatures during transportation or it can be frozen, depending on need. The entire mangosteen fruit, including the fruit pulp and pericarp, is then ground into a pulp and pericarp mixture using commercial grinding or mixing equipment. The resulting mixture of mangosteen fruit pulp and pericarp can then be further processed through the addition of one or more of the selected juice concentrates listed above. In preferred embodiments of the beverage form of the invention, the selected juice concentrates and water are then added to the mixture in accordance with the amounts, ranges and ratios specified above. The liquid nutraceutical compositions can then be treated, bottled or packaged for distribution to consumers using a variety of methods known to those of ordinary skill in the art, such as pasteurization, flash pasteurization, sterilization, UHT sterilization, pressure sealing, freezing, freeze drying, irradiating, etc. Dehydrated and other forms of the nutraceutical compositions can also be prepared using standard techniques.
The effectiveness in improving general health and wellness of the nutraceutical mangosteen compositions described herein is demonstrated from the following clinical examples; which are listed for illustrative purposes only and are not meant to be limiting instances of therapeutic use. A therapeutic composition of the mangosteen fruit pulp and pericarp mixture was prepared according to the embodiments described herein. Each subject ingested 3 ounces of the beverage daily for a three week period. The following qualitative results were obtained:
EXAMPLE 1
The subject was a 62-year-old female suffering from chronic back pain, nausea and chronic vertigo. Prior to the study, the pack pain was treated with oral doses of morphine three times a day. After a regiment of the mangosteen nutraceutical composition, the subject experienced improved energy, less nausea and a decrease in the vertigo symptoms.
EXAMPLE 2
The subject was a 56-year-old male suffering from chronic obstructive pulmonary disease, muscle aches, fatigue and dysthemia. After a regiment of the mangosteen nutraceutical composition, the subject experienced improvement in mood, energy and muscle aches in the shoulders and back.
EXAMPLE 3
The subject was a 55-year-old male suffering from irritable bowel syndrome. After a regiment of the mangosteen nutraceutical composition, the subject experienced regularization of bowel movements.
EXAMPLE 4
The subject was a 30-year-old male suffering from chronic neck pain, familial hyperlipidemia, fatigue and insomnia. After a regiment of the mangosteen nutraceutical composition, the subject experienced improved energy and a decrease in low-density lipoproteins.
EXAMPLE 5
The subject was a 52-year-old male suffering from hypokelemia, fatigue and weight gain. After a regiment of the mangosteen nutraceutical composition, the subject experienced improved energy and a normalization of potassium levels.
EXAMPLE 6
The subject was a 63-year-old female suffering from degenerative arthritis, C-difficile colitis, fatigue, decreased appetite hypokelemia, and numbness of the fingers and toes. After a regiment of the mangosteen nutraceutical composition, the subject experienced improvement in colitis, reduction of pain in wrists and hands and a normalization of potassium levels.
EXAMPLE 7
The subject was a 66-year-old male suffering from a severe allergy reaction causing desquamation of palms, fingers, soles of feet and the inside of the mouth and esophagus. After a regiment of the mangosteen nutraceutical composition, the subject was completely cured.
EXAMPLE 8
The subject was a 57-year-old male suffering from malaise, muscle aches, hepatitis, glomerionephritis, diabetes and hyperlipidemia. After a regiment of the mangosteen nutraceutical composition, the subject experienced a 30-point decrease in low-density lipoproteins, a 10-point increase in high-density lipoproteins, improved energy, a 14-pound weight loss and the malaise was eliminated.
EXAMPLE 9
The subject was a 30-year-old male suffering from a chronic dermal rash. After a regiment of the mangosteen nutraceutical composition, the rash was completely eliminated.
EXAMPLE 10
The subject was a 25-year-old female suffering from low energy levels. After a regiment of the mangosteen nutraceutical composition, the subject experienced increased energy.
EXAMPLE 11
The subject was a 28-year-old female suffering from extreme fatigue and depression. After a regiment of the mangosteen nutraceutical composition, the subject experienced a significant increase in energy.
EXAMPLE 12
The subject was a 26-year-old female suffering from irritable bowel syndrome. After a regiment of the mangosteen nutraceutical composition, the subject experienced a decrease in cramping and stool frequency and increased energy.
EXAMPLE 13
The subject was a 32-year-old male marathon runner and iron man competitor. After a regiment of the mangosteen nutraceutical composition, the subject experienced increased energy levels.
EXAMPLE 14
The subject was a 70-year-old female suffering from severe arthritis. After a regiment of the mangosteen nutraceutical composition, the subject experienced complete elimination of arthritic symptoms and increased energy.
The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.
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Nutraceutical compositions derived from the fruit of the Garcinia mangostana L. or mangosteen plant and methods to make the same are provided. The nutraceutical mangosteen compositions employ novel combinations of mangosteen fruit pulp and pericarp, and can be additionally complemented by selected juice concentrates to yield a composition for improving general health and wellness in humans. The methods to make the nutraceutical compositions involve the use of a mixture comprising pericarp and inner pulp from whoe fruit of a Garcinia mangostana L. plant.
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This application is a continuation-in-part of applicants application Ser. No. 11/648,967 same titled filed Jan. 3, 2007 now abandoned which is a continuation-in-part of applicants application Ser. No. 10/718,156 of same title filed Nov. 20, 2003 now abandoned.
BACKGROUND
1. Field
This invention relates to devices for cleaning submerged structural surfaces of water bodies such as the bottoms of swimming pools, spas and the like, and particularly concerns unique structure of a water jet operative vacuum type cleaner for removing and filtering out leaves and other such debris from said structural surfaces.
2. Prior Art
A device of this general type is described in U.S. Pat. No. 6,502,269B1 the disclosure of which is hereby incorporated herein by reference in its entirety. A major problem with the cleaner of this patent is that the water-debris intake of the cleaner is in direct fluid communication with intake of the jet pump. In situations where the pool debris contains organic material such as leaves or small pieces of sticks or the like, the pump intake filer will rapidly clog and render the cleaner inoperative.
Principal objects therefore of the invention are: to provide a water jet vacuum type, pool cleaning device which is easy to use and maintain and which preferably utilizes a battery operated water jet pump which, in normal use, virtually cannot be clogged with pool debris; and to provide such device in a structurally simple design and at an economical cost.
SUMMARY OF THE INVENTION
A water jet vacuum cleaning device for vacuuming debris from a debris field on underwater structural surfaces, said device comprising a housing providing a suction cavity communicating with a debris-water suction inlet formed thru said housing, said device being moveable along said surfaces with said suction inlet being in close proximity to said surfaces, said housing being formed with a debris-water discharge conduit having a debris-water outlet which is surrounded by a mesh filter bag extending outside of said housing for entrapping debris, a water ejector tube mounted in said cavity generally in axial alignment with said discharge conduit and adapted for connection exteriorly of said housing to a source of high pressure water or air or the like which is well above said debris field and isolated from said suction inlet, said ejector tube further having a water ejector end located within said cavity and spaced from a debris-water inlet of said discharge conduit to provide a debris entry gap positioned intermediate of and communicating with said inlet and outlet, whereby when water is ejected from said ejector end across said gap and into said discharge conduit the pressure within said cavity will be reduced sufficiently to suck water-debris from said surfaces and into said discharge conduit for transport to said outlet and therethrough into said filter bag.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and its objects will become further apparent from the drawings herein wherein the various figures are not drawn necessarily to scale or proportion and are intended to facilitate understanding of the invention, and wherein:
FIG. 1 is a side view of the present device in operating position adjacent a pool bottom surface with portions of the housing of the device broken away for clarity;
FIG. 2 is a top view of the present device without the filter bag and taken along line 2 - 2 in FIG. 1 with portions of the housing broken away for clarity;
FIG. 3 is a cross-sectional view taken along line 3 - 3 in FIG. 2 ;
FIG. 4 is a cross-sectional view taken along line 4 - 4 in FIG. 3 and showing flow area as double cross-hatched;
FIG. 5 is a cross-sectional view taken along line 5 - 5 of FIG. 3 and showing flow area as double cross-hatched.
DETAILED DESCRIPTION
Referring to the drawings and with particular reference to the claims herein, the present water jet cleaning device 10 for underwater vacuuming of debris 11 from structural surfaces such as bottom 12 of swimming pools or other water bodies comprises a substantially closed housing 14 formed by a wall generally designated 16 preferably of structural plastic such as PVC, cellulosics, butyrates, polyamides, polyolefin or the like, or metal or ceramic, and providing a suction cavity 18 . This cavity can be of any operator convenient volumetric capacity and configuration, however the configuration shown in the drawings is preferred with a preferred capacity of from about 400 ml. to about 2,500 ml., most preferably from about 1,000 ml. to about 1,500 ml.
A debris-water suction inlet 20 extends thru said wall into said cavity. This inlet is of a typical elongated generally rectangular configuration of, for example, a flow area of about 10 in 2 to about 16 in 2 for a cavity capacity of from about 1,000 to about 1,500 ml. The height of the inlet rim 22 from the surface 12 should be preferably from about ⅛ inch to about inch for best results and this height is maintained, e.g., by a pair of wheels 24 mounted on the housing sides adjacent the inlet.
A debris-water discharge conduit 26 formed by said wall has an exit end 28 surrounded by a mesh filter bag 30 of natural or synthetic fibers or thin flat strips or the like and extending exteriorly of said housing and of any desired capacity for entrapping said debris. The filter bag inlet end is affixed in groove 31 encircling an enlarged filter bag attachment collet 33 into which a removable retaining snap ring or band 35 is secured. This collet is threaded into rim 37 provided by wall 16 . Conduit 26 has an entry end portion 32 opening into said cavity, and further has a flow axis 34 . End portion 32 is depicted in FIG. 3 as a dotted line 36 marking the terminus of the funnel shaped portions 38 of wall 16 . In this regard it also marks the outlet end of suction cavity 18 .
A fluid ejector tube 40 is mounted in cavity 18 and extends thru said wall 16 and has a flow axis 42 , a fluid (water) inlet port 44 on a distal end portion 44 a thereof which is adapted for connection exteriorly of said cavity to a source 46 of high pressure fluid. This tube further has a fluid ejector end or nozzle 48 located within said cavity and spaced from said entry end 32 of said conduit and thus provides a debris entry gap 50 communicating with said entry end. The ejector tube flow axis 42 and the conduit flow axis 34 are in general alignment for maximizing the suction and transport effect of stream 52 indicated as dotted arrow lines. The term “general alignment” means a preferred deviation from true alignment of no more than about 30°, and most preferably no more than about 10°.
The flow area 54 of the exit end 28 of said conduit is from about 1.5 to about 30 times, preferably 5.0-20.0 times the flow area 55 of the ejector end 48 of said tube, whereby when fluid stream 52 is ejected from said ejector end and across said gap 50 and thru said discharge conduit 26 and into said filter bag 30 the pressure within said cavity 18 will be reduced sufficiently to suck water-debris from said surfaces up to and into said stream for transport into said filter bag container without the inlet 45 of said high pressure source (pump) 46 or the inlet 44 of said tube being exposed to said debris. It is noted that the present construction affords a practically obstructionless passageway from inlet 20 to exit 28 for the debris. A filter screen 72 of, e.g., 1/16″ ⅛″ wire mesh covens the inlet 45 of pump 46 .
As can be seen from FIGS. 1 and 3 , the inlet rim 22 of suction inlet 20 lies in an operating plane 68 which is typically just above or within the debris field 11 when the device is in operation. This plane in an exemplary sense and during operation of the device, is only from about ⅛″ to about ½″ above and parallel to the pool floor while, on the dimensioned scale shown in FIGS. 1 and 3 , the axis 70 of water pump 46 which supplies high pressure water to ejector tube 40 is, e.g., from about 2″ to about 8″, preferably from about 2″ to about 5½″ above plane 68 and rim 22 and well above the pool floor and the debris field. The concept behind these exemplary dimensions is that the ejector water from pump 46 comes directly from a section of the pool water which is well above the rim 22 such that there is no real possibility that pump 46 and/or the ejector tube can become clogged by debris. In this regard, lengthy trial runs of cleaning pools with applicant's device have shown that no such clogging with applicant's device occurs. An exemplary 12 volt pump is marketed under the tradename “rule” and has a capacity of 700 GPH.
The various parts or portions such as wall 16 , tube 40 , conduit 26 , the housing 56 of electric battery operated water pump 46 , the attachment collet 33 for the fine mesh filter bag 30 , and the operators handle section 62 may be formed by metal fabrication or as a monolithic structure by plastic injection molding or the like, or these parts may be individually provided and plastic welded or adhesively assembled together to form the device.
Handle 62 shown in FIG. 1 preferably carries the electrical leads 64 which extends upwardly thru handle extension 66 to a battery in the manlier shown for example by the aforesaid U.S. Pat. No. 6,502,269 B1, particularly items 12 and 13 described in column 5 thereof.
In preferred embodiments the specifications given below are desirable, wherein the flow areas of 54 and 55 are as stated, with the proviso that the ratio limits (of areas 54 / 55 ) of 1.5-30.0 should be adhered to for best results.
Structure
Preferred
Most Preferred
Pump 46 capacity
200-2,000 gal/hr
500-1,000 gal/hr
Gap 50 Length
0.5 in.-6.0 in.
1.0 in.-4.0 in.
1/d of inner portion 43
1/1 to 15/1
3/1 to 6/1
Flow Area of 54
0.2 in 2 to 7.0 in 2
0.3 in 2 to 3.0 in 2
Flow Area of 55
0.02 in 2 to 0.4 in 2
0.04 in 2 to 0.2 in 2
Pump Motor
6-24 V.
12-20 V.
Mesh opening dia. of filter
100μ-350μ
150μ-250μ
The best mode known at this time is for the diameter (inside) of 26 to be from about 0.75 in. to about 2.0 in., the diameter (inside) of 40 to be from about 0.125 in. to about 0.5 in., and that the axis 70 of pump 46 be from about 3″ to about 5½″ above rim 22 when the device is of the approximate exemplary dimensions given on the drawings and is in the operating posture shown in FIGS. 1 and 3 .
The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications will be effected with the spirit and scope of the invention.
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A portable vacuuming device for underwater removal of leaves or the like of a debris field from pool bottoms and other structural surfaces, the device employing a water pump to feed a water jet within a suction cavity wherein the water inlet for the pump is exterior to the cavity and to the housing of the device, and is located well above the debris field.
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FIELD OF THE INVENTION
This invention relates to derivatives of azabicyclo octane, the method of making them, and the compositions containing the same and the uses thereof, particularly their pharmaceutical use as inhibitors of dipeptidyl peptidase IV (DPP-IV).
BACKGROUND OF THE INVENTION
Diabetes refers to a disease process derived from multiple causative factors and characterized by elevated levels of plasma glucose or hyperglycemia along with sugar, fat and protein metabolism disorder caused by insulin secretion and/or the action defects. Diabetes is an ancient disease, and due to the human body absolute or relative lack of insulin resulting in increased concentrations of glucose in the blood which largely discharges in urine with more drink, more urine, more food, weight loss, dizziness, weakness and other symptoms.
Dipeptidyl peptidase-IV (DPPIV) is a serine protease which cleaves N-terminal dipeptides from a peptide chain containing, preferably, a proline residue in the penultimate position. Although the biological role of DPPIV in mammalian systems has not been completely established, it is believed to play an important role in neuropeptide metabolism, T-cell activation, attachment of cancer cells to the endothelium and the entry of HIV into lymphoid cells (WO98/19998).
More recently, it was discovered that DPPIV is responsible for inhibiting the secretion of glucagon-like peptide (GLP)-1. More particularly, DPPIV cleaves the amino-terminal His-Ala dipeptide of GLP-1, degrading active GLP-1(7-36)NH 2 into inactive GLP-1(9-36)NH 2 (Endocrinology, 1999, 140: 5356-5363). Under the physiological condition, the half-life of the whole GLP-1 in blood circulation is short, the inactive metabolite from GLP-1 degraded by DPPIV can combine with GLP-1 receptor to antagonize the active GLP-1, so the physiological response to GLP-1 is shortened. The endogenous even exogenous GLP-1 can be entirely protected by the DPPIV inhibitor from being deactivated by DPPIV, and the GLP-1 bioactivity can be significantly increased (5- to 10-fold). Since GLP-1 is a major stimulator of pancreatic insulin secretion and can directly effect on glucose disposal, the DPPIV inhibitor is well useful for treating non-insulin-dependent diabetes mellitus (NIDDM) (U.S. Pat. No. 6,110,949).
SUMMARY OF THE INVENTION
Accordingly, the present invention relates to compounds having formula (I) or pharmaceutically acceptable salts thereof:
wherein:
R is selected from the group consisting of alkyl, cycloalkyl, haloalkyl, aryl, heteroaryl, aminocarbonyl alkyl, amide alkyl, aminocarbonyl alkyl having heterocycle and aminoalkyl, wherein the heterocycle is 5- or 6-membered hetero ring further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, alkylamino, amide group, aminocarbonyl, cyano, alkynyl, alkoxyl, aryloxyl, aminoalkyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen;
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 2 is selected from the group consisting of hydrogen and methyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ; and n is an integer from 0 to 4.
Further, the present invention includes the compounds of formula (IA) or pharmaceutically acceptable salts thereof:
wherein:
R is selected from the group consisting of alkyl, cycloalkyl, haloalkyl, aryl, heteroaryl, aminocarbonyl alkyl, amide alkyl, aminocarbonyl alkyl having heterocycle and aminoalkyl, wherein the heterocycle is 5- or 6-membered hetero ring further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, alkylamino, amide group, aminocarbonyl, cyano, allkynyl, alkoxyl, aryloxyl, aminoalkyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen;
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 2 is selected from the group consisting of hydrogen and methyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 .
Preferably, in the compounds having formula (I) or pharmaceutically acceptable salts thereof, R is the following formula:
wherein R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester;
R 6 and R 7 are each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, allkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen; and
W is C, S or O atom.
Further, the present invention includes the compounds of formula (IB) or pharmaceutically acceptable salts thereof:
wherein R is the the following formula:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester;
R 6 and R 7 are each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen; and
W is C, S or O atom.
Further, the present invention includes the compounds of formula (IC) or pharmaceutically acceptable salts thereof:
wherein R is the following formula:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester;
R 6 and R 7 are each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen; and
W is C, S or O atom.
This invention provides compounds having formula (I) or pharmaceutically acceptable salts, wherein the salts comprise the salts formed with the acids selected from the group consisting of hydrochloric acid, p-toluenesulfonic acid, tartaric acid, maleic acid, lactic acid, methanesulfonic acid, sulfuric acid, phosphoric acid, citric acid, acetic acid and trifluoroacetic acid, preferably, the acids are p-toluenesulfonic acid, hydrochloric acid or trifluoroacetic acid.
In a particularly preferred embodiment, the compounds having formula (I) or pharmaceutically acceptable salts include:
Example No.
Structure
Name
1
cis-5-[2-(2-Cyano- pyrrolidin-1-yl)-2-oxo- ethylamino]-hexahydro- cyclopenta[c]pyrrole- 2-carboxylic acid dimethylamide hydrochloride
2
cis-5-[2-(2-Cyano- pyrrolidin-1-yl)-2- oxoethylamino]-hexa- hydro-cyclopenta[c] pyrrole-2-carboxylic acid methyl ester hydrochloride
3
cis-1-{2-[2-(2-Hydroxy- acetyl)-octahydro- cyclopenta[c]pyrrol-5- ylamino]-acetyl}- pyrrolidine-2-carbonitrile hydrochloride
4
cis-1-{2-[2-(Piperidine-1- carbonyl)-octahydro- cyclopenta[c]pyrrol-5- ylamino]-acetyl}- pyrrolidine-2-carbonitrile hydrochloride
5
cis-1-[2-(2-Acetyl- octahydro-cyclopenta[c] pyrrol-5-ylamino)- acetyl]-pyrrolidine-2- carbonitrile hydro- chloride
6
cis-5-[2-(2-Cyano- pyrrolidin-1-yl)-2-oxo- ethylamino]-hexahydro- cyclopenta[c] pyrrole-2-carboxylic acid isopropylamide hydrochloride
7
cis-1-{2-[2-(Morpholine- 4-carbonyl)-octahydro- cyclopenta[c]pyrrol-5- ylamino]-acetyl}- pyrrolidine-2-carbonitrile hydrochloride
8
cis-1-{2-[2-(Pyrrolidine- 1-carbonyl)-octahydro- cyclopenta[c]pyrrol-5- ylamino]-acetyl}- pyrrolidine-2-carbonitrile hydrochloride
9
cis-5-[2-(2-Cyano- pyrrolidin-1-yl)-2-oxo- ethylamino]-hexahydro- cyclopenta[c]pyrrole-2- carboxylic acid dimethylamide triflutate
10
trans-5-[2-(2-Cyano- pyrrolidin-1-yl)-2-oxo- ethylamino]-hexahydro- cyclopenta[c]pyrrole-2- carboxylic acid dimethylamide triflutate
Further, this invention relates to compounds of the following formula (I-1c) as intermediates in the synthesis of compounds having formula (I):
wherein:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocycle alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
Furthermore, this invention relates to the preparation process of compounds of formula (IB), wherein the preparation process comprises the following steps of:
reacting starting material 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid tert-butyl ester (I-1a) with trifluoroacetic acid in the solvent of dichloromethane in an ice-water bath to obtain hexahydro-cyclopenta[c]pyrrol-5-one triflutate (I-1b);
reacting hexahydro-cyclopenta[c]pyrrol-5-one triflutate (I-1b) with acyl chloride or ester, in the presence of base to give the compounds of formula (I-1c);
reacting the said compounds of formula (I-1c) with equivalent amounts of different amines, sodium triacetoxyborohydride and triethylamine in the solvent of methanol at room temperature to obtain the compounds of formula (IB);
wherein:
R is selected from the group consisting of alkyl, cycloalkyl, haloalkyl, aryl, heteroaryl, aminocarbonyl alkyl, amide alkyl, aminocarbonyl alkyl having heterocycle and aminoalkyl, wherein the heterocycle is 5- or 6-membered hetero ring further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, alkylamino, amide group, aminocarbonyl, cyano, alkynyl, alkoxyl, aryloxyl, aminoalkyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen;
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
Preferably, in the preparation process described above, R is the following formula:
wherein:
R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester;
R 6 and R 7 are each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen; and
W is C, S or O atom.
Furthermore, this invention relates to a pharmaceutical composition comprising compounds or salts thereof having formula (I) in an effective therapeutic dose, as well as pharmaceutically acceptable carrier.
Furthermore, this invention relates to a use of the compounds or pharmaceutical acceptable salts having formula (I) in the preparation of a medicament as a dipeptidyl peptidase (DPPIV) inhibitor.
In other words, this invention is intended to provide the new aza-bicyclo alkane derivatives of formula (ID) and (IE) and tautomers, enantiomers, non-enantiomers, racemes, and pharmaceutically acceptable salts, and metabolites and metabolic precursors or prodrugs thereof.
wherein:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
n is an integer from 0 to 4;
R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester; and
R 7 is each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen.
Preferably, this invention relates to compounds or pharmaceutically acceptable salts of formula (IF) and (IG):
wherein:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
R 5 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, alkylamino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, carboxylic acid and carboxylic ester; and
R 7 is each independently selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkynyl, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester and halogen.
Furthermore, this invention also relates to compounds of the following formula (I-1c) or (I-1g) as intermediates in the synthesis of compounds having formula (I):
wherein:
R 1 is selected from the group consisting of hydrogen, alkyl, cycloalkyl, heterocyclo alkyl, aryl, heteroaryl, —C(O)NR 3 R 4 , —C(O)R 3 and —C(O)OR 3 , wherein the alkyl, cycloalkyl, heterocyclo alkyl, aryl or heteroaryl is further substituted with one or more groups selected from the group consisting of alkyl, aryl, hydroxyl, amino, alkoxyl, aryloxyl and heterocyclo alkyl;
R 3 and R 4 are each independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, heteroaryl and heterocyclo alkyl, wherein the alkyl, cycloalkyl, aryl, heteroaryl or heterocyclo alkyl is further substituted with one or more groups selected from the group consisting of alkyl, cycloalkyl, aryl, heteroaryl, alkoxyl, cycloalkoxyl, aryloxyl, heteroaryloxyl, halogen, hydroxyl, amino, cyano, hydroxyalkyl, heterocyclo alkyl, heterocyclo alkoxyl, trifluoromethyl, carboxylic acid and carboxylic ester; and
R 3 and R 4 are attached together with the N atom to form a 3 to 8 membered hetero ring, wherein the 3 to 8 membered hetero ring further contains one or more heteroatoms selected from the group consisting of N, O and S atom, and the 3 to 8 membered rings are further substituted with one or more groups selected from the group consisting of alkyl, aryl, heteroaryl, haloalkyl, haloalkoxyl, hydroxyl, amino, cyano, alkoxyl, aryloxyl, hydroxyalkyl, heterocyclo alkyl, carboxylic acid, carboxylic ester, halogen and —NR 3 R 4 ;
This invention relates to compounds having formula (I) or pharmaceutically acceptable salts, wherein the compounds having formula (I) are in pharmaceutically acceptable free-form and the forms of acid addition salts, and provides the pharmaceutically acceptable (nontoxic, physiologically acceptable) salts thereof; wherein the pharmaceutically acceptable salts are selected from the group consisting of hydrochloride, p-toluenesulfonate, tartarate, maleate, lactate, methanesulfonate, sulfate, phosphate, citrate, acetate and triflutate. Preferably, the salts are p-toluenesulfonate, hydrochloride and trifluoroacetate. More preferably, the salts are hydrochloride and triflutate.
DETAILED DESCRIPTION OF THE INVENTION
Unless otherwise stated, the following terms used in the specification and claims have the meanings discussed below.
“Alkyl” refers to a saturated aliphatic hydrocarbon group including C 1 -C 20 straight chain and branched chain groups. Preferably an alkyl group is a middle size alkyl having 1 to 10 carbon atoms, e.g., methyl, ethyl, propyl, 2-propyl, n-butyl, iso-butyl, tert-butyl, pentyl, and the like. More preferably, it is a lower alkyl having 1 to 4 carbon atoms, e.g., methyl, ethyl, propyl, 2-propyl, n-butyl, iso-butyl, or tert-butyl, and the like. The alkyl group may be substituted or unsubstituted. When substituted, the substituent group(s) is preferably independently halo, hydroxyl, lower alkoxy, aryl, aryloxy, heteroaryl, heterocyclo alkyl, C(O)R 3 and C(O)NR 3 R 4 .
“Cycloalkyl” refers to a 3 to 8 membered all-carbon monocyclic ring, an all-carbon 5-membered/6-membered or 6-membered/6-membered fused bicyclic ring or a multicyclic fused ring (a “fused” ring system means that each ring in the system shares an adjacent pair of carbon atoms with other ring in the system) group wherein one or more rings may contain one or more double bonds, but none of the rings has a completely conjugated pi-electron system. Examples of cycloalkyl groups are cyclopropane, cyclobutane, cyclopentane, cyclopentene, cyclohexane, cyclohexadiene, adamantane, cycloheptane, cycloheptatriene, and the like. The cycloalkyl group may be substituted or unsubstituted. When substituted, the substituent group(s) is preferably one or more independently selected from the group consisting of lower alkyl, trihaloalkyl, halo, hydroxy, lower alkoxy, aryl (optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), aryloxy (optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), 6-membered heteroaryl (having 1 to 3 nitrogen atoms on the ring, the carbons on the ring being optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), 5-membered heteroaryl (having 1 to 3 heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, the carbon and nitrogen atoms of the group being optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), 5- or 6-membered hetercyclo alkyl (having 1 to 3 heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, the carbon and nitrogen (if present) atoms of the group being optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), mercapto, (lower alkyl) thio, arylthio (optionally substituted with one or more groups which each independently is halo, hydroxy, lower alkyl or lower alkoxy groups), cyano, acyl, thioacyl, O-carbamyl, N-carbamyl, O-thiocarbamyl, N-thiocarbamyl, C-amido, N-amido, nitro, N-sulfonamido, S-sulfonamido, C(O)R 3 , C(O)NR 3 R 4 and —C(O)OR 3 .
“Alkenyl” refers to an alkyl group as defined above having at least 2 carbon atoms and at least one carbon-carbon double bond. Representative examples include, but are not limited to ethenyl, 1-propenyl, 2-propenyl, 1-, 2-, 3-butenyl, and the like.
“Alkynyl” refers to an alkyl group as defined above having at least 2 carbon atoms and at least one carbon-carbon triple bond. Representative examples include, but are not limited to ethynyl, 1-propynyl, 2-propynyl, 1-, 2-, 3-butynyl, and the like.
“Aryl” refers to groups having at least one aromatic ring, i.e., having a conjugated pi-electron system, including all-carbon cyclic aryl, heteroaryl and biaryl group. Said aryl group may be optionally substituted with one or more groups each independently selected from the group consisting of halo, trihalomethyl, hydroxy, SR, nitro, cyano, alkoxyl and alkyl.
“Heteroaryl” refers to an aryl having 1 to 3 heteroatoms selected from the group consisting of N, O, and S as ring atoms, the remaining ring atoms being C. Said ring is 5- or 6-membered ring. The examples of heteroaryl groups include furyl, thienyl, pyridyl, pyrrolyl, N-alkyl pyrrolyl, pyrimidinyl, pyrazinyl, imidazolyl, and the like.
“Heterocyclo alkyl” refers to a monocyclic or fused ring group of 5 to 9 ring atoms, wherein one, or two ring heteroatoms are selected from the group consisting of N, O, and S(O)n (n is integer from 0 to 2), the remaining ring atoms are C, in addition, the ring may also have one or more double bonds, but not have a completely conjugated pi-electron system. The unsubstituted heterocyclo alkyl includes, but is not limited to pyrrolidyl, piperidine subbase, piperazine subbase, morpholinyl, thiomorpholinyl, homopiperazinyl, and the like. The heterocyclo alkyl may be substituted or unsubstituted. When substituted, the substituent is preferably one or more, more preferably one, two, or three, further more preferably one or two groups, each independently selected from the group consisting of lower alkyl, trihaloalkyl, halo, hydroxy, lower alkoxy, cyano and acyl. Preferably, the heterocyclo alkyl is optionally substituted with one or two groups independently selected from the group consisting of halo, lower alkyl, trihaloalkyl, hydroxy, mercapto, cyano, N-amido, and carboxy.
“Hydroxy” refers to an —OH group.
“Alkoxyl” refers to both an —O-(alkyl) and an —O-(unsubstituted cycloalkyl) group. Representative examples include, but are not limited to, e.g., methoxy, ethoxy, propoxy, butoxy, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, and the like.
“Haloalkoxy” refers to an —O-(haloalkyl). Representative examples include, but are not limited to, e.g., trifluoromethoxy, tribromomethoxy, and the like.
“Aryloxyl” refers to both an —O-aryl and an —O-heteroaryl group, wherein the aryl and heteroaryl are as defined above. Representative examples include, but are not limited to, e.g., phenoxy, pyridinyloxy, furanyloxy, thienyloxy, pyrimidinyloxy, pyrazinyloxy, and the like, and derivatives thereof.
“Mercapto” refers to a —SH group.
“Alkylthio” refers to a —S-(alkyl) and a —S-(unsubstituted cycloalkyl) group. Representative examples include, but are not limited to, e.g., methylthio, ethylthio, propylthio, butylthio, cyclopropylthio, cyclobutylthio, cyclopentylthio, cyclohexylthio, and the like.
“Arylthio” refers to a —S-aryl and a —S-heteroaryl group, wherein the aryl and heteroaryl are as defined above. Representative examples include, but are not limited to, e.g., phenylthio, pyridinylthio, furanylthio, thienylthio, pyrimidinylthio, and the like, and derivatives thereof.
“Acyl” refers to a —C(O)—R″ group, where R″ is selected from the group consisting of hydrogen, lower alkyl, trihalomethyl, unsubstituted cycloalkyl, aryl (optionally substituted with one or more, preferably one, two, or three substituents selected from the group consisting of lower alkyl, trihalomethyl, lower alkoxy and halo groups), heteroaryl (bonded through a ring carbon) (optionally substituted with one or more, preferably one, two, or three substitutents selected from the group consisting of lower alkyl, trihaloalkyl, lower alkoxy and halo groups), and heteroalicyclic (bonded through a ring carbon) (optionally substituted with one or more, preferably one, two, or three substituents selected from the group consisting of lower alkyl, trihaloalkyl, lower alkoxy and halo groups). Representative acyl groups include, but are not limited to, acetyl, trifluoroacetyl, benzoyl, and the like.
“Thioacyl” refers to a —C(S)—R″ group, wherein R″ is as defined above.
“Acetyl” refers to a —C(O)CH 3 group.
“Halo” refers to fluoro, chloro, bromo, or iodo, preferably fluoro or chloro.
“Trifluoromethyl” refers to a —CF 3 group.
“Cyano” refers to a —C≡N group.
“Amino” refers to a —NH 2 group.
“Carboxylic acid” refers to a —COOH group.
“Carboxylic ester” refers to a —COOR group, wherein R is alkyl or cycloalkyl.
“Hydroxyl alkyl” refers to a —(CH 2 )rNH 2 group, wherein r is an integer from 1 to 4.
“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event or circumstance may or may not occur. For example, “heterocycle group optionally substituted with an alkyl group” means that the alkyl may or may not be present, and the description includes situations where the heterocycle group is substituted with an alkyl group and situations where the heterocyclo group is not substituted with the alkyl group.
A “pharmaceutical composition” refers to a mixture of one or more of the compounds described herein, or physiologically/pharmaceutically acceptable salts or prodrugs thereof, with other chemical components, such as physiologically/pharmaceutically acceptable carriers and excipients. The purpose of a pharmaceutical composition is to facilitate administration of a compound to an organism.
Synthesis Method of the Invention Compound
In order to complete the objective of the invention, the invention applies the following technical solution:
A preparation process of compounds of formula (IB) or pharmaceutically acceptable salts of the invention, comprising the following steps of:
Reacting starting material 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid tert-butyl ester (I-1a) with trifluoroacetic acid in the solvent of dichloromethane in an ice-water bath to obtain hexahydro-cyclopenta[c]pyrrol-5-one triflutate (I-1b); reacting hexahydro-cyclopenta[c]pyrrol-5-one triflutate (I-1b) with acyl chloride or ester in the presence of base to give the compounds of formula (I-1c); reacting the compounds of formula (I-1c) with equivalent amounts of different amines, sodium triacetoxyborohydride and triethylamine in the solvent of methanol at room temperature to obtain the compounds of formula (IB).
This invention relates to a pharmaceutical composition comprising a compound or salt having formula (I) in an effective therapeutic dose, as well as a pharmaceutically acceptable carrier, or this invention relates to a use of the compounds or salts in the preparation of a medicament as a dipeptidyl peptidase inhibitor. In other words, this invention also provides the composition comprising the above compound in an effective therapeutic dose, and the use of the compounds in the preparation of a medicament as a dipeptidyl peptidase inhibitor.
Specific Implemention Methods
The following examples serve to illustrate the invention, but the examples should not be considered as limiting the scope of the invention.
EXAMPLES
The compound's structure determination was confirmed by NMR and MS. NMR chemical shifts were given in ppm (10 −6 ). NMR was determined by a Bruker AVANCE-400 machine. The solvent were deuterated-chloroform (CDCl 3 ) and deuterated-dimethyl sulfoxide (DMSO-d6) with tetramethylsilane (TMS) as internal standard. Chemical shifts were given in ppm (10 −6 ).
MS was determined by a FINNIGAN LCQ Ad (ESI) mass spectrometer.
The average of inhibitory rate of kinase and IC 50 was determined by a NovoStar ELIASA (BMG Co. German).
Thin-layer silica gel was yantai huanghai HSGF254 or qingdao GF254 silica gel plate.
Column chromatography generally used yantai huanghai 200-300 mesh silica gel as carrier.
DMSO-D 6 : deuterated-dimethyl sulfoxide.
CDCl 3 : deuterated-chloroform.
Example 1
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide hydrochloride
Preparation of [2-(2-carbamoyl-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1b
N-tert-butyloxycarbonyl glycine 1a (5 g, 28.56 mmol) and L-prolinamide (3.25 g, 28.50 mmol) were dissolved in 75 mL of N,N-dimethylformamide, the resulting solution was cooled down to 0° C. (centigrade), and 1-hydroxybenzotriazole (11.8 g, 87.3 mmol), N-ethyl-N′-(dimethylaminopropyl)-carbodiimide (11.3 g, 59 mmol) and triethylamine (12.1 mL, 87.3 mmol) were then added with stirring. Upon completion of the addition, the reaction mixture was allowed to increase to room temperature, and stirred overnight. After thin lay chromatography showed the starting material disappeared, N,N-dimethylformamide was evaporated below 50° C., and the reaction solution was extracted with ethyl acetate (200 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by recrystallization with ethyl acetate to obtain the title compound [2-(2-carbamoyl-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1b (7.42 g, yield 95.8%) as a white powder.
MS m/z (ESI): 272.1(M+1)
Preparation of [2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1c
In a dry three-neck flask under a nitrogen atmosphere, 286 mL of pyridine, [2-(2-carbamoyl-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1b (13.5 g, 49.8 mmol) and imidazole (7.11 g, 104.6 mmol) were added successively. The reaction system was cooled down to −35° C., and phosphorus oxychloride (19 mL, 204.2 mmol) was then added dropwise to the solution with stirring. After stirring for 1 hour at −35° C., the reaction mixture was allowed to increase to room temperature, and stirred for another 0.5 hour. Pyridine was evaporated under low temperature, and the reaction mixture was diluted with water, then extracted with ethyl acetate (200 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound [2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1e (10.7 g, yield 84.9%) as a white powder.
MS m/z (ESI): 254.3(M+1)
Preparation of 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d
[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethyl]-carbamic acid tert-butyl ester 1e (13.7 g, 54.2 mmol) was dissolved in the solvent mixture of 140 mL of ether and 40 mL of water, and 37% hydrochloride acid (90 mL) were then added dropwise to the solution. Upon completion of the addition, the reaction mixture was stirred for 1 hour in an ice-water bath, the solvent was evaporated, and ether was added to the residue to centrifuge to give 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (10 g, yield 98%) as a white powder.
MS m/z (ESI): 154.4(M+1)
Preparation of hexahydro-cyclopenta[c]pyrrole-5-one triflutate 1f
5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid tert-butyl ester 1e (0.32 g, 1.42 mmol) was dissolved in 10 mL of dichloromethane, and trifluoroacetic acid (3.27 mL, 42.7 mmol) was then added to the solution in an ice-water bath. Upon completion of the addition, the reaction mixture was stirred at 0° C. for 30 minutes, then the solvent was evaporated to dryness to obtain the title compound hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f which was directly used in the further reaction.
MS m/z (ES!): 126.4(M+1)
Preparation of 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1g
The crude product of hexahydro-cyclopenta[c]pyrrole-5-one triflutate 1f obtained above was dissolved in 15 mL of acetonitrile, and potassium carbonate (0.24 g, 1.71 mmol) was then added to the solution in an ice-water bath, followed by N,N-dimethylcarbamic chloride (0.14 mL, 1.56 mmol). Upon completion of the addition, the reaction mixture was allowed to increase to room temperature, and stirred for 2 hours, the solvent was evaporated, and 50 mL of water was then added to the residue. The mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1g (0.19 g, yield 68.3%) as a light yellow oil.
MS m/z (ESI): 197.4(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1h
1-(2-Amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.36 g, 1.91 mmol) was dissolved in 20 mL of methanol, and 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1g (0.25 g, 1.28 mmol) and sodium triacetoxyborohydride (1.22 g, 5.74 mmol) were then added to the solution with stirring. After stirring for 3 hours at room temperature, the resulting mixture was concentrated, and 20 mL of saturated sodium carbonate solution was then added to the mixture. The reaction mixture was extracted with dichloromethane (20 mL×10). The combined organic extracts were washed with 10 mL of saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to give the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1h (0.3 mg, yield 53%) as a white powder.
MS m/z (ESI): 334.5(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide hydrochloride 1
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1h (200 mg, 0.687 mmol) was dissolved in 10 mL of dichloromethane, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The solvent was evaporated to dryness, and 10 mL of ether was then added to the residue. The resulting precipitate was centrifuged to give the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide hydrochloride 1 (180 mg, yield 80%) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.82(dd, 1H, J 1 =4 Hz, J 2 =5.2 Hz), 4.02 (dd, 2H, J 1 =J 2 =16.4 Hz), 3.62-3.25(m, 7H), 2.76(s, 6H), 2.51-1.49(m, 10H).
Example 2
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester hydrochloride
Preparation of 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (0.559 g, 2.34 mmol) was dissolved in 20 mL of acetonitrile, and potassium carbonate (0.646 g, 4.68 mmol) and methyl chloroformate (0.22 mL, 2.8 mmol) were then added to the solution in an ice-water bath successively. Upon completion of the addition, the reaction mixture was allowed to increase to room temperature, and stilled overnight. The solvent was evaporated, and 50 mL of water was then added to the residue. The mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2a (0.25 g, yield 58.4%) as a colorless oil.
MS m/z (ESI): 184(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2b
1-(2-Amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.43 g, 2.29 mmol) was dissolved in 20 mL of methanol, and 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2a (0.28 g, 1.53 mmol) and sodium triacetoxyborohydride (1.46 g, 6.88 mmol) were then added to the solution with stirring. After stirring for 3 hours at room temperature, the reaction mixture was concentrated, then saturated sodium carbonate solution (20 mL) was added to the mixture. The reaction mixture was extracted with dichloromethane (20 mL×3). The combined organic extracts were washed with 10 mL of saturated brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2b (0.22 g, yield 41%) as a white powder.
MS m/z (ESI): 357(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester hydrochloride 2
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester 2b (200 mg, 0.687 mmol) was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid methyl ester hydrochloride 2 (200 mg) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.71(m, 1H), 3.93(m, 2H), 3.59-3.28(m, 10H), 2.64(m, 2H), 2.34(m, 2H), 2.17(m, 2H), 2.08(m, 2H).
Example 3
cis-1-{2-[2-(2-Hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride
Preparation of 2-(2-hydroxy-acetyl)-hexahydro-cyclopenta[c]pyrrol-5-one 3a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (764.8 mg, 3.2 mmol) and 2-hydroxyacetic acid (267.5 mg, 3.52 mmol) were dissolved in 10 mL of acetonitrile, and hydroxyacetic acid (1.3 g, 9.6 mmol), 1-ethyl-3-dimethylaminopropyl-carbodiimide hydrochloride (1.23 g, 6.4 mmol) and triethylamine (1.3 mL, 9.6 mmol) were then added to the solution in an ice-water bath. The ice-water bath was then removed, and the reaction mixture was stirred overnight at 25° C. The solvent was evaporated, and 20 mL of ethyl acetate was then added to the residue. The mixture was filtered and the filtrate was washed with 20 mL of water. The combined organic extracts were dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 2-(2-hydroxy-acetyl)-hexahydro-cyclopenta[c]pyrrol-5-one 3a (0.375 g, yield 64%) as a colorless oil.
MS m/z (ESI): 184(M+1)
Preparation of cis-1-{2-[2-(2-hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 3b
2-(2-Hydroxy-acetyl)-hexahydro-cyclopenta[c]pyrrol-5-one 3a (0.375 g, 2.05 mmol) and 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.78 g, 4.1 mmol) were dissolved in the solvent mixture of 5 mL of methanol and 10 mL of sodium triacetoxyborohydride (0.87 g, 4.1 mmol) was then added to the mixture, and the mixture was stirred overnight at room temperature. The resulting mixture was concentrated under reduced pressure, and methanol (50 mL) and potassium carbonate (2 g, 7 mmol) were then added to the mixture. After 0.5 hour's stirring, the mixture was filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to give the title compound cis-1-{2-[2-(2-hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 3b which was directly used in the further reaction.
MS m/z (ESI): 357(M+1)
Preparation of cis-1-{2-[2-(2-hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 3
cis-1-{2-[2-(2-Hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 3b was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-1-{2-[2-(2-hydroxy-acetyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 3 (100 mg) as a white powder.
Example 4
cis-1-{2-[2-(Piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride
Preparation of 2-(piperidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 4a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (478 mg, 2 mmol) was dissolved in 20 mL of dichloromethane, and 1-methyl-3-(piperidine-1-carbonyl)-1H-imidazol-3-ium iodide (0.96 g, 3 mmol) and triehtylamine (0.84 mL, 6 mmol) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred overnight at room temperature, 20 mL of water was then added to the mixture to quech the reaction, and the mixture was extracted with dichloromethane (50 mL×3). The combined organic extracts were washed with 10% citric acid solution (50 mL) and 50 mL of saturated brine successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 2-(piperidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 4a (0.41 g, yield 87%) as a colorless oil.
MS m/z (ESI): 237(M+1)
Preparation of cis-1-{2-[2-(piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 4b
2-(Piperidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 4a (0.41 g, 1.74 mmol) and 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.5 g, 2.6 mmol) were dissolved in 50 mL of tetrahydrofuran, and sodium sulfate (5 g) and acetic acid (0.05 mL) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred for 0.5 hour at room temperature, sodium triacetoxyborohydride (1.1 g, 5.2 mmol) was then added to the mixture, and the mixture was stirred for 3 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and saturated sodium carbonate solution (50 mL) was then added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-1-{2-[2-(piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 4b which was directly used in the further reaction.
MS m/z (ESI): 410(M+1)
Preparation of cis-1-{2-[2-(piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 4
cis-1-{2-[2-(Piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 4b was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-1-{2-[2-(piperidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 4 (0.16 g) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.83(dd, 1H, J 1 =3.0 Hz, J 2 =5.8 Hz), 4.09 (dd, 2H, J 1 =J 2 =13.1 Hz), 3.70-3.30(m, 10H), 2.72(m, 2H), 2.47(m, 2H), 2.31-2.00(m, 5H), 1.66-1.52(m, 8H).
Example 5
cis-1-[2-(2-Acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile
Preparation of 2-acetyl-hexahydro-cyclopenta[c]pyrrol-5-one 5a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (717 mg, 3 mmol) was dissolved in 20 mL of acetonitrile, and acetic anhydride (0.42 mL, 4.5 mmol) and triethylamine (0.98 mL, 9 mmol) were then added to the solution in an ice-water bath. Upon completion of the addition, the reaction mixture was then stirred overnight in an ice-water bath. The solvent was evaporated, and water (50 mL) was then added to the residue. The mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 2-acetyl-hexahydro-cyclopenta[c]pyrrol-5-one 5a (0.36 g, yield 72%) as a colorless oil.
MS m/z (ESI): 168.4(M+1)
Preparation of cis-1-[2-(2-acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile 5b
2-Acetyl-hexahydro-cyclopenta[c]pyrrol-5-one 5a (0.36 g, 2.15 mmol) and 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.614 g, 3.23 mmol) were dissolved in 50 mL of tetrahydrofuran, and sodium sulfate (5 g) and acetic acid (0.05 mL) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred for 0.5 hour at room temperature, sodium triacetoxyborohydride (1.37 g, 6.46 mmol) was then added to the mixture, and the mixture was stirred for 3 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and saturated sodium carbonate solution (50 mL) was then added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-1-[2-(2-acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile 5b which was directly used in the further reaction.
MS m/z (ESI): 305.5(M+1)
Preparation of cis-1-[2-(2-acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile hydrochloride 5
The resulting cis-1-[2-(2-Acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile 5b was dispersed in 20 mL of ether, and a solution of 0.5 N hydrochloride acid in 4 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-1-[2-(2-acetyl-octahydro-cyclopenta[c]pyrrol-5-ylamino)-acetyl]-pyrrolidine-2-carbonitrile hydrochloride 5 (0.23 g) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.71(m, 1H), 3.92(m, 2H), 3.69-3.37(m, 7H), 2.69(m, 2H), 2.33(m, 2H), 2.13(m, 2H), 2.04-2.00(m, 5H), 1.48(m, 2H).
Example 6
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide hydrochloride
Preparation of 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (717 mg, 3 mmol) was dissolved in 20 mL of dichloromethane, and 2-isocyanatopropane (9 mL, 9 mmol) and triethylamine(1.7 mL, 12 mmol) were then added to the solution in an ice-water bath. Upon completion of the addition, the reaction mixture was stirred overnight at room temperature, water (50 mL) was then added to the mixture. The mixture was extracted with dichloromethane (50 mL×3). The combined organic extracts were washed with 10% citric acid solution (50 mL) and 50 mL of saturated brine successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6a (0.3 g, yield 47.6%) as a colorless oil.
MS m/z (ESI): 211(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6b
5-Oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6a (0.3 g, 1.43 mmol) and (s)-1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.407 g, 2.14 mmol) were dissolved in 50 mL of tetrahydrofuran, and sodium sulfate (5 g) and acetic acid (0.05 mL) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred for 0.5 hour at room temperature, sodium triacetoxyborohydride (0.9 g, 4.3 mmol) was then added to the mixture, and the mixture was stirred for 3 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and saturated sodium carbonate solution (50 mL) was then added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6b which was directly used in the further reaction.
MS m/z (ESI): 384(M+1)
Preparation of cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide hydrochloride 6
The resulting cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide 6b was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid isopropylamide hydrochloride 6 (80 mg) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.70(m, 1H), 3.92(m, 2H), 3.76-3.32(m, 8H), 2.63-1.41(m, 10H), 1.01(d, 6H, J=6 Hz).
Example 7
cis-1-{2-[2-(Morpholine-4-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride
Preparation of 2-(morpholine-4-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 7a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (574 mg, 2.4 mmol) was dissolved in 20 mL of acetonitrile with stirring, and potassium carbonate (0.397 g, 2.88 mmol) was then added to the solution in an ice-water bath, followed by morpholine-4-carbonyl chloride (0.323 mL, 2.64 mmol). Upon completion of the addition, the reaction mixture was stirred overnight in an ice-water bath, then the solvent was evaporated, and water (50 mL) was added to the residue. The mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 2-(morpholine-4-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 7a (0.572 g, yield 77.3%) as a colorless oil.
MS m/z (ESI): 239(M+1)
Preparation of cis-1-{2-[2-(morpholine-4-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 7b
2-(Morpholine-4-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 7a (0.64 g, 2.69 mmol) and 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.764 g, 4.03 mmol) were dissolved in 50 mL of tetrahydrofuran, and sodium sulfate (5 g) and acetic acid (0.05 mL) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred for 0.5 hour at room temperature, sodium triacetoxyborohydride (1.71 g, 8.07 mmol) was then added to the mixture, and the mixture was stirred for 3 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and saturated sodium carbonate solution (50 mL) was then added to the residue. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water successively, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purify by silica gel column chromatography to obtain the title compound cis-1-{2-[2-(morpholine-4-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 7b to be used in the further reaction.
MS m/z (ESI): 376.7(M+1)
Preparation of cis-1-{2-[2-(morpholine-4-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 7
The resulting cis-1-{2-[2-(morpholine-4-carbonyl)-octahydro-cyclopenta[c]-pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 7b was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-1-{2-[2-(morpholine-4-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 7 (30 mg, yield 3%) as a white powder.
Example 8
cis-1-{2-[2-(Pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride
Preparation of 2-(pyrrolidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 8a
Hexahydro-cyclopenta[c]pyrrol-5-one triflutate 1f (478 mg, 2 mmol) was dissolved in 20 mL dichloromethane, and pyrrolidine-1-carbonyl chloride (0.276 mL, 2.5 mmol) and triethylamine (0.84 mL, 6 mmol) were then added to the solution in an ice-water bath. Upon completion of the addition, the reaction mixture was stirred overnight at room temperature, 10% citric acid solution was then added to the mixture to adjust to pH 4. The mixture was extracted with dichloromethane (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound 2-(pyrrolidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 8a (0.26 g, yield 58.5%) as a colorless oil.
MS m/z (ESI): 223(M+1)
Preparation of cis-1-{2-[2-(pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 8b
2-(Pyrrolidine-1-carbonyl)-hexahydro-cyclopenta[c]pyrrol-5-one 8a (0.26 g, 1.17 mmol) and 1-(2-amino-acetyl)-pyrrolidine-2-carbonitrile hydrochloride 1d (0.33 g, 1.75 mmol) were dissolved in 50 mL of tetrahydrofuran, and sodium sulfate (5 g) and acetic acid (0.05 mL) were then added to the solution. Upon completion of the addition, the reaction mixture was stirred for 0.5 hour at room temperature, sodium triacetoxyborohydride (0.75 g, 3.5 mmol) was then added to the mixture, and the mixture was stirred for 3 hours at room temperature. The reaction mixture was concentrated under reduced pressure, and saturated sodium carbonate solution (50 mL) was then added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine and 50 mL of water, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-1-{2-[2-(pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 8b which was directly used in the further reaction.
MS m/z (ESI): 396(M+1)
Preparation of cis-1-{2-[2-(pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 8
The resulting cis-1-{2-[2-(pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile 8b was dispersed in 10 mL of ether, and a solution of 0.5 N hydrochloride acid in 2 mL of ether was then added to the solution in an ice-water bath. The precipitate was centrifuged to obtain the title compound cis-1-{2-[2-(pyrrolidine-1-carbonyl)-octahydro-cyclopenta[c]pyrrol-5-ylamino]-acetyl}-pyrrolidine-2-carbonitrile hydrochloride 8 (90 mg) as a white powder.
1 H NMR (CD 3 OD, 400 MHz) δ 4.72(m, 1H), 4.09(m, 2H), 3.43-3.30(m, 11H), 2.62(m, 2H), 2.35(m, 2H), 2.18(m, 2H), 2.08(m, 2H), 1.77(m, 4H)
Example 9
cis-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide triflutate
The resulting cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1h (157 mg, 0.54 mmol) from example 1 was dispersed in 10 mL of dichloromethane, and trifluoroacetic acid (2 mL) was then added to the solution in an ice-water bath. The reaction mixture was stirred for 0.5 hour. The precipitate was centrifuged to obtain the title compound cis-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide triflutate 9 (201 mg) as a white powder.
1 H NMR (CDCl 3 , 400 MHz) δ 4.74(t, 1H, J=5.2 Hz), 3.98(d, 1H, J=15.6 Hz), 3.79(d, 1H, J=15.6 Hz), 3.57-3.25(m, 7H), 2.75(s, 6H), 2.55(m, 2H), 2.33(m, 2H), 2.20-2.08(m, 4H), 1.74(m, 2H)
Example 10
trans-5-[2-(2-Cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrolo-2-carboxylic acid dimethylamide triflutate
Preparation of cis-5-hydroxy-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10a
In a dry three-neck flask under a nitrogen atmosphere, 5-oxo-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 1g (1.58 g, 8.06 mmol) was dissolved in 30 mL of tetrahydrofuran, and a solution of lithium tri-tert-butoxyaluminium hydride (2.45 g, 9.6 mmol) in 30 mL of tetrahydrofuran was then added dropwise at −25° C. with stirring. Upon completion of the addition, the reaction mixture was stirred for 2.5 hours at −25° C., and water was added to quench the reaction. 20 mL of saturated ammonium chloride was added to the mixture, then the reaction mixture was allowed to increase to room temperature, and extracted with dichloromethane (50mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-5-hydroxy-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10a (1.27 g, yield 80%) as a colorless oil.
MS(m/z) (ESI): 199(M+1)
Preparation of cis-methanesulfonic acid 2-dimethylcarbamoyl-octahydro-cyclopenta[c]pyrrol-5-yl ester 10b
In a dry one-neck flask under a nitrogen atmosphere, cis-5-hydroxy-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10a (1.69 g, 8.5 mmol) was dissolved in 30 mL of dichloromethane, and triethylamine (1.66 mL, 14.45 mmol) and methanesulfonyl chloride (2.2 g, 21.74 mmol) were then added successively in an ice-water bath. The reaction mixture was stirred for 0.5 hour, and allowed to increase to room temperature, then the reaction mixture was stirred for 2 hours, concentrated under reduced pressure, and water (20 mL) was added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×6). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound cis-methanesulfonic acid 2-dimethylcarbamoyl-octahydro-cyclopenta[c]pyrrol-5-yl ester 10b (1.94 g, yield 83%) as a wliite powder.
MS(m/z)(ESI): 277(M+1)
Preparation of trans-5-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10c
In a dry one-neck flask under a nitrogen atmosphere, cis-methanesulfonic acid 2-dimethylcarbamoyl-octahydro-cyclopenta[c]pyrrol-5-yl ester 10b (1 g, 3.6 mmol) was dissolved in 20 mL of N,N-dimethylformamide, and phthalimide potassium salt (993 mg, 5.4 mmol) was then added to the solution. Upon completion of the addition, the reaction mixture was allowed to increase to 70° C., and stirred for 3 hours. The mixture was concentrate under reduced pressure, and water (20 mL) was added to the mixture. The reaction mixture was extracted with ethyl acetate (50 mL×3). The combined organic extracts were washed with 50 mL of saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound trans-5-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10c (1.06 g, yield 90%) as a white powder which was directly used in the further reaction.
MS(m/z)(ESI): 328(M+1)
Preparation of trans-5-amino-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10d
In a one-neck flask, trans-5-(1,3-dioxo-1,3-dihydro-isoindol-2-yl)-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10c (1 g, 3.06 mmol) was dissolved in 20 mL of 95% ethanol, and hydrazine (490 mg, 15.3 mmol) was then added to the solution. Upon completion of the addition, the reaction mixture was heated to reflux for 8 hours, cooled down to room temperature, filtered and the filtrate was concentrated tinder reduced pressure to obtain a white powder. Methanol (25 mL) was added, and the resulting mixture was filtered and concentrated under reduced pressure. The residue was purified by Basic alumina column chromatography to obtain trans-5-amino-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10d (290 mg, yield 48%) as a colorless oil.
MS(m/z)(ESI): 198(M+1)
Preparation of trans-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide triflutate 10
In a one-neck flask, trans-1-(2-chloro-ethyl)-pyrrolidine-2-carbonitrile (334 mg, 1.94 mmol) was added, followed by a solution of 5-amino-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10d (290 mg, 1.46 mmol) in 20 mL of dichloromethane. Upon completion of the addition, the reaction mixture was heated to reflux for 48 hours, concentrated under reduced pressure. The residue was purified by silica gel column chromatography to obtain trans-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10e. Then, trans-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide 10e was dissolved in 10 mL of dichloromethane with stirring, and trifluoroacetic acid (2 mL) was then added to the solution in an ice-water bath. The reaction mixture was stirred for 0.5 hour to obtain the title compound trans-5-[2-(2-cyano-pyrrolidin-1-yl)-2-oxo-ethylamino]-hexahydro-cyclopenta[c]pyrrole-2-carboxylic acid dimethylamide triflutate 10 (201 mg) as a white solid.
MS(m/z)(ESI): 334(M+1)
1 H EVER (CDCl 3 , 400 MHz) δ 465(m, 1H) 3.93(d, 1H, J=15.2 Hz), 3.74(d, 1H, J=15.2 Hz), 3.69-3.19(m, 7H), 2.77(s, 6H), 2.18-1.96(m, 10H).
Biological Assays
Active Inhibition DPP IV Assay
Assay Procedures
The following methods can be used to measure the activities of the compounds of the invention which inhibit the enzymatic activity of DPP-IV. The compounds of the invention are tested for their ability to inhibit the enzyme activity of purified DPP-IV. The inhibition rates or the IC 50 (concentration of test compound at which 50% of the enzyme activity is inhibited) for each compound is determined by incubating fixed amounts of enzyme mixed substrate with several different concentrations of tested compounds.
Materials and Methods:
Materials include:
a. White 96-well plates (BMG),
b. Tris Buffer, to prepare 100 ml 2 mM Tris Buffer in dH 2 O, 0.0242 g Tris was dissolved in approx. 90 ml dH 2 O and pH was adjusted with HCl and NaOH to 8.00, at least dH 2 O was added to 100 ml,
c. DPPIV enzyme (CalBiochem Catalog no. 317630), dissolved in Tris Buffer to 2 mM,
d. DPPIV-Glo™ Subtrate (Promega Catalog no. G8350), dissolved in dH 2 O to 1 mM,
e. DPPIV-Glo. Buffer (Promega Catalog no. G8350),
f. Luciferin Detection Reagent (Promega Catalog no. G8350),
g. DMSO, and
h. dH 2 O.
Protocol:
The assay was carried out in the order of the following steps of:
1. Thawing the DPPIV-Glo. Buffering and equilibrating it to room temperature prior to use;
2. Equilibrating the lyophilized Luciferin Detection Reagent to room temperature prior to use;
3. Suspending the DPPIV-Glo., adding ultrapure water to the substrate vial to mix briefly, then giving 1 mM substrate;
4. Adding the Luciferin Detection Reagent to the amber bottle, followed by DPPIV-Glo. Buffer, wherein the Luciferin Detection Reagent should be dissolved in less than one minute;
5. Dissolving a tested compound to 50 fold of the desired final concentration with DMSO;
6. Adding 2 μL tested compound with a 50 fold concentration to each tube, adding 2 μL DMSO in negative and blank controls;
7. Adding 46 μL Tris Buffer to each tube, adding 48 μL Tris Buffer in blank controls;
8. Addind 2 μL DPPIV enzyme to each tube for negative controls and tested compounds;
9. Swirling and centrifuging the tubes, then transfering the substances of the tubes to the 96-well plate;
10. Mixing Substrate and DPPIV-Gloat the rate 1:49, then swirling or inverting the substances to obtain a homogeneous solution, and standing it at room temperature for 30-60 minutes prior to use;
11. Adding 50 μL of the mixed solution of DPPIV-Glo. and substrate to each 96-well plate, and covering the plate with a sealing film;
12. Gently mixing the substances of the 96 wells using a plate shaker at 300-500 rpm for 30 seconds, then incubating them at room temperature for 30 minutes to 3 hours; and
13. Recording luminescence.
The inhibition rate can be defined as: [1−(S−B)/(N−B)]*100%
S: sample B: blank control N: negative control
IC 50 of the DPP IV of the tested compounds were showed in table 1:
TABLE 1
IC 50 assay results of examples
examples
IC 50 (DPPIV)/nM
1
9
2
24
3
14
4
69
7
50
8
39
The Selective Activity Determination of DPPIV Inhibitors
Objective:
Human DPPIV (EC 3.14.21.5; Depeptidyl peptidase IV; T cell activated antigen CD26; ADA binding protein) has the activity of dipeptide aminopeptidase. It can cut off the first two amino acids in many of the N-peptide to change or lose its biological activity. Gene knockout animal and human experiments indicate that reducing DPPIV activity effectively and specifically in vivo can improve blood insulin content and lower blood sugar levels, so as to improve the symptoms of diabetes effectively. Recent studies show that there are a number of proteins (DASH) as same as DPPIV protein in activity and structure, including DPP8, DPP9, QPP and FAP and the like. Pre-clinical studies show that inhibiting the activities of these DASH members will lead to toxicity, even death. Therefore, screening DPPIV inhibitors with high selectivity and efficient has an important value for the treatment of diabetes.
Methods:
By using the insect expression system, the recombinant proteins of DPPIV, DPP8, DPP9 and QPP had been obtained. The activities of the five enzymes were detected by fluorescence Substrate. The inhibitory effects of compounds were evaluated by the effects of different compounds on inhibiting enzyme activities. Positive reference compound was LAF237.
Results:
The IC50s of Compounds:
IC50 (nM)
IC50 (nM)
IC50 (nM)
IC50 (nM)
IC50 (nM)
Example
DPPIV
DPP8
DPP9
QPP
FAP
1
16.2 ± 5.1
17381 ± 4947
5703.6 ± 162.2
>54062.8
540.6 ± 54.0
2
98.0 ± 36.4
18241 ± 2690
5043.6 ± 560.4
>56039.7
476.3 ± 112.1
Conclusion:
The two compounds can inhibit DPPIV activity obviously, have the significant selectivity on QPP and have different degree selectivity on DPP8, DPP9 and FAP.
Preliminary Evaluation of Hypoglycemic Effects of DPPIV Inhibitors
Objective:
To observe the effects on oral glucose tolerance of the DPPIV inhibitors SHR1039 (example 1) and SHR1040 (example 2) in normal ICR mice, the hypoglycemic effects in vivo have been evaluated.
Test Animals:
Species, strains: ICR mice Source: Chinese Academy of Sciences, Shanghai Laboratory Animal Center, Qualified No.: SYXK (Shanghai) 2004-2005 Weight: 25-30 g Sex: Male animals Animal Number: 40 Rearing conditions: SPF-class animal room raising, temperature: 22-24° C., Humidity: 45-80%, illumination: 150-300Lx, day and night cycle with an interval of 12 hours.
Drugs:
Name: SHR1039 (Example 1) Lot Number: 01 Color, form: white powder Purity: 96.97% Provided by: Shanghai Hengrui Medicine Co., Ltd. Preparation Method: Compounds were weighed accurately, and then dissolved in double distilled water. The suspensions of 0.5, 0.15 and 0.05 mg/ml were prepared respectively. (Note: Although the product instruction displayed the test compounds were soluble in water, but in the experiment it was poor water-soluble, i.e., at low concentration it can be dissolved, but at the concentration of 0.5 mg/ml there are still visible particles by the naked eye. 1% CMC was tried to suspend the compounds, while it was not better than double-distilled water.) Dose: 1, 3, 10 mg/kg by gavage. The volume is 20 ml/kg. Name: SHR1040 (Example 2) Lot Number: 01 Color, form: white powder Purity: 96.62% Provided by: Shanghai Hengrui Medicine Co., Ltd. Preparation Method: Compounds were weighed accurately, and then dissolved in double distilled water and fully mixed to prepare a 1.5 mg/ml solution, and then diluted into 0.5, 0.15 and 0.05 mg/ml transparent solution respectively. Dose: 1, 3, 10 mg/kg by gavage. The volume is 20 ml/kg.
Method:
1. The Effects of Compounds on Blood Glucose in Normal ICR Mice
Normal male ICR mice were randomly grouped according to weights, 6 mice in each group. The groups included a blank control group as well as different doses of the treatment groups as follows:
Test 1:
Blank control: double-distilled water by gavage.
Group 1: SHR1039 (example 1) 1 mg/kg by gavage.
SHR1039 (example 1) 3 mg/kg by gavage. SHR1039 (example 1) 10 mg/kg by gavage.
Group 2: SHR1040 (example 2) 1 mg/kg by gavage.
SHR1040 (example 2) 3 mg/kg by gavage. SHR1040 (example 2) 10 mg/kg by gavage.
Test 2:
Blank control: double-distilled water by gavage.
Group 1: SHR1039 (example 1) 1 mg/kg by gavage.
SHR1039 (example 1) 3mg/kg by gavage. SHR1039 (example 1) 10 mg/kg by gavage.
Group 2: SHR1040 (example 2) 1 mg/kg by gavage.
SHR1040 (example 2) 3 mg/kg by gavage. SHR1040 (example 2) 10 mg/kg by gavage.
Animals in each group had been fasted for 6 hours, and then pretreated with compounds or double distilled water by gavage respectively in single administration. 30 minutes later, animals were administered 2.5 g/kg glucose by gavage. Before administration and after administration of glucose at 30, 60 and 120 minuets, blood was taken to determine serum glucose levels.
2. Serum Glucose Determination:
Serum glucose is determined by glucose kit. 250 μl working enzyme solution was taken, and then 5 μl serum was added to the solution. A blank tube (5 μl double distilled water was added) and a standard tube (5 μl glucose standard solution was added) were established simultaneously, shaking respectively, and in 37° C. water bath for 20 minutes. The blank tube was tuned with, and then calorimetric assay was determined at OD505 nm.
Serum glucose concentration (BG, mmol/l)=OD sample tube /OD standard tube ×5.55
Data Processing and Statistical Analysis:
1. Mean±SD and Student-t test were used in data statistical analysis. 2. The percentage of blood glucose decline in 30 minutes after sugar administration as well as the area under the curve (AUC) was calculated.
Results:
Test 1:
Male ICR mice were fasted for 6 hours, and then treated with double distilled water, different doses of tested compounds of example 1 and example 2 by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that blood glucose level in the control group increased significantly after 2.5 g/kg glucose had administered by gavage, and reached the peak at 30 minutes. At low, middle and high doses of the compound of example 1, blood glucose was significantly lower than control group at 30 minutes, and the percentage of blood glucose thereof had decreased by 19.16%, 22.85 and 31.85% respectively. At each dose of the compound of example 2, blood glucose was significantly lower than control group at 30 minutes after the administration of glucose (P<0.01). Compared with control group, the percentage of blood glucose thereof had decreased by 25.54%, 25.92 and 26.93%.
Test 2:
Male ICR mice were fasted for 6 hours, and then treated with double distilled water; different doses of tested compound SHR1039 (example 1) and SHR1040 (example 2) by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that blood glucose level in the control group increased significantly after 2.5 g/kg glucose had administered by gavage, and reached the peak at 30 minutes. At each dose of SHR1039, blood glucose was significantly lower than control group at 30 minutes after the administration of glucose (P<0.01), and the percentage of blood glucose thereof had decreased by 26.10%, 30.24 and 32.05% respectively. At low, middle and high doses of SHR1040, blood glucose was significantly lower than control group at 30 minutes (P<0.01), and the percentage of blood glucose thereof had decreased by 24.51%, 26.96% and 27.75%.
Conclusion:
Two experimental results of this report show that tested compounds SHR1039 (example 1), SHR1040 (example 2) have significant hypoglycemic effect on oral glucose tolerance test in normal ICR mice. Moreover, tested compound SHR1039 (example 1) shows a better dose-effect relationship, and test compound SHR1040 (example 2) has a less dose-effect relationship.
Effects of DPPIV Inhibitors on Oral Glucose Tolerance in KKAy Mice
Objective:
To observe the effects of the DPPIV inhibitors SHR1039 (example 1) and SHR1040 (example 2) on oral glucose tolerance in type II diabetes KKAy mice, a preliminary evaluation of their hypoglycemic effect in vivo has been evaluated.
Test Animals:
Species, Strains: KKAy mice Source: Shanghai Laboratory Animal Center, Chinese Academy of Sciences. Qualified No.: SYXK (Shanghai) 2004-2005 Weight: 40~55 g Sex: female: 52; male: 33 Raising Conditions: SPF grade animal room raising, temperature: 22-24° C.; Humidity: 45-80%; illumination: 150-300Lx, day and night cycle with an interval of 12 hours.
Drugs:
Name: SHR1039 (example 1) and SHR1040 (example 2) Preparation Method: Compounds were weighed accurately, then dissolved in double distilled water, and full mixed to prepare a 3 mg/ml suspension, then diluted to 1, 0.3, 0.1 mg/ml transparent solution respectively. Dose: 1, 3, 10, 30 mg/kg by gavage. The volume is 10 ml/kg.
Methods:
The effects of the Compounds on Blood Glucose in KKAy Mice
Normal KKAy mice had been fasted for 6 hours, and then were randomly grouped according to weights and fasting blood glucose, 5 mice in each group. The groups included a blank control group as well as different doses of the treatment groups as follows:
Test 1: male 0704
Blank control:
double-distilled water by gavage
SHR1039:
SHR1039 (example 1) 10 mg/kg by gavage
SHR1039 (example 1) 30 mg/kg by gavage
Test 2: female 0816
Blank control:
double-distilled water by gavage
SHR1039:
SHR1039 (example 1) 3 mg/kg by gavage
SHR1039 (example 1) 10 mg/kg by gavage
Test 3: male 0712
Blank control:
double-distilled water by gavage
SHR1040:
SHR1040 (example 2) 10 mg/kg by gavage
SHR1040 (example 2) 30 mg/kg by gavage
Test 4: female 0907
Blank control:
double-distilled water by gavage
SHR1040:
SHR1040 (example 2) 3 mg/kg by gavage
SHR1040 (example 2) 10 mg/kg by gavage
Animals in each group had been fasted for 6 hours, and then pretreated with compounds or double distilled water by gavage respectively in single administration. 30 minutes later, animals were administered 2.5 g/kg (female KKAy mice) or 1.5 g/kg (male KKAy mice) glucose by gavage. After administration of glucose at 30, 60 and 120 minuets, serum glucose levels were determined by Glucometer.
Data Processing and Statistical Analysis:
3. Mean±SD and Student-t test or Anova were used in data statistical analysis.
4. The percentage of blood glucose decline in 30 minutes after sugar administration as well as the area under the curve (AUC) was calculated.
Results:
1. Compound SHR1039 (example 1): Test 1, 2
Male KKAy mice were fasted for 6 hours, and then treated with double distilled water and different doses of tested compound SHR1039 (example 1) by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that the blood glucose level in the control group increased significantly after 1.5 g/kg glucose had administered by gavage, and reached the peak at 30 minutes. In the doses of 10 mg/kg and 30 mg/kg of SHR1039 (example 1) groups, blood glucose levels thereof were both lower than control group at 30 minutes after the administration of glucose. Compared with control group, the percentage of blood glucose thereof had decreased by 16.22% and 17.15% respectively.
Female KKAy mice were fasted for 6 hours, and then treated with double distilled water and different doses of tested compound SHR1039 (example 1) by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that the blood glucose level in the control group increased significantly after 2.5 g/kg glucose had administered by gavage, and reached the peak at 30 minutes. In the doses of 3 mg/kg and 10 mg/kg of SHR1039 (example 1) groups, blood glucose levels thereof were both significantly lower than control group at 30 minutes after the administration of glucose. The percentage of blood glucose thereof had decreased by 40.63% and 24.68% respectively.
2. Compounds SHR1040 (example 2): Test 3, 4
Male KKAy mice were fasted for 6 hours, and then treated with double distilled water and different doses of tested compound SHR1040 (example 2) by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that the blood glucose level in the control group increased significantly after 1.5 g/kg glucose had administered by gavage, and reached the peak at 30 minutes. In the doses of 10 mg/kg and 30 mg/kg of SHR1040 (example 2) groups, blood glucose levels thereof were both lower than control group at 30 minutes after the administration of glucose. Compared with control group, the percentage of blood glucose thereof had decreased by 13.79% and 12.23% respectively.
Female KKAy mice were fasted for 6 hours, and then treated with double distilled water and different doses of tested compound SHR1040 (example 2) by gavage. 30 minutes after administration, the oral glucose tolerance test was made. The results showed that the blood glucose level in the control group increased significantly after 2.5 g/kg glucose had administrated by gavage, and reached the peak at 30 minutes. In the dose of 10 mg/kg of SHR1040 (example 2) group, blood glucoses were lower than control group at 30 minutes after the administration of glucose (P=0.075, anova). The percentage of blood glucose thereof had decreased by 21.55%. However, since there is a great individual difference in the mice, the results had no significant difference.
Conclusion:
Tested compounds SHR1039 (example 1) and SHR1040 (example 2) both have some hypoglycemic effects on oral glucose tolerance test in type II diabetes KKAy mice.
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Derivatives of azabicyclo octane presented by formula (I), the method of making them, and the compositions containing the same and the uses thereof as inhibitors of dipeptidyl peptidase IV (DPP-IV), wherein the substitutes in formula (I) have the same meanings as what is mentioned in the descriptions.
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[0001] This U.S. Non-Provisional patent application is Continuation of and claims the benefit of priority to U.S. patent application Ser. No. 13/961,673, filed Aug. 7, 2013, which claims the benefit of priority from U.S. Provisional Patent Application Ser. No. 61/680,635, filed Aug. 7, 2012, and U.S. Provisional Patent Application Ser. No. 61/752,230, filed Jan. 14, 2013, the entire disclosures of which are hereby incorporated by reference in their entireties.
FIELD
[0002] The present disclosure is directed to floor cleaning tools having a mechanically operated pump. Tools of the present invention are capable of performing floor or surface cleaning functions, including dispensing and recovering liquid from the floor or surface.
BACKGROUND
[0003] Conventional tools for cleaning floors range from a mop and bucket to pressure washers to automatic scrubbers. With the mop and bucket, solution is added to the bucket and then a mop made out of absorbent material is used to suck up the solution and then apply it to the floor. The mop is then used as the abrasive tool to break dirt loose from the floor. The dirt from the floor collects in the mop which is then submersed in the solution in the bucket. Dirt is rinsed from the mop by repeated dunking and wringing (usually with a mop wringer).
[0004] This process is sub-optimal for a number of reasons. First, dirt from the floor is returned to the bucket causing the solution to become dirtier and dirtier such that an area cleaned towards the end of the process is never as clean as the first area cleaned. Some mop buckets exist today that have a solution tank and a rinse tank which helps to keep the solution clean for a longer period of time, but dirt is still carried into the solution tank by the mop.
[0005] Secondly, absorbent mops required to lift solution out of the bucket and onto the floor do not make very good scrubbers. Ideally, an abrasive pad or bristle brush is used to break dirt free, but they do not absorb water and cannot be used to get the water from the bucket to the floor or dirty water from the floor back to the bucket. Sponge and abrasive pad combinations that accomplish both tasks are common for cleaning in a domestic setting, but are rarely used in commercial environments since floor coverage is too great and capacity to hold dirt is insufficient.
[0006] Pressure washers utilizing high-pressure pumps rely on the high-pressure discharge of cleaning solution as a means to break dirt free. Pressure washers are available with vacuum capability to recover the solution and the dirt as it is sprayed. These systems use a significant amount of water and are expensive and more difficult to use and maintain than the floor cleaning tool of the present invention.
[0007] With automatic scrubbers, solution is dispensed to the floor, scrub pads or brushes driven by motors break the dirt free, and a vacuum and squeegee return the dirty solution to a separate tank leaving the solution clean from start to finish. However, like pressure washers, automatic scrubbers are significantly more expensive and more difficult to operate and maintain. Additionally, automatic scrubbers are hard to maneuver in tight places and are incapable of cleaning under low profile objects (shelves, tables, chairs, etc.). Some automatic scrubbers have wand accessories with or without powered brushes for reaching in these tight spots, but these generally suffer from sub-optimal performance as automatic scrubbers are designed to clean large, unobstructed areas.
[0008] Both pressure washers and automatic scrubbers typically include electrically powered pumps or vacuums for dispensing water and/or cleaning solution and for collecting dirty water and/or cleaning solution. Such electrically operated pumps and vacuums increase the cost of these machines. Further, these machines require an electrical power source, which increases the machines' operating cost while limiting the machines' field of use (i.e. near a electrical outlet) or duration of use (i.e. until the battery is fully discharged).
SUMMARY
[0009] The present invention is a vast improvement over the mop and bucket, yet is much less expensive than the pressure washer and automatic scrubber. It is also easier to use and maintain. Embodiments of the present disclosure comprise: (1) a solution tank and a gravity-fed dispensing system to apply a solution to a surface, (2) a deck assembly having an abrasive pad or brush for scrubbing the surface being cleaned and a squeegee for collecting used cleaning solution, and (3) a mechanically operated pump that produces suction in a fluid communication path that terminates near the squeegee to convey the dirty solution into a recovery tank. Because neither the dispensing system nor the pump requires electrical power, devices of the present disclosure are simple, highly portable, cost effective, and easy to use and maintain. Additional features include dispensation of solution, keeping clean and dirty solutions separate, and collecting the dirty solution. Variations on these and other aspects of the present disclosure are described below.
[0010] In one embodiment, a portable, human-powered floor cleaning device is provided, the device comprising a chassis comprising: a clean fluid storage tank and a spent fluid collection tank; a plurality of wheels for supporting and moving the device; a deck assembly comprising a fluid pick-up orifice and a squeegee; a mechanically-driven pump housed within the chassis having an inlet and an outlet, the pump operably interconnected to a drive wheel such that a rotational movement of the drive wheel results in actuation of the pump; the fluid pick-up orifice being interconnected to the pump by a conduit for transmitting fluid from the fluid pick-up orifice to the pump; wherein conduit comprises at least one valve for substantially preventing flow of a fluid in a first direction; wherein the device is devoid of power generation unit, such that translation of the device and actuation of the pump are driven by a user imparting force to the device.
[0011] In one embodiments, a motorless floor washing machine is provided, the machine comprising: a chassis comprising a clean fluid storage tank and a spent fluid collection tank; at least two wheels for supporting and moving the machine; a trailing deck assembly comprising a fluid pick-up orifice and a squeegee; a mechanically-driven pump housed within the chassis having an inlet and an outlet, the pump operably interconnected to a drive wheel via a shaft such that a rotational movement of the drive wheel results in substantially vertical displacement of the shaft to provide power to the pump; the fluid pick-up orifice being interconnected to the pump by a conduit for transmitting fluid from the fluid pick-up orifice to the pump; wherein the pump is positioned above the pick-up orifice and the conduit comprises at least one valve substantially preventing flow of a fluid in a direction away from the pump.
[0012] In one embodiment, a floor cleaning tool for cleaning a surface is provided, the floor cleaning tool comprising a chassis comprising: a first tank for containing a cleaning solution, the first tank having a discharge port positioned to effect dispensing of the cleaning liquid therefrom; a second tank for receiving the cleaning solution following its being dispensed to the surface; and a mechanically-driven pump for removing the cleaning solution from the surface and discharging the collected cleaning solution into the second tank; a conduit for transmitting the cleaning solution from a collection point to the second tank, the conduit comprising at least one non-return valve for substantially preventing flow of the fluid away from the second tank. A rotatable trailing deck assembly is provided connected to the chassis and comprising a squeegee, the deck assembly being selectively detachable from the chassis. A main wheel assembly is provided comprising at least two wheels for supporting and moving the chassis, at least one of the wheels comprising a drive wheel with a rotational motion mechanism for converting the rotational motion of the drive wheel into reciprocal motion, and the drive wheel provided substantially directly beneath the pump and operably connected to the pump by a substantially vertical drive shaft.
[0013] It is an object of the present disclosure to describe an efficient and yet economical scrubber which can be manually operated. Other objects and advantages of the present disclosure will become apparent to those skilled in the art upon a review of the following detailed description of the preferred embodiments and the accompanying drawings.
[0014] According to varying embodiments of the present disclosure, a floor cleaning tool having a mechanically operated pump is disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings, which are incorporated in and constitute part of the specification, illustrate embodiments of the present disclosure and together with the general description given above and the detailed description of the drawings given below, serve to explain the principle of the present disclosure.
[0016] FIG. 1 is a perspective view of an embodiment of a floor cleaning tool according to the present disclosure;
[0017] FIG. 2 is a partial schematic view of an embodiment of a floor cleaning tool according to the present disclosure;
[0018] FIG. 3 is a detailed perspective view of an embodiment of a floor cleaning tool according to the present disclosure;
[0019] FIG. 4 is a bottom perspective view of a feature of an embodiment of a floor cleaning tool according to the present disclosure;
[0020] FIG. 5 is phantom perspective view of an embodiment of a floor cleaning tool according to the present disclosure; and
[0021] FIG. 6 is a perspective view of a component of one embodiment of the present invention.
[0022] It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the disclosure or that render other details difficult to perceive may have been omitted from these drawings. It should be understood, of course, that the present disclosure is not limited to the particular embodiments illustrated in the drawings.
DETAILED DESCRIPTION
[0023] Varying embodiments of the present disclosure are described herein with reference to the drawings. It is expressly understood that although FIGS. 1-6 depict certain embodiments of a floor cleaning tool, the present disclosure is not limited to those specific disclosed embodiments.
[0024] Referring to FIGS. 1-2 , there is provided a floor cleaning tool 10 having a chassis 14 with main wheels 22 mounted on an axle 26 proximal a rearward portion of the tool 10 . The chassis 14 comprises a deck 66 comprising cleaning and fluid collection features as will be shown and described in more detail herein. In some embodiments, the chassis 14 is rotationally molded from one of a variety of plastic materials such as high density polyethylene. The chassis 14 is provided with a cleaning solution tank which extends from the back of the chassis 14 adjacent the main wheels 22 to the front of the chassis 14 , and occupies the majority or all of the lower portion of the chassis 14 . The cleaning solution tank holds cleaning solution 18 , which may be any liquid useful for cleaning, including water, soap, and/or cleaning chemicals. In various embodiments of the present disclosure, the position, size, and shape of cleaning solution tank 18 can be modified as desired and/or convenient; neither the parameters nor the location of the cleaning solution tank 18 is critical to the present disclosure.
[0025] FIG. 2 is a side view of a fluid application and recovery system according to one embodiment of the present invention, and shown in isolation with respect to certain additional features of the present disclosure. As shown, a recovery pump 40 is provided for translating fluids. The recovery pump 40 comprises a mechanical pump driven by ground-induced rotational movement of a drive wheel 31 . Additional wheels 30 , 32 are provided for supporting the device and/or providing rotational power to the drive wheel 31 and associated pump 40 . Accordingly, movement of the device along a surface provides the power required to drive a pump 40 and draw fluid from a ground or floor surface. The pressure differential created by the pump 40 draws a fluid from the floor via recovery line 52 which is operatively associated with a pick-up orifice 48 located proximal to the floor. Clean fluid 47 dispensed from the device 10 contacts and cleans the floor as it is converted to dirty fluid 44 and subsequently transported or picked up by the pump 40 and conveyed to a recovery tank 28 or similar receptacle.
[0026] In various embodiments, one or more conduits between a pick-up orifice 48 and a recovery tank 28 are provided with means for maintaining sufficient pressure and preventing back-flow in the conduit(s). For example, in certain embodiments, one or more check valves 42 , 50 are provided for reducing or eliminating the risk of back-flow or pressure loss in the line 52 . Check valves preferably comprise valve features permitting only unidirectional flow of the fluid 44 (i.e. from the floor/orifice 48 to the recovery tank 44 ). It will be recognized that where pump pressure is lost or where fluid is allowed to drain downwardly in line 52 , such as by the force of gravity, pump 40 may become ineffective at removing fluid 44 as intended. It is also an object of the present invention to prevent fluid disposed between inlet 48 and pump 40 to simply drain out of the device when the tool is brought to rest. Accordingly, the present invention contemplates providing at least one valve feature for reducing or eliminating this risk. As shown, a first valve 50 is provided proximal the inlet orifice 48 . A second valve 42 is provided proximal to and downstream of the pump 40 . In various embodiments, valves 42 , 50 comprise valves that allow for fluid flow in one direction (i.e. toward the reservoir 28 ), and substantially prevent back flow or fluid flow in a reverse direction. Such valves may comprise check valves, non-return valves, clapper valves, one-way valves or various other valve types that provide the described function(s).
[0027] As shown in FIGS. 2-3 , cleaning fluid is dispensed via clean fluid conduit 47 preferrably directly in front of a squeegee and within an area defined by the deck assembly 66 . Dispensation of fluid through the clean fluid conduit 47 is controlled or metered by one or more control means 16 provided on or proximal the chassis 14 . As will be recognized by one of skill in the art, devices 10 of the present invention are useful for cleaning up spills and liquids from external or preexisting sources. Additionally, however, devices 10 of the present invention comprise the ability to dispense cleaning fluid(s) to a surface, perform cleaning functions (e.g. scrubbing, wiping, etc.), and collect and store such fluids after they have performed their intended function. Accordingly, the present invention comprises a multi-purpose floor cleaning device.
[0028] Referring now to FIG. 1 , the cleaning device 10 comprises various features for assisting in various cleaning tasks. For example, the depicted embodiment of the cleaning device 10 is provided with a storage unit 12 . Storage unit 12 comprises a selectively removable device provided with a handle 13 and one more storage areas 15 for containing various products, including but not limited to, cleaning products, tools, waste products, etc. In certain embodiments, the storage unit 12 is provided as a replacement to and in lieu of a spent fluid collection tank. For example, and as shown in FIG. 1 , the device 10 may be provided in a state wherein the pump and the deck 66 are inactive, and the device 10 is essentially a caddy or cart. The deck 66 is shown in an elevated position in FIG. 1 , wherein it has been rotated upward and out of contact with the floor or ground surface upon which the device 10 rests. A user-operated control 16 is provided on an exterior of the chassis 14 such that dispensation of cleaning fluid can be selectively controlled. The control 16 is contemplated as being any one or more of known devices useful for starting, stopping, and/or metering flow of a fluid. The control 16 may, for example, control a ball valve for initiating and terminating fluid to be dispensed. The device 10 further comprises attachment features, such as a shelf portion 17 for receiving and supporting a mop, broom, or similar cleaning device.
[0029] A port 3 is provided on a portion of the chassis 14 . The port 3 may serve as a drain or input for fluid for one or both of the clean fluid storage tank and the spent fluid storage tank. In one embodiment, the port 3 comprises a simple drain for removing unused clean fluid from the clean fluid storage tank, such as may be desirable when the device 10 is to be stored or transported and emptying of the device 10 is preferred.
[0030] As shown in FIG. 1 , a user interface portion 2 comprises a simply handle for grasping and maneuvering the device 10 . The interface portion 2 is rotatable and detachable at the locating of fasteners 4 . Fasteners 4 comprise, for example, simple threaded fasteners.
[0031] Referring to FIGS. 2 and 5 , the chassis 14 further comprises a recovery tank 46 . Preferably, recovery tank 28 is removably mounted on chassis 14 and is equipped with a handle to facilitate removal of the recovery tank 28 from the chassis 14 , i.e. when disposing of the contents of recovery tank 28 . The recovery tank 28 rests on top of solution tank 18 . The upper portion of recovery tank 28 has an inlet opening (not shown) through which dirty cleaning solution is pumped into recovery tank 28 during operation of floor cleaning tool 10 .
[0032] To further simplify attachment and detachment of deck assembly 66 to and from trailing arm 142 , large, easily manipulated squeegee mount knobs 92 a , 92 b are provided. Squeegee mount knobs 92 a , 92 b removably engage deck assembly 66 . In some embodiments, squeegee mount knobs 92 a , 92 b comprise threaded fasteners. In other embodiments, squeegee mount knobs 92 a , 92 b comprise snap-in fasteners or other known quick connect/disconnect fasteners.
[0033] FIG. 3 is a rear perspective view of a deck 66 according to one embodiment. The chassis 14 is shown in phantom, such that the drive wheel 31 and associated features are more visible. As shown, the drive wheel 31 is provided in a recess 145 of the chassis such that the drive wheel is bordered by the chassis on three sides. The drive wheel 31 is thus accessible to user from a rear of the device 10 without needing to disassemble the chassis 14 . Additionally, the drive wheel 31 and associated components are protected by the chassis on three sides, and increased storage volume for clean or spent fluids or various additional are components is provided. In certain embodiments, the axle 26 of the drive wheel 31 is provided internal to the recess or void space 145 in the chassis 14 . As shown in further detail in FIG. 6 , the axle 26 and wheel yoke 312 are driven by eccentric hubs 306 of the drive wheel 31 , which drive upwardly extending shaft 314 which is interconnected to the pump unit. The positioning of the centrally located drive wheel 31 and surrounding components and position of the chassis 14 provide for a compact unit with a lower center of gravity than known devices, while also providing for additional storage volume(s). The placement of the drive wheel 31 is one aspect of the invention that enables the device 10 to occupy a minimal amount of space while providing its intended cleaning functions and advantages over the prior art.
[0034] As shown, deck 66 is selectively connected to the chassis 14 via trailing arm 142 , which may be bolted or similarly secured to the chassis 14 via fasteners. A cut-out or recess 145 is provided in the chassis, allowing user-access to, for example, the drive wheel 31 as well as the connection points and fasteners 143 for attaching and removing the deck 66 . A tongue or extension 90 extends from the trailing arm 142 . One or more pivot points may be provided in the extension 90 to allow the deck 66 to rotate or swivel.
[0035] As shown, a deck 66 is selectively interconnected to a remainder of a floor cleaning device 10 . The device 10 comprises an aft extension 90 with slotted recesses for receiving and securing fastening members 92 a , 92 b to secure the deck 66 to the aft extension 90 . In various embodiments, the deck 66 is pivotally mounted on the extension 90 and/or the extension 90 is pivotally provided on the chassis 14 of the device 10 . Thus, in at least some embodiments, the deck 66 is at least one of removable from a remainder of the device 10 and rotatable to a position wherein the deck 66 is not in contact with a floor or ground surface.
[0036] A dispensing outlet (not shown) is located at a low point of the solution tank 18 —preferably at the lowest point of gravitational potential energy of the solution tank 18 . The dispensing outlet is detachably connected and in fluid communication with solution inlet plumbing 34 . Cleaning solution in the solution distribution trough 18 is released directly onto the floor in some embodiments, or onto a floor pad 62 of deck assembly 66 in other embodiments, including the one shown in FIG. 4 . Floor pad 62 is preferably an abrasive pad or brush. In certain embodiments, cleaning solution is not pumped out of solution tank 18 , but rather flows out of solution tank 18 due to gravity. In some embodiments, a dispensing valve located in the dispensing outlet or elsewhere in the cleaning solution flow path is used to start and stop the flow of cleaning solution out of solution tank 18 .
[0037] FIG. 4 is a bottom perspective view of a deck 66 according to one embodiment of the present invention. The deck 66 , which may be provided in combination with various embodiments and features provided herein, comprises a debris pad 62 . A squeegee 70 is provided on a lower portion of the deck 66 , the squeegee comprises a trailing portion to clear any debris and/or water not picked up by additional system components. One or more quick release latches are provided for ease of removal and application of squeegee blade 70 . In certain embodiments, one or more articulating debris pads are provided, the articulating debris pads being provided for additional cleaning. In the depicted embodiments, a single debris pad 62 is provided, the debris pad comprising various sections forming a lattice-type structure with one or more void spaces 63 provided therein. A pickup valve assembly 68 comprising a pick-up orifice is provided on a lower portion of the deck 66 and proximal a rear portion thereof. In various embodiments, the assembly 68 is provided sufficiently proximate to a ground surface such that the pump force is capable of removing fluid(s) from the ground surface through, for example, a vacuum force applied by a pump. One or more check valves, as previously described, may be provided in combination with the assembly 68 to prevent back-flow of fluid, particularly when the device 10 is brought to rest and/or the pump is not active.
[0038] Embodiments of the present invention contemplate an assembly 68 comprising an aperture provided with a filter or similar device to enable fluid transport through the aperture to prevent large-scale particles and debris from becoming drawn into the device. In various embodiments, the assembly 68 is provided such that the planar area of the orifice is substantially parallel to a floor or ground surface being cleaned. The planar entrance area of the orifice is provided between approximately 0.01 inches and 4.00 inches above a ground surface. Preferably, the planar entrance area of the orifice is provided between approximately 0.05 and 0.075 inches above a ground surface.
[0039] Referring now to FIG. 4 , deck assembly 66 is supported on a pair of wheels 94 which, in some embodiments, may be raised or lowered by a lift mechanism of one of several types well known in the art. The deck assembly 66 supports squeegee blade 70 , which contacts the floor or surface being cleaned. In some embodiments, two or more squeegee blades may be attached to deck assembly 66 . Pickup valve assembly 68 is positioned in the center and towards the rear of deck assembly 66 , and comprises an orifice as a fluid pickup point located adjacent the floor immediately in front of squeegee blade 70 . In embodiments having two or more squeegee blades attached to deck assembly 66 , the recovery pickup point may be located between two squeegee blades for improved suction.
[0040] In certain embodiments, the deck assembly 66 comprises quick-connect features for one or more pads 62 . Pads 62 of the present invention comprise, for example, commercially available 3M® Easy Trap Duster pads, for securing to a lower region of the deck assembly 66 . Quick connect features provided on the lower surface of the deck assembly 66 include, but are not limited to, hook and loop pads, clips, and various fasteners useful for securing a cleaning pad 62 to the assembly 66 .
[0041] FIG. 5 is a perspective view of a floor cleaning device 10 of one embodiment of the present invention. As shown, the device 10 comprises control means 2 , such as a handle, in operable communications with a chassis 14 . The chassis 14 is provided on wheels 30 a , 30 b . A recovery deck 66 is provided as a trailing member and in fluid communication with a pump drive assembly internal to the device 10 . A recovery bucket 28 comprises a basin to collect and store dirty liquids recovered from a floor or surface by the pump. The recovery bucket 28 comprises a removable feature such that it may be manually lifted and removed from the chassis 14 for emptying, cleaning, replacement, etc. In certain embodiments, the recovery bucket 28 comprises mop tray or wringer 74 . The mop wringer 74 is provided for use with a mop 76 , which is selectively securable to the chassis 14 in the embodiment of FIG. 5 . Mops and similar devices are contemplated for use in cleaning operations, and may be particularly useful for cleaning surface and locations that the device 10 may not be able to access (e.g. corners and areas underneath certain objects). The upper portion of the recovery bucket 28 comprises tray and/or wringer features for receiving a mop head and further allowing contents to drain into the recovery bucket 28 . In the depicted embodiment, the recovery bucket 28 is provided in a central void 70 of the chassis 14 . Various embodiments of the present invention contemplate providing such a chassis 14 with an interior portion 70 that is void or partially void so as to accommodate various devices and features, including recovery bucket 28 and/or storage unit 12 (see FIG. 1 ).
[0042] As shown, the device 10 is capable of receiving a known or preexisting mop device 72 on a chassis 14 . The device 72 comprises receiving means, such as indentations, troughs, clips, etc. for receiving a mop. Such features are provided in addition to or in lieu of fluid dispensing means shown and described herein. In one embodiment, a mop is provided for additional cleaning functionality and is useful in, for example, situations where the device 10 may have missed portions of a floor to be cleaned and spot cleaning with the mop is desirable. Additionally, a wringer or mop tray 72 is provided for supplying the mop with fluid and/or cleaning the mop after and during use.
[0043] As shown in FIG. 5 , a feature of the present invention comprises a novel attachment member 100 . Attachment member 100 is capable of at least two modes of use. A first mode is provided wherein a cylindrical portion of the attachment member is disposed in a recess and a hook portion extends outwardly therefrom. In this first mode, various features such as a “wet floor” sign 78 may be hung from the attachment member 100 . In a second mode, the attachment member 100 is attached to an additional device, such as mop 76 . The cylindrical portion of the attachment member 100 comprises a removable clip that can be selectively secured to various features, such as the elongate shaft of a mop 76 . Once secured, the hook portion extends outwardly therefrom and may be placed or inserted into the chassis 14 , such that the mop 76 is supported thereon. It will be recognized, therefore, that the attachment member 100 comprises a single device that is capable of two different modes of use for storage and/or transport of articles.
[0044] Referring now to FIG. 6 , a mechanically driven pump 300 according to one embodiment is provided in fluid communication with the recovery tank (not shown). In the depicted embodiment, the pump 300 is a diaphragm pump, but in other embodiments other types of pumps, such as piston pumps or centrifugal pumps, are provided. A pump housing 302 is provided, the pump within the housing 302 being driven by a drive wheel 31 provided in rolling contact with a floor surface. The drive wheel 31 comprises eccentric wheel hubs 306 with an axle 26 supported on a frame or chassis. The hubs 306 are connected to a wheel yoke 312 , which is connected to a pump yoke 308 via a shaft 314 . The pump is actuated by movement of the wheel 31 and associated eccentric hubs 306 , which induces a reciprocating vertical movement of a cross-bar 316 which provides power to the pump. Vertical movement of the guide bar 316 is assisted by vertical guide slots 310 extending upwardly from the pump housing 302 . One or more coil springs 304 are provided on the pump yoke 308 to bias the pump and associated components.
[0045] Floor cleaning tools of the present invention are primarily intended to deliver and collect a controlled volume of cleaning solution from the floor during normal floor cleaning operations, and persons of ordinary skill in the art will appreciate that pumps and recovery tanks should be sized appropriately. However, other uses of floor cleaning tools will be readily apparent to persons of skill in the art. For example, floor cleaning tools of the present invention may be used to collect puddles and spills. To ensure that floor cleaning tools are useful for such applications, pumps and recovery tanks preferably have excess capacity, so that they can collect a greater volume of liquid, at a higher rate, than is required for normal floor cleaning operations.
[0046] In some embodiments, a cleaning solution tank is positioned above the pump and/or recovery tank, thereby raising the lowest point of the solution tank and enhancing the gravity-powered flow of cleaning solution from the cleaning solution tank. Other arrangements are possible. For example, in some embodiments, cleaning solution tank and recovery tank occupy horizontally adjacent positions; i.e., cleaning solution tank may be located forward of recovery tank on chassis, or cleaning solution tank may be located to one side of recovery tank on chassis. This facilitates access to both tanks, and reduces the overall height of floor cleaning tool. Removal of tanks for replacement, cleaning, emptying, and/or refilling are also simplified in such embodiments.
[0047] In various embodiments of the present invention, the sizes of cleaning solution tank, recovery tank, pump, and squeegee are selected based on the target market for the floor cleaning tool. For example, floor cleaning tools intended to be used commercially preferably comprise larger components than floor cleaning tools intended for household use, as commercial applications are likely to have significantly greater surface area to clean.
[0048] While various embodiments of the present disclosure have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present disclosure, as set forth in the following claims. Further, the invention(s) described herein are capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purposes of description and should not be regarded as limiting. The use of “including,” “comprising,” or “adding” and variations thereof herein are meant to encompass the items listed thereafter and equivalents thereof, as well as additional items.
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A compact machine for cleaning floors includes a solution tank and dispensing system for dispensing solution onto the surface to be cleaned, a deck assembly for guiding dirty solution to a recovery pickup point, a mechanically operated pump for collecting the dirty solution from the recovery pickup point, and a recovery tank for receiving the collected fluid.
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BACKGROUND OF THE INVENTION
The present invention relates to a new and improved construction of an automatic firing weapon having at least two cartridge magazines from which there can be conveyed loose cartridges into a common discharge or outfeed channel, and a device for switching the cartridge infeed from one cartridge magazine to the other.
With a weapon as is known from U.S. Pat. No. 3,043,198 a number of cartridge magazines or compartments are arranged in parallelism next to one another and in which there are stacked loose cartridges. Initially the cartridges are conveyed out of the compartment which is furthest from the center of the weapon. After emptying this compartment there is automatically opened the neighboring compartment situated closer to the center of the weapon. A drawback of this weapon is that it is not possible at any time to select the emptying of a given compartment, as such is required if there should be fired different types of ammunition in accordance with the relevant battle conditions.
Further, there is known a firing weapon from German Patent publication No. 471,398 in which two cartridge magazines or compartments can be inserted into two magazine chambers. In order to switch the infeed or delivery of cartridges from the first cartridge magazine to the second magazine, it is necessary that either the first cartridge magazine is empty or that it is ejected without being emptied, i.e. that the relevant magazine chamber is empty. If it is desired to then change-over from the second magazine to the first, then first of all the first cartridge magazine must be again inserted and the second either must be empty or ejected. A rapid change-over of the cartridge infeed from one magazine to the other and back again is therefore not possible.
SUMMARY OF THE INVENTION
Hence, it is a primary object of the present invention to provide an improved construction of automatic firing weapon equipped with at least two cartridge magazines which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.
Another object of the present invention aims at overcoming the aforementioned drawbacks and providing a weapon having at least two cartridge magazines wherein it is possible to select, at any time, the removal of cartridges from a predetermined magazine.
Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the invention contemplates that the switching device comprises mechanism which can be selectively adjusted into two positions and independent of emptying one of the cartridge magazines. By means of such adjustment mechanism the cartridges can be delivered, in one position of such mechanism, from one cartridge magazine into the delivery channel and at the same time are blocked in the other cartridge magazine.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a horizontal sectional view through the right side of an automatic firing weapon equipped with cartridge magazines i.e. a section along the line I -- I of FIG. 5 or FIG. 6;
FIG. 2 is a vertical sectional view taken along the line II -- II of FIG. 1;
FIG. 3 is a plan view of part of the firing weapon illustrated in FIG. 2;
FIG. 4 is a cross-sectional view taken along the line IV -- IV of FIG. 2;
FIG. 5 is a side view of the cartridge magazine of the firing weapon;
FIG. 6 is a cross-sectional view taken along the line VI -- VI of FIG. 5, showing a first position of a cartridge infeed device;
FIG. 7 is a partial sectional view, corresponding to FIG. 6, showing a second position of the cartridge infeed device; and
FIG. 8 is a schematic view of the hydraulic part or circuit of the cartridge infeed device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, according to the showing of FIG. 1 a housing 1 of the automatic firing weapon or gun is mounted to be elevationally displaceable upon two trunnions 2 in a turret, for instance an armored battle vehicle. A base or floor portion 3 is arranged to be rearwardly movable in any suitable and therefore not particularly illustrated manner in the housing 1. A barrel 4 possessing a cartridge chamber 5 is inserted into the base portion 3. A wedge-type breechblock 6 is vertically displaceable in the base portion 3.
The housing 1 possesses a rear housing portion 7 which essentially consists of a rectangular frame mounted upon a housing wall 8 extending perpendicular to the not particularly referenced lengthwise axis of the weapon and a first intermediate wall 9 parallel to the housing wall 8. The frame possesses second, third and fourth intermediate walls 12, 13 and 14 respectively. The third and fourth intermediate walls 13 and 14 are interconnected by a base or floor 15 directed perpendicular thereto. The second intermediate wall 12, according to the showing of FIGS. 2 and 3, has a rearwardly directed web 16 in which there are formed two slots 17 having guide grooves 18. Two thrust elements 19, each possessing a downwardly directed switching finger 20, engage into the guide grooves 18 and are thus displaceable in the slots 17. At the second intermediate wall 12 there are arranged two hydraulic cylinders 21 having the piston rods 22. At the third intermediate wall 13 there are attached two switches 23. The planes of symmetry of the slots 17 are located parallel to one another and at the same spacing to opposite sides of the lengthwise central plane of the weapon. In each of these two planes there is further located the lengthwise axis of the associated piston rod 22 and the lengthwise axis of an oppositely directed actuation component 24 of the neighboring switch 23. Further, there is located in each of the aforementioned planes the lengthwise axis of a cartridge transport device T R and T L respectively (the position of the components of the ammunition infeed of the weapon relative to the lengthwise central plane will be hereinafter indicated by the reference characters R (meaning right) and L (meaning left) associated with the corresponding reference numeral; in FIGS. 1 and 2 there is only shown the right transport device T R ).
According to the showing of FIGS. 1 and 2 the cartridge transport device T R possesses a sleeve 25 rotatably mounted in the first and second housing walls 9 and 12. In the sleeve 25 there is cut a helical- or screw-shaped slot 26. The directions of rotation of slot 26 are opposite to one another for the two transport devices T R and T L . A rod 27 secured in the base portion 3 extends into the sleeve 25. A cam or dog 28 connected with the rod 27 is guided in the slot 26. A connection element 29 is keyed to the sleeve 25 and is connected in driving relationship via a not particularly illustrated freewheeling coupling with a coupling collar 30 which is displaceable thereon. According to the showing of FIG. 2 the switching finger 20 of the corresponding thurst element 19 engages with the coupling collar 30. A shaft 31 is keyed with a bushing 32 which, in turn, is keyed with the hub 33 of a cartridge switching or indexing wheel 35 R possessing two four-tooth star wheels 34. The hub 33 is mounted at the third and fourth intermediate walls 13 and 14 of the housing and keyed with a sleeve 36 fixedly seated upon the shaft 31. A further sleeve 37 is displaceably mounted upon the end of the shaft 31 and extends rearwardly out of the housing.
On the one hand, two confronting end surfaces 30a and 32a of the bushing 32 and the coupling collar 30 and, on the other hand, two end surfaces 36a and 37a of both sleeves 36 and 37 are provided with teeth which can come into coupling engagement with one another. The sleeve 37 is subjected to the pressure of a spring 39 bearing against the housing wall 38. A handle 40 or the like connected with the sleeve 37 bears under the pressure of spring 39 against a stop 41 which retains the teeth of the sleeves 36 and 37 out of engagement with one another.
According to the showing of FIG. 3 a lever 42 is pivotable about a shaft 43 which is connected with the web 16. Lever 42 possesses two elongate holes 44 into each of which there engages a respective bolt 45 connected with its associated thrust element 19. The ends of the lever 42 are beveled or inclined at both sides. In the housing wall 10 there are displaceably mounted the securing bolts 48 exposed to the pressure of the springs 47.
The rear ends 46 of the hubs 33 of the switching wheels 35 R and 35 L , according to the showing of FIG. 4, are provided with a number of wedges 49 (if desired four) corresponding to the number of teeth or recesses of the star wheel 34. Two double-arm pawls 50 are pivotably mounted upon the shafts 51 secured in the housing rear wall 8. The arm 50a of each of the pawls 50 which is directed towards the associated switching wheel 35 R and 35 L possesses a tooth 52. At the other pawl arm 50b there is milled or otherwise suitable formed a surface 53. A spring 54 bears at a cover 56 and acts, through a bushing 55 displaceably guided therein, upon the associated pawl arm 50a. A leaf spring 57 is secured at the center of the weapon at the cover or cover member 56. The other end of the leaf spring 57 is attached at a positioning or transfer body 58 which is mounted upon a shaft 59 inserted into the housing rear wall 8.
According to FIGS. 1, 5 and 6 there are arranged at both sides of the rear housing portion 7 four cartridge magazines M 1 to M 4 . The cartridges P arranged in the magazines M 1 to M 4 are guided by the switching or indexing wheels 35 R or 35 L to an infeed plate 101 (see FIG. 4) provided with a recess 102 and are designated by double place index numerals, wherein the first numeral indicates the association with a magazine and the second numeral the sequence or position of the cartridge from the infeed plate 101. Each magazine M is bounded at the outside by struts 60, 61 arranged at right angles to one another and formed, for instance, by flat iron members. The inner boundary of the upper magazines M 2 and M 4 is formed by walls 10 of the rear housing portion 7, the lower edges of which are bent inwardly at an inclination in the form of cartridge guides 11, as shown in FIG. 6. At both sides of the weapon axis there are secured to the housing rear wall 8 plates 62 and rails 63 which are connected with such plates 62 so as to form the inner boundary of the lower magazines M 1 and M 3 . The end surfaces 64 of the plates 62 form guide surfaces for the cartridges and are provided with transversely situated guide ledges 100, 100a (see FIG. 2). The ends of the struts 60 a to 60 d are attached to a side wall 65 and the rear wall 8 of the housing 1. The struts 60 a to 60 d are interconnected by vertical rails 61 a , 61 b arranged at their inner side. Each rail 61 a is constructed to guide the cartridges at the conical portion of their sleeves and the rails 61 b to guide the base of the cartridges. Not particularly illustrated guides, corresponding in construction to the rails 61, are also secured at the housing walls 10.
According to the showing of FIG. 1 the rails 61 a and 61 b are beveled towards the inside and form a shoulder or projection 66. A base element or portion 67 (see FIGS. 5 and 6) of substantially U-shape is attached at an extension 9 a of the first intermediate wall 9 and at the rails 63 connected with the plates 62. A shaft 68 is rotatably mounted at the base element 67. Three rails 69, 70, 71 are keyed with the shaft 68 and mutually interconnected by side struts 99. The intermediate rail 70 is provided with a snap catch or lock 72 and can be locked with the strut 60 d . The rail 70, the rail 63 opposite thereto, which rail 70 continues upwardly in a rail 73 connected with the strut 60 d and the plate 62 possess a groove 74 as shown in FIG. 1.
A downwardly open frame 75 having legs 76 is inserted into the struts 60 a , 60 b . The symmetry plane of the frame 75 is parallel to the housing rear wall 8. The legs 76 of the frame 75, according to the showing of FIG. 1, possess U-shaped guide grooves 76 a facing one another. A slide 77 is displaceable in the frame 75 in that two laterally arranged ledges 85 engage in the guide grooves 76 a of the frame legs 76. The slide 77 has an upper portion 77 a constructed as a frame and a lower portion 77 b . Side legs 78 a of a frame-shaped guide portion 78 which is open at one side are articulated at the lower slide portion 77 b . A further guide portion 79 (see FIG. 6) is articulated at two ledges 80 which protrude inwardly from the lower slide portion 77 b . The guide portions or guides 78 and 79 are subjected to the pressure of two respective bushings 82 loaded by springs 81, and which bushings are displaceably arranged in blindhole bores of the projections 83 and 84 of the slide portion 77 b . At the left-half of the showing of FIG. 6 there is illustrated a spring 81 and bushing 82 associated with the guide portion 78, whereas the right-half of FIG. 6 illustrates the other spring 81 a and bushing 82 a associated with the guide portion 79.
FIG. 5 shows that to both sides of the housing 1 two respective levers 86, 88 are pivotable about shafts 87, 89 connected with the housing wall 65. Piston rods 91 and 93 of two hydraulic cylinders 90 and 92, respectively attached to the housing wall 65 are hingedly connected with the levers 86 and 88 respectively. At the ends of the levers 86 and 88 there are hingedly secured (see FIG. 6) the plates 94 and 95 respectively associated with the magazines M 1 , M 2 and M 3 , M 4 respectively. The plate 95 connected with lever 88 possesses cams or dogs 96 which engage with the grooves 74 of the guides 70, 73 and 62, 63. A further hydraulic cylinder 97 (FIGS. 5, 6) is attached to the strut 60d and its piston rod 98 extends between both of the projections 83 of the slide 77 and is connected therewith.
According to the showing of FIG. 8 the hydraulic cylinders 21 R and 21 L arranged to the right and left of the lengthwise central plane of the weapon each have operatively associated therewith a two-way valve 103. A respective connection or stud of valves 103 is coupled with a supply line 104 connected with a not particularly illustrated pump. A further connection of the valves 103 is coupled with a return flow line or conduit 105 leading to a likewise not particularly illustrated oil reservoir. Each of the cylinders 21 R and 21 L is connected by a conduit or line 106 with a respective further connection of the associated valve 103. The pistons 22 of these cylinders 21 R and 21 L are loaded by springs 116. Terminal switches 23 L , 23 R are arranged to the left and right and are actuatable via the lever 42 by means of the piston rods 22 of the cylinders 21 L , 21 R .
Two valves 103 I and 103 II are operatively associated with each hydraulic cylinder 97 R and 97 L arranged to the left and right of the lengthwise central plane of the weapon. A respective connection of each one of the valves 103 I , 103 II belonging to the corresponding cylinder 97 R and 97 L is connected with the supply line 104 and with the return flow 105. A third connection of each of both valves 103 I is connected by a conduit or line 107 with the one side of the corresponding cylinder 97 R and 97 L , and a third connection of each of both valves 103 II is connected by a conduit or line 108 with the other side of the corresponding cylinders 97 R and 97 L . Mounted in both of the conduits or lines 107 and 108 are check valves 109 and 110 which can be opened. The check valve 109 is connected by means of a conduit 111 with conduit 108, and the check valve 110 is connected by means of the conduit 112 with the conduit 107. Two terminal switches, which can be actuated by a push button or key 115 connected with the associated piston rod 98 of the corresponding cylinder 97 R and 97 L are designated by reference character 114.
Actuation of the cylinders 90 L , 90 R , 92 L , 92 R , which are accordingly arranged to the left and right, is likewise controlled by a respective valve 103. A respective connection of each of the valves 103 is coupled with the supply line 104 and the return flow line 105. A third connection is connected via the conduit 119 with that side of the corresponding cylinder 90 L , 90 R , 92 L , 92 R which faces the complete end surface of the associated piston 91, 93. The other side of each cylinder 90 L , 90 R , 92 L , 92 R , at which there is impinged the surface of the piston which is reduced by the cross section of the piston rods 91, 93, is likewise connected by means of a conduit 118 with the supply line 104.
Having now had the benefit of the foregoing description of the apparatus of the invention, its mode of operation will be considered and is as follows:
According to the showing of FIG. 6 the slide or slide member 77 shown at the left is located in its lower position where its portion 77 b closes the magazine M 1 . The guide portion 78 at the left, under the action of the spring 81, is held pivotedout in that position where its end bears at the base of the groove 85 forming a stop. In this position the guide portion 78 is parallel to the inclined guide 11 of the housing and is at a spacing from such which essentially corresponds to the diameter of a cartridge P. It will be seen the cartridge P 22 bears at the toothed rim of the switching or indexing wheel 35 L and at the guide portion 78. A cartridge P 21 is held in a preparatory position between two teeth, in a recess of the switching wheel 35 L , at the guide surface 64. Six cartridges P 11 to P 16 are stacked above one another in the magazine M 1 . The uppermost cartridge P 11 bears at the slide portion 77 b and retains the guide portion 79 in its pivoted-in position against the pressure of the spring 81 a .
The slide 77 at the right is located in its upper position where passage of cartridges P 41 , P 42 etc. from the magazine M 4 to the switching wheel 35 R is blocked and the guide portion 78 bears against slide portion 77 b . A cartridge P 31 dispensed from the magazine M 3 is retained in preparatory position by the switching wheel 35 R at the guide surface 64. Under the action of a force exerted by the cylinder 92 R via the lever 88 and the plate 95 upon the cartridges P 33 to P 37 located in the magazine M 3 , the cartridge P 32 bears against the teeth of the switching or indexing wheel 35 R and at the guide portion 79 which has been rocked-out under the force of the spring 81 a .
The cams or dogs 96 of the plate 95 are spaced from the base portion 67 at a distance which is somewhat greater than the diameter of a cartridge P. This free space is then used as a cartridge reserve space when there is rapidly switched to the infeed of ammunition from the magazine M 4 . In this case the righthand located slide 77 is lowered until it and the six cartridges P 32 to P 37 are located in the same position as the cartridges P 11 to P 16 in the magazine M 1 and the left-hand slide 77 of FIG. 6. The cartridges P 41 , P 42 etc. are stacked in the magazine M 4 and beat upon the guide portion 78.
With the valve positions as shown in FIG. 8, the cylinders 90 L , 90 R , 92 L , 92 R are connected with the return flow line or conduit 105 and the pistons together with the piston rods 91, 93 exert, via the levers 86, 88 with the plates 94, 95, a switching or indexing force upon the cartridges located in the magazine M 1 to M 4 .
When the lever 42 is located in the position of FIG. 3 then the switching or indexing wheel 35 R is coupled, i.e. the end teeth of the coupling collar 30 R and the sleeve 32 R are engaged with one another. The switching wheel 35 L is uncoupled. To establish the ready for firing condition the barrel 4 together with the base portion 3 are moved rearwardly at increased speed by a conventional piston which thus has not been shown in the drawing. Due to the movement of the cam 28 connected with the rod 27 in the slot 26 of the sleeve 25 the latter, and thus also the connection element 29, the coupling collar 30 and the switching or indexing wheel 35 R are rotated in clockwise direction (viewed in the showing of FIG. 6) through an angle of 90°. Consequently, the cartridge P 31 is moved out of the preparatory or waiting position along the guide ledges 100, 100a, appearing in FIG. 2, to the center of the weapon onto infeed guide member 101 (FIG. 4).
At the beginning of the rotation of the switching wheel 35 R the lever 50, appearing at the right of FIGS. 2 and 4, is rocked in counterclockwise direction (viewed in FIG. 4) under the action of the tooth or wedge 49 1 engaging at its tooth 52. When the wedge 49 1 has moved through past the tooth 52, then the lever 50, under the action of the spring 54, is again rocked back into the shaded position of the drawing where the tooth 52 bears at the cylindrical portion of the hub end 46. During the further movement the base of the cartridge P 31 comes into contact with the positioning or transfer body 58 located in the rest position illustrated in broken lines in FIG. 1 and rocks such, while overcoming the bending force of the spring 57, about the shaft 59. At the end of the rotation of the switching wheel 35 R the tooth 52 bears against the flank of the tooth or wedge 49 2 and engages therebehind. Further rotation of the switching wheel 35 R is prevented in that the cartridge P 31 at the end of its movement in the recess 102 of the infeed guide member 101, which takes place without a drive by the switching wheel 35 R , rotates the positioning body 58 to such an extent that such engages beneath the surface 53 of the lever 50 and locks the same.
During the rotation of the switching wheel 35 R the cartridges P 32 to P 37 which are stacked in the magazine M 3 are raised under the action of the indexing or feed force transmitted by the plate 95, whereby the cartridge P 32 is deflected by the guide portion 79 to the switching wheel 35 R (FIG. 7). Due to guiding of the plate 95 in the grooves 74 (see FIG. 5) there is achieved the result that such, during its upward directed cartridge feed or conveying movement in the magazine M 3 , engages at that location of the cartridges where there is located the center of gravity. When the cartridge P 31 , as shown in FIG. 4, has reached the central position, then the base element 3 together with the barrel 4 (FIG. 1), under the action of a recoil spring which is tensioned or biased during its return movement and has not been shown in the drawing, begin to again move forwardly back into the starting position. During this movement the sleeve 25 is again rotated back through an angle of 90° by the cam 28 of the rod 27, wherein, however, this rotational movement is not transmitted to the switching or indexing wheel 35 R . During the forward movement of the base element 3 together with the barrel 4 the cartridge P 31 is propelled in further not particularly illustrated manner forwardly into the cartridge chamber 5 of the barrel 4. When the base of the cartridge P 31 has moved away from the positioning or transfer body 58, such rocks, under the action of the leaf spring 57, back into the rest position. Consequently, the blocking of the lever 50 is released, so that now under the action of the spring 54 such secures the switching wheel 35 against rotation.
After firing of the cartridge P 31 the base or floor element 3 together with the barrel 4 again moves back under the action of the forces of the gas which are transmitted via the base of the cartridge sleeve to the base element 3. After opening of the breechblock the empty cartridge sleeves are ejected and the switching wheel 35 R is again rotated in clockwise direction through 90° in the manner already described (see FIG. 6), and thus, the further cartridge P 32 is conveyed to the center of the weapon on the infeed guide member 101.
If ammunition should be fired from a magazine M 1 , M 2 located at the left, then the switching wheel 35 R must be uncoupled from its drive and the switching wheel 35 L must be coupled with its drive mechanism. If, for this purpose, the valve 103 of the cylinder 21 L is displaced out of the position illustrated in FIG. 8, so that the spring 117 is tensioned, then the cylinder 21 L is connected with the supply line 104. The piston with the piston rod 22 L displaces the left thrust element 19, and therefore also the left coupling collar 30 rearwardly opposite to the firing direction S (viewed in FIG. 3) and rocks the lever 42 in the counterclockwise direction about the shaft 43, whereafter such is fixed in its new position by the bolt 48. The rocking lever 42 displaces the right thrust element 19 together with the right coupling collar 30 towards the front, so that its teeth and those of the sleeve 32 of the switching wheel 35 R are brought out of engagement. At the same time there is established the driving connection of the coupling collar 30 L with the switching wheel 35 L . During the movement of the left thrust element 19 there is activated the terminal switch 23 L , so that the valve 103 associated with the cylinder 21 L , under the pressure of the spring 117, again assumes the position illustrated in FIG. 8. Since the cylinder 21 L is now connected with the return flow line 105, the spring 116 can again move the piston together with the piston rod 22 back into the rest position.
The cartridges from the magazine M 1 and M 2 are conveyed by the switching wheel 35 L , driven in the counterclockwise direction, towards the center of the weapon onto the infeed guide member 101.
When the switching wheel 35 L should have delivered thereto cartridges P 1 from the magazine M 1 , then, the left slide 77 must be moved upwardly out of the position of FIG. 6. For this purpose the valve 103 II associated with the cylinder 97 L is displaced out of the position according to FIG. 8, against the pressure of the spring 117, so that then the conduit or line 108 is connected with the supply line 104 and the piston engaging at the slide 77 with the piston rod 98 are moved upwardly. Since pressure now also appears in the line or conduit 111, the check valve 109 is opened, and the oil displaced out of the cylinder 98 L can flow through the line or conduit 107 and through the valve 103 I to the return flow line 105. At the end of the stroke of the piston rod 98 the key or actuator element 115 actuates the terminal switch 113, and the valve 103 II can be moved by the pressure of the spring 117 back again into its original position. The line or conduit 108 is now again in flow communication with the return flow line 105, so that pressure no longer prevails in the conduit 111 and the check valve 109 prevents the return flow of oil out of the cylinder 97 L . Since now also the check valve 110 blocks the return flow out of the cylinder 97 L . the piston together with the piston rod 97, and therefore also the left slide 77, remain hydraulically locked in the upper position shown in broken lines in FIG. 8.
The operation of loading the magazines M 1 to M 4 will be explained hereinafter by way of example with respect to the magazine M 3 . The valve 103 located in the position of FIG. 8 and associated with the cylinder 92 R is shifted. After such adjustment the spring 117 is tensioned and both faces of the piston are connected with the supply line 104. Consequently, the piston with the piston rod 93 move in a direction opposite to the cartridge indexing or feed direction into a position designated hereinafter as the reloading position. Then, the right side of the magazine M 3 with the three rails 69, 70, 71 is opened by rocking about the right shaft 68. Thereafter, four cartridges P are introduced into the magazine M 3 and after renewed adjustment of the valve 103 these cartridges are raised by the action of the lever 88 until the cartridge P 31 bears against the switching wheel 35 R and the lowermost cartridge is located at the height of the strut 60 d . The lever 40 (FIGS. 1, 2) is now moved away from the stop 41 so that it is pushed forwardly together with the sleeve 37, under the action of the spring 39, and couples with the sleeve 36 and thus with the switching wheel 35 R which is disconnected from its drive mechanism.
During rotation of the lever 40 and the switching wheel 35 R coupled therewith through 90° in the clockwise direction (viewed in the showing of FIG. 6) the cartridge P 31 is engaged by the switching wheel 35 R and conveyed into the waiting or ready position illustrated in FIG. 6. Thereafter, the right lever 88 is again moved back into the reloading position and a pawl which has not been particularly shown in the drawing prevents the cartridges P 32 to P 34 from falling back. After three further cartridges P 35 , P 36 , P 37 have been loaded into the magazine M 3 , there is exerted an indexing or feed force upon the magazine contents P 31 to P 36 by renewed adjustment of the valve 103, associated with the cylinder 92 R , into the position of FIG. 8. Thereafter, the lever 40 is brought out of engagement with the sleeve 36, rotated back through 90° into its starting position and placed against the stop 41.
While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims. ACCORDINGLY,
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An automatic weapon equipped with at least two cartridge magazines from which loose cartridges can be conveyed into a common discharge channel, and a device for switching the cartridge infeed from one cartridge magazine to the other. The switching device embodies mechanism which can be selectively adjusted into two positions independent of emptying of one of the cartridge magazines. By means of the mechanism the cartridges in each instance can be fed, in one position of the mechanism, from the one cartridge magazine into the discharge channel and at the same time are blocked in the other cartridge magazine.
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BACKGROUND AND SUMMARY OF THE INVENTION
[0001] The invention relates to a modular construction system for producing a plurality of design variants of a roof module and to a method for producing such roof modules.
[0002] Modular production techniques are being increasingly used in motor car construction, wherein certain component groups are separately joined away from the main production line and then incorporated as a finished module again into the main production line. In particular, the production of roof modules according to this principle can be derived from the prior art as generally known. A plurality of roof variants is generally offered for a motor car type, for example solid roofs, sliding roofs, panoramic roofs and the like. To date the roof modules for these design variants have also differed in how they were connected to the rest of the motor car shell. Panoramic glass roofs for example are generally stiffened with a sheet metal frame and adhesively bonded into the shell from above. Other roof variants are joined to the shell from below and often require additional assembly parts and greater assembly expenditure.
[0003] For different roof variants of a motor car, therefore, it is disadvantageous that a plurality of assembly stations must be provided in the main production line as each roof variant, as described, is connected to the shell of the motor car in a different way.
[0004] Exemplary embodiments of the present invention provide a modular construction system and a method for producing a roof module, with which different design variants of roof modules can be produced that can be connected to a motor car shell in the same way.
[0005] Such a modular construction system serves for the production of a plurality of design variants of a roof module for a motor car. In this regard, a plurality of design-variant-specific adapter elements and a plurality of design-variant-specific planar elements are provided. By means of respectively at least one adapter element a respective planar element can be connected to a frame, forming a roof opening, in particular of a shell of the motor car. The adapter elements create a uniform connection interface between the roof and the shell in such a way that all roof modules that can be produced using the modular construction system can be connected to the motor car shell in the same way. It is thus no longer necessary—as known from the prior art—for each design variant to have its own installation station for the roof module in the motor car shell. Instead, all different modules can be incorporated in the same way into the shell. Both production time and production costs can thereby also be advantageously spared.
[0006] The design-variant-specific planar elements hereby include preferably planar elements for sliding roofs and/or panoramic glass roofs and/or lifting and sliding roofs and/or solid roofs. All common design variants of motor car roofs can thereby be advantageously realized by means of one and the same modular construction system. A design-variant-specific cover part is thereby produced from the combination of at least two respective planar elements.
[0007] The design-variant-specific adapter elements are preferably formed as frames. It is particularly preferable for the adapter elements to be separated into a front and a rear part frame that abut or overlap in the region of the B pillar of the motor car. In order to achieve an additional stiffening of the roof it is possible for an additional transverse reinforcing element to be provided in this area. A respective design-variant-specific cover part is also preferably separated in the region of the B pillar into a front and rear planar element, as in particular the rear region of the cover part often has no differences between different design variants. For example, a sliding roof and a lifting and sliding roof have the same rear planar element. Accordingly, the front planar elements comprising the actual sliding roof or lifting and sliding roof function must be differently formed in the two design variants.
[0008] In a further embodiment of the invention a plurality of design-variant-specific functional elements are provided which can be connected to at least one adapter element and/or one planar element. It can hereby be a matter of the actual cover mechanism for moving a sliding roof, an electric drive for movable parts of the roof, window shades, wind deflectors, guide rails or similar.
[0009] The invention further relates to a method for producing a roof module for a motor car from a plurality of design variants. Initially, a frame forming a roof opening is provided, in particular of a motor car shell, and then a planar element is selected from a plurality of design-variant-specific planar elements depending upon the desired design variant. In order to connect the planar element to the frame, at least one adapter element assigned to the selected planar element is selected in the next step from a plurality of design-variant-specific adapter elements and the planar element is connected to the frame by means of said adapter elements. The connection of adapter elements and planar elements is preferably thereby carried out by adhesive bonding.
[0010] As already described in relation to the modular construction system, the assembly of roof modules of different design variants on the motor car shell can be made uniform so that the number of necessary work stations in the main production line can be reduced.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
[0011] The invention and its embodiments will be described in greater detail below by reference to the drawings, in which:
[0012] FIG. 1 shows a frame of a motor car shell structure for incorporation of a roof module produced with an exemplary embodiment of the inventive modular construction system;
[0013] FIG. 2 shows adapter elements for an exemplary embodiment of an inventive modular construction system;
[0014] FIG. 3 shows functional elements for an exemplary embodiment of an inventive modular construction system and
[0015] FIG. 4A-4C show design-variant-specific planar elements and cover parts formed therefrom for an exemplary embodiment of an inventive modular construction system.
DETAILED DESCRIPTION
[0016] The shell of a motor car forms—as shown in FIG. 1 —a frame 10 for receiving a roof module. This comprises two longitudinal beams 12 and two transverse beams 14 .
[0017] In order to be able to provide different design variants of the roof module—as shown in FIG. 2 —adapter elements 16 , 18 are connected to the frame 10 formed as part of the shell. The adapter elements 16 , 18 are thereby formed as frame-like plastic elements which respectively extend approximately over half of the longitudinal extension of the roof module, are aligned and thus separated in the installation position of the roof module approximately in the region of the B pillar of the motor car. The frame-like adapter elements 16 , 18 respectively comprise large openings 16 a, 18 a that can optionally be covered in a transparent or openable manner. Likewise, in the region of the B pillar and thus between the adapter elements a glass element 20 can be arranged for additional reinforcing of the roof module. The adapter elements 16 , 18 serve firstly for the further stiffening of the roof module and secondly in particular for connection of different planar and functional elements to the frame 10 . For all design variants of the roof module a uniform connection geometry to the shell is provided by the adapter elements 16 , 18 , whereby all design variants can thereby be connected in a single work station in the main production line to the frame 10 and thus to the shell.
[0018] After assembly of the adapter elements 16 , 18 on the frame 10 additional functional components 22 —an overview of which is shown in FIG. 3 —are connected to the roof module. It is hereby a question of drive motors 24 for driving sliding roofs, corresponding rail systems 26 , in which the sliding roofs run, guide rails 28 and also sunshades 30 . The necessary functionality for movable design variants of the roof module is thus provided.
[0019] In the final assembly stage the planar elements, which close the roof module outwardly and together form a respective design-variant-specific cover part, are assembled on the structure present thus far. FIG. 4A shows a cover part 32 for a panoramic glass roof. The cover part 34 is divided into two in the region of the B pillar and comprises a front planar element 34 and a rear planar element 36 which are respectively formed transparently. In the region of the abutment 38 between the planar elements 34 and 36 , for example, the reinforcement shown in FIG. 2 can be carried out through the transverse bow 20 . An only partially transparent or opaque solid roof can also be produced through corresponding selection of the planar elements 34 , 36 in this way.
[0020] FIG. 4B shows a cover part 40 for a sliding and lifting roof that is also divided into two. The rear planar element 42 is thereby designed in the usual way as a sheet metal outer shell, the front planar element 43 contains the actual outward movement mechanism so that the sliding and lifting roof can be moved out in the direction of the arrow 44 .
[0021] FIG. 4C shows a cover part 46 for an outwardly extending sliding roof, wherein on the front adapter element 16 , which comprises the passage opening 16 a, a displaceable roof element 52 is arranged that can initially be moved out in the direction of the arrow 54 and then displaced in the direction of the arrow 56 towards the rear via a rear planar element which is hidden in the illustration shown.
[0022] All cover parts can—as shown in FIG. 4 A-C—be designed in two parts. It is also possible, however, to design them in one part.
[0023] The respective rear planar elements 36 , 42 of the three variants shown in FIG. 4 are arranged via the respective adapter element 18 in a fixed manner on the motor car roof. The planar elements can thereby be transparent or translucent and consist of an extensively free choice of materials from glass, plastic or sheet metal. The front planar element 43 , 52 can be movable and in particular be designed to open.
[0024] It is particularly advantageous to design the roof modules so that they can be introduced, preferably adhesively bonded, from above into a vehicle shell. This simplifies the assembly and reduces the required construction space so that the headroom for vehicle occupants is improved. In comparison with roof modules incorporated from below the water drainage into the wet area shell is also possible so that additional water discharge hoses can be omitted.
[0025] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
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A modular construction system for producing a plurality of design variants of a roof module for a motor car includes a plurality of design-variant-specific adapter elements and a plurality of design-variant-specific planar elements. Using at least one adapter element, at least one respective planar element can be connected to a frame, forming a roof opening, in particular of a motor car shell.
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CLAIM TO PRIORITY
[0001] This application claims the benefit of pending United States provisional patent application entitled “SIDE ENTRY CIRCUIT BREAKER” filed Feb. 19, 2008 and assigned Ser. No. 61/029,589, and also provisional patent application entitled “CIRCUIT BREAKER WITH DETACHABLE RECEPTACLE” filed Jul. 30, 2008 and assigned Ser. No. 61/084,719, both of which are incorporated by reference herein.
BACKGROUND OF THE DISCLOSURE
[0002] 1. Field of the Invention
[0003] The present invention is directed to circuit breakers for circuit protection and control of electrical distribution systems. It is suitable for application in low voltage alternating current electrical systems commonly employed in residential and commercial structures.
[0004] 2. Description of the Prior Art
[0005] Circuit breakers are often mounted in electrical enclosures, such as metering stacks. Referring to FIG. 1 , the metering enclosure 10 is of an exemplary type commonly used in multiple unit occupancy buildings. The enclosure 10 has a plurality of stacked electric meters 12 that are coupled to an electric power grid so that they can provide rate-metered electric power to each corresponding occupancy unit. In FIG. 1 , each meter is in turn wired to a downstream circuit breaker 14 , often through a metering socket assembly having a pair of male stabs that plug into female biased jaws incorporated into the circuit breaker (not shown). The circuit breaker 14 has a pair of load terminals, often of a terminal lug configuration. Each lug is wired to one or more load wires or cables 16 . Generally circuit breaker load terminals are configured at the top of the circuit breaker 12 , as shown in FIG. 1 .
[0006] FIG. 2 shows a prior art two-pole circuit breaker 20 that is sold by Siemens Energy & Automation, Inc. The circuit breaker 20 has a left load lug 22 that employs an allen screw 24 for crimped capture of a load cable. There is also a right lug 26 with corresponding allen screw 28 . Both lugs 22 , 24 are retained in a molded breaker housing 30 proximal the top side housing wall 32 . The front cover 34 includes windows 36 , 38 for access to the allen screws 24 , 28 .
[0007] Referring back to FIG. 1 , the load cables 16 are routed from the top of the circuit breaker 12 in a U-shaped bend and down in a meter enclosure gutter. Alternatively, the cables 16 are routed in an upwardly direction in an “S-bend”. The cables 16 thereafter exit the meter enclosure 10 , for further distribution to the building occupancy units. Cable thickness dictates the U-bend or S-bend radius necessary for routing them from the circuit breaker to the gutter. As shown in FIG. 1 , the cable 16 bend radius dictates minimum vertical spacing S between each meter 12 in the enclosure 10 . It is desirable to minimize the vertical spacing S to maximize the number of meters that are stackable in an enclosure cabinet. Elimination of the need to form U-bends or S-bends in the load cables 16 is a desirable objective. One previous solution to eliminate the need for U-bend or S-bend formation in load cables was fabrication of a circuit breaker having side-access lugs.
[0008] FIG. 3 is a schematic representation of a left side-access circuit breaker 40 previously sold under the MURRAY® brand model designation 200V. The subject prior art circuit breaker 40 had a left lug 42 with allen screw 44 and a corresponding right lug 46 with allen screw 48 . The circuit breaker housing 50 enabled left side access of load cables 16 along the left side wall 52 . Front cover 54 , along with upstanding internal walls 55 in the housing 50 captured and electrically isolated each respective breaker lug 42 , 46 . Windows 56 , 58 enabled access to the allen screws 44 , 46 for selective clamping of the load cables 16 .
[0009] Full isolation of each of the lugs by surrounding insulating walls 55 and cover 54 was in compliance with electrical code over surface spacing requirements. For example, if a cable lug were not surrounded by insulating material on all sides with exception of the cable insertion direction, it might be possible to have excess cable protruding through the lug in violation of over surface spacing requirements. As a result of the over surface requirement, a drawback of the prior art breaker design 40 is that the lugs were configured at the factory for only left side load cable access, or in one other variation top access similar to the prior art circuit breaker of FIG. 2 . If an electrical enclosure installation required right side cable routing rather than left side routing, the only practical recourse was to utilize a top-access circuit breaker.
[0010] It is desirable for electrical enclosure design an installation flexibility to eliminate the need for U-bend or S-bend cable clearances in applications that require left or right side cable gutter routing, or a combination of both in a single enclosure, while complying with electrical code over spacing requirements.
SUMMARY OF THE INVENTION
[0011] Accordingly, it is an object of the invention to configure a circuit breaker that eliminates the need to route cables with U-bends or S-bends and offers the flexibility of either left or right side cable routing, or both in any application, while complying with electrical code over spacing requirements.
[0012] Independent from the first object of the invention, it is an additional and separate object to provide additional cable routing flexibility to enable load cables to be inserted vertically into the circuit breaker lugs in a plane normal to and above the circuit breaker front cover in applications where it is desirable to route cables in a plane above the circuit breaker.
[0013] These and other objects are achieved by the circuit breaker of the present invention that enables selective side feed of load cables from either the left or right side or a combination of both. The circuit breaker of the present invention allows an enclosure designer to minimize wiring spacing within electrical enclosures by avoiding the need for complex cable bends, while complying with electrical code over surface spacing requirements.
[0014] One aspect of the present invention is directed to a circuit breaker having a housing defining a longitudinal axis, having left and right surfaces that are generally aligned with the longitudinal axis. The circuit breaker has an electrically non-conductive cavity commonly defined by the housing left and right surfaces, which is adapted for selective insertion and receipt of a power circuit conductor, such as a wire or cable, within either the left or right housing surface. The circuit breaker has a wiring connector that is retained within the cavity, adapted for retention of the power circuit conductor.
[0015] Another aspect of the present invention is directed to a circuit breaker having a housing defining a longitudinal axis, having left and right surfaces that are generally aligned with the longitudinal axis. An electrically non-conductive cavity is commonly defined by the housing left and right surfaces, that is adapted for selective insertion and receipt of a power circuit conductor, such as for example a wire or cable, within either the left or right housing surface. A wiring connector is retained within the cavity, adapted for retention of a power circuit conductor. The circuit breaker has an inspection window defined by the housing, such as in the cover. The window is oriented for visual inspection of at least a portion of the wiring connector and any power circuit conductor that is retained by the connector.
[0016] Yet another aspect of the present invention is directed to a circuit breaker having a housing defining a first longitudinal axis and a receptacle portion having left and right surfaces that are generally aligned with a second longitudinal axis, wherein the respective longitudinal axes are aligned generally normal to each other. An electrically non-conductive cavity is commonly defined by the receptacle left and right surfaces, that is adapted for selective insertion and receipt of a power circuit conductor within either the left or right surface. A wiring connector is retained within the cavity, adapted for retention of a power circuit conductor.
[0017] There is also another aspect of the present invention that is directed to a circuit breaker having a housing defining a first longitudinal axis and a receptacle having left and right surfaces that are generally aligned with a second longitudinal axis. The receptacle is selectively attachable to the housing in a first orientation with the respective longitudinal axes aligned generally in parallel and in a second orientation with the respective longitudinal axes aligned generally normal to each other. An electrically non-conductive cavity is commonly defined by the receptacle left and right surfaces, that is adapted for selective insertion and receipt of a power circuit conductor, such as a cable or wire, within either the left or right surface. The circuit breaker has a wiring connector that is retained within the cavity, adapted for retention of a power circuit conductor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which:
[0019] FIG. 1 is a schematic elevational drawing of a prior art metering stack electrical enclosure;
[0020] FIG. 2 is a perspective view of a prior art top feed-type circuit breaker;
[0021] FIG. 3 is a schematic partial front elevational view of a prior art left side feed circuit breaker;
[0022] FIG. 4 is a top right side perspective view of an embodiment of a circuit breaker of the present invention;
[0023] FIG. 5 is a top left side perspective view of the circuit breaker of FIG. 4 ;
[0024] FIG. 6 is a bottom left perspective view of the circuit breaker of FIG. 4 ;
[0025] FIG. 7 is a partial front elevational view of the circuit breaker of FIG. 4 ;
[0026] FIGS. 8A and 8B are fragmentary front plan views of a visualization window embodiment of the circuit breaker of the present invention, showing cable retention through a visualization window feature of the present invention;
[0027] FIG. 9 is a schematic view of an electrical enclosure showing application of an embodiment of a circuit breaker of the present invention configured for left side connection to power cables routed in a left cable gutter;
[0028] FIG. 10 is a schematic view similar to FIG. 9 , showing right side connection to power cables routed in a right cable gutter;
[0029] FIG. 11 is a perspective exploded view of an another embodiment of the circuit breaker of the present invention having a detachable lug receptacle oriented parallel to the circuit breaker longitudinal axis in a horizontal position;
[0030] FIG. 12 is a perspective exploded view similar to that of FIG. 11 , having a detachable lug receptacle oriented normal to the circuit breaker longitudinal axis in a vertical position;
[0031] FIG. 13 is a perspective view of the receptacle housing of FIG. 11 ;
[0032] FIG. 14 is a perspective view of the conductor lugs retained in the receptacle housing of FIG. 13 when oriented in a horizontal position;
[0033] FIG. 15 is a perspective view of the receptacle housing of FIG. 12 ;
[0034] FIG. 16 is a perspective view of the conductor lugs retained in the receptacle housing of FIG. 15 when oriented in a vertical position; and
[0035] FIG. 17 is a perspective view of the receptacle housing of the present invention corresponding to the embodiment of FIGS. 11 and 12 , showing position of knock-outs for selective orientation and connection of the housing to the circuit breaker.
[0036] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
[0037] After considering the following description, those skilled in the art will clearly realize that the teachings of my invention can be readily utilized in making and using the circuit breaker of the present invention.
[0038] FIGS. 1-3 , depicting prior art electrical enclosures and circuit breaker designs have been described in the Background of the Disclosure section, above. The prior art circuit breakers did not offer the design application flexibility to enable left or right side wiring connection or a combination of both. Lugs were permanently oriented to enable only left or top side wiring, among other reasons to comply with electrical code over surface spacing requirements, so that wire or cable conductors were maintained at a minimum distance from other components within the electrical enclosure.
[0039] An embodiment of the circuit breakers of the present invention that enables selective left or right or combination of both side wiring is shown in FIGS. 4-6 . Referring generally to those figures, circuit breaker 60 has a wiring connector left lug 62 of conventional design, with an allen screw 64 for selective retention of an electrical conductor, such as a cable or wire 16 . Other types of wiring connectors known in the art can be substituted for lug 62 . The circuit breaker 60 is a two pole or phase device and therefore has a right lug 66 with allen screw 68 for selective retention of another phase wire 16 . The present invention can be utilized in single-pole or multi-pole applications.
[0040] The circuit breaker 60 has a non-conductive breaker housing including a base portion 70 that defines a left side wall 72 , a right side wall 74 and a top wall 76 . The breaker housing 70 defines respective non-conductive left and right lug channel cavities 78 , 80 that pass through the right 74 and left 72 side walls. The left lug 62 is captured in the left channel 78 and the right lug 66 is correspondingly captured in the right channel 80 . The electrically isolated, non-conductive channel cavities 78 , 80 isolate the respective electrical phases from each other and from other components in the vicinity 30 of the breaker lugs 62 , 66 . An electrical cable or other conductor for each phase may be passed through the respective channel cavity 78 , 80 from either the left or right side or a combination of both, for capture by the respective lug 62 , 66 . Thereupon the conductor is restrained in the lug by tightening of the appropriate lug screw 64 , 68 through the housing front cover 82 respective window 84 , 86 .
[0041] Referring now to FIGS. 7 , 8 A and 8 B, in an embodiment of the present invention the lug windows 84 , 86 provide for visual inspection of each lug 62 , 66 and their respective lug faces (e.g., 62 A in FIGS. 8A and 8B ). The windows 84 , 86 allow an installer to see wire extension 16 A beyond the lug faces 62 A as a way to prevent excess extension of wire into the enclosure interior. This feature is helpful to assure compliance with over surface spacing requirements in electrical codes, such as UL 489 . Section 6.6.6.
[0042] The housing front cover 82 also provides access to the circuit breaker toggle 83 that selectively opens, closes and resets circuit breaker contacts (not shown). The circuit breaker contacts, internal electrical circuit protection and control apparatus (e.g., toggle mechanism and trip unit) and internal bussing are of any known design and not shown for brevity. The term “housing” is used herein to describe the circuit breaker encasement structure that as shown in this embodiment includes a housing base 70 and housing front cover 82 . It is possible that the base and cover (or any portions thereof, may be constructed as a unified molding.
[0043] Referring to FIG. 6 , the breaker housing bottom 87 retains a pair of female biased jaws 88 , 89 for connection to bus stabs in the electrical enclosure (not shown) and are of known design. Electrical current flows through the jaws and a respective line bus (not shown) for each phase, through the respective closed circuit breaker contacts and in turn to the respective load busses connected to each of the respective left and right lugs 62 , 66 .
[0044] FIGS. 9 and 10 show application of the circuit breaker 60 of the present invention in respective left gutter and right gutter configurations. In FIG. 9 the load cables 16 are inserted in the left side wall 72 of the breaker. Conversely in FIG. 10 the power conductor cables 16 are inserted in the right side wall 72 of the breaker. In both figures, the ability to insert power cables 16 by a simple L-bend rather than a U-bend shown in a FIG. 1 prior art configuration enables reduction of the vertical spacing S between the ganged meters 12 .
[0045] FIGS. 11-17 show another embodiment of circuit breaker 90 of the present invention in which the left and right load lugs 92 , 96 can be oriented in a horizontal position, generally aligned with the longitudinal axis of the breaker or in a vertical position generally normal to the breaker longitudinal axis. The vertical position enables routing of cables above the circuit breaker top cover. While the specific embodiment in FIGS. 11-17 shows a circuit breaker with convertible lug orientation to either horizontal or vertical positions, one skilled in the art can appreciate that a circuit breaker can be constructed with the lugs oriented only in a fixed, vertical position.
[0046] Referring to FIGS. 11 and 14 , the circuit breaker 90 has many features similar to the circuit breaker 60 of FIGS. 4-10 , including left lug 92 with allen screw 94 , the right lug 96 with allen screw 98 , breaker housing base 100 and front cover 101 . The housing has a front side 102 that retains a pair of load bus tabs 104 , 106 that in this exemplary embodiment have threaded bores for receipt of load bus fasteners 108 , 110 . The load bus tabs 104 , 106 are oriented in load bus housing channels 112 , 114 .
[0047] The circuit breaker 90 has a detachable lug receptacle 116 that is formed with lug receptacle base 118 and lug receptacle cover 120 . As with the circuit breaker housing 102 , the receptacle base 118 and cover 120 may be constructed as separate components, as shown, or integrated in whole or in part. As one skilled in the art can appreciate, all or portions of the housing 110 and receptacle 116 can be formed in a unitary construction, such as by way of example orienting the lugs permanently in a vertical position during manufacture.
[0048] The lug receptacle 116 may be transposed from a horizontal orientation ( FIG. 12 ) or a vertical orientation ( FIG. 13 ) during factory assembly of the breaker 90 or during field installation. In this manner, a single receptacle design may be used in two different applications, thus eliminating the need to manufacture and inventory separate products for each application.
[0049] The receptacle 116 forms a left lug channel 122 and a right lug channel 124 , as was described with respect to the circuit breaker 60 embodiment, above. Left and right lug windows 126 , 128 are shown, having the construction and features of the circuit breaker 60 lug windows 84 , 86 .
[0050] FIGS. 13 and 14 show in further detail the receptacle 116 components as configured for horizontal lug orientation. The receptacle base 118 is constructed with load bus attachment openings 129 , 130 for communication with the housing channels 112 , 114 and defines holes 132 , 134 for passage of the load bus fasteners 108 , 110 previously described. Left and right receptacle busses 136 , 138 are connected to the respective left 92 and right 96 lugs by a U-shaped tongue in each bus mating with a slot in each lug in a manner known to those skilled in the art. Left and right horizontal threaded blocks 140 , 142 are constructed as part of each of the respective receptacle busses 136 , 138 for connection to load bus tabs 104 , 106 by way of the fasteners 108 , 110 . Any form of fastener known to those skilled in the art suitable for electrical conductor connectivity in circuit breaker applications may be utilized as a substitute for the threaded fasteners 108 , 110 .
[0051] FIGS. 15 and 16 show in further detail the receptacle 116 components as configured for vertical lug orientation. The receptacle base 118 is constructed with load bus attachment openings 144 , 146 for communication with the housing channels 112 , 114 and defines holes 148 , 150 for passage of the load bus fasteners 108 , 110 previously described. Left and right receptacle busses 136 , 138 are the same as those utilized in the horizontal lug orientation application and are connected to the respective left 92 and right 96 lugs by a U-shaped tongue in each bus mating with a slot in each lug in a manner known to those skilled in the art. Left and right horizontal threaded blocks 154 , 156 are disposed on opposite sides of the blocks 140 , 142 that were utilized for the horizontal lug orientation configuration. The threaded blocks 154 , 156 are constructed as part of each of the respective receptacle busses 136 , 138 for connection to load bus tabs 104 , 106 by way of the fasteners 108 , 110 .
[0052] FIG. 17 shows an embodiment of the receptacle base 118 wherein all of the load bus tab 104 , 106 attachment openings and holes for corresponding fasteners 108 , 110 are formed as knockouts 129 K, 130 K, 132 K, 134 K for horizontal lug orientation. Similar knockouts for vertical lug orientation are shown as 144 K, 146 K, 148 K and 150 K. In this manner, a field installer can determine whether an application calls for horizontal or vertical lug orientation and thereafter remove the appropriate set of knockouts for the desired application.
[0053] As can be appreciated by those skilled in the art, the circuit breaker of the present invention affords a designer and installer a flexible application product that can be adapted to meet varying wire routing design constraints.
[0054] Although various exemplary embodiments which incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. Accordingly it is intended that the scope of the present be defined by the accompanying claims given their broadest interpretation allowable by law, rather than by the exemplary embodiments described above that are intended to help those skilled in the art understand how to make and use the subject invention.
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A circuit breaker enables selective left, right or a combination of both side connection to a power conductor, such as a cable or wire. Side connection eliminates the need for large radius U-bends of the power conductor that is normally required when using top connection circuit breakers. An electrically non-conductive cavity commonly defined by left and right sides of the circuit breaker housing receives the power conductor in a connector such as a lug. The circuit breaker may have a visualization window oriented to observe whether excessive cable is projecting out of the lug, so as to confirm compliance with electrical code over surface spacing requirements. In some embodiments, the circuit breaker lugs are vertically oriented above its front cover surface in a receptacle portion of the housing. The receptacle may be constructed for selective lug orientation in horizontal or vertical positions by the installer.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application is U.S. National Phase Application of International Application No. PCT/IB2013/055387, filed Jul. 1, 2013, the entire content of which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
The subject matter relates to the removal of particulate matter from gases and more particularly, to a device for the removal of particulate matter contained in the exhaust of internal combustion engines without increasing the resistance to the flow of exhaust gases.
BACKGROUND
The exhaust gases coming out of the internal combustion engines contain particulate matter. This particulate matter in the environment is a well recognized health hazard of serious proportion. The finer the size of the particulate matter, the greater the chance it will remain suspended in air and, therefore, the more harmful are its impacts on both health and environment. The fine particulate matter generated by combustion of fuel carries with it substances that are known allergens, carcinogens and mutagenic agents. This fine particulate matter, because of its small size, travels deep into the respiratory tree, very often reaching the alveolar level, where it begins to cause serious diseases. Bronchitis, asthma, lung abbess and cancer have all, in a major part, been attributed to high levels of inhalable particulate matter in the atmosphere.
The consequences of fine particulate matter becomes much more severe because of its nature of not settling down and remaining in circulation in the air; it is often carried to high altitudes by convection currents. At cloud formation heights, this fine particulate matter acts as nuclei for water vapor condensation, forming clouds. The clouds so formed are heavier than the naturally formed clouds and are not sufficiently carried by the prevailing winds. Such clouds result in skewed distribution of rainfall such that some areas are subjected to very heavy and damaging downpour whereas others suffer drought like conditions.
Various methods have been attempted in the past to overcome the problem of particulate matter prevalent in the flowing gases, i.e. either in the exhaust stream of internal combustion engines or in the effluent gases in various industrial processes or furnaces.
One of the methods employed in the past enables internal combustion engines to use an array of sensors along with a microprocessor to ensure that the correct air-fuel mixture is maintained at all times and through all load conditions so as to get better combustion and thus, produce less particulate matter. The pre-treatment of fuel through temperature and chemical additives is another method that has been employed to achieve efficient combustion and hence, reduced particulate matter production.
The abovementioned methods pertain to the pre-ignition stage in the internal combustion engine. Once ignition occurs, all the exhaust matter needs to be pushed out of the cylinder so that the cylinder is ready and empty to accept the next air-fuel charge. The exhaust material is expelled out of the cylinder with a lot of noise and to reduce the noise, sound reducers or mufflers are put in line of flow of exhaust matter.
The catalytic converter, which is intended to convert harmful gases to less harmful ones, is also placed in line of flow of the exhaust matter.
It is further studied that any attempt to place a filter in line with the flow of exhaust increases the resistance to the flow of exhaust or causes backpressure in the flow. This prevents the engine cylinder from fully voiding itself of the exhaust gases generated by the ignition of previous air-fuel charge and is unable to perform an efficient combustion by not being able to accept the next pocket of air-fuel charge. Also, the increased resistance to flow of exhaust gases results in the loading of the engine i.e., the engine has to do more work in order to vent the exhaust material and this has a negative impact on fuel consumption. Further, the in-line filters get clogged with the particulate matter which need to be unclogged using some regenerative technology. During the process of regeneration, the particulate matter is expelled out and this particulate matter, being very fine in nature, is much more harmful.
Settling and momentum separators are also being used for removal of particulate matter from flowing gases wherein particles are collected by gravity and by their inertia, due to a sudden change in the direction of exhaust gases. Momentum separators are not effective because of the low mass of the particles involved.
There is another method known in the art for removing particulate matter from the flowing gases; namely cyclone or vortex separators which operate by incorporating centrifugal, gravitational, and inertial forces to remove particles suspended in air or gas. These types of separators use cyclonic action to separate particulates from a gas stream.
The most common type of cyclone separator used in industry is reverse flow type, wherein the gas enters through a tangential inlet at the top of the cyclone body, shaped to create a confined vortex gas flow and the clean gas exits through a central pipe.
Some of the major disadvantages with cyclone separators are that they have low efficiencies (particularly for small particles) and are unable to process “sticky” materials.
Some of the other methods used in the past include “Electrostatic Separators” and “Wet Collectors or Scrubbers”.
In view of foregoing, it is quite evident that all the above mentioned methods presently employed for removing particulate matter from flowing stream of gas are unable to separate the particulate laden gases in an effective and desired manner. Thus, it is a subject of immediate requirement to efficiently remove the particulate matter from the stream of flowing gases, especially the ones accompanying the exhaust of internal combustion engines and thereby reduce the harmful effects of particulate matter emitted in the environment.
SUMMARY
It is an object of the present invention to remove particulate matter from the exhaust of internal combustion engines.
It is a further object of the present invention to trap the particulate matter present in the exhaust gases in an enclosed trap.
It is yet another object of the present invention to remove the particulate matter without increasing the resistance to the flow of exhaust gases, thereby reducing the work done by the engine in exhausting the gases.
It is yet another object of the present invention to minimize the capital cost and maintenance requirements by not using any moving part in the system.
The present subject matter comprises a device for removing particulate matter from the exhaust gases of internal combustion engines. The device includes a hollow chamber ( 3 ) having a proximal end ( 11 ), a distal end ( 10 ) and an intermediate portion, a means for tangentially introducing the exhaust gas at the proximal end ( 11 ) of the hollow chamber ( 3 ), a trap ( 6 ) for trapping the particulate matter in the exhaust gas and a means for drawing the portion of the exhaust gas containing the particulate matter from the trap ( 6 ) to a low pressure area in the hollow chamber ( 3 ). The intermediate portion of the hollow chamber ( 3 ) draws the particulate matter and a portion of the exhaust gas containing the particulate matter into the trap ( 6 ).
In a preferred embodiment of the present subject matter, the means for introducing the exhaust gas into the hollow chamber ( 3 ) in a tangential direction comprises at least one duct ( 1 , 2 ) provided at the proximal end ( 11 ) of the hollow chamber ( 3 ).
In a preferred embodiment of the present subject matter, a plurality of ducts ( 1 , 2 ) is provided at the proximal end ( 11 ) of the hollow chamber ( 3 ).
In a preferred embodiment of the present subject matter, the intermediate portion of the hollow chamber ( 3 ) comprises a plurality of ports ( 4 ) for drawing the particulate matter and a portion of the exhaust gas with the particulate matter into the trap ( 6 ).
In a preferred embodiment of the present subject matter, the intermediate portion of the hollow chamber ( 3 ) comprises a plurality of radial projections ( 5 ) for drawing off the particulate matter and a portion of the exhaust gas with the particulate matter into the trap ( 6 ).
In a preferred embodiment of the present subject matter, the radial projections ( 5 ) have an axial width and a plurality of ports. In a preferred embodiment of the present subject matter, the trap ( 6 ) is provided with a high temperature resistant porous material (not shown for the sake of simplification).
In a preferred embodiment of the present subject matter, the trap ( 6 ) is formed by a cover ( 7 ) enclosing the intermediate portion of the hollow chamber ( 3 ) such that there is space between the hollow chamber and the outer cover to contain charged or uncharged porous entrapping material.
In a preferred embodiment of the present subject matter, the distal end ( 10 ) of the hollow chamber ( 3 ) is open for emitting the exhaust gases.
In a preferred embodiment of the present subject matter, the means for drawing the portion of the exhaust gas with the particulate matter from the trap ( 6 ) to the low pressure area in the hollow chamber ( 3 ) comprises at least one duct ( 8 , 12 ).
In a preferred embodiment of the present subject matter, a plurality of ducts ( 8 , 12 ) coincide with each other for drawing the portion of the exhaust gas with the particulate matter from the trap ( 6 ) to the low pressure area in the hollow chamber ( 3 ).
BRIEF DESCRIPTION OF DRAWINGS
A further understanding of the present invention can be obtained by reference to a preferred embodiment set forth in the illustrations of the accompanying drawings. The drawings are not intended to limit the scope of this invention, which is set forth with particularity in the claims as appended or as subsequently amended, but merely to clarify and exemplify the subject matter.
For a more complete understanding of the present invention, reference is now made to the following drawings in which:
FIG. 1 is a three dimensional line diagram showing the assembly of a device for removal of particulate matter from the exhaust of internal combustion engines in accordance with an embodiment of the present subject matter.
FIG. 2 is a schematic illustration of the device depicting the operation of the device in accordance with an embodiment of the present subject matter.
FIG. 3 is an exploded view of the device in accordance with a preferred embodiment of the present subject matter.
DETAILED DESCRIPTION
The following presents a detailed description of a preferred embodiment (as well as some alternative embodiments) of the present invention with reference to the accompanying drawings.
The embodiments of the present subject matter are described in detail with reference to the accompanying drawings. However, the present subject matter is not limited to these embodiments which are only provided to explain more clearly the present subject matter to the ordinarily skilled in the art of the present disclosure. In the accompanying drawings, like reference numerals are used to indicate like components.
According to an embodiment of the present subject matter, the assembly of a device ( 100 ) used for the removal of particulate matter from the exhaust of internal combustion engines is shown in FIG. 1 . The FIG. 1 is shown for example only and by no way limits the scope of the subject matter. The device ( 100 ) is manufactured from a plurality of components. The components of the device ( 100 ) include, but are not limited to, a plurality of ducts ( 1 , 2 , 8 , 12 ), a hollow chamber ( 3 ), a trap ( 6 ), a cover ( 7 ) etc. The hollow chamber ( 3 ) is provided with at least one duct ( 1 , 2 ) in such a manner that the exhaust gases coming from the internal combustion engine enter into the hollow chamber ( 3 ) in a tangential direction. In an embodiment of the present subject matter, the hollow chamber ( 3 ) is provided with a plurality of ducts i.e. a first duct ( 1 ) and a second duct ( 2 ). The hollow chamber ( 3 ) is open at the distal end ( 10 ) and is closed at the proximal end ( 11 ). The proximal end ( 11 ) of the hollow chamber ( 3 ) is provided with a port ( 9 ), through which a fourth duct ( 12 ) emerges and coincides with a third duct ( 8 ) provided on the cover ( 7 ).
The subject matter described above can be embodied in many ways as would be obvious and known to a person skilled in the art. For example, the ducts ( 1 , 2 , 8 & 12 ) described above are embodied as having a circular cross section. The shape and size of these ducts can be varied to any desired shape or size as is obvious to a person skilled in the art. Similarly, the number of ducts ( 1 , 2 , 8 & 12 ) is not limited to what has been described in the above embodiment. In different embodiments, the number of ducts can also be varied as desired.
FIGS. 2 and 3 depict a schematic representation and an exploded view of the device ( 100 ) of FIG. 1 . As shown in the figures, the intermediate portion of the hollow chamber ( 3 ) is provided with plurality of ports ( 4 ) located on the surface of the hollow chamber which has radial projections ( 5 ) indented at specific intervals along the length of the hollow chamber ( 3 ). The intermediate portion of the hollow chamber ( 3 ) is surrounded by the cover ( 7 ), enclosing the hollow chamber ( 3 ). The space between the cover ( 7 ) and hollow chamber ( 3 ) is filled with high temperature resistant porous material forming the trap ( 6 ) for the particulate matter.
The radial projections ( 5 ) are a plurality of protrusions running along the wall of the hollow chamber ( 3 ). These protrusions are in the radial direction of the hollow chamber ( 3 ) and have a radial depth and their width is in the axial direction of the hollow chamber ( 3 ). As in the case of the balance surface of the intermediate portion of the hollow chamber ( 3 ), these protrusions also have multiple ports ( 4 ) on their surface to facilitate the movement of the particulate matter into the trap ( 6 ); the space formed between the hollow chamber ( 3 ) and cover ( 7 ) and filled with high temperature resistant porous material.
When the exhaust gases are tangentially introduced into the hollow chamber ( 3 ), these gases, along with the particulate matter present in them, spin at very high speed, experiencing a centrifugal force in the radial direction. Under this force, the particulate matter travels radially outwards while travelling axially along the hollow chamber ( 3 ). In addition to some particulate matter flowing out of the ports provided in the plane surface of the hollow chamber ( 3 ), the radial projections ( 5 ) vastly enhance the exit of the particulate matter through the ports provided on them as the particulate matter which enters these radial projections ( 5 ) is unable to flow backwards into the hollow chamber ( 3 ) because of the direction of the centrifugal force. The radial projections ( 5 ) act as a centrifugal trap for the particulate matter before it flows into the main trap ( 6 ) where it gets collected.
The cover ( 7 ) is provided with the third duct ( 8 ) that, in combination with the fourth duct ( 12 ), connects the trap ( 6 ), having higher pressure, to the low pressure area at the center of the proximal end ( 11 ) of the hollow chamber ( 3 ). The exhaust gases entering the hollow chamber ( 3 ) through the first and second ducts ( 1 & 2 ) create a cyclonic flow with high rotational speed and pass through the length of the hollow chamber ( 3 ) towards the distal end ( 10 ) and get emitted. As the exhaust gases flow through the intermediate portion of the hollow chamber ( 3 ), the particulate matter present in them is forced out of the hollow chamber ( 3 ) through the multiple ports ( 4 ) into the outer cover ( 7 ) and gets entrapped in a high temperature resistant porous material forming the trap ( 6 ).
Referring FIG. 2 , the operation of the device to remove the particulate matter from the exhaust gases of the internal combustion engine is explained in accordance with an embodiment of the present subject matter. The exhaust gases coming from the engine are allowed to enter into the hollow chamber ( 3 ) through ducts ( 1 & 2 ) in a tangential direction. The hollow chamber ( 3 ) is closed at the proximal end, such that a high rotational motion of the exhaust gases is set up. The distal end ( 10 ) of hollow chamber ( 3 ) is open for releasing the exhaust gases, which are free of the particulate matter. This high rotational motion of the exhaust gases causes a centrifugal force to act on the particulate matter present in the exhaust gases and it is under the influence of this centrifugal force that the particulate matter is forced to move radially away into the trap ( 6 ) through the ports ( 4 ) in the intermediate portion of the hollow chamber ( 3 ).
The intermediate portion of the hollow chamber ( 3 ) is provided with a plurality of ports ( 4 ), which allow the particulate laden gas to enter into the trap ( 6 ) enclosed by the cover ( 7 ). The entry of particulate laden gas into the trap ( 6 ) raises the pressure in the enclosed trap ( 6 ). The hollow chamber ( 3 ) is also provided with radial projections ( 5 ) having axial width. The radial projections ( 5 ) also possess ports for the radial flow of particulate laden gases into the trap ( 6 ). The purpose of these radial projections ( 5 ) is to act as an additional centrifugal trap such that the particulate matter present in the rotating particulate laden gases that enter the radial projections ( 5 ) is unable to fall back towards the out-going particulate free exhaust gases, due to the opposing centrifugal force of the rotating mass of gases.
In accordance with a preferred embodiment, the radial projections ( 5 ) are provided with axial width in the form of a helix. However, any other configuration of the radial projections ( 5 ) can be embodied as is obvious and known to a person skilled in the art.
The axial surface of hollow chamber ( 3 ) having ports ( 4 ) and radial projections ( 5 ) with axial width that allows the particulate laden gas containing particulate matter to enter into an enclosed trap ( 6 ) further comprises of a fine mesh of high temperature resistant porous material on which the particulate matter gets deposited or the particulate matter sticks to the porous material. The high temperature resistant porous material described above can have as many embodiments as obvious and known to a person skilled in the art.
In accordance with a preferred embodiment of the present subject matter, the high temperature resistant porous material is a glass wool or glass wool mixed with metal wool.
In accordance with another embodiment(s) of the present subject matter, the high temperature resistant porous material is a porous ceramic or metal lattice structure, multi layered fine mesh net made of metal or ceramic, porous earthen ware lattice structure, electrically charged porous material and any other porous material used for similar function or a combination thereof. In accordance with a preferred embodiment of the present subject matter, the cover ( 7 ) encloses the trap ( 6 ) which is formed by placing the porous material over the ports ( 4 ) and the radial projections ( 5 ) present on the intermediate portion of the hollow chamber ( 3 ).
Further, to assist the flow of particulate matter into the trap ( 6 ), a pressure gradient is maintained in the trap ( 6 ), for which the cover ( 7 ) is provided with a duct ( 8 ) that connects the trap ( 6 ) having higher pressure to the low pressure area of the rotating gases in the hollow chamber ( 3 ) through the proximal end ( 11 ) of the hollow chamber ( 3 ) for which a suitable port ( 9 ) is provided at the proximal end of the hollow chamber ( 3 ).
In accordance with a preferred embodiment of the present subject matter, any particulate matter that is not trapped in the enclosed trap ( 6 ), i.e. does not get stuck to the porous material ( 6 ), is sent back to the centre of rotating exhaust gases at the proximal end ( 11 ) of the hollow chamber ( 3 ) through the duct ( 8 ) on the cover ( 7 ) of the trap ( 6 ) and a port ( 9 ) at the proximal end of the hollow chamber ( 3 ).
Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the invention, will become apparent to persons skilled in the art upon reference to the description of the invention. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present invention as defined.
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A device to trap and remove particulate matter from exhaust of internal combustion engines, without increasing resistance to the flow of engine exhaust is disclosed herein. The system is provided with a single or a plurality of ducts ( 1 & 2 ) through which exhaust gases enter tangentially into a hollow chamber ( 3 ), causing the gases to spin at high speeds. The spinning gases generate centrifugal force resulting in separation of particulate matter from the exhaust gases. The hollow chamber ( 3 ) contains ports ( 4 ) and radial projections ( 5 ) on its axial surface to allow the separated particulate matter to enter into a trap ( 6 ). The particulate matter entering the trap ( 6 ) gets stuck to a fine mesh of high temperature resistant porous material that may or may not be electrically charged. The trap ( 6 ) is enclosed in a cover ( 7 ) that encases the fine mesh which surrounds the ports ( 4 ) and radial projections ( 5 ). The cover ( 7 ) has a single or plurality of ducts ( 8 ) connecting the trap ( 6 ) to the low pressure area of the rotating gases in the hollow chamber ( 3 ) through the port ( 9 ) provided at the proximal end of the hollow chamber ( 3 ).
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BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention relates to an improved process for producing carbon fibers (hereinafter including graphite fibers also) which is excellent in operational stability, and more particularly to a process for producing carbon fibers which comprises thermally stabilizing and carbonizing acrylic fibers (including precursor fibers in filament form or in tow form) containing a predetermined amount of a straight chain silicone substance and a specific chemical substance, whereby high quality carbon fibers (carbon fiber filaments or tows) can be obtained and the operational stability in the step of heat treatment can be heightened.
B. Discussion of the Prior Art
It is already known that carbon fibers can be obtained by thermally stabilizing acrylic fibers in an oxidizing atmosphere at 200°-300° C., and then carbonizing the thus thermally stabilized fibers in a non-oxidizing atmosphere. However, what should be noted here is that the thermal stabilization reaction (oxidizing reaction) of acrylic fibers is an exothermal reaction, so that if the fibers are heated rapidly, local accumulation of heat takes place which is liable to cause an uneven reaction. Consequently, the fibers will fuse together or become brittle in the thermal stabilization step, and it is difficult to obtain high quality carbon fibers. Of course, various attempts have been made to remedy such technical defects. Such attempts include, for example, a method wherein the thermal stabilization is carried out at low temperatures for a long time, and a method wherein precursor fibers are impregnated with or caused to contain an organic silicone substance and then thermally stabilized, as described in Japanese Patent Laid-Open (Kokai) Application No. 117724/1974. However, in fact, these methods still involve unsolved problems. Namely, when the particular silicone substance as mentioned above is employed, the fusion or agglutination of acrylic fibers can be reduced to some extent, but on the other hand, owing to the water repellency of the silicone substance used, the acrylic fibers given such a substance tends to generate static electricity. When static electricity is generated, serious troubles such as fiber entanglement upon drawing out the fibers, winding of fibers around rollers or guides in the steps of thermal stabilization and carbonization, generation of fluff, etc. are caused and make the operation extremely unstable. To avoid such troubles, attempts were made to give the fibers antistatic spinning oils (anionic surface-active agents such as salts of higher fatty acids, higher alkyl sulfates, etc; cationic surface-active agents such as higher alkyl amine salts, etc.; nonionic surface-active agents such as condensation products of higher alkyl fatty acids with allyl alcohol or glycol) but when a usual spinning oil is used, it turns into a tar-like substance in the course of the thermal stabilization step, and a large amount of the heat-decomposed substance remains on the surface of the fibers. Therefore, the phenomenon of fiber fusion or agglutination occurs again and disadvantages such as fiber breakage, etc. are caused. Among others, when an acrylic fiber tow produced by wet-spinning is used as the starting material, the form of the tow is not only remarkably disordered by the repulsive power among single fibers owing to static electricity, but also aggulutination or fusion by the tar-like substance is frequently caused, and it has been difficult to obtain satisfactory carbon fibers.
SUMMARY OF THE INVENTION
Under such circumstances, we researched intensively to correct the above-mentioned defects and to obtain carbon fibers of high quality. As a result, we have found that, by introducing into acrylic fibers, a specific silicone oil and a substance which has an ability for preventing electric charge and which produces no substantial pitch- or tar-like substance, and then thermally stabilizing the fibers, it is possible to obviate all such troubles as fluffiness, spreading, filament breakage, etc. of the precursor fibers, and at the same time, it is possible to markedly heighten the operational stability in the production of carbon fibers. The present invention is based on this discovery.
Therefore, the main object of the present invention is to propose an improved process for producing carbon fibers having excellent physical properties.
Another object of the present invention is to eliminate the above-mentioned troubles such as fluffiness, spreading, filament breakage, etc. and to produce carbon fibers free from agglutination or fusion and having high strength and high modulus of elasticity by a heat treatment in a short time.
Other objects of the present invention will become apparent from the concrete explanation of the invention which will be described hereinafter.
Such objects of the present invention are attained by thermally stabilizing and carbonizing or further graphitizing acrylic fibers containing 0.1-5 weight %, based on the weight of the fibers, of a straight chain silicone substance (hereinafter referred to as silicone oil) and further containing 0.1-5 weight %, based on the weight of the fibers, of a chemical substance (hereinafter referred to as specific oil) which is selected from glycerine, polyethylene glycol, polypropylene glycol, alkyl derivatives thereof, mixtures or compounds of two or more of these substances, and which generates only a residue less than 5 weight % under the action of heat at 240° C. for one hour.
DETAILED DESCRIPTION OF THE INVENTION
By introducing two kinds of the specific treating substances into the structure of acrylic fibers (by fixing them on the surface of the fibers and/or by causing them to be contained in the fibers), it has become possible to suppress the generation of static electricity of the fibers and to give suitable bundling properties to the fibers, thereby preventing the generation of fluff in the thermal stabilization step and the winding of the fibers around the guides and rollers, and to markedly suppress the agglutination or fusion among the fibers, thereby preventing the generation of fluff and the winding of the fibers around the rollers and guides in the subsequent carbonizing step. These are outstanding characteristics of the present invention. In other words, the technical effects peculiar to the present invention are produced by the synergetic effect of two kinds of the specific treating substances. If one of said substances is not present, the objects of the present invention cannot be attained. Particularly in the case of tows of acrylic fibers, the synergetic effect is remarkable. Namely in respect to precursor fibers in tow form, the fibers after spinning are once packed in boxes or wound on spools, and then subjected to thermal stabilization, followed by the carbonization step. Upon such packing of tows into boxes, winding of them on spools or taking them out of these, the tows generate no substantial static electricity because of the treatment of two kinds of the specific substances of the present invention. Therefore, the handling of the tows becomes easier, and finally there is shown the merit of producing carbon fibers free from agglutination or fusion and having excellent physical properties.
The acrylic fibers used in the present invention are those produced from acrylonitrile homopolymers or acrylonitrile copolymers containing combined therewith at least 85 mol % acrylonitrile, preferably more than 90 mol %. As the copolymerization components, there can be mentioned known, unsaturated vinyl compounds copolymerizable with acrylonitrile, such as allyl alcohol, oxypropioacrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, itaconic acid, methyl acrylate, methyl methacrylate, acrylamide, N-methylolacrylamide, etc. Such acrylonitrile homopolymers or acrylonitrile copolymers are generally produced in a known polymerization system, such as solution polymerization system, bulk polymerization system, emulsion polymerization system, or suspension polymerization system. As the solvents used upon producing acrylic fibers from these polymers, there are used organic solvents such as dimethylformamide, dimethylacetamide, dimethyl sulfoxide, etc.; inorganic solvents such as nitric acid, aqueous solutions of zinc chloride, aqueous solutions of thiocyanates, etc. The polymers are spun into fibers in the usual way.
The silicone oils used in the present invention are those shown by the following formula, and are liquids having a viscosity (at room temperature) of 50-1,000,000 centipoises, preferably 100-10,000 centipoises. ##STR1## wherein each of R 1 , R 2 and R 3 represents hydrogen, methyl, ethyl or phenyl, R 4 stands for --C n H 2n --(n is an integer from 1 to 10) or phenylene, each of R 5 and R 6 represents hydrogen or --C n H 2n+1 (n is an integer from 1 to 5), each of X and Y is an integer from 1 to 100,000 (X+Y>10), and A represents hydrogen, --C 2 H 4 O) m H, --C 3 H 6 O) n H, (each of m and n is an integer from 1 to 10), ##STR2## wherein each of R 7 and R 8 is hydrogen, phenyl or alkyl having not more than 10 carbon atoms.
It is necessary that the silicone oil should be given to acrylic fibers in an amount of 0.1-5 weight % based on the weight of the fibers. With an amount less than 0.1 weight %, it is difficult to display the effect of the present invention sufficiently. However, even if too large an amount of the silicone oil is given to the fibers, a higher effect cannot be produced, and therefore such an amount is unprofitable from the viewpoint of economy. Accordingly, it is necessary that the upper limit of the amount of the silicone oil to be given to the fibers should be 5 weight % based on the weight of the fibers.
The specific oils to be given to the fibers together with said silicone oils are selected from glycerine, polyethylene glycol, polypropylene glycol, alkyl derivatives thereof, mixtures or compounds of two or more of these substances. As the alkyl derivatives, there can be mentioned ether compounds with alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentanol, hexanol, etc. and ester compounds with lower carboxylic acids or oxycarboxylic acids such as formic acid, acetic acid, oxalic acid, malonic acid, succinic acid, butyric acid, lactic acid, malic acid, etc. The mixture means a mere mixture of the above-mentioned substances, and the compound means, for example, a block-copolymer of polyethylene glycol with polypropylene glycol.
The specific oils used in the present invention must be those that generate no substantial residue or if any, a very slight amount of residue, under a predetermined action of heat. That is to say, the specific oils must be selected from those that give an amount of residue less than 5 weight %, when the oils are exposed to a temperature of 240° C. for one hour.
Results of residue tests (240° C.×1 hour) made for some of the oils of the present invention and usual spinning oils are given below:
______________________________________ Residue after heat decom-Substances tested position (%)______________________________________Sodium stearate 50-70Sodium oleate 50-70Sodium laurate 50-70Sodium salt of lauryl phosphate/polyethy-lene oxide addition product 50-70Mixture of sorbitan monolaurate/ethyleneoxide addition product and polyethyleneglycol oleic acid ester (50/50) 60Sodium sulfosuccinic acid diisooctyl ester 40-50Polyethylene glycol (400) lauric acid ester 40-50Polyethylene glycol (400) stearic acid ester 30-40Polyethylene glycol (100) oleic acid ester 30-40Glycerine monooleic acid ester ethylene oxideaddition product 20-30Alkyl phenol ether ethylene oxide additionproduct 20-30Glycerine 0Dipropylene glycol 0Polypropylene glycol (1,000) 0.1Polypropylene glycol (4,000) 0.2Polyethylene glycol (400) 1.6Polyethylene glycol (2,000) 2.2Polyethylene glycol (400) glycerine ether 0.5Polyethylene glycol (400) dipropylene ether 1.2Glycerine monoacetic acid ester 0.3Polyethylene glycol (1,000)/polypropyleneglycol (2,000) block copolymer 0.7Polypropylene glycol (2,000) diisoamyl ether 3.5______________________________________
The residue tests were carried out as follows:
Ten grams of the oil to be tested is put into a flat dish made of aluminum, 8.5 cm in diameter and 1.0 cm in depth, and is then heated in a hot air current drying apparatus at 240° C. and at an air current velocity of 2 m/sec. for one hour. The weight of the residue (X g) is accurately measured, and the decomposition residue (%) is evaluated by the following formula:
Decomposition residue (%)=(X/10)×100
It goes without saying that the specific oils according to the present invention are not limited to the above-mentioned ones shown in the residue tests, and other oils satisfying said two requirements can be advantageously employed, as mentioned previously. It is necessary to introduce such a specific oil into acrylic fibers finally in an amount of 0.1-5 weight % based on the weight of the fibers. If the amount of the oil is less than 0.1%, the objects of the present invention cannot be effectively attained, and in case the amount exceeds 5%, the fibers become sticky or soil the thermal stabilization oven or rollers, and therefore such amounts are not desirable.
To introduce the silicone oil and the specific oil into acrylic fibers in the present invention, combinations of the following methods are suitably used, whereby the silicone oil and the specific oil can be dispersed and introduced into the acrylic fibers before thermal stabilization treatment.
A method wherein the silicone oil and/or the specific oil are added to the spinning solution and then the spinning solution is spun; a method wherein acrylic fibers in a water-swollen state obtained by spinning are treated with the silicone oil and/or the specific oil so that these oils are contained in the fibers; a method wherein acrylic fibers after drying and before thermal stabilization are treated with the silicone oil and/or the specific oil so that these oils are contained in the fibers; etc. The amount of introduction can be attained by suitably deciding the amounts of the silicone oil and the specific oil to be added.
As for the application means for the silicone oil the specific oil used in the present invention, the acrylic fibers can be treated, in accordance with the above-mentioned methods, with an aqueous solution of these oils or a solution in which these oils are dissolved in a low boiling point solvent such as acetone, carbon tetrachloride, benzene, etc.
Upon producing carbon fibers from the acrylic fibers containing such a particular silicone oil and specific oil, any conventional, known heat treating methods may be employed. But in general, there is employed a heat treating method consisting of a thermal stabilization step in which the fibers are heated in an oxidizing atmosphere at a temperature between 200° C. and 350° C. and a carbonization step in which the fibers are heated in a non-oxidizing atmosphere or under reduced pressure at a higher temperature above 800° C. As the thermal stabilization atmosphere, air is preferred, but other methods can be employed in which the fibers are thermally stabilized in the presence of sulfur dioxide gas or nitrogen monoxide gas, or under irradiation of light. As the carbonization atmosphere, nitrogen, hydrogen, helium, argon, etc. are used by preference. To produce carbon fibers with higher strength and higher modulus of elasticity, it is desirable to heat the fibers under tension (generally 0.1-0.5 g/d). Especially, it is effective to apply tension upon thermal stabilization treatment and upon carbonization or graphitization treatment.
For a better understanding of the present invention, representative examples are shown in the following. In the examples, percentages and parts are by weight unless otherwise indicated.
EXAMPLE 1
A spinning solution prepared by dissolving an acrylonitrile copolymer consisting of 98.5 mol % acrylonitrile and 1.5 mol % methacrylic acid in a 50% aqueous sodium thiocyanate solution, was extruded through a spinnerette (having 40,000 spinning holes) into a 12% aqueous sodium thiocyanate solution to coagulate the spinning solution into fibers. The fibers were then washed with water, cold-stretched, and further stretched 4 times in length in boiling water to obtain a water-swollen acrylic fiber tow with a water content of 135%. Thereafter, the water-swollen fiber tow was immersed into an aqueous dispersion of polydimethylaminosiloxane (1,500 centipoises at 25° C.) and was then dried at 120° C. In this way, an acrylic fiber tow of a single-filament fineness of 1.5 denier containing the above-mentioned aminosiloxane in an amount of 0.3% was obtained.
Thereafter, this tow was immersed in an aqueous solution of polyethylene glycol (400) and the mangle squeeze ratio was regulated to produce Sample No. 1 to No. 6 shown in Table 1. These acrylic fiber samples were supplied to a heating oven (180° C.) through guides and rollers, and further supplied to the thermal stabilization step. The state of static electricity generation and the operational condition during this step are also set forth together in Table 1.
TABLE 1______________________________________ Amount of theSample specific oil Static electri- OperationalNo. introduced (%) city generation condition______________________________________1 0.05 A little large Considerably bad2 0.1 No generation Good3 0.25 " "4 0.50 " "5 4.80 " "6 10.20 " A little bad; rollers were soiled.7 0 Remarkable Remarkably bad______________________________________
From the results in Table 1, it is understood that good operational condition was obtained only when the prescribed amounts of the two kinds of the specific oils according to the present invention were introduced into the fibers.
EXAMPLE 2
The acrylic fibers of Sample Nos. 3 and 5 shown in Example 1 were continuously supplied to the heating oven used in Example 1 so that the residence time of the fibers in said oven should be 3 minutes. The fibers were further introduced into a thermal stabilization oven at 240° C. to object the fibers to thermal stabilization treatment for 60 minutes, and then the fibers were subjected to carbonization treatment in a nitrogen atmosphere at 300°-800° C. for 2 minutes and at 800°-1300° C. for 1 minute.
On the other hand, fibers (Sample No. 8) prepared by causing the acrylic fibers of Sample No. 7 shown in Example 1 to ontain a mixed oil of polyethylene glycol (1000) sorbitan monolaurate/polyethylene glycol (400) oleic acid ester (50/50) in an amount of 0.45%, and fibers (Sample No. 9) prepared by causing the same acrylic fibers of Sample No. 7 to obtain lauric acid ethylene oxide addition product in an amount of 0.4%, where carbonized by the same method as above. The physical properties of the carbon fibers thus obtained are shown in Table 2.
TABLE 2______________________________________Carbon fibersSample Tensile TensileNo. modulus strength Appearance______________________________________3 24.6 ton/mm.sup.2 288 kg/mm.sup.2 No fluff5 24.3 ton/mm.sup.2 297 kg/mm.sup.2 No fluff8 22.7 ton/mm.sup.2 209 kg/mm.sup.2 Much fluff9 21.5 ton/mm.sup.2 182 kg/mm.sup.2 Much fluff______________________________________
During the heat treatment of Sample No. 8 and No. 9, a pitch- or tar-like substance was produced owing to the oil used, and consequently agglutination or fusion among the carbon fibers was caused, and yarn breakage occurred frequently.
EXAMPLE 3
By employing the same method as in Example 1 except that the silicone oils shown in Table 3 were used in place of the polydimethylaminosiloxane used in Example 1, dry acrylic fiber tows were obtained.
The amounts of the silicone oils contained in the fibers are shown in Table 3. Thereafter, the dry fibers were immersed into the aqueous solutions of glycerine described in Table 3 (the glycerine contents in the fibers were varied as in Table 3). In this way, acrylic fiber tows of Sample No. 10 to No. 21 were produced. Thereafter, these acrylic fiber tows were carbonized by the method of Example 2.
The physical properties of the thus-obtained carbon fibers and the state of static electricity generation in the heat treatment step are shown in Table 3.
TABLE 3__________________________________________________________________________Kind of silicone Glycerine Carbon fibers StaticSampleoil and content content Tensile Tensile electricityNo. (%) (%) modulus strength generation__________________________________________________________________________10 Silicone A 0.52 0.60 24.8 ton/mm.sup.2 258 kg/mm.sup.2 No11 Silicone A 5.35 0.60 22.5 ton/mm.sup.2 245 kg/mm.sup.2 No12 Silicone B 0.43 0.60 24.3 ton/mm.sup.2 275 kg/mm.sup.2 No13 Silicone B 0.43 0.05 23.8 ton/mm.sup.2 252 kg/mm.sup.2 Much14 Silicone C 0.35 0.50 23.7 ton/mm.sup.2 263 kg/mm.sup.2 No15 Silicone C 0.35 5.28 23.5 ton/mm.sup.2 235 kg/mm.sup.2 No16 Silicone D 0.47 0.80 24.5 ton/mm.sup.2 280 kg/mm.sup.2 No17 Silicone D 5.35 5.28 22.8 ton/mm.sup.2 242 kg/mm.sup.2 No18 Silicone E 0.34 0.80 24.2 ton/mm.sup.2 256 kg/mm.sup.2 No19 Silicone E 0.05 0.05 22.3 ton/mm.sup.2 185 kg/mm.sup.2 Much20 Silicone A 0.50 0.50 24.6 ton/mm.sup.2 256 kg/mm.sup.2 No21 Silicone A 0.05 0.50 22.2 ton/mm.sup.2 190 kg/mm.sup.2 Much__________________________________________________________________________Note: Silicone A Polydimethyl- 500 centipoises at 25° C. siloxaneSilicone B Polymethyl- 150 centipoises at 25° C. phenylsiloxaneSilicone C Methylhydrogen 100 centipoises at 25° C. polysiloxaneSilicone D Polydimethyl- 3500 centipoises at 25° C. siloxane ethylene oxide propylene oxide block copolymerSilicone E Polydimethyl- 200 centipoises at 25° C. siloxane epoxy derivative__________________________________________________________________________
As shown in Table 3, it is clearly understood that in every case wherein the amounts introduced of the silicone oils and the specific oils are within the range recommended in the present invention, high quality carbon fibers can be obtained, and that the winding of the fibers around the guides and rollers in the carbonization step does not occur at all, so that the operational condition can be remarkably stabilized.
EXAMPLE 4
A spinning solution obtained by dissolving the same acrylonitrile copolymer used in Example 1 in a 50% aqueous sodium thiocyanate solution, was extruded through a spinnerette once into air, and thereafter it was introduced into a 13% aqueous sodium thiocyanate solution to coagulate it into fibers. The fibers were then washed with water, and stretched in hot water to obtain water-swollen fibers. Thereafter, the water-swollen fibers were immersed into an aqueous mixed dispersion of the polydimethylaminosiloxane as used in Example 1 and polyethylene glycol, and then the fibers were dried at 120° C. In this way, acrylic fibers (Sample No. 22), 1.3 deniers in single-filament denier, containing the above-mentioned aminosiloxane and polyethylene glycol in amounts of 0.47% and 0.35%, respectively. The fibers were then stretched 20% in a heating oven at 220° C., and were subjected to a thermal stabilization treatment at 245° C. for 30 minutes and 260° C. for 15 minutes, followed by carbonization.
The physical properties of the thus obtained fibers were excellent, the modulus of elasticity being 25.3 ton/mm 2 , and the strength being 371 kg/mm 2 . Upon supplying the thermally stabilized fibers to the carbonization oven, there was no generation of fluff or no winding of the fibers around the guides and rollers. Thus, it was possible to produce carbon fibers having an excellent appearance.
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The present invention relates to a process for producing carbin fibers which involves thermally stabilizing and carbonizing or graphitizing acrylic fibers containing 0.1-5 weight %, based on the weight of the fibers, of a straight chain silicone substance and further containing 0.1-5 weight %, based on the weight of the fibers, of a chemical substance which is selected from glycerine, polyethylene glycol, polypropylene glycol, alkyl derivatives thereof, and mixtures or compounds of two or more of these substances, and which generates only a residue less than 5 weight % under the action of heat at 240° C. for one hour. According to applicant's invention, such problems as fluffiness, spreading, filament breakage etc. can be greatly reduced and it is possible to produce fibers free from agglutination or fusion and having high strength and high modulus of elasticity by heat-treatment in a short time.
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STATEMENT OF RELATED APPLICATIONS
This patent application is a continuation-in-part of U.S. patent application Ser. No. 11/576,864 having a fling date of 6 Apr. 2007, which is the Patent Cooperation Treaty (PCT) Chapter II National Phase of, and claims priority on, PCT International Patent Application No. PCT/BR2004/000202 having an International Filing Date of 15 Oct. 2004, both of which are incorporated herein by this reference.
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention is concerned with pharmaceutical compositions containing new substances isolated from Cassia spectabilis (sin. C. excelsa, Senna spectabilis ) as well as their semi-synthetic derivatives. In particular, the compositions derived from the present invention have demonstrated an acetylcholinesterase inhibitory profile, thus being useful in the treatment of memory related disorders and neurodegenerative diseases, such as Alzheimer's Disease and Parkinson's Disease. The present invention is also concerned with the processes of obtaining those compounds.
2. Related Art
Alzheimer's Disease (AD) is a neurodegenerative disease of great social-economic impact, being the cause of about 50-60% of the total number of dementia among people aged over 65 years old (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137). AD affects around 1.5% of the population with 65-69 years old, 21% with 85-86 years old and 39% with 90 years old or more, affecting approximately 15 million people in the world. This disease is considered one of the main health problems due to the tremendous impact to the patient, families, to the health system and to the society as a whole, since half of AD victims are inpatients at health institutions and the remaining half receive care treatment at home, involving families, relatives and friends. Quite often, AD patient care treatment brings tremendous emotional, psychological and financial stresses to the families involved, since treatment is expensive and the patient gradually loses their motor and cognitive functionalities, to the point of not recognizing close relatives. Scientists estimate that around 4 million people have AD and that AD incidence in the population over 65 years old duplicates every 5 years. Moreover, in the most industrialized countries, people over 65 years old are one of the most growing segments of the population, probably reaching at least 19 million people by the year 2050. Estimates say that half of this people will develop some form of AD.
The progressive degenerative process of psychomotor and cognitive functions, originally described by the German pathologist Alois Alzheimer in 1907, lasts about 8.5 to 10 years, from the appearance of the first symptoms until death occurs. The brain regions associated to high-level functions, particularly the neocortex and the hippocampus, are the most compromised by the biochemical alterations produced by AD (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137; Michaelis, M. L.; J. Pharm. Exper. Ther. 2003, 304, 897; Gooch, M. D.; Stennett, D. J.; Am. J. Health Syst. Pharm. 1996, 53, 1545). The occurrence of extracellular deposition of β-amyloid peptide (derivate from amyloid protein precursor—APP) in senile platelets and the erratic formation of intracellular neurofibriles (containing an abnormal phosphorilated form of a protein associated to microtubules—TAU) (Gooch, M. D.; Stennett, D. J.; Am. J. Health Syst. Pharm. 1996, 53, 1545; Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137) are among the most evident causes of AD genesis. This process results in a loss of the neuronal function and synaptic damage, with subsequent compromising of memory, motor coordination and reasoning, added to loss of cognitive capacity and dementia.
At the cellular level, AD is associated to the reduction of acetylcholine (ACh) in the synaptic process, reducing the cortical cholinergic neurotransmission, apart from other neurotransmitters such as noradrenalin, dopamine, serotonin, glutamate and, in lower levels, substance P (Rufani, M.; Filocamo, L.; Lappa, S.; Maggi, A.; Drugs in the Future 1997, 22, 397; Tabarrini, O.; Cecchetti, V.; Temperini, A.; Filipponi, E.; Lamperti, M. G.; Fravolini, A.; Bioorg. and Med. Chem. 2001, 9, 2921). Recent studies demonstrated the reduction of the number of nicotinic and muscarinic (M 2 ) receptors for ACh, most of them present at pre-synaptic cholinergic terminations, with preservation of muscarinic (M 1 and M 2 ) post-synaptic receptors (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137).
The acetylcholine is biosynthesized from acetyl-coenzyme A (acetyl-coA) and choline by action of acetylcholinetransferase, which transfers an acetyl radical to choline, regenerating the Coenzyme-A. This neurotransmitter is found in the brain and in the neuromuscular junctions, composing part of the parasympathetic nervous system. The contraction of smooth muscles, blood vessels dilation and the control of heart beating are direct effects of ACh; in the brain, it is involved in the synaptic process and it is associated with motor control, memory and cognition. Its activity and permanence in the synaptic gap is regulated by acetylcholinesterase (AChE) catalyzed hydrolysis, which regenerates choline, its precursor. The active site of AChE responsible for the hydrolysis process is composed by a catalytic triad of serine (SER 200), hystidine (HIS 440) and glutamate (GLU 327). The AChE hydrolysis mechanism occurs by nucleophilic attack from serine to the carbonylic carbon of ACh, generating a tetraedric intermediate, stabilized by hydrogen bonds, producing free choline and acetylated serine. At the end, the hydrolysis of the serine acetyl group by water recovers the enzymatic site.
The basis of the cholinergic hypothesis is related to the capacity of drugs that, enhancing the central cholinergic function, could improve cognition and, perhaps, some of the behavioral effects induced by the disease. There are many alternatives to the correction of the cholinergic deficit, most of them focusing the substitution of ACh precursors (choline or lecithin). Nevertheless, these agents did not increase the central cholinergic activity (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137). Other studies investigated the use of cholinestarase inhibitors (ChE) for reducing ACh hydrolysis, e.g., phisostigmine. Recently, therapeutic approaches involving specific agonists of muscarinic receptors (M 1 ) and nicotinic or muscarinic antagonists (M 2 ) have been explored (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137; Gooch, M. D.; Stennett, D. J.; Am. J. Health Syst. Pharm. 1996, 53, 1545). Advances in the understanding of the evolution and molecular pathology of AD have shown that the use of AChE inhibitors should be the most efficient form of therapeutic approach to AD (Francis, P. T.; Palmer, A. M.; Snape, M.; Wilcock, G. K.; J. Neurol Neurosurg Psychiatry 1999, 66, 137; Rufani, M.; Filocamo, L.; Lappa, S.; Maggi, A.; Drugs in the Future 1997, 22, 397; Tabarrini, O.; Cecchetti, V.; Temperini, A.; Filipponi, E.; Lamperti, M. G.; Fravolini, A.; Bioorg. and Med. Chem. 2001, 9, 2921; Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199; Quik, M.; Jeyarasasingam, G.; Eur. J. Pharmacol. 2000, 393, 223).
One of the therapeutic approaches to AD is the development of direct agonists of M 1 post-synaptic muscarinic receptors. As concrete examples of this research line, one could cite U.S. Pat. No. 4,211,867, U.S. Pat. No. 4,414,211 and U.S. Pat. No. 6,093,733, all of them describing new muscarinic agonist compounds. The stimulation of these receptors increased the cognition capacity in animals. However, despite the efforts in the development of M 1 agonists, many of the compounds tested have shown low selectivity, apart from various side effects due to the activation of M 3 receptors in the intestine, bladder and lung. M 1 non-selective agonists can also interact with M 4 and M 5 receptors in the central nervous system (CNS), with consequences not yet completely determined. Another possible cholinergic approach would be the development of antagonists to post-synaptic M 2 autoreceptors. Pharmacological data from animal models have demonstrated that the blocking of these receptors contributes to the increase of ACh levels and promotes better results in tests measuring the cognition capacity. Despite of the big number of potent M 2 antagonists published, very few show considerable selectivity when compared to other muscarinic receptors subtypes (Greenlee, W.; Clader, J.; Asberom, T. et al.; II Farmaco 2001, 56, 247).
The initial observation that muscarinic antagonists, such as scopolamine, produced deficits in short-term memory, lead to the idea that the cholinergic deficit was, predominantly, of muscarinic nature. However, this point of view changed due to a series of evidences, including autoradiographic and hystochemical studies from cerebral tissue autopsy, and also studies on brain images of patients, which demonstrated a more extensive specific loss of nicotinic receptors, in AD, in comparison to muscarinic receptors (Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199; Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165; Maelicke, A.; Samochocki, M.; Jostock, R.; Fehrenbacher, A.; Ludwig, J.; Albuquerque, E. X.; Zerlin, M.; Biol. Psych. 2001, 49, 279).
Nowadays, there are many evidences showing that nicotinic drugs affect learning and memory. Nicotine and other nicotinic agonists can improve cognitive and psychomotor functions, while nicotinic antagonists cause cognitive deficit. Moreover, the occurrence of AD in smokers is smaller than in non-smokers, what may be associated to the overexpression of nicotinic receptor for ACh (nAChRs) observed in the brain of smokers. Thus, nicotinic drugs may exhibit chronic and acute effects in the cognitive function and, in addition, neuroprotection may be one of the chronic effects (Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165). Based on these findings, some scientists are looking for, with reasonable success, the creation of new nicotinic agonists, as in the case of WO 02/44176, WO 94/04152 and WO 03/022856.
Nicotinic receptors are expressed as various subtypes in mammals, being α4β2 and α7 subtypes the most prominent and present in post-, pre-, peri-, and extra-synaptic locations. The nAChR α7 subtype receptors actions are very similar to subtype α4β2, but presenting a much higher permeability to Ca ++ , faster desensibilization and different pharmacology, including activation by Ch and blocking by α-bungarotoxin (a snake toxin) (Maelicke, A.; Samochocki, M.; Jostock, R.; Fehrenbacher, A.; Ludwig, J.; Albuquerque, E. X.; Zerlin, M.; Biol. Psych. 2001, 49, 279). Due to choline sensitivity, nicotinic receptors α7 can be chemically excited even after the natural neurotransmitter being cleaved. Thus, this receptor subtype can respond not only to synaptic events, originated from the release of ACh, but also to volume alterations in the concentration of ACh/Ch. Moreover, due to its high permeability to Ca ++ ions, the activation of α7 receptors can produce metabotropic responses in excited cells, including the Ca ++ controlled release of transmitters and stimulation of genetic transcription and protein biosynthesis (Maelicke, A.; Samochocki, M.; Jostock, R.; Fehrenbacher, A.; Ludwig, J.; Albuquerque, E. X.; Zerlin, M.; Biol. Psych. 2001, 49, 279; Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165; Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199).
Recently, three main strategies have been applied to balance nicotinic cholinergic deficits: stimulation of the ACh synthesis, inhibition of ACh degradation and administration of nicotinic receptors agonists. Actually, no therapeutic breakthrough has been obtained through the administration of ACh precursors; the administration of cholinesterase inhibitors, are the most common therapeutic alternative, producing the best results. Nevertheless, these inhibitors have limited therapeutic value and, in the great majority of the cases, are not capable in preventing the progression of AD at all (Maelicke, A.; Samochocki, M.; Jostock, R.; Fehrenbacher, A.; Ludwig, J.; Albuquerque, E. X.; Zerlin, M.; Biol. Psych. 2001, 49, 279; Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165; Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199).
Many nicotinic receptors agonists are in clinical and pre-clinical trials, although of difficult dosage; higher levels may cause greater desensibilization than activation of nicotinic receptors. Other challenges, presently not solved, include the transport of the drug to the target brain nicotinic receptor (specific subtype of receptor) and the receptor subtype selectivity (Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165).
Given the latest breakthroughs in term of nicotinic receptors (physiology, biochemistry and genetic expression) and its effective participation in the events related to AD, the application of these receptors allosteric modulators has turned out to be a new strategy in the treatment of AD. Allosteric modulators are substances that interact with receptors through binding sites other than those used by ACh and by nicotinic antagonists and agonists. Since AD is associated to the reduction of nicotinic neurotransmission, allosteric modulators enhance the activity of nicotinic receptor channels in response to ACh. These properties gave birth to a new class of nACHR ligand, the allosteric potentiators ligands (APL) (Maelicke, A.; Samochocki, M.; Jostock, R.; Fehrenbacher, A.; Ludwig, J.; Albuquerque, E. X.; Zerlin, M.; Biol. Psych. 2001, 49, 279; Maelicke, A.; Albuquerque, E. X.; Eur. J. Pharmacol. 2000, 393, 165; Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199).
The collinergic hypothesis is the most accepted biochemical theory and one of the most effective therapeutic strategies in the treatment of AD. Among the various mechanisms for increasing the cholinergic transmission, the inhibition of the acetylcholinesterase enzyme (AChE), a tetrametric protein responsible for the metabolic cleavage of ACh, is the most efficient method to improve the cholinergic deficit by increasing ACh levels in the central nervous system (CNS) and leading to a symptomatic improvement.
In spite of the fact that Miasthenia Gravis (MG) is associated to a reduced number of cholinergic receptors in the neuromuscular junction, differently from Alzheimer Disease, where one finds neurotransmitter deficit, the hypothesis that the neurotransmitter metabolism phase via AChE inhibition could also alleviate MG symptoms exists. Thus, independently from a complete knowledge of the mechanisms involved, the availability of the new molecules, as the ones of the present invention, may be useful in the treatment of MG.
Among the available drugs in the market for the treatment of AD, tacrine (THA, Cognex®) was the first (synthetic) drug approved by the FDA (Food and Drug Administration) in the United States for therapeutical use, presenting a moderate effect, but meaningful in the relief of symptoms of moderate and low intensity forms of AD. However, its use is limited due to serious side effects, such as hepatotoxicity, forcing patients to interrupt the treatment (Rufani, M.; Filocamo, L.; Lappa, S.; Maggi, A.; Drugs in the Future 1997, 22, 397). Besides tacrine, at the present moment three other drugs are being commercialized in the USA and Europe for the treatment of AD: donepezil (Aricept®), rivastigmine (Exelon®) and galanthamine (Reminyl®). Among those, THA, donezepil and galanthamine are reversible AChE inhibitors, being galanthamine a natural product recently approved by FDA and serving as a prototype for the development of anticholinesterasic drugs (Rufani, M.; Filocamo, L.; Lappa, S.; Maggi, A.; Drugs in the Future 1997, 22, 397; Michaelis, M. L.; J. Pharm. Exper. Ther. 2003, 304, 897).
The structural diversity of known IAChEs and the possibility of exploring several mechanisms of action stimulated phitochemical studies over various vegetal species and over microorganisms, which may provide new models for anticholinesterasic substances. In this sense, various vegetal and microorganism species have been studied due to their popular use or ethno-botanic data. One of the most known examples of phytomedicine are Ginkco extracts. Ginkco biloba ( Ginkgoaceae ) is a tree that has been used for centuries in the traditional Chinese medicine for improving alertness. Today, Ginkco is probably the most used vegetal extract for improving cognitive function. Its use prevails specially in Europe, being recently approved in the treatment of dementia by the German Bundesgesundheit Association. Most of the evidences suggest that the enhancement of the cognitive function is associated to the use of a standard extract, the EGb 761. Measurement of the cognitive effects have been made on attention, learning, short-term memory, reaction time and choice time tests, but results appear to be not reproducible between different populations. Moreover, many studies have been published in journals of restricted circulation, what makes access to information harder; the majority of experiments in vivo, both in animals and humans, is restricted to a small number of individuals, compromising a conclusive and broad evaluation of the results (Gold, P. E.; Cahill, L.; Wenk, G. L.; Psych. Sci. Publ. Int. 2002, 3, 2).
Some studies using patients treated with a standard extract of Ginkco biloba and with placebo revealed effects compared to the ones obtained with donepezil, which is the drug of choice for the treatment of AD. Apparently, many of the protection effects over the CNS associated to the chronic use of Ginkco extract are related to the presence of terpenic components and flavonoids with antioxidant and anti-inflammatory properties. These substances can act in different forms, contributing to neuronal tissue integrity: (a) by inhibiting the activity of the superoxide dismutase and monoamino oxidase, which generate free radicals in the brain and in the body; (b) by capturing free radicals which may cause neuronal damage and consequently delay brain changes associated to the aging; (c) by reducing the release of arachdonic acid, a toxic co-product from lipid metabolism that appears in the brain just after an ischemic episode (Gold, P. E.; Cahill, L.; Wenk, G. L.; Psych. Sci. Publ. Int. 2002, 3, 2).
The necessity of turning research for phitochemical components, animals and microorganisms more objective and less expensive, lead to the development of numerous techniques of chemical and biochemical assays for monitoring and selection of biologically and pharmacologically useful extracts, extract fractions and pure substances. Regarding the search for AChE inhibitors, two bioautographical assays in thin layer chromatography have been recently developed (Hostettmann, K.; Queiroz, E. F.; Vieira, P. C.; Princípios Ativos de Plantas Superiores, 1 a . ed., EdUFSCar: São Carlos, 2003). Marston and cols. (Marston, A.; Kissiling, J.; Hostettmann, K. A.; Phytochem. Anal. 2002, 13, 51) used an azoic colorant to identify the activity of AChE over 1-naftyl acetate; in another case Rhee and coleagues (Rhee, I. K.; van der Meent, M.; Ingkaninan, K.; Verpoorte, R.; J. Chromatography A 2001, 915, 217) used 5,5′-dithiobis(2-nitrobenzoic acid) (Ellmann's reagent) for the visualization of the enzymatic activity. Apparently, the only inconvenient in the use of Ellmann's reagent is the limit of visual detection, since in both cases white inhibition rings are formed over a blue colored plate (Marston and cols. assay) (Marston, A.; Kissiling, J.; Hostettmann, K. A.; Phytochem. Anal. 2002, 13, 51) and over a yellow colored plate (Rhee and cols. assay) (Hostettmann, K.; Queiroz, E. F.; Vieira, P. C.; Principios Ativos de Plantas Superiores, 1 a . ed., EdUFSCar: São Carlos, 2003).
A recent study with Brazilian plants (Trevisan, M. T. S.; Macedo, F. V. V.; van de Meent, M.; Rhee, I. K.; Verpoorte, R.; Química Nova, 2003, 26, 301) used the bioautographical assay of Rhee and cols. and Ellmann's assay in microplates to identify extracts which could contain AChE inhibitor substances (Rhee, I. K.; van der Meent, M.; Ingkaninan, K.; Verpoorte, R.; J. Chromatography A 2001, 915, 217; Ellmann, G. L.; Biochem. Pharmacol. 1961, 7, 88). Studies were made over 58 extracts of 30 species of various vegetal genuses, where authors considered an inhibition factor equal or greater than 50% as selection criteria for chemical fractionation. From the preliminary work, Paullinia cupana (guaraná), Amburana cearensis (cumaru) and Lippia sidoides were the species that demonstrated the best results, inhibiting from 65 to 100% of the enzymatic activity in both bioassays. In the case of guaraná, a positive effect on memory gain was observed after chronic and acute administration; up to now, 12 coumarins were isolated through the biodirected fractionation of extracts from A. cearensis and L. sidoides , demonstrating the usefulness of this type of assay for bioprospection of new anticholinesterasic drugs.
Galanthamine is an alkaloid isolated from various vegetal species of the Amaryllidaceae family and has revealed itself an AChE inhibitor of long, selective, reversible and competitive action, with therapeutic effects lasting even after the end of treatment (López, S.; Bastida, J.; Viladomat, F.; Codina, C.; Life Sciences 2002, 71, 2521). This is due to its double action mechanism: acting as an AChE inhibitor and on brain nicotinic receptors. The modulation of these receptors amplifies the neurotransmission of the AChE signal and characterizes a breakthrough in the design of drugs and AD treatments through nicotinic receptors allosteric modulator drugs (Rufani, M.; Filocamo, L.; Lappa, S.; Maggi, A.; Drugs in the Future 1997, 22, 397; Maelicke, A.; Schrattenholz, A.; Samochocki, M.; Radina, M.; Albuquerque, E. X.; Behavioural Brain Res. 2000, 113, 199; Quik, M.; Jeyarasasingam, G.; Eur. J. Pharmacol. 2000, 393, 223). The galanthamine acts by binding to the active site of cerebral AChE and also stimulates pre-synaptic and post-synaptic nicotinic receptors which can increase the release of neurotransmitters such as ACh and glutamate, directly stimulating the neuronal function (Fennel, C. W.; van Staden, J.; J. Ethnopharm. 2001, 78, 15). An excellent example among patents involving galanthamine analogs able to allosterically bind to receptors can be found in document WO 01/43697.
Another alkaloid isolated from Narcissus L. (Amaryllidaceae), the sanguinine (9-O-desmethylgalanthamine), proved to be 10 times more active than galanthamine itself in in vitro tests. The search for other AChE inhibiting substances (IAChE) in this vegetal genus, lead to the isolation of other two biologically active derivatives from galanthamine, the 11-hydroxigalanthamine and the epinorgalanthamine. Another structural type of alkaloid, licorine-like, has been isolated from this genus, being its most biologically active components the oxoassoanine, the assoanine and the pseudolicorine (López, S.; Bastida, J.; Viladomat, F.; Codina, C.; Life Sciences 2002, 71, 2521).
The study of various vegetal species currently used in Chinese popular medicine and in the Middle East lead to the isolation of various active alkaloids. An example of this is Huperzia serrata (syn.: Lycopodium serratum ), used in a tea preparation prescribed for centuries in China for the treatment of fever and inflammation. The phytochemical study of this plant lead to the isolation of Huperzine A, an interesting candidate for the treatment of CNS disorders and epilepsy, capable of reducing neuronal loss caused by high concentrations of glutamate. It is a selective IAChE, very potent and its systemic use increases the release of ACh, dopamine and norepinephrine and the increase of ACh concentration lasts for up to 6 hours and has practically no action over the butyrylcholinesterase (BuChE) (Chang, J.; Biochem. Pharmacol. 2000, 59, 211; Rajendran, V.; Saxena, A.; Doctor, B. P.; Kozikowski, A. P.; Bioorg. Med. Chem. 2002, 10, 599). A new alkaloid lycopodium -like, the Huperzine P, was obtained from this same plant. However, its activity is lower than Huperzine A's.
Results obtained with Huperzine A encouraged Orhan and cols. to study other 5 lycopodium species in search for others AChE inhibitor metabolites (Orhan, I.; Terzioglu, S.; Sener, B.; Planta Medica 2003, 69, 265). After a preliminary evaluation of the extracts via Ellmann's ssay (Ellmann, G. L.; Biochem. Pharmacol. 1961, 7, 88), the extract of the aerial parts of the L. clavatum was selected and the bio-guided fractionation resulted in the isolation of the α-onocerin. The results from the anticholinesterasic activity demonstrated that the α-onocerine, which has an IC 50 equals to 5.2 μM, was better than donepezil in 1 to 3 mg/mL concentrations and practically equipotent in the 5 mg/mL concentration, though it did not reach the potency of galanthamine at any of the dosages tested. This performance called even more attention to huperzine, intensifying the search for structural analogs and resulting in many patent applications, such as WO 99/11625, WO 92/19238 and EP 806 416.
Some triterpenic alkaloids were isolated from Buxus hyrcana , such as homomoenjodaramine and moenjodaramine, and have proven promising AChE inhibitors (Ur-Rahman, A.; Choudhary, M. I.; Pure Appl. Chem. 1999, 71, 1079). From this family, Buxus papillosa provided other three steroidal alkaloids, selective AChE inhibitors: cycloprotobuxine C, cyclovirobuxeine A and cyclomicrophylline A (Ur-Rahman, A.; Parveen, S.; Khalid, A.; Farroq, A.; Choudhary, M. I.; Phytochemistry 2001, 58, 963).
Zeatine, initially described as an inductor agent of plantule growing, was isolated from Fiatoua villosa , which methanolic extract had been selected, after screening for inhibitory AChE activity. Pure zeatine inhibited AChE activity in a dosage-dependent mode with an IC 50 corresponding to 1.09×10 −4 M (Heo, H-J.; Hong, S-C.; Cho, H-Y.; Hong, B.; Kim, H-K.; Kim, E-K.; Shim, D-H.; Mol. Cells. 2002, 13, 113).
The glycoalkaloids present in high concentrations at tomato skin ( Solanum tuberosum L.) are responsible for many food poisoning cases. The observation of intoxicated patients revealed symptoms as mental confusion, depression and weakness. These effects were associated to the inhibition of AChE by α-solanine and α-chaconine, which correspond to 95% of glycoalkaloids present in S. tuberosum (Smith, D. B.; Roddick, J. G.; Jones, J. L.; Trends in Food and Tech. 1996, 7, 126).
Cultures of microorganisms, especially fungus of diverse families and genus, have been systematically studied as an important source in the search for useful drugs for the treatment of serious diseases such as cancer, malaria and bacterial infections, among many others. Otoguro, Kuno and colleagues (Kuno, F.; Otoguro, K.; Shiomi, K.; lwai, Y.; Omura, S.; J. Antibiot. 1996, 49, 742; Kuno, F.; Shiomi, K.; Otoguro, K.; Sunazuka, T.; Omura, S.; J. Antibiot. 1996, 49, 748; Otoguro, K.; Kuno, F.; Omura, S.; Pharmacol. Ther. 1997, 76, 45), searching candidates for new drugs able to re-establish the neurotransmission system through the systematic screening of natural products produced by fungus, have discovered new AChE inhibitors, the arisugacines. From the soil fungus cultures WK-4164 and FO-4259, cyclophostin and arisugacines A and B were obtained, as well as the already known territrems B and C, and cyclopenine. Among those, arisugacine A, having an IC 50 of 1.0 nM, and arisugacine B, having an IC 50 of 25.8 nM, did not inhibit BuChE even in concentrations 20,000 times superior to 50% of inhibition of AChE activity, demonstrating a high selectivity and resulting in patented research and innovation as, for example, patent U.S. Pat. No. 6,384,045.
On the other hand, territrems B and C showed a lower selectivity, although their low IC 50 , corresponding to 7.6 nM and 6.8 nM, respectively. The cyclopenine was the less active, with an IC 50 of 2,040 nM; however, it was quite selective, not inhibiting BuChE in concentrations up to 2,000 times higher to its IC 50 . The cyclophostin, although very potent, with an IC 50 of 1.3 nM, was the less selective substance, inhibiting BuChE in dosages 35 times its IC 50 (Shiomi, K.; Tomoda, H.; Otoguro, K.; Omura, S.; Pure Appl. Chem. 1999, 71, 1059; Kuno, F.; Otoguro, K.; Shiomi, K.; lwai, Y.; Omura, S.; J. Antibiot. 1996, 49, 742; Kuno, F.; Shiomi, K.; Otoguro, K.; Sunazuka, T.; Omura, S.; J. Antibiot. 1996, 49, 748; Otoguro, K.; Kuno, F.; Omura, S.; Pharmacol. Ther., 1997, 76, 45).
Territrems A, B and C had already been isolated from Aspergillus terreus cultures and, despite the low selectivity demonstrated by the studies of Otoguro and cols. (Otoguro, K.; Kuno, F.; Omura, S.; Pharmacol. Ther. 1997, 76, 45), territrem B was approximately 20 times more potent than neostigmine in AChE inhibition. These results encouraged Peng (Peng, F-C.; J. Nat. Prod. 1995, 58, 857) to prepare territrem derivates for a structure-activity study. The evaluation of the enzymatic activity through Ellmann's assay did not reveal any potency increase for any of the semi-synthetic territrem derivates, though allowed the identification of the double bond in C-2, of the carbonyl in C-1, and of the intact pyrone unity as the essential pharmacophoric group for anticholinesterasic activity in this series of compounds.
The interest in AChE inhibitors from microorganisms metabolites, monitored by Ellmann's assay, lead Kim and cols. (Kim, W-G.; Song, N-K.; Yoo, I-D.; J. Antibiot. 2001, 54, 831) to investigate cultures of a new fungus, the Penicillium citrinum 90648. The diastereoisomers quinolactacins A1 and A2 were isolated from the solid fermentation of this microorganism. The anticholinesterasic activity evaluation of these substances revealed that isomer A2 presented an inhibitory AChE activity 14 times higher than the diastereoisomer A1. Its effect was dosage-dependent, showing an IC 50 of 19.8 μM, while isomer A1 has presented an IC 50 of only 280 μM. Moreover, the eutomer showed competitive inhibitory activity to the substratum and selective to AChE versus butyrylcholinesterase (BuChE), with an IC 50 of 650 μM, by using tacrine as positive control in all tests (IC 50 BUChE =0.006 μM, IC 50 AChE =0.12 μM, very low selectivity).
Cassia spectabilis , a very well known leguminosae from middle-west Brazil, has been extensively studied by our research group, seeking for piperidine alkaloids presenting bio- and pharmacological activity. The phytochemical study of leaves, fruits and flowers from this leguminosae provided around 12 2,6-alkyl-piperidin-3-ols and derivates that showed weak selective cytotoxity in mutant lineage of Saccharomyces cerevisiae . The poorly significant cytotoxic activity of these alkaloids induced us to explore other pharmacologic assays which could confirm some ethnopharmacologic data of the Cassia genus. Thus, assays for central and peripheral analgesic activity, anti-inflammatory activity and AChE inhibitory activity were performed (Bolzani, V. S.; Gunatilaka, A. A. L.; Kingston, D. G. I., “Bioactive and other piperidine alkaloids from Cassia leptophylla”, Tetrahedron 1995, 51(21), 5929-5934; Moreira, M. S. A.; Viegas Jr., C.; Miranda, A. L. P. Bolzani, V. S.; Barreiro, E. J., “Analgesic profile of (−)-spectaline: a piperidine alkaloid from Cassia leptophylla Vog. (Leguminosae)”, Planta Medica 2003, submitted; Viegas Jr., C., PhD thesis, UNESP-Araraquara/SP, 2003, unpublished data; Viegas Jr., C.; Young, M. C. M.; Bolzani, V. S.; Rezende, A.; Barreiro, E. J., “Estudo Fitoquimico de Cassia leptophylla biomonitorado por linhagens transgenicas de S. cerevisiae”, 24 a Reunião Anual da Sociedade Brasileira de Química, Poços de Caldas-MG, 2001, PN-075; Barreiro, E. J.; Bolzani, V. S.; Viegas Jr. C., “Novos Alcalóides Piperidinicos Isolados das Flores de Cassia leptophylla (Leguminosae), 25 a Reunião Anual da Sociedade Brasileira de Quimica, Poços de Caldas-MG, 2002, PN-058). The biggest amounts of (−)-3-O-acetylspectaline and of (−)-spectaline came from the flowers of this plant, which were submitted to several chemical modifications in order to obtain new derivatives. The chloridrate derivatives LASSBio-767, LASSBio-768 and LASSBio-822 were evaluated in respect to AChE inhibitory capacity ex vivo and demonstrated remarkable anticholinesterasic activity. In spite of the novelty about the molecular structure of these new derivatives, many other piperazinic compounds (the compounds of interest are piperidinic alkaloids) presenting anticholinesterasic activity had already been described, being part of the state of the art. Examples of this intellectual production may be found in documents WO 00/33788, which describes nitrogenated heterocyclics capable of act in neurological disorders and not revealing its mechanism of action, although stating that the compounds are weak inhibitors of AChE, and WO 92/17475, EP 1 300 395 and EP 1 116 716, which describe anticholinesterasic piperidinic and piperazinic derivates, diverse from the compounds introduced here. However, there is no report on the use of the molecules targeted by the present invention as anticholinesterasic substances or for the treatment of memory disorders, neurodegenerative disorders, or intoxications by central action substances.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide pharmaceutical compositions for AChE inhibition. In one aspect of this invention, these pharmaceutical compositions are obtained from piperidine alkaloids from C. spectabilis and their semi-synthetic derivatives, specially the compounds 2-(R)-methyl-3-(R)—O-acetyl-6-(S)-(tetradecyl-13′-one)-piperidine, 2-(R)-methyl-6-(S)-(tetradecyl-13′-one)-piperidin-3-(R)-ol and 2-(R)-methyl-3-(R)—O-ter-butoxycarbonyl-6-(S)-(tetradecyl-13′-one)-piperidine and their respective cloridrates.
The pharmaceutical compositions of the present invention, due to its ability of inhibiting AChE, can be used in the treatment of pathologies associated to cholinergic transmission such as neurodegenerative diseases, e.g. Alzheimer's Disease and Parkinson's Disease, and other pathologies associated to memory deficiency conditions.
In another aspect, the pharmaceutical compositions of the present invention, also due to its ability of inhibiting AChE, can be used in the treatment of other conditions associated to cholinergic transmission, for example, muscular diseases such as Miastenia Gravis and muscular paralysis conditions resulting from the military use of biological and/or chemical agents.
An additional object of this invention is to provide processes for obtaining the pharmaceutical compositions of the present invention
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the effect of tacrine (1 mg/kg) in the reversion of amnesia induced by scopolamine in the water maze test. The histogram shows the escape latency (in seconds) during the 4 days test of the control group (-μ-), scopolamine (-λ-) and tacrine+scopolamine (-⋄-). Values expressed as average and standard deviation; *p<0.05; **p<0.01 Mann-Whitney test.
FIG. 2 presents the effect of the semi-synthetic alkaloid LASSBio-767, in the 1 mg/kg concentration, in the reversion of amnesia induced by scopolamine in the water maze test. The histogram shows the escape latency (in seconds) during the 4 days test of the control group (-μ-), scopolamine (-λ-) and LASSBio-767+scopolamine (-⋄-). Values expressed as average and average standard deviation; *p<0.05; **p<0.01 Mann-Whitney test.
FIG. 3 presents the effect of the semi-synthetic alkaloid LASSBio-767, in the 10 mg/kg concentration, in the reversion of amnesia induced by scopolamine in the water maze test. The histogram shows the escape latency (in seconds) during the 4 days test of the control group (-μ-), scopolamine (-λ-) and LASSBio-767+scopolamine (-⋄-). Values expressed as average and average standard deviation; *p<0.05; **p<0.01 Mann-Whitney test.
FIG. 4 presents the effect of the semi-synthetic alkaloid LASSBio-822, in the 1 mg/kg concentration, in the reversion of amnesia induced by scopolamine in the water maze test. The histogram shows the escape latency (in seconds) during the 4 days test of the control group (-μ-), scopolamine (-λ-) and LASSBio-822+scopolamine (-⋄-). Values expressed as average and average standard deviation; *p<0.05; **p<0.01 Mann-Whitney test.
FIG. 5 presents the absence of the semi-synthetic alkaloid LASSBio-767, in the 1 and 10 mg/kg concentrations, in the reversion of amnesia induced by scopolamine in mice in the inhibitory avoidance assay. Latencies shown are from first (training) and second (retention) test days. Note that the animals treated with LASSBio-767 do not differ from the ones treated only with scopolamine. Values expressed as average and average standard deviation.
FIG. 6 presents the effect of alkaloid LASSBio-822, in the 1 and 3 mg/kg concentrations, in the reversion of amnesia induced by scopolamine in mice in the inhibitory avoidance assay. Latencies shown are from first (training) and second (retention) test days. Note that the animals previously treated with LASSBio-822 show a significant partial reversion of the amnesia induced by scopolamine. Values expressed as average and average standard deviation; *p<0.05; **p<0.01 Mann-Whitney test.
FIG. 7 presents the effect of tacrine, in the 5.6 mg/kg concentration, in the reversion of induced amnesia in the inhibitory avoidance assay. Latencies shown are from first (training) and second (retention) test days. Note that the animals previously treated with tacrine show a complete reversion of the amnesia induced by scopolamine. Values expressed as average and average standard deviation; ***p<0.001 Mann-Whitney test.
FIG. 8 presents the LD50 study of tacrine. The histogram shows the percentage of dead mice 10 to 30 minutes after the administration of different concentrations of tacrine.
FIG. 9 presents the cholinergic side effects induced by the administration of saline ( ), LASSBio-767 ( ), tacrine 10 mg/kg ( ), tacrine 30 mg/kg ( ), and tacrine 50 mg/kg ( ), after 10 to 30 minutes of administration. Values expressed as average and average standard deviation.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
For the purposes of this invention, “pharmaceutical compositions” is understood as any composition containing an active principle, with prophylactic, palliative and/or curative properties, acting towards maintaining and/or restoring homeostasis, being administrated via topic, parenteral, enteral and/or, intrathecal forms. Also for the purposes of this invention, “active principle” is understood by all or any substance expressed by formulas (I) or (II), or its acceptable pharmaceutical salts.
The new substances object of this invention belong to the class of piperidine alkaloids, of general structure (I):
wherein:
n corresponds to an integer number from 2 to 16
R 1 is hydrogen, acyl, alkyl, alcoxyl, cycloalkyl; furyl, tiophenyl, pyridinyl, pyrimidinyl, pyrrolyl, thiazolyl, quinazolyl, isoquinolyl or Phenyl-W;
wherein W is hydrogen, ortho-alkyl, ortho-cycloalkyl, ortho-alcoxyl, ortho-cycloalcoxyl, ortho-thioxy, ortho-aryloxy, ortho-sulfones, ortho-sulfides, ortho-sulfoxides, ortho-sulfonates, ortho-sulfonamides, ortho-amino, ortho-amido, ortho-halo, ortho-carboalkoxy, ortho-carbothioalkoxy, ortho-trihaloalkane, ortho-cyano, ortho-nitro, meta-alkyl, meta-cycloalkyl, meta-alcoxyl, meta-cycloalcoxyl, meta-thioxy, meta-aryloxy, meta-sulfones, meta-sulfides, meta-sulfoxides, meta-sulfonates, meta-sulfonamides, meta-amino, meta-amido, meta-halo, meta-carboalkoxy, meta-carbothioalkoxy, meta-trihaloalkane, meta-cyano, meta-nitro, para-alkyl, para-cycloalkyl, para-alcoxyl, para-cycloalcoxyl, para-thioxy, para-aryloxy, para-sulfones, para-sulfides, para-sulfoxides, para-sulfonates, para-sulfonamides, para-amino, para-amido, para-halo, para-carboalkoxy, para-carbothioalkoxy, para-trihaloalkane, para-cyano or para-nitro.
The new substances also object of this invention belong to the class of derivatives of general structure (I), of general structure (II):
wherein:
n corresponds to an integer number from 2 to 16
R 1 is hydrogen, acyl, alkyl, alcoxyl, cycloalkyl; furyl, tiophenyl, pyridinyl, pyrimidinyl, pyrrolyl, thiazolyl, quinazolyl, isoquinolyl or Phenyl-W;
wherein W is hydrogen, ortho-alkyl, ortho-cycloalkyl, ortho-alcoxyl, ortho-cycloalcoxyl, ortho-thioxy, ortho-aryloxy, ortho-sulfones, ortho-sulfides, ortho-sulfoxides, ortho-sulfonates, ortho-sulfonamides, ortho-amino, ortho-amido, ortho-halo, ortho-carboalkoxy, ortho-carbothioalkoxy, ortho-trihaloalkane, ortho-cyano, ortho-nitro, meta-alkyl, meta-cycloalkyl, meta-alcoxyl, meta-cycloalcoxyl, meta-thioxy, meta-aryloxy, meta-sulfones, meta-sulfides, meta-sulfoxides, meta-sulfonates, meta-sulfonamides, meta-amino, meta-amido, meta-halo, meta-carboalkoxy, meta-carbothioalkoxy, meta-trihaloalkane, meta-cyano, meta-nitro, para-alkyl, para-cycloalkyl, para-alcoxyl, para-cycloalcoxyl, para-thioxy, para-aryloxy, para-sulfones, para-sulfides, para-sulfoxides, para-sulfonates, para-sulfonamides, para-amino, para-amido, para-halo, para-carboalkoxy, para-carbothioalkoxy, para-trihaloalkane, para-cyano or para-nitro.
R 2 is either hydrogen or alkyl with 1 to 9 carbon atoms, and
X is halogen;
The new substances also object of this invention belong to the class of derivatives of general structure (I), of general structure (III):
wherein:
n corresponds to an integer number from 2 to 16
R 1 is hydrogen, acyl, alkyl, alcoxyl, cycloalkyl; furyl, tiophenyl, pyridinyl, pyrimidinyl, pyrrolyl, thiazolyl, quinazolyl, isoquinolyl or Phenyl-W;
wherein W is hydrogen, ortho-alkyl, ortho-cycloalkyl, ortho-alcoxyl, ortho-cycloalcoxyl, ortho-thioxy, ortho-aryloxy, ortho-sulfones, ortho-sulfides, ortho-sulfoxides, ortho-sulfonates, ortho-sulfonamides, ortho-amino, ortho-amido, ortho-halo, ortho-carboalkoxy, ortho-carbothioalkoxy, ortho-trihaloalkane, ortho-cyano, ortho-nitro, meta-alkyl, meta-cycloalkyl, meta-alcoxyl, meta-cycloalcoxyl, meta-thioxy, meta-aryloxy, meta-sulfones, meta-sulfides, meta-sulfoxides, meta-sulfonates, meta-sulfonamides, meta-amino, meta-amido, meta-halo, meta-carboalkoxy, meta-carbothioalkoxy, meta-tri haloalkane, meta-cyano, meta-nitro, para-alkyl, para-cycloalkyl, para-alcoxyl, para-cycloalcoxyl, para-thioxy, para-aryloxy, para-sulfones, para-sulfides, para-sulfoxides, para-sulfonates, para-sulfonamides, para-amino, para-amido, para-halo, para-carboalkoxy, para-carbothioalkoxy, para-trihaloalkane, para-cyano or para-nitro.
R 2 is either hydrogen or alkyl with 1 to 9 carbon atoms, and X is halogen;
For the sake of clearness, the following terminology will be adopted for chloridrate derivatives: LASSBio-767 corresponds to the derivative of general formula (II) where R 1 corresponds to acetyl, R 2 is hydrogen, X is chloride and n is equal to 9; LASSBio-768 corresponds to the derivative of general formula (II) where R 1 corresponds to H, R 2 is hydrogen, X is chloride and n is equal to 9; LASSBio-822 corresponds to the derivative of general formula (II) where R 1 corresponds to t-butoxycarbonyl, R 2 is hydrogen, X is chloride and n is equal to 9; LASSBio-795 corresponds to the derivative of general formula (II) where R 1 corresponds to acetyl, R 2 is methyl, X is iodine and n is equal to 9; and LASSBio-783 corresponds to the derivative of general formula (III) where R 1 corresponds to acetyl, R 2 is hydrogen, X is chloride and n is equal to 9.
The following examples are for illustrative purpose only, not limiting the different ways of performing the invention.
EXAMPLE 1
Production and Structural Identification of the Natural Substrates Corresponding to General Formula (I)
The ethanolic extract of flowers and buds from C. spectabilis was concentrated, yielding 39.7 g of crude material, which was dissolved in a methanol-water 8:2 mixture. The mixture was submitted to ultra-sound and the insoluble residue, weighting 10.4 g, was removed via paper filtering. The hydroalcoholic solution was submitted to a liquid-liquid extraction, from which the following subfractions were obtained: hexane (2.0 g), dichloromethane (7.96 g), ethyl acetate (0.34 g), n-butanol (2.5 g) and aqueous (11.9 g).
A portion of the dichloromethane subfraction, weighting 3.25 g, was dissolved in 100 mL of chloroform, followed by successive extractions of 50 mL portions of 40% aqueous HCl, under magnetic stirring for 15 minutes each, making a total of 4 portions. The aqueous extracts were combined and alkalinized with concentrated aqueous solution of NH 4 OH up to pH 9-11, followed by successive extractions with chloroform (3×50 mL) and ethyl acetate (3×50 mL). The chloroform and ethyl acetate extracts were combined yielding 1.45 g of an alkaloidic mixture. This mixture was fractionated in chromatographic column with 44 g of neutral alumina as stationary phase. The alkaloidic mixture (1.45 g) was added followed by elution with a chloroform/hexane (9:1 to 9.5:0.5) mixture and by chloroform/methanol/hexane (8:0.5:1.5 up to 9:1:0) mixture, resulting in the production of 910 mg of a compound corresponding to general formula (I) when R is H (espectaline), and 151 mg of a compound corresponding to general formula (I) when R is acetyl (3-O-acetyl-ethyl espectaline).
The yield of this chromatographic procedure of espectaline was 28% from the dichloromethane subfraction, and 5% from the flowers and buds crude extract from of C. spectabilis , while the 3-O-acetyl-espectaline was obtained from the dichloromethane subfraction with 4.6% yield.
The compounds spectaline and 3-O-acetyl-espctaline had their chemical structures confirmed by polarimetric data, melting point and NMR spectrometric data of uni- and bi-dimensional 1 H and 13 C, infrared (IR) and mass spectrometry (MS). The espctaline was identified by comparison with laboratory available data, as being (−)-espectaline, and the 3-O-acetyl-espectaline was characterized as a natural derivative from espectaline, the (−)-3-O-acetyl-espectaline.
EXAMPLE 2
Production of Semi-Synthetic Derivates, Chlorhydrates, Corresponding to General Formula (II)
a) Synthetic approach to the preparation of 2-(R)-methyl-3-(R)—O-t-butoxycarbonyl-6-(S)-(tetradecyl-13′-one)-piperidine
To a solution of espectaline (0.5 g; 1.54 mmol) under N 2 atmosphere and in 15 mL of dry CH 2 Cl 2 , dry Et 3 N was added 0.3 mL (2.156 mmol), resting 5 min under stirring at room temperature. Afterwards, a solution of (Boc) 2 O (369 mg; 1.694 mmol) in 15 mL CH 2 Cl 2 was added and rested under stirring at room temperature for 24 h, being monitored by TLC. Then a catalytic amount of 4-DMAP and more 100 mg (Boc) 2 O were added, keeping the stirring under N 2 atmosphere for 4 more days.
After complete conversion of the starting material, 10 mL of water was added, followed by extraction with CHCl 3 (4×10 mL). The organic phases were then combined and washed with aq. HCl 2N (3×10 mL) followed by brine (2×10 mL). The organic phase was then dried with MgSO 4 , filtered and concentrated under reduced pressure.
The raw product was purified in neutral Al 2 O 3 column with CHCl 3 /Hex/MeOH as eluent to give 280.5 mg of the desired carbonate 3-O-Boc-espectaline together with the corresponding carbamate byproduct, in a 60% yield.
The reaction product was characterized by 1 H and 13 C NMR. The melting point of 3-O-Boc-espectaline derivative was 57.5-60° C.
b) Preparation of 2-(R)-methyl-3-(R)—O-acetyl-6-(S)-(tetradecyl-13′-one)-piperidine chlorhydrate (LASSBio-767)
In a single neck flask, 15 mg of 2-(R)-methyl-3-(R)—O-acetyl-6-(R)-(tetradecyl-13′-one)-piperidine (0.041 mmol) was dissolved in 3 mL of dry dichloromethane was dissolved. In a Keeper system conc. HCl was added and then conc. H 2 SO 4 was slowly added, letting the HCl (g) pass through the reaction system. The reaction was kept for 45 min., always adding dichloromethane to maintain the starting solvent level. At the end, the solvent evaporated, and a solid material was formed in the flask walls. This material was redissolved in dichlormethane and concentrated in a rotatory evaporator. LASSBio-767 was obtained in quantitative amounts and was characterized by 1 H and 13 C NMR, and through physical-chemical data. The water-soluble derivative presented melting point of 142.8-147.5° C.
The same experimental procedure was used for the preparation of espectaline chlorhydrate, which was obtained in quantitative amounts from the natural substrate, (−)-espectaline. Its characterization was made by 1 H and 13 C NMR and through physical-chemical data. The water-soluble derivative presented melting point of 149.1-151.1° C.
c) Synthetic Approach to the Production of Espectaline Chlorhydrate from 2-(R)-methyl-6-(S)-(tetradecyl-13′-one)-piperidin-3-(R)-ol (LASSBio-768)
In a single neck flask coupled with a reflux condenser, 375 mg (1.15 mmol) of 2-(R)-methyl-6-(S)-(tetradecyl-13′-one)-piperidin-3-(R)-ol was dissolved in 10 mL of ethyl acetate, followed by the addition of 4 mL fuming HCl. The reaction system was kept at room temperature for 10 h and under reflux for 4 h. At the end, the solvent was evaporated, the product was redissolved in methanol, dried with anhydrous MgSO 4 , filtered and solvent evaporated. After drying under vacuum, the compound LASSBio-768 was quantitatively obtained.
In a double neck flask coupled with a reflux condenser and under N 2 atmosphere, the compound LASSBio-767 (114 mg, 0.31 mmol) was dissolved in 5 mL of anhydrous chloroform. With the aid of a syringe, fresh distilled acetyl chloride (0.1 mL, 1.42 mmol) was added and let react during 12 h at 50° C. At the end, the solvent was evaporated and the remaining was dried under vacuum to obtain the compound LASSBio-767 with 93% yield.
d) Synthetic approach to the production of 2-(R)-methyl-3-(R)—O-ter-butoxycarbonyl-6-(S)-(tetradecyl-13′-one)-piperidine chlorhydrate (LASSBio-822)
The same experimental procedure described for the LASSBio-767 chlorhydrate production was used in the preparation of LASSBio-822 chlorhydrate from 3-O-Boc-espectaline. The derivative LASSBio-822 was obtained in quantitative amount and was characterized through 1 H and 13 C NMR. The water-soluble derivative LASSBio-822 presented melting point of 126-129.5° C.
e) Synthetic approach to the production of (2R,3R,6S)-3-acetoxy-6-(13-hydroxy-tetradecyl-2-methyl)-piperidine chlorhydrate (LASSBio-783)
The experimental procedure for the preparation of this derivative is based on a simple carbonyl reduction, through a number of reactions known by any technician in the area as, for example, the reaction of NaBH 4 in H 2 O at room temperature.
EXAMPLE 3
Pharmacological Evaluation
a) Anticholinesterasic Activity Assay
The anticholinesterasic effect of the compounds from the present invention is herein demonstrated, among other effects, by the results of the compounds LASSBio-767, LASSBio-768 and LASSBio-822. The compounds from the present invention were investigated in the brain tissue of rat, where the main form of the expressed enzyme, like in humans, is the tetramer of T type sub-unities, which are linked to membranes through hydrophobic chains (Boschetti, N.; Liao, J.; Brodbeck, U. The Membrane Form of Acetylcholinesterase From Rat Brain Contains a 20 KDa Hydrophobic Anchor. Neurochem. Res. 1994, 19, 359-365; Fernandez, H. L.; Moreno, R. D.; Inestrosa, N. C. Tetrameric (G4) Acetylcholinesterase: Structure, Localization, and Physiological Regulation. J. Neurochem. 1996, 66, 1335-1346). Ellman's calorimetric assay (Ellman, G. L.; Courtney, K. D.; Andres, V.; Featherstone, J.; Featherstone, R. M. A New and Rapid Colorimetric Determination of Acetylcholinesterase Activity. Biochem. Pharmacol. 1961, 7, 88-95) was adapted for determination of the total activity of cholinesterase in homogenized rat brain. Brain tissue of Wistar rats were homogenized in 2% v/v buffer sodium phosphate 0.1 M, pH 7.4, with the addition of NaCl 58.5 g/L and Triton X-100 0.05% v/v. Fractions of the homogenized mixture (20 μL) were incubated with the anticholinesterasic compounds for 10 minutes in pH 8 phosphate buffer before the addition of 5,5′-dithiobis(2-nitrobenzoic) acid and also of 1 mM of acetylthiocholine iodide (SIGMA, USA). The reaction was conducted at room temperature (22-25° C.), in 235 μL at microplates with 96 wells, followed by microplate reader (SpectraMAX 250, Molecular Devices, USA) at 412 nm during 5 minutes. In all experiments, cholinesterase-independent substrate hydrolysis (non specific) was determined by the inclusion of an experimental group treated with THA 20 μM. Appropriate tissues and reagents (em branco) were also included. Reaction velocities were determined in 3 or 4 repetitions by condition; mean values were calculated and expressed as percentages of relative activity in respect to control (solvent), after subtraction of the non-specific hydrolysis rate. The substances were tested in at least five different concentrations. From the resulting inhibition curve, values in the ranges outside 20%-80% were considered, with concentration limited to 500 μM. The IC 50 , based in a single-site model, was determined via linear regression. Results were expressed as Mean ±SEM of the IC 50 , obtained independently from 2 to 4 animals, and are presented in Table 1 below.
TABLE 1 Cerebral cholinesterase inhibition data. Compound Experimental IC 50 N Mean SD* SEM** Tacrine THA THA THA THA 4 0.16 0.05 0.03 (09/08/00) (10/08/00) (11/07/01)A (11/07/01)B 0.173433 0.224864 0.110992 0.112401 Galanthamine Gal Gal 2 3.10 0.26 0.18 (11/07/01)A (11/07/01)B 3.284665 2.923275 LASSBio 767 767 767 2 4.65 0.23 0.17 (22/11/01-r2) (29/11/01) 4.817214 4.486283 LASSBio 768 768 768 2 236.34 59.11 41.79 (22/11/01) (29/11/01) 194.541473 278.128845 LASSBio 783 783 783 783 3 425.56 243.49 140.58 (28/3/03-rA) (4/4/03-rB) (4/4/03-rC) 333.033844 701.750244 241.899277 LASSBio 795 795 795 795 3 243.48 76.73 44.30 (26/3/03-rA) (1/4/03-rB) (1/4/03-rC) 173.047897 232.144257 325.254974 LASSBio 822 822 822 822 3 15.08 5.45 3.14 (28/3/03-rA) (8/4/03-rB) (8/4/03-rC) 9.154104 16.217253 19.869019 *Standard Deviation. **Standard Error of the Mean.
b) Evaluation of the induced amnesia by scopolamine in the Morris Water Maze
A total of 39 Wistar rats (females−±200 g) were used. Animals were divided into experimental groups and respective control groups:
control=saline+saline−11 animals
saline+scopolamine (1 mg/kg)−8 animals
tacrine (1 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-767 (1 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-767 (3 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-767 (10 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-822 (1 mg/kg)+scopolamine (1 mg/kg)−4 animals
After 30 minutes of intraperitoneal second administration (saline or scopolamine), the animals were challenged to localize an underwater platform in a round recipient containing opaque water (water maze) and the escape latency (in seconds) was computed. If the animal did not locate the platform in 150 seconds, it was put in the platform for a 20 seconds period and then removed from the water. Tests were conducted twice a day, during 4 consecutive days.
As one could observe in FIGS. 1-4 , animals from the control group reduce significantly of the escape latency in the third and fourth days of the test. When treated with scopolamine 30 minutes before the challenge, the animals could not learn the task and the escape latency approaches maximum values (150 s) in the fourth day of the test. Results from the injection of the compositions are shown in FIGS. 1-4 .
The anticholinesterasic agent tacrine antagonize the induced amnesia by scopolamine, a significant effect in the fourth day of the study. The semi-synthetic alkaloid LASSBio-767 had a superior effect in relation to tacrine in the reversion of the induced amnesia by scopolamine, since the effect can be noticed in the second day of the treatment and is highly significant in the third and fourth days when the animals, although had received scopolamine (1 mg/kg), behave as the control group. The effect of the LASSBio-767 composition was also observed at 10 mg/kg concentrations. However, the LASSBio-822 alkaloid was not capable of antagonize the amnesia induced by scopolamine in rats in the water maze test.
c) Evaluation of the Amnesia Induced by Scopolamine in the Inhibitory Avoidance Assay
A total of 120 adult male (25-30 g) Swiss mice were used. The animals were submitted to the inhibitory avoidance assay, which consists of a box with a base made of a grid connected to an electrostimulator (0.6 mA/3s), and containing a wood platform (3 cm 3 ). Mice were put over this platform; being computed the latency (in seconds) until the animals put the four paws over the grid. In the first day of the test (“training”), animals would receive an adverse electrical stimulus (0.6 mA/3 s) whenever they stepped down to the grid (step down latency—SDL). At this stage, animals that would stay more than 15 seconds over the platform were discarded. Twenty-four hours later, the animals were re-introduced over the platform and the SDL computed (“retention”).
Mice were divided into six experimental groups:
control=saline+saline
saline+scopolamine (1 mg/kg)
LASSBio-767 (1 mg/kg)+scopolamine (1 mg/kg)
LASSBio-767 (10 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-822 (1 mg/kg)+scopolamine (1 mg/kg)−4 animals
LASSBio-822 (3 mg/kg)+scopolamine (1 mg/kg)−4 animals
It was observed that the alkaloid LASSBio-767, in both concentrations, did not present any effect on the amnesia induced by scopolamine. However, in this assay, the semi-synthetic alkaloid LASSBio-822 was capable of a significant reversion of the amnesia induced by scopolamine. In this assay, tacrine has totally reversed the effect of scopolamine. Results from this assay can be seen in FIGS. 5-7 .
d) Evaluation of Cholinergic Side Effects Induced by Tacrine and LASSBio-767
Past 10 and 30 minutes after the I.P. administration of the drugs, the animals (n=10 mice/group) were observed in respect to the psicomotor activity in the open field test, lateral projection of rear paws, shivering, salivation, lachrymation, diarrhea, urination, and hypothermia. It was also verified the tacrine concentration capable of leading 50% of the animals to obit (LD50).
After the administration of tacrine (10 mg/kg), diarrhea and urination were observed in 70% of the mice. Moreover, this concentration of tacrine resulted in hypothermia and diminished motor activity. After administration of tacrine in concentrations superior to 30 mg/kg, all checked parameters are altered.
Apart from mice, rats were observed after 30 minutes from administration of tacrine at 1 mg/kg (n=4), LASSBio-767 (n=12) and saline (n=12) and saline (n=12). Only animals treated with tacrine presented diarrhea after 30 minutes from administration and this symptom was observed in 100% of the animals.
Results from this assay can be seen in FIGS. 8-9 . LASSBio-767 and LASSBio-822, at lower concentrations when compared to tacrine, were capable of reversing the amnesia induced by scopolamine in different models of learning and memory. On the other hand, no cholinergic side effects and no interference in the motor activity were observed with LASSBio-767 (10 mg/kg), which was observed with tacrine. In our studies, the therapeutic window of tacrine has proved to be too narrow. These results suggest a promising role of the studied compounds in the Alzheimer Disease therapeutics and in other pathologies associated to memory deficiency conditions. These compounds seem to have a superior efficacy and safety in comparison to drugs in clinically used today.
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Pharmaceutical compositions containing new molecules capable of inhibiting acetylcholinesterase, thus being useful in the treatment of pathologies associated to cholinergic transmission, such as memory related disorders, neurodegenerative disorders such as Alzheimer's Disease, Miasthenia Gravis or in the treatment of intoxications induced by chemical agents of central action The production processes of pharmaceutical compositions.
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FIELD OF THE INVENTION
This is related to the field of electrical connectors and more particularly to connectors for use with electrical wires.
BACKGROUND OF THE INVENTION
The telecommunications industry utilizes a variety of electrical connectors in several different situations in which electrical connections must be made. One such situation is the providing of electrical connections between a telephone cable and a service cable at an individual customer site, mainly through use of a splice of the tip and ring signal wires of a drop wire from the main cable to respective house wires of the service cable at a junction located outside or inside the house. Ends of both the drop wire and the service cable enter an enclosure, and the tip and ring wires of each are interconnected or spliced to the tip and ring wires of the other in a terminal block, commonly termed a crossconnect block. Such a crossconnect block must not only provide dielectric protective structure around the splice, but together with the enclosure must provide protection from the environment, especially from water, dust, and other contaminants and also from insects and animals. Such enclosures must be capable of being reopened to expose the crossconnect blocks and other electrical connectors therein for service and repair as needed. Also, certain terminal blocks are utilized to provide protection of the individual circuits from voltage and current surges for safety reasons and for the protection of sensitive electrical and electronic equipment from damage.
One such crossconnect block is disclosed in U.S. Pat. No. 5,219,302. A dielectric housing includes a pair of tubular terminal-receiving housing sections each with an integrally molded center post therewithin extending upwardly from a common base section, thus defining an annular cavity within which is disposed a barrel-shaped terminal and a tubular actuator adapted to rotate the terminal from an unterminated position to a terminated position. Each housing section is provided with a pair of wire-receiving openings through side walls and into the cavity aligned with an aperture through the center post, and associated openings are provided in contact sections of the terminal and in the actuator that are aligned with the side wall openings when the terminal and actuator are ill the unactuated position. Slot walls of the terminal extend circumferentially from each wire-receiving opening and are precisely profiled to include constricted edges to penetrate the wire insulation and assuredly engage the conductor therewithin. During splicing, the wire ends of both tip wires (or both ring wires) are inserted into respective openings of the same housing section and through the apertured contact sections of the terminal and into the center post until stopped by abutment against a stop surface. Upon rotation of the rotatable terminal by the actuator such as through a quarter turn, slot walls of the terminal pierce the insulation of the respective wires and engage the respective conductors thereof, thus commoning and interconnecting them.
U.S. Pat. Nos. 5,317,474 and 5,321,577 both disclose a similar terminal block in which is contained one or two surge-protecting electrical components or protectors. The circuits of the wires terminated within the terminal block are provided-with protection against voltage and current surges by the protectors. Both terminal blocks utilize similar housing structure and terminals and actuators for the insulation displacement termination of unstripped wires as in U.S. Pat. No. 5,219,302.
In U.S. Pat. No. 5,219,302 and also in U.S. Pat. No. 5,006,077, such terminal blocks with rotatable terminals in annular housing cavities are adapted to accommodate wires of two particular sizes. While wire entrance apertures of the housing section sidewalls are wide enough to receive a larger 18 AWG size wire therethrough, the wire-receiving passageways of the center post are profiled to receive and stop the end of the 18 AWG wire at a tapered transition section located between the larger diameter forward passageway portion and a smaller diameter passageway portion. The tapered transition portion acts as a lead-in to prevent stubbing, to permit the end of a smaller 24 AWG wire to pass completely through and exit from the center post and continue therebeyond (and through apertures in the terminal and actuator) until stopped by a stop recess in the far annular cavity sidewall opposed from the wire entrance apertures. When the smaller diameter wire is thus extended completely through and beyond the center post, the far portion of the terminal through which the free end of the wire extends is provided with a smaller diameter slot to assuredly engage the smaller diameter conductor within the 24 AWG wire; the larger diameter slot adjacent the wire entrance is useful in biting into the insulation and establishing a strain relief protecting the termination from forces otherwise transmittable to the end of wire.
Quiet Front crossconnect and protected terminal blocks are sold commercially by AMP Incorporated and contain sealant material that embeds the terminal in each housing cavity (and the protector component, if any) and also embeds the end of each wire inserted into and terminated by the terminal block. Such sealant material is preferably gel-like and may be as disclosed in U.S. patent application Ser. No. 07/955,535 filed Oct. 1, 1992 and also may be one of several materials disclosed in European Pat. Publication No. 0 529 957 A1. It is common that regarding very small gage wires, once a wire end has been inserted into the housing section and then released to manually rotate the actuator for actuation of the terminal for termination to the wire end, such material, especially material of gel-like consistency tends to urge the inserted wire end at least partially out of the housing. Thus it is possible that the free end of the wire may be moved sufficiently toward the wire entrance that it no longer resides in the wire end recess of the cavity sidewall and may not become terminated upon rotation of the terminal.
It is desired to provide a terminal block filled with sealant material such as gel-like material, that permits an indication that the wire end is fully inserted.
It is desired to provide a terminal block filled with sealant material such as gel-like material, that assures that the wire end remains fully within the terminal block after insertion but prior to termination.
SUMMARY OF THE INVENTION
The present invention provides a means for enabling verification that the free end of a wire inserted into a terminal block remains fully inserted once released in order to actuate the actuator. Such verification is by visual inspection permitted by a wiring indicator provided along the outer surface of the housing section, formed of transparent material such as thermoplastic resin and including a wire-receiving cavity aligned with each wire-receiving aperture of the housing section and diametrically opposed therefrom and in communication with the annular cavity aligned with the wire passageway of the center post. Such wiring indicator may be a separate article molded and secured to the terminal block, such as by being latched thereto. Preferably the wiring indicator includes chambers defining wire-receiving cavities associated with all wire-receiving apertures of the terminal block, where all such apertures are along a common face of the terminal block and the wiring indicator is applicable to the opposed face of the terminal block. Preferably the sealant material is also transparent so that even when the wire-receiving cavities of the wiring indicator is also sealant-filled, the wire end is visible when fully inserted.
In another aspect of the present invention, a biasing means is provided in the terminal block engageable with the free end of a wire inserted into the terminal block upon full insertion through the aligned wire-receiving apertures of the housing section, terminal and actuator. Such biasing means may be a spring member secured within the terminal block along the face thereof opposed from the wire-receiving face. Alternatively the biasing means may be a clip securable about the terminal block with wire-retention sections adjacent the wire-receiving entrances, comprising a pair of spaced converging tabs extending toward the entrances deflected apart as a wire is urged between them and into the entrance.
Preferably the biasing means or wire retainer is secured within the wiring indicator member. In one embodiment of such an arrangement, one end of the wire retainer is secured to the assembly and a free end extends into the wire-receiving cavity angled across the insertion path for the wire. The free end is thus cantilevered and is deflectable against spring bias by the free end of the wire upon full insertion. The spring bias applied against the wire free end urges it against the far wall of the wire-receiving cavity and is sufficient to retain the wire free end within the cavity against the forces of the sealant material tending to urge the wire rearwardly along the insertion path and toward the wire-receiving entrance.
In one embodiment where the wiring indicator includes vertically aligned wire-receiving cavities (or a single large cavity) associated with an adjacent pair of wire-receiving entrances of a single housing section, a single wire retainer can include a pair of cantilever spring arms extending from a common body section secured within the wiring indicator, such that each cantilever spring arm traverses a respective wire insertion path and is deflectable by a respective wire free end.
It is one primary objective of the present invention to provide a means for verifying that the free end of a wire once inserted into a terminal block but prior to its termination, remains fully inserted thus assuring appropriate termination upon actuation of the terminal.
It is also an objective that such a wiring indicator result in a sealed terminal block.
It is a further objective to provide such a wiring indicator as a separate article easily securable to a terminal block.
It is a second primary objective of the present invention to provide a means for assuredly maintaining full insertion of a wire end once inserted into a terminal block and released, prior to termination.
It is an additional objective to provide a complementary arrangement of wiring indicator and wire retainer that both retains the wire fully inserted and enables verification of that full wire insertion condition, prior to and after termination.
Embodiments of the present inventions will now be disclosed by way of example with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a terminal block having the wiring indicator of the present invention assembled thereto, with a pair of wires inserted thereinto for termination and splicing for interconnection to each other and an additional pair of wires about to be inserted thereinto for termination;
FIG. 2 is an isometric exploded view of the terminal block of FIG. 1 also showing a pair of wire retainers contained in the assembly;
FIG. 3 is a plan view of the terminal block of FIGS. 1 and 2 with the wiring indicator and a wire retainer about to be assembled to the housing;
FIG. 4 is a cross-sectional view of the terminal block of FIG. 1 showing one wire fully inserted for termination and entered into the wiring indicator and engaged by the wire retainer of the present invention; and
FIGS. 5 to 7 illustrate an alternate embodiment of wire retainer, with FIG. 5 being an isometric view of the clip, FIG. 6 being an isometric view of the clip affixed about a terminal block housing, and FIG. 7 being an illustration of alternate wire-retention section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 is shown a protected terminal block 10 having a housing assembly 12 including a pair of generally cylindrical housing sections 14 each having therewithin an annular cavity containing a barrel-shaped terminal and an actuator 16 therefor. A bottom cover 18 contains a protector unit (not shown) having leads electrically engaged with the respective terminals and also electrically connected to a ground contact section 18 seen extending from the assembly for connection to a system ground and also enabling mounting of the terminal block within an enclosure (not shown). Such a terminal block is disclosed with greater particularity in U.S. Pat. No. 5,317,474.
Each housing section 14 includes a pair of wire-receiving entrances 22,24 associated with respective wires 26,28 that are to be spliced or crossconnected to each other by the terminal within the housing section upon actuation, preferably with the wire-receiving entrances 22,24 of both housing sections being disposed along a common wire-receiving face 30 of the terminal block. Preferably contained within annular cavities of housing sections 14 is a sealant material, preferably gel-like, such as is disclosed in European Pat. Publication 0 529 957 A1 for example, a mixture of an elastomeric thermoplastic polymer such as a composite of diblock and triblock copolymers, and an extender such as a mixture of mineral oil and polyisobutene, and also may include silica and another polymer crosslinked with the elastomeric polymer. The sealant preferably contains corrosion inhibitors and suitable stabilizers such as antioxidants, and also preferably has memory properties, being able to absorb energy on being deformed and to return to its original state upon removal of the source of stress. Also, a tape element (not shown) may be adhered across wire-receiving face 30 of housing 12 with small apertures aligned with larger wire-receiving entrances 22,24 as is disclosed in U.S. patent application Ser. No. 07/955,535 filed Oct. 1, 1992.
Referring now to FIGS. 1 to 4, along rear face 32 is defined a wiring indicator, shown as a separate member 60 and having latch arms 62 coextending at opposed ends forwardly from body section 64 to free ends 66 on which are defined inwardly facing latching projections 68. Protruding rearwardly from body section are chambers 70 that when member 60 is affixed to rear face 32 of the assembly, are aligned with respective ones of wire-receiving entrances 22,24. Wire-receiving cavities 72 extend into chambers 70 from forward face 74, and forward portions 76 of walls surrounding the entrances to cavities 72 are adapted to enter into complementary recesses 34 of outer surface portions of housing 12 surrounding wire exits 36 (FIG. 4) upon latching of element 60 thereto with latch projections 68 latching onto forwardly facing latch surfaces 34 defined by housing 12. Wiring indicator element 60 is preferably transparent to enable visual inspection thereinto for verification of the receipt of wire ends into wire-receiving cavities 72 of chambers 70.
Also seen in FIGS. 1 to 4 are wire retainers 90 that are disposed along forward face 74 of element 60, with body sections 92 insertable into slots 78 into forward face 74 of body section 64. Spring arms 94 are joined to body section 92 of each wire retainer 90, extending first forwardly therefrom and then partially bent back at hinges 96 to conclude at free ends 98. Upon mounting of body section 92 into a respective slot 78, spring arms 94 are disposed within respective ones of cavities 72 of chambers 70 of element 60. Preferably free ends 98 are adapted to be spring biased against the far side wall 80 of the respective cavities upon assembly and are adapted to be deflectable toward the near side wall 82 pivotable about hinges 96, as is more clearly seen in FIG. 4.
Referring to FIG. 4, the left housing section 14 of terminal block 10 is shown prior to insertion of a wire end thereinto, and the right housing section is shown following full insertion of an end portion of a wire 26 thereinto. Barrel-shaped terminals 40 are shown disposed in annular terminal-receiving cavities 42 of the housing sections around center posts 44. Terminal-engaging actuator section 46 is seen in annular cavity 42 disposed around the terminal, as disclosed in U.S. Pat. No. 5,219,304 and is adapted to engage and rotate clockwise the terminal upon actuation. A wire 26 is shown inserted into wire-receiving entrance 22, through first aperture 48 of terminal 40, through passageway 50 of center post 44, through second aperture 52 of terminal 40 and outwardly through wire exit 36.
Free end 54 of wire 26 is received into a respective wire-receiving cavity 72 of a chamber 70 of element 60, and is shown to have engaged and deflected spring arm 94 of wire retainer 90. As is shown, spring arm 94 possesses sufficient spring strength to urge free end 54 of wire 26 against far side wall 80 and preferably includes a sharp corner to tend to bite into the insulative covering of wire 26 whenever wire 26 is urged by the sealant material in housing section 14 backwardly toward wire-receiving entrance 22 thus resisting the pullout force applied by the sealant. However, it is desirable that the spring strength not be so great as to prevent intentional withdrawal of the wire for repair or replacement. Were wire 26 to be withdrawn for repair or replacement, wire retainer 90 would remain in place to reengage a wire end subsequently urged through the terminal block and into cavity 72 for retermination.
Upon actuation of terminal 40 by the actuator (FIG. 1), the terminal is rotated clockwise, with first slot 56 being urged past wire 26 adjacent first wire-receiving aperture 48 at wire-receiving entrance 22 and penetrating the insulation of the wire, and second slot 58 being urged past wire 26 adjacent second wire-receiving aperture 52 adjacent wire exit 36 and penetrating the wire insulation and also engaging the conductor therewithin. If desired, terminal 40 can be rotated counterclockwise to unterminate the wire allowing wire 26 to be withdrawn and later reinserted and reterminated, or a new wire inserted and terminated.
Wiring indicator element 60 preferably is molded of thermoplastic material and may for example be molded of polyphenylsulphone such as RADEL R-5000 sold by Amoco Performance Products, Inc. Wire retainer 90 may be molded of thermoplastic material and may for example be molded of polycarbonate resin or such as amorphous thermoplastic such as ULTEM 1000 polyetherimide sold by General Electric Company. Alternatively, such a wire retainer could be made of phosphor bronze, for example.
Alternatively, as seen in FIGS. 5 to 7, the biasing means may be a clip 100 securable about the terminal block 102 with wire-retention sections 104 adjacent the wire-receiving entrances 106, comprising a pair of spaced converging tabs 108 extending toward the entrances and defining a constriction 110 at or proximate free ends 112, with the tabs being deflected apart as a wire is urged between them, through constriction 110 and into the entrance 106. Constriction 110 would be selected to be less than a nominal wire diameter, and is capable of being used with larger size wires if necessary, since tabs 108 are deflectable apart. In clip 100, only two wire-retention sections 104 are illustrated, although additional similar sections could be provided for the upper pair of entrances 114; however, with the lower wire 116 being retained by the clip, the upper wire 118 being spliced or interconnected therewith could be manually held in place while the actuator is actuated for termination, as the upper and lower pairs of wires are terminated in sequence. Fastening of the slip to the terminal block housing could be accomplished such as by a latch projection 116 latchable into a complementary recess (not shown) into the outer surface of the housing. Such a wire-retention clip could be molded of plastic such as of polyphenylsulphone.
Wire-retention portion of the clip may also be a slot 130 such as is shown in FIG. 7 having a dimension slightly less than a nominal wire diameter, so that when a wire has been fully inserted into the wire-receiving aperture it may be pressed into slot 130 and thereafter be held therein in interference fit.
Variations and modifications may occur departing in detail from the specific embodiments and examples disclosed herein, that are within the spirit of the inventions and the scope of the claims.
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An electrical connector (10) including a housing (12) with a pair of housing sections (14) each containing a terminal (40) rotatable therewithin upon actuation to terminate an end of a wire (26,28) inserted into an aperture (22,24) thereof. For small diameter wires, a wiring indicator (60) of transparent material is affixed to the opposed side of the housing and includes a chamber (70) for each wire to be extended therethrough for termination, thus enabling visual verification that a wire end has been fully inserted. A wire retainer (90,100) is used to prevent inadvertent backout after full wire insertion but before termination. Wire retainer (100) can be a clip mountable outside the housing, and wire retainer (90) can be contained in the wiring indicator includes a spring arm (92) biasing against the wire free end (52) upon full insertion.
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BACKGROUND OF INVENTION
[0001] 1. Field of The Invention
[0002] This invention pertains to wind mill blades that are for mounting onto an axle to turn in a wind and produce a power output for doing work, with the combination of the blade design and a nose cone directing an air flow into the blades providing a very efficient conversion of the wind energy into blade turning.
[0003] 2. Prior Art
[0004] The present invention is in a new and substantially more efficient wind powered blade structure than any presently available wind mill blade or blades arrangement. Specifically, the present invention is an improvement over an earlier wind sail receptor that the inventor is a joint inventor of, set out in U.S. Pat. No. 7,309,213. Unique to the invention, the blades of the improved wind sail receptor are formed separately as flat segments for mounting between rear and forward hubs, forming a wind sail receptor having three to five blades, depending upon the diameter of the hub the blades are mounted to. The individual blades are each bent between forward and rear hubs to have a leading edge from the forward hub that faces into the wind, and are curved across a cylinder whose ends the forward and rear hubs are mounted to, forming a blade trailing edge. The blades are bent between the leading and trailing edges in a uniform arc and provides a smooth turbulence free wind transition where the wind flow exits off the blades trailing edges at approximately a forty five degree angle downwardly to the direction the entering wind. Which wind flow redirection turns the wind sail receptor blades that are mounted on an axle that turns a generator.
[0005] The spacing of the blades around the hub and the bend angle of each blade provides, in practice, for a maximum utilization of the force of the entering wind to translate that wind force into wind sail receptor turning. Further, to provide a maximum efficiency in the utilization of the energy of the wind flow into the wind sail receptor, the invention includes a nose cone, that is fitted over a forward end of a wind sail receptor housing. Which nose cone has a cylindrical shape and slopes outwardly from a rounded dome end to an open base end that mounts across the front or wind facing end of the housing and contains a generator that is axially connected to be turned by wind sail receptor turning, with the wind sail receptor journaled to turn freely on the housing rear end. Which nose cone slope and the radius of the rounded dome end are selected to provide for a translation of wind striking the nose cone and direct it over the rounded top end and along a nose cone cylindrical section, and along the housing surface and into the wind sail receptor blades to turn the wind sail receptor blades, without a creation of turbulence in the wind flow entering the wind sail receptor.
[0006] A wind flow passing over the nose cone travels along the housing, that is pivot mounted to the top of a vertical pole, and into the wind sail receptor blades that are thereby turned into that wind flow, without a necessity for a rudder, or like device to turn the wind sail receptor into the wind, causing the wind sail blades to always face directly into the wind flow.
[0007] So arranged, the combination of the unique blade design and arrangement of the nose cone provide for an essentially turbulence free passage of a wind flow through the wind sail receptor to capture most, if not all of that wind flow energy, and convert it into torque turning the wind sail receptor blades that are axially connected to turn the generator contained in the housing.
[0008] Heretofore, wind mill blade configurations have generally lack efficiency, particularly the blades as are turned in a wind farm operation, that operate at only an efficiency of approximately twenty (20), and thereby utilize only a small percentage of the energy of a wind energy passing through the blades. Which wind farm blades, therefore, have to be large to produce a worthwhile energy output. In fact, even the wind sail receptor of applicant's prior patent could only obtain an efficiency of approximately ninety (90) per cent utilization of wind energy at winds of from eight (8) to ten (10) miles per hour and greater.
[0009] The wind sail receptor blades arrangement, because of its size, manner of construction and assembly is far less expensive to construct and maintain over earlier and present wind mills, and is therefore a significant improvement over earlier wind powered systems.
SUMMARY OF THE INVENTION
[0010] It is a principal object of the present invention to provide a wind sail receptor for converting wind power into torque that is applied through an axle of the wind sail receptor to turn a generator for producing electrical energy, whose design provides for a very efficient use of wind energy for turning of the wind sail receptor blades that nears a one hundred percent efficiency.
[0011] Another object of the present invention is to provide a wind sail receptor having three to five blades, dependent upon the diameter of the blades hubs, and can be arranged to form six, twelve and up to twenty five foot diameter assemblies that will be significantly smaller in diameter than other wind mill arrangements that produce a like or lesser power output, as compared to the invention.
[0012] Still another object of the present invention is to provide a wind sail receptor where the blades are preferably formed and shipped flat for later installation onto a hub arrangement that, accordingly, are inexpensive to manufacture and ship, and can be easily installed and repaired on site.
[0013] The present invention is in a wind sail receptor for converting wind energy into electrical power that has three to five blades, depending upon the diameter of forward and rear blade hubs, that can be formed into six, twelve and up to twenty five foot diameter assemblies. In which assemblies, the blades are equally spaced around a rear hub, and are each bent from attachment points at the front face of the rear hub to a forward location on a cylinder, that is proximate to the forward hub, where the rear and a forward hub are connected to opposite faces of the cylinder. Which blade to rear hub connection is at spaced points around the rear hub front face, and the connection to the cylinder is to at least one, and may be to several aligned spaced attachment tabs, that extend outwardly from the cylinder surface, with a forward most connection point being adjacent to the forward hub. In which blade mounting the blade is bent in a uniform curve from leading to trailing edges. Which bend has a uniform curved surface that a wind flow entering the wind sail receptor will travel over from the blade leading to trailing edges, without a creation of turbulence in that wind passage. Which wind flow will exit off of each blade trailing edge at approximately a forty five degree angle to the entering wind flow, without a creation of wind flow separation or turbulence in that exhaust flow as it passes off the blade trailing edge.
[0014] The wind sail receptor of the invention includes a nose cone that is secured across a forward end of a housing that has the forward hub mounted to turn freely on the cylinder rear end. Which nose cone has a dome shaped outer end surface and a cylindrical body that connects at a rear surface of the forward end of the housing. The nose cone is formed to provide an even distribution of a wind flow that strikes and travels along the housing, to pass to the forward hub, and travels into the blades. Which wind flow, absent the nose cone, would strike a blunt forward end of the housing and spread outwardly into the wind flow entering the wind sail receptor, negatively affecting wind sail receptor turning efficiency.
[0015] The blades of the wind sail receptor are preferably formed individually and each has an inner end attached at forward spaced points to a front surface of the rear hub, and is bent therefrom forward along the outer surface of a cylinder to a point thereof that is proximate to the forward hub. From the rear hub attachment, each blade cylinder mounting end is bent along the cylinder outer surface to a forward attachment tab that is adjacent to the forward hub for attaching the blade to butt against the cylinder outer surface. In which blade to cylinder mounting the blade is bent into an arc of from seventy to seventy eight degrees that provides for a smooth redirection of the entering wind flow that has passed across the nose cone and traveled along the housing, to turn the wind sail receptor blades, translating wind energy into wind sail receptor turning.
[0016] Each blade from a second connection to the rear hub has an outwardly curved edge that is the blade trailing edge and is curved from its first inner end connection to fit closely to the cylinder surface and ends in a connection end that couples to a tab that extends outwardly from the cylinder surface, proximate to the front hub and the cylinder end of the blade leading edge. Which blade forward trailing and leading edges, respectively, extend outwardly from the cylinder, and each connects to an opposite end of a straight blade outer end. The blade leading edge, before mounting, is essentially straight. However, when bent, appears to have a curved leading edge, and the trailing edge that is curved outwardly adjacent to the rear hub mounting to a point therealong wherefrom it is essentially straight to is end connection to the blade outer end.
[0017] In operation, a wind flow entering the wind sail receptor from the nose cone and across the housing travels over blade essentially straight sloping leading, and is redirected by the blade trailing edge curved section as a smooth non turbulent flow to the blade trailing edge. Which wind flow has passed off of the nose cone and along the housing as a smooth air flow that then travels across the blades leading edge, around the curve of the blades, and exits off of the blades trailing edges as a turbulence free air flow. Which exhaust wind flow is directed downwardly by the blades trailing edges of each blade at approximately a forty five degree angle to the entering wind flow. Which exhaust air flow is turbulence free and provides nearly a one hundred percent efficiency in the conversion of the entering wind flow energy into turning of the wind sail receptor. With the redirection of the entering air flow redirection acting on each blade to translate the wind flow energy into blade movement that turns an axle that is axially connected to the hubs to turn a generator mounted in the housing, converting the energy of the wind flowing into the wind sail receptor into axial torque.
[0018] The blade themselves and the other components of the wind sail receptor of the invention are simple and economical to produce, with the blades, preferably manufactured by casting methods, from a polyurethane material and are connected to the rear hub to be equally spaced there around.
[0019] In operation, the wind directed across the nose cone and along the housing acts on the wind sail receptor blades to pivot the housing with wind direction changes such that the wind sail receptor will always face into the wind.
DESCRIPTION OF THE DRAWINGS
[0020] The invention may take physical form in certain parts and arrangement of parts, and a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof:
[0021] FIG. 1 shows a profile perspective view taken from a right side and rear end of a four-blade wind sail receptor of the invention and shows a nose cone fitted over a front end of a housing that is pivot mounted onto a top end of a pole;
[0022] FIG. 2 shows a top plan view of a single blade of the wind sail receptor showing the blade as flat and includes blade leading and trailing edges, with a blade outer end connected to the ends of the leading and trailing edges, showing the blade leading edge end as having a radius to fit to a forward face of a rear hub that has end holes formed therethrough that connect to the rear hub forward face, and shows a blade leading edge lower end as including a hole that connects to a connecting tab that extends outwardly from the surface of a cylinder, adjacent to a forward hub rear end, and shows the blade leading edge end bent from the connection to the attitude shown in FIG. 1 ;
[0023] FIG. 3 shows the flat blade of FIG. 2 connected to the front face of the rear hub and is bent from its leading edge at to its connection to the cylinder surface, proximate to the forward hub;
[0024] FIG. 4 is a front profile perspective view of the wind sail receptor of FIG. 1 , showing the curvature of each blade from leading to trailing edge bent at an angle of 70 to 78 degrees, and shows the nose cone mounted to a housing forward end;
[0025] FIG. 5 is a profile perspective view like that of FIG. 1 taken from the rear face of the rear hub connected to rear end of the housing and includes a nose cone installed over the housing forward end, which nose cone has a dome shaped forward end and has a cylindrical body with the surface of that cylinder tapering from a lesser to greater diameter end and is connected to the housing forward end, and shows a wind flow, arrow B, striking the cone nose end that separates and travels down the nose cone sides and into a wind flow A that travels into the blades, showing the joined flows as combining and traveling into the blades;
[0026] FIG. 6 is a side elevation view of the nose cone of FIG. 5 , showing the nose cone dome radius and the taper of the cylindrical sides from lesser to greater diameters, and shows, as broken arrows B, the wind flow traveling over the dome end and along the nose cone cylindrical body, and shows the nose cone rear end as including threads;
[0027] FIG. 6A is a side sectional view of an alternative nose cone connection arrangement that includes a step formed around the housing front end edge whereover the nose cone is fitted and is secured thereto as with screws;
[0028] FIG. 7 shows a side elevation view of the wind sail receptor body as a cylinder with attached rear and forward hubs, and shows the rear hub attached to the cylinder rear end with fasteners fitted through spaced holes, less blades, and shows the forward hub journaled to the housing rear end to turn freely, and which housing is shown as pivot mounted to a top end of a pole, so as to allow the wind sail receptor to track into the wind flow; and
[0029] FIG. 8 shows the wind sail receptor body of FIG. 7 , that includes the wind sail receptor blades mounted thereto, with wind flows A and B, shown in broken lines, into the wind sail receptor from the nose cone.
DETAILED DESCRIPTION
[0030] The present invention is in a wind sail receptor 10 , shown in FIGS. 1 , 3 through 5 and 8 , having from three to five blades 11 that are spaced at equal distances around a rear hub 12 , where the rear hub 12 diameter is selected to accommodate the chosen number of blades and includes spaced holes 12 a appropriate to the number of blades that are attached to a front face of the rear hub, and a preferred four bladed wind sail receptor 10 is shown in FIGS. 1 and 3 through 5 . Which Figs. show the like blades 11 attached at equal intervals around the front edge of the rear hub 12 , and show the combination of the blades 11 arranged in close spaced proximity to one another and are attached at hub connection ends 15 to the front surface of the rear hub 12 .
[0031] FIG. 2 shows a flat plane view of a preferred blade 11 that is configured to have a curved rear hub connection section 15 that is for attachment, at first and second connection holes 15 a and 15 b , respectively, to the rear hub 12 front surface, as shown in FIGS. 1 and 3 . The blade 11 is shown as having a curved section 16 , adjacent to its second connection 15 b, that extends to a forward hub 18 connection end 17 and has a connection hole 17 a formed therein. Which curved section 16 is formed to conform to the surface of a cylinder 26 that the rear and forward hubs, 12 and 18 , respectively, are connected to. Shown in FIG. 2 , the blade 11 curved section 15 includes the first and second connection holes 15 a and 15 b that are proximate to the ends of the arc of the circumference of the rear hub 12 that receive fasteners, such as screws or bolts, that are turned into holes 12 a formed through the rear hub 12 , shown in FIGS. 1 and 3 , for fastening the blade arc section 15 to the forward face of the rear hub 12 .
[0032] The blade 11 is thereby connected to the rear hub 12 forward face at its arc section 15 by fitting fasteners, such as screws, through the first and second rear hub connection holes 15 a and 15 b , respectively, into selected rear hub holes 12 a. With the blade 11 connected to the rear hub 12 , a trailing blade edge 23 is adjacent to the second connecting hole 15 b and extends outwardly therefrom. The blade 11 has a curved section 16 that extends from adjacent to the first connecting hole that is for fitting closely to the surface of a cylinder 26 , as shown in FIGS. 3 and 8 , and terminates in an end 17 that has a connecting hole 17 a formed therethrough. Which hole is for alignment with and connection to a tab 27 that projects outwardly from the cylinder surface and is adjacent to a rear surface of forward hub. With the connection of the blade 11 end 17 to the tab 27 , the blade curved section 16 will fit closely to the cylinder 26 surface, as shown in FIGS. 4 and 8 . With that coupling of the blade end 17 to the tab 26 , as shown in FIGS. 4 and 8 , the blade 11 is bent into a smooth arc, as discussed below, and a blade leading edge 19 extends outwardly from the cylinder 26 , as shown in FIGS. 1 , 3 , through 5 and 8 . So arranged, the blade leading edge and trailing edges 19 and 23 , respectively, extend outwardly from the cylinder 26 , and each connects to an end of a straight blade end 21 .
[0033] The curve of the blade inner surface 16 is, of course, dependant upon the diameter of the rear and front hubs, 12 and 18 , respectively, and the cylinder 26 , and that curve is dependent upon the number of blades 11 , whether three to five blades 11 are employed, and the diameter the wind sail receptor 10 across the blades. Also, as shown in FIG. 2 , to accommodate the different diameter of hubs and cylinder, the arc section 15 of the blade inner end between the first and second rear hub mounting holes 15 a and 15 b, is selected to fit snugly to the rear hub 12 and cylinder 26 , at connection points 12 a.
[0034] The blade 11 is bent between the front face of the rear hub 12 to its end connection point 17 a and it's coupling at a hole 28 in an end of tab 27 , that extends outward from the cylinder 26 surface, into an arc of from seventy to seventy six degrees, whereby a wind striking the blade 11 leading edge 19 will travel, without turbulence, around the blade arc to exit, without turbulence, off of the blade trailing edge 23 .
[0035] Where a blade 11 single end connection point 17 a is shown for connection to the coupling to the single tab 27 , it should be understood that additional spaced coupling tabs 27 can be installed onto the cylinder 26 surface, and appropriately spaced holes can be formed along the blade inner surface section 16 that align with to connect to the spaced tabs 27 , to provide a reinforcement of the connection of the blade inner surface 16 to the cylinder 26 surface. Such reinforcement, while not required, is useful for adding strength to the blade to cylinder connection, particularly for the twelve and twenty five foot diameter wind sail receptors. Which tab 27 and blade 17 end connection, as shown in FIG. 8 , is adjacent to the rear surface of the forward hub 18 , as shown in FIGS. 1 and 3 .
[0036] Shown in FIG. 2 , the blade 11 has a sloped front side 19 that terminates in a front tip end 20 , which tip end connects to a straight blade end 21 , whose opposite end 22 connects to an outer end of blade 11 trailing edge 23 , whose opposite end connects to the blade arc section 15 , proximate to the hole 15 b. Which blade trailing edge 23 , as shown in FIG. 2 , is curved outwardly at section 24 at an arc of approximately fifteen (15) degrees from its junction with the arc section 15 , end, adjacent to hole 15 b, with that curve reversed at a distance from the blade trailing edge end 22 that is approximately one fourth to one third the distance from the blade hole 15 a to the blade trailing edge end 22 into an inward arc of approximately ten (10) to twenty (20) degrees at a junction 24 a to the blade end at 22 . So arranged, with the blade 11 attached at connection point 17 a to the cylinder 26 , at tab 27 , that is located proximate to a rear face of the in front hub 18 , as shown in FIG. 3 , the blade 11 will curve from its leading edge 19 to its trailing edge 23 , as shown in FIG. 4 . With, as shown in FIG. 4 , the blades 11 are bent into a smooth curve or arc of from seventy to seventy eight degrees.
[0037] For mounting each blade 11 , to the rear hub 12 , the rear hub 12 includes spaced holes 12 a formed around the rear hub edge that are spaced equidistantly apart and are for alignment with the blade arc section 15 first and second connection holes 15 a and 15 b to receive fasteners fitted through the blade arc section 15 first and second connection 15 a and 15 b, respectively, that are turned into the rear hub 12 holes 12 a, as shown in FIG. 3 .
[0038] The configuration of the blades 11 provides, as shown in FIG. 5 , for receiving a wind flow A that has passed across a nose cone 35 that is secured to a forward end of the housing 27 , after that wind flow has travels across the forward hub 16 , it travels into and through the blades, converting wind energy into blade turning. Which blades 11 are, as set out above, connected to the rear hub 12 , cylinder 26 and forward hub 18 , and which hubs 12 and 18 are axially connected to a shaft, not shown, that is fitted to the hubs 12 and 18 , and passes through the center of the cylinder 26 and forward hub 18 and connects, to turn, a generator, not shown, that is contained in a housing 35 that is shown in FIGS. 1 , 4 , 5 and 8 , that show the forward hub 18 journaled or pivot connected to which housing rear end. Additionally, FIG. 5 shows a wind flow B that is shown as curving as it passes over the nose cone end 13 a and travels over the nose cone 13 , to travel along the housing 35 , and into the spaced blades 11 of the blade 11 curved portion, as shown in FIGS. 5 and 8 . Which wind flow B is thereby directed into the wind flow A that passes over the nose cone 13 and housing 35 , with the two wind flows then combining and passing into and through the blades 11 , as shown in FIGS. 5 and 8 , to turn the blades 11 . The combination of the blades 11 leading edge 19 that is curved by the blade 11 connection to the cylinder 25 , causes the combined wind flows A and B to travel outwardly from the blade greater to lesser thickness as that combined wind flow A and B travel around the blade arc of from seventy to seventy eight degrees, as shown in FIG. 4 , as non-turbulent flows with, the combined wind air flows then passing, turbulence free, off of the blade trailing edge 23 . Due to the shape of which blade 11 trailing edge 23 , the combined wind flows then travel off of the blade 11 trailing edge 23 as essentially turbulence free flows, as discussed below.
[0039] Shown in FIG. 6 , the nose cone 13 has a rounded dome shaped forward end 13 a and tapers outwardly to its end 13 b above a rear threaded section 19 . Which threaded section 19 is for turning in a threaded center portion the forward end 35 a of the housing, shown in FIG. 5 . Though, it should be understood, other coupling arrangements can be utilized for fitting the nose cone 13 onto the housing 35 forward end 35 a, within the scope of this disclosure. For example, FIG. 6A shows a side elevation section of forward end 35 a of the housing 35 as including a stepped section 35 b formed around its circumference, adjacent to the forward end 35 a, that the nose cone 13 is aligned to fit over. And the housing 35 stepped section 35 b is shown as including threaded spaced holes 35 c formed there around that align with spaced holes 13 c formed through the nose cone 13 , with the holes 35 c and 13 c each to receive a fastener, such as a bolt fitted thereto, for securing the nose cone 13 onto the housing 35 forward end 35 a.
[0040] In FIG. 6 the nose cone 13 is shown as tapering tapers outwardly from the junction of the dome to the nose cone side, shown as 13 b, to terminate in a nose cone end 13 c. Which taper is shown as angle C in FIG. 6 , and is an angle of approximately fifteen (15) to thirty (30) degrees. In practice, the radius of the dome from the dome center to side junction 13 b is approximately one half of the nose cone diameter, and which ratio can be from three eights to five eights within the scope of this disclosure. So arranged, a wind flow, arrow B, will travel smoothly over the nose cone dome end 13 a, along the side of the nose cone 13 , across the housing 35 surface, and into the blades 11 at each blade connection point 17 a to one of the spaced the tabs 27 that extend outwardly from the cylinder 26 surface, adjacent to the rear face of the forward hub 18 . Wind flows A and B, shown in FIGS. 5 and 8 , combine and flow into each blade 11 , across the blade leading edge 19 , and around the blade curve of from seventy to seventy eight degrees, without a creation of turbulence. In operation, the wind flow B combines and consolidates with the wind flow A and travels smoothly without turbulence over the blade surface, transferring the energy in the wind flows into blade turning, and then exhausts across the blade 11 trailing edge 23 . Which trailing edge 23 , as shown best in FIG. 2 , is curved at 24 , and that curve is reversed at 24 a, to a lesser essentially straight section 25 to the blade end 22 . Which curve 24 is extends from the blade rear edge to accommodate the consolidated wind flows A and B so as to discourage turbulence in that combined wind flow that then exhaust off of the blade trailing edge. Which exhaust wind flow continues to be a non turbulent flow as it separates off of the blade trailing edge 23 . Which combined non turbulent wind flow travel over the blades 11 and that turbulence is not created in the combined wind flow as it separates off of the blade tailing edge 23 produces a nearly one hundred percent efficiency in wind energy conversion into blade turning. So arranged, the combined wind flows A and B as have been exhausted off of the blade trailing edge 23 travel in a downward direction that is at an angle of approximately forty five degrees to the wind air flow direction into the wind sail receptor.
[0041] In practice, the arrangement of the wind sail receptor 10 blades 11 mounted around the rear hub 12 , where the blades 11 arc sections 15 are attached to the front face of the rear hub at equal intervals, provides for a secure and durable mounting to the blades 11 . So arranged, the combined wind flows A and B enter the blades 11 across the blade leading edge 19 accumulates at the blade trailing edge at curved section 24 to flow outwardly therefrom to where the curve is reversed at 24 a and then to the essentially straight section 25 , and off from the blade end 22 . Which curved section 24 has a greater length of edge to accommodate the combined wind flows A and B as have traveled across the blade 11 , and to smoothly exhaust the combined wind flows both across the blade at the curved section 24 , without a creating of turbulence and to guide the combined wind flows along the blade to exhaust off of the straight section 25 . Which combined wind flow passage off of the blade trailing edge 23 curved and straight sections 24 and 25 . In practice, the combination of which curved and straight sections 24 and 25 promotes a non-turbulent separation of the combined wind flow off of the blade trailing edge. Which wind air flow exhaust, because of the trailing edge 23 configuration, is smooth and does not create turbulence as it travels off of the blade trailing edge 23 , and this non turbulent wind air flow off the blade 11 at trailing edge separation promotes an efficient translation of the wind flow energy into blade turning with minimum wind energy losses.
[0042] Along with the shape of the blade 11 the trailing edge 23 , as discussed above, to maximize wind flow energy conversion into blade 11 turning, the bent blade 11 is curved in a uniform arc of from seventy to seventy eight degrees from its leading to trailing edges, 19 and 23 , respectively. This smooth curved surface maximizes wind energy conversion to blade turning and provides for a non turbulent wind air flow travel over the blade from leading to trailing edges. As set out above, this preferred uniform arc is formed in the bending of blade 11 from its mounting at blade arc section 15 end connection at holes 15 a across the cylinder 25 to the blade end 17 at connection point 17 a to the tab 27 that extends outwardly from the cylinder 25 , adjacent to the forward hub 18 . Which tab 27 , shown in FIGS. 1 , 3 and 4 , is formed to receive the blade end 17 engaging surface and to closely fit thereto. So arranged, the blade 11 curved surface 16 , shown in FIGS. 2 and 3 will fit tightly onto the cylinder 25 outer surface. So arranged, a secure coupling of the blade to the rear hub 12 and cylinder 26 is formed that will resist bending when wind energy is directed there against. And, of course, to further strengthen which blade to cylinder coupling, additional tabs 27 can to provided at spaced intervals along the cylinder 25 to align with spaced holes in the blade 17 that receive fasteners to further secure the blade end 17 to the cylinder 25 surface.
[0043] While the bend arc can be at an angle of from seventy to seventy eight degrees to produce the wind conversion efficiency, as set out above, for the four bladed six foot diameter wind sail receptor 10 the bent angle is preferably approximately fifteen (15) degrees. Additionally, as shown in FIG. 2 , where the curved section 24 of the blade 11 trailing edge 23 has an arc of approximately fifteen (15) degrees, this arc can be from ten (10) to twenty (20) degrees within the scope of this disclosure, and where the point along the arc is reversed, shown at 24 a, will be at a distance from the blade trailing edge end 22 that is approximately one fourth to one third of the distance from that blade 11 trailing edge end 22 . Also, to provide a close fit of the blade 11 to the cylinder 26 arc the blade curved section 16 to the blade end 17 , the curved section will have an arc from fifteen (15) to twenty five (25) degrees, and which arc can vary by plus or minus five (5) degrees, within the scope of this disclosure, depending upon the whether the wind sail receptor has three, four or five blades 11 , and the length of the blades 11 .
[0044] With the blades 11 bent to an arc of from seventy to seventy eight degrees, combined wind flows A and B will smoothly travel around the blade 11 arc and off of the blade trailing edge 23 at an angle of approximately forty five degrees to the direction of the wind flow entering the wind sail receptor 10 that travels over blade leading edge 19 , with little or no air flow traveling through the blades 11 . This wind flow re-direction provides a maximum utilization of the energy of the wind flow into wind sail receptor turning that closely approaches and one hundred per cent wind energy utilization to turn a generator to produce an electrical power output.
[0045] The wind sail receptor 10 is shown herein as having a six foot diameter the rear hub 12 , cylinder 26 and forward hub 18 that are approximately one foot in diameter. As set out above, however, the wind sail receptor 10 can be formed to have from three to five blades 11 but such configuration will require an alteration to the hub and cylinder diameter. For example, the hub and cylinder diameter for a five blade 11 wind sail receptor 10 with three foot blades will be approximately fifteen (15) inches, and the hub and cylinder diameter for a three bladed wind sail receptor 10 , where the blades are three feet in length will be approximately twelve (12) inches. Additionally, the wind sail receptor 10 can be upscaled with utilization of longer blades 11 and such will also require an alteration in the rear hub 12 , cylinder 26 and forward hub 18 diameter. For a wind sail receptor 10 that has twelve foot diameter across the blades ends, utilizing blades 11 that are approximately five feet in length, the hubs and cylinder 12 , 18 and 26 , respectively, should have approximately a one foot diameter, and, a wind sail receptor 10 with a diameter of twenty five feet across the blades ends, that will utilize blades 11 that are approximately ten feet in length, the hubs and cylinder, 12 , 18 and 26 , respectively will have a diameter of approximately five feet.
[0046] A preferred embodiment of the wind sail receptor of the invention has been shown and described above. It will, however, be apparent to one knowledgeable or skilled in the art that the above described embodiment may incorporate changes and modifications without departing from the general scope of this invention. Which invention is therefore intended to include all such modifications and alterations in so far as they come within the scope of the appended claims and/or a reasonable equivalence thereof.
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An improved wind sail receptor for turning in a wind flow to turn an axle that operates a generator to produce an electrical power output for performing work. With the improved wind sail receptor blade design and the inclusion of a unique shape of nose cone fitted over a forward end of a housing that the wind sail receptor is journaled to, the wind sail receptor provides for a nearly one hundred percent utilization of the entering wind flow energy to turn the wind sail receptor blades. This near perfect wind energy utilization is provided by the structure of the blades leading and trailing edges along with the blades uniform curvature between leading and trailing edges that is from seventy to seventy eight degrees of arc and the nose cone configuration, whereby a turbulence free wind flow passed off of the blades trailing edge is at a approximately a forty five degree angle to the entering wind flow.
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BACKGROUND OF THE INVENTION
The present invention relates generally to lighting which uses LEDs as light-generating elements.
SUMMARY OF THE INVENTION
In this case, the object of the present invention is to specify particularly advantageous configurations. An advantageous configuration is in this case firstly to be understood to mean that a large number of identical parts can also be used for LED emitters with different luminous efficacy (lumens) on the production side. Alternatively or in addition, an advantageous configuration can also be understood to mean that the luminous efficacy emitted by the LED emitter is conducted very efficiently from the emitter.
This object is achieved by the features of the independent claims. The dependent claims advantageously develop the central concept of the invention.
The invention provides a set of a plurality of LED emitters, wherein
the LED emitters in the set generate a different luminous efficacy, the LED emitters have a standard housing.
Each emitter can have an LED module with a plurality of LED chips, wherein the mid-distance between the LED chips of an LED module and also the mid-distance between LED chips of LED modules of different emitters is preferably constant. In this case, the mid-distance is the distance between the axes of symmetry of two mirror-symmetrical or rotationally symmetrical LED chips.
The mid-distance can be between 1.5 mm and 4 mm, preferably 2.5 to 4 mm.
The mid-distance between the LED chips which has been selected so as to be relatively small is used for improved luminous efficacy. By virtue of said small mid-distance between the LED chips on the LED module, homogenous white light is emitted by the LED modules or LED emitters, while the heat dissipation of the LED module remains optimized. The use of metal-core printed circuit boards as mounts for the LED module is in this case particularly advantageous.
The LED chips can be covered with a dispensed casting compound, such as a so-called dome-shaped globe top or another cover, for example, wherein the globe tops of adjacent LED chips preferably do not run with one another.
Globe tops which run with one another are also conceivable. In this exemplary embodiment, a plurality of LEDs are positioned beneath a common globe top.
Furthermore, the invention relates to an LED emitter, having:
a plurality of LED chips spaced uniformly apart from one another on a common mount, wherein the LED chips are covered by a casting compound, and the LED chips form a light field, a reflector, which is positioned directly on the mount, extends away from the mount and surrounds the light field narrowly on its side positioned on the mount
The light area can make up at least 30%, preferably at least 50%, even more preferably 55%, of the cross-sectional area of that side of the reflector which is positioned on the mount.
The lateral surface of the reflector can have a parabolic or a linear profile.
The surface of the reflector can be faceted and/or patterned.
The total area of the covered LED chips can make up at least 20%, preferably at least 25%, even more preferably at least 35%, of that side of the reflector which is positioned on the mount.
The LED emitter can be in the form of a so-called ceiling-mounted emitter for installation in suspended ceilings.
The LED emitter can have a housing with a light exit opening, which is covered by a diffuser (and/or phosphor disk) or is open.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages, features and properties of the invention will now be explained in more detail with reference to the description of an exemplary embodiment and the figures of the attached drawings.
FIGS. 1 , 2 and 3 show LED modules for LED emitters of different luminous efficacy, and
FIG. 4 shows an exploded view of an LED emitter with one of the LED modules shown in FIGS. 1 to 3 , and
FIG. 5 shows a facet reflector which can be used in the context of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates in particular to a group of identical LED emitters, wherein the group has LED emitters with different luminous efficacy (lumens). Emitters with at least two different luminous efficacies in this case have a different number of LED chips, but mounts (printed circuit boards) with identical dimensions, which ensures an increase in the number of identical parts even for LED emitters with different luminous efficacies.
In this case, FIG. 1 shows an LED module, i.e. a large number of LED chips 1 on a printed circuit board mount 2 . This LED module 3 in FIG. 1 can be provided for a luminous efficacy of 2000 lumens, for example.
FIG. 2 now shows a further LED module, which can be dimensioned, for example, for a luminous efficacy (when installed in an LED emitter) of 3000 lumens and correspondingly has more LED chips.
This LED module 4 has the same printed circuit board 5 as the LED module 6 illustrated in FIG. 3 for a luminous efficacy of 4000 lumens, for example, which LED module 6 therefore has an identical printed circuit board as regards dimensions and fitting holes 8 .
Further standardization can be provided in that the distance between the light spots, i.e. the mid-points of the LED chips 1 , is identical for all of the LED modules 3 , 5 , 6 in FIGS. 1 , 2 and 3 . The distance between the mid-points is in this case the distance between the axes of symmetry of two mirror-symmetrical or rotationally symmetrical LED chips.
The distance between the light spots (mid-point distance) can be, for example, between 2 and 4 mm, preferably between 3.2 and 3.8 mm. As has been mentioned, this distance between the light spots can be selected to be identical for the LED modules of different powers, which in turn can result in standardization possibilities (use of identical parts) as regards the downstream optics (reflector, diffuser, phosphor disk), which will be explained below with reference to FIG. 4 .
As can be seen from FIG. 4 , the LED module shown in FIGS. 1 , 2 and 3 , now denoted by the reference symbol 10 , is installed in an LED emitter, which can be used as a downlight or spotlight, for example. This emitter, denoted overall by 11 in FIG. 4 , has a bottom-side housing with a heat sink 32 , for example, on which the LED module 10 is fitted in thermal contact.
Preferably, at least essential parts of the bottom housing part 32 are manufactured from a material with high thermal conductivity, in particular from metal.
Preferably, a reflector 12 is positioned in direct contact on the printed circuit board of the LED module 10 , said reflector preferably being configured in such a way that that side 13 of the reflector which is open towards the LEDs has a smaller cross-sectional area than the exit side 14 of the reflector 12 which faces away from the LEDs. There is therefore a reflector which extends in the light emission direction.
The reflector is preferably rotationally symmetrical.
The contours (generatrices) of the reflector 12 can in this case be linear, with the result that a truncated cone shape is produced. Alternatively, however, other profiles are also conceivable, in particular bent profiles such as parabolic profiles, for example, for the contour of the lateral surface 15 of the reflector 12 .
Finally, an upper part 20 and a covering disk 21 with a central, preferably circular opening 22 is positioned on the bottom part 12 of the housing.
Optionally, a diffuser (not shown) can be inserted into the circular exit opening 22 , it being possible for said diffuser to optionally also perform further optical functions, in addition to the diffuser effect thereof. For example, a color conversion medium for changing the wavelength (for example in the form of a phosphor disk) can also be inserted into the diffuser, if used.
The phosphor disk can also be used without diffuse particles in the LED emitter. The use of phosphor disks and/or diffusers with patterned surfaces is also conceivable.
Overall, it is preferred, however, that a color conversion medium (for example inorganic or organic phosphors) 30 is applied in the form of a so-called globe top or in another way to the respective LED chip in direct contact therewith so as to generate white light.
As has been mentioned, the housing shown in FIG. 4 and the reflector are used in the form of identical parts for LED modules likewise with different dimensions and in any case different luminous efficacies (lumens).
The use of a phosphor disk in combination with a white reflector (which forms a highly reflective surface) is particularly preferred when the LED module 10 has LEDs of different spectrums, for example monochromatic LEDs, in particular red LEDs, in combination with a preferably phosphor-converted for example blue or UV LED (which emits white light, for example) or with a further monochromatic, for example blue or green LED. The phosphor-converted LEDs can emit green, white or red light, for example.
The reflector 12 having a highly reflective surface (for example white surface) ensures effective light mixing, with the result that the space delimited by the reflector 12 can also be referred to as a light mixing chamber within the LED emitter. Homogenous white light is generated from the monochromatic or from the monochromatic and phosphor-converted light-emitting diodes with the aid of the light mixing chamber.
An additional reflector (not shown), which can be positioned on the LED emitter 11 , is also conceivable. A multi-stage optics system with targeted light direction can be realized by means of this additional reflector.
The reflector 12 can be manufactured from a coated polymer, a metal such as aluminum etc.
The reflector consisting of metal in conjunction with a diffuser is preferred for the exemplary embodiments in which phosphor-converted LEDs are primarily used. By using a metal reflector, the light direction can be controlled as desired without the use of a multi-stage optics system.
Conventional metal reflectors can be incorporated in the LED emitters. They provide further standardization possibilities.
The reflector can be faceted, as is shown in the example in FIG. 5 .
The LED emitter 11 illustrated in FIG. 4 is used in particular as a replacement for existing emitters with conventional light-emitting means, which therefore use a halogen or xenon lamp as light-emitting means. This configuration is generally referred to as a “retrofit”.
In accordance with a further embodiment, the diameter of the reflector 12 is matched to the outer contour of the light field formed by the LEDs on the module 10 . In the case of a relatively small light field, such as in FIG. 1 , for example, therefore, a smaller reflector can be selected than in the case of a relatively large light field as illustrated in FIGS. 2 and 3 .
In this case, the invention is based on the principle that that opening side 13 of the reflector 12 which faces the LEDs surrounds the active light field (outer contour of the LEDs on the LED module 10 ) as narrowly as possible, which increases the efficiency (light output per electrical power, in watts) of the depicted LED emitter 11 . Since the distance between the light spots is selected to be as small as possible, as mentioned already at the outset, the area of the entry side 13 of the extending reflector 12 can therefore also be kept as small as possible.
As can already be seen schematically in FIG. 4 , the extending reflector 12 according to the invention is positioned directly on the printed circuit board of the LED module 10 and is not spaced apart therefrom, which further increases the luminous efficacy.
A further concept of the present invention consists in that the active light field is formed by discrete light spots (LED chips spaced apart from one another with separate coating in the form of globe tops), but the “fill level” of the light field, i.e. the total area of the globe tops in comparison to the area formed by the outer contour of the light field, is as high as possible.
Preferably, the fill level of the light field, i.e. the proportion of the area of the outer contour of the light field made up by the globe top area, is at least 15%, preferably 20%, even more preferably 35%.
A further important parameter according to the invention is the ratio of the area of the outer contour of the light field to the area of the entry side 13 of the reflector 12 . According to the invention, the area of the outer contour of the light field is at least 30%, preferably 50%, even more preferably 55%, of the area of the entry side 13 of the extending reflector 12 .
As can be seen schematically in FIG. 4 , the outer side of the upper part 20 of the housing of the LED emitter 11 , said upper part being manufactured from polymer (with a high thermal conductivity), for example, can be profiled so as to form cooling ribs 25 .
These cooling ribs can extend beyond the cover part 21 as well (see reference symbol 26 ).
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Set of a plurality of LED emitters, wherein the LED emitters in the set generate a different luminous efficacy, and have a standard housing.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a wound dressing, and more particularly to a bandage. 2. Description of the Prior Arts
[0003] The conventional method for fabricating a bandage containing chitosan is coating a solution or powder of chitosan to a non-woven fabric made from cotton fibers or synthetic fibers. The fabricating method is easy and simple, but the chitosan would easily remain on a surface of the non-woven fabric. If chitosan particles enter the blood vessel through the wound, vessel occlusion, even a stroke will occur. The fabricating method can make chitosan fibers directly into a non-woven fabric, but the mechanical strength of the chitosan fabric would be weakened after the chitosan fiber absorbs blood or body fluid to swell and even dissolve. Consequently, the conventional bandage sticks to wounds easily, such that replacement with new dressings is difficult and even results in secondary injury. Furthermore, as the mechanical strength of conventional chitosan fiber is weak, weaving chitosan fibers into a bandage is also difficult.
SUMMARY OF THE INVENTION
[0004] To overcome the shortcoming of chitosan fibers' lack of strength, the objective of the present invention is to provide a method for fabricating a bandage having chitosan yarn with sufficient strength.
[0005] To achieve the above objective, the method in accordance with the present invention comprises the following steps:
[0006] (a) preparing multiple complex yarns each including chitosan fibers and rayon fibers;
[0007] (b) weaving solely the multiple complex yarns to form a preformed bandage;
[0008] (c) immersing the preformed bandage in an acid alcohol, and then washing the preformed bandage by alcohol to obtain an alcohol-washed bandage; and,
[0009] (d) heating the alcohol-washed bandage to obtain the bandage.
[0010] According to the present invention, the term “solely”, as used herein, refers to that the preformed bandage is consisted of said multiple complex yarns and without any other yarns that include any fiber other than chitosan fiber and rayon fiber.
[0011] Preferably, the chitosan fibers and rayon fibers are prepared separately by cotton carding, doubling, and twisting in regular turn.
[0012] Preferably, a concentration of the chitosan fibers in the complex yarns is between 10 wt % and 50 wt % of a total weight of the complex yarns.
[0013] Preferably, a concentration of the chitosan fibers in the complex yarns is between 20 wt % and 45 wt % of a total weight of the complex yarns.
[0014] Preferably, the acid alcohol comprises a weak acid, wherein the weak acid includes, but is not limited to, acetic acid, lactic acid, citric acid, succinic acid and glycolic acid.
[0015] Preferably, a concentration of the weak acid is between 3 wt % and 5 wt % of a total weight of the acid alcohol.
[0016] In a second aspect, the present invention provides a bandage prepared from the above-mentioned method, wherein the bandage is comprised of the complex yarns, wherein the complex yarns are each consisted of the chitosan fibers and the rayon fibers.
[0017] The bandage in accordance with the present invention is comprised of the complex yarns, wherein the complex yarns are each composed of chitosan fibers and rayon fibers. The bandage not only has increased tensile strength and promotes coagulation, but also decreases dissolution rate for medical dressings. The advantage of the bandage with the chitosan fibers in accordance with the present invention is that such bandage could be removed easily from a wound without leaving residue in the wound.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a flow chart of the method for producing a bandage in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
[0020] As shown in FIG. 1 , the present invention provides a method for fabricating a bandage having multiple chitosan yarns. At first, complex yarns each including chitosan yarns and rayon yarns are prepared. Preferably, in one embodiment, the concentration of the chitosan yarns is between 10 wt % and 50 wt % of the total weight of the complex yarns. More preferably, the concentration of the chitosan yarns is between 20 wt % and 45 wt % of the total weight of the complex yarns. Most preferably, the concentration of the chitosan yarns is between 30 wt % and 40 wt % of the total weight of the complex yarns.
[0021] The complex yarns in accordance with the present invention could be prepared by the following method. For example, the complex yarns each include chitosan fibers and rayon fibers, wherein the chitosan fibers are prepared by wet spinning, and the rayon fibers are prepared by cotton carding. Then the complex yarns are formed by doubling and twisting the chitosan fibers and rayon fibers.
[0022] Second, the multiple complex yarns are woven excluding other yarns to form a preformed bandage.
[0023] Third, the preformed bandage is immersed in an acid alcohol, and then the amino group of the preformed bandage is changed to ammonium group, such that the ammonium group can coagulate red blood cell and blood platelets on a surface of the wound. Preferably, the acid alcohol comprises a weak acid, and a concentration of the weak acid is between 3 wt % and 5 wt % of the total weight of the complex yarns. Preferably, the weak acid is acetic acid, lactic acid, citric acid, succinic acid or glycolic acid. Preferably, the incubation time of the preformed bandage immersed into the acid alcohol is about 30 minutes. After immersing, the bandage is washed by alcohol to remove the weak acid and to obtain an alcohol-washed bandage.
[0024] Finally, the alcohol-washed bandage is heated to obtain the bandage.
[0025] The yarns of the bandage obtained from the above method comprise complex yarns, wherein the complex yarns are each composed of chitosan fibers and rayon fibers. Moreover, after the preformed bandage is immersed in the acid alcohol, the chitosan fiber of the bandage can promote coagulation.
[0026] There are some tests as described below utilizing various chitosan contents of the complex yarns to prepare bandages by the above-mentioned method.
EXAMPLE 1
The Coagulation Test
[0027] 100 μl blood was separately dropped on bandage samples of the present invention having various chitosan contents, samples of commercially available products having functions of promoting coagulation, control sample of non-woven fabrics having chitosan fibers or rayon fibers. Waiting for about 30 seconds to 240 seconds, the above-mentioned samples were each put into 10 ml physiologic saline to stir for 120 seconds to lyse the blood from the samples, and the absorbance of the samples were measured at 540 nm. 100 μl blood and 10 ml physiologic saline was defined as a standard sample and the absorbance at 540 nm was defined as 1. Then, the absorbances of the samples were compared to obtain a relative absorbance to quantify the hemolytic dose of each sample. A higher relative absorbance means a higher hemolytic dose and thus decreased activity of coagulation.
[0000]
TABLE 1
The hemolytic doses of the bandages samples woven of
complex yarns, commercially available products, and
control sample
amount of
chitosan
incubation time (seconds)
sample
(wt %)
30
60
120
240
the bandage
1
10
0.17
0.12
0.01
0.08
comprised of
2
20
0.14
0.11
0.08
0.05
complex yarns
3
30
0.11
0.07
0.06
0.03
4
40
0.09
0.06
0.06
0.03
5
45
0.13
0.09
0.09
0.07
6
50
0.17
0.11
0.13
0.09
7 1
100
0.65
0.45
0.21
0.27
HemCon ® bandage 2
14
0.24
0.22
0.17
0.16
Celox ® bandage 3
22
0.31
0.21
0.15
0.17
Celox ® styptic
>95
0.44
0.34
0.17
0.17
powder 4
Conventional
100
0.16
0.10
0.08
0.08
non-woven fabric
having chitosan fibers
rayon fiber only 5
0
0.69
0.70
0.64
0.70
1 the bandage was comprised of 100 wt % chitosan long fibers
2 the bandage was prepared by blending PET fibers and rayon fibers, coating the chitosan solution, and heating in regular turn.
3 the bandage was prepared by coating chitosan powder onto non-woven cotton fabrics.
4 the styptic powder was composed of chitosan powder.
5 the bandage was consisted of rayon fibers.
[0028] The results of the hemolytic dose test were presented in Table 1. The results of the samples 1 to 7 demonstrated that while the contents of chitosan were between 10 wt % and 100 wt %, the hemolytic dose reached the minimum when the chitosan amount ranged from about 30 wt % to 40 wt %, and the variation tendency of the hemolytic dose was decreasing first and then increasing. Further, the blood coagulation by the complex yarns having the chitosan content ranging from 30 wt % to 40 wt % was the best of all. Besides, comparing the hemolytic doses of the bandages having chitosan fiber and of the commercially available products, the coagulation by sample 1 having 10 wt % chitosan fiber was better than the commercially available HemCon® bandage having 14 wt % chitosan; the coagulation by sample 2 having 20 wt % chitosan fiber was twice the commercially available Celox® bandage having 22 wt % chitosan and close to the conventional non-woven fabric having chitosan fibers , not to mention the commercially available Celox® styptic powder that has more than 95 wt % chitosan. Particularly, due to lower efficiency of solution absorbance, the sample 7 comprised of all chitosan long fibers had decreasing coagulation. Thus, the coagulation efficiency of the bandage composed of complex yarns having chitosan fibers and rayon fibers was superior beyond expectation.
EXAMPLE 2
The Lytic Test
[0029] 0.5 g of the bandage samples, of the samples of commercially available products, and of the control sample each containing a different amount of chitosan were separately placed into sample bottles. 20 ml physiologic saline was added into each sample bottle. Each sample bottle was stirred for 10 minutes to 60 minutes. Then, the solutions from each sample bottle were filtered, heated, and weighed to calculate the dissolution rates of the above-mentioned samples.
[0000]
TABLE 2
The dissolution rate of the bandage woven of complex yarns,
the commercially available products and control sample
amount of
chitosan
stirring time (minutes)
sample
(wt %)
10
20
30
60
the bandage
1
10
2
4
4
4
comprised of
2
20
2
5
5
6
complex yarns
3
30
4
6
6
7
4
40
6
7
9
10
5
45
6
9
9
11
6
50
8
10
12
14
7 1
100
10
15
21
29
commercially
14
9
10
10
10
available HemCon ®
bandage 2
commercially
22
9
10
10
12
available Celox ®
bandage 3
commercially
>95
100
100
100
100
available Celox ®
styptic powder 4
conventional
100
46
58
66
78
non-woven fabrics
having chitosan fibers
1 the bandage was comprised of 100 wt % chitosan long fibers
2 the bandage was prepared by blending PET fibers and rayon fibers, coating the chitosan solution, and heating in regular turn.
3 the bandage was prepared by coating chitosan powder onto cotton non-woven fabrics.
4 the styptic powder was composed of chitosan powder.
[0030] The results of dissolution rate were presented in Table 2. The results of the samples 1 to 7 demonstrated that while the contents of chitosan were between 10 wt % and 100 wt %, the dissolution rates were increasing in compliance with the increasing chitosan. While the contents of chitosan in the bandage and in the commercially available products were equal, dissolution rates were increasing in accordance with the stirring time. When the contents of chitosan ranged from 10 wt % to 40 wt %, the dissolution rate was within 10 wt %. Comparing the sample 7, commercially available Celox® styptic powder, and the conventional non-woven fabric having chitosan fibers, though the contents of chitosan were more than 95 wt % or 100wt %, the dissolution rates of each of them were different. Wherein the commercially available Celox® styptic powder had the highest dissolution rate, followed by the conventional non-woven fabric having chitosan fibers, and the sample 7 had the lowest dissolution rate. Thus, dissolution rate would be affected by the shape of chitosan, and dissolution rate was decreasing in coordination with increasing length of chitosan.
EXAMPLE 3
The Tensile Strength Test
[0031] Bandages made of complex yarns having various chitosan contents, samples of commercially available products, and control sample of non-woven fabrics having chitosan fibers or only rayon fibers were separately cut into 7 cm×2 cm. Each sample was clamped by 2 cm at both ends with 3cm unclamped between the clamped ends , stretched by 60 mm/min constant speed until breaking to measure tensile strength of the above-mentioned samples.
[0000]
TABLE 3
The tensile strength of the bandage woven of complex yarns,
the commercially available products and the control sample
amount of
Tensile
chitosan
strength
Sample
(wt %)
(kgf/cm 2 )
the bandage
1
10
30.6
comprised of
2
20
28.2
complex yarns
3
30
26.8
6
50
18.4
Celox ® bandage*
22
18.1
non-woven fabric
100
14.6
having chitosan fibers
rayon fiber only
0
31.3
*prepared by coating chitosan powder onto cotton non-woven fabrics.
[0032] The results of the samples 1 to 3 and 6 were demonstrated in Table 3. The tensile strength was decreasing in accordance with the increasing chitosan. The tendency also could be demonstrated by that the non-woven fabric having chitosan fibers had the minimum tensile strength and the rayon fibers had the maximum tensile strength. Particularly, the tensile strength of sample 6 having 50 wt % chitosan is superior to the tensile strength of the commercially available Celox® bandage. Thus, the tensile strength of the bandage prepared by the above-mentioned method is fairly good.
EXAMPLE 4
The Cytotoxic Test
[0033] ISO 10993-5 test for in vitro cytotoxicity was used to test biocompability of the medical material by cell culture. The ISO 10993-5 test comprised direct contact method, agar diffusion method, and MEM elution, and herein the method adopted was the direct contact method. Only the cells located under the above-mentioned samples were injured. Thus, the above-mentioned samples were slightly cytotoxic within a bearable range for adoption on humans.
[0034] Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
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A method for fabricating a bandage comprises the following steps: preparing multiple complex yarns each comprising chitosan fibers and rayon fibers; (b) weaving solely the multiple complex yarns to form a preformed bandage; (c) immersing the preformed bandage in an acid alcohol, and then washing the preformed bandage by alcohol to obtain an alcohol-washed bandage; and, (d) heating the alcohol-washed bandage to obtain the bandage. The bandage related to the method is comprised of complex yarns, wherein each of the complex yarns is composed of chitosan fibers and rayon fibers. By means of immersing the preformed bandage into an acid alcohol, the bandage thus obtained has enhanced tensile strength, decreased dissolution rate and reduced hemolytic dose.
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FIELD OF THE INVENTION
The present invention relates generally to hinge and more specifically to a door hinge with a motion closure system for soft closure of the door.
BACKGROUND OF THE INVENTION
The conventional door hinge or butt-hinge is composed of two leaves each engages with the other by means of a pivot pin and interlocking sleeve, knuckle or pintle. One leaf is fixed on the door edge and the other is fixed on the door frame. One or more hinges are used to pivot the door when opening or closing the door. For automatically closure of the door with a conventional hinge, a hydraulic system, spring system or a combination system is typically affixed to the upper portion of door and to the horizontal beam of the upper door frame, thereby adding an industrial appearance to the door assembly. In addition, such door closing systems generally exerts a continuous resisting force requiring a big force to be applied to push the door open or hold the door in an open position, preventing the door from free swinging.
Moreover, such door closing systems apply a non-uniform force to the upper portion of the door disadvantageously resulting in a force offset from the rotational axis of the hinge assembly, thus deforming the door, hinge, latch/lock and frame over time. Furthermore, these door closing systems frequently utilize a separate mechanical mechanism to lock the door in a full open position such as a door stop or a mechanical elbow linkage requiring a separate installation. When a door is closed with the assistance of such door closing systems, it is typically forced to move in its closing direction rapidly, causing a noise to the ear and forceful impact, wherein the main elements the hinge, lock and door elements are impaired over time due to such force.
Therefore, it is readily apparent that there is a recognizable unmet need for control motion hinge for soft and quiet closure of a door during final approach, wherein such control motion hinge is integrated into the hinge or hidden within the door jam, frame or door, and wherein such control motion hinge is non-continuous, thereby allowing the door to swing freely through the door hinges full range of motion to an automatic full open hold position, and reduce the stress on the door, hinge, latch/lock and frame.
BRIEF SUMMARY OF THE INVENTION
Briefly described, in a preferred embodiment, the present apparatus overcomes the above-mentioned disadvantage, and meets the recognized need for such an apparatus by providing a control motion hinge comprising, in general, a first leaf hinge to secure a first pin, a second hinge to secure a first pin, a link positioned between the first and second leaf hinge, a flat spring wrapped around the knuckle of the first and second leaf hinge, activates a closure cycle of the control motion hinge pulling the door closed.
According to its major aspects and broadly stated, the present apparatus in its preferred form is a control motion hinge, comprising a first leaf hinge with three knuckles to secure a first pin, wherein the two outer knuckles have roller knuckles, a link having a two knuckles on a first end to interlock with the first leaf hinge and a single knuckle on a second end, a second leaf hinge with two knuckles to secure a second pin when interlocked with the second end of the link, wherein the two knuckles of the second leaf hinge have a roller path for engaging the roller of the first leaf hinge, wherein such rollers traverse the roller path, and thus softly closing the door reducing the sound of closure during the final approach of the door.
More specifically, the preferred embodiment of the present apparatus further comprising a roller path having a roller stop at a first end of the roller path and a roller ramp or plateau at a second end of the roller path for holding the closing system in an open door position, wherein release thereof activates a seamless closure cycle of the control motion hinge pulling the door closed.
In a further preferred embodiment of the control motion hinge, including a first hinge pin, a first leaf hinge having two or more knuckles to removably secure the first hinge pin and adapted to be fixed to the jam, a second hinge pin, a second leaf hinge having two or more knuckles to removably secure the second hinge pin and adapted to be fixed to the door, and a link having one or more knuckles on a first end to interlock with the two or more knuckles of the first leaf hinge and one or more knuckles on a second end to interlock with the two or more knuckles of the second leaf hinge.
In a further exemplary embodiment a method for an automatic closing hinge, including the steps of: providing a first hinge pin, a first leaf hinge having two or more knuckles to removably secure the first hinge pin and adapted to be fixed to the jam, wherein at least one of the two or more knuckles of the first leaf hinge further comprises a pair of roller sleeves, a roller pin and a roller, a second hinge pin, a second leaf hinge having two or more knuckles to removably secure the second hinge pin and adapted to be fixed to the door, wherein at least one of the two or more knuckles of the second leaf hinge further comprises a roller path for engaging the roller of the first leaf hinge, a link having one or more knuckles on a first end to interlock with the two or more knuckles of the first leaf hinge and one or more knuckles on a second end to interlock with the two or more knuckles of the second leaf hinge, and a spring in contact with an upper surface of the link and an outer surface of the two or more knuckles of the second leaf hinge, rotating the first leaf hinge apart from the second leaf hinge, traversing the roller along the roller path, expanding the spring while the first leaf hinge rotates apart from the second leaf hinge, and contracting the spring returns the first leaf hinge toward the second leaf hinge and the roller returns along the roller path.
Accordingly, a feature of the present control motion hinge is its ability to provide a hinge with a continuous closure force, thus allowing the door to close at a controlled rate of speed when the hinge is released.
Another feature of the present control motion hinge is its ability to provide a hinge wherein the closure system integrated as part of the hinge or knuckle, or hidden within the door jam, door frame or within the door, rendering an enhanced aesthetic appearance.
Still another feature of the present control motion hinge is its ability to provide a dampening closure cylinder utilizing hydraulic oil, nitric oxide, air or other compressible material.
Yet another feature of the present control motion hinge is its ability to provide a hinge that softly closes the door reducing the sound of closure during the final approach of the door.
Yet another feature of the present control motion hinge is its ability to provide a door hinge with a soft closure system that prevents a door from rapid closing so as to protect the door, jam, doorframe, or surroundings from being damaged.
Yet another feature of the present control motion hinge is its ability to provide a hinge with a soft closure system that cushions door closure, thereby reducing the stress on the door, hinge, latch/lock, jam, and frame.
Yet another feature of the present control motion hinge is its ability to provide a hinge with seamless motion throughout the hinges full range of motion.
Yet another feature of the present control motion hinge is its ability to provide a simple, compact, and inexpensive hinge with a seamless lock open and release mechanism and a closure system.
Yet another feature of the present control motion hinge is its ability to provide a door closer, which can smoothly and effectively close the door after opening and releasing.
Yet another feature of the present control motion hinge is its ability to hold the door in a full open position, release the door there from, and maintain a controlled closure motion through the door's final approach.
Yet another feature of the present control motion hinge is its ability to reduce the opening force required to open the door facilitating accessibility for small children, elderly, handicapped and those with disabilities.
Yet another feature of the present control motion hinge is its ability to provide a door hinge that can motion the door to a closed position in a smooth and slow manner during final approach.
Yet another feature of the present control motion hinge is its ability to provide a hinge assembly that can be sold as a replacement hinge assembly for retrofitting and improving existing hinges.
These and other features of the control motion hinge will become more apparent to one skilled in the art from the following Detailed Description of the Preferred and Selected Alternate Embodiments and Claims when read in light of the accompanying drawing Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The present control motion hinge will be better understood by reading the Detailed Description of the Preferred and Selected Alternate Embodiments with reference to the accompanying drawing figures, in which like reference numerals denote similar structure and refer to like elements throughout, and in which:
FIG. 1 is a front view of a prior art door assembly showing three hinges spaced vertically between a door frame and a swinging door, showing the hinges in a closed state;
FIG. 1.1 is an enlarged perspective view showing a prior art door hinge shown in FIG. 1 in the open state;
FIG. 2 is a perspective view of a control motion hinge according to a preferred embodiment;
FIG. 3 is an enlarged perspective view of the control motion hinge of FIG. 2 , shown in the open state;
FIGS. 4 , 4 . 1 , 4 . 2 , 4 . 3 , and 4 . 4 are exploded perspective views of the two leaf hinges, link and flat spring assembly according to a preferred embodiment;
FIGS. 5 , 5 . 1 , 5 . 2 , 5 . 3 , 5 . 4 and 5 . 5 are expanded partial cross-sectional side views of the control motion hinge of FIG. 2 , shown in the closed, partially open, and open states; and
FIGS. 6 , 6 . 1 and 6 . 2 are expanded partial cross-sectional side views of the control motion hinge with integrated dampener of FIG. 2 , shown in the closed and open states.
DETAILED DESCRIPTION OF THE INVENTION
In describing the preferred and alternate embodiments of the present invention, as illustrated in FIGS. 1-6 specific terminology is employed for the sake of clarity. The present invention, however, is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish similar functions.
Referring now to FIGS. 1 and 1 . 1 , there is depicted a prior art door D, door jam J, door header I and three hinge assembly H 1 , H 2 , and H 3 . The door D, which swings inward, toward the viewer as depicted in FIG. 1 , fits closely to jam J at both its hinge edge A 1 and its opposite or latch edge A 2 . Door A may be configured to swing inward or outward by switching the configuration of hinge assembly H 1 , H 2 , and H 3 . It should be noted, also, that no hinge is exposed to view along the hinge edge A 1 when the door is closed as viewed from the other side of door D.
Referring now to FIG. 1.1 , a perspective view of a typical prior art hinge assembly H having two hinge leaves formed as a pair, stationary hinge leaf L 1 and rotatable hinge leaf L 2 , and connected therebetween by hinge pin P. The hinge leaves (L 1 , L 2 ) have offset knuckles K which when interlinked are preferably joined together by the hinge pin P. Each hinge leaf is shown with three mount holes M 1 , M 2 , and M 3 formed in the hinge leaves. The stationary hinge leaf L 1 is secured to door jam J utilizes a flathead screw, nail or the like driven through mount holes M of such stationary hinge leaf L 1 , while the rotatable hinge leaf L 2 is secured to opening-and-closing door D, or the like, also utilizes a flat screw, nail or the like driven through mount holes M of such rotatable hinge leaf L 2 . To hang door D to door jam J, door D is positioned near door jam J so that knuckles K of stationary hinge leaf L 1 are interlinked with knuckles K of rotatable hinge leaf L 2 and pin P is inserted into such interlinked knuckles of stationary hinge leaf L 1 and rotatable hinge leaf L 2 , thereby enables door A to freely rotationally swing about pin P with stationary hinge leaf L 1 affixed to door jam J.
Referring now to FIGS. 2 and 3 , by way of example, and not limitation, there is illustrated a perspective view of control motion hinge 10 in accordance with a preferred embodiment of the present invention. Preferably, control motion hinge 10 , having stationary hinge leaf 12 , rotatable hinge leaf 14 , knuckles 18 , 19 , link 21 , and stationary hinge pin 16 and rotatable hinge pin 17 are preferably formed of a suitable material, such as aluminum, brass, iron, steel, or other metals, plastic, including various finishes from chrome, antiqued copper, black, and brass (either plated or pure brass) or the like, capable of providing structure and strength to hinge assembly H. Preferably, the material includes other suitable characteristics, such as durability, water-resistance, light weight, malleable, oxidation resistance, ease of workability, or other beneficial characteristic understood by one skilled in the art. Moreover, hinge 10 may come in an endless variety of types, shapes, sizes and purposes, including but not limited to butt hinges, strap hinge, spring hinge, wide throw hinge, left hand, right hand hinge and the like.
Referring now to FIGS. 2 and 3 , the present invention in its preferred embodiment is a control motion hinge 10 . Preferably, control motion hinge 10 comprises two hinge leaves formed as a pair, stationary hinge leaf 12 , and rotatable hinge leaf 14 , and connected therebetween by a link 21 . The hinge leaves ( 12 , 14 ) preferably have offset knuckles 18 , which interlocked with offset knuckles 19 of link 21 and thereby joined together as a combination linkage by stationary hinge pin 16 and rotatable hinge pin 17 .
Referring now to FIGS. 2 and 3 , control motion hinge 10 is preferably shown in a partial open position and shown having flat spring 22 coupled around offset knuckles 18 of stationary hinge leaf 12 and offset knuckles 19 of link 21 .
Referring now to FIG. 3 , control motion hinge 10 is preferably shown in an approximately full open position and shown having roller 32 positioned between roller sleeve 33 and roller sleeve 35 , which preferably are positioned on the underside surface of one or more offset knuckles 18 of rotatable hinge leaf 14 and held rotationally in position by roller pin 36 . In operation, roller 32 traverses roller path 34 of offset knuckles 18 of stationary hinge leaf 12 between roller stop 38 and roller closing ramp 31 . Moreover, one or more mount holes 37 (four shown) are positioned in stationary hinge leaf 12 and rotatable hinge leaf 14 .
Referring now to FIGS. 4 , 4 . 1 , 4 . 2 , 4 . 3 , 4 . 4 , by way of example, and not limitation, there is illustrated an exploded perspective view of control motion hinge 10 in accordance with a preferred embodiment of the present invention. Referring again to FIG. 4.1 , there is illustrated an exploded perspective view of rotatable hinge leaf 14 of control motion hinge 10 . Preferably, rotatable hinge leaf 14 includes flat single geometric plane 41 arranged as rectangle or other geometric shape and further preferably having one or more mount holes 37 (four shown) positioned in rotatable hinge leaf 14 for removably attach rotatable hinge leaf 14 to door D (as shown in FIGS. 2 and 3 ) utilizes a flathead screw, nail or the like driven through mount holes 37 of such rotatable hinge leaf 14 . Edge 43 preferably runs the perimeter of plane 41 . On one segment of edge 43 of rotatable hinge leaf 14 preferably includes one or more offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 having pin hole 45 . 1 operative to run linearly there through each offset knuckle 18 . 1 , 18 . 2 , and 18 . 3 . Referring again to FIG. 4.2 , there is illustrated an exploded perspective view of link 21 of control motion hinge 10 . Preferably, link 21 includes on one end of link one or more offset knuckles 19 . 1 and 19 . 2 having pin hole 45 . 2 operative to run linearly there through each offset knuckle 19 . 1 and 19 . 2 .
In use, offset knuckles 19 . 1 and 19 . 2 of link 21 are preferably interlock or fit together closely with offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 of rotatable hinge leaf 14 , whereby rotatable hinge pin 17 is positioned within pin holes 45 . 1 of offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 and pin holes 45 . 2 of offset knuckles 19 . 1 and 19 . 2 to rotationally connect link 21 and rotatable hinge leaf 14 .
Referring again to FIG. 4.1 , there is illustrated an exploded perspective view of rotatable hinge leaf 14 of control motion hinge 10 . Preferably, roller sleeve 33 and roller sleeve 35 are affixed to the adjacent or situated near or close or touching exterior surface of both knuckles 18 . 1 and 18 . 3 and roller 32 is positioned there between roller sleeve 33 and roller sleeve 35 and held in position when roller pin 36 is positioned within pin holes 45 . 3 of roller sleeve 33 and roller sleeve 35 .
Referring again to FIG. 4.3 , there is illustrated an exploded perspective view of stationary hinge leaf 12 of control motion hinge 10 . Preferably, stationary hinge leaf includes flat single geometric plane 41 arranged as rectangle or other geometric shape and further preferably having one or more mount holes 37 (four shown) positioned in stationary hinge leaf 12 for removably attach stationary hinge leaf 12 to jam J (as shown in FIGS. 2 and 3 ) utilizes a flathead screw, nail or the like driven through mount holes 37 of such stationary hinge leaf 12 . Edge 43 preferably runs the perimeter of plane 41 . On one segment of edge 43 preferably includes one or more offset knuckles 18 . 4 and 18 . 5 having pin hole 45 . 4 operative to run linearly there through each offset knuckle 18 . 4 and 18 . 5 . Referring again to FIG. 4.2 , there is illustrated an exploded perspective view of link 21 of control motion hinge 10 . Preferably, link 21 preferably includes on the other end at least one offset knuckle 19 . 3 having pin hole 45 . 5 operative to run linearly there through knuckle 19 . 3 .
In use, offset knuckle 19 . 3 of link 21 is preferably interlocked with offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 , whereby stationary hinge pin 16 is positioned within pin hole 45 . 5 of offset knuckle 19 . 3 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 to rotationally connect link 21 and stationary hinge leaf 12 .
Furthermore, when in combination use, stationary hinge pin 16 is positioned within pin hole 45 . 5 of offset knuckle 19 . 3 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 to rotationally connect link 21 and stationary hinge leaf 12 , and rotatable hinge pin 17 is positioned within pin holes 45 . 1 of offset knuckles 18 . 1 , 18 . 2 , and 18 . 3 and pin holes 45 . 2 of offset knuckles 19 . 1 and 19 . 2 to rotationally connect link 21 and rotatable hinge leaf 14 , control motion hinge 10 preferably is a three member linkage hinge constructed of stationary hinge leaf 12 , link 21 , and rotatable hinge leaf 14 .
It is recognized that plane 41 of rotatable hinge leaf 14 and stationary hinge leaf 12 is preferably configured as a four (4) inch pattern rated for approximately 75 pounds or a four and a half (4.5) inch pattern rated for approximately 75-115 pounds; however, different sizes and/or configurations are contemplated herein.
Referring again to FIG. 4.4 , there is illustrated an exploded perspective view of flat spring 22 of control motion hinge 10 . Preferably, flat spring 22 is formed to match the exterior surface and contours of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 and is generally ‘C’ shaped. Moreover, flat spring 22 is preferably formed of a suitable material, such as metal, steel, stainless steel or the like, capable of providing suitable characteristics, such as shape memory, magnetism, durability, water-resistance, light weight, heat-resistance, chemical inertness, oxidation resistance, ease of workability, or other beneficial characteristic understood by one skilled in the art. Preferably, flat spring 22 includes inner-upper surface 49 and inner-lower surface 51 and when in use both surfaces are in contact with the outer surface of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 . Moreover, inner-upper surface 49 of flat spring 22 is preferably arranged to rest on upper surface 44 of link 21 and attached thereto by spring screws or the like inserted in screw holes 53 formed in flat spring 22 and screw holes 42 formed in upper surface 44 of link 21 . In use, flat spring 22 is preferably positioned on the outer surface of offset knuckles 18 . 4 and 18 . 5 of stationary hinge leaf 12 and on upper surface 44 of link 21 , in order to function as a spring when link 21 rotates about stationary hinge pin 16 positioned within pin hole 45 . 5 of offset knuckle 19 . 3 of link 21 and pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 . In general flat spring 22 operates, preferably when an arc rotation (kinetic) of link about stationary hinge pin 16 positioned within pin holes 45 . 4 of offset knuckles 18 . 4 and 18 . 5 separates inner-upper surface 49 of flat spring 22 from inner-lower surface 51 of flat spring 22 , which further results in an opposite force (potential) of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions.
It is contemplated that roller pin 36 , rotatable hinge pin 17 , stationary hinge pin 16 , and screws 47 could be interchangeably replaced with pins, screws bolts, pins and cotter keys, rivets or other like attachment devices.
Hinge Open Cycle
Referring now to FIGS. 5 , 5 . 1 , 5 . 2 , 5 . 3 , 5 . 4 , 5 . 5 by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in motion, in accordance with a preferred embodiment of the present invention. Referring again to FIG. 5.1 , there is illustrated a side view of control motion hinge 10 shown in a hinge-closed position with door D closed against jam J. Preferably, roller 32 and roller sleeve 35 of rotatable hinge leaf 14 are positioned against roller stop 38 of roller path 34 of offset knuckles 18 . 5 of stationary hinge leaf 12 . Preferably, arch a in FIG. 5.1 is the angle between plane 41 of stationary hinge leaf 12 and upper surface 44 of link 21 . Preferably, arc a in FIG. 5.1 comprise equivalent arc angle of −5 degrees; however, arc a may be between approximately 0 degrees and −10 degrees. Preferably, arc a 1 in FIG. 5.1 is the angle between plane 41 of stationary hinge leaf 12 and rotatable hinge leaf 14 . Preferably, arc a 1 in FIG. 5.1 comprise equivalent arc angle of 0 degrees; however, arc a 1 may be between approximately 2 degrees and −2 degrees.
Referring again to FIG. 5.2 , there is illustrated a side view of control motion hinge 10 shown in a hinge-beginning-to-open position. Preferably, as door D is pushed open expands arc a 1 , rotatable hinge leaf 14 rotates about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 , which further rotates link 21 about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 . Rotatable hinge leaf 14 is preferably configured having the center-point of rotatable hinge pin 17 of offset knuckle 18 . 5 and the center-point of roller pin 36 of roller 32 and roller sleeve 35 are preferably length L 1 apart. Preferably, center-points comprise equivalent length L 1 of ⅜ inch; however, length L 1 may be between approximately ¼ inch and approximately ½ inches. Moreover, when in use, the greater length L 1 between center-points of rotatable hinge pin 17 and roller pin 36 of roller 32 and roller sleeve 35 results in an increased arc a of rotation of link 21 about stationary hinge pin 16 of offset knuckles 18 . 4 , which further results in an increased opposite force f of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions. Preferably, as arc a moves slightly, a 1 moves at much greater arc angle; thus, allows flat spring 22 to maintain optimum force f between inner-upper surface 49 and inner-lower surface 51 of flat spring 22 . The ratio of arc a to arc a 1 and equivalent force f are proportional to length L 1 .
Referring again to FIG. 5.3 , there is illustrated a side view of control motion hinge 10 shown in a hinge-mostly-open position. Preferably, as door D is pushed further open expands arc a 1 , rotatable hinge leaf 14 rotates further about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 , which slightly rotates link 21 about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 . It is contemplated herein that as arc a moves slightly, a 1 moves at much greater arc angle; thus, allows flat spring 22 to maintain optimum force f between inner-upper surface 49 and inner-lower surface 51 of flat spring 22 . First, when roller 32 reaches neutral point 52 of roller path 34 then arc a of rotation of link 21 about stationary hinge pin 16 of offset knuckles 18 . 5 has reached its maximum rotation (arc a is 38 degrees; however, arc a may be between approximately 15 degrees and 50 degrees) and inner-upper surface 49 and inner-lower surface 51 of flat spring 22 have reached the maximum distance of separation, which results in the maximum opposite force f of flat spring 22 to return inner-upper surface 49 and inner-lower surface 51 of flat spring 22 to their original positions. Second, when roller 32 reaches neutral point 52 of roller path 34 then arch a 1 in FIG. 5.2 the angle between plane 41 of stationary hinge leaf 12 and upper surface 44 of link 21 is comprise equivalent arc angle of 82 degrees; however, arc a 1 may be between approximately 60 degrees and 95 degrees. It should be recognized that force f can change arc a 1 in either direction to maximum angle of 110 degrees; however, arc a 1 may be between approximately 100 degrees and 180 degrees, or return arc a 1 to a closed position of 0 to −5 degrees. Third, when roller 32 reaches neutral point 52 of roller path 34 then upper surface 44 of link 21 lifts above upper exterior surface of offset knuckles 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 loads flat spring 22 . Moreover, when roller 32 reaches neutral point 52 of roller path 34 then roller 32 preferably climbs to the top of roller path 34 an altitude preferably of length L 3 (shown in FIG. 5.4 ), wherein door D reaches approximately eighty-two (82) degrees arc a 1 hold-open position of door D (other degrees are contemplated herein). Preferably, length L 3 comprise equivalent of 3/16 inch as shown; however, length L 3 may be between approximately 0 inch and approximately ⅜ inch.
Referring again to FIG. 5.4 , there is illustrated a side view of control motion hinge 10 shown in a hinge full-open position. Preferably, as door D is pushed to full open arc a 1 (approximately 110 degrees; however, arc a 1 may be between approximately 100 degrees and 180 degrees,) and rotatable hinge leaf 14 rotates still further about rotatable hinge pin 17 of offset knuckle 18 . 3 (similarly with 18 . 1 , 18 . 2 not shown) of rotatable hinge leaf 14 , which partially reverse rotates (opposite direction) link 21 about stationary hinge pin 16 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) of stationary hinge leaf 12 reduces arc a and force f; but, moves arc a 1 to maximum open angle of 110 degrees, however, arc a 1 may be between approximately 100 degrees and 180 degrees; thus allows roller 32 to traverse horizontally along hold-open ramp 54 of roller path 34 in a linear direction away from the center-point of stationary hinge pin 16 . Moreover, FIG. 5.4 illustrates additional measurements. The first is preferably the center-points between stationary hinge pin and rotatable hinge pin 17 , length L 4 . Preferably, length L 4 comprise equivalent of ⅝ inch as shown; however, length L 3 may be between approximately ⅜ inch and approximately ¾ inch. The second is preferably the travel distance of roller 32 from closed door to neutral point 52 of roller path 34 , length L 2 . Preferably, length L 2 comprise equivalent of ⅝ inch as shown; however, length L 2 may be between approximately ½ inch and approximately ¾ inch.
The dimensions referenced as preferred herein above are understood as one preferred configuration herein, and are not intended to be dimensions which are limiting in any way to other suitable configurations, door and jam configuration and/or weight of the applicable door being supported.
Hinge Close Cycle
Referring again to FIG. 5.4 , when door D is pushed to full open position (as shown) and in this position door D preferably is held in a hold-open position until door D is nudged closed wherein roller 32 traverses back past neutral point 52 , which releases force f of flat spring 22 , which results in roller 32 to traverse from hold-open ramp 54 to neutral point 52 to roller stop 38 of closing ramp 31 in a direction toward the center-point of stationary hinge pin 16 , which further causes rotatable hinge leaf 14 to return along arc a 1 until geometric plane 41 of rotatable hinge leaf 14 and stationary hinge leaf 12 contact or come in close proximate contact with one another.
Referring now to FIG. 5.5 , preferably when door D is in the closed position the weight of door D may place pull away force fd on flat spring 22 causes door D to possibly sag (door D pulls away and tilts down via pull away force fd as shown in FIG. 1 ); however, interior lip 19 of offset knuckle 18 . 5 (similarly with 18 . 4 not shown) combines with force f applied by flat spring 22 to prevent sag in door D and/or to prevent roller 32 from traversing roller path 34 . Moreover, roller 32 preferably is cradled in a pocket formed by roller stop 38 of roller path 34 and bottom edge 19 of offset knuckle 18 . 5 to hold rotatable hinge leaf 14 and stationary hinge leaf 12 in the shown closed position countering pull away force fd on door D.
It is contemplated that lengths L 1 , L 2 , L 3 , L 4 , a, and/or a 1 may be modified or one or more combinations may be modified to achieve increased force f, more or less door closing power, and/or to prevent sag of door D.
It is further contemplated that roller path 34 may be configured to have straight line(s) with or without sharp corners, or other contours, curves, and/or lengths to accomplish motions set forth herein or further contemplated for alternative control of motion hinge 10 .
It is contemplated that flat spring 22 may be modified, sized, derived from different materials and/or configured to achieve increased force and/or more or less door closing power.
It is contemplated that stationary hinge leaf 12 and rotatable hinge leaf 14 may flip positions.
Referring now to FIGS. 6 , 6 . 1 , and 6 . 2 , by way of example, and not limitation, there is illustrated a series of side views of control motion hinge 10 in motion, in accordance with an alternate embodiment of the present invention. Referring again to FIG. 6.1 , there is illustrated a side view of control motion hinge 10 , included is dampener 60 shown in a hinge-closed position with door D closed against jam J. Preferably, jam J is fitted with housing tube 65 offset from control motion hinge 10 and connected to jam J on first end 69 of housing tube 65 and approximately centered in jam J and preferably positioned along jam J other than where assembly H 1 , H 2 , and H 3 (as shown in FIG. 1 ) are located. Housing tube 65 preferably is ¾ inch in diameter, wherein such diameter hole is correspondingly drilled or otherwise defined into jam J to the preferred depth of 1.5 to 3 inches or alternatively into door D if stationary hinge leaf 12 and rotatable hinge leaf 14 flip positions. Jam J preferably includes hole 73 bored into jam J where housing tube 65 is positioned therein. Moreover, dampener 60 preferably includes plunger 62 and coil spring 64 . Preferably, plunger of dampener 60 passes in and out of housing tube 65 through which plunger 62 and plunger 62 preferably connects to coil spring 64 (shown in a compressed mode in FIG. 6.1 ) to smooth out or dampen the shock impulse and dissipate the kinetic energy of door D when closing. Housing tube 65 and plunger 62 are further preferably manufactured from aluminum, however, steel, plastic, fiberglass or other suitable material having characteristics, such as durability, water-resistance, lightweight, or the like, capable of providing structure to housing tube 65 and plunger 62 .
Referring again to FIG. 6.2 , there is illustrated a side view of control motion hinge 10 included is dampener shown in a hinge-open position with door D swung open from jam J. Plunger 62 preferably includes on one end striker head 61 and on the other end compression head 63 and travels in and out of housing tube 65 via rod seal 72 . Compression head 63 of plunger 62 is preferably attached to first end 66 of coil spring 64 and second end 67 of coil spring 64 is preferably attached to second end 68 of housing tube 65 , and housed therein. Moreover, coil spring 64 (shown in an expanded mode with rod 62 extends through hole 72 in FIG. 6.2 ) is preferably manufactured from hardened steel, however, stainless steel, plastic, or other suitable material having characteristics, such as shape memory, resistance, lightweight, or the like.
During door D closure cycle, rotatable hinge leaf 14 preferably returns along arc a 1 until geometric plane 41 of rotatable hinge leaf 14 contacts striker head 61 and transfers the kinetic energy of rotating door D to compression head 63 , which preferably is absorbed by coil spring 64 within housing tube 65 , resulting in geometric plane 41 of rotatable hinge leaf 14 preferably pushes plunger 62 towards second end 68 of housing tube 65 and compresses coil spring 64 , wherein rotatable hinge leaf 14 gently contacts or comes in close proximate contact with geometric plane 41 of stationary hinge leaf 12 for a soft closure of door D.
It is contemplated that dampener 60 may be configured as any dashpot or shock absorber whether pneumatic or hydraulic having common form of a cylinder with a sliding piston inside wherein the cylinder is filled with a fluid (such as hydraulic fluid) or air and designed to smooth out or dampen shock impulse, and dissipate kinetic energy or other known dampener known by one of ordinary skill in the art.
It is recognized that dampener 60 may be integrated within stationary hinge leaf 12 , rotatable hinge leaf 14 , or alternatively in door D.
It is further recognized that dampener 60 may encompass the features and functionality set forth in United States Non-provisional Application entitled “Door Hinge with a Hidden Closure System,” having assigned Ser. No. 12/012,690, filed on Feb. 4, 2008, incorporated herein by reference in its entirety.
The foregoing description and drawings comprise illustrative embodiments. Having thus described exemplary embodiments, it should be noted by those skilled in the art that the disclosures within are exemplary only, and that various other alternatives, adaptations, and modifications may be made within the scope of the present disclosure. Many modifications and other embodiments will come to mind to one skilled in the art to which this disclosure pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Although specific terms may be employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Accordingly, the present disclosure is not limited to the specific embodiments illustrated herein, but is limited only by the following claims.
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A control motion hinge, comprising a first leaf hinge with three knuckles to secure a first pin, wherein the two outer knuckles have roller knuckles, a link having a two knuckles on a first end to interlock with the first leaf hinge and a single knuckle on a second end, a second leaf hinge with two knuckles to secure a second pin when interlocked with the second end of the link, wherein the two knuckles of the second leaf hinge have a roller path for engaging the roller of the first leaf hinge, wherein such rollers traverse the roller path, and thus softly closing the door reducing the sound of closure during the final approach of the door.
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[0001] This invention was made in part with U.S. Government support under a grant from the Office of Naval Research Contract No. N000140010374. The U.S. Government has certain rights in this invention.
FIELD OF THE INVENTION
[0002] The present invention is directed generally to a method and system for monitoring oil properties. More particularly the invention is directed to a method and system using a contact potential sensor to monitor properties of flowing oil
BACKGROUND OF THE INVENTION
[0003] A variety of mechanical systems, such as engines, require means to monitor the quality of oil used for lubrication and other functionalities. A number of prior art methods exist for performing this function, including, for example (1) an odometer monitor to time out the useful life of oil based on general lifetime assumptions, (2) a magnetic field sensor for sensing density of ferromagnetic particles in the oil, (3) a particle separating device to evaluate size and number of contaminating particles, (4) a threshold oil temperature sensor, (5) a corrodable sensor which undergoes electrical circuit break down as oil breaks down or suffers contamination, (6) a chemical prediction device to assess acid content in the oil, and (7) a light absorption sensor based on light attenuation by particles in the oil.
[0004] The above described prior art systems suffer from numerous disadvantages, such as, gross insensitivity to critical operating conditions to which oil is subjected, inability to be utilized in many applications due to structural size or geometry limitations, inability to sense other than ferromagnetic debris in the oil, and too specific a measure of oil degradation thereby ignoring many other indicators of oil condition.
SUMMARY OF THE INVENTION
[0005] It is therefore an object of the invention to provide an improved system and method for monitoring the condition of an oil.
[0006] It is yet another object of the invention to provide an improved contact potential sensor for monitoring the condition of oil flowing in a system.
[0007] It is a further object of the invention to provide an improved method and system for sensing the dielectric properties of oil.
[0008] It is an additional object of the invention to provide an improved method and system utilizing a non-vibrating contact potential difference probe to monitor the properties of flowing oil and other dielectric media.
[0009] It is also an object of the invention to provide an improved method and system for establishing an electric field probe for sensing the dielectric properties of oil.
[0010] It is in addition an object of the invention to provide an improved method and system to characterize a changing contact potential to assess the ongoing condition of an oil undergoing use.
[0011] It is yet a further object of the invention to provide an improved system and method for monitoring properties of a fluid flowing past a contact potential difference sensor.
[0012] It is also another object of the invention to provide an improved method and system for separating molecules in a flowing fluid to characterize the condition of the fluid.
[0013] It is still a further object of the invention to provide an improved method and system identifying signatures associated with selected constituents of an oil undergoing degradation from use.
[0014] It is yet an additional object of the invention to provide an improved method and system to evaluate rate of degradation of oil and other fluids undergoing use in a system.
[0015] It is also a further object of the invention to provide an improved system and method for characterizing flowing oil, and other fluids or gases having a changing dielectric condition.
[0016] Further advantages and features of the present invention will be apparent from the following description of the drawings, specifications and claims illustrating the preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] [0017]FIG. 1 illustrates a schematic of a contact potential difference sensor;
[0018] [0018]FIG. 2 illustrates one form of electrical circuit for the sensor of FIG. 1;
[0019] [0019]FIG. 3 illustrates a system with a flow of oil past the contact potential difference sensor of FIG. 1;
[0020] [0020]FIG. 4 illustrates schematically the separation of molecular components of oil in the system of FIG. 2;
[0021] [0021]FIG. 5 illustrates a schematic plot of contact potential of oil measured by the sensor of FIG. 1 as a function of time of oil use;
[0022] [0022]FIG. 6 illustrates an example use of the contact potential difference sensor in an oil drain plug environment;
[0023] [0023]FIG. 7A illustrates contact potentials for selected time periods of unused oil flow through a system; and FIG. 7B illustrates contact potentials for a used oil undergoing flow through a system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] An illustration of the principals used to monitor properties of oils, other fluids and even particular gaseous environments is shown schematically in FIG. 1. A contact potential sensor 10 is illustrated wherein a first conductive material 20 , such as a first metal, is electrically coupled by a connection 25 to a second conductive material 30 , such as a second metal. In particular the sensor 10 is a non-vibrating contact potential difference probe. An electric field, {right arrow over (ε)}, arises between the first conductive material 20 and the second conductive material 30 when the two materials are electrically connected, and the electric field, {right arrow over (ε)}, will form when the Fermi energies of the two materials 20 and 30 are equilibrated. The strength of the electric field, {right arrow over (ε)}, will depend on the dielectric properties, a relative dielectric constant, ε r , of the material disposed in gap 35 between the two materials 20 and 30 . In general, the sensor 10 can operate to sense dielectric properties of fluids, such as oil, and even dense gases flowing past the sensor 10 .
[0025] The first and second conductive materials 20 and 30 when electrically connected compose an electrochemical cell, and an electrical current 110 will result if oil 46 and/or one of its constituents disposed between the materials 20 and 30 conducts electrical charge. As the oil 46 flows past the two surfaces of the materials 20 and 30 , the electrical field, ε, separates the charges of the oil 46 , the positive charges tending toward the negative surface and vise versa. The current density will depend on the interfacial electron transfer reactions of the oil 46 , and its constituents on the temperature and on the contact potential difference between the materials 20 and 30 . The current density can be written as:
i=K
1
TεK
2
{tilde under (ε)}/kT
[0026] where i is the current density (amperes/cm 2 ), K 1 is a constant, T is the temperature, K 2 is another constant, ε is the electrical field produced by the contact potential difference, and k is Boltzmann's constant. It can also be written that v, the number of ions per unit time striking the electrodes is:
V=i/F
[0027] where F is the Faraday's constant, and i is the current in circuit 38 having a circuit component 42 , such as an alarm indicator, display or the like and also can include a switch 44 (see FIG. 2).
[0028] [0028]FIG. 3 illustrates schematically the sensor 10 wherein oil 46 , containing molecules 45 , flow past the two materials 20 and 30 positioned within a pipe 50 . FIGS. 3 and 4 illustrate conceptually the separation of the oil molecules 45 which impinge on walls 60 and 65 of the materials 20 and 30 , respectively. A resulting contact potential V will then develop and is shown schematically in FIG. 5 as a function of time of oil use. The plot can yield signatures associated with the chemical or dielectric state of the oil 46 . Chemical changes can include degradation of the molecular makeup of the oil 46 and contamination by other materials in contact with the oil 46 . In the most general sense the sensor 10 can monitor any fluid or gas stream which yields an adequate contact potential for examination and analysis by a user.
[0029] A specific commercial illustration of the use of the sensor 10 is shown in FIG. 6. A section of an oil pan 70 includes a drain plug 80 in an automotive oil system. As the oil 46 moves in the vicinity of the sensor 10 and the dielectric properties change, the sensor 10 indicates a change which is manifested by the contact potential being measured.
[0030] [0030]FIGS. 7A and 7B illustrate experimental operation of the sensor 10 shown in FIGS. 1 - 3 . A conventional brand of new and used motor oil were monitored by the sensor 10 , and the results are shown in FIGS. 7A and 7B, respectively. A variety of important dielectric changes can be characterized in this manner and clearly illustrates the usefulness of the sensor 10 in monitoring a fluid, such as an oil, or other such characterizable material.
[0031] The illustrated sensor 10 has applications in any system having open or closed loops wherein a fluid can be passed by the sensor 10 enabling characterization of the dielectric properties of the fluid. Examples include, without limitation, automotive systems, chemical plants, selected high pressure gaseous environments, such as turbine environments, and environmental monitors.
[0032] These and other objects, advantages and features of the invention together with the organization and manner of operation thereof will become apparent from the following detailed description when taken into conjunction with the accompanying drawings wherein like elements have like numerals throughout the drawings.
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A method and system for contact potential sensing of dielectric properties of a fluid. The method and system include a contact potential sensor, an open or closed loop for passing a fluid past the sensor, measuring a contact potential to characterize dielectric properties of the fluid and outputting the dielectric property information for analysis and response thereto.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation application of application Ser. No. 12/778,315, filed May 12, 2010, U.S. Publication No. 2011-0278546 and published on Nov. 17, 2011.
FEDERAL RESEARCH STATEMENT
This invention was made with Government support under Government Contract No.: FA8650-08-C-7806 awarded by Defense Advanced Research Projects Agency (DARPA). The Government has certain rights in this invention.
FIELD OF INVENTION
The present invention relates to semiconductor nanowire tunnel field effect transistors.
DESCRIPTION OF RELATED ART
A nanowire tunnel field effect transistor (FET) includes doped portions of nanowire that contact the channel region and serve as source and drain regions of the device. The source region may include, p-type doped silicon material, while the drain region may include n-type doped silicon material.
BRIEF SUMMARY
According to one embodiment of the present invention, a nanowire tunnel field effect transistor (FET) device includes a channel region including a silicon portion having a first distal end and a second distal end, the silicon portion is surrounded by a gate structure disposed circumferentially around the silicon portion, a drain region including an n-type doped silicon portion extending from the first distal end, a cavity defined by the second distal end of the silicon portion and an inner diameter of the gate structure, and a source region including a doped epi-silicon portion epitaxially extending from the second distal end of the silicon portion in the cavity, a first pad region, and a portion of a silicon substrate.
According to another embodiment of the present invention, a nanowire tunnel field effect transistor (FET) device includes a channel region including a silicon portion having a first distal end and a second distal end, the silicon portion is surrounded by a gate structure disposed circumferentially around the silicon portion, a drain region including an n-type doped silicon portion extending from the first distal end, a portion of the n-type doped silicon portion arranged in the channel region, a cavity defined by the second distal end of the silicon portion and an inner diameter of the gate structure, and a source region including a doped epi-silicon portion epitaxially extending from the second distal end of the silicon portion in the cavity, a first pad region, and a portion of a silicon substrate.
According to yet another embodiment of the present invention, a nanowire tunnel field effect transistor (FET) device includes a channel region including a silicon portion having a first distal end and a second distal end, the silicon portion is surrounded by a gate structure disposed circumferentially around the silicon portion, a drain region including an doped silicon portion extending from the first distal end, a portion of the doped silicon portion arranged in the channel region, a cavity defined by the second distal end of the silicon portion and an inner diameter of the gate structure, and a source region including a doped epi-silicon portion epitaxially extending from the second distal end of the silicon portion in the cavity, a first pad region, and a portion of a silicon substrate.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
FIGS. 1-8 illustrate an exemplary method for forming a tunnel field effect transistor (FET) device.
DETAILED DESCRIPTION
FIGS. 1-8 illustrate a cross-sectional views of a method for forming a FET device. Referring to FIG. 1 , a silicon on insulator (SOI) layer 102 is defined on a buried oxide (BOX) layer 104 that is disposed on a silicon substrate 100 . The SOI layer 102 includes a SOI pad region 106 , a SOI pad region 108 , and a silicon nanowire 110 . A gate 112 is formed around a portion of the nanowire 110 , and capped with a capping layer 116 that may include, for example, a polysilicon material. A hardmask layer 118 such as, for example, silicon nitride (Si 3 N 4 ) is formed on the capping layer 116 . The gate 112 may include layers of materials (not shown) such as, for example, a first gate dielectric layer (high K layer), such as silicon dioxide (SiO 2 ) around the nanowire 110 , a second gate dielectric layer (high K layer) such as hafnium oxide (HfO 2 ) formed around the first gate dielectric layer, and a metal layer such as tantalum nitride (TaN) formed around the second gate dielectric layer.
FIG. 2 illustrates spacer portions 202 formed along opposing sides of the capping layer 116 . The spacers are formed by depositing a blanket dielectric film such as silicon nitride and etching the dielectric film from all horizontal surfaces by reactive ion etching (RIE). The spacer portions 202 are formed around portions of the nanowire 110 that extend from the capping layer 116 and surround portions of the nanowires 110 .
FIG. 3 illustrates the resultant structure following the implantation and activation of n-type ions in the SOI pad region 106 and the adjacent portion of the nanowire 110 that defines a drain region (D). The ions may be implanted by for example, forming a protective mask layer over the SOI pad region 108 and the adjacent nanowire 110 prior to ion implantation. Alternatively, the ions may be implanted at an angle such that the capping layer 116 and spacer 202 may absorb ions and prevent ions from being implanted in an undesired region.
FIG. 4 illustrates the resultant structure following the formation of a conformal hardmask layer 402 over the exposed surfaces of the device. The conformal hardmask layer 402 may include for example, silicon dioxide, silicon nitride, or any other sacrificial material that will inhibit epitaxial growth and may be easily removed.
FIG. 5 illustrates the resultant structure following removal of a portion of the nanowire 110 that extended between the SOI pad region 108 and the channel region of the gate 112 . The portion of the nanowire 110 may be removed by, for example, patterning and removing a portion of a portion of the conformal hardmask layer 402 and performing an etching process such as, for example, a wet chemical or vapor etching process that etches exposed silicon, and removes the exposed silicon nanowire 110 . The portion of the conformal hardmask layer 402 is removed using a process that preserves the conformal hardmask layer 402 in the region that will become the drain region (described below); the removal process is controlled to avoid compromising the integrity of the hardmask layer 118 over the gate 112 and the integrity of the spacer 202 .
FIG. 6 illustrates the resultant structure following an optional isotropic etching process may be performed to remove a portion of the nanowire 110 that is surrounded by the spacer wall 202 and the gate 112 to recess the nanowire 110 into the gate 112 , and form a cavity 602 defined by the gate 112 , the nanowire 110 and the spacer wall 202 . Alternate embodiments may not include the isotropic etching process that forms the cavity 602 . The lateral etching process that forms cavity 602 may be time based. Width variation in spacer 202 may lead to variations in the position of the edges of the recessed nanowire 110 . The etching rate in the cavity 602 depends on the size of the cavity, with narrower orifice corresponding to slower etch rates. Variations in the nanowire size will therefore lead to variations in the depth of cavity 602 .
FIG. 7 illustrates the resultant structure following the removal of an exposed portion of the BOX layer 104 that exposes a portion of the silicon substrate 100 .
FIG. 8 illustrates cross-sectional views of the resultant structures following a selective epitaxial growth of silicon to form a source region (S) 802 . The source region 802 is epitaxially grown in the cavity 602 (of FIG. 7 ) from the exposed nanowire 110 in the gate 112 to form the source region 802 . The source region 802 is epitaxially grown from the SOI pad region 108 and the exposed portion of the silicon substrate 100 . The source region 802 is formed by epitaxially growing, for example, in-situ doped silicon (Si), a silicon germanium (SiGe), or germanium (Ge) that may be p-type doped. As an example, a chemical vapor deposition (CVD) reactor may be used to perform the epitaxial growth. Precursors for silicon epitaxy include SiCl 4 , SiH 4 combined with HCL. The use of chlorine allows selective deposition of silicon only on exposed silicon surfaces. A precursor for SiGe may be GeH 4 , which may obtain deposition selectivity without HCL. Precursors for dopants may include B 2 H 6 for p-type doping. Deposition temperatures may range from 550° C. to 1000° C. for pure silicon deposition, and as low as 300° C. for pure Ge deposition.
Once source region (S) 802 is formed, the doping may be activated by, for example, a laser or flash anneal process. The laser or flash annealing may reduce diffusion of ions into the channel region 804 of the gate 112 , and result in a high uniform concentration of doping in the source region 802 with an abrupt junction in the nanowires 110 .
The hardmask layer 402 and 118 may be removed by, for example, a RIE process. A silicide may be formed on the source region 802 the drain region D and the gate region. Examples of silicide forming metals include Ni, Pt, Co, and alloys such as NiPt. When Ni is used the NiSi phase is formed due to its low resistivity. For example, formation temperatures include 400-600° C. Once the silicidation process is performed, capping layers and vias for connectivity (not shown) may be formed and a conductive material such as, Al, Au, Cu, or Ag may be deposited to form contacts.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one ore more other features, integers, steps, operations, element components, and/or groups thereof.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated
The diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention.
While the preferred embodiment to the invention had been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described.
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A nanowire tunnel field effect transistor (FET) device includes a channel region including a silicon portion having a first distal end and a second distal end, the silicon portion is surrounded by a gate structure disposed circumferentially around the silicon portion, a drain region including an doped silicon portion extending from the first distal end, a portion of the doped silicon portion arranged in the channel region, a cavity defined by the second distal end of the silicon portion and an inner diameter of the gate structure, and a source region including a doped epi-silicon portion epitaxially extending from the second distal end of the silicon portion in the cavity, a first pad region, and a portion of a silicon substrate.
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BACKGROUND OF THE INVENTION
[0001] This invention relates generally to a system for reclaiming face fibers and carpet backing from post-consumer carpet.
[0002] Carpet typically includes, face pile or face fiber and a backing system comprised of one or more polypropylene and/or polyvinylchloride (PVC) substrates and may have adhesive and/or latex adhesive backing for holding the face fibers in place.
[0003] Carpet that has been installed and subjected to use in residential, commercial, governmental, and industrial environments may be replaced from time to time, with the installed carpet being removed and disposed of Such carpet is known in the industry as “post-consumer” carpet, as the carpet has been subjected to the wear and tear of use. Although the reasons for removing such post-consumer carpet may vary from application to application, the magnitude of post-consumer carpet disposed of on an annual basis is considerable. It is estimated that billions of pounds of such post-consumer carpet is disposed of annually, typically in landfills, resulting in a significant consumption of landfill space. Accordingly, a reduction of such carpet waste would be desirable.
[0004] As such post-consumer carpet often times includes fibers, polymers, and other components that can potentially be reused, it would be desirable to have a system by which the reusable components of could be reclaimed, thereby reducing landfill deposits. In particular, it would be desirable to recycle from carpet typical constituents, such as nylon, polypropylene, carbon calcium, polyvinylchloride, PVC, etc., which, in addition to conserving landfill space would also conserve valuable natural resources and potentially provide significant cost savings.
SUMMARY OF THE INVENTION
[0005] Generally, the present invention includes in one preferred embodiment a system for reclaiming the face fibers and polypropylene backing material from rolls and flat pieces of post-consumer carpet. The system includes a separator for separating the face fibers from the polypropylene backing and the adhesives and/or latex coating ordinarily found on such backing. An extruder extrudes the face fibers separated from the polypropylene backing into extrusions, and a pelletizer pelletizes such extrusions. In one embodiment, a granulator chops and/or grinds or otherwise reduces the polypropylene backing into small bits, fragments, or particles, or chips, after separation of the face fibers therefrom. Also, a device is provided for separating off the adhesives and/or latex and for melting the polypropylene backing, through the application of heat and compaction forces.
[0006] More specifically, the present invention also includes a method and apparatus for reclaiming face fibers and polypropylene and/or polyvinyl chloride (PVC) backing from post-consumer carpet. The method may include, in one preferred embodiment, sorting rolls and/or sections of post-consumer carpet by face fiber type prior to separation of such fibers from the backing. An infrared sensor may be used for assisting in such sorting step. The impurities from the face fibers, after separation from the polypropylene backing, are preferably removed, and in one preferred embodiment, a willow cleaner is used for such removal of impurities from the polypropylene opened fibers. Further, the face fibers, after separation from the backing, and after having impurities removed therefrom, can be blended with additional fibers or constituents prior to being extruded in the extruder.
[0007] With regard to the polypropylene backing and/or PVC backing, such backing, after having the face fibers separated therefrom, and being processed through a grinder, granulator, shredder, and/or a cutter, are then melted through the application of heat and pressure, is allowed to cool and harden, and is then processed into particles, fragments, or bits. These bits can be used for subsequent processing and products, and could be, for example, molded into products through injection molding, rotational molding, etc., or could be sold or reused in flakes and/or chips and/or bits or particles as a commodity for use in other manufacturing and/or commercial applications.
[0008] The present invention also includes, in one embodiment, the face fibers, after separation, extrusion, and pelletization, being used in other manufacturing and/or commercial applications, such as for molding, e.g., composite molding, injection molding, rotational molding, etc., or for other manufacturing applications, such as spinning, extrusion, etc. Such pellets could also be sold on a commodity basis to industry for other manufacturing and/or commercial purposes.
[0009] A preferred embodiment of a system constructed in accordance with the present invention includes a separator that separates the face fibers from the latex-coated polypropylene backing and an extruder that extrudes the face fibers into extrusions. A roller opener device opens the fibers of the backing to yield opened polypropylene portions. Alternately, a pelletizer machine pelletizes the extrusions, and a granulator chops the latex-coated polypropylene backing into particles, fragments or bits. Also, a heat source, which could be electric resistance heat, gas-fired heat or heat from another combustion source, solar heat, microwave energy, chemical reaction heat, etc., is provided that heats the bits sufficiently to generally melt the bits and sufficiently to generally separate, cook off, bake off, volatize and/or otherwise remove the latex therefrom.
[0010] The present invention further contemplates alternate embodiments, specifically including baling the polypropylene backing after being opened with a roller opener and/or chopped and ground in the granulator, and then disposing of such bales in a landfill. This embodiment allows for easier material handling and lower disposal volume as compared to disposing of post-consumer carpet intact. Alternately, such bales of polypropylene, latex, and/or PVC material could be sold to subsequent converters for use in other products.
[0011] In another embodiment of the present invention, such polypropylene backing material can be baled after such opening with a roller opener and/or chopping and grinding in the granulator, and then such bales subsequently opened through use of opening equipment, such as textile opening equipment, wherein such baled material is shredded, torn, and subjected to dust removal. The resulting fiber remains can be used in non-woven products, for example, singularly, or blended with other fibers, for production of non-woven products, such as insulation, sound deadening panels of other materials, batting, filler, under carpet pads, floor tiles, furniture, industrial applications such as roofing material mixed with asphalt, etc. Depending on the desired production layout, it may be possible to eliminate the baling step altogether, such that the backing with the adhesives and/or latex, after chopping and grinding, is next subjected to the opening process without the intervening baling step.
[0012] The present invention also includes a roller opener for reclaiming material from carpet backing, the roller opener including an intake that receives the carpet backing and an opener roll. A plurality of working rolls are provided adjacent the opener roll and are configured for forming at least one nip zone between the working rolls and the opener roll. At least one motor drives the opener roll and the working rolls, and the opener roll and the working rolls are configured to open the carpet backing into fibrous portions in the nip zone.
[0013] The roller opener may further include a conveyor and/or a suction receiver that receives and transports the fibrous portions. Additionally, an inclined conveyor may be provided that transports the carpet backing to the intake of the roller opener.
[0014] Fibers can also be subjected to high pressure air, condensers, and/or a self-contained ultrasonic cleaning system which uses fluid for ultrasonically cleaning the fibers. The fibers can thereafter be subjected to drying and transported for extrusion, baling, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The foregoing, as well as other objects of the present invention, will be further apparent from the following detailed description of the preferred embodiment of the invention, when taken together with the accompanying specification and the drawings, in which:
[0016] FIG. 1A is a schematic representation of a first embodiment of a carpet reclamation system constructed in accordance with the present invention illustrating carpet backing, after the fibers are separated therefrom, being fed to a granulator;
[0017] FIG. 1B is a schematic representation of a second embodiment of a carpet reclamation system constructed in accordance with the present invention illustrating carpet backing, after the fibers are separated therefrom, being fed to a roller opener machine, the output of which being fed to a conveyor;
[0018] FIG. 1C is a schematic representation of a third embodiment of a carpet reclamation system constructed in accordance with the present invention illustrating carpet backing, after the fibers are separated therefrom, being fed to a roller opener machine, the output of which being fed through ducts;
[0019] FIG. 2 is a process flow diagram of a carpet reclamation system constructed in accordance with the present invention;
[0020] FIG. 3A is a side elevational view of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-down into a separator, the face fibers are separated from the backing and drawn away via suction, and the backing is drawn away by a conveyor belt;
[0021] FIG. 3B is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-down into a separator, the face fibers are separated from the backing and dropped downwardly onto a moving conveyer belt, and the backing is drawn away by a conveyor belt;
[0022] FIG. 3C is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-up into a separator, the face fibers are separated from the backing and drawn away via a conveyor belt, and the backing is drawn away by a conveyor belt;
[0023] FIG. 3D is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-up into a separator, the face fibers are separated from the backing and drawn away via a conveyor belt, and the backing is drawn away by a conveyor belt, and suction is applied to the backing carried by the conveyor belt;
[0024] FIG. 3E is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-up into a separator, the face fibers are separated from the backing and drawn away via a conveyor belt, and the backing is drawn away by a generally horizontal conveyor belt and fed to a roller opener machine;
[0025] FIG. 3F is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-up into a separator, the face fibers are separated from the backing and drawn away via a conveyor belt, and the backing is drawn away by a generally angled conveyor belt and fed to a roller opener machine;
[0026] FIG. 3G is a side elevational view of one preferred embodiment of a carpet reclamation system constructed in accordance with the present invention, wherein post-consumer carpet is fed face fiber side-up into a separator, the face fibers are separated from the backing and drawn away via a conveyor belt and then to a suction feed, and the backing is drawn away by a generally angled conveyor belt and fed to a roller opener machine;
[0027] FIG. 4 is plan view of a carpet reclamation system constructed in accordance with the present invention;
[0028] FIG. 5A is a perspective view of a first embodiment of a roller opener machine constructed in accordance with the present invention having a conveyor discharge;
[0029] FIG. 5B is a perspective view of a second embodiment of a roller opener machine constructed in accordance with the present invention having a suction discharge;
[0030] FIG. 6A is a left side elevational view of the roller opener machine constructed shown in FIG. 5A ;
[0031] FIG. 6B is a left side elevational view of the roller opener machine shown in FIG. 5B ;
[0032] FIG. 7A is a right side elevational view of the roller opener machine shown in FIG. 5A ; and
[0033] FIG. 7B is a right side elevational view of the roller opener machine shown in FIG. 5B .
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0034] The foregoing, as well as other objects of the present invention, will be further apparent from the following detailed description of the preferred embodiment of the invention, when taken together with the accompanying drawings and the description which follows set forth this invention in its preferred embodiment. However, it is contemplated that persons generally familiar with fiber reclamation will be able to apply the novel characteristics of the structures illustrated and described herein in other contexts by modification of certain details. Accordingly, the drawings and description are not to be taken as restrictive on the scope of this invention, but are to be understood as broad and general teachings.
[0035] Referring now to the drawings in detail, wherein like reference characters represent like elements or features throughout the various views, the carpet reclamation system of the present invention is indicated generally in the figures by reference character 10 .
[0036] Turning to FIG. 1A , one preferred embodiment of carpet reclamation system 10 is shown. Post-consumer carpet (shown in FIG. 1A for example purposes in the form of rolls, generally R, supported for rotation on a support), such as broadloom carpet or other carpet, is fed in the direction of arrow A 1 to a fiber separation machine, generally S. It is to be noted that in addition to post-consumer carpet in the form of rolls being fed into separation machine S, post-consumer carpet, or other carpet, in other forms, such a pieces, carpet area rugs, sections, tiles, squares, modular carpet, etc. (not shown) could also be fed into separation machine S individually manually and/or automatically. For example, modular carpet, carpet squares and/or carpet tiles could be fed into separation machine S single file, in multiple lateral and/or longitudinal rows (with respect to the direction of travel of such squares or tiles), in rows, random and/or intermittent groupings, etc. Separation machine S could be a Linta fiber separator, as manufactured by Linta Srl of Italy, although it is to be understood that other fiber separating machines could be used without departing from the disclosure of the present invention. It should be noted that carpet squares and/or tiles generally have a polyvinyl chloride (PVC) backing.
[0037] In the separation machine, or separator S, the face fibers, generally F, of a length of carpet, generally C, are separated from the backing, generally B, of carpet C. Although backing B used in connection with carpet C can be of various compositions, in one preferred embodiment, backing B is polypropylene having a latex coating thereon. A length of carpet C is fed into separator S with, as shown in FIG. 1A , the face fiber F side of carpet C facing downwardly. It is to be understood, however, that carpet C can be fed into separator S with face fiber F facing up, if desired, as shown in FIGS. 1C and 3C through 3 G.
[0038] In one preferred embodiment, a dedusting system, generally D, ( FIG. 3C ) is provided which directs high pressure air against carpet C during the feeding of the carpet C into the separator S.
[0039] A roller 16 having brushes 18 thereon which engage face fibers F of carpet C to assist in propelling carpet C beneath a guide bar 20 and onward to presentation to a circulating knife blade, generally 24 . Knife blade 24 is preferably continuously sharpened with a sharpening device (not shown) and cooled such that it does not overheat and such that it continuously presents a sharp cutting edge to sever face fibers F from backing B. As shown in FIG. 3C , two rollers 16 with brushes 18 can be provided, if desired, with one roller being above carpet C and the other roller contacting carpet C from below.
[0040] In one preferred embodiment, at least one roller has brushes and another roller 16 does not. For example, in FIG. 3C , the roller 16 on the upper side, i.e., on the side of the fiber pile of carpet C, and could have brushes, and the roller on the bottom, or backing, side of carpet C could be a roller 16 without brushes. Alternately, this configuration could be reversed, with the brushed roller 16 being on the bottom side, and the non-brushed roller being on the upper side of carpet C.
[0041] As shown in the FIG. 1A embodiment, after face fibers F are separated from backing B, they are sucked into a chute, or plenum, 28 , and then follow arrows A 2 to a baling operation wherein a bale press ( FIG. 4 ) is used, if desired, to form a package, or bale, of fibers, generally 32 , from fibers F. In this case, such bales 32 would subsequently be opened, i.e., the fibers removed from the bales 32 , and subjected to a suction flow, wherein the detached fibers are pulled into a hopper 36 of an extruder, generally E. Alternately, face fibers F can be separated from backing B, suctioned through chute 28 , and presented to hopper 36 without being baled in the interim, if desired. It is to be understood that packages or bales 32 could be of any desired shape and are not limited to the generally rectangular shape illustrated.
[0042] Upon being fed into extruder E, fibers F are compacted and forced to flow through spinneret and/or die, generally 38 , at the outlet of extruder E, which forms extrusions, such as extruded rods, bars, etc., generally 40 , from the melted face fibers F. A cutter, and/or pelletizer, shown functionally and designated generally as P, then cuts extrusions 40 into pellets 42 . Such pellets can be used in subsequent manufacturing processes and are preferably of relatively high quality polymer, such as nylon, olefin, polyester, acrylic, etc. Such polymer pellets 42 can be used, for example, in molding operations for injection molding, composite molding, rotational molding purposes, and/or for other purposes such as being reformed into fibers through re-melting and passing through a spinneret, etc. Such pellets could also be sold and traded as a commodity on a raw material basis for use in other manufacturing, industrial, and/or commercial applications.
[0043] FIG. 1A also illustrates the separation of backing B of carpet C from face fibers F and the subsequent processing of backing B. Backing B, alter having face fibers F separated therefrom, in one embodiment may pass through a shredder, cutter, chopper, granulator, etc., referred to herein collectively as a granulator, generally G. Either polypropylene or PVC backing can by passed directly to granulator G from separator S, if desired.
[0044] Granulator G includes cutters, generally 50 , which chop and/or grind backing B into flakes, chips, fragments, bits, or particles, generally 54 , which, as indicated by arrow A 3 , can be compressed and formed into bales 56 using a bale forming machine, or bale press, ( FIG. 4 ) although it is to be understood, as discussed above, that portions, fragments, bits, pieces, chips or particles 54 can by-pass the bale forming step and pass, unbaled, to an opening and dedusting step, wherein the pieces 54 are shred, torn, and/or subjected to dust removal and ultimately become fibers and/or fibrous material finding particular use as fibers to be blended in a non-woven article and/or material production line.
[0045] If desired, however, after baling, pieces 54 can be sold in bale form 56 to be subsequently used in other processes and/or products, deposited in a landfill or otherwise disposed of. Even if such bales are disposed of in a landfill, the amount of landfill volume consumed by such de-fibered backing material alone, when in a compressed and/or baled configuration, would be significantly less than if such post-consumer carpet had been dumped in the landfill without performing fiber reclamation and fiber compression as contemplated by the present invention.
[0046] FIG. 2 illustrates carpet reclamation system 10 in the form of a process chart. The initial step 62 includes post-consumer carpet being received by a facility. Such post-consumer carpet, as noted above, is carpet which has already been subjected to use in an installation or is otherwise not virgin carpet. Such post-consumer carpet could come from a variety of commercial, industrial, governmental, residential, etc. sources. After receipt at the facility, the post-consumer carpet is sorted in step 64 by face fiber type to facilitate fiber reclamation of similar types of face fiber during a particular batch reclamation process. As noted above, carpet typically includes, generally, face pile or face fiber and a backing system comprised of a polypropylene substrate with latex adhesive backing for holding the face fibers in place. In one preferred embodiment, carpet rolls R and/or carpet pieces are automatically transported to fiber separation machine S through use of conveyors, robots, tracks, or other suitable material handling devices.
[0047] It is to be understood that step 64 could include the use of an infrared sensor (not shown), such as an infrared spectrometer, which assists in classification of the post-consumer carpet face fiber prior to reclamation. When using such a sensor, and a Fourier transform process, an infrared spectra may be produced based on a particular piece of post-consumer carpet. Such produced spectra is then compared with a library of infrared spectra of other known materials, and this comparison can ultimately yield the chemical structure of the post-consumer carpet face fiber in order to facilitate sorting thereof. For example, post-consumer carpet may be sorted by face fiber type, which could be Nylon 6, Nylon 66, polyester, polypropylene, etc.
[0048] For carpet 65 having fibers wherein it is desirable and/or advantageous to separate face fibers F from backing B, such fibers F are so separated in step 66 . In the case of other carpets 66 , the fibers and backing of such carpets are opened together and dedusted in step 65 b , which could include use of roller opener 200 and/or granulator G. This combination of fibers from the backing and pile fibers may then be compressed by a press in step 65 c and baled. Alternately, such combined hacking and pile fibers may proceed to a storage and blending box 68 .
[0049] The fibers F separated from carpet 65 are dedusted and/or cleaned in step 68 , which may include use of a willow cleaner, and then are transported on to a holding and/or storage and blending box 72 . From box 72 , the fibers F may be fed in step 73 to extruder E, and then any needed components, chemicals, agents, formulations, etc. may be added in step 74 and extrusion conducted in step 76 . Subsequently, the extruded material may be cut into pellets or some other configuration in step 78 , resulting in relatively high quality polymer, which can subsequently be sold in bulk, molded, spun, etc.
[0050] Alternately, after the dedusting step 68 , fibers F can be compressed into bales in step 82 and sold in the form of nylon fiber bales. It is to be understood that the bales could be of some other fiber, if desired. Also, the fibers F could be subjected to cleaning, such as by high pressure air, condensers, and/or a self-contained ultrasonic cleaning, as discussed below.
[0051] Returning to the fiber separation step 66 , after fiber separation, backing B may be subjected to opening and dedusting step 65 b . The backing portions and/or fibers output from step 65 a may then follow steps 65 b , 65 c and 65 d , discussed above, and/or pass to the holding and/or storage and blending box 72 . From box 72 , the backing portions and/or fibers may be formed into a web in step 86 and thermobonded in step 88 for use products such as under carpet and/or mattress insulation pads in step 90 .
[0052] Alternately, from box 72 , the backing portions and/or fibers may be subjected to density compacting and melting in step 92 , and the granulated in step 94 for output as relatively low quality polymer 96 suitable for processes such as composite molding, injection molding filler, rotational molding, and/or sale as flakes.
[0053] Returning to step 92 , such density compaction and melting of the backing portions (polypropylene, PVC, etc.) and/or fibers may involve use of a conglomerator, generally 97 ( FIG. 4 ), such as manufactured by Italrec Srl of Italy. During this step, the backing portions and/or fibers are heated using a heat source, which could be electric resistance heat, gas-fired heat or heat from another combustion source, solar heat, microwave energy, chemical reaction heat, etc., provided conglomerator 97 for inputting heat thereto, such heat serving to melt the material into a flowable state. The latex and other adhesive components still remaining on the material are essentially baked off, cooked off, volatized and/or otherwise removed therefrom from the heat input by the heat source, thereby purifying such material. The melted mass of material exiting conglomerator 97 is then allowed to cool and is subsequently granulated in step 94 , resulting in polymer 96 .
[0054] FIG. 3A illustrates separator S separating face fibers F from backing B of carpet C. In the embodiment illustrated in FIG. 3A , carpet C is fed fiber side down through use of intake roller 16 having brushes 18 thereon, and also through use of a conveyor, generally 100 . As fibers F are separated from backing B, they are subjected to a suction flow downwardly through chute or plenum 28 , and carpet backing B is carried away via a conveyor 102 .
[0055] FIG. 3B illustrates an alternate embodiment separator S 1 , wherein carpet C is also fed face fiber side down. However, upon separation of face fibers F from backing B, face fibers F fall downwardly through a chute 104 via gravity and/or suction being applied thereto, and are collected on a conveyor 106 for transport away from separator S 1 .
[0056] FIG. 3C illustrates a second alternate embodiment, wherein carpet C is fed face fiber side up to separator S 2 . Rollers 16 having brushes 18 can be positioned for engaging and propelling backing B of carpet C, and/or, positioned above carpet C such that brushes 18 engage face fiber F to assist in propelling carpet C towards the cutting blade of separator S 2 . After being separated from backing B, face fibers F are carried away via a conveyor 108 , and backing B passes through a chute 110 and then engages a conveyor 112 where it is carried from separator S 2 .
[0057] FIG. 3D illustrates another alternate embodiment, wherein carpet C is also fed face fiber side up. A vacuum deduster, generally 120 , is provided to remove dust and particles from backing B as back B is transported by conveyor 112 .
[0058] FIG. 3E illustrates yet another alternate embodiment of system 10 , wherein carpet C is also fed to the separator face fiber side up. A roller opener, generally 200 , is provided which receives backing B from conveyor 112 and opens backing B into fibrous portions and simultaneously removes dust from such fibrous portions. Conveyor 112 is at approximately the same elevation as the input 202 of roller opener in this embodiment. The fibrous portions are output by roller opener 200 to a conveyor 204 for transport to further processing.
[0059] FIG. 3F illustrates still another alternate embodiment of system 10 , wherein carpet C is also fed to the separator face fiber side up. Roller opener 200 receives backing B from an upwardly inclined conveyor 208 , which in turn receives backing B from conveyor 112 .
[0060] FIG. 3G illustrates another alternate embodiment of system 10 , wherein carpet C is also fed to the separator face fiber side up. Roller opener 200 receives backing B from conveyor 208 , which in turn receives backing B from conveyor 112 . Fibers F are transported, after separation from carpet C, via a conveyor 108 to a suction input 210 and transported therefrom pneumatically by blower 212 . The fibrous portions discharged from roller opener 200 are also transported pneumatically through chute 214 .
[0061] FIGS. 1B , 1 C, 3 E, 3 F, 3 G, 4 , and 5 A through 7 B illustrate use of a roller opener device 200 in addition to, or instead of, granulator G in system 10 for processing backing B. Roller opener 200 , as shown in FIG. 1B , is inserted in place of granulator G ( FIG. 1A ) downstream of separator S, and processes backing B into opened fibrous portions which are deposited on a conveyor. Such fibrous portions are dedusted in roller opener 200 and can be compressed into bales or transported to subsequent processing, such as for formation into a web and/or compacted and melted and ultimately formed into chips, as discussed above and as shown in FIG. 2 . In FIG. 1B , the input 202 of roller opener 200 is at generally the elevation of the output of backing B of separator S.
[0062] FIG. 1C illustrates another preferred embodiment of system 10 , wherein roller opener 200 is positioned at a generally lower elevation than separator S, and with carpet C being fed into separator S with the pile, or face fiber, side facing upwardly. Backing B moves generally downwardly after separation of fibers F and flows into the input 202 of roller opener. Fibrous portions of backing B are drawn or propelled outwardly by positive air flow or a vacuum being drawn through discharge chutes, or suction condensers, 206 , and, as discussed above with respect to the embodiment in FIG. 1B , can be compressed into bales or transported for further processing.
[0063] FIG. 4 illustrates the machinery and process layout of one preferred embodiment of the carpet reclamation system 10 constructed in accordance with the present invention. Process lines include a nylon extrusion and palletizing line, generally NEP, a nylon fiber press line, generally NP, an agglomeration line, generally AGG, a polypropylene and/or PVC fiber press line, generally PFP, and a nonwoven line, generally NW.
[0064] Turning first to the nylon extrusion and pelletizing line NEP, carpets which have been sorted to select out those carpets with nylon pile fibers, or face fibers, are fed into the fiber separator S, and nylon face fibers separated from the carpet are pneumatically transported to a holding and/or storage and blending box, generally 130 , and then on to extruder E where they are extruded. The extrusions produced by extruder E are transported to pelletizer P, and then on to a pellet collection device 132 , where the pellets are loaded into Gaylord containers, bags, boxes, etc. for subsequent sale or use.
[0065] Alternately, the fibers can also be subjected to high pressure air, condensers, and a self-contained ultrasonic cleaning system, generally U, which uses fluid for ultrasonically cleaning the fibers, the fluid having a fluid cleaning system for extracting trash and/or debris therefrom. Additionally, the fibers can thereafter be subjected to drying, which may include forced-air being directed towards the fibers and/or heat being applied to the fibers and/or centrifugal drying of the fibers. The fibers can then be transported for baling, to extruder E for extrusion, etc.
[0066] Nylon fiber press line NP also receives nylon face fibers from sorted carpets, such fibers being separated from the carpets by separator S. The fibers may be transported to a self-contained ultrasonic cleaning system, generally U, and then to a deduster and fiber bale press, generally, 134 where they are dedusted and baled into bales or subsequent sale or use. Alternately, the fibers can be transported directly from separator S to deduster and fiber bale press 134 .
[0067] Agglomeration line AGG includes separator S, which separates the backing from sorted carpet, the backing then proceeding to roller opener 200 (discussed in more detail below), or to granulator G, shredder, cutter, etc. (not shown in FIG. 4 ). The backing is opened and is cleaned and/or dedusted in roller opener 200 , resulting in fibrous portions, typically polypropylene, as such material is commonly used for backing. The fibrous portions are subjected to density compaction and melting in conglomerator 97 and then to a granulator 140 for formation into chips. From granulator 140 , the chips are transported to a chip collection device 142 , where the chips are baled or loaded into Gaylord containers, bags, boxes, etc. for subsequent sale or use.
[0068] Polypropylene fiber press line PPP includes roller opener 200 and condensers 206 , where the backing is opened into such fibrous portions and cleaned and/or dedusted. The fibrous portions then preferably pass to willow cleaners 136 for further cleaning and/or dedusting. Preferably, willow cleaners 136 include condensers, shakers, and also, an adjustable knife to remove more or less trash and/or debris from the fibrous portions. Ducting for pneumatic transport of the fibrous portions exiting roller opener 200 carries the fibrous portions, to a fiber press, generally 144 , where such backing fibers, typically polypropylene, are pressed and baled for subsequent sale or use in further processing operations.
[0069] For reclamation of PVC backing ordinarily used on carpet squares and/or carpet tiles, such backing, once separated by separator S, may be transported to granulator G, and then to fiber press 144 , where such PVC backing fibers are pressed and baled for subsequent sale or use in further processing operations.
[0070] Nonwoven line NW can find particular use for carpets that have not been sorted and/or which are not readily sortable into particular face fiber and/or backing types. Line NW includes presenting such carpets to roller opener 200 and pneumatically transporting fibrous portions containing both face fibers and backing fibers from opener 200 through condensers 206 to willow cleaners 136 , and then to storage and blending box 138 where blending of the fibrous portions may occur as desired. From storage and blending box 138 , the fibers proceed, such as by pneumatic conveyance, to a nonwoven production machine, generally 148 .
[0071] Alternately, after passing through willow cleaners 136 , the fibrous portions can also be subjected to high pressure air, condensers, and a self-contained ultrasonic cleaning system U, discussed above, for extracting trash and/or debris from the fibrous portions. Additionally, the fibrous portions can thereafter be subjected to drying, which may include forced-air being directed towards the fibrous portions and/or heat being applied to the fibrous portions and/or centrifugal drying of the fibrous portions. The fibrous portions can then be transported to nonwoven production machine 148 .
[0072] In one preferred embodiment of the carpet reclamation systems of the present invention reclaim, or recycle, post-consumer carpets up to 12 feet wide, and in another preferred embodiment, carpet between one foot and 10 feet wide.
[0073] Turning to FIGS. 5A through 7B , preferred embodiments of roller opener 200 are illustrated in various views. Roller opener 200 includes a frame, generally FR, having a housing, generally H, with an intake 202 which includes an intake conveyor 220 having rolls 220 a and 220 b . A nip zone is formed at conveyor roll 220 b and an intake roll 224 of machine 200 . Backing B from carpet C is drawn into this nip zone and is thereafter worked between a plurality of nip zones between working rolls 226 a , 226 b , 226 c , 226 d , and 226 e and a main roll 230 .
[0074] As shown in FIG. 7A , roll 226 a is driven, together with intake roll 224 , by a motor M 1 , and roll 226 b and roll 220 b are driven by a motor M 2 . Rolls 226 c , 226 d , and 226 e are driven by motor, generally M 3 , and main roll 230 is driven by motor M 4 (FIG. 6 A). Drive members, generally 227 , such as belts, chains, gears (not shown), etc, can be used to transfer power from the motors to the respective rolls which they drive.
[0075] As the backing B is transported about main roll 230 and working rolls 226 a - e , backing B is shredded and reduced to fibers and fibrous portions. Main roll 230 and working rolls 226 may include fiber engaging textures such as teeth, wire clothing, etc., as is found in textile fiber carding machines. Simultaneously, dust, dirt, debris, etc. and/or carpet backing constituents, such as carbon and calcium dust, are extracted from backing B by suction being applied to the area of rolls 226 a - e , 230 and/or by gravity. Fibers and fibrous portions exiting the working area of rolls 226 a - e and 230 are then allowed to fall by gravity to output conveyor 204 for transport to the various lines as discussed above, or to a collection area for storage for subsequent use and/or disposal.
[0076] FIGS. 5B , 6 B, and 7 B illustrate an alternate embodiment roller opener 200 A, which is essentially the same as roller opener 200 , except roller opener 200 A includes a pneumatic discharge for transporting fibers and fibrous portions after backing B has been worked by rolls 226 a - e and main roll 230 . A centrifugal blower, generally 240 , is provided for suctioning off backing fibers and fibrous portions from the working area of rolls 226 a - e and roll 230 . A suction plenum, generally 242 , is provided having suction receivers, or condensers, 206 with transitions 244 for coupling to ducts 246 to transport the fibers and fibrous portions for subsequent processing, transport, collection and/or use.
[0077] From the foregoing, it can be seen that the present invention provides a system for reclaiming reusable fibers from carpets on an automated production basis.
[0078] While preferred embodiments of the invention have been described using specific terms, such description is for present illustrative purposes only, and it is to be understood that changes and variations to such embodiments, including but not limited to the substitution of equivalent features or parts, and the reversal of various features thereof, may be practiced by those of ordinary skill in the art without departing from the spirit or scope of the following claims.
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A method an apparatus for reclaiming face fibers and polypropylene and/or polyvinyl chloride backing material from rolls and pieces of post-consumer carpet. The system includes a separator for separating the face fibers from the backing and for separating latex and carbon calcium powder from polypropylene backing. An extruder is provided for extruding the face fibers separated from the backing into extrusions, and a pelletizer pelletizes the extrusions. A roller opener opens the polypropylene backing into fibrous portions and also cleans such fibrous portions. Alternately, a granulator can be provided that chops and grinds the polypropylene or PVC backing into fragments after the separation of the face fibers from the backing. A heat source heats the PVC fragments, and also the polypropylene fragments (thereby separating the latex therefrom), and ultimately melts such fragments. Reclaimed fibers can be pelletized, made into extrusions, used in non-woven products and in other manners.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a semiconductor module with a housing, a semiconductor component that is surrounded by the housing, and an integrated temperature sensor and interrupt device housed in the housing.
[0003] This type of semiconductor component can have any construction; i.e. it can be an MOS (Metal Oxide Semiconductor) transistor, an IGBT (Insulated Gate Bipolar Transistor), a JFET (Junction Field Effect Transistor), a thyristor, and so on. The structure and function of such semiconductor components are known from multiple sources, so that it is unnecessary to provide a detailed description of these semiconductor components here. The exemplary semiconductor component herein is a field-effect-controlled power MOS transistor, also known as a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), although the invention is not limited to this semiconductor component.
[0004] When semiconductor components such as power MOSFETs are utilized, the possibility of an error or failure can never be completely ruled out. Minor errors, which have almost no effect on the function of the semiconductor component, are distinguishable from serious errors, which cause functional impairment, and which in extreme cases, cause destruction of the power MOSFET. A particularly serious error is what is known as alloying-through or melting of a power MOSFET. In a MOSFET that is constructed as a high-side switch, a short can occur between the positive supply potential and the output terminal. In a MOSFET that is constructed as a low-side switch, the output terminal can be shorted to the device ground. The shorted load current of the respective power MOSFET can no longer be controlled by its drive logic. Thus, the load current is limited only by the impedance of the load and the defective transistor in the load circuit.
[0005] If a MOSFET is melted through and therefore shorted, the current flow is uncontrolled, and is determined by the voltage source and the resistances of the load and the melted MOSFET. The current is therefore smaller than in normal operation, and the fuse does not trip. The maximum power loss at the destroyed MOSFET occurs when its resistance reaches the order of magnitude of the load resistance. A voltage shearing between the MOSFET and the load then occurs, i.e. a matching for power transfer, or a power maximum. Depending on the size of the load resistance and the possibilities for cooling the melted, nonfunctional MOSFET, this leads to an extreme temperature rise of the MOSFET and ultimately the MOSFET or the chip environment will catch on fire.
[0006] As a precaution against overheating, a temperature sensor is typically provided, which switches the power MOSFET off given excessive overheating of the power MOSFET, for instance, as a consequence of a short-circuit current. But such a remedy only works as long as the power MOSFET is not defective. Besides this, the problem with this type of arrangement is that, in a semiconductor module with a plurality of power MOSFETs, it is extremely difficult technically to place a temperature sensor in the vicinity of such a MOSFET. Furthermore, it is disadvantageous to utilize a single temperature sensor that detects the temperature of the entire semiconductor module, because due to the poor heat conductivity inside the housing, the temperature sensor only senses an overtemperature after a long delay. Therefore, an overtemperature of a defective power MOSFET is only detected by the temperature sensor when the MOSFET is already disabled.
[0007] Beyond this, even in protected circuits such as this, extreme conditions occur, which can cause damage to the power MOSFET. The injury to the power MOSFET can manifest itself in the flowing of an uncontrollable load current though the power MOSFET and the presence of a forward bias at the drain and source terminals. The problem with this is that the power MOSFET can go out of control while remaining fully functional and continuing to conduct the short- circuit current. The current flow through the load circuit of the power MOSFET is not even stopped when the power MOSFET and the motherboard on which the power MOSFET is disposed is heated above the melting point of the solder, for instance above 250° C. If the heating continues, for instance above 300° C., the MOSFET is still not destroyed, but merely damaged. This effect is particularly serious when the heating of the power MOSFET and its environment is not abrupt, but rather occurs relatively slowly over several minutes. The power MOSFET and its environment can heat up progressively until the environment ignites and a fire starts.
[0008] Furthermore, a malfunction may not necessarily always be due to a short circuit. Rather, uncontrollable errors comparable to the errors just described can already occur given a nominal load current and a defective semiconductor component.
[0009] Issued German Patent DE 198 05 785 C1 describes a power semiconductor module that irreversibly interrupts the load circuit in case of an impermissible heating of the load circuit of a power semiconductor component. To accomplish this, interruption means are provided, which exhibit a volume expansion property in the case of an impermissibly high temperature, and which force open the load terminals and thus interrupt the load circuit in a defined and irreversible manner when a temperature threshold is crossed.
[0010] The interruption means described in Issued German Patent DE 198 05 785 C1 is problematic with respect to finding suitable materials that respond precisely at the desired temperature threshold. A still greater problem is that the processing temperature of this material approximately corresponds to the temperature at which this thermally ignitable material will react. For instance, the highest processing temperature in the assembly of the semiconductor module is approx. 270° C. The reaction temperature of this thermally ignitable material must thus be sufficiently greater than this maximum processing temperature in order to avoid a potential false activation, so that the thermally ignitable material may only ignite at a temperature above 300° C. In any case, there are many instances of application in which the semiconductor component already does serious harm at a temperature approximately corresponding to the processing temperature.
[0011] There also exists the need to furnish a power semiconductor module with a thermal protection mechanism that trips in a defined fashion at an arbitrary temperature, preferably a low temperature. The subsequent fate of the power semiconductor module is irrelevant, the only need is to guarantee a reliable interruption.
SUMMARY OF THE INVENTION
[0012] It is accordingly an object of the invention to provide a semiconductor module which overcomes the above-mentioned disadvantages of the prior art apparatus of this general type.
[0013] In particular, it is an object of the invention to reliably interrupt the load circuit of a housed semiconductor component in the case of a malfunction in the load circuit of the semiconductor component, given that the processing temperature is not excessive.
[0014] With the foregoing and other objects in view there is provided, in accordance with the invention, a semiconductor module, including: a housing; terminals for receiving a supply potential; at least one output line for carrying a load current; at least one semiconductor component disposed in the housing, the semiconductor component being conductively connected to the output line; an integrated temperature sensor being housed in the housing, the temperature sensor having a load terminal connected to one of the terminals for receiving the supply potential; and an interruption device housed in the housing. When a first temperature threshold is being exceeded and a first supply potential is being supplied to the terminals for receiving the supply potential, then the temperature sensor conducts a load current causing heating of the temperature sensor. The interruption device is configured for irreversibly interrupting at least the output line when a second temperature threshold is exceeded.
[0015] The inventive semiconductor module thus includes a temperature sensor and an interruption device for irreversibly interrupting the load current in the case of a malfunction. The irreversible break is characterized by two distinct successive steps:
[0016] (1) First, a temperature sensor is provided which detects and monitors the temperature of the semiconductor chip and which is activated at a trip temperature. The term “trip temperature” refers to a critical temperature threshold TS upon whose crossing the protective mechanism engages (i.e. the temperature sensor is activated).
[0017] (2) Secondly, an interruption device is provided which irreversibly interrupts the load circuit of the monitored power MOSFET given that the ignition temperature has been exceeded. The ignition temperature is greater than the trip temperature. The ignition signal by means of which the interruption device is ignited is the temperature of the activated temperature sensor. The term “ignition temperature” refers to the temperature at which the thermally active material of the interruption device ignites. When the thermally active material of the interruption device ignites, its volume rapidly expands. This volume expansion can be expressed in a strongly oxidizing or exploding or heavily frothing character.
[0018] The particular advantage of the invention consists in the linking of two conditions that must exist simultaneously in order to trigger the irreversible interruption which ultimately leads to the destruction of the MOSFET:
[0019] (a) The first condition is the presence of an overtemperature (trip temperature) and the simultaneous presence of an operating voltage. The trip temperature can be set arbitrarily low as a precondition for tripping given the achievement of this temperature. In case this temperature should be attained during the processing of the semiconductor module, for instance during the soldering of the terminals, the other requirement for satisfying the first condition, namely the application of the operating voltage, is not satisfied, and thus the temperature sensor is not activated.
[0020] (b) The second condition is the ignition temperature. The ignition temperature of the actual thermally active and thus destructive material can be any temperature above the trip temperature. This temperature is achieved in that, given the attainment of the trip temperature and the presence of the operating voltage, a mechanism is set in motion which induces this ignition temperature. For instance, this temperature can be generated by the temperature sensor, which has been activated and is therefore heating up intensely.
[0021] The advantage of this arrangement is that the ignition signal is released only if an ignition temperature is exceeded and the operating voltage is simultaneously being applied, i.e. not during the soldering of the unit, because at this time the required operating voltage could not be present, although the ignition temperature may be.
[0022] The following advantages are gained by combining the two conditions:
[0023] I. Because the trip mechanism is separate from the ignition mechanism, this ignition temperature can be selected sufficiently far from the trip temperature. It is therefore possible to avoid, as far as possible, accidental ignition of the interruption device, for instance during the processing of the semiconductor module or upon the triggering of the temperature sensor.
[0024] II. The overall interruption process can also be switched from outside, either directly via the supply voltage or via a separately provided terminal of the power MOSFET. The overall tripping process can thus be sparked either internally or externally.
[0025] III. Lastly, the overall tripping process can be advantageously dimensioned in view of the sensitivity of the temperature sensor, so that the trip temperature can be set to a specific value in a highly precise fashion.
[0026] Typically, the load systems of the semiconductor component and the temperature sensor are arranged in parallel fashion between the terminals for the supply voltage. The temperature sensor is supplied by the supply voltage of the protected MOSFET. But the temperature sensor may also conceivably have a separate supply voltage and thus function independently of the MOSFET.
[0027] Typically, the temperature sensor is not connected to the external connecting leads. Rather, it is connected within the housing to at least one load terminal of the semiconductor component and alternatively to a drive circuit which drives the semiconductor component. In this case, a separate external terminal for the temperature sensor can be forgone.
[0028] What is essential to the functioning of the inventive semiconductor module is that the second temperature threshold is higher than the first temperature threshold. Typically, the first temperature threshold is in the range between 250° C. and 300° C., whereas the second temperature threshold greater than 300° C.
[0029] It is particularly important for the function of the inventive temperature sensor that the temperature sensor, and alternatively the interruption device as well, be arranged in the immediate vicinity of the semiconductor component. This produces a thermal coupling between the temperature sensor and the MOSFET, which guarantees an immediate reaction of the temperature sensor in the case of a malfunction.
[0030] A triac or thyristor is utilized as a temperature sensor, whereby the thyristor or triac advantageously does not have a control terminal.
[0031] If the temperature sensor is constructed as a triac, an additional advantage is gained in that the temperature sensor also trips if the poles are connected the wrong way. If the poles of the power MOSFET are connected the wrong way, a load current which is limited only by the load and the diode flow voltage flows through the inverse diode, which is usually inherent in the power MOSFET. In this case, the power MOSFET no longer functions as a controllable switch. Because of the large voltage drop of the inverse diode, the power MOSFET heats up intensely, and it is no longer possible to cut off the current flow. In the extreme case, absent a separately provided reverse polarity circuit, the power MOSFET can heat up to an extreme degree. In this case, the sensor signal provided by the triac can be utilized as a trigger signal for a trip mechanism of any type which also acts given pole inversion. The switching characteristic of the temperature sensor could also be laid out thermally asymmetrically for a mispole operation and a normal operation; i.e., the current-voltage characteristic curve of the triac can be optimally designed with respect to its first and third quadrants.
[0032] Given the utilization of a thyristor as a temperature sensor, the trip temperature can be purposefully set and thus adapted to the requirements.
[0033] Instead of a thyristor or triac, it is possible to utilize any temperature sensor that causes a rapid and intense current rise when the trip temperature is exceeded. This temperature sensor can also be constructed as a rapidly heating destructive resistance, a bimetal switch, or the like.
[0034] It is particularly important to the function of the inventive semiconductor module that the interruption device is arranged in the immediate vicinity of the bonding wires carrying the load current. In particular, it can be arranged precisely underneath these bonding wires.
[0035] In accordance with an added feature of the invention, a fuse can be alternatively or additionally provided as an interruption device. This fuse is connected in series with the load system of the semiconductor component and the temperature sensor.
[0036] In accordance with an additional feature of the invention, besides its primary function as a temperature sensor, the thyristor (or triac) simultaneously functions as an interruption device. Here, the intense heating of the thyristor or triac leads directly to the bursting of the housing, and thus the destruction of the semiconductor module.
[0037] In accordance with another feature of the invention, the interruption device contains an ignitable, volume-expansive material. The volume-expansive material exhibits a foaming and/or strongly oxidizing and/or explosive characteristic when the second temperature threshold is exceeded.
[0038] In accordance with a further feature of the invention, the semiconductor component is a controllable power semiconductor component, in particular a power MOSFET. But it would also be possible to utilize any other semiconductor switch, for instance an IGBT, a JFET, a bipolar transistor, and so on.
[0039] In accordance with a concomitant feature of the invention, the semiconductor component and the temperature sensor are integrated monolithically in a single chip. This is particularly advantageous from a production standpoint. The advantage of a chip on chip assembly is that the sensor is usually not destroyed when the MOSFET is destroyed.
[0040] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0041] Although the invention is illustrated and described herein as embodied in a semiconductor module, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0042] The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] [0043]FIG. 1 is a circuit diagram of a general embodiment of the inventive semiconductor module;
[0044] [0044]FIG. 2 is a circuit diagram of development of the general embodiment of the semiconductor module;
[0045] [0045]FIG. 3 a shows a temperature sensor formed as a triac;
[0046] [0046]FIG. 3 b shows a temperature sensor formed as a thyristor;
[0047] [0047]FIG. 4 is the current-voltage characteristic curve of a temperature sensor that is constructed as a triac, at low temperature and at high temperature;
[0048] [0048]FIG. 5 is a sectional representation of a first exemplary embodiment of the inventive semiconductor module;
[0049] [0049]FIG. 6 is a sectional representation of a second exemplary embodiment of the inventive semiconductor module;
[0050] [0050]FIG. 7 is a circuit diagram illustrating a first application of the inventive semiconductor module;
[0051] [0051]FIG. 8 is a circuit diagram illustrating a second application of the inventive semiconductor module;
[0052] [0052]FIG. 9 is a circuit diagram illustrating a third application of the inventive semiconductor module; and
[0053] [0053]FIG. 10 is a circuit diagram illustrating a fourth application of the inventive semiconductor module.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] Unless otherwise indicated, identical or functionally identical elements and signals are provided with the same reference characters in the Figures.
[0055] Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown an inventive semiconductor module that includes a power MOSFET 2 and a temperature sensor 3 . The drain-source load system of the power MOSFET 2 is connected between two terminals 4 , 5 at which a supply voltage is present. The gate terminal G of the MOSFET 2 is connected to a control terminal 6 . The temperature sensor 3 is arranged between two additional terminals 7 , 8 at which a second supply voltage can be applied. The temperature sensor 3 is arranged in the immediate vicinity of, and is in thermal contact with, the MOSFET 2 , so that it can detect the temperature of the MOSFET 2 .
[0056] In contrast to the general circuit diagram of a semiconductor module 1 shown in FIG. 1, in which the supply voltages of the MOSFET 2 and the temperature sensor 3 are different, FIG. 2 shows an embodiment of the semiconductor module 1 in which the temperature sensor 3 and the MOSFET 2 are supplied with the same supply voltage. In the example shown in FIG. 2, a positive supply potential VDD is present at the first terminal 4 , whereas the potential of the reference ground GND is present at the second terminal 5 . A gate control potential VG can be coupled in via the control terminal 6 .
[0057] The temperature sensor 3 can be advantageously integrated into the power MOSFET 2 , so that it detects and signals an impending thermal destruction of the power MOSFET 2 , and thus of the semiconductor module, directly where it is to occur, namely on the semiconductor chip. The temperature sensor 3 must be supplied with a voltage in order to function properly. In the ideal case, a drive is not necessary for the temperature sensor 3 . A triac, shown in FIG. 3 a , or a thyristor, shown in FIG. 3 b , is advantageously suitable as the temperature sensor 3 . Unlike known triacs and thyristors, the components shown in FIGS. 3 a and 3 b have no gate control.
[0058] [0058]FIG. 4 shows the current-voltage characteristic curve for a temperature sensor 3 that is constructed as a triac or a thyristor.
[0059] The characteristic curve in FIG. 4 is characterized by a first region (curve A) with a small slope and a second region (curve B) with a very steep slope. Because the thyristor (or triac) cannot be activated for lack of a gate drive, its characteristic curve exhibits the curve (A) in normal operation. Thus, in normal operation (i.e. at temperatures which are less than the temperature threshold of the thyristor or triac (T<Ts)), the thyristor (triac) is blocked, and only a minimal blocking current flows, if any.
[0060] But the thyristor or triac automatically switches on at a defined, relatively high temperature threshold (T>TS). Therefore, the semiconductor components that are utilized for the temperature sensors 3 , which are thyristors or triacs, have a very high temperature threshold, for instance in the range between 250 and 300° C. These high temperature thresholds are typically substantially undershot in the normal operation of the power MOSFET 2 and are attained only given a destroyed out-of-control power MOSFET 2 , so that the thyristor or triac ignites only in the event of a malfunction, i.e. when the temperature threshold (T>TS) is exceeded. The current-voltage characteristic curve then exhibits a very large slope (curve B). The sensor signal that is generated by the igniting of the thyristor or triac can no longer be used for protecting the power MOSFET 2 , because this is typically already destroyed; however, it is utilized as a sensor signal for protecting the semiconductor module 1 or its environment.
[0061] [0061]FIGS. 5 and 6 show two sections of an inventive semiconductor module, in order to illustrate the operation of the inventive temperature sensor with the interruption device.
[0062] The semiconductor module 1 shown in FIGS. 5 and 6 includes a housing 11 . The housing 11 surrounds a semiconductor chip 12 , which is fastened onto a lead frame 13 . The semiconductor chip 12 can contain one or more power MOSFETs 2 . On the surface of the semiconductor chip 12 is a temperature sensor 14 , which is integrated in an additional semiconductor body. The temperature sensor 14 can be constructed as a triac 9 or a thyristor 10 as shown in FIGS. 3 a and 3 b.
[0063] In the present exemplary embodiments, the temperature sensor 14 is installed directly on the semiconductor chip 12 . But this is not necessarily required. It is sufficient for the temperature sensor 14 to be thermally connected to the semiconductor chip 12 , and the temperature sensor 14 is therefore situated in its immediate vicinity. Though this is not represented, another conceivable technique would be to place a thermally conductive layer between the temperature sensor 14 and the semiconductor chip 12 for the purpose of guaranteeing good thermal coupling between the semiconductor chip 12 and the temperature sensor 14 .
[0064] In FIGS. 5 and 6, the temperature sensor 14 and the MOSFET are integrated in separate semiconductor bodies, respectively. But the temperature sensor 14 may also conceivably be integrated in the semiconductor chip 12 . The temperature sensor 14 should ideally be constructed and installed independently of the semiconductor chip 12 and thus independently of the power MOSFET 2 integrated within it, so that the sensor is able to continue to work perfectly for a limited time given a damaged or destroyed power MOSFET 2 . In this case, the chip-on-chip technology according to the exemplary embodiments shown in FIGS. 5 and 6 would be the obvious solution, in which the temperature sensor 14 is integrated in a separate semiconductor body and is therefore is able to work independently of a possible malfunction of the semiconductor chip 12 or the power MOSFET 2 within it. However, a fairly independent, monolithic integrating of the temperature sensor 14 into the semiconductor chip 12 is also possible.
[0065] The semiconductor module 1 further includes one or more terminal pins 15 , which protrude from the housing 11 and which are in conductive contact with the semiconductor chip 12 via corresponding bonding wires 16 . Additional bonding wires 17 are also provided, via which the temperatures sensor 14 is conductively contacted to the terminal pins 15 . The semiconductor chip 12 and the temperature sensor 14 can be respectively connected to the terminals 4 , 5 for the supply voltage VDD, GND and to a control potential VG by the terminal pins 15 .
[0066] Next, the function of the temperature sensor 14 will be described with respect to the irreversible blowing behavior that takes place in the semiconductor module 1 in the event of an impermissibly high temperature.
[0067] In normal operation, and thus at temperatures below a critical temperature threshold T<TS, the temperature sensor 14 is blocked, and no load current I flows across the temperature sensor.
[0068] In the abnormal condition (T>TS), for instance given a short of one or more power MOSFETs 2 , the temperature on the semiconductor chip 12 rises abruptly or slowly and uncontrollably until the critical temperature TS is exceeded. When the critical temperature TS is exceeded, the temperature sensor 14 , which is thermally coupled with the semiconductor chip 12 , abruptly becomes conductive and begins the conduct a current I via its load system. Because this current I is initially unlimited, a shorting of the supply voltage occurs. The temperature sensor 14 is thereby heated intensely within a short time. In the exemplary embodiment shown in FIG. 5, this leads to bursting of the housing 5 , and thus the bonding wires 16 of the semiconductor chip 12 that carry the current are ripped. To accomplish this, the temperature sensor 14 is ideally situated in the immediate vicinity of the bonding wires 16 , for instance directly below them.
[0069] Nevertheless, in the unfavorable case, the actual power MOSFET 2 on the semiconductor chip 12 is likewise damaged by the fusing of temperature sensor 14 . The self-destruction of the power MOSFET 2 , and therefore the current interruption is initiated within a very short time. But this is willingly accepted into the bargain. Rather, what is important here is that the self-destruction of the defective power MOSFET 2 and the current interruption occur as rapidly as possible, so that a further destructive environment will not be fostered. Thus much greater damage is prevented.
[0070] In the exemplary embodiment shown in FIG. 6, an interruption device 18 is additionally installed on the temperature sensor 14 . In the event of a failure, the temperature sensor 14 is shorted and heats up in a very short time. The interruption device 18 has an ignition temperature. If the ignition temperature of the interruption device 18 is exceeded, it is ignited, and the volume-expansive characteristic of the interruption device 18 leads to bursting of the housing 11 and specifically to splitting or tearing of the bonding wires 16 carrying the current. The shorted load circuit of the defective power MOSFET 2 is thus interrupted in a defined and irreversible fashion.
[0071] Two different principles of the inventive arrangement are shown in FIGS. 5 and 6. In the example of FIG. 5, the temperature sensor 14 and the interruption device are realized by the temperature sensor 14 itself, whereas in the example shown in FIG. 6, the function of the volume-expansive material is realized by a separately provided interruption device 18 .
[0072] FIGS. 7 to 10 show circuit diagrams of advantageous applications of the inventive semiconductor module.
[0073] [0073]FIG. 7 shows a power MOSFET 2 as a high-side switch. A load 20 15 is arranged between the source terminal S and the terminal 5 connected to the reference potential GND. The temperature sensor 3 is interposed between the drain terminal D of the power MOSFET 2 and the terminal 5 . An external fuse 21 , for instance a destructive resistor is also interposed into the load system of the power MOSFET 2 . The fuse 21 is connected to the drain D of the power MOSFET 2 . The fuse 21 serves here as an interruption device, which brings about an interruption of the current of the power MOSFET 2 given the triggering of the temperature sensor 3 . Alternatively or additionally, the current interruption could also be accomplished via the temperature sensor 3 .
[0074] [0074]FIG. 8 is a circuit diagram showing the power MOSFET 2 being constructed as a high-side switch as shown in FIG. 7 and also being constructed as a smart power switch. To this end, a drive circuit 22 is disposed between the control terminal 6 and the gate terminal G of the power MOSFET 2 . The drive circuit 22 drives the power MOSFET 2 with a gate control potential VG. The drive circuit 22 is advantageously also disposed between the terminals 4 , 5 of the supply voltage source.
[0075] In contrast to the exemplary embodiment shown in FIG. 8, the temperature sensor 3 in the exemplary embodiment shown in FIG. 9 is interposed between the drain terminal D and the control terminal 6 . In the failure condition, the temperature sensor 3 provides the positive supply potential VDD to the input 6 as an error signal for further processing. Advantageously, a control device 23 —for instance a microcontroller, microprocessor or logic circuit—is provided, which is coupled with the input 6 of the semiconductor 1 via an input resistor 24 . The signal of the temperature sensor 3 can be input into the control device 23 by way of a feedback branch 25 . If the trip temperature is not exceeded, the temperature sensor 3 blocks. The input of the semiconductor module 1 is then driven with the usual logic levels for the gate control potential VG, for instance 0 volts and 5 volts.
[0076] The advantage of the arrangement shown in FIG. 9 is that an additional, external terminal is not required for the temperature sensor 3 , and thus the temperature sensor 3 can advantageously be in an integrated form.
[0077] In the exemplary embodiments shown in FIGS. 7 to 9 , the operating voltage which is required for the functioning of the temperature sensor 3 is drawn directly from the drain potential of the power MOSFET 2 . The risk of the power MOSFET also shorting only arises when this drain potential is also contained in the power MOSFET, and thus the above mentioned first condition is satisfied.
[0078] [0078]FIG. 10 shows the circuit diagram of a power MOSFET 2 that is constructed as a low-side switch, in which the load 20 is arranged between the drain terminal D and the terminal 4 connected to the positive supply potential VDD. The temperature sensor 3 is arranged between the input 6 and the terminal 4 connected to the positive supply potential VDD. But of course this could also be arranged between the terminals 4 , 5 .
[0079] In sum, it can be stated that the temperature sensor and the interruption device constructed as specified above represent a total departure from the prior art, in that an irreversible fuse mechanism for power semiconductor components can be provided, which links the interruption to two different conditions: the presence of a supply voltage and the presence of an overtemperature.
[0080] The present invention has been described to best explain the principle of the invention and its practical applications, however, the invention can also be realized in various other embodiments given suitable modifications.
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A semiconductor module includes a housing with at least one semiconductor component that is conductively connected to at least one output line. An integrated temperature sensor is also housed in the housing. This sensor is connected, via at least one of its load terminals, to a terminal for receiving a supply potential. The temperature sensor conducts a load current that heats-up the temperature sensor when a first temperature threshold is crossed and a supply potential is in being supplied. A housed interruption device is arranged in such a way that it interrupts the output lines carrying the load current when a second temperature threshold has been exceeded.
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This is a continuation of U.S. patent application Ser. No. 07/407,635, filed Sep. 15, 1989, now abandoned, which is a continuation of U.S. patent application Ser. No. 07/213,899, filed Jun. 30, 1988, now U.S. Pat. No. 4,877,168, which is a continuation of Ser. No. 07/003,134, filed Jan. 14, 1987, now U.S. Pat. No. 4,754,905, which is a continuation of Ser. No. 06/778,385, filed Sep. 20, 1985, now U.S. Pat. No. 4,684,048.
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to vehicle article or luggage carriers and more particularly to a new and improved vehicle luggage carrier of the type shown in applicant's U.S. Pat. No. 4,099,658, issued Jul. 11, 1978. Generally, the article carrier of the present invention is of the type which comprises two or more slat-type elements which are fixedly secured to an exterior horizontal surface of an automotive vehicle, such as a vehicle roof or a trunk lid, and which are permanently attached to that surface and adapted to have ancillary article constraining members removably and/or adjustably secured thereto and includes a system of adjustable and fixed components which cooperate with one another and which may be removable in some instances.
The present invention has as one principal object to provide a luggage rack with slidably adjustable and fixedly engageable components including slidably adjustable cross members having tie downs for boxes, luggage, and the like associated with the cross members. The cross members and tie downs of the present invention are not only adjustable but also may be either removable from the luggage carrier or stored within other components of the luggage carrier substantially out of view. Each cross member may include at least one tie down and/or abutment member for optimum securement of articles or luggage to the article carrier and thereby the vehicle.
A significant advantage of the article carrier of the present invention is that the article carrier has a low profile when not in use with minimal structure projecting above the plane of the vehicle surface to which the article carrier is attached, thereby minimizing any adverse wind noise or fuel economy effects that would exist with any portion of the carrier being substantially vertically elevated.
The present invention further incorporates all of the aesthetically appealing features and the myriad of functional features and optional accessories disclosed in the slat-type luggage carriers of applicant's prior patents, such as that described in U.S. Pat. No. 4,099,658, referenced above.
Even more notably, the present invention elevates the aerodynamic design of a vehicle article carrier system having adjustable and/or removable components to an improved design not previously attained by any prior art carriers. The elongated support member or slat of the present invention providing the foundation of the carrier has surfaces which not only flow into and integrate with the surface of the vehicle, but also includes a channel along which components may be adjusted and/or removably attached.
In cooperation with this improved support member or slat, a new and improved locking mechanism for attaching the adjustable and/or removable components of the system to the member or slat is included having an aerodynamic, hidden release element.
Additional advantages are provided in the combination of the above features with other fixed components of an article carrier system and an improved cross member construction integrating adjustable tie down and/or abutment elements disposeable out of view, similar to those described in applicant's U.S. Pat. No. 4,460,116, issued Jul. 17, 1984, and further integrating a pad construction in a cross rail spaced from a functional channel on load bearing cross members for a more stable yet cushioned load bearing support for articles disposed on the cross members.
Other objects and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of an automobile showing an article carrier mounted thereon which is constructed in accordance with the principles of the present invention;
FIG. 2 is an enlarged sectional view of the support member portion of the structure illustrated in FIG. 1 taken along the line 2--2 thereof;
FIG. 3 is an enlarged sectional view of the support member portion of the structure illustrated in FIG. 1 taken along the line 3--3 thereof;
FIG. 4 is an enlarged sectional view of one of the front stanchion portions of the structure of FIG. 1 taken along the line 4--4 thereof;
FIG. 5 is an elevated enlarged fragmentary view of one of the front stanchion assemblies of FIG. 1 taken in the direction of arrow 5.
FIG. 6 is a cross-sectional view of the cross rail portion of FIG. 5 taken along the line 6--6 of FIG. 5;
FIG. 7 is an elevated enlarged fragmentary view of one of the rear stanchion portions of the structure of FIG. 1 taken in the direction of arrow 7;
FIG. 8 is a cross-sectional view of the cross rail portion of FIG. 7 taken along the line 8--8 of FIG. 7;
FIG. 9 is a cross-sectional view of the rear stanchion of FIG. 7 locked to the base support member or slat of FIG. 1;
FIG. 10 is a cross-sectional view similar to FIG. 9 of the rear stanchion of FIG. 7 released from the base support member or slat of FIG. 1;
FIG. 11 is a view similar to FIG. 4 of the rear stanchion of FIG. 9 looking in the direction of arrow A in FIG. 9 having portions broken away;
FIG. 12 is a view similar to FIG. 11 of the rear stanchion of FIG. 10 looking in the direction of arrow B in FIG. 10 having portions broken away;
FIG. 13 is a vertical sectional view of either FIG. 6 or FIG. 8 along the line 13--13 of either view of the tie down disposed in the cross rail of either view; and
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now in detail to FIG. 1 of the drawings, a vehicle luggage carrier 20 is shown in operative association with a generally horizontally disposed roof 22 of a typical automotive vehicle 24. Generally speaking, the luggage carrier 20 comprises a pair of laterally spaced, longitudinally extending support members or slats 26 and 28 which are secured upon the roof 22 at positions adjacent the lateral sides or edges thereof. In the embodiment illustrated, the members 26 and 28 are disposed over the seam where the roof 22 meets the remainder of the body portion of the vehicle, where the roof 22 has a downward curvature, which places the members 26 and 28 adjacent the horizontally extending surface portion of the roof 22. The members 26 and 28 have an external surface configuration that flows aerodynamically and smoothly in the surface of the vehicle 24.
Intermediate portions of the member 26 (or 28) are illustrated in cross-section in FIGS. 2 and 3. The member 26 comprises first 30 and second 32 exterior surfaces having an elongated channel 34 between the surfaces. The channel 34 comprises an elongated recess 36 and a liner 38 disposed in said recess 36 by means of, with reference to FIG. 3, fasteners 35 set through bores 37 in the liner and bores 39 in the recess 36. The liner 38 has upper article supporting surfaces 40, 42 disposed on a pair of inwardly directed upper flanges 44, 46, a pair of sidewalls 48, 50 extending downwardly therefrom, and a base 51 extending between the walls 48, 50 and integrated with the walls 48 and 50 via walls 52 and 53, respectively. The upper flanges 44, 46 are rolled back as illustrated in FIGS. 2 and 3 to provide grooves 45 and 47 in the interior of the channel 34 for the purposes as will be described below. The fasteners 35 are set below the surface of the base 51 by placement in recesses 55, as shown in FIGS. 3 and 4.
Referring to FIG. 2, a pad 54 is disposed between each of the members 26 and 28 and the roof 22. Each member 26 or 28 is secured to the roof 22 by a plurality of threaded collar studs 56 threadably engaged to the member 26 or 28 within a bore 58 and engaged with the roof 22 at the interior of the roof 22 through a plurality of holes 60 in the roof by means of a plurality of nuts 62. The studs 56 engage the members 26 and 28 at the plurality of bores 58 by augering into the members 26 and 28, which are plastic in the preferred embodiment, or by other conventional means. In this manner, the studs 56 are all hidden from view when the members 26 and 28 are assembled on the vehicle.
The article carrier 20 of FIG. 1 further comprises a pair of transversely or laterally extending cross member assemblies 70 and 72 and may also include a tie down 73 and a plurality of intermediate supporting slats 75. The front cross member assembly 70 comprises a pair of stanchions 74 and 76 telescopically engaged with and secured to a front cross rail 78. Referring to FIG. 4, the stanchion 74 (and likewise 76) is fixedly secured to the support member 26 (and 28) via two posts 80 and 82 which fit into two bores 84 and 86 at the front portion of each of the members 26 and 28 and via two bolts 88 and 90 fitting through recesses 92 and 94 and apertures 96 and 98 in each of the stanchions 74 and 76 into corresponding threaded bores 100 and 102 in the members 26 and 28.
The stanchions 74 and 76 have an aerodynamically streamlined curvature as illustrated in FIGS. 1, 4, and 5 and telescopically engage the front cross rail 78 in a similarly aerodynamically streamlined manner. Referring to FIGS. 4 and 6, the cross rail 78 comprises a bottom surface 104 from which a curved leading surface 106 and a curved trailing surface 108 extend upwardly. The upper surface 110 of the cross rail 78 comprises a series of elongated article supporting surfaces including surfaces 111 and 112 disposed one on each side of an elongated first channel 114 and a surface 116 disposed on an elongated front bumper 118 set into a second channel 120 in the rail 78. The bumper 118 has a pair of elongated flanges 122 and 124 on the underside thereof to secure the bumper in the second channel 120.
Referring to FIGS. 4 and 6, the first channel 114 has an interior cross-section having a base 126, a pair of sidewalls 128 and 130, and a pair of interior clamping surfaces 132 and 134. Within the first channel 114 (FIG. 6) is disposed a tie down/positioning member 136 similar to that disclosed in applicant's U.S. Pat. No. 4,460,116, issued Jul. 17, 1984. The tie down/positioning member 136 (FIGS. 6 and 13) is comprised of an upper section 140 having a vertically disposeable abutment surface 142 and an aperture 144 therein, a base portion 146 including spring biasing members 148, and a pivot 150 for pivotably associating the upper section 140 with the base portion 146. The upper section 140 also includes a lower cam member 151 on the opposite side of the pivot 150 which engages the base 126 of the first channel 114 with pivotal movement of the upper section 140 from the horizontal to the vertical and clamps the biasing members 148 against the clamping surfaces 132 and 134 and lock the tie down/positioning member 136 in any selected position along the length of the first channel 114. The ends of the channel 114 also include an abutment 152 (FIG. 5) to aid in disposing the upper section 140 from the horizontal to the vertical.
The rear cross member assembly 72 is adjustable to any selected position along the length of the members 26 and 28, as determined by a stop 154 (FIGS. 4 and 5) or by the end of the channel 34, and may also be removed, if desired. The assembly 72 (FIGS. 1 and 7) comprises a pair of stanchions 160 and 162 telescopically engaged with and secured to a rear cross rail 164. The stanchions 160 and 162 each engage a corresponding support member 26 or 28 at the channel 34 thereof via a locking mechanism 166 (FIGS. 9 through 12). The locking mechanism 166 comprises a pivoted lever 168 mounted to each stanchion 160 or 162 within a recess 170 and secured to a pin 172. The lever 168 is limited in movement by a stop 169 (FIG. 11) to indicate a vertically disposed position for the lever 168. The pin 172 threadably engages the lever 168 in a bore 175 and communicates with the interior 174 of the stanchion and engages an eccentric member 178 disposed in the stanchion interior 174 via a bore 176 at a position offset from the center of the member 178 to eccentrically move a pin 180 mounted on the member 178 at bore 181. Referring to FIGS. 11 and 12, the pin 180 moves within a yoke 182 which is integrated with a hook 184. Guides 186 and 188 may be disposed one on each side of the yoke 182 to stabilize the linear vertical movement of the hook 184. The hook 184 is formed with a curvature to permit some resiliency. Further tension is applied to the hook 184 by a tensioning member 186 fixedly disposed adjacent the path of movement of the hook 184 as illustrated in FIGS. 9 and 10.
In operation, the stanchion 160 or 162 is placed over the channel 34 of the support member or slat 26 and the hook 184 is placed within the channel 34. The stanchion 160 or 162 also includes front and rear alignment posts 188 and 190 (FIG. 7) which are also placed within the channel 34 as the stanchion is set upon the upper surfaces 40 and 42 of the member 26 or 28. Once alignment is attained, the lever 168 is rotated from a horizontally disposed position (FIG. 10) to a vertically disposed position (FIG. 9) abutting against the stop 169 and lifting the hook 184 so that its leading edge 192 is engaged with the groove 47 of the channel 34 to clamp the stanchion 160 or 162 to the support member or slat 26. The return of the lever 168 to a horizontal disposition releases the hook 184 and the stanchion 160 or 162 from the member or slat 26 for adjustment or removal.
Referring to FIGS. 7 and 8, the rear cross rail 164 is similar to the front cross rail 78 in that it has a bottom surface 194 from which a curved leading surface 196 and a curved trailing surface 198 extend upwardly. It should be noted that the leading surface 196 and trailing surface 198 may be reversed, however, depending upon the selected placement of the rear cross rail assembly 72 on the members 26 and 28. The upper surface 200 of the cross rail 164 comprises a series of elongated article supporting surfaces including surfaces 202 and 204 disposed one on each side of an elongated first channel 206, a surface 208 disposed on an elongated front bumper 210 set into a second channel 212 in the rail 78 and an additional surface 213. The bumper 210 has a pair of elongated flanges 214 and 216 on the underside thereof to secure the bumper in the second channel 212.
Referring to FIG. 8, the first channel 212 has an interior cross-section having a base 226, a pair of sidewalls 228 and 230, and a pair of clamping surfaces 232 and 234. Within the first channel 212 is disposed a tie down/positioning member 136 again similar to that disclosed in applicant's U.S. Pat. No. 4,460,116, issued Jul. 17, 1984. The tie down/positioning member 136 is again comprised of an upper section 140 having a vertically disposeable abutment surface 142 and an aperture 144 therein, a base portion 146 including spring biasing members 148, and a pivot 150 for pivotably associating the upper section 140 with the base portion 146. The upper section 140 also includes a lower cam member on the opposite side of the pivot 150 which engages the base 226 of the first channel 212 with pivotal movement of the upper section 140 from the horizontal to the vertical and clamp the biasing members 148 against the clamping surfaces 232 and 234 and lock the tie down/positioning member 136 in any selected position along the length of the first channel 212. The ends of the channel 212 also include an abutment 252 (FIG. 7) to aid in disposing the upper section 140 from the horizontal to the vertical.
While it will be apparent that the preferred embodiment of the invention disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.
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An article carrying system for operative association with an automotive vehicle having an exterior generally horizontal surface, such as a trunk lid or roof, the system comprising a pair of elongated support members or slats which have a configuration which flows conformably and aerodynamically into the surface of the vehicle and which are permanently secured to the vehicle. The support members have longitudinally extending channels for supporting adjustable and/or removable components of the system, including tie downs and cross members which components are also provided with aerodynamic designs compatible with the remainder of the system. Provision is also made for association of components of the system, such as cross members, to be fixedly located on the support members. An aerodynamic locking mechanism is also disclosed for use in selected adjustable and/or removable components of the system which includes a hidden actuation mechanism and a hooking action to lock the component to the support member or slat.
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CROSS-REFERENCES TO RELATED APPLICATIONS
Text
FIELD OF THE INVENTION
The present invention relates generally to socks and particularly to low profile active wear socks that can be worn for various exercises and disciplines and particularly pilates, yoga, karate, gymnastics and other floor sports.
BACKGROUND OF THE INVENTION
Description of the Prior Art
Various slippers and footwear have been proposed for use in active routines involving quick precise movement on a floor surface. Early work led to the proposal of stockings formed with tubes for receipt of a wearer's toes so that the toes could be articulated in use. A stocking of this type is shown in U.S. Pat. No. 1,308,483 to Craighead.
Other efforts have led to the proposal of socks of various configurations to address issues of perspiration. One such dry sock system is shown in U.S. Pat. No. 6,016,575 to Prychak. This sock is constructed with an upper portion fabricated from an elastomeric material and a lower portion constructed from an absorbent material and including toe sections. Socks of this type are satisfactory for their intended purpose but suffer the shortcoming that participants involved in active floor sports wearing such socks would not typically enjoy feeling of firm and reliable gripping with the underlying floor.
Various footwear has been proposed to enhance the performance of, for instance, track and field participants. In this regard, it has been proposed to construct a form fitting foot and toe cover from a stretchable fabric and to apply a rubber like material by a spatula to the entire bottom of the covering or to specific selected areas to act as spikes as by a hot melt glue. A device of this type is shown in U.S. Pat. No. 4,651,354 to Petrey. Petrey purposes that the rubberized material be built up to form a spike shape for better grip of the track or playing field. While satisfactory for track or field sports, such coverings have the shortcoming that the rubberized pads or spikes do not typically provide for firm gripping with a floor surface and, for instance, pilates. Furthermore, full sole coverings or spike-like patches do not lend to use or comfortable low profile relatively thin woven sock material and would likely be subject to cracking as the material was flexed in use.
The need for anti-skid gloves and footwear in high disciplined yoga exercises has long been recognized. In this regard, it has been proposed to provide footwear constructed of leather and covered in certain areas by a rubber material. Device of this type are shown in U.S. Pat. No. 6,766,536 to Aarons. While providing some support against slippage, devices of this type suffer the shortcoming that the footwear does not provide for a high degree of flexing and identical toe tubes and fails to afford the tactility simulating the feel of bare foot exercises.
Other efforts to provide gloves and socks for yoga activity has led to a proposal that a sock be formed with a separate big toe tube, the remaining toes being housed together at the end of the sock and a low coefficient of friction material be added. A device of this type is shown in Publication No. 2005/0091729 published May 5, 2005 to Alley. Such socks suffer a number of shortcomings including the fact that for pilate applications it is important that the five toes of the foot be allowed to spread apart during the athletic maneuvers involved and that all five toes have a high coefficient grip with the underlying floor surface.
Other athletic socks have been proposed which include separate toe compartments and are designed particularly for athletic activity. Such a sock is shown in U.S. Pat. No. 6,708,348 to Romay. Socks of this type suffer the shortcoming that, in addition to being relatively expensive to manufacture, they have a relatively slippery sole surface which discourages use in direct contact with floor exercises.
SUMMARY OF THE INVENTION
The gripping sock of the present invention is characterized by a woven low profile sock configured with a sole area having small dots in the form of high friction buttons arrayed about the bottom thereof to, in practice, maintain frictional contact with the underlying support surface during the active maneuvers in a floor exercises.
There has been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described herein and which will form the subject matter of the claims appended hereto.
In this respect, before explaining my preferred of the invention in detail, it is to be understood is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purposes of descriptions and should not be regarded as limiting.
As such, those skilled in the art will appreciate the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions in so far as they do not depart from the spirit of the present invention.
The sock will be form fitting and actually present a feeling not unlike a second skin. The toes are separated in practice to enhance the balance, flexibility, performance and minimize perspiration. In those embodiments where the sock is constructed of cotton, a natural fiber that breathes that, it serves to reduce moisture and friction between the toes, provides precise control and can eliminate blistering during workouts.
Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, the features of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a bottom plan view of a gripping sock embodied in the present invention;
FIG. 2 is a left hand side view thereof;
FIG. 3 is a top plan view thereof;
FIG. 4 is a partial vertical sectional view, in a large scale, taken along the line 4 - 4 of FIG. 1 ;
FIG. 5 is a right side view, in reduced scale, of the high friction sock of FIG. 1 on a wearer's foot;
FIG. 6 is a partial top plan view taken along the line 6 - 6 of FIG. 5 ; and
FIG. 7 is a detail view, in a large scale, taken from the circle 7 in FIG. 5 .
FIG. 8 is a bottom view of an embodiment of the gripping sock with at least 500 high friction buttons.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 , 4 and 7 , the gripping sock of the present invention includes, generally, a knit tube 21 in the shape of a sock, an ankle portion 23 foot portion 25 and sole 27 . The sole includes heel and ball and sections 31 and 33 toe sections formed by the bottom walls of respective tubes 34 , 35 , 36 , 37 , 38 and 39 adhered to the underside of the sole portion is an array of high friction small diameter buttons 37 spaced throughout and located under at least the heel ball and toe portions of the sock.
Socks and particularly golf socks and the like are available in a relatively thin gauged material and are typically woven such that the sock material will stretch to fit over feet of various different sizes and shapes. In my invention, I prefer a relatively thin gauged weave, seamless weave, preferably about 30 gauge, to enhance the tactile characteristics thereof in use. The heddle may be about 130 (60×2) and the thread 30 S single cotton. 30 S single cotton is a specific example of a more general class of materials comprised of natural fibers. A sock is typically formed with a band around the ankle area and with a cup shape in the area of the heel section 31 . In a typical sock for adult use, the sock, in its unstretched condition, may have a sole width of about 3½″ inches and be about 6″ inches long. I prefer to have a fairly dense concentration of high friction buttons 37 disposed about the entire sole area and particularly in the heel ball and toe section. I have found that by applying a generally uniform concentration of small diameter buttons about the sole area I can be assured that the working foot area of the athlete in contact with the underlying floor surface will always have several buttons in contact with the floor surface to maintain a high friction resistance to unwanted slippage. In my preferred embodiment, I array the buttons in a diagonal, spaced apart rows underneath the sole and arranged in checker board fashion so as to also form approximately 27 to 29 longitudinal columns spaced laterally apart and about 33 lateral rows spaced longitudinally apart. I array about 13 to 15 buttons in the section underneath the big toe and about 8 to 9 under the second toe, 7 to 9 under the third toe, about 7 on the fourth toe and about 5 under the little toe.
Underneath the ball, arch and heel I prefer at least 500 buttons (see FIG. 8 ), 900 preferably and for high energy activities about 950 buttons so that the small diameter buttons will add only minimum bulk to the body of the sock and present little resistance to foot articulation, while assuring that a plurality of buttons are always in contact with the underlying surface to thus maintain a firm grip to prevent accidental slippage.
In my preferred embodiment, I provide buttons which actually are more like dots and having a horizontal cross section of about ⅛″ of an inch, a height of about 1/16″ of an inch and a pattern spacing buttons uniformly apart ⅜″ of an inch center to center. The button are preferably manufactured of rubberized material having substantial flexibility and are either flat on the bottom or formed with upwardly concave dimples to act as mini-suction cups when pressed against smooth polished floor. The sock body may be woven in a conventional manner and the button adhered thereto by a high temperature and moisture resistant adhesive.
With this construction I have discovered that the participant can easily slide the gripping sock onto his or her foot and to present a feel not unlike that of a bare foot thus affording maximum flexibility, maneuverability and gripping action. The placement of the wearer's toes within the toe tubes 34 , 35 , 36 , 38 and 39 positions the toes for ready splaying during various floor maneuvers such that the toes can be bent in the metatarsal area as shown in FIG. 5 to spread out as shown in FIG. 6 to thus provide a high degree of maneuverability and flexibility giving the athlete a sense of freedom and security as is so important for pilates. As the exercise is undertaken and forces applied through the foot to the underlying floor, the composite array of buttons in, for instance, the ball and toe area will provide total support for the wearer's weight and will resist slippage as shown in FIG. 7 thereby maintaining a firm grip on the floor surface and resisting unwanted sliding during the floor maneuver.
My invention has proven particularly popular amongst pilates enthusiasts. In this regard, the socks are relatively compact to pack in the wearer's tote kit and, when the exercises are to be commenced, the wearer's street shoes may be removed and the thin woven sock will readily stretch approximately 10% to slide over the wearer's foot and up over the ankle with the toes being received in the toe tubes 34 , 35 , 36 , 38 & 39 as shown in FIGS. 5 and 6 . Then, as the wearer manipulates through various maneuvers, whether with the weight primary on the heel, on the ball, foot or up on the toes a firm reliable grip will be maintained with the floor surface. That is, the multiple friction buttons under the ball of the foot and toe as the wearer rises up on the ball of the foot and toes as shown in FIG. 5 , the toes are free to splay apart and, on the order of 44 to 45 buttons under the toes and an additional 4 to 5 rows of buttons under the ball of the foot will be in contact with the floor to thus create a substantial cumulative area of frictional contact to provide a stable and reliable support platform under the foot to thereby generate confidence in the mind of the wearer. The buttons, being dimpled upwardly in the center of the bottom surfaces, tend to assume an individual large area foot prints to afford a high degree of frictional contact and acting somewhat as small suction cups.
As the wearer moves about the floor and assumes different positions thus maneuvering the foot about from front to back and side to side, her or she can expect a high number of buttons to maintain favorable contact with the floor surface to thus afford a grip which will minimize slippage irrespective of the particular degree to which the foot is articulated medially, laterally, forward or back.
From the foregoing, it will be apparent that the high grip foot sock of the present invention provides an economical and highly reliable sock which is comfortable to wear, reliable and which will enhance the tactical feel one desires to achieve in high skill active floor exercises.
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A woven sock body having a multitude of high friction dots defining friction buttons arrayed around the bottom thereof.
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BACKGROUND OF THE INVENTION
This invention relates generally to commercial liquid containers and particularly to those molded of plastic material which are intended to be disposable and used for commercial distribution of liquids such as engine lubricating oil and the like.
Many liquid products such as cleansers, solvents and lubricating oils share a common method of manufacture, distribution and sale in that they are typically produced in bulk quantities and then packaged for sale to the consumer in small individual containers. The operation of filling the individual consumer containers with the bulk produced liquid is generally a fully automated operation in which the containers are sequentially passed through a filling station in which a group of downwardly projecting filler nozzles directs the liquid into the containers through upwardly facing container apertures.
One of the most common products so manufactured, marketed and distributed is engine lubricating oil which is processed in bulk quantities and usually packaged for sale in one quart containers. While the overwhelming majority of consumer containers for engine lubricating oil are of either one liter or one quart in volume, there has been a recent trend to also package and sell lubricating engine oil in four or five quart containers. In either event, the efficiency demands of the market place dictate that the container used be capable of easy and rapid filling and preferably be capable of multiple stacking in order to reduce shipping and storage costs. To date, these needs have for the most part been met with some success by the familiar one quart metal oil can which has a metal cylindrical container with flat top and bottom metal surfaces. To reduce weight and material costs, a hybrid container is widely used in which the top and bottom flat surfaces remain metal but the cylindrical side walls are made of a foil-coated pressed paper or cardboard material. Such containers are more subject to leakage than the all metal cans.
In either case, the packaging process essentially comprises initially combining the metal bottom metal portion and the side wall together and passing the can (minus its top) through the filling station of the process. Subsequently, the filled can is passed through a top assembly operation in which the metal top is attached by crimping or folding completing the sealing of the container. The familiar "oil can" container has persisted despite several disadvantages due primarily to the rapid filling made possible by the wide aperture offered by the can before its top is applied and the convenience of stacking offered by the flat, bottom and top surfaces of the oil cans.
Despite these two advantages, there remain, however, several disadvantages to the conventional oil can. For example, a special opener is required to remove the liquid from the can. Further, the construction is a three piece fabrication which results in a plurality of seams. This increases the possibility of leakage and greatly weakens the can's structure. The latter is particularly true in the case of the particle material side wall version of the can. In its most common use, that is, automotive engine lubricating oil, the small aperture through which engine oil is added to the crank case necessitates the use of a separate spout or funnel to avoid spilling.
These and other disadvantages of the commonly used oil can have spawned a great number of structures which include the use of a snap-on, reusable funnel which the consumer attaches to the upper side walls of the can once the can has been opened. Another structure uses a plastic bottle-like molded container in which the container top includes in a funnel shaped portion and an extending neck structure. In the latter case, a twist-off cap is also generally used to seal the neck.
While these structures provide some improvement in the consumer needs of easy access and resealability, the need for snap on funnels increases expense to the consumer and the molded containers with integral funnel and neck have the concomitant disadvantage of necessitating that fluid filling take place through the much smaller neck orifice of the container. This, of course, increases filling time and costs. Furthermore, such containers are usually impossible to stack for retail display and storage.
There remains therefore a need in the art for an inexpensive container which may be filled quickly, provides an integral pouring spout and is resealable and stackable.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a two-piece molded container in which the first piece is a generally cup-like container having side wall surfaces and bottom surface and defining a top aperture of substantially the same size as the side wall dimensions, and a second molded piece formed of a single molded unit including means for non-removably mating with the top aperture of the first piece. The means for non-removably mating the top with the container has a groove formed between an inner rim member and an outer wall member. This groove holds a central rim which is locked in the groove by the entry of a snap ridge held in a circular recess. The top has four integral members molded in a single continuous piece in which one of the members is common to all three of the remaining members and is separable therefrom by a tear-off operation. Once the tear-off piece has been removed, the remaining three members comprise a top surface, a spout movable between a retracted position and an extended position relative to the top surface, and a cap. The cap is removably mateable with the top surface when the spout is in a retracted position and, when so mated, holds the spout with respect to the top surface in the retracted position and seals the container.
BRIEF DESCRIPTION OF THE DRAWINGS
The Figures of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings in the several figures of which like reference numerals identify like elements, and in which:
FIG. 1 is a partially exploded elevation view of a container constructed in accordance with the present invention;
FIG. 2 is a plan view of the container of FIG. 1;
FIG. 3 is a partially sectioned view of the interface between respective tops and bottoms of the present invention containers;
FIG. 4 is a section view of a portion of the present invention container taken along the section line 4--4 of FIG. 1;
FIG. 5 is a partially sectioned view of the top portion of the present invention container with the spout extended;
FIG. 6 is a partially sectioned view of the upper portion of the container of the present invention in which the spout is retracted and the sealing cap is assembled.
FIG. 7 is an enlarged cross-sectional view of the outer wall of the upper portion of the container of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows the present invention container having a container bottom generally referenced by the numeral 10 and a top member generally referenced by the number 20. Container bottom 10 comprises a vertical side wall 11 resting upon a bottom 12 which is attached to side wall 11 by an integral ridge 13. Bottom 12 further defines a concave recess 15 generally centered within bottom 12, the importance and function of recess 15 will be described below in greater detail. Container bottom 10 further includes a ridge 14 joined to side wall 11 and a transition member 16 connected to an upper wall 17. As can be seen by reference jointly to FIGS. 1 and 2, side wall 11 has a generally square cross-section with rounded or filleted corners while upper wall 17 has a round cylindrical configuration. For this reason, transition member 16 is formed to provide a continuous surface between the more or less square shape of side wall 11 and the round cylindrical configuration of upper wall 17. Upper wall 17 further includes a rim 19 having a diameter slightly smaller than that of upper wall 17 and an inter-spaced groove 18 which in turn has a diameter less than both upper wall 17 and rim 19.
Top member 20 includes a cylindrical outer wall 22 and an upper surface 21 of generally flat configuration. Outer wall 22 and upper surface 21 are of circular configuration. In addition, outer wall 22 has an outer diameter approximately equal to that of upper wall 17 and an interior wall 24 which provides a smooth outer surface at the interface of the top 20 and the bottom 10 as shown in FIG. 3. Top member 20 further defines a circular interior rim 25 concentric with outer wall 22 and extending downwardly from the underside of upper surface 21 and terminating in an inclined surface 27. Top member 20 further defines a groove 23 concentric with outer wall 22, between wall 24 and rim 25. A snap ridge 26 extends inwardly from wall 24 of top member 20 and extends along the entire surface of wall 24. The shape of snap ridge 26 is shown in enlarged cross-sectional view in FIG. 7. Ridge 26 has an upper surface 44 which is at an angle "a" with respect to the horizontal. The bottom or lower surface 45 of ridge 26 is at an angle "b" with respect to the horizontal. Angle "a" is preferably between 5 and 25 degrees and ideally about 15 degrees. By the use of an angle in this range, the top will be securely held onto the bottom while still being able to snap into place when pushed onto the bottom. Angle "b" is less critical but ideally is about 45 degrees.
Top member 20 further defines a neck 31 centered on upper surface 21 with respect to outer wall 22 and a neck rim 32 extending outwardly a short distance beyond neck 31. Top member 20 further defines a cap 30 and a cap rim 34, the construction of which will be set forth below in greater detail. A tear-off ring 35 joins cap 30, spout rim 39 and neck rim 32.
While many features and aspects of the present invention are set forth below in greater detail, suffice it to say in connection with FIG. 1 that bottom container 10 and top member 20 are shown in partially exploded view prior to assembly of top member 20 upon container bottom 10. In the situation shown with reference to the above-described sequence of manufacture and filling for fluid merchandising above, once container bottom 10 has been filled, top member 20 is positioned overlying upper walls 17, groove 18 and rim 19 of container bottom 10, and is simply lowered to a position in which snap ridge 26 contacts rim 19 and incline 27 of rim 25 rests upon the interior surface of mouth 35 (shown in FIG. 2). Thereafter, a simple downward force, completes assembly. Top member 20 is pressed downwardly upon rim 19 causing rim 19 to spread incline 27 and rim 25 inwardly (away from wall 24) and to spread wall 24 away from rim 19 permitting snap ridge 26 to move across the outer surface of rim 19 and top member 20 to move downwardly bringing outer wall 22 closer to upper wall 17. At the point of travel in which rim 19 has moved into groove 23 a sufficient distance for snap ridge 26 to overlie groove 18 of upper wall 17, snap ridge 26 is urged into groove 18 and captivates rim 19 within groove 23 and the interior surface of rim 25. The resulting assembly will be set forth below and described in greater detail in the accompanying figures. However, suffice it to say here that what has been carried forth is a single one-step assembly in which container bottom 10 and upper surface 21 are irremovably assembled and in which snap ridge 26, groove 23, and rim 25 captivate rim 19 against wall 24 and maintain a compression fit to assure proper sealing of the resulting container enclosure.
As set forth above and in accordance with an important aspect of the present invention, the two piece construction of the present invention container permits rapid filling of container bottom 10 through the large aperture presented by mouth 46 comparable in efficiency with the traditional oil can. Furthermore, the easy assembly of top member 20 to bottom container 10 produces a sealed integral structure with only a single seam and virtually no assembly costs. Top member 20 is depicted in FIG. 1 as it would appear prior to opening by the consumer. The combined structure of cap 30, neck 31 and neck rim 32 together with tear-off ring 35 and tab 33 extends above upper surface 21 a relatively small distance.
The importance of this short extension of the neck and cap structure depicted in FIG. 1 is better understood by reference to FIG. 3 in which the cap, neck, and tear-off ring structure of FIG. 1 is repeated and in which there is shown a similar container stacked upon upper surface 21 of top member 20. It is important to note that recess 15 in the top container permits bottom 12 thereof to rest upon upper surface 21 of the lower container. Further, recess 15 extends upwardly into container bottom 10 far enough that cap 30 does not touch recess 15. In other words, prior to removal of tear-ring 35, that is consumer opening, the present invention containers may be stacked in multiple vertical levels. In addition, the cooperation of recess 15 of the upper container and the protruding portions formed by cap 30, tear-off ring 35 and neck 31 of the lower container cooperate to provide nested stacking of the present invention containers in which the alignment of stacked containers is maintained and sliding of bottom 12 of the upper container across upper surface 21 of the lower container is minimized.
The partially sectioned portions of top member 20 shown in FIG. 3 show the combined structure, described above, after top member 20 has been joined to container bottom 10. As mentioned above and shown clearly in FIG. 3, once joined by the foregoing method, container bottom 10 and top member 20 are mated irremovably and maintained in a sealed position by the intrusion of snap ridge 26 into groove 18 and the outward urging of rim 25 against rim 19. As can be seen, the resulting structure provides a single container seam having substantial certainty of proper sealing between top member 20 and container bottom 10, and a strong container structure.
Turning now to FIG. 4 in which a full section view of the upper portion of the present invention container in the assembled position is shown. The details of the above-described assembled structure of rim 19 resting within groove 23 and being maintained by the combined actions of rim 25 and snap ridge 26 are repeated. In addition and in accordance with an important aspect of the present invention, top member 20 is formed of a single molded component. Outer wall 22 and upper surface 21 form the container top and top member 20 further defines a circular neck portion 31 which terminates in an outwardly extending neck rim 32 the reasons for which are set forth below. Top member 20 further defines a spout aperture 38 which for reasons described below in greater detail and has a diameter slightly greater than spout 40. Top member 20 also defines a cap 30 which includes a cap surface 37 and a cap sealing rim 36 together with a cap rim 34. As can be seen by examination of FIG. 4 and briefly turning to FIG. 6, cap 30 is, prior to removal of tear-off ring 35, in essence resting in an inverted position from its normal relationship to neck 31 and neck rim 32 when the present invention container is resealed. Returning now to FIG. 4, top member 20 further includes a circular cross-section elongated spout 40 which terminates at its upper end in an extended spout rim 39 and at its lower end in a stop ring 43 both of which extend outwardly from spout 40. The lower end of spout 40 also defines a snap ridge 41 and a seating wall 42 between snap ridge 41 and stop ring 43. Snap ridge 41 has a diameter slightly greater than that of spout 40. The importance of this increased diameter will be set forth below in greater detail. As is shown in FIG. 4 and mentioned above, spout 40, cap 30, upper surface 21, tear-off ring 35 and tab 33 are all formed of a single piece of molded plastic material. It should also be noted that tab 33 and tear-off ring 35 are the only members having common surfaces between cap 30, spout rim 39 and neck rim 32. This construction is in accordance with an important aspect of the present invention. As configured in FIG. 4, the entire assembly of cap 30, spout 40, tear-off ring 35 and neck 31 presents a one piece sealed structure in which fluid is sealed within the container and in which spout 40 is maintained in its retracted position. In other words, the present invention container top member 20 is molded of a single piece of plastic material and is shown in FIG. 4 in the configuration which would be presented to the consumer upon receiving the filled container with its seal intact. Tear-off ring 35 forms a flat ribbon which surrounds the top of sprout 40 and which is removable by pulling on tab 33. In order to open the present invention container and gain access to the liquid contained therein, the consumer need only grasp tab 33 and pull it causing tear-off ring 35 to simultaneously separate from neck rim 32, spout rim 39 and cap rim 34 of cap 30. With this separation, spout 40, neck 31 of upper surface 21 and cap 30 are mutually separated one from the other permitting spout 40 to be drawn to its extended position.
FIG. 5 is a partially sectioned view of the upper portion of the present invention container as it appears just after tear-off ring 35 and tab 33 have been removed from the structure shown in FIG. 4 and after spout 40 has been pulled to its extended position. During movement of spout 40 to its extended position, snap ridge 41 is pulled through spout aperture 38 until it passes above neck rim 32. While snap ridge 41 is larger than spout aperture 38, the elasticity of neck 31 and neck rim 32 permits them to expand allowing the larger diameter snap ridge 41 to pass through spout aperture 38. Once snap ridge 41 emerges from spout aperture 38, neck rim 32 and neck 31 close around seating wall 42 of spout 40. As mentioned above, seating wall 42 is a larger diameter than spout 40. This produces a seal between aperture 38 and sealing wall 42. Complete withdrawal of spout 40 from the present invention container is precluded by the extended surface of stop ring 43 which abuts the underside of upper surface 21 and is large enough to preclude passage through aperture 38. Thus, the structure in FIG. 5 shows spout 40 extended and maintained in its extended position by the combined actions of snap ridge 41 and stop ring 43 captivating neck rim 32 and neck 31.
At this point, the consumer may tip the container to an inverted or inverted and inclined position and pour the desired amount of liquid from the container interior into the filler orifice of the automobile engine or any other desired receptacle. In the event the entire contents of the present invention container are not emptied out, the consumer may retract the container spout by simply forcing spout 40 downward with respect to upper surface 21. This causes snap ridge 41 to force neck rim 32 and neck 31 outwardly and to pass through spout aperture 40. Once snap ridge 41 clears spout aperture 38, spout 40 will easily move downwardly until spout rim 39 rests upon neck rim 32.
Closure of the container is best understood by turning to FIG. 6 which shows the relative positions of spout 40 and top member 20 once spout 40 has been pushed all the way down to its retracted position and spout rim 39 rests upon neck rim 32. At this point, the consumer may reseal the present invention container by simply taking cap 30 and inverting it from its original position and placing it such that cap sealing rim 36 overlies neck rim 32. Thereafter, a downward force upon cap 30 will cause cap sealing rim 36 to slide over neck rim 32 and rest against neck 31. As a consequence, cap 30 is maintained by the resilient action of cap sealing rim 36 captivating neck rim 32. In addition, because spout ring 39 lies between neck rim 32 and cap surface 37 of cap 30 when spout 40 is retracted fully, the resilient grasp of cap sealing ring 36 upon neck rim 32 maintains a compression force upon spout ring 39 captivating it between cap surface 37 and neck rim 32. This compressive captivation of spout ring 39 accomplishes an important aspect of the present invention in which the resealed configuration shown in FIG. 6 forms a reliable liquid-tight seal which may be repeatedly opened and resealed.
The inventive structure shown embodies a structure using a rigid spout member which is moved between an extended and retracted position. It will be apparent to those skilled in the art, however, that equivalent structures for extending and retracting such a spout may be substituted without departing from the spirit and scope of the present invention. For example, rather than the rigid slideable member shown, spout member 40 may instead be a deformable member in which a continuous accordian-like wall extends from the bottom of the spout member to the adjoining portions of the upper container.
What has been shown is a molded plastic container suitable for use in storing, distributing and merchandising liquid material in which a resealable inexpensive container is formed.
Further, it will be apparent to those skilled in the art from the foregoing disclosure that the present invention container described herein has numerous advantages. For example, the entire structure of top member 20 including spout 40, cap 30 and neck 31 and upper surface 21 together with tear-off ring 35 are formed of a single continuous molded piece which upon removal of the tear-off ring is divided into several separate members. This structure is extremely advantageous in mass distribution of liquids such as engine oil in which the ease of consumer opening of the container and the reliability of the seal prior to distribution to the consumer is of great concern. Further, the container of the present invention, because of its two-piece structure, permits the rapid filling of container bottom 10 through the large orifice of mouth 46 rather than through the smaller orifice of spout 40. This, of course, produces a container which may be quickly and efficiently filled thereby meeting manufacturers' needs and which once assembled by simple snap-type operation then presents to the consumer all the advantages of easy pouring etc. available in the prior art structures in which a funnel neck is provided.
The present embodiments of this invention are thus to be considered in all respects as illustrative and not restrictive; the scope of the invention being indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
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A molded plastic container includes a one-piece bottom portion having a cylindrical mouth and a one-piece top portion having an extendable center spout and raised neck. The spout is held within the neck and moveable between extended and retracted positions. The container is filled through the cylindrical mouth after which the top and bottom portions are non-removeably joined. Initially, the spout, neck and cap are joined by a removeable tear-off ring which seals the container. Once the tear-off ring is removed, the spout is free to move between extended and retracted positions, and the cap may be placed on the neck to hold the spout in its retracted position and reseal the container.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of the filing date of U.S. Provisional Application No. 61/644,384 filed on May 8, 2012.
FIELD OF THE INVENTION
[0002] The invention relates to systems and methods for control and operation of electronic access devices in commercial, residential, industrial, storage, medical, and other facilities that can be monitored and controlled remotely through a computer system that selectively wakes the access devices via a radio signal from a radio frequency bridge device connected to the computer system, and the access devices are further selectively connected to the computer system with a wireless fidelity (WI-FI) connection for data transmission when waked with the radio signal.
BACKGROUND
[0003] Existing electronic lock systems are used to control access to various areas within a facility. Some systems employ wireless locks that communicate with an interface device that is in sufficient proximity to the electronic locks to enable radio communication. The various interface devices are hardwired to a central database that is connected to the computer system of the facility. The computer system provides updates to the electronic locks through this radio communication network. However, the hardwired connection of the interfaces devices with the access control device can be expensive in large facilities, and creates concerns that the hardwiring is redundant with the existing wiring of the various area networks of the facility.
[0004] Some electronic lock systems leverage the existing WI-FI and other networks of the facility to communicate with the electronic locks so that programming and/or data can be transmitted to each lock without requiring separate updates for each lock. However, WI-FI systems are employed off-line, meaning that communication between the computer system and the electronic locks is only established at predetermined intervals to preserve battery life of the electronic locks, which are desired to operate for several years between battery changes. Therefore, further improvements in this area of technology are desired.
SUMMARY
[0005] In one aspect, there is disclosed systems and methods for controlling one or more access devices using WI-FI and radio frequency networks connected to an access control device. The systems and methods provide real-time communications between the access devices and the access control device, which includes software and a database for updating of credentials, software, and other aspects of each access device while preserving battery life of the access device. The systems and methods can also be operated in an off-line mode where communication between the access control device and the access device is established at predetermined intervals. These and other aspects, features, forms, embodiments, objects, and advantages are also discussed below with reference at least in part to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a diagram of a system for connecting a computer network to a plurality of access devices with a radio frequency (RF) bridge device and/or a WI-FI connection to allow on-line and off-line remote monitoring and control of the access devices from an access control device.
[0007] FIG. 2 is a block diagram of the system of FIG. 1 .
[0008] FIG. 3 is a block diagram of an access device that is configured for dual frequency communication with the computer network of FIG. 1 .
[0009] FIG. 4 is a block diagram of the radio frequency bridge device of FIG. 1 .
[0010] FIG. 5 is a block diagram of the system of FIG. 1 showing on-line communications protocols between the access control device, the radio frequency bridge device, and the access control device.
[0011] FIG. 6 is a flow diagram of the sleep and wake modes of operation of the access devices of FIG. 1 .
[0012] FIG. 7 is a flow diagram of a sleep mode of operation of the access control device of FIG. 1 .
[0013] FIG. 8 is a flow diagram of a wakeup mode of operation for the access control device of FIG. 1 .
[0014] FIGS. 9A and 9B are a flow diagram of an initialization procedure for the access control device.
DETAILED DESCRIPTION
[0015] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
[0016] Systems, devices and methods are disclosed for remote monitoring and control of access devices that are connectable to a WI-FI network and to a radio frequency network. The access devices can be located in or on, for example, a commercial building, industrial facility, medical facility, residential building or facility, hotel or resort facility, a residence, a storage facility, or other structure or group of structures. In one form, the access devices are configured to work with one or more bridge devices that provide RF communication with the access devices, with the bridge device(s) and access devices integrated into the computer network of the facility to leverage the facility's WI-FI network and allow real time communications between an access control database and selected access devices in order to minimize power consumption of the access devices for which communication is not needed.
[0017] FIG. 1 illustrates an access control system 10 that monitors and controls electronic access devices 20 including but not limited to electronic door locks. Access devices 20 may also include or alternatively be any one or more of deadbolts, cameras, lights, temperature controls, appliances, and the like. The system 10 includes a computer network 12 that can be coupled to an access control device 30 , which includes a database and software for operating the access control system. Computer network 12 can be any one or combination of wired local area network, a wireless area network, or the internet. Computer network 12 can further include a routing device 14 . At least one RF bridge device 16 couples an RF network 24 to the computer network 12 . In one embodiment, bridge device 16 is connected to computer network 12 with an Ethernet cable or other suitable connection with routing device 14 .
[0018] FIG. 1 illustrates a plurality of access devices 20 in the form of door locks, e.g. for use on an entrance door of a building, room or other part of a structure, that is configured to receive RF signals as part of the RF network 24 and that are also configured to send and receive signals to computer network 12 via a WI-FI connection 26 . However, it should be understood that many other devices can send and receive RF signals as part of the RF network 24 and WI-FI connection 26 and the illustrated door lock is simply an example of one of these devices.
[0019] In the RF network 24 , each connected device 20 acts as a communication node that can receive a radio signal as a wakeup signal from access control device 30 through its assigned bridge device 16 , and then communicate to send and receive information packets via WI-FI connection 26 with computer network 12 to other devices in the system 10 , such as access control device 30 . If a wakeup signal is not addressed to the access device 20 in RF network 24 , the access device 20 ignores the wakeup signal. If the particular wakeup signal is addressed to the access device 20 that interrogates it, the access device 20 is awakened from a sleep mode and operates in a wake or run mode to communicate with access control device 30 through the WI-FI connection 26 with computer network 12 . In this arrangement, the battery operating life of each access device 20 is maintained since only access devices 20 that are designated to receive information from access control device 30 are awakened in real time for information downloads and information uploads. The interrogation of the wakeup signal by access device 20 occurs in conjunction with radio frequency communications, increasing battery life since the bridge device 16 transmits RF signals and the RF receiver of the access device 20 can operate at a lower power level when compared to standard wireless networks.
[0020] Referring further to FIG. 2 , in one construction, the RF network 24 communicates via a sub-1 GHz beacon with each of the access devices 20 in the radio network through an assigned bridge device 16 . In systems 10 with multiple bridge devices 16 having access devices 20 assigned to respective ones thereof, access control device 30 can identify which bridge devices 16 connected to computer network 12 to alert in order to send a wakeup signal to only a portion of access devices 20 in the system 10 . The wakeup signal enables WI-FI communication of the awakened access device 20 with access control device 30 through WI-FI connection 26 , which handles large data volumes more efficiently. Access device 20 downloads information packets from and transmits information packets to access control device 30 via WI-FI connection 26 with computer network 12 .
[0021] The exemplary access device 20 shown in FIG. 1 is a door lock, which is further shown in a block diagram form in FIG. 3 . The access device 20 includes a logic and memory module 40 , a suitable power source 42 , such as A/C power and/or battery power, a keyless entry system 44 , a keyed entry mechanism 46 , a locking mechanism 48 , a multi-frequency transceiver 50 , and a user interface 52 .
[0022] The keyless entry system 44 includes a keypad 44 a for entering an access code and other data. In other constructions, other data entry systems may be used in place of the keypad, such as biometric entry, smart cards, infrared readers, etc. Keyless entry system 44 may also or alternatively include a card reader for electronically reading an access code from a card carried by the user. The keyless entry system 44 communicates with the logic and memory module 40 that stores access codes and other user identification information and for carrying out the functions of the access device 20 . The logic and memory module 40 may store individual user codes, where each person having access to the door is issued a unique user code that is stored and compared to input codes at the door to allow access decisions to be made at the door without transmissions over computer network 12 . In one embodiment, logic and memory module includes a processor that drives communications with RF network 24 and establishes WI-FI connection 26 through appropriate hardware on access device 20 and bridge device 16 . The logic and memory module 40 may further include an internal memory for storing credential data and audit data, and a real-time clock for determining times associated with access events. In addition, logic and memory module 40 is operable in a low power mode to preserve battery life. In one specific embodiment, logic and memory module 40 includes an advance reduced instruction set computer machine.
[0023] The keyed entry mechanism 46 can manually operate the locking mechanism 48 , for example in case of power loss or other malfunction. The locking mechanism 48 of the access device 20 may include a locking device such as a sliding deadbolt, or other suitable locking mechanism coupled to a door handle or knob and/or to a key mechanism. In the illustrated construction, the locking mechanism 48 is power-driven, for example by a solenoid or an electric motor, to facilitate remote operation. The access device 20 may also include user interface 52 having visual components, such as an LED light and/or an LCD screen, and/or audio components, such as a speaker or other sound-generating device.
[0024] Where the access device 20 is part of a networked system 10 such as that described herein, functions that can be performed remotely through access control device 30 include, but are not limited to, confirming the status of a lock, such as whether the door lock is locked or unlocked, notifying the network of an attempted access, including whether the lock was accessed, when it was accessed and by whom, whether there were attempts at unauthorized access, and other audit information. In some constructions, the access device 20 can also receive and execute a signal to unlock the lock, add or delete user codes for locks having such codes, and, if the door lock is paired with a suitable camera (not shown), transmit images of the person seeking entry. The access device 20 can also be used to send a command to disarm an electronic alarm or security system, or to initiate a duress command from the keypad 44 a of the access device 20 , where the duress command may be utilized by the network to transmit a message to access control device 30 or other linked device, such as a computer terminal or mobile device, an electronic alarm or security system, or a networked computer server.
[0025] The access device 20 can be a self-contained functional lock such as an electronic lock used to secure an access point. Access device 20 includes an electronically-controlled system containing a keypad 44 a, logic-memory module 40 , and an electro-mechanical locking mechanism 48 . Using the keypad 44 a, a user can enter a numeric access code to activate the electro-mechanical locking mechanism 48 thus unlocking the door controlled by access device 20 . The keypad 44 a can also be used to program and configure the operation of the access device 20 , such as adding access codes, deleting access codes, enabling audible operation, and setting relocking time delays. Additionally, the access device 20 includes multi-frequency transceiver 50 , or interface, that can include an RF module 50 a such as an antenna or programmable card for the reception and transmission of sub 1-GHz RF signals, a WI-FI module 50 b configured to establish WI-FI connection 26 to and send and receive WI-FI signals to computer network 12 , and all necessary electronic components required for the reception and generation of RF signals and WI-FI connection/disconnection with logic-memory module 40 . The WI-FI interface with access control device 30 provides the same operation, programming, and configuration functionality as that afforded by the keypad 44 a, in addition to a wide range of features including but not limited to audit information such as lock status reporting, lock operation reporting, lock battery status, and the like.
[0026] FIG. 4 is a block diagram of the RF bridge device 16 . The bridge device 16 includes a transceiver module 60 , such as a power over Ethernet (PoE) receiver for sending and receiving signals to and from the computer network 12 via connection 18 via transmission control protocol/internet protocol (TCP/IP). Bridge device 16 also include a network interface card 62 connected to transceiver module 60 . Network interface card 62 is connected to a microcontroller 64 and an RF transmitter 66 . RF transmitter 66 receives commands from microcontroller 64 and provides output of RF signals over RF network 24 . Bridge device 16 may also include a power source 68 and a user interface (not shown) for inputting information and obtaining status. Other transmission protocols besides Internet Protocol can also be employed to communicate with the computer network 12 .
[0027] The RF transmitter 66 is suited for communication at the appropriate RF network frequency, for example sub-1 GHz, although other frequencies can be used as well. The RF transmitter 66 formats the RF signals it transmits according to the communications protocol that is being used. The RF bridge device 16 may include an antenna 17 ( FIG. 1 ), which can be contained within the housing of the bridge device 16 or may be external to the housing. The transceiver module 60 formats the signals it sends according to the communications protocol, e.g. Internet Protocol, used to connect the computer network 12 . In one construction, the RF bridge device 16 connects to a local-area network (LAN) via an Ethernet connection 18 , although other types of connections are possible. As shown in FIG. 1 , the connection 18 includes a cable having a plug to connect to an Ethernet port on a router 14 . As illustrated in FIG. 1 , the router 14 can include wireless Internet Protocol signaling to communicate with suitable wireless-compatible devices such as access devices 20 . The transceiver module 60 may alternatively connect to a wireless router 16 using a wireless connection, for example using an IEEE 802.11x-based wireless networking protocol. The power source 68 of bridge device 16 can be a battery or other portable power supply, or an alternating current (A/C) or other fixed power source, or both. The user interface can include input mechanisms such as one or more buttons and an output mechanism such as a screen or indicator lights.
[0028] The microcontroller 64 can be any suitable logic-memory unit configured to coordinate the various functions of the RF bridge device 16 as discussed herein. The micro-controller 64 coordinates transfer of signals between the RF network 24 and the computer network 12 . The microcontroller 64 translates signals from the transceiver module 60 into commands that the RF transmitter 66 broadcasts to the RF network 24 to access devices 20 . The microcontroller 64 may also translate signals into commands for the transceiver module 60 to transmit to the computer network 12 .
[0029] FIG. 5 illustrates additional details of the communications protocols of system 10 of FIG. 1 . Access control device 30 is connected to transceiver module 60 of bridge device 16 with at least one of computer network 12 , router 14 and Ethernet connection 18 for two-way communication. Transceiver module 60 is connected to RF transmitter 66 to provide RF signals over RF network 24 . Each of the access devices 20 is connected to RF network 24 with RF module 50 a to receive and interrogate a wakeup signal. RF module 50 a is connected with logic-memory module 40 of access device 20 so that when a RF signal that is targeted to access device 20 , access device 20 enters a wakeup mode of operation. In the wakeup mode, logic-memory module 40 activates WI-FI module 50 b, which connects to computer network 12 via WI-FI connection 26 for two-way communication. Additional communications protocols are also contemplated and not precluded. For example, one or more remote devices, such as a networked computer and a mobile device, can connect to access control device 30 for access to computer network 12 .
[0030] Access control device 30 can be, for example, a networked computer that is connected with computer network 12 , and that can communicate with a mobile device or networked computer using HyperText Transfer Protocol (HTTP) commands or other protocols suited for use via the Internet or other connection, with appropriate web-browsing or other software being loaded on the mobile device or networked computer. Access control device 30 can include a database with, for example, user identifications, access device identifications, access device credentials, access device audit data, and programmed with software to manage the database information. Access control device 30 can further include software with user interface features that facilitate user operation of access control device 30 to view access device status, manage and update access devices 20 with programming, user credentials, and override commands, and to receive audit data from access devices 20 .
[0031] FIG. 6 shows a flow diagram for a power state transition procedure 100 of access control device 20 . Any reset operation 102 that provides an input to access device 20 can cause access device 20 to reset, and in particular logic-memory module 40 , to enter a wakeup or run mode 104 . Reset operation 102 can include a number of wakeup sources such as, for example, an entry of an access code to access device 20 , reading of an access card by access device 20 , an RF signal interrupt received by access device 20 , a real time clock interrupt programmed into access device 20 , tampering of access device, 20 , or receipt of a data packet by access device 20 over WI-FI-connection 26 and/or RF network 24 . After a predetermined time of inactivity, access device 20 transitions to a sleep mode 106 , where logic-memory module 40 shuts down WI-FI connection 26 , suspends all tasks relating to wireless operation, and shuts down power to WI-FI module 50 b. In one embodiment, sleep mode 106 is a deep sleep mode with a low leakage stop (LLS) that provides a low level of power to enable wakeup operations, memory retention, and state retention of peripherals while preventing peripheral operation in the sleep mode. Other power retention and shutdown schemes are also contemplated so long as adequate battery life is preserved and/or power consumption is minimized for access device 20 . When a wakeup signal is received over RF network 24 , access device 20 returns to wakeup operation under run mode 104 and powers WI-FI module 50 b to establish WI-FI connection 26 and power up logic-memory module 40 . The run mode 104 can include a low leakage wakeup module that flags the wakeup source and logs the wakeup source and time in memory of logic-memory module 40 .
[0032] FIG. 7 shows a flow diagram for one embodiment of a procedure 200 for entry of access device 20 to sleep mode 106 . Procedure 200 begins at sleep mode indicator 202 and continues at conditional 204 in which an operating mode of access device 20 is determined. In one embodiment, access device 20 is operable in either an on-line mode or an off-line mode. The on-line mode discussed hereinabove provides real time communications between access control device 30 and access devices 20 through WI-FI connection 26 by providing a wakeup signal over RF network 24 to the particular access devices 20 targeted for communication by access control device 30 . As a result, access devices 20 can be updated in the on-line mode with user credentials and other information in real time by pushing the data to the targeted access devices 20 whenever desired. Battery life of access devices 20 is preserved and/or power consumption is minimized since access devices 20 can otherwise remain disconnected from computer network 12 by shutting down WI-FI connection 26 in the sleep mode.
[0033] In FIG. 1 , certain access devices 20 , designated as access devices 20 ′ in FIG. 1 , are configured to operate in an off-line mode since they are not connected to or operable to receive radio signals transmitted over RF network 24 . Rather, access devices 20 ′ are configured to communicate with access control device 30 solely through wireless connections 22 when the wireless connection is established. In order to preserve battery life and/or minimize power consumption, access devices 20 ′ only establish WI-FI connections 22 at predetermined intervals, such as once a day, to receive updates of user credentials and other data, from access control device 30 .
[0034] Referring back to FIG. 7 , in procedure 200 if it is determined at conditional 204 that access device 20 is to operate in an off-line mode, procedure 200 continues at operation 206 in which an alarm is set that establishes a predetermined time or time interval for access device 20 to wake up and connect to computer network 12 for updates through WI-FI connection 26 . If it is determined at conditional 204 that the access device 20 is to operate in an on-line mode, no alarm is set. Procedure 200 continues at operation 208 to shut down WI-FI module 50 b and the WI-FI connection 26 . Procedure 200 then continues at operation 210 where access device 20 enters a sleep mode until a wakeup signal is received, either via alarm or by an RF signal, depending on whether access device 20 is operating in an off-line mode or an on-line mode, respectively. Procedure 200 then continues at operation 212 where access device 20 continues in a wakeup mode of operation to communicate with computer network 12 and access control device 30 trough WI-FI connection 26 .
[0035] Referring now to FIG. 8 , there is shown a flow diagram for a wakeup procedure 300 for operation of access device 20 and system 10 in the on-line mode discussed above. Procedure 300 begins upon receipt of a wakeup signal at one or more of the access devices 20 . At conditional 304 the wakeup source is determined. If the wakeup source is from keyless entry system 44 , such as an entry to a reader of access device 20 , an access code entered by keypad 44 a, or an input/output (I/O) change from entry system 44 or logic-memory module 40 to change settings associated with access device 20 , procedure 300 continues at conditional 306 to identify whether the wakeup source is a credential entry or an I/O change. If the wakeup source is associated with a credential entry, procedure 300 continues at operation 308 to search for the credential in the data stored in logic-memory module 40 . Procedure 300 continues at conditional 310 to determine if the credential is found. If the credential is found at operation 308 , procedure 300 continues at operation 318 where logic-memory module 40 sends a motor control command to open locking mechanism 48 of access control device 20 . Procedure 300 then continues at operation 320 to update audit data associated with the unlocking of access device 20 . Such audit data can include, for example, the identification of the access device, identification of the user credentials, and time of access. Alternatively, if at conditional 310 a user credential is not identified on the database of access device 20 , procedure 300 proceeds directly to operation 320 to update audit data to record the time of attempted access with the access control device 20 . After updating the audit data in logic-memory module 40 at operation 320 , access control device 20 returns to sleep mode 328 .
[0036] If at conditional 306 it is determined that the wakeup source is an I/O change, notification of the change is provided. Procedure 300 continues to operation 320 to update the audit data indicating, for example, the time of the I/O change and the particular I/O change that was made. After updating the audit data in logic and memory unit 40 at operation 320 , access control device 20 returns to sleep mode 328 . If the wakeup source determined at conditional 304 is from an access code entry or input/output (I/O) change WI-FI connection 26 is not established with computer network 12 , preserving battery life of access device 20 .
[0037] If at conditional 314 it is determined that the wakeup source was initiated by a radio signal from RF network 24 , procedure 300 continues at operation 312 and access device 20 receives the radio signal and reads the packet transmitted to the access device 20 . Procedure 300 continues at conditional 304 and determines the type of packet received by the access control device 20 . If the packet is a wakeup signal indicating a download from access control device 30 is requested, access control device wakes up and restarts to power WI-FI module 50 b at operation 324 . The data from access control device 30 is then downloaded over WI-FI connection 26 at operation 326 to logic-memory module 40 . Furthermore, audit data stored in logic-memory module 40 of access control device 20 is downloaded to access control device 30 . Upon completion of downloads at operation 326 , access control device 20 then returns to sleep mode 328 .
[0038] If at conditional 304 it is determined the packet is a lock/unlock command from access control device 30 , procedure 300 continues at operation 318 and logic-memory module 40 sends a motor control command to locking mechanism 48 to lock or unlock the lock of access control device 20 . In one embodiment, the lock command is a command that over-rides user credentials and prevents any unlocking of access device 20 . Procedure 300 then continues at operation 320 to update audit data associated with the locking and/or unlocking of access device 20 . After updating the audit data in logic and memory unit 40 at operation 320 , access control device 20 returns to sleep mode 328 . If is determined at conditional 304 the packet is a lock/unlock command from access control device 30 , WI-FI connection 26 is not established with computer network 12 , preserving battery life of access devices 20 .
[0039] For operation of access device 20 in an off-line mode, procedure 300 is modified since a radio signal from RF network 24 is not interrogated by access device 20 . Rather, at conditional 304 , if the modified procedure determines the wakeup source is from entry system 44 or I/O change, the procedure continues as discussed above. If the wakeup source is determined to be the alarm settings of access device 20 , wireless module 50 b is automatically powered on and connected to computer network 12 via WI-FI connection 26 to receive data download from access control device 30 and to transmit audit data to access control device 30 through WI-FI connection 26 .
[0040] Referring now to FIGS. 9A and 9B , one example of a boot-up procedure 400 for access control devices 20 is shown. Boot-up procedure 400 begins at 402 upon initial power on or reset of the access control device 20 . Procedure 400 continues at operation 402 and initializes the hardware of access device 20 . Operation 402 also configures the wakeup interrupts that can be used based on the operating mode for access device 20 , either on-line or off-line as discussed above. Procedure 400 continues at operation 406 and further configures the access device identification, the internet protocol address required to communicate with the access control device 30 , and the logic-memory module 40 of access device 20 . Procedure 400 then continues at operation 408 to start the access device connection client with access control device 30 , and to connect with access control device 30 . The starting of the connection client may include, for example, opening a TCP/IP client connection for communication with computer network 12 through WI-FI connection 26 .
[0041] Procedure 400 continues at conditional 410 to determine if access device 20 is connected to access control device 30 . Once access device 20 is connected, procedure 400 continues at operation 412 and retrieves the operating mode (on-line or off-line) and synchronizes with the access control software on access control device 30 . Via a download 414 , procedure 400 continues at operation 416 where the user and credential data is downloaded from the access control device 30 and stored in internal memory of logic-memory module 40 . At conditional 418 , it is determined if the download is successful. If the download 414 fails, a database error is indicated at output 420 and procedure 400 stops at 422 . If download 414 is successful, procedure 400 continues at operation 424 to upload audit data to access control device 30 . At conditional 426 it is determined whether the upload is successful. If the upload fails, procedure 400 continue by indicating a connection failure 428 with the access control device 30 , and procedure 400 stops at 430 . If the upload is successful, procedure 400 continues where access control device 20 enters a sleep mode at 432 for saving power.
[0042] According to one aspect, a method includes transmitting a first signal from an access control device via a first network to a radio frequency bridge device; in response to the first signal, transmitting a wake up signal from the radio frequency bridge device to at least one electronic access device that is operating in a sleep mode; waking the at least one electronic access device from the sleep mode in response to receiving the wake up signal; wirelessly connecting the electronic access device to the first network with a WI-FI connection in response to waking the at least one electronic access device with the wake up signal; and transmitting operating parameters to the electronic access device from the access control device through the WI-FI connection with the first network.
[0043] In one embodiment, the method includes updating the electronic access device with user credentials that authorize one or more users to unlock the electronic access device and/or updating software of a logic and memory unit of the electronic access device. In another embodiment, the method includes unlocking or locking the electronic access device in response to an unlocking command or a locking command, respectively, associated with the wake-up signal. In yet another embodiment, the method includes transmitting a second signal from the electronic access device to the access control device through the WI-FI connection with the first network. In a refinement of this embodiment, the second signal includes at least one of: whether the electronic access device is locked or unlocked, whether the electronic access device has been accessed, an identity of a user who has accessed or attempted to access the electronic access device, and whether a distress code has been entered.
[0044] In another embodiment, the method includes configuring a plurality of electronic access devices to interrogate the wake up signal. In one refinement of the embodiment, only a portion of the plurality of electronic access devices wake in response to interrogating the wake up signal from the radio frequency bridge device. In a further refinement, each electronic access device of the portion of the plurality of electronic access devices that wake wirelessly connect to the first network through the WI-FI connection in response to receiving the wake up signal. In another refinement of the embodiment, the first network is a local area network and further comprising connecting the local area network to the radio frequency bridge device with an Ethernet connection.
[0045] In another aspect, a system is disclosed. The system includes an access device with a locking mechanism movable between a locked and unlocked position, a keyless entry system operably connected to the locking mechanism, a logic and memory module connected to the keyless entry system, a multi-frequency transceiver connected to the logic and memory module, and a power source. The system also includes a radio frequency bridge device with a radio frequency transmitter and a transceiver configured to receive signals from a computer network. The transceiver is operatively connected to the radio frequency transmitter to cause the radio frequency transmitter to output a radio signal in response to the signals from the computer network. The multi-frequency transceiver of the access device is configured to receive the radio signal from the transmitter. The system also includes an access control device operatively connected to the computer network. The access control device includes a database with user credentials and access device identification information. The access control device is configured to transmit the signals over the computer network to the radio frequency bridge device, and the access control device is further configured to transmit database information to the access device via a WI-FI connection of the multi-frequency transceiver of the access device to the computer network. The WI-FI connection is established in response to the access device interrogating the radio signal from the radio frequency bridge device.
[0046] In one embodiment, the access device further includes a user interface. In another embodiment, the access device includes a keyed entry mechanism for manually operating the locking mechanism. In yet another embodiment, the keyless entry system includes a keypad for entering an access code to the logic and memory module. In a further embodiment, the multi-frequency transceiver includes a radio frequency module configured to receive the radio signal from the radio frequency bridge device and a WI-FI module configured to establish a WI-FI connection with the computer network in response to interrogation of the radio signal.
[0047] In another embodiment, the transceiver of the radio frequency bridge device is an internet protocol transceiver. In yet another embodiment, the radio frequency transmitter is configured to transmit the radio signal at sub-1 GHz. In another embodiment, the system includes a router connecting the radio frequency bridge device with the computer network. In a further embodiment, the power source of the access device is a battery. In another embodiment, the radio frequency bridge device includes a network interface card connected to the transceiver and a microcontroller connected to the radio frequency transmitter and the network interface card.
[0048] In another aspect, a system is disclosed that includes a computer network and a plurality of access devices. The computer network includes an access control device with a database including at least user credentials and access device identification information. The computer network also includes a wireless routing device connected to the access control device and to a radio frequency transmitter configured to transmit a radio signal. The access devices each include a locking mechanism movable between a locked and unlocked position, a keyless entry system operably connected to the locking mechanism, a logic and memory module connected to the keyless entry system, a multi-frequency transceiver connected to the logic and memory module, and a power source. The multi-frequency transceiver is operable to receive the radio signal from the radio frequency transmitter to transition the access device from a sleep mode of operation to a wake mode of operation. When in the wake mode of operation the multi-frequency transmitter is configured to establish a WI-FI connection with the wireless routing device for data transmission between the access device and the access control device.
[0049] In one embodiment, the multi-frequency transmitter includes a radio frequency module that is configured to interrogate the radio signal before transitioning the access device from the sleep mode of operation to the wake mode of operation. In another embodiment, the access control device is configured to identify a portion of the plurality of access devices and configure the radio frequency transmitter to transmit the radio signal to targeted access devices. In yet another embodiment, the radio frequency transmitter is part of a bridge device that is connected to the routing device with an Ethernet connection. In a further embodiment, the multi-frequency transceiver of each of the plurality of access devices is operable to receive the radio signal from the radio transmitter and unlock or lock the access device in response to the radio signal.
[0050] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the certain embodiments have been shown and described and that all changes and modifications that come within the spirit of the inventions are desired to be protected. It should be understood that while the use of words such as preferable, preferably, preferred or more preferred utilized in the description above indicate that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the invention, the scope being defined by the claims that follow.
[0051] In reading the claims, it is intended that when words such as “a,” “an,” “at least one,” or “at least one portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. When the language “at least a portion” and/or “a portion” is used the item can include a portion and/or the entire item unless specifically stated to the contrary.
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Systems and methods are disclosed for controlling access devices including WI-FI and dual radio communications between an access control database and one or more access devices in a facility. The systems and methods allow real time communications between the database and the access devices utilizing existing communications WI-FI infrastructure in the facility while minimizing loss of battery life of the access devices by employing the radio network to target all or a portion of the access devices for communications when needed.
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BACKGROUND OF THE INVENTION
In the usual saccharification of starch, starch is once cooked to gelatinize, this gelatinized starch is liquefied by the action of α-amylase and, thereafter, glucoamylase is added to produce dextrose. This method, however, requires a large amount of energy for gelatinizing the starch prior to its saccharification. In order to minimize such energy consumption, extensive researches have been made particularly in recent years for amylase which can be applied directly to raw starch, that is, is capable of hydrolyzing directly the raw starch.
Such energy-saving starch saccharification is essential for the production of alcohol fuel from various starches as biomass sources. In connection with the alcoholic fermentation of raw starch, investigations by S. Ueda et al., Hayashida et al., Y. K. Park et al., and so on are known. S. Ueda et al. have long studied the alcoholic fermentation of raw starch using glucoamylase produced by Black Aspergillus, Asp. awamori (see S. Ueda & Y. Koba, J. Fermentation Technology, 58, No. 3, 237 (1980), and S. Ueda et al., Biotech. Bioeng., Vol. 23, 291 (1981)). Hayashida et al. report that amylase produced by Asp. awamori is more effective in the hydrolysis of raw starch than amylase produced by Asp. oryzae or malt amylase. Y. K. Park et al. report the studies on the alcohol fermentation of starch without gelatinizing starch, using glucoamylase produced by Aspergillus niger or Aspergillus awamori (see Biotech. Bioeng., 24, 495 (1982).
In the saccharification of raw starch using glucoamylases produced by Aspergillus niger, Aspergillus awamori, or fungus belonging to genus Rhizopus, some problems still remain unsolved. The most serious problem is that the rate of hydrolysis of raw starch of the above-described enzymes are seriously low compared with their rate of hydrolysis of gelatinized starch. In other words, their raw starch-hydrolyzing activity is seriously low although they have high enzymatic activity. Usually it is considered that enzymes capable of hydrolyzing raw starch at a rate of hydrolysis of about 1/30 of that for gelatinized starch are promising as raw starch-hydrolyzing enzymes (see S. Ueda, Workshop, Carbohydrate Sources and Biotechnology, page 25 (1982), held under the auspices of National Food Research Institute, Japan and sponsored by The United Nations University).
About 2,000 strains of microorganisms living in soil and on wood were isolated by us and examined to find those microorganisms satisfying the requirement that the ratio of the gelatinized starch-hydrolyzing degree to the raw starch-hydrolyzing degree is 10:1 or less. It has been found that some microorganisms satisfy the foregoing requirement. They are strains belonging to genus Chalara, and the properties of the enzymes secreted by them are similar to those of glucoamylases in respect of the mechanisms of enzyme reactions. These enzymes are active and stable in a slightly acidic region and have greatly higher raw starch-hydrolyzing activity compared with conventional glucoamylases; that is, the ratio of the gelatinized starch-hydrolyzing activity to the raw starch-hydrolyzing activity is from 3.5:1 to 5:1, which is greatly higher compared with those of the known glucoamylases. Hence it has been found that the saccharification of raw starch can be performed advantageously on a commercial scale by using the above-described enzymes.
SUMMARY OF THE INVENTION
The present invention relates to a process for the saccharification of starch (raw or gelatinized), characterized by saccharifying a starch by the use of an amylase produced by a fungus belonging to genus Chalara to produce dextrose directly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a curve showing activities at different pH values of a crude enzyme produced by Chalara paradoxa PNS-80 of the invention, said activity being indicated as relative value of raw starch-hydrolyzing activity to gelatinized starch-hydrolyzing activity; said activities are determined by incubating said enzyme with corn starch (raw starch) at 30° C. for 30 minutes or by incubating said enzyme with soluble starch (gelatinized starch) at 40° C. for 30 minutes. It discloses that activity is present over the range of pH of from about 3.5 to 9.5 and good results are obtained up to a pH of about 7, with best results obtained from about 3.5 to 6.
FIG. 2 is a pH stability curve (over the range of 3-9.5) as determined by measuring the residual activity of an enzyme solution after its treatment at 40° C. for 30 minutes, provided that the measurement conditions are the same as in FIG. 1.
FIG. 3 is a curve showing the optimum temperature of the present enzyme produced by Chalara paradoxa PNS-80, which is obtained by plotting relative enzyme activities as determined by incubating said enzyme with starch at a predetermined temperature for 30 minutes. It further discloses a broad temperature range when using raw starch of about 30° to 50° C. and that best results for raw starch are obtained at temperatures of about 40° to 48° C.
FIG. 4 shows temperature stability of the present enzyme produced by Chalara paradoxa PNS-80, and it is obtained by plotting the residual activity of an enzyme solution after its treatment at a predetermined temperature for 30 minutes.
FIG. 5 is a raw corn starch-hydrolyzing curve as determined under the conditions described in Example 7.
DETAILED DESCRIPTION OF THE INVENTION
Any fungi belonging to genus Chalara and having an ability to produce enzyme of high raw starch-hydrolyzing ability can be used in the invention. A typical example is a strain Chalara paradoxa PNS-80. Its microbiological characteristics as determined based on K. Tsubaki and S. Udagawa, A PICTURE BOOK OF FUNGI (last volume), Kodansha Life Scientific Publishers are as follows:
(I) Morphological Characteristics
(a) It forms conidiophores growing vertically from hyphae, which have a long cylindrical form and 2 to 3 septa.
(b) It forms phialo type conidia which are cylindrical or barrel-like in shape and have an average size of 12 microns×4 microns.
(c) It forms brown or gray-black thick wall spores, the skin layer of which is covered with a smooth or irregular external wall.
(II) Culture Characteristics
(a) It grows on a malt agar medium in the form of gray or gray-yellow flocculence. At a later stage of the growth, it further becomes dark.
(b) It grows on a medium comprising 1% soluble starch, 1% polypeptone, and 0.7% bouillon in the same flocculent form as in (a) above.
In view of the above-described morphological and culture characteristics, it is reasonable to identify the strain as Chalara paradoxa. This strain has been deposited in the Fermentation Research Institute under the accession number of FERM BP-422.
The desired enzymes can be prepared by cultivating the fungus belonging to genus Chalara by the usual aerobic liquid cultivation or cultivation aerated with agitation. For this purpose, various culture media can be used. As a carbon source, raw starch from corn, potato, sweet potato, tapioca, waxy corn, rice, wheat, sago, high-amylose corn and so forth, and a starch hydrolyzate of DE 10-25 are preferred to use in a proportion of from 2 to 7%, since the desired enzymes are induced using raw starch. As a nitrogen source, peptone, meat extract, corn steep liquor, peptide-containing compounds, and so forth can be used singly or in combination with each other. If desired, small amounts of inorganic salts, such as NaCl, FeSO 4 , Ba(OH) 2 , FeCl 3 .6H 2 O, SrCl 2 .6H 2 O, LiCl, MgSO 4 .7H 2 O, and MnSO 4 .5H 2 O, can be added.
The thus-prepared culture medium is inoculated with the above-described strain, which is then cultivated under aerobic conditions at pH 4-8.5 at 25°-40° C. for 24-96 hours, whereby the desired enzyme can be accumulated therein.
The enzyme used in the present process may be utilized when still part of the culture broth obtained by cultivating the amylase-producing microorganism belonging to genus Chalara on a nutrient medium in the manner described above, in the form of its filtrate, in the form of a concentrated filtrate, and in the form of a purified enzyme prepared from the filtrate.
Separation and purification of the present enzyme can be performed by the known procedures which have been widely used in the separation and purification of enzymes from their culture broth. For example, a method of concentrating the filtrate under reduced pressure or by ultrafiltration, a method of salting out with compounds such as ammonium sulfate, sodium sulfate and sodium chloride, a specific adsorption method utilizing raw starch, a fractional precipitation method using compounds such as methanol, ethanol and acetone, a chromatographic method using DEAE-Sephadex and an ion exchange resin, an isoelectric point precipitation method, and an electric dialysis method can be used singly or in combination with each other.
The activity of the enzyme is measured as follows:
A mixture of 20 milligrams of raw corn starch, 0.2 milliliter of a 0.1 M acetate buffer (pH: 4.5), 0.2 milliliter of an enzyme solution, and 1.6 milliliters of deionized water is incubated at 40° C. for 30 minutes. At the end of the time, the amount of glucose formed is measured by the Somogyi-Nelson method. One unit of enzyme activity is defined as the amount of enzyme which produces 1 micromole (180 micrograms) of glucose per minute under the conditions as described above.
The gelatinized starch-hydrolyzing activity is determined by measuring the amount of reducing sugar formed when the same experiment as above is performed using 0.25 milliliter of a 2% soluble starch solution. One unit of the activity is defined in the same manner as above.
The physical and chemical properties of the present enzyme are shown below. This enzyme is the one isolated by ultra filtration of the culture filtrate.
(1) Action and Substrate Specificity
The present enzyme is capable of hydrolyzing raw and gelatinized starches from corn, potato, rice, sweet potato, waxy corn, sago and tapioca, yielding reducing sugar. Paper chromatography and high-pressure liquid chromatography analyses of the reducing sugar show that oligosaccharides including disaccharide are not formed and glucose is formed and accumulated from the initial stage of the reaction. It is believed, therefore, that the present enzyme is a glucoamylase which converts starch into glucose by an exo-type reaction.
(2) Optimum pH and Stable pH Range
The optimum pH and stable pH range were determined by applying a 0.2 M acetate buffer (pH: 3-5.0), a trismalate buffer (pH: 5.5-8.5), and a sodium carbonate buffer (pH: 9.0-10.0) to raw starch at 40° C. for 30 minutes. The results are shown in FIGS. 1 and 2.
(3) Optimum Temperature and Temperature Stability
The optimum temperature was determined by measuring the fomed reducing sugar after 30 minutes incubation with soluble starch solution, and temperature stability were determined by the remaining enzyme activity after its treatment for 30 minutes at different temperatures. Experimental results obtained using gelatinized soluble starch as a substrate are shown in FIGS. 3 and 4. Since the present enzyme is intended to apply to raw starch, it is used within the stable temperature range thereof.
(4) Influences of Coexisting Ions
Addition of calcium (Ca) ion increases the thermal stability of the gelatinized starch-hydrolyzing activity by about 5° C.
Glucose can be formed by application of the present enzyme to raw starch and/or gelatinized starch.
Strains capable of producing the present enzyme include, as well as Chalara paradoxa PNS-80, Chalara fusidioides, Chalara cylindrosperma, Chalara mycoderma, Chalara quercina and Chalara elegans.
The present invention permits the direct saccharification of starch and, therefore, it provides a process for producing conveniently and efficiently useful substances such as alcohols from various starches such as biomass sources. In particular, the enzyme of the invention is suitable for industrial utilization because of its high raw starch-hydrolyzing activity.
The following Examples are for illustrative purposes only and are not meant to limit the invention set forth in the claims appended hereto.
EXAMPLE 1
One liter of a medium containing 65 grams of corn steep liquor, 7 grams of meat extract, 3 grams of sodium chloride, and 500 milligrams of ferrous sulfate (adjusted to pH 4.0) was placed in a 5-liter flask and sterilized. After sterilization, 40 grams of sago starch which had been subjected to dry air sterilization at 100° C. was added to the medium, which was then inoculated with one loop of slant culture of Chalara paradoxa PNS-80 (FERM BP-422). Shaking cultivation was performed at 30° C. for 5 days.
After the cultivation was completed, microorganisms and unreacted starch were removed by centrifugal separation, and a supernatant was used as a crude enzyme solution (raw starch-hydrolyzing activity: 1.0 International Unit (IU) per milliliter).
Granules, i.e. raw, waxy corn starch, corn starch, and wheat starch were placed in the respective Erlenmeyer flasks each in an amount of 2.5 grams. Then 25 milliliters of the enzyme solution as prepared above was added to each flask. Furthermore 25 milliliters of a 0.1 M acetate buffer (pH 4.5) and 200 milliliters of deionized water were added, and shaking cultivation was performed at 30° C.
The amount of glucose formed was measured by the Somogyi-Nelson method. The degree of hydrolysis of each starch after 24 hour reaction was as follows:
Corn starch: 68%
Waxy corn starch: 85.5%
Wheat starch: 76.3%
Paper chromatography analysis shows that the sugar formed consisted of dextrose alone.
EXAMPLE 2
The same strain as used in Example 1 was cultivated on a medium consisting of 65 grams of corn steep liquor, 3 grams of sodium chloride, and 70 grams of tapioca which had been sterilized with radiation. After the cultivation was completed, 2 volumes of ethanol was added to one volume of the fermentation broth to precipitate an enzyme. To 50 milligrams of the precipitate were added 50 milliliters of a 0.1 M acetate buffer (pH 4.5) and 200 milliliters of deionized water.
Thereafter rice starch, potato starch, and sweet potato starch were hydrolyzed in the same manner as in Example 1. The degree of hydrolysis of each starch after 24 hour reaction was as follows:
Rice starch: 89%
Potato starch: 11%
Sweet potato starch: 48.6%
EXAMPLE 3
One liter of a medium containing 65 grams of corn steep liquor, 7 grams of meat extract, 3 grams of sodium chloride, and 500 milligrams of ferrous sulfate (adjusted to pH 4.0) was placed in a 5-liter Erlenmeyer flask and sterilized. After the completion of sterilization, 70 grams of sago starch which had been sterilized with γ-ray radiation was added to the medium, which was then inoculated with one loop of slunt culture of the same strain as used in Example 1. Shaking cultivation was performed with shaking for 6 days.
After the cultivation was completed, the fermentation broth was subjected to centrifugal separation to obtain a supernatant. This supernatant was used as a crude enzyme solution (1.6 International Units per milliliters (IU/ml)) in the raw starch-hydrolyzing reaction as described below.
Rice starch, waxy corn starch, and wheat starch were placed in the respective Erlenmeyer flasks each in an amount of 5 grams. Then 25 milliliters of the enzyme solution as prepared above, 25 milliliters of a 0.1 M acetate buffer (pH 4.5), and 200 milliliters of deionized water were added to each flask. Shaking cultivation was performed at 30° C. for 48 hours.
The amount of glucose formed was measured by the Somogyi-Nelson method. The degree of hydrolysis of each starch was as follows:
Rice starch: 86%
Waxy corn starch: 86%
Wheat starch: 86%.
EXAMPLE 4
The procedure of Example 3 was repeated wherein tapioca starch and sweet potato starch were used as the substrate in place of the rice starch, waxy corn starch, and wheat starch.
The degree of hydrolysis of each starch was as follows:
Tapioca starch: 89.8%
Sweet potato starch: 84%
EXAMPLE 5
The procedure of Example 3 was repeated wherein sago starch and potato starch were used as the substrate in place of the rice starch, waxy corn starch, and wheat starch.
The degree of hydrolysis of each starch was as follows:
Sago starch: 52%
Potato starch: 35%.
EXAMPLE 6
One liter of a medium containing 65 grams of corn steep liquor, 7 grams of meat extract, 3 grams of sodium chloride, and 300 milligrams of ferrous sulfate (adjusted to pH 4.0) and placed in a 5-liter flask and sterilized. After sterilization, 70 grams of sago starch which had been sterilized with radiation was added to the medium, which was then inoculated with one loop of slunt culture of the same strain as used in Example 1. Shaking cultivation was performed for 5 days. Microorganisms were removed by centrifugal separation, and a supernatant was used as a crude enzyme solution (activity for gelatinized starch: 14.9 International Units per milliliter (IU/ml); activity for raw starch: 1.6 International Units per milliliter (IU/ml)).
A mixture of 2.5 grams of each of the raw starches as described in the Table, 12.5 milliliters of a 0.1 M acetate buffer (pH 4.0), 100 milliliters of deionized water, and 12.5 milliliters of the crude enzyme solution as prepared above was incubated at 30° C. After 24 hours and 48 hours, the degree of hydrolysis of the starch was measured. The results are shown in the Table below.
TABLE______________________________________ TimeStarch 24 hours 48 hours______________________________________Rice starch 95.0 96.1Waxy corn starch 93.5 97.3Wheat starch 91.5 96.2Corn starch 90.9 95.6Tapioca 81.2 99.8Sweet potato starch 73.3 92.6Sago starch 33.5 57.7Potato starch 19.4 38.6______________________________________
EXAMPLE 7
A mixture of 42 milliliters of an enzyme solution as prepared in Example 6 (raw starch-hydrolyzing activity: 66 International Units in 40 milliliters (IU/ml)), 20 milliliters of a 0.1 M acetate buffer, and 38 milliliters of deionized water was prepared in a 500-milliliter flask. To this enzyme solution was added raw corn starch in an amount of 10 grams, 20 grams or 30 grams. The degree of hydrolysis at each amount was measured and plotted to obtain a hydrolysis curve as shown in FIG. 5. When the amount of the starch added was 10 grams, the degree of hydrolysis after 7 day incubation was 100%; when the amount of the starch added was 20 grams, the degree of hydrolysis after 9 day incubation was 90%; and when the amount of the starch added was 30 grams, the degree of hydrolysis after 9 day incubation was 72%.
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A process for the saccharification of starch, which comprises saccharifying a raw and/or gelatinized starch by the use of an amylase produced by a fungus belonging to genus Chalara to produce glucose.
According to the process of the present invention, the starch is directly saccharified, and glucose can be obtained efficiently.
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BACKGROUND OF THE INVENTION
This invention relates to an improved hand held gauge utilized for measuring the degree of alignment of the inner surfaces of two tubular members positioned end to end and further for measuring wall thickness of a tubular member.
SUMMARY OF THE INVENTION
The gauge includes parallel first and second bar members having mutually contacting side faces which extend longitudinally of the bar members. The bar members are shiftable lengthwise or longitudinally relative to each other and have corresponding juxtaposed end parts which are each defined by a laterally projecting contact. These contacts project oppositely of one another in the same plane and each includes an edge face disposed at a substantially right angle to the longitudinal dimension of its bar member. A shouldered retainer part is carried by the bar members. The shouldered retainer part is shiftable along the bar members toward and away from the contact: edge faces.
Reference may be had to Patent having U.S. Pat. No. 4,165,566 for a further detailed description. The novelty of this gauge rests in the unique shouldered retainer part and the use of associated indicia on the bars which are readable through the shouldered retainer part. The shouldered retainer part extends around the bar members and has side walls located on opposite sides of the gauge. Each side wall of the retainer part has an oval shaped window. A standard or English scale is imprinted on one side face of the bar members so that the scale may be observed through one window of the overlying retainer part as the retainer part is moved along the bar members. Similarly, a metric scale is imprinted on the opposite face of the bar members so that the scale may be observed through the other window of the overlying retainer part.
Accordingly, it is an object of this invention to provide a manually operable, hand held gauge for measuring and documenting in either English or metric at that the same setting the degree of mis-alignment at the inner surfaces of two tubular members positioned end to end.
Another object of this invention is to provide a multi-purpose measuring gauge having an English and metric scale for use in determining the thickness, inner surface alignment and shoulder lengths of tubular members placed end to end.
Other objects of this invention will become apparent upon a reading of the invention's description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the gauge from one side.
FIG. 2 is a perspective view of the gauge from the opposite side.
FIG. 3 is a perspective view of the gauge showing the parts thereof in exploded form.
FIG. 4 is a plan view of the gauge being utilized to measure the alignment of abutting pipes.
FIG. 5 is a sectional view of the pipes seen in FIG. 4 showing the gauge in operative position and with portions of the gauge parts broken away for purpose of illustration.
FIG. 6 is a perspective view of the gauge showing a modification to the foot part of each of the gauge's bar members.
FIG. 7 is a sectional view of the pipes showing the gauge of FIG. 6 in operative position measuring the offset of the pipes over a protruding weld.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment illustrated is not intended to be exhaustive or to limit the invention to the precise form disclosed, It is chosen and described in order to best explain the principles of the invention and its application and practical use to thereby enable others skilled in the art to best utilize the invention.
Gauge 10 as shown in the figures includes two bar members 12 and 13, a shoulder retainer part 14 and a tightening screw 16. Each bar member 12 and 13 includes end parts 18 and 20 and oppositely positioned parallel inner side face 22 and outer side face 24 which extend between the end parts along the longitudinal dimension of the bar member. The end part 18 of each bar member 12 and 13 is formed into a contact 26 which projects laterally outwardly from the adjacent side face 24 of the bar member. The opposite end part 20 of each bar member 12 and 13 is formed into a right angular foot part 28 which also projects laterally outwardly from side face 24 of the bar member.
The bar members are placed side by side in mutual contact at side faces 22. Shoulder retainer part 14 is enclosed around bar members 12 and 13 and is fitted against bar member 13 therein. The shoulder retainer part includes a contact surface 32 which extends at a right angular relationship to side face 24 of bar member 13. Tightening screw 16 includes a threaded shank 34 which extends with clearance from edge wall 25 of the shoulder retainer part 14. The screw shank 34 is turned into threaded opening 27 of edge wail 25 of the shoulder retainer part and bears against outer edge 24 of bar member 13.
As explained in U.S. Pat. No. 4,165,566, incorporated herein by reference, bar member 12, 13 slide relative to each other and to retainer part 14. Retainer part 14 includes side walls 35, 37. Side walls 35, 37 each have an oval shaped window 39 and 41 formed therein. Another threaded screw 61 is turned into a threaded opening 63 in retainer part edge wall 25 and lightly against bar member 13 to urge the bar members against each other.
Each contact 26 of bar members 12 and 13 includes an edge face 38 which extends at a right angle to side face 24 of the associated bar member. Contact edge face 38 of bar member 13 parallels contact surface 32 of shoulder retainer part 14 with the shoulder retainer part being shiftable longitudinally along the bar member in an oppositely spaced relationship from the contact edge face. Details about the function and operation of the retainer part 14 and tightening screw 16 is described in U.S. Pat. No. 4,165,566.
The operation of the gauge will now be described. In FIGS. 4 and 5, two end to end positioned tubular members or pipes 48 are shown. Each pipe 48 includes an outer surface 50, an inner surface 52 and a beveled end edge 54. End edges 54 of the pipes are located in close proximity, though not touching, and are beveled so as to form in conjunction with one another a groove 55 to accommodate welding of the pipes together. In certain constructions, such as in the construction of a nuclear reactor, the inner surfaces 52 of pipes 48 must be aligned within a close tolerance in order that when the weld is subjected to radiography there will be no drastic density change due to misalignment. Gauge 10 is designed to measure this inner surface pipe alignment. Contacts 26 are of a thin construction and are connected to the body of the bar members 12 and 13 by narrow neck part 56 to enable the contacts to be first inserted edgewise in the spacing between pipe edges 54 and the gauge then turned so that edge face 38 of each contact overlies a pipe inner surface 52 as seen in FIG. 4.
Tightening screw 16 is loosened to permit shifting of the bar members to bring contact edge faces 38 into intimate contact with the respective inner surfaces of pipes 48, while shoulder retainer part 14 can be slid toward the pipes with its contact surface 32 being brought into engagement with the outer surface 50 of one of the pipes. The engagement of shoulder retainer part 14 with one of the pipes squares the gauge relative to at least one of the pipes and ensures a more accurate determination of the degree of alignment of the two pipes. After contact surface 32 of shoulder retainer part 14 and contact edge faces 38 of the bar members are brought into engagement with pipes 48 as shown in FIG. 4 screw 16 may be tightened, locking the bar members and shoulder retainer part together as a unit. The degree of alignment can then be directly read by observing the offset, if any, of either scale 44 or scale 47 depending upon whether the reading is to be in standard or metric terms. Reduced neck parts 56 of contacts 26 will permit the gauge to be turned, causing the contacts to be aligned with the opening between beveled end edges 54 of the pipes, to permit the gauge to be removed with the bar members and shoulder retainer part remaining locked together.
To measure the pipe wall thickness, a user would loosen tightening screw 16 to allow the shoulder retainer part 14 to move. Then, contact 26 of bar member 13 is placed against the inner surface 52 of the pipe as one would do if measuring the degree of alignment of the inner surfaces of the two tubular members positioned end to end. The shoulder retainer part 14 is slid against the pipe's outer surface 50. The screw is tightened and the gauge is removed. The pipe wall thickness is read through either of the windows 39, 41 with the wall thickness being observed on either scale 49 or scale 51 (depending upon whether the reading is to be in standard or metric terms) at indicator 65 protruding from the edge of each window.
In an alternative embodiment as illustrated in FIG. 6 and FIG. 7, gauge 60 illustrated in the drawings includes bar members 62 and 64, which are retained in a parallel relationship with mutually contacting side faces by a shouldered retainer part 66. Each bar member 62, 64 has one end formed into a contact 68, and its opposite end formed into a right angular foot 82. Retainer part 16 also encloses bar members 62, 64 with each bar member being shiftable relative to the other and to the retainer part. A screw member 70 is threaded into retainer part 66 and serves to secure the bar members in place when a measurement is taken.
An English or standard scale 72 also is imprinted upon face 73 of each bar member. Scales 72 are precisely aligned when contact edge faces 78 of the bar members lie within the same plane. Any offset of edge faces 78 as illustrated in FIGS. 6 and 7 will cause the misalignment of scales 72 which indicates to the user of the gauge 60 the amount of such offset. Additionally, a separate set of scales 80 extend along foot parts 82 of the bar members upon faces 73 to permit the measurement across shoulders of adjoining piping or similar tubular members with the bar members being offset to accommodate the offset of the shoulders. A metric scale (not shown) is imprinted upon the opposite face 83 of each bar member. Also, a separate set of metric scales 86 extend along foot parts 82 of the bar members upon faces 83.
Another English or standard scale 88 is also imprinted on face 73 of bar member 64 and is observable through window 90 of shoulder retainer part 66. A metric scale (not shown) is imprinted on the face 83 of bar member 64 and is observable through the opposite window. The scales are used to measure the distance between edge face 78 of bar member 64 and surface 96 of retainer part 66. The manner of operation of gauge 10 as thus far described is similar to the previous embodiment with the exception of the improvement discussed below.
This embodiment involves the forming of notches 100, 102 along the contact surfaces or soles 81 of feet 82 at the inner contacting faces of bar members 62, 64. Constructed in this fashion, gauge 60 may be used to measure the alignment of two tubular members 103 after a weld 104 from either a consumable Ping or an open butt has been applied to join the tubular members.
To utilize gauge 60 in this fashion, feet 82 are positioned so that notches 100, 102 span and overlie the root or protrusion weld 104 between tubular members 103. Feet 82 may be so positioned at the inside surface 106 of tubular members 103, as shown in FIG. 7, or on the outside surface 108 of the tubular members. The amount of offset of tubular members 103 may then be determined by reading scale 72 of gauge 60.
It is to be understood that the invention is not to be limited to the details above given but may be modified within the scope of the appended claims.
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A metric and English measuring gauge including parallel first and second bar members having mutually engaging side faces and including contact end portions for engagement with tubular members wherein the offset of such tubular members will be indicated by the relative longitudinal position of the bar members. A shoulder retaining part is enclosed around the bar members and has windows on opposite sides for observing metric and English scales imprinted un opposite sides of the bar members for measuring wall thickness.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 10/770,448, filed Feb. 4, 2004 and titled “Dynamic Rendering of Ink Strokes with Transparency,” now U.S. Pat. No. 7,091,963, which application is a continuation of U.S. patent application Ser. No. 09/918,484, filed Aug. 1, 2001 and titled “Dynamic Rendering of Ink Strokes with Transparency,” now U.S. Pat. No. 6,707,473. This application is related to U.S. patent application Ser. No. 10/972,391, entitled “Dynamic Rendering of Ink Strokes with Transparency,” filed Oct. 26, 2004, U.S. patent application Ser. No. 09/918,721, entitled “Rendering Ink Strokes of Variable Width and Angle,” filed Aug. 1, 2001, and U.S. patent application Ser. No. 09/852,799, entitled “Serial Storage of Ink and its Properties,” filed May 11, 2001. All of said applications are hereby incorporated by reference as to their entireties.
FIELD OF THE INVENTION
The present invention is directed generally to rendering transparent digital ink, and more particularly to improved ways of rendering transparent digital ink dynamically.
BACKGROUND OF THE INVENTION
The term “digital ink” refers to one or more strokes that are recorded from a pointing device, such as a mouse, a stylus/pen on a digitizer tablet, or a stylus/pen on a display screen integrated with a digitizer tablet (e.g., a touch-sensitive display screen). As used herein, the term “ink” is shorthand for digital ink. Also, the term “pen” and “stylus” are used generically and interchangeably. Each stroke may be stored as one or more ink packets, in which each ink packet may contain coordinates (x, y) corresponding to the position of the pointing device. For example, a user may move a pen along a touch-sensitive display screen of a computer system so as to draw a line or curve, and the computer system may sample the coordinates (x, y) along the trajectory of the pen tip position over time (or on any other interval as known in the art) as the user moves the pen. These coordinates represent points along the curve or line and are stored as ink packets.
Ink may be either transparent or non-transparent, as used herein. Ink that is transparent means that the ink does not fully conceal the background behind it when displayed on a display or printed on a printer. Ink that is not transparent completely conceals or occludes the background behind it. Non-transparent ink may also be referred to as opaque ink. For instance, FIG. 1 shows ink strokes 101 , 102 , and 103 . Ink strokes 102 and 103 each overlay ink stroke 101 , but ink stroke 103 completely conceals its background, including the portion of ink stroke 101 that it overlays (i.e., the portion of ink stroke 101 that is a background behind ink stroke 103 ). Thus, ink stroke 103 is considered opaque. In contrast, ink stroke 102 allows some of ink stroke 101 , as well as some of the white background, to show through where ink stroke 102 overlays ink stroke 101 . Thus, ink stroke 102 is considered transparent. Ink can be of any transparency and still be considered transparent. Current graphics interfaces are capable of applying transparent paint with a prescribed degree of transparency. For example, ink may be 50% transparent, which means that 50% of the background is concealed, or ink may be 25% transparent, which means that 75% of the background is concealed. A transparent ink stroke can be analogized with a piece of glass, such as colored glass, in which objects behind the glass can be seen. A non-transparent ink stroke can be analogized with a brick wall that hides everything behind it.
It is often desirable to render a transparent ink stroke dynamically while the ink stroke is being drawn, in other words, to draw the ink stroke on the display screen while the pointing device moves and adds new points to the ink stroke or strokes. One way to accomplish this is to erase the entire screen and redraw everything on the screen each time a new point is added to the ink stroke. This is an imperfect solution, however, since in practice there is typically a short time interval between ink points, and repeatedly clearing and redrawing the screen uses massive amounts of processing power, not to mention causing the screen to flicker. A way to reduce the redrawing time would be draw each new segment of an ink stroke as it is drawn. The problem with this is that the transparencies of the overlapping portion of ink segments are reduced in an unexpected and unintended manner. The effect of redrawing transparent ink is shown in FIG. 2 , where the darker circles of an ink stroke 200 represent the overlapping start and end points of the segments. These overlapping areas are darker because they are each drawn twice—once when a segment ending with a particular point is drawn, and again when the next segment beginning with the same point is drawn—thereby reducing the transparency at the overlap. The result is an unintentionally non-uniform ink stroke. This is analogous to repeatedly making a glass window thicker, thereby making objects on the other side of the glass more difficult to see by making the window darker. The variable transparency of the rendered ink is unexpected to the user who would expect transparent ink to be rendered as transparent physical ink as applied to paper and/or over other ink.
There is also a need for providing various artistic features not provided by current systems, such as dynamically rendering ink responsive to variable width, pressure, speed, and angle of the pen.
SUMMARY OF THE INVENTION
Apparatus and methods are disclosed for dynamically rendering transparent ink strokes that solves at least one of the problems associated with rendering transparent ink. Using the present invention, the rendering of electronic ink (or ink as used herein) is improved. For example, the ink stroke may be dynamically rendered as a stroke having uniform transparency while it is being drawn. This may be performed without having to clear and redraw the entire screen.
To dynamically draw a transparent ink stroke, a computer system may draw only the segment that has most recently been added to the stroke. The system may further exclude areas of the new segment that overlap older portions of the stroke from being painted more than once, which would otherwise make the older segments less transparent. For instance, the color settings of pixels in the overlapping areas may be frozen before painting the new segment. Freezing the color settings may reduce or prevent unintended non-uniformities in the ink stroke.
These and other features of the invention will be apparent upon consideration of the following detailed description of preferred embodiments. It will be apparent to those skilled in the relevant technology, in light of the present specification, that alternate combinations of aspects of the invention, either alone or in combination with one or more elements or steps defined herein, may be used as modifications or alterations of the invention or as part of the invention. It is intended that the written description of the invention contained herein covers all such modifications and alterations.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary of the invention, as well as the following detailed description of preferred embodiments, is better understood when read in conjunction with the accompanying drawings, which are included by way of example, and not by way of limitation with regard to the claimed invention. In the accompanying drawings, elements are labeled with reference numbers, wherein the first digit of a three-digit reference number, and the first two digits of a four-digit reference number, indicates the drawing number in which the element is first illustrated. The same reference number in different drawings refers to the same or a similar element.
FIG. 1 is an exemplary embodiment of both transparent and non-transparent digital ink as they may be displayed, according to at least one aspect of the present invention.
FIG. 2 is an exemplary embodiment of transparent digital ink as it may be displayed, showing non-uniformities due to blending of multiple segments.
FIG. 3 is an exemplary embodiment of transparent digital ink as it may be displayed, without the non-uniformities of the ink shown in FIG. 2 , and according to at least one aspect of the present invention.
FIG. 4 is a functional block diagram of an exemplary embodiment of a computer system according to at least one aspect of the present invention.
FIG. 5 is a functional block diagram of an exemplary embodiment of an ink rendering system according to at least one aspect of the present invention.
FIG. 6 is an exemplary flowchart showing steps that may be performed in order to render transparent ink according to at least one aspect of the present invention.
FIG. 7 is an exemplary geometrical representation of stroke segments including circular pen tip instances and connecting quadrangles according to at least one aspect of the present invention.
FIG. 8 is an exemplary embodiment of digital ink corresponding to the stroke segments of FIG. 7 as it may be displayed, according to at least one aspect of the present invention.
FIG. 9 is an exemplary geometrical representation of a frozen region within a series of stroke segments, according to at least one aspect of the present invention.
FIG. 10 is a functional block diagram of an exemplary embodiment of another ink rendering system according to at least one aspect of the present invention.
FIG. 11 is an exemplary geometrical representation of a stroke including differently-sized circular pen tip instances and connecting quadrangles according to at least one aspect of the present invention.
FIG. 12 is an exemplary embodiment of digital ink corresponding to the stroke of FIG. 11 as it may be displayed, according to at least one aspect of the present invention.
FIG. 13 is an exemplary geometrical representation of a stroke including differently-sized and differently-angled oval pen tip instances and a connecting quadrangle according to at least one aspect of the present invention.
FIG. 14 is an exemplary embodiment of digital ink corresponding to the stroke of FIG. 13 as it may be displayed, according to at least one aspect of the present invention.
FIG. 15 is an exemplary geometrical representation of a stroke including differently-sized and differently-angled rectangular pen tip instances and a connecting quadrangle according to at least one aspect of the present invention.
FIG. 16 is an exemplary embodiment of digital ink corresponding to the stroke of FIG. 15 as it may be displayed, according to at least one aspect of the present invention.
FIGS. 17A and 17B are exemplary geometrical representations of a stroke including differently-sized and differently-angled rectangular pen tip instances and two different possible connecting quadrangles according to at least one aspect of the present invention.
FIG. 17C is an exemplary representation of the stroke of FIGS. 17A and 17B including all of the possible corner-connecting quadrangles according to at least one aspect of the present invention.
FIG. 18 is an exemplary embodiment of digital ink corresponding to the stroke of FIG. 17C as it may be displayed, including all possible connecting quadrangles, according to at least one aspect of the present invention.
FIG. 19 is a functional block diagram of an exemplary embodiment of yet another ink rendering system according to at least one aspect of the present invention.
FIG. 20 is a geometric representation of an exemplary ink stroke illustrating the sample points therein as well as a fitting curve for position, width, and rotation, in accordance with at least one aspect of the present invention.
FIG. 21 is a representation of a rendered exemplary ink stroke according to at least one aspect of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Improved transparent ink rendering systems and methods are disclosed. The various embodiments of the invention are described in the following sections: General Purpose Computing Environment, Ink Rendering System, and Ink Smoothing.
General Purpose Computing Environment
FIG. 4 illustrates a schematic diagram of an exemplary general-purpose digital computing environment that may be used to implement various aspects of the present invention. In FIG. 4 , a computer 400 such as a personal computer includes a processing unit 410 , a system memory 420 , and/or a system bus 430 that couples various system components including the system memory to processing unit 410 . System bus 430 may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. System memory 420 includes read only memory (ROM) 440 and random access memory (RAM) 450 .
A basic input/output system 460 (BIOS), containing the basic routines that help to transfer information between elements within computer 400 , such as during start-up, is stored in ROM 140 . The computer 400 also includes a hard disk drive 470 for reading from and writing to a hard disk (not shown), a magnetic disk drive 480 for reading from or writing to a removable magnetic disk 490 , and an optical disk drive 491 for reading from or writing to a removable optical disk 492 such as a CD ROM or other optical media. Hard disk drive 470 , magnetic disk drive 480 , and optical disk drive 491 are connected to the system bus 430 by a hard disk drive interface 492 , a magnetic disk drive interface 493 , and an optical disk drive interface 494 , respectively. The drives and their associated computer-readable media provide nonvolatile storage of computer readable instructions, data structures, program modules and other data for personal computer 400 . It will be appreciated by those skilled in the art that other types of computer readable media that can store data that is accessible by a computer, such as magnetic cassettes, flash memory cards, digital video disks, Bernoulli cartridges, random access memories (RAMs), read only memories (ROMs), and the like, may also be used in the example operating environment.
A number of program modules can be stored on hard disk drive 470 , magnetic disk 490 , optical disk 492 , ROM 440 , and/or RAM 450 , including an operating system 495 , one or more application programs 496 , other program modules 497 , and program data 498 . A user can enter commands and information into computer 400 through input devices such as a keyboard 401 and pointing device 402 . Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner or the like. These and other input devices are often connected to processing unit 410 through a serial port interface 406 that is coupled to the system bus, but may be connected by other interfaces, such as a parallel port, game port or a universal serial bus (USB). Further still, these devices may be coupled directly to system bus 430 via an appropriate interface (not shown). A monitor 407 or other type of display device is also connected to system bus 430 via an interface, such as a video adapter 408 . In addition to the monitor, personal computers typically include other peripheral output devices (not shown), such as speakers and printers. In one embodiment, a pen digitizer 465 and accompanying pen or stylus 466 are provided in order to digitally capture freehand input. Although a direct connection between pen digitizer 465 and processing unit 410 is shown, in practice, pen digitizer 465 may be coupled to processing unit 410 via a serial port, parallel port, and/or other interface and system bus 430 as known in the art. Furthermore, although digitizer 465 is shown apart from monitor 407 , in some embodiments the usable input area of digitizer 465 be co-extensive with the display area of monitor 407 . Further still, digitizer 465 may be integrated in monitor 407 , or may exist as a separate device overlaying or otherwise appended to monitor 407 .
The computer 400 can operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 409 . Remote computer 409 can be a server, a router, a network PC, a peer device or other common network node, and typically includes many or all of the elements described above relative to computer 400 , although only a memory storage device 411 has been illustrated in FIG. 4 . The logical connections depicted in FIG. 4 include a local area network (LAN) 412 and a wide area network (WAN) 413 . Such networking environments are commonplace in offices, enterprise-wide computer networks, intranets and the Internet.
When used in a LAN networking environment, the computer 400 is connected to local network 412 through a network interface or adapter 414 . When used in a WAN networking environment, the computer 400 typically includes a modem 415 or other device for establishing a communications over wide area network 413 , such as the Internet. Modem 415 , which may be internal or external, is connected to system bus 430 via the serial port interface 406 . In a networked environment, program modules depicted relative to the computer 400 , or portions thereof, may be stored in a remote memory storage device.
It will be appreciated that the network connections shown are exemplary and other techniques for establishing a communications link between the computers can be used. The existence of any of various well-known protocols such as TCP/IP, Ethernet, FTP, HTTP and the like is presumed, and the system can be operated in a client-server configuration to permit a user to retrieve web pages from a web-based server. Any of various conventional web browsers can be used to display and manipulate data on web pages.
Ink Rendering System
An exemplary ink rendering system 500 is illustrated in FIG. 5 . Some or all of the ink rendering system 500 may be software, hardware, and/or firmware, and may be a part of the computer system 400 or a separate unit. For instance, some or all of the ink rendering system 500 may be embodied as computer code stored in the RAM 450 as part of the operating system 495 , an application program 496 , and/or another program module 497 . The ink rendering system 500 may include an ink storage 501 coupled to a rendering environment 502 , which in turn may be coupled to a graphics toolbox 503 , which in turn may be coupled to an output device 504 such as a display screen (e.g., monitor 407 ) and/or printer. The ink storage 501 may include information relating to ink including a file structure having data points representing points of the ink. The file structure may also include alternatively (or in addition to the data points) other ways to represent the ink including vectors between points, data points, stroke width information, and/or any other ink storage scheme.
Stored ink may be rendered by calling the graphics toolbox 503 to perform various functions. The ink storage 501 may maintain a list of rendering environments, one for each view in which the application renders dynamically. Each rendering environment may maintain a list of the states, one for each stroke that is currently being dynamically rendered. Each state may represent the last pen tip position (e.g., point) recorded and/or a queue of geometric regions that are further described below. In at least one embodiment, the graphics toolbox 503 has transparent painting capabilities, such as does Microsoft WINDOWS GDI+.
FIG. 6 illustrates an example of the operation of the ink rendering system 500 .
When a user draws a stroke, the ink rendering system 500 may receive a new pen tip position (step 601 ). More particularly, the ink storage 501 may receive the new pen tip position. Pen tip positions may be sampled and determined according to the position of the stylus 466 upon the digitizer 465 . Pen tip positions may further be determined according to the position of the stylus 466 within a known input window or area that defines a portion of the digitizer 466 surface. For instance, where the digitizer 465 and the monitor 407 are combined or co-extensive, there may be a predefined window displayed on the digitizer 465 within which input from the stylus 466 may be accepted, e.g., for drawing an object and/or for entering text.
Pen tip positions may be sampled at a particular rate. The sampling rate may be set at a rate at least high enough to capture sufficient pen tip positions based on the anticipated speed of a normal user. Once the new pen tip position is captured and received, the ink rendering system 500 (e.g., in particular, the ink storage 501 ) may determine the area (and/or the contour that outlines and defines the area) that is associated with the pen tip at the new position based on the size and/or shape of the virtual pen tip. This area is also known as a “pen tip instance.” For example, where the virtual pen tip is considered to be a 3-millimeter diameter circle, then the pen tip instance may be the 3-millimeter diameter circle centered at the new pen tip position. Or, where the virtual pen tip is considered to be a rectangle of 2 millimeters by 4 millimeters, then the pen tip instance may be the 2 by 4 millimeter rectangle centered at the new pen tip position. Examples of circular pen tip instances 701 , 702 , 703 , 704 are shown in FIG. 7 . The size and shape of the pen tip instance are considered properties of the pen tip position. Where the entire stroke has the same size and/or shape, then the size and/or shape may be a property of the entire stroke as opposed to each pen tip position. Of course, any shape may be used for a pen tip. Circular pen tip instances are used here for simplicity.
Each time a pen tip instance is determined, that pen tip instance (and/or the associated pen tip position) may be stored for later retrieval. Pen tip instances and/or positions may be stored as data in, e.g., RAM 450 . Data representing the position (e.g., (x, y) coordinate position), shape, and/or rotation of the pen tip instance may further be stored. Previous pen tip instances and/or positions may further be stored as part of digital ink storage such as in the serialized format described in U.S. patent application Ser. No. 09/852,799, entitled “Serial Storage of Ink and its Properties,” filed May 11, 2001.
Referring still to FIG. 6 , the ink rendering system 500 may render an ink segment that connects between the previous pen tip instance and a new pen tip instance in an ink stroke. To do so, the ink rendering system 500 may compute the new pen tip instance and/or one or more connecting quadrangles that connect between the new pen tip instance and a previous pen tip instance (step 602 ). Both the pen tip instances and the connecting quadrangles are referred to herein as “regions.”
The new pen tip instance is associated with the new pen tip position, and may be centered about the new pen tip position. The new connecting quadrangle may be determined in a variety of ways, and the method for determining the connecting quadrangle may depend upon the shapes of the new and previous pen tip instances. Various methods for determining connecting quadrangles will be discussed herein. Examples of connecting quadrangles 705 , 706 , 707 are shown in FIG. 7 . A new region may be defined as the new pen tip instance, the new connecting quadrangle, or the combination (e.g., union) of the new pen tip instance and the new connecting quadrangle. For example, the new region may be pen tip instance 704 , connecting quadrangle 707 , or the union of pen tip instance 704 and connecting quadrangle 707 . Conventional graphics toolboxes are capable of performing such a combination/union when provided with the shapes to be combined. In alternative embodiments, more than one new pen tip instance and/or new connecting quadrangle may be the new region. For instance, two consecutive new pen tip instances and their two corresponding new connecting quadrangles may be all unioned together as the new region. In this way, the method of FIG. 6 does not necessarily need to be performed between each and every pen tip instance.
The combination (e.g., union) of some or all of a plurality of previous regions may also be determined (step 603 ). These previous regions may be stored in a queue. A queue is an ordered list of items and is of a fixed, dynamic, maximum, or other controlled length. For example, a queue may have a maximum enforced length of 2, 3, or 4 items, although any length may be used. The queue may be configured as a first-in-first-out (FIFO) type queue, as in a pipeline. Where the maximum length of the FIFO queue is surpassed by adding another item to the queue, the oldest item is pushed out of the queue. The queue may separately store the actual items, or may have pointers that point to the items stored elsewhere. Where the items are stored elsewhere, they may be stored in a serialized or other format. In alternative embodiments, the items in the queue may be any items of data that represent some or all of the characteristics of pen tip positions and/or connecting quadrangles. In still further embodiments, each item in the queue may be a combined pen tip position and connecting quadrangle.
For example, referring to FIG. 9 , where the new pen tip instance is pen tip instance 905 , the new connecting quadrangle is connecting quadrangle 909 , and the queue has a maximum length of 4 regions, the queued regions to be combined may be pen tip instances 903 , 904 (two regions) and connecting quadrangles 907 , 908 (two more regions, for a total of four regions). The union of these queued regions is shown as the shaded area in FIG. 9 . The arrow 910 indicates the direction of movement of the pen tip, such that the pen tip instance 905 is the most recent and the pen tip instance 901 is the earliest in time. Note that although connecting quadrangle 906 and pen tip instance 901 may have been in the queue at an earlier time, these two regions were later pushed out of the queue due to the enforcement of its maximum length.
The ink rendering system 500 (in particular, e.g., the rendering environment 502 ) may freeze the color settings of the pixels (step 604 ) within the region defined by the combination (e.g., union) of the queued regions (e.g., the shaded area in FIG. 9 ). The combined queued regions thus become an excluding clip region that may be sent to the graphics toolbox 503 . Freezing the color settings means preventing the color and intensity of the pixels from changing. Thus, any further attempts at painting the frozen pixels will have no effect on the color and intensity of the frozen pixels. This is important where the colors are transparent, since the new connecting quadrangle (e.g., quadrangle 909 ) is likely to overlap with the union of the queued regions (e.g., the shaded area in FIG. 9 ). Without freezing the pixels in the queued regions, the overlapping portion will undergo a change in transparency when the new regions are painted. Conventional graphics toolboxes are capable of freezing the color settings of a group of pixels. An alternative to determining the union of the queued regions and then freezing the determined union region is to simply freeze each of the queued regions individually. This alternative provides the benefit of avoiding the step of determining the union. However, it increases the number of regions that need to be sent to the graphics toolbox for freezing.
The new region may be sent to the graphics toolbox 503 for painting (step 605 ). The new region may be painted in a transparent or nontransparent color as desired. After the new regions are painted, some or all of the pixels in the excluding clip region may be unfrozen (step 606 ). This step allows the color settings of the formerly frozen pixels to again be modified. More generally, the ink rendering system 500 may determine whether pixels within the new pen tip instance and/or new connecting quadrangle are also within the previous regions (such as those regions in the queue). For those pixels that are, the color settings of those pixels may not be changed. For those pixels that are in the new pen tip instance but not within any of the previous queued regions, the color settings may be changed.
The new region (e.g., connecting quadrangle 909 ) may then be pushed into the queue (step 607 ). Where the queue has rules that determine the queue length, one or more of the oldest regions may be pushed out of the queue as appropriate according to the queue rules. For example, referring to FIG. 9 , a queue having a maximum of 4 regions may currently contain the following regions in the following order: 907 , 903 , 908 , and 904 (wherein 904 is the oldest). When connecting quadrangle 909 (in this example, the new region) is pushed into the queue, then region 907 is pushed out the queue in order to maintain no more than 4 regions within the queue. Thus, the new queue would contain regions 903 , 908 , 904 , and 909 (in that order, with 903 being the oldest and 909 being the newest). The queue may have any maximum length, such as 1 region, between 2 and 4 regions inclusive, between 5 and 10 regions inclusive, or between 10 and 20 regions inclusive, 10 and 100 regions inclusive, or more. If the queue length is too short, then it is likely that a new pen tip instance from a slow-moving pen may overlap a region recently dropped from the queue, resulting in an unintended decrease in transparency in the overlapping area. This results in an unexpected rendering of ink. However, as processing time increases with queue length, using a long queue length may require the system to group numerous regions, objects, or shapes, thereby slowing the system during the rendering process and/or requiring higher processor speed to maintain adequate representation of ink in real-time.
Further, a queue length that is allowed to be too long may prevent certain desirable overlapping of transparent ink, such as when writing the script letter “e” as in FIG. 21 . For example, if the queue length were long enough to include all of points A through P of FIG. 21 , then the overlapping as shown would not occur since all of the pixels in the shown segments would be part of the excluding clip region. But if the maximum queue length were set to, e.g., 4 regions, then at point M, as the overlap begins to occur, the queue would contain only the regions of the connecting region between L and M, the region defined by the pen tip instance at point L, the connecting region between K and L, and the pen tip instance at point K. In such a case, the portion of the ink to be overlapped would not be part of the excluding clip region. It is thus desirable to use a queue length that balances the above considerations. For example, a queue with a length of 4 regions is a reasonable compromise between quality and speed for a digitizer having a resolution of about 12,000 by 9,000 pixels with a sampling rate of about 130 samples per second. The maximal queue length may depend upon the resolution of the input digitizer, the display resolution, the sampling rate, the pen speed, user settings, application settings, and/or other considerations. For instance, a larger maximal queue length may be desirable with a higher digitizer resolution and/or a higher sampling rate.
The exemplary method of FIG. 6 may be repeated for each new region. Following the example discussed above, after the new region 909 is pushed into the queue, the method of FIG. 6 may be practiced where the new region is pen tip instance 905 . Once pen tip instance 905 is painted in step 605 and the excluding clip region is unfrozen in step 606 , then the pen tip instance 905 may be pushed into the queue and pen tip instance 903 may be pushed out of the queue. This results in the queue containing regions 908 , 904 , 909 , and 905 .
As an alternative to determining the union of the queued regions and/or freezing the pixels in the union, the intersection (i.e., overlap) between the new region and one or more of the queued regions may be determined. Instead of freezing the entire union of the queued regions, it may be desirable to freeze only those pixels in the intersection. For instance, where connecting quadrangle 909 is the new region, the intersection between the new region and the union of regions 907 , 903 , 908 , and 904 may be determined (as an alternative to step 603 ), and only those pixels in the intersection would be frozen (as an alternative to step 604 ).
It is understood that one or more of the steps illustrated in FIG. 6 may be performed in a different order, combined with another step(s), and/or divided into further sub-steps as appropriate. For example, step 603 may be performed prior to step 602 or even prior to step 601 . Also, while embodiments of the present invention are described with the connections between pen tip instances being line segments, it is appreciated that the ink between the pen tip instances do not have to be actual line segments or quadrilaterals. The ink may include groupings of triangles, be bowed in shape, or assume a variety of shapes. One example of using curved lines is the advantage of being able to provide a degree of smoothing to an ink stroke.
The generation of connecting quadrangles is now discussed. Referring to FIG. 7 , a particular exemplary ink stroke may include four circular pen tip instances 701 , 702 , 703 , 704 , and three connecting quadrangles 705 , 706 , 707 . Connecting quadrangle 707 (for example) has four corners A, B, C, D, and four sides. The notation for an edge will refer to the end points of the edge. Thus, for example, the edge between corners A and B will be referred to as edge (or line or chord) AB.
The calculations for determining a connecting quadrangle may vary depending upon the relative shapes and sizes of the pen tip instances. Where the pen tip instances are both perfectly circular and of the same size, as in FIG. 7 , the connecting quadrangle 707 that connects pen tip instance 703 and 704 may be defined by lines AC, BD that are tangent to the outer edges of both pen tip instances, closed by the chords AB, CD that connect them. Note that in this example where the pen tip instances are of the same size and are circular, the chords AB, CD each defines the geometric diameter of its respective pen tip instance. Also note that in this example, the connecting quadrangles are each rectangles with orthogonal sides. However, as will be seen in further examples, the connecting quadrangles are not necessarily rectangles. They may be any type of quadrangle such as parallelograms and trapezoids.
Thus far the exemplary pen tip instances have all been identically sized circles. However, this is not always the case. Pen tip instances may be of any shape, such as circles, rectangles (including squares), triangles, ovals, blobs, stars, lines, arcs, points, or polygons. Pen tip instances may be symmetric or asymmetric. An example of an asymmetric pen tip instance is one configured to emulate the tip of a calligraphy pen. Pen tip instances may also be of varying size, such that two consecutive pen tip instances in the same set of ink may be of different sizes. Pen tip instances may further be of varying shape, such that two consecutive pen tip instances in the same set of ink may be of different shapes. Pen tip instances may further be of varying rotation, such that two consecutive pen tip instances in the same set of ink may be rotated at different angles. Of course, where the pen tip instance is an exact circle, the angle of rotation is meaningless. The rotation of a pen tip instance is also considered a property of each pen tip position and/or the entire stroke. To account for these potential variations in pen tip instance characteristics, another exemplary ink rendering system 1000 is shown in FIG. 10 . The ink rendering system 1000 includes, or is coupled to, a pen device 1000 that feeds the (x, y) coordinates of the pen tip to a contour generator 1002 . The pen device 1000 may also feed the pen tip instance size and/or rotation (e.g., angle) for each pen tip instance. The contour generator 1002 may be configured to generate a contour defining the outline of the pen tip instance based on the information provided by the pen device 1000 , as well as information about the particular pen tip instance shape selected. Alternatively, there may be a plurality of contour generators 1002 each specializing in a different shape or family of shapes. For example, there may be a first contour generator that is configured to generate contours for circular pen tip instances and a second contour generator that is configured to generate contours for rectangular (including square) pen tip instances.
The contour generator 1002 (or another specialized contour generator) may also generate contours that define the shape of the connecting quadrangles, based on the received and utilized pen tip instance characteristics and positions. The contour generator 1002 may then send the generated contours to a graphics toolbox 1004 . Where the ink is transparent, the contour generator 1002 may communicated with the graphics toolbox 1004 via a rendering environment 1003 , and the method of FIG. 6 may be implemented. The graphics toolbox 1004 may fill or freeze the provided contours as appropriate and then output pixel values to an output device 1005 such as the monitor 407 .
Referring to FIG. 11 , an exemplary ink stroke has four pen tip instances 1100 , 1101 , 1102 , 1103 of different sizes. Since the pen tip instances are circular, rotation is less important in this example and will be ignored in the present example. As this ink stroke was drawn, the size of the pen tip instances changed from medium (pen tip instance 1100 ), to larger (pen tip instances 1101 , 1102 ), and then smaller (pen tip instance 1103 ). The size, rotation, and/or pen tip shape may be adjusted automatically by a software application running on the computer 400 and/or by the user. For example, the user may have pressed then stylus/pen 466 down against the digitizer 466 with additional pressure, or may have moved the stylus/pen 466 more slowly, to select larger pen tip instances. Or the user may physically rotate the pen along its longitudinal axis in order to obtain different rotated pen tip instances. The connecting quadrangles for different-sized circular pen tip instances are, in some embodiments, generated by determining tangential lines (e.g., lines AC and BD in FIG. 11 ) between the pen tip instances and then connecting those lines at the tangents with connecting chords (e.g., chords AB, CD in FIG. 11 ).
Referring to FIG. 13 , the same method may be used as in FIG. 11 for determining connecting quadrangles (or other shapes). An exemplary ink stroke may include oval pen tip instances 1301 , 1302 . The connecting quadrangle may, in one example, be determined by calculating the lines that run tangent between the two ovals. In this case, those tangential lines would be lines AC and BD in FIG. 13 . The tangential lines would then be closed by connecting their endpoints at the tangents with lines AB, CD. Note that although these ovals are of different rotational angles, the rotation does not matter for ovals when determining the connecting quadrangles.
Next in FIG. 15 is shown an exemplary embodiment of a connecting quadrangle between two rectangular pen tip instances 1501 , 1502 , each having a different size and rotation. Although there are many possible connecting quadrangles, in this example, a connecting quadrangle 1503 connects corners A and E, corners A and C, corners C and G, and corners G and E. Another connecting quadrangle that could be used would connect corners A and H, corners D and F, corners B and G, and corners C and H. Another example is shown in FIGS. 17A and 17B , showing two different connecting quadrangles 1703 , 1704 that could be used to connect two pen tip instances 1701 , 1702 . Connecting quadrangle 1703 connects corners A and A′, corners C and C′, corners A and C, and corners A′ and C′. Connecting quadrangle 1704 connects corners B and B′, corners D and D′, corners B and D, and corners B′ and D′.
It may be desirable to utilize a connecting quadrangle that connects between the outermost portions of the two pen tip instances to be connected. For instance, where the two pen tip instances are both polygons (i.e., closed shapes having only straight edges connected at corners), it may be desirable to connect the outermost corners together to provide for the largest area possible covered by the connecting quadrangle. Such an embodiment may in many cases provide a very smooth transition between pen tip instances and a higher-quality ink that is pleasing to the eye. Also, some or all of the possible connecting quadrangles (or a subset thereof) may be determined, and the determined quadrangles may be combined together (e.g., by taking their collective union) into a single connecting region. For example, referring to FIG. 17C , all of the possible connecting quadrangles that connect the corners of the pen tip instances 1701 , 1702 are shown. A result of this is that every corner of pen tip instance 1701 is connected to every corner of pen tip instance 1702 via an edge of at least one of the connecting quadrangles. This method may be extended to any polygon having any number of sides and corners. FIG. 18 illustrates the resulting ink when all of the connecting quadrangles of FIG. 17C are combined together.
FIGS. 8 , 12 , 14 , 16 , and 18 illustrate the rendered ink that corresponds to the pen tip instances and connecting quadrangles in FIGS. 7 , 11 , 13 , 15 , and 17 C respectively. The rendered ink in these figures is a result of using the rendering system 1000 as described.
Ink Smoothing
The ink-rendering process may also include smoothing the ink. Smoothing may be performed by the rendering system 500 , 1000 , such as by the graphics toolbox 503 , 1004 , using known smoothing functions. Another example of an ink rendering system 1900 is illustrated in FIG. 19 . The ink rendering system 1900 includes a pen device 1901 , a smoothing application or subroutine 1902 , a curve-sampling application or subroutine 1903 , a contour generator application or subroutine 1904 , and/or a recipient 1905 , which may be a graphics toolbox. In operation, the pen device 1901 (e.g., a digitizer and pen) may measure the pen's (x, y) location on the digitizer. The pen device 1901 may further determine the intended rotation angle and/or size of the pen tip. The smoothing application 1902 may receive a plurality of sampled pen tip positions, pen tip instance sizes, and/or angles of pen tip instance rotation and may smooth the position, size, and/or rotation amongst the plurality of pen samples. The curve-sampling algorithm 1902 may sample the smoothed (x, y) curve, the smoothed size function, and/or the smoothed rotation function and may output samples of these smoothed functions to the contour generator 1904 . The contour generator 1904 may then generate the desired contours such as the pen tip instances and/or the connecting quadrangles, and forward these contours on to the recipient 1905 .
Smoothing may be performed on the size and/or rotation parameters. The rendering system 1900 may use any smoothing technique such as least squares fitting. To smooth ink, samples of the ink may need to be taken. These samples may be taken anywhere along the ink stroke, but at least one sampling technique is to sample the locations that were originally sampled from the pen (i.e., the sampled pen tip locations).
An exemplary smoothing function may be implemented by the ink rendering system 1900 (more particularly, by, e.g., the smoothing application 1902 ) as follows for each sample along the ink stroke:
(smoothed width) i =A 1 *(original width) 1−1 +A 2 *(original width) i +A 3 *(original width) i+1 , (1)
where A 1 , A 2 , and A 3 are constants that may be chosen as desired, i is the sample number along the sampled ink stroke, “smoothed width” is the width of the ink stroke at sample i after smoothing, and “original width” is the width of the ink stroke at sample i before smoothing. In some examples, the sum of these three constants should equal unity. A combination of A 1 =0.25, A 2 =0.5, and A 3 =0.25 works well. Angle of rotation can also be smoothed using any of the method for smoothing width, including substituting “smoothed width” and “original width” in equation 1 with “smoothed angle” and “original angle,” respectively. In another embodiment, both size and angle may be smoothed for the same ink stroke.
Referring to FIG. 20 , an exemplary ink stroke is shown having sampled points C 1 through C n (each denoted with an “x”). Each sampled point C also has an associated size and/or rotation. Size, or width, at sample point C i will be denoted as W i , and its associated rotation will be denoted as R i . It may be desirable to smooth the sampled ink as to the (x, y) positions of the sample points, the size or width of the sampled points, and/or the rotation of the sampled points.
For example, using a least-squares method for smoothing, the following algorithm may be used such that the fitting curve P minimizes the following:
min Σ{ a ( C i −P i ) 2 +b[W ( C i )− W ( P i )] 2 +c[R ( C i )− R ( P i )] 2 }, (2)
where a, b, and c are optional weighting constants; P i are the locations of the points on the fitting curve P; W(P i ) are the sizes/widths for each point P i ; and R(P i ) are rotations for each point P i . The fitting curve P may be any curve desired, such as one chosen from the family of parametric or Bezier curves. In effect, width/size and/or rotation are treated as additional dimensions other than position. Any subcombination of the dimensions in fitting a curve may also be used. For example, the third term c[R(C i )−R(P i )] 2 may be dropped from equation 2 so that rotation is not considered. Or, the second term b[W(C i )−W(P i )] 2 may be dropped from equation 2 so that width or size is not considered. Or, the first term a (C i −P i ) 2 may be dropped from equation 2 so that sample position is not considered. Alternatively, both the first and second terms, or both the first and third terms, may be dropped from equation 2 so that only rotation or only width are considered in determining the fitting curve parameters.
While exemplary systems and methods embodying the present invention are shown by way of example, it will be understood, of course, that the invention is not limited to these embodiments. Modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. For example, each of the elements of the aforementioned embodiments may be utilized alone or in combination with elements of the other embodiments. For example, while connecting quadrangles are discussed herein as a particularly advantageous shape, any shape of connecting regions other than quadrangular-shaped regions may be used. Also, while the above description discussed pen tip positions as being defined by (x, y) in a rectilinear coordinate system on the digitizer, any other coordinate system, such as polar, may be used.
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Apparatus and methods for dynamically rendering transparent ink strokes, in some situations such that the rendered ink stroke has transparency similar to physical ink while it is being drawn. For example, the ink stroke may be dynamically rendered as a stroke having uniform transparency while it is being drawn. Only the new ink segment that has most recently been added to the stroke may be drawn, and areas of the new ink segment that overlap older segments of the ink stroke may be frozen, or excluded from being re-painted.
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RELATED APPLICATIONS
[0001] The present invention claims the benefit of U.S. Provisional Application Serial No. 60/399,587 entitled “Microcellular RF Transmission With Baseband Signal Delivery Via a Wireline Connection” and filed Jul. 30, 2002.
FIELD OF THE INVENTION
[0002] The present invention relates generally to improvements to wireless communication networks, and more particularly to advantageous techniques for radio frequency (rf) transmission in a microcellular environment. To this end, a plurality of low cost base remotes or radio frequency (rf) heads are connected by a wireline to an improved master base transceiver station located remotely from the rf heads to provide a flexible, cost effective network with excellent service coverage as addressed in greater detail below.
BACKGROUND OF THE INVENTION
[0003] In one conventional network, a conventional macrocell network 100 shown in FIG. 1, the wireless network 100 is connected to a local phone system network (PSTN) 50 to provide wireless customers with access to wired phone network customers. The network 100 includes a plurality of n mobile switching centers (MSCs) 120 1 , 120 2 . . . 120 n connected to a large plurality of base transceiver stations (BTSs) such as BTSs 131 1 , 131 2 , 131 3 , and 132 . Each MSC has a number of base station controllers, such as base station controllers (BSCs) 125 1 and 125 2 shown for the MSC 120 1 of FIG. 1. The BTSs 131 1 , 131 2 , 131 3 , and 132 are connected to the BSCs by T 1 lines 127 1 , 127 2 127 3 and 128 , respectively. The BSCs may control one or more base transceiver station. The exemplary BSC 125 controls BTS 131 1 , BTS 131 2 and BTS 131 3 while the exemplary BSC 125 2 controls BTS 132 1 . For the sake of ease of illustration, additional BSCs for MSCs 120 2 . . . 120 n are not shown and neither are the large number of additional BTSs controlled by these MSCs.
[0004] Although other mounting arrangements are known as will be addressed in greater detail below, a common arrangement for mounting BTSs like those in a typical macrocell network is to collocate them with a broadcast tower, such as towers 141 1 , 141 2 , 141 3 and 142 1 , which are schematically illustrated in FIG. 1. A hallmark of this macrocell approach is that the entire base station and its tower are located at a central point with respect to an area where coverage is needed. These towers are typically tall and expensive. Additionally, it is becoming increasingly difficult to get regulatory or other government approval for such towers and transceivers in new locations where coverage is needed as networks seek to expand. “Not in my backyard” is a common expression applicable to the effort to locate such new towers.
[0005] As a result of such difficulties and the expense attendant in such mounting arrangements, a BTS may commonly broadcast at the maximum power allowable to cover the maximum area of coverage consistent with the network standards and any governing broadcast laws. Thus, the BTS of a macrocell network is typically a high power, large, high cost device and little consideration is given to stripping the cost of logic out of the units as there is little incentive to do so. Whether the BTS broadcasts at maximum power levels or lower levels, which is the case as capacity limitations require the nearby placement of additional high power cell sites, the high cost of a high power cell site is not reduced. Thus, over the course of time, high power transmitters that were already installed are being used to provide the equivalent of low power coverage.
[0006] A variety of approaches to providing more effective and lower cost network coverage have been put forward. Among these are the approaches described in U.S. Pat. Nos. 5,787,344 and 6,128,496 which are incorporated by reference herein in their entirety. One of the inventors of the present invention is also the inventor of the above patents. Briefly, these patents describe a technique in which a central base transceiver station is coupled to a base station controller. The central base transceiver station wirelessly communicates at a higher power level directly with mobiles in a larger zone of coverage. It also communicates via a directional radio link with a number of decentral transceiver stations for a plurality of lower power cells. The decentral transceiver stations in turn communicate directly with mobiles within their own smaller zones of coverage. Like the macrocell approach, the entirety of a central base transceiver station for the above described patented approach is located central to an area for which coverage is needed and both the central base transceiver station and the decentral transceiver stations include redundant digital logic circuitry driving up the cost of these units which are numerous in a large network.
SUMMARY OF THE INVENTION
[0007] The present invention addresses problems such as those identified above in connection with the macrocell and previously patented approaches, as well as other problems which will be apparent both from the discussion which follows and to those of ordinary skill in the art in light of the present discussion. According to one aspect of the present invention, the bulk of the digital logic is stripped out of a base transceiver station resulting in a master base transceiver station (MBTS) without any rf components and with the bulk of the digital processing components, and a separate base station remote including the rf components. The MBTS preferably comprises a base station kernel and a base station mother, the details of which are addressed further below. The MBTS is located remote from a plurality of low cost base station remotes and is connected preferably through wirelines to these remotes. In a presently preferred embodiment, the remotes will be mounted on preexisiting telephone poles and will be connected to their MBTS by an existing telephone line, such as a leased T1 line. Alternatively, other broadband connections, such as DSL, cable modem, fiberlinks, or the like, may be employed. It will be recognized that where the phone lines are buried underground, it may be necessary to employ a different approach such as that of the above described patents to fill in the network's coverage. Each remote has a limited amount of digital logic circuitry which may vary depending upon the application. Digital signals are preferably transferred between the MBTS and the remotes.
[0008] In one embodiment, the encoding and decoding function logic is stripped out of the base station remotes and is included in the base station kernel. In this case, a baseband interface is employed with all encoding and decoding done in the MBTS and the modulation done in the remotes. In an alternative embodiment, if it is desired to present less of a load to the wireline connection between the base station mother and the remotes, then the encoding and decoding circuitry is also designed into the remotes. A further possible split of the functionality is to locate the encoding in the MBTS and the decoding in the remotes.
[0009] Among its several advantages, the above discussed approach and various aspects of the present invention allow the clustering of relatively low cost, low power remotes which are capable of communicating in a simulcast mode of operation and do not need to be located near the MBTS providing their signaling. Also, they do not need to be central to a large area of desired coverage. It will be recognized that additional network capacity can be added by reconfiguring the remotes into different cluster patterns. For example, if one imagines a network of 100 remotes arranged in 10 clusters of 10 remotes, with appropriate software and control logic, these same remotes can be rearranged to form 10 clusters of 9 remotes and 1 cluster of 10 remotes for a new total of 11 clusters. A cluster may be viewed as equivalent to a sector or cell in a traditional high power cell site arrangement. As the remotes can be mounted on existing telephone poles, other pole structures, billboards, rooftops, or other preexisting structures, any holes in the network or additional service areas can be relatively easily filled in or added, respectively. With respect to existing telephone poles, it is envisaged the remote can be physically mounted at or near the top of the pole, or an extension to the pole, such as a street light arm, and will also connect to its MBTS through a phone line carried by the pole. It is important to note that because of the wireline connection, the MBTS can be located wherever it is desired and independent of the placement of the remote units. It can and preferably will be located indoors where it is not susceptible to the ravages of, heat, cold, rain, snow, high wind and other weather conditions which may be faced by tower mounted base stations.
[0010] It will also be recognized that the present techniques may be readily adapted to various existing systems, such as 2G and 3G mobile networks like GSM, CDMA, WiFi, or UMTS, and the like, as well as further systems not yet on the drawing board.
[0011] Additionally, the architecture can support a wide variety of digital interfaces for connecting the base station mothers and the remotes, for example, T1/E1, or higher, like T3/E3 lines, fiber optic links, wireless T1/E1, or higher, digital coaxial links, such as cable modem interfaces, standard telephone cables, and DSL lines to name a few. While the discussion which follows will be principally in terms of T1 lines as the presently preferred connection, it will be recognized that other connections can be made depending on the costs and benefits for a particular environment and application. For example, if the base station mother or a remote mother is in a building, existing telephone cables can be used to connect the remotes to the mother. However, an analysis of the falling costs of T1 lines and the rising costs of towers and the decreasing availability of suitable locations for macrocell base transceiver stations demonstrates a simple and compelling case for the rapidly improving cost effectiveness of the techniques of the present invention.
[0012] A more complete understanding of the present invention, as well as further features and advantages of the invention, will be apparent from the following Detailed Description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a block diagram illustrating a conventional prior art macrocell communication network design;
[0014] [0014]FIG. 2 shows a master base transceiver station comprising a base station kernel operating in conjunction with a base station mother to control a plurality of stripped down, low power, low cost base station remotes in accordance with the present invention;
[0015] [0015]FIG. 3 illustrates further details of a base station remote in accordance with the present invention;
[0016] [0016]FIG. 4 illustrates an exemplary clustering arrangement utilizing a master base transceiver station with a plurality of base station mothers controlling clusters of remotes in accordance with the present invention.
DETAILED DESCRIPTION
[0017] [0017]FIG. 2 illustrates various aspects of a master base transceiver station (MBTS) 200 in accordance with the present invention. As shown in FIG. 2, a prior art BTS such as the BTS 131 , of FIG. 1 previously including full digital logic and control functionality, and collocated with an associated tower 141 1 or the like and connected by a wire connection such as the T1 line 131 , to its base station controller 125 , has been advantageously redefined and redesigned in accordance with the present invention as described below.
[0018] As seen in FIG. 2, the prior art BTS has been redesigned to separate the bulk of its logical functions into the MBTS 200 which comprises a base station kernel 210 and a base station mother 220 . The rf functional components have been maintained in relatively low cost, small size base station remotes, with three such remotes 240 1 , 240 2 and 240 3 shown in FIG. 2. These remotes are connected to base station mother 220 by T1 lines, 230 1 , 230 2 and 230 3 , respectively. It will be recognized that while only three remotes are shown for ease of illustration that the number of remotes, n, can be any desired number. While T1 lines are shown as presently preferred, it will be recognized that the link between the remotes and the base station can be based on circuit switched connections, like T1, or Internet protocol (IP) based, such as the Internet.
[0019] For a GSM embodiment, the base station kernel 220 will combine the logical functions for software layer 2 , layer 3 and part of layer 1 and produces at an output 212 connected to an input 222 of the base station mother 220 a baseband output signal. The base station mother 220 will include interface circuitry for broadcasting the baseband output signal from the base station kernel 220 to the respective T1 lines 230 1 , 230 2 , and 230 3 on the downlink path to the remotes 240 1 , 240 2 , and 240 3 . In the uplink path, base station mother 220 will include appropriate receive circuitry to combine the multiple signals from the remotes, to select the signal from the cell in which a mobile is located, or the like.
[0020] [0020]FIG. 3 illustrates a network 300 including an MBTS 305 including a base station kernel 310 and base station mother 320 . MTBS 305 is connected by a T1 line 330 to a base station remote 340 which transmits to mobile stations such as cell phone 350 . FIG. 3 shows further details of the base station remote 340 which as shown in FIG. 3 includes appropriate line interface circuitry 342 for connecting to the T1 line 330 , network management software 344 and GSM frequency support transmission circuitry 346 for supporting 1 . . . x channels as desired for a particular application, and rf transmit and receive antennas 348 to wirelessly communicate with mobiles, such as exemplary mobile 350 , in the area of coverage of the remote 340 .
[0021] Exemplary functions to be provided by the network management software are device configuration with respect to the frequencies of transmission, output power and the like, alarm handling, for example, when a transmitter overheats, a synthesizer is out of lock or the like, performance management including monitoring the load of the remote, average output power and the like, and authorization and security functions, such as username, passwords, encryption and the like. Part of the circuitry 346 operates as a modulator to up convert the signals to be transmitted to the antennas 348 . Circuitry 346 receives as an input a baseband signal and connects it to an rf output. It may suitably include a modulator, upconverter, power amplifier (PA), receiver, downconverter, and a demodulator; however, these components and functions are exemplary and the support transmission circuitry 346 may be variously implemented. While a T1 interface is specifically addressed, it will be recognized that appropriate interfaces for E1, DSL, optical, telephone wires, and wireless T1/E1 connections may be included as desired.
[0022] [0022]FIG. 4 illustrates a network 400 in which an MBTS 405 including a base station kernel 410 and two base station mothers 420 1 and 420 2 provides control signals using two sets 430 1 and 430 2 of five leased T1 lines to clusters 440 1 and 440 2 of remote stations. Each cluster represents a cell. The remote stations each comprise five individual stations transmitting at the same frequency to mobiles in their coverage area, such as mobiles 450 1 and 450 2 , respectively. All of the remotes in cluster 440 1 are transmitting at a first frequency, f 1 , and all of the remotes in cluster 440 2 are transmitting at a second frequency, f 2 .
[0023] While five base station remotes are shown in each cluster, it will be recognized that N base station remotes may be employed in a cell area with a call being transmitted throughout that cell area. Similarly, while MBTS 405 is shown as having two base station mothers 420 1 and 4202 2 , each controlling a cell area, it will be recognized that M base station mothers can be employed to serve M cell areas. A particular advantage of the present approach is that with appropriate circuitry to handle line delay the MBTS 405 can be located anywhere. Various clustering techniques can advantageously be employed as known in the art.
[0024] Additionally, it is presently preferred that in a simulcast environment that the base station mother includes suitable software and hardware to determine which data received from a plurality of remote stations should be used. In other words, if eight remotes are transmitting and a mobile's transmission is only being fully received by one remote, the circuitry will realize seven are received compromised transmissions and one is receiving the full transmission and act accordingly. Alternatively, if a mobile is in an area overlapped by two remotes, so that the mother is receiving some signal from both, the mother can combine the two signals. Thus, the mother can have both selective and combining modes of operation. Also, in a presently preferred embodiment suitable hardware and software will be included in a network with a large number of remotes to control the simulcasting of these remotes in clusters and allowing the simple reconfiguration of the clusters as desired to address the changing needs of the network. As indicated above, for example, a network with 10 clusters of 10 remotes may be reconfigured in a highly advantageous way to form a new network with 11 clusters, 10 with 9 remotes and 1 with 10 remotes, without adding additional remotes. Thus, by reducing the cluster size, cells can be added without the need for new additional sites to be added, unlike conventional approaches. Advantageously, a network can be rolled out with one time setup for an originally desired coverage plan. Then, it can be simply reconfigured to meet additional capacity demand.
[0025] While the present invention is disclosed in the context of a presently preferred embodiment, it will be recognized that a wide variety of implementations may be employed by persons of ordinary skill in the art consistent with the above discussion and the claims which follow below.
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Techniques are described for splitting a base transceiver station into digital and rf functions. With relatively low cost simulcasting clusters of rf remotes located to define coverage areas and master base transceiver stations connected to the rf remotes by suitable wireline connectors, such as Ti lines, the bulk of the digital functions can be located anywhere that is desired. Numerous, small, low cost, low power rf remotes may be advantageously mounted on existing structures such as light poles, telephone poles, and the like to achieve desired areas of coverage cost effectively and with a high degree of flexibility with respect to meeting future increases in need for additional capacity.
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RELATED APPLICATION INFORMATION
This application is related to and claims priority from U.S. Application No. 60/226,341, filed Aug. 18, 2000, entitled “Automated Internet Touring System Tailored To User-Specific Qualities,” which is incorporated herein by reference.
NOTICE OF COPYRIGHTS AND TRADE DRESS
A portion of the disclosure of this patent document contains material, which is subject to copyright protection. This patent document may show and/or describe matter, which is or may become trade dress of the owner. The copyright and trade dress owner has no objection to the facsimile reproduction by any one of the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyright and trade dress rights whatsoever.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to providing content of interest to a user. The present invention further relates to recommending web pages to a user of the World Wide Web based upon the currently viewed web page.
2. Description of Related Art
The World Wide Web is a collection of millions of linked web sites, electronic documents and files that are stored on computers throughout the world. The World Wide Web includes Web sites that literally relate to millions of different subjects, which may or may not be of interest to a person who is surfing the web.
A user typically employs a browser to access Web sites that are of interest to the user. The user can learn of Web sites of interest by either learning of the site through friends or through the media. Another way to learn of Web sites is to use a search engine to search the Web. The user typically types key words into a search engine Web page. The search engine then returns a list of one or more Web sites that relate to the keywords. This can be confusing for novice users who are unfamiliar with computers and the Web. Moreover, the use of search engines can also be frustrating for experienced users as the search engines may sometimes turn up sites that are unrelated to the keywords. Even worse, the search engines may sometimes inadvertently turn up sites that are of an objectionable nature to a particular user.
It would be desirable for a program or an online service to automatically assist a user with browsing to Web sites that are particularly tailored to the user's interests. This would allow novice user to quickly become accustomed to using the Web in a relatively easy manner. Such a program or service would also provide experienced users with a more fulfilling online experience.
Several attempts have been made at providing users with automated browsing assistance. In a system called “Ringo” developed at the MIT Media-Lab in the mid-1990s, personalized recommendations were made to a user based upon similarities between the interest profile of that user and the interest profiles of other users. Ringo was designed for making recommendations of music albums and artists, though it applied to Web browsing. In Ringo, he user profiles were developed by having the user rate content.
Other browsing aids, such as the eTour service of eTour, Inc., also depended on the development of user profiles. The quality of profile-based services depends on the extent and accuracy of each user's profile. Thus, in some services, a considerable number of users, providing considerable amount of ratings, are required before they become useful. Furthermore, profile-based services cannot easily account for changing tastes of the users. Finally, profile-based services face a considerable obstacle in that, before a user can see the benefits of the service, the user must register and provide a profile. Many users prefer to browse anonymously, and studies have shown that users have relatively short attention spans.
Prior art content location aids are typically server-based. For example, the eTour service requires the user to register with their server, and the user must visit the eTour site each time a user wishes to activate the service during a session. Other server-based aids have been provided in web sites which allow users to make purchases from an on-line catalog. For example, in some web sites, when a user identifies a particular item in the catalog of interest, then the server, when dynamically creating a web for the user, may identify other products in the catalogue which may be of interest to the user. Such server-based aids are limited, in that they only work with a single on-line catalogue, and require that the user remain in contact with the server. These server-based aids can be slow, both because of the demands placed upon the server, and the need to make repeated data transfers over the telecommunications infrastructure.
SUMMARY OF THE INVENTION
In accordance with the present invention, an electronic content recommendation service is provided which can act as an aid to a user in obtaining electronic content. The service is provided using software, apparatus and methods in accordance with the invention. The service may be operated without user profiles or user registration. However, the service nonetheless can provide highly useful recommendation for electronic content to browse.
In accordance with the invention, a user's browsing of electronic content is monitored. For each unit of electronic content output by the user's browser, one or more units of electronic content (e.g., web pages) are recommended to the user. The user may then load a recommended unit of electronic content.
Recommendation is based upon a system of categorization. A number of units of electronic content are identified as fitting into predefined categories of human interest. During a user's browsing, the unit of electronic content loaded in the user's browser is determined to be in at least one of the predefined categories. Recommendations of electronic content to browse are drawn from lists of units of electronic content which were previously placed into the category of the current unit of electronic content.
DESCRIPTION OF THE DRAWINGS
Further objects of this invention, together with additional features contributing thereto and advantages accruing therefrom, will be apparent from the following description of an embodiment of the present invention which is shown in the accompanying drawings with like reference numerals indicating corresponding parts throughout and which is to be read in conjunction with the following drawings, wherein:
FIG. 1 is a first block diagram of a network data distribution system in accordance with the invention.
FIG. 2 is a second block diagram of the network data distribution system in accordance with the present invention.
FIG. 3 is a representation of a display of a local device having a client window and a browser window in accordance with the invention.
FIG. 4 is a flow chart of a method of recommending web pages to a user in accordance with the invention.
These and additional embodiments of the invention may now be better understood by turning to the following detailed description wherein an illustrated embodiment is described.
DETAILED DESCRIPTION OF THE INVENTION
Throughout this description, the embodiments and examples shown should be considered as exemplars, rather than limitations on the apparatus and methods of the present invention.
THE SYSTEM AND APPARATUS OF THE INVENTION
With reference to FIG. 1 , there is shown a block diagram of a network data distribution system compatible with the invention. FIG. 1 includes a local device 100 , a data access network 120 , a recommendation server 130 and a web server 150 .
The local device 100 may be a client computer that is configured to access the web server 150 and the recommendation server 130 via the data access network 120 . The client computer may be, for example, a PC running a Microsoft Windows operating system. The local device 100 includes an output device, such as display 101 , and an input device, such as keyboard 102 and/or pointing device 103 (e.g., mouse, track ball, light pen, or data glove). The local device 100 may also be, for example, an Internet appliance, network computer (NC), or a data-enabled device such as a portable digital assistant (PDA), mobile phone, refrigerator, automobile, etc. The particular type of device of the local device 100 is not considered to be important so long as the local device 100 can provide some measure of individual user interactivity with a source of electronic content via a data access network in a client/server fashion.
The data access network 120 provides lower layer network support for the local device 100 to interact with servers in the network data distribution system, including the recommendation server 130 and the web server 150 . The data access network 120 may comprise a common or private bi-directional telecommunications network, a public switched telephone network (PSTN), a cable-based telecommunication network, a LAN, a WAN, a wireless network, any of which are coupled with or overlaid by a TCP/IP network (e.g., the Internet or an intranet).
The web server 150 may be of the type known in the art and has the ability to serve web pages to the local device 100 , as requested in the manner known in the art. It should be appreciated that the web server 150 is representative of any source of web pages and electronic content available to the local device 100 . Thus, for example, the web server 150 could be accessible from the Internet, or it could be a part of an intranet, and represents any number of servers.
The recommendation server 130 is a computer system, such as a server computer. The recommendation server 130 may be considered to represent a number of physical devices which as a group provide the indicated network services. For example, the recommendation server 130 could include a web server plus a database server. The recommendation server 130 transmits certain data to the local device 100 as described further below. The recommendation server 130 may also act as a recipient of certain information transmitted by the local device 100 , as described further below.
Referring now to FIG. 2 , there is shown a block diagram of another view of the network data distribution system of FIG. 1 . The system comprises a client 110 , the data access network 120 , the recommendation server 130 a recommendation database 180 and a page categorization database 140 .
A browser 160 is also shown. A “browser” is software that provides interactive utilization of units of electronic content, such as web pages. The browser 160 may be Microsoft Internet Explorer or Netscape Navigator. The browser 160 may alternatively be a microbrowser used to browse units of WML or HDML based electronic content on a wireless handset. When the local device 100 is connected to the web server 150 through the data access network 120 , the user of the local device browses the web server 150 from the local device 100 using the browser 160 . The browser 160 need not be stored on the local device 100 . The user, from the local device 100 , can exercise control over what electronic content is requested and thus output to the output device of the local device 100 .
The client 110 is software operative on the local device 100 . The client 110 may be an independent application program, a DLL or other logical grouping of routines. The client 110 need not be stored on the local device 100 . The client 110 may be integrated with the browser 160 , an operating system, or other software.
The recommendation database 180 and the page categorization database 140 store and provide data regarding categories, web pages and recommendations. The page categorization database 140 supports category look-up for electronic content. The recommendation database 180 supports category-based recommendations. Although described herein as separate entities, the recommendation database 180 and the page categorization database 140 may be combined into a single database with appropriate fields and controls, and may be otherwise distributed.
A copy or subset of the recommendation database 180 and the page categorization database 140 , referred to as local cache 170 , may also be stored in the local device 100 to speed the operation of the client 110 . The client 110 and recommendation server 130 may cooperate to update the local cache 170 , and to have the recommendation database 180 and the page categorization database 140 accessed when the local cache 170 is inadequate or unavailable. The decision on what, if anything, to place into the local cache 170 depends on such factors as the capabilities of the client 110 , the recommendation server 130 , the databases 140 , 180 , and the data access network 120 . Decisions on what and how much to store in the local cache 170 may be influenced by factors such as popularity of an object to a particular user and popularity to all or a group of users.
One aspect of the present invention is the use of “categories.” A category has two components. First, there is a label associated with the category which in most embodiments is descriptive of the category. Second, there is a scope for the category. The category scopes may be precisely defined, or may be loosely defined. The scopes may be defined through automated and/or manual techniques. Scopes may be defined using principles of linguistics and cognitive science. The particular labels and scopes, and the method of creating the labels and scopes, is not critical to the invention. Furthermore, the labels and scopes to be used are generally dependant on the embodiment of the invention.
In general, the categories should be logically distinct, though some overlap may be inevitable. The categories should be of human interest, which is itself difficult to precisely define. Just as there are numerous techniques for selecting categories, so too there are numerous techniques for categorizing units of electronic content such as web pages, and for selecting which unit of electronic content to recommend for a given category. In the embodiment currently contemplated, formulation of the page categorization database 140 and the recommendation database 180 involves human input. In the embodiment currently contemplated, the page categorization database 140 comprises domain names and URLs which are selected based upon popularity. Objects (e.g., domain names and URLs which resolve to web pages) in the page categorization database 140 are categorized by parsing the HTML of the corresponding web page, distilling the text of the pages, and deriving a sense of the text of each page. The senses may be made using principles of linguistics and cognitive science. The senses are used to select one or more categories into which the web page fits. The list may include ratings of relevance of a given web page to its categories.
Referring now to FIG. 3 , there is shown the display 101 having a client window 350 and a browser window 300 . The client window 200 is generated and controlled by the client 110 . The browser window 300 is generated and controlled by the browser 160 . The browser window 300 is familiar to those skilled in the art, so the particulars are not described further herein. Further information regarding the use of most browsers and their technical specifications is abundantly available.
The browser window 300 includes a display pane 310 , an address bar 320 and a title bar 330 . The display pane 310 is a region of the browser window 300 wherein the browser 160 causes web pages received by the browser 160 to be displayed. The address bar 320 is another region of the browser window 300 . The browser 160 displays URLs in the address bar 320 corresponding to the web page currently displayed in the display pane 310 . The user can also enter a URL into the address bar 320 , and the browser 160 will attempt to load the web page or other object to which the entered URL points. The address bar 320 may be hidden. However, there is an object associated with the address bar which, in common practice, stores the URL for the currently displayed web page. The primary feature of the title bar 330 is that it displays the title of the browser 160 . Another feature of most browsers is that the title bar 330 displays the title of the web page then displayed in the display pane 310 .
The client window 350 includes a title bar 351 and a number of operational icons 352 , 353 on the title bar 351 . The title bar 351 may be used for identifying the client 110 . The client window 350 as shown includes a recommendation pane 360 . The recommendation pane 360 includes a prompt 361 , a category display area 362 and an activation button 363 . The client window 350 and the recommendation pane 360 are shown having a conventional rectangular shape. However, the client window 350 and the recommendation pane 360 may define any of a wide variety of regular or irregular shapes.
The client window 350 is displayed on top of the browser window 300 . The client window 350 may be configured to attach to an edge of the browser window 300 , and always remain visible and on top of the browser window 300 (persistent). The location of the client window 350 may be predefined, selectable by the user, or selected by a server remotely. In one embodiment, the client window 350 is attached to the title bar 330 of the browser window 300 . In other embodiments, the client window 350 , or parts of the client window 350 , may be integrated into the browser window 300 . For example, the title bar 351 of the client window 350 may be eliminated, and the contents of the recommendation pane 360 fixed in the browser window 300 .
The operational icons 352 , 353 on the title bar 351 include a close icon 352 and a help icon 353 . Activation of the close icon 352 causes client 110 to close the recommendation pane 360 , although the title bar 351 of the client window 350 remains displayed. The help icon 353 may be used for providing help to the user. The category display area 362 is used for displaying the label associated with the category of the web page being displayed in the browser display pane 310 . The prompt 361 is static text which, when combined with the display in the category display area 362 , conveys a message to the user of the availability of a recommendation. The activation button 363 is used by the user to accept the recommendation.
Variations of the client window 350 , and corresponding functionality of the client 110 are within the scope of the invention. The category display area 362 may be a drop down list. In such an embodiment, the drop down list could include all of the categories in which the current web page falls, and could list sub-categories. The client window 350 may provide a selectable display of the URLs, page names, or site names of the recommended web pages.
THE METHODS OF THE INVENTION
Referring now to FIG. 4 , there is shown a flow chart of a method of recommending electronic content to a user in accordance with the invention. As will be seen, in contrast with prior art systems, this method may be practiced without any particular information about the user, such as a user profile. Because the method is automatic from a user perspective, a user need not register or provide information before gaining its benefits.
After the method begins (step 405 ), the client 110 activates on the local device 100 . The client 110 may activate automatically, for example when the browser 160 activates (step 410 ). The process by which the client 110 is installed on the local device 100 is not significant. The client 110 may be provided to users for free or for a fee. The recommendation service of the invention may be provided for free or for a fee. Fees may be assessed through well known payment systems, including through artificial media of exchange such as RocketCash.
Once activated, the client 110 can monitor the browser 160 (step 415 ). One reason that the client 110 monitors the browser is to know when the user has browsed to a new web page. By monitoring the browser's address bar object, when the browser 160 requests a web page, the client 110 can recognizes that the address bar object has changed. This is only one of many techniques for the client 110 to learn that the current web page has changed.
If there is a new web page in the browser 160 , then the category of the newly current web page is determined (step 420 ). The address bar object stores the URL of the current web page. By copying the contents of the address bar object, the client 110 can use the URL of the current web page as a basis for determining the category of the current web page.
As explained above, the recommendation server 130 has access to the page categorization database 140 , which can be copied to the local device 100 and accessed directly by the client 110 . Depending on the location and distribution of the page categorization database (stored in the local cache 170 or the full copy 140 ), the URL from the address bar object may be used to obtain the corresponding category from the categorization database. This may also depend on whether the categorization database 140 stores complete URLs, portions such as domain names, keywords, etc.
Categorization of the current web page may be done “on the fly.” For example, the same techniques discussed above for batch categorization to create the page categorization database 140 may be used on an as-needed basis during browsing. A look-up table may be useful in any event to correlate between categories and characteristics of web pages.
Although the category determination can be made by initially copying the URL from the address bar object, other techniques can be used to determine the category of the current web page. For example, techniques such as screen-scraping, data-stream sniffing, and copying other objects used by the browser are available to obtain information about the current web page. This information may be used as described above for categorization.
Once the category of the current web page is known, the client 110 can select a web page to recommend (step 425 ). There may be only one web page recommended, or a number of web pages may be selected to recommend. The recommendation is automatic (i.e., active), and does not require the user to do anything to obtain the recommendations. Furthermore, recommendations may be made without reference to user profiles of any kind.
To make a recommendation, the client 110 consults the recommendation data in the local cache 170 , in the recommendation database 180 , or may cooperate with the recommendation server 130 to access the recommendation database 180 . In the embodiment currently contemplated, web pages to recommend for each category are selected in advance. This includes some measure of human involvement to refine the recommendations. When needed by the client 110 , recommendations may be made in a way that minimizes the chance that a commendation is made twice. Recommendations may also be made on a preferential basis, and may be made on exchange of consideration (e.g., paid placement). Recommendations can also be made on numerous other factors, including popularity, fit in a category, and relationships.
Furthermore, recommendations can be made by synthesizing characteristics from a user's historical web browsing. Since the client 110 monitors web browsing, a history of web pages browsed may be maintained and utilized to enhance the recommendations. For example, it may be desirable to not recommend pages which the user has already browsed, which the user has browsed them within a certain period of time, or which are similar to pages the user has browsed or recently browsed.
It is believed that, for the client 110 to be effective, its use should instill trust in the user. This theory is drawn from the experience of prior art search engines. Thus, although short-term revenues may be enhanced by accepting paid placements which are not particularly relevant to a category, this may ultimately reduce usage of the client 110 because of reduced user trust.
After the client 110 has obtained one or more recommendations for the current web page (step 425 ), the client 110 generates a message on the output device 101 which informs the user of the availability of a recommendation (step 430 ). This may be achieved by displaying the category of the current web page in the category display area 362 ( FIG. 3 ), and displaying the activation icon 363 . The display of the category in the category display area 362 may occur after the category of the current web page has been determined in step 420 , after the recommendation(s) are available in step 425 .
The user then may provide input to the client 110 indicative of the user's desire to activate the recommendation (step 440 ). If there is more than one recommendation, the activation icon 363 may be used to select the first recommended web page. The user may be provided with the opportunity to select from a list of recommended web pages, for example with a drop down list. If the user chooses not to accept the recommendation, then browsing continues (step 445 ), and the client 110 continues to monitor the browser (step 415 ).
As an alternative to step 440 following step 425 , they may be reversed. That is, the user may provide input to the client 110 indicative of the user's desire to activate a recommendation, and then the recommendation may be obtained.
If the user accepts a recommendation, then the client 110 causes the browser 160 to request the recommended web page (step 450 ). If the user could select from more than one recommendation, then the client 110 causes the browser 160 to request the recommended web page which the user selected. The web browser then requests and loads the recommended web page. The recommended web page may be displayed in the same browser window 300 as the current web page, or may be displayed in a new or other window.
After the user has selected a first recommended web page (step 440 ), the user may continue to accept recommendations from the same category (step 455 ). This step 455 may be performed in a number of ways. As mentioned, in step 425 several web pages may be selected for recommendation. In such a case, the client 110 maintains a list of recommendations and the user may select a next recommendation by activating the activation icon 363 . The activation icon 363 may change appearance to reflect that more recommendations are available. As an alternative to selecting multiple web pages to recommend in step 425 , after a recommended web page has been loaded, it can be treated as the current web page, with control returning to step 415 . By providing successive recommendations, the user may be provided with an electronic tour of web pages which are likely to be of interest.
In the currently contemplated embodiment, the client 110 continues operating so long as the browser 160 is active. Thus, the client window 350 is never completely closed. Since the client window 350 may be embodied in other forms, or eliminated as described above, manners of hiding operative features of the client 110 or closing the client 110 are within the scope of the invention.
The client 110 may provide additional avenues for making recommendations of web pages to the user. The user may be prompted to enter or select one or more key words, categories or linguistic senses, provided as a whole or limited by relevant criteria as discussed above. Recommendations may then be made from the user input alone or in conjunction with analysis of the current web page.
Although exemplary embodiments of the present invention have been shown and described, it will be apparent to those having ordinary skill in the art that a number of changes, modifications, or alterations to the invention as described herein may be made, none of which depart from the spirit of the present invention. All such changes, modifications and alterations should therefore be seen as within the scope of the present invention.
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An electronic content recommendation service is provided which can act as an aid to a user in obtaining electronic content. A user's browsing of electronic content is monitored. For each unit of electronic content output by the user's browser, one or more units of electronic content (e.g., web pages) are recommended to the user. The user may then load a recommended unit of electronic content. Recommendation is based upon a system of categorization. A number of units of electronic content are identified as fitting into predefined categories of human interest. During a user's browsing, the unit of electronic content loaded in the user's browser is determined to be in at least one of the predefined categories. Recommendations of electronic content to browse are drawn from lists of units of electronic content which were previously placed into the category of the current unit of electronic content.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a wheel spin control apparatus for use in an automotive vehicle for minimizing the spinning of a driven wheel and, more particularly, to the control apparatus operable to control both the braking force, delivered to the driven wheel, and the engine torque, thereby to quickly and effectively minimize the spinning of the driven wheel of an automotive vehicle which would occur, during, for example, the start or acceleration of the automotive vehicle.
2. Description of the Prior Art
An automotive vehicle usually has at least one pair of driven wheels which are coupled together through a differential gear assembly which is in turn coupled with an engine. It has often been experienced that, when a driver starts or accelerates the automotive vehicle, for example, with a full throttle open, an extremely high engine torque is delivered to the driven wheels so that the drive forces applied to the driven wheels will be greater than the frictional forces between the tires on the driven wheels and the road surface. Accordingly, the driven wheels slip or spin excessively relative to the road surface. An efficient and effective transfer of the wheel traction from the tires to the road surface can be achieved when the speeds of the driven wheels' rotations slightly exceed the vehicle speed with a small amount of spin occurring between the driven wheel tire and the road surface. Thus, the excessive spin results in a loss of the engine power and a reduction of driving efficienty. This is also true even in the case where the automotive vehicle is driven at a moderate engine torque, but starts on a slippery road surface.
As such, numerous wheel spin control apparatuses have previously been suggested for relieving the excessive slip to a value required to achieve the maximum traction, that is, the maximized transfer of a tractive force from the driven wheels onto the road surface. For example, some are designed to apply a braking force to the driven wheel and others are designed to reduce the engine torque in the event that the detection of the wheel speeds indicates incipient spin conditions.
A combined version of these two types is disclosed, for example, in Japanese Laid-open Patent Publication No. 58-16948, laid open to public inspection on Jan. 31, 1983. According to this publication, the wheel spin control apparatus is selectively operable in two modes; the braking control mode and the torque control mode. The braking control mode is brought into effect only when one of the left-hand and right-hand driven wheels tends to spin, so that the braking force can be applied to such one of the driven wheels, thereby to substantially eliminate an unbalanced condition of the driven wheels. On the other hand, the torque control mode is brought into effect when both the left-hand and right-hand driven wheels tend to spin and, also, when one of the driven wheels tends to sping during a high speed driving, so that the engine torque can be reduced. Thus, according to the above described prior art, the braking control mode and the torque control mode are independently performed based on the behavior of the driven wheels.
It is generally known that the response to a control of the braking force is remarkably faster than that of the engine torque. Accordingly, it is desired that the control of the wheel spin by the application of the braking force to the driven wheels is to be effected not only for minimizing the unbalanced condition of the driven wheels, but also for a case when both the left-hand and right-hand driven wheels tend to spin. In the latter case, the braking force should be applied for a length of time required for reducing the torque of the engine, in response to the control under the torque control mode, to a level low enough to alleviate the excessive wheel spin.
However, the control of the wheel spin by the application of the braking force results in the consumption of extra energy for forcibly suppressing the engine. If the system is so arranged as to release the braking control mode as early as possible through a gradual change from the braking control mode to the torque control mode such that the braking control mode is superseded by the torque control mode, the excessive wheel spin could be reduced with less engine power loss. According to the above described prior art, however, the braking control mode and the torque control mode are carried out independently of each other and, therefore, it has been extremely difficult to establish a control system by which the excessive wheel spin can be obviated in dependence on both the braking force and the engine turque.
SUMMARY OF THE INVENTION
Therefore, the present invention has for its essential object to provide an improved automotive wheel spin control operable to control both the braking force, delivered to the driven wheel, and the engine torque, thereby to quickly and effectively minimize the spinning of the driven wheel of an automotive vehicle which would occur, during, for example, the start or acceleration of the automotive vehicle.
According to one feature of the present invention, the braking control is effected based only on the behavior of the driven wheels, so as to relieve the wheel spin to a proper value regardless of whether only one of the left-hand and right-hand driven wheels tends to spin or whether both of them tend to spin.
On the other hand, the torque control is performed in connection with the result of the braking control. In other words, in carrying out the torque control, the magnitude of the braking force produced during the braking control mode is measured or inferred and the engine torque is then controlled by an amount corresponding to the measured or inferred value. It is preferable that while the torque control is performed, reference is made to the behavior of the driven wheels. When the engine torque actually decreases according to the dynamic characteristic of the engine, the excessive wheel spin will be relieved in a quantity corresponding to the reduction of the engine torque. Then, the braking control acts to reduce the braking force, allowing the torque control to supersede the braking control.
In a preferred embodiment of the present invention, a smaller one of the two braking forces applied to the respective left-hand and right-hand driven wheels is used as the measured or inferred value to supersede the braking control with the torque control.
According to the prior art, when the braking force is controlled to a certain magnitude to reduce the excessive wheel spin to an optimum spin so as to produce the maximum traction, such a braking force is maintained at the same magnitude. In such a case, since the torque control is carried out in reference to only the behavior of the driven wheels, no control necessary to permit the torque control to supersede the braking control can be effected.
In contrast thereto, according to the present invention, since the torque control is effected in dependence on the braking control, the braking force once applied for the purpose of reducing the excessive wheel spin is progressively reduced to permit the torque control to supersede the braking control. As a consequence, the wheel spin can be controlled to an optimum value at which the traction can be maximized.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will become readily understood from the following description taken in conjunction with preferred embodiments thereof with reference to the accompanying drawings, in which:
FIG. 1 is a schematic circuit block diagram showing an automotive wheel spin control apparatus according to a first preferred embodiment of the present invention;
FIG. 2 shows graphs each illustrating the manner in which the excessive wheel spin is alleviated;
FIG. 3 is a diagram similar to FIG. 1, but showing another preferred embodiment of the present invention;
FIGS. 4 and 5 are graphs showing characteristics of a braking controller used in the apparatus; and
FIG. 6 is a graph showing characteristics of a brake actuator used in the apparatus.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Before the description of the present invention proceeds, it is to be noted that like parts are designated by like reference numerals or characters. It is also to be noted that, in describing the present invention, reference is made to an automotive vehicle having a pair of front non-driven wheels and a pair of rear driven wheels.
Referring now to FIG. 1, a wheel spin control apparatus shown therein comprises first and second driven wheel speed sensors VD L and VD R for detecting, and generating output signals indicative of, the speeds of rotation of the left-hand and right-hand driven wheels, respectively; first and second non-driven wheel speed sensors VN L and VN R for detecting and generating output signals indicative of, the speeds of rotation of the left-hand and right-hand non-driven wheels, respectively; first and second spin output units S L and S R , each operable to generate a respective spin signal indicative of the amount of spin occurring in the associated driven wheel; and first and second braking controllers BC L and BC R . Each of the first and second braking controllers BC L and BC R is so designed and so operable as to generate a respective first command required to apply or increase the braking force to be applied to an associated wheel brake unit B L or B R through an associated brake actuator BA L and BA R in the event that the excessively large wheel spin has taken place or is likely to occur and also to generate a respective second command required to reduce or remove the braking force in the event that the wheel spin has become excessively small or is likely to become excessively small.
Each of the brake actuators BA L and BA R is operable in response to the first command from the associated brake controller BC L and BC R to increase the braking force to be applied to the associated brake unit B L or B R and, in response to the second command from the same brake controller BC L or BC R , to decrease the braking force applied to the associated brake unit B L or B R .
Each of the spin output units S L and S R may be employed in the form of a subtracter operable to calculate a difference in level between the outputs from the wheel speed sensors VD L and VN L or between VD R and VN R , that is, the difference between the speed of rotation of the left-hand driven wheel and that of the left-hand non-driven wheel, or between the speed of rotation of the right-hand driven wheel and that of the right-hand non-driven wheel.
It is to be noted that, although the amount of the wheel spin can be indicated by the difference between the speed of rotation of each of the driven wheels and the vehicle speed (an average value between the speeds of rotation of the left-hand and right-hand non-driven wheels), it is desirable to effect a correction to the amount of wheel spin particularly during the cornering of the automotive vehicle. To this end, the differnece in speed of rotation between the left-hand and right-hand non-driven wheels, or between the right-hand driven wheels and the right-hand non-driven wheels, may be used as a parameter representative of the amount of cornering error. A method of effecting such correction during the cornering of the automotive vehicle is disclosed, for example, in Japanese Patent Application No. 60-201233, filed on Sept. 11, 1985, by the same assignee as the present application.
The wheel spin control apparatus also comprises first and second pressure sensors P L and P R , the first pressure sensor P L being operable to detect and generate a first pressure signal indicative of the magnitude of the braking force exerted by the first brake actuator BA L on the left-hand driven wheel through the brake unit B L . The second pressure sensor P R is operable to detect and generate a second pressure signal indicative of the magnitude of the braking force exerted by the second brake actuator BA R on the right-hand driven wheel through the brake unit B R . The first and second pressure signals emerging from the first and second pressure sensors P L and P R , respectively, are applied to a selector L which compares the first and second pressure signals with each other and applies to a torque controller EC one of the first and second pressure signals which is lower in level than the other of the first and second pressure signals.
The torque controller EC is so arranged to operate in response to the output from the selector L to generate a command necessary to cause an engine actuator EA to increase or decrease the engine torque depending on the signal delivered by the output from the selector L.
While the wheel spin control apparatus according to the first preferred embodiment of the present invention is so constructed as hereinbefore described, the present invention is generally featured in that the control performed by the torque controller EC depends on the first and second pressure signals from the first and second pressure sensors P L and P R , not on the outputs from the first and second wheel spin output units S L and S R .
Next, the operation of the wheel spin control apparatus described above will now be described with reference to FIG. 2, graphs (a) and (b).
It is now assumed that the automotive vehicle stands still with the left-hand and right-hand driven wheels resting, respectively, on a slippery surface and a normal surface of a roadway. The slippery road surface may be an iced road surface, a snow-covered road surface or a sand-covered road surface and is generally characterized by a relatively low μ(a coefficient of friction relative to the tire and road surface), whereas the normal surface is characterized by a relatively high μ. When a driver of the automotive vehicle depresses an accelerator pedal, both of the driven wheels undergo a moderate spin and the vehicle starts its movement with accelerated velocity appropriate to the slippery road surface. The behavior of the right- and left-hand driven wheels during this condition are illustrated in FIG. 2, graphs (a) and (b), respectively.
It is assumed that the engine torque transmitted to the left-hand driven wheel for a given amount of depression of the accelerator pedal in the automotive vehicle has a power of 10. Similarly, the engine torque transmitted to the right-hand driven wheel has a power of 10. In this case, the left-hand driven wheel on the slippery road surface would move the vehicle with a force (referred to as an effective force) of 3 and would undergo a spinning with a force (referred to as an excessive force) of 7, as shown in FIG. 2, graph (b). On the other hand, the right-hand driven wheel on the normal road surface would move the vehicle with an effective force of 6 and would undergo a spinning with an excessive force of 4, as shown in FIG. 2, graph (a). This is particularly true where the left-hand and right-hand driven wheels are not coupled directly together.
However, since the automotive vehicles usually have a differential gear unit through which the engine torque is distributed to both the left-hand and right-hand driven wheels, the greater effective force of the two driven wheels would be reduced to be equal to the smaller effective force. Therefore, the effective force of the right-hand driven wheel, which ought to be 6, is limited to 3 and the remaining force of 3 would be transmitted through the differential gear unit to the left-hand driven wheel thereby to promote the further spinning of the left-hand driven wheel. Such wheel spins are detected by the respective spin output units S L and S R . Immediately after the detection by the wheel spins occurring in the left-hand and right-hand driven wheels, the braking controller BC L and BC R generate respective output signals which are in turn applied to the associated brake actuators BA L and BA R to bring the latter into operation. Accordingly, through the brake units B L and B R , a braking force of 4 and a braking force of 7 are applied to the right-hand driven wheel and the left-hand driven wheel, respectively, so that the excessive wheel spins occurring in the left-hand and right-hand driven wheels can be alleviated in a short time. During this process, the effective propulsive force of the right-hand driven wheel increases relatively to the increase of the braking force applied to the left-hand driven wheel. When the braking force applied to the left-hand driven wheel attains 3, the right-hand driven wheel could exhibit a propulsive force of 6 appropriate to the friction coefficient μ of the road surface.
The braking force applied to the associated right-hand and left-hand driven wheels are detected by the pressure sensors P R and P L which subsequently provides the second and first pressure signals, respectively, said second pressure signal being indicative of the amount of the braking force applied to the right-hand driven wheel and the first pressure signal indicative of the amount of the braking force applied to the left-hand driven wheel.
The first and second pressure signals emerging from the first and second pressure sensors P L and P R , respectively, are applied to the selector L which compares the first and second pressure signals with each other and selects a lower one of the first and second pressure signals, that is, the second pressure signal in the illustrated instance. The selected pressure signal is applied to the torque controller EC, which, is response to the output from the selector L, generates a command necessary to cause the engine actuator EA to decrease the engine torque. Thus, even though the amount of the depression of the accelerator pedal does not change, the engine torque can be reduced accompanied by the reduction of the wheel spins occurring in the left-hand and right-hand driven wheels, thereby to permit the braking forces to be lowered. The reduction of the engine torque is progressively continued so long as the selector L provides the second pressure signal to the torque controller.
Then, when the selector L no longer produces a pressure signal, the control of the excessive spin occurring in the left-hand driven wheel is based on the control of both the engine torque and the braking force whereas the control of the excessive wheel spin occurring in the right-hand driven wheel is based only on the control of the engine torque.
Thus, according to the present invention, in the event of the occurrence of the excessive wheel spin, the excessive wheel spin can be immediately suppressed or alleviated by the braking force and the engine torque is subsequently reduced, accompanied by the lowering of the braking force. Therefore, it is possible to suppress the excessive wheel spin as quickly as possible and to permit the control of the engine torque to supersede the control of the braking force, thereby to minimize an unnecessary loss of the engine torque.
It is to be noted that, although each of the first and second spin output units, the first and second braking controllers, the selector and the torque controller, all included in a circuit represented by the chain-lined block, may comprise hardware such as shown, a programmable microcomputer may be employed in combination with a software programmed so as to perform a function similar to that done by the circuit represented by the chain-lined block.
The wheel spin control apparatus according to another preferred embodiment of the present invention is shown in FIG. 3. The embodiment shown in FIG. 3 differs from that shown in FIG. 1 in that, instead of measuring the braking forces by the pressure sensors, the second embodiment employs calculators GP R and GP L to calculate braking forces based on the outputs from the braking controllers BC R and BC L , respectively, in consideration of the operating characteristics of the associated brake actuators BA L and BA R . In other words, according to the second embodiment, the braking forces are inferred. Furthermore, the embodiment shown in FIG. 3 differs from that shown in FIG. 1 in that the engine controller EC is divided into a portion ECB which governs the engine control based on the braking force and a portion ECS which governs the engine control based on the behavior of the driven wheels.
The inference of the braking force would reduce the accuracy of operation of the brake actuator BA in a quantity which corresponds to the deviation, and would result in the rough engine torque control. However, such a rough engine torque control will eventually reflect upon the behavior of the driven wheels and can be fed back to the amount of control of the braking force and, therefore, the control will not be extremely deteriorated. Since a device for measuring the braking force or its equivalent braking pressure will result in the increase of the manufacturing cost of the apparatus, the system of inference, which can be embodied by the addition of software, should be attractive.
As will become apparent from the description hereinbelow, it is preferable to have the torque controller EC to receive not only the information representing the braking force which is to be superseded but also information representing the engine torque to be reduced in relation to the speed of rotation of the driven wheels.
The necessity to supersede the braking force is because the dynamic characteristic of the torque control of the engine is slow. Accordingly, in the event of an occurrence of an abrupt increase of the excessive wheel spin, it is desirable that the control with the braking force is first carried out temporarily, followed by the control with the engine torque gradually taking over the control with the braking force. However, under conditions in which the amount of the wheel spin slowly increases from a moderate value to an excessive value, or in which the amount of the wheel spin is within the upper limit of the appropriate range, but stays close to the upper limit for a long period of time, the control should preferably be done only by the engine torque control which is slow in response. Otherwise, if the control is done in combination with the braking force control, there may be undesirable shock which would be imposed on the vehicle when the control with the braking force is introduced. Therefore, under the condition described above, it appears to be feasible to control the engine torque reduction directly in connection with the speed of rotation of the driven wheels. In general, the braking controller BC is preferred to be carried out for controlling a relatively fast change of the spin, and the engine torque control by ECS is preferred to be carried out for controlling a relatively slow change of the spin.
The details of the braking controller BC will now be described.
Assuming that the amount of the spin occurring in one of the driven wheels is S 1 and the optimum amount of spin is S 0 , the excessive amount X 1 of spin occurring in such one of the driven wheels can be expressed by the following equation.
X.sub.1 =S.sub.1 -S.sub.0
It is, however, to be noted that the optimum amount S 0 is not fixed, but may take a value generally intermediate between a certain fixed value and a value proportional to the vehicle speed (VN 1 +VN 2 )/2 and will approach the fixed value at low speed and the value proportional to the vehicle speed at high speed. By way of example, the optimum value S 0 can be expressed by the following equation.
S.sub.0 =a+b·(VN.sub.1 +VN.sub.2)/2
The braking controller BC generates from its output terminal three different signals, that is, "+1", "0" and "-1" signals, as shown in FIG. 4, graph (a). During a period in which the braking controller BC generates the "+1" signal, the fluid pressure in a braking system is increased by a solenoid (not shown) provided in the brake actuator BA to increase the braking force being applied to the associated driven wheel. During a period in which the braking controller BC generates the "0" signal, the fluid pressure is maintained, but during a period in which the braking controller BC generates the "-1" signal, the fluid pressure is reduced to lower the braking force being applied to the associated driven wheel.
The manner in which the signals are processed in the braking controller BC will now be described. After the calculation of the amount of excessive spin X 1 as hereinbefore described, the possibility of occurrence of the wheel spin is examined by using the follow equation Y 1 which includes a differential dX 1 /dt of X 1 with time.
Y.sub.1 =kX.sub.1 +k'(dX.sub.1 /dt)
When the amount of excessive spin X 1 is changed as shown in FIG. 5, waveform (a), Y 1 changes in a manner shown in FIG. 5, waveform (b). As apparent to those skilled in the art, a peak of Y 1 appears before the excessive spin amount X 1 attains a peak, because the equation Y 1 contains the differential of X 1 . Thus, by detecting the peak of Y 1 , it is possible to detect a moment when the wheel spin is likely to occur. When Y 1 and two threshold values T 1 and T 2 are compared and when Y 1 exceeds the threshold value T 1 in a positive direction, or when Y 1 exceeds the threshold value T 2 in a negative direction, the braking controller BC generates the "+1" and "-1" signals as shown in FIG. 5, waveform (c). According to one arrangement, the "+1" and "-1" signals can be maintained during when Y 1 exceeds the threshold values T 1 and T 2 . According to another arrangement, the "+1" and "-1" signals are terminated when Y 1 attains a peak point in the positive or negative direction. The latter arrangement is preferable because any possible overshooting can be avoided and a smooth reduction of the wheel spin can be achieved.
During, a period in which neither of the "+1" or "-1" signals is generated, the "0" signal, that is, a hold command, is generated accompanying short pulses of "-1" to effect a moderate reduction of the fluid pressure. This can be accomplished by combining the "-1" signal in the "0" signal in an appropriate spacing. After the command to effect the moderate reduction of the fluid pressure is continued for a predetermined time, the brake fluid pressure is reduced completely to zero, thereby completing the control.
FIG. 5, waveform (d) illustrates a change in braking fluid pressure controlled by the signal shown in FIG. 5, waveform (c).
It is to be noted that the operating characteristic of the brake actuator BA is such that the fluid pressure P will not be reduced lower than zero even when the reduction command "-1" is continuously generated. In other words, the brake actuator BA has such an operating characteristic that P will not become smaller than 0.
In order to accomplish a shift from the braking control mode to the torque control mode at a moderate speed, the frequency of the pulse "-1" within "0" to effect the moderate reduction as hereinbefore described is preferably selected in consideration of the structure of the torque controller and the constants used therein.
The details of the torque controller EC will now be described. It is to be noted that the torque controller EC shown in FIG. 1 has the same structure as ECB shown in FIG. 3.
It is now assumed that the amount of the engine torque to be reduced is E. In order to quickly take over the braking control by the engine control at an amount corresponding to the excessive wheel spin having been temporarily reduced by the control of the braking force applied to the driven wheel, it is necessary to apply a signal to the torque controller so as to make dE/dt depend on the pressure P. For this purpose, it is preferable to control the system to satisfy dE/dt proportional to P. Of course, it is possible to introduce, not a simple proportional relationship, but a suitable functional relationship. When the value of P is zero or substantially zero, or when this condition continues at least to a certain extent, dE/dt should be controlled not equal to zero, but equal to a small negative value; and absolute value of which increases gradually. This is an idea similar to that for gradually reducing the braking pressure by the command applied to the braking controller BC.
The parameter P representing the brake pressure herein used may be either the measured value or the inferred value as hereinbefore described. Where P is inferred, the inferred value and a value dP/dt of the pressure increased per unit of time is used.
The brake actuator BA may have such an operating characteristic that, depending on the pressure P currently used, dP/dt may vary even when the brake actuator BA receives the same "1" or "-1" signal from the braking controller BC. For example, a case in which the brake actuator BA has received the "+1" command is illustrated in FIG. 6. In such a case, instead of employing the inferred value of P=(dP/dt)∫Zdt with a presumption that dP/dt is a constant value and employing a command value Z (a type of integer which is either one of "+1", "0" or "-1" on a time-series basis), it is preferable to employ the following equation.
Pi=P.sub.i-1 +(dP/dt)·Δt
In this case, dP/dt is not a constant value and represents the speed of change of the braking pressure determined by the command Z and pressure P, and Δt represents a unit of time during which the command Z continues.
The pattern of an output from the torque controller EC depends greatly on what is used for the engine actuator EA. In the case where the engine actuator EA is a type which responds to any one of the "+1", "0" and "-1" signals as similar to the braking actuator BA, the pattern of the output signal from torque controller EC would preferably be a pulse having a controlled pulse with or a controlled pulse density, as shown in FIG. 5, waveform (c).
On the other hand, in the case where the engine actuator EA is a pulse motor of a type wherein the speed can be specified in terms of the pulse rate from outside, the torque controller EC may output dE/dt without modifying it.
The details of ECS will be hereinafter described. One of the characteristic features of ECS lies in that, in contrast to the braking controller BC which controls each of the driven wheels, it controls the engine torque, produced by the automotive engine, in relationship to the smaller one of the wheel spins occurring in the respective driven wheels. As hereinbefore described, it is desirable that ECS is so designed as to be capable of detecting a moderate change as compared with that of the braking controller BC.
Accordingly, in the braking controller BC the differential term plays an important role, but the indifferential term in ECS is of secondary importance. Instead, ECS plays an important role if it has an integrating element, that is, an element for detecting a condition in which a relatively large wheel spin continues for a certain length of time. For this purpose, by rendering a smaller one of S 1 and S 2 to be SL, and rendering a time in which the excessive spin XL=SA-S0 is maintained positive to be T, the following function;
YE=kE·XL+kE'(dXL/dt)+kE"·T
may be prepared for the comparison with the threshold value. Also, S 0 for the braking controller BC and S 0 for ECS can be changed.
If XL is maintained in a negative region as similar to the case with the braking controller BC, E is moderately reduced. In other words, it is necessary to reduce the rate of reduction of the engine power output to rapidly follow the control ordered by the manual operation.
Also, even though the engine actuator EA continues generating a command in which dE/dt is megative as is the case with the brake actuator BA, it is necessary for the engine actuator EA to have such a characteristic that E will not become negative (in which condition the engine torque greater than the produced during the manual operation is produced) after E becomes zero, so that the engine will not produce more power than the manually commanded power.
In the case of the type wherein dE/dt can be inputted as a continuous value as a method of inputting ECB and ECS to the engine actuator EA, it is possible to add respective outputs from ECB and ECS together and apply it to the engine actuator EA.
Where the engine actuator EA is of a type capable of responding to any one of the "+1", "0" and "-1" signals, although it is possible to add the respective outputs from ECB and ECS together and apply it to the engine actuator EA, it is also possible to effect such an addition at a stage preceding the conversion into a pulse width or a pulse density of "+1", "0" and "-1".
Furthermore, it is possible to construct a switching output such that ECB can be outputted when P is a value greater than a certain value, but ECS can be outputted when P is a value smaller than the certain value.
From the foregoing full description of the present invention, it has now become clear that, the present invention is such that the excessive wheel spin is once reduced by controlling the braking force which has a quick response and then controlling the engine torque which has a slow response. Accordingly, by allowing the engine torque control to supersede the braking control, the excessive wheel spin can be quickly alleviated and, at the same time, any possible damage to or loss of energy of various component parts of the automobile power system which would be brought about at the unnecessary braking control can be advantageously avoided.
It is to be noted that the contents of the braking controller BC and the torque controller EC hereinabove described are only for the purpose of illustration and may be varied in any way without departing from the spirit and scope of the present invention.
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A wheel spin control apparatus for use in an automotive vehicle having left- and right-hand driven wheels includes spin detectors for detecting the occurrence of an excessive wheel spin in the left- and right-hand driven wheels, and braking controllers for applying braking forces to the left- and right-hand driven wheels in response to the detection of the excessive wheel spins to suppress the excessive wheel spin, and thereafter gradually weakening the braking forces. The wheel spin control apparatus further includes a torque controller for controlling an output power of an engine employed to drive the left- and right-hand driven wheels such that the engine output power is gradually decreased as at least one of the braking forces is gradually weakened, whereby the suppression of the driven wheel effected by the braking controller is gradually taken over or superseded by the torque controller.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to compacted towels formed of hydroentangled or spunlace nonwoven fabric. More particularly, the present invention relates to compacted towels that have surface textures that recover following compaction and wetting and that have improved strength and wear characteristics due to being formed in both a machine direction and a cross lapping direction.
2. Description of the Related Art
Compact towels have been formed by spunlace techniques. The towels have included single direction webs (i.e., fibers arranged in the machine direction). The webs are hydroentangled by running web formed by carding the fibers into a single direction sheet and then subsequently passing the sheet under water jets to entangle the fibers. The resulting material is nonwoven and, in currently available compact towels, the material exhibits low resistance to tearing in the machine-direction (i.e., a direction perpendicular to the cross machine direction).
This single direction material is less than desirable because it easily comes apart when used as a towel. This single direction material also cannot be cut to be a exact size because one side is stronger than the other which leads to dimensional instability under stress.
SUMMARY OF THE INVENTION
Accordingly, a stronger biodegradable nonwoven towel is desired that can be compressed into a compacted towel, or cake, and that can recover with respect to dimensions and textures when the compacted towel is expanded for use. In some configurations, a compacted nonwoven can be prepared that, when reconstituted with water from a compressed state, produces a wipe, towel, cleaning cloth, or the like. The fabric can have substantially balanced machine direction/cross direction properties, a weight of between about 30 and about 120 GSM, at least one surface with a mild abrasive property, and a composition that includes cellulosic fiber for good compaction and water holding properties. In some configurations, the fabric can be a textured spunlace fabric but any composition from 50/50 rayon/PET to 100% cellulosic would be acceptable. In some configurations, the fabric can be a thermobond fabric with a high rayon content in a blend with a thermoplastic fiber that bonds the structure with heat and pressure. In some other configurations, the fabric can be a thermobond airlay pulp sheet with embossing for surface texture. Such a fabric may require a large amount of bonding fiber in order to recover from compression. In yet other configurations, the fabric can comprise needle punch and print bond nonwovens.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects and advantages of the present invention will now be described with reference to the drawings of a preferred embodiment, which embodiment is intended to illustrate and not to limit the invention.
FIG. 1 is a top plan view of a towel that is arranged and configured in accordance with certain features, aspects and advantages of the present invention.
FIG. 2 is a simplified section view of the towel of FIG. 1 .
FIG. 3 is a perspective view of a compacted cake.
FIG. 4 is a flow chart of a manufacturing process.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a towel 100 that is arranged and configured in accordance with certain features, aspects and advantages of the present invention. The towel 100 can be formed of a spunlace or hydroentangled nonwoven fabric.
Advantageously, the towel 100 comprises a surface texture comprising a plurality of bumps, nubs, or other surface relief features 102 . In some configurations, the plurality of bumps, nubs, or other surface relief features 102 can form a repeating pattern. Other configurations are possible. The bumps, nubs or other surface relief features 102 , which can include apertures, advantageously create reservoirs or channels to contain dirt during scrubbing. Thus, such features 102 improve the scrubbing properties of the towel 100 .
The towel 100 can be formed in any suitable manner. In some configurations, the towel 100 is formed of cellulous fibers. Preferably, the fibers used are selected from the group consisting of rayon, tencel, cotton and wood pulp, bleached cotton, a corn-based polymer (e.g., PLA or poly-lactic-acid), linen, flax, hemp, jute, and polyester fiber from recycled bottles. More prefereably, the fibers used are selected from the group consisting of rayon, tencel, and bleached cotton. In some configurations, the fibers are a blend of one or more of the above-mentioned fibers.
The towel 100 can be formed of 100% rayon or of a blend that features low levels of polyester. For example, in some configurations, a 70/30 rayon and polyethylene terephthalate (PET) blend can be used with a weight of about 1.75 ounces per square yard. In such configurations, the fibers preferably are formed into an isotropic web and the web is not carded. In some configurations, a blend of rayon and PET can be used with a weight of about 2.0 ounces per square yard. In such configurations, the fibers preferably form an isotropic web. In yet other configurations, a 50/50 blend of rayon and PET with a weight of about 2.0 ounces per square yard can be used. The resulting fabric can have a pattern of apertures or the like that are formed in 8 inch by 8 inch, 12 inch by 12 inch or 16 inch by 16 inch repeating patterns. In such configurations, the fibers preferably form an isotropic web with a substantially 5% finish. In some such configurations, bico fiber in the range of about 7% to about 10% can be used to enhance toughness and abrasion resistance. In some configurations, a blend of 60/40 pulp and PET can be used.
Preferably, the use of polyester is limited in forming the fabric for the towel 100 because, as will be discussed, the towel 100 is designed for compaction and biodegradability and polyester resists compaction and biodegrading. With that said, it is possible to form the towel of a material comprising up to about 40-50% PET fiber content. It is believed that this level of PET fiber content may not impair compaction in a significant enough manner to be unworkable. Nevertheless, in some configurations, biodegradability is desired. Accordingly, the towel 100 preferably is formed of 100% rayon to provide a compactable and biodegradable product. Other suitable blends also can be used keeping in mind a desire for biodegradability, good strength characteristics in both the machine direction and the cross direction and a desire for resilient texturing that can recover following compression and compaction into a compacted towel, as will be discussed.
Any suitable process can be used for fabric used for formation of fabric used for the towel 100 . One process is shown in the flow chart of FIG. 4 . In some configurations, the fibers are dry mixed in a hopper. The fibers are distributed to define a web that will form the fabric used to make the towel 100 . S- 1 . To distribute the fibers, the fibers can be fed through a card. Generally speaking, the card uses wire to comb the fibers out so that the fibers are all pointing in a first direction (e.g., east and west). The fibers in the first direction are then combined with fibers that are arranged in a second direction (e.g., north and south). Other manners also can be used to attain an isotropic web of fibers or a random or cross laid formation of the fibers. Web formation has been found to play a major role in strength of the towel 100 once compressed (i.e., cake strength) and in wipe dimensional stability after recovery from the compressed state. An isotropic, random or cross laid formation is believed to be far superior to a single direction carded web in both cake strength and wipe stability.
As used herein, the weight per unit of size (e.g., ounces per square yard or grams per square meter) is determined in part by how many layers of fibers are combined. In other words, more layers result in larger weights per unit of size.
By arranging the fibers to form an isotropic web, the resulting fabric can have improved strength characteristics in both the machine direction as well as the cross direction. As used herein, “machine direction” refers to the direction that the fibers travel as the fabric is produced. Also, as used herein, “cross direction” refers to a direction generally perpendicular to the direction that the fibers travel as the fabric is produced.
The web can be passed under high pressure water jets. See S- 2 . In some configurations, the web is subjected to multiple rows of very fine water jets coming from a manifold at a pressure of between about 1000 psi and about 6000 psi. In some embodiments, the water jets spray water at about 2000 psi to about 4000 psi manifold pressure. The water jets impact the web, which is supported on a very fine mesh support. The water jets cause entanglement of the fibers and form the fabric for the towel 100 . The entangled fabric thereby obtains good strength and dimensional stability.
The mesh support can be a very fine screen material or the like. The mesh support defines a porous screen. To create the bumps, nubs, apertures or other surface relief features 102 , the mesh support can be modified. For example, because the fibers are entangled on the surface of the support, creating a surface texture on the surface of the support can lead to creation of bumps, nubs and other surface relief features due to movement of the fibers during entanglement. Thus, the bumps, nubs, basket weave or other surface relief (e.g., overall engineered print, which uses surface relief features that are all about the same in a single material) preferably are created during entanglement on a modified porous screen.
One way to create the desired surface relief is to impart onto the surface of the screen a desired pattern (e.g., pyramids or other surface textures). Another way to create the desired surface relief is to create a negative by embossing on the screen directly which creates a pattern in the material of the screen itself. With a patterned screen, during the hydroentanglement, the fibers move into the valleys defined between the peaks on the screen. Thus, the fabric develops thicker regions in the regions of the valleys on the screen.
While the fabric can be formed with surface relief using the patterned screen, the surface relief is difficult to develop in very light fabrics (e.g., less than about 30 grams per square meter). In some configurations, the fabric has a weight within the range of about 30 grams per square meter to about 120 grams per square meter. Better results (e.g., texturing, compaction and recovery) are believe to be obtained forming fabrics in the about 60 to about 90 grams per square meter range. More preferably, fabrics can formed in the range of about 45 to about 65 grams per square meter. In one preferred embodiment, the fabric can have a weight of about 60 grams per square meter. Even more preferably, the fabric can have a weight of about 60 grams per square meter with a difference about +/−six percent. Fabric weights above about 90 grams per square meter are believed to make difficult the necessary movement of the fibers to form durable nubs.
Patterns and textures imparted to a nonwoven material during the entanglement process are believed to be greatly more recoverable after compaction than patterns and textures imparted by embossing following entanglement. This is believed to result because forming the relief pattern during the entanglement process causes the fibers to move to form the relief pattern. Thus, the fiber to fiber bonds are established within the relief pattern. Preferably, the energy level of the jets performing the entanglement is sufficient to work fully through the material so that a desired level of entanglement occurs throughout the thickness of the surface relief.
Once the spunlace fabric is formed, the fabric is dewatered. See S- 3 . Any suitable dewatering technique can be used. In some configurations, the water can be squeezed from the fabric between rubber rolls. Squeezing the fabric is believed to cause a water reduction to about 300%. A vacuum roll or vacuum slot can be used to further reduce the water content to about 175%. Finally, heat and air (e.g., steam cans, ovens, high velocity air jets) can be used to get the water content down to about 5%, which is about the expected water content in 100% rayon sheets, for example.
In some configurations, a squeeze roll water extractor/finish applicator can be used to apply a finish to the fabric that could include polish, cleaner, lemon scent, soap, shampoo, color, or other active ingredients. As discussed directly above, in some configurations, a water extractor may be used and, in such embodiments, some type of finish applicator such as a spray prior to the squeeze rolls can be used to add any desired additives such as those mentioned above. Finish can be a component in many types of wipes and towels. Desirably, any additive is selected to not retard the compaction efficiency or to not harm the integrity of the compacted product.
With the fabric made, the fabric can be cut into sheets usable for towels or other end products. See S- 4 . The fabric can be cut into the desired size using any commonly recognized machines, such as a Hudson-Sharpe or Gerber. In some configurations, the towel 100 can have a length of about 15 inches and a width of about 15 inches. In other configurations, the towel 100 can have a length of about 11 inches and a width of about 8.5 inches. Preferably, the length of about 11 inches and the width of about 8.5 inches varies by as little as about 0.4 centimeters. Advantageously, the towel 100 can have a width of about 8.5 inches, which allows the full fabric width to be utilized because the fabric has a width of about 154 cm or about 61 inches. Thus, seven pieces can be formed across the width of the material with a minimal amount of about 1.5 inches left over depending upon the tolerances held during cutting. Of course other dimensions are possible. Moreover, machines currently used to manufacture spunlace fabrics range in width from about 50 inches to about 200 inches. In addition, the output from these machines can be adjusted within several inches of the nominal width for the machine.
Sheet size is a consideration for various wiping products with several ranges desired for most end uses. A sheet size of around 100 square inches is desired for a personnel care wipe, while a sheet size of around 400 square inches is desired for a spa towel and a larger size may be required for certain cleaning/polishing applications. The balanced web properties achieved with the fabric described herein allow for either dimension of the fabric to be used as the machine direction of the fabric. In other words, because the fabric is dimensionally stable in both directions (i.e., machine direction and cross direction) and because the fabric has improved strength characteristics, it is possible to orient the towels or other wiping products in either direction of the fabric without concern for the reduced strength and dimensional stability exhibited in prior products.
With the fabric sheets cut into the towels 100 , the towels 100 are ready for compacting into cakes 104 . Generally speaking, the size and weight of the fabric will determine how small a compacted product can be produced
The diameter of the cake preferably is selected based either on the weight and size of the towel 100 or some safety or marketing need. For example, for a large heavy towel, a large diameter is used to keep the compacted product from becoming too bulky which can harm the integrity of the compacted cake. In the case of a baby wipe, a small diameter might be acceptable, but a choking risk can dictate a larger diameter per CPSC regulations.
With a desired diameter determined, the cut towel 100 is folded into a suitable form for compression into a compact cake of the diameter, thickness, and density desired. See S- 5 . For instance, if the towel is 10 inches wide by 10 inches long and a cake is desired that is 1.5 inches in diameter, it may be best to fold the towel into something no more than 1.5 inches wide with the corners being tucked under. In some configurations, the folded towel can be formed into a roll (e.g., spiral) before being inserted into the compaction device. In some configurations, the towel 100 is folded by picking up the towel in a central portion such that the edges of the towel hang downward in a conical or centrally tented shape. In other words, when picked up, the towel resembles an upside down ice cream cone.
Preferably, the cake has a diameter of between about 1.5 inches and about 2.5 inches. In some configurations, the cake has a diameter of about 4.5 centimeters with a thickness of about 0.32 centimeters. Preferably, in such configurations, the diameter with vary less than about 0.3 centimeters. In some configurations, the cake has a diameter of about 1.75 inches. Preferably, the cake has a thickness of between about 0.5 inch and about 0.125 inch. In some configurations, the cake has a thickness of about 0.125 inch. Other sizes are possible. In some other configurations, the cake formed from a towel that has a length of about 11 inches and a width of about 8.5 inches has a diameter of about 1.75 inches, a thickness of about 0.125 inch and a density of about 0.857 grams per cubic centimeter. In yet other configurations, the cake formed from a towel that has a length of about 25 inches and a width of about 16 inches has a diameter of about 1.75 inches, a thickness of about 0.5 inch and a density of about 0.890 grams per cubic centimeter.
The folded towel can be compacted using any suitable compacting process. See S- 6 . In some configurations, the compacting process is that described in U.S. Pat. No. 4,241,007, which was issued to Mitsubishi Rayon Co. on Dec. 23, 1980, which is hereby incorporated by reference in its entirety. In some configurations, the towels 100 are formed within a 1.75 inch diameter cylinder/piston device where the dry prefolded spunlace nonwoven fabric is compressed under a force of about 1100 kilograms per square centimeter to about 1500 kilograms per square centimeter. In some configurations, the fold pattern used to prepare the wipe for compaction is important to achieving a smooth surface compacted product and also to ease the recovery of the wipe when wet. Typically, the desired fold pattern will vary with the size of the towel and the desired size and density of the resulting cake and the shape of the finished product. In the configurations such as those described above where the towel is simply picked up to be folded, the towel can be loaded into a compacting machine by introducing first the lower portion of the towel into a funnel-shaped opening of the compacting machine. Once positioned in the compacting machine, the compacting machine compresses the towels 100 into the cakes.
The weight (i.e., the grams per square centimeter) of the towel also can impact the function of the towel and how well it will compact. Heavier weight towels will allow a smaller wipe size that can still be effective and that can reduce cost but if the towel is too heavy, the integrity of the compacted cake can be adversely impacted.
During or after compacting of the towel, the compacted cake can be embossed with identifying characteristics. For example, the compacted cake can be embossed with a logo during the compression of the towel into the cake configuration. Preferably, the cake is compressed to a density of between about 0.647 grams per cubic centimeter and about 0.778 grams per cubic centimeter. More preferably, the cake is compressed to a density of between about 0.840 grams per cubic centimeter and about 0.900 grams per cubic centimeter. Even more preferably, the cake is compressed to a density of between about 0.850 grams per cubic centimeter and about 0.890 grams per cubic centimeter. Embossing is a benefit of the process and a specific density of the cake can be important to obtaining a good level of definition in the embossed design. Density is the result of the compaction force and generally is within certain limits to produce a successfully compacted product. Some of these values are included in the Mitsubishi patent and others are higher due to the design of the wipe/towel.
Following compaction, the cakes preferably are wrapped into a cover. In some configurations, the cakes can be wrapped within a shrink wrap material. Preferably, at least a portion of the cakes is covered. For example, as shown in FIG. 4 , the protective covering can extend over the outer circumference and can wrap onto a portion of an upper surface and a lower surface. In such configurations, the upper surface and the lower surface of the cake preferably is covered by a paperboard material or the like. The paperboard material can be a disc-shaped advertisement or can contain a logo, barcode or other identifying information. In some configurations, the cake is completely enclosed within a protective covering.
In some configurations, the compactness of the cake depends at least in part upon the protective covering. The covering reduces the likelihood of undesired swelling during marketing or storage. For example, an unprotected towel in a humid environment can swell by as much as about 50% of its fully compacted size (e.g., compacted thickness may be 0.375 inch that swells to 0.5625 inch). In some embodiments, in an 80+% humidity environment, the unwrapped towel can grow as much as 33-100% over the course of a few days.
In some configurations, the cakes can be individually wrapped. In other configurations, the cakes can be wrapped together in multiples. For example, ten or more cakes can be stacked together and wrapped in a tube. In some configurations, a plurality of unwrapped cakes can be stored within a air tight or liquid impermeable zippered bag. Other manners of protecting or distributing the cakes also can be used. In some configurations, the weight of each compacted towel that is about 8.5 inches wide by about 11.5 inches long prior to compaction is about 3.62 grams. Preferably, the weight for such compacted towels is between about 3.2 grams and about 4 grams. More preferably, the weight for such compacted towels is between about 3.29 grams and about 3.96 grams.
To render the compacted towel useful, the cake is wet or immersed in water. As water is absorbed by the cake, the cake will expand and generally return to the shape and texture of the folded towel. Once the cake has expanded, the excess water can be squeezed from the towel and the towel can be unfolded for use.
In some configurations, towels can be made from 100% rayon. The weight can be about 75 grams per square meter with a range from about 50 grams per square meter to about 80 grams per square meter. The material can be formed in an entanglement pattern with a raised nub. The web formation can be cross-laid. The sizing can be about 8.5 inches by about 11 inches. The color can be natural without any additives added for a finish. The wipe can be compacted to a diameter of about 1.75 inches with a thickness of about 0.125 inch. The compacted towel can be embossed with a logo in some embodiments and can be unembossed in other embodiments.
In some configurations, a larger towel can be formed of 100% rayon. The weight can be about 60 grams per square meter. The material can be formed in an entanglement pattern with a raised nub. The web formation can be cross-laid. The sizing can be about 16 inches by about 25 inches. The color can be natural and no finish preferably is used. The towel can be compacted to a diameter of about 1.75 inches with a thickness of about 0.5 inch. The compacted towel can be embossed with a logo in some embodiments and can be unembossed in other embodiments. Preferably, the towel is enclosed in a plastic overwrap.
Although the present invention has been described in terms of a certain embodiment, other embodiments apparent to those of ordinary skill in the art also are within the scope of this invention. Thus, various changes and modifications may be made without departing from the spirit and scope of the invention. For instance, various components may be repositioned as desired. Moreover, not all of the features, aspects and advantages are necessarily required to practice the present invention. Accordingly, the scope of the present invention is intended to be defined only by the claims that follow.
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A towel is formed by hydro-entanglement of an isotropic web formed of predominantly rayon. The towel comprises a surface texture formed during hydroentangling. The towel is compacted into a cake or disk shape for distribution. The cake or disk shape can expand when exposed to moisture such that the towel recovers to substantially the original dimensions and texture.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is directed toward an improved barrel ring and to a method for making the improved barrel ring.
2. Description of the Prior Art
Barrel rings are ring-shaped members used in the rolling closure art. Previously, rolling closures were rolled or wound up on a large diameter drum or barrel. The drum however was very heavy and thus difficult to rotate. Barrel rings were developed to replace the drum. The barrel rings are mounted at longitudinally spaced-apart locations on a small diameter support or axle. The outer surfaces of the rings provide the surface on which a closure can be wound. The rings and axle construction is much lighter than the drum construction previously used and thus less effort is needed to wind up the closure. However the barrel rings were one-piece cast members which made them quite expensive.
SUMMARY OF THE INVENTION
It is the purpose of the present invention to provide improved barrel rings which are much less expensive than known barrel rings. It is another purpose of the present invention to provide a method for manufacturing inexpensive, improved, barrel rings. In accordance with the present invention the improved barrel rings are composed of ring sections, the required number of which are joined together end-to-end to form a complete barrel ring. The sections are formed from one or more extruded members, each having a profile of the desired ring section. The extruded members are transversely cut into thin pieces which form the ring sections. Forming the ring sections from an extruded member results in the manufacture of a much cheaper barrel ring than if the ring were cast in one piece. Using extruded ring sections to form a complete barrel ring, instead of using an extruded ring further reduces the cost since an arc profile is cheaper to extrude than a tubular profile. The barrel rings formed from the sections of the extruded member are also lighter than the cast barrel rings, making the closure still easier to operate.
Preferably, each barrel ring is made from two ring sections. One of the ring sections has a part-circular outer surface on which the closure is mounted, and the other ring section has a part-spiral outer surface on which the closure is mounted. The two sections are joined end-to-end to form a barrel ring with the spiral surface, at one end, smoothly merging into the circular surface. The ring sections are assembled into barrel rings on the support or axle at longitudinally spaced-apart locations.
The invention is particularly directed toward a barrel ring for use in rolling closures comprising at least two ring sections. Each ring section has first outer means for use in receiving a closure thereon, second inner means for use in mounting the section on a support, and connecting means at each end of the section. Means are provided for fastening the sections together end-to-end to form the ring.
Preferably, the outer means of the ring sections includes a part-cylindrical, receiving surface and the inner means includes a part-cylindrical mounting surface. In at least one of the sections, the receiving and mounting surfaces are concentric. In at least one of the other sections, the receiving and mounting surfaces are nonconcentric.
In another embodiment of the invention, a barrel ring is provided for use in rolling closures which ring comprises at least two ring sections with one ring section having an outer, closure-receiving, spiral surface and the other ring section having an outer closure-receiving, cylindrical surface. Means are provided for joining the ring sections together end-to-end to form the ring with the spirl surface, at one end, merging with the cylindrical surface.
The invention is further directed toward a closure mounting comprising an elongated support and at least two ring sections mounted on the support, transverse to the longitudinal axis of the support, at each of a plurality of longitudinally spaced-apart locations on the support.
The invention is also particularly directed toward a method for use in manufacturing a barrel ring consisting of two or more ring sections comprising extruding a rigid member having a profile of the desired ring section, and cutting the rigid member transversely into pieces forming the ring sections.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in detail having reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a rolling closure, wind-up mounting employing the barrel rings of the present invention;
FIG. 2 is an end view of the mounting shown in FIG. 1 showing a closure mounted thereon;
FIG. 3 is an end view of one barrel ring section;
FIG. 4 is an end view of another barrel ring section; and
FIG. 5 is a cross-section view of a barrel ring mounted on the axle.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The closure mounting 1 for a rolling closure, in accordance with the present invention, comprises barrel rings 3 mounted on a small diameter axle or support 5 as shown in FIG. 1. The support 5 in turn is rotatably mounted at its ends to fixed supports (not shown). The support 5 comprises a cylindrical tube 7 having a cylindrical outer surface 9. The barrel rings 3 are mounted on the outer surface 9 of the tube 7 at longitudinally spaced-apart locations, each ring 3 extending perpendicular to the longitudinal axis 11 of the tube 7.
The outer surfaces 13 of the barrel rings 3 generally define an imaginary tubular surface 15 on which a rolling closure 17 may be wound as shown in FIG. 2. The imaginary surface 15 has a step 19 extending parallel to the tube axis 11. A part-spiral imaginary surface 21 starts from the bottom of step 19 and forms about half the tubular surface 15. The spiral surface 21 merges into a part-cylindrical surface 23 which forms the other half of the tubular surface 15. The part-cylindrical surface 23 ends at the top of step 19.
The rolling closure 17 comprises a plurality of sections or slats 25 which are hingedly joined to each other along their adjacent long edges, one after the other. The first slat 25a of the closer 17 extends across the rings 3, parallel to the axis 11 of the support tube 7. This first slat 25a rests on the surfaces of the rings 3 defining the part-spiral surface 21 and adjacent the step 19. The slat 25a is connected to the rings 3, and the remainder of the closure 17 is wound onto the rings 3 when the support tube 7 is rotated. The step 19 allows the closure 17, when being wound, to pass smoothly off the part-cylindrical surface 23 onto the first slat 25a.
Each barrel ring 3 preferably comprises two ring sections 31, 33, each ring section 31, 33 forming about one half the ring 3. One of the ring sections 31, as shown in FIG. 3, has first outer means 35 defining an outer, part-circular closure receiving surface 37, and second inner means 39 for use in mounting the ring section 31 on the support tube 7 with surface 37 concentric with the outer surface 9 of the support tube 7. The first means 35 comprises a strip 41 of rigid material curved to have its outer surface form the part-circular, closure receiving surface 37. The second inner means comprises a plurality of mounting pads 43 radially spaced-apart along a part-circular arc 45 within and concentric to outer, part-circular surface 37. Arc 45 has substantially the same radius as the radius of the cylindrical surface 9 of the support tube 7. Each pad 43 is connected to strip 41 by a radial arm 47.
The other ring section 33, as shown in FIG, 4, has first outer means 49 defining an outer, part-circular closure receiving surface 51, and second inner means 53 for use in mounting the ring section 33 on the support tube 7 with surface 51 non-concentric with the outer surface 9 of the support tube 7. The first means 49 comprises a strip 54 of rigid material curved to have its outer surface form the part-circular, closure receiving surface 51. The second inner means 53 comprises a plurality of mounting pads 55 radially spaced-apart along a part-circular are 57 within surface 51. The arc 57 is not however concentric to surface 51. Instead, arc 57 is shifted relative to surface 51 so that one end 59 of strip 55 is much farther away from arc 57 than the opposite end 61 of strip 54 is from arc 57. The distance "D" from the center 63 of arc 57 to the outer surface 51 at the one end 59 of strip 55 is equal to the radius "R" of the surface 37 on the first ring section. A radial arm 65 connects each pad 55 to strip 54, the arms 65 radial to the center 63 of arc 57.
Means are provided on each end of the ring sections 31, 33 for connecting them together to form a barrel ring 3. In more detail, the one ring section 31, as shown in FIG. 3 has a first connecting wall 71 at one end 73 of strip 41. The wall 71 extends inwardly and away from the nearest radial arm 47. An elongated mounting pad 75 is provided at the end of wall 71 on arc 45. A second connecting wall 77 is provided at the other end 79 of strip 41. The second wall 77 is connected at its inner end to a support wall 81 which in turn connects to the end 79 of strip 41. The second wall 77 extends inwardly at an angle "θ", to a radil line 3 from the center of curvature 85 of strip 41, toward the nearest radial arm 47. The angle "θ" is equal to the angle "α" at which the first wall 71 extends to an extension 87 of radial line 83. The support wall 81 preferably extends transversely from the second wall 77 to the end 79 of strip 41 and, together with the second wall 75, defines an outwardly opening notch 89.
The other ring section 33, as shown in FIG. 4, has a first connecting wall 91 at the one end 59 of strip 54 which wall 91 extends inwardly and away from the nearest radial arm 65. An elongated mounting pad 93 is provided at the inner end of all 91 on arc 57. A second connecting wall 95 is provided at the other end 61 of strip 54 which wall 95 extends upwardly and away from the nearest pad 55. The second connecting wall 95 extends at an angle "α" to a radial line 97 extending from the center of curvature 63 of the arc 57. The first connecting wall 91 extends at an angle "θ" to an extension 101 of radial line 97, the angle "θ" preferably being equal to the angle "α".
The ring 3 is assembled by joining the ring sections 31, 33 together end-to-end. The ring 3 is preferably assembled on support tube 7 as shown in FIG. 5. Means are provided to locate and retain each ring section 31, 33 on support tube 7. The locating and retaining means can comprise a pin 103 extending radially inwardly from the center of mounting pad 75 on ring section 31, and a pin 105 extending radially inwardly from the center of mounting pad 93 on ring section 33. A pair of substantially diametrically opposed holes 107, 109 in the wall 111 of support tube 7 receive the pins 103, 105 respectively when the ring sections 31, 33 are mounted end-to-end about support tube 7. When mounted on the support tube 7, the first connecting wall 71 on section 31 receives the second connecting wall 95 on section 33. The two walls 71, 95 are positioned side-by-side and a bolt 113 passes through aligned holes 115, 117 in the walls 71, 95 respectively to joing the walls 71, 95, and thus adjacent ends of the ring sections 31, 33, together. Similarly, second wall 77 on section 31 receives the first connecting wall 91 on section 33. The two walls 77, 91 are positioned side-by-side and a bolt 119, passing through aligned holes 121, 123 in the walls 77, 91, joins them together. Thus, the ring sections 31, 33 are assembled into a rigid ring 3 securely mounted on support tube 7 via locating pins 103, 105 and bolts 113, 119.
When assembled on support tube 7, each ring 3 has a shoulder or step 125 defined by outwardly extending connecting wall 95 on ring section 33. The steps 125 of all the rings 3 on the support tube 7 are aligned. The height of each step 125 is generally equal to the thickness of the slats 25 of the closure 17. The first slat 25a of the closure 17 is positioned across the rings 3 on the support tube 7 on the part-spiral surface 51 of the ring sections 33 and adjacent the steps 125 formed by the second connecting walls 95 on these sections 33. The first slat 25a is fastened to the rings 3 in this position by any suitable fastening means (not shown). The support tube 7 can then be rotated to wind the closure 17 on it with the slats 25 covering the rest of the part-spiral surfaces 51 on the ring sections 33 first, and then smoothly moving to cover the part-circular surfaces 37 of the other ring sections 31. As the closure passes steps 125 it begins to wind smoothly on the first circle of slats now on the rings 3.
In accordance with the present invention, each ring section 31, 33 is formed by first extruding a long, rigid member having the profile of the desired ring section 31, 33. Each member is then cut transversely into slices, each slice forming a complete ring section 31 or 33 except for the connecting holes 115, 117, 121, 123 and the locating pins 103, 105. Each ring section 31, 33 is made wide enough so that it sits on its pads in stable fashion on the outer surface of the support 5. Each section is completed by drilling holes 115, 121 in section 31 and fixing pin 103 to pad 75, and by drilling holes 117, 123 in section 33 and fixing pin 105 to pad 93. The ring sections 31, 33 are then joined end-to-end on support tube 7 to form the barrel rings 3 of the present invention.
While each barrel ring 3 has been described as being made from two ring sections, three or more sections could be employed in each ring. For example a ring could be made from three ring sections, each section providing about one-third the circumference of the ring. Two of the sections could be identical, providing part-circular mounting surfaces, and the other section could provide a part-spiral mounting surface. The ring sections could also be made in different sizes providing barrel rings of varying diameter.
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A barrel ring for use in rolling closures comprising at least two ring sections. One of the ring sections defines a part-circular outer surface. Another of the ring sections defines a part-spiral outer surface. The ring sections are joined together end-to-end to form a barrel ring with the part-spiral surface, at one end, merging smoothly into the part-circular surface.
A method for producing the barrel ring is also disclosed.
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BACKGROUND OF THE DISCLOSURE
[0001] 1. Field of the Disclosure
[0002] This invention relates to a cartridge case processing device for producing, preparing or refurbishing empty cartridge cases.
[0003] 2. Description of the Related Art
[0004] High levels of dimensional accuracy are demanded when preparing cartridge cases, in particular for precision ammunition. Firing a cartridge case leads to an increase in its diameter along its entire length as well as to a linear expansion of the cartridge case. A cartridge case deformed by firing the cartridge must be refurbished to a suitable shape to be reused.
[0005] In view of the aforementioned prior art, it is the object of the present disclosure to provide a cartridge case processing device for producing, preparing and/or refurbishing empty cartridge cases that allows simple tool-free handling, while simultaneously facilitating precise tooling of the cartridge case.
SUMMARY OF THE PRESENT DISCLOSURE
[0006] According to the present disclosure, a trimming and sizing device to produce and prepare empty cartridge cases comprising a trimmer holder in which a die body is received in the lower section and in an upper section a bushing guided shaft is received on which a cutter, an expander die and a decapping pin are coaxially arranged is characterized by the integration of an adjusting nut coaxial with the shaft in an opening in the upper section of the trimmer holder, which when turned relative to the shaft leads to a relative movement of bushing relative to the upper section. The adjusting nut is accessible from the outside of the upper section. When the adjusting nut is turned relative to the shaft it leads to the position of the cutter being adjusted in an axial direction.
[0007] The trimmer holder accommodates all of the components required to trim and calibrate a cartridge case. By turning the adjusting nut integrated in the trimmer holder in a clockwise or counterclockwise direction it is possible to finely adjust the position of the cutter without the need for any tools. The arrangement of the adjusting nut projecting partially above the trimmer holder in a radial direction allows easy access for its operation. Turning the adjusting nut results in a relative movement of the bushing relative to the trimmer holder so that the position of the shaft together with the cutter mounted on the shaft is altered in an axial direction to facilitate carrying out the trimming process with the greatest possible precision. In this manner it is possible to adjust the final position of the cutter simply, conveniently and at the same time with extreme precision.
[0008] This design embodiment sees the adjusting nut joined to the bushing by means of the external thread of the bushing. The adjustment distance traveled by the bushing as a result of turning the adjusting nut is directly proportional to the lead of the external thread of the bushing or rather the corresponding internal thread of the adjusting nut. The axial position of the bushing relative to the upper section of the trimmer holder, which serves as an end stop for the axial movement of the cutter when trimming, is altered relative to the shaft. Consequently, it is easily possible to determine precisely the final position the cutter reaches when trimming the neck section of the cartridge case.
[0009] The trimmer holder is connected to a loading press by means of the die body received in the lower section. The die body is partially screwed into the lower section of the trimmer holder. The die body is partially screwed into the loading press. It is in this manner that the loading press and the trimmer holder are joined together.
[0010] A favorable aspect of the design embodiment is that it is possible for the adjusting nut to partially protrude out of the upper section of the trimmer holder in a radial direction. This makes it possible to manually operate the adjusting nut easily and surely.
[0011] A further embodiment lies in the possibility of adjusting the adjusting nut step-by-step or infinitely variably. Adjusting the axial position of the cutter for fine adjustment purposes instead of infinitely variable adjustment simplifies the trimming process with reproducible settings, and prevents unintentional maladjustment of the position of the cutter that does not correspond to the length the cartridge case is to be shortened in accordance with the caliber. However, infinitely variable adjustability means it is possible to set the position of the cutter to any setting.
[0012] In particular, a locking element is arranged in the upper section of the trimmer holder that can be form-lock engaged with the adjusting nut. The adjusting nut is held in the respective position by means of the locking element so that operating the trimming and sizing device does not alter the undertaken fine adjustment of the cutter when performing the trimming operation. This has the added advantage that the operating person is able to sense that a further step has been undertaken to finely adjust the cutter based on the form-locked engagement.
[0013] In doing so, the locking element is applied with pressure induced by means of a spring element against a radially outward extending surface of the adjusting nut provided with recesses. As a consequence, when setting the cutter by turning the adjusting nut it is necessary to overcome a mechanical resistance. That prevents unintentional maladjustment on the one hand and better retains the individually undertaken steps to make settings on the other.
[0014] Ideally, the recesses are interposed by intermediate, plane surfaces. Thus, when the adjusting nut is turned the locking element slides over the plane surface when moving from one recess to the next, which means an individual step can be heard and felt when the locking element again reaches a corresponding recess.
[0015] The locking element is preferably provided with an at least partially curved surface with which the locking element can engage in one of the recesses.
[0016] The locking element is preferably designed in the form of a ball. To press the ball against the underside of the adjusting nut with constant pressure, a dedicated spring element designed in the form of a coiled spring is assigned to the ball to apply a pressure force to the ball. For this purpose a blind hole has been sunk in the upper section of the trimmer holder parallel to the axis of the shaft, which serves to accommodate the spring element designed in the form of a coiled spring as well as the locking element designed in the form of a ball.
[0017] In the following the invention is explained in more detail with reference to the accompanying drawings. The depicted examples of embodiment do not represent any limitation to the depicted versions, but serve solely to explain a principle of the invention. The same or similar components are indicated with the same reference numbers. In order to be able to illustrate the mode of operation according to the invention highly simplified schematic representations only are depicted in the figures, while no components are depicted that are of no essential significance to the invention. Nevertheless, that does not mean that such components are not present in a solution according to the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 A sectional view of a trimming and sizing device
[0019] FIG. 2 A detailed view II of an upper section of a trimmer holder of the trimming and sizing device as per FIG. 1
[0020] FIG. 3 Enlarged view of detailed view II as per FIG. 2
[0021] FIG. 4 A detailed view IV of an upper section of a trimmer holder of a second design embodiment of the trimming and sizing device as per FIG. 1
[0022] FIG. 5 A view from below of an adjusting nut of the trimming and sizing device
[0023] FIG. 6 A partially sectional side view of the adjusting nut with locking element as per FIG. 5 .
DETAILED DESCRIPTION
[0024] A sectional view of a trimming and sizing device is depicted in FIG. 1 . A loading press, of which just a holder arm section is partially visible, is denoted by the reference numeral 4 . The loading press 4 serves to receive the trimming and sizing device, which includes a die body 14 and other components. The die body 14 has a hollow interior into which a cartridge case 2 can be inserted. The die body 14 is provided with an external thread with which it is possible to screw the die body 14 into a corresponding threaded section of the holder arm section of the loading press 4 . The base 16 of the cartridge case 2 is fixed in position by a case holder 1 into which it is possible to temporarily secure the cartridge case 2 . As indicated by the arrow P the case holder 1 can be moved in a vertical direction by means of a pressing ram 4 . 1 , which is part of the loading press 4 .
[0025] The die body 14 is partially screwed into a lower, horizontally extending section 6 . 1 of an essentially C-shaped trimmer holder 6 . For this purpose the lower section 6 . 1 of the trimmer holder 6 has a through hole with an internal threaded section. A clamping screw 13 serves to squeeze together or loosen the slotted section 6 . 1 of the trimmer holder 6 so that the position of the die body 14 can be adjusted in the trim holder 6 by means of the external thread. The die body 14 joins the trimmer holder 6 to the loading press 4 . An upper section 6 . 2 , which is provided with a through hole, of the trimmer holder 6 extends parallel to the lower section 6 . 1 . The upper section 6 . 2 of the trimmer holder 6 serves to receive a threaded rod 5 that is at least in part provided with a thread, which in turn can be rotated by means of a crank handle 8 arranged on one end of the threaded rod 5 . The crank handle 8 is secured on the threaded rod 5 by means of lock nut 23 . Viewed in the direction of the die body 14 a cutter 12 is arranged coaxially with the threaded rod 5 and secured with a lock nut 7 . The cutter 12 is screwed onto the threaded rod 5 . Below the cutter 12 there is an expander die 3 to which a decapping pin 15 is attached. The expander die 3 and the decapping pin 15 can be designed as a single component. However, it is advantageous when the expander die 3 and the decapping pin 15 are implemented as separate components, so that it is easily possible to replace the decapping pin 15 when necessary. To achieve a coaxial arrangement on the threaded rod 5 the cutter 12 , the expander die 3 as well as the decapping pin 15 are screwed separately from one another onto a threaded section, not shown, of the threaded rod 5 . This arrangement results in the essential advantage that the individual production-related tolerances of the cutter 12 , expander die 3 as well as the decapping pin 15 do not stack up as is the case with elements screwed into one another.
[0026] The crank handle 8 is arranged on the threaded rod 5 above the upper section 6 . 2 of the trimmer holder 6 . To provide rotatable support of the threaded rod 5 this is partially enclosed by a plain bush 10 . A lower part of the plain bush 10 that faces away from the crank handle 8 is received in a stop bushing 9 with a flange-shaped edge. The flange-shaped edge of the stop bushing 9 is supported on its underside of the upper section 6 . 2 of the trimmer holder 6 . An upper part of the plain bush 10 that faces towards the crank handle 8 is received in a bushing 25 provided with an external threaded section 31 . There is a lock nut, 11 and 24 , located at both respective ends of the plain bush 10 .
[0027] In FIG. 2 there is a detailed view II depicting an upper section 6 . 2 of a trimmer holder 6 of the trimming and sizing device as per FIG. 1 . The drawing in FIG. 3 shows an enlarged view of the detailed view II as per FIG. 2 ; however, to achieve a better representation FIG. 3 dispenses with an illustration of the upper section 6 . 2 of the trimmer holder 6 .
[0028] As can be seen in FIG. 2 and FIG. 3 , the upper bushing 25 is provided with an external threaded section 31 preferably designed as a fine thread. The bushing 25 provided with an external threaded section 31 is received by means of a corresponding internal thread 30 of an adjusting nut 26 that is coaxially arranged with the threaded rod 5 , as depicted in FIG. 6 , which is integrated in the upper section 6 . 2 of the trimmer holder 6 of the trimming and sizing device. In order to integrate the ring-shaped adjusting nut 26 in the trimmer holder 6 depicted in the embodiment, the upper section 6 . 2 is provided with a corresponding opening, in particular slot-shaped opening. The adjusting nut 26 protrudes partially above the upper section 6 . 2 of the trimmer holder 6 in a radial direction so that it is possible to access and turn the adjusting nut 26 from outside of the device.
[0029] Alternatively, the adjusting nut 26 can for example be provided with a polyhedral external contour, preferably a hexagonal external contour, so that it can, for example, be operated using an open-ended wrench. At the same time, it is possible to design the dimensions of the adjusting nut 26 in such a manner that it does not protrude outside of the upper section 6 . 2 of the trimmer holder 6 .
[0030] According to a further embodiment of the adjusting nut 26 , it is possible to provide this with drilled blind holes distributed evenly around its external circumference into which it is possible to insert a pin with which to turn the adjusting nut 26 . The bushing 25 is fixed in position in the upper section 6 . 2 of the trimmer 6 holder by means of a threaded pin 20 that extends vertically to the longitudinal axis of the threaded rod 5 , to prevent any rotational movement of the bushing 25 relative to the threaded rod 5 . For this purpose, the bushing 25 is provided with a groove 22 that extends parallel to the axis of the threaded rod 5 . The threaded pin 20 engages in this groove 22 . The freedom of the bushing 25 to move in a longitudinal direction along the threaded rod 5 is equally restricted by the threaded pin 20 .
[0031] A tapped hole designed to receive the threaded pin 20 is preferably located on the side of the trimmer holder 6 facing that section of the adjusting nut 26 that protrudes above the upper section 6 . 2 of the trimmer holder 6 . Furthermore, a drilled blind hole 21 is provided in the upper section 6 . 2 of the trimmer holder 6 that is arranged parallel to the axis of the threaded rod 5 . Inside the drilled blind hole 21 there is a spring element 18 , for example a coiled spring, designed as a compression spring as well as a locking element designed in the form of a ball 19 . Instead of a ball, it is also possible to use a cylindrically shaped element with a curved end face as a locking element. For instance, it is also conceivable to use an essentially mushroom shaped locking element without impairing the function. Designed as a coiled spring the spring element 18 is supported at one end by the floor of the drilled blind hole 21 and presses the locking element designed as a ball 19 against the underside of the adjusting nut 26 with its other end. When ejecting a primer out of the base 16 of the cartridge case 2 , which leaves an opening 17 in the base 16 of the cartridge case 2 , the act of ejecting the primer by means of the decapping pin 15 briefly generates a pressure force. The cartridge case 2 is pressed into the die body 14 to size the cartridge case 2 . The pressure force generated when ejecting the primer is absorbed by the threaded rod 5 and the lock nut 11 , and transmitted to the flange-shaped edge of the stop bushing 9 . The stop bushing 9 is in turn supported via its flange-shaped edge by the upper section 6 . 2 of the trimmer holder 6 . This design embodiment prevents the forces being transmitted to the external threaded section 31 of the bushing 25 or rather the internal thread 30 of the adjusting nut 26 .
[0032] The drawing in FIG. 4 shows a detailed view IV depicting an upper section 6 . 2 of the trimmer holder 6 of a second embodiment of the trimming and sizing device as per FIG. 1 . This embodiment differs from the first described embodiment as per FIG. 2 and FIG. 3 in as much that it does not require the stop bushing 9 with a flange-shaped edge. Instead, a bushing 25 . 1 coaxially arranged with the threaded rod 5 extends in an axial direction of the drilled blind hole at least as far as the total axial extension of the upper section 6 . 2 of the trimmer holder 6 . This bushing 25 . 1 receives the plain bush 10 , which encloses the threaded rod 5 . In the same manner as the bushing 25 described in the first embodiment example, the bushing 25 . 1 is also provided with groove 22 that extends parallel to the axis of the threaded rod 5 . The threaded pin 20 engages in this groove 22 so that the bushing 25 . 1 is secured to prevent it twisting. The freedom of the bushing 25 . 1 to move in a longitudinal direction along the threaded rod 5 is equally restricted by the threaded pin 20 .
[0033] As described above, the bushing 25 . 1 is provided with an external thread 31 , which is engaged with the internal thread 30 of the adjusting nut 26 so as to facilitate achieving a fine adjustment of the axial position of the cutter 12 by turning the adjusting nut 26 . Turning the adjusting nut 26 effects a relative movement of the bushing 25 . 1 in relation to the upper section 6 . 2 of the trimmer holder 6 . Together with the bushing 25 . 1 the position of the plain bush 10 received in the bushing 25 . 1 as well as that of the threaded rod 5 also changes. When ejecting the primer out of the cartridge case 2 , the act of ejecting the primer by means of the decapping pin 15 briefly generates a pressure force. When ejecting the primer this pressure force is transmitted by the threaded rod 5 and the lock nut 11 to the bushing 25 . 1 or rather to its external thread 31 and the internal thread 30 of the adjusting nut 26 , which are in turn supported at the upper section 6 . 2 of the trimmer holder 6 .
[0034] The drawings in FIG. 5 and FIG. 6 show the adjusting nut 26 when viewed from below as well as in a partially sectional view. As can be seen in the drawing in FIG. 5 the adjusting nut 26 is provided with recesses 27 arranged and distributed evenly on its underside in a circumferential direction that extend in a radial direction across the entire width of the underside. The adjacent recesses 27 are separated from one another by plane surfaces 28 on the underside of the adjusting nut 26 . The drawing in FIG. 6 shows how the coiled spring 18 presses the ball 19 into one of the recesses 27 by means of spring force to secure the adjusting nut 26 in position. Knurling 29 is provided on the outside circumference of the adjusting nut 26 to provide additional grip when operating the adjusting nut 26 .
[0035] The fundamental mode of operation of sizing and trimming of this trimming and sizing device is known from the DE 10 2010 048 117 A1 or rather the corresponding Patent U.S. Pat. No. 8,408,112 B2, which are hereby incorporated by reference. However, the described trimming and sizing device according to the present disclosure differs from the device described in the DE 10 2010 048 117 A1 by the embodiment of a means to simplify the setting of the vertical position of the cutter 12 in combination at the same time with the highest accuracy when setting the required length to which the cartridge case 2 is to be shortened at the bullet end.
[0036] Turning the adjusting nut 26 integrated in the trimming and sizing device in its circumferential direction to the left or right results in transposing the ball 19 from one recess 27 to an adjacent recess, into which it clearly perceptibly and audibly engages. This ensures the user is made aware of the individual steps when making settings, which in conjunction with the pitch of the internal thread of the adjusting nut 26 or rather of the external threaded section 31 of the bushing 25 or the bushing 25 . 1 , make it possible to precisely set the axial position of the cutter 12 . This embodiment makes it possible to make settings in steps within a range of hundredths of a millimeter (in a range of thousandths of an inch steps). The size of the setting step depends on the thread lead on the bushing 25 or rather 25 . 1 as well as the adjusting nut 26 . In addition, the size of the setting step is also influenced by the number of recesses 27 as well as the number of plane surfaces 28 between the recesses 27 , as shown in FIG. 5 .
[0037] When performing the trimming operation by turning and simultaneously pressing down on the crank handle 8 the cartridge case 2 is shortened by the cutter 12 to the length appropriate to the corresponding caliber. The maximum depth the cutter 12 can achieve is restricted by the bushing 25 or rather the bushing 25 . 1 , which serves as an end stop for the crank handle 8 . In using the adjusting nut 26 it is possible to set the end position of the cutter 12 in relation to the base 16 of the cartridge case 2 that the cutter 12 reaches at the end of the trimming procedure; in other words, with the adjusting nut 26 it is possible to set the minutest of axial distances that the cutter 12 can travel in relation to the base 16 of the cartridge case 2 when trimming. According to the present disclosure, this embodiment guarantees precision, reproducible shortening of the cartridge case 2 .
LIST OF REFERENCE SIGNS
[0000]
1 Case holder
2 Cartridge case
3 Expander die
4 Loading press
4 . 1 Pressing ram
5 threaded rod
6 Trimmer holder
6 . 1 Lower section of the trimmer holder 6
6 . 2 Upper section of the trimmer holder 6
7 Lock nut of cutter 12
8 Crank handle
9 Stop bushing
10 Plain bush
11 Lock nut of plain bush 10
12 Cutter
13 Clamping screw
14 Die body
15 Decapping pin
16 Base of cartridge case 2
17 Opening in base 16
18 Coiled spring
19 Ball
20 Threaded pin
21 Drilled blind hole
22 Groove
23 Lock nut of crank handle 8
24 Lock nut of plain bush 10
25 Bushing
25 . 1 Bushing
26 Adjusting nut
27 Recess
28 Surface on underside of adjusting nut 26
29 Knurling
30 Internal thread of adjusting nut 26
31 External threaded section
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The present disclosure relates to a cartridge case processing device to produce and prepare empty cartridge cases ( 2 ) comprising a trimmer holder ( 6 ) in which a die body ( 14 ) is received in the lower section ( 6.1 ) and in an upper section ( 6.2 ) a bushing ( 25, 25.1 ) guided shaft ( 5 ) is received on which a cutter ( 12 ), an expander die ( 3 ) and a decapping pin ( 15 ) are coaxially arranged characterized by the integration of an adjusting nut ( 26 ) coaxial with the shaft ( 5 ) in the upper section ( 6.2 ) of the trimmer holder ( 6 ), which when turned relative to the shaft ( 5 ) leads to the position of the cutter ( 12 ) being adjusted in an axial direction.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a control unit for two variable displacement compressors used for two independent air-conditioning systems.
[0003] 2. Description of the Related Art
[0004] In the prior art, a variable displacement compressor of a regularly operative type for an air-conditioner of a vehicle, which is regularly operative by a power from an engine provided the engine is driven, is known from Japanese Unexamined Patent Publication (Kokai) No. 2000-220577. This compressor is capable of optionally changing the operating displacement in a range of approximately 0% to 100% by electric signals from an electronic control unit (ECU) in accordance with various operating conditions. When the air conditioning in a passenger compartment is necessary, the compressor is switched to an ON mode in which a coolant is compressed by the compressor based on the signal from ECU and discharged to an air-conditioning cycle. If the air conditioning in the passenger compartment is unnecessary, the compressor is switched to an OFF mode, which is a minimum displacement operation, and no coolant is discharged to the air conditioning cycle.
[0005] While sliding portions in the interior of the compressor usually become hot due to self-heating during the operation, in the case of the ON mode, the sliding portions are cooled because coolant at a low temperature is sucked from the air conditioning cycle into the compressor. On the other hand, in the case of the OFF mode, in which no air conditioning is carried out, as no coolant is sucked from the air conditioning cycle into the compressor, the interior sliding portions of the compressor are not cooled by the coolant. When the air is at a relatively low temperature, the compressor is usually driven in the OFF mode as the passenger requires no air conditioning. However, the interior temperature of the compressor does not rise to a dangerous value because the outer air temperature is low. Conversely, in an environment with a high air temperature, the compressor is driven in the ON mode because the air conditioning is usually necessary, and the compressor temperature does not rise to an extraordinary high value.
[0006] However, in a case of a large-sized vehicle such as a limousine having two air conditioning systems using two compressors, completely independent from each other, in which one compressor is used for the front seats and another compressor is used for the rear seats, the compressor for the rear seats may be operated in the OFF mode when the air temperature is high but there are no passengers in the rear seats. When the compressor is driven in the OFF mode at such a high air temperature, no cooling effect is obtainable from a returning coolant from the air conditioning cycle. Thus, the temperature of the compressor reaches a dangerous temperature due to self-heating to result in the seizing of the compressor in the worst case.
SUMMARY OF THE INVENTION
[0007] The present invention has been made to solve the above-mentioned problems in the prior art, and an object thereof is to provide a control unit for two variable displacement compressors directly coupled to a common external drive source and used for two completely independent air conditioning systems, which control unit is capable of preventing the compressor temperature from rising to a dangerous value by the self-heating due to the OFF mode operation of the compressor and from a resulting seizing of the compressor when the air temperature is at a predetermined value or higher.
[0008] According to the present invention, in an air-conditioner having at least two variable displacement compressors directly coupled to a common external drive source and used for at least two independent air conditioning cycles, provision is mode of a control unit for the variable displacement compressors which comprises detection means for detecting the air conditioning state of one of the two variable displacement compressors wherein, when the detection means detects a predetermined condition, both of the compressors are subjected to the variable displacement operation even though the only air conditioning operation of the other variable displacement compressor is necessary.
[0009] Thereby, irrespective of whether or not the air conditioning operation is necessary, when one of the air conditioning systems is operated, the other system is also operated so that seizing of the compressor due to self-heating of the compressor is avoided due to the cooling effect of the returning coolant.
[0010] In the present invention, the detection means is preferably means for detecting the air temperature, and the predetermined condition is that the air temperature is higher than a predetermined value.
[0011] The present invention may be more fully understood from the description of the preferred embodiments of the invention, as set forth below, together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] In the drawings:
[0013] [0013]FIG. 1 is a sectional view of a swash plate type variable displacement compressor;
[0014] [0014]FIG. 2 illustrates an entire structure of an air conditioning system having two independent air conditioning cycles using two variable displacement compressors; and
[0015] [0015]FIG. 3 is a flow chart for controlling the control unit for the variable displacement compressor according to one embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] The control unit for the variable displacement compressor according to the embodiment of the present invention will be described below with reference to the attached drawings. FIG. 1 is a sectional view of a variable displacement compressor of a regularly operative type. The variable displacement compressor 100 of this type is adapted to be regularly operative by a power from an external drive source 8 provided the external drive source 8 such as an engine is in an ON mode.
[0017] As shown in FIG. 1, a front housing 110 is coupled to a front end of a cylinder block 111 , and a rear housing 113 is fixedly coupled to a rear end of the cylinder block 111 via a plate member 115 such as a valve plate or a valve-forming plate. A rotary shaft 104 is supported for rotation by the front housing 110 and the cylinder block 111 defining a crank chamber 107 . A shock absorber 102 having a pulley 101 and a hub 103 is fastened by bolts or the like to the rotary shaft 104 projected outward from the crank chamber 107 through the shock absorber 102 . Power is transmitted from the external drive source such as a vehicle engine to the pulley 101 via a belt (not shown) or the like and further to the rotary shaft 104 .
[0018] A lug plate 105 is made integral with the rotary shaft 104 by, for example, press-fitting or others, and a swash plate 108 is supported by the rotary shaft 104 to be slidable in the axial direction thereof and tiltable thereto. A connecting piece 108 a is fixed to the swash plate 108 and a guide pin 106 is integral with the connecting piece 108 a by a press-fit or others. A guide hole 105 a is formed in the lug plate 105 , and a head of the guide pin 106 is inserted into the guide hole 105 a in a slidable manner. The swash plate 108 is tiltable in the axial direction of the rotary shaft 104 in association with the guide hole 105 a and the guide pin 106 and is rotatable together with the rotary shaft 104 .
[0019] When a center portion of the swash plate 108 moves toward the cylinder block 111 , the inclination angle of the swash plate 108 increases. The maximum inclination angle of the swash plate 108 is limited by the contact of the lug plate 105 with the swash plate 108 . The minimum inclination angle of the swash plate 108 is limited by the contact of the swash plate 108 with a circlip 116 provided on the rotary shaft 104 .
[0020] In a plurality of cylinder bores 111 a formed in the cylinder block 111 , pistons 112 are accommodated. The rotary motion of the swash plate 108 is converted to the forward and rearward reciprocation of the pistons 112 , whereby the respective piston 112 is slidable along the cylinder bore 111 a forward and rearward. Accordingly, there are main sliding portions of this compressor 100 between the swash plate 108 and the shoe 109 and between the piston 112 and the bore 111 a.
[0021] In the rear housing 113 , a suction chamber 117 and a discharge chamber 118 are defined. In the plate member 115 interposed between the cylinder block 111 and the rear housing 118 , such as a valve sheet or a valve-forming plate, a suction valve and a discharge valve are formed. Accordingly, a gasous coolant in the suction chamber 117 pushes back the suction valve due to the returning motion of the piston 112 and flows into the cylinder bore 111 a . The gasous coolant thus flowing into the cylinder bore 111 a pushes back the discharge valve due to the advancing motion of the piston to be discharged into the discharge chamber 118 .
[0022] In a pressure supplying path connecting the discharge chamber 118 to the crank chamber 107 , an electromagnetic type displacement control valve 114 is provided. This pressure supplying path is a path for supplying a coolant in the discharge chamber 118 which is a discharging pressure area to the crank chamber 107 . On a bellows 114 a within the displacement control valve 114 which is a pressure-sensitive means, the pressure in the suction chamber 117 (a suction pressure) is applied. The suction pressure within the suction chamber 117 is influenced by a heat load. A valve body 114 b is connected to the bellows 114 a and opens or closes a valve hole 114 c . A spring force of a spring in the bellows 114 a acts on the valve body 114 b in a direction to open the valve hole 114 c . An electromagnetic drive force of a solenoid 114 d in the displacement control valve 114 biases the valve body 114 b to close the valve hole 114 c against the spring force. The electric current supplied to the solenoid 114 d is controlled by an electronic control unit (ECU) 7 as shown in FIG. 2.
[0023] ECU 7 supplies the electric current to the solenoid 114 d when a switch for operating an air conditioning system is in an ON state, and stops the electric current when the switch is in an OFF state. An electric signal from ECU 20 , which becomes a control current for the solenoid 114 d , is determined by processing, in the ECU 7 , an air conditioning environment such as a passenger compartment temperature, a solar radiation or an outer air temperature; a condition for operating an air conditioner such as an operating switch, an air conditioner operative mode or a set temperature; and a vehicle environment such as an engine rotational speed, or an opening degree of accelerator. An opening degree of the displacement control valve 114 is determined by a balance between an electromagnetic drive force generated from the solenoid 114 d , a spring force and a bias of the bellows. Accordingly, the displacement control valve 114 carries out the control for generating a suction pressure in correspondence to the current value supplied to the solenoid 114 d.
[0024] As the current value supplied to the solenoid 114 d becomes higher, the opening degree of the displacement control valve 114 becomes smaller to reduce an amount of coolant supplied from the discharge chamber 118 to the crank chamber 107 . As the coolant in the crank chamber 107 flows to the suction chamber 117 via a pressure-release path, the interior pressure in the crank chamber 107 is lowered. Accordingly, an inclination angle of a swash plate 108 becomes larger to increase a discharged amount of the coolant. The increase of the discharging amount results in the lowering of the suction pressure. When the current value supplied to the solenoid 114 d becomes lower, the opening degree of the displacement control valve 114 becomes larger to increase the amount of the coolant supplied from the discharge chamber 118 to the crank chamber 107 . Accordingly, the interior pressure of the crank chamber 107 rises to decrease the inclination angle of the swash plate 108 and reduce the discharge amount of the coolant. The reduction of the discharge amount results in the increase of the suction pressure.
[0025] If the current value supplied to the solenoid 114 d becomes zero, that is, when the compressor 100 is operated in an OFF mode, the opening degree of the displacement control valve 114 is maximum and the inclination angle of the swash plate is minimum. When the inclination angle of the swash plate 108 becomes minimum, the coolant suction path is closed to interrupt the circulation of the coolant through an external coolant circuit, whereby the cooling of the passenger compartment is not carried out. When the current is supplied again to the solenoid 114 d , the opening degree of the valve becomes smaller to lower the pressure in the crank chamber 107 , and the inclination angle of the swash plate 108 increases from the minimum value. As the inclination angle of the swash plate 108 increases from the minimum value, the suction path is opened and the coolant flows from the suction path to the suction chamber 117 , whereby the circulation of the coolant through the external coolant circuit is started again to carry out the cooling of the passenger compartment.
[0026] [0026]FIG. 2 illustrates an entire structure of two completely independent air conditioning systems using two variable displacement compressors. These first and second compressors 1 and 11 are connected via belts or others (not shown) to the external drive source 8 such as an engine from which power is transmitted.
[0027] The first air conditioning system forms an air conditioning cycle for circulating a hot and high pressure gaseous coolant discharged from the first compressor 1 through an external coolant circuit sequentially consisting of a first condenser 2 , a first receiver 3 , a first expansion valve 4 and first evaporator 5 , and returning to the first compressor 1 .
[0028] The second air conditioning system forms an air conditioning cycle for circulating a hot and high pressure gaseous coolant discharged from the second compressor 11 through an external coolant circuit sequentially consisting of a second condenser 12 , a second receiver 13 , a second expansion valve 14 and second evaporator 15 , and returning to the second compressor 11 . As the function of the coolant is well-known in the air conditioning cycle, the explanation thereof will be eliminated.
[0029] The first electromagnetic displacement control valve 6 in the first compressor 1 and the second electromagnetic displacement control valve 16 in the second compressor 11 are respectively controlled by electric signals 9 , 19 from the electronic control unit (ECU) 7 . The air conditioning environment such as the air temperature, the condition for operating (setting) the air conditioner such as an operating switch or a set temperature and the vehicle environment such as an engine rotational speed are input into ECU 7 and processed therein to output electric signals 9 , 19 to the displacement control valves 6 , 16 , respectively.
[0030] When the air conditioning system is operated in the ON mode by using the above-structured variable displacement compressors 1 , 11 and 100 ; that is, when the variable displacement control valves 6 , 16 and 114 are driven by ECU 7 to increase the inclination angle of the swash plate 108 in the respective compressor from the minimum value so that the coolant circulates the external coolant circuit, sliding portions in the compressor, for example, between the swash plate 108 and a shoe 109 or between a piston 112 and a cylinder bore 111 a are heated by the sliding motion. However, this heat generation is cooled by the coolant returning from the air conditioning cycle. On the other hand, in the OFF mode (the minimum displacement operation) of the compressors 1 , 11 and 100 in which no air conditioning operation is necessary, that is, when the displacement control valves 6 , 16 , 114 are not driven and the inclination angle of the swash plate 108 is a minimum to interrupt the circulation of the coolant through the external coolant circuit, the effect for cooling the heated sliding portions is not obtainable by the coolant returning from the air conditioning cycle. However, as the outer air temperature is low in an environment requiring no air conditioning, the compressor does not reach a dangerous zone in which the sliding portions are seized by self-heating.
[0031] However, as shown in FIG. 2, in a case of a large-sized vehicle having two independent air conditioning cycles, a first air conditioning system for the front seats and a second air conditioning system for the rear seats may be mounted to the vehicle. When the air temperature is relatively high and there is no passenger other than a driver in the vehicle, the first air conditioning system must be operated as the driver needs the air conditioning, whereby the first compressor 1 is operated in the ON mode. That is, the electric signal 9 is sent from ECU 7 to the first electromagnetic type displacement control valve 6 and the first compressor 1 carries out the variable displacement operation to circulate the coolant through the external coolant circuit thereof. Therefore, while the sliding portions of the first compressor 1 are cooled by the returning coolant in the first air conditioning system, the second air-conditioning system for the rear seats is not operative as there are no passengers and the second compressor 11 is operated in the OFF mode. That is, no electric signal 19 is sent from ECU 7 to the second electromagnetic type displacement control valve 16 and the second compressor 11 carries out the minimum displacement operation, in which no coolant is supplied to the external coolant circuit thereof. Therefore, even though the air temperature is high, the second compressor 11 is not cooled by the coolant returning from the air conditioning cycle and is forced to be driven at a high temperature due to self-heating, whereby the sliding portions of the second compressor 11 may reach to a high temperature state and may be in an oil-film broken state to result in seizing.
[0032] To solve such a problem, the control unit for the variable displacement compressor according to one embodiment of the present invention controls the operation of the air conditioning system in accordance with a control flow shown in FIG. 3. For example, if a driver is a sole passenger of the vehicle, to operate the first air conditioning system for the front seats, the first electromagnetic type displacement control valve 6 is initially driven by the electric signal 9 from ECU 7 to drive the first compressor 1 in the ON mode at step S 1 . Then, at step S 2 , it is determined by ECU 7 whether or not the air temperature is higher than a predetermined value T o . If the answer is affirmative, the routine proceeds to step S 3 at which the electric signal 19 is sent from ECU 7 to the second electromagnetic displacement control valve 16 which is driven thereby to operate the second compressor 11 in the ON mode, whereby the second air conditioning system for the rear seats is operated. Contrarily, if the answer is negative, the routine proceeds to step S 4 , at which the second air conditioning system for the rear seat is not operated and the second compressor 11 is maintained in the OFF mode.
[0033] In such a manner, according to the present invention, as a control system in which, when the outer air temperature is higher than the predetermined temperature T o and the driver uses the air conditioning system, the second air conditioning system for the rear seats is operated by issuing the electric signal 19 from ECU 7 irrespective of whether or not there are passengers in the rear seats so that the second compressor 11 is operated in the ON mode, is adopted, it is possible to avoid the seizing of the sliding portions of the compressor and maintain the reliability thereof.
[0034] While the present invention has been described by reference to specific embodiments chosen for the purposes of illustration, it should be apparent that numerous modifications could be made thereto by those skilled in the art without departing from the basic concept and scope of the invention.
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A control unit for variable displacement compressors is used for two independent air conditioning cycles, wherein two compressors 1, 11 driven by a common external drive source 8 include electromagnetic displacement control valves 6, 16, respectively. By controlling these control valves by ECU 7, the displacement of the compressor is variable. When the air temperature is higher than a predetermined temperature T o , both of the compressors are subjected to the variable displacement operation even though one of them is unnecessary for the air conditioning operation. On the contrary, if the outer air temperature is lower than the predetermined temperature, only one compressor, needed for the air conditioning operation, is subjected to the variable displacement operation, while the other compressor is subjected to the minimum displacement operation.
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STATEMENT OF GOVERNMENT INTEREST
The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.
BACKGROUND OF THE INVENTION
This invention relates to gallium arsenide semiconductor devices and to a method for their fabrication. More particularly, this invention concerns itself with the fabrication of tellurium implanted submicron N-type layers in gallium arsenide semiconductors and to the use of aluminum nitride as an encapsulating medium during the high temperature annealing step used in the fabrication process.
In recent times, gallium arsenide has become a basic semiconductor material for the production of microwave devices. It exhibits excellent semiconductor properties, particularly at higher temperatures and at both higher and lower frequencies than are usable with germanium or silicon. This is attested to by its increased use in the fabrication of rectifiers, transistors, photoconductors, light sources, light emitters, and maser and laser diodes. The majority of these microwave devices are constructed by epitaxial doping techniques since an N-type diffusion technology in gallium arsenide has not been established. However, even though epitaxial methods are successful, it has been difficult to produce uniform dopant layers less than a few tenths of a micron in thickness.
In an attempt to overcome this problem, it has been found that ion implantation is an effective and efficient process for doping gallium arsenide. It provides accurate control for the doping process and lends itself well to mass production.
In addition to the doping of active regions, ion implantation can be utilized to reduce GaAs contact resistance. For most devices it is essential to have the lowest resistance Ohmic contact possible. The generation of excessive Ohmic heating limits the output power of such devices as laser diodes, impatt diodes and Gunn oscillators.
Some early attempts at the N-type doping of GaAs suggested the use of room temperature implantation and an SiO 2 anneal overcoat. However, room temperature implantation in GaAs was found to lead to lower electrical activity than hot substrate implantation. In addition, gallium readily diffuses through SiO 2 , and in the case of tellurium implantation, this loss of gallium has been found to result in Ga vacancy-Te complexes after anneal.
In considering the ancillary problem posed through the use of a SiO 2 overcoat, it was suggested that Si 3 N 4 be used since it provides an excellent mask against gallium or arsenic diffusion.
Unfortunately, the ion implantation of N-type layers in GaAs has not been a consistently reproducible process. Electrical activities over a wide range have been observed for identical implant conditions and substrates. This has been attributed largely to the often poor adherence of sputtered Si 3 N 4 during the annealing process. This problem of adherence may be related to the facts that it is difficult to sputter oxygen-free Si 3 N 4 and the thermal mismatch between Si 3 N 4 and GaAs is large. Also, the composition and strain characteristics of sputtered Si 3 N 4 may be quite different than Si 3 N 4 deposited by other techniques.
In an effort to obtain more uniform results, considerable research was conducted on the effect of changing the anneal overcoat. The objective was to find a dielectric layer with improved adherence and masking qualities that would result in consistently high electrical activity. Sputtered AlN was found to be the most effective anneal overcoat for this work since it has an expansion coefficient of 6.1×10 -6 /° C which closely matches the GaAs value. In addition, any oxygen incorporated in the AlN film would be in the form of Al 2 O 3 , not SiO 2 as in the case of Si 3 N 4 . The process provides an effective method for producing tellurium implanted N-type layers in gallium arsenide.
SUMMARY OF THE INVENTION
In accordance with the method of this invention, the formation of submicron N-type layers of tellurium in gallium arsenide can be effectively accomplished through the use of an ion implantation technique. The implantation was performed with gallium arsenide substrates held at 350° C. After implantation, a protective overcoat of AlN was sputtered on the samples to prevent the GaAs from disassociating during anneal (900° C). The electrical characteristics of the N-type implants were then measured. Current-voltage and capacitance-voltage characteristics of implanted diodes indicated that the junctions were linearly graded and that there was no intrinsic layer present after anneal. Sheet resistivity and Hall effect measurements were used to determine the surface carrier concentration and effective mobility in the implanted layers. Ionized impurity profiles extending beyond the implanted junction depth were calculated by matching differential Hall effect date with junction capacitance-voltage data. A peak electron concentration of 7 × 10 18 electrons/cm 3 was observed.
Accordingly, the primary object of this invention is to provide a novel technique for the formation of submicron N-type layers in a gallium arsenide substrate.
Another object of this invention is to provide a protective technique for preventing the disassociation of a gallium arsenide substrate during anneal at elevated temperatures.
Still another object of this invention is to provide a technique for the ion implantation of a tellurium dopant into a gallium arsenide substrate.
A further object of this invention is to provide a technique for utilizing aluminium nitride as a protective overcoat during the anneal of a tellurium doped gallium arsenide substrate in order to prevent the diffusion of gallium and arsenic through the protective overcoats previously used in the art.
The above and still further objects and advantages of this invention will be better understood by referring to the following detailed description thereor when taken in conjunction with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 represents a graphical illustration of the energy spectrum of 2 MeV He ions backscattered from an AlN coated GaAs sample.
FIG. 2 represents a graphical illustration showing the capacitance-voltage characteristics of two ion implanted diodes.
FIG. 3 is a graphical illustration showing the electron concentration and mobility profiles for a tellurium implanted sample processed with a Si 3 N 4 coating during anneal.
FIG. 4 is a graphical illustration showing electron concentration and mobility profiles for a tellurium implanted sample processed with an AlN coating during anneal.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the present invention, samples were prepared in a conventional manner from Cd doped P-type GaAs with a measured carrier concentration of 2.3×10 17 holes/cm 3 and a mobility of 196 cm 2 /v-sec. Implantations of 220 keV tellurium were performed at 350° C into the GaAs substrates with the incident beam at least 10° from any low-index axis. Ion doses ranged from 3×10 13 to 3×10 14 Te/cm 2 . For the lower dose samples, an additional implant was made at 60 keV with a dose one-third the 220 keV dose.
After implantation, AlN or Si 3 N 4 was sputtered on the samples, to compare the properties of the two anneal overcoats. The samples were then annealed at 900° C for 10 minutes in flowing hydrogen. Photoresist lifting techniques were employed to make ohmic contacts to the implanted layers. A 400 A layer of Au-Ge), (12 weight percent Ge), followed by a 500A layer of Ni was evaporated on the resist-coated implants. Thin films of Au-Ge were chosen to avoid shorting the implanted junction as Au-Ge is known to penetrate deeply into GaAs during alloying. The contacts were alloyed at 450° C for 2 minutes in a hydrogen atmosphere. Mesa etching was used to define the Hall patterns and various diode structures.
Backscattering measurements on AlN layers were performed using a 3 MV accelerator. The specimens were exposed to 2 MeV He + ions and the energy spectrum of the backscattered ions was recorded. Standard backscattering analysis techniques were applied to the spectra in order to determine the composition of the AlN layers.
To determine the carrier concentration and mobility profiles in the implanted samples, sheet resistivity and Hall effect measurements were performed as a function of layer removal. Thin layers were stripped from the implanted surface by etching the sample in a solution of equal parts H 2 SO 4 and H 2 O 2 to 100 parts H 2 O. During the etch, the contact pads and channels to the Hall pattern were protected by black wax. The thickness of the removed layers was calculated by performing interferometry measurements on the GaAs step after the final strip had been completed.
Capacitance-voltage and current-voltage measurements were made in the dark on small area diodes (1.67×10 -4 cm 2 ). By analyzing the junction C-V data, it was possible to extend the carrier concentration profile to beyond the junction depth. Scanning electron microscopy was used to determine the junction depth.
In the past, there have been problems with gallium or arsenic out-diffusing through the dielectric overcoat during anneal. FIG. 1 compares backscattering spectra taken before and after anneal of an AlN coated GaAs sample. The counts beyond 1.4 MeV indicate there are trace impurities in the AlN film. However, since there is no change in the spectrum after anneal, it can be concluded that there was no pronounced gallium or arsenic out-diffusion during the anneal. If either gallium or arsenic were present in the film, they were in concentrations of less than 2%.
Scanning electron microscopy verified that the AlN adhered to GaAs during anneal. The surface of an AlN overcoated GaAs sample was smooth and featureless after annealing at 850° C for 15 minutes.
The current-voltage characteristics of several implanted diodes were measured in the range of 10 -11 to 10 -2 amps. The forward characteristic of an ideal GaAs diode generally follows the relation 1=1 o exp(qV/nkT) where n=2. Only in one case as shown in Table I, was such an ideal behavior observed. Most of the implanted diodes had a forward characteristic n value equal to 1.15. This low value of n is interpreted to be the result of surface recombination since in all cases the forward current scaled as a function of junction area. The reverse characteristics were of varied quality. Some had better reverse characteristics than previously known diffused structures of similar substrate doping. Others, however, had high leakage currents and low breakdown voltages. Since the leakage was mostly junction area dependent, the deep penetration of the Au-Ge contacts may have been the cause of these poor characteristics.
Examination of the cleaved edge of one of the ion implanted diodes using a scanning electron microscope showed fingers of alloyed Au-Ge penetrating to depths of 1200A ± 200A deep in the GaAs. If the junction region were not heavily doped, a low voltage breakdown would occur as the depletion layer approached the alloyed Au-Ge.
Capacitance-voltage measurements indicated that all the junctions were linearly graded with no evidence of intrinsic layers. The C-V characteristics of two implanted diodes are presented in FIG. 2. The diodes were prepared identically except one was overcoated with AlN before anneal and the other Si 3 N 4 . In both cases the 1/C 3 vs. V curves are linear, which is characteristic of linear graded junctions. Slope calculations yield a grading of 2.5×10 22 /cm 4 for the AlN sample (Te-6) and 4.5×10 22 /cm 4 for the Si 3 N 4 specimen (Te-1). The results for other samples are summarized in Table I. It is interesting to note that there is no large discrepancy in the grading values between the AlN overcoated samples and the Si 3 N 4 covered samples.
The surface carrier concentration, sheet resistivity, and effective mobility in the implanted layers are listed in Table I. The electrical activity ranges from a few percent up to 45%, with the AlN overcoated samples generally having higher activities than the Si 3 N 4 coated samples. In addition, the AlN overcoated samples have N s values that increase with increasing dose, while the Si 3 N 4 values show some scatter.
The carrier concentration and mobility profiles for an implanted sample overcoated with Si 3 N 4 are shown in FIG. 3. Sequential Hall measurements in conjunction with layer removal were used to determine the carrier profile to a depth within a 1000A of the implanted junction. Slope analysis of the capacitance-voltage data (FIG. 2) produced a carrier concentration profile referenced to the junction depth and the substrate doping level. By using the SEM value of 2200A as the junction depth and a substrate doping of 2.3×10 17 holes/cm 3 , the C-V data were coupled with the differential Hall effect data to generate a carrier concentration profile extending from the surface to the junction depth. A consistent match of C-V carrier profile (open circles) to the Hall effect carrier profile (closed circles) is seen.
FIG. 4 presents the profile of an identical implant as shown in FIG. 3 except for processing with an AlN overcoat. In this case, this Hall effect profile and C-V profile were matched by slope without the aid of a junction depth measurement. The carrier profile exhibits a significantly higher peak election concentration than that of the previous sample. The peak value of 7×10 18 electrons/cm 3 is about equal to the maximum electron concentration which has been attained by doping GaAs with tellurium during growth. In addition, the deeply penetrating component of the carrier concentration is not as pronounced as that of the Si 3 N 4 overcoated sample.
TABLE I__________________________________________________________________________Summary of the Electrical Properties of Tellurium Implanted GaAsImplant Surface Carrier Effective Junction ForwardSampleDose Anneal Concentration Mobility GradingV Slope(b)No. (cm.sup.-2) Overcoat (cm.sup.-2) (cm.sup.2 /V-sec) (cm.sup.-4) (n)__________________________________________________________________________Te-4 3×10.sup.13 (a) Si.sub.3 N.sub.4 6.6×10.sup.12 1984 2.3×10.sup.22 1.16Te-2 1×10.sup.14 (a) Si.sub.3 N.sub.4 7.2×10.sup.12 1389 -- --G-74 1×10.sup.14 Si.sub.3 N.sub.4 2.0×10.sup.13 1498 3.1×10 1.15G-80 1×10.sup.14 Si.sub.3 N.sub.4 1.3×10.sup.13 1350 -- --Te-1 3×10.sup.14 Si.sub.3 N.sub.4 1.2×10.sup.13 1538 4.5×10.sup.22 2.0Te-3 3×10.sup.13 (a) A1N 1.8×10.sup.13 1664 2.7×10.sup.22 1.18Te-5 1×10.sup.14 (a) AlN 3.1×10.sup.13 1371 2.9×10.sup.22 1.21 Te-191×10.sup.14 (a) A1N 2.6×10.sup.13 1158 -- --Te-6 3×10.sup.14 A1N 4.0×10.sup. 13 1166 2.5×10.sup.22 1.16__________________________________________________________________________ (a)For these samples, an additional implant was made at 60 keV with a dos one-third of the 220 keV dose given. (b)1=1.sub.o exp(qV/nkT).
The comparison between sputtered AlN and Si 3 N 4 as an annealing overcoat or cap on implanted GaAs shows that the method of this invention provides an effective and efficient means for forming submicron layers of tellurium in a gallium arsenide substrate. The maximum electrical activity achieved using a sputtered AlN overcoat is comparable to the maximum value previously attained using a sputtered Si 3 N 4 overcoat. However, AlN has adherence properties that make it preferable to Si 3 N 4 . Also, the masking qualities of AlN are less sensitive to oxygen incorporated in the dielectric layer than Si 3 N 4 . Such integrity is essential for device fabrication.
In summary, the implantation of tellurium has been shown to create submicron n-type layers in GaAs with electron concentrations approximately equal to the maximum attainable in tellurium doped GaAs (˜10 19 electrons/cm 3 ) implanted junctions were linearly graded with no evidence of an intrinsic region.
Although the invention has been described with reference to a particular embodiment, it will be understood to those skilled in the art that the invention is capable of a variety of alternative embodiments within the spirit and scope of the appended claims.
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A method for forming tellurium N-type layers in gallium arsenide by using ion implantation as the doping process and aluminum nitride as a protective overcoat to prevent disassociation of the gallium arsenide during anneal.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to the field of collaborative computing and more particularly to workspace configuration in a collaborative computing environment.
[0003] 2. Description of the Related Art
[0004] Collaborative computing refers to the management and use of a computing environment in which individual end users collaborate with one another by sharing conversations, content and scheduled events and tasks to achieve a common goal. Generally, collaborative computing environments provide for multiple different communicative mechanisms such as e-mail and instant messaging. Further, collaborative computing environments often include calendaring and scheduling capabilities along with access to content browsing, shared discussion forums, shared document libraries and the like. In all, collaborative computing environments have proven a valuable computing resource in promoting team collaboration within the enterprise.
[0005] The collaborative workspace provides access the functionality of a collaborative computing environment. The workspace can vary widely from a limited user interface in a pervasive device to a robust portal interface in a more traditional computing device such as a personal computer. In all cases, however, the workspace can provide different command and control and display elements for each aspect of the collaborative computing environment. In particular, buddy and contact lists for e-mail and instant messaging, shared application views, database connections, file shares, network shares, file transfer protocol (FTP) locations, content bookmarks and look ahead caches can be rendered accessible from within the workspace.
[0006] One of the greatest challenges in a collaborative environment is the ability of a collaborator to determine relevant sources of information and to retrieve information from relevant sources in a timely manner in order to become productive. It often takes weeks if not months for a person to gather all relevant information needed to understand the subject space of a collaborative team to become productive. Such information can include the correct members for a buddy list, the relevant contacts in a contact list, pertinent database applications and needed database connections, relevant file shares, network shares, FTP locations, common team or organizational bookmarks, and suitably populated look-ahead caches. The configuration of the workspace can be pivotal in addressing this challenge.
[0007] Yet, given the relative complexity of the workspace for a collaborative computing environment, configuring a workspace can be a daunting task. For many users, the process of properly configuring a workspace can unfold over an extended period of time in fits and starts. Thus, integrating a new user into a collaborative environment can be challenging for the new user as the workspace must be configured rapidly to provide access to important buddy and contact lists, shared application views, database connections, file shares, network shares, FTP locations, content bookmarks and look ahead caches. Without a proper workspace configuration, the new user will be unable to fully participate as a collaborator and the intent and advantage of collaborative computing will be defeated.
BRIEF SUMMARY OF THE INVENTION
[0008] Embodiments of the present invention address deficiencies of the art in respect to collaborative computing and provide a novel and non-obvious method, system and computer program product for autonomically configuring a workspace in a collaborative computing environment. In an embodiment of the invention, a method for autonomically configuring a workspace in a collaborative computing environment can be provided. The method can include identifying a subject user and corresponding workspace in the collaborative environment, locating within a social network a related user for the subject user, retrieving a workspace configuration for the related user, and applying the workspace configuration to the corresponding workspace of the subject user.
[0009] In one aspect of the embodiment, locating within a social network a related user for the subject user can include locating a user sharing a common group in the social network with the subject user. In another aspect of the embodiment, retrieving a workspace configuration for the related user can include retrieving a workspace configuration for the related user, and filtering from the workspace configuration private workspace configuration elements leaving shareable workspace configuration elements in the workspace configuration. In yet another aspect of the embodiment, the method further can include identifying a different user and corresponding workspace in the collaborative environment, locating within the social network related users for the different user, retrieving corresponding workspace configurations for each of the related users, computing either a union or an intersection of configuration elements for the corresponding workspace configurations, and applying the union or intersection of the configuration elements as a configuration for the corresponding workspace of the different user.
[0010] Additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The aspects of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention. The embodiments illustrated herein are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown, wherein:
[0012] FIG. 1 is a pictorial illustration of a process for autonomic workplace establishment;
[0013] FIG. 2 is a schematic illustration of a collaborative computing data processing system configured for autonomic workplace establishment; and,
[0014] FIG. 3 is a flow chart illustrating a process for autonomic workplace establishment.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Embodiments of the present invention provide a method, system and computer program product for autonomic workplace establishment in a collaborative computing environment. In accordance with an embodiment of the present invention, the workplace for a collaborative computing environment can be associated with a subject user. A relationship between the subject user and a related user as expressed within a social network, for example by group membership, can be identified within the social network and the workplace configuration for the workplace of the related user can be retrieved and applied to the workplace of the subject user. In this way, the workplace of the subject user can be autonomically configured through the inference that the configuration of two related users of the collaborative computing environment ought to be similar.
[0016] In illustration, FIG. 1 pictorial depicts a process for autonomic workplace establishment. As shown in FIG. 1 , a new workspace 120 A for a new user 110 A can be initialized for configuration. In response, a related user 110 B can be located within a social network 170 for the new user 110 A. For example, the related user 110 B can share common group membership in the social network 170 as the new user 110 A. Alternatively, the new user 110 A can manually select or otherwise specify the related user 110 B. In any event, the workspace configuration 160 for the workspace 120 B of different buddy and contact lists 130 , content bookmarks 140 , and shared application views, database connections, look ahead caches, file shares, network shares and FTP locations 150 , can be forwarded and applied to the new workspace 120 A so as to autonomically configure the new workspace 120 A of the new user 110 A without requiring the new user 110 A to manually select configuration elements for the new workspace 120 A.
[0017] The process illustrated in FIG. 1 can be implemented in a collaborative computing data processing system. In further illustration, FIG. 2 schematically depicts a collaborative computing data processing system configured for autonomic workplace establishment. The system can include a host server 230 configured for communicative coupling to multiple different collaborative clients 210 over a computer communications network 240 , each client 210 supporting the operation of a collaborative client workspace 220 . Of note, each workspace 220 can be configured separately according to the preferences of a collaborative end user interacting with the workspace 220 .
[0018] The host server 230 can host the operation of a collaborative computing system 270 servicing the collaborative clients 210 and providing content for the respective workspaces 220 . The collaborative computing system 270 further can manage the individual configurations 260 for corresponding ones of the workspaces 220 in the collaborative clients 210 . In this regard, each of the configurations 260 can specify for a corresponding one of the workspaces 220 , different buddy and contact lists, content bookmarks, and shared application views, database connections, look ahead caches, file shares, network shares and FTP locations, to name a few examples.
[0019] Importantly, autonomic workspace establishment logic 250 can be provided. The logic 250 can be coupled to the host server 230 either directly as part of the collaborative computing system 270 or remotely through an application programming interface (API) of the collaborative computing system 270 . Optionally, the logic 250 can be incorporated into the collaborative clients 210 . The logic 250 can include program code enabled to configure one of the workspaces 220 with a configuration 260 of another of the workspaces 220 . The configuration 260 can be selected based upon a relationship between the collaborative users associated with each of the workspaces 220 . The relationship can be determined through a coupled social network 200 B executing in supporting server 200 A.
[0020] For example, the configuration 260 can be selected based upon a relationship of common group in the social network 200 B between the collaborative users. Alternatively, multiple different configurations for correspondingly different related users can be merged into a single configuration either by taking the intersection or the union of the elements of each configuration. Yet as a further alternative, the configuration of a user at a higher level in an organizational hierarchy can apply a corresponding configuration to a user at a lower level in the hierarchy.
[0021] In yet further illustration of the operation of the autonomic workspace establishment logic 250 , FIG. 3 is a flow chart illustrating a process for autonomic workplace establishment. The process of FIG. 3 can be performed automatically upon launching a workspace for a collaborative user, or manually at the request of an end user or an administrator. Beginning in block 310 , a role, team or group can be identified for a subject user which can be a new user to a collaborative environment or an existing user seeking to configure a corresponding workspace. In block 320 , one or more related users sharing a common group or similar interests as expressed in a social network can be identified and a particular one of the related users can be selected for processing.
[0022] In block 330 , the configuration for the related user can be retrieved. The configuration can include, by way of example, collaborative workspace elements including different buddy and contact lists, content bookmarks, and shared application views, database connections, look ahead caches, file shares, network shares and FTP locations. In block 340 , the configuration can be filtered to remove elements of the configuration determined to be private. In this regard, each user in the collaborative computing environment can mark different configuration elements private or shareable. Alternatively, access control rules can specify which configuration elements can be shared with other users according to role or group membership, for instance. In any case, thereafter, the filtered configuration elements can be applied to the workspace of the subject user in block 350 thereby autonomically configuring the end user workspace.
[0023] Embodiments of the invention can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software, microcode, and the like. Furthermore, the invention can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer or any instruction execution system.
[0024] For the purposes of this description, a computer-usable or computer readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Examples of a computer-readable medium include a semiconductor or solid state memory, magnetic tape, a removable computer diskette, a random access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk—read only memory (CD-ROM), compact disk—read/write (CD-R/W) and DVD.
[0025] A data processing system suitable for storing and/or executing program code will include at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution. Input/output or I/O devices (including but not limited to keyboards, displays, pointing devices, etc.) can be coupled to the system either directly or through intervening I/O controllers. Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.
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Embodiments of the present invention address deficiencies of the art in respect to collaborative computing and provide a method, system and computer program product for autonomically configuring a workspace in a collaborative computing environment. In an embodiment of the invention, a method for autonomically configuring a workspace in a collaborative computing environment can be provided. The method can include identifying a subject user and corresponding workspace in the collaborative environment, locating within a social network a related user for the subject user, retrieving a workspace configuration for the related user, and applying the workspace configuration to the corresponding workspace of the subject user.
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BACKGROUND OF THE INVENTION
This invention relates to a platform of the gravity type, that is, one maintained by virtue of its own weight on the bottom of a body of water, and more particularly to an offshore platform lying on the bottom of a shallow body of water.
Conventional offshore platforms include a structure, usually in the form of a tower, which has a base resting on the bottom and which supports, above the surface of the water, a bridge which in turn supports industrial or scientific installations, an example being equipment for drilling or extraction operations on hydrocarbon wells.
The building of such a platform requires a vast construction site and involves long and complicated operations. Further, such offshore platforms are not extendable, and consequently if the forecasts made at the time a platform was built are exceeded, the original platform must either be replaced by a larger one or have a second one connected to it.
SUMMARY OF THE INVENTION
It is one object of this invention to provide a platform which is readily extendable. Another object is to provide a platform having a construction which requires only a location of moderate size and involves simple and relatively rapid operations. Still another object is to provide a platform capable of being built up from prefabricated elements which can consequently easily be produced in prestressed concrete.
A platform according to this invention includes a plurality of longitudinally disposed bays supported by piers, each consisting of a small number of transversely aligned posts resting on a common base and supporting a cross-beam, each bay having a framework of longitudinal beams resting at either end on the cross-beam. Preferably, the framework additionally includes transverse joists which, together with the longitudinal beams, form a latticework which can be at least partly covered with flooring or flooring elements.
The present invention further relates to a construction method which includes the steps of preparing each pier onshore, transporting it to the site where it is to be set down and causing it to rest on the bottom, raising the base at various points and adjusting the heights thereof above the bottom of the water in order to position the base horizontally, securing the base in this horizontal position by pouring concrete beneath it, for example, preparing each bay on the shore and transporting it to the installation site, and thereafter setting it on two adjacent piers.
Preferably, the preparation of the piers includes the provisional fixing of the cross-beams on top of the posts and, prior to placement of the bays, the position of the cross-beams is so adjusted as to cause their upper surfaces to lie in the same horizontal plane, after which they are secured in position and fixed definitively to the posts in this position.
In order to enable them to be transported up to the installation site and set down on the bottom, the piers are preferably equipped with ballastable floats and are placed on an "over-immersible" barge, that is, a barge having a degree of immersion which can be varied by ballasting it to a lesser or greater extent. At the installation site, the barge is weighted so that it rides low enough in the water for the pier which it is carrying to begin to float, after which the barge is towed to the shore and the pier floats are ballasted to cause the pier to rest on the bottom. Both this particularity of the method and the "over-immersible" barge form part of the present invention.
Once the bays are in position, the platform can be equipped. Such equipment may include risers, namely pipes connecting the platform deck to the bottom. In order to protect these risers against shocks, recourse is preferably had to protective means comprising vertical casings through which extend stakes driven into the water bed. Assembly is effected by resting the protection on the bottom and using the casings as guides for driving in the stakes or for drilling holes into which the stakes are then engaged. Such protective means and its method of assembly likewise form part of this invention.
The description which follows with reference to the accompanying non-limitative exemplary drawings will give a clear understanding of how the invention can be carried into practice.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings,
FIG. 1 is a plan view of a platform made according to this invention;
FIG. 2 is a sectional view through the line II--II of FIG. 1;
FIG. 3 is a sectional view through the line III--III of FIG. 2;
FIG. 4 is a sectional view through the line IV--IV of FIG. 1;
FIG. 5 is a side elevation view showing the loading of a pier on an over-immersible barge;
FIG. 6 is an end view showing a pier floating and the barge in its over-immersed position;
FIG. 7 is a view corresponding to FIG. 3, showing on an enlarged scale the base of a pier equipped with levelling jacks;
FIG. 8 is a sectional view through the line VIII--VIII of FIG. 7, illustrating the levelling of the base;
FIG. 9 is a diagrammatic view on a different scale, illustrating the securing or wedging of the base;
FIG. 10 is a view corresponding to part of FIG. 4, illustrating on an enlarged scale the levelling and securing of a cross-beam;
FIG. 11 is a sectional view through the line XI--XI of FIG. 10;
FIG. 12 is a view corresponding to FIG. 2, on an enlarged scale, illustrating the positioning of a bay;
FIG. 13 is a plan view along the arrow XIII of FIG. 12; and
FIG. 14 is a view corresponding to FIG. 4, illustrating the assembly of protective means.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The platform shown in FIGS. 1 to 4 is an offshore platform resting on a seabed about twelve meters deep, for use in extraction operations from previously drilled oil-wells. It includes a bridge structure extending above the water surface and is composed of a plurality of bays 1, disposed longitudinally and supported by an underframe structure composed of piers 2, each of which is formed by three transversely aligned posts 3, 4, 5 resting on a common base 6 and supporting a cross-beam 7. Each bay 1 comprises a framework span made up of four longitudinal beams 8, 9, 10, 11 which, together with transverse joists 12, form a latticework which can be covered, at least partly, with flooring or flooring elements, such as elements 13. The longitudinal beams 8-11 of each bay 1 rest at either end on cross-beams 7 of two adjacent piers 2. The bay framework is intended to support production gear (pumps, separators, compressors, etc.) shown only partially on the drawings. Each bridge span or bay framework is a generally planar, i.e., substantially two-dimensional, horizontally oriented structure. Each pier 2 is a generally planar, i.e., substantially two-dimensional, vertically oriented structure.
The piers 2 are constructed on shore, preferably in a workshop, thus enabling them to be readily fabricated from prestressed concrete without the need for the complicated apparatus required to set the reinforcements under tension on a work-site. The posts 3, 4, 5 of each pier are fixed to the base 6 thereof, but cross-beam 7 is temporarily fixed to the tops of the posts. FIG. 5 illustrates the manner of loading a pier on an over-immersible barge 14 which includes (see also FIG. 6) a deck 15 supported by two tubular floats 16, 16a fixed at either end to a tubular U-shaped float 17 with upwardly extending arms. Ballasting means (not shown) enable water to be admitted into the floats 16, 16a and 17 or to be expelled therefrom in order to vary the degree of immersion of the barge 14. Pier 2 is equipped with floats 18 formed by hollow cylinders fixed vertically against the posts 3, 4, 5 and likewise comprising ballasting means (not shown), after which the pier 2 equipped thus is deposited on a quay 19 (the position shown in dash lines in FIG. 5). Barge 14 is moved against quay 19, after which its floats 16, 16a and 17 are filled with the amount of water required to bring its deck 15 level with quay 17. The pier 2 can then be slid onto deck 15 or caused to roll thereon on rollers (not shown). Barge 14 is then towed to the platform installation site, the floats 16, 16a and 17 are once more ballasted until barge 14 sinks low enough for pier 2 to be kept afloat by its floats 18, after which barge 14 is evacuated and towed to the shore to be loaded with another pier 2. Pier 2 is then moved vertically above its definitive location and the floats 18 are gradually ballasted until base 6 rests on the seabed 20. The U-shaped floats 17 protrude from the water when the barge is partially sunk (FIG. 6) and that the height of piers 2 is greater than the sea depth at the installation site, whereby floats 18 still rise above the surface 21 of the sea when base 6 rests on seabed 20 (see FIG. 4). The barge 14 and pier 2 equipped with its floats 18 thus float in stable fashion while the operations hereinbefore described are performed.
The seabed 20 is not as a rule very horizontal, and FIGS. 7, 8 and 9 illustrate means used to ensure that the pier 2 is nevertheless supported on the seabed 20 with its base 6 horizontal and the posts 3, 4, 5 consequently truly vertical. Hingedly connected to each end of base 6 are the cylinders 22a of four jacks 22; to the end of the rod 22b of each such jack is hingedly connected a supporting member 23 which includes a plate 23a the undersurface of which bears a spade 23b designed to anchor into the seabed. The periphery of base 6 is provided with rolls 24 onto which are rolled porous sheets 25, manufactured under the brand name Filter-X by the American firm, Carthage Mills Inc., Cincinnati, Ohio (United States), and distributed in France by the Sindic company, 16 rue Jean Mermoz, Paris. These sheets 25 are made of porous plastic material which retain particles with a dimension in excess of 0.088 mm in a turbulent water stream, and retain even finer particles in a laminar flow of water. Such porous sheets 25 are commonly used to allow the foundations of constructions on land to drain without causing undermining by water.
The jack cylinders 22a can be fed with hydraulic fluid through flexible lines (not shown) long enough to enable the jacks 22 to be actuated from the surface of the sea. After the base 6 has been set down on an inclined seabed (depicted schematically by reference numeral 20 in FIG. 9), the jacks 22 are operated from a craft (not shown) floating on the surface 21 of the water, in order to position the base 6 horizontally. A team of divers then unwinds the porous sheets 25 and secures their ends to the seabed 20, thereby to enclosing the space 26 between base 6 and seabed 20. Concrete is then injected into the space 26 through a pipe leading from the craft on the water surface 21. Porous sheets 25 allow any surplus water to drain from the concrete yet maintain the concrete in position until it has set, after which the jacks 22 can be recovered.
When all the piers 2 have been adjusted accordingly cross-beams 7 will be properly horizontal but not at the same level as a rule. The upper faces of posts 3 and 5 are formed with symmetrical indents 27 and 28 respectively (see FIGS. 10 and 11), and disposed in each of these indents 27 and 28 is a hydraulic jack 29 which acts between the bottom of the indent 28 and the undersurface 7a of cross-beam 7. Accordingly the temporary attachments (not shown) joining beam 7 to the tops of the posts 3-5 are removed and the jacks 29 are activated by means well known per se (not shown) in order to set the upper surfaces 7b of all the cross-beams 7 in the same horizontal plane. Thereafter, the cross-beams 7 are maintained in this position by means of wedges 30, the jacks 29 are removed for further use, and cross-beam 7 is positively fixed to the tops of the posts 3-5, for instance, by injecting concrete, as depicted in dashed lines at the top of post 5.
The bays 1 are fabricated on shore, for example, from prestressed concrete like the piers 2, after which each bay 1 is set down on the quay 19 (a position not shown) and thereafter pushed from there onto a trellis support 31 placed on a barge 32 equipped with ballastable floats (not shown) for adjusting its degree of immersion (see FIGS. 12 and 13). The bay 1 is placed transversely on barge 32, the width of which barge 32 is less than the inner gap between two adjacent piers 2, whereby the ends of the bay 1 project from either side of the barge 32. The barge 32 is towed to the installation site, its degree of immersion is adjusted so that the undersurfaces of longitudinal beams 8, 9, 10, 11 are at a slightly higher level than that of the upper surfaces 7b of cross-beams 7, the barge 32 is maneuvered between the two adjacent piers 2 so that bay 1 is placed above its ultimate resting position, and thereafter the barge 32 is ballasted so that the bay 1 comes to rest on cross-beams 7 in that position, after which the barge 32 can be disengaged and towed to shore to load another bay 1.
After construction of the platform has been completed, the floorings or partial floorings 13 are laid and the platform is equipped. Such equipment is represented only on the right-hand bay 1 in FIGS. 1 and 2 and is shown as including risers 33 (that is, tubes connecting the platform deck to the seabed 20). These risers 33 are protected by means 34 formed by trellis-work bars 32a interconnecting vertical casings 35 through which extend stakes 36 driven into the seabed 20. FIG. 14 illustrates the manner of assembling the protective means 34, which manner comprises the steps of setting the trellis-work bars 34a on the seabed 20 vertically in line with the location it is to occupy, drilling holes 37 into the seabed 20 with rods 38 driven by gear 39 cantilevered from the bridge of the platform and movable therealong, driving the stakes 36 (see FIG. 2 again) into the holes 37, raising the assembled trellis-work bars 34 level with the water surface 21, and securing the bars 34a in that position.
Changes and substitutions of parts may be made to the form of the embodiment, hereinbefore described by way of example, without departing from the scope of the invention. More specifically, instead of using a variable-immersion barge 32 as shown in FIG. 12, a barge equipped with lifting means or jacks for adjusting the level of bays 1 may be used.
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A platform resting at the bottom of a body of water, including a plurality of longitudinally disposed bays supported by piers each consisting of a small number of transversely aligned posts resting on a common base and each supporting a cross-beam, each bay comprising a framework of longitudinal beams which rest at either end on the cross-beams, and a method of constructing the platform comprising the steps of preparing each pier onshore, transporting it to the installation site and setting it down on the bottom, raising the base at several points and adjusting their heights above the bottom in order to position the base horizontally, securing the base in that position by pouring concrete beneath it, preparing each bay on the shore, transporting it to the installation site and setting it down on two adjacent piers.
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This application is a continuation of U.S. patent application Ser. No. 08/681,527, filed Jul. 22, 1996 now U.S. Pat. No. 5,787,097.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the testing of integrated circuit (IC) memories, and more particularly, to IC memories having circuitry which, during a test mode of operation, compresses the number of output data bits to fewer than the number of data bits used during the normal mode of operation.
2. Description of the Related Art
As the geometries and cost of integrated circuit memories continues to be reduced, the costs associated with testing the memories is becoming a more significant component of the total manufacturing cost. Specifically, before delivery to end users, each memory chip must be tested to ensure that it is functioning properly.
For example, referring to FIG. 1, a memory chip 20 having 16 data lines DQ[15:0] is connected to a memory chip tester 22 that has at least 16 I/O lines I/O[15:0]. A common testing procedure is to first have the tester 22 send a command to the memory chip 20 to erase all of its bits to "1". The tester 22 then reads the data lines DQ[15:0] in order to verify that they are all "1". Next, zeros are written to all of the bits of the memory chip 20 and the data lines DQ[15:0] are read in order to verify that they are all "0". Then, all of the bits of the memory chip 20 are erased, a checker board pattern "0101010101010101" is written to the memory chip 20, and the data lines DQ[15:0] are read in order to verify that the checker board pattern is present on the data lines. Finally, all of the bits of the memory chip 20 are erased, an inverted checker board pattern "1010101010101010" is written to the memory chip 20, and the data lines DQ[15:0] are read in order to verify that the inverted checker board pattern is present on the data lines. This testing procedure is a good way to find out if any of the bits of the memory chip 20 are shorted to an adjacent bit, to a high level or to a low state, or if there are any other problems.
Memory testers have a limited number of I/O pins, e.g., 32, 64, 128, etc. When memory chips are connected to a tester in the manner shown in FIG. 1, a memory tester having 64 I/O pins can simultaneously test four, 16 bit memory chips. This is because each one of the four memory chips requires 16 of the tester's I/O lines in order for the tester to separately read each of the four memory chips.
Because the cost of testing is becoming such a significant component of the total manufacturing cost of memory chips, it would be desirable to somehow increase the number of memory chips which can be simultaneously tested with a single tester so as to reduce the per chip cost of testing.
SUMMARY OF THE INVENTION
The present invention provides a memory system operable in a normal mode of operation and a test mode of operation. The memory system includes sensing circuitry which generates x number of data bits during a read cycle. A detection circuit detects a first pattern among the x number of data bits. An output circuit generates y number of output data bits, which is less than the x number, which are arranged in a second pattern which is indicative of the first pattern detected by the detection circuit. A read path circuit, coupled to the sensing circuitry, the detection circuit and the output circuit, transfers the x number of data bits to x number of output nodes in a first read cycle operating in the normal mode of operation. The read path circuit also transfers the y number of output data bits to y number of output nodes in a second read cycle operating in the test mode of operation.
The present invention also provides a memory system operable in a normal mode of operation and a test mode of operation. The memory system includes sensing circuitry which generates x number of data bits during a read cycle. A read path circuit, coupled to the sensing circuitry, transfers the x number of data bits generated by the sensing circuitry during a first read cycle in the normal mode of operation to x number of output nodes. A first detection circuit, coupled to the read path circuit, detects whether or not the x number of data bits generated by the sensing circuitry during a second read cycle in the test mode of operation are arranged in a pattern in which all bits are identical. A second detection circuit, coupled to the read path circuit, detects whether or not the x number of data bits generated by the sensing circuitry during the second read cycle in the test mode of operation are arranged in a pattern in which each two adjacent bits are different. An output circuit, coupled to the first and second detection circuits, generates y number of output data bits which are arranged in a pattern indicative of whether the x number of data bits generated by the sensing circuitry during the second read cycle in the test mode of operation are identical, are arranged in a pattern in which each two adjacent bits are different, or are arranged in another pattern, and wherein y is less than x.
The present invention also provides a pattern recognition circuit which includes a first detection circuit which detects whether or not a set of x number of data bits are arranged in a pattern in which all of the x number of data bits are identical and which generates a MATCH signal in response thereto. An output circuit, coupled to receive the MATCH signal, generates y number of output data bits which are arranged in a pattern indicative of whether the set of x data bits are identical or are arranged in another pattern, wherein the y number is less than the x number.
The present invention also provides a method of testing an integrated circuit (IC) memory. The method includes the steps of: reading x number of outputs of sensing circuitry in the IC memory so that x number of data bits are read; detecting a first pattern among the x number of data bits which are read; and generating a y number of output data bits which is less than the x number and which are arranged in a second pattern which is indicative of the first pattern among the x number of data bits.
The present invention also provides a memory system operable in a normal mode of operation and a test mode of operation. The memory system includes sensing circuitry which generates x number of data bits during a read cycle. A detection circuit detects a first pattern among the x number of data bits. An output circuit generates y number of output data bits, which is less than the x number, which are arranged in a second pattern which is indicative of the first pattern detected by the detection circuit. An x number of output drivers correspond to the x number of data bits generated by the sensing circuitry. During the test mode of operation only y number of the x number of output drivers are enabled and are used to transfer the y number of output data bits to y number of output nodes.
The present invention also provides a memory test system which includes a memory tester and a plurality of memories coupled to the memory tester. Each of the memories includes x number of output nodes, sensing circuitry configured to generate x number of data bits, and a compression circuit operatively coupled to the sensing circuitry and configured to compress the x number of data bits to a lower y number of output bits so that data represented by the x number of data bits can be represented on only y number of the x number of output nodes.
A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description of the invention and accompanying drawings which set forth an illustrative embodiment in which the principles of the invention are utilized.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram illustrating a prior art memory chip connected to a memory chip tester.
FIG. 2 is a block diagram illustrating memory chips in accordance with the present invention connected to a memory chip tester.
FIG. 3 is a schematic diagram illustrating a prior art memory chip read path.
FIG. 4 is a schematic diagram illustrating a memory chip read path in accordance with the present invention.
FIG. 5 is a schematic diagram illustrating the pattern recognition block shown in FIG. 4.
FIG. 6 is a schematic diagram illustrating one embodiment of one of the detection blocks shown in FIG. 4.
FIG. 7 is a schematic diagram illustrating one embodiment of the other detection block shown in FIG. 4.
FIG. 8 is a schematic diagram illustrating another embodiment of the detection blocks shown in FIG. 4.
FIG. 9 is a schematic diagram illustrating a circuit for a detector/decoder which can be incorporated into the memory chips shown in FIG. 2 and used for entering the I/O compression test mode of operation.
FIG. 10 is a functional block diagram illustrating a memory system which includes the I/O compression pattern recognition block shown in FIG. 4 and the detector/decoder shown in FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 2, there is illustrated four memory chips 24, 26, 28, 30 in accordance with the present invention. In general, in order to maximize the number of parts that can be tested in parallel, i.e., simultaneously, by the tester 22, each of the memory chips 24, 26, 28, 30 is placed in a special I/O compression test mode in which the number of active output pins on the memory chips 24, 26, 28, 30 is reduced and the remaining output drivers are tri-stated. In other words, when the memory chip 24 is in the I/O compression test mode and is being read, i.e., the memory chip 24 is outputting data, fewer than all of its 16 data pins are active.
As will be discussed below, circuitry inside each of the memory chips 24, 26, 28, 30 which is enabled during the I/O compression test mode "compresses" the data which is normally output on all 16 data pins down to fewer than 16 data pins. During the I/O compression test mode, the active output drivers output a pre-processed data that make it possible for a tester to verify the pass/fail status of specific patterns at different address locations. Thus, when the memory chip 24 is tested, information which is normally represented on all 16 of the data pins during the normal user mode of operation is represented on fewer than 16 pins during the I/O compression test mode. Using this compressed data, the tester is still able to extract enough information to detect failing patterns. It should be noted that the data compression takes place only when the data pins of the memory chips 24, 26, 28, 30 are in the output mode. When the memory chips 24, 26, 28, 30 are being written to, i.e., their data pins are in the input mode, all of the data pins DQ[15:0] remain active (except for program command purposes, which will be discussed below).
As mentioned above, I/O compression takes place during a special test mode of operation which is not a normal user mode of operation. One method for placing the memory system into a test or special mode of operation is described in U.S. Pat. No. 5,526,364, entitled, "Apparatus for Entering and Executing Test Mode Operations for Memory", granted Jun. 11, 1996, the contents of which is hereby incorporated in full by reference.
FIG. 9 is a schematic of a circuit for a detector/decoder (see element 102 of FIG. 10) which can be incorporated into a memory system and used for entering the I/O compression test mode of operation. In order to place the memory system into such a test mode of operation, the test mode must be entered and the appropriate test mode command signals must be applied to the data I/O terminals of the memory.
Typically, the end user of the memory system would have no reason to cause the memory system to enter a test or special mode of operation since this mode is intended to be used by test engineers at the memory fabrication facility. Furthermore, accidental entry into such a mode is to be avoided since the memory could be rendered permanently inoperable in this mode. Thus, the test mode entry circuitry of FIG. 9 is designed to reduce the likelihood of accidental entry into the mode by requiring simultaneous application of high voltages to multiple memory system terminals.
The circuit of FIG. 9 is activated by application of a high voltage to two or more terminals 700 and 702 of the memory system from an external source. These terminals are non-dedicated terminals used during normal memory operations. Terminals 700 and 702 may include, for example, address terminal (pad) A10 and the write enable terminal WE. The magnitude of the high voltage applied to terminals 700 and 702 is chosen to be outside of the range of voltages which would typically be applied to those terminals during use of the terminals in normal (non-test mode) operation of the memory system. This is done to prevent an end user from unintentionally entering the test or special mode. The high voltage applied to terminals 700 and 702 is detected by detectors 706 and 708. A detector circuit suited for use in constructing detectors 706 and 708 is described in U.S. patent application Ser. No. 08/493,162, entitled, "Integrated Circuit Having High Voltage Detection Circuit", filed Jun. 21, 1995, the contents of which is hereby incorporated in full by reference.
After application of the high voltage to terminals 700 and 702, a signal on another terminal 710, in this case the chip enable CE terminal, is made active (low). Code signal data corresponding to one of several possible test or special modes is placed on the data I/O terminals 712 of the memory system and forwarded to an I/O buffer 714. In the present case, code data corresponding to an I/O compression test mode would be input.
An AND gate 716 provides a test mode load enable signal when the outputs of both high voltage detectors 706 and 708 indicate that an appropriate high voltage is being applied to terminals 700 and 702. The load enable signal is coupled to one input of an AND gate 718 together with an inverted signal CE. This causes AND gate 718 to turn on pass transistor 720 which forwards the test or special mode code data entered by means of I/O pads 712 to buffer 714 and then to a test mode code latch 722. Separate I/O terminals and pass transistors 720 are used for each bit of input test or special mode data so that the data will be loaded into latch 722 in parallel. Typically there are a total of eight bits of test code data so that latch 722 will contain eight bits. Signal CE is then brought back to a high state, thereby latching the code data in latch 722.
After latch 722 has been loaded with the code data, one of the high input voltages, such as the input to address A10 terminal 702 is removed so that the output of detector 708 will go low thereby providing a high input to an AND gate 730 by way of inverter 728. Since the remaining input of gate 730, the output of the second high voltage detector 706, will still be high, gate 730 will produce a test or special mode enable signal. Among other things, this will enable a Test Mode and Format Check and Decode Logic unit 724 which will verify that the data in latch 722 corresponds to a proper test or special mode. In addition, unit 724 will decode the mode code to determine which one of approximately fifteen different special or test modes has been entered. These modes each have an associated mode signal which is produced by the Test Mode and Format Check and Decode Logic unit 724 and which is used by the memory system in combination with other signals for carrying out the various test or special mode functions.
The system will remain in the selected mode as long as the voltage applied to terminal 700 remains high. When signal CE is brought back to a high state, detector activation logic 732 keeps detector circuits 704 and 706 enabled as long as the voltage applied to terminal 700 remains high. During the course of carrying out the various test or special mode operations, it may be necessary to periodically change the state of the chip enable CE signal. However, since address A10 on line 702 has been shifted to a low state, the low output of AND gate 718 will prevent any change in the contents of mode code latch 722. Once the test or special mode of operation is completed, the high voltage applied to terminal 700 is removed, thereby causing the output of AND gate 730 to go low and end the test or special mode of operation.
The test mode codes loaded into latch 722 are preferably of a specific format which further reduces the possibility of accidental entry into a test mode. The mode code is typically divided into two groups of bits, with the first group of bits, the format bits, signifying a test or special mode of operation and the remaining bits signifying a particular one of the modes. A description of a code format suited for use with the present invention can be found in the previously mentioned U.S. Pat. No. 5,526,364.
In the embodiment of the invention described herein, the number of output pins in the memory chips 24, 26, 28, 30 which remain active during the I/O compression test mode are the 4 data pins DQ[7:4]. This permits the four 16 bit memory chips 24, 26, 28, 30, rather than just the single memory chip 20 shown in FIG. 1, to be simultaneously tested by the single tester 22 having 16 I/O pins. Four data pins were chosen because certain flash memory chips, such as the memory chips 24, 26, 28, 30, require at least 4 I/O pins to pass the basic write commands, such as for example, program, erase, erase suspend and status read. Furthermore, 4 I/O pins are needed to monitor the status register in each of the memory chips 24, 26, 28, 30 during write operations. It should be well understood, however, that the number of active output pins on the memory chips 24, 26, 28, 30 may be reduced to a number greater than or less than 4 in accordance with the present invention. A general principle of the present invention is that, during a test mode, the number of active output pins on a memory chip, regardless of the total number of output pins on the memory chip, is reduced to a number less than the total number. For example, it is envisioned that the number of active output pins on a memory chip could be reduced to just 2 pins. By reducing the number of active output pins, a greater number of memory chips can be connected to and simultaneously tested by a single tester.
In order to simplify the following discussion, it will be assumed that the tester 22 has only 16 I/O pins I/O[15:0]. However, it should be well understood that the principles of the present invention apply to memory chip testers having any number of I/O pins. For example, for the scenario discussed herein where a memory chip has 4 active outputs during I/O compression test mode, a tester having 32 I/O pins could simultaneously test eight 16 bit memory chips, a tester having 64 I/O pins could simultaneously test sixteen 16 bit memory chips, etc.
The memory chips 24, 26, 28, 30 are connected to the tester 22 by connecting the active output pins DQ[7:4] of each memory chip 24, 26, 28, 30 to separate I/O pins on the tester 22, as shown. Such a connection gives the tester 22 the ability to simultaneously read the data on the active output pins DQ[7:4] of each memory chip 24, 26, 28, 30.
The other pins DQ[3:0, 15:8] of each memory chip 24, 26, 28, 30 are connected to the remaining pins of the tester 22 for which no connection has been made for that particular memory chip. For example, with respect to the memory chip 24, as shown in the dashed lines in FIG. 2, the data pins DQ[3:0] are connected to the I/O pins I/O [15:12], the data pins DQ[11:8] are connected to the I/O pins I/O [7:4], and the data pins DQ[15:12] are connected to the I/O pins I/O [11:8]. Although not shown in FIG. 2 in order to simplify the drawing, similar connections are made to each of the other memory chips 26, 28, 30.
Such connections result in each I/O pin of the tester 22 being connected to more than one memory chip; e.g., four memory chips in the scenario shown in FIG. 2. This is not a problem, however. Specifically, during a write operation, i.e., the tester 22 is writing to the memory chips 24, 26, 28, 30, it is permissible for each I/O pin of the tester 22 to write to more than one of the memory chips 24, 26, 28, 30. However, during a read operation, i.e., the tester 22 is reading the memory chips 24, 26, 28, 30, each I/O pin of the tester 22 can read only one pin of one of the memory chips 24, 26, 28, 30. Because during a read operation, as discussed above, only the data pins DQ[7:4] of each memory chip 24, 26, 28, 30 are active, and the data pins DQ[7:4] of each memory chip 24, 26, 28, 30 are connected to separate I/O pins on the tester 22, each I/O pin of the tester 22 is in fact reading only one pin of one of the memory chips 24, 26, 28, 30. Again, during a write operation, all of the data pins DQ[15:0] of each memory chip 24, 26, 28, 30 are active, but during a read operation, only the four data pins DQ[7:4] of each memory chip 24, 26, 28, 30 are active.
It should be noted that a write operation is preceded by a four bit program command. As mentioned above, when in the I/O compression test mode all of the data pins DQ[15:0] of each of the memory chips 24, 26, 28, 30 are active during a write operation. However, in the I/O compression test mode, only the data pins DQ[7:4] of each of the memory chips 24, 26, 28, 30 are active for program command purposes. This is because in the normal user mode of operation the memory chips 24, 26, 28, 30 receive program commands in data pins DQ[7:4] and data pins [15:8, 3:0] are all "0". In the I/O compression test mode scenario shown in FIG. 2, however, the tester 22 will send out the same program command on each set of the four sets of output lines I/O [3:0], I/O [7:4], I/O [11:8], I/O [15:12] so that each of the memory chips 24, 26, 28, 30 receives the program command at its data pins DQ[7:4]. But due to the connections shown in FIG. 2, the other data pins DQ[15:8, 3:0] of each of the memory chips 24, 26, 28, 30 will also receive the program command. Therefore, in the I/O compression test mode, the memory chips 24, 26, 28, 30 will look only at the data pins DQ[7:4] for program command purposes so that the program commands are properly received.
FIG. 3 shows a typical read path 32 for a conventional memory chip, such as the memory chip 20 shown in FIG. 1. During a normal array read operation, i.e., when an external device connected to DQ[15:0] is reading the memory, the RD signal is switched to "1" in order to turn on the pass gates M2[15:0] and the RDSTAT signal is switched to "0" in order to turn off the pass gates M4[15:0]. Data is passed from the sense amplifiers 34 to the output drivers 36, which are enabled by the enable signal OE. During a status register read operation, the RD signal is switched to "0" in order to turn off the pass gates M2[15:0] and the RDSTAT signal is switched to "1" in order to turn on the pass gates M4[15:0]. Status data is passed from the status lines Status[15:0] to the output drivers 36.
FIG. 4 shows a read path 38 in accordance with the present invention which is embodied in each of the memory chips 24, 26, 28, 30. The read path 38 includes the circuitry which compresses the data which is normally output on all 16 data pins down to fewer than 16 data pins during the I/O compression test mode. The read path 38 has a pattern recognition block 40 added across the pass gates M2[15:0]. The purpose of the pattern recognition block 40 is to receive the data sendat[15:0] which comes from the sense amplifiers 34 and compress that data down to 4 bits. Although the output CMPOUT[15:0] of the pattern recognition block 40 is 16 bits wide, the result of the compression performed by the pattern recognition block 40 is embodied in the 4 bits CMPOUT[7:4]. These 4 bits are inverted and then output on the 4 active output pins DQ[7:4]. The CMP signal enables the pattern recognition block 40.
During a normal array read operation the RD signal is switched to "1" in order to turn on the pass gates M2[15:0], and the RDCMP and RDSTAT signals are switched to "0" in order to turn off the pass gates M3[15:0], M4[15:0]. During a status register read operation, the RDSTAT signal is switched to "1" in order to turn on the pass gates M4[15:0], and the RD and RDCMP signals are switched to "0" in order to turn off the pass gates M2[15:0], M3[15:0]. During an array read operation in the I/O compression test mode, the RDCMP signal is switched to "1" in order to turn on the pass gates M3[15:0], and the RD and RDSTAT signals are switched to "0" in order to turn off the pass gates M2[15:0], M4[15:0]. Furthermore, the CMP signal is switched to "1" in order to enable the pattern recognition block 40.
The pass gates M3[15:0] connect the output CMPOUT[15:0] through inverters I4[15:0] to the output drivers, which is split into 3 components 42 [3:0], 44[7:4], 46[15:8]. Inverters I5[15:0], I3[15:0] are weak inverters for ensuring that the inputs of inverters I4[15:0], I2[15:0], respectively, are at CMOS levels. The purpose of having 3 separate output driver components 42 [3:0], 44[7:4], 46[15:8] is to have more than one output driver enable signal, such as for example, the enable signals OE, OECMP, OEH for the drivers 42[3:0], 44[7:4], 46[15:8], respectively. Alternatively, the enable signals OE and OEH may be set equal to each other so that there are only two separate enable signals. During the I/O compression test mode, the enable signal OECMP is "1" to enable the output driver 44[7:4] so that the 4 data pins DQ[7:4] are active, and the enable signals OE and OEH are "0" to keep the output drivers for DQ[15:8] and DQ[3:0] deselected, or tri-stated.
Referring to FIG. 5, the pattern recognition block 40 includes detection blocks 48, 50, output logic 52, and inverters I8[15:0]. Four patterns are detected by the pattern recognition block 40: (1) all "0"; (2) all "1"; (3) checker board "010101010101010101"; and (4) inverted checker board "1010101010101010". Although only these four patterns are detected, it should be well understood that other patterns could be detected as well.
The purpose of the detection blocks 48, 50 is to detect patterns among the data bits sendat[15:0], i.e., detect patterns in which the data bits sendat[15:0] are arranged. Specifically, the purpose of the detection block 48 is to detect when the data lines sendat[15:0] are either all "0" or all "1". When either all "0" or all "1" is detected, the MATCH output goes to "1"; otherwise, the MATCH output remains at "0". The purpose of the detection block 50 is to detect when the data lines sendat[15:0] are in either the checkerboard or inverted checkerboard pattern. When either the checkerboard or inverted checkerboard pattern is detected, the CHBD output goes to "1"; otherwise, the CHBD output remains at Each of the detection blocks 48, 50 includes CMP and BYTE inputs. A "1" on the CMP inputs turns on the detection blocks 48, 50. The purpose of the BYTE inputs is to select that the detection be done in either byte mode (BYTE="1") or word mode (BYTE="0"). By using word mode the reading of the data will be done in one-half the time it takes to do it in byte mode.
The circuitry inside the detection blocks 48, 50 is the same. What differs between the two blocks 48, 50 are the inputs that are used. Specifically, the match detection block 48 receives sendat[15:0], and the checkerboard detection block 50 receives, in alternating order, sendat[0, 2, 4, 6, 8, 10, 12, 14] and sendat -- [1, 3, 5, 7, 9, 11, 13, 15]. The basic function of the circuitry inside both of the detection blocks 48, 50 is to detect all "0" or all "1" patterns. By inverting every other bit of sendat[15:0], i.e., applying sendat -- [1, 3, 5, 7, 9, 11, 13, 15], the checkerboard detection block 50 is able to detect the checkerboard or inverted checkerboard pattern in sendat[15:0].
The function of the detection blocks 48, 50 is best illustrated by the logic circuitry shown in FIGS. 6 and 7. In FIG. 6, word mode is selected when BYTE is "0" because this allows the output of AND2 to pass through OR1 and go to AND3, and the output of AND5 to pass through OR2 and go to AND6. Byte mode is selected when BYTE is "1" because this causes a "1" to be sent to one input of AND3 and a "1" to be sent to one input of AND6; therefore, the outputs of AND3 and AND6 are determined only by the outputs of AND1 and AND4, respectively. In other words, when BYTE is "1", AND2 and AND5 are bypassed.
AND1 detects when sendat[7:0]="11111111", and AND2 detects when sendat[15:8]="11111111". Therefore, the output of AND3 will be "1" in the following cases: 1) sendat[7:0]="11111111" and BYTE="1"; or 2) sendat[15:0]="1111111111111111" and BYTE="0". Specifically, assuming that word mode has been selected, the outputs of AND1 and AND2 will be "1" only if CMP is "1" and sendat[15:0] are all "1". When this occurs, the output of AND3 is "1" which causes MATCH to be "1". Similarly, when CMP is "1", AND4, AND5, AND6 and OR2 detect when sendat[7:0]="00000000" in byte mode and when sendat[15:0]="0000000000000000" in word mode. Specifically, assuming that word mode has been selected, the outputs of AND4 and AND5 will be "1" only if CMP is "1" and sendat -- [15:0] are all "1", which means that sendat[15:0] are all "0". When this occurs, the output of AND6 is "1" which causes MATCH to be "1". Thus, when MATCH="1", i.e., OR3 output="1", the sense amplifiers 34 (See FIG. 4) are reading all "1" or all "0" patterns.
In FIG. 7, word and byte modes are selected in the same manner as in FIG. 6. The output of OR6 will be "1" in the following cases: 1) BYTE="1" and sendat[7:0]="10101010"; 2) BYTE="0" and sendat[15:0]="1010101010101010". Specifically, assuming that word mode has been selected, the outputs of AND7 and AND8 will be "1" only if CMP is "1", sendat[0, 2, 4, 6, 8, 10, 12, 14] are all "1", and sendat[1, 3, 5, 7, 9, 11, 13, 15] are all "0". When this occurs, the inverted checkerboard pattern has been detected and the output of AND9 is "1" which causes CHBD to be "1". The output of OR6 will also be "1" in the following cases: 1) BYTE="1" and sendat[7:0]="0101010101"; and 2) BYTE="0" and sendat[15:0]="0101010101010101". Specifically, assuming that word mode has been selected, the outputs of AND10 and AND11 will be "1" only if CMP is "1", sendat[0, 2, 4, 6, 8, 10, 12, 14] are all "0", and sendat[1, 3, 5, 7, 9, 11, 13, 15] are all "1". When this occurs, the checkerboard pattern has been detected and the output of AND12 is "1" which causes CHBD to be "1". Thus, when CHBD="1", i.e., OR6="1", the sense amplifiers 34 (See FIG. 4) are reading either the checker board or inverted checker board pattern.
Although the logic circuitry shown in FIGS. 6 and 7 plainly illustrates the function of the detection blocks 48, 50, the circuitry 54 shown in FIG. 8 is a more practical circuit implementation of the detection blocks 48, 50. Specifically, the OUTPUT signal in the circuit 54 corresponds to either the MATCH or CHBD signals, depending upon whether the circuit 54 is being discussed in terms of the match detection block 48 or the checkerboard detection block 50, respectively. It should be noted that the circuit 54 will be the same for both the detection blocks 48, 50, but that the specific connections made to IN[15:0] will differ for each detection block 48, 50. Specifically, sendat[15:0] will be connected to IN[15:0] for the detection block 48, 50 in the manner shown in FIG. 5.
Whether the circuit 54 is used in the detection block 48 or 50, the basic function of the circuit 54 is the same. Specifically, if the enable signal CMP is "1" so that the circuit 54 is enabled, the OUTPUT signal will be "1" if the inputs IN[15:0] are either all "0" or all "1". If the inputs IN[15:0] are not all "0" or all "1", however, the OUTPUT signal will be "0". Furthermore, the circuit 54 also includes the BYTE -- input on many of the transistors. The BYTE -- signal is generated from the BYTE signal via inverter 60. When BYTE -- is "0", the circuit 54 is in byte mode and only inputs IN[7:0] are active; when BYTE -- is "1", the circuit 54 is in word mode and all inputs IN[15:0] are active.
The detailed operation of the circuit 54 is as follows. When CMP is "0", transistor M52 turns on due to inverter 58 and pulls OUTPUT down so that the circuit 54 is disabled. When CMP is "1", the weak pull up transistor M53 pulls OUTPUT up and the circuit is enabled. Because transistor M53 is only a weak pull up device, OUTPUT will be pulled down if a combination of any of the other transistors in the circuit 54 turn on so as to complete a path from OUTPUT to ground. Such a path to ground will be completed if the inputs IN[15:0] are not all "0" or all "1". (assuming BYTE="0"). As long as all of the inputs IN[15:0] are all "0" or all "1", OUTPUT will remain "1". It should be noted that the inputs IN[15:0] are used as the inputs of many of the transistors in the circuit 54, and the inputs IN -- [15:0] are also used as the inputs of many of the transistors in the circuit 54. An inverter 56[15:0] is used to provide the inputs IN -- [15:0].
The operation of the circuit 54 will be illustrated by way of the following examples. First assume that CMP is "1" so that the circuit is enabled and that BYTE -- is "0" so that the circuit 54 is in byte mode. With BYTE -- being "0", transistors M21, M23, M25, M27, M45, M47, M49, M51 will not be able to pull OUTPUT down, and thus, the inputs IN[15:8] will have no effect on the operation of the circuit. If IN[7:0]="00000000", none of the transistors M28, M30, M32, M34, M37, M39, M41, M43 will pull OUTPUT down. For example, although transistor M37 will be turned on, transistor M36 will be turned off, preventing OUTPUT from being pulled down. Likewise, although transistor M33 will be turned on, transistor M32 will be turned off, preventing OUTPUT from being pulled down. Similarly, if IN[7:0]="11111111", the result is the same. For example, although transistor M28 will be turned on, transistor M29 will be turned off, preventing OUTPUT from being pulled down. Likewise, although transistor M40 will be turned on, transistor M41 will be turned off, preventing OUTPUT from being pulled down. In both of these scenarios OUTPUT will remain "1" by being pulled up by transistor M53, indicating that IN[7:0] is either all "0" or all "1".
Now assume that CMP is still "1", but that BYTE -- is now "1" so that the circuit 54 is in word mode. With BYTE -- being "1", transistors M21, M23, M25, M27, M45, M47, M49, M51 will be able to pull OUTPUT down, and thus, all of the inputs IN[15:0] will have an effect on the operation of the circuit. If IN[15:0]="100000000000000", OUTPUT will be pulled down and will be "0". This is because transistors M35, M26, M27 are all turned on, completing a path between OUTPUT and ground. Similarly, If IN[15:0]="1111111110111111", OUTPUT will be pulled down and will be "0" because transistors M40, M41 will both be turned on. In both of these scenarios OUTPUT will be "0" indicating that IN[15:0] is not all "0" or all "1".
Referring again to FIG. 5, the purpose of the output logic 52 is to generate a number of output data bits, which is less than 16 data bits, which are arranged in a pattern which is indicative of the pattern in which the data bits of sendat[15:0] are arranged. Specifically, the output logic 52 generates the outputs CMPOUT[15:0] of the pattern recognition block 40. The outputs CMPOUT[15:8, 3:0] are generated by the inverter I9[15:8, 3:0] as follows: CMPOUT[15:8]=sendat -- [15:8] and CMPOUT[3:0]=sendat -- [3:0]. These two groups of bits are "do not care" in the I/O compression test mode. Specifically, as discussed above, in the I/O compression test mode the pattern recognition block 40 compresses the information in the 16 bits of sendat[15:0] down to the 4 bits CMPOUT[7:4]. Thus, the other bits in CMPOUT are not needed.
The outputs CMPOUT[7:4] are generated as follows. As a result of inverter I9[7, 4], CMPOUT[7]=sendat -- [7] and CMPOUT[4]=sendat -- [4] all of the time. The outputs CMPOUT[6:5], however, are determined by the states of the MATCH and CHBD signals. Specifically, when MATCH="0" and CHBD="0", this indicates that the pattern in sendat[15:0] is not all "0", all "1", checker board or inverted checker board. In this scenario, transistor M5 will be turned off and transistor M6 will be turned on. This will cause sendat -- [4] to be present at the input of inverter I12, and so CMPOUT[5]=sendat[4]. Furthermore, transistor M8 will be turned off and transistor M7 will be turned on. This will cause sendat -- [4] to be present at the input of inverter I14, and so CMPOUT[6]=sendat[4].
When MATCH="1" and CHBD="0", this indicates that the pattern in sendat[15:0] is either all "0" or all "1". In this scenario, transistor M5 will be turned on and transistor M6 will be turned off. This will cause sendat[4] to be present at the input of inverter I12, and so CMPOUT[5]=sendat -- [4]. Furthermore, transistor M8 will be turned off and transistor M7 will be turned on. This will cause sendat[4] to be present at the input of inverter I14, and so CMPOUT[6]=sendat -- [4].
When MATCH="0" and CHBD="1", this indicates that the pattern in sendat[15:0] is either checker board or inverted checker board. In this scenario, transistor M5 will be turned off and transistor M6 will be turned on. This will cause sendat -- [4] to be present at the input of inverter I12, and so CMPOUT[5]=sendat[4]. Furthermore, transistor M8 will be turned on and transistor M7 will be turned off. This will cause sendat[4] to be present at the input of inverter I14, and so CMPOUT[6]=sendat -- [4].
Finally, the scenario where MATCH="1" and CHBD="1" should never occur because it is impossible for the pattern in sendat[15:0] to simultaneously be either all "0" or all "1" and either checker board or inverted checker board.
As discussed above with respect to FIG. 4, during an array read operation in the I/O compression test mode, the RDCMP signal is switched to "1" in order to turn on the pass gates M3[15:0], and the RD and RDSTAT signals are switched to "0" in order to turn off the pass gates M2[15:0], M4[15:0]. The pass gates M3[15:0] connect the output CMPOUT[15:0] to the output drivers 42[3:0], 44[7:4], 46[15:8]. During the I/O compression test mode, the enable signal OECMP is "1" and the enable signals OE and OEH are "0" so that the output driver 44[7:4] corresponding to data pins DQ[7:4] is active and the output drivers 46[15:8], 42[3:0] corresponding to data pins DQ[15:8], DQ[3:0], respectively, are tri-stated. Due to the inverter I4[7:4], the outputs DQ[7:4]=CMPOUT -- [7:4].
Table 1 shows all of the possible values of the outputs DQ[7:4] in the I/O compression test mode and the corresponding values of CMPOUT[7:4], sendat[7:4], CHBD and MATCH. As shown in the last four lines of Table 1, DQ[7:4]="0101" when sendat[15:0] is in the checker board pattern, DQ[7:4]="1010" when sendat[15:0] is in the inverted checker board pattern, DQ[7:4]="0000" when sendat[15:0] is all "0", and DQ[7:4]="1111" when sendat[15:0] is all "1". DQ[7:4] will be different from these four patterns in all other cases.
TABLE 1______________________________________MATCH CHBD sendat <7:4> CMPOUT <7:4> DQ <7:4>______________________________________0 0 0000 1001 0100 0 0 0001 1110 0001 0 0 0010 1001 0110 0 0 0011 1110 0001 0 0 0100 1001 0110 0 0 0101 1110 0001 0 0 0110 1001 0110 0 0 0111 1110 0001 0 0 1000 0001 1110 0 0 1001 0110 1001 0 0 1010 0001 1110 0 0 1011 0110 1001 0 0 1100 0001 1110 0 0 1101 0110 1001 0 0 1110 0001 1110 0 0 1111 0110 1001 0 1 0101 1010** 0101 0 1 1010 0101** 1010 1 0 0000 1111** 0000 1 0 1111 0000** 1111______________________________________
A review of Table 1 illustrates why the outputs CMPOUT[6.5] are generated in the manner shown in FIG. 5 rather than just setting CMPOUT[6:5]=sendat -- [6:5]. Specifically, if all 4 output bits CMPOUT[7:4] were simply set equal to sendat -- [7:4], this would sometimes lead to incorrect results. For example, in line 1 of Table 1, sendat[7:4]="0000" which, if it were used as the output CMPOUT[7:4], would imply that sendat[15:0] is all "0". However, it is clear in line 1 of Table 1 that sendat[15:0] is not all "0" because the MATCH signal is "0". Because MATCH="0", the bits in sendat[15:0] are not all "0" or all "1". Another example is seen in line 6 of Table 1 in which sendat[7:4]="0101". If this were used as the output CMPOUT[7:4], it would imply that sendat[15:0] is in the checkerboard pattern. However, it is clear in line 6 of Table 1 that sendat[15:0] is not in the checkerboard pattern because the CHBD signal is "0". Because CHBD="0", the bits in sendat[15:0] are not in the checkerboard or inverted checkerboard pattern. Similar examples are seen in lines 11 and 16 of Table 1.
As mentioned above, the pattern recognition block 40 is enabled only during an I/O compression test mode. Specifically, many integrated circuits have certain test modes of operation in which the pins take on functions tailored specifically for testing purposes. Test mode enable circuitry inside these integrated circuits generates the signals which enable the circuitry which implements each specific test mode. Such test mode enable circuitry inside the memory chips 24, 26, 28, 30 is the circuitry which will generate the appropriate states of the CMP, RDCMP and RD signals during the I/O compression test mode.
By using the teachings of the present invention, the tester 22 is able to read the memory chips 24, 26, 28, 30 in the normal read mode and no data processing is needed to verify pass or fail conditions.
It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that structures and methods within the scope of these claims and their equivalents be covered thereby.
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A memory system operable in a normal mode of operation and a test mode of operation includes sensing circuitry which generates x number of data bits during a read cycle. A read path circuit, coupled to the sensing circuitry, transfers the x number of data bits generated by the sensing circuitry during a first read cycle in the normal mode of operation to x number of output nodes. A first detection circuit, coupled to the read path circuit, detects whether or not the x number of data bits generated by the sensing circuitry during a second read cycle in the test mode of operation are arranged in a pattern in which all bits are identical. A second detection circuit, coupled to the read path circuit, detects whether or not the x number of data bits generated by the sensing circuitry during the second read cycle in the test mode of operation are arranged in a pattern in which each two adjacent bits are different. An output circuit, coupled to the first and second detection circuits, generates y number of output data bits which are arranged in a pattern indicative of whether the x number of data bits generated by the sensing circuitry during the second read cycle in the test mode of operation are identical, are arranged in a pattern in which each two adjacent bits are different, or are arranged in another pattern, and wherein y is less than x. A method of testing an integrated circuit (IC) memory is also disclosed.
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BACKGROUND OF THE INVENTION
The invention relates to a method and a device for detecting the presence or absence of one or more of a fixed number of certain frequencies within a pulse code modulated (PCM) signal, the signal to be investigated being multiplied by each of two reference series for each of the said certain frequencies.
A method and device of this kind are known from Proudfoot U.S. Pat. No. 3882283 issued May 6, 1975.
The method and device are applied in telecommunication exchanges in detecting voice-frequency signalling signals, such as different frequencies corresponding to digits on pushbuttons or on a dial of a telephone set contained in a telecommunication channel itself or in a separate signalling channel.
As detection devices for signalling purposes are widely used in telecommunication exchanges, it is clearly desirable that each detection device is used as efficiently as possible, so that space can be saved in the construction of the exchange and an economically more attractice solution is found. On the other hand, the standards to be met by the detection devices have been laid down in CCITT-recommendations Q440-Q458, which show that detection has to take place within a rather short time even if the frequencies received are somewhat different from the ones expected.
Although the device described in the above-mentioned patent is reasonably insensitive to inaccuracies in the frequency of the signals received, the components of the device are not used very efficiently. An improvement has been realized with the method and device described in applicants' asignees Drukarch U.S. Pat. No. 4068309 issued Jan. 10, 1978, but the latter has the drawback of being sensitive to frequency deviations and level variations of the signal. Both devices have the disadvantage that they cannot properly handle the occurring sum and difference frequencies.
The object of the invention is to provide a method and device which, starting from those described in the Proudfoot U.S. Pat. No. 3882283, yield a more efficient use of the equipment and more reliable detection.
SUMMARY OF THE INVENTION
The invention is based on the insight that twice as many samples of the signal to be detected are available as are needed for reliable detection according to the sampling theorem, so that half of the samples can remain unused.
However, in practice it proves to be impossible to use and not use successive samples alternately. Further, if the detection time is too short or too long this may lead to the introduction of too many sum and difference frequencies.
The method according to the invention is characterized in that sets of two subsequent ones of the samples available for detection within a PCM signal are alternately used and not used for detection. An improvement of the said method consists in that the number of samples used for detection is equal or practically equal to half a whole multiple of the number of samples which, at the sampling frequency, represent one period of the difference frequency of the said certain frequencies.
Furthermore, the invention provides a device for carrying out the first-mentioned method, which device comprises the means of comparing alternately two samples of a first PCM-signal and two samples of a second PCM-signal with the samples of the reference series, and means for feeding the results of this comparison alternately in the same rhythm to the detection device. As one relatively expensive and large detection device can be used for the signals of two channels instead of two detection devices, i.e. one detection device for each channel, an attractive solution is realized.
BRIEF DESCRIPTION OF THE VIEWS
The above mentioned and other features, objects and advantages, and the manner of attaining them are described more specifically below by reference to embodiments of this invention shown in the accompanying drawings, wherein:
FIG. 1 a general schematic block wiring diagram of a device according to the invention for alternate processing of the signals from two different PCM-channels;
FIG. 2 a schematic block wiring diagram of one of the discriminator circuits 6 shown in FIG. 1;
FIG. 3 a schematic block wiring diagram of a device according to the invention for time division processing of the signalling information from sixteen channels similar to the system disclosed in FIG. 1 for two channels;
FIG. 4 a waveform time-diagram showing the situation in time of the time slots (FS) containing the signalling information and the switching frequency (AS) according to the invention;
FIG. 5 a flowchart for the functional description of input control circuit 28 of FIG. 3;
FIG. 6 a flowchart for the functional description of input processing circuit 27 of FIG. 3;
FIG. 7 a flowchart for the functional description of output control circuit 41 of FIG. 3, and
FIG. 8 a flowchart for the functional description of output processing circuit 40 of FIG. 3.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The block diagram of FIG. 1 comprises an input memory 1 for the incoming series of signals of a first PCM-signal channel A and an input memory 2 for an incoming series of signals of a second PCM-signal channel B.
A switch 3 provides for throughconnection of the series of signals. According to the invention, a square-wave oscillator 4 controls switch 3 in such a way that two samples from each of the input memories 1 and 2 are alternately connected to the detector circuit of this invention. Square-wave oscillator 4 is synchronized with the incoming signal in the known manner (not shown). The signal coming from switch 3 is fed via a common input 5 to each of discriminators 6, each of the latter being suitable for the discrimination of one frequency. The construction and operation of a discriminator 6 is described later with the aid of FIG. 2. Each discriminator 6 is equipped with an input 7 for reception of the square-wave signal of oscillator 4. Further, the discriminators 6 each have an output 8, at which alternately appears an accumulated value of a comparison of a sine sample of signals A and B, respectively, and an output 9 at which appears a similar value of the comparison with a cosine sample of signals A and B. Outputs 8 and 9 are connected to a known comparator circuit 10. The outputs of comparator circuit 10 are conducted to switches 11, which according to the invention are controlled by oscillator 4. On each of the six outputs 12 a signal may now appear which is representative of each of the frequencies found in signal A, respectively. If for instance of two-out-of-six signalling code is applied, only two of the outputs 12 will be simultaneously "high" for example and the other four "low". On outputs 13 an identical situation is found for the frequencies encountered within signal B.
FIG. 2 presents a more detailed diagram of one of the discriminators 6 of FIG. 1. Each of these discriminators 6 is suitable for one of the six frequencies. The signal from input 5 is fed to a known detection device 14, which signal is multiplied by a sine reference series of the frequency concerned stored in a buffer 15, and in a buffer 16 by a cosine reference series of the frequency concerned. The result of both multiplications is fed via two switches 17 to two of four accumulators 18, 19, 20 and 21. The results of the multiplication of signal A by the sine reference series are stored in accumulator 18; those for signal B in accumulator 19. The results of the multiplication of the signals from PCM-signals A and B with the cosine reference series are accumulated in accumulators 20 and 21, respectively.
Via two switches 22, which according to the invention are controlled by square-wave oscillator 4 (FIG. 1), the accumulation products are fed to outputs 8 and 9.
Where the function and operation of the components mentioned are either generally known or are described, in particular, in the Proudfoot U.S. Pat. No. 3,882,283, they will not be further discussed here.
A considerable saving is achieved by the fact that the most complicated parts of the circuit, such as detection device 14 (FIG. 2) and comparator circuit 10 (see FIG. 1) are used twice as efficiently as in the known circuits, without the processing speed being increased. As stated above, this is realized according to the invention by alternately using and not using two samples of each of signals A and B. Theoretically it is possible to make another choice, for instance the alternate use and non-use of a single sample. However, if the frequencies received vary by approx. 10 Hz, as is allowed according to CCITT recommendation Q455, so many modulation products prove to occur in practice, that reliable detection within the time mentioned in the recommendation is no longer possible. Practical tests have shown that the alternate use and non-use of two samples with the most extreme ones of the values mentioned in the recommendation in question, even increases the reliability of the detection.
Also with lower frequency algorithms, such as alternately using and not using three samples, it is found that one or more of the frequencies used cannot be reliably detected any more.
FIG. 3 shows a preferred embodiment of a device according to the invention for detecting MFC (multi-frequency code) signalling signals in each of the eight channels of two frames.
In accordance with international agreements, PCM-samples for signalling are offered in a 125 μs frame comprising 32 time slots (see FIG. 4). The incoming PCM-samples with MFC signalling are distributed in the exchange over time slots TO, T4, T8, T12, T16, T20, T24 and T28. So there are 8 MFC signalling channels with a channel spacing of 15.6 μs.
The detection device is controlled by the central processing unit of the telephone exchange (not shown). The operation of this central processing unit is of no importance in explaining the invention and can therefore be left out of consideration. An MFC detection device for both the outgoing and the incoming direction will comprise 12×2 reference series and 6×2 accumulators. By designing the detection device in such a way that detection of a sample from a time slot is completed within 15.6 μs, the detection device can, according to the invention, in the intervening time be used for processing the MFC-signals from another frame.
FIG. 3 shows such a device in which a multi-channel PCM-signal A is received on an input 23 and a multi-channel PCM-signal B on an input 24, of which PCM-signals each time the parts containing the MFC-signals are fed to input bus 26 by the input selector 25. Input selector 25 operates under the control of a synchronization signal FS (see FIG. 4), which becomes "high" during each time the eight time slots T0-T28 , and of a synchronization signal AS, which according to the invention changes its sign every two frames f and as a result alternately feeds two of each of the time slots with signalling information from PCM-signal A, and then two of each of the time slots with signalling information from PCM-signal B to input bus 26.
The synchronization characters FS and AS are direct derivatives of the signal received by the telephone exchange. The formation of these signals is generally known and will not be discussed here.
The signal from input bus 26 (see FIG. 3) is fed to an input processing circuit 27. Circuit 27 processes each incoming signal in the same way without distinguishing between channels. FIG. 6 is a flowchart of circuit 27, corresponding to the discriminator circuits 6 shown in FIG. 2, which consists of part of a microprocessor circuit.
Input control circuit 28 is realized together with circuit 27 by means of a microprocessor; the two circuits have been drawn separately in order to emphasize the two different functions. Circuit 28 sees to it that at the right moment the right data is released to enable circuit 27 to carry out an operation according to the flow chart of FIG. 5. Circuit 28 is linked to the frame by means of synchronization signals FS and AS (FIG. 4).
The reference series are stored in a programmable read-only memory (PROM), reference series buffer 29. As stated above, it contains 12 sine reference series and 12 cosine reference series.
Further, the circuit comprises an accumulator 30 for frame of signals A, in which the data are accumulated in the known manner after having been processed by circuit 27. Accumulator 30 has been embodied as a random access memory (RAM). It contains the accumulated data for eight PCM time slots, notably T0, T4, T8, T12, T16, T20, T24 and T28 (see FIG. 4). For each of these eight channels, accumulator 30 comprises 14 lines, so that the total capacity of the accumulator is at least 8×14=112 lines. An RAM of 16×128 bits is applied in the circuit. The fourteen lines are used for the accumulated values of the sine and cosine of each of the six frequencies that may occur in a signal, and the last two lines are used for a status word. The status word comprises, among other things, the address of the detection device, the number of samples processed and the condition of the detection device.
Likewise, an accumulator 33, identical to accumulator 30, has been provided for the accumulated data of the frame of signals B, with an address selector 34 and a data selector 35.
For the exchange of signals, an input address bus 36 has been provided via which input control circuit 28 can feed address information to buffer 29 and address selectors 31 and 34. Via input control bus 37, circuits 27 and 28 can give orders to each other and to buffer 29 and selectors 32 and 35. The data to be processed are exchanged via a bidirectional input data bus 38.
The circuit in FIG. 3 also incorporates an output processing circuit 40 for processing the data stored in the accumulators 30 and 33, and an output control circuit 41. Output circuits 40 and 41 have been jointly embodied as one micropressor and have been drawn separately because of their different functions. The functional operation of output circuits 40 and 41 is illustrated by FIGS. 8 and 7, respectively. The data processed by output circuit 40 can be fed to the central processing unit of the telephone exchange via output buses. In the same way as in the input section. These output connections are provided by means of an output address bus 46, an output control bus 47 and a bidirectional output data bus 48.
Input control circuit 28 and output control circuit 41 can both effect changes in each of the status words associated with each of the eight time slots. This presents the possibility of an exchange of messages between circuits 28 and 41. The operation of the circuit according to FIG. 3 will be illustrated by means of FIGS. 4, 5, 6, 7 and 8. The microprocessors incorporated in the circuit, namely the combination of input circuits 27 and 28 and that of output circuits 40 and 41, will not be further explained. For insiders these circuits have been sufficiently described by the flowcharts of FIGS. 5, 6, 7 and 8.
Input control circuit 28 waits for signal AS to change its sign. As appears from FIG. 3, this causes accumulator 30 to become accessible when signal AS is "high", or causes accumulator 33 to become accessible when signal AS is "low". After the change of signal AS, circuit 28 waits till signal FS also becomes "high", after which it is investigated whether the status word associated with time slot T0 contains a detection order. If there is an order in time slot T0, the input control circuit 28 determines the starting address of the character bits in the reference series buffer 29 and the starting address in selector 31 or 34, respectively of the accumulated values for time slot T0 in accumulator 30 or 33, depending on signal AS. Thus input control circuit 28 now regularly places an address on address bus 36 and orders the input processing circuit 27 via control bus 37 to collect the data from the accumulator in input control circuit 27 and to add them to the result of the multiplication of the samples from input selector 25 and reference series buffer 29, respectively, and to place the final result in the accumulator 30 or 33. This process is repeated for each of the six frequencies that may be found in each time slot FS (see FIGS. 4 and 6).
This same process is applied to the signals in time slots T4, T8, T12, T16, T20, T24 and T28.
As FIG. 4 shows, two frames f of one PCM-channel are processed in succession each time, and then two frames f of a second PCM-channel. The results of the first PCM-channel are stored in accumulator 30 each time via data selector 32, and the results of the second PCM-channel are fed to accumulator 33 via data selector 35.
According to the invention the number of samples of each time slot required equals half a multiple of the number of samples by means of which a 120 Hz period (the fixed difference frequency between the MFC frequencies) can be defined.
At a given sampling frequency of 8 kHz, a 120 Hz period is defined by sixty-seven samples. Two periods are defined by one hundred thirty-four samples and three periods by two hundred samples. By choosing each time a multiple of sixty-seven samples, the samples of the positive and negative parts of the sine and cosine of 120 Hz cancel each other out when multiplied.
In the device described here two hundred samples have been chosen, so that after cancellation of half of this number, a detection is complete after one hundred samples. Each time when 50×2 frames have been processed and accumulated, input control circuit 28 changes the status word stored in accumulators 30 and 33 and discontinues the processing of the signals received.
When the central processing unit (not included in the Figures) has given a detection order via input 43 (FIGS. 3 and 7) and output control circuit 41 concludes from the status word in the accumulator 30 or 33 concerned that the detection procedure is completed, the results of the accumulation are fed to the working store of the input processing circuit 40 under the control of the output control circuit 41. According to flowchart of FIG. 8 these data are now processed. The moduli of the values of the cosine accumulator and those of the sine accumulator of one frequency are compared with each other. Subsequently, the smaller of the two values is multiplied by a factor 1/8, 1/4 or 3/8. The multiplication factor depends on the ratio between the largest and the smallest accumulator value. The largest value and the smallest value multiplied by the factor are now added together in this output processing circuit 40. A similar operation is carried out on the values of the sine and cosine accumulators of the other frequencies. After that, the frequency combination of the values of the two largest processing results is determined and passed on to output control circuit 41.
If the detection has been unsuccessful, a new detection order is given; if the detection has been successful, the result is stored in output buffer 44, where it can be collected by the central processing unit (not included in the Figures).
With the device described in the aforegoing it proves to be possible to detect an MFC-signal within 25 ms, detection taking place in a total of 17 MFC-channels from two different PCM-channels as a result of the application of time division. This is subject to the condition that the eight MFC-channels are regularly distributed over the frame. This need not be a drawback because, in a telephone exchange operating on a time division basis, the incoming signalling signals can be distributed regularly in time via the first time interval of the exchange.
While there is described above the principles of this invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of this invention.
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According to the method of the invention two successive samples from each of two signal channels to be detected are alternately fed and not fed to the detection device. In consequence of this, fewer interference products are obtained, so that the processing time can remain relatively short. Moreover the two multi-frequency code samples (MFC-samples) of two channels can be processed simultaneously. A device (FIG. 3) examines on a time division basis the signalling time slots of two pulse code modulated frames of multi-channel signals (PCM-frames). Under the control of a microprocessor circuit (27) the pulse code modulated selected multi -frequency signal samples are processed in an input control circuit (28) when they are correlated with one another by being multiplied by sine and cosine reference series signals from a buffer (29). The correlation results are fed to accumulators (30, 33). Under the control of a second microprocessor circuit (40) the correlation results are compared in a processing circuit and transferred to the equipment that follows.
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This application is a continuation, of application Ser. No. 08/099,930 filed Aug. 3, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for dyeing cloths by an ink let method, a printed article and an ink jet printing apparatus for use in the method.
2. Related Background Art
Nowadays, the main techniques of dyeing are screen textile printing and roller textile printing. However, these printing systems are not suitable for the production of many kinds of articles in small amounts, and the prompt application of these systems to fashion is also difficult. Thus, in recent years, it has been desired to develop an electronic textile printing system which does not require any plate making.
In answer to this demand, many dyeing methods using ink jet have been suggested, and they are largely expected in various fields.
Requirements of the ink jet dyeing are
(1) that a sufficient density is given to a developed color,
(2) that a color yield of a dye on a cloth is high, and after a washing step, the treatment of a waste solution is easy,
(3) that irregular bleeding due to the mixing of different colors on the cloth is not remarkable,
(4) that colors in wide range can be reproduced, and
(5) that stable productivity is always possible.
In order to meet these requirements, conventionally, various kinds of additives have been mainly added to an ink, the shot-in quantity of the ink has been adjusted, or the cloth has been beforehand treated. These techniques are insufficient to meet all of the above-mentioned requirements.
For example, when the inks are mixed or adjacently dyed on the cloth, the density and the color tone of printed colors and the reproducibility of the colors printed under the same dyeing conditions depend largely upon the combination or the shot-in order of dyes to be used. In consequence, the above-mentioned requirements (1), (3), (4), (5) and the like cannot be often met. For the sake of expressing the various colors, the above-mentioned conventional techniques are still poor.
Particularly, in the ink jet dyeing, it is desired to express more kinds of colors than in a conventional ink jet print onto a recording material such as a paper. With regard to an image of a black color, a black ink has been mixed with other colors so as to express a desired finely different black color, and in this case, the above-mentioned problems have often occurred.
Furthermore, also in a boundary between a black image and another color image, the above-mentioned problems are remarkable, so that any sharp and bleeding-free image cannot be formed.
SUMMARY OF THE INVENTION
Thus, an object of the present invention is to provide an ink jet printing method by which the above-mentioned problems of the ink jet dyeing at the time of the ink jet dyeing can be solved, and especially in the case that an image is formed by printing a black color adjacently to another color or by mixing these colors, good color developing properties and the sharp and bleeding-free image can be obtained stably, even when the shot-in order of dyes and dyeing conditions are changed.
Another object of the present invention is to provide a printed article by the use of the above-mentioned ink jet printing method.
Still another object of the present invention is to provide an ink jet printing apparatus for use in the above-mentioned ink jet printing method.
These objects can be achieved by the following techniques of the prevent invention.
The first aspect of the present invention is directed to an ink jet printing method for printing inks of at least two colors on a cloth by an ink jet system which comprises at least three steps of:
(a) the step of printing, on the cloth, the inks of at least two colors of a black ink and an another ink of at least one color selected from the group consisting of yellow, orange, red, magenta, blue and cyan so that the inks may at least partially overlap,
(b) the step of thermally treating the cloth printed with the inks, and
(c) the step of washing the thermally treated cloth,
said cloth comprising a polyamide fiber,
said black ink containing, as a dyestuff, at least one selected from the group consisting of
C. I. Acid Black 24, 26, 52, 52:1, 109, 155, 172 and 222,
C. I. Direct Black 19, 62 and 113, and a dyestuff represented by the formula (1) ##STR3## wherein M is an alkaline metal, ammonium or an amine, or the formula (2) ##STR4## wherein X is a hydrogen atom, a lower alkyl group or a phenyl group which may be substituted by an SO 3 M group; m is 0 or 1; M is an alkaline metal, ammonium or an amine; each of A, B and C is a benzene ring or a naphthalene ring which may have a substituent, but B and C are not simultaneously the naphthalene rings.
The second aspect of the present invention is directed to an article printed by the above-mentioned ink jet printing method.
The third aspect of the present invention is directed to an ink set for use in the above-mentioned ink jet printing method, said ink set being characterized by including at least two color inks of a black ink and an another ink of at least one color selected from the group consisting of yellow, orange, red, magenta, blue and cyan.
The fourth aspect of the present invention is directed to a printed article in which a cloth is printed in a partial overlap state with at least two dyestuffs of a black dyestuff and at least one dyestuff selected from the group consisting of yellow, orange, red, magenta, blue and cyan,
said black dyestuff containing at least one selected from the group consisting of
C. I. Acid Black 24, 26, 52, 52:1, 109, 155, 172 and 222,
C. I. Direct Black 19, 62 and 113, a dyestuff represented by the formula (1) ##STR5## wherein M is an alkaline metal, ammonium or an amine, or the formula (2) ##STR6## wherein X is a hydrogen atom, a lower alkyl group or a phenyl group which may be substituted by an SO 3 M group; m is 0 or 1; M is an alkaline metal, ammonium or an amine; each of A, B and C is a benzene ring or a naphthalene ring which may have a substituent, but B and C are not simultaneously the naphthalene rings, and
said printed article being a cloth comprising a polyamide fiber.
The fifth aspect of the present invention is directed to a processed article obtained by further processing the above-mentioned printed article.
The sixth aspect of the present invention is directed to a recording unit for use in the above-mentioned ink jet printing method which is equipped with an ink containing portion containing the ink and a head portion for ejecting the ink in the form of ink droplets.
The seventh aspect of the present invention is directed to an ink cartridge for use in the above-mentioned ink jet printing method which is equipped with an ink containing portion containing the ink.
The eighth aspect of the present invention is directed to an ink jet printer for use in the above-mentioned ink jet printing method which is equipped with a recording unit having an ink containing portion containing the ink and a head for ejecting the ink in the form of ink droplets.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross section of a head of an ink jet recording apparatus.
FIG. 2 is a cross section of the head portion of the ink jet recording apparatus.
FIG. 3 is a perspective view illustrating the appearance of a head obtained by multiplying the head shown in FIG. 1.
FIG. 4 is a perspective view illustrating one example of the ink jet recording apparatus.
FIG. 5 is a longitudinal cross section of an ink cartridge.
FIG. 6 is a perspective view of a recording unit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, the present invention will be described in detail.
A material constituting a cloth which can be used in the present invention include polyamide fibers. Above all, nylon, silk and wool are preferable. These fibers can be used in any form of fabric, knit and nonwoven fabric.
Needless to say, the cloth preferably comprises 100% of the polyamide fiber, but a mixed fabric, a mixed nonwoven fabric and the like of the polyamide fiber and another material such as rayon, cotton, acetate fiber, polyurethane fiber or acrylic fiber can also be used as the cloth for textile printing in the present invention, so long as a mixing ratio of the polyamide fiber is 30% or more, preferably 50% or more.
The physical properties of the polyamide fiber constituting the cloth and a thread comprising this fiber should be present in a certain range. For example, in the case of the nylon, the average thickness of the nylon fiber is preferably controlled to from 1 to 10 d (denier), more preferably from 2 to 6 d, and the average thickness of the nylon thread comprising the nylon fiber is preferably controlled to from 20 to 100 d, more preferably from 25 to 80 d, most preferably from 30 to 70 d.
In the case of the silk, as characteristics of the fiber itself, the average thickness of the silk fiber is preferably controlled to from 2.5 to 3.5 d, more preferably from 2.7 to 3.3 d, and the average thickness of the silk thread comprising the silk fiber is preferably controlled to from 14 to 147 d, more preferably from 14 to 105 d. The cloth of such a silk which is prepared by a known method can be preferably used.
The cloth which is used in the present invention can be subjected to a conventional pretreatment, if necessary. In particular, it is more preferable to pretreat the cloth with a solution containing from 0.01 to 20% by weight of urea, a water-soluble metallic salt or a water-soluble polymer.
Examples of the water-soluble polymer include starch of corn, wheat and the like, cellulosic substances such as carboxymethyl cellulose, methyl cellulose and hydroxyethyl cellulose, polysaccharides such as sodium alginate, gum arabic, locust bean gum, gum tragacanth, guar gum and tamarind seeds, proteins such as gelatin and casein, and known natural water-soluble polymers such as tannin and lignin. Examples of synthetic polymers include known polyvinyl alcohol compounds, polyethylene oxide compounds, acylic acid-based water-soluble polymers and maleic anhydride-based water-soluble polymers. Among these compounds, the polysaccharide polymers and the cellulosic polymers are preferable.
Examples of the water-soluble metallic salts include halides of alkaline metals and alkaline earth metals which can form typical ion crystals and which have a pH in the range of from 4 to 10. Typical examples of these halides of the alkaline metals include NaCl, Na 2 SO 4 , KCl and CH 3 COONa, and typical examples of these halides of the alkaline earth metals include CaCl 2 and MgCl 2 . Above all, the salts of Na, K and Ca are preferable.
Next, reference will be made to a dyestuff by which the present invention is characterized and which is contained in the ink of the present invention.
The dyestuffs which can be used in the ink of the present invention are classified into acid dyes and direct dyes, and they are extremely limited from the viewpoints of color tone, dyeing properties, ejection properties and the like.
The present inventors have found that in an ink jet dyeing technique for successively ejecting ink droplets on a cloth, the quality of a printed article depends largely upon fine differences of a combination of the dyes to be used, the shot-in order and dyeing conditions.
This phenomenon are particularly influential in forming an image by printing the black color adjacently to another color or by mixing these colors.
In view of the above-mentioned problems, the present inventors have intensively conducted investigations, and they have found that a stable and good printed article can be obtained without being affected by the fine differences of the shot-in order and the dyeing conditions.
Among these dyestuffs, a particular interrelation is required, and they are extremely similar to each other in dyeing properties, coloring properties, affinity to another dyes and fibers, and the like.
In consequence, the dyestuffs which can be used in the present invention are limited to the following substances:
As dyestuffs in a black ink, C. I. Acid Black 24, 52, 52:1, 172, C. I. Direct Black 113, a compound represented by the formulae (4) and (5) ##STR7## wherein S is an SO 3 Li group, As dyestuffs in a yellow ink, C. I. Acid Yellow 19, 49, 79, 141, 169, C. I. Direct Yellow 58, 86, 132,
As dyestuffs in an orange ink, C. I. Acid Orange 56, 95, 156, C. I. Direct Orange 34,
As dyestuffs in a red ink, C. I. Acid Red 35, 114, 127, 145, 266, 318, 337, 361, C. I. Direct Red 89, 212,
As dyestuffs in a magenta ink, C. I. Acid Red 143, 143:1, 249, 254, 265, 274, C. I. Acid Violet 47, 54, a compound represented by the formula (3) ##STR8## wherein Y is a hydrogen atom, a methyl group, a methoxy group, an acetylamino group or a nitro group, and it may form a naphthalene nucleus together with an adjacent benzene ring; X is an acetyl group, a benzoyl group, a paratoluenesulfonyl group or 4-chloro-6-hydroxy-1,3,5-triazine-2-yl group; and M is an alkaline metal, ammonium or an amine, and among them above, especially a compound represented by the formulae (6) and (7) ##STR9## As dyestuffs in a cyan ink, C. I. Acid Blue 185, C. I. Direct Blue 86, 87, 189, 199, and
As dyestuffs in a blue ink, C. I. Acid Blue 41, 62, 78, 80, 138, 140, 182, 205, 260, 277:1, 350.
At least one of these dyestuffs is contained in the ink. The total amount of the dyestuffs is usually in the range of from 1 to 20% by weight, preferably from 1.5 to 15% by weight, more preferably from 2 to 10% by weight based on the total weight of the ink.
The ink of the present invention contains at least the above-mentioned dyestuff and an aqueous medium.
The amount of water is usually in the range of from 10 to 93% by weight, preferably from 25 to 87% by weight, more preferably from 30 to 80% by weight.
In addition, as an aqueous medium, an organic solvent is preferably used together with water.
Examples of the organic solvent include ketones and ketoalcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; oxyethylene or oxypropylene addition polymers such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol and polypropylene glycol; alkylene glycols containing an alkylene group of 2 to 6 carbon atoms such as ethylene glycol, propylene glycol, trimethylene glycol, butylene glycol, and hexylene glycol; thiodiglycol; glycerin, 1,2,6-hexatriol; lower alkyl ethers of polyvalent alcohols such as ethylene glycol monomethyl (or monoethyl) ether, diethylene glycol monomethyl (or monoethyl) ether and triethylene glycol monomethyl (or monoethyl) ether; lower dialkyl ethers of polyvalent alcohols such as triethylene glycol dimethyl (or diethyl) ether and tetraethylene glycol dimethyl (or diethyl) ether; sulfolane, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone.
The above-mentioned media may be used singly or in combination, but the most preferable aqueous medium composition is a solvent containing at least one polyvalent alcohol. Above all, aqueous media containing thiodiglycol or diethylene glycol alone as well as both diethylene glycol and thiodiglycol in combination are particularly suitable.
The amount of the water-soluble organic solvent is usually in the range of from 5 to 60% by weight, preferably from 5 to 50% by weight based on the total weight of the ink.
As other substances to be added, there are chlorine ion and/or sulfate ion. When the chlorine ion and/or the sulfate ion are added in an amount of about 10 to about 20,000 ppm with respect to the dyestuff contained in the ink, coloring properties such as leveling properties and a color yield can be further improved preferably.
Furthermore, it is preferable that at least one selected from the group consisting of silicon, iron, nickel and zinc is contained in the ink, in a total amount in the range of from 0.1 to 30 ppm, preferably from 0.2 to 20 ppm, more preferably 0.3 to 10 ppm.
In addition, it is preferred that the ink contains calcium and/or magnesium together with the above-mentioned metal, the total amount of calcium and/or magnesium being in the range of from 0.1 to 30 ppm, preferably from 0.2 to 20 ppm, more preferably from 0.3 to 10 ppm. The addition of calcium and/or magnesium further improves the color yield.
The main components of the ink which can be used in the present invention are as described above, but other known additives can also be added, if necessary. Examples of the additives include a known dispersant, surface active agent, viscosity modifier, surface tension modifier and fluorescent brightener.
Examples of these additives include viscosity modifiers such as polyvinyl alcohols, celluloses and water-soluble resins; cationic and nonionic surface active agents; surface tension modifiers such as diethanolamine and triethanolamine; a pH adjustor such as a buffer solution; and a fungicide.
In the ink jet printing method of the present invention, a plurality of ink droplets are successively printed on the above-mentioned cloth, so that color mixing portions of at least two colors are formed. In this case, the total amount of the adhered dyestuffs in the color mixing portions is in the range of from 0.025 to 1 mg/cm 2 , preferably 0.04 to 0.7 mg/cm 2 , more preferably 0.05 to 0.5 mg/cm 2 . This value can be determined by measuring the amount of the ejected ink and the density of the dyestuff in the ink. If the amount of the adhered dyestuff is less than 0.025 mg/cm 2 , it is difficult to develop the colors at the high density, and therefore the effects of the present invention are not definitely exerted. If it is more than 1 mg/cm 2 , the noticeable improvement effects in density, color yield and the like cannot be recognized.
The ink jet system which can be used in the above-mentioned ink jet method of the present invention may be any of conventional and known ink jet recording systems, but for example, a system in which the ink is subjected to the function of thermal energy in accordance with a process described in Japanese Patent Application Laid-open No. 54-59936 to bring about a volume change and the ink is then ejected through a nozzle by the functional force of this condition change, i.e., a thermal let system is most effective. This reason can be considered to be that in the above-mentioned system, the election rate of the ink is mainly in the range of from 5 to 20 m/sec, and the scatter of the droplets at the time of the ejection is particularly suitable for the cloth containing a polyamide fiber. According to the present invention, even if recording is continuously carried out for a long period of time in accordance with the above-mentioned system, soils on its heater do not settle and disconnection does not occur, which permits the stable textile printing.
In addition, in carrying out the above-mentioned ink jet printing method regarding the present invention, as conditions for obtaining the particularly high effects, it is preferable that an ejection droplet is from 20 to 200 pl, an ink shot-in quantity is from 4 to 40 nl/mm 2 , a driving frequency is 1.5 kHz or more, and a head temperature is from 35° to 60° C.
Furthermore, the thus formed ink for the textile printing of the present invention is applied onto the above-mentioned cloth, but this application state is only an adhesive state. Therefore, it is preferable to successively carry out a fixing process for fixing the dyestuff on the fiber and a dyestuff removal process for removing the unfixed dyestuff. As the fixing process and the unfixed dyestuff-removing process, conventional and known methods are acceptable. For example, these processes can be achieved in accordance with the conventional and known technique for washing after a treatment by a steaming method, an HT steaming method or a thermofixing method. Among them, in case of adopting the HT steaming method, the effect of the present invention can be exhibited most effectively.
Moreover, the thus obtained printed article is cut into a desired size, if necessary, and the cut pieces of the cloth will be subjected to steps of sewing, adhesion, fusing and the like so as to obtain final articles such as neckties and handkerchieves.
One example of apparatus suitable to carry out the textile printing by the use of the ink of the present invention is an apparatus in which heat energy corresponding to a recording signal is applied to the ink in a chamber of a recording head to eject ink droplets. Now, this kind of apparatus will be described.
A constitutional example of the head which is the main portion of the apparatus is shown in FIGS. 1, 2 and 3.
A head 13 is obtained by combining a glass, ceramic or plastic plate having a groove 14 for allowing an ink to pass therethrough with a heating head 15 (the head is shown in the drawings, but the present invention is not limited thereto). The heating head 15 is constituted of a protective film 16 formed from silicon oxide and the like, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 formed with Nichrome or the like, a heat accumulating layer 19 and a base plate 20 made of a material having a good heat releasing property such as alumina.
An ink 21 reaches an election orifice (fine pore) 22 and forms a meniscus 23 by pressure P.
Now, when an electrical signal is applied to the electrodes 17-1 and 17-2, heat is abruptly generated from a region indicated by of the heating head 15 to generate bubbles in the ink 21 which comes in contact with the heating head 15. Then, the meniscus 23 is protruded by the resultant pressure to eject the ink 21, so that recording droplets 24 fly from the orifice 22 toward a cloth 25 containing a polyamide fiber. FIG. 3 shows an appearance of a multi-head in which many heads one of which is shown in FIG. 1 are arranged. The multi-head is formed by closely combining a glass plate 27 having a multi-groove 26 with the same heating head 28 as in FIG. 1. In this connection, FIG. 1 a sectional view of the head 13 along an ink flow channel, and FIGS. 2 is a sectional view cut along a line A-B in FIG. 1.
FIG. 4 shows one example of an ink jet recording apparatus incorporated with the head.
In FIG. 4, reference numeral 61 is a blade as a wiping member, and its one end is a fixed end which is supported by a blade supporting member and which functions as a cantilever. The blade 61 is disposed adjacent to a recording region for the recording head. In this embodiment, the blade 61 is held so as to protrude into a moving passage of the recording head. Reference numeral 62 is a cap which is disposed at a home position adjacent to the blade 61 and which can move in the moving direction of the recording head and a vertical direction in order to come in contact with an ejection hole surface and cap the same. Furthermore, reference numeral 63 is an ink absorber arranged adjacent to the blade 61 and held so as to protrude into the moving passage of the recording head. An ejection recovery portion 64 is constituted of the blade 61, the cap 62 and the absorber 63, and water and dust on the ink ejection hole surface are removed therefrom by the blade 61 and the absorber 63.
Reference numeral 65 is a recording head which has an ejection energy generating means and ejects the ink to the cloth containing a polyamide fiber which is disposed so as to confront the ejection hole surface, thereby carrying out the recording. Reference numeral 66 is a carriage on which the recording head 65 is mounted and which can move the recording head 65. The carriage 66 is slidably engaged with a guide axis 67, and a part of the carriage 66 is connected (not shown) with a belt 69 which can be driven by a motor 68, whereby the carriage 66 can be moved along the guide axis 67 to the recording region for the recording head 65 and a region adjacent thereto.
Reference numeral 51 is a cloth feeder for feeding the cloth containing the polyamide fiber, and reference numeral 52 is a cloth feed roller which can be driven by a motor not shown in the figure. According to this constitution, the cloth containing the polyamide fiber is fed to a position which confronts the election hole surface of the recording head, and as the recording proceeds, the cloth is forwarded to a cloth discharge section where cloth discharge rollers 53 are arranged.
In the above-mentioned constitution, when the recording head 65 returns to the home position at the time of the end of the recording or the like, the cap 62 of the head recovery portion 64 retracts from the moving passage of the recording head 65, but the blade 61 protrudes into the moving passage. As a result, the ejection hole surface of the recording head 65 is wiped. In this connection, when the cap 62 comes in contact with the election hole surface of the recording head 65 to cap the ejection hole surface, the cap 62 moves so as to protrude into the moving passage of the recording head.
In the case that the recording head 65 moves from the home position to a recording start position, the cap 62 and the blade 61 are at the same position as in the above-mentioned wiping operation. As a result, even at the time of this movement of the recording head 65, the ejection hole surface of the recording head 65 can be wiped.
The movement of the recording head to the home position adjacent to the recording region is carried out at a predetermined interval at the end of the recording, at the time of ejection recovery and during the movement of the recording head in the recording region, and the above-mentioned wiping operation is made during this movement.
FIG. 5 shows one example of an ink cartridge in which an ink fed to the head via an ink feed member such as a tube is contained. Here, reference numeral 40 is an ink containing section containing the ink to be fed, and for example, it is an ink bag. At the tip of the ink bag 40, a plug 42 made of a rubber is mounted. The ink in the ink bag 40 can be fed to the head by inserting a needle (not shown) into this plug 42. Reference numeral 44 is an ink absorber for absorbing and receiving a waste ink. In the present invention, the surface of the ink absorber which comes in contact with the ink is preferably made of polyolefin, particularly polyethylene. The ink jet recording apparatus for use in the present invention is not limited to the above-mentioned apparatus in which the head and the ink cartridge are separated. Therefore, an apparatus in which they are integrally associated as shown in FIG. 6 can also be used.
In FIG. 6, reference numeral 70 is a recording unit, and in this recording unit, an ink containing section for containing the ink, for example, an ink absorber is placed. The ink absorber is constituted so that the ink in the ink absorber can be ejected in the form of ink droplets through the head portion 71 having a plurality of orifices. As the material of the ink absorber, it is preferable for the present invention to use polyurethane. Reference numeral 72 is an air passage for communicating the interior of the recording unit 70 to the atmosphere. This recording unit 70 can also be used in place of the recording head shown in FIG. 4 and it is detachably attached to the carriage 66.
EXAMPLE
Next, the present invention will be described more detail in reference to examples and comparative examples, but the scope of the present invention should not be limited to these examples. In this connection, it is to be noted that parts and percent are based on weight, unless otherwise specified.
Preparation of Ink
Ink A
______________________________________Acid dye (C. I. Acid Black 24) 6 partsThiodiglycol 22 partsDiethylene glycol 11 partsWater 61 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a black ink A.
Ink B
______________________________________Direct dye (C. I. Direct Yellow 86) 5 partsDiethylene glycol 30 partsWater 65 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a yellow ink B.
Ink C
______________________________________Acid dye (C. I. Acid Orange 95) 7 partsDiethylene glycol 29 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain an orange ink C.
Ink D
______________________________________Acid dye (C. I. Acid Red 266) 5 partsDiethylene glycol 31 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a red ink D.
Ink E
______________________________________Compound (6) 5 partsDiethylene glycol 31 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a magenta ink E.
Ink F
______________________________________Acid dye (C. I. Acid Blue 78) 6 partsDiethylene glycol 33 partsWater 61 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a blue ink F.
Ink G
______________________________________Direct dye (C. I. Direct Blue 199) 6 partsDiethylene glycol 33 partsWater 61 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a cyan ink G.
Ink H
______________________________________Compound (4) 3 partsCompound (5) 2 partsDiethylene glycol 33 partsWater 62 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a black ink H.
Ink a
______________________________________Acid dye (C. I. Acid Black 194) 6 partsThiodiglycol 22 partsDiethylene glycol 11 partsWater 61 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a black ink a.
Ink b
______________________________________Direct dye (C. I. Direct Black 154) 5 partsDiethylene glycol 33 partsWater 62 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a black ink b.
Ink c
______________________________________Direct dye (C. I. Direct Yellow 106) 5 partsDiethylene glycol 30 partsWater 65 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a yellow ink c.
Ink d
______________________________________Direct dye (C. I. Direct Orange 102) 7 partsDiethylene glycol 29 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain an orange ink d.
Ink e
______________________________________Acid dye (C. I. Acid Red 336) 5 partsDiethylene glycol 31 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a red ink e.
Ink f
______________________________________Direct dye (C. I. Direct Red 9) 5 partsDiethylene glycol 31 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a magenta ink f.
Ink g
______________________________________Direct dye (C. I. Direct Blue 160) 6 partsDiethylene glycol 33 partsWater 61 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.7 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a blue ink g.
Ink h
______________________________________Acid dye (C. I. Acid Blue 23) 5 partsDiethylene glycol 31 partsWater 64 parts______________________________________
All of the above-mentioned components were mixed, and the pH of the mixed solution was adjusted to 7.5 with sodium hydroxide, followed by stirring for 2 hours. Afterward, the solution was filtered through a fluoropore filter FP-100 (trade name, made by Sumitomo Electric Industries, Ltd.) to obtain a cyan ink h.
Example 1
A fabric comprising 100% of nylon was first immersed in a 15% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 10%.
Inks A, B, C and D were fed to a color bubble jet printer BJC820J (trade name, made by Canon Inc.) having an election rate of 12 m/sec, and two colors of all combinations of black and other colors were shot in a patch (2×4 cm) of the above-mentioned fabric in shot-in quantities of 2, 4, 6 and 8 nl/mm 2 so that an overlapped portion and a boundary portion might be observed, while the shot-in order of the inks was changed. In this case, same three patches were prepared in respective cases. Two of the three patches were superposed upon each other, and fixing was then carried out by subjecting them to a steaming treatment at 100° C. for 30 minutes. For the one remaining patch, the same treatment was done at 95° C. for 25 minutes. Afterward, they were washed using a neutral detergent. Next, evaluation was made by observing sharpness along the edge of a boundary, coloring properties of an overlapped portion at the time of the change of the shot-in order, and a difference of color development among the three printed patches. The results are shown in Table 1.
Example 2
A fabric comprising 85% of nylon and 15% of rayon was first immersed in a 30% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 25%.
This fabric was printed by the same procedure as in Example 1, and then similarly evaluated. The results are shown in Table 1.
Example 3
A fabric comprising 100% of silk was first immersed in an aqueous solution containing 3% of polyvinyl alcohol and 5% of calcium chloride, squeezed to a pickup of 30%, and then dried so that a moisture content might be 21%.
This fabric was printed with inks E, F, G and H by the same procedure as in Example 1, and then similarly evaluated. The results are shown in Table 1.
Example 4
A fabric comprising 100% of wool was first immersed in a 10% aqueous sodium alginate solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 30%.
This fabric was printed by the same procedure as in Example 3, and then similarly evaluated. The results are shown in Table 1.
Example 5
A mixed fabric comprising 70% of nylon and 30% of polyurethane was first immersed in a 30% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 25%.
This fabric was printed by the same procedure as in Example 3, and then similarly evaluated. The results are shown in Table 1.
Comparative Example 1
The same fabric comprising 100% of nylon as used in Example 1 was first immersed in a 15% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 10%.
This fabric was printed with inks B, C, D and a by the same procedure as in Example 1, and then similarly evaluated. The results are shown in Table 1. As apparent from these results, sharpness along the edge of a printed portion and coloring properties at the time of the change of a shot-in order were poorer than in Example 1, and three printed patches were different in the coloring properties.
Comparative Example 2
The same fabric comprising 100% of silk as used in Example 3 was first immersed in an aqueous solution containing 3% of polyvinyl alcohol and 5% of calcium chloride, squeezed to a pickup of 30%, and then dried so that a moisture content might be 21%.
This fabric was printed with inks E, F, G and b by the same procedure as in Example 3, and then similarly evaluated. The results are shown in Table 1. As apparent from these results, sharpness along the edge of a printed portion and coloring properties at the time of the change of a shot-in order were poorer than in Example 3, and three printed patches were different in the coloring properties.
Comparative Example 3
The same fabric comprising 100% of nylon as used in Example 1 was first immersed in a 15% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 10%.
This fabric was printed with inks B, D, and d by the same procedure as in Example 1, and then similarly evaluated. The results are shown in Table 1. As apparent from these results, sharpness along the edge of a printed portion and coloring properties at the time of the change of a shot-in order were poorer than in Example 1, and three printed patches were different in the coloring properties.
Comparative Example 4
The same fabric comprising 100% of nylon as used in Example 1 was first immersed in a 15% aqueous urea solution, squeezed to a pickup of 30%, and then dried so that a moisture content might be 10%.
This fabric was printed with inks a, c, d and e by the same procedure as in Example 1, and then similarly evaluated. The results are shown in Table 1. As apparent from these results, sharpness along an edge of a printed portion and coloring properties at the time of the change of a shot-in order were poorer than in Example 1, and three printed patches were different in the coloring properties.
Comparative Example 5
The same fabric comprising 100% of silk as used in Example 3 was first immersed in an aqueous solution containing 3% of polyvinyl alcohol and 5% of calcium chloride, squeezed to a pickup of 30%, and then dried so that a moisture content might be 21%.
This fabric was printed with inks b, f, g and h by the same procedure as in Example 3, and then similarly evaluated. The results are shown in Table 1. As apparent from these results, sharpness along the edge of a printed portion and coloring properties at the time of the change of a shot-in order were poorer than in Example 3, and three printed patches were different in the coloring properties.
TABLE 1______________________________________ Coloring properties Difference Difference of color mixing of k/s of k/sSharp- portion in case between two between twoness that shot-in samples printed samples printedof order was under the same under differentEdge*1 changed*2 conditions*3 conditions*4______________________________________Example 2 ∘ ∘ ∘ ∘Example 3 ∘ ∘ ∘ ∘Example 4 ∘ ∘ ∘ ∘Example 5 ∘ ∘ ∘ ∘Example 6 ∘ ∘ ∘ ∘Comp. Ex. 1 Δ Δ Δ xComp. Ex. 2 Δ Δ Δ xComp. Ex. 3 Δ Δ Δ xComp. Ex. 4 x x Δ xComp. Ex. 5 x x Δ x______________________________________ *1: The sharpness along edge of the boundary was judged by visual observation. The evaluation was ranked as follows: ∘: Good Δ: Slightly poor x: Poor *2: The k/s values of the respective color mixing portions were measured, and the coloring properties were evaluated from a difference of the k/s values between the samples printed under the same conditions except that the shotin orders were changed. The evaluation was ranked as follows: ∘: In the case that the maximum difference was less than 1. Δ: In the case that the maximum difference was in the range of from 1 to 2. x: In the case that the maximum difference was more than 2. k/s = (1 - R).sup.2 /2R wherein R is a reflectance at a maximum absorption wavelength. *3: The coloring properties were evaluated from a difference of the k/s value between two samples printed under all the same conditions in accordance with the same ranking as in the abovementioned *2. *4: The evaluation was made on the basis of a difference of the k/s value between two samples printed under the same conditions except that dyeing conditions were changed, in accordance with the same ranking as in the abovementioned *2.
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Provided is an ink jet printing method for printing inks of at least two colors on a cloth by an ink jet system which comprises at least three steps of:
(a) the step of printing, on the cloth, the inks of at least two colors of a black ink and an another ink of at least one color selected from the group consisting of yellow, orange, red, magenta, blue and cyan so that the inks may at least partially overlap,
(b) the step of thermally treating the cloth printed with the inks, and
(c) the step of washing the thermally treated cloth,
said cloth comprising a polyamide fiber,
said black ink containing, as a dyestuff, at least one selected from the group consisting of
C. I. Acid Black 24, 26, 52, 52:1, 109, 155, 172 and 222,
C. I. Direct Black 19, 62 and 113, and a dyestuff represented by the formula (1) ##STR1## wherein M is an alkaline metal, ammonium or an amine, or the formula (2) ##STR2## wherein X is a hydrogen atom, a lower alkyl group or a phenyl group which may be substituted by an SO 3 M group; m is 0 or 1; M is an alkaline metal, ammonium or an amine; each of A, B and C is a benzene ring or a naphthalene ring which may have a substituent, but B and C are not simultaneously the naphthalene rings.
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FIELD OF THE INVENTION
This invention relates to stents, and particularly to bioresorbable stents useful in the treatment of strictures and preventing restenosis disorders.
BACKGROUND
Tubular organs and structures such as blood vessels, the esophagus, intestines, endocrine gland ducts and the urethra are all subject to strictures i.e., a narrowing or occlusion of the lumen. Strictures can be caused by a variety of traumatic or organic disorders and symptoms can range from mild irritation and discomfort to paralysis and death. Treatment is site specific and varies with the nature and extent of the occlusion.
Life threatening stenoses are most commonly associated with the cardiovascular system and are often treated using percutaneous transluminal coronary angioplasty (PTCA). This process reduces the stricture by expanding the artery's diameter at the blockage site using a balloon catheter. However, three to six months after PTCA, approximately 30% to 40% of patients experience restenosis. Injury to the arterial wall during PTCA is believed to be the initiating event causing restenosis and primarily results from vascular smooth muscle cell proliferation and extracellular matrix secretion at the injured site. Restenosis is also a major problem in non-coronary artery disease including the carotid, femoral, iliac, popliteal and renal arteries.
Stenosis of non-vascular tubular structures is often caused by inflammation, neoplasm and benign intimal hyperplasia. In the case of esophageal and intestinal strictures, the obstruction can be surgically removed and the lumen repaired by anastomosis. The smaller transluminal spaces associated with ducts and vessels may also be repaired in this fashion; however, restenosis caused by intimal hyperplasia is common. Furthermore, dehiscence is also frequently associated with anastomosis requiring additional surgery which can result in increased tissue damage, inflammation and scar tissue development leading to restenosis.
Problems with diminished urine flow rates are common in aging males. The most frequent cause is benign prostatic hypertrophy (BPH). In this disease the internal lobes of the prostate slowly enlarge and progressively occlude the urethral lumen. A number of therapeutic options are available for treating BPH. These include watchful waiting (no treatment), several drugs, a variety of so-called “less invasive” therapies, and transurethral resection of the prostate (TURP)—long considered the gold standard.
Urethral strictures are also a significant cause of reduced urine flow rates. In general, a urethral stricture is a circumferential band of fibrous scar tissue which progressively contracts and narrows the urethral lumen. Strictures of this type may be congenital or may result from urethral trauma or disease. Strictures were traditionally treated by dilation with sounds or bougies. More recently, balloon catheters became available for dilation. Surgical urethrotomy is currently the preferred treatment, but restenosis remains a significant problem.
Recent advances in biomedical engineering have led to the development of stenting i.e., mechanical scaffolding, to prevent restenosis and keep the previously occluded lumens open. There are two general types of stents: permanent and temporary. Temporary stents can be further subdivided into removable and absorbable.
Permanent stents are used where long term structural support or restenosis prevention is required, or in cases where surgical removal of the implanted stent is impractical. Permanent stents are usually made from metals such as Phynox, 316 stainless steel, MP35N alloy, and superelastic Nitinol (nickel-titanium).
Stents are also used as temporary devices to prevent closure of a recently opened urethra following minimally invasive procedures for BPH which typically elicit post treatment edema and urethral obstruction. In these cases, the stent will typically not be covered with tissue (epithelialized) prior to removal.
Temporary absorbable stents can be made from a wide range of synthetic bio-compatible polymers depending on the physical qualities desired. Representative bio-compatible polymers include polyanhydrides, polycaprolactone, polyglycolic acid, poly-L-lactic acid, poly-D-L-lactic acid and polyphosphate esters.
Stents are designed to be deployed and expanded in different ways. A stent can be designed to self expand upon release from its delivery system, or it may require application of a radial force through the delivery system to expand the stent to the desired diameter. Self expanding stents are typically made of metal and are woven or wound like a spring. Synthetic polymer stents of this type are also known in the art. Self-expanding stents are compressed prior to insertion into the delivery device and released by the practitioner when correctly positioned within the stricture site. After release, the stent self expands to a predetermined diameter and is held in place by the expansion force or other physical features of the device.
Stents which require mechanical expansion by the surgeon are commonly deployed by a balloon-type catheter. Once positioned within the stricture, the stent is expanded in situ to a size sufficient to fill the lumen and prevent restenosis. Various designs and other means of expansion have also been developed. One variation is described in Healy and Dorfman, U.S. Pat. No. 5,670,161. Healy and Dorfman disclose the use of a bio-compatible stent that is expanded by a thermo-mechanical process concomitant with deployment.
Approximately one-third of all patients undergoing surgery, catheterization or balloon dilation to repair bulbar urethral strictures experience restenosis. In these patients the use of urethral stents has provided satisfactory relief from symptoms. (Badlani, G. H., et al., UroLume® Endourethral Prosthesis for the Treatment of Urethral Stricture Disease: Long-term Results of the North American Multicenter UroLume ® Trial. Urology: 45:5, 1993). Currently, urethral stents are composed of bio-compatible metals woven into a tubular mesh or wound into a continuous coil and are inserted endoscopically after opening the stricture by urethrotomy or sequential dilation. The stent is initially anchored in place through radial force as the stent exerts expansion pressure against the urethral wall. With woven stents epithelial cells lining the urethra begin to grow through the stent's open weave between six and 12 weeks after insertion, thereby permanently securing the stent.
For most patients this is a one time process without complication. However, some men experience post insertion complications including stent migration, excessive epithelialization, and stent encrustation. In some cases excessive epithelial tissue may be resected transurethrally. In other situations stent removal may be necessary. Depending on the condition of the stent, removal procedures range from a relatively simple transurethral procedure to open surgery with excision and urethroplasty. All complications increase patent discomfort and health care costs.
Recently, a number of bio-compatible, bioresorbable materials have been used in stent development and in situ drug delivery development. Examples include U.S. Pat. No. 5,670,161 (a thermo-mechanically expanded biodegradable stent made from a co-polymer of L-lactide and ε-caprolactone), U.S. Pat. No. 5,085,629 (a bioresorbable urethral stent comprising a terpolymer of L-lactide, glycolide and ε-caprolactone) U.S. Pat. No. 5,160,341 (a resorbable urethral stent made from polylactic acid or polyglycolic acid), and U.S. Pat. No. 5,441,515 (a bio-erodible drug delivery stent and method with a drug release layer).
The bioresorbable stents discussed in these earlier references are all designed and made from co-polymers, which is in sharp contrast to the use of the blending process of the present invention. The blending aspect of the present invention overcomes disadvantages associated with the prior art co-polymers insofar as it is more cost effective than co-polymerization, which typically must be out-sourced by end product stent manufacturers. The blending process also offers greater versatility insofar as the raw materials used in earlier co-polymeric stents were fixed in design and physical qualities. Any changes in the polymer formulation necessary to improve stent performance using a co-polymerization process can only be accomplished by having new co-polymer materials manufactured by the supplier. This often results in excessive delays in product development and significantly increases research and development costs.
Furthermore, co-polymers of L-lactide and ε caprolactone are typically mostly amorphous and may be more susceptible to hydrolytic decomposition than a blend of poly-L-lactide and poly-ε-caprolactone of similar composition. Additionally, it is more difficult to maintain consistency in the manufacture of co-polymers than homopolymers, resulting in significant batch to batch variation in copolymers.
Consequently, there remains a need for a self expanding stent with stable and predictable physical characteristics suited for a wide variety of physiological conditions. In particular, there is a need for a stent making process and stent design that can be easily and cost effectively implemented for any number of application requirements.
SUMMARY
It is an object of the present invention to provide a blended polymeric stent providing short to intermediate-term functional life in vivo.
It is another objective of the invention to provide a medical device that remains bio-compatible during prolonged intimate contact with human tissue and is fully bioresorbable, thus eliminating the need for costly, painful and potentially damaging post insertion removal.
Furthermore, it is another object of the present invention to provide a medical device that will temporarily restore, or maintain patency of the male urethra while permitting voluntary urination, thereby liberating the patient from catheterization, permitting voluntary urination, and reducing the risk of catheter associated urinary tract infections.
These and other objectives not specifically enumerated here are addressed by a self expanding, bioresorable stent and stent making process in accordance with the present invention, which stent may include a tubular-shaped member having first and second ends and a walled surface disposed between the first and second ends. The walled surface may include a substantially helical-shape of woven monofilaments wherein the monofilaments are composed of a blend of bioresorbable, bio-compatible polymers.
Another embodiment of the present invention may include a bioresorbable stent having a radially self expanding, tubular shaped member which may also expand and contract along its horizontal axis (axially retractable). The stent having first and second ends and a walled surface disposed between the first and second ends. The walled surface may include a plurality of substantially parallel pairs of monofilaments 14 with the substantially parallel pairs of monofilaments woven in a helical shape. The stent is woven such that one-half of the substantially parallel pairs of monofilaments are wound clockwise in the longitudinal direction and one-half of the substantially parallel pairs of monofilaments are wound counterclockwise in the longitudinal direction. This results in a stent having an alternating, over-under plait of the oppositely wound pairs of monofilaments.
Still another embodiment of the present invention may include a radially expandable, axially retractable bioresorbable stent made from a blend of at least two bio-compatible, bioresorbable polymers injection molded into a substantially tubular shaped device. The injection molded or extruded tubular shape device may have first and second ends with a walled structure disposed between the first and second ends and wherein the walled structure has fenestrations therein.
According to another aspect of the invention, a method for producing a stent may include blending at least two bioresorbable, bio-compatible polymers in a predetermined ratio to form a blend and producing a monofilament from the blend by an extrusion process. The monofilament may have a diameter between approximately 0.145 mm and 0.6 mm. The monofilaments may be extruded to a draw ratio of between approximately 3.5 to 5.5, preferably about 4.5. The monofilaments may be braided into a substantially tubular device. Then the tubular device may be annealed at a temperature between the glass transition temperature and melting temperature of the blended polymers for between five minutes and 18 hours.
Additional objects and advantages of the present invention and methods of construction of same will become readily apparent to those skilled in the art from the following detailed description, wherein only the preferred embodiments are shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention. As will be realized, the invention is capable of modification in various respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of the invention is hereafter described by non-limiting examples with specific reference being made to the drawings in which:
FIG. 1 depicts a 30 strand version of the bioresorbable stent in accordance with a preferred embodiment of the present invention;
FIG. 2 depicts a 48 strand version of the bioresorbable stent in accordance with a preferred embodiment of the present invention;
FIG. 3 depicts a bioresorbable stent with fenestrations in accordance with a preferred embodiment of the present invention;
FIG. 4 diagramatically depicts the manufacturing method of the first embodiment of the present invention;
FIG. 5 diagramatically depicts the manufacturing method of the second embodiment of the present invention;
FIG. 6 graphically compares compression resistance of a 48 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a first compression cycle in air at ambient temperature;
FIG. 7 graphically compares compression resistance of a 48 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a second compression cycle in air at ambient temperature with a one minute hold. The stents in this test were held in the fully compressed state for one minute during the first compression-expansion cycle;
FIG. 8 graphically compares the self expansion force of a 48 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a first compression and expansion cycle in air at ambient temperature with a one minute hold during the first cycle;
FIG. 9 graphically compares self expansion force of a 48 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a second compression and expansion cycle in air at ambient temperature with a one minute hold during each cycle;
FIG. 10 graphically compares compression resistance of a 30 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a first compression cycle in air at ambient temperature;
FIG. 11 graphically compares compression resistance of a 30 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a second compression and expansion cycle in air at ambient temperature with a one minute hold during the first cycle;
FIG. 12 graphically compares self expansion force of a 30 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a first compression and expansion cycle in air at ambient temperature with a one minute hold;
FIG. 13 graphically compares self expansion force of a 30 monofilament stent in accordance with a preferred embodiment of the present invention versus the UroLume® in a second compression and expansion cycle in air at ambient temperature with a one minute hold during each cycle.
DETAILED DESCRIPTION
A bioresorbable stent 10 , 14 , in accordance with a first embodiment of the present invention comprises either woven monofilaments (FIGS. 1 and 2) or, in a second embodiment 23 an injection molded or extruded fenestrated tube (FIG. 3) formed from blends of at least two bioresorbable, bio-compatible polymers. These polymers may include, but are not limited to poly-L-lactide (PLLA), poly-D,L-lactide (PDLA) and poly-ε-caprolactone (PCL). A preferred polymeric substrate is made by blending PLLA and PCL.
This stent 10 , 14 , 23 is used for temporary obstruction relief associated with various disease conditions of the bulbar, membranous or prostatic urethra. Moreover, the stent 10 , 14 , 23 is designed to be self-expanding and can be formulated to have different nominal functional lives. As the urothelium covered stent 10 , 14 , 23 reaches the end of its usable life, it is slowly absorbed into the surrounding tissues and metabolized via the tricarboxylic acid cycle and is excreted as carbon dioxide and water. If the stent 10 , 14 , 23 remains uncovered by urothelium, it will slowly disintegrate and be excreted in the urine flow.
In the first embodiment the stent 10 , 14 is a tubular shaped member having first and second ends 17 , 18 , 17 ′, 18 ′ and a walled surface 19 , 19 ′ disposed between the first and second ends 17 , 18 , 17 ′, 18 ′. The walls are composed of extruded polymer monofilaments woven into a braid-like embodiment. In the second embodiment, the stent 23 is injection molded or extruded. Fenestrations 24 are molded, laser cut, die cut, or machined in the wall of the tube.
The stent 10 , 14 , 23 is provided as a sterile device that is compressed to a first diameter of between approximately 6 mm to 10 mm and inserted into a reusable delivery tool (not shown) in the operating room immediately before implantation. Once the stent 10 , 14 , 23 is deployed, it self expands outwardly to a variable second diameter conforming to the lumen. The size of the lumen together with the elasticity and circumferential pressure of the surrounding tissues determine the stent's final nominal diameter. The stents' non-compressed, or resting state, diameter, is between approximately 12 mm to 18 mm.
The method for formulation of the stent 10 , 14 will now be described (FIG. 4 ). The PLLA and PCL polymers are first dry blended 25 under an inert atmosphere, then extruded in a rod form 26 . In a preferred embodiment of the present invention, granules of PLLA and PCL are dry-blended with a PLLA/PCL ratio of between approximately 80:20 to 99:1, preferably 90:10.
The blended PLLA and PCL polymer rod is pelletized 27 then dried 28 . The dried polymer pellets are then extruded 29 forming a coarse monofilament which is quenched 30 . The extruded, quenched, crude monofilament is then drawn into a final monofilament 31 with an average diameter from approximately 0.145 mm to 0.6 mm, preferably between approximately 0.35 mm and 0.45 mm. Approximately 10 to approximately 50 of the final monofilaments 31 are then woven 32 in a plaited fashion with a braid angle 12 , 16 from about 100 to 150 degrees on a braid mandrel of about 3 mm to about 30 mm in diameter. The plaited stent 10 , 14 is then removed from the braid mandrel and disposed onto an annealing mandrel having an outer diameter of equal to or less than the braid mandrel diameter and annealed 33 at a temperature between about the polymer-glass transition temperature and the melting temperature of the polymer blend for a time period between about five minutes and about 18 hours in air, an inert atmosphere or under vacuum. The stent 10 , 14 is then allowed to cool and is then cut 34 .
The manufacturing flow chart of stent 23 is presented in FIG. 5 . In the first step 37 a blend is made of PLLA and PDLLA in a ratio of between approximately 50:50 to 70:30, preferable 60:40. The blending is done in an inert atmosphere or under vacuum. The blended PLLA and PDLLA is extruded in rod form 38 , quenched 38 , then pelletized 39 . Typically, the polymer pellets are dried 40 , then melted in the barrel of an injection molding machine 41 and then injected into a mold under pressure where it is allowed to cool and solidify 42 . The stent is then removed from the mold 43 . The stent tube may, or may not, be molded with fenestrations in the stent tube.
In a preferred embodiment of the fenestrated stent 23 the tube blank is injection molded or extruded, preferably injection molded, without fenestrations. After cooling, fenestrations are cut into the tube using die-cutting, machining or laser cutting, preferably laser cutting 43 a. The resulting fenestrations, or windows, may assume any shape which does not adversely affect the compression and self-expansion characteristics of the final stent.
The stent is then disposed on an annealing mandrel 44 having an outer diameter of equal to or less than the innner diameter of the stent and annealed at a temperature between about the polymer-glass transition temperature and the melting temperature of the polymer blend for a time period between about five minutes and 18 hours in air, an inert atmosphere or under vacuum 44 . The stent 23 is allowed to cool 45 and then cut as required 46 .
The blends of PCL, PLLA, and PDLLA made in accordance with the present invention have been found to provide improved processability and stability versus a co-polymerization process. Without intending to be bound by this theory, one possible explanation for the improvements can be attributed to the difference in physical states in which the individual polymers exist once combined. Typically, co-polymers are mostly amorphous compositions, but blends of PLLA and PCL may exist as different size semicrystalline domains of each polymer with a greater percentage of PCL at the surface. Morphology of both domains may be manipulated by thermal treatments. This increased concentration of PCL at the surface is believed to contribute to the blended composition's increased resistance to hydrolytic attack. Control over the morphology of the final polymer blend is an advantage to providing the improved physical and biological properties of the stent.
The stent's 10 , 14 , 23 mechanical properties and strength generally increase proportionally with the molecular weight of the polymers used. The optimum molecular weight range is selected to accommodate processing effects and yield a stent with desired mechanical properties and in vivo degradation rate. The preferred PLLA raw material of the stent 10 , 14 , 23 should have an inherent viscosity of approximately≧4.5 dl/g (preferably≧8.0 dl/g) and a number average molecular weight of approximately 450,000 daltons or greater (preferably≧750,000 daltons). The preferred PCL raw material of the stent 10 , 14 , should have an inherent viscosity of approximately≧1.6 dl/g (preferably≧3.0 dl/g) and a number average molecular weight of approximately 100,000 daltons or greater (preferably≧200,00 daltons). The preferred PDLLA raw material should have an inherent viscosity of≧3.0 dl/g (preferably≧5.0 dl/g) and a number average molecular weight of approximately 100,000 daltons or greater (preferably≧500,000 daltons). Inherent viscosity is determined under the following standard conditions: 0.1% solution in chloroform at 25° C. using a Cannon-Fenske capillary viscometer.
Two physical qualities of the polymer or polymer blend used to fabricate the stent 10 , 14 , 23 play important roles in defining the overall mechanical qualities of the stent 10 , 14 , 23 : tensile strength and tensile modulus. Tensile strength is defined as the force per unit area at the breaking point. It is the amount of force, usually expressed in pounds per square inch (psi), that a substrate can withstand before it breaks, or fractures. The tensile modulus, expressed in psi, is the force required to achieve one unit of strain which is an expression of a substrate's stiffness, or resistance to stretching, and relates directly to a stent's self-expansion properties.
The PLLA and PCL blend in the woven embodiment possesses a tensile strength in the range from about 40,000 psi to about 120,000 psi with an optimum tensile strength for the stent 10 , 14 , of approximately between 60,000 to 120,000 psi. The tensile strength for the fenestrated stent 23 is from about 8,000 psi to about 12,000 psi with an optimum of about 8,700 psi to about 11,600 psi. The tensile modulus of polymer blends in both embodiments ranges between approximately 400,000 psi to about 2,000,000 psi. The optimum range for a stent application in accordance with the present invention is between approximately 700,000 psi to approximately 1,200,000 psi for the woven embodiment and approximately 400,000 psi to 800,000 psi for the fenestrated embodiment.
In one embodiment, thirty spools are wound with monofilament and a 30 strand braid is prepared (FIG. 1 ). The monofilaments 35 are interwoven in a helical pattern on a round bar mandrel such that one-half of the monofilaments are wound clockwise. Each monofilament intersects 11 the oppositely wound monofilaments in an alternating over-under pattern such that a tubular braid is made with crossing angles 12 between overlapping monofilaments in the longitudinal or axial direction (when the stent 10 is in a non-compressed, resting position) of 100-150 degrees. The braided device is transferred to an annealing mandrel having a diameter equal to or less than the round braiding mandrel. The ends 13 of the braid are compressed or extended to yield the optimum post annealing geometry; then the ends are secured to the annealing mandrel. The device is then annealed by heating the annealing bar and stent to 90° C. for one hour in an inert atmosphere followed by a second heating cycle for 2 hours at 140° C. in the same inert atmosphere. The stent is not allowed to cool between heating cycles. Finally, the stent is cooled, removed from the annealing bar and cut to the desired length. FIG. 4 diagramatically depicts this process.
In another preferred embodiment the stent 14 is made as described above except that a 24 carrier weave is used to produce a 48 strand device as shown in FIG. 2 . Twenty-four monofilament pairs 36 are interwoven in a helical pattern on a round bar mandrel such that one-half of the monofilament pairs are wound clockwise and one-half are wound counter clockwise. Each monofilament pair intersects 15 the oppositely wound monofilament pairs in an alternating over-under pattern such that a tubular braid is made with crossing angles 16 between overlapping pairs of monofilaments in the longitudinal or axial direction (when the stent is in a non-compressed, resting position) of 100-150 degrees.
In yet another preferred embodiment a non-toxic radio-opaque marker is incorporated into the polymer blend prior to extruding the monofilaments used to weave the stent. Examples of suitable radio-opaque markers include, but are not limited to, barium sulfate and bismuth trioxide in a concentration of between approximately 5% to 30%.
Two important physical properties required of a self-expanding stent are compression resistance and self-expansion, or radial expansion, force. Compression resistance relates to the stent's ability to withstand the surrounding tissue's circumferential pressure. A stent with poor compression resistance will not be capable of maintaining patency. Self expansion force determines the stent's capacity to restore patency to a constricted lumen once inserted. The combination of self-expansion with resistance to compression are competing qualities and must be carefully considered when a stent is designed. The combination of polymer blending, processing, (including post-weaving annealing) and overall stent design and construction results in a superior stent 10 , 14 , 23 capable of surpassing the best performing metal stents found in the prior art.
Compression relaxation tests were conducted on an Instron test machine using a specially designed test fixture and a Mylar® collar. The test fixture consisted of a pair of freely rotating rollers separated by a 1 mm gap. The collar was a composite film of Mylar® and aluminum foil. Each 30 mm long stent was wrapped a 25 mm wide collar and the two ends of the collar were passed together through the gap between the rollers; a pulling force was applied to the ends of the collar, thus compressing the stent radially.
The raw data of crosshead displacement versus force was treated to obtain the constrained diameter versus force curve of the stent specimen. In this test method, the stent was subjected to two cycles of the following three sequential steps. First, the stent was compressed to 7 mm OD at a controlled speed. This portion of the test characterized the compression resistance of the stent. Second, the stent was held in the compressed state for a given duration, typically one minute. This portion of the test characterized the force decay or loss of recovery force. Third, the constraint on the stent was relaxed at a controlled rate. This portion of the test characterized the self-expansion force of the stent. The test may be conducted in air at room temperature, in water at a set temperature, or in an environmental chamber.
The 48 monofilament stent 14 in FIG. 2 can be compressed to a nominal diameter of approximately 6 mm to 7 mm and exerts a radial self-expansion force of approximately 18 N after release from the insertion tool. The fully deployed stent 14 expands to a diameter sufficient to restore or maintain patency in the patient. Returning the expanded stent to the fully compressed state requires approximately 25 N of circumferential pressure.
In another embodiment of the present invention, the 30 monofilament stent 10 can be compressed to a nominal diameter of approximately 6 mm to 7 mm which exerts a radial self-expansion force of approximately 25 N after release from the insertion tool. The fully deployed stent expands to a diameter sufficient to restore or maintain patency in the patient. Returning the fully expanded stent to the fully compressed state requires approximately 35 N of circumferential pressure. These high levels of radial expansion force and resistance to compression are benefits of the manufacturing process and stent design in accordance with the present invention. The all metal UroLume® stent manufactured by American Medical Systems of Minneapolis, Minn. has been tested to have an expansion force of 5 N at 7 mm and withstands 5 N of circumferential pressure at that diameter.
Furthermore, it was determined that bioresorbable stents 10 , 14 , 23 maybe manufactured in accordance with the present invention which are capable of retaining their initial self-expansion force and resistance to compression for a minimum of up to twelve weeks after deployment.
FIG. 6 graphically compares the compression resistance of one embodiment of the present invention (designated CL10-48Strand) with the all metal urethral stent marketed by American Medical Systems under the trademark UroLume®. As illustrated, the present invention demonstrates superior compression resistance throughout the entire range of stent outer diameters (OD). Each stent was subjected to two rounds of compression and expansion to simulate conditions during actual use. The starting point in these two rounds of compression and expansion represents the stent in resting state prior to insertion into the application device. The first compression represents the forces used to compress the device into the applicator. The first expansion and the second compression simulate conditions exerted by and on the stent following release from the applicator and in situ circumferential pressures, respectively. The maximum compression resistance of the UroLume® at 7 mm was 6 N compared with 26 N at 7 mm for the stent made in accordance with the present invention. FIG. 7 compares the same two stents subjected to a second compression test. Similar results were obtained.
FIGS. 8 and 9 depict the relative self expansion forces of the UroLume® stent and the 48 strand embodiment of the present invention during the first and second expansion cycles, respectively. At every corresponding diameter over the entire range of both tests the 48 monofilament, polymeric blend of the present invention demonstrated self expansion forces greater than or equal to that of the all metal UroLume® stent.
FIG. 10 graphically compares the compression resistance of another embodiment of the present invention (designated CL10-30Strand) with the all metal urethral stent marketed by American Medical Systems under the trade mark UroLume®. As illustrated, the present invention demonstrates superior compression resistance throughout the entire range of stent outer diameters (OD). The maximum compression resistance of the UroLume® at 7 mm was 6 N compared with 35 N at 7 mm for the present invention. FIG. 11 compares the same two stents subjected to a second round of compression tests; similar results were obtained.
FIGS. 12 and 13 depict the relative self expansion forces of the UroLume® stent and the 30 monofilament embodiment made in accordance with the present invention. The 30 monofilament, polymeric blend demonstrated self expansion forces greater than or equal to that of the all metal UroLume® stent throughout the entire OD range during both the first and second expansion cycles.
From the foregoing description, one skilled in the art can readily ascertain the essential characteristics of the invention and, without departing from the spirit and scope thereof, can adapt the invention to various usages and conditions. Changes in the form and substitution of equivalents are contemplated as circumstances may suggest or render expedient, and although specific terms have been employed herein, they are intended in a descriptive sense and not for purposes of limitation. Furthermore, any theories attempting to explain the mechanism of actions have been advanced merely to aid in the understanding of the invention and are not intended as limitations, the purview of the invention being delineated by the following claims.
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A bio-compatible and bioresorbable stent is disclosed that is intended to restore or maintain patency following surgical procedures, traumatic injury or stricture formation. The stent is composed of a blend of at least two polymers that is either extruded as a monofilament then woven into a braid-like embodiment, or injection molded or extruded as a tube with fenestrations in the wall. Methods for manufacturing the stent are also disclosed.
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BACKGROUND
Over time, as the performance of rack mounted computer systems has increased, the amount of heat generated by various computer system components has increased. This, in turn, requires enhanced cooling to maintain required operating temperatures. The most common approach to computer system cooling is the use of fans. However, with the ever-increasing power budget and space constraints of rack mounted computer systems, available cooling solutions are limited. Because space constraints restrict the physical size of fans, a common solution is the use of fans with high revolutions per minute (RPM). However, high RPM fans significantly increase the amount of vibration generated throughout the computer system. Conventionally, computer servers are thin, and there is very little tolerance between the individual hardware racks within the computer system.
The design of fan modules are becoming increasingly complex and ever-increasing requirements are being imposed on the design. Fan modules need to be easily replaced FRUs (Field-Replaceable Units), and have tool-less installation and removal. Installation also needs to be fool-proof, to prevent incorrect installation of fan modules. In addition, fan modules require mechanical isolation to prevent transmission of mechanical vibration to sensitive Hard Disk Drive (HDD) modules.
FIG. 1 shows a conventional example of fan module. In FIG. 1 , the fan module ( 100 ) is fixed within a bracket ( 102 ). The bracket ( 102 ) is a tool-less fan attachment into which the fan module ( 100 ) is placed so that the vibration caused by the fan (within the fan module ( 100 )) rotating at high speeds is isolated within the bracket ( 102 ). The bracket ( 102 ) is typically placed within the chassis of the computer system, as can be seen in FIG. 1 .
SUMMARY
In general, in one aspect, the invention relates to a fan module, comprising a housing for receiving a fan, a connector configured to mate with a connector housing, and a vibration pad configured to isolate vibrations of the fan from transferring through the fan module, wherein the fan module is configured to receive an alignment attachment standoff.
Other aspects of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows a conventional fan bracket.
FIGS. 2-4 show fan modules in accordance with one or more embodiments of the invention.
FIGS. 5-6 show placement of fan modules in accordance with one or more embodiments of the invention.
FIGS. 7-8 show a process of installation of fan modules in accordance with one or more embodiments of the invention
DETAILED DESCRIPTION
Specific embodiments of the invention will now be described in detail with reference to the accompanying figures. Like elements in the various figures are denoted by like reference numerals for consistency.
In the following detailed description of embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
In general, embodiments of the invention relate to an improved fan module with tool-less placement, which can be used even in restricted spaces within computer systems. Particularly, embodiments of the invention provide a self-aligning, fool-proof fan module that can be easily installed in any area of a computer system.
FIG. 2 shows a fan module ( 200 ) in accordance with one or more embodiments of the invention. The fan module ( 200 ) is a tool-less field replacement unit (FRU). A fan ( 202 ) is placed inside the fan module ( 200 ). In other words, the fan module ( 200 ) is a housing that receives a fan ( 202 ). More specifically, in one or more embodiments of the invention, the walls of the fan module ( 200 ) are connectable to the fan ( 202 ). In one or more embodiments of the invention, the fan module ( 200 ) may be made out of sheet metal material. Sheet metal requires a small wall section to implement, and simple screws ( 208 ) can be used to attach the various parts of the fan module ( 200 ) to the fan ( 202 ). Those skilled in the art will appreciate that the fan module may also be made out of alternate materials, such as plastic, rubber, or any other suitable material. Further, those skilled in the art will appreciate that any type of connector may be used instead of screws to attach the fan module to the fan.
In one or more embodiments of the invention, the fan ( 202 ) may snap into the fan module ( 200 ) without any need for fixing or attaching the fan ( 202 ) into the fan module ( 200 ). Thus, the fan module ( 200 ) provides fool-proof assembly of the fan ( 202 ) into the fan module ( 200 ). In addition, as can be seen in FIG. 2 , the fan module ( 200 ) includes a fan extraction tab ( 206 ). The fan extraction tab ( 206 ) provides a visual indication of the presence of the fan module ( 200 ), as the fan module ( 200 ) may be hidden from plain view when placed in a corner, underneath another component, or in a limited space area within the computer system. In addition, the fan extraction tab ( 206 ) allows for removal of the fan module ( 200 ) by pulling on the fan extraction tab ( 206 ). The fan extraction tab ( 206 ) may be made out of any material, such as plastic, rubber, laminate, foam, metal, wood, or any other suitable material. In one or more embodiments of the invention, a label may be printed onto the fan extraction tab ( 206 ) to identify the type of fan ( 202 ) contained within the fan module ( 200 ). The label may be printed in color for easy detection of the fan module ( 202 ).
Those skilled in the art will appreciate that although the fan extraction tab is shown in FIG. 2 as an elongate rectangular component, any type of extraction mechanism may be attached to the fan module to allow for easy removal of the fan module. For example, a circular ring, a handle of any shape, or a type of label may be used as a fan extraction tab. If a wooden or other material handle is used, then text identifying the type of fan contained in the fan module may be molded or carved into the handle.
FIG. 3 shows an alternate view of the fan module ( 200 ) in accordance with one or more embodiments of the invention. The view in FIG. 3 focuses on a connector ( 302 ) that is part of the fan module ( 200 ). In one or more embodiments of the invention, the connector ( 302 ) is a self-aligning connector that allows for fool-proof installation of the fan in a server rack. The connector may be any type of connector that mates with a corresponding connector housing (not shown). Thus, in one or more embodiments of the invention, the connector ( 302 ) may serve as a retention snap that holds the fan module ( 200 ) in place such that the fan module ( 200 ) cannot be removed from its installed location without the release of the retention snap (i.e., the connector ( 302 )). However, because not all computer chassis, server racks, or systems are made to be the same, the connector ( 302 ) may also be a floating connector that provides some tolerance and room for movement within the connector housing of the computer chassis. As a result, the floating feature of the connector ( 302 ) also serves to reduce the transmission of vibration caused by the fan ( 202 ) to other components of the system. Thus, in one or more embodiments of the invention, a retention snap of the fan module ( 200 ) also serves as a vibration damping device.
FIG. 4 is a view of the fan module ( 200 ) in accordance with one or more embodiments of the invention. More specifically, FIG. 4 shows vibration isolation pads ( 402 ) included on a side of the fan module ( 200 ). The vibration isolation pads ( 402 ) serve to isolate the vibration caused by the high-speed rotation of the fan ( 202 ) within the fan module ( 200 ) and prevent the transmission of vibration to near-by hardware components, such as hard disk drives, etc. That is, the vibration isolation pads ( 402 ) dampen the fan vibration. In addition, the vibration isolation pads ( 402 ) provide the force necessary to retain the fan module ( 200 ) in place. In one or more embodiments of the invention, the vibration isolation pads may be on the same wall of the fan module as the alignment feature that aligns with the fan attachment standoffs (discussed below in FIG. 5 ). The vibration pads may be made from rubber, foam, elastomer, plastic, or any other vibration-absorbing material.
In one or more embodiments of the invention, because the fan module is fitted within a restricted space in a computer system, the vibration isolation pads may be squeezed into place when installation of the fan module ( 200 ) takes place. That is, the vibration pads are initially undeformed on the fan module, but become deformed when the fan module is installed into a computer chassis or other restricted space. Thus, the vibration isolation pads ( 402 ) provide a tolerance of the available height of the isolated space in which the fan module ( 200 ) is fitted. In other words, the height of the space into which the fan is installed may be less than a combined height of the fan module and the vibration isolation pad(s). Those skilled in the art will appreciate that although FIG. 4 shows two separate vibration pads, the fan module may include any suitable number of vibration pads on one or more walls of the fan module.
FIG. 5 shows an example of a placement of the fan module in accordance with one or more embodiments of the invention. In particular, FIG. 5 shows fan attachment standoffs ( 502 ) (also called alignment attachment standoffs) under which the sheet metal (or other suitable material) of the fan module slide. That is, in one or more embodiments of the invention, the fan attachment standoffs ( 502 ) are located on the chassis within which the fan module ( 200 ) is placed, and the bottom-side of the fan module ( 200 ) includes an alignment feature that aligns using the fan attachment standoffs ( 502 ) on the chassis. For example, the alignment feature may include a channel, a track, a slot, or other appropriate mechanism for receiving and/or fitting with the fan attachment standoffs. In one or more embodiments of the invention, two fan attachment standoffs ( 502 ) are shown for alignment purposes. Thus, the fan attachment standoffs ( 502 ), together with the connector of FIG. 3 ( 302 ), provide for blind-mating of the fan module ( 200 ) into a location within the chassis of a computer system. Those skilled in the art will appreciate that the fan attachment standoffs may be any size or shape, and the computer chassis may include any number of fan attachment standoffs. For example, the fan attachment standoffs may form a T-shaped alignment on the bottom of the fan module. Alternatively, the fan attachment standoffs may form a rectangular alignment, a circular alignment, or any other suitable shaped alignment for blind mating of the fan module into the computer chassis.
FIG. 6 shows a placement of the fan module within an isolated corner of a computer system in accordance with one or more embodiments of the invention. As can be seen in FIG. 6 , the fan module ( 200 ) is completely hidden from view and only the fan extraction tab ( 206 ) is visible to a person viewing the computer chassis or computer system in which the fan is installed. Embodiments of the invention relate to assembling and installing a fan in such a restricted space, such as an isolated corner as shown in FIG. 6 . Those skilled in the art will appreciate that although embodiments of the invention are suited for installation of a fan in a particularly space-constrained area, embodiments of the invention may apply equally to the installation of fans in an area that is not space-constrained.
FIGS. 7 and 8 show a process for installing a fan module in accordance with one or more embodiments of the invention. More specifically, FIGS. 7 and 8 show an internal view of installing the fan module into a computer chassis in accordance with embodiments of the invention. In FIG. 7 , the fan module ( 700 ) is slid along the fan attachment standoffs ( 702 ) into the isolated corner, as shown. More specifically, the face of the fan module ( 700 ) that includes the protruding floating connector is slid into the connector housing within the isolated corner of the computer chassis. As described above, due to the design of the fan module, the fan module is self-aligning and blind-mating and therefore, installation of the fan into the isolated corner is fool-proof Because the sheet metal aligns with the fan attachment standoffs ( 702 ), and the connector is fitted into the connector housing, the fan module ( 700 ) cannot be installed incorrectly.
FIG. 8 shows the finals step of the installation process, where the fan module ( 800 ) is installed into the corner of the computer chassis, and the fan extraction tab ( 802 ) remains in a visible area of the computer system. In FIG. 8 , the floating connector of the fan module ( 800 ) has snapped into place within the connector housing, and the fan module ( 800 ) is aligned according to the connector and the fan attachment standoffs. Those skilled in the art will appreciate that, particularly in the case of 1U servers, the fan module may be located in a very restricted space.
Embodiments of the invention provide a simple design for a tool-less, low-cost, self-aligning and blind-mating fan module. The fan module of the present invention is a self-aligning, blind mating mounting mechanism with mechanical isolation of minimal vibration transmission through the computer system. In addition, the vibration damping mechanism functions as a retention snap for the fan module, simplifying the design and reducing the part and assembly cost of the fan module. Particularly, the fan module of the invention optimizes the use of space, and can be used in hidden or awkward positions within a computer chassis or server rack. The ergonomic release snap of the fan module allows for easy removal of the fan module from the restricted area in which the module is fitted. The one-part design is able to provide a significant list of features, including fool-proof installation and assembly and easy removal. Further, embodiments of the present invention are scalable to any size fans.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.
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A fan module, including a housing for receiving a fan, a connector configured to mate with a connector housing, and a vibration pad configured to isolate vibrations of the fan from transferring through the fan module, wherein the fan module is configured to receive an alignment attachment standoff.
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RELATED APPLICATION
[0001] This application is a continuation-in-part and claims the benefit of priority under 35 USC §120 of U.S. application Ser. No. 09/877,921, filed Jun. 7, 2001. The disclosure of the prior application is considered part of and is incorporated by reference in the disclosure of this application.
BACKGROUND OF THE INVENTION
[0002] Wavelength division multiplexed systems, in which multiple channels are carried at different wavelengths on the same optical fiber, require adjustable output power to address problems such as optical crosstalk between channels and power balancing of optical signals for optical amplifiers. It is common today to control the output power of a semiconductor laser diode to maintain a constant operational output level, for example, 0 dBm. The constant output power laser diode is used in combination with an optical attenuator to provide the adjustable output power that is needed. The type of optical attenuator can be either fixed or variable attenuation. The fixed attenuation type is neither field adjustable nor remotely controllable. The variable attenuation type is large and expensive and can require additional power sensing circuitry.
SUMMARY OF THE INVENTION
[0003] There is a need for an approach to controlling the output power of laser diodes that is less costly and less bulky than those that require external optical attenuators. There is also a need for a power control mechanism that takes into account the relationship between temperature and wavelength in the operation of laser diodes.
[0004] An apparatus and method of the present approach provides for electrical control of the laser output power without the need for a costly and bulky optical attenuator. The present approach further provides wavelength control to compensate for the relationship between laser diode operating temperature and wavelength.
[0005] Accordingly, a control circuit for a laser diode includes a power controller and a wavelength controller. The power controller adjusts a bias current to the laser diode to change the power output of the laser diode. The power change can have a corresponding wavelength shift effect on the nominal operating wavelength of the laser diode. The wavelength controller compensates for the wavelength shift such that the laser diode maintains operation at the nominal wavelength.
[0006] In an embodiment, the power controller includes a bias current source that provides an adjustable bias current to the laser diode. A power monitor loop includes a backfacet diode for monitoring the laser diode power output to provide a power monitor signal. A power control signal added to the power monitor signal provides a power adjust signal. The bias current source adjusts the bias current responsive to a difference between a power reference voltage input of the bias current source and the power adjust signal.
[0007] In an embodiment, the wavelength controller includes a temperature control circuit that provides a control current to a thermoelectric element for controlling the temperature operation point of the laser diode. A temperature monitor loop includes a temperature sensor for monitoring the temperature operation point to provide a temperature monitor signal. A wavelength compensation signal added to the temperature monitor signal provides a wavelength control signal. The temperature control circuit adjusts the control current to the thermoelectric element responsive to a difference between a temperature reference signal and the wavelength control signal.
[0008] The wavelength compensation signal may be proportional to the power control signal.
[0009] In an alternate embodiment, the wavelength controller includes an etalon element for wavelength compensation.
[0010] In one aspect of the invention, a control circuit includes a power controller for adjusting a bias current to a laser diode to change the power output of the laser diode, the change in power having a corresponding wavelength shift effect on the nominal operating wavelength of the laser diode and a monitoring circuit for sensing the bias current to the laser diode and for generating an output signal in response to the sensed bias current. The control circuit further includes a wavelength controller which receives the output signal from the monitoring circuit and in response to the output signal compensates for the wavelength shift such that the laser diode maintains operation at the nominal wavelength.
[0011] Embodiments of this aspect of the invention may include one or more of the following features. The monitoring circuit includes a sensing resistor. The power controller includes a bias current source that provides an adjustable bias current to the laser diode and has a power reference voltage input. The power controller also includes a power monitor loop having a backfacet diode for monitoring the laser diode power output to provide a power monitor signal, and a power control signal added to the power monitor signal to provide a power adjust signal. The bias current source adjusts the bias current responsive to a difference between the power reference voltage input and the power adjust signal.
[0012] The wavelength controller includes a temperature control circuit that provides a control current to a thermoelectric element for controlling the temperature operation point of the laser diode and having a temperature reference voltage input and a temperature monitor loop including a temperature sensor for monitoring the temperature operation point to provide a temperature monitor signal a wavelength compensation signal added to the temperature monitor signal to provide a wavelength control signal. The temperature control circuit adjusts the control current to the thermoelectric element responsive to a difference between the temperature reference voltage input and the wavelength control signal. The wavelength compensation signal is proportional to the sensed bias current.
[0013] The control circuit can further include the laser diode and a modulator for modulating the output of the laser diode.
[0014] In another aspect of the invention, a method of controlling a laser diode includes the following. A bias current to the laser diode is adjusted to change the power output of the laser diode, the power change having a corresponding wavelength shift effect on the nominal operating wavelength of the laser diode. The level of bias current to the diode is sensed. In response to the sensed level of bias current, compensating for the wavelength shift such that the laser diode maintains operation at the nominal wavelength.
[0015] Embodiments of this aspect of the invention may include one or more of the following steps. Adjusting the change of power output includes monitoring the laser diode power output to provide a power monitor signal, adding a power control signal to the power monitor signal to provide a power adjust signal, and adjusting the bias current responsive to a difference between a power reference voltage signal and the power adjust signal.
[0016] Compensating for the wavelength shift includes providing a control current to a thermoelectric element for controlling the temperature operation point of the laser diode, monitoring the temperature operation point to provide a temperature monitor signal, adding a wavelength compensation signal to the temperature monitor signal to provide a wavelength control signal, and adjusting the control current to the thermoelectric element responsive to a difference between a temperature reference signal and the wavelength control signal.
[0017] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
[0019] [0019]FIG. 1 is a circuit diagram of a laser transmitter of the prior art.
[0020] [0020]FIG. 2 is a chart that illustrates power control characteristics of the transmitter of FIG. 1.
[0021] [0021]FIG. 3 is a chart that illustrates temperature control characteristics of the transmitter of FIG. 1.
[0022] [0022]FIG. 4 is a circuit diagram of laser transmitter.
[0023] [0023]FIG. 5 is a chart illustrating power and wavelength control characteristics of the transmitter of FIG. 4.
[0024] [0024]FIG. 6 is a circuit diagram of another embodiment of a laser transmitter in accordance with the present system.
[0025] [0025]FIG. 7 is a circuit diagram of still another embodiment of a laser transmitter.
DETAILED DESCRIPTION
[0026] A typical laser transmitter 10 of the prior art is shown in FIG. 1. The laser transmitter includes a laser module 18 coupled to a variable optical attenuator (VOA) 30 via an optical fiber 32 . The laser module includes a laser diode 20 , a backfacet diode 22 and a modulator 24 . The laser diode 20 typically provides a continuous wave output at a constant bias level corresponding to a constant power level. A data stream input 11 is coupled through gate 16 to modulator 24 to modulate the continuous wave output of the laser diode 20 . For simplicity the modulator 24 is shown as a diode, though it is understood that it is commonly a Mach-Zhender interferometer or lithium niobate waveguide device. The modulated optical signal is coupled to the optical fiber 32 .
[0027] The constant power output of the laser diode 20 is controlled using a bias current source and a power monitor loop. The bias current source, which includes operational amplifier 12 and transistor 14 , provides an adjustable bias current IDFB to the laser diode. The power monitor loop includes backfacet diode 22 for monitoring the laser diode power output to provide a power monitor signal that is coupled to the negative input of operational amplifier 12 . The output of operational amplifier 12 is coupled to the negative input through capacitor C 1 . The positive input of operational amplifier 12 has a power reference voltage VREF. The operational amplifier 12 adjusts the bias current IDFB responsive to a difference between the power reference VREF and the power monitor signal. For example, if the power monitor signal is less than the power reference VREF, operational amplifier 12 provides more bias current.
[0028] To control the operating temperature of the laser transmitter, the laser module 18 includes a thermistor 26 and a thermal electric cooler (TEC) element 28 . Operational amplifier 34 and transimpedance bridge 36 provide a control current ITEC to the TEC element 28 . A temperature monitor loop includes thermistor 26 for monitoring the temperature operation point to provide a temperature monitor signal that is coupled to the negative input of operational amplifier 34 . The output of operational amplifier 34 is coupled to the negative input through capacitor C 2 . The positive input of operational amplifier 34 has a temperature reference voltage VTEMP. The operational amplifier 34 adjusts the control current ITEC to the TEC element 28 responsive to a difference between the temperature reference VTEMP and the temperature monitor signal. For example, if the temperature monitor signal is less than VTEMP, the operational amplifier 34 provides more current to the TEC element.
[0029] Direct electrical control of the power output of a laser diode generally is understood to be problematic, given the relationship between operating temperature and wavelength in such devices. In particular, the relationship depends on output power and the characteristics of individual devices.
[0030] Referring to FIG. 2, the chart illustrates the effect on operating wavelength when the laser output power is adjusted for the exemplary laser transmitter 10 of FIG. 1. In particular, by applying a voltage VPOWER through a resistor to negative input 40 of operational amplifier 12 , the laser output power is adjusted. Note that the temperature control portion of the laser transmitter is kept constant, i.e., VTEMP is constant. The slope of the power adjustment curve (right vertical axis) is negative. That is, an increase in voltage VPOWER results in a decrease in laser output power. A corresponding change Δλ in operating wavelength occurs (left vertical axis) such that a decrease in laser power output results in a shorter operating wavelength.
[0031] As shown, a power change from 3.0 mW to below 1.0 mW results in a wavelength shift of about 2000 picometers. In modem dense wavelength division multiplex (DWDM) systems designed for 100 GHz or tighter channel spacings, the channels are only +/−100 picometers wide around a nominal specified center wavelength. Thus, the change in wavelength operation that occurs with the power adjustment shown in FIG. 2 is too large and is unacceptable for modem telecommunication systems.
[0032] [0032]FIG. 3 is a chart that illustrates the effect on operating wavelength when the temperature reference voltage VTEMP is adjusted for the laser transmitter 10 of FIG. 1 while the output power of the laser transmitter and VREF are kept constant. The slope of the curve in FIG. 3 is negative. That is, an increase in temperature reference voltage VTEMP causes the TEC element to operate at a cooler temperature, which results in a shorter operating wavelength for the laser diode. As shown, a change in VTEMP from 2 to 3 volts results in a wavelength shift of about 2000 picometers.
[0033] It has been found in the present approach that, by taking into account the wavelength shift due to power adjustment and due to temperature, a power control circuit can be implemented that provides variable laser power output while maintaining operation of the laser diode at a nominal wavelength within an acceptable range.
[0034] In an embodiment of a laser control circuit 100 in accordance with the present approach shown in FIG. 4, a power control signal VMOD is provided that is added to the power monitor signal through resistor network R 1 and R 2 at the negative input of operational amplifier 12 so that the operational power level can be increased or decreased over the nominal set point provided by reference voltage VREF. In addition, to compensate for the wavelength shift of the laser diode 22 , a scaled version 29 of the power control signal VMOD is provided that is added to the temperature monitor signal 27 through resistor R 4 at the negative input of operational amplifier 34 . Note that the control circuit 100 eliminates the need for a VOA (FIG. 1). Thus, a simple but elegant solution is provided to solve the problems noted above.
[0035] Different laser diode devices can exhibit different temperature and wavelength characteristics. Thus, in the control circuit 100 of FIG. 4, the values for resistors R 1 , R 2 , R 3 and R 4 can be accordingly adjusted to fit the characteristics of each laser diode.
[0036] As described, the control circuit 100 provides an adjustable output power. FIG. 5 shows the laser output power (right vertical axis) as it varies with the applied adjustment voltage, VMOD. Note that for VMOD of 0V the output power is approximately 2.5 mW. With VMOD of 3V the output power is approximately 1.5 mW. Thus, linear adjustment of output power is provided.
[0037] [0037]FIG. 5 also shows a residual amount of wavelength variation (left vertical axis) for the control circuit of FIG. 4. Note that for VMOD of 0 V the difference between the intended wavelength and the actual wavelength, given as Δλ, is about 25 picometers. The negative sign indicates that the wavelength is less then the intended wavelength. For VMOD of 4.5 V the difference Δλ is about 0.
[0038] As noted above, DWDM system today require tight channel spacings. Without the wavelength control feature provided as shown in FIG. 4, the variation of the laser wavelength as the power is adjusted from 2.5 mW to 0 mW (FIG. 5) will be very much larger than the acceptable variation. With the control circuit of FIG. 4, the residual wavelength variation is well within the acceptable variation.
[0039] Referring to FIG. 6, a second embodiment of a control circuit 200 is shown. In this embodiment, a Fabry-Perot etalon locker device 42 is used to provide the wavelength compensation. The etalon locker 42 receives light emitted from laser diode 20 , and based upon the wavelength of the light received, outputs a signal to add to the negative input of operational amplifier 34 for controlling the wavelength.
[0040] Other embodiments for providing wavelength compensation when the output power of a laser diode is varied are within the scope of the claims. For example, in the embodiment described above in conjunction with FIG. 4, the value of resistor R 4 was selected to provide the appropriate level of wavelength compensation as the output power of the laser diode is varied. However, in that embodiment, as the laser diode “ages,” the bias current needed to provide a given level of output power will no longer be the same, but will increase. The value of resistor R 4 may no longer be appropriate for providing the proper level of wavelength compensation.
[0041] However, referring to FIG. 7, a laser diode module 300 provides accurate wavelength compensation even as the characteristics of the laser diode changes. In particular, laser diode module provides for wavelength compensation in response to the change in bias current applied to a laser diode 302 . Laser diode module 300 includes many of the same components as the laser circuit shown in FIG. 4. For example, the output power of laser diode 302 is controlled using a bias current source and a power monitor loop. The bias current source includes an operational amplifier 304 and a transistor 306 , which together provide an adjustable bias current I DFB to laser diode 302 . The power monitor loop includes a backfacet diode 308 for monitoring the output power to laser diode 302 and to provide a power monitor signal that is coupled to the negative input of operational amplifier 304 . The output of operational amplifier 304 is coupled to the negative input through capacitor Cl. The positive input of operational amplifier 304 has a power reference voltage VREF. The operational amplifier 304 adjusts the bias current I DFB responsive to a difference between the power reference VREF and the power monitor signal. For example, if the power monitor signal is less than the power reference VREF, operational amplifier 304 increases the level of bias current.
[0042] As was the case in the embodiment of FIG. 4, laser diode module 300 includes a temperature monitor loop for monitoring the temperature operation point to provide a temperature monitor signal that is coupled to the negative input of an operational amplifier 314 . The temperature monitor loop has a thermistor 310 and a thermal electric cooler (TEC) element 312 . Operational amplifier 314 and transimpedance bridge 316 provide a control current ITEC to the TEC element 312 . The output of operational amplifier 314 is coupled to its negative input through a capacitor C 2 . The positive input of operational amplifier 314 has a temperature reference voltage V TEMP . The operational amplifier 314 adjusts the control current I TEC to the TEC element 312 responsive to a difference between the temperature reference V TEMP and the temperature monitor signal. For example, if the temperature monitor signal is less than V TEMP , the operational amplifier 314 provides more current to the TEC element. A power control signal V MOD is added to the power monitor signal through a resistor network R 1 and R 2 at the negative input of operational amplifier 314 so that the operational power level can be increased or decreased over the nominal set point provided by reference voltage V REF . Unlike the embodiment of FIG. 4, however, a scaled version of the power control signal V MOD is not used to compensate for the wavelength shift. Rather, laser module 300 includes a sensing circuit 320 having, in this embodiment, a sensing resistor 322 . An output signal of the sensing circuit 320 is provided via signal line 316 to the negative terminal of operational amplifier 314 . The output signal from sensing circuit 320 provides a connection between that portion of the laser module associated with automatic power control and that portion of the laser module associate with wavelength compensation.
[0043] Thus, the embodiment shown in FIG. 7 is particularly advantageous in applications where the laser module is to be used for extended periods of time. Rather than being proportional to the output power of the laser diode, the wavelength compensation is proportional the bias current.
[0044] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
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A control circuit includes a power controller for adjusting a bias current to a laser diode to change the power output of the laser diode, the change in power having a corresponding wavelength shift effect on the nominal operating wavelength of the laser diode and a monitoring circuit for sensing the bias current to the laser diode and for generating an output signal in response to the sensed bias current. The control circuit further includes a wavelength controller which receives the output signal from the monitoring circuit and in response to the output signal compensates for the wavelength shift such that the laser diode maintains operation at the nominal wavelength.
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[0001] The present invention is directed to a process for the preparation of the mesylate trihydrate of the compound of formula (I), (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol:
[0002] The present invention is further directed to a process for the preparation of the (2S)-(+)-enantiomer of formula (II):
[0003] wherein R 1 is a protecting group selected from the group consisting of benzyl, (C 1 -C 6 )alkylbenzyl, (C 1 -C 6 )alkoxylbenzyl, tri(C 1 -C 6 )alkylsilyl, acyl (e.g., acetyl) and aroyl (e.g., benzoate). In addition, the present invention relates to intermediates useful in said processes.
[0004] The compound of formula (I), (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol, exhibits potent activity as an NMDA (N-methyl-D-aspartic acid) receptor antagonist and is useful in the treatment of epilepsy, anxiety, cerebral ischemia, muscular spasms, multi-infarct dementia, traumatic brain injury, pain, AIDS-related dementia, hypoglycemia, migraine, amyotrophic lateral sclerosis, drug and alcohol addiction, drug and alcohol withdrawal symptoms, psychotic conditions, urinary incontinence and degenerative CNS (central nervous system) disorders such as stroke, Alzheimer's disease, Parkinson's disease and Huntington's disease.
[0005] The mesylate trihydrate form of (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol is superior to the anhydrous mesylate as an active therapeutic agent because of its properties. The mesylate trihydrate has a more stable crystalline form than the anhydrous mesylate salt, and hence, a substantially longer shelf life. The trihydrate is also less subject to breakdown in crystal structure due to the inclusion of water in the crystal. U.S. Pat. No. 6,008,233 describes the mesylate salt trihydrate, the anhydrous mesylate salt and free base of (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol, and methods for their preparation.
[0006] Further, the free base of formula (I), its anhydrous mesylate, and methods of preparing them are also referred to, generically, in U.S. Pat. No. 5,185,343, which issued on Feb. 9, 1993. Their use in treating certain of the above disorders are referred to, specifically, in U.S. Pat. No. 5,272,160, which issued on Dec. 21, 1993; and International Patent Application PCT/IB95/00380, which designates the United States, filed on May 18, 1995 and published as WO96/06081. Their use in combination with a compound capable of enhancing and thus restoring the balance of excitatory feedback from the ventral lateral nucleus of the thalamus into the cortex to treat Parkinson's disease is referred to in International Patent Application PCT/IB95/00398, which designates the United States, filed on May 26, 1995 and published as WO96/37226. The foregoing U.S. patents and patent applications are incorporated herein by reference in their entireties.
[0007] Previous methods for the preparation of the (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol proceeded via racemic synthetic pathways with resolution of the active optical isomers in the steps prior to therapeutic salt formation. One of the problems associated with resolution of compounds relatively late in a synthetic scheme is the waste and reduced efficiency involved in disposing of significant amounts of inactive or less active enantiomers and diastereomers. To maximize the efficacy of the synthesis, it is desirable to have a synthesis which introduces centers of optical activity into the target molecule precursors early in the synthesis. Accordingly, a method for transforming a racemic starting material into an optically active building block for the directed chiral synthetic pathway to a compound of formula (I) would be a significant advantage.
[0008] Although methods for the asymmetric transformation of racemic materials to chiral ones have been reported, the ability to obtain successfully optically active products has often been strictly limited to the specific circumstances and compounds involved. The preparation of optically active α-aminopropiophenones has been achieved by asymmetric transformation. Takamatsu, J. Pharm. Soc. Japan, 76(11), 1219-1222 (1956). In addition, the transformation of racemic 3-(RS)-amino-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one to its nearly optically pure (S)-enantiomer by crystallization induced asymmetric transformation has been reported. Reider et al., J. Org. Chem., 52, 955-957 (1987).
SUMMARY OF THE INVENTION
[0009] The present invention relates to a process for the preparation of the methanesulfonate trihydrate salt of (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol:
[0010] comprising the steps of
[0011] (i) reducing the carbonyl group of a compound of formula (II)
[0012] wherein R 1 is a protecting group, selected from the group consisting of benzyl, (C 1 -C 6 )alkylbenzyl, (C 1 -C 6 )alkoxylbenzyl, tri(C 1 -C 6 )alkylsilyl, acyl (e.g., acetyl) and aroyl (e.g., benzoate), via reaction with a alkali metal borohydride; and
[0013] (ii) cleaving off the protecting group R 1 of a compound of formula (III)
[0014] in the presence of methanesulfonic acid.
[0015] A preferred embodiment of the invention is where the protecting group R 1 is benzyl, (C 1 -C 6 )alkylbenzyl or (C 1 -C 6 )alkoxylbenzyl. Another preferred embodiment is wherein the alkali metal borohydride is lithium borohydride or sodium borohydride. A more preferred embodiment of the invention is wherein the R 1 group is benzyl and the alkali metal borohydride is lithium borohydride.
[0016] Another preferred embodiment is wherein the protecting group R 1 is benzyl and the cleavage of the protecting group of step (ii) is hydrogenolysis conducted in the presence of hydrogen gas and 5%-20% palladium on carbon. A more preferred embodiment is wherein the R 1 group is benzyl and the hydrogenolysis is conducted in the presence of hydrogen gas and 5% palladium on carbon. A preferred embodiment of the invention is wherein steps (i) and (ii) are conducted in a (C 1 -C 6 ) alkanol solvent, optionally admixed with water. A more preferred embodiment of the invention is wherein the solvent used in steps (i) and (ii) is ethanol admixed with water.
[0017] The invention is also directed to a process for the preparation a compound of formula
[0018] comprising the steps of
[0019] (i) placing a compound of formula (IV):
[0020] together with a diaroyl D-tartrate;
[0021] (ii) treating the D-tartrate salt product of step (i) with a weak base.
[0022] A “weak base,” as referred to herein, is a basic compound which is not sufficient in basicity to remove readily the α-proton from a compound of formula (IV). A preferred embodiment of the invention is wherein the diaroyl D-tartrate is dibenzoyl D-tartrate or di-p-toluoyl D-tartrate. A preferred embodiment of the invention is wherein the steps of this process are conducted in a lower alkyl ketonic solvent, more preferably acetone. The more preferred embodiment of the invention is wherein the steps of this process are conducted in acetone at a temperature between 25° C. and the reflux temperature, most preferably between 48 and 52° C.
[0023] A preferred embodiment of the invention is wherein the weak base is a tri(C 1 -C 6 )alkylamine or an alkali/alkaline-earth metal carbonate, bicarbonate or alkylcarboxylate, e.g., NaHCO 3 , Na 2 CO 3 , NaOOCCH 3 , etc. A more preferred embodiment of the invention is wherein the weak base is NaHCO 3 in water admixed with an organic solvent, such as ethyl acetate or methylene chloride, more preferably, ethyl acetate.
[0024] The present invention is also directed to the (2S)-(+)-enantiomer of formula (II):
[0025] or a salt thereof, wherein R 1 is hydrogen or a protecting group selected from the group consisting of benzyl, (C 1 -C 6 )alkylbenzyl, (C 1 -C 6 )alkoxylbenzyl, tri(C 1 -C 6 )alkylsilyl, acyl (e.g., acetyl) and aroyl (e.g., benzoate), and the salt is a diaroyl D-tartrate. A preferred embodiment of the invention is wherein R 1 is benzyl. Another preferred embodiment of the invention is wherein the diaroyl salt is dibenzoyl D-tartrate salt or di-p-toluoyl D-tartrate.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The mesylate salt trihydrate of (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol is a white crystalline solid which has a single crystalline form and good solubility in water (25 and 15 mg/mL in pH 3 and 7 aqueous buffered solutions, respectively). The mesylate salt trihydrate is known to form upon allowing the anhydrous mesylate salt to equilibrate in an 81% relative humidity environment. Previous preparations of the mesylate salt trihydrate required the resolution of the racemate of threo-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol prior to the formation of the mesylate salt trihydrate. This procedure required the disposal of the less active/inactive (1R,2R) isomer after separation.
[0027] The present invention, however, permits the preparation of the mesylate salt trihydrate of a compound of formula (I) by introducing the chiral center at the 2-position of the propanol chain of the final product into the synthetic procedure at an earlier point than previously used in the synthesis of the mesylate trihydrate compound. This early introduction of a chiral center results in a more efficient and higher yielding preparation of the mesylate trihydrate compound without significant formation of enantiomeric and diastereomeric impurities.
[0028] The following reaction Scheme illustrates the process of the present invention. The definition of R 1 is as above, unless otherwise indicated.
[0029] Referring to Scheme 1, the protected racemic compound of formula (IV) is transformed via crystallization-induced asymmetric transformation into the diaroyl D-tartrate salt of the (2S)-compound of formula (VA), wherein aroyl is benzoyl or p-toluoyl. The acidity of the α-proton allows the chiral center to racemize and set up an equilibrium between the (2S)-compound and its (2R)-antipode, as shown in Scheme 2 below. As seen in Scheme 2, in the presence of diaroyl D-tartaric acid, the crystalline diaroyl D-tartrate salt of the (2S)-(+)-compound of formula (VA) is removed from the steady state due to its relative insolubility, driving the equilibrium with the (2R)-(−)-antipode being eventually transformed to the desired (2S)-(+)-form.
[0030] This crystallization induced asymmetric transformation is best achieved in solvents, such as lower alkyl ketonic solvents, e.g., acetone. Optimally, this step is conducted by heating a solution of the compound of formula (IV) and dibenzoyl D-tartaric acid in acetone under an inert atmosphere for approximately 6-7 hours at 48 to 52° C., then cooling to ambient temperature (20 to 25° C.), granulating the resulting slurry, filtering and then drying the obtained salt.
[0031] Referring back to Scheme 1, the diaroyl D-tartrate salt of the (2S)-enantiomer of formula (VA) is then treated with a base, preferably aqueous sodium bicarbonate, in the presence of ethyl acetate or methylene chloride, preferably ethyl acetate. The organic layer is then separated, then concentrated, then added to cold hexanes, and then granulated to obtain the free base compound of formula (II).
[0032] The compound of formula (II) is then subjected to conditions whereby the carbonyl moiety is reduced without concomitant racemization at the α-position. This can be achieved by exposing the compound of formula (II) to mild reduction conditions, e.g., treatment with an alkali metal borohydride, such as lithium borohydride or sodium borohydride, preferably lithium borohydride, in a solvent such as, tetrahydrofuran or ethanol, preferably ethanol. A comparison of the different reduction conditions is shown in Table 1.
TABLE 1 Reduction of the Compound of Formula (II) (wherein R 1 is benzyl) Under Varied Conditions. Reducing Reaction Reaction Mixture Isolated Solids Agent Time Cmpd Cmpd (Mol. Equiv) Solvent (hrs) Temp (III)* E D (III)* E D LiBH 4 (1.6) (a) 19.5 21-22° C. 84.1% — 15.9% 79% 0.1% 0.5% LiBH 4 (1.6) (a) 21 20-21° C. 78.9% 1.7% 19.4% — — — NaBH 4 (1.6) (a) 52 20-22° C. 81.7% 0.4% 14.6% 79% 0.3% 4.2% LiBH 4 (0.8) (a) 32 20-23° C. 86% 1.0% 13.1% 84% 1.5% 3.0% NaBH 4 (0.8) (a) 42 20-22° C. 85% 0.6% 13.5% 83% 0% 5.3% KBH 4 (0.8) (a) 48 20-22° C. 88% Starting Material Unreacted Ca(BH 4 ) 2 (0.8) (a) 48 20-22° C. 90% Starting Material Unreacted K Selectride (b) 1 0.5° C. — — — 46% 34% — (1.1)
[0033] The protecting group R 1 of the product compound of formula (III) is then best removed by hydrogenolysis if that protecting group is benzyl, (C 1 -C 6 )alkylbenzyl or (C 1 -C 6 )alkoxylbenzyl. When the protecting group R 1 is tri(C 1 -C6)alkylsilyl, acyl (e.g., acetyl) or aroyl (e.g., benzoate), it may be removed via conventional techniques known to those in the chemical arts, i.e., treatment with fluoride ion for the silyl group removal or hydrolysis techniques for the acyl/aroyl ester cleavage.
[0034] When R 1 is benzyl, this protecting group is effectively removed by the use of hydrogen gas with a 5-20% palladium on carbon, in an appropriate solvent, such as tetrahydrofuran, to obtain the free base. However, the hydrogenolysis reaction may be conducted with or without the presence of methanesulfonic acid, depending on whether the desired product is the free base or the mesylate salt. When conducted in the presence of methanesulfonic acid, the hydrogenolysis reaction is conducted in a (C 1 -C 6 ) alkanol, optionally in admixture with water, preferably ethanol in admixture with water, the mesylate salt is formed in situ. When the reaction mixture is worked up, water may be also be added to the concentrated filtrate of the hydrogenolysis reaction mixture, then filtered, to yield the mesylate trihydrate salt of the compound of formula (I) as the final product. If low-pyrogen or pyrogen-free conditions are employed, the isolated mesylate salt trihydrate is suitable for use in parenteral applications.
[0035] If the removal of the protecting group by hydrogenolysis is not performed in the presence of mesylate trihydrate, the reaction may be conducted in a less polar solvent, e.g., tetrahydrofuran, to achieve the free base compound. A separate reaction step to make the mesylate salt trihydrate may, of course, be conducted starting from the free base, if so desired.
[0036] The mesylate salt trihydrate, similar to the anhydrous mesylate and free base, possesses selective neuroprotective activity, based upon its antiischemic activity and ability to block, excitory amino acid receptors. The preferred procedure for evaluating the neuroprotective activity of this compound is that described by Ismail A. Shalaby, et al., J. Pharm. Exper. Ther., 260, 925 (1992). This article is incorporated herein by reference in its entirety and described below.
[0037] Cell culture. Seventeen day fetal rat (CD, Charles River Breeding Laboratories, Inc., Wilmington, Mass.) hippocampal cells are cultured on PRIMARIA culture plates (Falcon Co., Lincoln Park, N.J.) for 2 to 3 weeks in serum containing culture medium (minimum essential medium with nonessential amino acids, containing 2 mM glutamine, 21 mM glucose, penicillin/streptomycin (5000 U each), 10% fetal bovine serum (days 1-7) and 10% horse serum (days 1-21). Cells are either plated on 96-well microtiter plates at a density of 80,000 cells per well or on 24-well culture plates at a density of 250,000 cells per well. Cultures are grown at 37° C. in a humidified CO 2 tissue culture incubator containing 5% CO 2 /95% air. Proliferation of nonneuronal cells is controlled by adding 20 μM uridine and 20 μM 5-fluoro-2-deoxyuridine (Sigma Chemical Co., St. Louis, Mo.) from days 6 to 8 of culture. Culture media is exchanged every 2 to 3 days with fresh stock.
[0038] Glutamate toxicity. The cultures are assessed for glutamate toxicity 2 to 3 weeks from initial plating. Culture media is removed and cultures rinsed twice with a CSS (in millimolar.): NaCl, 12-; KCl, 5.4; MgCl 2 , 0.8; CaCl 2 , 1.8; glucose, 15; and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, 25 mM (pH 7.4). Cultures are then exposed for 15 minutes (37° C.) to various concentrations of glutamate. After this incubation, cultures are rinsed 3 times with glutamate-free CSS and twice with fresh culture medium without serum. The cultures are then incubated for 20 to 24 hours in serum-free culture medium. The compound being tested is added 2 minutes before and during the 15-minute exposure to glutamate. In some experiments, the compound is added at different times after the glutamate exposure and for the following 20 to 24 hours.
[0039] Cell viability is routinely assessed 20 to 24 hours after the excitotoxin exposure by measuring the activity of the cytosolic enzyme LDH. LDH activity is determined from the culture medium of each of the 96 wells of the microtiter plates. A 50-μl sample of the media is added to an equal volume of sodium-phosphate buffer (0.1 M, pH 7.4) containing 1.32 mM sodium pyruvate and 2.9 mM NADH. The 340 nm absorbance of the total reaction mixture for each of the 96 wells is monitored every 5 seconds for 2 minutes by an automated spectrophotometric microtiter plate reader (Molecular Devices; Menlo Park, Calif.). The rate of absorbance is automatically calculated using an IBM SOFTmax program (version 1.01; Molecular Devices) and is used as the index of LDH activity.
[0040] Morphological assessment of neuronal viability is determined using phrase contrast microscopy. The 96-well culture plates do not permit good phase-contrast imagery, so cells cultured on 24-well plates are used for this purpose. Quantitatively, both culture platings are equally sensitive to glutamate toxicity, and display 2- to 3-fold increases in LDH activity 24 hours after exposure to 0.1 to 1.0 mM glutamate.
[0041] Reagents. DTG can be purchased from Aldrich Chemical Company (Milwaukee, Wis.), and haloperidol from Research Biochemicals Inc. (Natick, Mass.). Spermine can be purchased from Sigma Chemical Co. (St. Louis, Mo.). Horse and fetal bovine serum can be purchased from Hyclone (Logan, Utah). Culture medium, glutamine and penicillin/streptomycin can be purchased from Gibco Co. (Grand Island, N.Y.).
[0042] Data analysis. Neurotoxicity can be quantified by measuring the activity of LDH present in the culture medium 20 to 24 hours after glutamate exposure. The increased LDH activity in the culture media correlates with destruction and degeneration of neurons (Koh and Choi, 1987). Because actual levels of LDH vary from different cultures, data are routinely expressed relative to buffer-treated sister wells of the same culture plate. To obtain an index of LDH activity from glutamate and drug-treated cultures, the LDH values from control cultures are subtracted from that of the treatment groups. Data for drug treatments is expressed as a percentage of the increase in LDH induced by 1 mM glutamate (or NMDA) for each experiment. Concentrations of NMDA antagonists required to reverse 50% of the LDH increase induced by excitotoxins (IC 50 ) are calculated using log-probit analysis from the pooled results of three independent experiments.
[0043] The selective neuroprotective antiischemic and excitatory amino acid blocking activities of the mesylate salt trihydrate of this invention render it useful in the treatment of disorders selected from degenerative CNS disorders such as stroke, Alzheimer's disease, Parkinson's disease and Huntington's disease; epilepsy, anxiety, cerebral ischemia, muscular spasms, multiinfarct dementia, traumatic brain injury, pain, AIDS related dementia, hypoglycemia, migraine, amyotrophic lateral sclerosis, drug and alcohol addiction, drug and alcohol withdrawal symptoms, psychotic conditions and urinary incontinence.
[0044] In the systemic treatment of such disorders, the dosage is typically from about 0.02 to 250 mg per kg per day (0.001-12.5 g per day in a typical human weighing 50 kg) in single or divided doses, regardless of the route of administration. A more preferred dosage range is from about 0.15 mg per kg per day to about 250 mg per kg per day. Of course, depending upon the exact nature of the illness and the condition of the patient, doses outside this range may be prescribed by the attending physician. The oral route of administration is generally preferred. However, if the patient is unable to swallow, or oral absorption is otherwise impaired, the preferred route of administration will be parenteral (i.m., i.v.) or topical.
[0045] The mesylate salt trihydrate may be administered in the form of pharmaceutical compositions together with a pharmaceutically acceptable vehicle or diluent. Such compositions are generally formulated in a conventional manner utilizing solid or liquid vehicles or diluents as appropriate to the mode of desired administration: for oral administration, in the form of tablets, hard or soft gelatin capsules, suspensions, granules, powders and the like; for parenteral administration, in the form of injectable solutions or suspensions, and the like; and for topical administration, in the form of solutions, lotions, ointments, salves and the like.
[0046] The following Examples illustrate the processes of the present invention and the preparation of the compounds of the invention. Melting points are uncorrected. NMR data are reported in parts per million (δ) and are referenced to the deuterium lock signal from the sample solvent (deuterochloroform, unless otherwise specified). Commercial reagents were utilized without further purification.
EXAMPLE 1
(2S)-1-(4-Benzyloxyphenyl)-2-(4-hydroxy4-phenylpiperidin-1-yl)-1-propanone dibenzoyl-D-Tartrate Salt
[0047] Racemic 1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone (100 g, 0.24 mol) and dibenzoyl D-tartaric acid (86.3 g, 0.24 mol) were added to acetone (1.5 L) under a nitrogen atmosphere to give a yellowish solution. After the solution was heated for 1 hour at 48 to 52° C., a thick white slurry was formed. The slurry was heated an additional 6.5 hours and then cooled to 20 to 25° C. The solid was granulated for 1 hour at 20 to 25° C., filtered, and then the cake washed with fresh acetone (0.2 L). The white solid was dried in vacuo for 12 to 15 hours at 35 to 40° C. to give 155.6 g of the title compound (84% yield). mp 140.1-141.1° C.; [α] D 25 +65.4 (c 4.5, CH 3 OH). Chiral HPLC showed that the salt contained 0.9% of the (−) enantiomer, (2R)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone.
EXAMPLE 2
(2S)-1-(4-Benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone
[0048] Under a nitrogen atmosphere, (2S)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1- yl)-1-propanone dibenzoyl D-tartrate salt (150.0 g, 0.19 mol) was suspended in ethyl acetate (0.45 L, 3.0 mL/g of tartrate salt) and water (0.75 L, 50 mL/g of tartrate salt) containing NaHCO 3 (51.0 g, 0.61 mol). The mixture was stirred for 2 hours at 20 to 25° C. while CO 2 was liberated (pH f =8.1). Stirring was stopped and the clear layers were allowed to separate. The lower aqueous layer was separated and then the ethyl acetate layer was concentrated to 0.1 L at 25 to 30° C. under reduced pressure. The concentrate was slowly added over 2 hours to hexanes (0.5 L) cooled to 15 to 20° C., The slurry was concentrated to 0.4 L, the solids were granulated for 1 hour at 15 to 20° C., filtered, and then washed with additional hexanes (80 mL). (2S)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone was dried in vacuo for 12 hours at 40 to 45° C. to give 77.8 g of white free base in 96.7% yield. M.p. 102.5-103.8; [α] D 25 +18.9 (c 8.9, CH 3 OH). 1 H NMR (CDCl 3 )δ8.13 (d, J=8.7 Hz, 2H) 7.2-7.4 (m, 10H), 7.00 (d, J=8.7 Hz, 2H), 5.13 (s, 2H), 4.11 (g, J=6.8 Hz, 1H), 2.6-2.9 (m, 4H), 2.0-2.2 (m, 2H), 1.7-1.8 (m, 2H), 1.31 (d, J=6.8 Hz, 3H). 13 C NMR (CDCl 3 )δ199.69, 162.75, 136.47, 131.49, 129.72, 128.96, 128.55, 128.50, 127.77, 127.23, 124.80, 114.58, 71.44, 70.34, 64.78, 47.83, 44.62, 39.14, 38.79, and 12.28. Chiral HPLC showed that the (−) enantiomer, (2R)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone was present at 1.2%.
EXAMPLE 3
(1S,2S)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol
[0049] Over 20 minutes, (2S)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanone (75 g, 0.18 mol) was added to a suspension of lithium borohydride (3.15 g, 0.15 mol) in ethanol (0.75 L) maintained under a nitrogen atmosphere at 20 to 25° C. After stirring for about 5 minutes, a mild exotherm occurred raising the temperature to 27° C. The slurry was stirred for 42 hours at 20 to 25 ° C. when HPLC indicated that the reaction was complete. Water (37.5 mL) was added and the slurry was granulated for 1 hour at 20 to 25° C. The white solid was filtered and then washed with ethanol (75 mL), water (150 mL), and finally ethanol (75 mL). The product was dried in vacuo at 40 to 45° C. for 20 hours to give 65.3 g of the title compound. The (1S,2S) amino alcohol product was obtained in 78.3% yield and contained only 2.3% of diastereomers. M.p. 158-161° C., [(α] D 25 +38.7 (c 6.1, CH 3 OH).
EXAMPLE 4
(1S,2S)-1-(4-Hydroxyphenyl)-2-(4-hydroxy-4-phenvlpiperidino)-1-propanol, Methanesulfonate Salt Trihydrate
[0050] Five percent palladium on carbon catalyst (0.75 g, 50% water-wet), (1S,2S)-1-(4-benzyloxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol (5.0 g, 12.0 mmol), ethanol (62.5 mL), and methanesulfonic acid (1.15 g, 12.0 mmol) were combined in a Parr pressure reactor under a nitrogen atmosphere. The nitrogen atmosphere was exchanged for hydrogen (3×25 psi) and then the hydrogen pressure was increased to 50 to 55 psi. The mixture was heated and stirred at 50 to 55° C. for 5 hours when HPLC indicated that the reaction was complete. The hydrogen gas was slowly vented, the reactor flushed with nitrogen, and then the warm (50° C.) reaction mixture was filtered through Celite. The Celite filter cake was washed with ethanol (5 mL). The combined wash and filtrate were concentrated in vacuo to 10 mL. Water (17.5 mL) was added and the solution was concentrated at atmospheric pressure until a distillate temperature of 76° C. was obtained. The clear solution was slowly cooled over 1 hour to 15 to 20° C. and then cooled further to 0 to 5° C. After granulating for 1 hour at 0 to 5° C., the thick slurry was filtered and the cake washed with cold water (5° C., 2.5 mL). The solid was dried for 18 hours at 20 to 25° C. to give 4.71 g of the title compound for an 83% yield. The product was identical to an authentic sample of the title compound. If low-pyrogen water and pyrogen-free conditions are employed in the above procedure, isolated title compound is suitable for parenteral applications.
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The present invention is directed to a novel process for the preparation of the mesylate trihydrate of the compound of formula (I), (1S,2S)-1-(4-hydroxyphenyl)-2-(4-hydroxy-4-phenylpiperidin-1-yl)-1-propanol:
The present invention is further directed to a process for the preparation of a (2S)-(+)-compound of formula (II):
wherein R 1 is a protecting group. In addition, the present invention relates to intermediates useful in said processes.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to an automotive vehicle and more particularly to an arrangement for mounting the engine on the chassis thereof so that engine vibration induced resonance within the cabin is reduced.
2. Description of the Prior Art
In a known arrangement, a buffer rod has been added to the normal engine mounting arrangement for increasing the stiffness of the engine mounting in an effort to reduce the vibration transmitted to the vehicle body from the engine, which vibration tends to induce annoying noise and/or resonance within the vehicle cabin during frequently used middle engine speed operating conditions. However, this arrangement has failed to be effective in that, to avoid the buffer rod per se from unwantedly resonating during middle and high speed operation, it is necessary to select the vibrational characteristics so that the resonance frequency thereof is above the maximum frequency of the vibration from the engine during high speed operation, which in turn has lead to the phenomenon that the vibrational force transmitted to the vehicle body through the normal engine mounts and through the buffer rod re-enforce each other to actually increase the noise and/or resonance within the vehicle cabin. Accordingly, it has been necessary to increase the mass and the size of the elastomeric members used in the engine mountings, which in turn, makes the disposition of same within a crowded engine compartment difficult and increases the overall weight of the vehicle. Further, this measure has proven to be only partly effective.
SUMMARY OF THE INVENTION
In general terms, the present invention features a buffer rod which provides a dynamic damping effect. The rod has two resonance frequencies, the first of which is slightly lower than the engine vibration frequency whereat resonance noise within the vehicle cabin is apt to begin, while the second is closed to the maximum vibration frequency of the engine. The dynamic damping phenomenon is brought about by a first change in phase of the vibration transmitted by the buffer rod at or about its first resonance frequency, whereby during engine operation which produces low frequency vibration (viz., shaking), the buffer rod functions to increase the rigidity of the engine mounting arrangement as a whole until the engine vibration frequency approaches and/or exceeds the first frequency at which the buffer rod resonates. The rod then functions to reduce the rigidity of the engine mounting arrangement as a whole and induce suitable conditions for preventing the transmission of higher frequency vibrations which produce sound. More specifically, the change in the phase of vibration transmitted through the buffer rod at or about its first resonance frequency causes the vibration transmitted through the engine mounts per se and the vibration transmitted through the buffer rod to combine to offset each other just prior to the frequency at which the vehicle cabin will be subject to resonance noise. This phenomenon is maintained by the effect of the second resonance overlapping the first, and continues until the engine vibration frequency approaches and/or reaches the second resonance frequency when a second phase change occurs. This second phase change increases the rigidity of the engine mounting arrangement as a whole, but occurs above normally experienced frequencies and/or near the maximum engine frequency, so that highly improved engine vibration damping is achieved throughout low, middle and substantially all high speed vehicle operations, notably improving the vehicle cabin environment during same.
It is therefore an object of the present invention to provide a buffer rod which will vary the spring modulus of the engine mounting arrangement as a whole during a selected frequency range, and accordingly reduce the generation of resonance noise in the vehicle cabin without the need of overly large elastomeric insulators in the main engine supporting brackets.
In more specific terms, the present invention is a suspension system for mounting an engine on a chassis comprising: at least one engine mount having an elastomeric insulating member interposed between said engine and said chassis; and means defining a dynamic damper mechanism having first and second resonance frequencies, said dynamic damping mechanisim interconnecting said engine and said chassis for cooperating with said at least one engine mount so that when said engine vibrates with a frequency lower than a first predetermined engine vibration frequency which is substantially equal to said first resonance frequency, the effective spring modulus of said elastomeric insulating member and said dynamic damper mechanism is increased, and upon the engine vibration frequency approaching and/or exceeding said first predetermined engine vibration frequency, the effective spring modulus of said elastomeric insulating member and said dynamic damper mechanism is reduced until the engine vibration frequency approaches and/or reaches a second predetermined engine vibration frequency, which second engine vibration frequency is substantially equal to said second resonance frequency.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will become more clearly appreciated from the following description taken in conjunction with the accompanying drawings in which like reference numerals denote corresponding elements, and in which
FIG. 1 is a front elevational view of a first embodiment of the present invention shown operatively interconnecting an engine and a chassis on which the engine is mounted;
FIG. 2 is a side elevational view of the arrangement shown in FIG. 1;
FIGS. 3 and 4 are respective front and side elevational view of the buffer rod according to the first embodiment of the present invention;
FIG. 5 is a perspective view of a part of the buffer rod shown in FIGS. 1 to 4;
FIGS. 6 and 7 show functional models of the main engine mounting bracket and the buffer rod, respectively;
FIG. 8 shows a functional model of the engine mounting arrangement as a whole, viz., the combination of the main engine mounting bracket and the buffer rod;
FIG. 9 is a graph showing the change in spring modulus of the buffer rod with respect to the frequency of vibration passing therethrough;
FIG. 10 is a graph showing the change in phase of vibration passing through the buffer rod with respect to frequency;
FIG. 11 is a graph showing the change of spring modulus of the engine mounting arrangement as a whole with respect to frequency;
FIGS. 12 and 13 are respective front and side elevational views of a second embodiment of the present invention; and
FIG. 14 is an exploded view of the arrangement shown in FIGS. 12 and 13.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to FIGS. 1 to 5, a first embodiment of the present invention is shown. In these figures, an engine 10 is mounted on a chassis 12 by a plurality of main mounting brackets 14 (only one is shown). The main mounting bracket includes a mounting arm or bracket 16 fixedly secured to the engine 10, an elastomeric insulator 18 and "L" shaped plates 20 disposed on either side of the insulator 18 and interposed between the arm and the chassis.
A buffer rod 22 is connected at one end to the mounting arm 16 and at the other end to the chassis 12. The buffer rod 22 comprises two essentially identical halves 24, 24, one of which is clearly shown in FIG. 5. Each half comprises a bracket 28 having a cylindrical housing member 30 fixed to one end thereof in which a first annular elastomeric insulator 32 is disposed. A cylindrical sleeve 34 is snugly disposed through the annular insulator member 32. A second insulator 38 is fixedly connected by bonding, vulcanizing or the like at one face to the other end of the bracket, and in turn has a plate 40 fixedly connected to an opposite face thereof by a similar technique. This plate carries a threaded shaft 42 thereon which projects essentially at a right angle with respect to the plate. The bracket is also formed with an elongated slot 44 therein for receiving therethrough the threaded shaft of the corresponding half.
The buffer rod is thus formed by inverting the halves and fastening same together as best shown in FIGS. 3 and 4, by applying nuts 46 to each of the threaded shafts. Subsequently, the buffer rod 22 is mounted between the engine and the chassis by connecting bolts 48 and 50, as shown in FIGS. 1 and 2.
FIGS. 6, 7 and 8 show, respectively, functional models of the main engine mounting bracket, the buffer rod and the combination of the buffer rod and the main engine mounting bracket.
In FIG. 6, the spring represents the elastomeric insulator 18. Under the conditions that this spring member is displaced through a distance (x) at a given frequency (f), and given that the damping effect of the elastomeric insulator is ignored, then the force (Fe) exerted at the points of connection to the engine and the chassis can be expressed by the following equation,
Fe=ke·x
where ke is the spring modulus of the elastomeric insulator 18.
In FIG. 7, the masses M 1 and M 2 each represent the combined mass of a bracket 28, a cylindrical housing 30, a plate 40, a threaded shaft 42 and a nut 46. The spring member interconnecting the two masses and having a spring modulus of (k 1 ) represents the two second insulators 38, while the upper and lower springs (spring moduli k 0 and k 2 respectively) each represent an annular insulator 32.
Thus, when the buffer rod is subject to conditions which induce a displacement of (x) at a given frequency (f), the force (Fs) occuring at the points of connection to the engine and the chassis can be expressed by the following equation: ##EQU1## where ω=2πf
FIG. 8 shows a model which represents the engine mounting arrangement as a whole, viz., the combination of the main engine mounting and the buffer rod. As seen in FIG. 9, the spring modulus (Fs/x) of the buffer rod varies with frequency. Further, due to the presence of the two suspended masses M 1 and M 2 , the buffer rod has two resonance points. As shown by the curve in FIG. 9, at the resonance points which respectively occur at (f 1 ) and (f 2 ), the spring modulus of the buffer rod tends to maximize. However, as shown in FIG. 10, at the first resonance point, the vibration passing through the buffer rod undergoes a 180 degree phase change. At the second resonance point the vibration undergoes another 180 degree phase change. The effect of the first phase change is to cause the vibration passing through the main engine mounting bracket and the buffer rod to interfere, with one another and to induce a sudden reduction in the effective spring modulus (Ft/x), "softening", of the engine mounting arrangement as a whole. Prior to the first phase change, the rod and the main engine mounting bracket re-enforce each other, as would normally be expected. Subsequent to the sudden "softening" of the engine mounting arrangement as a whole, the spring modulus tends to slowly increase, however, due to the overlapping effect of the second buffer rod resonance, and the spring modulus as a whole again softens until at the second phase change, the interference between the vibrations ceases and the spring modulus suddenly increases to almost its orignal level.
Using the functional models, it can be shown that where the spring moduli of the annular insulators (k 0 and k 2 ) are equal and the mass M 1 =M 2 , then ##EQU2## where k=k 0 =k 2 and M=M 1 =M 2
Hence, by using the two above equations it is possible to select the masses and spring moduli so that (f 1 ) and (f 2 ) span the frequency range in which resonance noise is apt to occur within the vehicle cabin, particularly when the vehicle is running at high speed.
For example, in the case of a four cylinder engine, if (f 1 ) is selected to fall within the range of 90 to 140 Hz, while (f 2 ) is selected to be greater than 200 Hz, viz., if f 1 =100 Hz (approximately the frequency at which the engine vibrates at 3000 RPM), f 2 =220 Hz (approximately the frequency at which the engine vibrates at 6000 RPM), k=8.06 Kg/mm and k 1 =15.47 Kg./mm, the level of resonance noise between engine speeds of 3000 RPM and 6000 RPM is notably reduced. In addition, by using a buffer rod having the above mass and spring constant characteristics, engine vibration at very low frequencies (viz., 10 Hz) is prevented from being transmitted to the vehicle body.
FIGS. 12 to 14 show a second embodiment of the present invention. In this arrangement, two elastomeric discs 51, 52 are secured to a threaded shaft 54 fixedly connected to a cylindrical housing member 55. Each elastomeric disc is clamped between nuts 56 and washers 58 and thus secured in the illustrated position. An annular elastomeric insulator 60 is disposed within the cylindrical housing member 55, and a cylindrical sleeve 62 is disposed snugly therethrough. Snugly disposed about and enclosing the elastomeric discs 51 and 52, is a cylinder 64 which, in turn, is fixedly connected to a second cylindrical housing 66 which receives a second annular elastomeric insulator 68 and second cylindrical sleeve 70.
With this arrangement, mass M 1 takes the form of the cylinder 64 and cylindrical housing 66 while mass M 2 takes the form of the threaded shaft 54, nuts and washers 56, and 58 plus the cylindrical housing 55. Due to the snug fit of the elastomeric discs 51, 52 in the cylinder 64, the discs grip the inner surface of the cylinder and establish a suitable working connection therebetween and thus define a model such as found in FIG. 7.
The function of this embodiment is essentially the same as the first but with the exceptions that that masses M 1 and M 2 need not be equal and that due to the friction fitting of the discs 51, 52 within the cylinder additional vibration may be absorbed by the sliding of the discs within the cylinder. Further, the slidability of the discs within the cylinder also eliminates the need for a separate device for adjusting the length of the buffer rod when fitted to the vehicle.
Thus in summary, the buffer rod interconnects an engine and a vehicle chassis in addition to the main engine mounts, and has a first resonance frequency slightly lower than the engine vibration frequency at which resonance in the vehicle cabin is apt to begin, and a second near the maximum engine vibration frequency. Upon approaching and/or reaching the first resonance frequency the phase of vibration passing through the rod changes so that instead of increasing the spring modulus of the combination of engine mounts and buffer rod to damp vibrations which would otherwise shake the vehicle, the spring modulus thereof is reduced to a very low value due to the interference between the vibration passing through the mounts and the buffer rod. This sudden softening of the engine suspension as a whole, damps the engine vibration which would otherwise induce resonance in the vehicle cabin. This softening effect is maintained until the engine vibration frequency reaches the second resonance frequency whereupon a second phase change occurs.
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An engine mounting buffer rod is constructed to constitute two suspended masses interconnected by elastomeric means to endow on the rod two resonance frequencies. The resonance frequencies are selected to span the vibrational range in which resonance noise is apt to occur in the vehicle cabin so that a first change in the phase of vibration passing through the buffer rod causes an interference with the vibration passing through the main engine mounting brackets to soften the mounting arrangement as a whole and absorb vibrations which would otherwise induce cabin resonance noise. The effect of the second resonance overlaps the first to prolong the softening effect until the second phase change induced thereby occurs.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority in International Patent Application No. PCT/US2015/025199, filed Apr. 9, 2015, which claims priority in U.S. Provisional Patent Application No. 61/977,556, filed Apr. 9, 2014, both of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to the field of mobile machinery, and specifically to a wireless camera system for mobile operations.
[0004] 2. Description of the Related Art
[0005] The practice of agriculture has been largely the same for many years. Advances in electronic vehicle control and sensors have allowed machines to become more efficient and for the production rate of agricultural crops to be increased dramatically. However, true advances in agriculture are not possible without veering away from these common practices and thinking in a dramatically different way.
[0006] What is needed in the art is a system for performing planting and harvesting functions which is not limited by past equipment limitations.
SUMMARY OF THE INVENTION
[0007] This invention describes a wireless camera system for mobile operations.
[0008] One aspect of the present invention is a wireless camera system for mobile operations, comprising a mobile device, a software application, and at least one camera module, the at least one camera module comprising an image capture device, a memory, and a communications link, wherein the at least one camera module is mounted on or near a vehicle, wherein the software application is executing on the mobile device, wherein images captured by the at least one camera module may be transmitted over the communications link to the mobile device, wherein the software application processes images received from the at least one camera module, and wherein the software application displays the processed images on the screen of the mobile device.
[0009] This aspect and others are achieved by the present invention, which is described in detail in the following specification and accompanying drawings which form a part hereof
BRIEF DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a block diagram of a wireless agricultural camera system.
[0011] FIG. 2 is an illustration of how the user can create graphics as reference marks on camera view as shown on a mobile device.
[0012] FIG. 3 is an alternate illustration of how the user can create graphics as reference marks on camera view as shown on a mobile device.
[0013] FIG. 4 is an illustration of one method for placing wireless cameras on a vehicle to obtain a 360 degree view around the vehicle.
[0014] FIG. 5 shows an illustration of how views from multiple cameras might be merged to obtain a complete 360 degree view.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
I. Introduction, Environment, and Preferred Embodiment
[0015] As required, detailed aspects of the present invention are disclosed herein, however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure.
[0016] Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, down, front, back, right and left refer to the invention as orientated in the view being referred to. The words, “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the aspect being described and designated parts thereof Forwardly and rearwardly are generally in reference to the direction of travel, if appropriate. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning.
II. Preferred Embodiment Wireless Camera System
[0017] With reference now to the drawings, and in particular to FIGS. 1 through 5 thereof, a new wireless camera system for mobile applications will be discussed. FIGS. 1 through 5 relate to a system of wireless cameras which can be used to monitor operations on or around an agricultural vehicle or other mobile application. It should be noted that, although the camera system and examples shown herein relate to a camera system for use on an agricultural vehicle, the same system can be used on any type of system, whether a mobile or stationary system.
[0018] FIG. 1 shows the components of the wireless camera system. A number of wireless cameras 14 (shown in FIG. 1 as A, B, C, and D, but any number of cameras may be present in the system, from one to many) are mounted on various locations on the vehicle. Each camera 14 is placed to show a different area of the vehicle or surrounding environment of interest to the operator. These cameras 14 are self-contained, self-powered units that can be moved and adjusted as needed, and they are capable of transmitting and receiving data over a wireless connection 16 . In an alternate embodiment, the cameras 14 may tie into vehicle power rather than being self-powered units. The cameras 14 may each have a built-in mounting system, which may be a clamp, a magnetic mount, a screw or bolt mount, or any other appropriate time of mounting method or mechanism.
[0019] It should be noted that the term “wireless connection” here is meant to be inclusive of any type of communication technology that does not require a hard-wired connection. This may include Bluetooth, 80211 Wi-Fi, cellular connection, or any other appropriate type of wireless protocol.
[0020] These cameras 14 transmit images to a mobile device 10 such as an iPad or similar device, and their captured video and images (camera views) 12 may be displayed on the screen of the mobile device. The view 12 from each camera 14 may be displayed on a split screen such that two or more of the views 12 are visible at once, or the operator can select a single camera view 12 to display at a given moment. Alternately, two or more camera views 12 may be “stitched together” to form a single seamless image showing more area than any single camera 14 could show independently. This stitching function will be discussed in more detail in the discussion of FIG. 5 below.
[0021] FIG. 2 is a close up view of how a user of the mobile device 10 of the present invention may interact with one or more of the camera views 12 to create reference graphics. FIG. 2 shows the mobile device 10 with alive image 12 of a grain cart 26 or a similar vehicle or application. The operator of a harvester (combine) using the wireless camera system can use the image 12 of the grain cart (in this example) so that they can properly position the unloading auger 24 of the combine properly over the grain cart 26 . If the unloading auger 24 is not positioned properly, grain 28 being unloaded from the combine unloading auger 24 may spill over the side and onto the ground.
[0022] Once the operator finds a position of the combine and unloading auger 24 that works, they can interact with the mobile device view 12 and create a “reticule” or crosshairs graphic 22 that is superimposed over the view 12 . This “reticule” 22 can be remembered by the application running on the mobile device 10 and can be brought up on a subsequent image of the grain cart as a reference point. That is, the reticule 22 can be displayed by the software on the mobile device 10 such that it appears in essentially the same spot on the subsequent image or view 12 , and can be used as a reference for positioning for the operator of the combine during the unloading operation.
[0023] Similarly, as shown in FIG. 3 , the operator can draw lines 30 or other shapes on the display to be used as references points. The example image in FIG. 3 is of the tank of a combine or grain cart 26 . The straight lines 30 shown in FIG. 3 may have been drawn there by a farmer with a lot of experience in how full to fill a grain tank 26 before it needs to be unloaded. So the farmer can operate the mobile device 10 so that it displays the view 12 of the grain tank 26 and then draw slope lines 30 on the view 12 so that an inexperienced operator will know approximately when to stop by unloading the harvested grain until the slopes of the pile of grain 28 approximately matches the slope of the reference lines 30 . These reference lines 30 can be saved for later display on similar views 12 .
[0024] The application running on the mobile device may have intelligent software routines which remember the position of the lines 30 based on the camera angle present when the lines 30 were created, and use this information to reposition the lines 30 for later display with similar views 12 . Obviously, lines 30 drawn on an image as seen from one view angle 12 will look different if you switch to an alternate view angle 12 . The application may have software to compensate for this fact, perhaps searching for key indexing points on the view 12 to line up the reference lines 30 , or perhaps remembering the location in space of the camera at the time the image was taken.
[0025] Another use of the wireless camera system of the present invention is to create a 360-degree view of the environment around the tractor or vehicle. This is shown in FIGS. 4 and 5 .
[0026] FIG. 4 shows an overhead view of a typical tractor 100 with four cameras 14 mounted on the cab roof (or anywhere else on the vehicle 100 , as appropriate). Each camera 14 is covering a different view of the environment around the tractor 100 . More than four cameras 14 , mounted in a circular pattern around the vehicle 100 , could be used to capture additional detail from the environment. The dashed lines 32 in FIG. 4 are provided for reference only, showing the approximate viewing angle of each of the four wireless cameras 14 shown in this embodiment and example.
[0027] The video or images captured from these cameras could then be “stitched together” by the software application running on the mobile device 10 to create a 360-degree view, as shown in FIG. 5 . The example image in FIG. 5 shows an image of a tractor 100 , which may be a graphical representation of the tractor/vehicle 100 pulled from a library of models, or an actual image of a vehicle of the same style. The tractor 100 is superimposed on actual video footage that has been stitched together. That is, the imagery taken from the four cameras 14 can be processed and joined together into a larger image. Dashed lines 40 are shown on the display of the mobile device 10 , showing the dividing lines between the four images. The images from each camera 14 are shown in FIGS. 5 as 34 a, 34 b, 34 c, and 34 d. Assuming the cameras 14 are positioned as shown on the tractor 100 as seen in FIG. 4 , each camera 14 will capture images from one of four directions, and the images may be tweaked to make them fit together into a larger image. Because the images may overlap, an algorithm running on the mobile device 10 could use the overlapping imagery to join the images into a single larger image. The dashed lines 40 may actually be displayed on the mobile device 10 to show which image comes from which camera. The image displayed in this manner will be composed of real images, showing real-world things such as roads 38 and hazards 36 .
[0028] Additional graphics routines may allow the operator to spin the view visible on the mobile device so that he or she can see a panoramic view of the environment, or to see a simulated 3D environment based on the images seen in the images.
[0029] The cameras described in the examples above are shown focused “inwardly”, that is, they show images of the tractor itself However, as these cameras are mobile and self-contained, they can be mounted to see imagery external to the vehicle. For example, a camera could be mounted on the boom of a sprayer, pointed down and slightly ahead of the spray nozzles, to allow the operator to see obstructions or humans or animals in the path of the spray.
[0030] Having described the preferred embodiments, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. The examples and processes defined herein are meant to be illustrative and describe only particular embodiments of the invention.
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A wireless camera system for mobile operations, comprising a mobile device, a software application, and at least one camera module, the at least one camera module comprising an image capture device, a memory, and a communications link, wherein the at least one camera module is mounted on or near a vehicle, wherein the software application is executing on the mobile device, wherein images captured by the at least one camera module may be transmitted over the communications link to the mobile device, wherein the software application processes images received from the at least one camera module, and wherein the software application displays the processed images on the screen of the mobile device.
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PRIORITY
[0001] The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/250,087 to David Cross, titled “Roman Blind Safety Release Mechanism”, the contents of which are incorporated herein by reference.
BACKGROUND
[0002] The present invention relates to a safety release mechanism for Roman Shades or Blinds. Roman Shades or Blinds are a popular choice in window coverings, and each are generally made of fabric in such a way that a unitary piece of fabric is hung vertically in a window opening to block incoming light. In operation, Roman Shades or Blinds are raised or lowered through the use of two or more lift cords that are attached on each side of the bottom of the shade or hem bar, with the lift cord running along the back of the Roman Shades or Blinds and through guide rings or openings in the fabric itself, and up to or through the head rail of the Roman Shades or Blinds.
[0003] As noted above, the cords are attached at or near the bottom of the shade or hem bar, and are guided through the rings or cord guides to the top of the Roman Shade head rail and back through a pulley system or catch system such that when the cord is pulled by a user, the attachment point on the cord guides is pulled upward, thereby allowing the shade to be raised from the bottom up. As the lift cords are urged upward through pulling on the pull cord or operating the clutch mechanism, the shade or hem bar encounters each guide or ring, the fabric overlaps such that the fabric pleasantly cascades over the last folded portion.
[0004] While the lift cord mechanism for Roman Shades or Blinds results in a highly functional and aesthetically pleasing shade, the design of Roman Shades or Blinds can result in possible safety hazards to young children through the forming of cord loops in the lift cords, and the point of connection between the bottom of the shade or hem bar presents a point where a child may be trapped between the cord and the shade. While this risk is significantly mitigated by the use of a passive restraint system, such as a quality clutch mechanism or a motorized lift system, that prevents the lift cords from being pulled back through the headrail, thereby making it extremely difficult for a child to form a loop, clutch mechanisms and/or motorization options can be an expensive option so having an inexpensive device, such as is proposed here, would be a benefit, particularly for individuals with lower incomes. As such, a functional lift cord release device that would reduce entanglement in the lift cord or in the Roman Blinds or Shades by children would be appreciated.
[0005] Additionally, the development of a device that can be easily and intuitively put back together after separation, (whether intentional or accidental) is desirable for consumers. The use of a lift ball, as opposed to a geometrically shaped catch, means that it is fairly obvious to an end user how to reattach the mechanism after the lift ball has been separated from the spring release.
[0006] Additionally, a lift cord release that would be operable to allow removal of the Roman Shades from the head rail or other hardware systems for maintenance, repair, or cleaning would be greatly appreciated. However, present releases such as those disclosed in U.S. Pat. No. 7,302,738 to Nien et al, do not allow for the simple removal of a cord release, as the release mechanisms are often larger than any rings through which the lift cord passes. Conversely, those releases that would allow the lift cord to retreat through each guide or ring allow the lift cord to be pulled entirely through the lift mechanism or clutch in the head rail, often resulting in an extended repair job that requires the disassembly of the head rail, or a nonfunctional unit. As such, a lift cord release that reduces the likelihood of child entanglement and allows disassembly of the Roman Shade or Blind without the requirement of restringing the lift mechanism would be greatly appreciated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a rear plan view of a Roman Blind having a cord release according to one embodiment.
[0008] FIG. 1A is an enlarged view of a cord release on the Roman Blind of FIG. 1 according to at least one embodiment of the present application.
[0009] FIG. 2 is a rear plan view of a Roman Blind having a cord release according to at least one embodiment, and where the lift ball has been released from a spring release.
[0010] FIG. 2A is an enlarged view of a lift ball traveling through the cord guides of the Roman Blind of FIG. 2 according to at least one embodiment of the present application.
[0011] FIG. 3 is a side cross-section view of a lift ball according to at least one embodiment.
[0012] FIG. 4 is a top plan view of a lift ball according to at least one embodiment.
[0013] FIG. 5 is a side plan view of a cord release according to at least one embodiment, showing a lift ball within a spring release.
[0014] FIG. 6 is a side plan view of a cord release according to at least one embodiment, showing a lift ball pulled out of the spring release.
[0015] FIG. 7 is a side plan view of a spring clip according to at least one embodiment.
DESCRIPTION
[0016] Turning now to FIG. 1 , according to at least one embodiment, a Roman Blind 10 incorporating a lift release is shown from the perspective of the back side of Roman Blind 10 . According to at least one embodiment, Roman Blind 10 comprises head rail 20 , through which lift cords 30 are routed and controlled through conventional pull mechanisms or clutch mechanisms known in the art (not shown). Optionally, a clutch mechanism using a gear reduction unit as known in the art may be utilized to reduce the amount of vertical movement of Roman Blind 10 per each actuation by a user. Additionally, lift cords 30 are routed through cord guides 40 attached to shade material 50 at predetermined intervals via attachment means 100 or other means, with lift cords 30 ultimately attaching to Roman Blind 10 at hem rail 60 through cord release 70 . As shown in FIG. 1A , cord release 70 comprises lift ball 74 to which lift cord 30 is attached, and spring retainer 76 , which is attached to hem rail 60 or other suitable portion of shade material 50 .
[0017] It will be appreciated that according to at least one exemplary embodiment, and as shown in FIG. 2A , lift ball 74 is sized to be smaller than the interior diameter of cord guides 40 , thereby allowing lift ball to be freely pulled through cord guides 40 when lift ball 74 is not releasably attached to spring retainer 76 . Conversely, according to at least one exemplary embodiment, the overall size of cord release 70 when lift ball 74 is attached to spring retainer 76 as shown in FIG. 1A , the overall size of cord release 70 is greater than the interior diameter of cord guides 40 , thereby precluding cord release 70 from traveling through cord guides 40 when lift ball 74 is attached to spring retainer 76 . Functionally, such a sizing allows lift cords 30 to urge cord release upward when a user engages the lifting mechanism, thereby allowing the cord to travel upward, pulling the hem rail 60 upward and likewise gathering up shade material 50 in a cascading effect as each cord guide is pulled upward as it is encountered by cord release 70 and/or hem rail 60 . As an optional embodiment, it will be appreciated that cord release 70 may be sized to be smaller than the interior diameter of cord guides 40 without adversely affecting the function of the cord lifting action. For example, since spring retainer 76 is attached to hem rail 60 or any other suitable portion of shade material 50 , it will be appreciated that cord guides 40 cannot pass over hem rail 60 or any other suitable portion of shade material 50 as lift cords 30 are being urged upward toward head rail 20 .
[0018] Turning now to FIGS. 3 , 4 , and 5 , according to at least one embodiment, lift ball 74 is a substantially cylindrical or spherical ball sized to be larger than an opening defined by spring arms 80 of spring retainer 76 . As such, because spring arms 80 optionally comprise a material operable to be urged apart when an amount of force greater than a preselected amount is applied outwardly and/or upwardly against spring arms 80 , lift ball 74 is operable to be inserted within spring retainer 76 even though the diameter of lift ball is designed to be larger than the opening defined by spring arms 80 . Further, it will be appreciated that spring arms 80 and/or spring retainer 76 are optionally comprised of a resilient material, thereby allowing lift ball 74 to enter within the opening defined by spring arms 80 to be releasably inserted to spring retainer 76 . For example, spring arms 80 and/or spring retainer 76 may comprise a spring steel, steel, resilient plastic, or other material operable to allow lift ball 74 to be releasably inserted within spring retainer 76 . Likewise, it will be appreciated that the force necessary to insert and/or remove lift ball 74 from within spring retainer may be adjusted by varying the thickness of spring arms 80 , the material from which spring arms 80 or spring retainer 76 , by varying the opening defined by spring arms 80 , or by varying the diameter of lift ball 74 . By changing these variables, the force required to release lift ball 74 from spring retainer 76 can be altered to ensure that the pulling force required to separate lift cord 30 from hem rail 60 is low enough to release the two elements prior to causing a choke hazard, but that the force is sufficient to maintain the elements together under average working conditions for Roman Blind 10 .
[0019] Additionally a spring clip (a.k.a. “Alligator Clip”) may be used. By using an inner spring controlling the release force needed to pull the lift ball 74 from the spring retainer 76 may be easier to control in manufacturing. Turning now to FIG. 7 , a spring clip 100 is shown as an alternative embodiment of a spring retainer 76 . In practice, a spring clip 100 includes clip arms 110 , a pivot hinge 120 , spring 130 , and, optionally, a tension adjustment mechanism 140 . In operation, lift ball 74 is retained between clip arms 110 , and spring 130 urges clip arms toward lift ball 74 to retain lift ball 74 within spring clip 100 unless sufficient force to lift cord 30 pulls lift ball 74 from spring clip 100 . In operation, spring 130 may be sized and shaped to adjust the force required to release lift ball 74 from spring clip 100 . Alternatively, a tension adjustment mechanism 140 may be utilized to allow a user to adjust the spring tension applied to spring clip 100 such that as tension adjustment mechanism may be turned in one direction to compress spring 130 and thereby increase the tension, or turned in the opposite direction to release compressive forces on spring 130 , and thereby decrease the tension and therefore the amount of force necessary to remove lift ball 74 from spring clip 100 .
[0020] Furthermore, in the manufacturing of a releasable spring clip 100 it should be appreciated that different springs 130 may be utilized, with different characteristics, such as spring wire thickness or the numbers of turns in the spring to adjust the release tension of spring clip 100 to the desired level.
[0021] It will be appreciated that placing a lift ball 74 back into releasable spring clip 100 is facilitated by squeezing the lower portion of clip arms 110 , thereby facilitating an easier return of lift ball 74 to spring clip 100 after it has been released, or during the process of manufacturing the shade when the lift cords have to be adjusted in order to ensure all lift cords are tied off at the same length so that the blind raised evenly. This improved ease of removal and replacement is further useful to the end consumer who may wish to remove the shade for cleaning.
[0022] It will be appreciated that the total force required to pull lift ball 74 from spring retainer 76 should vary depending upon the total weight of hem rail 60 and shade material 50 , as well as the total number of lift cords 30 utilized in the particular shade design. According to at least one embodiment, the total force required to pull lift ball 74 from spring retainer 76 is no more than about 5 lbs. more than the total weight of the hem rail 60 divided by the total number of lift cords 30 ; is no more than about 4 lbs. more than the total weight of the hem rail 60 divided by the total number of lift cords 30 ; is no more than about 3 lbs. more than the total weight of the hem rail 60 divided by the total number of lift cords 30 ; is no more than about 2 lbs. more than the total weight of the hem rail 60 divided by the total number of lift cords 30 ; or is no more than about 1.5 lbs. more than the total weight of the hem rail 60 divided by the total number of lift cords 30 .
[0023] According to at least one embodiment, the total force required to pull lift ball 74 from spring retainer 76 may be calculated by the amount of force required to pull a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop. According to at least one embodiment, the total force required to pull lift ball 74 from spring retainer 76 is no more than about 5 lbs. of force exerted on a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop; is no more than about 4 lbs. of force exerted on a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop; is no more than about 3 lbs. of force exerted on a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop; is no more than about 2 lbs. of force exerted on a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop; or is no more than about 1.5 lbs. of force exerted on a single lift cord 30 at approximately 90 degrees to the shade material 50 to form a loop.
[0024] According to at least one embodiment, lift ball 74 is a substantially cylindrical or spherical ball sized to be smaller than cord guides 40 to allow lift ball 74 to pass through cord guides in the event that lift ball 74 is released from spring retainer 76 . As shown in FIG. 2A , cord guides 40 is optionally be a ring-shaped structure attached to shade material 50 , or cord guides 40 may be another looped cord or openings within shade material 50 that allow lift ball 74 to be passed through shade material 50 . In at least one exemplary embodiment, lift ball 74 is sized to have a diameter of at least 0.01″ smaller than the inside diameter of cord guides 40 . According to at least one additional embodiment, lift ball 74 is sized to have a diameter of at least 0.125″ smaller than the inside diameter of cord guides 40 . According to at least one additional embodiment, lift ball 74 is sized to have a diameter of at least 0.25″ smaller than the inside diameter of cord guides 40 .
[0025] According to at least one embodiment, lift ball 74 is sized larger than any openings within head rail 20 , thereby preventing retraction of attached lift cord 30 within head rail 20 . According to at least one embodiment, ball 74 is sized to have a diameter of at least 0.01″ larger than the largest opening in head rail 20 .
[0026] Turning now to FIGS. 3 and 4 , a side cross section and top plan view of at least one embodiment of lift ball 74 is provided. As shown therein, lift ball 74 is substantially spherical, and includes at least one hollow channel 90 whereby at least one lift cord 30 is operable to pass therethrough. It will be appreciated that hollow channel 90 is optionally sized such that after passing the at least one lift cord 30 through hollow channel 90 , the at least one lift cord 30 may be tied into a knot such that the knot cannot pass through hollow channel 90 . Such a method of construction allows assembly of Roman Blind 10 to be more easily accomplished, as often lift cords 30 must be adjusted at the factory or upon purchase to ensure that lift cords 30 are of an appropriate length to ensure that hem rail 60 hangs horizontally and is retracted at the same rate when operated. Allowing adjustment through tying one or more knots in one or more lift cords 30 allows for a substantially easier adjustment of how hem rail 60 hangs.
[0027] In at least one other embodiment, lift ball 74 may comprise a spring-loaded stop that substantially pinches the one or more lift cords 30 within hollow channel 90 , similar to those stops available under the ORB brand name and available from RollEase, Inc.
Example
[0028] According to at least one exemplary embodiment, a chart for calculating the force to release a lift ball 74 from spring retainer 76 is provided. It will be appreciated that utilizing a release weight low enough to prevent potential strangulation or entanglement while still maintaining an operable blind may be difficult, particularly when a typical pull cord blind is utilized. A relatively low release weight plays against the desire for lift ball 74 not to accidentally separate from spring release 76 during normal operation. As such, Table 1 below establishes a calculation format easily utilized by manufacturers of roman blinds to calculate the minimum number of lift cords 30 lift to be utilized when manufacturing a blind so that the weight needed to lift the blind is no more than 1.5 pounds on average per lift cord. To utilize the calculation format shown below, a manufacturer supplies: the weight in grams per meter or ounces per square yards of the fabric (or fabrics, in the case of a lined shade) used, the weight of the “battens” or cross bars used (if any), the number of cross bars used in a given length of a shade and the weight of the hem rail 60 .
[0029] As an example, Table 1A shows a size grid and the weight of a shade in each size (exclusive of the headrail or pulley mechanism) for roman shades with cross bars (or battens) in sizes up to 144″ (width)×150″ (length) using a typical fabric that weighs 9 ounces per square yard, a fiberglass hem rail 60 that weighs 1.6 oz per linear foot and battens (or cross bars) that weigh 0.6 oz per linear foot and are spaced about 9″ apart. From this weight chart, a manufacturer can deduce how many lift lines to use so that the weight per lift line is no more than 1.5 pounds, as shown in Table 1B, which can optionally be used in conjunction with Table 1A. This type of calculation can be easily done by someone who is relatively versed in the program “Excel,” and can modify the chart or calculation to ensure that each lift cord has a proper release weight while maintaining sufficient overall force to allow operation of the shade. Moreover, as Table 1 shows, lift lines do not have to be spaced more closely than 12″ apart, which is reasonable for manufacturers of roman shades.
[0000]
TABLE 1A
Weight of a roman blind (in pounds) using:
Shade fabric
9
oz/sq
weighting
yard
Battens
0.6
oz per
Weighing
foot
Hem rail
1.6
oz per
weighing
foot
Hem rail Weight
4.80
6.40
8.00
9.60
11.20
12.80
14.40
16.00
17.60
19.20
(Ounces)
Weight per
1.80
2.40
3.00
3.60
4.20
4.80
5.40
6.00
6.60
7.20
batten
(Ounces)
Width of Shade in Inches
Battens
Length in Inches
36
48
60
72
84
96
108
120
132
144
(9″ avg.)
36
1.20
1.60
2.00
2.40
2.80
3.20
3.60
4.00
4.40
4.80
3
42
1.41
1.88
2.34
2.81
3.28
3.75
4.22
4.69
5.16
5.63
4
48
1.61
2.15
2.69
3.23
3.76
4.30
4.84
5.38
5.91
6.45
5
54
1.71
2.28
2.84
3.41
3.98
4.55
5.12
5.69
6.26
6.83
5
60
1.91
2.55
3.19
3.83
4.46
5.10
5.74
6.38
7.01
7.65
6
66
2.12
2.83
3.53
4.24
4.94
5.65
6.36
7.06
7.77
8.48
7
72
2.33
3.10
3.88
4.65
5.43
6.20
6.98
7.75
8.53
9.30
8
78
2.42
3.23
4.03
4.84
5.64
6.45
7.26
8.06
8.87
9.68
8
84
2.63
3.50
4.38
5.25
6.13
7.00
7.88
8.75
9.63
10.50
9
90
2.83
3.78
4.72
5.66
6.61
7.55
8.49
9.44
10.38
11.33
10
96
3.04
4.05
5.06
6.08
7.09
8.10
9.11
10.13
11.14
12.15
11
102
3.13
4.18
5.22
6.26
7.31
8.35
9.39
10.44
11.48
12.53
11
108
3.34
4.45
5.56
6.68
7.79
8.90
10.01
11.13
12.24
13.35
12
114
3.54
4.73
5.91
7.09
8.27
9.45
10.63
11.81
12.99
14.18
13
120
3.75
5.00
6.25
7.50
8.75
10.00
11.25
12.50
13.75
15.00
14
126
3.96
5.28
6.59
7.91
9.23
10.55
11.87
13.19
14.51
15.83
15
132
4.05
5.40
6.75
8.10
9.45
10.80
12.15
13.50
14.85
16.20
15
138
4.26
5.68
7.09
8.51
9.93
11.35
12.77
14.19
15.61
17.03
16
144
4.46
5.95
7.44
8.93
10.41
11.90
13.39
14.88
16.36
17.85
17
150
4.56
6.08
7.59
9.11
10.63
12.15
13.67
15.19
16.71
18.23
17
[0000]
TABLE 1B
Minimum
Number of Lift
Cords to be
Used to keep
weight per lift
cord below 1.5
pounds per lift
cord
36
48
60
72
84
96
108
120
132
144
36
1
1
1
2
2
2
2
3
3
3
42
1
1
2
2
2
3
3
3
3
4
48
1
1
2
2
3
3
3
4
4
4
54
1
2
2
2
3
3
3
4
4
5
60
1
2
2
3
3
3
4
4
5
5
66
1
2
2
3
3
4
4
5
5
6
72
2
2
3
3
4
4
5
5
6
6
78
2
2
3
3
4
4
5
5
6
6
84
2
2
3
4
4
5
5
6
6
7
90
2
3
3
4
4
5
6
6
7
8
96
2
3
3
4
5
5
6
7
7
8
102
2
3
3
4
5
6
6
7
8
8
108
2
3
4
4
5
6
7
7
8
9
114
2
3
4
5
6
6
7
8
9
9
120
3
3
4
5
6
7
8
8
9
10
126
3
4
4
5
6
7
8
9
10
11
132
3
4
5
5
6
7
8
9
10
11
138
3
4
5
6
7
8
9
9
10
11
144
3
4
5
6
7
8
9
10
11
12
150
3
4
5
6
7
8
9
10
11
12
[0030] To further ensure that lift ball 74 does not accidentally separate from the spring release during operation, manufacturers of roman shades may optionally utilize a clutch mechanism with a gear reduction as the means of lifting the shade. A clutch mechanism with a gear reduction system, such as is commercially available from RollEase of Stamford Conn. or Coulisse of the Netherlands prevents end user from “jerking” the blind up quickly, thereby reducing the chance of accidental separation of lift ball 74 from spring release 76 during normal operation.
[0031] It will further be appreciated a lift ball 74 and spring release 76 may be sold in a kit form to retrofit existing roman shades to allow them to break away. For example, lift ball 74 may be included with spring release 76 , with spring release 76 including a hole in its base operable to receive a screw or other fastener such that spring release 76 is attached to hem rail 60 . Additionally, cord guides 40 may be included such that cord guides 40 that are sized to allow lift ball to travel through them upon release, may be included, along with a means for attaching cord guides 40 to existing roman blind 10 . As such, through the sale of these elements in a unitary package, existing roman blinds 10 may be retrofitted into a safer or more convenient product.
[0032] While specific embodiments have been disclosed herein, combinations of those embodiments, as well as certain variations thereof are included in the scope of this application.
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The present invention relates to a novel release mechanism for Roman Blinds or similar window treatments, whereby a cord release comprising a lift ball releasably attached to a spring release allow for effective operation of a Roman Blind or similar window treatment under normal operation, but allow release of a lift cord from the hem rail and through lift cord guides in the event that a child becomes entangled therein, or in the event that a user wishes to remove the shade material from the head rail.
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BACKGROUND OF THE INVENTION
The present invention relates to an improved slat for blinds such as Venetian and vertical blinds.
A Venetian blind typically includes a number of slats in the form of elongated thin plates generally made of light metals such as Al or Al alloys. The slats are connected to each other in vertical superposition by means of ladder tapes. By manual operation on a lift cord, the slats are collected upwards in order to open the blind. Further, by manual operation on a tilt cord, angle of the slats are concurrently changed in order to adjust the amount of light passing through the blind.
Each slat is given in the form of a thin metallic plate coated on both faces with opaque colours. Optionally grain pattern printing may be applied to the faces of the thin plate.
A slat for blinds is in general expected to fulfill the following properties.
(I) It should give a rich woody impression and have a highly aesthetic appearance.
(II) It should have sufficient strength together with flexibility high enough to toughly recover from bending and contortion.
(III) It should have a thickness of about 1 mm or smaller but, nevertheless, not lose structural stability.
(IV) It should be impervious to changes in environmental conditions such as temperature and humidity.
The above-described conventional slat does not meet these requirements. First its appearance is rather simple and poor in aesthetic effect. When a blind is swayed by wind, metallic slats frequently collide against each other to generate harsh noises. When used in a wet environment such as a bathroom direct contact of metallic slat with moisture in the air can easily cause the formation of dew as a result of the high thermal conductivity of the metallic material on the slats leads to quick corrosion problem. In addition, the relatively thin construction of the conventional metallic slats is in most cases incompatible with their structural stability and rich recoverbility from bending and contortion.
SUMMARY OF THE INVENTION
It is the basic object of the present invention to provide a sufficiently aesthetic slat for blinds which is sufficiently rich in strength and flexibility.
It is another object of the present invention to provide a thin but structurally stable slat for blinds which is highly impervious to changes in environmental conditions.
In accordance with the basic aspect of the present invention, a slat for blinds includes an elongated core plate and at least two elongated surface layers laminated on bath faces of the core plate via intermediates.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a transverse cross-sectional view of one embodiment of the slat in accordance with the present invention,
FIGS. 2A to 2C are transverse cross-sectional views of various types of configurated slats in accordance with the present invention,
FIG. 3 is a fragmentary sectional view of another embodiment of the slat in accordance with the present invention accompanied with printed decoration patterns,
FIG. 4 is a transverse cross-sectional view of another embodiment of the slat in accordance with the present invention,
FIG. 5 is a transverse cross-sectional view of the other embodiment of the slat in accordance with the present invention, and
FIGS. 6 and 7 are transverse cross-sectional views of still other embodiments of the slat in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
One embodiment of the slat in accordance with the present invention is shown in FIGS. 1 and 2, in which a slat 2 is made up of a metallic center plate 3, a pair of wooden plates 6 and 7 bonded to opposite faces of the center plate 3 by means of bond layers 4 and 5 and a pair of synthetic resin layers 8 and 9 coated on the exposed faces of the wooden plates 6 and 7.
In production of such a slat 2, and Al or Al alloy plate of, for example, 0.2 mm thickness is formed into a core plate 3 by cutting and both faces of the core plate 3 are coated with a bond such as urethane emulsion at a density of 100 g/m 2 . Next, wooden plates 6 and 7 made of, for example, American walnut of 0.1 to 0.3 mm, more preferably 0.2 mm thickness, are attached to the coated faces of the core plate 3. The combination is heated at 150° C. under a pressure of 1.0 to 2.0 MPa for 5 min. Thereafter, the exposed faces of the wooden plates 6 and 7 are ground by grinding papers of #240 to #400 and next coated with colours made of urethane resin. After middle coating, the faces are again ground with grinding papers of #240 to #400 and subjected to finish coating to form the synthetic resin layers 8 and 9. By properly slicing the product, a flat slat such as shown in FIG. 2A is obtained. Optionally, configurated slats such as shown in FIGS. 2B and 2C can be obtained by proper press or roll forming.
Optionally, the synthetic resin layers 8 and 9 may be of transparent films. In this case, after the above-described middle coating, acrylic films of, for example, 35 μm thickness are applied to the coated faces of the wooden plates 6 and 7 and the combination is heated at 130° C. under a pressure of 2.0 MPa for 5 min to fuse of the films. Further, as shown in FIG. 3, decoration patterns 10 may be formed on at least one synthetic resin layer 8 or 9 by means of screen or gravure printing.
In one alternative, wooden plates 6 and 7 of 0.2 mm thickness may be used with non-woven fabric backings of 30 g/m 2 density. Pigments are preferably used for colour coating of the wooden plates 6 and 7. Further, in formation of the synthetic resin layers 8 and 9, a transparent film for the front side face may be used in combination with an opaque film for the rear side face of the slat 2.
In accordance with the present invention, the presence of the wooden plates on both faces of the metallic core plate restrains generation of harsh noises due to colliding of slats and thermal insulation by the wooden plate lowers the possibility of dew formation even when the slats are used in a humid environment. Further, presence of the wooden plate on the surface region of the slat well enhances its aesthetic value.
Another embodiment of the slat in accordance with the present invention is shown in FIG. 4, in which, as a substitute for the metallic core plate 3 used for the foregoing embodiment, a core plate 13 is made of fiber reinforced plastic (FRP).
In production of such a slat 2', a glass cloth of 100 g/m 2 density is coated with thermosetting resin such as powdery epoxy resin of 100 g/m 2 and the combination is heated at 130° C. under a pressure of 1.0 MPa for 20 min to form an FRP core plate 13 of thermal deformation at 105° C. Subsequent steps are substantially same as those employed in production of the foregoing embodiment.
Use of FRP for the core plate further reduces generation of noises due to colliding of slats.
The other embodiment of the slat in accordance with the present invention is shown in FIG. 5. The construction of this slat 2 is substantially same as that of the slat shown in FIG. 1 with the exception that side faces of the slat 2 are coated with synthetic resin layers 21 and 22 whose colour is close to that of the wooden plates 6 and 7. Thanks to presence of these synthetic resin layers 21 and 22, the side faces of the metallic core plate 3 are not exposed. The side faces of the slat 2" may additionally be furred. In this case, for example, the side faces of the slat are spray coated with urethane bond and, next, the slat is dipped in a bath filled with short fibers. The obtained slat has an appearance like a woven fabric.
In the other embodiment of the slat in accordance with the present invention, side faces of a slat are covered with anodic oxide layers. Such layers are formed by application of anodic oxidization and each produced slat has an elegant bronze colour of invar tint.
The presence of such additional side face layers shields the metallic core plate against corrosion otherwise caused by direct contact with the air.
Still other embodiments of the slat in accordance with the present invention are shown in FIGS. 6 and 7.
In the case of the embodiment shown in FIG. 6, the slat 30 includes a wooden core plate 31, a pair of reinforcements 33 bonded to both faces of the core plate 31 by means of bond layers 32 and a pair of wooden plates 35 bonded to the faces of the reinforcements 33 by means of bond layers 34.
The wooden plates 31 and 35 are made of, for example, White oak, American wall nut and oak. The plate may accompany a non-woven fabric backing. The thickness of the plates is preferably in a range from 0.15 to 0.30 mm. In preparation, the wooden material may be impregnated with synthetic resin for high strength and structural stability. For example, a material plate may be impregnated in a synthetic resin bath at 50° C. for 1 to 24 hours. Preferably, ethylene glycol resin, acrylic resins and urethane resins are used for the bath.
The reinforcements 33 are made of, for example, cloths, non-woven fabrics and resin sheets made of glass fibers and synthetic fibers such as polymides and polyesters. A thickness from 0.03 to 0.10 mm is preferably employed. The density of the cloth and resin sheet is preferably be 50 g/m 2 or smaller. The resin sheet is preferably made of acrylic resins and polypropylene resins and its thickness is about 0.10 mm. Use of such resin sheets results in strong bonding between the superposed elements thanks to soaking of the bond layers into those sheets during heat press bonding.
In the case of the embodiment shown in FIG. 7, synthetic resin layers 36 are further formed on the faces of the wooden plates 35.
In lamination of the wooden plates 31 and 35, the grain directions of different wooden plates are parallel, normal or oblique to each other. Preferably, grain directions of different wooden plates should differ from each other a little so that strength and swelling of the slat are uniform in different directions.
The above-described metallic core plate is preferably made of Al, Al alloys, Fe and Fe alloys.
For bonding of adjacent plates, urethane resins, epoxy resins, or the like are usable.
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A slat for blinds such as Venetian blinds made up of a core plate made of metal, FRP or wood and a pair of surface layers laminated on both faces of the core plate via intermediates. The laminated construction well suppresses generation of harsh noises otherwise caused by slat colliding and dewing even when used in wet environments.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to snow plows. More particularly, the invention relates to a hinged snow plow for use on off-road vehicles. The snow plow is designed so that an adapter bracket is easily mounted to a tubular frame which is made in many variations so that the snow plow of the present invention can be mounted to practically any off-road vehicle.
2. Description of the Prior Art
Hinged snow plows have been known in the art for many years in relationship to the mounting of various types of snow plows on pickup trucks for use on commercial settings. One such snow plow that is known is disclosed in U.S. Pat. No. 4,658,519, issued on Apr. 21, 1987, to Phillip J. Quenzi. This patent discloses a hinged snow plow wherein a cowling is pivotally secured to the free end of a support frame which attaches to a vehicle in a manner such that the cowling pivots in a generally vertical plane about the free end of the frame. The blades of the snow plow are hinged to the cowling. However, this snow plow has a first and second stop means which are undesirable for use in off-road vehicles. Off-road vehicles generally lack adequate traction and are underpowered for moving and clearing areas of snow on a commercial basis or for expanded personal use. The provision of the stop means on the Quenzi snow plow under certain conditions requires additional power which the off-road vehicle simply does not have. Also, the hydraulic adjustment means are impractical for use on off-road vehicles since a source of hydraulic power is just not available. The U.S. Pat. No. 3,307,275, issued on Mar. 7, 1967 to E. A. Simi, and the U.S. Pat. No. 3,706,144, issued Dec. 19, 1972 to Miceli, also suffer from one or more of these problems. Thus, those skilled in the snow plow art have continued to search for solutions to these problems.
SUMMARY OF THE INVENTION
To solve the problems in the prior art, a hinged snow plow is provided wherein a cowling is pivotally secured to the free end of an adapter. The adapter, which may be of a multi-piece construction, attaches to a tubular mounting means of a universal nature which is modified in a manner depending upon the vehicle the off-road snow plow is to be mounted to. The combination of the adapter and the tubular frame make the snow plow of the present invention mountable to almost any off-road vehicle. The cowling is mounted to a pivot means which allows it to pivot in a generally vertical plane about the adapter and is free to rotate virtually 360 degrees about said vertical plane to prevent any artificial stop means from acting during the operation of the snow plow. The blades of the hinged snow plow are hinged to the cowling, and a manual adjustment means is provided for positioning the blades so that a hydraulic source of power is not needed on the off-road vehicle.
Thus, it is an object of the present invention to provide an improved hinged snow plow usable on an off-road vehicle.
A further object of the present invention is to be provide a hinged off-road vehicle snow plow without artificial stop means to limit the tilting of the blades.
A still further object of the present invention is to provide a hinged snow plow for use on off-road vehicles having a manual adjustment means.
A still further object of the present invention is to provide a hinged off-road vehicle snow plow which does not require a source of hydraulic power for adjustment.
A still further object of the present invention is to provide an off-road vehicle snow plow which is easily mountable to a wide variety of off-road vehicles.
Further objects and advantages of the present invention will be apparent from the following description and depended claims, reference being made to the accompanying drawings forming a part of the Specification, wherein like reference characters designate corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the snow plow of the present invention mounted to the front of an off-road vehicle.
FIG. 2 is a perspective view of a portion of the snow plow of the present invention showing a tubular mounting frame, an adapter mounted to the end of the tubular mounting frame, and a cowling adapted to rotate 360 degrees in a vertical plane about the adapter.
FIG. 3 is an exploded view of the snow plow of the present invention.
FIG. 4 is a partial elevational view of the snow plow of the present invention showing an embodiment of the manual adjustment means.
It is to be understood that the present invention is not limited to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments, and is capable of being practiced or carried out in various ways within the scope of the claims. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown an off-road vehicle, generally designated by the numeral 20 , supported by one or more ground engaging tires 21 . Mounted to the midpoint of the offroad vehicle frame or the forward end of A Lawn Tractor vehicle 20 is the snow plow of the present invention, generally designated by the numeral 25 . The snow plow includes a pair of plow blades 26 which are hinged together at the hinge 27 provided on the cowling 28 . Cowling 28 is mounted on the free end of multi-piece adapter 30 . The plow blades 26 may be of a standard rectilinear shape well known in the art. Each blade hinge 27 includes a plurality of hinge collars 33 , some of which are formed, welded or otherwise attached to the blade 26 , and some of which are formed, welded or otherwise attached to the cowling 28 . Vertically aligning the hinge collars 33 on the blades 26 with the hinge collars 33 on the cowling 28 , and inserting the hinge pin 31 through the aligned openings formed thereby, hingedly attaches blades 26 to the cowling 28 and allows them to freely rotate about the pin 31 , unless restrained by another means.
The blades 26 may be held in several preset desired positions. They may be set in the shape of a forward V, a reverse V, or a straight line configuration. The straight line configuration may be transverse to the axis of the off-road vehicle, or set at a desired angle. An adjustment means may include a pair of brackets 36 to which are mounted a pair of restraining means, such as radius rods 38 , by means well known in the art. A plurality of holes 39 are provided proximate each end of the radius rods 38 for purposes to be described. The radius rods are passed between the upper portion 40 and the lower portion 41 of the cowling 28 and the desired pair of holes 39 are aligned. Pin means, to be described below, are used to hold the plow blades 26 in the desired position. A right angle portion 38 A provided on the end of each rod 38 prevents the rods from accidentally coming out of the cowling when the blades are adjusted.
Referring now to FIG. 4, it can be seen that the holes 39 in the radius rods 38 can be placed in vertical alignment with a hole 43 provided in the upper portion 40 of the cowling 28 , cowling bracket hole 44 , and lower cowling hole 46 . Passing through holes 43 , 44 , 39 and 46 is the spring loaded pin 42 which is maintained in a spring loaded condition by virtue of the spring 45 surrounding the spring loaded pin 42 and acting between the inner upper surface of the cowling bracket 48 and the washer 49 . The washer is pinned to the spring loaded pin 42 by the transverse pin 50 by means well known in the art. It can be seen that lifting the pin 42 such that its lower end disengages from the holes 39 , and the radius rods 38 , allows the plow blades to be set in any desired position.
To allow the plow blades to pivot when obstacles are encountered, the lower portion of the cowling 28 has pivot means provided therein in the form of an elongated bearing 52 into which the pivot pin 53 fits to provide for rotation of the cowling 28 and thereby of the plow blades 26 . Of importance to the present invention is the fact that the cowling, when the plow blades are unattached, can pivot 360 degrees between the arms 54 of the adapter 30 , restrained only by the vertical stop 75 .
In operation, however, the plow blades 26 will be attached to the cowling 28 by the hinge 27 to hold the plow blades 26 in a generally vertical position. A spring bracket 55 is provided on the upper portion 40 of the cowling 28 and spring mounting holes 56 are provided in the bracket 55 as well as in the tab portions 76 provided on arms 54 forming a portion of the adapter 30 . A stiffening plate 77 , secured between the ends of tubular frame 65 , is also considered part of the adaptor 30 . A pair of tension providing springs 58 are mounted in a parallel relationship in the holes 56 as illustrated in FIG. 3 .
As shown in FIG. 4, when the plow blades 26 hit an obstruction, the plow blades may tilt forward or rearward as needed to overcome the obstruction. Skids 60 of a type well known in the art may be provided to keep the plow blades 26 at a proper height above the surface being plowed. These skids may either be of a fixed or adjustable nature. Depending on the application to which the plow of the present invention is to be put, reinforcements 51 may be provided on the rear of the plow blades 26 if needed. These may be provided in combination with the brackets 36 if desired.
Referring now to FIG. 2, the universal nature of the improved snow plow of the present invention can be observed. It can be seen that the adapter 30 is mounted to the tubular frame 65 by any suitable means. The frame 65 may have suitable reinforcements 66 , and mounting means 67 , which may have mounting holes 68 provided therein. The mounting means 67 may take a wide variety of forms as needed to provide for the mounting of the tubular frame to the midpoint of the particular off-road vehicle or the front of lawn tractor being used. The mounting means should be understood broadly to include whatever attachments are needed to the tubular frame 65 to mount the improved snow plow to an off-road vehicle.
As can be seen in FIGS. 1 and 2, a bracket 70 may also be mounted to the adapter 30 , and connected by a control rod 71 , to a bell crank 73 mounted to off road vehicle 20 . Bell crank 73 is connected, in turn, to operating lever 74 by second control rod 79 . Operating lever 74 can be operated, such that the off-road vehicle operator may raise and lower the snow plow as desired.
If a simplified construction of the snow plow blade positioning means is desired, instead of the spring loaded pin 42 , a non-spring loaded pin (not shown) may be provided.
Thus, by carefully studying the available prior art snow plows, and the capability of off-road vehicles, I have provided a novel off-road vehicle snow plow.
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A hinged snow plow for an off-road vehicle is provided wherein a cowling is pivotally secured to the free end of an adapter. The adapter attaches to a tubular mounting means of a universal nature. The tubular mounting means which is modified, depending upon the off-road vehicle to which the snow plow is to be mounted. The combination of the adapter and tubular frame make the snow plow mountable to almost any off-road vehicle.
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BACKGROUND OF THE INVENTION
Polymer drug delivery systems have been developed for the controlled release of pharmaceutical polypeptides. For example, synthetic polyesters such as poly(DL-lactic acid), poly(glycolic acid), poly(lactic-glycolic acid), and poly(ε-caprolactone) have been used in the form of microcapsules, films, or rods to release biologically active polypeptides. See e.g., U.S. Pat. Nos. 4,767,628 and 4,675,189 and PCT Application No. WO 94/00148.
In addition to the synthetic polymeric chains, natural polymers and their derivatives have been used as components in similar sustained release compositions that dissociate by enzymatic degradation. One example of such natural polymers are those based on chitin, a poly(N-acetylglucosamine). However, since chitin is water insoluble, others have examined solubilizable derivatives which are based primarily on a partially deacetylated chitin, e.g., chitosan. See e.g., Sanford, P. A. et al., Eds., Advances in Chitin & Chitosan (1992). Although chitosan can be found in some fungi, the production of biodegradable chitosan is generally performed synthetically. See Mima, et. al., J. Appl. Polym. Sci. 28:1909-1917 (1983). Synthetic derivatives of chitosan have also been prepared to alter the polymer's in vivo biological characteristics. See Muzzarelli, et al., Carbohydrate Res. 207:199-214 (1980).
The use of chitin, as well as chitin derivatives, has been proposed in a number of drug delivery systems. See, e.g., European Patent Application Nos. 486,959, 482,649, 525,813 A1, and 544,000 A1; and U.S. Pat. No. 5,271,945.
SUMMARY OF THE INVENTION
In one aspect, the present invention features a copolymer including an N-acylated derivative of poly(2-amino-2-deoxy-D-glucose), wherein between 1 and 50 percent of the free amines of the poly(2-amino-2-deoxy-D-glucose) are acylated with a first acyl group, the first acyl group is COE 1 where E 1 is selected from the group consisting of C 3-33 carboxyalkyl, C 3-33 carboxyalkenyl, C 7-39 carboxyarylalkyl, and C 9-39 carboxyarylalkenyl, and between 50 and 99 percent of the free amines of the poly(2-amino-2-deoxy-D-glucose) are acylated with a second acyl group, the second acyl group is COE 2 where E 2 is selected from the group consisting of C 1-30 alkyl, C 2-30 alkenyl, C 6-37 arylalkyl, and C 8-37 arylalkenyl, provided at least one of the free amines of the derivative is acylated with the first acyl group.
The copolymer preferably has a molecular weight of about 3,000 to 90,000 daltons. In other preferred embodiments, over 90 percent of the free amines of the poly(2-amino-2-deoxy-D-glucose) are acylated with either the first acyl group or the second acyl group. Preferably, between 10 and 30 percent of the free amine of the poly(2-amino-2-deoxy-D-glucose) are acylated with the first acyl group. Some of the free hydroxy groups (e.g., between 1 and 30 percent) of the derivative may be acylated with either the first acyl group or the second acyl group.
In a preferred embodiment, the copolymer is of the formula: ##STR1## wherein: R 1 , for each individual repeat unit, is selected from the group consisting of first acyl group, second acyl group, and H;
R 2 , for each individual repeat unit, is selected from the group consisting of first acyl group, second acyl group, and H;
R 3 , for each individual repeat unit, is selected from the group consisting of first acyl group, second acyl group, and H;
R 4 is selected from the group consisting of first acyl group, second acyl group, and H;
R 5 is selected from the group consisting of first acyl group, second acyl group, and H;
R 6 is selected from the group consisting of first acyl group, second acyl group, and H;
R 7 is selected from the group consisting of COH and CH 2 OR 8 ;
R 8 is selected from the group consisting of first acyl group, second acyl group, and H;
n is between 2 and 200; and
for between 1 and 50 percent of the repeat units, R 1 is first acyl group, and for between 50 and 99 percent of the repeat units, R 1 is second acyl group, provided that for at least one of the repeat units, R 1 is first acyl group.
The terms COE 1 and COE 2 stand for --C═O.E 1 and --C═O.E 2 , respectively. The substituents carboxyalkyl, carboxyalkenyl, carboxyarylalkyl, and carboxyarylalkenyl may contain 1-4 carboxylic acid functionalities. Examples of the first acyl group include, but are not limited to, succinyl, 2-(C 1-30 alkyl) succinyl, 2-(C 2-30 alkenyl)succinyl, maleyl, phthalyl, glutaryl, and itaconyl. Examples of the second acyl group include but are not limited to, acetyl, benzoyl, propionyl, and phenylacetyl.
The present invention also features a composition including the above copolymer and a polypeptide, the polypeptide comprising at least one effective ionogenic amine, wherein at least 50 percent, by weight, of the polypeptide present in the composition is ionically bound to the polymer. Preferably, the composition comprises between 5 and 50 percent, by weight, of the polypeptide.
Examples of suitable polypeptides include growth hormone releasing peptide (GHRP), luteinizing hormone-releasing hormone (LHRH), somatostatin, bombesin, gastrin releasing peptide (GRP), calcitonin, bradykinin, galanin, melanocyte stimulating hormone (MSH), growth hormone releasing factor (GRF), growth hormone (GH), amylin, tachykinins, secretin, parathyroid hormone (PTH), enkaphelin, endothelin, calcitonin gene releasing peptide (CGRP), neuromedins, parathyroid hormone related protein (PTHrP), glucagon, neurotensin, adrenocorticothrophic hormone (ACTH), peptide YY (PYY), glucagon releasing peptide (GLP), vasoactive intestinal peptide (VIP), pituitary adenylate cyclase activating peptide (PACAP), motilin, substance P, neuropeptide Y (NPY), TSH and biologically active analogs thereof. The term "biologically active analogs" is used herein to cover naturally occurring, recombinant, and synthetic peptides, polypeptides, and proteins having physiological or therapeutic activity. In general, the term covers all fragments and derivatives of a peptide, protein, or a polypeptide that exhibit a qualitatively similar agonist or antagonist effect to that of the unmodified, or naturally occurring peptide, protein, or polypeptide, e.g., those in which one or more of the amino acid residues occurring in the natural compounds are substituted or deleted, or in which the N- or C-terminal residues has been structurally modified. The term effective ionogenic amine refers to a free amine present on the polypeptide which is capable of forming an ionic bond with the free carboxylic groups on the copolymer.
The release of the polypeptide from the composition may be modified by changing the chemical structure of the composition. Increasing the molecular weight of the polymer will decrease the rate of peptide released from the conjugate. Increasing the number of carboxylic acid groups on the polymer will increase the amount of polypeptide ionically bound to the composition, and consequently, increase the amount of release of the peptide from the conjugate.
The release of the polypeptide may be further modulated through (a) treating the composition with soluble salts of divalent or polyvalent metallic ions of weak acids (e.g., calcium, iron, magnesium, or zinc); (b) coating the particles with a thin, absorbable layer made of a glycolide copolymer or silicone oil in a spherical, cylindrical, or planar configuration; or (c) microencapsulating the composition in an absorbable glycolide copolymer. In one embodiment, the composition comprises between 0.01 and 20 percent, by weight, of a polyvalent metal.
Depending on the choice of polypeptide, the compositions can be used to treat any number of disorders. For example, somatostatin, bombesin, GRP, LHRH, and analogs thereof, have been shown to treat various forms of cancer. Growth factors such as GH, GRF, and GHRP, and analogs thereof, have been shown to stimulate growth in both adolescents and the elderly. Calcitonin, amylin, PTH, and PTHrP, and analogs thereof, have been shown to treat osteoporosis and other bone disorders.
The compositions are designed for parenteral administration, e.g., intramuscular, subcutaneous, intradural, or intraperitoneal injection. Preferably, the compositions are administered intramuscularly.
The compositions of the invention can be in the form of powder or a microparticle to be administered as a suspension with a pharmaceutically acceptable vehicle (e.g., water with or without a carrier substance such as mannitol or polysorbate). The compositions may also be compounded in the form of a rod for parenteral implantation using a trocar, e.g., intramuscular implantation.
The dose of the composition of the present invention for treating the above-mentioned diseases or disorders varies depending upon the manner of administration, the age and the body weight of the subject, and the condition of the subject to be treated, and ultimately will be decided by the attending physician or veterinarian. Such an amount of the composition as determined by the attending physician or veterinarian is referred to herein as a "therapeutically effective amount."
In another aspect, the present invention features a process of synthesizing a copolymer, the process comprising the steps of: reacting chitosan with a weak acid to produce a lower molecular weight polysaccharide; reacting between 1 and 50 percent of the free amines of the lower molecular weight polysaccharide with a first acylating agent, the first acylating agent selected from the group consisting of C 4 -C 34 polycarboxyalkane, C 4 -C 34 polycarboxyalkene, C 8 -C 40 polycarboxyarylalkane, C 10 -C 40 polycarboxyarylalkene, or an acylating derivative thereof; and reacting between 50 and 100 percent of the free amine of the lower molecular weight polysaccharide with a second acylating agent, the second acylating agent selected from the group consisting of C 2-31 monocarboxyalkane, C 3-31 monocarboxyalkene, C 7-38 monocarboxyarylalkane, C 9-35 monocarboxyarylalkene, or an acylating derivative thereof. The reaction of the lower molecular weight polysaccharide with both the first acylating agent and the second acylating agent may be measured with an amine detecting agent (e.g., fluorescamine) to ensure that between 1 and 50 percent of the free amines of the lower molecular weight polysaccharide are acylated with the first acylating agent and between 50 and 99 percent of the free amines of the lower molecular weight polysaccharide are acylated with the second acylating agent. See, e.g., Bailey, P. D., An Introduction to Peptide Chemistry (Wiley, N.Y.)(1990); Oppenheimer, H, et al. Archives Biochem. Biophys. 120:108-118 (1967); Stein, S, Arch. Biochem. Biophys. 155:203-212 (1973).
Reacting chitosan with the weak acid (e.g., nitrous acid) cleaves the polymer, thereby reducing its molecular weight (e.g., 2,500-80,000 daltons). In preferred embodiments, the first acylating group and the second acylating agent are reacted with the lower molecular weight polysaccharide successively, e.g., either the first acylating agent is reacted before the second acylating agent is reacted or the second acylating agent is reacted before the first acylating agent or simultaneously. As a result of the acylation of the free amines, some of the free hydroxy groups of the lower molecular weight polysaccharide may be acylated. The extent of the acylation of the free hydroxy groups may be altered by changing the pH or the solvents or agents used during the acylation reactions, or the acylating agents used.
Examples of acylating derivatives include, but are not limited to, anhydrides and N-acylated heterocycles (e.g., imidazoles and pyrazoles). See e.g., Bodansky, et al., The Practice of Peptide Synthesis, 87-150 (Springer-Verlag, 1984). The agents polycarboxyalkane, polycarboxyalkene, polycarboxyarylalkane, and polycarboxyarylalkene or acylating derivatives thereof contain, or originate from reactants containing, 2-5 carboxylic acid functionalities. The substituents monocarboxyalkane, monocarboxyalkene, monocarboxyarylalkane, and monocarboxyarylalkene contain, or originate from reactants containing, only a single carboxylic acid group. Examples of first acylating agents include, but are not limited to, succinic anhydride, 2-(C 1-30 alkyl)succinic anhydride, 2-(C 2-30 alkenyl)succinic anhydride, maleic anhydride, glutaric anhydride, itaconic anhydride, and phthalic anhydride. Examples of second acylating agents include, but are not limited to, acetic anhydride, benzoic anhydride, N,N'-diacetyl-3,5-dimethylpyrazole, N,N'-diacetylimidazole, phenylacetic anhydride, propionic anhydride, and butyric anhydride.
In yet another aspect, the present invention features a process of synthesizing a composition, the process comprising the steps of: reacting chitosan with a weak acid to produce a lower molecular weight polysaccharide; reacting between 1 and 50 percent of the free amines of the lower molecular weight polysaccharide with a first acylating agent, the first acylating agent selected from the group consisting of C 4-C 34 polycarboxyalkane, C 4 -C 34 polycarboxyalkene, C 8 -C 40 polycarboxyarylalkane, C 10 -C 40 polycarboxyarylalkene, or an acylating derivative thereof; reacting between 50 and 100 percent of the free amine of the lower molecular weight polysaccharide with a second acylating agent, the second acylating agent selected from the group consisting of C 2-31 monocarboxyalkane, C 3-31 monocarboxyalkene, C 7-38 monocarboxyarylalkane, C 9-35 monocarboxyarylalkene, or an acylating derivative thereof; neutralizing the acylated lower molecular weight polysaccharide with a base; and mixing the neutralized lower acylated molecular weight polysaccharide with a polypeptide salt, wherein the polypeptide salt comprises at least one ionogenic amine, to form a polypeptide-copolymer ionic conjugate.
The neutralization step preferably renders the lower molecular weight polysaccharide emulsifiable or soluble in water. In preferred embodiments, the base is an inorganic base (e.g., sodium hydroxide). The polypeptide salt is preferably a weak acid salt (e.g., acetate, lactate, or citrate). The ionic conjugate can be isolated by filtering or by centrifuging the resulting mixture.
The conjugates of the invention can easily be made into injectable microspheres or microparticles, and implantable films or rods, without the need to utilize processing that entails multiphase emulsions. Preferably, the microparticles are manufactured by (a) dissolving the composition in an aprotic, water miscible organic solvent; (b) mixing the organic solvent in water; and (c) isolating the microparticles from the water. In preferred embodiments, the organic solvent is chosen from the group of acetone, acetonitrile, tetrahydrofuran, dimethylformamide, and dimethyl ethylene glycol.
Other features and advantages of the present invention will be apparent from the detailed description and from the claims.
DETAILED DESCRIPTION OF THE INVENTION
The synthesis and use of the copolymer and copolymer-polypeptide ionic conjugates of this invention are well within the ability of a person of ordinary skill in the art. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Also, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.
It is believed that one skilled in the art can, based on the description herein, utilize the present invention to its fullest extent. The following specific embodiments are, therefore, to be construed as merely illustrative, and not limitative of the remainder of the disclosure in any way whatsoever.
EXAMPLE 1
Depolymerization of Chitosan
Chitosan (Protan, Inc., Portsmouth, N.H.) is dissolved in aqueous acetic acid by stirring with a mechanical stirrer for one day. Nitrogen gas is bubbled through the solution, while an aqueous solution of sodium nitrite is added. After a half hour, the solution is filtered through a sintered glass funnel, under reduced pressure, to remove insoluble particles which are present in the initial chitosan solution. To the filtered solution is added an aqueous solution of NaOH, and the solution is vigorously stirred in methanol to precipitate the polymer. The resulting precipitate is then filtered and alternately washed five times with water and methanol. The precipitate is then dried in a vacuum oven at 60° C. for two days. The depolymerized chitosan comprises an aldehyde group at one end of the chain. The aldehyde end group may be reduced to a primary hydroxyl group by reaction NaBH 4 . The depolymerized product can be analyzed by gel permeation chromatography (GPC) to determine both its molecular weight and molecular weight distribution (MWD) in comparison to Pullulan reference standards. NMR (nuclear magnetic resonance) and IR (infra-red) studies can be used to determine the amount of N-acetylation on the depolymerized product.
EXAMPLE 2
Partial Succinylation of Depolymerized Chitosan
The depolymerized chitosan from Example 1 is dissolved in 0.1M aqueous acetic acid. To this solution, methanol is added followed by the addition of a solution of succinic anhydride in acetone. The resulting solution is stirred at room temperature for 24 hours. Upon completion of the succinylation, the solution is then precipitated into aqueous acetone. The resulting precipitate is collected by centrifugation and washed five times with methanol. The precipitate is then dissolved in 0.5M KOH and dialyzed against water to a pH of 7. The dialyzed solution is then concentrated under reduced pressure, precipitated in aqueous acetone, and dried in a vacuum oven at 60° C.
To obtain variable levels of succinylation, the extent of the reaction can be monitored as the acylation proceeds by analyzing for number of unacylated amine groups. The number of unacylated amine groups can be determined by quenching a withdrawn sample of the reaction mixture with an amine detecting agent (e.g., flouorescamine). The amount of amine present can be measured spectrophoretically using a standard curve for the copolymer. Additionally, succinic anhydride, thus, can be added successively until the desired acylation percentage is achieved. The exact degree of succinylation of the purified product can be determined using 1 H NMR spectroscopy and conductometric titration.
EXAMPLE 3
Acetylation of the N-succinylated chitosan
The partial succinylated sample from Example 2 is dissolved in 0.1M aqueous acetic acid. To this solution, methanol and acetic anhydride is then added, and the reaction mixture is stirred at room temperature for one day. This solution is then precipitated in aqueous acetone. The resulting precipitate is collected by centrifugation and washed five times with methanol. The precipitate is then dissolved in 0.1N KOH and is dialyzed against water to a pH of 7. The final solution is lyophilized to obtain the final product. The acylation procedure can be measured spectrophoretically as discussed in Example 2, and the exact degree of acylation of the purified product can be determined using 1 H NMR spectroscopy and conductometric titration.
EXAMPLE 4
Preparation of Poly(N-acyl-D-glucosamine)-peptide ionic conjugate
The N-succinylated chitosan potassium salt of Example 3 is dissolved in water. An aqueous solution of the acetate salt of the somatostatin polypeptide analog SOMATULINE™ (D-Nal-c[Cys-Tyr-D-Trp-Lys-Val-Cys]-Thr-NH 2 ; Kinerton, Dublin, Ireland) is added to the stirred polymer solution. A precipitate forms and is filtered and dried in a vacuum oven at 40° C.
The polypeptide content of the resulting ionic conjugate can be determined by the difference between the amount of initial peptide added and the amount of free residual peptide contained in the filtrate and rinse solution. The peptide content of the resulting ionic conjugate can be determined by comparing the carbon/nitrogen ratio of the initial N-succinylated chitosan with that of the resulting ionic conjugate. GPC analysis can be used to determine molecular weight and MWD, differential scanning calorimetry (DSC) to determine thermal properties and NMR and IR for chemical identity.
Other Embodiments
It is to be understood that while the invention has been described in conjunction with the detailed description thereof, that the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the claims.
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A copolymer comprising an N-acylated derivative, and a composition comprising said copolymer and a polypeptide, said polypeptide comprising at least one effective ionogenic amine, wherein at least 50 percent, by weight, of said polypeptide present in said composition is ionically bound to said polymer.
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SCOPE OF INVENTION
[0001] Plaster for topical use having an analgesic activity and being able to re-absorb haematomas, containing diclofenac in association with heparin or a heparinoid.
STATE OF THE ART
[0002] Known and available on the market are creams for topical use with a base of heparinoids, possibly in association with hyaluronidase, for re-absorption of haematomas and ecchymoses.
[0003] Though remarkably effective, these creams involve a number of drawbacks. In fact, they do not present a more specific analgesic activity, which would be particularly necessary in the case of serious ecchymoses.
[0004] In addition, the creams, the application of which involves first spreading the cream, and subsequently rubbing or gentle massaging on the area affected, do not enable uniform dosing of the active principle from one application to the next.
[0005] In addition, with this type of formulation it is not possible to control in any way the release of active principle; consequently, these formulations must be applied on the area affected at least twice a day, with considerable inconvenience, in that they necessarily leave greasy residue on the skin.
[0006] In the European Patent Application EP-A-621263, a plaster is described containing as active principle only diclofenac in the form of a pharmaceutically acceptable salt with an alicyclic organic base.
[0007] This type of plaster represents an alternative system to oral administration of diclofenac, and administration which, as is known, presents considerable undesirable effects at the gastric level.
SUMMARY OF INVENTION
[0008] The applicant has now discovered a plaster containing heparin or heparinoids in association with diclofenac or one of its salts that is pharmaceutically acceptable for topical use, which does not present the drawbacks of the cream compositions that are known for the same type of use.
[0009] This plaster in particular comprises:
[0010] a) a substrate layer;
[0011] b) an adhesive layer in the form of a hydrogel matrix in which the above-mentioned active principles are dispersed;
[0012] c) a protective film which can be removed at the moment of use.
DETAILED DESCRIPTION OF INVENTION
[0013] In the plaster according to the present invention, diclofenac is generally present in the form of a pharmaceutically acceptable salt, and preferably it is a salt with a heterocyclic amine of general formula:
[0014] where m is 0 or1.
[0015] According to a particularly preferred embodiment, the heterocyclic amine is N-hydroxyethyl pyrrolidine (epolamine).
[0016] The diclofenac salt is contained in the plaster according to the present invention in concentrations generally ranging from 0.1 to 5 wt %, preferably in concentrations of between 0.3 and 3 wt % with respect to the total weight of the composition used for the preparation of the hydrogel matrix.
[0017] According to a particularly preferred embodiment, the concentration of the diclofenac salt is 1.3 wt % with respect to the total weight of the composition used for the preparation of the hydrogel matrix.
[0018] When the plaster according to the present invention contains a heparinoid, the latter preferably presents a molecular weight of between 5,000 and 30,000 DA.
[0019] The heparin or heparinoid is present in concentrations such that its total quantity in the plaster is between 0.05 and 1%, which corresponds respectively to a concentration range of between 1,400 and 28,000 IU/plaster (100-2,000 IU/g matrix).
[0020] According to a particularly preferred embodiment, heparin is contained in concentrations such that the corresponding content is 5600 IU per plaster.
[0021] It is advisable that the composition used for preparing the hydrogel matrix should present pH values of between 7.2 and 9, preferably of between 7.5 and 8.5. At pH values lower than 7.2, the diclofenac crystals that are insoluble in water precipitate; values higher than 9 may cause irritation of the skin. To adjust the pH of the hydrogel composition, any organic or inorganic acid, or any organic or inorganic base may be used, without any particular limitation. The concentration of the above-mentioned acid or base is not critical either and may vary according to the pH value that the hydrogel composition reaches.
[0022] In addition to the aforementioned active principles, the hydrogel matrix further contains thickening agents, wetting agents, fillers, preservatives, cross-linking agents, surfactants, stabilizers, etc.
[0023] Preferably, the composition used for the preparation of the hydrogel matrix contains as thickening agents the following: polyacrylic acid, sodium polyacrylate, sodium carboxymethyl cellulose, polyvinyl alcohol, polyvinyl pyrrolidone, gelatine or corresponding mixtures. The concentration of the above additives is generally between 3 and 30 wt %, preferably between 5 and 20 wt %. If the concentration is lower than 3 wt %, the viscosity of the composition is too low, so that the composition comes out of the plaster and remains on the skin once the plaster is applied; on the other hand, if the concentration is too high, it is not very workable. According to a particularly preferred embodiment, the thickening agents are a mixture consisting of the following: gelatine, polyvinyl pyrrolidone, sodium polyacrylate, and sodium carboxymethyl cellulose in a total concentration of 9 wt % with respect to the total weight of the hydrogel matrix.
[0024] The hydrogel matrix of the plaster according to the present invention preferably comprises at least one wetting agent chosen from among glycerol, propylene glycol, polyethylene glycol, 1,3-butanediol, and an aqueous solution of D-sorbitol, preferably in a concentration of 70 wt %.
[0025] The concentration of the said wetting agents in the composition used for the preparation of the hydrogel matrix according to the present invention is between 5 and 70 wt %, preferably between 10 and 60 wt % with respect to the total weight of the composition used for the preparation of the hydrogel matrix .
[0026] If the quantity of wetting agent is lower than 5%, the wetting effect is not sufficient and the composition dries quickly; if, instead, the quantity of wetting agent is higher than 70%, mixing of the components is difficult.
[0027] The cross-linking agent is preferably an aluminium or calcium compound present in the composition used for the preparation of the hydrogel matrix in a concentration of between 0.01 and 3.0 wt %. If the quantity of this additive is lower 5 than 0.01 wt %, cross-linking is insufficient, so that the resistance to heat of the hydrogel matrix is reduced; consequently, two drawbacks may occur, either during storage or during application: during storage, the composition is too fluid and comes out of the plaster in the sterile container of the latter; when the plaster is applied, the composition leaves a residue on the skin. When the concentration of the cross-linking agent is higher than 3%, the rate of cross-linking is too high and consequently the viscosity of the composition used for the preparation of hydrogel matrix increases, so that the corresponding workability decreases.
[0028] As a filler, one of the following, for instance, may be used: kaolin, titanium dioxide, bentonite, or mixtures of the said compounds.
[0029] As a preservative, the hydrogel matrix that is the subject of the present invention may contain either preservatives of a conventional type, such as the esters of para-alkyloxy benzoic acid, for example Nipagin and Nipasol, or sorbic acid. The hydrogel matrix may possibly contain a surfactant, such as a polyoxyethylene sorbitan ester (Tween 80) and a stabilizer, such as sodium ethylenediamine tetraacetate.
[0030] As far as the substrate layer is concerned, any material usually employed for this purpose may be used, such as fabric, non-woven fabric, paper, plastic film and corresponding laminates.
[0031] As regards the removable protective film, this may be of a conventional type, for instance, siliconized paper, or may be made of a plastic material, such as polyethylene, polyethylene terephthalate, or polyvinyl chloride.
[0032] The present plaster is prepared according to conventional methods which, in particular, envisage the following fundamental stages:
[0033] mixing of the various components of the composition used for the preparation of the hydrogel matrix,
[0034] co-extrusion of the hydrogel matrix between the substrate layer and the removable protective film.
[0035] The mixing phase is in particular conducted in the following stages:
[0036] 1-A) mixing of one part of water with the filler and with part both of the cross-linking agent and of the thickening agent;
[0037] 1-B) subsequent addition to the mixture obtained in stage (1-A) of further thickening agents;
[0038] 1-C) addition to the mixture obtained in stage (1-B) of preservatives, a stabilizer, a pH adjuster, as well as of the remaining part of the cross-linking agent and thickening and wetting agents;
[0039] 1-D) addition to the mixture obtained in stage (1-C) of the pharmaceutically acceptable diclofenac salt;
[0040] 1-E) addition to the mixture obtained in stage (1-D) of the heparin or heparinoid.
[0041] To provide a non-limiting illustration, an example is given of preparation of the hydrogel matrix used as adhesive layer of the plaster according to the present invention.
COMPONENTS % (p/p) DIEP 1.3 Sodium heparin 198 IU/mg 0.202 (5600 IU) per plaster Gelatine 2.0 Polyvinyl pyrrolidone 2.0 Nipagin 0.1 Nipasol 0.05 Propylene glycol 3.0 Tween 80 0.2 Kaolin 3.0 Titanium dioxide 0.5 Sorbitol 40.0 EDTA NA 0.12 tartaric acid 0.5 Aluminium glycinate 0.3 Sodium polyacrylate 4.0 Sodium carboxymethyl cellulose 3.0 Butylene glycol 10.0 Water 29.73
[0042] One part of water, kaolin, titanium dioxide and 70% sorbitol is added; to this is added, in the form of an aqueous solution, one half of the quantity of dihydroxy aluminium glycinate, sodium polyacrylate, sodium carboxymethyl cellulose, and 1,3-butanediol. Everything is mixed by stirring.
[0043] To the mixture thus obtained is added an aqueous mixture of gelatine and polyvinyl pyrrolidone, an aqueous solution containing Nipagin, Nipasol, NaEDTA, tartaric acid, and finally an aqueous solution consisting of the remaining part of aluminium glycinate, 1,3-butanediol, sodium carboxymethyl cellulose and sodium polyacrylate, and subsequently the product is mixed under stirring.
[0044] To the mixture thus obtained, finally the active principles are added; first, a solution is added of the diclofenac salt with N-hydroxyethyl pyrrolidine (DIEP), and finally a heparin aqueous solution, to obtain the composition given in the table above, which is subsequently extruded.
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Plaster for topical use having an analgesic activity and at the same time being able to re-absorb haematomas, comprising:
a substrate layer;
an adhesive layer in the form of a hydrogel matrix containing a pharmaceutically acceptable diclofenac salt, heparin or a heparinoid;
a protective film which can be removed at the moment of use.
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FIELD OF THE INVENTION
This invention relates to a fishing rod rest and more particularly to a forearm rest or supporting device having a rod engaging portion for attachment to the handle of the fishing rod and having a laterally extending portion projecting normal to the longitudinal axis of the rod for accommodating the forearm of an angler to assist the angler in holding the fishing rod when he is awaiting a bite or when he is reeling in the fishing line and for readily clearing the forearm of the angler when he is casting the lure or bait.
BACKGROUND OF THE INVENTION
In the sport of fishing, it is normal for a fisherman to spend endless hours in attempting to catch the sought after aquatic craniate vertebrate. After several hours of casting, trolling and just plain fishing, the fisherman becomes quite weary in holding the fishing rod with only one hand, and he usually seeks relief by holding the rod with both hands, or alternatively, he lays the rod down or mounts it in a holder planted in the ground or fixed to the side or back of a boat. A great amount of stress and strain is placed on the hand, wrist and arm of the fisherman as he manipulates the fishing rod in his endeavor to catch a prize fish or even to snare a tidbit panfish. Also, it has been found that people with arthritis or the like as well as handicapped individuals experience physical difficulty, pain and/or mental anguish in their attempts to enjoy the sport of fishing. Previous mechanisms and devices for relieving this agonizing discomfort and weary feeling which every fisherman has experienced at one time or another have not been totally successful for one reason or another. That is, none of these prior art devices were wholly satisfactory since they were possessed of one or more shortcomings. For example, while various braces, holders and supports have been proposed in the past, many of the previous devices hindered and interfered with the fisherman's ability to spin and cast while other braces, holders and supports were awkwardly located and resulted in the unnatural positioning of the hand, wrist and arm of the fisherman. In either case, many anglers readily recognized the deficiencies and would not even entertain purchasing such previous devices, or if purchased, the fisherman soon became disenchanted and quickly discarded the prior art forearm aiding devices. In order to win the wholehearted acceptance of the many fisherman, a rod supporting device must not restrict or interfere with the manuverability of the angler to cast out his lure or bait and also must allow the fisherman to hold his rod in a normal and comfortable position. Generally, a fisherman holds the handle of a spin casting type of rod in the palm of his hand while biding his time and waiting for a bite or leisurely manipulates the tip of the rod as he winds in the line. In this rod holding position, the forearm is generally slightly off to one side of the rod forming an acute angle therebetween. Anterior types of fishing rod supporting devices, such as, those shown and disclosed in U.S. Pat. Nos. 2,244,408; 3,367,056 and 4,014,129 and French Pat. No. 1,553,055 employed U-shaped cradle members which were directly mounted to the top of the handle and in-line with the longitudinal axis of the fishing rod or pole. Such previous arrangements were not only uncomfortable for the fisherman to hold the rod due to the unnatural positioning of his arm which caused and placed undue stress and strain on the forearm and bicep muscles. In many cases, the fisherman would suffer from cramps or muscular constrictions and at the very least he would experience tension and exertion which soon made him weary and tired. In addition, such previous in-line cradle supports also interfered with the ability of the fisherman to cast his lure or bait since the fisherman's forearm had the tendency to strike and hit the cradle portion during the casting motion. Thus, it will be appreciated that an acceptable and successful forearm rest for a fishing rod must allow the angler to assume a natural and comfortable gripping position yet must not impede with the free casting ability of the angler.
OBJECTS OF THE INVENTION
Accordingly, it is an object of this invention to provide a new and improved forearm rest for a fishing rod.
Another object of this invention is to provide a unique fishing rod arm rest which naturally supports the forearm of a fisherman and which unrestrictively allows the fisherman to cast his line.
A further object of this invention is to provide a novel forearm supporting device for a spinning rod which relieves the stress and strain on the arm of an angler.
Yet another object of this invention is to provide an improved forearm supporting device for assisting the fisherman in retrieving his lure and in landing his catch.
Yet a further object of this invention is to provide a new supporting device for a fishing rod which allows an angler to fish with less fatigue and in greater comfort.
Still another object of this invention is to provide an arm rest which is attached to the handle of a spinning rod and which is adapted to readily accommodate the forearm of the angler.
Still a further object of this invention is to provide a rest for aiding an angler in holding a fishing rod having a first means for connection to the handle of the fishing rod, and a second means adapted to extend laterally to one side of the handle of the fishing rod, the second means being arcuately shaped to fit the forearm of the angler wherein the forearm forms an oblique angle with the longitudinal axis of the fishing rod for preventing stress and strain of the arm of the angler yet permitting unimpeded movement during casting.
An additional object of this invention is to provide an improved forearm rest for a fishing rod which is economical in cost, simple in construction, quick to install, durable in service, facile to use and easy to operate.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided a unique forearm supporting device for aiding a fisherman to hold his fishing rod during trolling, still fishing and retrieving and for freely allowing the fisherman to cast his lure or bait without interference. The forearm supporting device includes a long narrow piece of material having a handle attachment portion and a forearm accommodating portion. The long narrow piece of material may be a strip of metal which may be bent to the desired shape by a suitable bending machine or metal forming device or jig. The forearm accommodating portion preferably takes the form of an arcuate or U-shaped section which extends outwardly and normal to the longitudinal axis of the fishing rod. In one embodiment, the handle attachment portion takes the form of a circular band or ring which encompasses the handle of the fishing rod. After proper positioning, the supporting device is clamped onto the handle of the fishing rod by tightening a fastener, such as, a suitable self-tapping screw, which causes the compression of the circular band or ring. In another embodiment, the handle attachment portion takes the form of a dimpled or tongued rectangular spring tang or tab which fits and plugs into a selected one of a plurality of matching notches or holes formed along the length of the handle of the fishing rod. In practice, the fisherman normally holds the handle of the fishing rod in the palm of his hand and has the underside of his forearm resting in the arcuate or U-shaped section. Thus, the fisherman assumes a natural and comfortable position with his forearm making a slight or acute angle with respect to the longitudinal axis of the fishing rod. Further, the supporting device does not in anyway interfere with the ability of the fisherman to cast his bait or lure since the supporting device extends outwardly away from the forearm of the fisherman. Thus, during casting or throwing of the line, the forearm of the fisherman is allowed to clear and freely pass by the inner side of the handle and supporting device without interference.
DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of this invention will become more clearly apparent from the following detailed description when read in conjunction with the accompanying drawing wherein:
FIG. 1 is a perspective view of a spinning type of fishing rod and reel having a first forearm rest or supporting device constructed in accordance with the present invention.
FIG. 2 is a view in end elevation of the forearm rest or supporting device shown in FIG. 1.
FIG. 3 is a perspective view of a second forearm rest or supporting device for a spinning type of fishing rod which is shown phantom.
FIGS. 4, 5 and 6 are fragmentary diagrammatic views illustrating the use of the present invention during different stages of angling, such as, casting, trolling, still fishing or retrieving.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings and in particular to FIGS. 1 and 2, there is shown one embodiment of the present invention. In viewing FIG. 1, it will be seen that the forearm rest or supporting device which is generally characterized by numeral 1 is combined with a spinning type of fishing rod 2. The spinning rod 2 includes an elongated flexible shaft 3 and a hand gripping portion or handle 4. A spinning reel 5 includes a T-shaped extension or bracket 6 which is securely mounted to the forward end of the handle 4 by a pair of conventional fixed and movable clamping rings 7 and 8, respectively. As shown in FIG. 1, the supporting rest 1 is situated and mounted near the rearward end of the handle 4 of the spinning rod 2. In practice, the forearm rest 1 is formed from a single piece of sheet metal, such as, a long narrow band or strip of sheet aluminum. Actually, the rest is made of a 1/16 inch strip of 5052-H32 sheet aluminum having a width of approximately one inch and having a length of approximately seven inches.
The flat aluminum strip is placed into a metal bending machine or suitable metal forming device which forms an arcuate or U-shaped portion 10 and circular band or ring-like portion 11. The radius of curvature of the arcuate portion 10 is preferably large enough to readily accommodate the forearm of an angler or fisherman with ease and comfort. Similarly, the diameter of the ring portion 11 is selected and chosen to fit over the cork or rubber covered handles or even the wooden handles of most commercially available spinning rods. As shown in FIG. 2, the terminal portion 12 of the ring 11 is arranged to be substantially paralled to the curvature of portion 10. A hole is then drilled through both the arcuate portion 10 and the terminal portion 12. The hole in portion 10 is countersunk to accommodate the conical shape of a self-tapping flat head screw 13.
It will be seen that the forearm rest 1 is fitted into the handle 4 and is suitably moved and shifted along the length thereof to the desired and appropriate position. The forearm rest 1 may be rotated about the longitudinal axis of the rod 2 and is located substantially 90 degrees in relationship to the reel bracket 6. After the rest 1 is suitably positioned, the self-tapping crew 13 is appropriately turned and tightened with a coin or screwdriver to securely attach the forearm rest 1 in place on the handle 4.
In viewing FIG. 3, it will be noted that there is shown another embodiment of the present invention. The forearm rest or supporting device is generally characterized by numeral 1'. The forearm rest or support 1' is also preferably fabricated from 5052-H32 sheet aluminum which is relatively ductile for being readily bent and is sufficiently rigid after bending to maintain its shape even under abnormal conditions. As shown, the forearm rest 1' is bent and shaped to form an arcuate forearm receiving portion 10'. It will be noted that the handle attaching portion consists of a rectangular tang or tab 11' having a dimple or spring tongue 13' punched out of the sheet aluminum. It will be observed that a plurality of rectangular slots or openings 14 are formed along the length of the handle 4' of the spinning rod 2'. Thus, the tang or tab 11' may be inserted and snapped into a selected one of the plurality of slots 14 by the fisherman as desired. The dimple or spring tongue 13' locks the rest 1' in the desired position.
It wil be appreciated that the two illustrated embodiments are adapted for right-handed anglers or fishermen since the rests 1 and 1' extend outwardly to the right side of the rod as viewed in the drawing. Thus, the underside at the right forearm of the fisherman is arranged to comfortably rest on the upper surface of the arcuate portion 10, 10' when still fishing, trolling or retrieving. Thus, the engagement of the forearm with the supporting device or rest and the gripping of the handle by the fingers or palm of the hand of the fisherman provides a two point holding or supporting arrangement for more readily retaining the fishing rod as shown in FIG. 6. In viewing FIG. 6, it will be seen that the arm of the angler assumes a natural position and forms an oblique or acute angle φ with respect to the longitudinal axis of the fishing rod 2. Thus, the angler may fish in comfort and with for many many hours since the stress and strain on his fingers, hand, wrist and arm is completely removed or relieved by the supporting action of the forearm rest 1.
Further, the forearm rest or supporting device 1, 1' does not impede or interfere with the casting of the fisherman. As shown in FIGS. 4 and 5, the arm of the angler is slightly disposed to the left of the handle 4 during the normal casting of the lure or baited hook. Thus, since the entire forearm rest 1 extends outwardly or away from the handle of the fishing rod 2, there will be no obstruction or impediment in the way of the arm of the angler when he is in the act of casting or attempting to cast as shown in FIG. 5. Accordingly, the unique forearm rest of the present invention aids the fisherman in holding the fishing rod for more enjoyable and relaxed fishing and yet allows him to freely cast without restriction.
Accordingly, the present invention results in an improved and advantageous benefit for anglers of all ages at a nominal cost and with a minimum effort. It will be appreciated that the forearm rest is adaptable to both right-handed and left-handed anglers. The forearm rest 1 may be removed from handle 4 and rotated or turned about 180 degrees and repositioned on handle 4 to accommodate a left-handed fisherman. Similarly, forearm rest of supporting device 1' may be positioned into one of a plurality of slots which may be formed in the left side of the handle 4' to accommodate a left-handed fisherman.
It is understood that certain changes and modifications may be made to the presently described forearm rest without departing from the spirit and scope of the invention. For example, a different sheet metal, such as, steel, brass, copper or the like, may be used in place of the sheet aluminum. Further, the rest or supporting device may be cast or extruded from metal or even plastic with similar results. In addition, the length, width and thickness may be varied in accordance with a number of variables, such as, the size, weight and height of the angler, the type of material of the rest, the type and model of the fishing rod, etc. Also, the radius of curvature of portion 10 may be varied and the handle attachment portion 11, 11' may be changed as desired.
It will be apparent to those skilled in the art that other changes, variations and alterations of the supporting device shown and described may be made without departing from the spirit and essence of the invention, and therefore it is understood and intended that all equivalents and incidental modifications are herein meant to be covered by the appended claims.
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A forearm rest for assisting an angler in holding a spinning type of fishing rod and for allowing the angler to freely cast without hinderance. The forearm rest includes a long narrow arcuate portion extending outwardly from the handle for accommodating the forearm of the angler and includes a handle attaching portion for secure connection to a desired position along the handle of the fishing rod.
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FIELD OF THE INVENTION
[0001] This invention relates to a set of brackets for constructing a wooden gate.
BACKGROUND OF THE INVENTION
[0002] Corner gate brackets can be used to frame right angle joints between structural members of a gate at each of four corners. Such gate brackets are meant to provide a reliable guide for the positioning of the structural members to assist the do-it-yourself handy man. In addition, corner gate brackets are meant to minimize or eliminate the distortion of the gate structure over time.
[0003] Gate brackets are typically made of metal so as to resist bending and to ensure a rigid structure. Typically, a gate bracket comprises elongate flat metal members arranged in perpendicular relationship so as to guide the formation of a right angle between the pieces of structural lumber which are made to abut the elongate members. An example of such a system is disclosed in Boroviak, U.S. Pat. No. 6,896,244.
[0004] Parallel elongate flat metal members may be provided in a spaced relationship for bracketing structural lumber on two opposed sides and to provide a perpendicular arrangement of such elongate members. Such a system is disclosed in Cosgrove, U.S. Design Patent No. D410,835. In Cosgrove, each pair of parallel elongate flat metal members form a U-shape and the two U-shaped pairs are welded together to form the overall bracket.
[0005] To provide structural rigidity for gate brackets, typically either a brace member is provided, as in Boroviak, or relatively thick metal members are provided, as in Cosgrove. In Boroviak, the diagonal brace member is welded to each of the perpendicular elongate metal members, which are in turn welded together at the intersection.
[0006] It is an object of the present invention to provide a structural gate bracket that serves to effectively frame a right angle between structural pieces, such as 2×4 pieces of lumber, while maintaining the structural relationship of the joint, over time, and at the same time not providing undue weight to the gate bracket, avoiding overly thick metal elements or excessive welding.
[0007] This and other objects of the invention will be better understood with reference to the detailed description of the invention which follows.
SUMMARY OF THE INVENTION
[0008] According to the invention, there is provided a web extending in a plane. A first pair of perpendicular elongate portions are provided normal to the plane of the web, preferably along two edges of the web. A second pair of perpendicular elongate portions are provided normal to the plane of the web in spaced parallel relationship to the first pair.
[0009] In another aspect of the invention, each pair of elongate portions comprises flanges of said web.
[0010] In a further aspect, an opening is provided in said web member between the first and second pairs of elongate portions.
[0011] In a further aspect, the opening extends between a first pair of parallel first and second members and between a second pair of parallel first and second members thereby defining a substantially L-shaped opening.
[0012] In another aspect, the invention comprises a web extending in perpendicular directions in a plane, said web including a first flange extending normal to said plane parallel to a first one of said directions, a second flange extending normal to said plane parallel to a second one of said directions in an end-to-end perpendicular, abutting relationship to said first flange. The web has an outer perimeter, an opening extending in generally perpendicular directions within said perimeter, a third flange normal to said plane along an edge of said opening and in spaced relationship to said first flange and a fourth flange normal to said plane along an edge of said opening and in spaced relationship to said second flange.
[0013] In another aspect, the invention comprises a method of forming a gate bracket comprising:
providing a web extending generally in perpendicular directions within a plane and having an opening within the perimeter thereof, said opening extending generally in said perpendicular directions; bending one edge of said web to provide a first flange normal to said plane; bending a second edge of said web to provide a second flange normal to said plane and abutting said first flange in a perpendicular relationship; bending a portion of said web that is adjacent to an edge of said opening to form a third flange normal to said plane; bending a portion of said web that is adjacent to an edge of said opening to provide a fourth flange normal to said plane and in perpendicular abutting relationship to said third flange.
[0019] The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the invention and to the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention will be described by reference to the detailed description of the invention and to the drawings thereof in which:
[0021] FIG. 1 is a front perspective view of a first embodiment of the invention;
[0022] FIG. 2 is a rear perspective view of the first embodiment of the invention;
[0023] FIG. 3 is a plan view of the first embodiment;
[0024] FIG. 4 is a plan view of a web member, prior to bending, according to the method of the first embodiment;
[0025] FIG. 5 is a front perspective view of a web member of FIG. 4 after the bending of the first and second flanges according to the method of the first embodiment;
[0026] FIG. 6 is a rear perspective view of a second embodiment of the invention; and
[0027] FIG. 7 is a front perspective view of a third embodiment of the invention;
[0028] FIG. 8 is a front perspective view of a fourth embodiment of the invention; and
[0029] FIG. 9 is a plan view of the fourth embodiment of the invention, prior to bending.
DETAILED DESCRIPTION OF THE INVENTION
[0030] Throughout the following description specific details are set out to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the present invention. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.
[0031] Referring to FIGS. 1 , 2 and 3 the gate bracket of the first embodiment 10 includes a web 12 extending within a plane generally along two perpendicular directions 14 and 16 in a generally L-shaped configuration.
[0032] Web 12 has a generally L-shaped opening 18 that extends in perpendicular directions parallel to directions 14 and 16 . Opening 18 is spaced inwardly from the perimeter 20 of the web 12 .
[0033] A first flange 22 extends normal to the plane of the web 12 along a perimetral edge 24 of web 12 , parallel to direction 14 . A second flange 26 extends normal to the plane of the web 12 along a perimetral edge 28 of web 12 , parallel to direction 16 . First 22 and second 26 flanges are in abutting perpendicular relationship to one another.
[0034] A third flange 30 extends normal to the plane of the web 12 along an edge 32 of opening 18 . Third flange 30 extends parallel to first flange 22 and in spaced relationship therewith.
[0035] A fourth flange 34 extends normal to the plane of the web 12 along an edge 36 of opening 18 . Third 30 and fourth 34 flanges are in abutting perpendicular relationship to one another.
[0036] The spacing between first 22 and third 30 flanges is selected so as to correspond to the dimensions of structural pieces (such as lumber, plastic or metal), to be used in the gate system, as is the spacing between second 26 and fourth 34 flanges.
[0037] One end of each of the third and fourth flanges may optionally be further bent away from opening 18 as at 38 , 40 in order to provide additional structure rigidity to the flanges.
[0038] A hinge 42 may be provided on selected brackets according to whether the bracket will be used on the hinge side of the gate to be constructed.
[0039] One advantage of the first embodiment of the invention is that the entire structure, save for the attachment of a hinge, may be formed from a single flat sheet of materials, as will be described by reference to FIGS. 4 and 5 .
[0040] There is first provided a web 12 as shown in FIG. 4 that extends generally in two perpendicular directions 14 and 16 . Web 12 is cut at 17 , 19 , 21 and 23 , with cut 19 being parallel to direction 14 and cut 21 being parallel to direction 16 . Each cut 17 , 19 , 21 , 23 is spaced inwardly from the edges of web 12 . A gap 15 is provided at the juncture cut lines 19 and 21 .
[0041] An elongated rectangular portion 30 is bent from the plane of the web so as to be normal to it and an elongated rectangular portion 34 is bent from the plane of the web so as to be normal to it to form flanges 30 and 34 .
[0042] Short end portions 29 , 31 of flanges 30 , 34 may then be bent along lines 33 , 35 so as to be normal to flanges 30 , 34 to provide structural rigidity to flanges 30 , 34 .
[0043] An elongated rectangular portion 22 along edge 25 of web 12 is bent so as to form a flange 22 that is normal to the plane of the web 12 . An elongated rectangular portion 26 along edge 27 of web 12 is bent so as to form a flange 26 that is normal to the plane of the web 12 . Once bent, flanges 22 and 26 are in abutting perpendicular relationship and flanges 30 , 34 are in abutting perpendicular relationship, as seen in FIGS. 1 and 2 .
[0044] As shown in a second embodiment 60 illustrated in FIG. 6 , the shape of the web 12 may be altered in area 68 , for example to increase rigidity, and the hinge 42 may not be provided on selected brackets.
[0045] As shown in the third embodiment 70 shown in FIG. 7 , alternate embodiments of the invention do not require web 12 to extend into area 68 beyond flanges 30 and 40 . Optional piece 76 could be welded between flanges 30 and 40 to assist with the structural integrity of the bracket.
[0046] A fourth embodiment 80 is shown in FIG. 8 in which a straight edge 86 can brace the portion between perpendicular structural members on a corner. Flanges 82 and 84 can be attached to the outside edges of structural members while flanges 88 and 90 can be attached to the inside edges. Flange 82 together with flange 88 and flange 84 together with flange 90 can firmly hold the structural members (such as 2×4 lumber pieces) of the corner of a gate in place. When folded in position, flanges 88 and 90 leave openings 92 and 94 in embodiment 80 . The edge along 86 can be reinforced by folding the edge over itself, as shown in FIGS. 8 and 9 . Further, a hole 96 may be provided, for example to reduce the overall material used and the weight of the embodiment. For versions of embodiment 80 used on the side of the gate to which a hinge should be attached, a hinge may be attached to one of flanges 82 and 84 , and preferably to flange 84 . As shown in FIG. 9 with reference to planar layout 98 , embodiment 80 can be made from a flat piece of unitary material, such as sheet metal.
[0047] In a method of assembly of a gate or door, four brackets as described above, may be used in the construction of a gate. Two brackets placed on adjacent corners may have hinges, whereas the two other brackets may not have hinges. Structural pieces, such as lumber, plastic or metal members may be used in the assembly of the gate. Typically four structural pieces of lumber (or equivalent) will be used to create a gate frame in a square or rectangular formation. Gate face structural members, such as 2×4 pieces of lumber, can then be secured to the gate frame to complete the gate. As understood in the art, the face structural members could be attached to one side of the gate frame, on both sides, or having face structural members in an alternating pattern with structural members secured to opposing sides of the gate frame.
[0048] Many other variations or additional features can be practiced in accordance with this invention. For example, a structural brace 66 could be added between flanges 30 and 34 . The structural brace would help maintain the structural integrity of the corner of the gate. The structural brace could be placed at any suitable angle, such as 45 degrees from each of flanges 30 and 34 .
[0049] Portions 64 of web 12 could be punched out, cut out, or otherwise removed from the structure without departing from the scope of the invention. Cutting out portions 64 of web 12 could be of any desired shape and location and would reduce the amount of material, such as metal, and reduce the weight of the gate bracket.
[0050] In certain embodiments, reinforcing lines 62 could be used to add structural integrity to the metal. Reinforcing lines 62 could be depressions formed on one side of the metal, with a corresponding protrusion on the opposite side of the metal. To maximize effectiveness of the reinforcing lines 62 , the lines may be linear. Reinforcing lines 62 could be added to web 12 or flanges 30 and 31 .
[0051] It will be appreciated by those skilled in the art that the first and second embodiments have been described above in some detail but that certain modifications may be practiced without departing from the principles of the invention.
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A gate bracket is formed of a planar web in which two rectangular portions along two edges of the web are bent to define a first pair of perpendicular flanges, and two other rectangular portions are bent from an inner portion of the web to form a second pair of perpendicular flanges. The flanges of the first pair are spaced from the flanges of the second pair by a distance corresponding to the dimensions of the structural members used to construct the gate. The invention provides a rigid bracket of simpler and lighter construction than prior art brackets.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a data input circuit for a semiconductor memory device, and more particularly, to a data input circuit including an echo clock generator which reduces the clock cycle time in a synchronous semiconductor memory device. When this circuit is used in a synchronous dynamic random access memory (SDRAM), it may be called a Double Data Rate SDRAM (DDR-SDRAM). The circuit also may be used in other types of DRAM, and in other memory interfaces and memory devices such as static RAM (SRAM), flash memory, ferro-electric RAM (FRAM), and the like.
2. Description of the Related Art
In general, a computer system includes a central processing unit (CPU) for executing instructions for a given job, and a main memory for storing data and programs required by the CPU. Thus, in order to improve the performance of the computer system, it is necessary to improve the operating speed of the CPU and reduce the access time to the main memory. Accordingly, a double data rate synchronous dynamic random access memory (DDR-SDRAM) has been developed, which operates under the control of a system clock so that the main memory may be accessed very quickly.
FIG. 1 is a block diagram of a conventional data input/output circuit, in which data from an external source is input to a memory device via a data input buffer.
FIG. 2 is a diagram showing the various times that limit the clock cycle time t CC in a conventional data input circuit. Here, CLK -- SYS represents the waveform of a system clock, CLK -- CNTR represents the waveform of the system clock input to a memory controller, CLK -- DRAM represents the waveform of the system clock input to a DRAM, DATA -- DRAM represents data output from the DRAM, and DATA -- CNTR represents data output by the controller. CLK -- CNTR and CLK -- DRAM are the same as the system clock CLK -- SYS, but they are skewed because of the physical distances between the source that generates CLK -- SYS, the controller, and the DRAM.
Generally, the operation of the SDRAM is controlled in response to a clock signal generated by a system clock. Referring to FIG. 2, it may be seen that the clock cycle time t CC of the SDRAM is restricted by various factors. The clock cycle time t CC is determined and limited by the sum of the following times: the time difference t SW between the minimum time required for a writing operation of the memory and a clock cycle of the data input to a data controller, the time t AC from the clock synchronization to a data output, the time t FL required for transferring data from a memory to a controller, and a data set-up time t SS by the controller.
Therefore, t CC imposes a limitation on the system, in that t CC must be greater than the sum of t SW , t AC , t FL , and t SS . These limitations make it difficult to implement a SDRAM having a frequency of 300 MHz or greater using a conventional data input circuit.
SUMMARY OF THE INVENTION
To solve the above problem, it is an object of the present invention to provide a data input circuit for a synchronous semiconductor memory device that is capable of reducing the clock cycle time.
Accordingly, to achieve the above object, there is provided an input circuit for a semiconductor memory device comprising: a data input buffer receiving input data and outputting buffered input data; an echo clock generator receiving a data clock at a frequency and sequentially generating an echo clock at twice the frequency; and an input data transmission circuit receiving the buffered input data and the echo clock and generating clocked input data synchronously with the echo clock. The echo clock generator further receives an enable signal for enabling the generation of the echo clock; and a burst length count for determining a number of echo clocks sequentially generated by the echo clock generator, and the echo clock generator further comprises: an echo clock buffer for generating a buffered data clock signal in response to the data clock and the enable signal; a burst length counter, receiving the burst length count and the echo clock, for counting the number of sequential echo clocks and generating a burst end signal when the number of sequential echo clocks corresponds to the burst length count; a burst clock generator, responsive to the buffered data clock signal and the burst end signal, for generating the number of sequential echo clocks corresponding to the burst length count; and a reset circuit for resetting the burst length counter when the number of sequential echo clocks corresponding to the burst length count has been generated. The burst clock generator comprises: a latch circuit having inputs coupled to the buffered data clock signal and the burst end signal and an output that generates a pulse enable signal; and an echo pulse generator for generating the number of sequential echo clocks corresponding to the burst length count in response to the buffered data clock signal and the pulse enable signal. The echo clock buffer comprises: a lower current mirror circuit for detecting the voltage of the data clock based on a lower reference voltage, and producing a first output signal; an upper current mirror circuit for detecting the voltage of the data clock based on an upper reference voltage which is higher than the lower reference voltage, and producing a second output signal; and a buffer latch circuit coupled to the first and second output signals, for generating the buffered data clock signal, wherein the buffered data clock signal is transited when the voltage of the data clock decreases to below the lower reference voltage or increases to above the upper reference voltage. The burst length counter comprises: a counting signal generator circuit for counting the echo clock and generating a plurality of counting signals representative of the number of sequential echo clocks; and a burst length signal generator circuit receiving the counting signals and the burst length count, and outputting the burst end signal when the number of sequential echo clocks corresponds to the burst length count. The latch circuit comprises: a first logic gate and a second logic gate, wherein an output of the first logic gate is coupled to a first input of the second logic gate, and an output of the second logic gate is coupled to a first input of the first logic gate; and wherein a second input of the first logic gate receives the buffered data clock signal and a second input of the second logic gate receives the burst end signal. The echo pulse generator comprises: a first inverting delayer circuit for receiving the buffered data clock signal, and producing an output signal by inverting and delaying the received signal; a first AND gate receiving the buffered data clock signal and the output signal of the first inverting delayer circuit, and producing an output signal; a first NOR gate receiving the buffered data clock signal and the output signal of the first inverting delayer circuit, and producing an output signal; a first OR gate receiving the output of the first AND gate and the output of the first NOR gate, and producing an output signal; and a second AND gate receiving the pulse enable signal and the output signal of the first OR gate, and generating the number of sequential echo clocks corresponding to the burst length count. The reset circuit comprises: a second inverting circuit receiving the pulse enable signal and producing an output signal; a second NOR gate receiving the output signal of the second inverting delayer circuit and the pulse enable signal, and producing an output signal; and a second OR gate receiving the output signal of the second NOR gate and a power-up signal, and producing the reset signal.
The semiconductor memory device input circuit may also comprise: data input buffer means receiving input data and outputting buffered input data; echo clock generator means receiving a burst length count and a data clock at a frequency, and sequentially generating a number, corresponding to the burst length count, of echo clocks at twice the frequency; and input data transmission means receiving the buffered input data and the echo clock and generating clocked input data synchronously with the echo clock. The echo clock generator means comprises: means for buffering the data clock and generating a buffered data clock signal; means for counting the number of sequential echo clocks; and means, coupled to the means for buffering and the means for counting, for generating the number of sequential echo clocks corresponding to the burst length count. The means for buffering the data clock comprises: means for detecting the voltage of the data clock based on a lower reference voltage, and producing a first output signal; means for detecting the voltage of the data clock based on an upper reference voltage which is higher than the lower reference voltage, and producing a second output signal; and means, coupled to the first and second output signals, for generating the buffered data clock signal, wherein the buffered data clock signal is transited when the voltage of the data clock decreases to below the lower reference voltage or increases to above the upper reference voltage. The means for counting comprises: counting signal generator means for counting the echo clock and generating a plurality of counting signals representative of the number of sequential echo clocks; and means responsive to the counting signals for generating a burst end signal when the number of sequential echo clocks corresponds to the burst length count, wherein the means for generating the number of sequential echo clocks is responsive to the burst end signal.
The invention also encompasses a computer system comprising: a processing unit that generates a data clock and input data to be written to a semiconductor memory device, and generates a burst length count, wherein the processing unit is coupled to the semiconductor memory device; the semiconductor memory device having an input circuit comprising: a data input buffer receiving input data and outputting buffered input data; an echo clock generator receiving a data clock at a frequency and sequentially generating an echo clock at twice the frequency; and an input data transmission circuit receiving the buffered input data and the echo clock and generating clocked input data synchronously with the echo clock.
The invention encompasses a computer system comprising: a processing unit that generates a data clock and input data to be written to a semiconductor memory device, and generates a burst length count, wherein the processing unit is coupled to the semiconductor memory device; the semiconductor memory device having an input circuit comprising: data input buffer means receiving input data and outputting buffered input data; echo clock generator means receiving a burst length count and a data clock at a frequency, and sequentially generating a number, corresponding to the burst length count, of echo clocks at twice the frequency; and input data transmission means receiving the buffered input data and the echo clock and generating clocked input data synchronously with the echo clock.
The invention also encompasses a computer system comprising: a processing unit that generates a data clock and input data to be written to a semiconductor memory device, and generates a burst length count, wherein the processing unit is coupled to the semiconductor memory device; the semiconductor memory device having an input circuit comprising: data input buffer means receiving input data and outputting buffered input data; echo clock generator means receiving a data clock at a frequency and sequentially generating an echo clock at twice the frequency; and input data transmission means receiving the buffered input data and the echo clock and generating clocked input data synchronously with the echo clock.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and advantages of the present invention will become more apparent by describing in detail a preferred embodiment thereof by reference to the attached drawings in which:
FIG. 1 is a block diagram of a conventional data input circuit;
FIG. 2 is a waveform diagram showing various times that affect the clock cycle time t CC in a conventional data input circuit;
FIG. 3 is a block diagram of an embodiment of a data input circuit including an echo clock generator according to the present invention;
FIG. 4 is a schematic showing an embodiment of the input data transmission unit 305 of FIG. 3;
FIG. 5 is a schematic showing an embodiment of the echo clock generator 303 of FIG. 3;
FIG. 5A is a waveform diagram of the operation of the echo clock generator 303 shown in FIG. 5.
FIG. 6 is a schematic showing an embodiment of the echo clock buffer 501 of FIG. 5;
FIG. 7 is a schematic showing an embodiment of the echo pulse generator 503 of FIG. 5;
FIG. 8 is a timing diagram of the operation of the echo pulse generator in FIG. 7;
FIG. 9 is a schematic showing an example of the reset pulse generator 509 of FIG. 5;
FIG. 10 is a block diagram showing an embodiment of the burst length counter 505 of FIG. 5;
FIG. 11 is a schematic showing an embodiment of the counting signal generator 1001 of FIG. 10;
FIG. 12 is a schematic showing an embodiment of the A-type counter 1101 of FIG. 11;
FIG. 13 is a schematic showing an embodiment of the B-type counters 1102 to 1109 of FIG. 11; and
FIG. 14 is a schematic showing an embodiment of the burst signal generator 1003 of the burst length counter 505 of FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the present invention will be described by reference to the appended drawings in which the same reference numerals in the drawings represent the same element throughout the drawings.
In FIG. 3 shows a data input circuit having an echo clock generator according to the present invention. The data input circuit includes a data input buffer 301, an echo clock generator 303, and an input data transmission unit 305. The data input buffer 301 buffers external input data DIN and provides buffered input data DI. The echo clock generator 303 generates a pulse XCON in response to the transition of an external data clock DCLK until the number of the external data clock signals reach a predetermined number. The input data transmission unit 305 transmits an output signal DIX in response to the output signal XCON of the echo clock generator 303. Typically, the input signals DIN and DCLK are synchronized to each other. The data input buffer 301 and echo clock generator 303 may be located in the memory controller or in the memory chip. The signal XCON is output at twice the frequency of the external data clock DCLK. The data DIN and the external data clock DCLK are sent or controlled by the central processing unit, which also controls the amount of data written to memory in a single block.
FIG. 4 shows an example of the input data transmission unit 305 of FIG. 3. Referring to FIG. 4, the input data transmission unit 305 includes a first inverting buffer 401, a transmission gate 403, and a second inverting buffer 405. The signal XCON from the echo clock generator 303 is input to one control input of the transmission gate 403, and a signal XCON which is inverted via a third inverting buffer 407 is input to the other control input thereof, so that an output signal N402 of the first inverting buffer 401 is transmitted by the transmission gate 403 in response to the signal XCON. The output of the transmission gate 403 is buffered by the second inverting buffer 405 to generate the output signal DIX.
Thus, when the transition of the external data clock DLCK occurs, the echo clock generator 302 generates a pulse XCON. Accordingly, the transmission gate 403 of the input data transmission unit 305 is turned on, so that an output signal DI of the data input buffer 301 is transmitted to the memory chip as clocked input data DIX. The echo clock generator 303 continues to generate XCON pulses until the number of external data clock signals DCLK reaches a predetermined number corresponding to the preset burst length of the data.
FIG. 5 shows an embodiment of the echo clock generator of the data input circuit according to the present invention, and FIG. 5A is a waveform diagram showing the operation of the circuit. Referring to FIG. 5, the echo clock generator includes an echo clock buffer 501, an echo pulse generator 503, a burst length counter 505, a latch 507, and a reset pulse generator 509. The echo clock buffer 501 is further described in FIG. 6, the echo pulse generator 503 is further described in FIG. 7, the burst length counter 505 is further described in FIGS. 10-14, and the reset pulse generator 509 is further described in FIG. 9.
The echo clock buffer 501 outputs a buffered data clock signal XPUL by buffering an external data clock signal DCLK. The echo pulse generator 503 is enabled by a pulse enable signal PULEN, and it generates an output signal XCON as a pulse in response to the transition of the output signal XPUL of the echo clock buffer 501. The burst length counter 505 is preset by a reset pulse RESET, and a burst end signal BLCNT is generated when the number of pulses of the output signal XCON of the echo pulse generator 503 reaches a predetermined number. The predetermined number in the burst length counter 505 is set in accordance with states of inputs SZ2B, SZ4B, SZ8B, and SZFFULL. The SZ inputs are may be controlled by the memory control circuitry associated with the central processing unit.
The latch 507 generates the pulse enable signal PULEN which is preset by the reset pulse RESET, latched by the first transition of the output signal XPUL, and released from the latch by the transition of the output signal BLCNT. The structure of the latch 507 will now be described in detail. The latch 507 includes a first NOR gate 511 and a second NOR gate 513. The first NOR gate 511 receives an output signal VRPRE of the second NOR gate 315 and a signal XPUL produced in response to the signal DCLK. The second NOR gate 513 receives the output signal BLCNT from the burst length counter 505 and an output signal N512 from the first NOR gate 513.
The operation of the echo clock generator 303 is best described by reference to the schematic diagram in FIG. 5 and timing diagram in FIG. 5A. In the initial operation of the latch 507, the output signal BLCNT is in a "low" state. When the output signal XPUL transitions to a "high" state, the output signal N512 of the first NOR gate 511 goes "low," and PULEN is latched "high." This causes the output signal VPRE of the second NOR gate 513 to be latched to a "high" state. Then, even though the output signal XPUL of the echo clock buffer 501 may transition continuously, the output signal PULEN remains latched high. The echo pulse generator 503 generates XCON pulses in response to transitions of signal XPUL. After the echo pulse generator 503 generates a predetermined number of pulses XCON corresponding to the length of the data burst preset in the burst length counter 505, the output signal BLCNT from the burst length counter 505 transition to a "high" state. When BLCNT transitions high, then the output signal PULEN of the latch 507 goes "low," there by disabling the echo pulse generator 503 and preventing it from generating more XCON pulses.
The reset pulse generator 509 generates the reset pulse RESET in response to the transition of the pulse enable signal PULEN. The latch 507 includes a latch release portion 515. The latch release portion 515 resets the latch 507 at "power-up" (via VCCHB) or when the reset pulse RESET is generated.
FIG. 6 shows an embodiment of the echo clock buffer 501 of FIG. 5. Referring to FIG. 6, the echo clock buffer 501 includes a lower current mirror 601, an upper current mirror 603, and latch 605. The lower current mirror 601 buffers the voltage of the data clock DCLK based on a predetermined lower reference voltage VRL. The upper current mirror 603 buffers the voltage of the data clock DCLK based on a predetermined upper reference voltage VRH which is higher than the lower reference voltage VRL. The latch 605 receives an output signal N602 from the lower current mirror 601 as a first input signal and an output signal N604 from the upper current mirror 603 as a second input signal to generate the output signal XPUL, which transitions when the level of the data clock signal DCLK decreases below a lower reference voltage VRL or increases above an upper reference voltage VRH. For a terminated interface that relies on a Vref reference voltage, VRL is typically Vref-0.1 V, and VRH is typically Vref+0.1 V, although other voltages may be used.
The lower current mirror 601 includes a pull-up transistor 607, a first PMOS transistor 609, a second PMOS transistor 611, a first NMOS transistor 613, a second NMOS transistor 615 and a third NMOS transistor 617. The pull-up transistor 607 has a source connected to a power voltage VCC and is turned on when an echo clock enable signal XEN is activated, that is, when the gate signal of the pull-up transistor 607 is input as a "low" signal. The first PMOS transistor 609 has a source connected to a drain of the pull-up transistor 607 and a gate to which the lower reference voltage VRL is applied. Also, the second PMOS transistor 611 has a source connected to the drain of the pull-up transistor 607 and a gate to which the data clock signal DCLK is applied. The first NMOS transistor 613 has a source connected to a ground voltage VSS, and a common connect point N610 to which a gate and a drain of the first NMOS transistor 613 are commonly connected to the drain of the first PMOS transistor 609. Also, the second NMOS transistor 615 has a source connected to the ground voltage VSS, a gate connected to the common connect point N610, and a drain connected to a drain of the second PMOS transistor 611, to generate the output signal N602 of the lower current mirror 601. The third NMOS transistor 617 has a source connected to the ground voltage VSS and a drain connected to the output port N602 of the lower current mirror 601, and it is turned on when the echo clock enable signal XEN is disabled, thereby pulling N602 to ground.
Thus, when the signal XEN is enabled to "high," the lower current mirror 601 responds to the data clock signal DCLK. When the level of the data clock signal DCLK is higher than that of the lower reference voltage VRL, a voltage Vgs between the gate and the source of the first PMOS transistor 609 is higher than that of the second PMOS transistor 611. Thus, the voltage of the common connect point N610 increases, so that the effect of the second NMOS transistor 615 becomes stronger than that of the second PMOS transistor 611. Thus, the voltage of the output port N602 of the lower current mirror 601 decreases toward the voltage VSS.
In contrast, when the level of the data clock signal DCLK is lower than that of the lower reference voltage VRL, the voltage Vgs of the first PMOS transistor 609 is lower than that of the second PMOS transistor 611. Thus, the voltage of the common connect point N610 decreases, so that the effect of the second NMOS transistor 615 becomes weaker than that of the second PMOS transistor 611. Thus, the voltage of the output port N602 of the lower current mirror 601 increases toward the voltage VCC.
The upper current mirror 603 includes a pull-down transistor 619, a third PMOS transistor 625, a fourth PMOS transistor 627, a fifth PMOS transistor 629, a fourth NMOS transistor 621, and a fifth NMOS transistor 623. The pull-down transistor 619 has a source connected to the ground voltage VSS and is turned on when the echo clock enable signal XEN is activated. The fourth NMOS transistor 621 has a source connected to a drain of the pull-down transistor 619 and a gate to which the upper reference voltage VRH is applied. The fifth NMOS transistor 623 has a source connected to the drain of the pull-down transistor 619 and a gate to which the data clock signal DCLK is applied. The third PMOS transistor 625 has a source connected to the power voltage VCC, a gate and a drain connected to a common connect point N622 and to a drain of the fourth NMOS transistor 621. The fourth PMOS transistor 627 has a source connected to the power voltage VCC, a gate connected to the common connect point N622, and a drain connected to a drain of the fifth NMOS transistor 623, to generate an output signal N604 of the upper current mirror 603. A fifth PMOS transistor 629 has a source connected to the power voltage VCC and a drain connected to the output port N604 of the upper current mirror 603, and it is turned on when the echo clock enable signal XEN is disabled, thereby pulling port N604 high.
Thus, when the signal XEN is enabled to "high," the upper current mirror 603 responds to the data clock signal DCLK. When the level of the data clock signal DCLK is lower than that of the upper reference voltage VRH, a voltage Vgs of the fourth NMOS transistor 621 is higher than that of the fifth NMOS transistor 623. Thus, the voltage of the common connect point N622 decreases, so that the effect of the fourth PMOS transistor 627 becomes stronger than that of the fifth NMOS transistor 623. Thus, the voltage at the output port N604 of the upper current mirror 603 increases toward the voltage VCC.
In contrast, when the level of the data clock signal DCLK is higher than that of the upper reference voltage VRH, voltage Vgs of the fourth NMOS transistor 621 is lower than that of the fifth NMOS transistor 623. Thus, the voltage of the common connect point N622 increases, so that the effect of the fourth PMOS transistor 627 becomes weaker than that of the fifth NMOS transistor 623. Thus, the voltage at the output portion N604 of the upper current mirror 603 decreases toward the voltage VSS.
The latch 605 includes an inverter 631, a first NAND gate 633, a second NAND gate 635 and an inverting buffer 637. The first NAND gate 633 receives an output signal N632 from the inverter 631 as a first input signal. The second NAND gate 635 performs a NAND operation on the output signal N604 of the upper current mirror 603 and an output signal N634 of the first NAND gate 633, and it generates an output signal N636 that is input to the first NAND gate 633 as a second input signal. The inverting buffer 637 inverts the output signal of the first NAND gate 633 and generates the output signal XPUL.
The echo clock buffer 501 in FIG. 6 operates as follows, when the signal XEN is enabled to a high level. When the level of the data clock signal DCLK is lower than that of the lower reference voltage VRL, the level of the output signal N602 of the lower current mirror 601 increases. This causes the level of the output N632 of the inverter 631 to go "low," so that the output signal XPUL of the echo clock buffer 501 decreases to a "low" level. At the same time, the level of the output signal N604 of the upper current mirror 603 goes "high," so that the level of the output N636 of the second NAND gate 635 goes "low." When the level of the data clock signal DCLK increases from a level that is lower than the lower reference voltage VRL to a level between the lower reference voltage VRL and the upper reference voltage VRH, the level of the output N602 of the lower current mirror 601 decreases. This causes the level of the output N632 of the inverter 631 to go "high." However, since the logic state of the output signal N636 of the second NAND gate 635 is maintained at a "low" level, the level of the output signal XPUL of the echo clock buffer 501 does not change.
When the level of the data clock signal DCLK is higher than the upper reference voltage VRH, the level of the output N602 of the lower current mirror 601 decreases. This causes the level of the output N632 of the inverter 631 to go "high." At the same time, the level of the output N604 of the upper current mirror 603 to go "low," so that the logic state of the output signal N636 of the second NAND gate 635 goes "high." This causes the level of the output signal XPUL to increase to a "high" level. When the level of the data clock signal DCLK decreases from a level that is higher than the upper reference voltage VRH to a level between the lower reference voltage VRL and the upper reference voltage VRH, the level of the output N604 of the upper current mirror 603 increases. However, since the logic state of the output signal N634 of the first NAND gate 633 is maintained at "low," the logic state of the output signal N636 of the second NAND gate 635 is maintained at "high." Thus, the level of the output signal XPUL of the echo clock buffer 501 does not change.
FIG. 7 is a diagram showing the echo pulse generator 503 of FIG. 5. Referring to FIG. 7, the echo pulse generator 503 includes an inverting delayer 701, a first AND gate 703, a NOR gate 705, an OR gate 707, and a second AND gate 709. The inverting delayer 701 inverts the output signal XPUL received from the echo clock buffer 501 and then delays the inverted result. The inverting delayer 701 maybe comprised of an odd number of inverters arranged in series. The first AND gate 703 performs an AND operation on the signal XPUL and an output signal N702 of the inverting delayer 701. The NOR gate 705 performs a NOR operation on the signal XPUL and the output signal N702 of the inverting delayer 701. The OR gate receives signal N704 and signal N706, and it generates output signal N708. The second AND gate 709 is enabled by the pulse enable signal PULEN and it generates the signal XCON in response to signal N708 from the OR gate 707.
FIG. 8 is a timing diagram of the signals in the echo pulse generator 503 in FIG. 7 according to the transition of the signal XPUL. According to the operation of the echo pulse generator described in FIG. 7 and FIG. 8, whenever the logic state of the signal XPUL transitions from "high" to "low" or from "low" to "high," the signal N708 is generated as a pulse. Also, when the logic state of the pulse enable signal PULEN is high, the output signal XCON of the echo pulse generator is also generated as a pulse in response to the transition of the output signal N708 of the OR gate 707. However, when the logic state of the pulse enable signal PULEN is "low," the echo pulse generator does not generate a pulse XCON.
FIG. 9 is a diagram showing an example of the reset pulse generator 509 of FIG. 5. The reset pulse generator 509 generates a reset pulse RESET when the signal PULEN changes from "high" to "low." Referring to FIG. 9, the reset pulse generator 509 includes an inverting delayer 901, a NOR gate 903 and an OR gate 905. The inverting delayer 901 inverts and delays the pulse enable signal PULEN. The NOR gate 903 receives the pulse enable signal PULEN and the output signal N902 of the inverting delayer 901. Thus, whenever the logic state of the pulse enable signal PULEN transitions from "high" to "low," the output signal N904 of the first NOR gate 903 transitions from "low" to "high." The OR gate 905 receives the signal N904 and a power-up signal VCCHB as a high pulse during power-up. Thus, during power-up or when the logic state of the pulse enable signal PULEN transitions from "high" to "low," the OR gate 905 generates the reset signal RESET as a high-going pulse.
FIG. 10 is a diagram showing an example of the burst length counter 505 of FIG. 5. Referring to FIG. 10, the burst length counter 505 includes a counting signal generator 1001 and a burst signal generator 1003. The counting signal generator 1001 counts the number of pulses of the output signal XCON of the echo pulse generator 503 to generate counting signal groups CNT0 through CNT8. The burst signal generator 1003 receives the counting signal groups to generate a signal BLCNT corresponding to the burst length. The burst signal generator 1003 also receives signals representing the predetermined burst length: SZ2B, SZ4B, SZ8B, and SZFULL. The burst length counter 505 counts XCON pulses until they reach the predetermined number set by SZ2B to SZFULL, at which time the burst length counter 505 generates the signal BLCNT.
FIG. 11 is a diagram showing an embodiment of the counting signal generator 1001 of FIG. 10. Referring to FIG. 11, the counting signal generator 1001 includes an A-type counter 1101 and a plurality of B-type counters 1102 through 1109. The A-type counter 1101 is shown in FIG. 12, and the B-type counter is shown in FIG. 13. The operation of the A-type and B-type counters in FIGS. 12-13 will be discussed first, prior to describing the operation of the counting signal generator 1001 in FIG. 11.
FIG. 12 is a diagram showing an example of the A-type counter 1101 of FIG. 11. Referring to FIG. 12, the A-type counter 1101 includes a NOR gate 1201, first and second inverters 1203 and 1215, a first transmission gate 1205, a first latch 1207, a second transmission gate 1209, a second latch 1211, and an NMOS transistor 1213.
The NOR gate 1201 performs an OR operation on the reset pulse RESET and the signal XCON, and inverts the OR-operated result to produce signal N1210. The first inverter 1203 inverts the logic state of the output signal CNTO of the A-type counter 1101. The first transmission gate 1205 transmits signal N1 204 to its output when signal N1210 is in a "high" state. The first latch 1207 latches the signal transmitted by the first transmission gate 1205, and the second transmission gate 1209 transmits signal N1208 from the first latch 1207 when signal N1210 is in a "high" state. The second latch 1211 latches the signal transmitted by the second transmission gate 1207. Latch 1207 is initialized when NMOS transistor 1213 having a source connected to the ground voltage VSS is gated by the reset pulse RESET, thereby presetting the input of the first latch 1207 to ground.
The A-type counter 1101 operated as follows. First, when the reset pulse RESET is activated to "high," the NMOS transistor 1213 is turned on so that the input N1206 of the first latch 1207 is precharged to the voltage VSS, thereby setting the signal N1208 "high" at the output of the first latch 1207. At that time, the second transmission gate 1209 is turned on to set the input of second latch 1211 "high," and the logic state of the output signal CNT0 of the A-type counter 1101 goes "low." This causes the signal N1204 from the first inverter 1203 to become high. When the reset pulse RESET is disabled to "low," the NMOS transistor 1213 is turned off and the first transmission gate 1205 is turned on, causing the output signal N1208 of the first latch 1207 to go "low." At this time, the second transmission gate 1209 is turned off.
When the signal XCON from the echo pulse generator 503 is activated to "high," the second transmission gate 1209 is turned on, and the logic state of the output signal CNT0 of the A-type counter 1101 transitions to "high." Also, when the signal XCON is disabled to "low," the first transmission gate 1209 is turned on, so that the signal N1208 transitions to "high." As above, whenever the output signal XCON of the echo pulse generator 503 generates a pulse, the A-type counter 1101 produces a change in the logic state of the output signal CNT0.
FIG. 13 is a diagram showing an embodiment of the B-type counters 1102 through 1109 of FIG. 11. Referring to FIG. 13, the B-type counters are very similar to the A-type counter, except that the B-type counters accept a "carry" input to the NOR gate 1301. Each NOR gate 1301 of the B-type counters 1102 through 1109 receives the reset pulse RESET, the output signal XCON from the echo pulse generator 503, and a carry signal CARRYB i-1 representing the logic state of the output signal of the previous counters. As shown in FIG. 11, when the logic state of all output signals of the previous counters is "high," the logic state of the signal CARRYB i-1 goes "low." Comparing FIGS. 12 and 13, it can be seen that when the logic state of the signal CARRYB i-1 goes "low," the B-type counters operate like the A-type counter.
Referring to the A-type counter in FIG. 12 and the B-type counters in FIG. 13, the operation of the counting signal generator in FIG. 11 will now be described as follows. First, when a reset operation occurs by the reset pulse RESET, the output signals CNT0 through CNT8 of the A-type and B-type counters 1101 through 1109 are preset to 0. When the signal XCON generates a first pulse, the logic state of the output signal CNTO goes to "1." When the signal XCON generates a second pulse, the logic state of the output signal CNT0 goes to "0," and that of the output signal CNT1 goes to "1." When the signal XCON generates a third pulse, the logic state of the output signal CNT0 goes to "1." When the signal XCON generates a fourth pulse, the logic state of the output signals CNT0 and CNT1 goes to "0," and the logic state of the output signal CNT2 goes to "1." As above, whenever the signal XCON generates a pulse, the output signals CNT0 through CNT8 of the counting signal generator 1001 sequentially change in a binary manner to count the number of pulses of the signal XCON. Finally, when the signal XCON generates pulses corresponding to a predetermined number, the reset signal RESET is activated, so that all output signals CNT0 through CNT8 are preset to "0."
FIG. 14 is a diagram showing the burst signal generator 1003 of the burst length counter of FIG. 10. The burst signal generator 1003 generates the output signal BLCNT when the number of pulses of the output signal XCON generated from the echo pulse generator 503 reaches a predetermined number of input pulses, in response to the counting signal groups CNT0 through CNT8. The signals SZ2B, SZ4B, SZ8B, and SZFULL represent the burst length of data to be transmitted to the memory device. The signals may be preset by fuse circuits or may be controlled through a latch or mode set register. In FIG. 14, SZ2B represents a signal that is "high" when the burst length of the input data is 2 or greater, SZ4B represents a signal that is "high" when the burst length of the input data is 4 or greater, SZ8B represents a signal that is "high" when the burst length of the input data is 8 or greater, and SZFULL represents a signal that is "high" when the burst length of the input data corresponds to the maximum burst length.
For example, we will assume that the burst length of the input data is 4. Here, the signals SZ2B and SZ4B are "high," and the signals SZ8B and SZFULL are "low." During data transmission to the memory device, when the echo pulse generator 503 generates the fourth pulse of the signal XCON, the signal CNT2 goes "high" while the remaining counting signal groups CNT0, CNT1 and CNT3 through CNT8 become "low." At this time, the logic state of the output signal BLCNT transitions from "low" to "high," thereby signaling that the desired length of burst data has been transmitted to the memory device.
As described, in the data input circuit above, the echo clock generator 303 generates pulses in response to a predetermined length of a data burst. The pulses correspond to an echo clock that is transmitted in the memory devices simultaneously with the data. The data is stored in the internal memory cells of the memory device.
The present invention is not limited to the particular form illustrated, and further modifications and alterations will occur to those skilled in the art within the spirit and scope of the present invention. For example, many types of counters are well-known in the art, and they may be substituted for the type-A and type-B counters shown in the preferred embodiment. Also, the counters may operate by counting the data clock rather than the echo clock. In addition, different combinational logic or comparator circuitry may be substituted for the logic circuitry shown in FIG. 14. The counting circuitry may be altered to use a presettable counter that counts to zero rather than a counter that counts up to the burst length. Many similar alterations known to one of ordinary skill in the art may be performed within the scope of this invention.
Therefore, the data access time in a synchronous semiconductor memory device is improved by eliminating the effects of the time t AC required from the clock synchronization to the data output and the time t FL required for transmitting the data from the controller to the memory.
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A data input circuit for a semiconductor memory device uses an echo clock generator to reduce the clock cycle time. The echo clock is transmitted in the memory device with the data, thereby reducing the effects of clock skew and increasing the overall device operation speed. The circuit is particularly applicable to double data rate synchronous DRAM (DDR-SDRAM) circuitry.
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FIELD OF THE INVENTION
This invention relates generally to automatic package or article wrapping methods and devices. More particularly, it relates to a method and apparatus for heat sealing articles within a thermoplastic film as the articles move at a high rate of speed through an article wrapping machine.
BACKGROUND OF THE INVENTION
Machines for wrapping articles and packages with a heat sealable thermoplastic film are known art. Indeed, such machines have been utilized commercially for several decades. In a typical configuration, the package wrapping machine advances a steady stream of articles along a conveyer belt and towards a plastic envelope. This plastic envelope is formed by providing a roll of center-folded thermoplastic film which is situated to one side or the other of the conveyer. A continuous sheet of center-folded plastic film is pulled from the roll and is presented along a line which is typically perpendicular to the conveyer and perpendicular to the path of the articles which are moving along that conveyer. Means for separating the adjacent layers of film in the center-folded configuration is provided by use of a film inverter. The film inverter separates and opens the film envelope and reverse folds, or inverts, the film envelope such that the advancing articles are effectively captured by the film envelope and interposed between the adjacent film layers. As the enveloped articles continue their advance, leaving the film inverting area of the machine, one continuous side or edge of the film envelope remains open. A side sealing mechanism is provided for effectively welding or sealing the continuous side or edge of the adjacent and open film layers. Once side sealed, this mechanism provides a generally tube-like thermoplastic envelope for the articles. As the articles and the continuous side sealed plastic film envelope which covers them continue to advance along the machine, an end sealer effectively welds or seals a leading edge of the envelope and then reciprocates to the rear of the article, or simply allows the article to advance, to then weld or seal the trailing edge of the envelope. In this fashion, the leading edge of the next-in-line article is also sealed and the process is repeated.
In the experience of these inventors, one problem which is inherent to the side-sealing action of presently used packaging machines is that incomplete seams or welds often result in the side sealer portion of the machine. This is particularly true if the film tensions are not adequately maintained within the side-sealing portion of the machine as the film is advanced. That is, thermoplastic film which is not properly or adequately grasped within, or advanced by, the side sealer mechanism can result in adjacent film layers which are misaligned or simply not maintained in close enough proximity to one another to form a proper weld or seal as the layers are drawn into the vicinity of a hot wire or weld element. Similarly, adjacent film layers which are not maintained in proper alignment may result in welds which not only appear crumpled or wrinkled, but which are effectively incomplete. If adjacent film layers cannot be brought close enough together during the side-sealing process, it may be necessary to make other adjustments such as increasing the temperature of the weld element, or increasing the time that any given portion of the continuous film layers must remain in welding vicinity to the weld element. This latter adjustment essentially amounts to a slowing down of the packaging process and a net reduction in production.
Another problem which arises is the need to replace the “consumables” of the packaging machine. In the experience of these inventors, the consumables take two forms—the drive belts of the side sealer mechanism which are functionally intended to grasp and advance the thermoplastic film—and the weld element itself. In the case of any particular packaging project, drive belt breakage and weld element burn-out are recognized, though unwelcomed, inconveniences. Once broken, drive belt replacement is absolutely necessary for the continued successful operation of the machine. And, suffice it to say that no welds will be made without a properly functioning weld element. The replacement of such consumables, however, is often easier said than done. The reality being that production must come to a halt and, in the case of a broken belt, the belt drive and tail pulleys must be untensioned by use of the proper tools to allow a new belt to be stretched over them and properly seated back into place. In the case of the malfunctioning or shorted out weld element, it too must be replaced by untensioning the weld element fastening means to either end of the weld element by use of the proper tools and by resetting the newly placed weld element to the proper depth and taper so as to allow optimum performance of the weld element. All of this often requires the use of several tools, is time consuming and is surely not something that the production manager looks forward to.
Further in the experience of these inventors, the weld or heat element of the present generation of side sealer mechanisms which are incorporated into packaging machines may also have a tendency to degrade a weld which is, at least initially, completely and acceptably formed. That is, the weld which is formed within the side sealer may leave the welding area in perfect or near perfect condition. If the weld is overexposed to the heat of the hot wire or weld element, by spending too much time near or traveling too close to the wire or element after the weld is formed, the weld quality will be compromised. In extreme cases, the weld may actually be reopened. This too is an unacceptable result in the overall quality of production.
Another problem associated with present packaging machines is that the end sealing mechanisms incorporated in such machines create end seals which may also display weld inconsistencies. One explanation for this, in the view of these inventors, is that the article which is enveloped within the so-called plastic film “tube” typically has some height or thickness to it. While some articles are very thin, others are more bulky. For articles with any substantial girth, sealing of the film should optimally occur at or very near to the horizontal midline of the article. In this fashion, an equal amount of film is pulled down around the article from the top film layer as is pulled up around the article from the bottom film layer. This is not, however, how most articles are typically end sealed using machines that are available today. To the contrary, the surface upon which the article rests typically provides the horizontal reference point at which the article is sealed instead.
SUMMARY OF THE INVENTION
The present invention overcomes these problems and disadvantages. It provides a new and useful method and apparatus for securely grasping and advancing the adjacent layers of thermoplastic film through the side sealing mechanism of a packaging machine. It also provides a new and useful method and apparatus for maintaining integrity of the heat-induced weld which is created at the side sealing mechanism and at the end sealing mechanism of the packaging machine. It also provides a new and useful method and apparatus which accomplishes all of this while making the side sealing mechanism an apparatus in which the consumables utilized within the mechanism can be maintained or replaced by the user without the need for tools or special adjustments.
The present invention accomplishes this by providing a plurality of film grasping belts which travel about two sets of cooperating pulleys, each pulley set including a drive pulley, a tail pulley and a number of idler pulleys disposed between the drive pulley and the tail pulley. Each pulley—drive, tail and idler—has two circumferential belt grooves defined within it, each belt groove being functionally adapted to allow the travel of a belt along it as the pulley is rotated about a central axis. A first line of travel about the pulleys is defined within the cooperating pulleys along a path which is substantially parallel with the line of travel of an article which is being advanced by the wrapping machine. The second pulley line of travel is defined within the cooperating pulleys along a path which diverges away at a slight angle relative to that path of travel. The grooves or pathways of the cooperating drive and tail pulleys of each set are cooperatively tapered or beveled so as to allow this divergence and to prevent the belt from “walking” out of the grooves. The belts which are used in the method and apparatus of the present invention are V-ribbed belts, the “V-ribbed” portion of the belts being disposed outwardly of the pulleys and the flat belt portion being immediately adjacent the pulleys. Each pair of cooperating pulleys is offset by an amount which is equal to one-half of the pitch of one rib and groove of each V-ribbed belt such that the belts engage each other in tooth-meshing fashion. This meshing action is functionally adapted to firmly grasp a pair of thermoplastic film layers therebetween and to prevent slippage therefrom. It should also be noted that the contour of the belt may be varied without deviating from the scope of this invention.
The tail pulley of each pulley assembly is, in the preferred embodiment, mounted in an offset cam fashion and is spring loaded to apply tension to the belts. A rotational handle is also provided. This feature allows torsional pressure to be applied to the tail pulley by the user for quick and tool-less removal of a damaged or broken belt.
Disposed between the divergent belt paths is a hot wire assembly which is functionally adapted to weld the thermoplastic layers together as the plastic film passes near the hot wire. This hot wire assembly is constructed such that the hot wire itself drops down along a line which is at a slight angle relative to the horizontal. It is also constructed such that the hot wire itself is divergent away from the path of travel of the article being sealed. This feature prevents over-exposure of the weld to the hot wire thereby maintaining weld integrity. The hot wire assembly, in the preferred embodiment, utilizes a first wire mounting block which is stationary and a second wire mounting block which is rotatable. A rotational handle is provided. This feature allows torsional pressure to be applied to the rotatable mounting block by the user for quick and tool-less removal of a damaged or burned out hot wire. The mounting blocks of the hot wire assembly are also provided with means for allowing insertion of the hot wire end connectors at a predetermined depth which preserves the preset angle relative to the horizontal and which does away with any need to measure or manually adjust wire depth or angle.
Following the side sealing apparatus of the present invention is an end sealing apparatus which includes an elevation screw for adjusting the end seal location at a point which lies at the middle of the vertical height of the article to be wrapped. The elevation screw has a elevation screw nut which is attached to it, which is in turn attached to a rocker assembly for moving a horizontally disposed and vertically moving top seal bar downwardly and a cooperating bottom seal bar, likewise horizontally disposed and vertically movable, upwardly such that the top and bottom seal bars meet at the vertical center of the article.
In summary, the advantages of the invention are that it provides a method and apparatus for securely grasping and advancing the adjacent layers of thermoplastic film through the side sealing mechanism of a packaging machine; that it maintains integrity of the heat-induced weld which is created at the side sealing mechanism and at the end sealing mechanism; and which makes the side sealing mechanism an apparatus in which the consumables utilized by it can be quickly and easily maintained without the need for tools or readjustment.
The foregoing and other advantages of the method and apparatus of the present invention will be apparent from the description which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a packaging machine having a side sealing apparatus and an end sealing apparatus, both of which are constructed in accordance with the present invention.
FIG. 2 is an enlarged front and right side perspective view of the side sealing apparatus of the present invention.
FIG. 2A is a greatly enlarged right side elevational view of the cooperating belts shown in the side sealing apparatus shown in FIG. 2 .
FIG. 2B is another greatly enlarged right side elevational view showing a weld created along adjacent layers of thermoplastic material as they pass through the side sealing apparatus shown in FIG. 2 .
FIG. 3 is a rear and left side exploded perspective view of one subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 4 is a rear and left side exploded perspective view of another subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 5 is a further enlarged front right side exploded perspective view of another subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 6 is a partial and cross-sectioned right side elevational view of the side sealing apparatus shown in FIG. 2 .
FIG. 7 is an exploded front and right side perspective view of a tail pulley subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 8 is an enlarged cross-sectioned view of the tail pulley subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 9 is an enlarged cross-sectioned right side elevational view of a drive pulley subassembly of the apparatus shown in FIG. 2 .
FIG. 10 is an enlarged exploded front and right side perspective view of an idler pulley subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 11 is a further enlarged cross-sectioned right side elevational view of the idler pulley subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 12 is a top plan view of one set of idler pulleys shown in FIG. 2 .
FIG. 13 is an enlarged and exploded front and right side perspective view of a hot wire subassembly of the side sealing apparatus shown in FIG. 2 .
FIG. 14 is a further enlarged cross-sectioned right side elevational view of the stationary attachment portion of the hot wire subassembly shown in FIG. 13 .
FIG. 15 is a further enlarged cross-sectioned right side elevational view of the pivoting attachment portion of the hot wire subassembly shown in FIG. 13 .
FIG. 16 is a partial cross-sectioned and front elevational view of the hot wire subassembly shown in FIGS. 2 and 13.
FIG. 17 is a further enlarged and partial cross-sectioned top plan view of the hot wire and pulley subassemblies of the side sealing apparatus shown in FIG. 2 .
FIG. 18 is a left side elevational view of the end sealing apparatus of the present invention.
FIG. 19 is a partially cross-sectioned rear elevational view of the end sealing apparatus taken along line 19 — 19 of FIG. 18 .
DETAILED DESCRIPTION
Referring now to the drawings in detail, FIG. 1 illustrates a preferred embodiment of an apparatus utilizing the method of the present invention. The packaging machine, generally identified 10 , includes a main table portion 11 , a package conveyer belt 12 , a plastic film inverter 13 , and a discharge belt 15 . The packaging machine 10 also includes a side seal assembly, generally identified 20 , and an end seal assembly, generally identified 30 . An intermediate belt 14 is situated immediately adjacent the side seal assembly 20 .
As an article 8 to be wrapped approaches the film inverter 13 , the article 8 enters an envelope which is created by a center folded sheet of thermoplastic film 1 . The supply of film 1 is continuous and is fed from a roll (not shown) located to one side of the machine 10 . As the article 8 passes through the inverter 13 , there is a first layer 2 of thermoplastic film 1 which is disposed over the article 8 , and a second layer 3 disposed beneath the article 8 such that the article 8 will continue to be carried along the table 11 atop the second film layer 3 and into the vicinity of the side sealer assembly 20 . As the article 8 continues on its way, a continuous and open side 6 of the film envelope formed by the adjacent edges 4 , 5 of the film 1 remains. The side sealer assembly 20 captures this open side or edge 6 and effectively welds or seals it thereby creating a generally tube-like plastic film envelope which effectively encircles the article 8 . See FIG. 2 .
The side sealer assembly 20 is mounted to one side of the packaging machine 10 by means of a side seal bottom base plate 22 and a side seal top plate 21 . See FIG. 3 . The side seal base plate 22 and the side seal top plate 21 are separated by a pair of tubular column spacers 23 which are placed in tension by means of a rod 24 which is disposed to the inside of each spacer 23 by virtue of nuts 25 which are threaded onto the ends of the rods 24 . Also disposed between the side seal base plate 22 and the side seal top plate 21 is a first linear bearing shaft 26 and a second linear bearing shaft 27 . The first and second bearing shafts 26 , 27 , respectively, are each attached to the side seal top and base plates 21 , 22 , respectively, by means of a number of fasteners 28 . The first linear bearing shaft 26 is functionally adapted to slidably receive a top seal frame bearing 98 and a bottom seal bearing 99 . See FIG. 4 . Similarly, the second linear bearing shaft 27 is functionally adapted to slidably receive a second top seal frame bearing 96 and second bottom seal bearing 97 . The first and second top seal frame bearings 98 , 96 , respectively, are attachable to a seal frame upper back plate 90 . Similarly, the first and second bottom seal frame bearings 99 , 97 , respectively, are attached to a seal frame lower back plate 91 . A seal frame upper face plate 92 is provided as is a seal frame lower face plate 93 . The upper seal frame face and back plates 92 , 90 , respectively, are attached to each other by means of a plurality of bolts 89 and with a seal frame head spacer and seal frame tail spacer 94 , 95 , respectively, interposed between them. Similarly, the lower seal frame face and back plates, 93 , 91 , respectively, are attached to each other with the head and tail spacers 94 , 95 situated between them as well. It should be noted here that the bottom seal frame bearings 97 , 99 are, in the preferred embodiment, machined to be 0.046 in. thinner than their top seal frame counterparts 96 , 98 . The purpose for this is to mount the top face plate 92 in a plane which is 0.046 in. forward of a plane which defines the bottom face plate 93 . This detail will be discussed further later in this detailed description. It is also to be noted that the back plates and face plates, 90 , 91 , 92 , 93 , respectively, of the side sealer assembly 20 are shown attached to the packaging machine 10 in a given location. This location is determined by a number of factors, including which side of the machine 10 that the open side 6 of the film 1 is presented on and what direction the article 8 is to travel in. It is to be understood that, in the preferred embodiment, both top plates 90 , 92 and both bottom plates 91 , 93 could be interchanged so as to allow the article direction to change, and the side at which the film envelope edge 6 presents itself, as such is desired or required. In other words, the back and face plates, 90 , 91 , 92 , 93 , respectively, are functionally adapted to be assembled in another way and still come within the scope of the method and apparatus of the present invention. This is an advantage to the manufacturer, to production people and to end users alike.
Disposed outwardly of the upper and lower face plates, 92 , 93 , respectively, are a number of pulleys. Specifically, the preferred embodiment contemplates of use of a tail pulley 55 , a front drive pulley 75 and a plurality of belt idler pulleys 65 , the idler pulleys 65 being linearly disposed between the tail pulley 55 and the front drive pulley 75 . See FIG. 2 . Two sets of pulleys are provided, one set disposed immediately above the other. Each idler pulley 65 , though identical in function, is configured slightly differently from the others as will become further apparent later in this detailed description.
The tail pulley 55 is mounted to the leading rod portion 51 of a tail pulley eccentric 50 . See FIG. 7 . The tail pulley 55 is mounted to the rod portion 51 by means of two bearings 54 and a tension pin 61 . The tail pulley eccentric 50 includes an offset rod portion 52 which projects opposite the forward rod portion 51 of the tail pulley eccentric 50 . The purpose of the tail pulley eccentric 50 is to provide the user of the packaging machine 10 with the ability to quickly and easily move the tail pulley 55 relative to the side seal assembly 20 , one tail pulley 55 being mounted to one side of the upper face plate 92 and another being mounted to the same side of the lower face plate 93 . See FIGS. 2 and 8. The tail pulley eccentric 50 is spring-loaded by virtue of a torsion spring 58 and a tail pulley clip 59 . The tail pulley eccentric 50 is moveable by means of a tail pulley knob assembly 53 which is disposed to the back side of either the top or bottom back plates 90 , 91 , with a collar 62 disposed therebetween. The tail pulley 55 also includes a first belt recess 57 and a second belt recess 56 , the latter of which is tapered.
The side sealer assembly 20 includes a front drive pulley 75 which is similarly mounted to and through the seal frame upper plates 90 , 92 and another drive pulley 75 mounted to the lower plates 91 , 93 by means of a drive shaft 71 . The drive shaft 71 and the drive pulley are each keyed to receive a drive line key 72 therewithin. See FIGS. 2 and 9. To the rear, or backside, of the upper and lower back plates 92 , 93 , respectively, the drive shaft 71 is configured with a pair of drive sprockets 78 , 79 , each of which is also keyed for receiving a second drive line key 74 . While the preferred embodiment contemplates the use of a conventional chain for engagement with and driving of the sprockets 78 , 79 , such is not a limitation of the present invention and the precise drive mechanism can be varied without deviating from the scope of the invention. The drive pulley 75 includes a first belt recess 77 and a second tapered belt recess 76 . It should be noted that the taper of the belt recess 76 of the drive pulley 75 is opposite that taper which is machined into the second belt recess 56 of the tail pulley 55 . The purpose of this will become further apparent later.
Linearly disposed between each front drive pulley 75 and each tail pulley 55 are a number of similarly configured belt idler pulleys 65 . In the preferred embodiment, five such idler pulleys 65 are provided. See FIG. 2 . Each idler pulley 65 includes a first belt recess 67 , a second belt recess 66 and a central hot wire clearance recess 69 . See FIGS. 10 and 11. This central recess 69 is cut relatively deeper into the idler pulley 65 than are the other belt recesses 66 , 67 . The purpose of this is to allow each idler pulley 65 to clear the hot wire 40 which lies between the traveling belts. See FIG. 17 . Each idler pulley 65 is rotatable about and mounted on a shoulder screw 60 by means of a pair of bearings 63 . Disposed between those bearings 63 and the belt idler pulley 65 are a pair of idler pulley insulators 64 . The idler pulley insulators 64 are electrically nonconductive, the purpose of which is to prevent a short to the side seal assembly 20 in flue event of unintentional contact between the hot wire 40 and any one or more of the idler pulleys 65 . The shoulder screw 60 is secured to the rear of the seal frame back plates 90 , 91 and the idler pulley is spaced away from the front of the face plates 92 , 93 by use of a bushing 68 . In the preferred embodiment, the first belt recess 67 of each idler pulley 65 is colinear. That is, a continuous belt 80 traveling along one side of them is held in a straight line and the continuous belt 80 overall is held, in the shape of an elongated oval, in a vertical plane. Such is not the case with the second belt recess 66 of each idler pulley 65 . In the preferred embodiment, the pulleys 65 are collinear and the path formed by the second belt recesses 66 is also collinear, but the plane of the belt 81 , though vertical, diverges away from the plane formed by the belt 80 held within the first belt recess 67 at an angle B as shown in FIG. 12 . Similarly, the distance from the innermost edge of the second belt recess 67 to the innermost edge of the idler pulley 65 decreases from X to Y along the continuum shown in FIG. 12 as well. In this regard, see also FIG. 17 which shows the divergence between the belts 80 , 81 as described above.
The side sealer assembly 20 of the present invention also includes a hot wire 40 which is functionally adapted to cut and weld adjacent layers of thermoplastic film 1 as they pass by it. A stationary wire mounting block 37 and a pivoting wire mounting block 38 are provided. The stationary wire mounting block 37 is mounted above and just inside the tail pulley 55 along the seal frame upper face plate 92 . Similarly, the pivoting wire mounting block 38 is pivotally mounted to the seal frame upper face plate 92 above and just inside the front drive pulley 75 . In the preferred embodiment, the direction of article 8 travel relative to the side sealer assembly 20 is from the direction of the stationary wire mounting block 37 and towards the pivoting wire mounting block 38 for reasons which will be explained later. The stationary wire mounting block 37 is electrically isolated from a charge which is provided by an electrical wire 31 connected to an internal wire assembly clamp 44 by means of a phenolic insulating sleeve 33 . The bottommost portion of the wire assembly clamp 44 is further electrically isolated by virtue of a phenolic washer 43 . The wire assembly clamp 44 includes an internal bore 46 which is machined at a predetermined depth. The internal bore 46 is functionally adapted to receive one lead end 41 of the hot wire 40 . See FIG. 14 . Similarly, the pivoting wire mounting block 38 is electrically isolated from a charge which is provided by an electrical wire 31 connected to an internal wire assembly clamp 45 by means of a phenolic insulating sleeve 33 . The bottommost portion of the wire assembly clamp 45 is further electrically isolated by virtue of a phenolic washer 43 . The wire assembly clamp 45 includes an internal bore 47 which is machined at a predetermined depth and is functionally adapted to receive a second lead end 42 of the hot wire 40 . See FIG. 15 . In the preferred embodiment, the depth of the bore 46 of the stationary wire clamp 44 is 1.00 in. whereas the depth of the bore 47 of the pivotal wire clamp 45 is 0.75 in. In this fashion, a stock wire 40 having lead ends 41 , 42 which are 2.50 in. long drops about 0.25 in. in a run of about 8.125 in., or at an angle WV as shown in FIG. 16 . Fine adjustment of the wire ends 41 , 42 may be accomplished by use of side bolts 49 . See
FIG. 13 . Also in the preferred embodiment, the wire 40 diverges at an angle WH as shown in FIG. 17, which divergence is about 0.32 in. over the 8.125 in. run mentioned above. This divergence is at an angle WV relative to the path of the forwardly disposed belts 80 , 82 shown in FIG. 2 B.
The pivoting mounting block 38 is spring-loaded by virtue of a torsion spring 36 and a wire tensioner collar 35 , both of which are disposed between the seal frame upper back and face plates 90 , 92 , respectively. The mounting block 38 is movable by means of a knob assembly 39 which is attached to one side of the block 38 . In this fashion, rotation of the block 38 releases tension of the wire 40 and allows quick and easy removal of the wire ends 41 , 42 from the wire assembly clamps 44 , 45 .
As previously alluded to, the arrangement of a front drive pulley 75 , a tail pulley 55 and the belt idler pulleys 65 which are disposed between them is duplicated along the lower face plate 93 of the side sealer assembly 20 . The size, shape and configuration of each pulley is effectively mirrored in substantially vertical alignment with its upper face plate counterpart. The pulleys may also be slightly offset to effectively create a greater area of belt surface contact between upper and lower cooperating pulleys. As they lie in a vertical plane extending from the front drive pulley 75 to the tail pulley 55 , the pulleys 55 , 65 , 75 which are attached to the seal frame upper face plate 92 are slightly disposed outwardly relative to their counterparts in the seal frame lower face plate 93 . As discussed earlier, this is the result of machining to the bottom seal frame bearings 97 , 99 by 0.046 in. This is a very important distinctive feature over prior art in that it allows the cooperating V belts 80 , 82 and 81 , 83 which have a meshing-teeth configuration to engage each other in a meshing fashion. More specifically, this feature allows the cooperating V belts 80 , 82 and 81 , 83 to firmly grasp the edge 6 of the thermoplastic film 1 . See FIG. 2 A. Slippage is completely eliminated and distortion of the film 1 is minimized. This results in an extremely smooth and consistent weld along the film edge 6 . See FIG. 2 B. The divergence of the belt paths, i.e. top inner belt 81 away from top outer belt 80 and bottom inner belt 83 away from bottom outer belt 82 , also results in a positive 16 withdrawal of the trimmed post-welding edge away from the side sealed article 8 . Vertical movement of each set of pulleys towards or away from each other is accomplished by use of an air cylinder 16 . See FIGS. 5 and 6. In the preferred embodiment, the bottom set of pulleys which are attached to the seal frame lower plates 91 , 93 are moveable vertically by means of an elevational screw 18 which sets the height of the seal assembly 20 for optimum position relative to the size of the article 8 . Actuation of the air cylinder 16 one way separates the upper and lower pulley and belt assemblies so as to allow the leading edge 6 of the film to be inserted between the belts 80 , 81 , 82 , 83 . Actuation of the air cylinder 16 another way closes the belts 80 , 81 , 82 , 83 towards one another, the force of the cylinder 16 being dampened by means of a dampening spring 17 .
Referring now to FIGS. 18 and 19, the details of the end sealer, generally identified 30 , are illustrated. In particular, an end sealer frame 7 is provided which supports a pair of vertically disposed elevation screws 35 . Each elevation screw 35 is rotatable about a vertical axis by means of a drive wheel 29 which, when rotated, turns a horizontally disposed drive bar 32 and a pair of elevation drive gear assemblies 34 . A rocker pivot 36 is movable along the vertical flight of the elevation screw 35 so as to orient a rocker pivot 36 at the desired center point of the assembly 30 relative to the article 8 to be sealed. A rocker 16 is rotatably attached to the rocker pivot 36 and an upper arm 17 and a lower arm 18 are also provided. The upper and lower arms 17 , 18 , respectively, are likewise rotatably mounted at one end to the rocker 16 . The opposite end of the upper arm 17 is rotatably attached to a top seal bar assembly 47 . Similarly, the opposite end of the lower arm 18 is rotatably attached to a bottom seal bar assembly 87 . The top seal bar assembly 47 includes a top seal bar 48 and the bottom seal bar assembly 87 includes a bottom seal bar 88 , the top and bottom seal bars 48 , 88 , respectively, being functionally adapted to cooperate in the end sealing of the leading edge of the thermoplastic film 1 which approaches the end seal assembly 30 . The bottom seal bar assembly 87 is movable actuated by means of an air cylinder 9 which is mounted within the frame 7 .
In operation, the position of the side sealer assembly 20 and of the end sealer assembly 30 are adjusted to accommodate the size of the article 8 which is to be packaged. The article 8 enters the film envelope 1 with the adjacent film edges 4 , 5 overlaying one another. The film edges 4 , 5 enter the side sealer assembly 20 at the point where the cooperating tail pulleys 55 are situated. Note that the tail pulleys 55 are somewhat separated to allow for some fluctuation in the film 1 positioning. See FIG. 2 . As the film 1 advances, the adjacent film edges 45 are firmly grasped within the teeth 86 and grooves 85 of the outwardly disposed belts 80 , 82 and the inwardly disposed belts 81 , 83 of the side sealer assembly 20 . See FIG. 2 A. As the film 1 continues to be advanced, the diverging sets of belts 80 , 82 and 81 , 83 pull and stretch the film 1 therebetween. As this is occurring, the film begins to enter the fusion area F of the hot wire 40 . See FIG. 16 . This fusion area F is the point generally at which the wire 40 descends below the horizontal plane of film 1 which is belt captured. The heat from the hot wire 40 creates a weld 19 along the film edge closest to the outwardly disposed belts 80 , 82 , which weld 19 is the final side weld for the article 8 . A second weld 39 is created along the film edge closest to the inwardly disposed belts 81 , 83 and which is being pulled away from the first weld 19 by virtue of the divergence of the belts previously described. The quality of the final weld 19 which travels along with the article 8 is preserved by virtue of the divergence of the wire 40 away from the weld 19 also as previously described. As the side sealed article 8 continues, the air cylinder 9 of the end sealer assembly 30 is actuated to move the bottom seal bar assembly 87 upwardly and, by virtue of the rocker 16 and rocker arms 17 , 18 , the top seal bar assembly 47 downwardly to effect an end seal between the top and bottom seal bars 47 , 87 , respectively. The article 8 continues to advance and the end sealer assembly 30 is again actuated to end seal the trailing edge of the plastic encased article 8 . If, during this process, a belt 80 , 81 , 82 , 83 or wire 40 needs to be replaced, the non-tool movement of one of the tail pulleys 55 or the non-tool pivoting of the wire mounting block 38 quickly and easily allows the insertion of the replacement part without any need to readjust or realign the side sealer assembly 20 .
From the foregoing description of the illustrative embodiment of the invention set forth herein, it will be apparent that there has been provided a new and useful method and apparatus for securely grasping and advancing the adjacent layers of thermoplastic film through the side sealing mechanism of a packaging machine; which maintains the integrity of the heat-induced weld which is created at the side sealing mechanism and at the end sealing mechanism of the packaging machine; and which makes the side sealing mechanism an apparatus in which the consumables utilized within the side sealing mechanism can be maintained or replaced by the user without the need for tools or special post-replacement adjustments.
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A method and apparatus for grasping and advancing adjacent layers of thermoplastic film through the side sealing mechanism of a packaging machine includes a plurality of belts which travel about two sets of cooperating pulleys. Each pulley has two circumferential belt grooves defined within it, each belt groove being functionally adapted to allow the travel of a belt along it. A first line of travel is defined along a path which is parallel with the line of travel for articles moving along the wrapping machine. The second line of travel diverges away at a slight angle. The belts are truncated V-belts, the “truncated V” portion of the belts being disposed outwardly of the pulleys. Each set of pulleys is offset such that the belts cooperate in tooth-meshing fashion. A tail pulley of each set is mounted in an offset cam fashion and is spring loaded to apply tension to the belts. Disposed between the belt paths is a hot wire assembly having a similarly longitudinally diverging hot wire. The hot wire assembly utilizes one mounting block which is stationary and another which is rotatable. The mounting blocks are provided with means for allowing insertion of hot wire end connectors at a predetermined depth. An end sealing apparatus includes means for adjusting the end seal location relative to the vertical height of the article to be wrapped.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention generally relates to input/output devices and, more particularly, relates to input/output devices for controlling input/output in a separate-type input/output (hereinafter referred to as "I/O") system and an operating method thereof.
2. Description of the Background Art
There are a separate-type I/O system (I/O mapped I/O system) and a memory mapped I/O system in input/output systems of microprocessors. FIG. 10 shows an address space in an I/O mapped I/O system and FIG. 11 shows an address space in a memory mapped I/O system.
As shown in FIG. 10, memories are arranged in a memory space and input/output devices (hereinafter referred to as "I/O devices") are arranged in an I/O space in the I/O mapped I/O system. As shown in FIG. 11, I/O devices are arranged in a part of the region on the memory space in the memory mapped I/O system.
FIG. 12 is a block diagram showing a structure of an I/O mapped I/O system containing conventional I/O devices.
I/O devices 100 and memories 300 are connected to a central processing unit (hereinafter referred to as "CPU") 200 through a data bus DB, an address bus AB and a control bus CB. An identification signal M/I supplied from CPU200 is applied to a decoder 400 through an inverter G4. A plurality of output signals of decoder 400 are supplied to I/O devices 100 as chip select signals CS. An identification signal M/I supplied from CPU200 is applied to a decoder 500. A plurality of output signals of decoder 500 are supplied to memories 300 as chip select signals CS, respectively.
Address signals A15-A4 are supplied to decoder 400 and address signals A3-A0 are supplied to I/O devices 100. Address signals A19-A10 are supplied to decoder 500 and address signals A9-A0 are supplied to memories 300. Addresses within the I/O space designated by the address signals A15-A0 are thereby assigned to I/O devices 100, and addresses within the memory space designated by the address signals A19-A0 are assigned to memories 300.
The identification signal M/I is used for identifying whether address signals on address bus AB indicate an address on the I/O space or an address on the memory space. Either of decoder 400 and decoder 500 is activated in response to the identification signal M/I. The output signal of decoder 400 activates any one of I/O devices 100. The output signal of decoder 500 activates any one of memories 300.
An external equipment such as a printer, a keyboard, and a communication line is connected to I/O devices 100. Since the operation speed of the external equipment is normally different from that of CPU200, each of I/O devices 100 has a register for temporarily storing data to be transmitted to the external equipment and data received from the external equipment. Each of I/O devices 100 functions as an interface between CPU200 and the external equipment.
Data supplied from CPU200 or data read out from memories 300 through CPU200 is transmitted to the registers within I/O devices 100 through data bus DB and temporarily stored therein. The stored data is transmitted to the external equipment.
Data received from the external equipment is temporarily stored in the registers within I/O devices 100. The stored data is transmitted to CPU200 through data bus DB or to memories 300 through CPU200. I/O devices 100 are controlled by a control signal supplied from CPU200 through control bus CB.
It is necessary to increase the storage capacity of the register included in each of I/O devices 100 in order to increase the amount of data to be inputted to/outputted from the external equipment in the I/O mapped I/O system as stated above. The I/O space, however, is generally smaller than the memory space.
Additionally, even if the I/O space is large, the software thereof becomes complicated in order to access the large I/O space.
Furthermore, if the storage capacity of the registers within I/O devices 100 is small, when a large amount of data is to be transmitted to the external equipment, the data needs to be transmitted many times from CPU200 or memories 300 through data bus DB. Data bus DB cannot be used for other processing during the data transmission.
SUMMARY OF THE INVENTION
An object of the present invention is to improve the processing efficiency in an I/O mapped I/O system.
Another object of the present invention is to provide input/output devices and an operating method thereof in which a large amount of data can be inputted to/outputted from an external equipment by simple processing without occupying a data bus for a long period of time in an I/O mapped I/O system even if the I/O space is small.
Still another object of the present invention is to make it possible to simplify a software for accessing the I/O space in an I/O mapped I/O system.
An input/output device according to the present invention includes a storage device to which addresses on the memory space are assigned, a control device to which addresses on the I/O space are assigned, and a designation signal receiving circuit for receiving a designation signal for designating whether an address signal supplied through a common address bus indicates an address on the memory space or an address on the I/O space. The storage device stores data to be transmitted to an external equipment or data received from the external equipment. The control device includes a holding device for holding control data and controls reading of data to be transmitted to the external equipment from the storage device and writing of data received from the external equipment in the storage device in response to the control data held in the holding circuit. The storage device and the control device are selectively activated in response to a designation signal.
When a designation signal designates the memory space, the storage device is activated. The transmission data is written into the storage device or the reception data stored in the storage device is read out in response to an address signal supplied from the central processing unit through the address bus.
When the designation signal designates the I/O space, the control device is activated. Control data is stored in the holding device within the control device in response to an address signal supplied from the central processing unit through the address bus. The control device reads out transmission data from the storage device and transmits the same to the external equipment or writes the reception data supplied from the external equipment into the storage device based on the control data.
In the input/output device according to the present invention, as the storage device for temporarily storing the transmission data and the reception data is located in the memory space, a large amount of data can be inputted to/outputted from the external equipment even if the I/O space is small.
As transmission/reception of data between the storage device and the external equipment can be controlled by the control data held in the holding device within the control device, the software is made simple.
Furthermore, since the data bus is released after the control data is held in the holding device within the control device, the time period when the data bus is occupied is shortened.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing a structure of an I/O mapped I/O system employing I/O devices according to one embodiment of the present invention.
FIG. 2 is a block diagram showing a structure of an I/O device according to the embodiment.
FIG. 3 is a diagram showing an address space in the I/O mapped I/O system in FIG. 1.
FIG. 4 is a block diagram showing the structure of a transmission reception control circuit included in the I/O device of FIG. 2.
FIG. 5 is a block diagram showing the structure of a first register included in FIG. 4.
FIG. 6 is a block diagram showing the structure of the decoder shown in FIG. 1.
FIG. 7 is a diagram showing in detail the structure of the decoder of FIG. 6.
FIG. 8 is a flow chart showing a transmitting operation by the I/O device in the embodiment.
FIG. 9 is a flow chart showing a receiving operation by the I/O device in the embodiment.
FIG. 10 is a diagram showing an address space in an I/O mapped I/O system.
FIG. 11 is a diagram showing an address space in a memory mapped I/O system.
FIG. 12 is a block diagram showing the structure of a conventional I/O mapped I/O system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram showing the structure of an I/O mapped I/O system employing input/output devices (hereinafter referred to as "I/O devices") according to one embodiment of the present invention.
Each of I/O devices 1 includes a semiconductor integrated circuit. The plurality of I/O devices 1 and a memory 6 is connected to a CPU2 through a data bus DB, an address bus AB and a control bus CB. An identification signal M/I is supplied to a decoder 3 through one control line included in control bus CB. Address signals A19-A4 are applied to decoder 3. Address signals A11-A0 are supplied to each of I/O devices 1 and address signals A19-A0 are supplied to memory 6.
An external equipment such as a printer 4, a keyboard 5 is connected to each of I/O devices 1. Communication lines or other external equipment may be connected to each of I/O devices 1.
Either of decoder 3 and memory 6 is activated in response to the identification signal M/I. Decoder 3 decodes the address signals A19-A4 and supplies a chip select signal CS to any one of the plurality of I/O devices 1. Each of I/O devices 1 is activated in response to the chip select signal CS.
FIG. 2 is a block diagram showing the structure of I/O device 1.
I/O device 1 includes a memory 10 for storing transmission data to the external equipment and reception data from the external equipment, a data selector 20, an address selector 30, a transmission reception control circuit 40 for controlling the transmitting operation and the receiving operation, a reception detecting circuit 50, a bus interface unit 60 and a clock generator 70.
Bus interface unit 60 is connected to a data bus DB, an address bus AB and a control bus CB. A chip select signal CS is supplied to bus interface unit 60 from decoder 3 (see FIG. 1). Address signals A11-A0 are supplied to address selector 30 from bus interface unit 60 and address signals A3 to A0 are supplied to transmission reception control circuit 40 from bus interface unit 60.
Bus interface unit 60 generates an identification signal M/I, a write signal WR and a read signal RD in response to a control signal supplied through control bus CB. The identification signal M/I, the write signal WR and the read signal RD are supplied to memory 10 and transmission reception control circuit 40.
Transmission reception control circuit 40 supplies address signals A11-A0 to address selector 30 at the time of transmitting and receiving data. Address selector 30 selects either one of the address signals A11-A0 supplied from bus interface unit 60 and the address signals a11-a0 supplied from transmission reception control circuit 40 and supplies the same to memory 10 in response to the control signal from transmission reception control circuit 40.
Data selector 20 and transmission reception control circuit 40 are connected to bus interface unit 60 through data bus DB. Data selector 20 is also connected to the external equipment through a data transmission path TP. Data selector 20 selects either of data bus DB and data transmission path TP and connects the same to memory 10 in response to the control signal from transmission reception control circuit 40.
Reception detecting circuit 50 detects that data is transmitted from the external equipment through data transmission path TP and supplies a detection signal DET to transmission reception control circuit 40. Transmission reception control Circuit 40 generates a transmission instruction signal TR instructing to transmit data and a reception instruction signal RE instructing to receive data and supplies the same to address selector 30 and data selector 20.
Clock generator 70 externally receives a system clock signal CK and generates an internal clock signal iCK for controlling the timing of each of internal circuits.
FIG. 3 is a diagram showing the memory space in the system of FIG. 1. Transmission reception control circuit 40 within I/O device 1 is located in the I/O space and memory 10 within I/O device 1 is located in a part of the region within the memory space. Memory 6 shown in FIG. 1 is located in the other region of the memory space.
In FIG. 2, an address on the memory space is designated by the address signals A11-A0 supplied to address selector 30. An address on the I/O space is designated by the address signals A3-A0 supplied to transmission reception control circuit 40. Whether the address signals A11-A0 on address bus AB indicate an address on the memory space or an address on the I/O space is identified by the identification signal M/I.
FIG. 4 is a diagram showing in detail the structure of transmission reception control circuit 40.
Transmission reception control circuit 40 includes a decoder 41, first to sixth registers R1-R6, first and second counters CT1, CT2, adders 42, 44, comparators 43, 45 and an OR gate 46.
Decoder 41 is activated by the identification signal M/I, decodes the address signals A3-A0, and activates any one of the first to sixth registers R1-R6.
The structure of the first register R1 is shown in FIG. 5. One output signal of decoder 41 is supplied to a select terminal SEL of the first register R1. A write signal WR and a read signal RD are supplied to a write control terminal WRITE and a read control terminal READ of the first register R1, respectively. A data input terminal DI and a data output terminal DO of the first register R1 are connected to data bus DB. The structures of the second to sixth registers R2-R6 are the same as that shown in FIG. 5.
The output signal of decoder 41, the write signal WR, the read signal RD and data bus DB are omitted in FIG. 4 in order to simplify the figure.
FIG. 6 is a block diagram showing the structure of decoder 3 shown in FIG. 1.
Decoder 3 includes a decoder for the memory space 31, a decoder for the I/O space 32 and a combination circuit 33. The identification signal M/I is supplied to the chip select terminal CS of memory space decoder 31. The identification signal M/I is supplied to the chip select terminal CS of I/O space decoder 32 through an inverter GO. The address signals A19-A12 are supplied to memory space decoder 31 and the address signals A15-A4 are supplied to I/O space decoder 32.
Combination circuit 33 applies a chip select signal CS to any one of the plurality of I/O devices 1 in response to an output signal of memory space decoder 31 and an output signal of I/O space decoder 32.
FIG. 7 shows the structures of memory space decoder 31, I/O space decoder 32 and combination circuit 33.
Memory space decoder 31 includes a plurality of AND gates G1. An identification signal M/I and address signals A19-A12 or inverted signals thereof are supplied to each of AND gates G1. I/O space decoder 32 includes a plurality of AND gates G2. An inverted signal M/I of the identification signal M/I and address signals A15-A4 or inverted signals thereof are supplied to each of AND gates G2.
Combination circuit 33 includes a plurality of OR gates G3. An output signal of one AND gate G1 in memory space decoder 31 and an output signal of one AND gate G2 in I/O space decoder 32 are supplied to each of OR gates G3. An output signal of each of OR gates G3 is a chip select signal CS.
The operation of I/O devices 1 will now be described with reference to FIGS. 1 and 2.
Firstly, a description will be made of the operation of writing transmission data into memory 10 within I/O device 1 from CPU2. In this case, the identification signal M/I designates the memory space. CPU2 supplies transmission data to data bus DB. Data selector 20 supplies the transmission data of data bus DB to memory 10. Address selector 30 applies the address signals A11-A0 to memory 10. As a result, the transmission data is written into the address designated by the address signals A1-A0.
The operation of reading the reception data stored in memory 10 will now be described. In this case as well, the identification signal M/I designates the memory space. Address selector 30 supplies the address signals A11-A0 to memory 10. As a result, reception data is read out from the address designated by the address signals A11-A0. Data selector 20 provides the reception data read out from memory 10 to data bus DB. The reception data on data bus DB is transmitted to CPU2.
The operation of transmitting data from memory 10 within I/O device 1 to an external equipment will now be described with reference to FIGS. 4 and 8.
Firstly, transmission data is written in memory 10 within I/O device 1 from CPU2 by the operation stated above (step S1).
Then, the identification signal M/I designates the I/O space. At first, data representing a leading address is written into the second register R2 (see FIG. 4) within transmission reception control circuit 40 from CPU2 through data bus DB (step S2). Data representing the number of bytes is written into the third register R3 from CPU2 through data bus DB (step S3). Furthermore, a transmission request command is written into the first register R1 from CPU2 through data bus DB (step S4). As a result, a transmission instruction signal TR is supplied from register R1.
A counting operation by a counter CT1 is initiated after the contents of the first counter CT1 are reset in response to the transmission instruction signal TR (step S5). Adder 42 adds the count data of counter CT1 to data representing the leading address held in the second register R2 and supplies the result as address signals a11-a0 (step S6). The address signals a11-a0 are provided to memory 10 by address selector 30 (see FIG. 2). As a result, transmission data is read out from memory 10 (step S7).
Data selector 20 transmits the transmission data read out from memory 10 to the external equipment through a data transmission path TP (step S8). Thereafter, the count data of counter CT1 is incremented only by 1 (see FIG. 4) (step S9). Comparator 43 compares the count data of counter CT1 with the data representing the number of bytes held in the third register R3 (step S10). If the count data does not coincide with the data representing the number of bytes, the operations in steps S6-S9 are repeated.
If the count data coincides with the data representing the number of bytes, a coincidence signal EQ is supplied from comparator 43. The coincidence signal EQ is supplied to the first register R1 through OR gate 46 as a reset signal RST. As a result, the contents of the first register R1 are reset (step S11). An output signal of OR gate 46 is applied to CPU2 through bus interface unit 60 as an interruption signal INT (step S12).
A description will now be made of the operation of writing data received from the external equipment into memory 10 with reference to FIG. 9.
At first, a region for reception data is provided within memory 10 in step S21.
Then, the identification signal M/I designates the I/O space. Firstly, data representing the leading address is written into the fourth register R4 shown in FIG. 4 from CPU2 through data bus DB (step S22). Data representing the terminating address is also written into the fifth register R5 from CPU2 through data bus DB (step S23). Furthermore, a reception request command is written into the first register R1 from CPU2 through data bus DB (step S24).
Reception detecting circuit 50 (shown in FIG. 2) detects whether or not the reception data has been supplied to data transmission path TP from the external equipment (step S25). If the reception data has been supplied to data transmission path TP, a detection signal DET is generated. After the contents of the second counter CT2 shown in FIG. 4 are reset in response to the detection signal DET, the counting operation by counter CT2 is started (step S26).
Adder 44 adds the count data of counter CT2 to data representing the leading address held in the fourth register R4 and supplies the result as address signals a11-a0 (step S27).
Comparator 45 compares the address signals a11-a0 supplied from adder 44 with data representing the terminating address held in the fifth register R5 (step S28).
If the address signals a11-a0 do not coincide with data representing the terminating address, the address signals a11-a0 are applied to memory 10 by address selector 30 (see FIG. 2). In addition, data selector 20 supplies the reception data on data transmission path TP to memory 10. As a result, the reception data is written into the address designated by the address signals a11-a0 (step S29). Thereafter, the contents of the second counter CT2 are incremented only by 1 (step S30).
Reception detecting circuit 50 detects whether or not the reception data on data transmission path TP is termination data (step S31). If the reception data is not termination data, the operations of steps S27-S30 are repeated.
If the data on data transmission path TP is termination data, the count data of the second counter CT2 is transferred to the sixth register R6 (step S32). The count data transferred to the sixth register R6 is transmitted to CPU2 through data bus DB.
If the address signals a11-a0 coincide with the data representing the terminating address in step S28, a coincidence signal EQ is supplied from comparator 45. The coincidence signal EQ is supplied to the first register R1 through OR gate 46 as a reset signal RST. The contents of the first register R1 are thereby reset (step S33). The output signal of OR gate 46 is applied to CPU2 as an interruption signal INT (step S34).
In the above-mentioned embodiment, as memory 10 is located in the memory space, it is possible to make large the storage capacity of memory 10. Therefore, a large amount of transmission data and reception data can be stored.
Since data for control is held in the first to sixth registers R1-R6 within transmission reception control circuit 40 and transmission data and reception data are not held therein, a large I/O space is not required. Accordingly, even if the I/O space is small, a large amount of data can be inputted to/outputted from the external equipment.
Additionally, as reading of transmission data from memory 10 and writing of reception data to memory 10 are controlled by control data held in the first to sixth registers R1-R6 within transmission reception control circuit 40, the software is made simple.
Furthermore, since data bus DB is released after the control data is transmitted to transmission reception control circuit 40, another processing can be carried out between CPU2 and memory 6 and other equipment.
The identification signal M/I in the embodiment above designates the I/O space when it is at logic "1", for example, and designates the address space when it is at logic "0". Conversely, the identification signal M/I may designate the I/O space when it is at logic "0" and may designate the memory space when it is at logic "1".
Meanwhile, memory 10 includes, for example, a FIFO (First In First Out) memory, and a RAM (Random Access Memory).
It is also possible to arrange each portion within memory 10 in separate spaces.
As stated above, according to the present invention, since the storage device is located in the memory space and the control device is located in the I/O space, a large amount of data can be inputted into/outputted from the external equipment even if the I/O space is small.
Additionally, since reading of data to be transmitted to the external equipment from the storage device and writing of data received from the external equipment into the storage device are carried out in response to control data held in the holding device included in the control device, the software is made simple.
Furthermore, as the data bus is released after the control data is supplied to the holding device included in the control device, the processing efficiency of the system is enhanced.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.
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An I/O device includes a memory and a transmission reception control circuit addresses on the memory space are assigned to the memory. The transmission reception control circuit includes a plurality of registers to which addresses on the I/O space are assigned. The memory stores data to be transmitted to an external equipment or data received from the external equipment. The plurality of registers hold control data. The memory and the transmission reception control circuit are selectively activated in response to an identification signal. The transmission reception control circuit reads out data to be transmitted to the external equipment from the memory or writes data received from the external equipment into the memory in response to the control data held in the plurality of registers.
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[0001] The present invention relates generally to the field of automobile accessories. More particularity, the present invention is directed to a device for improving fuel efficiency of an automobile combustion engine.
DESCRIPTION OF THE RELATED ART
[0002] Since the popularization of automobiles with combustion engines, a variety of devices have been developed to improve their fuel efficiency that is commonly measured with miles traveled per gallon of fuel consumed. For example, proprietary chemicals have been developed as additives to the fuel tank for this purpose. Another example is the ongoing evolution of sophisticated electronic controller for simultaneously monitoring numerous engine operating parameters while performing an electronically-controlled fuel injection into the combustion chamber. Aside from the obvious advantage of cost saving from an increased gas mileage, another potential advantage of fast growing importance is the accompanying reduction of pollutants emitted from an engine with otherwise less complete fuel combustion.
[0003] For further advancement of the art, what is most desirable are fuel saving apparatus that are low cost, compact, easy to install while simultaneously increases gas mileage and reduces pollutant emission.
SUMMARY OF THE INVENTION
[0004] A compact, inline magnetic fuel conditioner is proposed to be interposed along a fuel supply path of a fuel combustion engine for improving fuel efficiency. The magnetic fuel conditioner includes:
an inlet mouth piece for receiving an upstream pre-conditioned fuel flow. an outlet mouth piece for delivering a downstream post-conditioned fuel flow. a hollow device body connected between the inlet mouth piece and the outlet mouth piece. The hollow device body has an internal magnetic manifold for surrounding the fuel flow while simultaneously imparting a magnetic field so as to magnetically condition the molecular structure of the fuel causing a more complete combustion of the fuel in the fuel combustion engine hence improving its fuel efficiency.
[0008] In its simplest form, the magnetic manifold can be implemented with a plurality of permanent magnets for imparting a permanent magnetic field to the fuel. In one embodiment, the permanent magnets are made of a magnetic alloy having at least one component that is a rare earth family element from the periodic table. However, electro magnets can be substituted for these permanent magnets for a similar functionality while providing more controls.
[0009] In another embodiment, the magnetic manifold has a plurality of fuel baffles placed along a first side of the fuel flow. Correspondingly, the plurality of permanent magnets are placed along a second side of the fuel flow such that the resultant imparted magnetic field crosses the path of the fuel flow.
[0010] In yet another embodiment, each of the fuel baffles is shaped into a thin plate oriented perpendicular to the global direction of the fuel flow. Correspondingly, each of the permanent magnets is shaped into another thin plate matching the fuel baffles so as to form two interleaved arrays arranged along the global direction of the fuel flow. The thus formed interleaved arrays cause the local path of the fuel flow to become zigzag-shaped hence increasing the total path length thus dwell time of the fuel flow under magnetic conditioning without increasing the overall length of the magnetic manifold.
[0011] As a refinement for a given total path length of the fuel flow under magnetic conditioning, the spacing between the fuel baffles and the permanent magnets is set to result in a cross-sectional path width of the fuel flow that is:
as small as possible so as to maximize the intensity of interaction between the fuel and the imparted magnetic field. above a minimum allowable value below which the fuel flow rate would otherwise fall below a required level to maintain normal operation of the fuel combustion engine.
[0014] In yet another embodiment to maximize the path length of the fuel flow wherein the conditioning magnetic field is substantially perpendicular to the local direction of the fuel flow:
the magnetization axes of the plurality of permanent magnets are set to be essentially parallel to the global direction of the fuel flow. the plurality of permanent magnets are grouped into magnet pairs and within each magnet pair the magnetization directions of neighboring permanent magnets are set to be parallel to each other. whereas between neighboring magnet pairs the corresponding magnetization directions are set to be opposing each other.
[0018] In yet another embodiment, the magnetic manifold is structured to be essentially cylindrically symmetrical having a cylindrical hull with its cylindrical axis parallel to the global direction of fuel flow. Correspondingly, the plurality of fuel baffles are made to be annular-shaped, placed near the cylindrical surface side of the fuel flow and anchored to the cylindrical hull. The plurality of permanent magnets are made to be disk-shaped, placed near the cylindrical axis side of the fuel flow and anchored to the cylindrical hull.
[0019] To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawing, in which like reference characters designate the same or similar parts throughout the several views, and wherein:
[0021] FIG. 1 illustrates the operating configuration of the magnetic fuel conditioner after its installation along a fuel supply path of a fuel combustion engine for improving fuel efficiency;
[0022] FIG. 2 is an external side view of one embodiment of the magnetic fuel conditioner;
[0023] FIG. 3 is the same as FIG. 2 except with a partial cut-away of the magnetic fuel conditioner body revealing a magnetic manifold inside;
[0024] FIG. 4 is similar to FIG. 3 with a perspective view illustrating an embodiment of the magnetic manifold that is essentially cylindrically symmetrical in structure;
[0025] FIG. 5A illustrates a first transverse cross section of the magnetic manifold;
[0026] FIG. 5B is a partial longitudinal cross section of the magnetic manifold taken along a section from FIG. 5A ;
[0027] FIG. 6A illustrates a second transverse cross section of the magnetic manifold;
[0028] FIG. 6B is a partial longitudinal cross section of the magnetic manifold taken along a section from FIG. 6A ; and
[0029] FIG. 7 is a family of curve-fitted experimental data illustrating the increased gas mileage of test vehicles equipped with the magnetic fuel conditioner of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] In the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will become obvious to those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, materials and components have not been described in detail to avoid unnecessary obscuring aspects of the present invention. The detailed description is presented largely in terms of simplified perspective and sectional views. These descriptions and representations are the means used by those experienced or skilled in the art to concisely and most effectively convey the substance of their work to others skilled in the art.
[0031] Reference herein to “one embodiment” or an “embodiment” means that a particular feature, structure, or characteristics described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Further, the order of process flow representing one or more embodiments of the invention do not inherently indicate any particular order nor imply any limitations of the invention.
[0032] FIG. 1 illustrates an operating configuration of a compact magnetic fuel conditioner 1 of the present invention after its installation along a fuel supply path 5 of a fuel combustion engine 8 for improving fuel efficiency. In the absence of the magnetic fuel conditioner 1 , the traditional fuel supply path 5 includes a serial connection of fuel tank 2 , fuel pump 4 , fuel filter 6 and carburetor plus fuel injector 7 supporting a corresponding flow of fuel 3 from the fuel tank 2 into the fuel combustion engine 8 having a cooling fan 9 . The magnetic fuel conditioner 1 of the present invention is interposed along the fuel supply path 5 and connected between the fuel filter 6 and the carburetor plus fuel injector 7 via an upstream connection point 11 and a downstream connection point 12 . In operation, the magnetic fuel conditioner 1 magnetically conditions the fuel 3 thus causing a more complete combustion of the fuel 3 in the fuel combustion engine 8 hence improving its fuel efficiency. While for an automobile or a motorcycle it is recommended to install the magnetic fuel conditioner upstream of the carburetor along the gas line, for a diesel engine the compact magnetic fuel conditioner should be installed either upstream of the high pressure diesel fuel pump or downstream of the diesel fuel filter along the gas line. Details of the magnetic fuel conditioner 1 internal structures and their resulting magnetic conditioning of the fuel 3 will be presently described.
[0033] FIG. 2 is an external side view of one embodiment of the magnetic fuel conditioner 1 having an inlet mouth piece 20 , fluidically coupled to the upstream connection point 11 of the fuel supply path 5 , for receiving a pre-conditioned fuel flow from the fuel filter 6 . The magnetic fuel conditioner 1 also has an outlet mouth piece 26 , fluidically coupled to the downstream connection point 12 of the fuel supply path 5 , for delivering post-conditioned fuel flow to the carburetor plus fuel injector 7 . A hollow device body 32 is disposed between and in fluidic communication with the inlet mouth piece 20 and the outlet mouth piece 26 for accommodating a fuel flow in between. The fluidic communication with the inlet mouth piece 20 is sealed against leakage with an inlet cover 24 and an inlet end seal 22 . Likewise, the fluidic communication with the outlet mouth piece 26 is sealed against leakage with an outlet cover 30 and an outlet end seal 28 .
[0034] FIG. 3 and FIG. 4 are the same as FIG. 2 except with partial cut-away side and perspective views of the hollow device body 32 revealing a magnetic manifold 36 inside. As seen, the illustrated embodiment of the magnetic manifold 36 is essentially cylindrically symmetrical in structure and is enclosed in a cylindrical hull 34 . The cylindrical axis of the cylindrical hull 34 is parallel to the global direction of fuel flow. Therefore, the magnetic manifold 36 structurally surrounds the fuel flow. To facilitate insertion of the magnetic manifold 36 into the cylindrical hull 34 resulting in a leak-free assembly of the magnetic fuel conditioner 1 , a seal O-ring 38 is provided between the magnetic manifold 36 and the cylindrical hull 34 near the inlet. The magnetic manifold 36 includes a plurality of permanent magnets 40 for imparting a permanent magnetic field to the fuel flow. The permanent magnets 40 are, in this case, disk-shaped, placed near the cylindrical axis side of the fuel flow and are anchored to the cylindrical hull 34 through a corresponding number of permanent magnet anchor 42 .
[0035] FIG. 5A illustrates a first transverse cross section of the magnetic manifold 36 and FIG. 5B is a partial longitudinal cross section of the magnetic manifold 36 taken along a section A-A from FIG. 5A . The plurality of permanent magnets are now illustrated as permanent magnet elements 46 and permanent magnet elements 48 with opposing magnetization directions and this will be presently described in more details. Correspondingly, the permanent magnet elements 46 and 48 together impart a field of magnetic flux 50 in their vicinities. The permanent magnet elements 46 and 48 are affixed to the cylindrical hull 34 via permanent magnet anchors 42 a . While the global direction of the fuel flow 54 is straightforward as indicated, the detailed local paths 52 a and 52 b of the fuel flow inside the magnetic manifold 36 is zigzag-shaped. This is because each of the local paths 52 a and 52 b is surrounded by a plurality of fuel baffles 44 placed along the external side of the fuel flow and the permanent magnet elements 46 and 48 placed along the internal side of the fuel flow. Given the cylindrical symmetry of the magnetic manifold 36 , the fuel baffles 44 are annular-shaped and also anchored to the cylindrical hull 34 . In essence, two interdigitated arrays are formed and arranged along the global direction 54 of the fuel flow while the same interdigitated arrays mechanically deflect the fuel flow periodically. By the same token, the imparted magnetic field, as illustrated with the field of magnetic flux 50 , crosses the local paths 52 a and 52 b of the fuel flow. Notice that, to limit the overall length of the magnetic manifold 36 , each of the fuel baffles 44 is shaped into a thin plate oriented perpendicular to the global direction 54 of the fuel flow and, correspondingly, each of the permanent magnets 46 and 48 is also, as much as possible without losing significant magnetic strength, shaped into another thin plate matching the fuel baffles 44 . As a remark of clarification, the local path 52 a starts at point 58 a and ends at point 58 b , and similarly for the local path 52 b.
[0036] As the magnetic flux 50 crosses the local paths 52 a and 52 b of the fuel flow, the imparted magnetic field causes magnetization thus conditions the molecular structure of the fuel 3 into tiny molecular particles of Carbon-Hydrogen compound. That is, the fuel molecules get magnetized into microscopic particles of the order of nanometer in size. The conjectured underlying mechanism is that the strong magnetic field successively fractures large oil molecules into microscopic, nanometer-sized molecules. These microscopic molecules are further magnetically polarized before they get orderly introduced into the fuel combustion engine 8 chamber for nearly full combustion with increased combustion rate thus fuel utilization efficiency. The now conditioned fuel 3 becomes easier to atomize, easier to combine with Oxygen molecule, easier to evaporate after attaching to the engine chamber wall, thus increasing the combustion efficiency. Additionally, the conditioned fuel 3 speeds up the flame propagation speed and promotes the decomposition of Carbon-Hydrogen compound, ultimately results in a more complete combustion of the fuel oil with greater heat generation. Concomitantly, the conditioned fuel 3 also reduces the exhaustion of harmful materials, raises the energy utilization rate while reducing environmental contamination. It is recognized that the underlying functional mechanism is quite complicated with many unknowns remain to be investigated. Nevertheless, as will also be presently demonstrated, the magnetic fuel conditioner 1 of the present invention has been experimentally proven to function dependably following easy installation and simple utilization.
[0037] Two major design factors warrant special considerations here. The first factor is a sufficient level of magnetic field strength and this is limited by the availability of strong magnetic material. The second factor is the fuel flow route and associated dwell time of the fuel flow under magnetic conditioning. For the first design factor, the permanent magnets 46 and 48 can be made of a magnetic alloy having at least one component that is a rare earth family element from the periodic table. More specifically, they can be made of a Neodymium-Iron-Boron magnetic alloy or a Samarium-Cobalt magnetic alloy. For those skilled in the art, an alternative embodiment of these permanent magnets 46 and 48 can be electromagnets driven by a suitable external electrical supply. The advantage here would be more controls at the expense of added complexity to the magnetic fuel conditioning system. For the second design factor, the aforementioned two interdigitated arrays function to significantly lengthen the local paths 52 a and 52 b of the fuel flow route while simultaneously increasing the exposure of the fuel 3 to the conditioning magnetic flux 50 without significantly increasing the overall length of the magnetic fuel conditioner 1 . This increases the strength and dwell time of interaction between the fuel oil and the conditioning magnetic field. To further increase the interaction between the fuel flow and the magnetic flux 50 hence correspondingly improving the fuel efficiency, the cross-sectional path width 56 a and cross-sectional path width 56 b should preferably be made as small as possible by selecting proper spacings between the permanent magnets 46 , 48 and the fuel baffles 44 and proper spacings between the permanent magnets 46 , 48 and the cylindrical hull 34 . However, for a given total path length of the local path 52 a (and similarly local path 52 b ) under magnetic conditioning, the cross-sectional path width 56 a and 56 b could not be made below a minimum allowable value below which the fuel flow rate would otherwise, due to excessive flow impedance, fall below a required level to maintain normal operation of the fuel combustion engine 8 . In practice, for a total path length of the fuel flow under magnetic conditioning in the range of from about 30 mm to about 200 mm, the cross-sectional path width 56 a and 56 b should be in the range of from about 1 mm to about 1.5 mm.
[0038] Yet another important aspect of the present invention is the orientation of the magnetization direction of the various permanent magnet elements 46 and 48 . As illustrated in FIG. 5B , two pairs of permanent magnets are disposed along the general direction and path of fuel flow. As a result, the magnetization axes of the plurality of permanent magnets 46 and 48 are set to be essentially parallel to the global direction 54 of the fuel flow. Within each pair, for example the pair 46 and 46 , the neighboring magnets are attracted toward each other as their respective neighboring pole faces have opposite polarity. The same applies to the pair 48 and 48 . However, between the two pairs the polarities of the magnets are arranged such that the neighboring magnets are repulsive to each other as their respective neighboring pole faces have the same polarity. This is illustrated with the middle permanent magnets 46 and 48 . This results in a magnetic field distribution, along the global direction 54 of fuel flow, whose magnetization polarity alternates between the two neighboring pairs hence repeatedly intersecting the local path 52 a and local path 52 b of fuel flow route along their entire path within the magnetic fuel conditioner 1 . In this way, the path length of the fuel flow wherein the conditioning magnetic flux 50 is substantially perpendicular to the local direction of the fuel flow gets maximized. This practice is known to further maximize the effectiveness of magnetic conditioning of the fuel 3 .
[0039] FIG. 6A illustrates a second transverse cross section of the magnetic manifold 36 and FIG. 6B is a partial longitudinal cross section of the magnetic manifold 36 taken along a section B-B from FIG. 6A . As described before, the annular-shaped fuel baffles 44 are anchored to the cylindrical hull 34 via a number of fuel baffle anchors 42 b.
[0040] To ascertain its ability to improve the fuel efficiency, the compact magnetic fuel conditioner 1 of the present invention is installed in test vehicles and the test vehicles are driven at constant speed and under various acceleration dynamics for a substantial total distance, their corresponding fuel-consumption are then measured. As an example, compared to otherwise test vehicles without the magnetic fuel conditioner 1 , after the test vehicles with the magnetic fuel conditioner 1 have been driven for 300 kilometers (KM), the following fuel savings were recorded:
suburban area driving: 8.7% metropolitan area driving: 4.5%
Meanwhile, the acceleration dynamics of the test vehicles remains similar to those without the magnetic fuel conditioner 1 of the present invention.
[0041] FIG. 7 is a family of curve-fitted experimental data illustrating the correspondingly increased gas mileage of test vehicles equipped with the magnetic fuel conditioner 1 of the present invention. The horizontal axis is Dwell Time in unit of seconds, the total time the fuel 3 spends inside the magnetic fuel conditioner 1 under magnetic conditioning, approximately between point 58 a and point 58 b of FIG. 5B . The vertical axis is Relative Increase of Gas Mileage in unit of percent (%). The various members of the curve family correspond to their respective conditioning magnetic field strength in unit of Gauss, as imparted by the permanent magnets 46 and 48 of FIG. 5B . While a higher conditioning magnetic field strength clearly provides a correspondingly higher improvement of gas mileage, the maximum magnetic field strength tends to be limited by the material property of the available magnetic alloy making up the permanent magnets. Also, below certain Dwell Time, say around 10 seconds, a high conditioning magnetic field strength alone can not produce significant improvement of gas mileage. On the other hand, above certain Dwell Time, say around 30 seconds, the improvement of gas mileage tends to become saturated with diminishing return. In view of these observations and tradeoffs, in practice a preferred embodiment of the magnetic fuel conditioner 1 is one structured to yield a conditioning magnetic field strength of from about 2000 Gauss to about 2200 Gauss and a dwell time of from about 15 second to about 25 second.
[0042] As described with numerous exemplary embodiments, a compact magnetic fuel conditioner has been described for improving fuel efficiency of a fuel combustion engine. However, for those skilled in this field, these exemplary embodiments can be easily adapted and modified to suit additional applications without departing from the spirit and scope of this invention. For example, for those skilled in the art, it should become clear by now that the structure of the magnetic manifold does not have to be cylindrically symmetrical. The structure can have a square, an elliptical or a rectangular cross section instead. The structure can even be made non-straight such as helical. Thus, it is to be understood that the scope of the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements based upon the same operating principle. The scope of the claims, therefore, should be accorded the broadest interpretations so as to encompass all such modifications and similar arrangements.
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A compact, inline magnetic fuel conditioner is disclosed for improving fuel efficiency of a fuel combustion engine. The fuel conditioner has a magnetic manifold having a built-in magnetic field for interacting thus conditioning the fuel as it flows by. The magnetic field is produced by several pairs of magnets arranged along the fuel path. The magnetic manifold is sealed within a steel hull. The magnetic manifold increases the fuel surface area and its dwell time for magnetization thus improving the fuel combustion efficiency and reducing undesirable emissions to the environment. The resulting fuel saving lies generally in the range of 5% to 15%. Due to its robust operating principle and construction, the compact magnetic fuel conditioner can be deployed under a wide range of weather conditions. Furthermore, the compact magnetic fuel conditioner can be broadly deployed in gasoline engines, diesel engines and industry fuel kilns.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit of and priority to U.S. Provisional Application Ser. No. 60/620,068, filed on Oct. 18, 2004, the entire contents of which being incorporated herein by reference.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates to surgical fasteners and more particularly to surgical fasteners coated with wound treatment materials.
[0004] 2. Description of Related Art
[0005] Generally, coatings for medical devices are useful to create a water absorbent and lubricious coating for surgical instruments, for in-dwelling biomaterials such as stents, screws and internal splints, and for tubing, catheters, wire guides, and the like. Such coatings minimize the trauma of contact of the medical device with tissues and biological fluids. In particular, coatings have been used to provide a slippery and lubricious coating for reducing the coefficient of friction of a surface of a medical device to facilitate movement and maneuverability of the device. Lubricious coatings made from hydrophilic polymers are well-known in the art.
[0006] Medical devices such as surgical fasteners and staples have replaced suturing when joining or anastomosing various body structures, such as, for example, the bowel or bronchus. The surgical stapling devices employed to apply these staples are generally designed to simultaneously cut and seal an extended segment of tissue in a patient, thus vastly reducing the time and risks of such procedures.
[0007] Linear or annular surgical stapling devices are employed by surgeons to sequentially or simultaneously apply one or more linear rows of surgical fasteners, e.g., staples or two-part fasteners, to body tissue for the purpose of joining segments of body tissue together and/or for the creation of anastomosis. Linear surgical stapling devices generally include a pair of jaws or finger-like structures between which body tissue to be joined is placed. When the surgical stapling device is actuated and/or “fired,” firing bars move longitudinally and contact staple drive members in one of the jaws, and surgical staples are pushed through the body tissue and into/against an anvil in the opposite jaw thereby crimping the staples closed. A knife blade may be provided to cut between the rows/lines of staples. Examples of such linear surgical stapling devices are Models “GIA™”, “Endo GIA™” and “Premium Multi-fire TA™” instruments available from United States Surgical, a Division of Tyco Health-Care Group, LP, Norwalk, CT and disclosed in, inter alia, U.S. Pat. No. 5,465,896 to Allen et al., U.S. Pat. No. 6,330,965 to Milliman et al., and U.S. Pat. No. 6,817,508 to Racenet et al., the entire contents of each of which are incorporated herein by reference.
[0008] Annular surgical stapling devices generally include an annular staple cartridge assembly including a plurality of annular rows of staples, typically two, an anvil assembly operatively associated with the annular cartridge assembly, and an annular blade disposed internal of the rows of staples.
[0009] Another type of surgical stapler is an end-to-end anastomosis stapler. An example of such a device is a Model “EEA™” instrument available from United States Surgical, a Division of Tyco Health-Care Group, LP, Norwalk, Conn. and disclosed in, inter alia, U.S. Pat. No. 5,392,979 to Green et al., the entire contents of which is incorporated herein by reference. In general, an end-to-end anastomosis stapler typically places an array of staples into the approximated sections of a patient's bowels or other tubular organs. The resulting anastomosis contains an inverted section of bowel which contains numerous “B” shaped staples to maintain a secure connection between the approximated sections of bowel.
[0010] In addition to the use of surgical staples, sealants, e.g., biological sealants, can be applied to the surgical site to guard against leakage. Typically, the biological sealants are manually applied to the outer surface of the staple line by a physician by spraying on, brushing on, swabbing on, or any combinations thereof. This manual application of biological sealant can lead to non-uniformity of the thickness of sealant across the staple line and/or omitting a portion of the intended coverage area due to inability to see or reach the desired location.
[0011] A need exists for surgical fasteners and the like for delivering wound treatment material to a target surgical site without adding additional steps or complications to the surgical procedure.
SUMMARY
[0012] The present disclosure relates to surgical fasteners and more particularly to surgical fasteners coated with wound treatment materials.
[0013] According to an aspect of the present disclosure, a surgical fastener for use in combination with a surgical fastener applying apparatus is provided. The surgical fastener includes a pair of legs; a crown interconnecting the pair of legs; and a wound treatment material coating at least a portion of the legs and/or crown.
[0014] The wound treatment material may be at least one of an adhesive, a sealant, a hemostat, and a medicament. In an embodiment, the surgical fastener is a staple. In another embodiment, the surgical fastener is a two-part fastener.
[0015] The legs and crown of the surgical fastener may be fabricated from at least one of a non-absorbable and a bio-absorbable material. It is envisioned that the non-absorbable material is at least one of stainless steel and titanium. The bio-absorbable material may be at least one of a homopolymers, copolymers, and a blend of monomers selected from the group consisting of glycolide, glycolic acid, lactide, lactic acid, p-dioxanone, α-caprolactone and trimethylene carbonate. The bio-absorbable material may also be at least one of Polyglycolic Acid (PGA) and Polylactic Acid (PLA).
[0016] The wound treatment material may be a sealant selected from the group consisting of acrylate, methacrylate functional hydrogels in the presence of a biocompatible photoinitiator, alkyl-cyanoacrylates, isocyanate functional macromers with or without amine functional macromers, succinimidyl ester functional macromers with amine or sulfhydryl functional macromers, epoxy functional macromers with amine functional macromers, mixtures of proteins or polypeptides in the presence of aldehyde crosslinkers, Genipin, water-soluble carbodiimides, and anionic polysaccharides in the presence of polyvalent cations.
[0017] The wound treatment material may also be a sealant selected from the group consisting of isocyanate terminated hydrophilic urethane prepolymers derived from organic polyisocyanates and oxyethylene-based diols or polyols; alpha-cyanoacrylate based adhesives; alkyl ester based cyanoacrylate adhesives; adhesives based on biocompatible cross-linked polymers formed from water soluble precursors having electrophilic and nucleophilic groups capable of reacting and cross-linking in situ; two part adhesive systems including those based upon polyalkylene oxide backbones substituted with one or more isocyanate groups in combination with bioabsorbable diamine compounds, or polyalkylene oxide backbones substituted with one or more amine groups in combination with bioabsorbable diisoycanate compounds; and isocyanate terminated hydrophilic urethane prepolymers derived from aromatic diisocyanates and polyols.
[0018] It is envisioned that the wound treatment material is a hemostat selected from the group consisting of fibrin-based, collagen-based, oxidized regenerated cellulose-based and gelatin-based topical hemostats.
[0019] It is contemplated that the wound treatment material is a medicament selected from the group consisting of drugs, enzymes, growth factors, peptides, proteins, pigments, dyes, diagnostic agents or hemostasis agents, monoclonal antibodies, or any other pharmaceutical used in the prevention of stenosis.
[0020] In an embodiment, the wound treatment material may be impregnated into the legs and the crown. In another embodiment, the wound treatment material completely coats the legs and the crown.
[0021] It is envisioned that each leg includes a sharpened distal end. It is further envisioned that the crown is linear or non-linear.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a perspective view of a surgical fastener in accordance with an embodiment of the present disclosure;
[0023] FIG. 2 is a longitudinal cross-sectional view of the surgical fastener of FIG. 1 ;
[0024] FIG. 3 is a longitudinal cross-sectional view of a surgical fastener according to another embodiment of the present disclosure;
[0025] FIG. 4 is a longitudinal cross-sectional view of a surgical fastener according to yet another embodiment of the present disclosure; and
[0026] FIG. 5 is a perspective view of an exemplary two-part fastener constructed in accordance with the present disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0027] Embodiments of the presently disclosed surgical fasteners will now be described in detail with reference to the drawing figures wherein like reference numerals identify similar or identical elements. As used herein and as is traditional, the term “distal” refers to that portion which is farthest from the user while the term “proximal” refers to that portion which is closest to the user.
[0028] With reference to FIGS. 1 and 2 , a surgical fastener, in the form of a surgical staple, is generally shown as 100 . Surgical staples of the present disclosure typically include any metallic staple used to join together tissue parts and/or adjacent tissues. Surgical staples 100 may be made of metal, such as, for example, stainless steel or titanium, or any other material known by one having skill in the art. For example, surgical staples 100 may also be fabricated from bio-absorbable material or the like.
[0029] Bio-absorbable materials used for surgical staples 100 include, and are not limited to, those fabricated from homopolymers, copolymers or blends obtained from one or more monomers selected from the group consisting of glycolide, glycolic acid, lactide, lactic acid, p-dioxanone, α-caprolactone and trimethylene carbonate. Other bio-absorbable materials include and are not limited to, for example, Polyglycolic Acid (PGA) and Polylactic Acid (PLA).
[0030] With continued reference to FIGS. 1 and 2 , surgical staple 100 includes a pair of legs 102 , 104 which are interconnected to one another by a crown or backspan 106 extending between first ends 102 a, 104 a, respectively, thereof. As seen in FIGS. 1 and 2 , crown 106 is substantially perpendicular to legs 102 , 104 . However, it is envisioned that crown 106 may take on any shape and/or form as needed and/or desired and may have any orientation relative to legs 102 , 104 . For example, crown 106 may include two sections which extend angularly from legs 102 , 104 and are connected at an apex (not shown).
[0031] As seen in FIGS. 1 and 2 , respective distal ends 102 b, 104 b of legs 102 , 104 are sharpened to facilitate penetration of legs 102 , 104 into tissue or the like.
[0032] In accordance with the present disclosure, surgical staple 100 is coated with a wound treatment material “W”. It is envisioned that wound treatment material “W” may be applied to the entirety of surgical staple 100 (as seen in FIGS. 1 and 2 ), or may be applied to any specific area of surgical staple 100 that is to come into contact with tissue of the like. For example, wound treatment material “W” may be applied solely to legs 102 , 104 (see FIG. 3 ); solely to one of legs 102 , 104 (not shown); solely to crown 106 (not shown); or any portion thereof. It is further envisioned that wound treatment material “W” may be impregnated into legs 102 , 104 and crown 106 of surgical staple 100 , as seen in FIG. 4 .
[0033] In one embodiment, surgical staples 100 may be fabricated from a bio-absorbable material which is desirably impregnated with wound treatment material “W”. Accordingly, in use, the wound treatment material component of surgical staples 100 may function to retard any bleeding which may occur from the tissue, in the manner of a sealant, and to secure the approximated tissue together, in the manner of an adhesive. The bio-absorbability of surgical staples 100 allows for the at least a portion of surgical staples 100 to be absorbed into the body after a predetermined amount of time. For example, surgical staples 100 may remain in place in the body for approximately 2-3 weeks in order for the anastomosis to sufficiently heal prior to surgical staples 100 being absorbed into the body.
[0034] As mentioned above and as shown in FIG. 3 , it is envisioned that surgical staples 100 may be impregnated with a wound treatment material “W” which is a pre-cured adhesive or sealant. The pre-cured sealant or adhesive will react with the moisture and/or heat of the body tissue to thereby activate the sealing and/or adhesive properties of the sealant or adhesive. It is envisioned that the pre-cured sealant or adhesive may be a hydro-gel or the like.
[0035] It is contemplated that the wound treatment material “W” is any material for joining, healing, sealing or otherwise treating tissue. In a preferred embodiment, the wound treatment material is a bio-compatible sealant, including, and not limited, to sealants which cure upon tissue contact, sealants which cure upon exposure to ultraviolet (UV) light, sealants which are two-part systems which are kept isolated from one another and are combined or any combinations thereof. Any known suitable adhesive may be used. In one embodiment, it is contemplated that such sealants and/or adhesives are curable. For example, sealants may have a cure time of from about 10 to 15 seconds may be used. In preferred embodiments, the sealant and/or adhesive is a bioabsorbable and/or bio-resorbable material. In another embodiment, it is contemplated that a sealant and/or adhesive having a cure time of about 30 seconds may be used. It is further envisioned that wound treatment material “W” may be a pre-cured adhesive or sealant.
[0036] In certain preferred embodiments, the wound treatment material “W” comprises a sealant. Such a sealant is desirably a PEG-based material. Examples of classes of materials useful as the sealant and/or adhesive include acrylate or methacrylate functional hydrogels in the presence of a biocompatible photoinitiator, alkyl-cyanoacrylates, isocyanate functional macromers with or without amine functional macromers, succinimidyl ester functional macromers with amine or sulfhydryl functional macromers, epoxy functional macromers with amine functional macromers, mixtures of proteins or polypeptides in the presence of aldehyde crosslinkers, Genipin, or water-soluble carbodiimides, anionic polysaccharides in the presence of polyvalent cations, etc.
[0037] Some specific materials which may be utilized include isocyanate terminated hydrophilic urethane prepolymers derived from organic polyisocyanates and oxyethylene-based diols or polyols, including those disclosed in U.S. Pat. Nos. 6,702,731 and 6,296,607 and U.S. Published Patent Application No. 2004/0068078; alpha-cyanoacrylate based adhesives including those disclosed in U.S. Pat. No. 6,565,840; alkyl ester based cyanoacrylate adhesives including those disclosed in U.S. Patent No. 6,620,846; adhesives based on biocompatible cross-linked polymers formed from water soluble precursors having electrophilic and nucleophilic groups capable of reacting and cross-linking in situ, including those disclosed in U.S. Pat. No. 6,566,406; two part adhesive systems including those based upon polyalkylene oxide backbones substituted with one or more isocyanate groups in combination with bioabsorbable diamine compounds, or polyalkylene oxide backbones substituted with one or more amine groups in combination with bioabsorbable diisoycanate compounds as disclosed in U.S. Published Patent Application No. 2003/0032734, the contents of which are incorporated by reference herein; and isocyanate terminated hydrophilic urethane prepolymers derived from aromatic diisocyanates and polyols as disclosed in U.S. Published Patent Application No. 2004/0115229, the contents of which are incorporated by reference herein.
[0038] It is envisioned and within the scope of the present disclosure that wound treatment material “W” may include one or a combination of adhesives, hemostats, sealants, or any other tissue or wound-treating material. Surgical biocompatible wound treatment materials “W”, which may be used in accordance with the present disclosure, include adhesives whose function is to attach or hold organs, tissues or structures, sealants to prevent fluid leakage, and hemostats to halt or prevent bleeding. Examples of adhesives which can be employed include protein derived, aldehyde-based adhesive materials, for example, the commercially available albumin/glutaraldehyde materials sold under the trade designation BioGlue™ by Cryolife, Inc., and cyanoacrylate-based materials sold under the trade designations Indermil™ and Derma Bond™ by Tyco Healthcare Group, LP and Ethicon Endosurgery, Inc., respectively. Examples of sealants, which can be employed, include fibrin sealants and collagen-based and synthetic polymer-based tissue sealants. Examples of commercially available sealants are synthetic polyethylene glycol-based, hydrogel materials sold under the trade designation CoSeal™ by Cohesion Technologies and Baxter International, Inc. Examples of hemostat materials, which can be employed, include fibrin-based, collagen-based, oxidized regenerated cellulose-based and gelatin-based topical hemostats, as well as aluminum alum (i.e., ammonium alum or aluminum ammonium sulfate). Examples of commercially available hemostat materials are fibrinogen-thrombin combination materials sold under the trade designations CoStasis™ by Tyco Healthcare Group, LP, and Tisseel™ sold by Baxter International, Inc. Hemostats herein include astringents, e.g., aluminum sulfates, and coagulants. A further example of a hemostat includes “Quick Clot™”, commercially available from Z-Medica, Inc., Newington, Conn..
[0039] The medicament may include one or more medically and/or surgically useful substances such as drugs, enzymes, growth factors, peptides, proteins, dyes, pigments, diagnostic agents or hemostasis agents, monoclonal antibodies, or any other pharmaceutical used in the prevention of stenosis. The medicament may be disposed on structure 100 or impregnated into structure 100 .
[0040] Wound treatment material “W” may include visco-elastic film forming materials, cross-linking reactive agents, and energy curable adhesives. It is envisioned that wound treatment material “W”, and in particular, adhesive may be cured with the application of water and/or glycerin (1, 2, 3, -pranatetriol, also known as glycerol or glycerine) thereto. In this manner, the water and/or glycerin cure the adhesive and hydrate the wound.
[0041] It is further contemplated that wound treatment material “W” may include, for example, compositions and/or compounds which accelerate or beneficially modify the healing process when particles of the composition and/or compound are applied to or exposed to a surgical repair site. For example, the wound treatment material “W” may be a therapeutic agent which will be deposited at the repair site. The therapeutic agent can be chosen for its antimicrobial properties, capability for promoting repair or reconstruction and/or new tissue growth. For example, the wound treatment material “W” may comprise “SilvaSorb™”, commercially available from AcryMed, Inc, Portland, Oreg.. Antimicrobial agents such as broad spectrum antibiotic (gentamycin sulfate, erythromycin or derivatized glycopeptides) which are slowly released into the tissue can be applied in this manner to aid in combating clinical and sub-clinical infections in a tissue repair site. To promote repair and/or tissue growth, wound treatment material “W” may include one or several growth promoting factors, e.g., fibroblast growth factor, bone growth factor, epidermal growth factor, platelet derived growth factor, macrophage derived growth factor, alveolar derived growth factor, monocyte derived growth factor, magainin, and so forth. Some therapeutic indications are: glycerol with tissue or kidney plasminogen activator to cause thrombosis, superoxide dimutase to scavenge tissue damaging free radicals, tumor necrosis factor for cancer therapy or colony stimulating factor and interferon, interleukin-2 or other lymphokine to enhance the immune system.
[0042] It is further envisioned and within the of the present disclosure for wound treatment material “W” to include any microbial agent, analgesic, growth factor, and anti-inflammatory agent known by one having skill in the art or any combination thereof.
[0043] Those skilled in the art will recognize that the successful surface treatment of surgical staple 100 , prior to the application of wound treatment material “W”, may include pre-cleaning surgical staple 100 and controlling the moisture at the surface of surgical staple 100 in order to ensure complete and/or proper coating of surgical staple 100 . Multi-step cleaning and drying operations can therefore be used to provide a clean surface and to control moisture. Once the surface of surgical staple 100 is treated, as described above, a solution containing wound treatment material “W” is applied to the treated surgical staple 100 .
[0044] It is contemplated and within the scope of the present disclosure for any of the surgical staples 100 disclosed herein to be used in connection with linear-type surgical staplers, non-linear-type surgical stapler, annular-type surgical staples, endoscopic-type surgical staplers, skin-type surgical staplers and the like.
[0045] It is further contemplated and within the scope of the present disclosure for any of the surgical staples 100 disclosed herein to have equal length legs, un-equal length legs, a relatively short crown as compared to the length of the legs, a relatively long crown as compared to the length of the legs, a symmetrical transverse cross-sectional profile in at least one of the legs and the crown, and an asymmetrical transverse cross-sectional profile in at least one of the legs and the crown. For example, each leg and/or the crown may have a cross-sectional profile which is polygonal, such as, triangular, rectangular, hexagonal any combination thereof or the like. Moreover, each leg and/or the crown may have a cross-sectional profile which is circular, ovular or the like. It is further envisioned that the crown may be either linear of non-linear.
[0046] It is still further contemplated and within the scope of the present disclosure for any of the surgical staples 100 disclosed herein to include legs which do not lie in the same plane as one another. In other words, one leg and the crown of the surgical staple 100 define a first plane, and the other leg of the surgical staple 100 lies in a second plane which is non-coplanar, or transverse to the first plane.
[0047] As seen in FIG. 5 , a surgical fastener, in the form of a two-part fastener, is generally shown as 200 . The physical structure of an exemplary surgical fastener 200 is shown and described in U.S. Pat. No. 4,534,352, the entire content of which is incorporated herein by reference. Generally, surgical fastener 200 includes a retainer member 210 and fastener member 202 , which has two prongs or legs 204 that are driven through tissue (not shown) to engage apertures 212 in retainer member 210 . Prongs 204 each include a barb 206 attached to a shank 208 .
[0048] In accordance with the present disclosure, surgical fastener 200 , including retainer member 210 and fastener member 202 may be constructed from any of the materials disclosed hereinabove either identically (constructed from the same materials) or uniquely (i.e., constructed from different materials) from one another.
[0049] It should be understood that various changes in form, detail and application of the support structures of the present disclosure may be made without departing from the spirit and scope of the present disclosure.
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The present disclosure relates to surgical fasteners and more particularly to surgical fasteners coated with wound treatment materials. According to an aspect of the present disclosure, a surgical fastener for use in combination with a surgical fastener applying apparatus is provided. The surgical fastener includes a pair of legs; a crown interconnecting the pair of legs; and a wound treatment material coating at least a portion of the legs and crown.
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FIELD OF THE INVENTION
The invention relates to file cabinets or other cabinets with drawers which slide out, and in particular to a safety device and method for preventing multiple drawers from opening simultaneously.
BACKGROUND OF THE INVENTION
It is common for cabinets to have several drawers each of which may be filled with heavy files. When all drawers are closed, the mass of all the drawers is centred, and the file cabinet is very stable. However, when a drawer is pulled open, the weight of the drawer is removed from the centre, and there is a force created on the cabinet which acts away from the centre of mass of the cabinet. So long as there is sufficient weight in the remaining drawers to hold the cabinet vertical, the cabinet will not tip over. However, as more drawers are pulled open, the cabinet becomes increasingly unstable, and the likelihood of tipping increases. Tipping of a heavy file cabinet may cause serious injury to a person standing in front of the cabinet, or may cause damage to the file cabinet and its contents.
Various devices have been proposed to limit the number of drawers which can be open at the same time. For instance, in U.S. Pat. No. 4,272,138 an anti-tip device is disclosed which includes a segmented column consisting of a plurality of longitudinally extending snubber elements axially aligned in end-to-end abutting relation. The column extends adjacent to each drawer and the column, and/or the individual snubber elements are resiliently mounted within the cabinet to permit movement between a central equilibrium position and one of two opposite axially displaced positions. Each drawer carries on its side an activator rail which is disposed at right angles to the column. The tapered end of each activator rail is positioned so as to insinuate itself between two adjacent abutting snubber elements when the respective drawer is opened. The act of activator rail insinuation between adjacent snubber elements causes each of the snubber elements in the column to be displaced from a central equilibrium position to one of the two displaced positions. In their displaced positions, the snubber elements block opening of further drawers. In U.S. Pat. No. 4,637,667, a somewhat similar scheme is proposed in which a locking mechanism is also integrated into the design.
In U.S. Pat. No. 4,239,309 U-shaped hooks are provided on a vertical bar. The hooks engage the drawers and prevent them from opening when the hooks are displaced vertically. When a drawer is opened, a ramp mechanism on the side of the drawer slides the hook bar vertically engaging the remaining drawers, thus preventing any other drawer from opening.
These designs are complex, expensive to produce, and require manufacturing to precise tolerances.
Other designs rely on a set of bars disposed in a vertical channel of fixed length. In Canadian Patent 1,175,875 a set of vertical bars are provided, one of which is moved vertically upon the opening of a drawer such that no more vertical movement of any bar is possible, due to the fixed length of the channel for the bars. The movement of the bars is achieved by an independent cylindrical member disposed between the bars which is rotated by the opening of the drawer. The amount of space occupied between the bars by the member increases in its rotated state. This design depends upon accurate measurement of all the bars such that they all fit exactly in the length of the vertical channel when one drawer is opened. Further, the member must be rotated against the frictional force of both the bars above and below. U.S. Pat. No. 4,355,851 discloses a similar arrangement in which a rotating member engages a wedge disposed between the bars of a fixed length channel and forces the bars to slide until no more vertical play is present. Enough play is allowed such that only a single drawer may be opened. An excessive number of parts and close tolerances are required in both of these designs.
U.S. Pat. No. 4,429,930 has a rotating member which is attached pivotably to bars above and below the member such that rotation of the member causes vertical displacement of the bars. Again, the fixed vertical length of the channel in which the bars are located prevents further rotation of other members. This pivoting member is constructed from two different pieces, and is attached to both the bars above and below the pivot. This leaves little flexibility in the design of the pieces which fit in the channel because they are all physically linked together and complicate manufacture.
SUMMARY OF THE INVENTION
The present invention provides a novel, easily manufactured anti-tip device.
According to a broad aspect, the invention provides an anti-tip device for use in a cabinet, and a cabinet having the anti-tip device mounted therein, the cabinet comprising a housing; two or more drawers in the housing each having a post mounted thereon; a channel mounted in the housing adjacent said drawers, one side of said channel having a discrete opening of predetermined dimensions associated with each adjacent drawer; a bar of predetermined length associated with each adjacent drawer, each bar being slidingly retained in the channel with at least one end movably abutting an end of an adjacent bar, and each bar having a rigid tongue extending through one discrete opening; and a pivot member associated with each drawer having a post retaining channel and an arm, each pivot member being pivotably mounted in the housing such that it has a closed position in which the post of the associated drawer is retained in the post retaining channel and an open position in which said post is free to exit the post retaining channel; wherein opening of a drawer causes its post to engage its post retaining channel urging the pivot member to pivot to its open position, and wherein pivoting of the pivot member causes the arm to pivot in engagement with the tongue of the drawer's associated bar thereby slidingly displacing the bar and facilitating insertion of an end of the arm into the channel between adjacent bars, or between the end of a bar and the end of the channel; and when one pivot member is in its open position allowing opening of the drawer it is associated with, the displacement of tongues associated with other drawers is limited by engagement of the tongues with the periphery of the associated opening, engagement of an end of the associated bar with an abutting end of another bar, or engagement of an end of said bar with the arm of the pivot member which is in its open position, thereby preventing pivoting of the other pivot members and accordingly opening of more than one drawer; the channel can accommodate only one open pivot member or can partially accommodate two or more partially open pivot members, partially open pivot members not permitting the associated drawers from opening, thereby preventing two or more drawers from being opened simultaneously.
The device can be employed with vertically stacked drawers as described below or with horizontally aligned drawers. In the latter case the channel is mounted behind the drawers and the posts configured to interengage with a post retaining channel of a pivot member also mounted behind the drawers.
Flexibility in the design of the components allows the device to be easily integrated into any cabinet. For example, the pivot members may be mounted on the bars, or they may be attached directly to the cabinet housing. The shape and size of the tongues and pivot member arms can be varied and are not required to be within precise tolerance. The post retaining channels can be made wide enough to provide significant tolerance in the engagement and interaction with the posts on the drawers.
DESCRIPTION OF THE DRAWINGS
The invention will be further described by way of example with reference to the drawings in which:
FIG. 1 is a perspective view of a file cabinet;
FIG. 2 is a perspective view of a pivot member forming part of the file cabinet of FIG. 1, the pivot member being shown in the closed position;
FIG. 3 is a perspective view of the pivot member of FIG. 2 in the open position;
FIG. 4 is a side elevation of the pivot member of FIG. 2 in the closed position with the open position shown in phantom;
FIG. 5 shows a pair of pivot members forming part of the file cabinet of FIG. 1 in which the upper pivot member is in the open position and the lower pivot member is in the closed position; and
FIG. 6 shows the pair of pivot members of FIG. 5 in which the upper pivot member is in its closed position and the lower pivot member is in its open position.
DESCRIPTION OF PREFERRED EMBODIMENTS
For convenience, the invention will be described as applied to a four drawer lateral type file cabinet but the invention is not limited to use in such a cabinet.
With reference to FIG. 1, there is shown a lateral type file cabinet 10 having a housing and four drawers 12,14,16,18. The drawers 12,14,16,18 are slidingly mounted within the housing for movement in and out of the housing through conventional mounting means 20. In the illustrated embodiment sliding rails are provided for supporting the drawers.
An anti-tip device is provided on the cabinet 10, and in engagement with the drawers 12,14,16,18. The anti-tip device includes a channel 22 mounted in the housing. The channel 22 may be of any suitable configuration. In the illustrated embodiment the channel has a flat back secured to the right inside 24 surface of the cabinet 10, and two perpendicular walls 26,28. The channel 22 may be constructed from a separate piece of material as illustrated in FIG. 1, or may be integrated into a structural member used to support the drawer mounting means and to provide strength for the cabinet.
In the illustrated embodiment there are four bars 30,32,34,36 slidably located in the channel with at least one end of each bar movably abutting an end of an adjacent bar, the bars shown being approximately square in cross-section so as to fit in the channel. There will always be a number of bars in the channel at least as great as the number of drawers. In the illustrated embodiment, an additional bar 38 is provided for supporting the bottom pivot member, as discussed below. At the bottom of each of the bars (except the bottom bar), a rigid tongue 40,42,44,46 extends out of the channel 22 through a corresponding discrete opening 48,50,52,54 of predetermined dimensions in one of the walls 28 of the channel. The tongues 40,42,44,46 are rectangular in shape, and have an upward slant as they extend away from the bars. This particular shape and angle are not essential however. The combined length of the bars shown (not including the additional bottom bar) extends from the bottom of the bottom discrete opening 54 to beyond the top of the top discrete opening 48. The bars 30,32,34,36,38 are held in the channel 22 either by the drawer mounting means 20, or by separate tabs which cross the channel. Alternatively, the channel could be constructed to self-contain the bars.
Four cams or pivot members 56,58,60,62 are mounted in the housing, one pivot member being mounted in association with each of the drawers. These may be mounted pivotably to the side of the cabinet, or near the top of the each bar except the top bar as illustrated.
The further details of the pivot members 56,58,60,62 will be described with reference to FIG. 2 in which one of the pivot members 58 is shown in its closed position and FIG. 3 which shows a pivot member in its open position. The pivot member 58 is mounted near the top of a bar 34 with a pivot 64 permitting rotation of the member 58 about that pivot. Each pivot member 58 has an arm 66 which extends at approximately the same angle as the tongue 42 on the bar above 32. Each arm has an end which may be a cylindrical sliding member 68 as illustrated, and which has approximately the same width as the bars. A stopper or tab 70 extending in the direction of the sliding member 68 from the arm 66 may be provided to prevent the over-counter-clockwise rotation of the member 58 while it is in its closed position. While the pivot member 58 is in its closed position, the bar above 32 rests on the top of the bar below 34. The tongue 42 of the bar above 32 is protruding from the channel 22 near the bottom of the discrete opening 50. The pivot member 58 also includes a post retaining channel 72 constructed from two walls 74,76 which extend in a direction perpendicular to the side wall of the cabinet. This post retaining channel 72, in engagement with a post 78 to be described below, also prevents over-counter-clockwise rotation of the pivot member 58.
In FIG. 3, the pivot member 58 has been rotated into its open position. In this case, the bar above 32 has been displaced upwards by the sliding member 68 the distance necessary to accommodate the sliding member 68 of the pivot member 58 attached to the bar below 34 in the channel 22. In order to permit pivoting of the sliding member 68 into the channel 22, the rectangular discrete opening 50 is provided in one wall 28 of the channel for each sliding member, as discussed above. In the illustrated embodiment, no opening is provided on the opposite side of the channel. This prevents over-rotation of the pivot member 58 in the clock-wise direction. However, the tab 70 or the top of the bar 34 to which the pivot member 58 is mounted may also serve this purpose. While the pivot member 58 is in its open position, the bar above 32 rests on the sliding member 68 which is now located in the channel 22 directly above the bar 34 upon which it is mounted. The tongue 42 of the bar above 32 is now protruding at the top of the discrete opening 50.
FIG. 4 shows a side elevation of the one of the pivot members 58 in its closed position, and shows a post 78 located in the post retaining channel 72. This post is mounted on the associated drawer as shown in FIG. 1, and as discussed further below. The illustrated post is cylindrical in shape, which is preferred because of the ease with which it can slide. However, posts of other shapes may be used. The open position of the pivot member 58 is shown in phantom showing the cylindrical post 78 leaving the post retaining channel 72. Upon rotation of the pivot member 58, the cylindrical sliding member 68 slides along the surface of the tongue 42 of the bar above 32, and forces the bar above to slide upwards, thereby making room in the vertical channel 22 for the sliding member 68. Although the sliding member 68 is shown with a cylindrical cross section, and the tongue 42 is rectangular in shape, the important feature is that the sliding member can slide against the tongue so as to urge the associated bar out of the way. Thus, other shapes and sizes may easily be utilized for these components.
Each drawer has a post 78 which is permanently installed on one side of the drawer so as to sit in the post retaining channel 72 of a corresponding pivot member 58 when the drawer is in a closed position. When a drawer is moved towards an open position, the post 78 disengages from the post retaining channel 72 of the pivot member 58 and moves out of the cabinet together with the drawer. More particularly, as the post 78 moves with the drawer, it engages the channel wall 76 and thereby urges the pivot member 58 to pivot from its closed position to its open position as shown in phantom in FIG. 4.
Once a single drawer has been opened, the anti-tip device prevents further drawers from being opened. The device also prevents the simultaneous opening of two or more drawers. The manner in which this is accomplished by the illustrated embodiment will be described with reference to FIGS. 5 and 6.
In FIG. 5, two pivot members 58,60 are shown. The top member 58 has an open position, corresponding to an open drawer, while the bottom member 60 has a closed position corresponding to a closed drawer. The post 78 of the open drawer is seen exiting the post retaining channel 72 of the upper pivot member 58, while the post 80 of the closed drawer is seen retained by the post retaining channel 82 of the lower pivot member 60. Also shown are three bars, a lower bar 36, a central bar 34 and an upper bar 32. The lower bar 36 and the central bar 34 have pivot members 60,58 near their tops, while the central bar 34 and the upper bar 32 have tongues 44,42 near their bottoms. The disposition of the sliding member 68 on the pivot member 58 of the central bar 34 in the channel 22 has caused the upper bar 32 to slide upwards, and the tongue 42 of that bar be maintained at or near the top of the corresponding discrete opening 50 in the side of the channel 22. There is very limited room for the upper bar 32 to move any further in the upwards direction since the tongue 42 engages with the top of the discrete opening 50. When a user attempts to pull out the drawer below, this requires the lower pivot member 60 to rotate to free the post 80. For the pivot member 60 to be able to rotate, the central bar 34 must be able to slide vertically upwards to allow the channel 22 to accommodate the arm 84 and sliding member 86 of the lower pivot member 60. This is not possible however, because the sliding member 68 of the pivot member 58 of the central bar 34 is located in the channel 22 against the bottom of the upper bar 32, which can no longer slide upwards, because its tongue 42 is at the top of the discrete opening 50 in the channel 22. Thus the bar below it 34, and all of the other bars below it, are prevented from moving upwards. Because the bars cannot move, the corresponding post retaining channels on the pivot members are held in their closed positions which do not allow the posts of the corresponding drawers to disengage, this disengagement being required for the drawers to open. In summary, the single tongue of the bar above an open pivot member (corresponding to an open drawer) engaging the discrete opening in the channel prevents all drawers below this drawer from being opened.
In FIG. 6, two pivot members 58,60 are shown. The top member 58 has a closed position, corresponding to a closed drawer, while the bottom member 60 has an open position corresponding to an open drawer. The post of the closed drawer 78 is shown retained by the post retaining channel 72 of the upper pivot member 58, while the post 80 of the open drawer is shown exiting the post retaining channel 82 of the lower pivot member 60. As before, also shown is a lower bar 36, a central bar 34, and an upper bar 32. The lower bar 36 and the central bar 34 have pivot members 60,58 near their tops, while the central bar 34 and the upper bar 32 have tongues 44,42 near their bottoms. The disposition of the cylindrical sliding member 86 of the lower pivot member 60 in the channel 22 has caused the central bar 34 and all bars above it including the upper bar 32 to slide upwards, and the tongue 44 of the central bar and all bars above it attain positions at or near the top of the corresponding discrete openings in the side of the channel 22 for the bars. There is no more room for the upper bar 32 to move any further in the upwards direction because the top of the discrete opening 50 in the channel 22 will engage with the tongue 42. Thus, when a user attempts to pull out the drawer above, this requires the upper pivot member 60 to rotate, and requires the upper bar 32 to slide vertically to accommodate the sliding member 68. This is not possible however, because the tongue 42 of the upper bar 32 is already up against the discrete opening 50 in the channel 22, and cannot move any further. The post retaining channels on the pivot members above the open pivot member are held in their closed positions which do not allow the posts on the corresponding drawers to disengage, this disengagement being required for the drawers to open. In summary, the opening of a lower pivot member causes all of the pivot members and tongues above to move vertically such that all of the tongues come close to engaging the upper side of their corresponding openings in the channel, thereby preventing all of the drawers above the open drawer from being opened.
The anti-tip mechanism of the invention, in addition to preventing a second drawer from being open after a first drawer has been opened, also prevents the simultaneous opening of two or more drawers. There is sufficient space in the channel for one completely open pivot member. It is possible that two or more pivot members may be partially open, but the post retaining channels are designed such that they will not allow the corresponding posts to disengage unless fully open. As such, when it is attempted to open two or more drawers simultaneously, no drawers will be allowed to open.
It should be further understood that although in the description the tongues are always described as being at the top or the bottom of the rectangular discrete openings, some limited movement in the tongues and bars may be permitted after a drawer has been opened, so long as the amount of movement is not sufficient to allow rotation of the post retaining channels corresponding to closed drawers to the point that the post of the corresponding drawer can escape its post retaining channel.
In a variant of the principle embodiment described above, a locking mechanism may be added. The lock (not shown) is installed at the top of the anti-tip device. While the lock is open, the bars in the anti-tip device are free to slide as described above. While the lock is closed, the top bar is prevented from sliding, thereby preventing any of the other bars from sliding, and thereby preventing any of the drawers from being opened.
A spring (not shown) may be added between the top of the top bar and the top of the file cabinet to add an element of resiliency to the manner in which the bars slide. This would reduce any clanking noise which may result from the anti-tip device, and would make the operation smoother.
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An anti-tip device is provided for use in cabinets having two or more drawers, for preventing more than one drawer from being opened simultaneously, thereby reducing the likelihood of the cabinet tipping over due to the force of multiple open drawers. The device comprises a series of bars and pivot members disposed within a vertical channel. The pivoting of one of the pivot members to its open position prevents the pivoting of members both above and below the open member. The pivot members engage the drawers of the cabinet such that a drawer may only be opened when its associated pivot member is pivotable to its open position.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. §119(a) the benefit of Korean Patent Application No. 10-2015-0177465 filed in the Korean Intellectual Property Office on Dec. 11, 2015, the entire contents of which are incorporated herein by reference.
BACKGROUND
[0002] (a) Field of the Invention
[0003] The present invention relates to a MEMS resonator, more particularly, to a MEMS resonator maintaining a tuning state without an ongoing application of voltage through a method of controlling rigidity to tune a resonance frequency when a voltage is applied to an actuator to artificially restrain a spring supporting a mass body.
[0004] (b) Description of the Related Art
[0005] In general, a MEMS (Micro-Electro-Mechanical System) technology is used to make micro mechanical structures, such as ultra-high-density integrated circuits, by processing silicon, crystal, or glass.
[0006] The MEMS technology that started through silicon processing techniques can realize mass production of an ultra-small-sized product at low cost by applying semiconductor fine processing technology for structurally repeating processes such as deposition and etching, such that size, cost, and power consumption can be significantly reduced.
[0007] Particularly, the MEMS resonator is widely used in various fields such as an acceleration system, an inertial sensor such as an angular speed system, an RF filter, a mass detecting sensor, and a microlens scanner.
[0008] This MEMS resonator consists of a mass body, a spring, and a damper, and detects conversion coefficients due to a physical amount input from an outside such as amplitude of the mass body and a resonance frequency, that is, resonance characteristics.
[0009] However, the MEMS resonator is defective when its own frequency is changed due to errors or operation environments of a manufacturing process, that is, changes of an external temperature or pressure.
[0010] However, an existing method of tuning the frequency is complicated and costly, and in the electrical tuning type, there is a drawback that an ongoing application voltage is required.
[0011] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
SUMMARY
[0012] A MEMS resonator is configured to tune a resonance frequency by controlling rigidity as a spring connected to a mass body is restrained by applying a voltage to an actuator and maintain a tuning state by a frictional force of a carbon nanotube (CNT) even if the voltage is removed after the tuning is completed.
[0013] In one or a plurality of exemplary embodiments of the present invention, a MEMS resonator includes: a main substrate forming a receiving part at a center of the main substrate; a mass body positioned at a center of the receiving part on the main substrate and having one end part and a center part elastically supported at both sides of the main substrate through a first elastic member and a second elastic member; a driving unit configured at one side of the receiving part on the main substrate and producing a driving torque by a voltage applied to both sides of the one end part of the mass body to move a position of the mass body with respect to the main substrate; and a tuning part including a pair of tuning units provided symmetrically as a pair with respect to the second elastic member, respectively configured at the receiving part by corresponding to both sides of the center part of the mass body, and having a beam member changing a length of the second elastic member by an actuating operation of each tuning unit to control a frequency.
[0014] The tuning unit may include: an auxiliary substrate configured inside the receiving part of the main substrate by corresponding to the center part of the mass body; a first actuator configured in the receiving part between the auxiliary substrate and the main substrate and driving each contact end positioned at both sides with respect to a shuttle positioned at the center of the receiving part depending on an application voltage to control a movement of the shuttle; a second actuator positioned at a rear part of the first actuator in the opposite side of the second elastic member and configured with a driving beam on a plurality of heating lines extending by an application voltage act on the rear end of the shuttle; and a beam member positioned to enable contact with the second elastic member inside the receiving part between the auxiliary substrate and the main substrate and fixed to a front end of the shuttle.
[0015] The front end part of the shuttle may be connected to a third elastic member disposed between the auxiliary substrate and the main substrate.
[0016] The first actuator may include a shuttle positioned at the center of the receiving part between the auxiliary substrate and the main substrate, may be disposed respectively corresponding to the auxiliary substrate and the main substrate at both sides of the shuttle to form a contact end contacting the shuttle at each inner end, and may have a deformation part made of a first beam and a second beam connected to an electrode from the contact end.
[0017] The first beam may be disposed at both sides corresponding to the shuttle, the second beam may be formed with the same thickness outside the first beam at the opposite side of the contact end, and the second beam may be shorter than the first beam.
[0018] Each contact end of the first actuator and the shuttle corresponding to the contact end may be coated with carbon nanotube (CNT).
[0019] In the second actuator, the plurality of heating lines may be integrally connected on both ends by a supporting end, a driving beam may be configured at the center part of each heating line, and the driving beam may contact the rear end of the shuttle by an extending change amount of each heating line to drive the shuttle.
[0020] The beam member may be formed with a curved surface of an oval shape.
[0021] The main substrate may be a silicon-on-insulator (SOI) substrate.
[0022] The driving unit may be made as a comb finger driver.
[0023] An exemplary embodiment of the present invention applies the voltage to the second actuator to move the shuttle contacting the contact end of the first actuator to the side of the spring connected to the mass body, thereby constraining the spring and controlling the rigidity thereof, and accordingly, through the method of tuning the resonance frequency, the tuning state may be maintained by the frictional force of the CNT coated on the contact end even if the supply of the voltage is removed, such that there is a very beneficial effect in terms of power consumption.
[0024] Further, effects that can be obtained or expected from exemplary embodiments of the present invention are directly or suggestively described in the following detailed description. That is, various effects expected from exemplary embodiments of the present invention will be described in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 is a cross-sectional view of a MEMS resonator according to an exemplary embodiment of the present invention.
[0026] FIG. 2 is an enlarged cross-sectional view of a tuning unit of a MEMS resonator according to an exemplary embodiment of the present invention.
[0027] FIG. 3 is an operation diagram explaining a tuning unit of a MEMS resonator according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0028] It is understood that the term “vehicle” or “vehicular” or other similar term as used herein is inclusive of motor vehicles in general such as passenger automobiles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g. fuels derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example both gasoline-powered and electric-powered vehicles.
[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Throughout the specification, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. In addition, the terms “unit”, “-er”, “-or”, and “module” described in the specification mean units for processing at least one function and operation, and can be implemented by hardware components or software components and combinations thereof.
[0030] Further, the control logic of the present invention may be embodied as non-transitory computer readable media on a computer readable medium containing executable program instructions executed by a processor, controller or the like. Examples of computer readable media include, but are not limited to, ROM, RAM, compact disc (CD)-ROMs, magnetic tapes, floppy disks, flash drives, smart cards and optical data storage devices. The computer readable medium can also be distributed in network coupled computer systems so that the computer readable media is stored and executed in a distributed fashion, e.g., by a telematics server or a Controller Area Network (CAN).
[0031] Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. However, drawings and a detailed description to be described later relate to an exemplary embodiment of several exemplary embodiments for effectively describing a characteristic of the present invention. Therefore, the present invention is not limited to only the following drawing and description.
[0032] FIG. 1 is a cross-sectional view of a MEMS resonator according to an exemplary embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of a tuning unit of a MEMS resonator according to an exemplary embodiment of the present invention.
[0033] Referring to FIG. 1 , the MEMS resonator 1 according to an exemplary embodiment of the present invention includes a main substrate 11 , a mass body 13 , a driving unit 15 , and a tuning part 17 .
[0034] First, the main substrate 11 forms a receiving part A at the center.
[0035] In this case, the main substrate 11 is made of an SOI (silicon-on-insulator) substrate.
[0036] The SOI substrate refers to a substrate in which a buried insulating layer is laminated between an underlying supporting substrate and the main substrate 11 in a sandwich structure. The SOI substrate is configured to form complete element separation.
[0037] Also, the mass body 13 is positioned at the center of the receiving part A on the main substrate 11 . The mass body 13 has one end part that is elastically supported through the first elastic member S 1 on the main substrate 11 , and a center part that is elastically supported through the second elastic member S 2 .
[0038] Also, the driving unit 15 is disposed at one side of the receiving part A on the main substrate 11 . The driving unit 15 includes two drivers facing each other, and is configured to have a translational movement with respect to one direction by applying an AC voltage to the two drivers. Accordingly, the mass body 13 is driven due to the translation of the driving unit 15 . The driving unit 15 is made of a comb finger driver.
[0039] The tuning part 17 includes four tuning units 20 in the receiving part A on the main substrate 11 . That is, in the tuning part 17 , the tuning units 20 are symmetrical as pairs with respect to the second elastic member S 2 , and are respectively configured corresponding to both sides of the center part of the mass body 13 .
[0040] The tuning part 17 intentionally restrains the second elastic member S 2 by the actuating operation of each tuning unit 20 to change the rigidity thereof, thereby controlling the frequency. Referring to FIG. 2 , the tuning unit 20 includes an auxiliary substrate 21 , a first actuator 23 , a second actuator 25 , and a beam member 27 .
[0041] The auxiliary substrate 21 is disposed corresponding to the center part of the mass body 13 inside the receiving part A of the main substrate 11 . Also, the first actuator 23 is disposed in the receiving part A between the main substrate 11 and the auxiliary substrate 21 . The first actuator 23 includes a shuttle 29 positioned at the center of the receiving part A between the main substrate 11 and the auxiliary substrate 21 .
[0042] In this case, the front end of the shuttle 29 is connected to the third elastic member S 3 disposed between the main substrate 11 and the auxiliary substrate 21 .
[0043] Also, the first actuator 23 is respectively disposed to correspond to the main substrate 11 and the auxiliary substrate 21 at both sides of the shuttle 29 and a contact end 24 that contacts the shuttle 29 at each inner end.
[0044] Here, the contact end 24 of the first actuator 23 and the shuttle 29 corresponding to the contact end 24 are coated with CNT (carbon nanotubes).
[0045] The CNT uses a chemical vapor deposition (CVD) method by iron (Fe) as a catalyst, and is synthesized by injecting ammonia (NH3) gas and acetylene (C2H2) gas at about 700° C. The CNT may be grown to approximately 10 μm.
[0046] The first actuator 23 has a deformation part made of a first beam B 1 and a second beam B 1 connected to the electrode from the contact end. The first beam B 1 is disposed at both sides corresponding to the shuttle 29 , and the second beam B 2 is formed with the same thickness at the outside of the first beam B 1 at the opposite side of the contact end 24 . In this case, the second beam B 2 has a shorter length than the first beam B 1 .
[0047] The first actuator 23 drives each contact end 24 positioned at both sides with respect to the shuttle 29 positioned at the center depending on the input application voltage, thereby controlling the movement of the shuttle 29 .
[0048] The second actuator 25 is located at the rear part of the first actuator 23 at the opposite side of the second elastic member S 2 . The second actuator 25 is configured with a plurality of heating lines 30 extending by the application to act on the rear end of the shuttle 29 .
[0049] In this case, the plurality of heating lines 30 are integrally connected by a supporting end 31 through both ends and a driving beam 33 is configured at the center.
[0050] As the driving beam 33 contacts the rear end of the shuttle 29 by the extending change amount of each heating line 30 , the second actuator 25 drives the shuttle 29 .
[0051] The above-described second actuator 25 may be a chevron thermal actuator.
[0052] Also, the beam member 27 is positioned to enable it to contact the second elastic member S 2 inside the receiving part A between the main substrate 11 and the auxiliary substrate 21 . The beam member 27 is formed into a curved surface of an oval shape to be fixed to the front end of the shuttle 29 . For example, the beam member 27 may be made of a bow-shaped beam.
[0053] FIG. 3 is an operation diagram explaining a tuning unit of a MEMS resonator according to an exemplary embodiment of the present invention.
[0054] FIG. 3 (A) shows an initial state of the tuning unit 20 , and the shuttle 29 positioned at the center of the first actuator 23 is in contact with the contact end 24 and is connected to the beam member 27 of the front end. In this case, the beam member 27 maintains separation from the second elastic member S 2 .
[0055] Referring to FIG. 3 (B), the voltage is applied to the second actuator 25 of the tuning unit 20 . In this case, the plurality of heating lines 30 formed in the second actuator 25 extend to be deformed such that the driving beam 33 positioned at the center of the heating line 30 contacts the rear end of the shuttle 29 positioned at the center of the first actuator 23 , and the shuttle 29 is moved to the side of the second elastic member S 2 .
[0056] That is, while the beam member 27 with the oval shape fixed to the front end of the shuttle 29 contacts the second elastic member S 2 and shrinks, as the length of the second elastic member S 2 is changed and the rigidity is changed, the movement of the mass body 13 connected to the second elastic member S 2 is controlled such that the frequency is tuned.
[0057] Referring to FIG. 3(C) , in the state that the beam member 27 is in contact with the second elastic member S 2 , even if the voltage applied to the second actuator 25 is removed, the shuttle 29 maintains its position by the frictional force with each contact end 24 of the first actuator 23 positioned at both sides of the shuttle 29 . The position of the shuttle 29 is maintained by the frictional force of the CNT coated between the shuttle 29 and the contact end 24 contacting thereto.
[0058] Referring to FIG. 3(D) , in order to return the shuttle 29 to the original position after tuning the frequency, the voltage is applied to the first actuator 23 . Thus, while the first actuators 23 are separated to both sides of the shuttle 29 by the deformation length difference of the first beam B 1 and the second beam B 2 of each deformation part, the contact end 24 formed at the front end of each deformation part is separated from the shuttle 29 and the mutual frictional force by the CNT is removed, and resultantly, the shuttle 29 is returned to the original position by using the elastic force of the second elastic member S 2 .
[0059] In this case, the deformation part is formed of the structure in which the second beam B 2 having the shorter length than the first beam B 1 is disposed outside the first beam B 1 , and accordingly, the deformation is induced in the shape such that the first actuators 23 are inclined outside by the first beam B 1 having the relatively longer length.
[0060] Accordingly, while the shuttle 29 that has restricted the second elastic member S 2 is restored to the original position, the tuning part 17 is returned to the initial state.
[0061] While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
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A MEMS resonator includes a main substrate forming a receiving part at a center of the main substrate; a mass body having one end part and a center part elastically supported by both sides of the main substrate; a driving unit configured at one side of the receiving part on the main substrate and producing a driving torque by a voltage applied to both sides of the one end part of the mass body to move a position of the mass body with respect to the main substrate; and a tuning part including a pair of tuning units provided symmetrically with respect to the second elastic member, and having a beam member changing a length of the second elastic member by an actuating operation of each tuning unit to control a frequency.
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CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority of U.S. Provisional Application No. 61/521,151, filed on Aug. 8, 2011, the entirety of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a wireless device, and more particularly to a method for controlling transmission power of a wireless device.
2. Description of the Related Art
In recent years, mobile phones have become more popular and have various powerful applications, such as “Hot Spot” wireless fidelity (WiFi) wireless Internet connection, which provides Internet access over a wireless local area network (WLAN) for users nearby a mobile phone. However, the mobile phone functioning as a Hot Spot will consume lots of power due to the mobile phone operating in a transmission mode.
Therefore, it is desired to save power for mobile devices in a transmission mode.
BRIEF SUMMARY OF THE INVENTION
Methods for controlling transmission power of a wireless device and a wireless device are provided. An embodiment of a method for controlling transmission power of a wireless device is provided. The method comprises: establishing a WiFi link to a communication device; monitoring a data rate of data packets transmitted to the communication device; obtaining first information from the communication device in response to the transmitted data packets; decreasing a transmission power of the wireless device when the data rate of the data packets reaches a highest data rate and the first information satisfies a specific condition.
Furthermore, an embodiment of a method for controlling transmission power of a wireless device is provided. The method comprises: establishing a WiFi link to a communication device; transmitting data packets to the communication device according to a first transmission power; adjusting a data rate of the data packets according to a packet error rate (PER); transmitting data packets to the communication device according to a second transmission power smaller than the first transmission power when the data rate of the data packets reaches a highest data rate and the PER satisfies a specific condition; and transmitting data packets to the communication device according to the first transmission power when the data rate of the data packets reaches the highest data rate and the PER does not satisfy the specific condition.
Moreover, a wireless device is provided. The wireless device comprises a processor, an antenna and a radio frequency (RF) module coupled between the antenna and the processor. The RF module comprises a power amplifier which transmits data packets from the processor to a communication device with a first transmission power. The processor establishes a WiFi link to the communication device via the RF module and the antenna, and obtains first information from the communication device in response to the transmitted data packets. The processor controls the power amplifier to transmit the data packets with a second transmission power smaller than the first transmission power when a data rate of the data packets reaches a highest data rate and the first information satisfies a specific condition.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
FIG. 1 shows a schematic diagram illustrating IEEE 802.11 wireless fidelity (WiFi) network communications between two electrical devices;
FIG. 2 shows a block diagram illustrating a WLAN module equipped in a wireless device according to an embodiment of the invention;
FIG. 3 shows a method for controlling transmission power of a wireless device with the WLAN module of FIG. 2 according to an embodiment of the invention;
FIG. 4 shows a method for controlling transmission power of a wireless device with the WLAN module of FIG. 2 according to another embodiment of the invention;
FIG. 5 shows an exemplary diagram illustrating the relationships between a data rate and input power (RSSI).
FIG. 6 shows a method for controlling transmission power of a wireless device with the WLAN module of FIG. 2 according to another embodiment of the invention;
FIGS. 7A and 7B show a method for controlling transmission power of a wireless device with the WLAN module of FIG. 2 according to another embodiment of the invention;
FIG. 8 shows a schematic diagram illustrating a mobile network communication system according to an embodiment of the invention; and
FIG. 9 shows a schematic diagram illustrating an internet network communication system according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
FIG. 1 shows a schematic diagram illustrating IEEE 802.11 wireless fidelity (WiFi) network communications between two electrical devices 10 and 20 , wherein the electrical devices 10 and 20 may be computers, portable devices (such as mobile phone, tablet computer) and so on. In FIG. 1 , the devices 10 and 20 are equipped with wireless local area network (WLAN) modules (e.g. 802.11b, 802.11g or 802.11n) to perform peer to peer communications. When one of the electrical devices 10 and 20 uses a highest data rate to transmit data packets to the other electrical device, e.g. 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification, the one of the electrical devices 10 and 20 will perform a method to control transmission power of the WLAN module thereof according to an embodiment of the invention, so as to achieve lower power consumption.
FIG. 2 shows a block diagram illustrating a WLAN module 100 equipped in a wireless device (e.g. 10 or 20 of FIG. 1 ) according to an embodiment of the invention. The WLAN module 100 comprises a Baseband chip 110 and a radio frequency (RF) module 120 . The RF module 120 is coupled between the Baseband chip 110 and an antenna 170 , which comprises a low noise amplifier (LNA) 130 , a power amplifier (PA) 140 and a TX/RX processing unit 150 . The TX/RX processing unit 150 receives and modulates the data DAT out from a processor 160 of the Baseband chip 110 , so as to provide the RF signal RF out to the antenna 170 via the PA 140 for transmitting data packets to another wireless device. Simultaneously, the processor 160 of the Baseband chip 110 further provides a control signal Ctrl to the PA 140 for controlling transmission power of the wireless device. In general, the receiving wireless device will send back acknowledge (ACK) messages in response to the data packets transmitted by the transmitting wireless device. Therefore, the TX/RX processing unit 150 of the transmitting wireless device will receive and demodulate the RF signal RF in corresponding to the ACK message via the LNA 130 and the antenna 170 , so as to provide the data DAT in to the processor 160 of the Baseband chip 110 , and then the processor 160 of the Baseband chip 110 obtains a packet error rate (PER) according to the data DAT in . The PER is the number of incorrectly received data packets divided by the total number of received packets, wherein a packet is declared incorrect if at least one bit is erroneous. Therefore, the smaller the PER, the better the communication quality. When the receiving wireless device and the transmitting wireless device approach each other, the processor 160 of the Baseband chip 110 will obtain a better PER.
FIG. 3 shows a method for controlling transmission power of a wireless device with the WLAN module 100 of FIG. 2 according to an embodiment of the invention. Referring to FIG. 2 and FIG. 3 together, first, the WLAN module 100 of the wireless device operates in a normal mode and establishes a WiFi link to a communication device (step S 210 ). In step S 220 , the WLAN module 100 continues to monitor/detect a data rate of data packets transmitted to the communication device and obtains a PER corresponding to the ACK messages from the communication device in response to the transmitted data packets. In the WLAN module 100 , the processor 160 obtains the data rate of data packets transmitted to the communication device according to the modulation operations of the TX/RX processing unit 150 . Once it is detected that the PER is good (i.e. the PER does not exceed a threshold PER th ) and the data rate reaches a highest data rate that can be supported by the WLAN module 100 (step S 230 ), such as 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification, the WLAN module 100 enters a power conservation mode (step S 240 ), and then the processor 160 provides the control signal Ctrl to the PA 140 , to decrease transmission power. Next, the WLAN module 100 checks whether the PER is still good (i.e. the PER does not exceed the threshold PER th ) (step S 250 ). If no (i.e. the PER exceeds the threshold PER th ), the WLAN module 100 returns back to the normal mode, and the processor 160 provides the control signal Ctrl to the PA 140 , to recover the transmission power (i.e. increase transmission power) (step S 270 ), and then step S 220 is performed to continue monitoring the data rate and the PER. On the contrary, if the PER is good (i.e. the PER does not exceed the threshold PER th ), the WLAN module 100 continues to operate in the power conservation mode, so as to transmit the data packets with lower transmission power to the communication device (step S 260 ). Thus, power consumption of the WLAN module 100 is decreased. In addition, the WLAN module 100 periodically checks the PER in the power conservation mode (step S 250 ), so as to determine whether to return to the normal mode. In the power conservation mode, the wireless device of the invention may decrease the current transmission power according a predefined scale, such as 1 dB, 3 dB (i.e. a half of the current transmission power) and so on, so as to obtain an optimal transmission power without affecting the PER. Furthermore, the wireless device performs the method of FIG. 3 without additional circuits and complex operations due to the data rate and the PER being given. In other words, it is easy to implement the method for controlling transmission power of a wireless device according to the embodiment. In the embodiment, the threshold PER th is determined according to actual applications.
TABLE 1 shows an example illustrating the relationships between the data rate, transmission power and power consumption of various WiFi modes according to the method of FIG. 3 . Taking the 802.11b specification as an example, when a wireless device uses a highest data rate 11 Mbps to transmit data packets to a communication device in a normal mode and obtains a good PER in response to the transmitted data packets, the wireless device will enter a power conservation mode, to decrease the transmission power from 18 dBm to 13 dBm. Thus, power consumption of the wireless device is decreased from 260 mA to 170 mA.
TABLE 1
Transmission Power
power consumption
Mode
Data rate
(dBm)
(mA)
802.11b
1 Mbps
18
260
(Normal mode)
2 Mbps
18
260
(Normal mode)
5.5 Mbps
18
260
(Normal mode)
11 Mbps
18
260
(Normal mode)
11 Mbps
13
170
(power conservation
mode)
802.11g
6 Mbps
13
170
(Normal mode)
9 Mbps
13
170
(Normal mode)
12 Mbps
13
170
(Normal mode)
18 Mbps
13
170
(Normal mode)
24 Mbps
13
170
(Normal mode)
36 Mbps
13
160
(Normal mode)
48 Mbps
13
140
(Normal mode)
54 Mbps
13
140
(Normal mode)
54 Mbps
10
100
(power conservation
mode)
802.11n
MCS0
13
170
(Normal mode)
MCS1
13
170
(Normal mode)
MCS2
13
170
(Normal mode)
MCS4
13
170
(Normal mode)
MCS5
13
160
(Normal mode)
MCS6
13
140
(Normal mode)
MCS7
13
140
(Normal mode)
MCS7
10
100
(power conservation
mode)
Referring back to FIG. 2 , the RF module 120 may further use a measure circuit to obtain a received signal strength indicator (RSSI) according to the RF signal RF in that comprises the ACK messages from the communication device in response to the data packets transmitted by the wireless device, and provide the RSSI to the processor 160 of the Baseband chip 110 . The measure circuit may be an independent circuit or may be integrated into the LNA 130 or the TX/RX processing unit 150 . FIG. 4 shows a method for controlling transmission power of a wireless device with the WLAN module 100 of FIG. 2 according to another embodiment of the invention. Referring to FIG. 2 and FIG. 4 together, first, the WLAN module 100 of the wireless device operates in a normal mode and establishes a WiFi link to a communication device (step S 310 ). In step S 320 , the WLAN module 100 continues to monitor/detect a data rate of data packets transmitted to the communication device and obtains an RSSI corresponding to the ACK messages from the communication device in response to the transmitted data packets. Once it is detected that the RSSI is good (i.e. the RSSI exceeds a threshold RSSI th ) and the data rate reaches a highest data rate that can be supported by the WLAN module 100 (step S 330 ), such as 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification, the WLAN module 100 enters a power conservation mode (step S 340 ), and then the processor 160 provides the control signal Ctrl to the PA 140 , to decrease transmission power. Next, the WLAN module 100 checks whether the PER is good (step S 350 ). If no (i.e. the PER exceeds the threshold PER th ), the WLAN module 100 returns back to the normal mode, and the processor 160 provides the control signal Ctrl to the PA 140 , to recover the transmission power (i.e. increase transmission power) (step S 370 ), and then step S 320 is performed to continue monitoring the data rate and the RSSI. On the contrary, if the PER is good (i.e. the PER does not exceed the threshold PER th , the WLAN module continues to operate in the power conservation mode, so as to transmit the data packets with lower transmission power to the communication device (step S 360 ). Thus, power consumption of the WLAN module 100 is decreased. In addition, the WLAN module 100 periodically checks the PER in the power conservation mode (step S 350 ), so as to determine whether to return to the normal mode. In the embodiment, the threshold PER th and RSSI th are determined according to actual applications.
FIG. 5 shows an exemplary diagram illustrating the relationships between a data rate and input power (RSSI). In FIG. 5 , the wireless device will switch to a power conservation mode from a normal mode when the data rate reaches a highest value such as 54 Mbps and the input power is sustained at a good quality such as a value larger than −60 dBm, thus the transmission power drops to 10 dBm from 13 dBm.
FIG. 6 shows a method for controlling transmission power of a wireless device with the WLAN module 100 of FIG. 2 according to another embodiment of the invention. Referring to FIG. 2 and FIG. 6 together, first, the WLAN module 100 of the wireless device operates in a normal mode and establishes a WiFi link to a communication device (step S 602 ). In step S 604 , the WLAN module 100 continues to monitor a data rate of data packets transmitted to the communication device and obtains a PER in response to the transmitted data packets. Next, it is determined whether the PER is good (step S 606 ). If no (i.e. the PER exceeds the threshold PER th ), the WLAN module 100 decreases the data rate of data packets (step S 610 ). Otherwise, if the PER has not exceeded the threshold PER th ), the WLAN module 100 continues to monitor the data rate (step S 608 ), to detect whether the data rate has reached a highest data rate that can be supported by the WLAN module 100 (step S 612 ), such as 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification. If the data rate has not reached the highest data rate, the WLAN module 100 increases the data rate of data packets (step S 614 ), and then step S 606 is performed to continue monitoring the PER. Otherwise, the WLAN module 100 enters a power conservation mode (step S 616 ), and then the processor 160 provides the control signal Ctrl to the PA 140 , to decrease transmission power. Next, the WLAN module 100 checks whether the PER is still good (step S 618 ). If no (i.e. the PER exceeds the threshold PER th ), the WLAN module 100 returns back to the normal mode, and the processor 160 provides the control signal Ctrl to the PA 140 , to recover the transmission power (i.e. increase transmission power) (step S 620 ), and then step S 604 is performed to continue monitoring the data rate. On the contrary, if the PER is good (i.e. the PER does not exceed the threshold PER th ), the WLAN module 100 continues to operate in the power conservation mode, so as to transmit the data packets with the decreased transmission power (step S 622 ). Thus, power consumption of the WLAN module 100 is decreased. In addition, the WLAN module 100 periodically checks the PER in the power conservation mode (step S 618 ), so as to determine whether to return to the normal mode. In the embodiment, the threshold PER th is determined according to actual applications.
FIGS. 7A and 7B show a method for controlling transmission power of a wireless device with the WLAN module 100 of FIG. 2 according to another embodiment of the invention. Referring to FIG. 2 and FIGS. 7A and 7B together, first, the WLAN module 100 of the wireless device operates in a normal mode and establishes a WiFi link to a communication device (step S 702 ). In step S 704 , the WLAN module 100 continues to monitor a data rate of data packets transmitted to the communication device and obtains a PER in response to the transmitted data packets. Next, it is determined whether the PER is good (step S 706 ). If no (i.e. the PER exceeds a threshold PER th ), the WLAN module 100 decreases the data rate of data packets (step S 710 ). Otherwise, if the PER has not exceeded the threshold PER th , the WLAN module 100 continues to monitor the data rate (step S 708 ), to detect whether the data rate has reached a highest data rate that can be supported by the WLAN module 100 (step S 712 ), such as 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification. If the data rate has not reached the highest data rate, the WLAN module 100 increases the data rate of data packets (step S 714 ), and then step S 706 is performed to continue monitoring the PER. Otherwise, the WLAN module 100 further monitors an RSSI (step S 716 ). Next, it is determined whether the RSSI exceeds a predetermined threshold RSSI th (step S 718 ). If the RSSI has not exceeded the predetermined threshold RSSI th , step S 704 is performed to continue monitoring the data rate. Otherwise, the WLAN module 100 enters a power conservation mode (step S 720 ), and then the processor 160 provides the control signal Ctrl to the PA 140 , to decrease transmission power. Next, the WLAN module 100 checks whether the PER is good (step S 722 ). If no (i.e. the PER exceeds the threshold PER th ), the WLAN module 100 returns back to the normal mode and the processor 160 provides the control signal Ctrl to the PA 140 to recover the transmission power (step S 724 ), and then step S 704 is performed to continue monitoring the data rate. On the contrary, if the PER is good (i.e. the PER does not exceed the threshold PER th ), the WLAN module 100 continues to operate in the power conservation mode to transmit the data packets with the decreased transmission power (step S 726 ), thus power consumption of the WLAN module 100 is decreased. In addition, the WLAN module 100 periodically checks the PER in the power conservation mode (step S 722 ), so as to determine whether to switch back to the normal mode. In the embodiment, the threshold PER th and RSSI th are determined according to actual applications.
FIG. 8 shows a schematic diagram illustrating a mobile network communication system according to an embodiment of the invention. In FIG. 8 , all electrical devices 10 , 20 , 30 , 40 and 50 are equipped with WLAN modules (e.g. 802.11b, 802.11g or 802.11n specifications) to perform data communications, wherein the device 10 camps on a cellular station 60 of a service network. The wireless communications between the device 10 and the service network may be in compliance with various wireless technologies, such as the Global System for Mobile communications (GSM) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for Global Evolution (EDGE) technology, Wideband Code Division Multiple Access (WCDMA) technology, Code Division Multiple Access 2000 (CDMA 2000) technology, Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology, Worldwide Interoperability for Microwave Access (WiMAX) technology, Long Term Evolution (LTE) technology, LTE Advanced (LTE-A) technology, and others. In FIG. 8 , the device 10 functions as a hotspot in WiFi technology, which offers Internet access for the devices 20 , 30 , 40 and 50 , thus the devices 20 , 30 , 40 and 50 can access an Internet network through the device 10 and the cellular station 60 of the service network. In FIG. 8 , the device 10 may use different or the same data rates to transmit packets to the devices 20 , 30 , 40 and 50 . Therefore, when the device 10 transmits packets to at least one of the devices 20 , 30 , 40 and 50 with a highest data rate (e.g. 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification) and obtains a good PER (or RSSI) corresponding to the highest data rate, the device 10 may determine whether to decrease transmission power according the data rates of the devices other than the one with the highest data rate and the corresponding PERs or RSSIs. Specifically, according to the data rates of the packets transmitted to various devices 20 , 30 , 40 and 50 and the corresponding PERs or RSSIs, the device 10 will appropriately control its transmission power according to the methods of the invention without affecting packet transmissions, so as to decrease power consumption of the wireless device 10 .
FIG. 9 shows a schematic diagram illustrating an internet network communication system according to an embodiment of the invention. In FIG. 9 , the electrical device 80 transmits data packets to an Internet network 90 through a wireless access point (AP) device 70 . As described above, when the electrical device 80 transmits data packets with a highest data rate (e.g. 11 Mbps for the 802.11b specification, 54 Mbps for the 802.11g specification or MCS7 for the 802.11n specification), the electrical device 80 may further determine whether to enter a power conservation mode according to the corresponding PER or RSSI. Specifically, if the electrical device 80 obtains a good PER (or RSSI) corresponding to the highest data rate, the wireless device 80 will appropriately control its transmission power without affecting packet transmissions, so as to decrease power consumption.
The embodiments of the innovation disclose the methods to control transmission power (i.e. output power) of a wireless device which uses IEEE 802.11 WiFi communication technologies to transmit data packets to other wireless devices. When the wireless device uses a highest data rate to transmit the data packets to the other wireless devices, the wireless device will enter a power conservation mode to decrease its transmission power without degrading communication quality. Therefore, power consumption is decreased for the wireless device; especially, for short-distances in a peer to peer mode or access mode.
While the invention has been described by way of example and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
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A method for controlling transmission power of a wireless device is provided. A WiFi link is established to a communication device. A data rate of data packets transmitted to the communication device is monitored. Information from the communication device is obtained in response to the transmitted data packets. A transmission power of the wireless device is decreased when the data rate of the data packets reaches a highest data rate and the first information satisfies a specific condition.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to foreign French patent application No. FR 10 58684, filed on Oct. 22, 2010, the disclosure of which is incorporated by reference in its entirety.
FIELD OF THE DISCLOSED SUBJECT MATTER
[0002] The present invention relates to a matrix display device for displaying two merged images. It applies more particularly to the simultaneous display of two images whose definitions may differ.
BACKGROUND
[0003] Some applications involving the display of images involve a need for a merging of images, that is to say a simultaneous display of two images originating from two different sources. The two sources may notably originate from two image sensors of different natures, aiming to restore information of different natures on one and the same scene. For example, it may prove necessary to enable the display of a first image, for example in grey levels and in high definition, produced by a first high definition sensor, simultaneously with a second image, of lesser definition, and typically monochrome or two-color, for example produced by a second sensor. These two images may, for example, correspond respectively to a first image restored by a night vision sensor and a second image restored by an infrared sensor; or even to a first image restored by X-ray radiography, and a second image produced by magnetic resonance imaging. In the abovementioned two cases, the images represent one and the same scene. Also, the first image may represent a scene restored by a high definition sensor, and the second image may represent symbols, text or even menus that have to be displayed simultaneously with the first image.
[0004] The present invention relates to the abovementioned applications, as nonlimiting examples, and may also be applied to other examples. More particularly, the present invention relates to the merging of images for a display via a matrix display device. A matrix display device is essentially formed by a matrix of pixels, associated with an addressing system; active matrix and passive matrix systems are known from the prior art. The pixels may, for example, be formed by liquid crystals, commonly designated by the acronym LCD, standing for “Liquid Crystal Display”, or even by light-emitting diodes, or LEDs, or even by organic light-emitting diodes, commonly designated by the acronym OLED. The matrix of pixels is usually associated with a controller, formatting the video signal and generating the control signals intended for the matrix. Hereinafter, it can be assumed, in the interests of simplicity, that a control signal is limited to a light intensity signal, that can be likened to a quantified and standardized value, that may, for example, be a voltage value to be applied to a light-emitting element, or a numeric value, for example coded on 8 bits and thus between 0 and 255, intended for a matrix or for a numeric pixel. It may, for example, be understood that the signals applied are luminance signals, for which the magnitudes vary from a zero value corresponding to a black level, to a maximum value. The formation of an image on a display device, by the application of appropriate signals to the pixels, can be referred to by the term “mapping”. The controller may, for example, be implemented in an integrated electronic circuit of ASIC type, the acronym standing for “Application Specific Integrated Circuit”. The controller may also, for example, be implemented via a programmable microcontroller. The controller may also, for example, be implemented via a programmable component of FPGA type, the acronym standing for “Field-Programmable Gate Array”, of EPLD type, the acronym standing for “Erasable Programmable Logic Device”, or other known types of programmable components.
[0005] The devices known from the prior art that make it possible to display merged images as in the examples described above, usually proceed with a display on a polychrome screen, typically of the type commonly designated by the acronym RGB, the acronym referring to the three colors Red, Green, Blue, forming, by combination, all the visible colors, of a merged image generated by a computer, implemented in a dedicated logic circuit, or else via software run on a powerful computer. The merging algorithms may be relatively complex, and the definition of the merged image is significantly degraded, the latter being displayed on a polychrome screen, and being essentially composed of the first monochrome image. In practice, the polychrome display matrices are usually made up of a plurality of groups of pixels or “sub-pixels”, a sub-pixel being dedicated to the display of a basic color, for example by being associated with a color filter, or else by being formed by a luminescent element suitable for producing different colored light signals. Typically, a group may consist of three sub-pixels: each of the pixels being associated with a filter of a basic color, the group then making it possible to display the desired color from a palette of colors, by combination of the sub-pixel control signals. It is, for example, usual practice to employ arrangements of sub-pixels respectively associated with red, green and blue color filters.
SUMMARY
[0006] One aim of the present invention is to overcome at least the abovementioned drawbacks, by proposing a matrix display device for displaying two merged images, that best preserves the definition of the image that has the higher definition.
[0007] One advantage of the invention is that it makes it possible to implement algorithms, the implementation of which is facilitated, and can, for example, be carried out by the controller of the matrix display.
[0008] To this end, the subject of the invention is a matrix display device with a definition determined by a plurality of pixels, the matrix display device comprising:
at least one controller suitable for producing display light intensity signals for each of the pixels, and a matrix of pixels organized in a mosaic of a plurality of identical arrangements of a predetermined number of pixels, wherein a first plurality of pixels of one of the arrangements are dedicated to display of a first image and receive the light intensity signals associated with the pixels of the first image (I 1 ) that correspond thereto, one or more other pixels of the arrangement are dedicated to the display of a second image (I 2 ) and receiving light intensity signals associated with the pixels of said second image (I 2 ) that correspond thereto, the matrix display device producing the merged display of the first image (I 1 ) and of the second image (I 2 ), the two images (I 1 , I 2 ) being, if necessary, redimensioned by scaling means.
[0011] In one embodiment of the invention, each of said arrangements can be formed by a square of four pixels: three pixels of each arrangement being associated with the light intensity signals intended for the corresponding pixels of the first image, and the remaining pixel being associated with the light intensity signal intended for the corresponding pixel of the second image.
[0012] In one embodiment of the invention, each of said arrangements can be formed by a square of four pixels: two pixels of each arrangement being associated with the light intensity signals intended for the corresponding pixels of the first image, and the remaining two pixels being associated with the light intensity signals intended for the corresponding pixels of the second image.
[0013] In one embodiment of the invention, the pixels dedicated to the display of the first image can emit a first single color, the pixels dedicated to the display of the second image being able to emit a second single color different from the first color.
[0014] In one embodiment of the invention, said remaining pixels of the display device can be configured to display two colors which, by combination, make it possible to restore the color associated with the first pixel.
[0015] In one embodiment of the invention, the controller can be configured to apply to said three pixels of the arrangements for which said remaining pixels have a quantified light intensity signal value greater than a predetermined threshold value, an attenuation function attenuating the quantified values of the signals to be applied.
[0016] In one embodiment of the invention, the attenuation function can attenuate the quantified values of the light intensity signals to be applied respectively to said three pixels Si, according to the following relationship:
[0000] Si=b ·exp(− a·S 1 i )· S 1 i
[0000] for i=1; 3; 4, a and b being real parameters, S 1 i being the quantified values of the light intensity signals of the corresponding pixels of the first image.
[0017] In one embodiment of the invention, the controller can be configured to apply, to said two pixels of the arrangements for which said remaining pixels have a quantified light intensity signal value greater than a predetermined threshold value, an attenuation function attenuating the quantified values of the signals to be applied.
[0018] In one embodiment of the invention that is dependent on the preceding embodiment, the attenuation function can attenuate the quantified values of the light intensity signals to be applied respectively to said two pixels, according to the following relationship:
[0000] Si=b ·exp(− a·S 1 i )· S 1 i
[0000] for i=1; 4, a and b being real parameters.
[0019] In one embodiment of the invention, said remaining pixels of the display device are configured to display two colors which, by combination, make it possible to restore the color associated with the first image.
[0020] In one embodiment of the invention, the controller can be configured to apply, to said remaining two pixels of each of the arrangements of the display device for which the pixels of the arrangements of said second image that correspond thereto have a quantified light intensity signal value less than a determined threshold, values derived from a combination of the quantified values of the light intensity signals of the first image, according to the following relationships:
[0000] S 2=a*( S 12+ S 13)/2,
[0000] S 3=b*( S 12+ S 13)/2;
[0000] a and b being real parameters, the sum of which equals 2.
[0021] In one embodiment of the invention, the matrix display device can include a first controller interfacing with said first number of pixels of each arrangement and corresponding to the first image, and a second controller interfacing with the other pixels of each arrangement and corresponding to said second image.
[0022] According to various embodiments of the invention, the matrix display device can be configured to display a first image, essentially monochrome, produced by a night vision sensor or by an infrared sensor or by an X-ray imaging sensor, merged with the display of a second image, essentially monochrome, produced by an infrared sensor, by an echography sensor, or a monochrome or two-color symbology image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Other features and advantages of the invention will become apparent from reading the description, given by way of example, in light of the appended drawings which represent:
[0024] FIG. 1 , a diagram giving a synoptic presentation of the general principle of a matrix display device, in an exemplary embodiment of the invention;
[0025] FIG. 2 , a diagram giving a synoptic presentation of the display produced by an arrangement of pixels, in a first exemplary embodiment of the invention;
[0026] FIG. 3 , a diagram giving a synoptic presentation of the display produced on an arrangement of pixels, in a second exemplary embodiment of the invention;
[0027] FIG. 4 , a diagram presenting an exemplary embodiment of a matrix display device according to one embodiment of the invention.
DETAILED DESCRIPTION
[0028] FIG. 1 is a diagram presenting a synoptic illustration of the general principle of a matrix display device according to an exemplary embodiment of the present invention.
[0029] A first image I 1 is partially illustrated in FIG. 1 , the first image I 1 having first, if necessary, been redimensioned so as to offer a definition identical to the definition of the matrix of pixels of a display device 100 . In the example illustrated in FIG. 1 , the matrix of pixels of the display device 100 is rectangular, with n columns and p rows of pixels. The present invention can also be applied to matrices of different forms. The display device 100 may, for example, be a display of OLED, or LED, or LCD type, or of any other known type, associated with a controller which is not represented in FIG. 1 .
[0030] Similarly, a second image I 2 is partially illustrated in FIG. 1 , this also having, if necessary, been redimensioned so as to offer a definition identical to that of the matrix of pixels of the display device 100 , or else to a definition corresponding to a subdefinition of that of the matrix of pixels of the display device 100 , for example, a quarter thereof.
[0031] The redimensioning, sometimes referred to by the term “upscaling” if the native definition of the image is lower than the definition of the display, or else by the term “downscaling” in the opposite case, can, for example, be implemented by a microcontroller which is not represented in FIG. 1 , according to methods which are intrinsically known from the prior art and not explained in the present description.
[0032] According to a specific feature of the present invention, a mosaic may be considered, this mosaic covering all the pixels of the two images I 1 , I 2 and the matrix of the display device 100 , and being formed by a plurality of identical arrangements of pixels. In the example illustrated in FIG. 1 and the subsequent figures, a square arrangement of four pixels P 1 , P 2 , P 3 , P 4 is considered. The present invention can, obviously, be applied with arrangements of a plurality of pixels, the number of which may differ from four, the form of the arrangements not necessarily being square or rectangular, provided that the arrangements as a whole can cover all the pixels considered.
[0033] The merged image resulting from the two images I 1 , I 2 can be formed via appropriate light intensity signals. Thus, the light intensity signals that make it possible to form the pixels P 1 , P 2 , P 3 , P 4 of an arrangement of pixels of the merged image can be respectively denoted S 1 , S 2 , S 3 , S 4 . The light intensity signals that make it possible to form the corresponding four pixels of the arrangement of the first image I 1 alone can be denoted S 11 , S 12 , S 13 , S 14 , and, similarly, the light intensity signals that make it possible to form the four pixels of the arrangement of the second image I 2 that correspond thereto can be denoted S 21 , S 22 , S 23 , S 24 .
[0034] The present invention proposes that each pixel P 1 , P 2 , P 3 , P 4 of an arrangement of pixels of the merged image be formed either via a light intensity signal S 11 , S 12 , S 13 , S 14 that makes it possible to form the first image I 1 , or via a light intensity signal S 21 , S 22 , S 23 , S 24 that makes it possible to form the second image I 2 , or via a light intensity signal resulting from a combination of the abovementioned signals S 11 , S 12 , S 13 , S 14 and S 21 , S 22 , S 23 , S 24 that makes it possible to respectively form the first image I 1 and the second image I 2 . Thus, a first number of pixels of an arrangement may receive light intensity signals associated with the pixels of the first image I 1 that correspond thereto, and the other pixels of the arrangement may receive the light intensity signals associated with the pixels of the second image I 2 that correspond thereto, or light intensity signals determined by a combination of the light intensity signals associated with the pixels of the two images I 1 , I 2 . Different examples of arrangements of pixels are described hereinbelow, notably with reference to FIGS. 2 and 3 ; it should be noted that these examples are in no way limiting on the present invention, and that other arrangements of pixels can be envisaged.
[0035] FIG. 2 is a diagram presenting a synoptic illustration of the display of two merged images produced on an exemplary arrangement of pixels, according to a first possible embodiment of the invention.
[0036] FIG. 2 presents an arrangement of four pixels P 1 , P 2 , P 3 , P 4 . For each arrangement of pixels, it is, for example, possible to reserve for a first pixel, for example for the first pixel P 1 of the matrix of the display device, the light intensity signal S 11 that makes it possible to display the first pixel P 1 of the first image. It is possible to also reserve for two other pixels, for example for the third and fourth pixels P 3 , P 4 of the matrix of the display device, the light intensity signals S 13 and S 14 that respectively make it possible to display the third and fourth pixels of the first image. Finally, it is possible to reserve for the last pixel of the arrangement, that is to say, for example, for the second pixel P 2 of the matrix of the display device, the light intensity signal S 22 that makes it possible to display the second pixel P 2 of the second image. Such an exemplary arrangement is particularly suited to the cases where the second image is monochrome. In this exemplary embodiment, the second pixel P 2 , for each arrangement of the matrix of the display device, can be associated with a colored filter.
[0037] Practically, the display of the duly merged image can, for example, be implemented via the following operations, performed by means of the controller of the display device:
a first operation of mapping the first image to the display device, the controller then applying the light intensity signals S 11 , S 13 and S 14 respectively to the first, third and fourth pixels P 1 , P 3 , P 4 of all the arrangements of pixels forming the display device; a second operation of mapping the second image to the display device, the controller then applying the light intensity signal S 22 to the second pixels P 2 of all the arrangements of pixels forming the display device. It can be seen here that the mapping of the second image I 2 to the display device is produced on a definition corresponding to the number of pixels intended for the display of the second image I 2 ; that is to say, in the case of the example described here, the pixels P 2 being assigned to the display of the image I 2 , on a quarter of the definition of the matrix of the display device.
[0040] FIG. 3 is a diagram presenting a synoptic illustration of the display of two merged images produced on an exemplary arrangement of pixels, according to a second possible embodiment of the invention.
[0041] FIG. 3 presents an arrangement of four pixels P 1 , P 2 , P 3 , P 4 . For each arrangement of pixels, it is, for example, possible to reserve for a first pixel, for example for the first pixel P 1 of the matrix of the display device, the light intensity signal S 11 that makes it possible to display the first pixel P 1 of the first image. It is possible to also reserve for a second pixel, for example the fourth pixel P 4 of the matrix of the display device, the light intensity signal S 14 that makes it possible to display the fourth pixel of the first image. Finally, it is possible to reserve for the other two pixels, that is to say, for example, the second and third pixels P 2 , P 3 of the matrix of the display device, the signals intended for the pixels of the arrangement concerned of the second image that correspond thereto, that is, respectively, the light intensity signals S 22 and S 23 . Such an exemplary arrangement is particularly suited to the cases where the second image is two-color. For example, colored filters can be assigned to the second and third pixels P 2 , P 3 of all the arrangements of pixels of the matrix of the display device.
[0042] Advantageously, the colored filters associated with the second and third pixels P 2 , P 3 may be of colors which, in combination, make it possible to visually restore the color associated with the first pixel P 1 . For example, the colored filters associated with the second and third pixels P 2 , P 3 may be of two complementary colors, so that, by addition, they can restore the white color. The colored filters associated with the second pixels P 2 of the arrangements forming the matrix of the display device may, for example, be of red color, and the filters associated with the third pixels P 3 may, for example, be of cyan color.
[0043] Practically, the display of the duly merged image can, for example, be implemented via the following operations, performed by means of the controller of the display device:
a first operation of mapping the first image to the display device, the controller then applying the light intensity signals S 11 and S 14 respectively to the first and fourth pixels P 1 and P 4 of all the arrangements of pixels forming the display device; a second operation of mapping the second image to the display device, the controller then applying the light intensity signals S 22 and S 23 respectively to the second and third pixels P 2 and P 3 of all the arrangements of pixels forming the display device. Since the second image consists of two colors, the mapping may consist in mapping the first color to the submatrix consisting of the second pixels P 2 , that is to say on a resolution corresponding to a quarter of the resolution of the matrix of the display device, and in the mapping of the second color to the submatrix consisting of the third pixels P 3 , that is to say on a resolution that also corresponds to a quarter of the resolution of the matrix of the display device.
[0046] Advantageously, for the pixels of the second image for which the light intensity signals S 22 and S 23 respectively for the second and third pixels P 2 and P 3 are below a determined threshold value, that is to say where the second image is not visible, or is only barely visible, the second operation may be replaced with an alternative operation. This alternative operation may consist in applying to the second and third pixels of the matrix of the display device, for example for the pixels of the matrix of the display device that correspond to pixels of the second image intended to be displayed with a signal for which the light intensity is situated below the threshold, light intensity signals for example determined by the controller, corresponding to a combination of the values of the light intensity signals S 12 and S 13 of the first image. For example, it is possible to apply to the pixels P 2 and P 3 respectively the signals S 2 and S 3 , the values of which are defined by the following relationships:
[0000] S 2= a *( S 12+ S 13)/2,
[0000] S 3= b *( S 12+ S 13)/2;
[0000] a and b being real parameters, the sum of which equals 2.
[0047] Advantageously, the parameters a and b can be chosen so as to generate, by combining the light of the pixels P 2 and P 3 , the same color as those of the pixels P 1 and P 4 . It is obviously possible to envisage applying more complex formulae for the combination of the two signals S 2 and S 3 , these being able to be linear or nonlinear relationships.
[0048] This may prove particularly advantageous when the useful part of the second image covers only a part of the surface thereof, notably in the case where the second image represents a symbol or textural information.
[0049] Also advantageously, means for reinforcing the contrast of the merged image may be implemented, for example by means of the controller of the display device.
[0050] In fact, the color or colors of the second image may appear saturated only on the parts of the merged image for which the background of the first image is relatively dark. On the lighter parts of the first image, the color of the pixels of the matrix of the display device conveying information relating to the second image, that is to say the second pixel P 2 in the case of the first example mentioned above and illustrated in FIG. 2 , or the second and third pixels P 2 and P 3 in the case of this second example mentioned above and illustrated FIG. 3 , may appear with little saturation, that is to say visually appear like a pastel color. The means for reinforcing the contrast of the merged image may make it possible to obtain a good saturation of the colors of the second image while keeping a maximum display area for the first image.
[0051] Thus, the contrast reinforcement means may be configured so as to correct the display of the first image as follows, given as an example which is not limiting on the present invention: in the case of the first example mentioned above, for the second pixels P 2 for which the light intensity signal is different from the light intensity signal corresponding to a black level, or else for which the quantified value is greater than a predetermined threshold value, it is possible to determine the quantified values of the light intensity signals S 1 , S 3 and S 4 to be applied respectively to the first, third and fourth pixels of the arrangements, for example according to the following relationship:
[0000] Si=b ·exp(− a·S 1 i )· S 1 i , for i= 1 ; 3 ; 4 ; (1)
[0000] in the case of the second example mentioned above, for the second and third pixels P 2 and P 3 for which the light intensity signal is different from the light intensity signal corresponding to a black level, or else for which the quantified value is greater than a predetermined threshold value, it is possible to determine the quantified values of the light intensity signals S 1 and S 4 to be applied respectively to the first and fourth pixels of the arrangements, for example according to the following relationship:
[0000] Si=b ·exp(− a·S 1 i )· S 1 i , for i= 1; 4, (2)
[0000] a and b in the relationships (1) and (2) above are parameters that can be defined and set by means of the controller according to the targeted applications, or even parameters than can be modified by a user, for example via external control means making it possible to modify the configuration of the controller.
[0052] It should be noted that other functions can be applied for the determination of the values of the signals to be applied, the important thing to remember here being that the function applied should allow for an attenuation of the light levels of the first image, without in any way attenuating too much the darker levels.
[0053] In practice, a display device according to one of the embodiments described previously may, for example, be based on a matrix display device associated with a controller, the controller being able, for example, to be integrated in the matrix, or else external thereto.
[0054] It is also possible, in an advantageous embodiment, for the display device to be based on a dedicated hardware architecture, notably offering an advantage in terms of lower consumption in operation. An exemplary hardware architecture may be based on a matrix of pixels associated with two controllers, as described hereinbelow with reference to FIG. 4 , illustrating an exemplary embodiment of a matrix display device according to one embodiment of the invention.
[0055] A matrix display device 40 may, for example, comprise a mosaic of a plurality of arrangements of four pixels P 1 , P 2 , P 3 , P 4 . The matrix display device 40 is thus particularly suited to the first embodiment described previously with reference to FIG. 2 .
[0056] A first controller 41 , for example integrated in the structure containing the matrix, may be interfaced, via physical connection lines, with three pixels of each arrangement: the pixels P 1 , P 2 , P 3 in the example illustrated in FIG. 4 .
[0057] A second controller 42 , for example also integrated in the structure containing the matrix, may be interfaced, via physical connection lines, with the remaining pixel of each arrangement: the pixel P 4 in the example illustrated by the in FIG. 4 .
[0058] In this way, a video stream intended for a display on the matrix display device 40 can be displaced in interleaved manner, in the form of a first video stream generated by the first controller 41 , and of a second video stream generated by the second controller 42 . In such a configuration, each pixel is formed by one or more pixels (three in the example illustrated in FIG. 4 ) driven by the first controller 41 , and one or more pixels (one in the example of FIG. 4 ) being driven by the second controller 42 . Generally, the pixels dedicated respectively to the display of the first and the second image may be designed so as to emit different colors, by being, for example, associated with filters of dedicated colors. For example, the pixels dedicated to the display of the first image may be designed so as to emit a single first color, the pixels dedicated to the display of the second image being designed so as to emit a single second color, different from the first color.
[0059] In a typical exemplary application, the displayed image may have a definition of 800×500 pixels, the first image having, for example, an identical definition and giving a monochrome illustration of the visible field, and the second image having, for example, a definition four times lower, that is to say 400×250 pixels 2 , and illustrating, for example, the infrared field. In this typical configuration and according to the example illustrated in FIG. 4 , the pixels P 4 of the arrangements forming the matrix are, for example, associated with a filter of red color.
[0060] Another advantage obtained by such a device is that the two video streams generated by each of the two controllers 41 , 42 can have different definitions. Similarly, the two video streams can have different refresh frequencies. This way, the overall consumption of the matrix display device 40 is minimized.
[0061] Practical exemplary embodiments of the present invention are described hereinbelow.
[0062] According to a first example, the image displayed by the matrix display device may combine a first image originating from a night vision sensor with a second graphical image, for example generated by a microcontroller or a microcomputer. The first image may, for example, be a monochrome image, with a definition of 2000×2000 pixels, the color displayed being, for example, white or a first color C 1 . The second image may consist of graphical information (for example, icons, cursors, menus, etc.) or textual information (position, time and other such information), the color displayed being, for example, red, or else a second color C 2 different from the first color C 1 .
[0063] In this first example, the matrix display device may comprise a video controller, for example of FPGA type, a video interface with the night vision sensor, a video interface with the microcontroller or microcomputer for the display of the second image, an output interface with the matrix of pixels, the latter forming a dedicated display panel comprising arrangements of four pixels in squares. The definition of the matrix of pixels can then be 2000×2000 pixels, the arrangements of four pixels P 1 to P 4 consisting of three pixels P 1 , P 3 and P 4 emitting in the white color or in the first color C 1 , the remaining pixel P 2 emitting in the red color or in the second color C 2 .
[0064] The matrix of pixels may be formed by a microdisplay of OLED type with active matrix with white emitters (or emitters in the first color C 1 ), a red colored filter (or a filter of the second color C 2 ) being associated with the pixels intended for the display of the second image, or else these pixels being associated with red emitters or emitters in the second color C 2 .
[0065] According to this first example, the combined display of the two images may then consist of a display of the first image on the matrix of 2000×2000 pixels with one pixel out of every four (the pixels P 2 ) omitted. With S 11 , S 12 , S 13 and S 14 designating the intensity signals corresponding to the first image to be applied respectively to the pixels P 1 , P 2 , P 3 , P 4 , S 11 is applied to the pixel P 1 , S 13 to the pixel P 3 and S 14 to the pixel P 4 . The second image can then be displayed on the remaining pixels P 2 , by applying the signal S 22 (intensity signal corresponding to the second image).
[0066] Depending on the intensity of the first image, the second image may appear more or less saturated. In this first example, the red of the second image may appear pink on a light background (that is to say, the first image). To compensate this phenomenon, a local correction of the intensity of the first image can be performed, around display areas of the second image, that is to say in places where the intensity of the second image is different from zero, or else is above a determined threshold. As is described previously, in order not to excessively degrade the color saturation, the signals S 11 , S 13 and S 14 may be attenuated so that the attenuation is maximum if the intensity is strong (white background), and negligible when the intensity is weak (dark background), for example:
[0067] if S 22 > determined threshold value, then:
[0000] S 1 i (corr)=exp(− a*S 1 i )* S 1 i, i= 1, 3, 4,
[0000] a being a parameter to be determined according to the application. For example, if the image 2 contains symbols, a value of a of between 0.002 and 0.006 gives satisfactory results. Thus, the color of the first image remains fairly saturated, whereas the second image remains transparent; in other words, it is still possible to clearly distinguish the details of the first image behind the symbols of the second image.
[0068] According to a second example, the image displayed by the matrix display device may combine a first image originating from a night vision sensor with a second image derived from an infrared sensor targeting the same scene. The first image may, for example, be a monochrome image, with a definition of 2000×2000 pixels, the color displayed being, for example, white or a first color C 1 . The second image may also be monochrome, with a lower resolution: for example 480×480 pixels, the color displayed being, for example, red, or else a second color C 2 different from the first color C 1 .
[0069] In this second example, the matrix display device may comprise a video controller, for example of FPGA type, a first video interface with the night vision sensor, a second video interface with the infrared sensor, an image processing unit for performing the mapping of the second image, that is to say, the adaptation of the definition thereof, dictated by the infrared sensor, to the resolution of the matrix of pixels reserved for the display of the second image (for example 1000×1000 pixels if one pixel in every four is used for this purpose, as is explained hereinbelow), an output interface with the matrix of pixels, the latter forming a dedicated display panel comprising arrangements of four pixels in squares. The definition of the matrix of pixels may then, like the first example described previously, be 2000×2000 pixels, the arrangements of four pixels P 1 to P 4 consisting of three pixels P 1 , P 3 and P 4 emitting in the white color or in the first color C 1 , the remaining pixel P 2 emitting in the red color or in the second color C 2 .
[0070] The matrix of pixels may also be formed by a microdisplay of OLED type with active matrix with white emitters (or emitters in the first color C 1 ), a red colored filter (or a filter of the second color C 2 ) being associated with the pixels intended for the display of the second image, or else these pixels being associated with red emitters, or emitters in the second color C 2 .
[0071] The combined display of the two images can be produced in a way similar to the first example described previously. In order to obtain a good visibility on both images, it is important in this second example to apply the intensity correction to the first image from a certain threshold of intensity of the second image only, and to apply the parameter a appropriately.
[0072] It should be noted that all the embodiments described hereinabove apply to the combined display of two images. However, a matrix display device according to the present invention may also display a plurality of combined images, with arrangements of pixels in which pixels are dedicated to different images out of the plurality of images.
[0073] Thus, according to a third example, in a manner similar to the second example described previously, the image displayed by the matrix display device may combine a first image originating from a night vision sensor with a second image derived from an infrared sensor targeting the same scene, but also with a third image, for example generated by a microcontroller or a microcomputer, like the second image in the first example described previously. The first image may, for example, be a monochrome image, with a definition of 2000×2000 pixels, the color displayed being, for example, white or a first color C 1 . The second image may also be monochrome, with lower resolution: for example 480×480 pixels, the color displayed being, for example, red, or else a second color C 2 different from the first color C 1 . The third image may consist of graphical information (for example, icons, cursors, menus, etc.) or textual information (position, time or other such information), the color displayed being, for example, cyan, or else a third color C 3 different from the first color C 1 and from the second color C 2 .
[0074] In the third example, the matrix display device may comprise a video controller, for example of FPGA type, a first video interface with the night vision sensor, a second video interface with the infrared sensor, a third video interface with the microcontroller or microcomputer for the display of the second image, an image processing unit for producing the mapping of the second image like in the second example described previously, an output interface with the matrix of pixels, the latter forming a dedicated display panel comprising arrangements of four pixels in squares. The definition of the matrix of pixels may then be 2000×2000 pixels, the arrangements of four pixels P 1 to P 4 consisting of two pixels P 1 and P 4 emitting in the white color or in the first color C 1 , the pixel P 2 being dedicated to the display of the second image and emitting in the red color or in the second color C 2 , and the pixel P 3 emitting in the cyan color or in the third color C 3 , and being dedicated to the display of the third image.
[0075] The matrix of pixels may be formed by a microdisplay of OLED type with active matrix with white emitters (or emitters in the first color C 1 ), a red colored filter (or a filter of the second color C 2 ) being associated with the pixels intended for the display of the second image, or else these pixels being associated with red emitters or emitters in the second color C 2 , a cyan colored filter (or filter of the third color C 3 ) being associated with the pixels intended for the display of the third image, or else these pixels being associated with emitters in cyan or in the third color C 3 .
[0076] According to this third example, the combined display of the three images may then consist of a display of the first image on the matrix of 2000×2000 pixels with two pixels in every four (the pixels P 2 and P 3 ) omitted. With S 11 , S 12 , S 13 and S 14 designating the intensity signals corresponding to the first image to be applied respectively to the pixels P 1 , P 2 , P 3 , P 4 , S 11 is applied to the pixel P 1 and S 14 to the pixel P 4 . The second image may then be displayed on the pixels P 2 , by applying the signal S 22 (intensity signal corresponding to the second image), and the third image may be displayed on the pixels P 3 , by applying the signal S 33 .
[0077] Depending on the intensity of the first image, the second and third images may appear more or less saturated. Thus, the red of the second image may appear pink on a light background (that is to say, the first image). To compensate this phenomenon, a local correction of the intensity of the first image can be performed, around areas of display of the second and of the third images, that is to say in places where the intensity of the second or the third image is different from zero, or else is above a determined threshold. The signals S 11 and S 14 can thus be attenuated such that the attenuation is maximum if the intensity is strong (white background), and negligible when the intensity is weak (dark background), for example:
if S 22 > first determined threshold value OR S 33 > second determined threshold value, then:
[0000] S 1 i (corr)=exp(− a*S 1 i )* S 1 i, i= 1, 4,
[0000] a being a parameter to be determined according to the application. For example, if the image 2 contains symbols, a value of a between 0.002 and 0.004 gives satisfactory results. Thus, the color of the first image remains fairly saturated, whereas the second and third images remain transparent.
[0079] In order to further enhance the efficiency of the first image, it is possible, as described previously, to use the pixels P 2 and P 3 for the display of the first image in places thereof where no overlay of the second or third image is present, or else in places of the first image where the intensity of the overlays remains below a determined threshold. By having chosen complementary colors for the pixels P 2 and P 3 of the arrangements, that is to say that their superimposition generates the white color, a combination of P 2 and P 3 may replace a white pixel. It is then possible to display on the pixels P 2 and P 3 the following signals:
[0080] if S 22 < third threshold value AND S 33 < fourth threshold value, then:
[0000] S 2=( S 12+ S 13)/2
[0000] S 3=( S 12+ S 13)/2
[0000] In this way, it is possible to profit from a maximum of resolution for the first image.
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A matrix display device with a definition determined by a plurality of pixels, the matrix display device including at least one controller suitable for producing display light intensity signals for each of the pixels; and a matrix of pixels organized in a mosaic of a plurality of identical arrangements of a determined number of pixels, wherein a first number of pixels of an arrangement are dedicated to display of a first image and receives the light intensity signals associated with the pixels of the first image that correspond thereto, one or more other pixels of the arrangement are dedicated to display of a second image and receiving light intensity signals associated with the pixels of said second image that correspond thereto, the matrix display device producing the merged display of the first image and of the second image, the two images being, if necessary, redimensioned by scaling means.
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CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
None.
BACKGROUND
The present disclosure relates generally to the field of window construction. Some window designs include a frame that houses the glazing of the window and a glazing bead that couples to the frame to enclose the glazing and provide decorative features. When the window is installed in a building, the outer glazing bead faces the exterior of the building. Water or other fluids or debris may collect in interior spaces of the frame between the frame, glazing, and glazing bead. It would be advantageous to provide drainage for a window frame with inconspicuous outlets.
SUMMARY
One embodiment of the invention relates to an apparatus for a window frame. The apparatus includes a window frame having a lower frame portion; a window glazing supported by the lower frame portion; a glazing bead; and at least two connectors operatively connecting the glazing bead to the lower frame. The connectors are spaced apart defining a fluid pathway allowing fluid to escape from the lower frame.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not restrictive of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features, aspects, and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below.
FIG. 1 is an isometric section view of a window, according to an exemplary embodiment.
FIG. 2 is an exploded view of the glazing bead for the window of FIG. 1 .
FIG. 3 is a section view of the window of FIG. 1 , taken generally along line 3 - 3 in FIG. 1 .
FIG. 4 is an isometric section view of the window of FIG. 1 with a portion of the glazing bead removed.
FIG. 5 is a detailed isometric view of the window of FIG. 2 , taken generally along line 5 - 5 in FIG. 4 .
FIG. 6 is a left side view of the window of FIG. 1 .
DETAILED DESCRIPTION
Referring to FIG. 1 , a window 10 includes a frame 11 surrounding at least one pane of glazing or glass 18 . Window 10 will be described herein as a generally rectangular frame including a lower frame portion 12 and a side frame portion 14 that is angled relative to lower frame portion 12 . Window 10 may further include a second side frame portion and an upper frame portion, not shown in FIG. 1 . According to a preferred embodiment, window 10 is a rectangular body with a horizontal lower frame portion 12 , a horizontal upper frame portion, and two vertical side frame portions 14 .
Lower frame portion 12 and side frame portion 14 may be made of wood, a vinyl material, a composite material, a plastic material, an aluminum material, a steel material, an combination thereof, or any other material suitable for a window. As shown in FIG. 1 , according to one embodiment, the components of frame are formed with an extrusion process from a suitable material such as a metal (e.g., aluminum, etc.) or a polymer (e.g., vinyl, etc.).
According to various exemplary embodiments, glazing 18 may include a single pane of glass, double panes of glass, triple panes of glass or any other number of panes. Any space between multiple panes of glass 18 may be filled with air, argon, krypton, a vacuum, or any other substance. Glazing 18 may be made of any type of glass material (e.g., soda lime glass, alkali silicate glass, etc.) of any thickness and may include any features of past, present, or future design (e.g., a low-E coating, lamination, tinting, impact resistance, shatter resistance, etc.) Glazing 18 may also be formed of any other type of window material such as plastic.
A glazing bead 20 is coupled to frame 11 around the periphery of glazing 18 . Glazing bead 20 is configured to secure glazing 18 in frame 11 and may also be designed as a decorative trim element to provide a pleasing appearance. Glazing bead 20 may be formed from a material used to form frame 11 such as wood, a vinyl material, a composite material, a plastic material, an aluminum material, a steel material, a combination thereof, or any other suitable material.
According to an exemplary embodiment, glazing bead 20 may include a flexible lip 21 to create a better seal against the surface of glazing 18 . Flexible lip 21 may be formed of the same material as the main body of glazing bead 20 and be flexible because of a reduced thickness or may be a different material that is coextruded, applied as a coating, or otherwise coupled to the main body of glazing bead 20 .
Glazing bead 20 may comprise several individual elements or may be a single, continuous element that is shaped (e.g., by bending) to extend about the periphery of glazing 18 . Referring to the exploded view in FIG. 2 , according to one exemplary embodiment, glazing bead 20 includes a lower glazing bead 22 and a side glazing bead 24 . Similar to frame 11 , glazing bead 20 further includes a second side glazing bead and an upper glazing bead not shown.
Referring still to FIGS. 1-3 , glazing bead 20 includes a front surface 26 (e.g., first surface, vertical surface, etc.) and a beveled surface 28 (e.g., second surface, angled surface, etc.). According to an exemplary embodiment, lower glazing bead 22 and side glazing bead 24 are coupled together to form a faux-butt joint 30 . Faux-butt joint 30 appears to an observer to be a butt joint (e.g., a joint with the components meeting at a face normal to the front face), however, referring to FIG. 3 , lower glazing bead 22 includes an angled cut 32 that is configured to mate with beveled surface 28 of side glazing bead 24 . Coupling lower glazing bead 22 and side glazing bead 24 along the angled mating surface between angled cut 32 and beveled surface 28 facilitates forming a better seal by increasing the area of contact between lower glazing bead 22 and side glazing bead 24 .
Referring now to FIG. 4 , connectors 40 are provided to couple glazing bead 20 to frame 11 . Connectors 40 are generally flat, elongated members that are received in a slot 15 in frame 11 and a slot 25 in glazing bead 20 . In one embodiment connectors 40 are continuous along the upper frame portion and side frame portions 14 . The continuous connectors 40 secured to the upper frame portion and side frame portions connect the glazing bead 20 and connect on the upper frame portion and side frame portions provide a water shed or seal to prevent leaks. However, in one embodiment multiple connectors 40 may be used along the bottom of lower frame portion 12 . The length, number, and spacing of connectors 40 may be varied based on the requirements of frame (e.g., the force needed to retain glazing 18 , etc.). The spacing between connectors 40 along the lower frame portion 12 on the exterior provides the route through which fluid may exit. Connectors 40 are also provided to couple an interior covering 92 to an interior surface of the frame. Note that connectors 40 on the lower frame portion 12 on the interior side of the frame that connect covering 92 provide spacing 55 . Referring to FIG. 4-FIG . 6 connectors 40 are separated by a space 55 along a linear axis being parallel to a plane defined by the window glazing 18 . A continuous connector 40 may be used on the interior lower frame portion 12 to connect covering 92 . Interior covering 92 may be formed of wood, wood composite, plastic, fiberglass, vinyl or other decorative covering material.
Referring to FIG. 5 , a portion of window 10 is illustrated in greater detail, according to an exemplary embodiment. Connector 40 is configured for mating with frame 11 and glazing bead 20 with one or more barbs 42 . Either end of connector 40 includes multiple flexible barbs 42 (e.g., flaps, protrusions, fins, etc.) to aid in mating with frame 11 and glazing bead 20 . Barbs 42 may extend from either or both faces of connector 40 . As shown, barbs 42 are angled away from the distal edges of connector 40 relative to the main body of connector 40 .
Slots 15 and 25 are sized such that barbs 42 are compressed and otherwise deformed when connector 40 is inserted into slot 15 and/or slot 25 . The distortion of barbs 42 when connector 40 is inserted into slots 15 and 25 is resisted by an outward biasing force. The outward force provided by barbs 42 retains connector 40 in slots 15 and 25 and therefore couples glazing bead 20 to frame 11 and to secure glazing 18 in frame 11 . The retaining force of barbs 42 is sufficient to overcome opposing forces such as the weight of glazing bead 20 , wind, rain, etc. However, the retain force provided by barbs 42 can be overcome by a sufficient outward force, allowing glazing bead 20 to be removed for maintenance or replacement.
While barbs 42 are shown as being generally planar members of a single size and relative orientation, many variations are possible while still providing sufficient force for coupling frame 11 and glazing bead 20 . For example, instead of a continuous body extending the length of connector 40 , barb 42 may comprise several discrete elements. Barbs 42 may be oriented at a different angle or may have a different cross-sectional shape (e.g., triangular, rounded, etc.). Barbs 42 may vary in size on either side of connector to mate with slots of different sizes in frame 11 and glazing bead 20 . Further, barbs 42 may vary in size between the top and bottom faces of connector 40 .
The main body of connector 40 and barbs 42 may be made of different materials and integrally formed with a suitable process such as coextrusion. According to various exemplary embodiments, barbs 42 may be made of flexible polyvinyl chloride (PVC), thermoplastic elastomer (TPE), flexible urethane, a rubber based material, or a similar flexible extruded material. According to various exemplary embodiments, connector 40 may be made of PVC, polypropylene, acrylonitrile butadiene styrene (ABS), or any other rigid extrudable material.
Referring now to FIG. 6 , an end view window 10 is shown according to an exemplary embodiment, showing the structure below glazing 18 . Lower frame portion 12 may be a substantially hollow body (e.g., formed as an extruded aluminum or vinyl body, etc.) defined at least partially by an top face 60 , a first wall 62 , a first shelf 64 , a second wall 66 , a second shelf 68 , and a third wall 70 . Lower frame portion may further include an interior wall 72 extending along the inside face of glazing 18 . Wall 72 provides a physical stop that helps to secure and locate glazing 18 in frame 11 .
Glazing 18 is generally supported above top face 60 of lower frame portion 12 with support structures or spacers. Below the lower edge of glazing 18 is formed an open volume 50 (e.g., space, chamber, cavity, etc.), which is substantially enclosed by lower frame portion 12 and glazing bead 20 . Volume 50 is generally defined by glazing 18 , glazing bead 20 and top face 60 and wall 72 of lower frame portion 12 .
While the seal formed around glazing 18 by glazing bead 20 prevents the majority of water from passing through, moisture may still enter volume 50 . For example, moist air may enter volume 50 , allowing water to condense in volume 50 . A glazing compound 56 is placed between glazing bead 20 and glazing 18 to secure glazing bead 20 to glazing 18 . Glazing compound may include other materials and/or tape known in the art including but not limited to silicon compound, one hundred percent silicon, or a hot melt material. Wall 72 prevents water from flowing out of volume 50 into the interior space of the building or enclosure including window 10 . Glazing compound 56 is also located between wall 72 and glazing 18 . Glazing compound 56 assists in keeping water from entering the interior of the structure as well as from entering the interior of frame regions 50 and 86 .
To allow water, other fluids, or debris to exit volume 50 , flow paths 54 are formed by the components of window 10 . Flow paths 54 are formed by the arrangement of lower frame portion 12 , glazing bead 20 , and connectors 40 and does not require any additional openings (e.g., channels, holes, slots, etc.) to be formed in components. The weep or exit of flow paths 54 is provided inconspicuously between the lower edge 84 of glazing bead 20 and lower frame portion 12 .
According to an exemplary embodiment, flow path 54 is formed between glazing bead 20 and lower frame portion 12 . Connectors 40 couple glazing bead 20 to lower frame portion 12 such that glazing bead 20 creates a seal against glazing 18 while maintaining a separation 52 from first wall 62 of lower frame portion 12 . Referring to FIG. 4 , instead of a single component extending the entire length of lower frame portion 12 , connectors 40 are provided as multiple, separate components separated by gaps 56 . Flow path 54 extends between glazing bead 20 and lower frame portion 12 through gaps 56 between connectors 40 .
A second volume 80 is formed between lower frame portion 12 and glazing bead 20 below first volume 50 . Volume 80 is generally defined by first wall 62 and first shelf 64 of lower frame portion 12 and glazing bead 20 . After flowing out of volume 50 , fluids and debris enter volume 80 . Glazing bead 20 is coupled to lower frame portion 12 by connectors 40 such that a gap 82 is formed between the lower edge 84 of glazing bead 20 and first shelf 66 of lower frame portion 12 . Gap 82 is the only portion of flow path 54 that is visible when window 10 is assembled and installed.
Flow path 54 directs fluids and debris out of the interior of window 10 without entering lower frame portion 12 . Fluids and debris are allowed to escape volume 80 through gap 62 , flow down second wall 66 of lower frame portion 12 , over second shelf 68 , down a third wall 70 , and escape into the exterior environment. Top face 60 , first shelf 64 , and second shelf 68 of lower frame portion 12 may be pitched or angled to facilitate the flow of fluids and debris to the exterior space.
Volumes 50 and 80 and flow paths 54 direct any fluids or debris that may collect in the interior of window 10 to the exterior space, reducing the likelihood of damage to window 10 caused by the fluids or debris (e.g., by expansion of freezing water, etc.). The formation of flow paths 54 by the arrangement of components is advantageous because openings formed in components can be obstructed by debris, reducing the ability of fluids to escape volume 50 . Further, openings formed in components of window 10 to create flow paths may require additional manufacturing steps (e.g., machining, stamping, etc.), increasing manufacturing time and cost of window 10 .
A third volume 86 is located below first volume 50 and second volume 80 and is sealed such that no water is permitted to enter into volume 86 . Third volume 86 is formed by top face 60 , first wall 62 , first shelf 64 , a second wall 66 , a second shelf 68 , a third wall 70 , a bottom wall 88 and a fourth wall 90 .
For purposes of this disclosure, the term “coupled” means the joining of two components directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally defined as a single unitary body with one another or with the two components or the two components and any additional member being attached to one another. Such joining may be permanent in nature or alternatively may be removable or releasable in nature.
While window 10 is described as rectangular body, in other exemplary embodiments, window 10 and glazing 18 may differently shaped and still include construction that provides an inconspicuous weep. For example, window 10 may be square, another polygonal shape (e.g., hexagonal, octagonal, etc) or rounded. Regardless of the overall shape of window 10 , the lower portion of frame 11 and glazing bead 20 may be arranged such flow paths are formed to allow fluids and debris to flow out of the lower portion of window 10 .
The arrangement and construction of the frame members and glazing bead for window 10 provides an inconspicuous weep that can be adapted to many other styles of windows. While window 10 is shown in the FIGURES as a picture window frame, in other embodiments, window 10 may be of another construction, such as a casement window, a double hung window, or a bay window.
The present disclosure has been described with reference to exemplary embodiments, however, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the disclosure. For example, although different example embodiments may have been described as including one or more features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example embodiments or in other alternative embodiments. Because the technology of the present disclosure is relatively complex, not all changes in the technology are foreseeable. The present disclosure described with reference to the example is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted a single particular element may also encompass a plurality of such particular elements.
It is also important to note that the construction and arrangement of the elements of the system as shown in the exemplary embodiments is illustrative only. Although only a certain number of embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited.
Further, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the assemblies may be reversed or otherwise varied, the length or width of the structures and/or members or connectors or other elements of the system may be varied, the nature or number of adjustment or attachment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability. Accordingly, all such modifications are intended to be included within the scope of the present disclosure. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the spirit of the present subject matter.
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One embodiment of the invention relates to an apparatus for a window frame. The apparatus includes a window frame having a lower frame portion; a window glazing supported by the lower frame portion; a glazing bead; and at least two connectors operatively connecting the glazing bead to the lower frame. The connectors are spaced apart defining a fluid pathway allowing fluid to escape from the lower frame.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national stage entry under 35 U.S.C. §371(b) of International Application No. PCT/ES2011/070912, filed Dec. 29, 2011, which claims the benefit of Spanish Patent Application Serial No. P201031984, filed Dec. 29, 2010, the disclosures of both of which are hereby incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to a biological culture of a strain of the species Pseudomonas graminis and to the use of said strain as an antagonist for the biocontrol of foodborne pathogenic bacteria in fruit. It also relates to a method for treating fruit which comprises the step of applying a preparation that comprises said culture to the fruit.
BACKGROUND OF THE INVENTION
Fresh-cut fruit or minimally-processed fruit is a product that has recently appeared in markets. This fruit is subjected to a minimum processing which involves the washing, peeling, cutting, disinfection and packaging thereof in a passive or active modified atmosphere, to be finally stored under refrigeration conditions.
Fresh-cut fruit is a food product that is very susceptible to physical, chemical and biological alterations, which deteriorates at a higher rate than whole fruit. In fresh-cut fruit, respiration and metabolic processes are accelerated as a result of handling, for which reason it is essential to store the product in a modified atmosphere and keep it under refrigeration conditions.
Current regulations apply very strict microbiological criteria to fresh-cut fruit, in order to reduce to the minimum food toxi-infections or illnesses caused by the ingestion of fruit contaminated with bacteria such as Salmonella spp., Listeria spp. or Escherichia coli O157:H7 types.
Currently, in order to guarantee the safety of minimally-processed food products, treatments that involve washing the fruit with water with added sodium hypochlorite are usually applied. These treatments reduce the microbial load of the products, but have the disadvantage that they may leave a chlorine residue which facilitates the formation of substances that may be carcinogenic. Moreover, the treatment with hypochlorite does not prevent the growth of microorganisms during storage of the fruit or during the shelf life of the product.
The biocontrol of foodborne pathogenic bacteria in minimally processed products is a very desirable alternative to treatments with sodium hypochlorite. However, in order for this alternative to be viable, it is essential to find antagonistic microorganisms that are effective against any of the three aforementioned types of pathogenic bacteria ( Salmonella spp., Listeria spp. and Escherichia coli O157:H7), both at room temperature and under refrigeration and modified atmosphere conditions. Moreover, it is desirable for these antagonists to be innocuous for both humans and vegetables, since, otherwise, they could harm the consumers or the treated product.
In the state of the art, antagonists have been disclosed for the biocontrol of foodborne pathogenic bacteria in fruit (“ Biological control of postharvest decays of apple can prevent growth of Escherichia coli O 157 :H 7 in apple wounds”, Janisiewicz, W. et al. JOURNAL OF FOOD PROTECTION 62 (12): 1372-1375. 1999, and “ Biocontrol of the food - borne pathogens Listeria monocytogenes and Salmonella enterica serovar Poona on fresh - cut apples with naturally occurring bacterial and yeast antagonists”, Leverentz, B. et al. APPLIED AND ENVIRONMENTAL MICROBIOLOGY 72 (2): 1135-1140. 2006).
However, the antagonists used do not belong to the species Pseudomonas graminis and, moreover, none of them is effective against any of the microorganisms Salmonella spp. Listeria spp. and Escherichia coli O157:H7 either at room temperature or under refrigeration conditions.
SUMMARY DESCRIPTION OF THE INVENTION
A first objective of the present invention is to provide a substantially pure biological culture of a new strain of the species Pseudomonas graminis deposited with number CBS136973 at the depositary institution “Centraalbureau voor Schimmelcultures (CBS) in Utrecht, Netherlands.
A second objective is to provide a substantially pure biological culture of a new strain of the species Pseudomonas graminis deposited with number CBS136973, to be used as an antagonist for the biocontrol of foodborne pathogenic bacteria in fruit intended for human consumption.
A third objective of the present invention consists of the use of the aforementioned biological culture of the new strain as an antagonist for the biocontrol of foodborne pathogenic bacteria in fruit intended for human consumption.
A fourth objective involves a method for treating fruit which comprises the step of applying a preparation that comprises the aforementioned biological culture of the new strain to the fruit.
It has been observed that the isolated new strain shows great effectiveness as an antagonist against foodborne pathogenic bacteria in fruit, for a wide range of pathogens and fruits, at room temperature, in a modified atmosphere and under refrigeration conditions. The application thereof makes it possible to reduce the growth of pathogens during the useful life of the product, especially when the cold chain is broken.
In the present invention, foodborne pathogenic bacteria are understood to mean pathogenic bacteria that produce food toxi-infections or illnesses caused by the ingestion of contaminated foodstuffs, for example, fruit contaminated with pathogenic bacteria of the Salmonella spp., Listeria spp. or Escherichia coli O157:H7 types.
The new strain of the species Pseudomonas graminis (Behrendt et al. 1999 1 ) was isolated from the surface of a “Golden Delicious” apple by means of washing with sterile water, followed by immersion in saline-peptone solution (peptone, 1 g/l; NaCl, 0.85 g/l), sonication in an ultrasound bath for 10 min and planting the washing liquid in NYDA culture medium (Nutrient broth, 8 g/l; yeast extract, 5 g/l; dextrose, 10 g/l, and agar, 15 g/l), and subsequent incubation at 25° C. for 3 days.
The new strain culture has been deposited by one of the applicants, in accordance with the specifications of the Budapest Treaty on the recognition of the deposit of microorganisms for purposes of patent procedure, at the international depositary authority “Centraalbureau voor Schimmelcultures (CBS)”, with headquarters at Uppsalalaan 8, 3584 CT Utrecht, Netherlands. The deposit number assigned was CBS136973.
Isolate CBS136973 was identified by the partial sequencing of the region 16S rRNA: Pseudomonas sp., and by the full sequencing of the region 16S rRNA: Pseudomonas graminis (Behrendt et al., 1999 1 ).
Morphological and Biochemical Characteristics of the New Strain
Strain CBS136973 is a gram-negative, non-spore-forming, oxidase-negative, catalase-positive, mobile, aerobic bacillus . In plates, the colonies are yellow, with a circular shape and whole edges.
Strain CBS136973 has the biochemical characteristics listed in Table 1 and is phenotypically differentiated from other Pseudomonas species by the tests shown in Table 2.
The growth temperature ranges between 5° C. and 30° C., with the optimum ranging between 25° C. and 30° C. It does not grow at 33° C. or 0° C.
Growth on plates may be performed in NA culture medium (Nutrient Agar: 5 g/l Tryptone, 3 g/l meat extract, 15 g/l agar), TSA (Tryptic soy broth: 15 g/l tryptone, 5.0 g/l soy peptone, 5.0 g/l sodium chloride and 15 g/l agar, pH 7.3) or NYDA (Nutrient broth: 8 g/l; yeast extract, 5 g/l; dextrose, 10 g/l and agar, 15 g/l).
Growth in liquid may be performed in TSB culture medium (Tryptone soy broth: 17.0 g/l pancreatic digest of casein, 3.0 g/l enzymatic digest of soybean meal, 5.0 g/l sodium chloride, 2.5 g/l dipotassium hydrogen phosphate, 2.5 g/l glucose, pH 7.3). NB medium (Nutrient broth: 10 g/l tryptone, 5 g/l meat extract, 5 g/l sodium chloride, pH 7.2) may also be used.
The growth of strain CBS136973 in TSB or NB medium under aerobic conditions, under stirring and at a temperature ranging between 25° C. and 30° C., reaches a maximum population size at 20-24 h of incubation (generally between 1.9 and 2.9×10 9 colony-forming units (cfu)/ml), without there being large differences between the two culture media.
TABLE 1
Enzymatic tests of the API 20 NE biochemical strips -
Identification system for bacteria of the Biomerieux
label. Results after 24 h and 48 h at 30° C.
ACTIVE
Result
Result
TEST
COMPONENTS
Enzymatic reactions
24 h
48 h
NO 3
Potassium nitrate
Reduction of nitrates into
−
nd
nitrites
Reduction of nitrates into
−
nd
nitrogen
TRP
L-tryptophan
Formation of indol
−
nd
(TRyPtophan)
GLU
D-glucose
Fermentation (GLUcose)
−
nd
ADH
L-arginine
Arginine Dihydrolase
−
−
URE
Urea
Urease
−
−
ESC
Aesculin
Hydrolysis(β-glucosidase)
+
+
Ferric citrate
(aESCulin)
GEL
Gelatin(bovine
Hydrolysis (protease)
−
−
origin)
(GELatin)
PNG
4-nitrophenyl-βD-
β-galactosidase (Para-
+
+
galactopyranoside
NitroPhenyl-βD-
Galactopyranosidase)
GLU
D-glucose
Assimilation (GLUcose)
+
+
ARA
L-arabinose
Assimilation (ARAbinose)
+
+
MNE
D-mannose
Assimilation (MaNnosE)
−/w
+
MAN
D-mannitol
Assimilation (MANnitol)
v
+
NAG
N-acetyl-
Assimilation (N-Acetyl-
−
v
glucosamine
Glucosamine)
MAL
D-maltose
Assimilation (MALtose)
v
v
GNT
Potassium
Assimilation (potassium
+
+
gluconate
GlucoNaTe)
CAP
Capric acid
Assimilation (CAPric acid)
v
+
ADI
Adipic acid
Assimilation (ADIpic acid)
−
−
MLT
Malic acid
Assimilation (MaLaTe)
+
+
CIT
Trisodium citrate
Assimilation (trisodium
+
+
CITrate)
PAC
Phenylacetic acid
Assimilation (phenylACetic
−
−
acid)
(+ positive, − negative, w weak, v variable, nd not determined)
TABLE 2 Phenotypical characteristics that differentiate strain CBS124167 from other species of Pseudomonas . Strain Characteristic CBS124167 P. graminis a P. lutea P. rhizosphaerae Oxidase − b − − − Growth at + + + nd 6° C. Production of − − − − acid from glucose Utilisation of − − − + erythritol Utilisation of W + − + sorbitol Utilisation of − v + − xylitol Utilisation of − − + − melibiose Utilisation of − − − + rhamnose Hydrolysis of + + + − aesculin Hydrolysis of − v − − gelatin a The data for the reference species have been taken from Peix et al. (2003 3 , 2004 4 ) and Behrendt et al. (1999 1 ). b +: positive; −: negative; w: weak; v: variable reaction between strains of the same species; nd: data not available
Production of Anti-Microbial Substances
Experiments were performed in order to determine whether strain CBS136973 produces anti-microbial substances. To this end, the strain was grown in TSB medium at 30° C., for 20-24 h. A fraction of the culture obtained was reserved, which was called “culture, CUL” and contained cells as well as culture medium and possible metabolites produced during growth. The rest was centrifuged at 8000 rpm for 10 min, at 10° C. The pH of the supernatant was adjusted to 6.5 and it was sterilised by filtration (0.22 μm), to obtain a “neutral cell-free supernatant, NCFS”. The cellular fraction obtained following the centrifugation was re-suspended in sterile de-ionised water, centrifuged and washed two consecutive times in order to eliminate potential culture medium residues, to obtain only “cells, CEL”.
The effectiveness of the following three fractions: CUL, NCFS and CEL, against several indicator cultures: Escherichia coli O157:H7, Salmonella spp., Listeria innocua and Listeria monocytogenes was determined under in vitro conditions. To this end, Salmonella spp. and Escherichia coli O157:H7 were made to grow in TSB medium and Listeria spp. was grown in TYSEB medium (TSB supplemented with 6 g/l of yeast extract) at 37° C., for 18-20 h. 50 μl of each of the cultures obtained were added to tubes containing 10 ml of TSB ( Salmonella spp. and Escherichia coli O157:H7) or TYSEB medium ( Listeria spp.) containing 7.5 g/l of agar and tempered at 45° C.
The content of each tube (medium+indicator culture) was deposited on plates containing 20 g/l meat extract, 20 g/l of glucose and 15 g/l of agar. Once they were solidified, 5 ml of the CUL, NCFS or CEL were deposited and the plates were incubated at 30° C., for 20 h; thereafter, the presence or absence of an inhibition halo was indicated.
No inhibition of growth of the indicator pathogens was observed in those treatments where the neutral cell-free supernatant was inoculated; thus, we may rule out the production of anti-microbial substances by strain CBS136973 under the assay conditions.
The in vivo effectiveness of the supernatant against Escherichia coli O157:H7, Salmonella spp. and Listeria innocua was also assayed in cut apple, and it was compared to the effectiveness of the cells. It was observed that the cell-free supernatants have no effect on the pathogen, and even favour the growth thereof after 2 days of storage at 20° C.
Phytopathogenicity
It was also determined whether or not strain CBS136973 is phytopathogenic, capable of producing a hypersensitivity reaction in tobacco leaves, according to the methodology of Noval et al. 1991 2 . To this end, a suspension of 10 9 cfu/ml of the strain was prepared and injected in the veins of tobacco leaves using an insulin syringe. Water was used for the negative control and strain CPA-3 of Pantoea ananatis was used as a positive control, since this strain is phytopathogenic. The plants were kept at room temperature and periodical checks were performed in order to determine whether or not they presented symptoms of hypersensitivity, in the form of necrosis, yellowing of the infiltrated area or death of the leaves. No reaction was observed in the treated leaves, even with high doses of CBS136973 (10 9 cfu/ml). Therefore, strain CBS136973 is not phytopathogenic.
Survival in Gastric Juice Under Direct Contact and Inoculated in Apples
In order to evaluate the survival under direct contact, 50 ml of a suspension of 10 9 cfu/ml of strain CBS136973 were added in a solution of simulated saliva and gastric juice (6.2 g/l NaCl, 2.2 g/l KCl, 0.22 g/l of CaCl 2 and 1.2 g/l NaHCO 3 , 0.3 g/l pepsin; pH adjusted to 2.0, tempered at 37° C.) and incubated at 37° C., for 2 h. A sample was taken after 1 and 2 h. No viable cells of the strain of the present invention were detected, even after 10 min of contact.
In order to evaluate the survival in gastric juice of strain CBS136973 on apple, “Golden Delicious” apples were inoculated with strain CBS136973 at a dose of 10 7 cfu/ml by means of bath immersion for 2 min. They were allowed to dry, packaged in polypropylene containers and sealed with a polypropylene film with a thickness of 35 μm and a permeability to O 2 and CO 2 of 3500 cm 3 /m 2 *day*atm at 23° C., and a permeability to water vapour of 0.9 g/m 2 *day at 25° C. and 75% relative humidity, and stored at 5° C. After 0, 4, 7 and 14 days, 10 g were collected and subjected to a simulated gastric passage. To this end, they were mixed with 10 ml of artificial saliva solution (6.2 g/l NaCl, 2.2 g/l KCl, 0.22 g/l of CaCl 2 and 1.2 g/l NaHCO 3 ), tempered at 37° C. It was homogenised for 2 min and transferred to an Erlenmeyer flask with 80 ml of gastric juice (0.3 g/l pepsin; pH 2.0), and incubated at 37° C. for 2 h. Subsequently, the viable population of the strain was determined, by means of planting on NA medium.
No viable cells were observed in any of the samples analysed after 2 h of contact with the gastric juice. Therefore, it may be deduced that the strain of the present invention does not survive gastric passage. This is positive, since, even if the cells grow on the surface of the fruit during the storage thereof, said cells cannot cause any damage when the treated fruit is ingested, because they will not survive gastric transit. It is also worth mentioning that no references were found which relate the species Ps. graminis with cases of food toxi-infections.
Growth on the Fruit
It has been observed that strain CBS136973 is capable of growing on cut apples, peaches and melons at different temperatures, although the growth is much greater in melons, due to their lower acidity (higher pH). Growth has also been observed in fresh-cut apples under modified atmosphere conditions and under refrigeration temperature stored.
DETAILED DESCRIPTION OF THE INVENTION
It has been observed that strain CBS136973 is very effective against foodborne pathogenic bacteria in fruit, preferably, in fruit cut in pieces and, advantageously, against the microorganisms Salmonella spp., Listeria spp. and/or Escherichia coli O157:H7, which are the main ones in fruits and vegetables.
Thanks to this, strain CBS136973 may be used as an antagonist against any of said microorganisms, which favours the fulfillment of the microbiological criteria specified especially for fresh-cut fruit or minimally processed fruit, in order to prevent food toxi-infections or illnesses caused by the ingestion of fruit contaminated with bacteria belonging to Salmonella spp., Listeria spp. or Escherichia coli O157:H7 genera.
In particular, the effectiveness against Salmonella spp. has been observed for the species Salmonella choleraesuis , whereas the effectiveness against Listeria spp. has been observed for the species Listeria monocytogenes and Listeria innocua.
According to a first embodiment of the present invention, the strain of the present invention is used for biocontrol in fruit, preferably fruit cut in pieces, keeping the fruit at a temperature greater than 10° C., preferably a temperature equal to or greater than 20° C.
At room temperature, it has been observed that strain CBS136973 may slow down, and even reduce, the growth of any of the aforementioned microorganisms, even when these microorganisms are present on the fruit at a concentration equal to or greater than 10 3 cfu/g, which is a very high concentration, difficult to find in real conditions.
This use is particularly advantageous since it makes it possible to control the growth of pathogens in those cases where the fruit storage temperature is not the adequate one, or the cold chain of the product is broken during the storage or transport thereof, for example, due to maintenance problems in the fruit refrigeration equipment. It is very important for the strain to be effective at room temperature, since this is the temperature where the pathogenic microorganism can grow the most and, consequently, the risk for the consumer increases.
According to a second embodiment, the strain of the present invention is used for biocontrol in fruit, for example fruit cut in pieces, keeping the fruit under refrigeration conditions. Refrigeration conditions are understood to mean keeping the fruit at a refrigeration temperature equal to or lower than 10° C., preferably equal to or lower than 5° C.
Surprisingly, the effectiveness of strain CBS136973 against any of the microorganisms Salmonella spp., Listeria spp. and Escherichia coli O157:H7 has also been demonstrated at refrigeration temperatures, which are those set by the producer or distributor for storage of the fruit.
According to a third embodiment, the strain of the present invention is used for biocontrol in fruit, preferably fresh-cut fruit, keeping the fruit in a modified atmosphere. Modified atmosphere is understood to mean an atmosphere with a gas composition different from that of air, in order to improve the fruit storage conditions.
The strain of the present invention also shows effectiveness when the fruit is packaged in a modified atmosphere for the storage thereof. Thanks to this, the strain may be used under habitual commercialisation conditions; consequently, it is also possible to guarantee food safety under the conditions of supermarket or displays.
Advantageously, said fruit is a fruit with a pH ranging between 3 and 7, for example, fruit such as apple, peach and/or melon.
It has been observed that the growth of Salmonella spp., Listeria spp. or Escherichia coli O 157:H7 may occur in a wide range of fruits, despite the acidity conditions of certain fruits such as apples. It has also been observed that the growth of the aforementioned bacteria is very rapid in fruits that are less acidic, such as melons. However, thanks to the strain of the present invention, the growth of these pathogens may be controlled in a wide range of fruits.
As discussed in the description of the invention, one objective of the present invention is to provide a method for preparing fruit which comprises the step of applying a preparation that comprises the biological culture of the new strain CBS136973 to the fruit.
According to a preferred embodiment of said method, the fruit is cut in pieces prior to applying said preparation.
Preferably, the concentration of strain CBS136973 in said preparation is equal to or greater than the estimated pathogen concentration that the fruit, preferably the fresh-cut fruit, may contain.
According to one embodiment, the concentration of said strain in the preparation is equal to or greater than 10 5 cfu/ml.
It has been observed that this concentration is effective against any of the three microorganisms Salmonella spp., Listeria spp. and/or Escherichia coli O157:H7, and at much higher concentrations than those whereat said microorganisms may be found in fresh-cut fruit in real conditions.
Advantageously, the concentration of said strain in the preparation is equal to or greater than 10 7 cfu/ml.
It has been observed that this concentration guarantees a reduction in the pathogenic bacteria of at least two logarithmic units (two units of the base-10 logarithmic scale), regardless of the concentration of pathogenic bacteria in the fruit.
According to another embodiment, the method comprises the step of packaging the fruit once said preparation has been applied.
Advantageously, said method further comprises the step of providing a modified atmosphere to the fruit and/or the step of providing a refrigeration temperature to the fruit, for example, a temperature equal to or lower than 10° C., preferably a temperature equal to or lower than 5° C.
The modified atmosphere may be provided in a passive manner, for example, by packaging the product using plastic films with different permeabilities to gases, passively creating a favourable modified atmosphere as a result of the permeability of the container wall and factors such as respiration of the product and biochemical changes.
Packing the product in a modified atmosphere contributes to maintaining the freshness quality of the fresh-cut fruit for a longer period of time, which prolongs the shelf life of the product.
As previously discussed, the strain of the present invention is also effective under these conditions of packaging in a modified atmosphere.
Advantageously, said method for preparing the fruit, preferably fresh-cut fruit, comprises the step of applying an antioxidant to the fruit, prior to applying the suspension that contains the strain.
It has been observed that the strain of the present invention is not altered by the use of some antioxidant substances, for which reason said antioxidant substances may be used to delay oxidation of the fruit.
BRIEF DESCRIPTION OF THE FIGURES
In order to better understand what has been presented above, we attach some figures which represent, schematically and strictly for non-limiting purposes, the results of several embodiments.
In said drawings, the selected antagonists include those isolated from yeasts and bacteria such as CPA-1 ( Candida sake ), CPA-2 ( Pantoea spp.), PN5 ( Bacillus spp.), PN6 ( Pantoea spp.), CPA-5 ( Pseudomonas spp.), M174BAL2 ( Candida famata ), EL8 ( Pantoea spp.), 128-M ( Pantoea spp.), and C9P21 ( Pantoea spp.).
In said drawings,
FIG. 1 is a graphic representation that shows the population of Escherichia coli O157:H7 in apple cylinders after the inoculation (initial concentration), and after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include the antagonist CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 2 is a graphic representation that shows the population of Salmonella choleraesuis BAA-709 in apple cylinders after the inoculation (initial concentration), and after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 3 is a graphic representation that shows the population of Listeria innocua CECT-910 in apple cylinders after the inoculation (initial concentration), after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 4 is a graphic representation that shows the population of Escherichia coli O157:H7 in peach cylinders after the inoculation (initial concentration), after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 5 is a graphic representation that shows the population of Salmonella choleraesuis BAA-709 in peach cylinders after the inoculation (initial concentration), and after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 6 is a graphic representation that shows the population of Listeria innocua CECT-910 in peach cylinders after the inoculation (initial concentration), and after 2 days of incubation at 20° C. without an antagonist (control) and with 10 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 7 is a graphic representation that shows the population of Salmonella choleraesuis BAA-709 in melon cylinders after the inoculation (initial concentration) and after 2 days of incubation at 20° C. without an antagonist (control) and with 12 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 8 is a graphic representation that shows the population of Listeria monocytogenes LM230/3 in melon cylinders after the inoculation (initial concentration), and after 2 days of incubation at 20° C. without an antagonist (control) and with 12 of the selected antagonists, which include strain CBS136973. The values represent the mean of 6 values (2 assays with 3 repetitions each) and the bars represent the standard error. The numbers in brackets indicate the mean reduction obtained.
FIG. 9 is a graphic representation that shows of the population of Escherichia coli O157:H7 in apple cylinders coinoculated or not with a suspension of strain CBS136973 (10 8 cfu/ml) and stored at 5° C.
FIG. 10 is a graphic representation that shows the population of Escherichia coli O157:H7 in peach cylinders coinoculated or not with a suspension of strain CBS136973 (10 8 cfu/ml), and stored at 5° C. and at 10° C.
FIG. 11 is a graphic representation that shows the population of Salmonella choleraesuis BAA-709 in peach cylinders coinoculated or not with a suspension of strain CBS136973 (10 8 cfu/ml) and stored at 5° C.
FIG. 12 is a graphic representation that shows the population of Salmonella choleraesuis BAA-709 in melon cylinders coinoculated or not with a suspension of strain CBS136973 (10 8 cfu/ml), and stored at 5° C. and at 10° C.
FIG. 13 is a graphic representation that shows of the population of a cocktail of strains of Listeria monocytogenes (CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3) in melon cylinders coinoculated or not with strain CBS136973 at different concentrations and stored at 10° C.
FIG. 14 is a graphic representation that shows the population of a cocktail of strains of Salmonella choleraesuis (BAA-707, BAA-709, BAA-710 and BAA-711) in melon cylinders coinoculated or not with strain CBS136973 at different concentrations and stored at 10° C.
FIG. 15 is a graphic representation that shows of the population of a cocktail of strains of Salmonella choleraesuis (BAA-707, BAA-709, BAA-710 and BAA-711) in cut apple treated with antioxidant and inoculated or not with strain CBS136973 at 10 7 cfu/ml, by means of immersion for 2 min, and stored in modified atmosphere packaging (MAP) at 5° C. and 10° C.
FIG. 16 is a graphic representation that shows of the population of a cocktail of strains of Listeria monocytogenes (CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3) in cut apple treated with antioxidant and inoculated or not with strain CBS136973 at 10 7 cfu/ml, by means of immersion for 2 min, and stored in modified atmosphere packaging (MAP) at 5° C. and 10° C.
DESCRIPTION OF THE EXAMPLES
Below we present different assays, which must be interpreted to be an auxiliary tool for a better understanding of the invention and not as limitations to the object thereof.
The antagonistic effect was assayed in different strains of the genera Salmonella and Listeria , and in a strain of Escherichia coli O157:H7. These pathogens are the major ones in fruits and vegetables. Table 3, attached, shows the strains of foodborne pathogenic microorganisms used in the assays.
Firstly, we describe the examples performed in order to demonstrate the effectiveness under laboratory conditions. Secondly, we describe the examples performed to demonstrate the effectiveness under conditions that simulate commercial production.
Assays Designed to Demonstrate the Effectiveness of the Strain CBS136973 Against the Major Foodborne Pathogens in Fresh-Cut Fruit Under Laboratory Conditions
Below we describe a number of examples of assays performed under laboratory conditions which demonstrate the effectiveness of strain CBS136973 applied at different doses, in different fruits, at room temperature and under refrigeration conditions.
The strains of pathogenic microorganisms used in these assays were: Listeria innocua (CECT-910), Escherichia coli O157:H7 (NCTC-12900) and Salmonella choleraesuis (BAA-709, BAA-707, BAA-709, BAA-710 and BAA-711), and, in some cases, Listeria monocytogenes (CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3) (see Table 3).
The fruits were previously disinfected by means of spraying with 70% ethanol. Subsequently, cylindrical pieces of the fruit to be assayed were prepared, by means of a punch, with the dimensions of 1.2 cm in diameter and 1 cm in height, which is approximately equivalent to 1 g of fruit. These pieces were introduced into sterile test tubes and inoculated with 15 μl of a suspension that contained the two microorganisms (pathogen and antagonist), a process called coinoculation. In the control treatment, the pathogen was added to a tube with 10 ml of sterile water (without an antagonistic microorganism). Following the coinoculation, the fruit was allowed to dry at room temperature. Subsequently, 3 tubes were collected, and the initial pathogen concentration was measured by means of seeding in specific culture media. The other tubes were stored at 20° C., 10° C. or 5° C., depending on the assay. After 2 days (assays at 20° C.), or 2-3 days, 5-7 days and 10 days (assays at 5° C. or 10° C.), the pathogen concentration per piece of fruit was once again determined in the samples with an antagonist (treatment with an antagonist) and in those that did not have an antagonist (control treatment). The concentration data were transformed to Log 10 cfc.
In order to calculate the pathogen growth reduction value, the following formula was used:
Reduction Log 10 cfc=log 10 C t−control −log 10 C t+antagonist , where:
C t−control is the pathogen concentration in the control treatment after “t” days of storage, and C t+antagonist is the pathogen concentration in the treatment with an antagonist after “t” days of storage.
Positive reduction values indicate that the growth of the pathogen on the fruit assayed in the presence of the antagonist is lower than the same without an antagonist. The higher the value, the greater the effectiveness against the pathogen studied.
In the assays at room temperature (20° C.), in order to obtain the suspension of strain CBS136973 and the other strains assayed, production in NYDA medium incubated at 25° C. for 48 h was used. Isolated colonies were taken, suspended in sterile de-ionised water and, from said suspension, another suspension was prepared, which was adjusted, by means of a spectrophotometer, to different transmittances (λ=420 nm) that correspond to the different concentrations of antagonists assayed (10 5 cfu/ml, 10 6 cfu/ml, 10 7 cfu/ml and 10 8 cfu/ml).
In the assays under refrigeration conditions (5° C. or 10° C.), in order to obtain the suspension of strain CBS136973, production in a liquid medium was used. To this end, an Erlenmeyer flask was inoculated containing 50 mL of TSB and incubated at 30° C. for 20-24 h. It was centrifuged for 10 min at 10000 rpm and cells resuspended with 25 ml of sterile de-ionised water.
The pathogens were inoculated in tubes containing 10 ml of TSB medium ( Salmonella choleraesuis BAA-707, BAA-709, BAA-710 and BAA-711, and Escherichia coli O157:H7) or TYSEB medium ( Listeria innocua CECT-910 and Listeria monocytogenes CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3), which were incubated at 37° C. for 20-24 h. Subsequently, they were centrifuged at 8000 rpm for 10 min and cells resuspended with 5 ml of saline solution (0.85 g/l of NaCl). By measuring the transmittance at 420 nm and a curve previously obtained in the laboratory for each of the pathogens, the estimated pathogen concentration was determined.
TABLE 3
List of strains of foodborne pathogenic
microorganisms used in the assays.
Culture
Nomen-
collection
Species
Serovar
clature
ATCC
Salmonella choleraesuis subsp.
Agona
BAA-707
BAA-707
choleraesuis (Smith) Weldin
ATCC
Salmonella choleraesuis subsp.
Michigan
BAA-709
BAA-709
choleraesuis (Smith) Weldin
ATCC
Salmonella choleraesuis subsp.
Montevideo
BAA-710
BAA-710
choleraesuis (Smith) Weldin
ATCC
Salmonella choleraesuis subsp.
Gaminara
BAA-711
BAA-711
choleraesuis (Smith) Weldin
CECT-
Listeria monocytogenes
1a
CECT-
4031
(Murray et al. 1926 8 ) Pirie 1940
4031
CECT-
Listeria monocytogenes
4b
CECT-
4032
(Murray et al. 1926 8 ) Pirie 1940
4032
CECT-
Listeria monocytogenes
3a
CECT-
933
(Murray et al. 1926 8 ) Pirie 1940
933
CECT-
Listeria monocytogenes
4d
CECT-
940
(Murray et al. 1926 8 ) Pirie 1940
940
Listeria monocytogenes *
1/2a
LM230/3
CECT-
Listeria innocua
L. innocua
910
NCTC-
Escherichia coli (Migula)
E. coli
12900/
Castellani and Chalmers
O157:H7
ATCC
serotype O157:H7
700728
*Isolated from fresh-cut lettuce prepared at our laboratory (Abadias et al. 2008 5 )
CECT: Spanish Type Culture Collection; ATTC: American Type Culture Collection; NCTC: National Collection of Type Cultures
The pathogen concentrations assayed ranged between 10 5 cfu/ml and 10 7 cfu/ml. However, under real conditions, it is estimated that the 10 5 cfu/ml pathogen concentration, which in the assays performed corresponds to 10 3 cfu/g of product, is even a very high pathogen concentration (Salleh et al., 2003 6 ; Nguz et al., 2005 7 ); for this reason, the results obtained are presented under unfavourable/adverse conditions for strain CBS136973.
Example 1
Effectiveness of Strain CBS136973 Against Different Foodborne Pathogens on “Golden Delicious” Apples at 20° C.
FIGS. 1 to 3 show an example of the results obtained against strains of Escherichia coli O157:H7, Salmonella choleraesuis BAA-709 and Listeria innocua CECT-910, in “Golden Delicious” apples, comparing the effectiveness of strain CBS136973 with other strains isolated in the laboratory and which were assayed under the same conditions.
The suspension of strain CBS136973 was inoculated at approximately 10 8 cfu/ml and the pathogens at 10 7 cfu/ml. The pH of the apples was 3.8±0.2 and the acidity ranged between 1.6 and 2.9 g malic acid/l.
As shown in FIG. 1 , the initial concentration of E. coli O157:H7 was 5.1 log 10 cfu/g and it increased to 6.8 log 10 cfu/g in the control treatment (without an antagonist). On the contrary, in the pieces coinoculated with different antagonists, there was lower growth, with reductions between 1.0 and 1.6 log units. In the case of strain CBS136973, the pathogen population after two days of storage at 20° C. was even lower than the initial one (2.4 log 10 cfu/g), which indicates an effective reduction of 4.5 logarithmic units.
Similar results were obtained when the effectiveness of different strains was tested against Salmonella BAA-709 ( FIG. 2 ), with reductions ranging between 0.3 and 1.0 log units in the case of the other antagonists and of 4.7 log units in the case of the strain CBS136973.
The increase of Listeria innocua population on apples not treated with an antagonist after storage at 20° C. for 2 days was 2.5 log 10 cfu/g. In the case of some of the antagonists isolated in the laboratory, there was a significant reduction, between 1.1 and 2.2 log units, but strain CBS136973 showed much better results, with a reduction of 5.9 log units following the storage, which indicates that the population of Listeria innocua on apples that had been treated with strain CBS136973 was lower than 2 log 10 cfu/g ( FIG. 3 ).
Example 2
Effectiveness of Strain CBS136973 Against Different Foodborne Pathogens on Different Peach Varieties at 20° C.
FIGS. 4 to 6 show an example of the results obtained against strains of Escherichia coli O157:H7, Salmonella choleraesuis BAA-709 and Listeria innocua CECT-910, in peach, comparing the effectiveness of strain CBS136973 with other strains isolated in the laboratory and which were assayed under the same conditions.
Peaches of the “Merry O'Henry”, “Tardibelle”, “Roig d'Albesa”, “Placido”, “Royal Glory” and “Elegant Lady” varieties were used. The suspension of strain CBS136973 that was inoculated had a concentration of approximately 10 8 cfu/ml and the pathogens were inoculated at 10 7 cfu/ml. The pH of the peaches used was 3.6-5.3, and the acidity ranged between 2.8 and 7.8 g malic acid/l.
As shown in FIG. 4 , the initial concentration of E. coli O157:H7 on peach was 4.9 log 10 cfu/g, and after 2 days of storage at 20° C. it increased by approximately 3 log units in the pieces not treated with an antagonist. In the pieces inoculated with some of the isolated antagonists, the concentration of E. coli O157:H7 was reduced by between 1.8 and 3.0 log units, whereas the reduction with strain CBS136973 was 4.3 logarithmic units, the concentration at 2 days being even lower than the initial one, which demonstrates its great effectiveness.
FIG. 5 shows the results of the same assay, but performed with the strain of Salmonella BAA-709. In this case, the increase in the population after two days of storage at 20° C. was lower than that of E. coli O157:H7, an approximately 2.5 log increase. In general, the reductions with the other antagonists were lower, between 0.4 and 1.8 logarithmic units, but the reduction of Salmonella BAA-709 was greatest in those pieces of apple treated with strain CBS136973, 2.8 log units.
FIG. 6 shows the data relative to Listeria innocua on peach. In this FIG. 6 , we may observe that the population of Listeria innocua in the control treatment (without an antagonist) also increased by approximately 3 log units in each piece of peach, whereas in those pieces inoculated with different antagonists isolated in the laboratory the population was lower, with reductions between 0.7 and 2.1 log units being observed. Again, the reduction obtained with strain CBS136973 was greater, 4 logarithmic units, and, once again, the final population was even lower than the initial one.
Example 3
Effectiveness of Strain CPA-7 Against Different Foodborne Pathogens on Melon at 20° C.
FIGS. 7 and 8 show an example of the results obtained against strains of Salmonella choleraesuis BAA-709 and Listeria monocytogenes LM230/3, on melon, comparing the effectiveness of strain CBS136973 with other strains isolated in the laboratory and which were assayed under the same conditions.
Melon is a fruit that has a more neutral pH and less acidity than apple and peach (pH 5.7-6.5, acidity 0.7-1.9 g citric acid/l, generally). In this case, the problem of pathogens is more significant, because the pH does not act as a barrier to the growth of foodborne pathogens. The suspension of the strain CBS136973 was inoculated at approximately 10 8 cfu/ml and the pathogen was inoculated at 10 7 cfu/ml.
FIG. 7 shows the results for different strains of antagonistic microorganisms, including CBS136973, against Salmonella on pieces of “Toad Skin” melon. In this case, the reduction values ranged between 1.5 and 3.2 log units, the greatest reduction being obtained with strain CBS136973, a total of 3.5 log units. It may be observed that the growth of Salmonella on melon after 2 days of storage at 20° C. was very high in the control treatment (without an antagonist), 4.2 logarithmic units, with final population being greater than 10 8 cfu/g of product.
FIG. 8 shows the effectiveness of strain CBS136973 against the strain of Listeria monocytogenes LM230/3, in melon stored for 2 days at 20° C. As may be observed, in this case there is also a reduction in the pathogen with respect to the untreated control.
Example 4
Effectiveness of Strain CBS136973 Against Escherichia coli O157:H7 on “Golden Delicious” Apple Under Refrigeration Conditions
FIG. 9 shows the result of the effectiveness of strain CBS136973 against E. coli O157:H7 on “Golden Delicious” apple stored at 5° C. The assay was performed by the coinoculation of 15 μl of a suspension that contained both strains, E. coli O157:H7 at 10 7 cfu/ml and CBS136973 (30% transmittance, approximately 10 8 cfu/ml).
As may be seen in the figure, at 5° C. no growth of E. coli O157:H7 was observed on cut apple in the control treatment; on the contrary, in the samples coinoculated with the antagonist, there was a reduction from the second day of storage and, after 7 days, the population decreased to less than 10 cfu/g.
Example 5
Effectiveness of Strain CBS136973 Against Different Foodborne Pathogens on Peach Under Refrigeration Conditions
FIGS. 10 and 11 show the effectiveness of strain CBS136973 against Escherichia coli O157:H7 and Salmonella BAA-709 on peach (“Elegant Lady” and “Placido” varieties), at 5° C. and 10° C. The suspension that was inoculated had a concentration of strain CBS136973 of approximately 10 8 cfu/ml and 10 7 cfu/ml of pathogenic microorganisms.
As shown in FIG. 10 , strain CBS136973 reduces the pathogen concentration, the reduction being greater at 5° C. than at 10° C., and it is maintained even below the detection limit after 6 days of storage.
Similar results were obtained when strain CBS136973 was used against Salmonella on peach of the “Placido” variety ( FIG. 11 ). In this case, after 6 days of storage at 5° C., no Salmonella was detected in the pieces of cut peach, whereas the population was maintained in the treatment without an antagonist (control).
Example 6
Effectiveness of Strain CBS136973 Against Salmonella Choleraesuis BAA-709 on Melon Under Refrigeration Conditions
FIG. 12 shows the effectiveness of strain CBS136973 against Salmonella BAA-709 on melon stored at 10° C. The suspension that was inoculated had a concentration of strain CBS136973 of approximately 10 8 cfu/ml and 10 7 cfu/ml of pathogenic microorganisms.
As shown in the figure, at 10° C. the pathogen grew in the control treatment (without an antagonist), whereas in the treatment wherein CBS136973 was applied the population remained lower, with a reduction of more than 1.5 logarithmic units from the sixth day of storage. At 5° C., under the conditions assayed, Salmonella was not capable of growing and the addition of strain CBS136973 did not entail any changes with respect to the control treatment.
Example 7
Effectiveness of Strain CBS136973 Applied at Different Doses Against Different Foodborne Pathogens on Golden Delicious Apple at 20° C.
Tables 4, 5 and 6 show the effectiveness of strain CBS136973 applied at different doses, and against different concentrations of the pathogens Escherichia coli O157:H7, Salmonella choleraesuis BAA-709 and Listeria innocua CECT-910. This effectiveness was measured in Log 10 units of growth reduction in accordance with the formula cited above.
As may be observed in the attached tables, the results show a pathogen growth reduction for concentrations of strain CBS136973 equal to or greater than the inoculated pathogen concentration.
TABLE 4
Reduction values (Log 10 units) for Escherichia coli
O157:H7 applied at different concentrations, as a function
of the dose of strain CBS124167, on “Golden Delicious”
apple stored at 20° C. for 2 days.
Concentration of
Escherichia coli O157:H7
Dose strain CBS 124167
inoculated (cfu/ml)
(cfu/ml)
10 5
10 6
10 7
10 8
4.7
6.1
3.6
10 7
3.8
3.4
2.0
10 6
1.5
1.7
0.6
10 5
0.7
1.6
0.3
TABLE 5
Reduction values (Log 10 units) for Salmonella choleraesuis
BAA-709 applied at different concentrations, as a function
of the dose of strain CBS124167, on “Golden Delicious”
apple stored at 20° C. for 2 days.
Concentration of
Salmonella choleraesuis
BAA-709
Dose strain CBS124167
inoculated (cfu/ml)
(cfu/ml)
10 5
10 6
10 7
10 8
5.4
3.8
4.5
10 7
5.0
3.3
3.3
10 6
3.2
1.9
1.3
10 5
1.9
1.5
0.3
TABLE 6
Reduction values (Log 10 units) for Listeria innocua applied at
different concentrations, as a function of the dose of strain CBS124167,
on “Golden Delicious” apple stored at 20° C. for 2 days.
Concentration of
Listeria innocua
Dose CBS124167
inoculated (cfu/ml)
(cfu/ml)
10 5
10 6
10 7
10 8
5.0
4.5
3.5
10 7
4.2
3.9
2.2
10 6
3.1
2.1
1.1
10 5
2.2
1.3
0.8
In the case of Salmonella and Listeria innocua , inoculated in apple, the 1:1 (pathogen:antagonist) ratio is sufficient to observe reductions greater than 1.9 logarithmic units.
Of the doses assayed, the 10 8 cfu/ml dose is the one which shows the best results for the three pathogens (reductions greater than 3.5 logarithmic units). However, the 10 7 cfu/ml dose of strain CBS136973 is the one considered to be most adequate for commercial application, since it guarantees a minimum reduction of two logarithmic units for the three pathogens studied, regardless of the concentration of pathogenic bacteria on the fruit.
Example 8
Effectiveness of Strain CBS136973 Applied at Different Doses Against Different Foodborne Pathogens on Melon at 20° C. And 10° C.
In this example, a cocktail of strains of Salmonella choleraesuis (BAA-707, BAA-709, BAA-710 and BAA-711) or Listeria monocytogenes (CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3) was used.
Tables 7 and 8 show the effectiveness of strain CBS136973, applied at different doses, on melon stored at 20° C., against different concentrations of the cocktail of pathogens of the genera Salmonella and Listeria monocytogenes . This effectiveness was measured in Log 10 units of growth reduction in accordance with the formula cited above.
TABLE 7
Reduction values (Log 10 units) for Salmonella choleraesuis applied
at different concentrations, as a function of the dose of strain
CBS124167, on “Toad Skin” melon stored at 20° C. for 2 days.
Concentration of
Salmonella choleraesuis
Dose CBS124167
inoculated (cfu/ml)
(cfu/ml)
10 5
10 7
10 8
7.3
2.1
10 7
3.7
0.9
10 6
0.2
0.4
TABLE 8
Reduction values (Log 10 units) for Listeria monocytogenes applied
at different concentrations, as a function of the dose of strain
CBS124167, on “Toad Skin” melon stored at 20° C. for 2 days.
Concentration of
Listeria monocytogenes
Dose CBS124167
inoculated (cfu/ml)
(cfu/ml)
10 5
10 7
10 8
5.3
4.9
10 7
4.2
2.8
10 6
2.1
1.0
As may be seen in the tables, in melon, the 10 7 cfu/ml dose of strain CBS136973 shows growth reduction values of Salmonella and Listeria monocytogenes , applied at 10 5 cfu/ml of melon, which is approximately equivalent to 10 3 cfu/g melon, equal to or greater than 3.7 logarithmic units.
FIGS. 13 and 14 show the effectiveness of different concentrations of strain CBS136973 on melon stored at 10° C., against the aforementioned cocktails of Salmonella choleraesuis and Listeria monocytogenes applied at a concentration of 10 5 cfu/ml.
As shown in the figures, the reduction of Listeria monocytogenes and Salmonella is greater the higher the concentration of strain CBS136973.
Assay Designed to Demonstrate the Effectiveness of Antagonistic Strain CBS136973 Against the Major Foodborne Pathogens in Fresh-Cut Fruit Under Conditions that Simulate Commercial Production.
Below we describe an example of an assay on “Golden Delicious” apple under conditions that simulate commercial production.
In this example, a cocktail of strains of Salmonella choleraesuis (BAA-707, BAA-709, BAA-710 and BAA-711) and a cocktail of strains of Listeria monocytogenes (CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3) were used.
The whole apples were disinfected, the cores were removed and they were cut into ten slices. Subsequently, they were submerged in a bath containing the antioxidant NatureSeal® AS1 (6%, Agricoat Ltd., Great Shefford, UK), for 2 min, under stirring, and were allowed to dry.
Once they were treated with the antioxidant, the pieces of apple were submerged in a suspension that contained the cocktail of strains of the pathogen and the antagonist, for 1 min, under stirring, simulating the application that would take place in a fruit treatment line tank. In the control treatment, the pieces of apple were submerged in a suspension that contained the cocktail of strains of the pathogen without the antagonistic strain.
Subsequently, the pieces of apple were allowed to drain, packaged (200 g) in polypropylene containers with a 500-ml capacity and sealed with a polypropylene film of the type habitually used, with a thickness of 35 μm, a permeability to O 2 and CO 2 of 3500 cm 3 /m 2 *day*atm at 23° C., and a permeability to steam of 0.9 g/m 2 *day at 25° C. and 75% relative humidity. Due to respiration of the fruit and the permeability characteristics of the film to O 2 and CO 2 , a passive modified atmosphere (PMA) is created inside the container. Antagonistic strain CBS136973 may be affected by this atmosphere, for which reason its effectiveness must also be demonstrated under these modified atmosphere conditions.
The pieces of apples were stored at 5° C. and at 10° C. for 15 days (estimated shelf life for this type of products). Periodically, microbiological counts were performed and different quality parameters (colour, texture, pH, acidity, soluble solids content and visual quality) were determined.
In order to obtain the suspension of strain CBS136973, production in TSB liquid medium was used and the percent transmittance (λ=420 nm) was adjusted for a concentration of the strain of 10 7 cfu/ml.
The pathogens were inoculated in tubes containing 10 ml of TSB medium ( Salmonella choleraesuis BAA-707, BAA-709, BAA-710 and BAA-711) or TYSEB medium ( Listeria monocytogenes CECT-4031, CECT-4032, CECT-933, CECT-940 and LM230/3), which were incubated at 37° C. for 20-24 h. Subsequently, they were centrifuged at 8000 rpm for 10 min and the cellular precipitate was re-dissolved with 5 ml of saline solution (0.85 g/l of NaCl). By measuring the transmittance at 420 nm and a curve previously obtained in the laboratory for each of the pathogens, the estimated pathogen concentration was determined, which in the assay described was a suspension with a concentration of 10 5 cfu/ml.
Example 9
Effectiveness of Strain CBS136973 Against Different Foodborne Pathogens on “Golden Delicious” Cut Apple Packaged at Different Temperatures Under Conditions that Simulate Commercial Conditions
FIGS. 15 and 16 show the results obtained against the aforementioned cocktails of strains of Salmonella and Listeria monocytogenes , on “Golden Delicious” apple at 5° C. and 10° C.
The suspension that was inoculated by means of immersion of the pieces of apple contained a concentration of strain CBS136973 of 10 7 cfu/ml and a concentration of 10 5 cfu/ml of both pathogenic microorganisms.
As may be observed in the figures, strain CBS136973 was effective against Salmonella , especially at 10° C., where growth was observed. In the case of Listeria monocytogenes , growth reduction was observed at both 5° C. and 10° C.
Therefore, it may be concluded that strain CBS136973 is effective against different foodborne pathogens under conditions that simulate commercial conditions (refrigeration and passive modified atmosphere, PMA).
Moreover, it is worth noting that the application of strain CBS136973 did not affect the colour, or the texture, or the soluble solids or the acidity of the apples.
Although specific examples of the present invention have been described and represented, it is evident that a person skilled in the art may introduce variants and modifications, or replace the details with technically equivalent ones, without going beyond the scope of protection defined by the attached claims.
REFERENCES
(1) Behrendt, U., Ulrich, A., Schumann, P., Erler, W., Burghardt, J., Seyfarth, W. 1999. A taxonomic study of bacteria isolated from grasses: a proposed new species Pseudomonas graminis sp. nov. International Journal of Systematic Bacteriology 49: 297-308.
(2) Noval, C. 1991. Comprobación del poder patógeno. En: Manual de laboratorio. Diagnóstic® de hongos, bacterias y nematodos fitopatógenos. Ed. MAPA, pp. 137-148.
(3) Peix, A.; Rivas, R., Mateos, P. F., Martinez-Molina, E., Rodriguez-Barrueco, C., Velazquez, E. 2003. Pseudomonas rhizosphaerae sp. nov., a novel species that actively solubilizes phosphate in vitro. International Journal of Systematic and Evolutionary Microbiology, 53: 2067-2072.
(4) Peix, A., Rivas, R., Santa-Regina, I., Mateos, P. F., Martinez-Molina, E., Rodriguez-Barrueco, C., Velazquez, E. 2004. Pseudomonas lutea sp. nov., a novel phosphate-solubilizing bacterium isolated from the rhizosphere of grasses. International Journal of Systematic and Evolutionary Microbiology, 54: 847-850.
(5) Abadias, M., Usall, J., Anguera, M., Solsona, C., Viñas, I. 2008. Microbiological quality of fresh, minimally-processed fruit and vegetables, and sprouts from retail establishments. International Journal of Food Microbiology, 123: 121-129.
(6) Salleh, N. A.; Rusul, G., Hassan, Z., Reezal, A., Isa, S. H. Nishibuchi, M.; Radu, S. 2003. Incidence of Salmonella spp. in raw vegetables in Salangor, Malaysia. Food Control 14: 475-479.
(7) Nguz, K., Shindano, J., Samapundo, S., Huyghebaert, A. 2005. Microbiological evaluation of fresh-cut organic vegetables produced in Zambia. Food Control 16: 623-628.
(8) Murray, E. G. D., Webb, R. E., Swann, M. B. R. 1926. A disease of rabbits characterized by a large mononuclear leucocytosis, caused by a hitherto undescribed bacillus Bacterium monocytogenes (n. sp.). J. Pathol. Bacteriol. 29: 407-439.
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Substantially pure biological culture of a strain of the species Pseudomonas graminis , deposited with number CBS136973 at the depositary institution “Centraalbureau voor Schimmelcultures” (CBS) in Utrecht, Netherlands. Use of the CBS136973 culture as an antagonist for the biocontrol of foodborne pathogenic bacteria in fruit intended for human consumption. Method for treating the fruit which comprises the step of applying a preparation that comprises a culture of a strain of the species Pseudomonas graminis , deposited with number CBS136973 at the depositary institution “Centraalbureau voor Schimmelcultures” (CBS) in Utrecht, Netherlands, to the fruit. The application thereof makes it possible to reduce the growth of pathogens during the shelf life of the product, especially when the cold chain is broken.
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[0001] This patent application claims the benefit of U.S. Provisional Patent Application No. 60/806,534, filed Jul. 4, 2006
FIELD AND BACKGROUND OF THE INVENTION
[0002] The present invention relates to error correction of digital data and, more particularly, to a method of error correction for flash memory devices that store multiple bits per cell.
[0003] Flash memory devices have been known for many years. Typically, each cell within a flash memory stores one bit of information. Traditionally, the way to store a bit has been by supporting two states of the cell—one state represents a logical “0” and the other state represents a logical “1”. In a flash memory cell the two states are implemented by having a floating gate above the cell's channel (the area connecting the source and drain elements of the cell's transistor), and having two valid states for the amount of charge stored within this floating gate. Typically, one state is with zero charge in the floating gate and is the initial unwritten state of the cell after being erased (commonly defined to represent the “1” state) and another state is with some amount of negative charge in the floating gate (commonly defined to represent the “0” state). Having negative charge in the gate causes the threshold voltage of the cell's transistor (i.e. the voltage that has to be applied to the transistor's control gate in order to cause the transistor to conduct) to increase. Now it is possible to read the stored bit by checking the threshold voltage of the cell: if the threshold voltage is in the higher state then the bit value is “0” and if the threshold voltage is in the lower state then the bit value is “1”. Actually there is no need to accurately read the cell's threshold voltage. All that is needed is to correctly identify in which of the two states the cell is currently located. For that purpose it is enough to make a comparison against a reference voltage value that is in the middle between the two states, and thus to determine if the cell's threshold voltage is below or above this reference value.
[0004] FIG. 1A shows graphically how this works. Specifically, FIG. 1A shows the distribution of the threshold voltages of a large population of cells. Because the cells in a flash memory are not exactly identical in their characteristics and behavior (due, for example, to small variations in impurities concentrations or to defects in the silicon structure), applying the same programming operation to all the cells does not cause all of the cells to have exactly the same threshold voltage. (Note that, for historical reasons, writing data to a flash memory is commonly referred to as “programming” the flash memory.) Instead, the threshold voltage is distributed similar to the way shown in FIG. 1A . Cells storing a value of “1” typically have a negative threshold voltage, such that most of the cells have a threshold voltage close to the value shown by the left peak of FIG. 1A , with some smaller numbers of cells having lower or higher threshold voltages. Similarly, cells storing a value of “0” typically have a positive threshold voltage, such that most of the cells have a threshold voltage close to the value shown by the right peak of FIG. 1A , with some smaller numbers of cells having lower or higher threshold voltages.
[0005] In recent years a new kind of flash memory has appeared on the market, using a technique conventionally called “Multi Level Cells” or MLC for short. (This nomenclature is misleading, because the previous type of flash cells also have more than one level: they have two levels, as described above. Therefore, the two kinds of flash cells are referred to herein as “Single Bit Cells” (SBC) and “Multi-Bit Cells” (MBC).) The improvement brought by the MBC flash is the storing of two or more bits in each cell. In order for a single cell to store two bits of information the cell must be able to be in one of four different states. As the cell's “state” is represented by its threshold voltage, it is clear that a 2-bit MBC cell should support four different valid ranges for its threshold voltage. FIG. 1B shows the threshold voltage distribution for a typical 2-bit MBC cell. As expected, FIG. 1B has four peaks, each corresponding to one state. As for the SBC case, each state is actually a range and not a single number. When reading the cell's contents, all that must be guaranteed is that the range that the cell's threshold voltage is in is correctly identified. For a prior art example of an MBC flash memory see U.S. Pat. No. 5,434,825 to Harari.
[0006] Similarly, in order for a single cell to store three bits of information the cell must be able to be in one of eight different states. So a 3-bit MBC cell should support eight different valid ranges for its threshold voltage. FIG. 1C shows the threshold voltage distribution for a typical 3-bit MBC cell. As expected, FIG. 1C has eight peaks, each corresponding to one state. FIG. 1D shows the threshold voltage distribution for a 4-bit MBC cell, for which sixteen states, represented by sixteen threshold voltage ranges, are required.
[0007] When encoding two bits in an MBC cell via the four states, it is common to have the left-most state in FIG. 1B (typically having a negative threshold voltage) represent the case of both bits having a value of “1”. (In the discussion below the following notation is used—the two bits of a cell are called the “lower bit” and the “upper bit”. An explicit value of the bits is written in the form [“upper bit” “lower bit”], with the lower bit value on the right. So the case of the lower bit being “0” and the upper bit being “1” is written as “10”. One must understand that the selection of this terminology and notation is arbitrary, and other names and encodings are possible). Using this notation, the left-most state represents the case of “11”. The other three states are typically assigned by the following order from left to right: “10”, “00”, “01”. One can see an example of an implementation of an MBC NAND flash memory using this encoding in U.S. Pat. No. 6,522,580 to Chen, which patent is incorporated by reference for all purposes as if fully set forth herein. See in particular FIG. 8 of the Chen patent. U.S. Pat. No. 6,643,188 to Tanaka also shows a similar implementation of an MBC NAND flash memory, but see FIG. 7 there for a different assignment of the states to bit encodings: “11”, “10”, “01”, “00”. The Chen encoding is the one illustrated in FIG. 1B .
[0008] We extend the above terminology and notation to the cases of more than two bits per cell, as follows. The left-most unwritten state represents “all ones” (“1 . . . 1”), the string “1 . . . 10” represents the case of only the lowest bit of the cell being written to “0”, and the string “01 . . . 1” represents the case of only the most upper bit of the cell being written to “0”.
[0009] When reading an MBC cell's content, the range that the cell's threshold voltage is in must be identified correctly; only in this case this cannot always be achieved by comparing to only one reference voltage. Instead, several comparisons may be necessary. For example, in the case illustrated in FIG. 1B , to read the lower bit, the cell's threshold voltage first is compared to a reference comparison voltage V 1 and then, depending on the outcome of the comparison, to either a zero reference comparison voltage or a reference comparison voltage V 2 . Alternatively, the lower bit is read by unconditionally comparing the threshold voltage to both a zero reference voltage and a reference comparison voltage V 2 , again requiring two comparisons. For more than two bits per cell, even more comparisons might be required.
[0010] Denote a page in the flash memory as the smallest portion of data that can be separately written into the flash memory, then the bits of a single MBC cell may all belong to the same flash page, or these bits may be assigned to different pages so that, for example in a 4-bit per cell flash memory, the lowest bit is in page 0, the next bit is in page 1, the next bit in page 2, and the highest bit is in page 3.
[0011] MBC devices provide a significant cost advantage. An MBC device with two bits per cell requires about half the area of a silicon wafer required by an SBC of similar capacity. However, there are drawbacks to using MBC flash. Average read and write times of MBC memories are longer than of SBC memories, resulting in reduced performance. More importantly, the reliability of MBC is lower than SBC. The difference between the threshold voltage ranges in MBC are much smaller than in SBC. Thus, a disturbance in the threshold voltage (e.g. leakage of stored charge causing a threshold voltage drift or interference from operating neighboring cells), that are insignificant in SBC because of the large gap between the two states, may cause an MBC cell to move from one state to another, resulting in an erroneous bit. The end result is a lower performance specification of MBC cells in terms of data retention time or in terms of the endurance of the device to many write/erase cycles.
[0012] Flash memory cells, and especially flash memory cells of the NAND-type, have a non-zero probability of providing erroneous bits when read out. In other words—there is a non-zero (even though small) probability that when writing a specific bit of data into the flash memory device and later reading the bit out of the device, the read value of the bit will not be equal to the previously written value. This fact is typically explicitly stated in the datasheets of NAND-type flash memory devices, and the manufacturer usually provides a recommendation for the amount of error correction that should be applied to the data being read. For SBC flash memory devices it is typical for the manufacturer to recommend the use of an Error Correction Code (ECC) capable of correcting one bit error per each sector of 512 bytes of user data. For 2-bit-per-cell MBC flash memory devices it is typical for the manufacturer to recommend the use of an ECC capable of correcting four bit errors per each sector of 512 bytes of user data. This is in line with the previous observation that MBC cells are less reliable than SBC cells.
[0013] Error Correction Code implementations include two parts. The first part is called the “encoder” and is activated when writing the data into the memory. The encoder receives the user data as an input, and outputs a “codeword” that is a representation of the user data plus some extra information that will allow overcoming errors in the data should these errors occur. The second part is called the “decoder” and is activated when data are read from the flash memory device. The decoder receives the bits read out from the memory cells. Those bits should ideally be identical to the codeword previously stored, but in reality those bits might include erroneous bits. The decoder's task is then to use the extra information placed in the codeword by the encoder to recover the correct user bits.
[0014] ECC decoders can be classified into two types:
a. Iterative decoders b. Non-iterative decoders
[0017] For the purpose of the present invention, iterative decoders are defined as decoders that carry out a decoding algorithm in which a potential value of the decoded user data are generated by the algorithm and tested against a success criterion. If the success criterion is met, the potential value is made the decoded user data. If the success criterion is not met, the algorithm goes into another computation which results in a new potential value of the decoded user data, which in turn is tested against the success criterion according to the above decision logic. Non-iterative decoders are all decoders that are not iterative decoders. It should be noted that both iterative and non-iterative decoders may be implemented in hardware, in software, or in a combination of hardware and software, and all types of implementations are within the scope of the terms “iterative decoder” and “non-iterative decoder”.
[0018] Iterative decoders are typically more complex to implement than non-iterative decoders. On the other hand, the error correction capabilities of iterative decoders usually are superior to the error correction capabilities of non-iterative decoders.
[0019] As explained above, iterative decoders process information in iterations, using the output of one iteration as the input to the next iteration. To make this approach work an iterative code is typically constructed from simpler constituent codes. There are several families of codes that can be efficiently decoded by the iterative procedure. The most popular ones are Convolutional Turbo Codes (CTC), Turbo Product Codes (TPC), and Low Density Parity-Check (LDPC) codes. In CTC the constituent codes are convolutional codes, in TPC the constituent codes are simple block codes (e.g. parity-check, Hamming, two-error correcting BCH codes), and in LDPC codes the constituent codes are short parity-check and repetition codes.
[0020] For a survey of iterative schemes see S. Lin and D. J. Costello, Error Control Coding, Prentice-Hall, 2004.
[0021] Detailed description of CTC can be found in C. Berrou and A. Glavieux, “Near optimum error correcting coding and decoding: Turbo-codes”, IEEE Trans. Com., Vol. 44, N° 10, pp. 1261-1271, October 1996.
[0022] TPC codes are treated in R. M. Pyndiah, “Near-optimum decoding of product codes: Block turbo codes”, IEEE Trans. Com., vol. 46, pp. 1003-1010, August 1998.
[0023] LDPC codes are described in R. G. Gallager, “Low-density parity-check codes”, IRE Trans. Info. Theory, vol. IT-8, pp. 21-28, 1962.
[0024] At the present time, iterative decoding is used only in communication, and not in data storage applications. In particular, there are no flash memory systems that employ iterative decoders for correcting errors in data read from the flash memory. This is not surprising, given the relatively high implementation costs of iterative decoders.
[0025] As of the present time there are no commercially available MBC flash memory devices with more than two bits per cell. The major obstacle preventing such devices from becoming available is the poor reliability of the data read out of the cells of these memory devices. For example, with existing flash memory manufacturing technologies, MBC cells storing four bits per cell may output very unreliable data that requires an ECC capable of correcting hundreds of bit errors.
[0026] There is thus a need to find a way of making MBC flash memory devices with more than two bits per cell useful in spite of the large number of errors that these devices introduce into the data read out of them.
SUMMARY OF THE INVENTION
[0027] One conceptual innovation of the present invention is that, contrary to the conventional wisdom, iterative decoding is of practical use, not only in communication, but also in data storage. For example, iterative decoding of data stored in a flash memory device makes storing three or more bits per cell in the memory of such a device commercially viable.
[0028] Therefore, according to the present invention there is provided a method of processing a representation of a stored codeword, including the steps of: (a) reading the representation of the codeword from a memory wherein the stored codeword is stored; and (b) iteratively decoding a plurality of bits related to the representation of the stored codeword.
[0029] Furthermore, according to the present invention there is provided a controller, of a memory wherein is stored a representation of a codeword, the controller being operative to iteratively decode a plurality of bits related to the representation of the codeword.
[0030] Furthermore, according to the present invention there is provided a memory device including: (a) a memory for storing a representation of a codeword; and (b) a controller operative to iteratively decode a plurality of bits related to the representation of the codeword.
[0031] Furthermore, according to the present invention there is provided a system for storing data, including: (a) a memory device for storing the data as a representation of a codeword; and (b) a processor operative to iteratively decode a plurality of bits related to the representation of the codeword.
[0032] Furthermore, according to the present invention there is provided a method of processing data, including the steps of: (a) encoding the data as a codeword; (b) storing the codeword in a memory; (c) reading a representation of the codeword from the memory; and (d) iteratively decoding a plurality of bits related to the representation of the codeword.
[0033] According to a first basic method of the present invention, after a codeword is stored in a memory such as a flash memory, a representation of the stored codeword is read from the memory. What is read from the memory is only a “representation” of the stored codeword because errors in reading the stored codeword, or even instabilities of the memory that change bits of the stored codeword after the codeword has been stored, may cause some of the bits as read to be different from the bits of the codeword as originally stored. Then a plurality of bits related to the representation of the stored codeword is decoded iteratively. In the present context, “iterative decoding” means applying at least one iteration of an iterative decoding algorithm to some input.
[0034] The plurality of bits related to the representation of the stored codeword could be part or all of the stored codeword itself or could be part or all of the results of processing part or all of the stored codeword. For example, the plurality of bits related to the representation of the stored codeword could be the output of pre-processing part or all of the representation of the stored codeword, for example by applying a noniterative decoding algorithm to part or all of the representation of the stored codeword, in preparation for subsequent iterative decoding of that output.
[0035] Preferably, the memory is a flash memory.
[0036] Preferably, the decoding is effected only if the representation of the stored codeword is in error and the method includes the step of determining whether the representation of the stored codeword is in error. Most preferably, the determination of whether the representation of the stored codeword is in error is effected by steps including determining whether the representation of the stored codeword is a member of a set of codewords that includes the stored codeword. If the representation of the stored codeword is not included in that set, the representation of the stored codeword is deemed to be in error. The set of codewords may be either a set of systematic codewords or a set of nonsystematic codewords.
[0037] The iterative decoding may be effected using either a hard decoder or a soft decoder.
[0038] Preferably, the decoding is iterated until a predetermined criterion is satisfied. In one embodiment of the present invention, the predetermined criterion is a criterion that indicates success of the iterative decoding. Most preferably, such a criterion includes an output of the iterative decoding being a member of a set of codewords, either systematic codewords or nonsystematic codewords, that includes the stored codeword. Another, less preferable criterion for success includes the output of an iterative decoding iteration being identical to the input to that iteration. Alternatively, the predetermined criterion is a criterion that indicates failure of the iterative decoding. Most preferably, such a criterion includes a maximum number of iterations of the iterative decoding algorithm.
[0039] According to a second basic method of the present invention, data are encoded as a codeword. The codeword is stored in a memory. A representation of the codeword is read from the memory. Then, a plurality of bits related to the representation of the codeword is decoded iteratively. The plurality of bits related to the representation of the stored codeword could be part or all of the stored codeword itself or could be part or all of the results of processing part or all of the stored codeword.
[0040] Preferably, the memory is a flash memory. The encoding of the data may be either systematic encoding or nonsystematic encoding.
[0041] The scope of the present invention also includes a controller, of a memory wherein is stored a representation of a codeword, that recovers the codeword using the first method of the present invention, a memory device that includes a memory for storing a representation of a codeword and a controller of the present invention, and a system for storing data that includes a memory device for storing the data as a representation of the codeword and a processor that recovers the data using the first method of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
[0043] FIGS. 1A-1D show threshold voltage distributions in a one-bit flash cell, a two-bit flash cell, a three-bit flash cell and a four-bit flash cell;
[0044] FIG. 2 is a high-level block diagram of a flash memory device of the present invention;
[0045] FIG. 3 is a high-level partial block diagram of a data storage system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0046] The principles and operation of a flash memory decoder according to the present invention may be better understood with reference to the drawings and the accompanying description.
[0047] The present invention uses iterative decoders in the ECC employed in flash memory storage systems that use MBC flash memory devices. The method of the present invention operates as follows:
a. User data are provided by an external host computer to a flash memory storage system of the present invention in order to be stored for later recall. b. The encoder part of an ECC module of the storage system encodes the user data into a codeword that is a representation of the user data plus some extra information that allows overcoming errors in the data should such errors occur. Typically the stored codeword includes the original user data bits plus some parity bits that are computed based on the user data bits. The encoding may be done using any ECC algorithm known in the art, as long as there is a corresponding iterative decoding algorithm capable of decoding the codeword. c. The codeword is stored into the memory device. d. The host computer requests the retrieval of the user data. e. The codeword bits are read out of the storage cells, potentially with errors in some of the bits compared to the originally stored bits. The read bits include bits corresponding to both the user data bits and the parity bits. f. The decoder part of the ECC module of the storage system decodes the read bits using an iterative decoding algorithm. When eventually the success criterion of the iterative decoder is met, the last potential value of the user data (which was produced in the last iteration and for which the criterion is met) is declared as the decoded user data. The decoding may be done using any iterative decoding algorithm known in the art, as long as that iterative decoding algorithm matches the encoding algorithm used for generating the codeword. g. The decoded user data are returned to the host computer. h. If in step “f” the success criterion is not met until a failure criterion is met, the decoding is considered to have failed. The failure criterion may be a limit on the number of decoding iterations or it may be a limit on the decoding time, or some other criterion. In case of decoding failure the designer may choose between returning an error indication to the host computer or returning incorrect data to the host computer without providing an error indication. If the ECC algorithm is appropriately chosen for the reliability characteristics of the flash media, such decoding failure will be extremely rare and can be ignored.
[0056] It should be noted that the number of iterations executed by the decoder is not fixed and may depend both on the number of errors and the specific value of the user data. For example, one invocation of the iterative decoder may execute only two iterations before meeting the success criterion and converging to the correct decoded data, while another invocation of the same decoder may execute fifteen iterations for producing the same results, even though the decoded user data are the same in both invocations. This might happen if the first invocation had to deal with a small number of errors while the second invocation had to deal with a large number of errors. But, even with an equal number of errors in two invocations of the decoder, the number of iterations need not be the same if the user data are not the same.
[0057] It should also be noted that the iterative decoder may stop after only a single iteration or even after no iterations at all. For example, the codeword typically is a member of a set of allowed codewords. If the read bits correspond to a member of this set, it is assumed that the read bits were originally encoded as the codeword to which the read bits correspond, and no further decoding is needed. This is the usual case in which the input to the decoder has no errors at all, in which case the success criterion is met without a need for any other computation except the testing of the success criterion. In practice, the number of allowed codewords almost always is far too large for the read bits to be compared directly to the set of allowed codewords to determine whether the read bits belong to that set. Instead, it is checked whether the read bits satisfy a certain mathematical condition that is equivalent to membership in the set. Fir example, if the code used is a linear code, a necessary and sufficient condition for a column vector d of read bits to be a codeword is that d satisfy an equation of the form Hd=0, where H is a constant matrix that depends on the code used, 0 is a column vector of zeros, and the “additions” in the matrix-vector multiplication are XOR operations. The same holds, in case the read bits do not correspond to a member of the set of allowed codewords, for determining whether the output of each iteration is a member of the set. Satisfaction of the condition that the output of an iteration is a member of the set is the criterion for success.
[0058] Another criterion for nominal success is that the current iteration does not change its input. This is a less preferable criterion than the output of an iteration being a member of a set of allowed codewords, because all that no change to the input means, for some iterative decoding algorithms, is that there may be no point in continuing to apply the present decoding algorithm.
[0059] It should further be noted that even though in the example described above the iterative decoding decodes the complete codeword in a single decoding run, the present invention also includes within its scope decoder implementations in which an iterative decoding is activated on one or more portions of the read bits, and additional logic is then applied for combining results of the one or more activations of iterative decoding into the final decoded user data, possibly also combining results of portions of the codeword decoded by non-iterative methods. The innovation of the present invention lies in the use of an iterative decoder as part of reading data from flash memory storage systems, regardless of whether additional methods are also used and combined for generating the final decoded user data.
[0060] It should further be noted that the recovering of the user data from the codeword may rely on additional inputs beyond the read bits themselves, such as error probabilities, error distributions or other information, whether pre-defined or determined at decoding execution time. See, for example, U.S. patent application Ser. No. 11/339,571, to Litsyn et al., which is incorporated by reference for all purposes as if fully set forth herein. The present invention is applicable in the context of either “hard” decoders, that operate on just the read bits themselves, or “soft” decoders, that operate on both the read bits and estimates of the probabilities of these bits being in error. The innovation of the present invention lies in the use of an iterative decoder as part of reading data from flash memory storage systems, regardless of whether additional inputs beyond the read bits are also used for generating the decoded user data.
[0061] By using iterative decoding, the ECC can cost-effectively correct a higher number of errors in the data than is typically possible with non-iterative decoders for a similar level of output reliability. Even though the complexity of the iterative decoder might be higher than the complexity of a non-iterative decoder, this added cost easily pays itself back by enabling the use of MBC flash memory systems with a large number of bits per cell. Such MBC systems that store three or four or even higher number of bits per cell provide for a lower cost per bit than either SBC or two-bits-per-cell MBC storage systems, and this cost reduction easily outweighs the extra cost of the iterative decoder.
[0062] So far, the present invention has been presented in the context of error correction schemes that are “systematic”. In systematic error correction coding, the original data bits are preserved by the encoding process and can be identified within the bits stored. In other words, the error correction mechanism takes the original data bits, appends to these bits some parity bits, and stores both data bits and parity bits. Later, when reading the stored bits, both the data bits and the parity bits are read, and the parity bits enable the correction of errors in the read data bits, thus regenerating the original data bits.
[0063] However, the present invention is equally applicable to non-systematic error correction codes. In such codes the original data bits are not preserved and are not stored. Instead, the encoding process transforms the original data bits into a larger group of bits that are the bits actually stored (herein called “the protected data bits”). When reading the stored protected data bits the original data bits are re-generated, even if there are errors in the protected data bits. The defining characteristic of non-systematic codes is that there is no direct correspondence between a specific original data bit and a specific stored bit. An original data bit is “scattered” in multiple stored bits, and only the combination of those multiple stored bits reveals the value of the original bit.
[0064] Referring again to the drawings, FIG. 2 is a high-level block diagram of a flash memory device 20 of the present invention, coupled to a host 30 . FIG. 2 is adapted from FIG. 1 of Ban, U.S. Pat. No. 5,404,485, which patent is incorporated by reference for all purposes as if fully set forth herein. Flash memory device 20 includes a flash memory 24 , a controller 22 and a random access memory (RAM) 26 . Controller 22 , that corresponds to “flash control 14” of U.S. Pat. No. 5,404,485, manages flash memory 24 , with the help of RAM 26 , as described in U.S. Pat. No. 5,404,485. Flash memory 24 encodes data, two or more bits per cell of flash memory 24 , as described in U.S. Pat. No. 6,522,580 or in U.S. Pat. No. 6,643,188, either as a systematic codeword or as a nonsystematic codeword. When reading the data, controller 22 applies error correction as described above.
[0065] FIG. 3 is a high-level partial block diagram of an alternative data storage system 50 of the present invention. Data storage system 50 includes a processor 52 and four memory devices: a RAM 54 , a boot ROM 56 , a mass storage device (hard disk) 58 and a flash memory device 40 , all communicating via a common bus 60 . Like flash memory device 20 , flash memory device 40 includes a flash memory 42 . Unlike flash memory device 20 , flash memory device 40 lacks its own controller and RAM. Instead, processor 52 emulates controller 22 by executing a software driver that implements the methodology of U.S. Pat. No. 5,404,485 in the manner e.g. of the TrueFFS™ driver of M-Systems Flash Disk Pioneers Ltd. of Kfar Saba, Israel. Flash memory 42 encodes data, two or more bits per cell of flash memory 42 , as described in U.S. Pat. No. 6,522,580 or in U.S. Pat. No. 6,643,188, either as a systematic codeword or as a nonsystematic codeword. When reading the data, processor 52 applies error correction as described above. Flash memory device 40 also includes a bus interface 44 to enable processor 52 to communicate with flash memory 42 .
[0066] The code of the software driver that processor 52 executes to manage flash memory 42 is stored in mass storage device 58 and is transferred to RAM 54 for execution. Mass storage device 58 thus is an example of a computer-readable code storage medium in which is embedded computer readable code for managing flash memory 42 according to the principles of the present invention.
[0067] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. The scope of the present invention includes methods for reading data bits from an MBC flash memory device, as described above The scope of the present invention also includes a controller, for a MBC memory, that recovers data stored in the memory using one of the methods of the present invention, a memory device that includes a MBC memory and a controller of the present invention, and a computer-readable storage medium having embodied thereon computer-readable code for managing a memory according to one of the methods of the present invention.
[0068] Furthermore, even though the primary intended application of the present invention is to MBC flash memories, it will be appreciate that the present invention also is applicable to SBC flash memories, or indeed to memories generally, whether based on flash technology or some other technology, and whether non-volatile or volatile.
[0069] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made.
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Data are encoded as a systematic or nonsystematic codeword that is stored in a memory such as a flash memory. A representation of the codeword is read from the memory. A plurality of bits related to the representation of the codeword is decoded iteratively. The plurality of bits could be, for example, part or all of the representation of the codeword itself or part or all of the results of preliminary processing of part or all of the representation of the codeword.
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FIELD OF THE INVENTION
The invention relates to an examination apparatus and a method for the study of dynamic processes in a body volume, particularly of perfusion, as well as a record carrier with software for the execution of said method.
BACKGROUND OF THE INVENTION
The study of perfusion processes in the body volume of a patient is necessary for the diagnosis of cardiovascular diseases. Such perfusion studies typically involve the injection of a bolus of a contrast agent via a catheter or intravenously and the generation of a sequence of X-ray projections that show the spreading of said bolus in the vessel system and the surrounding tissue. In complex vessel trees like the cerebral vessel tree, it may however be difficult to judge the observed process based on two-dimensional projections acquired in the angio-suite. This is especially true for brain perfusion, where three-dimensional tomographic images of excellent contrast resolution are required for a careful diagnosis.
SUMMARY OF THE INVENTION
Therefore, it was an object of the present invention to provide means for a more versatile study of dynamic processes, particularly of perfusion in a complex vessel system and the surrounding tissue.
This object is achieved by an examination apparatus according to claim 1 , by a method according to claim 9 , and by a record carrier according to claim 10 . Preferred embodiments are disclosed in the dependent claims.
The examination apparatus according to the present invention may be used for the study of dynamic processes in a body volume. A very important (but not limiting) example that will be in the focus of the following description is the study of perfusion in the vessel system of a patient. The examination apparatus comprises an X-ray device with an X-ray source and an X-ray detector that can be moved relative to an object and a data processing system (computer) that is coupled to the X-ray device in order to control it and to evaluate the generated image data. The examination apparatus is adapted to execute the following steps:
a) The generation of a series of X-ray projections of the body volume along a trajectory during a given duration, said generation being achieved by the X-ray device under the control of the data processing system. A “projection series along a trajectory” means that the projection directions with which a certain point of a body volume is mapped intersect both said point and the trajectory. Such projections may be achieved if the X-ray source moves along said trajectory while emitting X-rays towards the body volume. b) The reconstruction of a temporal sequence of three-dimensional (3D) images of the body volume, wherein the reconstruction of each 3D image is based on a subset of projections from said series of X-ray projections that were generated during a connected temporal window within the aforementioned duration. Furthermore, the temporal windows are chosen such that they overlap, or, more precisely, that for each temporal window there is at least one other temporal window which partially overlaps with it. The temporal windows may for example have the same size and may be shifted with respect to each other by a small percentage of that size.
The examination apparatus allows the study of dynamic processes like perfusion in complex spatial environments, for example the brain of a patient, because the process is visualized in three-dimensional images. The reconstruction of such 3D images is possible due to the application of trajectories for the X-ray device which allow a continuous movement of the device and the acquisition of enough different projections for three-dimensional (exact) reconstruction methods. Moreover, the evaluation of the series of projections in overlapping temporal windows provides the high temporal resolution which is needed for the observation of the underlying processes and which makes optimal use of the available data. The evaluation of a series of images of a dynamic process in overlapping temporal windows is known as “sliding window approach” from the literature (d'Arcy J A; Collins D J; Rowland I J; Padhani A R; Leach M O: “Applications of sliding window reconstruction with Cartesian sampling for dynamic contrast enhanced MRI”, NMR in Biomedicine, vol. 15, no. 2, pp. 174-183, April 2002).
The examination apparatus may further comprise an injection device for the controlled injection of a contrast agent into the vessel system of patient. The injection device may be adapted to be manually controlled by the medical staff. Alternatively, said injection device may be coupled to and controlled by the data processing system. The use of controlled injections makes the examination apparatus suited for perfusion studies in a patient.
The X-ray device preferably comprises an X-ray source and a detector that are rigidly coupled to each other, for example via a C-arm, and that can be moved commonly on the surface of a sphere or a part of such a surface. In this case projections of a body volume located at the centre of said sphere can be produced from different directions, thus providing the necessary data for exact three-dimensional reconstruction methods.
According to another preferred embodiment of the invention, the trajectory is closed. In this case the X-ray device can repeatedly move along the trajectory while generating projections from identical or similar directions at different times.
The trajectory may be planar, for example an arc along which the X-ray device sweeps continuously back and forth. The trajectory may also be non-planar and preferably of a form that allows the application of exact reconstruction algorithms. A non-planar trajectory may particularly be produced by the superposition of oscillations in azimuthal and polar directions.
Each subset of projections that belong to a certain temporal window and that are used for the reconstruction of a 3D image is preferably just so large that the application of an exact reconstruction method is possible. Then 3D images with high contrast and accuracy can be achieved, while the restriction to a minimal subset of this kind guarantees are good correlation of the 3D image with the situation in the time point that corresponds to the temporal window.
While exact reconstruction methods for the generation of the 3D images are preferred due to their higher accuracy, approximation methods may of course be used, too. Moreover, the reconstruction of the 3D images may be achieved by direct inversion methods or by iterative reconstruction methods which are known to a person skilled in the art.
The projections within a subset or temporal window that are used for the reconstruction of a certain 3D image originate from different time points and therefore represent the observed body volume in different states of the dynamic process. If the temporal window is small compared with the time scale of the dynamic process, the changes of the process during the temporal window may be neglected and the 3D image that is reconstructed from the temporal window may be associated with a certain reference time point, for example the midpoint of the temporal window. According to a further development of the invention, the projections of a subset are applied in the reconstruction method with a weighting factor that corresponds to their temporal distance to said reference time point. Projections that are temporally close to the reference time point are then given a higher weight in the reconstruction than projections far away from said reference time point, because the latter may show the dynamic process in a state that has changed significantly with respect to the reference time point.
The reconstruction method for the 3D images may make use of redundancy compensation functions. In this case the difference of such a redundancy compensation function for two trajectory sections that belong to consecutive subsets is preferably used to update the corresponding 3D images.
The invention further comprises a method for the study of dynamic processes in a body volume, which comprises the following steps:
a) Generating during a given duration a series of X-ray projections of the body volume along a (planar or preferably non-planar) trajectory. b) Reconstructing a temporal sequence of 3D images of the body volume, wherein each 3D image is based on a subset of projections from said series, the subset belonging to a temporal window within said duration, and wherein said temporal windows overlap.
The method comprises in general form the steps that can be executed with an examination apparatus of the kind described above. Therefore, reference is made to the preceding description for more information on the details, advantages and improvements of that method.
Furthermore, the invention comprises a record carrier, for example a floppy disk, a hard disk, or a compact disc (CD), on which a computer program for the study of dynamic processes in a body volume is stored, said program being adapted to execute the aforementioned method.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following the invention is described by way of example with the help of the accompanying drawings in which:
FIG. 1 is a diagrammatic representation of an examination apparatus according to the present invention;
FIG. 2 shows an exemplary closed, non-planar trajectory in a perspective view and in three orthogonal projections;
FIG. 3 illustrates the temporal overlapping of subsets of projections that are used for the 3D reconstruction.
DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 is a principle sketch of an examination apparatus according to the present invention that may be used for perfusion studies in a patient 1 . The apparatus comprises a rotational X-ray device 10 which is in the shown example a conventional system with an X-ray source 11 and an X-ray detector 13 that are rigidly connected via a C-arm 12 . The X-ray device can be rotated around a point in space such that the X-ray source 11 and the detector 13 move on the surface of a sphere (or at least part thereof) and always face each other diametrically. Thus projections of a body volume in the centre of the sphere, for example of the brain or the heart of a patient 1 , can be generated from different directions.
FIG. 2 shows in a perspective and in projections a typical closed, non-planar trajectory T that can be followed by the X-ray source 11 and the detector 13 , respectively, during a typical movement of the X-ray device 10 . The whole trajectory T lies in the surface of a sphere (not shown) with the centre C. Each point of the trajectory T may the described in spherical coordinates (with the centre C as origin) by a polar angle φ and an azimuthal angle θ. The temporal course of said angles during the movement of the X-ray device 10 on the trajectory T is principally shown in the upper two diagrams of FIG. 3 . If the amplitude of the oscillation in θ is zero, a planar trajectory results that corresponds to an arc of a circle (extending over 180° plus the fan angle of the beam) and along which the X-ray device 10 repeatedly sweeps back and forth.
Other examples of suited closed, non-planar trajectories may be found in the article “Complete Source Trajectories for C-Arm Systems and a Method for Coping with Truncated Cone-Beam Projections” (H. Schomberg in: 3D-2001—The Sixth International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine, pp. 221-224), which is incorporated into the present application by reference.
FIG. 1 further shows a data processing system 30 that comprises a computer 32 to which a monitor 31 and an input device like a keyboard 33 are connected. The computer 32 is further connected to the X-ray device 10 in order to control the exposures and to evaluate the generated projections. The computer 32 comprises typical components like central processing unit, memory, I/O interfaces and the like together with appropriate software in order to fulfill the functions that are described in more detail below. The computer 32 may particularly reconstruct 3D images of the target area of the patient 1 from projections from different directions generated by the X-ray device 10 . These 3D images may then be displayed on a monitor 31 for a user.
Moreover, FIG. 1 depicts an injection device 20 by which for example a contrast agent can be injected into the vessel system of the patient 1 in a controlled way. Typically, the injection system comprises a motor driven syringe with contrast agent, and a catheter that runs from the syringe into the body of the patient, ending at the region of interest in the vessel system. The injection device 20 may be manually controlled or be coupled to the computer 32 such that it can be controlled by the computer and/or that it can transmit data about its function to the computer.
In order to study a dynamic process like perfusion in the vessel system of the patient 1 , the described examination apparatus will be used in a way which leads to 3D volume information of adequate temporal resolution by utilizing exact reconstruction methods for planar or non-planar source orbits combined with sliding window reconstruction principles. It is suggested to use a closed, non-planar acquisition trajectory T like that in FIG. 2 for perfusion imaging. Cone beam projection data are acquired for the time interval [0, D], in which the perfusion process takes place, by covering the closed trajectory T for multiple times using a continuous system movement. The sampling of the projection acquisition may be constant or variable in time. The acquisition takes place at the maximum system speed to guarantee high temporal resolution.
The full series of generated projections covering the trajectory T for multiple times is marked by Λ in FIG. 3 (wherein each dot represents one projection). It may be subdivided into overlapping subsets Λ i each of which corresponds to a certain temporal window and which are preferably large enough to enable exact reconstruction of the volume of interest. These subsets/temporal windows are chosen with equal or variable spacing in the temporal domain.
To each subset Λ i of the series Λ an exact reconstruction method is applied, for example the method described by Defrise and Clack (M. Defrise, R. Clack: “A cone-beam reconstruction algorithm using shift-invariant filtering and cone-beam back projection”, IEEE Trans. Med. Imag., vol. 13, no. 1, pp. 186-195, March 1994), taking the redundancy of the 3D Radon data into account in a correct manner. If for example the trajectory of the X-ray source is parameterized by a parameter λ, each source position for projection acquisition can be described by a vector ζ (λ). A Radon plane measured from such a source position is then characterized by its normal vector ξ, i.e. all vectors x lying in that plane fulfill (x−ζ(λ))·ξ=0. With ρ=ζ(λ)·ξ, a Radon value is generated at R f(ρξ, λ), wherein R f is the Radon transform of a function f. One Radon value can be generated by more than one source position λ. Since exact reconstruction requires complete sampling of the Radon space and correct handling of the redundancies, a redundancy compensation function is introduced into the back projection formula according to
M i ( ξ , λ ) = 1 n i ( ξ , λ ) , ( 1 )
where n i (ξ, λ) means that a specific Radon value can be delivered several times by a set of projections Λ i . For practical reasons allowing discrete implementation a differentiable and normalized version of M i (ξ, λ) is used in the back projection expression.
From the complete series Λ of available projections (multiple covered trajectory) the subset Λ i (centered at a reference time point t i ) which enables exact reconstruction of the volume of interest can now be selected by an appropriate redundancy compensation function M i (ξ, λ). For optimal computational performance, the difference of the redundancy compensation function of two trajectory intervals may be used to update the reconstructed volume originating from the trajectory part Λ i+1 with respect to the volume result from Λ i . Using this acquisition approach, the exact reconstruction of the same volume at multiple time steps t i with a temporal resolution Δt i is feasible.
Any other suitable exact or approximate reconstruction method may also be used, which is capable to process projection data acquired along non-planar orbits and to deliver excellent contrast resolution. Apart from direct inversion schemes, also iterative reconstruction methods may be applied.
Temporal resolution can be improved using varying temporal gating functions that weight projections near the reference time point ti higher than those that are further away. The result of this sliding window 3D reconstruction can be used as input for 3D perfusion analysis of a target structure.
Finally it is pointed out that in the present application the term “comprising” does not exclude other elements or steps, that “a” or “an” does not exclude a plurality, and that a single processor or other unit may fulfill the functions of several means. Moreover, reference signs in the claims shall not be construed as limiting their scope.
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The invention relates to an examination apparatus and a method for perfusion studies in a patient ( 1 ). According to the method, a rotational X-ray device ( 10 ) is moved on a closed, preferably non-planar trajectory (T) while continuously generating projections of the patient ( 1 ) after the injection of a contrast agent with an injection device ( 20 ). The projections are used by a data processing system ( 30 ) in a sliding window technique to reconstruct three-dimensional images of the body volume. The resulting sequence of 3D images may be displayed on a monitor ( 31 ) to reveal the desired information about the perfusion process.
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BACKGROUND
1. Technical Field
The present disclosure relates to vehicle control systems that enhance vehicle stability and performance.
2. Background Art
Stability-control systems are increasingly being used in automotive vehicles. In some prior two driven axle systems, a mechanical coupling is provided between the front and rear axles of the vehicle. In the event that one or both of the tires associated with the primary driven axle lose traction, the coupling apparatus, which is normally uncoupled, is commanded to couple the two axles so that torque is redistributed between a primary axle and a secondary axle. Although such a mechanical system provides improved performance compared to a purely braking approach such as with anti-lock braking systems, a mechanical system has several disadvantages. There is a delay between the time that the traction loss is detected and the mechanical coupler actually redistributes torque from the slipping tires of the primary axle to the wheels of the secondary. In situations such as encountering a patch of ice, in which road surface conditions can change very rapidly, a mechanical system is incapable of effecting a change in torque distribution sufficiently fast. Furthermore, due to frictional losses and torque transfer capability through the mechanical coupler, the sum of the torques supplied to the two axles is somewhat less than what the powertrain supplies to the primary axle. Thus, when the mechanical coupler is invoked, there is a drop in longitudinal performance of the vehicle, which may be particularly noticeable during acceleration. The ability of a mechanical system to redistribute torque may be limited in torque and further hampered by environmental influences, such as temperature.
A shift in torque distribution is also found to be useful in understeer and oversteer cornering situations. A mechanical coupler can be used to couple the primary and secondary axles to redistribute the torque between the axles such that the unexpected vehicle understeer or oversteer tendency is compensated. However, as with the desire to redistribute torque for a forward traveling vehicle encountering insufficient or excessive turning moment, the mechanical coupler reacts more slowly than desired and the torque redistribution is less accurately controlled in the coupler such that the operator of the vehicle notices a uncomfortable change in vehicle turning property.
SUMMARY
To overcome at least one problem in the background art, a method to distribute propulsion to front and rear axles of a vehicle is disclosed, which includes estimating actual yaw rate, estimating desired yaw rate, and providing electrical energy to a front axle motor during oversteer. Oversteer is when actual yaw rate exceeds desired yaw rate by more than a first threshold yaw rate. In addition, electrical energy may be extracted from a motor coupled to the rear axle during oversteer. Or, in the event that the rear axle motor is providing torque to the rear axle, electric energy supplied to the rear axle motor is reduced. In one embodiment, electrical energy extracted from the rear axle motor is provided directly to the front axle motor.
During understeer, electrical energy is provided to the rear axle motor. Also, electrical energy is extracted from the front axle motor during understeer. Electrical energy extracted from the front axle motor can be provided directly to the rear axle motor. The electrical energy extracted from the motor coupled to the front axle and the energy supplied directly to the motor coupled to the rear axle are provided in such a way that a longitudinal velocity of the vehicle is largely unaffected or that desired by the operator of the vehicle. Understeer is when desired yaw rate exceeds actual yaw rate by more than a second threshold yaw rate. Actual yaw rate is estimated based on sensors coupled to the vehicle. Or, depending on the sensor set, actual yaw rate is measured directly. Desired yaw rate is based on a sensor coupled to a steering wheel of the vehicle.
A system to distribute propulsion in a vehicle is disclosed that includes: a first axle coupled to the vehicle, an internal combustion engine coupled to the first axle, a first axle motor coupled to the first axle, a second axle coupled to the vehicle, a second axle motor coupled to the second axle, and an electronic control unit (ECU) electronically coupled to the engine and the axle motors. The ECU commands the second axle motor to increase torque supplied to the second axle when the vehicle is moving in a direction in which the first axle leads and the vehicle is in an understeer situation. The ECU commands the first axle motor to decrease torque supplied to the first axle when the vehicle is moving in a direction in which the first axle leads and the vehicle is in the understeer situation. The decreased torque is a braking torque such that electrical energy is generated by the first axle motor. In one embodiment, the electrical energy generated by the first axle motor is supplied to the second axle motor.
The system may include a steering sensor coupled to a steering wheel, a vehicle speed sensor, and a yaw rate sensor coupled to the vehicle and electronically coupled to the ECU. The ECU, which is electronically coupled to the sensors, determines a desired yaw rate based on a signal from the steering sensor and the vehicle speed sensor. The ECU further determines an actual yaw rate based on a signal from the yaw rate sensor. Or, depending on the sensor set, the ECU may estimate the actual yaw rate based on other sensors. An understeer situation is based on the desired yaw rate exceeding the actual yaw rate by more than a first threshold and an oversteer situation is based on the actual yaw rate exceeding the desired yaw rate by more than a second threshold.
The ECU commands a front axle motor to increase torque supplied to the front axle and the rear axle motor to decrease torque supplied to the rear axle when the vehicle is in an oversteer situation. The ECU commands the rear axle motor to increase torque supplied to the rear axle and the front axle motor to decrease torque supplied to the front axle when the vehicle is in an understeer situation. If a motor is supplying a positive torque to the axle to which it is coupled, the torque can be decreased as desired down to zero, at which point further decreases in torque are provided by operating the motor as a generator.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic representation of a hybrid electric vehicle (HEV);
FIG. 2A shows a HEV on a desired turning path and oversteer and understeer paths;
FIG. 2B shows how torque increase to a front axle of a HEV affects yaw rate in an oversteer case;
FIG. 2C shows how torque increase to a rear axle of a HEV affects yaw rate in an understeer case;
FIG. 2D shows a vehicle indicating distances between the center of gravity and the axles;
FIG. 3 is a graph of the friction circle or the tire traction field; and
FIG. 4 is a flowchart of a method for redistributing torque between the axles according to an embodiment of the disclosure.
DETAILED DESCRIPTION
As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated and described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. Those of ordinary skill in the art may recognize similar applications or implementations consistent with the present disclosure, e.g., ones in which components are arranged in a slightly different order than shown in the embodiments in the Figures. Those of ordinary skill in the art will recognize that the teachings of the present disclosure may be applied to other applications or implementations.
In FIG. 1 , one embodiment of a hybrid electric vehicle (HEV) 10 is shown schematically. Rear wheels 12 are coupled via rear axle 16 with a rear axle motor 18 . Rear axle 16 has a differential 19 . Front wheels 14 are coupled to front axle 20 . A differential and final drive gear set 22 are coupled to front axle 20 . The vehicle powertrain system is coupled to differential 22 through a transmission 24 . Transmission 24 is coupled to a front axle motor 28 via a clutch 28 . Front axle motor 28 is coupled to an internal combustion engine 34 via a clutch 32 . Front axle motor 28 , in the arrangement shown in FIG. 1 , can be called an integrated starter generator (ISG) because it can be used to spin up engine 34 for starting purposes. Depending on the exact configuration, it is likely that all of the powertrain components cannot be coupled end to end within the width of HEV 10 . In the embodiment shown in FIG. 1 , a chain drive 30 is provided between engine 34 and front axle motor 28 such that engine 34 rotates along a first axis and front axle motor 28 and transmission 24 rotate along a second axis substantially parallel to the first axis. The configuration in FIG. 1 illustrates simply one HEV configuration. There are many alternatives for configuring HEV which do not depart from the scope of the present disclosure. HEV 10 shows an arrangement in which internal combustion engine 34 is coupled to the front wheels. In another embodiment, engine 34 is coupled to the rear axle. Front and rear axle motors 28 and 18 can operate as motors providing torque to the associated axle or as generators absorbing torque from the associated axle, i.e., providing a braking force on wheels associated with the axle.
Continuing to refer to FIG. 1 , wheels 12 and 14 are provided with traction sensors 36 , which are coupled to an ECU 38 . Traction sensors 36 , in one embodiment, are part of an anti-lock braking system (ABS). ABS compares vehicle speed with tire speed. When the two differ by more than a predetermined amount, the tire is determined to be slipping. ABS is simply one example; any suitable traction sensor can be used.
A battery 40 is coupled to rear axle motor 18 and front axle motor 28 to provide electrical energy or to absorb electrical, depending on operational mode. Battery 40 may also be electronically coupled to ECU 38 via sensors to monitor state of charge of the battery, battery health, etc. In one embodiment, battery 40 is a high voltage battery to facilitate large power extraction from or storage into the battery.
In one embodiment, ECU 38 is coupled to a yaw rate sensor 42 , a sensor coupled to a steering wheel 44 , and a variety of other sensors 46 , such as a vehicle speed sensor, temperature sensors, transmission sensors, pressure sensors, and acceleration sensors. In embodiments without yaw rate sensor 42 , yaw rate may be estimated based on signals from other sensors 46 .
An HEV is shown in FIG. 1 . In an alternative embodiment, the vehicle is an electric vehicle (EV) having a front axle motor and a rear axle motor. In such an embodiment, the following components are no longer included: clutch 26 , chain drive 30 , clutch 32 , and engine 34 . In some embodiments, transmission 24 is also not included.
In FIG. 2A , a vehicle 50 , either a HEV or EV, is shown during a turning maneuver. Wheels coupled to a front axle 52 are caused to turn via a steering input by the driver to the steering wheel (not shown). By the amount that the driver has turned the steering wheel, a desired path 56 for vehicle 50 can be determined. An example of an oversteer path 58 and an understeer path 60 are shown in FIG. 2A . To cause vehicle 50 to track along desired path 56 instead of oversteer path 58 , torque is increased to front axle 52 . Such a torque increase is possible by increasing torque provided by engine 34 or front axle motor 28 , such as shown in FIG. 2B . A torque increase from front axle torque 28 is much more rapid than a torque increase from engine 34 . Engine 34 suffers from intake manifold filling delays that hamper the engine's ability to rapidly increase engine torque. To rapidly respond to a determination that vehicle 50 is on an oversteer path 58 , torque generated by front axle motor 28 is increased. In one example, front axle motor 28 is being operated as a motor, or not at all, when the command for increased torque is received. In this case, front axle motor 28 is commanded to provide a positive torque. In another example, front axle motor 28 is being operated as a generator when the command for increased torque is received. In this case, front axle motor 28 is commanded to reduce electrical generation. If a greater increase in torque is required than can be achieved by reducing electrical generation, front axle motor 28 is commanded to change from operating as a generator to operating as a motor. A torque increase, by commanding front axle motor 28 to apply torque to the front axle, causes the longitudinal propulsion of vehicle 50 to exceed the operator's request. Thus, in one embodiment, rear axle motor 18 applies a braking torque to axle 16 . The torque increase to axle 20 and the torque decrease to axle 16 are determined to provide the desired path and longitudinal propulsion of vehicle 50 .
To respond to a determination that vehicle 50 is on an understeer path 60 , torque is supplied to rear axle 16 by rear axle motor 18 , such as that shown in FIG. 2C . To maintain the longitudinal propulsion of vehicle 50 , front axle motor 28 is commanded to reduce torque applied to front axle 20 .
In FIG. 3 , a tire force limit characteristic is plotted for the positive quadrant of the traction field. This is sometimes referred to as the friction circle 70 . Because tires may be optimized for lateral or longitudinal traction, the family of curves 72 (as a function of slip angle) is not a circle, but an ellipse. The friction limit for a tire is determined by the coefficient of friction times the load. The available friction can be used for lateral force, longitudinal force, or a combination of the two. Thus, the curves in FIG. 3 show the limit of friction, with the tire slipping if the combination of the longitudinal and lateral forces causes falls outside the curve corresponding to the slip angle. A positive longitudinal force is an acceleration force and a negative longitudinal force is a braking force. By following one of the family of limit curves, it can be seen that when the tire longitudinal force increases, the available lateral force decreases and vice versa.
To supplement the available friction available to tires associated with one axle, if appropriate hardware is available on the vehicle, torque or motive force can be redistributed between the front and rear axles. For example, when propulsive force is redistributed from the rear axle to the front axle, the front axle lateral force will decrease ΔF yf and the rear axle lateral force will increase ΔF yr . As a result, the vehicle yaw rate state will be changed and the variation of yaw moment is calculated as:
F yf — new =F yf +ΔF yf
F yr — new =F yr +ΔF yr
ΔM yaw =ΔF yf l f −ΔF yr l r
where F yf — new and F fr — new are the resultant front axle and rear axle lateral forces after the traction torque redistribution. In FIG. 2D , l f is shown as the distance between the center of gravity 80 of vehicle 50 and front axle 52 ; and l r is shown as the distance between the center of gravity 80 and rear axle 54 . By taking advantage of advanced control methodology, such an auxiliary yaw moment, ΔM yaw can be utilized either to enhance steering capability or to restrict excessive lateral vehicle dynamics without compromising the vehicle longitudinal performance. In a left turn maneuver, a positive ΔM yaw may be used to correct excessive vehicle oversteer, such as shown in FIG. 2B . A negative ΔM yaw may be used to compensate excessive vehicle understeer, such as shown in FIG. 2C .
The wheel torque that can be redistributed may be limited, however, due to the desire to avoid inducing wheel spin, i.e., insufficient traction between the tire and the surface, and limitations of the battery to provide the desired level of current to the traction motor due to the state of charge of the battery being insufficient or due to the temperature of the battery being too high.
The total available wheel torque to be redistributed depends on the current torque request level and the traction condition on the ground. To avoid control-induced wheel spin, a wheel slip controller/regulator is embedded in the traction controller at each axle to monitor the wheel slip and to regulate the wheel slip to a commanded optimal slip setpoint. In the presence of a solely electrical driven axle, the amount of total torque redistribution level may be further restricted by the vehicle's instantaneous power limit, battery discharge limit (a function of State of Charge (SOC) and temperature), electrical vehicle control mode and motor torque limit. All these factors will finally determine the maximum ΔM yaw available for vehicle dynamic controls.
In FIG. 4 , one embodiment of a control scheme is shown in a flowchart. The control scheme beginning with a turning request in block 100 . In block 102 , desired and actual vehicle yaw rates, γ des and γ act , and desired and actual sideslip angles, β des , and β act , are determined based on driver inputs, sensor data, and vehicle dynamic states, such as vehicle speed, yaw rate, lateral acceleration, and longitudinal acceleration. It is desirable to minimize both yaw rate error, γ des −γ act , and body slip angle error, β des , and β act . However, providing a yaw rate adjustment does not simultaneously minimize both errors. In block 104 , an optimized solution can be found, by minimizing a control objective function, such as:
J
=
∫
0
∞
(
(
Z
act
-
Z
des
)
T
Q
(
Z
act
-
Z
des
)
+
Δ
M
des
2
R
)
ⅆ
t
.
In the above equation Z act =[β act ,r act ] T and Z des =[β des ,r des ] T . Q and R are positive definite cost weighting matrices. A desired yaw moment, Δ des is determined. In block 108 , a desired wheel torque partition request is determined with total wheel torque request 106 , based on driver input, as an input to block 108 .
In block 114 , it is determined whether the torque partitions to the two axles are to be limited. For example, if the battery is not charged, then the motor can provide no torque to the axle. Thus, state of battery charge 112 is an input to block 114 . Or, if it is determined that by commanding the torque computed in block 104 to one of the axles would cause wheels coupled to that axle to slip, the torque determined in block 106 is a torque that would avoid such a slip condition. Thus, wheel slip conditions 110 are input to block 114 . If no limits are applied, there is no adjustment to the desired wheel torque (block 108 ) in block 114 . The torque partitions of block 114 are commanded to the axles in block 116 . Control passes to block 118 , in which it is determined if the operator is still commanding a turn to the vehicle. If not, the control scheme ends in block 120 . If so, control passes back to block 102 for repartitioning of torque between the axles throughout the turn.
While the best mode has been described in detail, those familiar with the art will recognize various alternative designs and embodiments within the scope of the following claims. Where one or more embodiments have been described as providing advantages or being preferred over other embodiments and/or over background art in regard to one or more desired characteristics, one of ordinary skill in the art will recognize that compromises may be made among various features to achieve desired system attributes, which may depend on the specific application or implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. For example, it may be desirable to have an extensive set of sensors to provide an accurate assessment of the vehicle's movement. However, to maintain a desirable cost structure, a satisfactory estimation of some vehicle quantities may be ascertained by inferring from a lesser set of sensor data. The embodiments described as being less desirable relative to other embodiments with respect to one or more characteristics are not outside the scope of the disclosure as claimed.
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A system for distributing propulsion to front and rear axles of a vehicle includes: a front axle motor coupled to the front axle and a rear axle motor coupled to the rear axle. An electronic control unit (ECU) electronically coupled to the motors commands the rear axle motor to increase torque supplied to the rear axle during understeer and commands the front axle motor to increase torque supplied to the front axle during oversteer. A method to distribute propulsion to front and rear axles of a vehicle includes estimating actual yaw rate, estimating desired yaw rate, providing electrical energy to the front axle motor during oversteer, and providing electrical energy to the rear axle motor during understeer. Additionally, electrical energy may be extracted from the rear axle motor during oversteer and electrical energy may be extracted from the front axle motor during understeer.
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BACKGROUND OF THE INVENTION
This invention relates generally to smelting furnaces and to the production of steels, and more particularly to a furnace for producing steels with steel scrap and the like as a raw material.
It is well known that the furnace wall of a furnace for melting metal must have excellent thermal properties such as heat resistance, heat insulation, high strength at high temperature, and erosion resistance similarly as in the case of ordinary heating furnaces. However, in a steel producing furnace, particularly that wherein steel is produced with steel scrap as a raw material, a high concentration of thermal energy is applied to the furnace thereby to elevate the working efficiency, and for this reason, the temperature of the interior of the furnace rises to a very high value.
Consequently, the firebricks lining the furnace tend to be damaged severely, and hence frequent maintenance (or periodical repairs) and replacement of the firebricks are required. Furthermore, even during operation, spalling and erosion caused by the spattering of oxidized metal have frequently and unavoidably made it necessary to interrupt the operation of the furnace at time, other than those for periodical maintenance. Frequent interruptions of furnace operation reduces the steel quantity thereby produced, and hence elevates the production cost.
In order to avoid the above described difficulties in the known furnaces, use is made of improved bricks such as basic high burned bricks and the like, which are baked at a higher temperature than the ordinary firebricks. However, so far as we are aware, none of these firebricks could satisfactorily overcome the aforementioned difficulties of the conventional furnaces.
It is also known that so-called carbonaceous bricks have a softening temperature in a range of from 1,500° C to 1,900° C, and the heat resistance thereof is far superior to those of any of the conventional firebricks. Furthermore, the real density of a carbonaceous brick is approximately 3,000 kg/m 3 , which is much higher than those of other bricks, and the specific heat thereof is 0.2 Kcal/kg°C. A carbonaceous brick also has high strength at high temperatures, and the resistance thereof to spalling is much higher than those of the ordinary firebricks.
However, a carbonaceous brick has drawbacks such as high susceptivity to oxidation, and low resistance to slag attack at high temperatures. In addition, the thermal conductivity of the carbonaceous brick is almost ten-times higher than that of the ordinary firebricks. These disadvantageous properties of carbonaceous bricks are so significant that it has been considered heretofore that carbonaceous bricks are not suitable for furnace walls despite the aforementioned advantageous features.
SUMMARY OF THE INVENTION
An important feature of the present invention is the provision of a furnace for producing steels wherein the aforementioned carbonaceous bricks are used in major part of the furnace wall, whereby the heat resistance, the strength at high temperatures, and the anti-spalling nature of the furnace is substantially improved.
Another feature of the invention is the provision of a furnace for producing steels wherein a part of the furnace wall, whose lower edge is spaced upward from the upper surface of the slag layer by a predetermined distance, is made of carbonaecous bricks, and water-cooling means are provided in this part of the furnace wall, so that while the advantageous properties of the carbonaceous bricks are fully utilized, the effects of the undesirable properties of the same bricks, such as the susceptibility to oxidation, low slag resistance, and tendency to be eroded by the spattered oxidized metal, can be substantialy reduced.
Still another feature of the invention is the provision of a steel producing furnace wherein the aforementioned water-cooling means is provided in the form of cooling-water boxes inserted in the above described part of the furnace wall, whereby the construction of the furnace and the handling of the water-cooling pipe lines can be greatly simplified.
An additional feature of the invention is the provision of a furnace for producing steels wherein a plurality of the cooling-water boxes are provided in the furnace wall, whereby the replacement thereof in the event of leakage trouble can be greatly facilitated.
A furnace for producing steel according to the present invention comprises a bottom portion, a furnace wall erected around said bottom portion for defining a part containing molten steel, a carbonaceous brick lining provided on a wall part of the interior surface of said furnace wall in such a manner that the lower edge of said wall part is spaced apart upward by a predetermined distance from the surface of a slag layer formed on the surface of the molten steel, and means for water-cooling said part of the furnace wall-lined with carbonaceous bricks.
The nature, principle, the utility, and further features of the invention will be more fully understood from the following detailed description of the invention when read in conjunction with the accompanying single drawing, which is an elevation, in vertical section, showing a preferred embodiment of the invention.
BRIEF DECRIPTION OF THE DRAWING
The single FIGURE of the accompanying drawing is an elevation in vertical section schematically showing a furnace according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the accompanying drawing, there is indicated a furnace 1 comprising a dish-shaped bottom portion 1a, a furnace wall 1b erected on and around the periphery of the bottom portion 1a, and a roof portion 1c provided to cover the upper end of the furnace wall 1b. Molten metal produced in the furnace from a starting material such as scrap steel is collected in the lower part of the furnace inclusive of the bottom portion 1a and a lower part of the furnace wall 1b. Ordinarily, the surface of the molten metal is covered by a slag layer collected on the surface of the molten metal.
According to the present invention the inner surface of a part, designated at 3, of the furnace wall 1b, ranging from approximately 100mm above the surface 2 of the slag layer to the upper end of the furnace wall 1b is lined with carbonaceous bricks. Also according to the invention, a required number (two in the illustrated example) of water-cooling boxes 4 are provided in this part 3 of the furnace wall 1b in such a manner that the lowest box is located at a position separated upwardly from the surface 2 of the slag layer by a distance ranging from 300mm to 500mm. The second lowest box is provided at a position upwardly separated from the lowest box by about 400mm, and succeeding water-cooling boxes, if any, are provided in the same manner with a distance of approximately 400mm maintained therebetween.
Each of the boxes 4 may be of a rectangular cross-section which, when the thickness of the furnace wall inclusive of the carbonaceous brick lining is assumed to be approximately 350mm, has a thickness of about 200mm and a height of about 130mm. Each of the water-cooling boxes 4 may be of a continuous construction of an annular shape around the furnace wall. Alternatively, each of the thus annularly formed water-cooling boxes 4 may be divided along its circumference into a plurality of blocks (three blocks in this example). In either of the cases, each of the annular boxes or each of the blocks of the boxes, are connected with both a water supplying pipe line 5a and a water discharging pipe line 5b, so that cooling water can be circulated therethrough through these pipe lines 5a and 5b. Since the water-cooling boxes 4 are thus divided, the maintenance and replacement of damaged parts of the cooling system can be substantially facilitated.
Although it has been described that two of the water-cooling boxes each divided into three blocks are provided in the described example, three or four water-cooling boxes may be arranged vertically at a predetermined interval, and each of the boxes may be divided into from 2 to 4 blocks depending on the size of the furnace.
Carbonaceous bricks used for lining the aforementioned part 3 of the furnace wall 1b are of a carbon content of more than 99%, a porosity of from 25 to 30%, a bulk density of from 1.5 to 1.6 kg/l, and a refractoriness of about 3,400° C.
Since the composition of the furnace according to the present invention is as described above, the upper part 3 of the furnace wall can be cooled effectively because of the aforementioned high thermal conductivity of the carbonaceous bricks when cooling water is circulated through the water-cooling boxes via the water supplying pipe line 5a and the water discharging pipe line 5b. Thus, excessive high temperature of the carbonaceous bricks, which tends to cause erosion of the bricks at the time when oxidized metal such as iron oxide is spattered onto the surfaces of the bricks, can be avoided, and the advantageous features of the carbonaceous bricks such as the high heat resistance, high strength at high temperatures, and high spalling resistance can be fully utilized at the operating temperature of the furnace.
As a result of our experiments, it has been found that the furnace of this invention can withstand more than 250 heats of operations without any repair at a high productivity of 15,000 tons of steel in 20 days, while the conventional furnaces have become useless after about 50 heats of operations producing about 10,000 tons of steel in 20 days with the furace being repaired during these operations.
Furthermore, it was made apparent that the unit consumption of the bricks (quantity of bricks used for building and repairing furnace versus the quantity of steel produced during the life time of the furnace) can be reduced to as low as 1.7kg per one ton of the product, which is less tha one half of the quantity required for the conventional furnaces.
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A furnace for producing steel from steel scrap and the like is constructed in a manner such that the interior surface of the furnace wall upward from a level spaced apart by a predetermined distance from the surface of a slag layer formed on the molten steel is lined with carbonaceous bricks, and water-cooling means are provided in this part of the furnace wall.
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FIELD OF THE INVENTION
[0001] The invention relates to a gas storage system and method. More particularly, the invention relates to a system comprising glass capillaries suitable to be inserted with gas in high pressure, contain it and allow its extraction.
BACKGROUND OF THE INVENTION
[0002] Hydrogen is often used as a fuel substance. It is highly recommended since it is non-toxic and therefore it is safe to produce, store (even in large amounts), and transport. There are many other advantages to hydrogen such as the fact that it is lighter than air, carbon-free, exceptionally clean, can be produced from a variety of resources, and the only byproducts are water and heat.
[0003] Hydrogen is often used in combination with fuel cells that are used all over the world. Stationary cells are often used for emergency power systems as a backup power supply system, and they are used in hospitals, nursing homes, office buildings, etc. Portable cells can supply power for cars, boats, submarines, spacecraft, etc. A fuel cell can also charge different kinds of batteries for a variety of electronic devices.
[0004] A fuel cell that comprises hydrogen is an electrochemical cell which converts chemical energy into electric current. The chemical reaction is created when the hydrogen comes into contact with an oxidant. When using hydrogen fuel cells, it is less noisy than in other fuel systems, and most importantly—there is no emission of hazardous materials.
[0005] Hydrogen must be stored in a suitable containing system, which can endure high pressure, resulting from containing compressed hydrogen. In order to deliver the hydrogen to different locations, the containing system should be portable. Nowadays, most containing systems that meet those requirements are built from metal materials, alloys and/or composites, and the use of such materials makes the containing system relatively heavy, and therefore limits its portability and range of uses.
[0006] WO2011/080746 teaches a storage tank comprising a plurality of hollow micro-cylinders having each an end sealed with a plug made of an easily meltable alloy and heating coils wound around the micro-cylinder ends, which are heated to melt the plug and thereby to liberate the hydrogen gas from said array. This type of arrangement is complex and presents practical problems that prevent it from being a satisfactory industrial solution.
[0007] Therefore, there is a need for a simple, efficient, refuelable and low-cost solution that would permit the storage of hydrogen gas in a relatively light-weight storage. It is an object of the invention to provide a system and method that overcome the drawbacks of the prior art.
[0008] Other objects and advantages of the invention will become apparent as the description proceeds.
SUMMARY OF THE INVENTION
[0009] A device for the storage of compressed hydrogen gas comprises a plurality of glass capillary tubes each having a sealed extremity and an open extremity, wherein said plurality of glass capillary tubes is sheathed in an external tubular cover, and wherein the open end of a bundle of said tubular covers is housed in an adaptor, and wherein said adaptor is suitable to allow compressed hydrogen gas to be added to, and to prevent said hydrogen gas from escaping from, said glass capillary tubes.
[0010] In one embodiment of the invention the bundle of tubular covers is connected to the adaptor at the open end with gluing material. In another embodiment of the invention the gluing material is an epoxy resin. The device may further comprise sealing material.
[0011] In one embodiment of the invention the adaptor is provided with a sealing valve, which may be integral with the adaptor or may be coupled thereto.
[0012] The invention is also directed to a method for generating a capillary tube with one closed end, which is suitable for use with the device of the invention, comprising providing an open-ended capillary tube, applying a glass cupping to one open end and then melting the glass at said end.
[0013] Further encompassed by the invention is a system for the storage of compressed hydrogen gas, comprising an array of two or more devices according to claim 1 , said two or more devices being connected to a common conduit for the addition of gas to, and withdrawal of gas from, the storage devices.
[0014] Fuel cells comprising as the hydrogen-storage element one or more devices according to the invention, and their uses, also form part of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In the drawings:
[0016] FIG. 1 is a perspective view of an MC (“multi-capillary” structure), according to one embodiment of the invention;
[0017] FIG. 2 is a perspective view of a group of MCs-MMC (“multi multi-capillary” structure) of FIG. 1 ;
[0018] FIG. 3 is an array of MMCs, according to another embodiment of the invention;
[0019] FIG. 4 is a diagram of a fuel-providing system comprising an array of MMC; and
[0020] FIG. 5 is another diagram of a fuel-providing system further comprising a check valve and a release valve.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The invention relates to a gas-containing system and method. The following description refers to hydrogen gas, but obviously the system may be exploited to store additional and/or alternative gases, as long as the pressure of said gases does not exceed the maximum pressure that the system can accommodate.
[0022] The gas is caused to flow into a thin glass tube, which will also be referred to herein as “capillary”. The cross-section of the capillary can be round or of any other geometrical shape, such as a hexagonal.
[0023] The glass tubes are made of a material having high tensile strength a 20 and low mass density ρ. For example, materials that meet the condition σ/ρ> — 1700 MPa-cm3/g are suitable for the glass tubes. Examples of materials suitable for the capillary tubes include, but are not limited to, borosilicate glass, MgAlSi glass, S-2 Glass™, R-glass available from Saint-Gobain Vetrotex Textiles, T-Glass available from Nitto Boseki Co., Ltd. (Nittobo), fused quartz, polymers (e.g., Kevlar™, 25 TwaronXM), etc.
[0024] Generally, the glass tubes can have any desired length. The external diameter of the glass tubes can be in the range of about 1 micrometer to about 500 micrometers. A number of the capillary glass tubes in one MMC (see FIG. 2 ) can, for example, be in the range of 50 to 1,000,000. These dimensions of the capillaries are strongly dependent on pressure resistance, possibility of easy manufacturing etc. whereas the dimensions of the arrays (various number of MMC) are dependent on the manufacturing process, opening procedure and the actual application.
[0025] Methods for fabrication of hollow microcylinders (i.e., capillary glass tubes) and microcylindrical array structures are known per se. In particular, various microcylindrical (capillary) arrays made from glass and/or plastics are widely used in x-ray optics and photonics. Generally, the process of fabrication of microcylindrical arrays is divided into three main stages: (i) drawing capillaries with relatively large diameter, (ii) re-drawing them 10 into a bundle of capillaries with smaller diameter, and (iii) sintering capillaries into the array. Existing technology enables one to produce vast arrays with a capillary diameter down to 1 micron or even less, and a wall thickness-to-diameter ratio less than 5%. For example, capillary arrays suitable for the purpose of the present invention can be obtained from Paradigm Optics, Inc.; 9600 NE 126th Ave, Suite 2540 Vancouver, Wash. 15 98682 USA; Hilgenberg GmbH, Strauchgraben 2, D-34323 Malsfeld, Germany; INCOM 294 Southbridge Road, Charlton, Mass. 01507; etc.
[0026] A group of capillaries is attached together to form a “multi-capillary” structure (MC). The MC outer cover also has a tubular shape. FIG. 1 shows an MC 101 with a hexagonal cross-section, according to one embodiment of the invention. One end of the MC 101 is sealed by a glass cupping element, which in this example is shaped as a half sphere 102 , hereinafter—“half-sphere”. For better orientation, the end that comprises a half-sphere is designated as the bottom. The connection between a tube and a half-sphere is performed by melting the glass while applying pressure on both parts, one against the other.
[0027] As shown in FIG. 2 , a number of MCs can be attached and form an even larger storage system—“multi-multi-capillary” (MMC). An MC or a group of MCs—MMC are connected to an adaptor at the open (top) end of the capillaries—a unit which allows the addition and release of a gas into and from each tube. A valve can be provided in the adaptor or connected thereto, to prevent gas from escaping from the storage. FIG. 2 shows an MMC 201 connected to an adaptor 202 . The attachment of an MC or an MMC to an adaptor can be performed for example by a glue such as epoxy resin. If necessary after the attachment of the adaptor to the MC/MMC, an additional sealing material can be used. One example of a suitable adaptor is one that is made of stainless steel 1.4301 and designed to securely hold the glass-steel connection at pressure up to 40 MPa.
[0028] An exemplary adaptor made of SS 1.4301 has a wall thickness of 0.75 mm and is suitable to store gas at a pressure of up to 40 MPa, it is glued for a length of the glass sheath of 53 mm using Loctite 9483 A&B. The resin is cures at 30° C. for 24 hours.
[0029] As shown in FIG. 3 , another form of storage system can be an array of MMCs, according to another embodiment of the invention. Every MMC 301 is connected to its own adaptor 302 , and every adaptor is connected to a conduit 303 . When all of the MMCs in the array are connected to one or more conduits, it provides for a convenient addition and extraction of gas into and from the storage system, and thus the procedure is performed only once for every group of MMCs connected to the same conduit 303 .
[0030] FIG. 4 is a diagram of a fuel-providing system comprising an array of MMC. The fuel cell 401 is where the chemical reaction occurs, but the gas used in the process needs to enter the fuel cell 401 at a relatively low pressure, for example 0.2 MPa, and since it leaves the MMCs 402 at a pressure of up to 20 MPa, in this illustrative scheme a pressure regulator 403 is provided between the fuel cell 401 and the MMCs 402 . A fast coupling 404 can also be provided.
[0031] FIG. 5 is another diagram of a fuel-providing system further comprising a check valve 501 and a release valve 502 . The additional two components are provided in this specific embodiment of the invention for safety reasons. The check valve 501 can detect hazardous situation relaying on pressure values measured by said valve 501 . If the pressure in the system is too high, the release valve 502 is operated by check valve 501 , for pressure release and regulation.
[0032] All the above description has been provided for the purpose of illustration and it is not meant to limit the invention in any way except as provided for by the appended claims.
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A device for the storage of compressed hydrogen gas comprises a plurality of glass capillary tubes each having a sealed extremity and an open extremity, wherein said plurality of glass capillary tubes is sheathed in an external tubular cover, and wherein the open end of a bundle of said tubular covers is housed in an adaptor, and wherein said adaptor is suitable to allow compressed hydrogen gas to be added to, and to prevent said hydrogen gas from escaping from, said glass capillary tubes.
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CROSS-REFERENCE
The present application claims priority to U.S. Provisional Patent Application No. 61/083,215, filed on Jul. 24, 2008, and is related to U.S. patent application Ser. No. 11/961,650, filed Dec. 20, 2007, and U.S. Provisional Patent Application No. 60/871,698 filed on Dec. 22, 2006, the entirety of these three applications is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to watercraft having a reverse gate and methods of operating the reverse gate.
BACKGROUND OF THE INVENTION
In jet propelled watercraft, such as personal watercraft or sport boat, the watercraft can be propelled in reverse by lowering a reverse gate behind the output of the water jet thus redirecting the jet toward the front of the watercraft which creates a thrust in the reverse direction. The reverse gate is actuated by a hand activated reverse gate operator which, when pulled, lowers the reverse gate in front of the water jet. By actuating a throttle operator of the watercraft, the amount of thrust generated by the jet propulsion system changes. Therefore, by controlling the position of the reverse gate and the amount of thrust generated by the jet propulsion system, by actuating the reverse gate operator and the throttle operator respectively, the driver of the watercraft can control the amount of reverse thrust being generated.
The reverse thrust being generated when the reverse gate is lowered can also be used to decelerate the watercraft. However, when the watercraft is moving at relatively high speeds, if the driver of the vehicle applies to much reverse thrust, it can cause the stem of the watercraft to lift and the bow of the watercraft to dip. This can result in an undesirably unstable riding condition.
Also, when the watercraft is moving at high speeds, the thrust being generated is also usually high. The high thrust being generated may in some cases prevent the reverse gate from being lowered as the thrust pushes the reverse gate back towards its stowed position when the reverse gate comes in contact with the jet of water being expelled by the jet propulsion system. Therefore, in these cases, in order to decelerate the watercraft, the driver needs to first release the throttle operator in order to reduce the thrust being generated by the jet propulsion system. The driver then needs to actuate the reverse gate operator in order to lower the reverse gate. Finally, the driver needs to actuate the throttle operator sufficiently to generate a reverse thrust, but not too much so as to avoid the above-mentioned problem.
Therefore, there is a need for a way to allow the driver of a watercraft to control the amount of reverse thrust being generated when the reverse gate is lowered while preventing the generation of too much reverse thrust when the watercraft is moving at relatively high speeds.
SUMMARY OF THE INVENTION
It is an object of the present invention to ameliorate at least some of the inconveniences present in the prior art.
It is also an object of the present invention to provide a method of controlling a jet propelled watercraft where the driver controls the amount of reverse thrust being generated below a predetermined speed, but where the amount of reverse thrust being generated above the predetermined speed is at least partially controlled independently of driver inputs.
It is another object of the present invention to provide a watercraft implementing at least an embodiment of the above method.
In one aspect, the invention provides a method of controlling a watercraft. The watercraft has a hull, a deck disposed on the hull, a seat disposed on the deck, an engine compartment defined between the hull and the deck, an engine disposed in the engine compartment, an electronic control unit, a jet propulsion system connected to the hull and operatively connected to the engine, a throttle operator for controlling the engine, a reverse gate operator, and a reverse gate operatively connected to the hull. The reverse gate is movable between a first stowed position and a second position in which the reverse gate redirects a jet of water expelled from the jet propulsion system. The reverse gate is in operative connection with the reverse gate operator. The method comprises actuating the reverse gate operator, sensing a speed of the watercraft, sensing a position of the throttle operator, controlling a thrust generated by the jet propulsion system based at least on the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is below a predetermined watercraft speed, controlling the thrust generated by the jet propulsion system at least in part independently of the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed, and moving the reverse gate to the second position in response to the actuation of the reverse gate operator.
In an additional aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed, the thrust generated by the jet propulsion system is controlled independently of the position of the throttle operator.
In a further aspect, controlling the thrust generated by the jet propulsion system includes controlling a speed of rotation of the engine.
In an additional aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed: controlling the speed of rotation of the engine includes controlling the speed of rotation of the engine to be at or below a reverse gate actuation speed in response to the actuation of the lever, the reverse gate is moved to the second position once the speed of rotation of the engine is at or below the reverse gate actuation speed, and once the reverse gate is moved to the second position, controlling the speed of rotation of the engine includes controlling the speed of rotation of the engine in order to decelerate the watercraft.
In a further aspect, controlling a speed of rotation of the engine in order to decelerate the watercraft includes increasing the speed of rotation of the engine above the reverse gate actuation speed.
In an additional aspect, controlling the speed of rotation of the engine comprises adjusting a position of a throttle valve of the engine.
In a further aspect, controlling the speed of rotation of the engine comprises adjusting at least one of an ignition timing and an injection timing of the engine.
In an additional aspect, the method also comprises sensing an actuated position of the reverse gate operator. When the reverse gate operator is actuated and the speed of the watercraft is below the predetermined watercraft speed, moving the reverse gate to the second position includes adjusting the second position of the reverse gate based at least on the actuated position of the reverse gate operator.
In a further aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed, moving the reverse gate to the second position includes adjusting the second position of the reverse gate independently of an actuated position of the reverse gate operator.
In an additional aspect, the method also comprises adjusting a position of a throttle valve of the engine based on the position of the throttle operator when the reverse gate operator is not actuated.
In a further aspect, the method also comprises sensing an actuated position of the reverse gate operator, and controlling the thrust generated by the jet propulsion system at least in part independently of the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed includes controlling the thrust generated by the jet propulsion system based at least on the speed of the watercraft and the position of the reverse gate operator.
In an additional aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed, the second position of the reverse gate is a predetermined position independent of the position of the reverse gate operator.
In a further aspect, the method also comprises sensing an actuated position of the reverse gate operator; and controlling the thrust generated by the jet propulsion system at least in part independently of the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed includes adjusting the thrust generated by the jet propulsion system based on changes in the position of the reverse gate operator.
In an additional aspect, the method also comprises returning the reverse gate operator to a non-actuated position; and moving the reverse gate to a neutral position in response to the reverse gate operator returning to the non-actuated position.
In a further aspect, controlling the thrust generated by the jet propulsion system at least in part independently of the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed includes controlling the thrust generated by the jet propulsion system at least in part independently of the position of the throttle operator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed until the speed of the watercraft is less than or equal to an other predetermined watercraft speed. The other predetermined watercraft speed is less than the predetermined watercraft speed. The method also comprises moving the reverse gate to a neutral position when the speed of the watercraft is less than or equal to the other predetermined watercraft speed.
In another aspect, the invention provides a watercraft having a hull, a deck disposed on the hull, an engine compartment defined between the hull and the deck, an engine disposed in the engine compartment, a throttle body having a throttle valve and being in fluid communication with the engine, a jet propulsion system connected to the hull and operatively connected to the engine, an electronic control unit (ECU) associated with the watercraft for controlling at least an operation of the engine, a throttle operator being movable between an idle position and an actuated position, a throttle operator position sensor associated with the throttle operator for sensing a position of the throttle operator, the throttle operator position sensor being in electronic communication with the ECU, a throttle valve actuator operatively connected to the throttle valve and in electronic communication with the ECU, an engine speed sensor for sensing a speed of rotation of the engine and being in electronic communication with the ECU, a watercraft speed sensor for sensing a speed of the watercraft and being in electronic communication with the ECU, a reverse gate operatively connected to the hull, the reverse gate being movable between a first stowed position and a second position in which the reverse gate redirects a jet of water expelled from the jet propulsion system, a reverse gate actuator operatively connected to the reverse gate for moving the reverse gate between the first stowed position and the second position, and being in electronic communication with the ECU, and a reverse gate operator associated with the watercraft and being in electronic communication with the ECU for controlling the reverse gate actuator. The ECU causes the reverse gate actuator to move the reverse gate to the second position when the reverse gate operator is actuated. The ECU sends a first signal to the throttle valve actuator to control the throttle valve actuator when the reverse gate operator is actuated and the speed of the watercraft is below a predetermined watercraft speed. The first signal is based at least on the position of the throttle operator. The ECU sends a second signal to the throttle valve actuator to control the throttle valve actuator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed. The second signal is independent at least in part of the position of the throttle operator.
In a further aspect, the second signal is independent of the position of the throttle operator.
In an additional aspect, the second signal controls the throttle valve actuator such that the speed of rotation of the engine is controlled to be at or below a reverse gate actuation speed. When the second signal is sent to the throttle valve actuator, the ECU causes the reverse gate actuator to move the reverse gate to the second position once the speed of rotation of the engine is at or below the reverse gate actuation speed. Once the reverse gate is moved to the second position, the second signal controls the throttle valve actuator such that the watercraft decelerates in a controlled deceleration.
In a further aspect, once the reverse gate is moved to the second position, the second signal controls the throttle valve actuator such that the speed of rotation of the engine is increased above the reverse gate actuation speed.
In an additional aspect, a reverse gate operator position sensor is associated with the reverse gate operator for sensing a position of the reverse gate operator. The reverse gate operator position sensor is in electronic communication with the ECU. When the first signal is sent to the throttle valve actuator, the ECU causes the reverse gate actuator to move the reverse gate to the second position based at least on the position of the reverse gate operator.
In a further aspect, when the second signal is sent to the throttle valve actuator, the ECU causes the reverse gate actuator to move the reverse gate to the second position independently of the position of the reverse gate operator.
In an additional aspect, the ECU sends a third signal to the throttle valve actuator to control the throttle valve actuator when the reverse gate operator is not actuated. The third signal is based at least on the position of the throttle operator.
In a further aspect, a reverse gate operator position sensor is associated with the reverse gate operator for sensing a position of the reverse gate operator. The reverse gate operator position sensor is in electronic communication with the ECU. The second signal is based at least on the speed of the watercraft and the position of the reverse gate operator.
In an additional aspect, a handlebar is operatively connected to the deck. The throttle operator is disposed on the handlebar. The throttle operator is selected from a group consisting of a thumb-actuated throttle lever, a finger-actuated throttle lever, and a twist grip.
In a further aspect, the reverse gate actuator is an electric actuator.
In an additional aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed, the second position of the reverse gate is a predetermined position independent of the position of the reverse gate operator.
In a further aspect, a reverse gate operator position sensor is associated with the reverse gate operator for sensing a position of the reverse gate operator. The reverse gate operator position sensor is in electronic communication with the ECU. The second signal is based on changes in the position of the reverse gate operator.
In an additional aspect, the ECU causes the reverse gate actuator to move the reverse gate to a neutral position when the reverse gate actuator is returned to a non-actuated position from an actuated position.
In a further aspect, the ECU stops sending the second signal when the speed of the watercraft becomes less than or equal to an other predetermined watercraft speed. The other predetermined watercraft speed is less than the predetermined watercraft speed. The ECU causes the reverse gate actuator to move the reverse gate to a neutral position when the ECU stops sending the second signal.
In another aspect, the invention provides a method of controlling a watercraft. The watercraft has a hull, a deck disposed on the hull, a seat disposed on the deck, an engine compartment defined between the hull and the deck, an engine disposed in the engine compartment, an electronic control unit, a jet propulsion system connected to the hull and operatively connected to the engine, a throttle operator for controlling the engine, a reverse gate operator, and a reverse gate operatively connected to the hull. The reverse gate is movable between a first stowed position and a second position in which the reverse gate redirects a jet of water expelled from the jet propulsion system. The reverse gate is in operative connection with the reverse gate operator. The method comprises: actuating the reverse gate operator; sensing a speed of the watercraft; sensing a position of the throttle operator; moving the reverse gate to the second position in response to the actuation of the reverse gate operator; controlling a thrust generated by the jet propulsion system to be less than or equal to a first predetermined maximum thrust when the reverse gate operator is actuated and the speed of the watercraft is below a predetermined watercraft speed; and controlling the thrust generated by the jet propulsion system to be less than or equal to a second predetermined maximum thrust when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed. The second predetermined maximum thrust is less than the first predetermined maximum thrust.
In a further aspect, the second predetermined maximum thrust increases as the speed of the watercraft decreases.
In an additional aspect, controlling the thrust generated by the jet propulsion system includes controlling a speed of rotation of the engine.
In a further aspect, when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed: controlling the speed of rotation of the engine includes controlling the speed of rotation of the engine to be at or below a reverse gate actuation speed in response to the actuation of the lever; the reverse gate is moved to the second position once the speed of rotation of the engine is at or below the reverse gate actuation speed; and once the reverse gate is moved to the second position, controlling the speed of rotation of the engine includes controlling the speed of rotation of the engine in order to decelerate the watercraft.
In yet another aspect, the invention provides a watercraft comprising a hull, a deck disposed on the hull, an engine compartment defined between the hull and the deck, an engine disposed in the engine compartment, a throttle body having a throttle valve and being in fluid communication with the engine, a jet propulsion system connected to the hull and operatively connected to the engine, an electronic control unit (ECU) associated with the watercraft for controlling at least an operation of the engine, a throttle operator being movable between an idle position and an actuated position, a throttle operator position sensor associated with the throttle operator for sensing a position of the throttle operator, the throttle operator position sensor being in electronic communication with the ECU, a throttle valve actuator operatively connected to the throttle valve and in electronic communication with the ECU, an engine speed sensor for sensing a speed of rotation of the engine and being in electronic communication with the ECU, a watercraft speed sensor for sensing a speed of the watercraft and being in electronic communication with the ECU, a reverse gate operatively connected to the hull, the reverse gate being movable between a first stowed position and a second position in which the reverse gate redirects a jet of water expelled from the jet propulsion system, a reverse gate actuator operatively connected to the reverse gate for moving the reverse gate between the first stowed position and the second position, and being in electronic communication with the ECU, and a reverse gate operator associated with the watercraft and being in electronic communication with the ECU for controlling the reverse gate actuator. The ECU causes the reverse gate actuator to move the reverse gate to the second position when the reverse gate operator is actuated. The ECU sends a first signal to the throttle valve actuator to control the throttle valve actuator when the reverse gate operator is actuated and the speed of the watercraft is below a predetermined watercraft speed. A thrust generated by the jet propulsion system as a result of the first signal being sent to the throttle valve actuator is less than or equal to a first predetermined maximum thrust. The ECU sends a second signal to the throttle valve actuator to control the throttle valve actuator when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed. The thrust generated by the jet propulsion system as a result of the second signal being sent to the throttle valve actuator is less than or equal to a second predetermined maximum thrust. The second predetermined maximum thrust is less than the first predetermined maximum thrust.
In an additional aspect, the second predetermined maximum thrust increases as the speed of the watercraft decreases.
In a further aspect, the second signal controls the throttle valve actuator such that the speed of rotation of the engine is controlled to be at or below a reverse gate actuation speed. When the second signal is sent to the throttle valve actuator, the ECU causes the reverse gate actuator to move the reverse gate to the second position once the speed of rotation of the engine is at or below the reverse gate actuation speed. Once the reverse gate is moved to the second position, the second signal controls the throttle valve actuator such that the watercraft decelerates in a controlled deceleration.
In another aspect, the invention provides a method of controlling a watercraft. The watercraft has a hull, a deck disposed on the hull, a seat disposed on the deck, an engine compartment defined between the hull and the deck, an engine disposed in the engine compartment, an electronic control unit, a jet propulsion system connected to the hull and operatively connected to the engine, a throttle operator for controlling the engine, a reverse gate operator, and a reverse gate operatively connected to the hull. The reverse gate is movable between a first stowed position, a second position in which the reverse gate redirects a jet of water expelled from the jet propulsion system, and a neutral position intermediate the first stowed position and the second position. The reverse gate is in operative connection with the reverse gate operator. The method comprises: a) actuating the reverse gate operator; b) sensing a speed of the watercraft; c) controlling the thrust generated by the jet propulsion system in a reverse mode when the reverse gate operator is actuated and the speed of the watercraft is below a predetermined watercraft speed; d) controlling the thrust generated by the jet propulsion system in a controlled deceleration mode when the reverse gate operator is actuated and the speed of the watercraft is above the predetermined watercraft speed; e) moving the reverse gate to the second position in response to the actuation of the reverse gate operator; f) returning the reverse gate operator to a non-actuated position after the actuation of the reverse gate operator; and g) moving the reverse gate to the neutral position in response to the reverse gate operator returning to the non-actuated position.
In an additional aspect, steps c, d, and e are only carried out if the reverse gate operator has been actuated for a predetermined amount of time.
For purposes of this application, the terms “controlled deceleration” mean a gradual reduction in speed compared to an uncontrolled deceleration which may result in an abrupt reduction in speed which could cause the driver of the watercraft to lose control of the watercraft.
Embodiments of the present invention each have at least one of the above-mentioned objects and/or aspects, but do not necessarily have all of them. It should be understood that some aspect of the present invention that have resulted from attempting to attain the above-mentioned objects may not satisfy these objects and/or may satisfy other objects not specifically recited herein.
Additional and/or alternative features, aspects, and advantages of the embodiments of the present invention will become apparent from the following description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:
FIG. 1 illustrates a side view of a personal watercraft in accordance with the invention;
FIG. 2 is a top view of the watercraft of FIG. 1 ;
FIG. 3 is a front view of the watercraft of FIG. 1 ;
FIG. 4 is a back view of the watercraft of FIG. 1 ;
FIG. 5 is a bottom view of the hull of the watercraft of FIG. 1 ;
FIG. 6 is a perspective view, taken from a front, left side, of a sport boat in accordance with the invention;
FIG. 7 is a perspective view, taken from a rear, left side, of the sport boat of FIG. 6 ;
FIG. 8 is a side view of a jet propulsion system nozzle and reverse gate assembly where the reverse gate is mounted on the nozzle assembly with the reverse gate in a stowed position;
FIG. 9 is a side view of the jet propulsion system nozzle and reverse gate assembly of FIG. 8 with the reverse gate in a neutral position;
FIG. 10 is a perspective view, taken from a right side, of a transom of a watercraft illustrating a reverse gate mounted to the hull and in a stowed position;
FIG. 11 is a perspective view, taken from a left side, of the transom of FIG. 10 with the reverse gate in a reverse position;
FIG. 12 is a schematic representation of the various sensors and watercraft components that may be present in a watercraft in accordance with the present invention;
FIG. 13A is a schematic representation of an embodiment of a reverse gate actuation system of the sport boat of FIG. 6 ;
FIG. 13B is a schematic representation of an alternative embodiment of the reverse gate actuation system of FIG. 13A ;
FIG. 13C is a schematic representation of another alternative embodiment of the reverse gate actuation system of FIG. 13A ;
FIG. 14 is a logic diagram illustrating a method of controlling a watercraft in accordance with the present invention;
FIG. 15 is a logic diagram illustrating a portion of an alternative method of controlling a watercraft in accordance with the present invention; and
FIG. 16 is a logic diagram illustrating another method of controlling a watercraft.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The general construction of a personal watercraft 10 in accordance with this invention is shown in FIGS. 1-5 . The following description relates to one way of manufacturing a personal watercraft. Obviously, those of ordinary skill in the watercraft art will recognize that there are other known ways of manufacturing and designing watercraft and that this invention would encompass these other known ways and designs.
The watercraft 10 of FIG. 1 is made of a hull 12 and a deck 14 . The hull 12 buoyantly supports the watercraft 10 in the water. The deck 14 is designed to accommodate a rider and, in some watercraft, one or more passengers. The hull 12 and deck 14 are joined together at a seam 16 that joins the parts in a sealing relationship. Preferably, the seam 16 comprises a bond line formed by an adhesive. Of course, other known joining methods could be used to sealingly engage the parts together, including but not limited to thermal fusion, molding or fasteners such as rivets or screws. A bumper 18 generally covers the seam 16 , which helps to prevent damage to the outer surface of the watercraft 10 when the watercraft 10 is docked, for example. The bumper 18 can extend around the bow, as shown, or around any portion or all of the seam 16 .
The space between the hull 12 and the deck 14 forms a volume commonly referred to as the engine compartment 20 (shown in phantom). The engine compartment 20 accommodates an engine 22 , as well as a muffler, tuning pipe, gas tank, electrical system (battery, electronic control unit, etc.), air box, storage bins 24 , 26 , and other elements required or desirable in the watercraft 10 .
As seen in FIGS. 1 and 2 , the deck 14 has a centrally positioned straddle-type seat 28 positioned on top of a pedestal 30 to accommodate multiple riders in a straddling position. As seen in FIG. 2 , the seat 28 includes a first, front seat portion 32 and a rear, raised seat portion 34 . The seat 28 is preferably made as a cushioned or padded unit, or as interfitting units. The first and second seat portions 32 , 34 are removably attached to the pedestal 30 by a hook and tongue assembly (not shown) at the front of each seat and by a latch assembly (not shown) at the rear of each seat, or by any other known attachment mechanism. The seat portions 32 , 34 can be individually tilted or removed completely. Seat portion 32 covers an engine access opening defined by a top portion of the pedestal 30 to provide access to the engine 22 ( FIG. 1 ). Seat portion 34 covers a removable storage box 26 ( FIG. 1 ). A “glove compartment” or small storage box 36 is provided in front of the seat 28 .
As seen in FIG. 4 , a grab handle 38 is provided between the pedestal 30 and the rear of the seat 28 to provide a handle onto which a passenger may hold. This arrangement is particularly convenient for a passenger seated facing backwards for spotting a water skier, for example. Beneath the handle 38 , a tow hook 40 is mounted on the pedestal 30 . The tow hook 40 can be used for towing a skier or floatation device, such as an inflatable water toy.
As best seen in FIGS. 2 and 4 , the watercraft 10 has a pair of generally upwardly extending walls located on either side of the watercraft 10 known as gunwales or gunnels 42 . The gunnels 42 help to prevent the entry of water in the footrests 46 of the watercraft 10 , provide lateral support for the riders' feet, and also provide buoyancy when turning the watercraft 10 , since personal watercraft roll slightly when turning. Towards the rear of the watercraft 10 , the gunnels 42 extend inwardly to act as heel rests 44 . A passenger riding the watercraft 10 facing towards the rear, to spot a water-skier for example, may place his or her heels on the heel rests 44 , thereby providing a more stable riding position. Heel rests 44 could also be formed separately from the gunnels 42 .
Located on both sides of the watercraft 10 , between the pedestal 30 and the gunnels 42 are the footrests 46 . The footrests 46 are designed to accommodate the riders' feet in various riding positions. To this effect, the footrests 46 each have a forward portion 48 angled such that the front portion of the forward portion 48 (toward the bow of the watercraft 10 ) is higher than the rear portion of the forward portion 48 . The remaining portions of the footrests 46 are generally horizontal. Of course, any contour conducive to a comfortable rest for the riders could be used. The footrests 46 are covered by carpeting 50 made of a rubber-type material, for example, to provide additional comfort and traction for the feet of the riders.
A reboarding platform 52 is provided at the rear of the watercraft 10 on the deck 14 to allow the rider or a passenger to easily reboard the watercraft 10 from the water. Carpeting or some other suitable covering may cover the reboarding platform 52 . A retractable ladder (not shown) may be affixed to the transom 54 to facilitate boarding the watercraft 10 from the water onto the reboarding platform 52 .
Referring to the bow 56 of the watercraft 10 , as seen in FIGS. 2 and 3 , the watercraft 10 is provided with a hood 58 located forwardly of the seat 28 and a helm assembly 60 . A hinge (not shown) is attached between a forward portion of the hood 58 and the deck 14 to allow hood 58 to move to an open position to provide access to the front storage bin 24 ( FIG. 1 ). A latch (not shown) located at a rearward portion of hood 58 locks hood 58 into a closed position. When in the closed position, hood 58 prevents water from entering front storage bin 24 . Rearview mirrors 62 are positioned on either side of hood 58 to allow the rider to see behind the watercraft 10 . A hook 64 is located at the bow 56 of the watercraft 10 . The hook 64 is used to attach the watercraft 10 to a dock when the watercraft 10 is not in use or to attach to a winch when loading the watercraft 10 on a trailer, for instance.
As best seen in FIGS. 3 , 4 , and 5 , the hull 12 is provided with a combination of strakes 66 and chines 68 . A strake 66 is a protruding portion of the hull 12 . A chine 68 is the vertex formed where two surfaces of the hull 12 meet. The combination of strakes 66 and chines 68 provide the watercraft 10 with its riding and handling characteristics.
Sponsons 70 are located on both sides of the hull 12 near the transom 54 . The sponsons 70 have an arcuate undersurface that gives the watercraft 10 both lift while in motion and improved turning characteristics. The sponsons 70 are fixed to the surface of the hull 12 and can be attached to the hull 12 by fasteners or molded therewith. It is contemplated that the position of the sponsons 70 with respect to the hull 12 may be adjustable to change the handling characteristics of the watercraft 10 and accommodate different riding conditions. Trim tabs, which are commonly known, may also be provided at the transom and may be controlled from the helm 60 .
As best seen in FIGS. 3 and 4 , the helm assembly 60 is positioned forwardly of the seat 28 . The helm assembly 60 has a central helm portion 72 , that is padded, and a pair of steering handles 74 , also referred to as a handlebar. One of the steering handles 74 is provided with a throttle operator 76 , which allows the rider to control the engine 22 , and therefore the speed of the watercraft 10 . The throttle operator 76 can be in the form of a thumb-actuated throttle lever (as shown), a finger-actuated throttle lever, or a twist grip. The throttle operator 76 is movable between an idle position and multiple actuated positions. In a preferred embodiment, the throttle operator 76 is biased towards the idle position, such that, should the driver of the watercraft 10 let go of the throttle operator 76 , it will move to the idle position. The other of the steering handles 74 is provided with a reverse gate operator 77 used by the driver to actuate a reverse gate 110 of the watercraft 10 as described in greater detail below. The reverse gate operator 77 is a finger-actuated lever. However, it is contemplated that the reverse gate operator 77 could be a thumb-actuated lever or a twist grip.
As seen in FIG. 2 , a display area or cluster 78 is located forwardly of the helm assembly 60 . The display cluster 78 can be of any conventional display type, including a liquid crystal display (LCD), dials or LED (light emitting diodes). The central helm portion 72 has various buttons 80 , which could alternatively be in the form of levers or switches, that allow the driver to modify the display data or mode (speed, engine rpm, time . . . ) on the display cluster 78 or to change a condition of the watercraft 10 , such as trim (the pitch of the watercraft 10 ).
The helm assembly 60 is provided with a key receiving post 82 located near a center of the central helm portion 72 . The key receiving post 82 is adapted to receive a key (not shown) that starts the watercraft 10 . As is known, the key is typically attached to a safety lanyard (not shown). It should be noted that the key receiving post 82 may be placed in any suitable location on the watercraft 10 .
Returning to FIGS. 1 and 5 , the watercraft 10 is generally propelled by a jet propulsion system 84 . As is known, the jet propulsion system 84 pressurizes water to create thrust. The water is first scooped from under the hull 12 through an inlet 86 , which has an inlet grate (not shown in detail). The inlet grate prevents large rocks, weeds, and other debris from entering the jet propulsion system 84 , which may damage the system or negatively affect performance. Water flows from the inlet 86 through a water intake ramp 88 . The top portion 90 of the water intake ramp 88 is formed by the hull 12 , and a ride shoe (not shown in detail) forms its bottom portion 92 . Alternatively, the intake ramp 88 may be a single piece or an insert to which the jet propulsion system 84 attaches. In such cases, the intake ramp 88 and the jet propulsion system 84 are attached as a unit in a recess in the bottom of hull 12 .
From the intake ramp 88 , water enters a jet pump (not shown). The jet pump is located in a formation in the hull 12 , referred to as the tunnel 94 . The tunnel 94 is defined at the front, sides, and top by the hull 12 and is open at the transom 54 . The bottom of the tunnel 94 is closed by the ride plate 96 . The ride plate 96 creates a surface on which the watercraft 10 rides or planes at high speeds.
The jet pump includes an impeller (not shown) and a stator (not shown). The impeller is coupled to the engine 22 by one or more shafts 98 , such as a driveshaft and an impeller shaft. The rotation of the impeller pressurizes the water, which then moves over the stator that is made of a plurality of fixed stator blades (not shown). The role of the stator blades is to decrease the rotational motion of the water so that almost all the energy given to the water is used for thrust, as opposed to swirling the water. Once the water leaves the jet pump, it goes through a venturi 100 . Since the venturi's exit diameter is smaller than its entrance diameter, the water is accelerated further, thereby providing more thrust. A steering nozzle 102 is pivotally attached to the venturi 100 so as to pivot about a vertical axis 104 . The steering nozzle 102 could also be supported at the exit of the tunnel 94 in other ways without a direct connection to the venturi 100 . Moreover, the steering nozzle 102 can be replaced by a rudder or other diverting mechanism disposed at the exit of the tunnel 94 to selectively direct the thrust generated by the jet propulsion system 84 to effect turning.
The steering nozzle 102 is operatively connected to the helm assembly 60 preferably via a push-pull cable (not shown) such that when the helm assembly 60 is turned, the steering nozzle 102 pivots. This movement redirects the pressurized water coming from the venturi 100 , so as to redirect the thrust and steer the watercraft 10 in the desired direction. Optionally, the steering nozzle 102 may be gimbaled to allow it to move around a second horizontal pivot axis (as shown in FIGS. 8 and 9 ). The up and down movement of the steering nozzle 102 provided by this additional pivot axis is known as trim and controls the pitch of the watercraft 10 .
When the watercraft 10 is moving, its speed is measured by a speed sensor 106 attached to the transom 54 of the watercraft 10 . The speed sensor 106 has a paddle wheel 108 that is turned by the water flowing past the hull 12 . In operation, as the watercraft 10 goes faster, the paddle wheel 108 also turns faster. An electronic control unit (ECU) 200 ( FIG. 12 ) connected to the speed sensor 106 converts the rotational speed of the paddle wheel 108 to the speed of the watercraft 10 in kilometers or miles per hour, depending on the rider's preference. The speed sensor 106 may also be placed in the ride plate 96 or at any other suitable position. Other types of speed sensors, such as pitot tubes, and processing units could be used, as would be readily recognized by one of ordinary skill in the art. Alternatively, a global positioning system (GPS) unit could be used to determine the speed of the watercraft 10 by calculating the change in position of the watercraft 10 over a period of time based on information obtained from the GPS unit.
The watercraft 10 is provided with a reverse gate 110 which is movable between a first stowed position where it does not interfere with the jet of water (indicated by arrows 85 ) being expelled by the jet propulsion system 84 and a plurality of positions where it redirects the jet of water 85 being expelled by the jet propulsion system 84 . A reverse gate actuator (not shown) is operatively connected to the reverse gate 110 to move the reverse gate 110 . The reverse gate actuator could be any one of a mechanical, a hydraulic, or an electric actuator, such as an electric motor. One contemplated reverse gate actuator is shown and described in U.S. patent application Ser. No. 11/962,396, filed Dec. 21, 2007, the entirety of which is incorporated herein by reference. As seen in FIGS. 8 and 9 , it is contemplated that the reverse gate 110 could be mounted directly on the jet propulsion system 84 so as to move with the steering nozzle 102 as it turns and trims. Details of this arrangement can be found in U.S. Pat. No. 6,533,623 B2, issued Mar. 18, 2003, the entirety of which is incorporated herein by reference. In FIG. 8 , the reverse gate 110 is in a stowed position. In FIG. 9 , the reverse gate 110 is in a neutral position where it redirects the jet of water 85 downwardly. Since the thrust generated by the redirected jet of water 85 when the reverse gate 110 is in the neutral position does not have a horizontal component, the watercraft 10 will not be accelerated or decelerated by the thrust and will stay in position if it was not moving prior to moving the reverse gate 110 in the neutral position. As seen in FIGS. 10 and 11 , it is also contemplated that the reverse gate 110 could be pivotally attached to the sidewalls of the tunnel 94 . In FIG. 10 , the reverse gate 110 is in a stowed position. In FIG. 11 , the reverse gate 110 is in a reverse position as it redirects the jet of water 85 towards the front of the watercraft 10 , thus causing the watercraft 10 to move in a reverse direction. Other ways of operatively mounting the reverse gate 110 to the hull 12 are also contemplated. The operation of the reverse gate 110 is discussed in greater detail below.
The general construction of a sport boat 120 in accordance with this invention is shown in FIGS. 6 and 7 . The following description relates to one way of manufacturing a sport boat. Obviously, those of ordinary skill in the sport boat art will recognize that there are other known ways of manufacturing and designing sport boats and that this invention would encompass these other known ways and designs.
For simplicity, the components of the sport boat 120 which are similar in nature to the components of the personal watercraft 10 described above will be given the same reference numeral. It should be understood that their specific construction may vary however.
The sport boat 120 has a hull 12 and a deck 14 supported by the hull 12 . The deck 14 has a forward passenger area 122 and a rearward passenger area 124 . A right console 126 and a left console 128 are disposed on either side of the deck 14 between the two passenger areas 122 , 124 . A passageway 130 disposed between the two consoles 126 , 128 allows for communication between the two passenger areas 122 , 124 . A door 131 is used to selectively open and close the passageway 130 . At least one engine (not shown) is located between the hull 12 and the deck 14 at the back of the boat 120 . The engine powers the jet propulsion system (not shown) of the boat 120 . The jet propulsion system is of similar construction as the jet propulsion system 84 of the personal watercraft 10 described above, and will therefore not be described again. A reverse gate 110 is operatively mounted to the hull 12 . The reverse gate 110 is of similar construction as the reverse gate 110 of the personal watercraft 10 described above, and will therefore not be described again. In a preferred embodiment, the boat 120 has two engines and two jet propulsion systems each provided with a reverse gate 110 . The engine is accessible through an engine cover 132 located behind the rearward passenger area 124 . The engine cover 132 can also be used as a sundeck for a passenger of the boat 120 to sunbathe on while the boat 120 is not in operation. A reboarding platform 52 is located at the back of the deck 14 for passengers to easily reboard the boat 120 from the water.
The forward passenger area 122 has a C-shaped seating area 136 for passengers to sit on. The rearward passenger area 124 also has a C-shaped seating area 138 at the back thereof. A driver seat 140 facing the right console 126 and a passenger seat 142 facing the left console 124 are also disposed in the rearward passenger area 124 . It is contemplated that the driver and passenger seats 140 , 142 can swivel so that the passengers occupying these seats can socialize with passengers occupying the C-shaped seating area 138 . A windshield 139 is provided at least partially on the left and right consoles 124 , 126 and forwardly of the rearward passenger area 124 to shield the passengers sitting in that area from the wind when the boat 120 is in movement. The right and left consoles 126 , 128 extend inwardly from their respective side of the boat 120 . At least a portion of each of the right and the left consoles 126 , 128 is integrally formed with the deck 14 . The right console 126 has a recess 144 formed on the lower portion of the back thereof to accommodate the feet of the driver sitting in the driver seat 140 and an angled portion of the right console 126 acts as a footrest 146 . A reverse gate operator, in the form of a foot pedal 147 , is provided on the footrest 146 . It is contemplated that the foot pedal 147 could be replaced by a handle positioned near or on the steering wheel 148 . The function of the foot pedal 147 is similar to that of the reverse gate operator 77 of the personal watercraft 10 . As shown in FIGS. 13A to 13C , the foot pedal 147 is operatively connected to the reverse gate 110 . When the foot pedal 147 is not actuated, the reverse gate 110 is in the stowed position. When the foot pedal 147 is actuated, the reverse gate 110 moves to a position in which the jet of water 85 expelled by the jet propulsion system 84 is redirected as explained in greater detail below. FIG. 13A illustrates an embodiment where the foot pedal 147 is operatively connected to the reverse gate 110 via a mechanical actuator 220 . FIG. 13B illustrates an embodiment where the foot pedal 147 is operatively connected to the reverse gate 110 via a hydraulic actuator 222 . FIG. 13C illustrates an embodiment where the ECU 200 first receives a signal indicative of the position of the foot pedal 147 . The ECU 200 then sends a signal to an electric motor 224 to move the reverse gate 110 to a position based on the signal indicative of the position of the foot pedal 147 as described below. The left console 128 has a recess (not shown) similar to recess 144 to accommodate the feet of the passenger sitting in the passenger seat 142 . The right console 126 accommodates all of the elements necessary to the driver to operate the boat. These include, but are not limited to, a helm assembly in the form of the steering wheel 148 , a throttle operator 76 in the form of a throttle lever, and an instrument panel 152 . The instrument panel 152 have various dials indicating the watercraft speed, engine speed, fuel and oil level, and engine temperature. The speed of the boat 120 is measured by a speed sensor (not shown) which can be in the form of the speed sensor 106 described above with respect to the personal watercraft 10 or a GPS unit or any other type of speed sensor which could be used for marine applications. It is contemplated that the elements attached to the right console 126 could be different than those mentioned above. The left console 128 incorporates a storage compartment (not shown) which is accessible to the passenger sitting the passenger seat 142 .
Turning now to FIG. 12 , additional components of both the personal watercraft 10 and the sport boat 120 will be described. Although FIG. 12 illustrates a throttle operator 76 mounted to the handlebar like in the watercraft 10 , it should be understood that a throttle operator 76 of the type used in the sport boat 120 is contemplated. Similarly, although the reverse gate operator 77 is illustrated as being mounted to the handlebar, it is contemplated that a foot pedal, such as the foot pedal 147 of the sport boat 120 , could be used. In the personal watercraft 10 , the foot pedal could be located in one of the footrests 46 .
A throttle operator position sensor 202 senses a position of the throttle operator 76 and sends a signal representative of the throttle operator position to the ECU 200 . Depending on the type of throttle operator 76 , the throttle operator position sensor 202 is generally disposed in proximity to the throttle operator 76 and senses the movement of the throttle operator 76 or the linear displacement of a cable connected to the throttle operator 76 . The throttle operator position sensor 202 is preferably in the form of a magnetic position sensor. In this type of sensor, a magnet is mounted to the throttle operator 76 and a sensor chip is fixedly mounted in proximity to the magnet. As the magnet moves, due to movement of the throttle operator 76 , the magnetic field sensed by the sensor chip varies. The sensor chip transmits a voltage corresponding to the sensed magnetic field, which corresponds to the position of the throttle operator 76 , to the ECU 200 . It is contemplated that the sensor chip could be the one mounted to the throttle operator 76 and that the magnet could be fixedly mounted in proximity to the sensor chip. The throttle operator position sensor 202 could also be in the form of a rheostat. A rheostat is a resistor which regulates current by means of variable resistance. In this case, the position of the throttle operator 76 would determine the resistance in the rheostat which would result in a specific current being transmitted to the ECU 200 . Therefore, this current is representative of the position of the throttle operator 76 . It is contemplated that other types of sensors could be used as the throttle operator position sensor 202 , such as a potentiometer which regulates voltage instead of current.
Similarly, a reverse gate operator position sensor 204 senses a position of the reverse gate operator 77 (or foot pedal 147 ) and sends a signal representative of the reverse gate operator position to the ECU 200 . The reverse gate operator position sensor 204 can be of any of the types of sensors described above with respect to the throttle operator positions sensor 202 .
A steering position sensor 203 senses an angle by which the helm assembly is turned and sends a signal representative of that angle to the ECU 200 . The steering position sensor 203 can be of any type. Examples of such sensors are described in U.S. Pat. No. 6,428,371, issued Aug. 6, 2002, the entirety of which is incorporated herein by reference.
An engine speed sensor 206 senses a speed of rotation of the engine 22 and sends a signal representative of the speed of rotation of the engine 22 to the ECU 200 . Typically, an engine, such as engine 22 , has a toothed wheel disposed on and rotating with a shaft of the engine 22 , such as the crankshaft or output shaft. The engine speed sensor 206 is located in proximity to the toothed wheel and sends a signal to the ECU 200 each time a tooth passes in front it. The ECU 200 can then determine the engine rotation speed by calculating the time elapsed between each signal. The speed of rotation of the engine 22 can be used by the ECU 200 to calculate the engine torque.
A watercraft speed sensor 208 senses the speed of the watercraft and sends a signal representative of the speed of the watercraft to the ECU 200 . The ECU 200 sends a signal to a speed gauge located in the display cluster 78 ( FIG. 2 ) of the personal watercraft 10 or in the instrument panel 152 of the sport boat 120 such that the speed gauge displays the watercraft speed to the driver of the watercraft. The vehicle speed sensor 208 can be of any type, such as the speed sensor 106 or the GPS unit described above.
Depending on the operating condition of the watercraft, one or more of the signals received from the throttle operator position sensor 202 , the reverse gate operator position sensor 204 , the steering position sensor 203 , the engine speed sensor 206 , and the watercraft speed sensor 208 can be used by the ECU 200 to control the operation of the engine 22 . The ECU 200 controls the operation of the engine 22 , and therefore the speed of rotation of the engine 22 , by sending signals to a throttle valve actuator 210 , an ignition system 212 of the engine 22 , and an injection system 214 of the engine 22 . The throttle valve actuator 210 is preferably an electric motor, such as a servo motor. The throttle valve actuator 210 is connected to the valve 216 of the throttle body of the engine 22 . Based on the signal from the ECU 200 , the throttle valve actuator 210 changes a degree of opening of the throttle valve so as to control the flow of air to the engine 22 . A throttle valve position sensor (not shown) could be provided to send a feedback signal indicative of the position of the throttle valve 216 to the ECU 200 . The signal from the ECU 200 to the ignition system 212 controls the ignition timing. The signal(s) from the ECU 200 to the injection system 214 controls the injection timing and the quantity of fuel being injected per injection event. It is contemplated that the engine 22 may be provided with a carburetor instead of the throttle body and would therefore not require an injection system 214 . It is believed that the way in which the degree of opening of the throttle valve 216 , the ignition timing, the injection timing, and the quantity of fuel being injected affect the speed of rotation of the engine 22 are well understood by those skilled in the art of engines and will therefore not be described.
As would also be understood by those skilled in the art of jet propelled watercraft, increasing or decreasing the speed of rotation of the engine 22 results in an increase or decrease, respectively, in the thrust generated by the jet propulsion system 84 . However, it is contemplated that the thrust generated by the jet propulsion system could otherwise be controlled. For example, the diameter of a portion of the jet propulsion system 84 , such as the venturi 110 or steering nozzle 102 , could be varied. U.S. Pat. No. 6,857,918, issued Feb. 22, 2005, the entirety of which is incorporated herein by reference, discloses various variable venturies to be used in a jet propulsion system.
The ECU 200 also sends a signal to a reverse gate actuator 218 to move the reverse gate 110 between a stowed position ( FIGS. 8 and 10 ) and a position in which the reverse gate 110 redirects the jet of water 85 expelled from the jet propulsion system 84 ( FIGS. 9 and 11 ), as will be described in greater detail below. The reverse gate actuator 218 can be in the form of an electric actuator, an hydraulic actuator, or any other type of actuator suitable for moving the reverse gate 110 and maintaining it in position.
Turning now to FIGS. 14 to 16 , methods of controlling a watercraft, methods 300 , 400 , and 500 respectively, will be described. For simplicity, the methods 300 , 400 , and 500 will be explained with respect to the personal watercraft 10 , but it should be understood that the same or similar methods could be used with the sport boat 120 . Many of the steps of the methods 300 , 400 , and 500 described below involve the ECU 200 . It is contemplated that electronic modules other than the ECU 200 could be involved in these steps instead of the ECU 200 . However, for purposes of this application, these other electronic modules would be considered to be part of the ECU 200 . Also, in the embodiments described below, the thrust generated by the jet propulsion unit 84 is controlled by controlling a speed of rotation of the engine 22 , but it is contemplated that the thrust generated could be controlled otherwise, as previously mentioned. Finally, in the embodiments described below, the speed of rotation of the engine 22 is controlled by moving the throttle valve 216 by having the ECU 200 send a signal to the throttle valve actuator 210 . However it is contemplated that the speed of rotation of the engine 22 could be controlled by having the ECU 200 send a signal to the ignition system 212 and/or the injection system 214 alone or in combination with the signal sent to the throttle valve actuator 210 .
Turning now to FIG. 14 , the method 300 is initiated at step 302 . Then at step 304 , the reverse gate operator position sensor 204 senses the position of the reverse gate operator 77 and sends a signal representative of this position to the ECU 200 . At step 306 , the ECU 200 determines if the reverse gate operator 77 is actuated.
If at step 306 it is determined that the reverse gate operator 77 is not actuated, then at step 308 the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the stowed position (unless the reverse gate 110 is already in the stowed position). Then at step 310 , the throttle operator position sensor 202 senses the position of the throttle operator 76 and sends a signal representative of this position to the ECU 200 . Once it receives the signal indicative of the position of the throttle operator 76 , at step 312 the ECU 200 sends a signal to the throttle valve actuator 210 to control the speed of rotation of the engine 22 based at least on the position of the throttle operator 76 sensed at step 310 . From step 312 , the method 300 resumes at step 304 .
If at step 306 it is determined that the reverse gate operator 77 is actuated, then at step 314 the watercraft speed sensor 208 senses a speed of the watercraft 10 and sends a signal representative of this speed to the ECU 200 . Then at step 316 , the ECU 200 determines if the speed sensed at step 314 is greater than a predetermined watercraft speed V 1 . The predetermined watercraft speed V 1 is a speed of the watercraft 10 above which generating too much thrust with the jet propulsion system 84 while the reverse gate 110 is in a position in which it redirects the jet of water being expelled by the jet propulsion system 84 could result in the stern of the watercraft 10 lifting and the bow 56 of the watercraft 10 dipping. It is contemplated that the predetermined watercraft speed V 1 could be a speed above which the ECU 200 enters a controlled deceleration mode (steps 320 to 342 described below) to slow down the watercraft 10 and at, or below which the ECU 200 enters a reverse mode (steps 310 , 312 , and 318 ) to reverse the direction of travel of the watercraft 10 (or keep it in position). In either case, the predetermined watercraft speed V 1 will vary from one type of watercraft to the other. It is contemplated that at step 316 , the ECU 200 could determine if the speed sensed at step 314 is greater than or equal to the predetermined watercraft speed V 1 . It is also contemplated that the predetermined watercraft speed V 1 could be a speed of the watercraft 10 slightly below the speed above which generating too much thrust could result in the stern of the watercraft 10 lifting and the bow 56 of the watercraft 10 dipping.
If at step 316 it is determined that the speed of the watercraft 10 is less than or equal to the predetermined watercraft speed V 1 , then at step 318 the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to a position in which it redirects the jet of water being expelled by the jet propulsion system 84 . The position to which the reverse gate 110 is moved is based on the position of the reverse gate operator 77 sensed at step 304 . In a preferred embodiment, for step 318 , each position of the reverse gate operator 77 has a corresponding position of the reverse gate 110 . However it is contemplated that inputs from other sensors could be taken into account by the ECU 200 in addition to the position of the reverse gate operator 77 to determine the position to which the reverse gate 110 should be moved. From step 318 , the method 300 goes step 310 and continues to step 312 . At step 312 , the ECU 200 sends a signal to the throttle valve actuator 210 to control the speed of rotation of the engine 22 based at least on the position of the throttle operator 76 sensed at step 310 and the position of the reverse gate operator 77 sensed at step 304 . In an alternative embodiment, shown with the dashed line, from step 318 , the method 318 goes to step 312 , and at step 312 the ECU 200 sends a signal to the throttle valve actuator 210 to control the speed of rotation of the engine 22 based on the position of the reverse gate operator 77 sensed at step 304 , independently of the position of the throttle operator 76 .
If at step 316 it is determined that the speed of the watercraft 10 is greater than the predetermined watercraft speed V 1 , the ECU 200 enters a controlled deceleration mode, then at step 320 the engine speed sensor 208 senses a speed of rotation of the engine 22 and sends a signal representative of this speed to the ECU 200 . Then at step 322 , the ECU 200 determines if the speed of rotation of the engine 22 is greater than a reverse gate actuation speed RPM 1 . The reverse gate actuation speed RPM 1 is a speed of rotation of the engine 22 above which the resulting thrust generated by the jet propulsion system 84 would be too high to lower the reverse gate 110 (i.e. attempting to do so would make the reverse gate 110 either go back to the stowed position due to the thrust or the handling of the watercraft could be compromised). The reverse gate actuation speed RPM 1 will vary from one type of watercraft to the other as it is dependent on the features of the jet propulsion system (dimensions, impeller and stator shape and size) as well as the geometry and size of the reverse gate 110 .
If at step 322 it is determined that the speed of rotation of the engine 22 sensed at step 320 is greater than the reverse gate actuation speed RPM 1 , then at step 324 the ECU 200 sends a signal to the throttle valve actuator 210 to move the throttle valve 216 in order to reduce a degree of opening of the throttle valve 216 so as to reduce the speed of rotation of the engine 22 . From step 324 , the method returns to step 320 and steps 320 to 324 are repeated until the speed of rotation of the engine 22 is at or less than the reverse gate actuation speed RPM 1 .
If at step 322 it is determined that the speed of rotation of the engine 22 sensed at step 320 is at or less than the reverse gate actuation speed RPM 1 , then at step 326 the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate to a position in which the reverse gate 110 redirects the jet of water 85 being expelled from the jet propulsion system 84 at least in part towards the front of the watercraft, as shown in FIG. 11 . The position to which the reverse gate 110 is moved is preferably independent of the position of the reverse gate operator 77 sensed at step 304 as doing so could, in some cases result in too much reverse thrust being generated and/or could damage the reverse gate 110 . The position to which the reverse gate 110 is moved is determined based on other inputs to the ECU 200 such as the speed of the watercraft 10 sensed at step 314 and/or the speed of rotation of the engine 22 sensed at step 320 . It is contemplated that the ECU 200 could send a signal to the reverse gate actuator 218 to continuously adjust the position of the reverse gate 110 as the watercraft 10 decelerates and the speed of rotation of the engine 22 varies. It is also contemplated that the position to which the reverse gate 110 is moved could be based at least in part on the position of the reverse gate operator 77 sensed at step 304 for at least a range of positions of the reverse gate operator 77 . It is also contemplated that the position to which the reverse gate 110 is moved could be a predetermined position, such as the fully lowered position of the reverse gate 110 , independent of the position of the reverse gate operator 77 .
From step 326 , the method continues to step 328 where the ECU 200 sends a signal to the throttle valve actuator 210 to move the throttle valve 216 in order to increase a degree of opening of the throttle valve 216 so as to increase the speed of rotation of the engine 22 . Then at step 330 , the engine speed sensor 208 senses a speed of rotation of the engine 22 and sends a signal representative of this speed to the ECU 200 . Then at step 332 , the ECU 200 determines if the speed of rotation of the engine 22 is greater than the reverse gate actuation speed RPM 1 . If the speed of rotation of the engine 22 is not greater than the reverse gate actuation speed RPM 1 , then from step 332 , the method returns to step 328 and steps 328 to 332 are repeated until the speed of rotation of the engine 22 is greater than the reverse gate actuation speed RPM 1 . If at step 332 it is determined that the speed of rotation of the engine 22 is greater than the reverse gate actuation speed RPM 1 , the method 300 continues to step 334 . It is contemplated that steps 328 to 332 could be omitted and that the ECU 200 could go directly from step 326 to step 334 .
At step 334 , the ECU 200 sends a signal to the throttle valve actuator 210 in order to control the speed of rotation of the engine 22 such that the thrust generated by the redirected water jet 85 results in a controlled deceleration of the watercraft 10 . The speed of rotation of the engine 22 is adjusted throughout the controlled deceleration. It is contemplated that at step 334 the speed of rotation of the engine 22 could be controlled so as to provide thrust in bursts. The controlled deceleration continues until either the watercraft 10 is moving at or below a predetermined watercraft speed V 2 or the reverse gate operator 77 is no longer being actuated as described below with respect to steps 336 to 344 . The signal sent by the ECU 200 at step 334 is preferably determined independently of the position of the throttle operator 76 , since adjusting the position of the throttle valve 216 based on the position of the throttle operator 76 might not result in the desired controlled deceleration. However, it is contemplated that the signal sent by the ECU 200 at step 334 could be based in part on the position of the throttle operator 76 . For example, the rate of deceleration of the watercraft 10 could be increased or decreased based on the position of the throttle operator 76 . The signal sent by the ECU 200 at step 334 is preferably based on the speed of the watercraft 10 sensed at step 314 and the position of the reverse gate operator 77 sensed at step 304 . It is contemplated that the signal sent by the ECU 200 at step 334 could also be based at least in part on engine speed. It is contemplated that an accelerometer (not shown) could be used instead of or in addition to the watercraft speed sensor 208 to provide a signal to the ECU 200 to control the speed of rotation of the engine 22 so as to obtain a controlled deceleration. It is contemplated that other inputs to the ECU 200 could also be used.
From step 334 , the method 300 goes to step 336 where the watercraft speed sensor 208 senses a speed of the watercraft 10 and sends a signal representative of this speed to the ECU 200 . Then at step 338 , the ECU 200 determines if the speed sensed at step 336 is less than or equal to a predetermined watercraft speed V 2 . The predetermined watercraft speed V 2 is a low watercraft speed. It is contemplated that the predetermined watercraft speed V 2 could be 0 km/h. If at step 338 the speed of the watercraft 10 sensed at step 336 is less than or equal to the predetermined watercraft speed V 2 , then the method 300 goes to step 344 described below. If at step 338 the speed of the watercraft 10 sensed at step 336 is greater than the predetermined watercraft speed V 2 , then at step 340 the reverse gate operator position sensor 204 senses the position of the reverse gate operator 77 and sends a signal representative of this position to the ECU 200 . At step 342 , the ECU 200 determines if the reverse gate operator 77 is actuated. If at step 342 it is determined that the reverse gate operator 77 is not actuated, then the method 300 goes to step 344 described below. If at step 342 it is determined that the reverse gate operator 77 is actuated, then the method 300 returns to step 334 . Note that when step 334 is being carried out following step 342 , it is the speed of the watercraft 10 sensed at step 336 and the position of the reverse gate operator 77 sensed at step 340 that are used by the ECU 200 to determine the signal sent to the throttle valve actuator 210 . In one embodiment, as the speed of the watercraft 10 decreases, the speed of rotation of the engine 22 is increased at step 334 . Also, if the position of the reverse gate operator 77 has increased or decreased at step 340 (i.e. more or less deceleration is desired), then the level of increase of the speed of rotation of the engine 22 at step 334 is adjusted accordingly.
At step 344 , the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position. From step 344 , the method resumes at step 304 . It is contemplated that step 344 could be omitted, and that the method 300 could go directly from steps 338 and 342 to step 304 . It is also contemplated that step 344 could be replaced by a step where the ECU 200 could send a signal to the reverse gate actuator 218 to move the reverse gate 110 to the stowed position instead of the neutral position.
It is contemplated that the reverse gate 110 could be actuated directly by the reverse gate operator 77 (i.e. the reverse gate actuator 210 would not be actuated as a result of a signal sent by the ECU 200 ). As a result, the reverse gate 110 would move to a position other than the stowed position directly as a result of the reverse gate operator 77 being actuated. Therefore, in such a case, some of the steps of the method 300 would be omitted or modified accordingly. However, the modified method would still result the thrust being generated by the jet propulsion assembly 84 to be controlled independently of the position of the throttle operator 76 when the reverse gate actuator 77 is actuated and the watercraft 10 is moving at a speed greater than the predetermined watercraft speed V 1 .
In the method 300 , it is contemplated that when the speed of the watercraft 10 is less than or equal to the predetermined watercraft speed V 1 and the reverse gate 110 has been moved as a result of step 318 , that the maximum speed of rotation of the engine 22 could be limited to a first predetermined maximum engine speed at step 312 , and that when the speed of the watercraft 10 is greater than the predetermined watercraft speed V 1 and the reverse gate 110 has been moved as a result of step 326 , that the maximum speed of rotation of the engine 22 could be limited to a second predetermined maximum engine speed at step 334 . The second predetermined maximum engine speed being less than the first predetermined engine speed in order to prevent the watercraft 10 from pitching forward at high watercraft speed. It is contemplated that the second predetermined maximum engine speed could be variable, such that as the speed of the watercraft 10 decreases, the second predetermined maximum engine speed increases. It is also contemplated that in such an embodiment, the signal sent by the ECU 200 to the throttle valve actuator 210 at steps 312 and 334 could be either at least in part or fully independent of the position of the throttle operator 76 as described above, or based on the position of the throttle operator 76 . It is also contemplated that instead of controlling the engine 22 so as not to exceed a first and a second predetermined maximum engine speed, that the ECU 200 could control the engine 22 (and jet propulsion system 84 if applicable) so a not to exceed a first and second predetermined maximum thrust generated by the jet propulsion system 84 . The second predetermined maximum thrust being less than the first predetermined maximum thrust.
Turning now to FIG. 15 , the method 400 is initiated at step 402 . Then at step 404 , the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position. By moving the reverse gate 110 to the neutral position upon initiating the method 400 , the personal watercraft 10 will not be accelerated forwardly or rearwardly by the thrust generated by the engine 22 when it is started. Then at step 406 , the reverse gate operator position sensor 204 senses the position of the reverse gate operator 77 and sends a signal representative of this position to the ECU 200 . At step 408 , the ECU 200 determines if the reverse gate operator 77 is actuated.
If at step 408 it is determined that the reverse gate operator 77 is actuated, then the method 400 proceeds as in the method 300 (i.e. goes to step 314 and then to steps 316 to 344 ). For simplicity, these steps have not been reproduced in FIG. 15 and will not be described again. Note that in the method 400 , step 344 returns to step 406 , instead of step 304 as in the method 300 . Also note that in the method 400 , the step 318 goes to step 412 described below, instead of step 310 as in the method 300 .
If at step 408 it is determined that the reverse gate operator 77 is not actuated, then at step 410 the ECU 200 determines if the reverse gate 110 is stowed based on the signal received from a reverse gate position sensor (not shown) or a feedback signal from the reverse gate actuator 218 .
If at step 410 it is determined that the reverse gate 110 is stowed, then the ECU 200 proceeds to step 412 . At step 412 , the throttle operator position sensor 202 senses the position of the throttle operator 76 and sends a signal representative of this position to the ECU 200 . Once it receives the signal indicative of the position of the throttle operator 76 , at step 414 the ECU 200 sends a signal to the throttle valve actuator 210 to control the speed of rotation of the engine 22 based at least on the position of the throttle operator 76 sensed at step 412 . From step 414 , the method 400 returns to step 406 .
If at step 410 it is determined that the reverse gate 110 is not in the stowed position, then the ECU 200 proceeds to step 416 . At step 416 , the ECU 200 determines if the throttle operator 76 was engaged when the engine 22 was started based on the signal received from the throttle operator position sensor 202 when the engine 22 was started. If the throttle operator 76 was not engaged when the engine 22 was started, then the ECU 200 proceeds to step 422 . If at step 416 it is determined that the throttle operator 76 was engaged when the engine 22 was started, then at step 418 the ECU 200 determines if the throttle operator 76 has been returned to its idle position since the engine 22 was started based on the signals received from the throttle operator position sensor 202 since the engine 22 was started. If the throttle operator 76 has not been returned to its idle position since the engine 22 was started, then at step 420 the throttle operator position sensor 202 senses the position of the throttle operator 76 and the ECU 200 returns to step 418 to determine if the throttle operator 76 has now been returned to its idle position. Steps 418 and 420 are repeated until the throttle operator 76 is returned to its idle position. If at step 420 the position of the throttle operator 76 sensed by the throttle operator position sensor 202 is the idle position, then from step 418 the ECU proceeds to step 422 . If at step 418 it is determined that the throttle operator 76 has been returned to its idle position since the engine 22 was started, then the ECU 200 proceeds to step 422 . Steps 416 to 420 prevent a sudden amount of thrust to be generated by the jet propulsion system 84 at engine start-up. In the method 400 , at engine start-up, since the reverse gate 110 is in the neutral position as a result of step 404 , applying a sudden amount of thrust could cause the transom 54 to lift, thus possibly causing a driver of the personal watercraft 10 to lose his balance.
At step 422 the throttle operator position sensor 202 senses the position of the throttle operator 76 and the ECU 200 then proceeds to step 424 . At step 424 , the ECU 200 determines if a rate of change in the position of the throttle operator 76 is greater than a predetermined amount X. If the rate of change in the position of the throttle operator 76 is greater than the predetermined amount X, then the ECU 200 returns to step 422 and steps 424 and 422 are repeated until the rate of change in the position of the throttle operator 76 is not greater than the predetermined amount X. If at step 424 the rate of change in the position of the throttle operator 76 is not greater than the predetermined amount X, then the ECU 200 proceeds to step 428 .
In an alternative embodiment shown in dashed lines, from step 422 the ECU 200 proceeds to step 426 . At step 426 , the ECU 200 determines if the position of the throttle operator 76 is greater than a predetermined amount Y. If the position of the throttle operator 76 is greater than the predetermined amount Y, then the ECU 200 returns to step 422 and steps 426 and 422 are repeated until the position of the throttle operator 76 is not greater than the predetermined amount Y. If at step 426 the position of the throttle operator 76 is not greater than the predetermined amount Y, then the ECU 200 proceeds to step 428 .
Both steps 424 and 426 prevent a sudden amount of thrust to be generated by the jet propulsion system 84 when the reverse gate operator 77 is not actuated (step 408 ) and the reverse gate 110 is not in the stowed position (step 410 ), thus preventing the aforementioned problem of the transom 54 possibly lifting.
At step 428 , the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the stowed position and then proceeds to step 412 (thus allowing the watercraft 10 to accelerate).
Turning now to FIG. 16 , the method 500 will be described. It is contemplated that the method 500 could be carried out at the same time as the method 300 or 400 . The method 500 is initiated at step 502 . Then at step 504 , the ECU 200 determines if the engine 22 is being started. If the engine 22 is being started, then at step 506 the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position (unless the reverse gate 110 is already in the neutral position). The ECU 200 then proceeds to step 508 . If at step 504 , the ECU 200 determines that the engine 22 is not being started (i.e. the engine 22 is already running or is stopped), then the ECU proceeds to step 508 .
At step 508 , the ECU 200 determines if the engine 22 is being stopped. If the engine 22 is stopped, then at step 510 the ECU 200 sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position (unless the reverse gate 110 is already in the neutral position). The ECU 200 then returns to step 504 . If at step 508 , the ECU 200 determines that the engine 22 is not stopped, then the ECU proceeds to step 512 .
At step 512 the throttle operator position sensor 202 senses the position of the throttle operator 76 and the ECU 200 then proceeds to step 514 . At step 514 , the ECU 200 determines if the throttle operator 76 is in the idle position. If the throttle operator 76 is not in the idle position, the ECU 200 returns to step 508 . If the throttle operator 76 is in the idle position, then at step 516 the ECU 200 determines if the throttle operator has been in the idle position for longer than a predetermined time t 1 . For example, the time t 1 could be 10 minutes. If the throttle operator 76 has been in the idle position for longer than the predetermined time t 1 , then the ECU 200 returns to step 506 and sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position (unless the reverse gate 110 is already in the neutral position). If at step 516 it is determined that the throttle operator 76 has not been in the idle position for longer than the predetermined time t 1 , then the ECU 200 proceeds to step 518 .
At step 518 , the reverse gate operator position sensor 204 senses the position of the reverse gate operator 77 and sends a signal representative of this position to the ECU 200 . Then at step 520 , the ECU 200 determines if the reverse gate operator 77 has been actuated for less than a predetermined amount of time t 2 before being released. In one exemplary embodiment, the predetermined amount of time t 2 corresponds to an amount of time it takes a user of the watercraft 10 to actuate and then almost immediately release the reverse gate operator 77 . For example, the time t 2 could be half a second. If the reverse gate operator 77 has not been actuated for less than the predetermined amount of time t 2 before being released, then the ECU 200 returns to step 508 . If at step 520 , it is determined that reverse gate operator 77 has been actuated for less than a predetermined amount of time t 2 before being released, then the ECU 200 returns to step 506 and sends a signal to the reverse gate actuator 218 to move the reverse gate 110 to the neutral position (unless the reverse gate 110 is already in the neutral position).
Modifications and improvements to the above-described embodiments of the present invention may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present invention is therefore intended to be limited solely by the scope of the appended claims.
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A method of controlling a watercraft is disclosed which comprises actuating a reverse gate operator, sensing a speed of the watercraft, controlling a thrust generated by a jet propulsion system differently depending on whether the speed of the watercraft is above or below a predetermine watercraft speed when the reverse gate operator is actuated, and moving the reverse gate to a position in which the reverse gate redirects a jet of water expelled from the jet propulsion system in response to the actuation of the reverse gate operator. A watercraft implementing the above method is also disclosed.
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FIELD OF THE INVENTION
The present invention relates to a control device and a related method thereof for a passenger protection arrangement for a vehicle.
BACKGROUND INFORMATION
German patent document DE 102 52 227 A1 refers to a sensor system for detecting an accident signal can be oriented in different spatial directions.
SUMMARY OF THE INVENTION
In contrast, the control device and the method according to the present invention for triggering a passenger protection arrangement for a vehicle having the features of the independent claims have the advantage that in the case of a coordinate system oriented in relation to the vehicle longitudinal direction having acceleration sensors disposed at an angle with regard to their sensitivity axes, both the acceleration signals oriented in this angle and the transformed acceleration signals on the coordinate system are used immediately. It is thus possible to better detect angled impact situations, so-called angle crashes. More information about an impact is used. The improved angle crash detection has the advantage that in the event of crashes against a hard barrier at speeds between 25 and 30 km/h the passenger protection arrangement is precisely triggered, since angle crashes are better detected in accordance with the exemplary embodiments and/or exemplary methods of the present invention, and thus in the event of so-called low-risk crashes such triggerings must be prevented in advance. That is, in the event of such angle crashes, a triggering is not permitted to occur. Furthermore, the exemplary embodiments and/or exemplary methods of the present invention has the advantage that it allows for so-called non-triggering crashes and triggering angle crashes to be differentiated in an improved manner.
An additional great advantage is that essential information may be obtained for the crashes occurring in the field. For example, soft crashes from the side may be detected only with difficulty. These collisions result in a yaw acceleration that may be detected in the control device and used for the triggering decision. The invention provided supplies valuable supplementary information for such a yaw acceleration algorithm, for example, for plausibilization.
In the case at hand, a control device is an electrical device that processes sensor signals and generates triggering signals for the passenger protection arrangement such as airbags, belt tighteners, crash-active headrests, etc., as a function thereof. Triggering means the activation of such a passenger protection arrangement.
An interface is predominantly developed as hardware and/or software. In a hardware design, a development of the interfaces on a system ASIC is possible, in particular. That is, the interface is part of an integrated circuit having a plurality of sections that fulfill different functions for the control device. However, alternatively it is possible that the interface has its own integrated circuit or is part of a processor or, in the software development, is a software module on such a processor.
The acceleration signals may have all possible forms, in particular, a preprocessing such as a smoothing, filtering, integration, etc., may be performed. The acceleration sensors may be disposed in all possible locations on the vehicle. This includes a central placement, for example, in a sensor control device, but also a decentralized placement in the region of the vehicle sides, for example. The acceleration sensors are normally produced micromechanically, it being possible to use a surface micromechanical technique for the production, in particular. In this context, a change in capacitance is converted into a voltage change. The angled placement is, for example, characterized in that in the horizontal plane of the vehicle, it is offset from the vehicle longitudinal axis by 45° in each instance. However, every other angled placement is also possible, in particular, also a 45° placement, in relation to the vehicle transverse axis, of the two acceleration sensors respectively.
The evaluation circuit is designed as hardware and/or software, it also being possible for an integration to be provided as a processor having corresponding software or as an implementation of the functions of the evaluation circuit in hardware as a so-called ASIC. All possible processor types are provided as processors, in particular dual core processors and also in particular microcontrollers. The transformer module and the comparison module may also be designed as hardware and/or software; in particular, a development in software modules may be provided. The transformer module implements the function of transforming the acceleration signals from the angled placement into acceleration signals that are respectively oriented toward axes of the coordinate system. This may occur through a corresponding vector analysis of the components, in the vehicle longitudinal direction and the vehicle transverse direction, for example. The comparison module has the task of comparing the acceleration signals and the transformed accelerations signals. This comparison may take place with the aid of the preprocessed acceleration signals but also with the aid of further processed acceleration signals, for example with the aid of integrations, derivations, etc.
The triggering circuit may be implemented in hardware and/or software as well. In particular, in a hardware design, this triggering circuit may also be part of the system ASIC. In this context, the triggering circuit contains the corresponding logic in order to process the triggering signals, and the power switches in order to direct the corresponding triggering energy to the passenger protection arrangement. This triggering energy is stored, for example, in an energy reserve, for example, in a capacitor, and is then conducted through to an ignition element of an airbag, for example, by electrically controllable power switches. The triggering signal may be made up of one signal or a plurality of signals that are also transmitted in parallel. In this context, a higher redundancy and thus security is achieved.
The measures and further refinements described in the dependent claims permit advantageous improvements to the control device and method, respectively, set forth in the independent patent claims for triggering a passenger protection arrangement for a vehicle.
In this context, it is advantageous that the comparison module for determining a crash type is provided as a function of a comparison and generates the triggering signal as a function of the crash type. The comparison module is able to identify the angle crash, in particular. As described above, this allows for an improved processing of the accident signals and helps to better differentiate crash types.
Furthermore, it is advantageous that the comparison module supplies the crash type to a main algorithm, the main algorithm influencing at least one threshold as a function of the crash type. Thus, the crash type ascertained by the comparison module is used to influence the triggering decision made by the main algorithm. If the threshold is lowered, the main algorithm becomes more sensitive and thus triggers the passenger protection arrangement earlier than is provided in the basic setting. A classification in a corresponding classification algorithm may also be accordingly influenced.
In this context, it is furthermore advantageous that the comparison module is connected to a yaw acceleration algorithm in such a manner that a result of the yaw acceleration algorithm is plausibilized with the aid of the crash type. As described above, a yaw acceleration may be evaluated and this result may then be plausibilized using the control device and method according to the present invention.
It is furthermore advantageous that the comparison module is connected to a second interface and the crash type is made available to an additional control device via the second interface. In this context, the second interface may be a bus transceiver such as a CAN transceiver, for example, but also a point-to-point connection. The interface may be designed as hardware and/or software, in particular. Thus the crash type may also be provided to other control devices, such as a control device for influencing the driving dynamics, in order to achieve a better stabilization of the vehicle in the event of a multiple crash, for example.
It is furthermore advantageous that the comparison module has a first threshold value decider that compares one of the transformed acceleration signals to a predetermined threshold value. It is advantageous that the comparison module has a second threshold value decider that compares a signal derived from the one of the transformed acceleration signals to one of the at least two acceleration signals, that a logic element links together output signals of the two threshold value deciders, and that the comparison module sets at least one flag as a function of the link, the comparison module generating the triggering signal as a function of the at least one flag. In this context, the threshold value deciders, the logic element, are designed as hardware and/or software. The first threshold value decider checks whether the transformed, signal exceeds a predetermined variable at all, and performs the further processing only when this is the case. Otherwise, the impact is too small to implement an additional classification. The second threshold value decider then ultimately compares the transformed acceleration signal and the original acceleration signal, respectively. The logic element, for example, a logical AND gate, links the output signals of the two threshold value deciders in order to set a flag as a function thereof. The flag indicates, for example, which angle crash is identified and the triggering signal may then be generated as a function of this flag. In the case at hand, generate also means influencing how the triggering signal is generated.
It is furthermore advantageous that the flag indicates an angle crash, to wit a predetermined angle crash.
Exemplary embodiments of the present invention are illustrated in the drawing and are explained in greater detail in the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a first placement of the acceleration sensors in the control device in the vehicle.
FIG. 2 shows the signals that are measured and are to be processed.
FIG. 3 shows a block diagram to elucidate the function according to the present invention.
FIG. 4 shows another block diagram to elucidate the sequence of the method according to the present invention.
FIG. 5 shows a flow chart illustrating the method according to the present invention.
FIG. 6 shows an additional block diagram to elucidate the method according to the present invention.
FIG. 7 shows a block diagram of the control device according to the present invention.
DETAILED DESCRIPTION
FIG. 7 shows in a block diagram control device SG according to the present invention. The signals CH 1 and CH 2 , which are the respectively measured acceleration signals in the angled placement, are transmitted by the acceleration sensor system to interface IF 1 . In the case at hand, the acceleration sensor system is disposed outside of control device SG. Interface IF 1 , which, as specified above, may be part of a system ASIC, for example, transmits signals CH 1 and CH 2 , via the SPI bus, for example, to microcontroller μC for further processing. As a software module, microcontroller μC has transformer module T, which generates from signals CH 1 and CH 2 the signals in the coordinate system of the vehicle, namely in relation to the vehicle longitudinal direction and the vehicle transverse direction. Transformer module T then transmits these transformed acceleration signals and the measured acceleration signals, also preprocessed, to comparison module V. Comparison module V compares signals CH 1 and CH 2 to the transformed signals, respectively, in order to recognize whether it is an angle crash or not. In this context, an angle crash is determined if one of signals CH 1 and CH 2 is greater than the respectively transformed signal. This angle crash information is then supplied for one to a main algorithm A, which generates the triggering signal as a function thereof. Furthermore, this angle crash information, for example, via a flag, is also set via an additional interface IF 2 to a bus 700 , so that other control devices such as the driving dynamics control device may also receive this information and in a multiple crash may also in this way have a stabilizing effect on the vehicle.
The triggering signal is then transmitted by microcontroller μC via module A to triggering circuit FLIC, which triggers electrically controllable power switches as a function of the triggering signal, in order to supply the corresponding triggering energy to a corresponding passenger protection arrangement PS. Corresponding passenger, protection arrangement PS is thus triggered.
FIG. 1 illustrates in a basic representation a placement of the acceleration sensors in control device ECU, in the case at hand the acceleration sensors being labeled with signal names. CH 1 and CH 2 . In the case at hand, the acceleration sensors are oriented at a 45° angle to the vehicle transverse direction. It is thus possible to detect angle crashes FL and SLB, for example. Angle crash FL stands for front left, and angle crash SLB for side left back. The vehicle longitudinal direction is labeled by x. In the case at hand, the vehicle is considered from below.
FIG. 2 illustrates in principle first the measured variables CH 1 and CH 2 , which are oriented at an angle to the vehicle transverse direction, like in FIG. 1 , and the signals to be processed therefrom, to wit, the measuring signals themselves, CH 1 and CH 2 , as well as the transformed acceleration signals Ecux and Ecuy. This is valid in the case, as shown in FIG. 7 , that the acceleration sensor system is disposed outside of the control device or, as shown in FIG. 1 , that it is disposed inside of control device ECU.
FIG. 3 shows in principle the incoming signals, to wit, the signals CH 1 , CH 2 , Ecux, and Ecuy, that enter into the function for the detection of angle crashes 300 . For example, the signals Wfr, Wfl, WSlb, WSrf can be generated therefrom. In this context, Wfr means an angle crash front right, Wfl an angle crash front left, WSlb an angle crash side left back, and WSrf an angle crash side right front. Additional angle crashes may be identified accordingly. Function 300 is normally implemented on microcontroller μC.
FIG. 4 shows a block diagram for illustrating what may occur in comparison module V for a placement according to FIG. 1 . Placement 400 illustrates an angled sensor system relative to the vehicle longitudinal axis. Signal 20 transformed to the vehicle longitudinal direction is compared to a predefined threshold value Min_Thd 10 in threshold value decider 401 . In this context, the threshold value is selected such that signal 20 has to reach a specific level in order to enable the further processing at all. In block 30 , signal 20 is used to set an application parameter that causes a flag for an angle crash front left to be set if an angle crash is detected in the case at hand. Signal EcuX, scaled by a factor 30 , is then compared to signal 40 , that is, signal CH 1 , in threshold value decider 402 . Only if signal 20 , scaled by a factor 30 , is smaller than signal 40 , and signal 20 has exceeded threshold value Min_Thd 10 , will logic element 403 , in the case at hand a logical AND operation, set flag 404 for the angle crash front left.
FIG. 5 shows a flow chart of the method according to the present invention. The measured acceleration sensor values CH 1 and CH 2 enter into method step 01 , in that these measuring values are transformed on the coordinate system in the vehicle, as described above. The transformed signals and also measuring signals CH 1 and CH 2 enter in method step 02 . In method step 02 , characteristics are generated that may be generated through a temporal integration, a window integration, a high-pass filtering or in another way, for example.
In method step 03 , a threshold value comparison occurs, as may be seen in FIG. 4 or also in FIG. 6 , for example. The corresponding angle crashes may then, be detected on this basis. The information about the crash type may be used in subsequent algorithm parts, for example in an influencing module for the main algorithm threshold (method step 04 ) or in the plausibilization of a yaw acceleration algorithm (method step 05 ) or in the transmission of this crash type information to an additional control device (method step 06 ).
FIG. 6 illustrates an additional block diagram, now for another placement of the acceleration sensors, to wit, in an angled placement in relation to the vehicle longitudinal axis. This is represented by block 600 . In the case at hand, the structure of the signal processing is identical to that in FIG. 4 . In turn, the amount of the signal lathe vehicle longitudinal direction, that is, the transformed acceleration signal 120 is compared to a predetermined threshold value 110 in threshold value decider 601 . Only if signal 120 is above threshold value 110 is a logical 1 output. In block 130 , it is set that the flag for the angle crash side left back is set if the angle trash was detected in the case at hand. Signal 120 scaled by a factor 130 is then compared in threshold value decider 602 with signal CH 1 140 as well. Only if signal 120 scaled by factor 130 is under signal 140 is a logical 1 output by threshold value decider 602 . Logical AND gate 603 as the logic element outputs a logical 1 604 only if both threshold value decider 601 and 602 have both output such a logical 1 as well. Only then is the flag set for the angle crash side left back.
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A control device and a method for triggering a passenger protection arrangement for a vehicle are provided, at least two acceleration signals being provided by at least two acceleration sensors oriented in different spatial directions. The orientations are angled in relation to a coordinate system oriented toward the vehicle longitudinal direction. The at least two acceleration signals are transformed on at least two axes of the coordinate system. The triggering signal is generated as a function of the comparison of the at least two acceleration signals and the transformed acceleration signals. The passenger protection arrangement is triggered as a function of the triggering signal.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of copending International Application No. PCT/DE01/04523, filed Dec. 3, 2001, which designated the United States and was not published in English.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a phase locked loop for recovering a clock signal from a data signal, having a delay locked loop with a phase detector with a first input that is coupled to a connection for supplying a signal that can be derived from the clock signal, and with a second input that is coupled to a connection for supplying the data signal, with an integrator that is connected to one output of the phase detector, and with a delay element that is connected by a control input to one output of the integrator and that is connected on the output side to one of the two inputs of the phase detector, a loop filter that is connected to the output of the integrator, and a voltage controlled oscillator that is connected on the input side to one output of the loop filter and at whose output the clock signal can be tapped off.
[0003] Recovery of a clock signal from a received data signal, for example, a binary signal with a random sequence of zeros and ones, is a central problem in data technology and telecommunications technology.
[0004] One possible solution approach is to use a phase locked loop with a digital phase detector, which produces an actuating signal for a local oscillator. In such a case, the phase angle of the data signal is compared with the clock phase of the clock signal in a digital phase detector of this type in each case with respect to the flank changes in the data signal, that is to say, the changes from logic 0 to logic 1 and vice-versa The phase detector in such a case produces at its output the information “clock too early”, “clock too late”, or “clock correct or phase unknown”. This signal information is used for keying a frequency of an output signal of a local voltage controlled oscillator (VCO), and, thus, for following the phase angle of the data signal. This principle is specified, by way of example, in the article “Clock Recovery from Random Binary Signals”, J. D. H. Alexander, Electronics Letters Vol. 11, No. 22 (1975), pages 541 to 542 as well as in the article “Si Bipolar Phase and Frequency Detector IC for Clock Extraction up to 8 Gb/s”, A. Pottbäkker, U. Langmann, IEEE Journal of Solid-State Circuits, Vol. 27, No. 12 (1992), pages 1747 to 1751.
[0005] The use of a digital phase detector in a phase locked loop PLL for obtaining a clock signal from a data signal can be implemented quite easily in terms of the circuitry. The digital or nonlinear method of operation of the phase detector is, however, a disadvantage for the transmission system in comparison to a linear method of operation because, in the event of any phase error, only its mathematical sign is known, but not the magnitude of the discrepancy. In consequence, it is not possible to specify a linear transfer function for the system or a modulation bandwidth for the phase modulation. However, because the transmission of data over long distances is a frequent objective in telecommunications technology, in the process of which a large number of signal regenerators have to be connected in series, it is desirable for the circuits used for clock recovery to be linear and to have a well-defined modulation bandwidth.
[0006] German Published, Non-Prosecuted Patent Application DE 198 42 711 A1, corresponding to U.S. Pat. No. 6,433,599 to Friedrich et al., discloses a circuit for data signal recovery and for clock signal regeneration in which, in addition to the PLL for clock recovery with a digital phase detector, a second PLL is provided and has a linear, analog phase detector, is connected downstream from the first PLL, and produces an output clock signal from the clock that is produced in the first stage. However, such a circuit requires a second voltage-controlled oscillator with the additional complexity that is associated therewith.
[0007] The article “A 155-MHz Clock Recovery Delay- and Phase-Locked Loop”, T. H. Lee, J. F. Bulzacchelli, IEEE Journal of Solid-State Circuits, Vol. SC-27, December 1992, pages 1736 to 1746, discloses a circuit of this generic type in which a delay locked loop DLL is combined with a phase locked loop PLL, connected in parallel. It is, thus, possible to achieve very fast clock signal recovery with high performance and good jitter characteristics. The phase detector that is used may, in such a case, assume two or more output values, for example, five output values, which are integrated in a loop integrator to form a triangular waveform signal.
[0008] The loop filter in the control loop that is described in the article has a pure integrator without any proportional component, see FIG. 9, with the function H f =K D /s. The output of this loop filter is connected to a voltage-controlled oscillator VCO. This VCO must be a high-precision crystal oscillator (VCXO), whose frequency differs only insignificantly from the data rate. Any difference between the oscillator frequency and the data rate of the data signal must be compensated for by a steady-state actuating value for the loop filter, which also controls the controllable delay element. This restricts the phase control range of the delay loop, as is explained in the Chapter “C. Acquisition Behavior of the D/PLL”.
[0009] The described D/PLL is configured by the two poles of the phase transfer function (jitter transfer function) H(s), see Chapter B, which can be adjusted by the DLL parameters K D and K Φ as well as the PLL parameter K 0 . However, linear components, in particular, a linear phase detector with a defined detector constant K D , are required for correct configuration of this linear function. This phase detector must be able to make a quantitative statement relating to the phase error, in addition to a qualitative statement.
SUMMARY OF THE INVENTION
[0010] It is accordingly an object of the invention to provide a phase locked loop for recovering a clock signal from a data signal that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that makes possible a linear phase locked loop whose design has been simplified further.
[0011] A clock signal normally has a predefined known sequence of binary coded series of zeros and ones, which, normally, also alternate.
[0012] In contrast, a data signal carries coded information that, for example, is not known a priori to a receiver, such as speech data, text data, graphics data or other data. Thus, even if the use of a scrambler makes it possible to achieve an equal probability of the occurrence of zeros and ones when averaged over a lengthy time period, it is not necessary to know, for example, at the receiver the clock information on which the data signal is based. In consequence, the recovery of a clock signal from a data signal is of major importance in information and communications technology.
[0013] With the foregoing and other objects in view, there is provided, in accordance with the invention, a phase locked loop for recovering a clock signal from a data signal, including a delay locked loop having a connection for supplying a signal to be derived from the clock signal, a connection for supplying the data signal, a nonlinear phase detector having a first input coupled to the connection for supplying the signal, a second input coupled to the connection for supplying the data signal, and at least one output, the nonlinear phase detector producing, at the at least one output, one of a signal able to assume one of only three states including a first state in which a phase of the clock signal leads a phase of the data signal, a second state in which the phase of the clock signal lags the phase of the data signal, and a third state in which a phase angle of the clock signal and a phase angle of the data signal one of match and are instantaneously unknown, and a binary signal, an integrator having an output and an input connected to the at least one output of the phase detector, and a delay element having a control input connected to the output of the integrator and an output connected to one of the first and second inputs of the phase detector, a loop filter having an output, an input connected to the output of the integrator, a proportional regulator component, and an integral regulator component, and a voltage controlled oscillator having an input connected to the output of the loop filter and an output at which the clock signal is to be tapped off.
[0014] According to the invention, a phase locked loop for recovering a clock signal from a data signal is provided and is developed such that the phase detector is a nonlinear phase detector.
[0015] The nonlinearity or digitality of the phase detector is distinguished, in particular, in that, although the phase detector makes a qualitative statement as to whether the phase error between two input signals is positive or negative, it does not make any quantitative statements on the magnitude of this phase error. Such phase detectors are also referred to as “bang-bang detectors.” They are distinguished, in particular, in that their circuitry can be configured with a relatively low level of complexity.
[0016] The output of the phase detector may, in this case, produce a signal that, for example, can assume three values, namely, clock too early, clock correct, or clock too late, depending on whether the phase angle of the clock signal leads or lags that of the data signal, matches it, or is instantaneously not known. A signal such as this at the output may be a ternary signal, which has a positive value when the phase difference has a positive mathematical sign, a negative value when the phase difference has a negative mathematical sign, or the value zero when the phase difference is zero or cannot be determined at that time. The signal at the output, however, does not provide any quantitative statement about the magnitude of the phase difference.
[0017] Alternatively, a binary signal can be produced at the output of the phase detector, providing either a logic zero or a logic one depending on whether the phase difference has a positive or negative mathematical sign.
[0018] This combines the advantages of the PLL combined with a DLL, which allows high performance, with the advantages of simple configuration and simple implementation of a digital phase detector. The delay locked loop DLL with the digital phase detector as well as the integrator and the delay element that may be configured to be controllable in this case, overall, represents a circuit element whose electrical characteristics correspond to those of a linear, analog phase detector.
[0019] According to the present principle, a nonlinear phase detector is used to compare a data signal that arrives in the circuit with a clock signal. In such a case, either the data signal or the clock signal is supplied to the phase detector with a delay. The phase detector may produce an actuating signal, for example, a ternary actuating voltage at its output, which is used to drive an integrator that is connected downstream from the digital phase detector. To form a DLL, the output of the integrator is connected to a delay element that is located either in the data path or in the clock signal path, on the input side of the digital phase detector. The delay element may, in this case, be in the form of a controlled delay element. In such a case, the delay is controlled by the signal that is produced at the output of the integrator.
[0020] This control loop forms a delay locked loop DLL. In this case, either the clock phase is slaved to the data phase or the data phase is slaved to the instantaneous clock phase in a nonlinear, very fast, control process. The output signal from the DLL that is produced at the output of the integrator in this case depends in a linear form on discrepancies between the clock phase and the data signal phase, provided that the delay element that is connected to one input of the digital phase detector has a linear characteristic.
[0021] In the phase locked loop, the signal that is produced at the output of the integrator is, now, filtered in a loop filter that is connected downstream from the integrator, and controls a voltage controlled oscillator that is connected downstream from the loop filter. The loop filter may, in such a case, have a proportional component, which can be used to configure the bandwidth of the PLL, and an integral component, with which the remaining control error between the data signal phase and the clock signal phase can be made to be equal to zero, or can be made as small as possible.
[0022] In accordance with another feature of the invention, the loop filter that is connected downstream from the integrator has a proportional regulator component. This proportional component is used for the actual phase control process. However, to produce a second order phase transfer function in the proposed configuration, the loop filter has an integral component, which introduces the second pole of the transfer function, rather than using the delay loop. In such a case, the integration constant of the integrator is negligibly small. Because time processes in the delay locked loop are always negligibly short in such a case, the phase detector does not need to have a linear response. It is, thus, possible to use a simpler, nonlinear phase detector.
[0023] The two poles of the phase transfer function in the present configuration can be configured using the parameters of the phase locked loop without any defined or linear output value of the phase detector being required for such a purpose.
[0024] The phase transfer function of one preferred embodiment of the invention is, in this case:
H ( s ) = 1 1 + s · K r K 0 · F + s 2 · T K 0 · K d · F
[0025] where F is the transfer function of the loop filter, K τ is the conversion gradient of the delay element (phase/voltage), K 0 is the conversion gradient of the voltage controlled oscillator (circular frequency/voltage), K d is the phase detector constant (voltage/phase), s is the complex circular frequency, and T is the integration time constant of the integrator.
[0026] If the integration time constant T is assumed to be negligibly short, this results in the phase transfer function H(s) becoming
H ( s ) = 1 1 + s K r K 0 F
[0027] This does not include the detector constant K d , in contrast to the phase transfer function K classical (s) of a conventional PLL:
H classical ( s ) = 1 1 + s · K r K 0 · K d · F
[0028] As in classical PLL theory, H(s) in the present configuration is second order if the transfer function F is a first-order piecewise rational function, that is to say, it has an integral component. With the proposed configuration K D , which is undefined for a nonlinear or bang-bang phase detector, can be replaced by the expression 1/K τ for configuration purposes, with the second-order control loop being configured as a linear system even though the phase detector is nonlinear.
[0029] A further advantage of a loop filter with an integral component is that any discrepancy between the VCO frequency and the data rate of the data signal can be compensated for by this integral component. After completion of such a control process, the delay locked loop can be operated with the same drive range as that which is possible without any frequency error. There is, therefore, no need for a high-precision crystal oscillator. In fact, it is even possible to use a voltage-controlled oscillator VCO that can be tuned over a wide range. This is important, especially for high data rates in the Gigahertz range, because it is impossible to produce crystal oscillators for such high frequencies.
[0030] In accordance with a further feature of the invention, the delay element is connected between the connection for supplying the data signal and the second input of the phase detector. The configuration of the delay element in the data path is one possible implementation of the proposed principle, which allows a particularly simple circuit configuration.
[0031] In accordance with an added feature of the invention, in which the delay element is disposed in the data path, one data input of the delay element is connected to the output of the integrator, in order to control it.
[0032] In accordance with an additional feature of the invention, the delay element is connected between the output of the voltage controlled oscillator and the input of the phase detector. The delay element is, in such a case, disposed in the clock path of the circuit.
[0033] In accordance with yet another feature of the invention, if the delay element is disposed in the clock path, it is connected to the output of the integrator, in order to control it.
[0034] In accordance with yet a further feature of the invention, if the delay element is disposed in the clock path, a further delay element is connected to the output in order to provide a clock output signal. In such a case, it is advantageous for the delay element of the further delay element to be shorter than a lower limit of an adjustment limit of the delay time of the delay element in the clock path.
[0035] In accordance with yet an added feature of the invention, if the delay element is disposed in the clock path, a matching cascade circuit having at least one matching delay element is provided for the phase detector and integrator, for matching the data signal phase to the phase angle of the signal that can be tapped off at the oscillator. In consequence, the tolerance range with regard to jitter can be extended as far as the limits that are set by the fast delay locked loop.
[0036] In accordance with a concomitant feature of the invention, the integrator is in the form of a low-pass filter.
[0037] Other features that are considered as characteristic for the invention are set forth in the appended claims.
[0038] Although the invention is illustrated and described herein as embodied in a phase locked loop for recovering a clock signal from a data signal, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
[0039] The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] [0040]FIG. 1 is a block circuit diagram of a first exemplary embodiment of the circuit according to the invention with a controllable delay element in the data path;
[0041] [0041]FIG. 2 is a block circuit diagram of a second exemplary embodiment of the circuit according to the invention with a controllable delay element in the clock path;
[0042] [0042]FIG. 3 is a signal timing diagram illustrating signal waveforms of the clock signals of the circuit of FIG. 2; and
[0043] [0043]FIG. 4 is a block circuit diagram of an alternative configuration of the phase locked loop of FIG. 2 with a matching cascade circuit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] Referring now to the figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown a phase locked loop for recovering a clock signal CL from a data signal DS. A voltage controlled delay element VZS with a signal input S and a control input ST is used to convert the data signal DS to a delayed data signal DS*, which is supplied to the positive input P of a digital phase detector DPD. The clock signal CL is supplied to a further, negative input, denoted M, of the digital phase detector DPD. An actuating voltage UB can be tapped off at one output of the digital phase detector DPD, and provides a voltage value as a function of the phase angles between the input signals. The actuating voltage UB is, in this case, a ternary voltage that, for example, assumes a positive voltage value when the phase angle of the data signal DS* is too early with respect to the phase angle of the clock signal CL, assumes a negative value when it is too late, and assumes the value zero when the phase angles match one another or no information can be obtained from the data signal because there are no flank changes in the data signal DS. An integrator IR, whose time constant is T, is connected to the output of the digital or nonlinear phase detector DPD. This time constant T is, in this case, set such that a mean voltage UD is produced at the output of the integrator IR, which is, in each case, smoothed over a number of data bits of the data signal DS. The mean voltage UD is used to control the voltage controlled delay element VZS by supplying it to the control input ST of the delay element VZS. With the definition of the actuating voltage UB as stated above, by way of example, the mean voltage UD acts on the delay element VZS such that its delay element increases as the magnitude of the mean voltage UD increases. In consequence, a leading phase of the data signal DS is increasingly delayed, so as to compensate for this lead. The circuitry including the digital phase detector DPD, integrator IR, and controllable delay element VZS forms a delay locked loop DLL. In such a case, the phase angle of the delayed data signal DS* is slaved to the phase of the clock signal CL in a nonlinear control process, which is, in this case, very fast. The mean voltage UD that is produced at the output of the integrator IR depends on the discrepancy between the phase of the data signal DS and the phase angle of the clock signal CL. If the voltage controlled delay element VZS has a linear characteristic, then fluctuations in the phase angle of the data signal DS with respect to the phase angle of the clock signal CL are transferred in a linear manner to the mean voltage UD.
[0045] A loop filter LF is, furthermore, connected to the output of the integrator IR, and a voltage controlled oscillator VCO is connected to the output of the loop filter so that the mean voltage UD can be used in a phase locked loop to control the frequency of a signal that can be tapped off at the output of the voltage controlled oscillator VCO. The output signal from the voltage controlled oscillator VCO is actually the clock signal CL that is supplied to the first input of the digital phase detector DPD. The loop filter LF has a transfer function F(s) that has a proportional component and an integral component. The proportional regulator component can be adjusted to adjust the bandwidth of the phase locked loop. The proportional component and integral component can also be configured such that the residual control error between the phase angle of the clock signal CL and the phase angle of the data signal DS* is zero.
[0046] The settling time of the delay locked loop DLL can be set such that it is short in comparison to the settling time of the higher-level phase locked loop. The integration time constant T of the integrator IR can be chosen to be correspondingly short. On the other hand, the integration time constant T should be chosen to be sufficiently long that the mean voltage UD is smoothed over a number of period durations of the data signal without in the process governing the control processes of the higher-level phase locked loop.
[0047] In consequence, in the present exemplary embodiment, a nonlinear digital phase detector DPD is disposed in a delay locked loop DLL, with a linear, analog signal being produced at the output of the integrator IR in the delay locked loop DLL, as a measure of the instantaneous control error between the phase angles of the clock signal CL and of the data signal DS. Such a digital phase detector DPD can be produced to be particularly simple. The loop filter LF is a filter that has a proportional component and an integral component so that the clock phase can be slaved to the phase angle of the data signal without any residual control error.
[0048] [0048]FIG. 2 shows a block diagram of an alternative embodiment of the phase locked loop for recovering a clock signal CL from a data signal DS. In this case, and in contrast to the phase locked loop shown in FIG. 1, the voltage controlled delay element VZS is not disposed in the data path, but in the clock path. The data signal DS is, accordingly, supplied directly to one of the inputs of the digital phase detector DPD, namely the positive input P, and the voltage controlled delay element VZS delays the clock signal CL that can be supplied to the digital phase detector DPD by a time delay TD so that a delayed clock signal CL 1 is supplied to the digital phase detector DPD. As in the first exemplary embodiment, the mean voltage UD is applied to the control input ST of the voltage controlled delay element VZS to control the time delay TD. The mean voltage UD is also passed through a loop filter LF to drive a voltage-controlled oscillator VCO, at whose output the clock signal CL is produced. A further delay element VZ, which is connected to the output of the voltage controlled oscillator VCO and has a time delay τ produces a clock output signal CL*, which corresponds to a data output signal D 0 that can be tapped off from the digital phase detector DPD. The digital phase detector DPD and the integrator IR are combined to form a detector unit DU.
[0049] As shown in FIG. 1, the actuating voltage is a ternary voltage, whose voltage value carries the information clock too early, clock correct, or clock too late. The mean voltage UB in this case depends on the phase angle of the data signal DS relative to the phase angle of the delayed clock signal CL 1 . The mean voltage UD corresponds to a smoothed actuating voltage UB, which is constant, or virtually constant, over a number of data bits of the data signal DS. The mean voltage UD is used to set the time delay TD of the voltage controlled delay element VZS. The delay loop DLL shown in FIG. 2, which includes the digital phase detector DPD, the integrator IR, and the voltage controlled delay element VZS, follows the phase of the delayed clock signal CL 1 in a nonlinear manner, but follows the phase angle of the data signal DS very quickly. In contrast, slow fluctuations in the data phase are transferred linearly to the mean voltage UD, with the voltage controlled delay element VZS having a linear characteristic. This eliminates the nonlinear characteristics of the phase detector DPD because the phase difference that can be identified by the digital phase detector is very quickly reduced to zero in the delay locked loop DLL.
[0050] The mean voltage signal UD that can be produced by the delay locked loop DLL at the output of the integrator IR and that is proportional to phase fluctuations in the data signal DS with respect to the clock signal CL 1 , drives a voltage controlled oscillator VCO through a loop filter LF.
[0051] In comparison to the phase locked loop shown in FIG. 1, the phase locked loop shown in FIG. 2 has the advantage that a voltage controlled delay element VZS that is inserted into the clock path can be produced with simpler circuitry than one disposed in the data path.
[0052] [0052]FIG. 3 shows the clock signal waveforms of the clock signals from FIG. 2. The diagram of FIG. 3 shows the clock signal CL that can be tapped off at the output of the voltage controlled oscillator VCO, the clock output signal CL*, and the clock signal CL 1 , which is delayed by the time delay TD by the voltage controlled delay element VZS. The time delay of the clock output signal CL* with respect to the clock signal CL is annotated τ. The time delay TD can be adjusted in a limited range, in an interval with the interval boundaries T MIN to T MAX . The interval boundaries T MIN , T MAX are subject to the following conditions: the minimum delay time T MIN must be longer than the time delay τ of the further delay element VZ; and T MAX must be shorter than the sum of the time delay τ and the period duration of the oscillator signal TP. If flipflops, which have significant set and hold times, are used for the circuit, then these set and hold times must be taken into account when setting the conditions for the interval boundaries of the delay times TD.
[0053] [0053]FIG. 4 shows a matching cascade circuit, which can be connected to the detector unit DU shown in FIG. 2. The matching cascade in this case has two or more delay elements T1 to Tn and τ 1 to τ n , by which the phase angle of the data signal DS can be successively matched to the phase angle of the clock signal CL at the output of the oscillator VCO. In such a case, delay elements with a fixed delay time τ 1 to τ n are provided on one hand, and delay elements with a variable delay time T1 to Tn are provided on the other hand. The reference symbols τ k (k=1 . . . n) and T k (k=1 . . . n) in this case denote not only the corresponding components but also the delay time of the respective component.
[0054] The condition τ k−1 +T k ≧τ k must be satisfied for a matching cascade circuit that is operating without any error so that the kth flipflop is triggered before or together with the (k−1)th flipflop, as is the case in the normal shift registers. In consequence, the minimum delay time of a delay element is given by: T kmin ≧τ k −τ k−1 . The maximum delay time of a delay element is T MAX =TP+τ k −τ k−1 . If the data interval is fully utilized, then T MAX =TP+T MIN . It follows from this that the delay time of a delay element T k may, at most, cover a period duration TP, for example, from T kmin to T kmin +TP. The tolerance of the phase locked loop to jitter is, accordingly, increased to n times 2π for n cascade changes. In this case, however, the set and hold times of the flipflops FF 1 to FFn, which are connected to the delay elements τ1 to τn have been ignored. The delay elements with an adjustable delay time T 1 to T n , in FIG. 4 replace the controllable delay element VZS in FIG. 2. The mean voltage UD controls the delay times of all the controllable delay elements T 1 to T n , in FIG. 4. The output of the oscillator VCO in FIG. 2 is connected to the input of both the controlled delay element T n and of the uncontrolled delay element τ n . The output of the controlled delay element T 1 , at which the delayed clock signal CL 1 is produced, is connected to the digital phase detector DPD in the detector unit DU. The controlled delay elements T 1 to T n , are connected in series. The clock input C of a flipflop FFK, (k=1 . . . n) is connected to the output of the respective uncontrolled delay element τ k . The flipflops FFk are connected in series with one another, with the data input D of the first flipflop FF 1 being connected to the data output D 0 of the detector unit DU, and a data output signal D n can be produced at the data output Q of the n-th flipflop FFn.
[0055] The matching cascade circuit shown in FIG. 4 allows the data output signals at the output of the digital phase detector DPD to follow even major phase modulations of the input data signal DS, at frequencies above the configured PLL bandwidth, as a function of the speed of the delay locked loop DLL.
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A phase locked loop for recovering a clock signal from a data signal including a delay locked loop with a nonlinear digital phase detector. The delay locked loop that is embedded in the phase locked loop acts like a linear phase detector. The phase locked loop of the present invention can be produced at low cost and is particularly suitable for use in data communication.
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REFERENCE TO PRIORITY APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 12/823,383, filed Jun. 25, 2010 and this application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 61/473,573, filed Apr. 8, 2011. These patent applications are incorporated herein by reference in their entireties.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to firearms comprising components fabricated from dissimilar metallic materials and, more specifically, to firearms comprising components fabricated from metallurgically bonded multi-metallic materials and to firearms components comprising metallurgically bonded multi-metallic materials. Methods for manufacturing such components and firearms are also disclosed.
BACKGROUND OF THE INVENTION
[0003] Firearms such as handguns (e.g., pistols), including semi-automatic handguns, have been in use for centuries. The M1911 pistol, for example, originated in the late 1890s and it, in addition to several other handguns, were adopted for military service in the early 1900s. Various types of handguns, including single and double action semi-automatic pistols are used by military and law enforcement personnel, as well as by individuals, throughout the world.
[0004] Many of the components of firearms experience high impact during firing and must be constructed from materials that have high strength and corrosion-, impact- and wear-resistant properties. These components are largely constructed from metallic materials having high strength, as well as corrosion-, wear- and impact-resistance properties, such as various iron-containing metallic materials, including stainless steel materials. Other components that do not experience high impact or wear, or do not require high strength, are sometimes constructed from aluminum or polymeric materials. Some firearms have been fabricated using all stainless steel components, while others are constructed from a combination of iron-containing materials, non-iron containing materials, and polymeric materials. Firearm components are generally fabricated using various metal stamping, machining, milling, metal forming, casting, forging, and other techniques. Individual components may be welded to one another to form assemblies.
[0005] Because many firearm components are generally constructed, entirely or nearly entirely, of heavy, rigid, durable materials such as various types of stainless steel and other iron-containing materials, the overall weight of firearms is generally substantial. It is desirable, for many applications, to reduce the overall weight of firearms without reducing the strength, or the corrosion-, impact- and wear-resistance and reliability of the firearms and their components. U.S. Pat. No. 6,711,819, for example, relates to firearms having lightweight but strong components made of scandium containing aluminum alloys, which are composed of an aluminum alloy containing alloying elements including, in addition to aluminum, from about 0.05% to about 00.30% scandium with other elements such as magnesium, chromium, copper and zinc.
[0006] In other attempts to reduce weight, yet maintain the other desirable properties, firearms have been constructed using components having different metallic compositions, such as using a stainless steel slide component and an aluminum body. Other attempts to reduce the weight of firearms have involved the use of wear-resistant polymeric materials on the frame, generally in combination with an iron-containing slide component. Some components, such as triggers, have been fabricated from lighter weight alloy materials such as titanium-containing materials. While most firearm barrels are composed of iron-containing materials, at least one attempt to reduce the weight of a barrel is shown in U.S. Pat. No. 6,189,431, which discloses a lightweight composite gun barrel for a small caliber firearm having a substantially metallic liner and an outer layer comprising fiber reinforced resin.
[0007] The explosion bonding phenomenon was observed during World War II when the force of explosions was observed to metallurgically weld bomb fragments to impacted metal objects. DuPont developed a practical explosion bonding process for bonding different metallic materials in the early 1960s, which is described in U.S. Pat. No. 3,140,539.
[0008] The art of explosion bonding materials is well known. In general, explosion bonding is a solid-state welding process that uses controlled explosive energy to force two or more metals together at high pressures. The constituent metallic layers of the resultant multi-layer composite system are joined by a high quality metallurgical bond which generally forms an abrupt transition from the one metallic layer to the other dissimilar metallic layer with virtually no degradation of the physical and mechanical properties of the constituent metallic layers. The two most common resultant bulk shapes of explosively bonded materials are rectangular sheet materials having planar bond lines and cylindrical materials having cylindrical bond lines.
[0009] A wide range of metals can be explosively bonded to one another and multiple layers of dissimilar metals bonded to one another in sequence to form multi-layer bonded metallic substrates are not uncommon. Bonded bi- or multi-metallic substrates can be machined and incorporated into a variety of products. Applications for such materials include weld transitions between dissimilar metal components, precious metal conservation, galvanic corrosion prevention, corrosion-resistant linings, bearing surfaces, and radiation shielding. These materials are used in industries as diverse as hermetic electronic packaging, marine shipbuilding, chemical processing, golf clubs, sputter targets and cooking griddles.
SUMMARY OF THE INVENTION
[0010] In general, lighter weight firearms and firearms components are desirable. Many firearms components have strength, hardness, wear-resistance, impact-resistance and/or durability requirements, however, that lighter weight materials in general don't satisfy. For many firearms components, high wear- and impact-resistance properties are required at certain load or bearing points, or at interfaces with other components, while other component areas have less rigorous material requirements. The applicant proposes using lightweight metallic material(s), such as aluminum or an aluminum-containing material or alloy, that is intimately and reliably bonded to a high strength, high impact- and wear-resistant material, such as an iron-containing or titanium-containing material, to provide a bonded multi-metallic material for use in the construction of firearms and firearms components. The applicant discovered, unexpectedly, that metallurgically bonded multi-metallic materials composed of metals having different properties and comprising, for example, a generally lightweight material, such as aluminum or an aluminum-containing metallic material, metallurgically bonded to a higher strength, more wear- and impact-resistant metallic material, such as an iron- or titanium-containing metallic material, are highly desirable for use in the construction of firearms and firearms components.
[0011] The metallurgically bonded multi-metallic materials used for fabricating firearms components of the present invention comprise at least two dissimilar metallic materials and are generally provided as a multi-layered substrate. Metallurgically bonded multi-metallic materials and firearms components of the present invention may comprise at least two dissimilar metallic materials provided as at least two or more distinct metallic layers having at least one metallurgical bond region. In general, the term “metallurgical bond,” as it is used in this specification, refers to a bond between two metals whose interface is predominantly free of voids, oxide films and discontinuities. In many cases, a metallurgical bond is characterized by a reaction zone between the two metals that is on the order of several atomic layers on the surface of each metal.
[0012] At least two dissimilar metals may be bonded directly to one another, as is known in the art, using a technique such as explosion bonding. Explosively bonded multi-metallic materials are known in the art and are available commercially. Explosively bonded multi-metallic substrates are generally fabricated by stacking dissimilar metallic layers (e.g., having a flat sheet, cylindrical or another tubular form) next to one another and using explosive charges to bond them to one another. The explosions generate significant instantaneous pressures across the interface surfaces of the dissimilar metals to bond them to one another. Alternatively, certain metallurgically bonded multi-metallic materials may be provided using other techniques, such as metal cladding, high pressure and thermal bonding techniques, roll bonding techniques, casting techniques, or the like.
[0013] In some embodiments, at least two dissimilar metals may be bonded directly to one another using roll-bonding or similar techniques. Additional dissimilar metal layers, or additional metal layers having compositions similar to or the same as those they bond to, may be provided using roll bonding, explosion bonding, and other metal joining techniques. Some multi-metallic bonded substrates of the present invention may thus contain multiple metal bond regions formed using different bonding techniques. In one embodiment, multi-metallic substrate materials comprise dissimilar metal layers metallurgically bonded to one another along a bond zone formed by roll bonding with at least on additional layer metallurgically bonded to one of the metal layers along a bond zone formed by a technique other than roll bonding, such as an explosive bonding technique. In preferred embodiments, each of the bonding regions is characterized by a reaction zone between adjacent metals (similar or dissimilar) that is on the order of several atomic layers thick.
[0014] Bonded multi-metallic substrates used for fabricating firearms and firearms components of the present invention are generally provided as sheet materials, cylindrical shapes or other tubular shapes, from which rough blanks may be machined or otherwise fabricated. Layers of constituent metallic materials may be as thin as about 0.1 cm or less, and up to 10 cm or more thick. Metallurgical bond regions are typically planar when the bonded multi-metallic materials are provided in a sheet or sheet-like form. The constituent layers may have a generally uniform thickness, or they may have a non-uniform thickness. Alternatively, the bond region may be generally tubular or cylindrical in bonded multi-metallic materials having a tubular or cylindrical configuration.
[0015] Firearms and firearms components of the present invention are thus constructed from bonded multi-metallic base materials comprising at least two dissimilar metallic materials having different properties, such as weight, density, wear-resistance, impact-resistance, durability, hardness, toughness, metallic luster, color and the like, bonded to one another. The firearms components are generally designed and fabricated from multi-metallic material substrates such that the metallic material having higher strength, toughness, impact- and/or wear-resistance is positioned at load and/or bearing points, wear points, impact points and/or interfaces with other components, while the metallic material having a lower weight and, generally, lower impact- and wear-resistance properties, is positioned at other component locations that have less rigorous material property requirements.
[0016] Firearms components of the present invention may be fabricated from metallurgically bonded multi-metallic materials including combinations of various iron-containing metals and alloys such as steels and steel alloys identified by the American Iron and Steel Institute designations ranging from 1000 to 7000 and including specifically and without limitation, steel alloys 4140, 4340 and 8620, as well as stainless steels, e.g. stainless steels identified by the American Iron and Steel Institute designations ranging from 200 to 400 and including specifically and without limitation, stainless steels 301, 302, 303, 303Se, 304, 304L, 309, 316, 316L, 321, 410, 416, 440A, 440B and 440C bonded to non-iron containing metallic materials. Exemplary non-iron containing metallic materials include, without limitation, aluminum and aluminum-containing metals and alloys such as Aluminum Association alloys from the 1000 through 7000 series, inclusive, and including specifically and without limitation, aluminum alloys 2024, 5086, 6061, 6062, 6063, and 7075, as well as aluminum alloys containing scandium and/or other alloying elements, titanium and titanium-containing metals and alloys such as SAE/ASTM Unified Numbering System alloys of the R50000 series and including, without limitation, titanium alloys having an ASTM B 265 designation ranging from Grades 1-35, magnesium and magnesium-containing metals and alloys such as SAE/ASTM Unified Numbering System magnesium alloys of the M10000 series, copper-containing metals and alloys such as SAE/ASTM Unified Numbering System copper alloys of the C20000 through the C70000 series inclusive, and the like.
[0017] In some embodiments, firearms components of the present invention may be fabricated from bonded multi-metallic materials including combinations of at least two different iron-containing metals and alloys bonded to one another. Generally, the constituent metals and/or alloys bonded to one another to form the bonded multi-metallic substrates used in the present invention have different elemental compositions and different physical properties but, in some embodiments, the constituent metals and/or alloys of the multi-metallic substrates may have similar elemental compositions and/or physical properties but different magnetic properties, appearances, colors, metallic lusters, and the like. Constituent metals and alloys, and multi-metallic combinations forming the bonded multi-metallic material may be chosen based on rigidity, density, cost, corrosion-resistance, hardness, wear-resistance, impact-resistance, mechanical properties, weight, fracture toughness, fatigue-resistance, metallic luster, color, creep-resistance, elastic modulus, yield strength, resistance to stress, corrosion and/or cracking, machinability, magnetic properties, anti-galling properties, and the like.
[0018] In one embodiment, for example, bonded multi-metallic materials and firearms components of the present invention may comprise an iron-containing layer in combination with a metallic layer having different properties, such as a titanium-containing layer, an aluminum-containing layer, a copper-containing layer, a magnesium-containing layer, or another metallic material having properties different from those of the iron-containing layer. In another embodiment, firearms components of the present invention may incorporate iron-containing surface layers providing high impact- and wear-resistance, with a different material, such as an aluminum-containing and/or titanium-containing material positioned as an intermediate layer, providing lighter weight or other properties different from those of the iron-containing layer(s). Bonded multi-metallic substrates having several distinct metallic layers composed of several distinct metallic materials may be used. Multiple layers may have different thicknesses and the thickness of individual layers may be constant, or may vary, over the surface area of the substrate material.
[0019] Exemplary bonded multi-metallic substrate materials include, for example: an iron-containing metal or alloy, such as a steel alloy or stainless steel bonded to aluminum or an aluminum-containing metal or alloy; an iron-containing metal or alloy, such as a steel alloy or stainless steel bonded to titanium and/or a titanium-containing metal or alloy; an iron-containing metal or alloy, such as a steel alloy or a stainless steel bonded to magnesium or a magnesium-containing metal or alloy; titanium or a titanium-containing metal or alloy bonded to aluminum or an aluminum-containing metal or alloy, or to magnesium or a magnesium-containing metal or alloy; a copper-containing metal or alloy bonded to an aluminum-containing metal or alloy; a copper-containing metal or alloy bonded to magnesium and/or a magnesium-containing metal or alloy; a copper-containing metal or alloy bonded to titanium and/or a titanium-containing metal or alloy; steel or a steel-containing metal or alloy bonded to copper and/or a copper-containing metal or alloy; and a stainless steel-containing alloy bonded to copper and/or a copper-containing metal or alloy. Additional metallic layers comprising any of the materials listed above may also be incorporated in the bonded multi-metallic substrate materials.
[0020] Firearms components of the present invention are generally fabricated using a multi-layer substrate of the bonded multi-metallic material at least as thick as the final thickness of the desired component. Component patterns are generally positioned or drawn or imaged and oriented on bonded metallic substrate materials so that the material bond line(s) are oriented and positioned as desired in the final component and the substrate material is cut, machined, punched, water jetted, sawn or otherwise mechanically divided to produce a rough component blank. Rough component blanks may then be further formed or refined to desired specifications by machining, or using other suitable methods, to the desired final component configuration and three dimensional conformation while maintaining the desired orientation and position of bond line(s).
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1A shows a schematic perspective drawing of a bonded multi-metallic substrate material with a pattern for forming a rough blank of a firearm frame component, and FIG. 1B shows a schematic perspective drawing of a firearm frame component fabricated from a bonded multi-metallic substrate of FIG. 1A machined to form a final, finished multi-metallic frame component.
[0022] FIG. 2A shows a schematic perspective drawing of another embodiment of a bonded multi-metallic substrate material with a pattern for forming a rough blank of a firearm frame component, and FIG. 2B shows a schematic perspective drawing of a firearm frame component fabricated from a bonded multi-metallic substrate of FIG. 2A machined to form a final, finished multi-metallic frame component.
[0023] FIG. 3 shows a schematic perspective drawing of a firearm slide component of the present invention fabricated from a bonded multi-metallic base material composed of multiple metals bonded to one another.
[0024] FIGS. 4A-4C schematically illustrate multiple embodiments of a firearm sear component of the present invention fabricated from multi-metallic base sheet materials having different structures and configurations.
[0025] FIGS. 5A and 5B show schematic drawings of two embodiments of a firearm hammer component of the present invention fabricated from a multi-metallic base she material composed of multiple metals bonded to one another with the bond line arranged in different locations.
DESCRIPTION OF THE INVENTION
[0026] In one embodiment, firearms components of the present invention are fabricated from bonded multi-metallic materials provided as explosively bonded metallic materials. The bonded multi-metallic materials may comprise multiple metallic materials having different compositions and different properties, with an interface region and a bond zone provided between each set of metallic layers. The constituent metallic layers may contact one another directly in the interface region and bond zone. Alternatively, metallic interlayers may be provided between adjoining metallic layers.
[0027] Bonded multi-metallic materials may comprise at least two metallic layers composed of at least two different metallic materials having different properties. Bonded multi-metallic materials are generally constructed as sheet materials, and firearms components of the present invention may be machined or otherwise fabricated from sheet material substrates. In some cases, bonded multi-metallic base materials may be constructed as cylindrical base structures and firearms components are machined from the cylindrical base structures. Non-metallic materials, including various types of rubbery materials, plastics, thermoplastics, wood and the like may be mounted, or fastened, on an outer surface of the bonded multi-metallic components, or within recesses or cavities of the bonded multi-metallic components, for functional and decorative purposes.
[0028] Exemplary bonded multi-metallic materials include metallic base materials comprising various ferrous and non-ferrous metals and alloys (e.g., stainless steels such as AISI 300 series and/or 400 series stainless steels, titanium and titanium-containing materials and alloys such as ASTM B265 Grades 1 through 5, copper-nickel alloys such as Monel™ K500, and copper-aluminum alloys such as aluminum-bronze) bonded to other metallic materials including aluminum and aluminum-containing metals and alloys, such as AA6061 and/or AA 7075 as well as aluminum alloys containing scandium, and magnesium or magnesium-containing materials and alloys such as AZ80A. The bonded multi-metallic material may also incorporate metallic interlayers between the constituent metals to facilitate bonding or to provide other desirable properties. In some embodiments, metal matrix composites and cermet materials may be used as constituent materials forming bonded multi-metallic materials and are considered “metallic” materials for purposes of this disclosure.
[0029] The bond zone preferably has a generally uniform physical and mechanical structure along the interface region and preferably provides an abrupt transition from one metallic layer to the other with no substantial degradation of the physical and mechanical properties of either of the constituent metals. The bond zone is preferably characterized by a metallurgical bond region that extends on the order of several atomic layers on the surface of each metal and doesn't materially change the physical and mechanical properties of either of the metals. Alternatively, the bond zone may include one or more interlayer(s) comprising another constituent material that promotes bonding of the two dissimilar metals with no substantial degradation of the physical and mechanical properties of either of the constituent metals. Niobium- and tantalum-containing materials are used as interlayer materials for some applications.
[0030] The thickness dimension of the constituent metallic layers forming the bonded multi-metallic material may be generally equivalent or, in some embodiments, may be unequal. In one embodiment, a bonded multi-metallic material may comprise a stainless steel or another generally heavy, hard, impact- and wear-resistant material having a thickness less than that of another, lighter weight metallic material, such as an aluminum- or titanium- or magnesium-containing metal. In one embodiment, a heavier metallic layer has a thickness of no more than about 50% the thickness of the lighter weight metallic layer; in some embodiments the heavier metallic layer has a thickness of no more than about 40% the thickness of the lighter metallic layer; in other embodiments, the heavier metallic layer has a thickness of no more than about 25% the thickness of the lighter metallic layer; in yet other embodiments, the heavier metallic layer has a thickness of no more than about 10%, or no more than about 5%, the thickness of the lighter metallic layer.
[0031] In some embodiments, the bonded multi-metallic material comprises layer of a generally hard, impact- and wear-resistant material on either side of one or more intermediate layer(s) having generally lighter weight properties. In this embodiment, the two opposite surface layers may comprise the same or different materials, and may have equivalent or different thicknesses. The lighter weight intermediate layer, likewise, may have a thickness equivalent to that of one or both surface layers, or may have a different, and generally larger, thickness. In some embodiments, the sum of the thicknesses of the surface layers may be less than that of intermediate layer(s). In one embodiment, the sum of the thicknesses of the surface metal layers is no more than about 50% the thickness of the intermediate layer(s); in some embodiments the sum of the thicknesses of the outer surface metal layer(s) is no more than about 40% the thickness of the intermediate layer(s); in other embodiments, the sum of the thicknesses of the outer surface metal layer(s) is no more than about 25% the thickness of the intermediate layer(s); in yet other embodiments, the sum of the thicknesses of the outer surface metal layer(s) is no more than about 10%, or no more than about 5%, the thickness of the intermediate layer(s).
[0032] FIG. 1A shows a schematic diagram illustrating a bonded multi-metallic material substrate with a firearm frame member pattern superimposed on the substrate. In this illustrative embodiment, the bonded multi-metallic base material substrate 10 is composed of a sheet comprising a first wear and impact-resistant metallic layer 12 bonded to a second, dissimilar and lighter weight metallic layer 14 along an interface region at bond zone 15 . The bonded multi-metallic substrate material may be fabricated using explosion bonding (or explosion welding) techniques that are known in the art, or using other techniques that provide a solid state bond between the constituent metallic layers. As shown in FIG. 1A , the more wear- and impact-resistant metallic layer 12 is arranged at the upper portion of the firearm frame member where the frame member experiences impact and movement in relation to other surfaces or components, such as the barrel and slide. The lighter weight metallic layer 14 is arranged to form the lower portion of the frame member and the handle or grip, which experiences less impact and movement in relation to other components.
[0033] The heavier and more impact resistant constituent metallic material is preferably at least thick enough to form the exposed surface of the upper portion of the frame member that receives and interfaces with the barrel and the slide. In some embodiments, the thickness M 1 of the heavier and more impact resistant constituent metal is less than about 3 cm; in other embodiments, thickness M 1 is less than about 2 cm thick; in still other embodiments, thickness M 1 is less than about 1 cm thick. In particular embodiments, the thickness M 2 of the lighter constituent metallic material is generally at least about 6 cm; may be at least about 8 cm thick; and, in yet other embodiments, may be more than 10 cm, or more than 12 cm thick. The depth D of the multi-metallic base material substrate is generally approximately equivalent to or slightly larger than the dimensions of the final frame component.
[0034] A frame member blank may be cut, machined or otherwise separated from the substrate according to the pattern shown schematically in FIG. 1A . The frame member blank may then be further machined to provide the desired three dimensional configuration and surface conformation of the finished frame member component 16 , shown in an exemplary configuration in FIG. 1B . The frame component may undergo further treatment and processing, such as the application of other materials and surface treatments.
[0035] FIGS. 2A and 2B shows schematic diagrams illustrating another embodiment of a bonded multi-metallic material substrate and a finished firearm frame member blank constructed from the substrate. In this illustrative embodiment, the bonded multi-metallic base material substrate 10 ′ is composed of a sheet comprising a first wear and impact-resistant metallic layer 12 ′ bonded to a second, dissimilar and lighter weight metallic layer 14 A along an interface region at bond zone 15 ′. Bond zone 15 ′ is preferably a metallurgical bond zone and may be provided by roll bonding, explosive bonding, metal cladding, high pressure and thermal bonding techniques, casting techniques, or the like.
[0036] In this embodiment, the thicker metallic layer 14 ′ is composed of multiple metallic layers 14 A, 14 B, 14 C and 14 D, with multiple bond regions 15 A, 15 B and 15 C formed at the interfaces of the neighboring metallic layers. Each of the metallic layers 14 A, 14 B, 14 C and 14 D may comprise the same or a similar metallic material; alternatively, different layers may be composed of different metallic materials. Each bond region 15 A, 15 B and 15 C may be provided using a metallurgical bonding technique, such as roll bonding, explosive bonding, metal cladding, high pressure and thermal bonding techniques, casting techniques, and the like, and each bond region 15 A, 15 B and 15 C is preferably a metallurgical bond zone.
[0037] In one embodiment, a wear- and impact-resistant metallic layer 12 ′ comprising an iron- or steel- or titanium-containing metallic material, such as a stainless steel material, is arranged at the upper portion of the firearm frame member where the frame member experiences impact and movement in relation to other surfaces or components, such as the barrel and slide. A lighter weight metallic layer 14 A comprising, for example, an Aluminum- or titanium-containing metallic material, is bonded to layer 12 ′ at bond zone 15 ′, with the metallurgical bond region formed using a roll bonding technique. An additional metallic layer 14 B may comprise a metallic material that is the same as or different from the material of layer 14 A, and bond zone 15 A at the interface of layers 14 A and 14 B, is a metallurgical bond formed using a technique other than roll bonding, such as explosive bonding. Optional additional metallic layers 14 C and 14 D, comprising metallic materials that are the same as or different from the material of layers 14 A, 14 B, etc., incorporate bond zones 15 B, 15 C, etc., at layer interfaces, which are characterized by metallurgical bonds formed using any one of a variety of techniques, including explosive bonding techniques. This is an example of metallic substrate materials composed of metallic layers, at least one metallic layer comprising a material that is dissimilar from at least one other metallic layer, wherein the bond zones are characterized by metallurgical bonds formed using at least two different metal bonding techniques.
[0038] In one embodiment, a wear- and impact-resistant metallic layer comprising stainless steel, for example, is bonded to a lighter weight metallic layer along a metallurgical bond region formed by roll bonding, while an opposing surface of the lighter weight metallic layer is bonded to another metallic layer of the same or a different composition along a metallurgical bond region formed by explosive bonding techniques. One exemplary bonded multi-metallic material comprises a relatively thin layer of a wear- and impact-resistant metallic layer bonded to a relatively thin layer of a lighter weight metallic layer along a metallurgical bond region formed by roll bonding, while an opposing surface of the lighter weight, relatively thin metallic layer is bonded to a thicker layer of another metallic layer along a metallurgical bond region formed by explosive bonding. The thickness of the wear- and impact-resistant metallic layer may be less than 1 inch and, in some embodiments, less than ½ inch. The thickness of the relatively thin layer of lighter weight metallic material bonded to the wear- and impact-resistant metallic layer may also be less than 1 inch and, in some embodiments, may be no more than 50% more, or less, than the thickness of the wear- and impact-resistant metallic layer. The thickness of the thicker metallic layer bonded to the relatively thin layer is generally at least twice the thickness of the neighboring thinner layer, and may be at least 4 times, or 6 times, or 10 times or more the thickness of the neighboring thinner layer.
[0039] The heavier and more impact resistant constituent metallic material is preferably at least thick enough to form the exposed surface of the upper portion of the frame member that receives and interfaces with the barrel and the slide. In some embodiments, the thickness M 1 ′ of the heavier and more impact resistant constituent metal is less than about 3 cm; in other embodiments, thickness M 1 ′ is less than about 2 cm thick; in still other embodiments, thickness M 1 ′ is less than about 1 cm thick. In some embodiments, a composite metallic material composition formed by multiple metal layers, such as 14 A, 14 B, 14 C and 14 D comprises a lighter constituent metallic material and, in the aggregate, is at least about 6 cm thick; may be at least about 8 cm thick; and, in yet other embodiments, may be more than 10 cm, or more than 12 cm thick.
[0040] A frame member blank may be cut, machined or otherwise separated from the multi-metallic substrate according to the pattern shown schematically in FIG. 2A . The frame member blank may then be further machined to provide a desired three dimensional configuration and surface conformation of the finished frame member component 16 ′, shown in an exemplary configuration in FIG. 2B . The frame component may undergo further treatment and processing, such as the application of other materials and surface treatments.
[0041] The surfaces of framework member 16 , 16 ′ that experience high impact and relative movement, shown as the upper surfaces of frame member component 16 , 16 ′ where the framework member engages the slide, are formed by the more impact-resistant metallic material layer 12 , 12 ′ and bond line 15 , 15 ′ is arranged below these surfaces in the finished component. In some embodiments, the upper area of the framework member that engages the slide comprises a steel alloy such as 4140 and/or a stainless steel alloy such as 303 or 304L. In another embodiment, the upper area of the framework member that engages the slide comprises a titanium-containing material or alloy, such as a titanium alloy having an ASTM B 265 designation ranging from Grades 1 through 35. A lighter weight and/or less impact resistant metallic material forms the lower portion of the frame member, which experiences less impact and movement in relation to other components. In some embodiments, the lower portion of the frame member comprises an aluminum-containing material, such as aluminum alloy 6061 or 6062. In alternative embodiments, the lower portion of the frame member comprises a titanium-containing alloy having an ASTM B 265 designation ranging from Grades 1 through 35, and in some embodiments, the lower portion of the frame member comprises titanium alloy Grade 2.
[0042] FIG. 3 illustrates an exemplary firearm slide component composed of a bonded multi-metallic material having a different composition and configuration. In this illustration, slide component 20 is fabricated from a bonded multi-metallic material comprising outer (e.g., upper and lower) layers 22 , 24 arranged on opposite surfaces of the bonded multi-metallic material substrate with an intermediate layer 26 comprising a lighter weight metallic material or a metallic material having another property different from that of the outer layers. The outer surface layers 22 , 24 may be composed of the same or different materials. In one embodiment, for example, outer surface layers 22 and 24 comprise an iron-containing metal such as a stainless steel, and the intermediate layer comprises a lighter weight metallic material such as aluminum, an aluminum-containing material or alloy, titanium, a titanium-containing material or alloy, or the like. The interface zones are shown as bond lines 23 , 25 , which may be provided as direct bonds of the constituent materials, or may alternatively be provided as metallic interlayer(s). The outer layers of heavier, more impact- and wear-resistant material are generally less thick than the intermediate layer comprising the lighter weight metallic material, and the outer layers are arranged to provide surfaces that experience high impact and relative movement. Slide component 20 may first be provided as a blank from a sheet of bonded multi-metallic material, as described above, and then machined to provide the desired three-dimensional structure and surface conformation, as shown.
[0043] FIGS. 4A-4C schematically illustrate multiple alternative embodiments of a firearm sear component fabricated from bonded multi-metallic base components having different structures and configurations. The sear component has wear points generally at the distal portion 31 of the component and at the central bore 33 . In the embodiment shown in FIG. 4A , sear component 30 A is fabricated from a bonded multi-metallic substrate material comprising at least three constituent metallic materials. In this embodiment, sections 32 and 34 are provided as different materials, each of the materials having generally wear- and impact-resistant properties, such as two different iron-containing metals, such as steel alloys or stainless steels. Section 36 experiences less wear during operation of the firearm and is provided as a lightweight material, such as an aluminum or titanium-containing metal. Bond interfaces are shown as bond lines 35 , 37 and, in this embodiment, the thickness of each of the constituent metallic layers is generally equivalent. Sear component 30 A may first be provided as a blank formed from a sheet of bonded multi-metallic material, and then may be machined to provide the desired three-dimensional structure and surface conformation.
[0044] FIGS. 4B and 4C schematically illustrate alternative embodiments of a firearm sear component fabricated from multi-metallic substrate materials comprising at least two constituent metallic materials. In the embodiment illustrated in FIG. 4B , sear component 30 B comprises section 38 formed from a material having wear- and impact-resistant properties, such a steel alloy or stainless steel material, with both wear points 31 and 33 being located in the sear component at a location within section 38 . Section 40 experiences less wear during operation of the firearm and is provided as a lightweight material such as an aluminum- or titanium-containing metal. The material interface is shown as bond line 39 . In this embodiment, the thickness of each of the constituent metallic layers is unequal, with the heavier, more wear- and impact-resistant metallic layer being thicker than the lighter weight metallic layer.
[0045] In the embodiment illustrated in FIG. 4C , sear component 30 C comprises section 42 formed from a material having wear- and impact-resistant properties, such a steel alloy or stainless steel material, and wear point 31 is located in the component at a location within section 42 . In this embodiment, section 44 may be provided as a different steel alloy or stainless steel material, or it may be provided as a lightweight material such as an aluminum- or titanium-containing metal, with wear point 33 being located in the component at a location within section 44 . The material interface is shown as bond line 43 . In this embodiment, the thickness of each of the constituent metallic layers is unequal, and the lighter weight metallic layer is thicker than the heavier, more wear- and impact-resistant metallic layer.
[0046] FIGS. 5A and 5B schematically illustrate multiple embodiments of a firearm hammer component fabricated from bonded multi-metallic materials having the same composition but having different bond line geometries and, therefore, different weight and configuration characteristics. The hammer component experiences a generally high impact zone in the area indicated generally by reference numeral 51 and has wear points generally at locations 52 , 53 and 54 . In the embodiment shown in FIG. 5A , hammer component 50 A is fabricated from a bonded multi-metallic substrate material comprising at least two constituent metallic materials. In this embodiment, section 56 is formed from a material having generally high wear- and impact-resistant properties, such as a steel or stainless steel material. Section 58 experiences less wear and impact during operation of the firearm and is provided as a lightweight material such as an aluminum- or titanium-containing metal. The bond interface is shown as bond line 57 . In this embodiment, the high impact area and all of the wear points are located in section 58 , formed from a wear- and impact-resistant metallic material. Hammer component 50 A may first be provided as a blank formed from a sheet of bonded multi-metallic material, with the pattern aligned to appropriately orient the bond line in the hammer blank and final hammer component. The blank may then be machined to provide the desired three-dimensional structure and surface conformation.
[0047] FIG. 5B schematically illustrates an alternative embodiment of a firearm hammer component 50 B fabricated from a bonded multi-metallic substrate material comprising at least two constituent metallic materials. In the embodiment illustrated in FIG. 5B , section 60 is formed from a material having generally high wear- and impact-resistant properties, such as a steel or stainless steel material. Section 62 experiences less wear and impact during operation of the firearm and is provided as a lightweight material such as an aluminum- or titanium-containing metal. The bond interface is shown as bond line 61 . In this embodiment, the high impact area and most, but not all, of the wear points are located in section 60 , formed from a wear- and impact-resistant metallic material. Hammer component 50 B may first be provided as a blank formed from a sheet of bonded multi-metallic material, with the pattern aligned to appropriately orient the bond line in the hammer blank and final hammer component. The blank may then be machined to provide the desired three-dimensional structure and surface conformation.
[0048] Exemplary firearms components comprising bonded multi-metallic materials are illustrated schematically and described in detail above. Those having skill in the art will recognize that these specific embodiments are illustrative and that many additional and alternative component designs may be conceived and implemented within framework of the invention disclosed herein. Any of the constituent metallic materials described herein may be used in any combination with other constituent metallic materials, and various firearms components may be configured, and fabricated, using various combinations of bonded multi-metallic materials. Additional firearms components that may be constructed using bonded multi-metallic base materials include: stocks; handles; gas tubes; extractors; sub-frames; receivers; barrels; bolts; blocks; doors; rollers; trunions; bushings; gudgeons; actuators; magazine wells; stops; various links and pins; various housing components; extractors; trigger mechanisms; safety mechanisms; firing chambers; grips; plungers; ejectors, sights, and the like.
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Firearms and firearm components are constructed from bonded multi-metallic base materials comprising at least two dissimilar metallic materials having different properties, such as weight, density, wear resistance, durability, hardness, and the like, bonded to one another. The components are fabricated such that the metallic material having higher impact- and wear-resistance is positioned at areas that experience impact, or that include bearing points, wear points, and interfaces with other components, while a lighter weight metallic material is positioned at component locations that don't have rigorous material property requirements. The bonded multi-metallic materials may be explosively bonded multi-metallic materials.
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BACKGROUND OF THE INVENTION
An increasing number of textile machines are provided with Jacquard devices for the production of fabrics with designs or ornamental motifs produced during the weaving or knitting phase by the selection of appropriate moving parts, according to the general principle of modifying the position and/or the path of the part in question (needle, jack or under-needle, sinker, heald, and similar). Essentially, a conscious discrimination is made between opposite positions and/or commands such as "inside-outside", "up-down", "north-south", and similar. In stocking and circular or flat knitting machines, with rotating cylinders and stationary cams or vice versa, the selection jack is usually provided with one or more butts against which an external device, actuator and/or selector acts. Normally, there is an impact between the latter and the stub of the incoming jack (in other words between moving and fixed parts or between moving parts only), the force of which varies with the operating speed and produces violent lateral impacts, vibrations, acceleration, heat, friction and wear in excess, which sometimes cause mechanical breakages. However, in addition to the said lateral impact, the normal selection is characterized by other limits which are even more evident in fast machines. One of these is represented by the necessity of widening the selection window or region, since, owing to the speed, the impact of the butts of the jacks on the raising cam must take place with a slight inclination, which may be less than 20 degrees. Another limit is set by the width of the selector (and the corresponding lateral inclined plane) which may be as much as 10 mm or more, this being necessary to allow the jack to complete its path, in other words to abruptly re-enter the cylinder or needle bed, passing behind the raising cam, without damage, in time. Another limit is represented by the fact that, after the impact with the external selector provided with the usual inclined plane, the jack violently re-enters towards the cylinder and is practically free, and therefore subject to strong recoils and vibrations. Another limit is represented by the fact that, independently of the operating speed, the normal width of the said selector complete with inclined plane does not permit the disposition of the jack butts very close together, for example, the use of a single selector of the actuator to select all the jacks, 13-13a, FIG. 21, in a similar way to the single-magnet device. A further limit is represented by the fact that electronic machines remain definitively characterized and conditioned by the original selection method, whether single-magnet device or actuators. Since each of these systems offers its own advantages, known to experts (rapid change of gauge, costs and wear of the materials, needle selection with two or three technical ways, and others), that a modern knitting factory must be flexible and rapidly adaptable to the changing market requirements with Jacquard and other types of production, it appears advantageous to have available a versatile machine capable of using, according to circumstances, various and/or different selection systems, or of producing different knitted structures at high speed.
SUMMARY AND OBJECTS OF THE INVENTION
On this assumption, a primary object of the present invention consists in the provision of a method and the corresponding equipment for Jacquard selection in a textile machine by means of a suitable and programmed frontal contraposition between moving parts and/or moving and fixed parts.
Another object consists in the reduction and/or elimination of many of the violent impacts, especially the lateral impacts, between moving parts and/or between moving and fixed parts. Another object consists in the elimination of the inclined plane of the selector or plunger, the point of impact and deviation for the incoming jacks and/or of the selector itself, which is replaced by appropriate extension of the keeper of the electromagnet and/or in any case the moving member-acting directly on the jack.
Another primary object consists in the provision of a method and the corresponding equipment for improving the selection with the jack and/or other similar part, even in the temporary "active preselection" position, in other words only partially on the raising cam and/or on its path.
Another object consists in the incorporation of the actuators and/or of other selection devices, with the corresponding cams for preselecting and/or for raising the jacks and/or under-needles and/or sinkers and/or needles in a single support for each feed or groups of feeds, with the further objective of replacement or rapid interchangeability with a similar support for different knit selections, or for high-speed textile operations. Another object consists in the predicted reduction of friction, heat and/or noise, in addition to lubrication, with more efficient and safe performance. An additional object consists in the provision of a method and the corresponding equipment for decreasing the width of the selection area to the nominal gauge or less, to guide the jacks appropriately and/or reduce their vibration and recoils during selection. Other objects will be revealed by the description, examples, drawings and claims, individually or as a whole.
These results may be achieved in various ways and the present description, which is purely descriptive and not restrictive, is centred by preference on the widespread system of electrical actuators acting from the outside on the butts of the incoming jacks.
The invention is defined by providing a needle bed with a plurality of mobile parts, such as jacks, for formation of fabric. The mobile parts are movable between an inner and an outer position with respect to the needle bed. A spring or other elastic structure is used to bias the plurality of mobile parts toward to the outer position. All of the plurality of the mobile parts are then sequentially moved towards the inner position by a pre-selection cam. Individual mobile parts are then selected to move in to the outer position by the biasing. This selecting is performed by a selector means which either allows the mobile part to move in to the outer position or blocks the mobile part from moving into the outer position. A raising cam then raises the selected mobile parts that are in the outer position. The non-selected mobile parts are kept disengaged or separate from the raising cam.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 shows an embodiment of an elastic jack;
FIGS. 2 and 3 show two views of a selection arrangement;
FIGS. 4, 5 and 6 show a further embodiment, in two operating conditions;
FIGS. 7 to 11 show a corresponding number of alternative embodiments;
FIG. 12 show an embodiment with an electromagnetic selector;
FIG. 13 show the movements of jacs and under-needle arranged therebelow;
FIG. 14 show the selection operated bymeans of permanent magnets;
FIGS. 15, 16 and 17 show a different embodiment of the jack, a mobile selector and a lifting cam;
FIG. 18 show an arrangement of pre-selection cams;
FIG. 19 show a different embodiment of a jack;
FIG. 20 show the operation of a lifting cam;
FIG. 21 show the operation of an oscillating selector;
FIG. 22 show the operation of a permanent magnet.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention is preferably applied with moving members such as jacks, needles, sinkers and similar, provided with individual and/or common springs, acting at the moment at which the said jack enters the critical selection position. The force, or pressure, is produced either by the temporary structural deformation of the jack (known as an elastic jack) and/or part of it, or by a separate and/or general spring, similar to those of the needle cylinders, or by a band of rubber and/or other suitable material, which may be filled with gas or liquid, capable of pushing back the jack by reaction. The latter may be of the type oscillating at the lower end from and towards the cylinder with a vertical undulating motion, 5 in FIGS. 15 and 19; or oscillating at the upper end, 1-1a in FIG. 1, possibly provided with a fork and/or zigzag which houses and/or controls the adjacent and/or overlying under-needle or sinker, 3 in FIG. 1; or a jack with both ends oscillating, like 1 in FIG. 9. In general, the said jacks, which are already outside the cylinder, in the pre-selection area are progressively guided and/or squeezed by at least one cam or inclined plane which may be also inserted in or fixed to the support of the actuator GA, FIG. 2. Moreover, the invention preferably uses known selection devices such as the said electrical actuators and others: electromechanical, magnetic, piezoelectric, ceramic, or pneumatic devices and/or linear motors; or selection wheels or pattern drums, groups of fixed or movable selectors for minijacks machines, and similar, characterized by positions, movements, rotations, oscillations, impulses or vibrations according to an operating and/or design program.
The invention preferably produces a "soft" approach, free of violent lateral impacts between the incoming jacks and the selectors disposed at the feeds. In one of the preferred embodiments, a selection jack, 1 in FIG. 1, is used, and oscillates at the upper end in position 1a; it is provided with cylinder or general springs such as M1, or individual springs such as M2, M3 and/or 21-22 in FIG. 8 (elastic jack). It is also provided with one or more selection butts 11 and the preselection butt 12, and is characterized by the presence of at least one under-needle or overlying member 3, guided and slidable in the direction of the arrow F, and provided in turn with at least one raising butt 13. At the operating and/or selection points, the said jack 1 is pushed by an inclined plane K2, FIGS. 2-3 (and 5-6-13), towards the 33 inside of the cylinder or needle bed, so that the butt 13 assumes the position 13a1, where it is completely excluded, or 13a, so that the point or edge of the butt 13 is disposed partially on the raising cam K fixed to the support 10. In the selection area corresponding to the butt 13a and 13a1 in FIG. 3, the movable selector or actuator L inserted in the corresponding actuator unit GA operates immediately after the cam K2. In the active position, L in FIG. 2, it acts on the selection butt 11 of the jack to prevent it from moving out. The jack 1, when freed from the constraining force of the cam K2, tends to move out under the force of the individual or general spring. In practice, therefore, the selector L acts as a stop, wall or limit, so that the jack continues its travel without modifying its trajectory or path. In the opposite case, the inactivity of the selector or actuator L1 in FIG. 2, housed in the actuator unit GA, does not interfere with the automatic outward movement of the jack which continues on the raising cam K in position 13b in FIGS. 2 and 3. The phases described are further illustrated in detail in FIGS. 5 and 6 in relation to the jack 1 of FIG. 4, provided with various spring(s) such as M1-M2-M3-M4 and a under-needle 3, which is vertically slidable in the direction of the arrow F and is structurally elastic at the point M5 if subjected to appropriate pressure and/or bending.
The jack 1 oscillating on the upper end is provided with selection butts 11, a preselection butt 12 and a raising butt 13, seen in plan view in FIG. 5. In the case in question, the cam K2 presses and progressively moves all the incoming butts 12w into the positions 12y and 12a. This movement naturally also affects the position of the under-needle above, whose butt 13w modifies its path, first at 13y and then at 13a. In this phase, the selector or actuator acting on the selection butts 11, in the selection area AS, remains inactive, in the position Ll. Consequently the butt 12a, pushed by its spring and/or other force, returns to its natural external position, preferably following the inclined exit plane of the cam K2, indicated by P.I. This movement obviously affects the position of the under-needle 13a above, which continues its travel on the raising cam K, as 13b, in a similar way to FIGS. 2 and 3. FIG. 6 differs from 5 in that it shows the active position of the selector or actuator L, which, being disposed in the selection area AS, performs different functions, according to the invention. The said selector L retains and/or maintains the corresponding butt 11a in its current position, in such a way that the butt above, 13a, remains constantly behind the line of the raising cam K as shown at 13c and in a similar way to 13a1 in FIG. 2. In other words, the said selector L, being also provided with a small frontal inclined plane, pushes the butt 11a (13a), which is already partially on the cam K or its path, further into the position 13c. To summarize, by coordinating the positions of the butts 11a, 12a, 13a with the preselection cam K2 and the function and/or frontal profile of the selector L, the Jacquard selection takes place in a linear way, the raising butt 13a being kept behind the cam K as shown at 13c; alternatively, the said selection is partially modified by the introduction of a temporary phase of "active preselection" characterized in that the raising butt 13a is disposed initially partially on the path of the raising cam K, and therefore properly advanced, but is otherwise ready to be pushed back again beyond and behind the raising cam K by the selector L, whose pressure or force overcomes the pressure or force of the jack. The inclined plane or cam K3 disposed immediately before the selectors L-L1 (FIGS. 5-6) preferably performs functions of protecting the selectors and in the case in question does not come into contact with the incoming butts (see also 12 and 12a in FIGS. 16 and 18). If any jacks break, this inclined plane guides any unexpected and uncontrolled incoming butt or fragment into the cylinder or needle bed; if isolated and connected suitably to the circuit of the stops, it also acts as a stop device in case of contact with unexpected metal parts. The invention substantially modifies the moving selector normally inserted in the cited selection devices or conventional actuator units, for example those with 8 levels, in at least two aspects, by separating and/or eliminating the lateral inclined plane, which is merely preparatory and is a cause of breakage, from the selector itself with the functions of pushing and guiding the butt of the jack in the cylinder or needle bed and holding it there, appreciably reducing the load and mass in movement so that even a conventional actuator benefits from this in terms of production and operating costs, with better and safer performance. In another preferred embodiment, the invention uses the jack 1, shown schematically in FIGS. 9-10-11, and differing from the preceding jack in that it is essentially hinged and/or pivoted in the middle lower part so that it oscillates at both ends. In FIG. 9, the jack 1 consists of the lower appendage 9 against which there acts an electromagnet 20 and/or a cam also formed by a permanent magnet MP on which the lower butt 10 runs. The jack 1 is pivoted at the point 30 on the needle cylinder or at the bottom of the slits or bars; it is provided with one or more cylinder springs mc capable of returning the said jack; finally the normal butts for selection 11, preselection 12 and raising 13 are present. FIG. 10 shows the jack 1 hinged at the point 26 on a fixing member inserted into the bars of the cylinder, which is not shown. The appendage 9 also follows the profiles of the adjacent inclined planes K6 and K7. In FIG. 11, the said jack differs further in that it is hinged at 3 to the member inside the cylinder 2, which is also provided with an elastic appendage 4. FIG. 13 is a plan view of the movements of the jacks and the under-needles above in the new and different configuration characterized by the jack 1 which oscillates at both ends. The preselection butts 12 encounter the inclined plane or cam K2 which diverts their path to 12y and 12a. The selector L, being inactive, does not hinder the return of the jack to the original position, and the raising butts 13, after a brief diversion to 13y and 13a, rise on the cam K. At the same time, the lower butt 10, having moved past the selection area AS, continues as at 10b. Otherwise, the selector L, being active, contains, retains and/or pushes the butt 11a, consequently moving the raising butts 13 (not shown) away behind the cam K. In this position, in FIG. 14, the lower butt 10, after the selection area AS, continues to be in contact with and/or attracted by the force of the permanent magnet MP. The configuration described is completed in a different embodiment with the use of the electromagnet 20 in FIG. 12, provided with a coil 21 which, when energized according to the operating program, momentarily removes the magnetic field through which pass the lower appendages 9 pre-loaded by the raising cam K4 up to the selection area 9A. Normally, the permanent magnetic field retains the said appendages and forces them to continue as at 9a; the momentary removal of the magnetic field in the selection area allows the appendage 9a to return to 9b, this being facilitated by the diverting cam K5. In a different embodiment of the invention, the jack 5 in FIG. 15, oscillating at the lower end with an undulatory motion, provided with spring(s) M1-M2-M3, a raising butt 8 and a selection butts 9 with a pointed lower end 7, is normally disposed in the position indicated by 7a-8a-9a in FIG. 18. In the preselection area, the jack 5 is pushed by the cam 14a and/or 14b (and/or 15a) which may be movable and/or adjustable from the outside by means of suitable control equipment, towards the needle bed so that the said parts 7a-8a-9a assume the inner positions 7b-8b-(8b1)-9b. In the case in question, the selector 13, in FIGS. 16-18, oscillating vertically and/or horizontally, acts as a stop, limit, or wall to the selection butt 9b, which is held there, and continues its travel as shown at 9d, 8d and 7d. With the selector 13 inactive, the butt 9b pushed by the spring and/or by combinations of pressure, 313 fulcrum or lever, or by an elastic jack provided with an appendage and/or zigzag capable of imparting to it an intrinsic structural elasticity, moves out, modifying its path abruptly at 9c, FIG. 18. Consequently, the parts 8 and 7 also assume the positions 8c and 7c, with the aid of the corresponding cams 16, KS and/or the corresponding selector and/or electromagnet. The resting or inactive position of the selector 13 allows the jack to move out, being pushed back by the spring, and then to rise on the corresponding cam KS as at 8c, also in FIG. 17. The selection is then achieved by means of the position of the selector 13 which prevents the selection butt 9b from moving out; alternatively, the unselected jacks move out of the cylinder automatically under the action of the individual or general springs. In the case in question, the lower part of the jack 7, being rather pointed, has the purpose of ensuring that the selection procedure takes place both by diverting the trajectory from 7b to 7c with the aid of the diversion cam 16 and by retaining the inactive jacks 7d with the additional aid of the permanent magnet MP adjacent to the selection area Z. An additional embodiment of the present invention is schematically illustrated by the jack 5 of FIG. 19 which differs from the similar jack in FIG. 15 in that it is structurally elastic at M, and is provided, if necessary, with another spring such as M1. This jack oscillates at the lower end, following the preselection cam KP, and is retained if necessary by the permanent magnet MP, both of these being disposed on the lower end 7 or otherwise, for example against the raising butt 8. Normally, the jack 5 follows the raising cam KS when the selection butts 9 are not pushed by the corresponding selectors, as indicated in FIG. 20. The incoming jack 7a-8a-9a is diverted to the interior of the needle bed to the position 7b-8b-9b, in the selection area and/or nominal gauge Z. The selector 13, being inactive in respect of 9b, does not impede the automatic outward movement of the jacks compressed previously, which follow the raising cam KS. Conversely, with the active selector L against the butt 9b, the butts 7b and/or 8b below remain behind the raising cam KS, being further attracted to and/or maintained in this position by the force of the adjacent permanent magnet MP, provided if necessary with a suitable inclined plane P.I. capable of facilitating the selection. It should be noted that the width of the said selector L may vary in accordance with the different gauges of the textile machine and/or in accordance with other technical requirements that may arise.
Another important object of the invention is achieved by modifying the position and/or the travel and/or the function of the selector 13 acting on the butts of the jacks, FIGS. 16-18-20-21, which is similar to L-L2 in FIGS. 2 and 3. According to the invention, the said selector oscillates laterally, in other words horizontally through the space which is necessary for the correct outward movement of the selected jack and/or in any case sufficient to prevent errors of selection. It is therefore possible to use the said selection members both for the initial design and by the different positioning of the electromagnet and/or other similar member, such as a piezo-ceramic strip, or the keeper of one or more electromagnets duly prepared and strengthened, oscillating at high speed for the individual selection of the jack, providing an alternative method to the conventional single-magnet device, and illustrated schematically in FIG. 21 at 13-13a hinged on 11 and acting on the selection butt 9b, which, being pushed into the cylinder, forces the corresponding butt 7b and/or 8b to follow the permanent magnet MP into position 7d in FIG. 22. The letters KP indicate optional preselection cams for the butts 7 and 8, while As indicates the selection area, comprising both the thickness of the selector 13 and the part of the path subject to the action of the permanent magnet MP, before the raising cam KS. The above description, which is necessarily schematic, is in any case subject to variations and/or additional embodiments, owing to the considerable flexibility of the invention. It is obviously applicable to Jacquard machines in general, including mechanical ones, but the invention is fully applicable in a machine initially provided with electronic selection, for example one with electrical actuators incorporated in a single support, complete with cams for the control of the jacks, under-needles, sinkers, and/or needles and subsequently capable of assuming different technical and textile characteristics according to the circumstances. Within the same industrial sector, for example that of knitted fabrics, the machine in question changes needle selection from two to three technical ways; from 48 to 60 or 72 feeds or vice versa with the predispositions and/or arrangements suitable for each case, as known to those skilled in the art. The present description is for guidance only: parts and/or functions may vary according to the multiple possible embodiments and/or applications included or falling within the concept and/or purposes of the invention.
BRIEF DESCRIPTION OF THE FIGURES
The relative simplicity of the invention, which will be evident to those skilled in the art, requires rather simple and schematic drawings. In Sheet 1, FIG. 1 shows the jack 1, oscillating as shown at la, provided with spring(s) M1 and M2, or M3, with the lower end 2, the selection butt 11, the preselection butt 12 and the raising butt 13 of the under-needle 3 inserted and guided vertically, as shown by the arrow F, in its housing. FIG. 2 shows in section the jack 1 against the actuator unit GA which houses the moving selector, active at L and inactive at L1 against the butts 11. The cam support 10 houses the preselection cam K2 against the butts 12 and the raising cam K for the butts 13, which are disposed behind the cam K at 13a1; are partially on the cam K at 13a; and are raised at 13b. FIG. 3 is a schematic frontal view of the cam K, the incoming butt 13a and/or 13a1, the butt 13c behind the cam K, and the butt 13b on its apex. The preselection cam K2 is in line with the actuator unit GA which houses the selector oscillating vertically L or oscillating horizontally as at L2. FIG. 4 shows the jack 1 provided with various springs M1-M2-M3-M4 and/or with the under-needle 3 which is structurally elastic at M5. FIG. 5 is a plan view of the three butts of the jack 1, co-ordinated with respect to the preselection cam K2, the raising cam K and the protection-preselection cam K3, with the selector L1 in the selection area AS. FIG. 6 differs from FIG. 5 in that it shows the non-selection of the butts 13c, caused by the action of the selector L against 11a.
In Sheet 2, FIGS. 7 and 8 show the jack 1 with the cylinder spring mc and some variants relating to the under-needle 3, as well as the presence of elastic zigzags or appendages 21 and 22 which are disposable in various ways. FIGS. 9, 10 and 11 show a different jack 1, essentially pivoted in the middle lower part 30, 26 and 3 so that both its ends oscillate. In relation to the different embodiments, this pivot is disposed directly against the cylinder 30 or provided by the functional connection of the jack 1 to other members (25-2) housed in the cylinder. The lower butt 10 is retained by a permanent magnet MP immediately following the selection area; alternatively the lower appendage 9 is also used for the selection with the single-magnet device 20 and with the aid of cams K6 and K7 in FIG. 10 and cams K4 and K5 in FIG. 12, where the energized coil 21 temporarily demagnetizes the bearing plane on which run the appendages 9 and 9a, which are diverted to the new position 9b. FIG. 13 is a plan view of the butts 10-11-12-13 of the said jack in relation to the preselection cam K2, the raising cam K, the control cam K3 and the 25 selector L, which is inactive in this case. If it is activated against 11a, the butts 13 pass behind the raising cam K, while the lower butts 10 are retained by the permanent magnet MP in the position 10a, as shown in FIG. 14. In Sheet 3, FIG. 15 shows a different type of jack 5, oscillating at the lower end 7, provided with spring(s) M1-M2-M3 and/or structurally elastic, provided with a raising butt 8, selection butts 9 and a preselection point or butt 7. FIG. 16 shows the moving selector 13 in the support or actuator unit 10, provided with an common inclined plane 12 and/or an individual inclined plane 12A. The said inclined plane 12, which is vertical, parallel to the cylinder, and continuous and/or segmented, protects the actuator and/or the individual selectors from any broken jacks, with the further function of a stop device in case of contact with these jacks. When suitably disposed, it becomes a preselection cam similar to 14a and 15a in FIG. 18. The vertical, lateral or horizontal position or displacement of the selector 13 permits the automatic expulsion of the jack 5 from the needle bed. FIG. 17 is a frontal view of the raising cam KS in relation to the incoming raising butt 8b, which rises as at 8c, or remains behind the cam KS in the position 8d. FIG. 18 is a plan view of the position of the incoming butts 7-8-9 at 7a-8a-9a, up to the selection area 7b-8b-9b from which they are diverted as at 7c-8c-9c or continue as at 7d-8d-9d. The lower butt or appendage 7, having passed the selection area Z, continues to be retained by the contact with the permanent magnet MP, with evident advantages. The jack 5 shown in FIG. 19 differs from the similar jack in FIG. 15 in that it is structurally elastic at M, and is also provided, if necessary, with another spring such as M1. Its lower end oscillates, following the preselection cam KP, and is retained if necessary by the permanent magnet MP, both of these being disposed at the lower end 7. It is provided with the butt 8 for the raising cam KS and selection butts 9. Its functions are shown schematically in FIG. 20: the incoming jack 7a-8a-9a is diverted inwards to the position 7b-8b-9b, the selection area Z. The selector 13, being inactive against 9b, does not impede the automatic outward movement of the compressed jacks which meet the raising cam KS. Conversely, with the selector L acting against the butt 9b, the butt 7b and/or 8b remains behind the raising cam KS, being attracted and/or maintained where specified by the force of the adjacent permanent magnet MP, which, being provided also with inclined plane(s) P.I., performs functions of active selection, in other words such that it modifies the path of the jack, removing it from the raising cam KS, contributing to a reduction in the selection area Z to the nominal gauge, or to the reduction of the width of the horizontally oscillating selector as shown at 13-13a in FIG. 21, hinged at 11 and acting against the butt 9b, which, being pushed into the cylinder, forces the corresponding butt 7b and/or 8b to follow the permanent magnet MP to position 7d in FIG. 22. Finally, the letters KP indicate two different preselection cams, for the butts 7 arid/or 8, while AS indicates the selection area, comprising both the thickness of the selector 13 and the part of the path subject to the action of the permanent magnet MP before the raising cam KS.
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The invention relates to Jacquard selection in a textile machine characterized by a selection jack (1) provided with a spring (M1) by which, after the preselection phase in which the jacks are guided by a cam inside the cylinder, they move out under the pressure of the spring, thus modifying the path or the functions; or remain contained and/or retained in the cylinder by a selector and/or other member disposed frontally which prevents their moving out. According to circumstances, the selector, even if fixed, can move vertically, horizontally and also radially, with minimum time and space, without lateral impact on the incoming butts and/or jacks. Finally, the actuators, together with the cams of the jacks and/or needles, are incorporated in a modular support to modify the type of selection and/or for textile operations other than the Jacquard type.
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The present invention is a divisional application claiming the benefit of U.S. patent application Ser. No. 12/081,984 filed on Apr. 24, 2008, now U.S. Pat. No. 7,741,094.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a protein isolated from Coprinus clastophyllus , especially to a protein isolated from Coprinus clastophyllus and having prolyl oligopeptidase activity, the isolated gene sequence thereof, method for producing and use of the same.
2. Description of the Prior Art
Prolyl oligopeptidase (EC 3.4.21.26), also known as prolyl endopeptidase or post-proline cleaving enzyme, cleaves proline containing polypeptides at the carboxyl side of a proline residue (Polgár, Methods Enzymol. 244:188-200; Polgár, Cell. Mol. Life Sci. 59:349-362).
Prolyl oligopeptidase is widely researched in recently in several application fields. Prolyl oligopeptidase degrades peptides involving memory and learning and thus considered to be connected with amnesia and conditions of degradative memory, including Parkinson's disease. Inhibitants for prolyl oligopeptidase are currently being researched to find therapies thereof (Yoshimoto et al., J. Pharmacobio-Dyn. 10:730-735; Atack et al., Nat. Prod. Res. 19:13-22; Marighetto et al., Learn Mem. 7:159-169; Lee et al., Planta Med. 70:1228-1230; Sorensen et al., Nahrung 48(1):53-56; Atta-ur-Rahman et al., Nat. Prod. Res. 19:13-22; Jarho et al., J. Med. Chem. 48:47772-4782). Researches in other application fields include: using prolyl oligopeptidase as a treatment for celiac disease caused by proline abundant gluten (Piper et al., J. Pharmacol. Exp. Ther. 311:213-219; Marti et al., J. Pharmacol. Exp. Ther. 312:19-26; Matysiak-Budnik et al., Gastroenterol. 129(3):786-796; Pyle et al., Clin. Gastroenterol. Hepatol. 3(7):687-94; Gass et al., Biotechnol. Bioeng. 92(6):674-84); purification and recovery of exogenously expressed peptides (Xiu et al., Biotechnol. Appl. Biochem. 36(Pt2):111-117); and development of a cancer-treating prodrug being less toxic to cells and will be converted by prolyl oligopeptidase to a functional drug (Heinis et al., Biochemistry 43:6293-6303).
Prolyl oligopeptidases found in animals, plants and microbes generally display relatively low activities. Some know prolyl oligopeptidases found in microbes include those originate from: Flavobacterium meningosepticum (having an activity of 0.30 U/ml according to Yoshimoto et al., J. Biol. Chem. 255:4786-4792); lactobacillus casei (having an activity of 0.15 U/g according to 6. Habibi-Najafi et al., J. Dairy Sci. 77:385-392); Propionibacterium freudenreichii (having an activity of 4.3 mU/ml according to Tobiassen et al., J. Dairy Sci. 79:2129-2136); a fermented broth of Agaricus bisporus (having an activity of 0.15 U/ml according to Abdus Sattar et al., J. Biochem. 107:256-261); and Xanthomonas spp. (having an activity of 0.15 U/ml according to Szwajcer-Dey et al., J. Baceteriol. 174:2454-2459).
Enzymatic activity of prolyl oligopeptidase may be increased by genetic engineering methods, specifically, cloning a prolyl oligopeptidase gene into host cells such as E. coli ( Escherichia coli ) followed by exogenous large-scale expression. Prolyl oligopeptidase originally from Shingomonas capsulata exhibited 7-fold higher activity of 0.2 U/ml in E. coli (Yoshimoto et al., Japanese patent JP10066570). A Flavobacterium meningosepticum prolyl oligopeptidase gene encoded protein expressed in E. coli exhibits maximal activity of 0.7 U/ml (Diefenthal et al., Appl. Microbiol. Biotechnol. 40:90-97). A Flavobacterium meningosepticum prolyl oligopeptidase reconstructed by Uchiyama in E. coli exhibits maximal activity of 8.1 U/ml, which further demonstrates specific activity as high as 124 U/mg after purification (Uchiyama et al., J. Biochem. 128:441-447). An Aeromonas hydrophila prolyl oligopeptidase expressed in E. coli exhibits activity of 1.48 U/ml which is 100 fold higher than expressed in original Aeromonas hydrophila strain and exhibits specific activity up to 8.8 U/mg after purification (Kanatani et al., J. Biochem. 113:790-796). An Aeromonas punctata prolyl oligopeptidase expressed in E. coli has 112 fold higher activity than that expressed in original strain and exhibits specific activity up to 67 U/mg after purification (Li et al., Wei Sheng Wu Xue Bao. 2000 40(3):277-283).
In addition, a Pyrococcus furious prolyl oligopeptidase gene encoded protein expressed in E. coli exhibits specific activity of 232 U′/mg (the activity units being alternatively defined and calculated as 1 U′ being equal to 0.1 OD 410 per minute by Harwood et al., J. Bacterol. 179:3613-3618 and different from that in aforementioned literatures) and 4 U/mg (Harwood and Schreier et al., Methods Enzymol. 330:445-454) after purification.
Aforementioned examples demonstrate that purified prolyl oligopeptidases expressed in E. coli have higher activity. However, prolyl oligopeptidases of different origins have preferences for interaction conditions. Optimum conditions enable a prolyl oligopeptidase to display full activity; otherwise, only partial activity may be attained. A highly active prolyl oligopeptidase has more potential for use if its optimum conditions are similar to practical conditions where it is applied. When evaluating the potential of a prolyl oligopeptidase in such aspect, optimum temperature and optimum pH are considered. Furthermore, ranges of optimum conditions are defined by retained activity under optimum generic environmental conditions. For example, heat stability is determined by measuring the ratio of retained activity after heating to full activity.
Each of the aforementioned prolyl oligopeptidases have corresponding optimum conditions. The optimum conditions for Aeromonas hydrophila prolyl oligopeptidase are 30° C. and pH 8.0. When preheated at 42° C. for 30 minutes, 50% activity is retained. The activity of an Aeromonas punctata prolyl oligopeptidase reaches optimum activity at 34° C. and pH 8.4. The optimum pH and temperature for Flavobacterium meningosepticum prolyl oligopeptidase are 7.0 and 40° C.; and its activity will be reduced to 50% when heated to 42° C. for 15 minutes (Yoshimoto et al., J. Biol. Chem. 255:4786-4792). When heated at 60° C. for 1 hour, the activity of a Flavobacterium meningosepticum prolyl oligopeptidase mutated with error-prone PCR mutagenesis drop to 50% under conditions of pH7.0 and 30° C. (Uchiyama et al., J. Biochem. 128:441-447). Of all prolyl oligopeptidases expressed in E. coli, Flavobacterium meningosepticum prolyl oligopeptidase exhibits the highest specific activity and showed the best heat stability after mutagenesis with error-prone PCR. However, since Flavobacterium meningosepticum is a pathogen, safety concerns arise for use, despite other prolyl oligopeptidases exhibiting lower heat-stability.
Nevertheless, to find and isolate a prolyl oligopeptidase corresponding to human usage from various organisms requires much research and experimentation for those generally skilled in the art of the present invention. This difficulty was compounded when the prolyl oligopeptidase found in the first screening of Aspergillus niger was later authenticated to be another serine protease. Though certain basidiomycete was known to have prolyl oligopeptidase, there are no filamentous fungi known to have prolyl oligopeptidase so far. As a result, no prolyl oligopeptidase of fungal original has been expressed in E. coli in large scale.
To overcome the shortcomings of available prolyl oligopeptidases, the present invention provides a protein having prolyl oligopeptidase activity, a nucleic acid encoding thereof and methods for producing and using the same to mitigate or obviate the aforementioned problems.
SUMMARY OF THE INVENTION
The present invention relates to proteins isolated from Coprinus clastophyllus having prolyl oligopeptidase activity, nucleic acids encoding the protein and methods for producing and using the protein.
One aspect of the present invention is to provide an isolated protein selected from the group consisting of:
(a) a protein comprising the amino acid sequence of SEQ ID NO:6 or SEQ ID NO:10;
(b) a protein encoded by a nucleic acid of the sequence of SEQ ID NO:5 or SEQ ID NO:9;
(c) a protein comprising the function of protein (a) or protein (b), and comprising an amino acid sequence having a similarity greater than 60% to the amino acid sequence of protein (a) or protein (b);
(d) a protein comprising the function of protein (c), and encoded by a nucleic acid of a sequence having a similarity greater than 60% to the sequence of SEQ ID NO:5 or SEQ ID NO:9;
(e) a protein encoded by a nucleic acid being able to hybrid to a nucleic acid of the sequence of SEQ ID NO:5 or SEQ ID NO:9 under a highly-strict condition comprising acts of allowing interaction at 50° C. for 16 hours; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; repeating the preceding act once; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes; and repeating the preceding act once.
Another aspect of the present invention is to provide isolated nucleic acids selected from the group consisting of:
(a) a nucleic acid encoding the aforementioned protein;
(b) a nucleic acid of the sequence of SEQ ID NO:5 or SEQ ID NO:9;
(c) a nucleic acid encoding a protein as that encoded by nucleic acid (b), and of a sequence having a similarity greater than 60% to nucleic acid (b);
(d) a nucleic acid being able to hybrid to a nucleic acid of the sequence of each of nucleic acid (a)-(c) under a highly-strict condition comprising acts of allowing interaction at 50° C. for 16 hours; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; repeating the preceding act once; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes; and repeating the preceding act once;
(e) a nucleic acid encoding a protein comprising a amino acid sequence identical to the amino acid sequence of the protein encoded by each of nucleic acids (a)-(d); and
(f) a nucleic acid of the complementary sequence of each of nucleic acid (a)-(e).
The present invention also relates to nucleic acid probes, chimeric genes, nucleic acid constructs, vectors, transformants, pharmaceutical compositions, composition for use with a proline containing prodrug, as well as use of the aforementioned protein.
Another aspect of the present invention provides methods for producing a protein having prolyl oligopeptidase activity comprising (a) providing the aforementioned transformant; (b) culturing the transformant in a condition allowing expression of a protein having prolyl oligopeptidase activity; and (c) purifying and acquiring the protein.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a line graph of prolyl oligopeptidase activities of proteins pProHN14 and pProHN17 versus pH values wherein solid circles represent the pProHN14 protein and solid triangles represent the pProHN17 protein;
FIG. 2 is a bar chart of the prolyl oligopeptidase activities of proteins pProHN14 and pProHN17 versus temperature at pH 7.0 wherein black bars represent the pProHN14 protein and white bars represent the pProHN17 protein;
FIG. 3 is a bar chart of the prolyl oligopeptidase activities of proteins pProHN14 and pProHN17 versus temperature at pH 8.0 wherein black bars represent the pProHN14 protein and white bars represent the pProHN17 protein;
FIG. 4 is a broken line graph of heat stabilities of recombinant prolyl oligopeptidase wherein solid lines represent the pProHN14 protein, dotted lines represent the pProHN17 protein and shapes represent a temperature of preheated treatment, respectively being: circles representing 30° C., squares representing 37° C., triangles representing 45° C. and diamonds representing 55° C.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Definitions
Identity: The term “identity” is defined herein as the invariant extent between two nucleic acid sequences or that between two amino acid sequences. In the context of the present invention, “identity” refers to the “Identity” score when comparing two sequences (nucleic acid or amino acid) with Gap program (Genetics Computer Group, Version 11.1), wherein gap creation penalty=8 and gap extension penaly=2.
Similarity: The term “similarity” is defined herein as the extent of relatedness between two nucleic acid sequences or that between two amino acid sequences. The similarity between two sequences can be obtained from, the ratio of identity or conservation between the two sequences, or both. In the context of the present invention, “similarity” refers to the “Similarity” score when comparing two sequences (nucleic acid or amino acid) with Gap program (Genetics Computer Group, Version 11.1), wherein gap creation penalty=8 and gap extension penaly=2.
Chimeric gene: The term “chimeric gene” is defined herein as a gene formed by a recombinant nucleic acid carrying nucleic acids of different origins. For example, a chimeric gene may be formed by a recombinant nucleic acid carrying nucleic acids of different genes, or recombined nucleic acids of different gene fragments.
Control sequence: The term “control sequence” is defined herein as a nucleic acid sequence defining the on or off states of a gene and controlling the expression of the nucleic acid thereof.
Vector: The term “vector” is defined herein as a vehicle transferring a nucleic acid molecule into a host cell, which may be a plasmid, a phage or a virus. Such vectors include but are not limited to expression vectors that routinely accept nucleic acid molecules with recombinant nucleic acid sequences and induce the expression of the nucleic acid sequence after transferring the nucleic acid molecules into a host cell. Corresponding vectors for a host cell are determined by the vector-cell compatibility. Furthermore, the aforementioned plasmid may be a linear or a closed circular nucleic acid molecule.
DETAILED DESCRIPTION OF THE INVENTION
Prolyl oligopeptidase is researched for having valuable potentials such as to degrade peptides involving memory and learning, to be used as a treatment for celiac disease caused by proline abundant gluten, to purify or recover exogenously expressed peptides and may be used as a helping agent for cancer-treating prodrugs.
In the present invention, proteins with prolyl oligopeptidase activity and gene sequences thereof are described. Data relevant to the producing of said protein and substantial practical acts are also provided. The protein provides high enzymatic activity and a range of optimum conditions suitable for various applications.
In another aspect of the present invention, the isolated prolyl oligopeptidase gene from Coprinus clastophyllus is demonstrated being used in pharmaceutical applications with methods disclosed herein.
The aforementioned protein with prolyl oligopeptidase activity can be used as a treatment for celiac disease caused by proline abundant gluten, as a helping agent for cancer-treating prodrugs or for purifying and recovering exogenously expressed peptides.
The nucleic acids, vectors and transformants relevant to the aforementioned protein and methods are also disclosed.
It will be understood by those skilled in the art that various modifications, such as minor variations of concentrations or activities of produced prolyl oligopeptidases may be made to the present invention without departing from the spirit and scope of the invention. Furthermore, the present invention is not limited to the examples described herein but may also encompasses any and all embodiments within the scope of the present invention. It is also to be understood by those skilled in the art that alternatively available biological methods and techniques may be applied without departing from the scope of the invention.
Proteins
The present invention relates to isolated proteins having prolyl oligopeptidase activity. Prolyl oligopeptidase cDNAs are cloned from previously isolated Coprinus clastophyllus strain (deposition number: BCRC 36074; Bioresource Collection and Research Centre, Food Industry Research and Development Institute, Taiwan) having heat-stable prolyl oligopeptidase (extrocellular activity 0.03 U/ml). To further raise the prolyl oligopeptidase activity, E. coli was used as a host cell to hold the cloned prolyl oligopeptidase cDNA for large-scale expression in order to obtain functional amounts of the protein.
As defined herein, 1 U of prolyl oligopeptidase activity is the capability to produce 1 μmole of p-nitroaniline per minute. In a preferred aspect, the intracellular prolyl oligopeptidase activity of the protein is 7.2 U/ml, in another preferred aspect, 7.7 U/ml. The protein may be purified. The specific activity of the purified protein may be 55.0 U/mg to 70.0 U/mg. In a more preferred aspect, the specific activity of the purified protein may be 56.1 U/mg to 70.0 U/mg. In another preferred aspect, the specific activity of the purified protein may be 56.1 U/mg or 66.8 U/mg.
The optimum pH value for the protein may be pH 6 to pH 8. In a preferred aspect, the optimum pH value for the protein may be pH 6 to pH 7 and in a most preferred aspect, the optimum pH value for the protein may be pH 7. The optimum temperature for the protein at pH 7 may be 45° C. The optimum temperature for the protein at pH 8 may be 37° C.
In a preferred aspect, the protein contains an amino acid sequence having a similarity greater than 60% to the sequence of SEQ ID NO:6 or SEQ ID NO:10 or is encoded by a nucleic acid of a sequence having a similarity greater than 60% to the sequence of SEQ ID NO:5 or SEQ ID NO:9. In another preferred aspect, the similarities of the amino acid sequence or the nucleic acid sequence are greater than 70%. In a more preferred aspect, the similarities of the amino acid sequence or the nucleic acid sequence are greater than 80%. In an even more preferred aspect, the similarities of the amino acid sequence or the nucleic acid sequence are greater than 90%. In a most preferred aspect, the similarities of the amino acid sequence or the nucleic acid sequence are greater than 95%. It is understood by those skilled in the art that there may be variations between the aforementioned proteins in accordance with the present invention without abolishing the prolyl oligopeptidase activities thereof. Thus, it is also understood by a person skilled in the art that varying proteins having the aforementioned prolyl oligopeptidase activity are also covered within the scope of the present invention. In another most preferred aspect, the protein has an amino acid sequence comprising SEQ ID NO:6 or SEQ ID NO:10 or is encoded by a nucleic acid containing the sequence of SEQ ID NO:5 or SEQ ID NO:9.
In another preferred aspect, the protein has the function of the aforementioned protein and is encoded by a nucleic acid of a sequence having a similarity greater than 60% to the sequence of SEQ ID NO:5 or SEQ ID NO:9.
In another preferred aspect, the protein has the function of the aforementioned protein and is encoded by a nucleic acid wherein the nucleic acid hybrids to another nucleic acid of the sequence of SEQ ID NO:5 or SEQ ID NO:9 under highly-strict conditions comprising acts of allowing interaction at 50° C. for 16 hours; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes.
Nucleic Acids
The present invention also relates to isolated nucleic acids of sequences encoding the aforementioned proteins. In a preferred aspect, the nucleic acid is a nucleic acid of a sequence having a similarity greater than 60% to the sequences of SEQ ID NO:5 or SEQ ID NO:9 and encodes a protein having the prolyl oligopeptidase activity as that of the aforementioned protein. In another preferred aspect of the present invention, the similarity of the sequence of the nucleic acid with the sequences of SEQ ID NO:5 or SEQ ID NO:9 is greater than 70%; in an more preferred aspect the similarity is greater than 80%; in a even more preferred aspect the similarity is greater than 90%; in a most preferred aspect the similarity is greater than 95%. In another most preferred aspect, the sequence of the nucleic acid comprises SEQ ID NO:5 or SEQ ID NO:9.
It is to be understood by those skilled in the art that there may be variations between the sequence of SEQ ID NO:5 or SEQ ID NO:9 and the sequences of aforementioned nucleic acids. Each of the nucleic acid variants encodes a protein having prolyl oligopeptidase activity expressed by the sequences of SEQ ID NO:6 or SEQ ID NO:10, or of a sequence having a considerable similarity to the sequences of SEQ ID NO:6 or SEQ ID NO:10. Thus a person with general skill in the art can easily understand that those nucleic acids are within the scope of the present invention as long as the function of the encoded protein will not be abolished by the sequence variations.
Those skilled in the art will also understand that nucleic acids encoding a protein of the same amino acid sequence of that of the proteins encoded by the aforementioned nucleic acids is within the scope of the present invention. Furthermore, nucleic acids of complementary (antisense) sequences do not depart from the spirit and scope of the present invention.
Nucleic Acid Probes
The present invention also relates to nucleic acid probes that hybrid to the aforementioned nucleic acids under highly strict conditions comprising acts of: allowing interaction at 50° C. for 16 hours; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes; allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes.
Chimeric Genes
The present invention also relates to chimeric genes comprising the aforementioned nucleic acids being operably linked to a promoter allowing expression in a host cell. In an application of a research or commercial purpose, the skill necessary to operably link a nucleic acid and a promoter to achieve the purpose is well understood by those skilled in the art of the present invention.
Nucleic Acid Constructs and Vectors
The present invention also relates to nucleic acid constructs comprising the aforementioned nucleic acids being operably linked to a control sequence allowing the expression of the protein encoded by the nucleic acid in a host cell. Such nucleic acid constructs, such as recombinant plasmids, are widely applied in research or commercial fields. Building a nucleic acid construct containing a specific nucleic acid is understood and practicable to a person with general skill in the art.
The present invention also relates to vectors comprising the aforementioned nucleic acids or the aforementioned nucleic acid constructs.
Transformants
The present invention also relates to transformants being a host cell holding nucleic acids in accordance with the present invention wherein the host cell is transformed by accepting the aforementioned nucleic acids. The host cell may be an E. coli cell. For example, the host cell may be an E. coli cell of BL21(DE3) strain or DH10B strain. In another preferred aspect of the present invention, the prolyl oligopeptidase cDNA is operably linked to a promoter or a control sequence allowing expression in a host cell to form a chimeric gene or a nucleic acid construct. The chimeric gene or nucleic acid construct is able to express the cDNA in a host cell.
Compositions
The present invention also relates to compositions, such as pharmaceutical compositions. The compositions comprise the aforementioned protein in accordance with the present invention as a functional component. Prolyl oligopeptidase is known to be used as a treatment for celiac disease caused by proline abundant gluten. In addition, the range of the optimum conditions of the protein having prolyl oligopeptidase in accordance with the present invention covers conditions not covered by optimum conditions of known prolyl oligopeptidases, and is suitable for use under such conditions. As a functional component of the aforementioned composition, the protein effectively allows the purpose of the composition to be achieved. In an aspect of the present invention, the composition also comprises an excipient allowing the composition to be made as a solid matter, a semi-solid matter or a liquid matter.
The composition in accordance with the present invention may also be used with a prodrug containing proline residues. The composition for use with the proline-containing prodrug has at least one pharmaceutically acceptable excipient and the aforementioned protein. Having prolyl oligopeptidase activity, the protein is used as a functional component for converting the prodrug to a functional drug. In a preferred aspect, the composition further comprises an antibody conjugated with the aforementioned protein. The antibody is used to anchor the protein in a target tissue of an organism. When the prodrug is later administered into the circulatory system of the organism, the protein will only interact with the prodrug delivered to the target tissue. With the prolyl oligopeptidase activity of the protein, the prodrug will be converted into a functional drug in the target tissue, which significantly raises the selectivity and accuracy of the prodrug.
Use of the Aforementioned Protein
One aspect of the present invention relates to using the aforementioned protein. With the prolyl oligopeptidase activity, the protein can be used to process exogenously expressed peptides for recovering or be used in the manufacture of a purification reagent thereof.
Methods for Producing a Protein Having Prolyl Oligopeptidase Activity
The present invention also relates to methods for producing proteins having prolyl oligopeptidase activity. The method comprises providing the aforementioned transformant; culturing the transformant in a condition allowing expression of a protein having prolyl oligopeptidase activity; and purifying and obtaining the protein. The host cell includes, but is not limited to, a transformed cell of BL21(DE3) E. coli strain or DH10B E. coli strain.
EXAMPLES
The following experimental designs are illustrative, and are not intended to limit the scope of the present invention. Reasonable variations, such as those occurring to a person reasonably skilled in the art can be made herein without departing from the scope of the present invention.
Example 1
Construction of Coprinus clastophyllus cDNA Library and Cloning of Prolyl Oligopeptidase cDNA
1. Cloning of Coprinus clastophyllus Prolyl Oligopeptidase Gene Fragments and Preparation of Probes
Fungal genomic sequences were searched on NCBI web site by BLAST with the amino acid sequence of human prolyl oligopeptidase. Polymerase chain reaction (PCR) primers Pro16 and Pro17 were designed from regions of the genomes of Coprinopsis cinerea okayama7#130 and Phanerochaete chrysosporium RP-78 where high similarity to the prolyl oligopeptidase sequence was observed and have been attached, respectively as:
Pro16:
5′-tacggcggmt tcascatctc-3′
(SEQ ID NO: 1)
Pro17:
5′-tgccaytcyt cwccraactc-3′
(SEQ ID NO: 2)
The genomes of Coprinopsis cinerea okayama7#130 and Phanerochaete chrysosporium RP-78 are publicly available in databases maintained by the U.S. National Center for Biotechnology Information (Bethesda, Md.).
PCR was carried out using PCR primers Pro16 and Pro17 and genomic DNA of Coprinus clastophyllus as a template. 50 μl of mix solution for PCR comprises 1×PCR buffer, 0.2 mM of dNTP, 1 μM of Pro16, 1 μM of Pro17, 5 U of pfu DNA polymerase (Roach) and the template (genomic DNA of Coprinus clastophyllus ). PCR was carried out with ABI 9700 thermocycler (Applied Bioscience) and the following PCR program.
PCR program:
94° C., 3 minutes [1 repeat];
94° C., 30 seconds, 64° C., 30 seconds, 72° C., 1 minute [5 repeats];
94° C., 30 seconds, 60° C., 30 seconds, 72° C., 1 minute [5 repeats];
94° C., 30 seconds, 56° C., 30 seconds, 72° C., 1 minute [35 repeats];
72° C., 7 minutes [1 repeat].
A 128 by (base pair) fragment was amplified using PCR. The amplified fragment was then cloned into a PCR®2.1-TOPO vector (Invitrogen) to obtain a plasmid referred to as ‘p128’.
Two primers Pro20 and Pro21 were designed from p128. A probe was made from the Pro20 and Pro21 primers with PCR DIG Labeling Kit (Roche) following the manual of the kit. A PCR program was used in making the probe.
Pro20:
5′-tacggcggat tcagcatctc-3′
(SEQ ID NO: 3)
Pro21:
5′-tgccactcct caccaaactc-3′
(SEQ ID NO: 4)
PCR program:
94° C., 3 minutes [1 repeat];
94° C., 30 seconds, 58° C., 30 seconds, 72° C., 40 seconds [35 repeats];
72° C., 7 minutes [1 repeat].
2. Cultivation of Strains
Coprinus clastophyllus was cultured in YMA plate (Difco, No. 0712) at 25° C. for 18 days and then transferred to medium N at 25° C. and shaken at 200 rpm for 7 days. Medium N was adjusted to pH6 and comprised 2% glucose (Merck), 0.3% soybean flour, 1% Tryptone, 0.3% KH 2 PO 4 (Merck) and 0.1% MgSO 4 (Merck).
3. Building Coprinus clastophyllus cDNA Library
1.2 g of dehydrated mycelium was taken on day 7 of the aforementioned Coprinus clastophyllus cultivation and total RNA was extracted with TRIZOL (Invitrogen) according to the operation process provided therewith.
325 μg of Coprinus clastophyllus total RNA was obtained wherein the ratio of OD 260 /OD 280 was 2.05. The amount of total RNA to be extracted may be up to 500 μg.
An mRNA isolation kit, such as PolyATtract® mRNA Isolation Systems Kit provided by Promega, was used to extract mRNA from the total RNA according to the operation process provided with the kit. 6 μg of mRNA (with polyA) was obtained, wherein the ratio of OD 260 /OD 280 was 2.01. The aforementioned PolyATtract® mRNA Isolation Systems Kit primarily comprises 50 μl Biotinylated Oligo(dT) Probe (50 pmol/μl), 2.8 ml 20×SSC Solution (2×1.4 ml), 9 ml Streptavidin MagneSphere® Paramagnetic Particles (15×0.6 ml), 50 ml Nuclease-Free Water (2×25 ml), 1 each MagneSphere® Magnetic Separation Stand for 1.5 ml. The forementioned mRNA extraction was carried out with magnetic separation technology (MagneSphere® technology). Other mRNA isolation kits being able to extract mRNA from total RNA may also be employed.
ZAP-cDNA® Gigapack® III Gold Cloning Kit (Stratagen) was used according to operation process provided therewith. DNA fragments having lengths within 0.75-3 kb were collected as cDNAs with the ZAP-cDNA® Gigapack® III Gold Cloning Kit. 8×10 5 plasmid-carrying plaques were screened as a collection of strains defining a Coprinus clastophyllus cDNA library.
Different plasmids were respectively carried by the strains in the Coprinus clastophyllus cDNA library. Each plasmid comprised at least one vector and at least one cDNA. Each of the at least one vector comprised multiple restriction sites. The multiple restriction sites at least include EcoRI and HindIII sites. In addition, the sequences of regions flanking the two ends of the cDNA respectively correspond to T3 primer and T7 primer.
4. Plaque Selection
Plaque hybridization was carried out according to the following operation process of ZAP-cDNA® Gigapack® III Gold Cloning Kit to obtain multiple plaques formed with helper phage. A plaque lift was made with nitrocellulose membrane.
The plaque lift was first prehybridized in a Southern-blot hybridization solution such as the FastHyb solution (Biochain) at 50° C. for 2 hours and then undergones hybridization in a probe-containing FastHyb solution at 50° C. for 16 hours.
The plaque lift was then washed as follows:
(1) washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes;
(2) repeating act (1) washing with a solution having 2×SSC and 0.1% SDS at room temperature for 5 minutes once;
(3) allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes; and
(4) repeating act (3) allowing interaction in a solution having 0.5×SSC and 0.1% SDS at 65° C. for 15 minutes once.
The DIG antibodies conjugated with the probes were then detected after washing the plaque lift. The detection was visualized on X-ray films with autoradio development signals to identify plaques.
5. Obtaining Transformant
With the aforementioned process, 93 significant signals were identified. A secondary selection was carried out using ZAP-cDNA® Gigapack® III Gold Cloning Kit according to its operation process to further screen a pure single plaque. T3 primer and T7 primer were used to obtain PCR products from the plaques. PCR products having first 11 largest molecular weight were amplified from 11 plaques. The 11 plaques were selected and processed with in vivo excision.
The plasmid obtained from the 11 plaques were confirmed with EcoRI and HindIII restriction enzymes and then analyzed with gel electrophoresis. 4 longest plasmids, 49-1, 71-1, 76-3 and 91-1, were picked for producing transformants.
6. Sequencing
The lateral region of cDNA carried by aforementioned plasmids were first sequenced using available primers such as T3 and T7. Primers were further designed from sequences of lateral regions to sequence nested regions to complete the full length of the cDNA.
7. Obtaining and Confirming Coprinus clastophyllus Prolyl Oligopeptidase cDNA
The nucleic acid sequence of Coprinus clastophyllus prolyl oligopeptidase cDNA (SEQ ID NO:5) shows that the full length is 2508 nt (nucleotides) and a 2217 nt long ORF (open reading frame) (SEQ ID NO:6) starts at 65 th nt of the cDNA. The ORF encodes a 83.9 kD protein having 739 amino acids and prolyl oligopeptidase activity.
With reference to Table 1, the amino acid sequence of Coprinus clastophyllus prolyl oligopeptidase was aligned with amino acid sequences of prolyl oligopeptidases from other species using the GAP utility of GCG software (Accelrys). A highest identity (45.8%) to Xenopus tropicalis and a secondary highest identity (44.7%) to ustilago maydis were observed. Though Coprinus clastophyllus and Cryptococcus neoformans belong to the same genus, identities in a range between 40%-43.9% for human, mouse, pig, blue-green algae, Arabidopsis thaliana or bovine were higher than the identities in a range between 31.6%-32% to Cryptococcus neoformans .
TABLE 1
Similarities and identities of prolyl oligopeptidase amino acid
sequences between Coprinus clastophyllus and other species
Species
Similarity (%)
Identity (%)
Xenopus tropicalis
54.6
45.8
Ustilago maydis
54.2
44.6
Anabaena variabilis
55.1
43.9
Human
54.6
43.8
Human-2
54.5
43.7
Mouse
53.7
43.5
Rat
53.5
43.5
Pig
54.0
43.2
Nostoc sp.
54.9
43.2
Oryza sativa
53.2
43.2
Arabidopsis thaliana
52.6
43.2
Bovine
53.2
43.0
Deinococcus radiodurans
49.6
39.9
Aeromonas punctata
50.8
39.2
Aeromonas hydrophila
49.9
38.6
Novosphingobium capsulatum
47.2
37.7
Flavobacterium meningosepticum
47.4
37.6
Pyrococcus horikoshii
45.2
34.9
Pyrococcus abyssi
46.6
34.6
Pyrococcus furiosus
44.9
33.2
Cryptococcus neoformans
44.5
32.0
Cryptococcus neoformans -2
42.2
31.6
Pseudomonas entomophila
36.0
28.5
Neisseria menigitidis
34.9
27.1
It is observed that various proteins of amino acid sequences having similarity lower than 60% to the amino acid sequence of SEQ ID NO:6 encoded by nucleic acid SEQ ID NO:5. Variations of amino acid sequences do not necessarily alter the prolyl oligopeptidase activities. Thus it will be understood by a person skilled in the art that proteins having the aforementioned prolyloligopeptidase activities as in the present invention may also have similarities greater than 60% therewith. These varying proteins are also covered within the scope of the present invention.
Example 2
Expression of Coprinus clastophyllus Prolyl Oligopeptidase cDNA in E. coli
Primers Pro31 and Pro32 were designed to generate a stop codon in an amplified full-length prolyl oligopeptidase cDNA using PCR with pfu DNA polymerase.
Pro 31:
5′-atggtgacca aaacctgggt-3′
(SEQ ID NO: 7)
Pro 32:
5′-ctagagtgta gctttatctt tc-3′
(SEQ ID NO: 8)
PCR program:
94° C., 3 minutes [1 repeat];
94° C., 30 seconds, 58° C., 30 seconds, 72° C., 180 seconds [35 repeats];
72° C., 3 minutes [1 repeat].
The amplified full-length prolyl oligopeptidase cDNA was ligated into an expression vector pET 151/D-TOPO (Invitrogen) comprising a T7 primer corresponding sequence and an N-terminal His-tag. A recombinant construct was obtained as a result of the ligation. The recombinant construct was then used to transform host cells. The host cells were DH10B E. coli strain cells (Invitrogen). The host cells were cultured at 37° C. in LB broth (USB) or on LB plates (USB). Multiple colonies were obtained and 3 colonies were further selected. Recombinant plasmids were obtained from the cells of the selected colonies. The recombinant plasmids were further used to transform host cells, being BL21(DE3) E. coli strain cells (Invitrogen), for expression.
The BL21(DE3) host cells were divided into 3 groups each group was respectively transformed with the recombinant plasmids obtained from the 3 colonies which were further selected. The BL21(DE3) host cells were added to shaking flasks containing LB broth and the densities of OD 600 readings were within 0.4-0.6. 0.4 mM (final concentration) of IPTG was added into each flask and the cultivation lasted for another 20 hours thereafter. Coprinus clastophyllus prolyl oligopeptidase cDNAs carried by the recombinant plasmids were expressed in the BL21(DE3) host cells. The expressed proteins having prolyl oligopeptidase activities were purified according the purification methods disclosed in the manual of the pET system (Novagen). Bio-Rad Protein Assay (Bio Rad) was used to measure masses of the expressed proteins. Standard curves were plotted using BSA (bovine serum albumin) as standard to determine masses of the expressed proteins.
Example 3
Measuring Activity of Coprinus clastophyllus Prolyl Oligopeptidase
1. Selecting pProHN14 and pProHN17 and Measuring Prolyl Oligopeptidase Activities of Proteins Encoded Thereby
400 μl of 0.1 M Na-phosphate buffer, 50 μl of 10 mM Z-glycyl-L-proline-4-nitroanilide (Fluka) and 50 μl of diluted solution of the aforementioned protein having prolyl oligopeptidase activity were added into a micro centrifuge tube. The mixture was allowed to react for 5 to 60 minutes. 500 μl of 1N HCL quenching solution was added to quench the reaction. After 13000 rpm centrifugation for 5 minutes, the supernatant was obtained to measure the reading of OD 410 .
The amount of p-nitroaniline was determined with a stand curve of OD 410 readings versus p-nitroaniline amounts. At pH 7.0 and 45° C., 1 U of prolyl oligopeptidase activity was defined as the ability to generate 1 μmole of p-nitroaniline per minute.
The reading of OD 410 was than used to determine the prolyl oligopeptidase activities shown in the aforementioned 3 groups of BL21(DE3) host cells. The 2 groups having highest prolyl oligopeptidase activities were selected. The recombinant plasmids carried in the 2 groups of BL21(DE3) host cells were pProHN14 and pProHN17. The proteins respectively encoded by pProHN14 and pProHN17 showed prolyl oligopeptidase activities of 7.2 U/ml and 7.7 U/ml.
2. Sequencing pProHN14 and pProHN17
The recombinant plasmids, pProHN14 and pProHN17, were sequenced with available sequencing techniques to those skilled in the art. The sequence of pProHN17 was shown in the nucleic acid sequence of SEQ ID NO:5 as predicted.
In addition, the nucleic acid sequence of pProHN14 was shown in SEQ ID NO: 9. It was observed by comparing SEQ ID NO:5 and SEQ ID NO:9 that 4 nucleotides (CTAG) were deleted in the C-terminal of pProHN14 and frame-shift were induced. As a result, 24 amino acids (R ASSDPAANKA RKEAELAAAT AEQ) (SEQ ID NO: 11) were added to the C-terminal of the protein expressed from pProHN14. The amino acid sequence of the protein expressed from pProHN14 was shown in SEQ ID NO:10.
In an aspect of the present invention, a DNA fragment having the sequence of pProHN14 (SEQ ID NO:9), is obtained from BCRC 36074 as a PCR template, using a PCR primer having the aforementioned 4 nucleotides (CTAG) deleted. The DNA fragment has the nucleic acid sequence of SEQ ID NO:9. By expressing the DNA fragment with an expression vector, a protein having amino acid sequence of SEQ ID NO:10 is obtained. In a preferred aspect of the present invention, pET151/D-TOPO is used as the expression vector.
3. Comparison of Activities and Specific Activities of Known Prolyl Oligopeptidase and that of Proteins Encoded by pProHN14 and pProHN17
The proteins expressed from pProHN14 and pProHN17 in host cells of BL21(DE3) E. coli strain exhibit prolyl oligopeptidase activities of 7.2 U/ml and 7.7 U/ml, which is similar to the activity (8.1 U/ml) of Flavobacterium meningosepticum prolyl oligopeptidase and is superior to most known prolyl oligopeptidase.
Ni-NTA affinity column packed with Ni-NTA gel was commercially available in Invitrogen. The Ni-NTA affinity column was used to purify proteins expressed from pProHN14 and pProHN17. Purified proteins of pProHN14 and pProHN17 were observed to have specific activities of 56.1 U/mg and 66.8 U/mg, which were lower than the specific activity of Flavobacterium meningosepticum prolyl oligopeptidase but higher than most known prolyl oligopeptidase.
Example 4
Analysis Basic Properties of Proteins Encoded by pProHN14 and pProHN17
1. Optimum pH for Coprinus clastophyllus Prolyl Oligopeptidases
The aforementioned method for determining prolyl oligopeptidase activity was used to determine an optimum pH value using pH 3-8 citric acid-Na 2 HPO 4 buffer solution or pH 9-12 glycine-NaOH buffer solution.
The proteins expressed from pProHN14 and pProHN17 demonstrated highest prolyl oligopeptidase activity at pH 7.0. With reference to FIG. 1 , the protein of pProHN14 demonstrated a wider range of optimum pH. The protein of pProHN14 exhibited 90% activity while the protein of pProHN17 exhibited only 50% at pH 6.0.
2. Optimum Temperature for Coprinus clastophyllus Prolyl Oligopeptidases
Optimum temperature was determined by measuring prolyl oligopeptidase activities at 25° C., 30° C., 37° C., 45° C. or 45° C. with the aforementioned method for determining prolyl oligopeptidase activity.
With reference to FIG. 2 , at pH 7.0, the proteins of pProHN14 and pProHN17 exhibited highest activity at 45° C. Thus the optimum temperature was determined to be 45° C., which is higher than the optimum temperatures of prolyl oligopeptidases known to show high activities.
With reference to FIG. 3 , at pH 8.0, the proteins of pProHN14 and pProHN17 exhibited highest activity at 37° C.
3. Heat Stability Coprinus clastophyllus Prolyl Oligopeptidases
The proteins of pProHN14 and pProHN17 were preheated at 30° C., 37° C. or 45° C. for 0, 20, 40, 60 or 80 minutes or preheated at 55° C. for 0, 5, 10 15, 20, 25 or 30 minutes. The activities of preheated proteins were then measured with the aforementioned method for determining prolyl oligopeptidase activity.
With reference to FIG. 4 , being preheated at 30° C. or 37° C. for 80 minutes, the protein expressed from pProHN14 was observed to retain 99% and 93% of activities. The protein expressed from pProHN17 was observed to retain 80% and 73% of activities under the same conditions.
Being preheated at 45° C. for 60 minutes, the protein of pProHN14 was observed to retain 67% of activity. The protein of pProHN17 was observed to retain 32% of activity. Thus it was apparent that the protein of pProHN14 has better heat stability than the protein of pProHN17.
Being preheated at 55° C. for 5 minutes, the proteins of pProHN14 and pProHN17 were both observed to retain only 9% activities.
Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and features of the invention, the disclosure is illustrative only. Changes may be made in the details, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
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Proteins isolated from Coprinus clastophyllus having prolyl oligopeptidase activity, nucleic acids encoding the protein and methods for producing and using the protein, wherein SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:9 and SEQ ID NO:10 must be contained therein to at least 60% similarity. The proteins and nucleic acids have improved heat stability and perform more favorably in vivo having optimum activity conditions around 40 degrees centigrade and around pH 7, and can therefore be used in medicaments for the treatment of celiac disease caused by proline abundant gluten or other applications.
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FIELD OF THE INVENTION
The present invention relates to a method and apparatus suitable for resolving algebraic loops in execution of a model, and more particularly to a method and software application for identifying and resolving artificial algebraic loops in model executions.
BACKGROUND OF THE INVENTION
Dynamic systems are typically modeled in simulation environments as sets of differential, difference, and/or algebraic equations. At any given instant of time, these equations may be viewed as relationships between the system's output response (“outputs”), the system's input stimuli (“inputs”) at that time, the current state of the system, the system parameters, and time. The state of the system may be thought of as a numerical representation of the dynamically changing configuration of the system. For instance, in a physical system modeling a simple pendulum, the state may be viewed as the current position and velocity of the pendulum. Similarly, a signal-processing system that filters a signal would maintain a set of previous inputs as the state. The system parameters are the numerical representation of the static (unchanging) configuration of the system and may be viewed as constant coefficients in the system's equations. For the pendulum example, a parameter is the length of pendulum and for the filter example; a parameter is the values of the filter taps.
There are four common types of mathematical models used in the study of dynamic systems. The first type of mathematical model describes systems using ordinary differential equations (ODEs) and is depicted in FIG. 1A . The dynamic system 2 specifies a set of two equations: Output 4 and Derivative 6 . The Output equation 4 facilitates the computation of the system's output response at a given time instant as a function of its inputs, states, parameters, and time. The Derivative equation 6 is an ordinary differential equation that allows the computation of the derivative of the states at the current time as a function of the inputs, the states, parameters, and time. This class of models is suitable for systems in which it is important to track the system response as a continuous function of time. Such continuous-time systems are commonly representative of physical systems (mechanical, thermal, electrical). For simple systems, it may be possible to use the Output 4 and Derivative equations 6 to obtain a closed-form solution for the output response y(t). But in most complex real world systems, the response of the system is obtained by integrating the states through numerical means.
The definition of an ODE used herein encompasses both implicit and explicit differential equations. The class of ordinary differential equations may require additional equations to define the system being modeled. For example, equations called projections may be required to impose constraints on the differential variables (e.g., states X 1 and X 2 must fall on the manifold defined by x 1 2 +x 2 2 =25). These constraints can be either applied as a secondary condition or a coupled condition to the differential equation. Although systems including the projections may conventionally no longer qualify as an ODE; they are included here to simplify the categories of systems. Another example is the use of a Jacobian equation that defines partial derivatives with respect to the independent and/or differential variables. The Jacobian equation is typically used when obtaining a linear approximation of a non-linear model or an overall linear model of a set of equations. Jacobian equations are required for some forms of numerical integration, for producing the linear model once the model has reached its steady state operating point, etc. The Output 4 and Derivatives equations 6 may be extended to define other relationships for the block. For example, the Output equation 4 may help manage its states by defining a relationship where it resets the state back to a known quantity at a specific point in time or when a specific condition is seen.
Another type of mathematical model describes systems using difference equations as depicted in FIG. 1B . The dynamic system 8 specifies a set of two equations: Output 10 and Update 12 . The Output equation 10 facilitates the computation of the system's output response at a given time instant as a function of the inputs, states at some previous time, parameters, and time. The Update equation 12 is a difference equation that allows the computation of the states at the current time as a function of the inputs, states at some previous time, parameters, and time. This class of models is suitable for systems in which it is important to track the system response at discrete points in time. Such discrete-time systems are commonly representative of discrete-time control and digital signal processing systems. For simple systems, it may be possible to use the Output 10 and Update equations 12 to obtain a closed-form solution for the output response y(t). But in most complex real world systems, the response of the system is solved through recursion. The Output 10 and Update equations 12 are applied repeatedly to solve for the system response over a period of time.
An additional type of mathematical model describes systems using algebraic equations as depicted in FIG. 1C . The dynamic system 14 uses an algebraic equation 16 that needs to be solved at each time to obtain the outputs. While simple systems may allow one to obtain a closed-form solution for the system inputs and outputs, practical algebraic equations may best be solved iteratively using a numerical method involving both perturbations and iterations. Algebraic equation solving techniques used in the context of dynamic system modeling are discussed in greater detail below.
A fourth type of mathematical model is a composite system that has components that fall into the three types of models discussed above. Most complex real-world system models fall into this category. This class of systems has Output, Derivative, Update, and potentially other equations. Solving for the output response of such systems requires a combination of the solution approaches discussed for all of the classes above. One example of a composite system is one described by differential-algebraic equations (DAEs) which contain both differential equations and algebraic equations. Grouped within the composite class of systems are many extensions involving relationships (equations) defined in terms of both outputs and state. For example, one can define a limited integration relationship for a differential variable. This relationship requires a set of equations that includes the Output equation, an Update equation, a Derivative equation, and a Zero-crossing equation. The Zero-crossing equation defines the points in time where the upper and lower limits of the limited integration occur. Another example of an extension is the notion of Enable and Disable equations that define relationships among states or signals when parts of a system are activated and deactivated during execution.
Inherent in the four classes of systems (ODE, difference equations, algebraic equations and composite) is the notion of system sample time. The sample time is the time interval at which the inputs, state, or outputs (collectively referred to as the results) of the system are traced as time progresses. Based on sample times, a system can be described as a discrete-time system, continuous-time system and hybrid system. A discrete-time system is a system in which the evolution of the system results are tracked at finite intervals of time. In the limit as the interval approaches zero, the discrete-time system becomes a continuous-time system. The intervals of time may be periodic or non-periodic. Sometimes, non-periodic rate systems are referred to as non-uniform rate systems meaning that there is no periodic rate at which the response can be tracked. Non-uniform-rate systems can fall into the class of composite systems where an additional equation (GetTimeOfNextVarHit) defines when in the future the other equations associated with the system should be evaluated. A continuous-time system is a system in which the evolutions of the system results are continuously changing. Continuous-time signals change during numerical integration (minor time steps). An example of a continuous-time system is one described by an ODE. There can also be algebraic or composite continuous-time systems. A hybrid system is a system with both discrete-time and continuous-time elements.
If a system has only one sample time, it is said to be single-rate. If a system has multiple sample times, it is said to be multi-rate. Multi-rate systems can be evaluated (executed) using either a single-tasking form of execution or a multi-tasking form of execution. When multi-tasking execution is used, it conforms to rate monotonic scheduling principals as defined by LIU, C. L., and LAYLAND, J. W. Scheduling Algorithms for Multiprogramming in a Hard - Real - Time Environment . ACM 20, 1 (January 1973), 46–61. Systems may also be categorized by the type of numerical integration solver being used. A fixed-step system is one that uses a fixed-step solver. Fixed-step solvers typically use explicit methods to compute the next continuous state at fixed periodic intervals of time. A variable-step system is one that is using a variable-step solver. A variable-step solver can use either implicit or explicit methods to compute the next continuous state at non-periodic intervals of time. Generally, variable-step solvers use a form of error control to adjust the interval size such that the desired error tolerances are achieved.
In practice, except for the most basic systems, mathematical models for dynamic systems involve a complex set of mathematical transformations applied in some prescribed manner with the outputs of some transformations forming the inputs of others. Each elemental transformation may be viewed in isolation as a simple dynamic system falling into one of the categories listed above. Therefore, a complex dynamic system may be modeled as an interconnection of various simple dynamic systems. A schematic representation of such an interconnection that has evolved over the years is the block diagram. Such block diagram models have now become a standard means in textbooks, design papers, journal articles, and specifications to communicate the details of a dynamic system's behavior.
A block diagram model of a dynamic system is represented schematically as a collection of blocks interconnected by lines that represent signals. A signal represents the input and output of a dynamic system. Each block represents an elemental dynamic system. A line emanating at one block and terminating at another signifies that the output of the first block is an input to the second block. Each distinct input or output on a block is referred to as a port. Signals correspond to the time-varying quantities represented by each line connection and are assumed to have values at each time instant. The source block of a signal writes to the signal at a given time instant when its system equations are solved. The destination blocks of this signal read from the signal when their system equations are being solved. The basic components of a block diagram are illustrated in FIG. 2 . The block diagram includes a plurality of blocks 20 , lines 22 and ports 24 that are interconnected. Those skilled in the art will recognize that the term “blocks” does not refer exclusively to elemental dynamic systems but may also include other modeling elements that aid in readability and modularity of block diagrams.
The theory of Digital Signal Processing (DSP) focuses on modeling signals as sequences of samples. This view naturally fits into the time-based block diagram paradigm by mapping the samples u[n] to discrete-time points u(t k ). This adds the benefit of being able to model the interaction between DSP systems and other classes of time-based systems, e.g. continuous and/or discrete-time control systems.
Put another way, block diagram models are time-based relationships between signals and state variables representative of a dynamic system. The solution (computation of system response) of the model is obtained by evaluating these relationships over time, where time starts at a user-specified “start time” and ends at a user-specified “stop time”. Each evaluation of these relationships is referred to as a time step. Signals represent quantities that change over time, and these quantities are defined for all points in time between the block diagram's start and stop time. The relationships between signals and state variables are defined by sets of equations represented by blocks. These equations define a relationship between the input signals, output signals, state, and time. Inherent in the definition is the notion of parameters, which are the coefficients of the equations.
It is important to note that block diagrams are not exclusively used for representing time-based dynamic systems but also for other models of computation. For instance, flow-charts are block diagrams used to capture process flow and are not generally suitable for describing dynamic system behavior. Data flow block diagrams are block diagrams that describe a graphical programming paradigm where the availability of data (often thought of as tokens) is used to initiate the execution of blocks, where a block represents an operation and a line represents execution dependency describing the direction of data flowing between blocks. As used herein, the term block diagrams means time-based block diagrams used in the context of dynamic systems except as otherwise noted.
Block diagram modeling has spawned a variety of software products such as Simulink® from the MathWorks, Inc. of Natick, Mass., that cater to various aspects of dynamic system analysis and design. Such products allow users to perform various types of tasks including constructing system models through a user-interface that allows drafting block diagram models, allowing augmentation of a pre-defined set of blocks with custom user-specified blocks, the use of the block diagram model to compute and trace the temporal evolution of the dynamic system's outputs (“executing” the block diagram), and automatically producing either deployable software systems or descriptions of hardware systems that mimic the behavior of either the entire model or portions of it (referred to herein as “code generation”). Each of the tasks listed above has many intricate details and subtle variations that are explored further below.
Block modeling software includes a number of generic components. Although the discussion contained herein focuses on Simulink® version 5.0 (Release 13) from the MathWorks, Inc. of, Natick Mass., those skilled in the art will recognize that it is applicable to other block modeling software applications. The generic components include a block diagram editor, blocks and a block diagram execution engine. The block diagram editor allows users to perform such actions as draw, edit, annotate, save, and print out block diagram representations of dynamic systems. As noted earlier, blocks are the fundamental mathematical elements of a classic block diagram model. Simulink® extends the classic block diagram models by introducing the notion of two classes of blocks, nonvirtual blocks and virtual blocks. Nonvirtual blocks are elementary dynamic systems. A virtual block is provided for graphical organizational convenience and plays no role in the definition of the system of equations described by the block diagram model. Examples of virtual blocks are the Bus Creator virtual block and Bus Selector virtual block which are used to reduce block diagram clutter by managing groups of signals as a “bundle”. Virtual blocks may be used to improve the readability of models. Simulink® further extends the meaning of a nonvirtual block to include other semantics, such as a “merge” block semantic. The merge block semantic is such that on a given time step its output is equal to the last block to write to an input of the merge block. An additional extension provided by Simulink® is the concept of conditional execution. Simulink® contains the concept of conditional and iterative sub-systems that control when in time block methods execute for a sub-section of the overall block diagram.
A block diagram execution engine contributes to the modeling software task of enabling the computation and tracing of a dynamic system's outputs from its block diagram model. An execution engine carries out the task of compiling and linking the block diagram to produce an “in-memory executable” version of the model that is used for generating code and/or simulating or linearizing a block diagram model. Note that execution of the block-diagram is also referred to as simulation. The compile stage involves checking the integrity and validity of the block interconnections in the block diagram. In this stage, the engine also sorts the blocks in the block diagram into hierarchical lists that are used when creating the block method execution lists. In the link stage, the execution engine uses the result of the compiled stage to allocate memory needed for the execution of the various components of the block diagram. The linking stage also produces block method execution lists that are used by the simulation or linearization of the block diagram. Included within the link stage is the initialization of the model which includes the evaluating of “setup” methods (e.g. block start, initialize, enable, and constant output methods). The block method execution lists are generated because the simulation and/or linearization of a model must execute block methods by type (not by block) when they have a sample hit.
After linking has been performed, the execution engine may generate code. In this stage, the execution engine may choose to translate the block diagram model (or portions of it) into either software modules or hardware descriptions (broadly termed code). If this stage is performed, then the stages that follow use the generated code during the execution of the block diagram. If this stage is skipped completely, then the execution engine uses an interpretive mode of execution for the block diagram. In some cases, the user may not proceed further with the execution of the block diagram because they would like to deploy the code outside the confines of the block diagram software. Upon reaching the simulation stage, the execution engine uses a simulation loop to execute block methods in a pre-defined ordering upon a sample hit to produce the system responses as they change with time.
For linearization, Simulink® uses the block method execution lists in a prescribed fashion to produce a linear state space representation of the dynamic system described by the block diagram.
The block diagram editor is the graphical user interface (GUI) component that allows drafting of block diagram models by a user. In Simulink®, there is also a textual interface with a set of commands that allow interaction with the graphical editor. Using this textual interface, users may write special scripts that perform automatic editing operations on the block diagram. A user generally interacts with a set of windows that act as canvases for the model. There is generally more than one window for a model because models may be partitioned into multiple hierarchical levels through the use of sub-systems (discussed further below).
A suite of GUI tools in Simulink® allows users to draft a block diagram model on the corresponding windows. The GUI tools include a block palette, wiring line connection tool, annotation tool, formatting tool, attribute editing tool, save/load tool and publishing tool. The block palette is a library of all the pre-defined blocks available to the user when they are building the block diagram. Individual users may be able to customize this palette to: (a) reorganize blocks in some custom format, (b) delete blocks they do not use, and (c) add custom blocks they have designed. The palette allows blocks to be dragged through some human-machine interface (such as a mouse or keyboard) from the palette on to the window (i.e., model canvas). The graphical version of the block that is rendered on the canvas is called the icon for the block. There may be different embodiments for the block palette including a tree-based browser view of all of the blocks.
The wiring line connection tool allows users to draw directed lines that connect the ports of blocks in the model's window. Lines are also added through various mechanisms involving human-machine interfaces such as the mouse or keyboard. Simulink® also provides various forms of auto-connection tools that connect blocks automatically on user request to produce an aesthetically pleasing layout of the block diagram (especially those with high complexity with large numbers of blocks). The annotation tool allows users to add notes and annotations to various parts of the palette for a block diagram. The formatting tool enables users to perform various formatting operations that are generally available on any document editing tool. These operations help pick and modify the various graphical attributes of the block diagram (and constituent blocks) such as include font-selection, alignment & justification, color selection, etc. The block diagram and all the blocks within the block diagram generally have a set of functional attributes that are relevant for the execution or code-generation. The attribute editing tool provides GUIs that allows these attributes to be specified and edited. The save/load tool allows a created block diagram model to be saved. The saved model can be reopened in the editor at some later juncture through a load mechanism. Simulink® also allows users to save blocks including pre-constructed sub-systems into a separate class of block-diagrams called libraries. Such libraries facilitate reuse of the same block in a number of other block diagrams. The load/save mechanism is specially equipped to handle loading and saving of blocks in a block-diagram that actually reside in libraries.
The publishing tool enables the viewing of the block diagram as a document that can be published in any of the standard document formats (examples: PostScript, PDF, HTML, etc.). Those skilled in the art will recognize that the windows for multiple models and all of the tools mentioned above could potentially be embedded in a single Multi-Document Interface (MDI) for providing a unified software environment.
Those skilled in the art will also recognize that block-diagram packages offer scripting languages for writing out programs that automatically carry out a series of operations that would normally require interaction with the GUI. For example, Simulink® offers a set of commands in MATLAB for carrying out operations such as block addition (add_block), block deletion (delete_block), starting and terminating execution (set_param), modifying block attributes (set_param/get_param), etc.
Simulink® also offers a variety of other GUI tools that improve the ability of users to build and manage large block diagrams. Examples of such GUIs include: (a) a Finder that helps find various objects such as blocks and lines within a block-diagram, (b) a Debugger that helps debug the execution of block-diagrams, (c) a Revision Control UI for managing multiple revisions of the block-diagram, and (d) a Profiler for viewing timing results while executing a block-diagram.
A typical base data-structure for a block may be represented as:
class Block { public: // Access methods for setting/getting block data . . . // Methods for block editing virtual ErrorStatus BlockDrawIcon( ); virtual BlockParameterData BlockGetParameterData( ); . . . // Methods for block compilation . . . // Methods for block execution ............................................. virtual ErrorStatus BlockOutput( ) = 0; virtual ErrorStatus BlockDerivative( ) = 0; virtual ErrorStatus BlockUpdate( ) = 0; . . . private: BlockGraphicalData blkGraphicalAttributes; BlockFunctionalData blkFunctionalAttributes; BlockCompiledData blkCompiledAttributes; BlockExecutionData blkExecutionData; . . . };
Although the example of the data structure above is written in C++, those skilled in the art will recognize that equivalent data structures written in other languages may also be used. The major data fields of the block data structure fall into four categories, a graphical attributes field, a functional attributes field, a compiled attributes field and an execution data field.
The graphical attributes field is responsible for storing information relevant for graphical rendering of the block within its parent block diagram's GUI. Attributes specific to the block icon such as font, color, name, and icon-image are stored in this field. It should be noted that modifying these attributes does not affect the dynamics of the model using this block. The functional attributes field is responsible for specifying block attributes that may potentially affect the dynamics of the model using this block. These attributes are specified for the block as a whole and the input and output ports of the block. Examples of block attributes include block sample times and restrictive flags. Block sample times specify if the block corresponds to an elemental, continuous, discrete, or hybrid dynamic system. If the block is an elemental discrete-time system, then the attribute specifies the spacing between time instants at which the block response should be traced. A restrictive flag disallows the use of blocks in certain modeling contexts. For example, one may impose the restriction that there may only be one instance of given block in a model.
Attributes of block ports specify properties of the data that is either available or produced at that port. Block port attributes include dimensions, datatypes, sample rates, and direct feedthrough. Dimension attributes are individual dimensions of a multi-dimensional matrix that is used as a container for data elements. Datatype attributes are the datatype of each element of data in the data container. A complexity attribute is a flag to specify if each data element is real or complex. A sample rate attribute specifies how when the signal corresponding to an input or output port will be used. The port sample times may sometimes be used to implicitly infer the block's sample time. The direct feedthrough attribute is specified only for input ports and indicates whether or not the Output and/or GetTimeOfNextHit equations of the block are a function of the given input. This attribute helps in determining the sequence in which block methods should be executed while executing the block diagram.
The compiled attributes field of the block data structure holds the attributes of the block and its ports that mirror the functional attributes listed above. This field is filled in during block diagram compilation by utilizing the functional attributes of the block in conjunction with the functional and compiled attributes of the blocks that are connected to it. This process of determining the compiled attributes from the functional attributes is termed attribute propagation. Attribute propagation is described in greater detail below in the section on block diagram compilation. The execution data field is mainly responsible for storing the memory locations that are going to serve as sources for block inputs, outputs, states, parameters, and other work areas during execution of blocks.
The block data structure also has a set of associated methods that may be categorized as access methods to data fields, methods used in editing, methods used in compilation and methods used in execution. Access methods to data fields help in setting and getting the various data fields of the block. Methods used in editing are called by the block diagram editor in order to render the block appropriately in the GUI of its parent block diagram. For instance, this set of methods may include a BlockDrawIcon method that determines the shape the block icon has on the GUI. Methods used in compilation are methods that are called by the block diagram compilation engine. They help validate the connections of the block to other blocks on the block diagram. The methods used in execution include a number of different run-time methods that are required for execution. These include the BlockOutput, BlockUpdate, BlockDerivative methods that realize the Output, Update, and Derivative equations discussed earlier in the context of dynamic systems. In addition to these methods, Simulink® includes several other run-time methods, such as the Jacobian, Projection, ZeroCrossings, Enable, Disable, Initialize, EvalParams (check and process parameters), and GetTimeOfNextHit methods. It should be noted that there is no explicit method for algebraic equations because these are represented and processed in a different manner which will be discussed below.
The base data structure for the block specifies the generic fields and interfaces that need to be supported by a block. Some of the methods are purely virtual and have no specific implementation in the base block class. In order to define a specific block (such as an Integrator block), one needs to subclass the base block class and provide explicit definitions for these virtual methods. An example of the subclassing of a block may be seen by examining an Integrator block. FIG. 3 depicts the desired behavior of an Integrator block 30 . In order to create the subclass, four major categories of information within the subclass must be specified, the block parameters, the methods used in editing, the methods used in compilation, and the methods used in execution. The elemental dynamic system embodied by the block may be parameterized as illustrated in FIGS. 1A–1C . Each block needs to be able to specify its list of expected parameters. The block diagram editor's Attribute-Editing tool may allow users to specify the parameters for the block when they use it in their models. In the Integrator block example, the block has one parameter that specifies the block's initial condition for the block's state. Regarding the methods used in editing, the subclass needs to specify a method that renders its icon. For example, the Integrator block may implement a method that makes its icon be a box with a ‘1/s’ within the box. Also, the subclass needs to instantiate a method that allows access of the block parameters from the GUI's Attribute-Editing tool. For the Integrator example, this method would allow users to specify the Initial Condition parameter on a GUI for the block. For the methods used in compilation, the subclass needs to instantiate methods that help in the compilation of the block diagram model in which it is placed. These methods help specify the compiled information for the inputs and outputs of the block. For instance, the Integrator block may specify a method that ensures that if the input to the Integrator is a vector, then the output is a vector of the same size. For methods used in execution, the subclass needs to instantiate specific Output, Derivative, and Update methods that represent the block behavior. In the case of the Integrator block, an Output and Derivative method are needed. It should be noted that in Simulink® the Integrator block has additional methods that are not illustrated here. The Output method sets the output to be equal to the state. The Derivative method sets the derivative of the state to be equal to the input.
The specification of these four types of information for the Integrator block subclass may be shown by a reduced form of the Simulink® Integrator block:
IntegratorBlock : public Block { public: ErrorStatus BlockDrawIcon( ) { // Draw ‘1/s’ on the icon .............................. } BlockParameterData BlockGetParameterData( ) { // Return initial_condition as block data .............................. } ErrorStatus BlockOutput( ){ // Implement y(t) = x(t) .............................. } ErrorStatus BlockDerivative( ){ // Implement dx(t)/dt = u(t) .............................. } private: double initial_condition; };
It should be noted that block diagram software generally provides open access to the block's data structure to users of the software. This allows users to create and utilize custom block implementations in their models.
Blocks in a block diagram may be virtual or nonvirtual. The designation of a block as nonvirtual indicates that it influences the equations in the mathematical model for the dynamic system. In the context of block diagram software, it is beneficial to include other virtual blocks that do not affect the equations in the dynamic system's model. Such blocks help improve the readability and modularity of the block diagram and wield no semantic influence on the mathematical model. Examples of such virtual blocks include virtual sub-systems, inport blocks and outport blocks, bus creator blocks and From and Goto blocks.
Modularity may be achieved in a block diagram by layering the block diagram through the use of sub-systems. A sub-system facilitates layering by allowing a collection of blocks to be represented by a single block with input and output signals. The input and output signals of the sub-system are accessible to the constituent blocks within the sub-system. A sub-system is a virtual sub-system if its constituent blocks are moved back into the main block diagram model during the model's execution. Within a virtual sub-system graphical entities, called inport and outport blocks, are provided to define signal connections to the parent block diagram. These inport and outport blocks indicate a tunnel-through signal connection to the parent block diagram.
Additional types of virtual blocks include bus creator blocks and selector blocks. In large models, there may be an extensive set of lines that connect one section of a block diagram to another section. To avoid excessive clutter of lines and improve readability, there is typically a special block called a Bus Creator that helps bundle all of the lines together to form a single bus line. This single bus line then connects the two sections of the model. At the destination end of the line, a block called a Bus Selector helps un-bundle the individual lines so that they can be connected to other blocks.
Other virtual blocks include From blocks and Goto blocks that are special blocks that help avoid graphical clutter, e.g. a line that connects two distant sections of a block diagram. The line is terminated close to its originating point by a From block. At the other end, a new line is drawn from a From block that is hot-linked to the Goto block. Each Goto and From block has an associated tag that describes which blocks are connected together. An important point to be noted is that virtual blocks have neither execution data nor execution methods in their data structure.
Simulink® also provides the user with the ability to extend the simulator by providing the ability to enhance the simulator with blocks that define dynamic systems or are virtual properties. The extension is provided through a language independent API (e.g. C, C++, Ada, Fortran, Assembly, M).
As noted previously, to facilitate modeling fairly large and complex dynamic systems, Simulink® allows users to layer their block diagrams. A sub-system facilitates such layering by allowing a collection of blocks to be represented by a single block with input and output signals. The input and output signals of the sub-system are accessible to its constituent blocks. By nesting sub-systems within each other, one can create block diagrams with arbitrary layers of hierarchy. Ideally a sub-system has no impact on the meaning of the block diagram. Additionally, sub-systems provide a way of grouping blocks together and allowing other block diagram constructs to impose unified control on the constituent blocks. To enhance the modularity of sub-systems, modeling software also allows aggregated list(s) of parameters of the blocks within the sub-system to be accessed from a single GUI, and defines and displays special icons on the sub-systems. The process of defining the parameter list and the special icon is called masking a sub-system.
There are two main types of sub-system blocks, virtual sub-systems and nonvirtual sub-systems. Virtual sub-systems serve the purpose of providing the block diagram with a graphical hierarchy. Nonvirtual sub-systems behave like an elemental dynamic system with its own execution methods (Output, Update, Derivatives, etc.). These execution methods in turn call the execution methods of the constituent blocks.
The classes of nonvirtual sub-systems are:
Atomic sub-systems. These are similar to virtual sub-systems, with the advantage of grouping functional aspects of models at a given layer. This is useful in modular design.
Conditionally-executed sub-systems. These are nonvirtual sub-systems that execute only when a precondition is fulfilled:
Enabled sub-systems. These are similar to Atomic sub-systems, except that the constituent blocks only execute when an enable signal feeding the sub-system is greater than zero.
Triggered sub-systems. These are similar to Atomic sub-systems, except that the constituent blocks only execute when a rising and/or falling signal is seen on a triggering signal feeding the sub-system.
Enable with Trigger sub-systems. These are an intersection of the properties of Enabled and Triggered sub-systems.
Action sub-systems. These sub-systems are connected to action-initiator (e.g., an “If” or “SwitchCase” block), a block that explicitly commands the sub-system contents to execute. These sub-systems are similar to Enabled sub-systems except that the management of the “enabling” signal has been delegated to an action-initiator. Action sub-systems define a new type of signal, called an action signal that signifies which sub-systems are commanded to execute by the action-initiator.
Function-call sub-systems. These sub-systems provide a means of collecting blocks into a sub-system that is only executed when called by an owner block. The owner block may compute input signals for the sub-system before calling the sub-system. Additionally, the owner may also read output signals from the sub-system after calling it. Function-call sub-systems define a new type of execution control signal, called a function-call signal that contains no data. It is used to define the execution relationship between the owner block and the function-call sub-system. Function-call owners may also designate themselves as an “interrupt” source. In simulation, they simulate the effects of an interrupt and in code generation they can attach themselves to an (asynchronous) interrupt.
While sub-systems and For sub-systems.
These sub-systems execute the constituent blocks multiple times on a given time step.
Simulink® allows for several forms of block parameters to be defined. There are two general categories of parameters: those parameters that can be modified during simulation and those that cannot be modified. An example of a parameter that may be modified during simulation is the amplitude of a Sine Wave block if configured by the user to allow modification during execution. A parameter such as the amplitude specifies coefficients of the dynamic equation, in this case the amplitude of the sine wave function defined by the Sine Wave block. An example of a parameter that can never be modified during simulation is the sample time of the Sine Wave block. The parameters that can be modified during simulation are further broken down into other categories which include mapping the dialog parameter (e.g. the amplitude) to run-time parameters or converting the dialog parameter to an inlined (non-modifiable) parameter. Run-time parameters can further be mapped to mathematical expressions of tunable Matlab variables or Matlab parameter objects describing properties of the variables (called Simulink®.Parameter's). A global run-time parameter data structure is used within Simulink® to manage the block parameters during the execution of the model.
In addition to block parameters, there are model-wide parameters that are generally associated with the solver. These parameters include aspects such as the time span in which to perform a simulation, the type of solver, and the time span. Simulink® gives the user the ability to adjust solver parameters during model execution. The adjustment of these solver parameters is performed at the start of a time step.
Once a block diagram model has been constructed using the editor, an execution engine allows the model to be solved in order to trace the system outputs as a function of time. The solution of the model, which may be referred to as model execution, is carried out over a user-specified time span for a set of user-specified inputs. Simulation proceeds in four major stages: compilation, link, code generation, and the simulation loop. Alternatively, the execution engine can obtain a linear representation of the model (linearization). The interrelationship between the various stages is illustrated in a flowchart in FIG. 4 .
The execution begins when the block diagram 40 is compiled 42 . Following the compilation stage, is the model link stage 44 which may also produce linear models 46 . Code may or may not be generated 45 . If code is generated 48 , a decision is made 49 whether to continue the simulation. If the decision is made to continue the simulation the model is simulated/executed through the Simulation Loop 50 . If the simulation is not continued, the code may be delivered to a target 52 and executed in an external mode 54 . If code is not generated the block diagram may execute in interpretive mode when entering the Simulation Loop 50 .
The compile stage marks the start of model execution and involves preparing data structures and evaluating parameters, configuring and propagating block characteristics, determining block connectivity, and performing block reduction and block insertion. The preparation of data structures and the evaluation of parameters creates and initializes basic data-structures needed in the compile stage. For each of the blocks, a method forces the block to evaluate all of its parameters. This method is called for all blocks in the block diagram. If there are any unresolved parameters, execution errors are thrown at this point.
During the configuration and propagation of block and port/signal characteristics, the compiled attributes (such as dimensions, datatypes, complexity, or sample time) of each block (and/or ports) are setup on the basis of the corresponding functional attributes and the attributes of blocks (and/or ports) that are connected to the given block through lines. The attribute setup is performed through a process during which block functional attributes “ripple through” the block diagram from one block to the next following signal connectivity. This process (referred to herein as “propagation”), serves two purposes. In the case of a block that has explicitly specified its block (or its ports') functional attributes, propagation helps ensure that the attributes of this block are compatible with the attributes of the blocks connected to it. If not, an error is issued. For instance, if an Integrator block is implemented to only accept numbers of double precision datatype, then this block will error out if it is driven by a block that produces single precision data, unless the user has asked for an implicit data conversion. Secondly, in many cases blocks are implemented to be compatible with a wide range of attributes. Such blocks adapt their behavior in accordance with the attributes of the blocks connected to them. This is akin to the concept of polymorphism in object-oriented programming languages. For instance, a discrete-time Filter block could be implemented to accept any of the standard integer datatypes ranging from 8-bit to 128-bit. The exact implementation of the block is chosen on the basis of the specific block diagram in which this block finds itself. Included within this step are other aspects such as validating that all rate-transitions within the model yield deterministic results and that the appropriate rate transition blocks are being used.
The compilation step also determines actual block connectivity. Virtual blocks play no semantic role in the execution of a block diagram. In this step, the virtual blocks in the block diagram are optimized away (removed) and the remaining nonvirtual blocks are reconnected to each other appropriately. This compiled version of the block diagram with actual block connections is used from this point forward in the execution process Once actual block connectivity has been determined (by removing the virtual blocks) the block diagram may be further optimized by performing block reduction and insertion. During this step, nonvirtual blocks may be inserted or a set of nonvirtual blocks may be completely removed or reduced to a single equivalent block. Block insertion and reduction is mainly done to improve execution efficiency. Examples of block insertion and reduction include the removal of Gain blocks whose gain value is 1.
A Gain block is a block that multiplies its input value by a gain parameter, such as a simple amplifier. FIG. 5 depicts the replacement of a collection of blocks 60 , 62 , and 64 connected in a accumulator pattern and leading to result 66 with an equivalent synthesized block 68 representing the accumulator pattern leading to the same result 66 . A signal copy block may also be automatically inserted in order to make contiguous memory copies of signals that are made up of disjoint memory sections. Block insertion and reduction may also be performed at other suitable stages of compilation.
The way in which blocks are interconnected in the block diagram does not necessarily define the order in which the equations (methods) corresponding to the individual blocks will be solved (executed). The actual order is partially determined during the sorting step in compilation. Once the compilation step has completed, the sorted order cannot be changed for the entire duration of the block diagram's execution.
The first step in sorting involves transforming the graphical block diagram into a compiled (in-memory) directed graph consisting of arcs and vertices. The vertices are derived from some of the nonvirtual blocks. For instance, virtual and reduced blocks do not appear in the directed graph. The arcs represent data dependencies between the vertices. The data dependencies do not correspond to the signals in the block diagram. For example, all signals that connect to input ports without direct feed through are “cut” or ignored. In addition, data dependencies are added to capture implicit dependencies. For example, all inputs to a Function-Call sub-system are implicit data dependencies to the owner (caller) block.
The process of converting a block diagram into a compiled directed graph is shown in FIG. 6A . A block diagram 81 includes a Sine Wave 1 block 82 , a Sine Wave 2 block 84 , a Goto block 86 , a Function Call Generator block 88 , and a From block 90 . Also included are a Function Call Sub-system block 92 , a Sum block 94 , a Gain block 96 , an Integrator block 98 and an Outport (Output 1 ) block 100 . Those blocks that are not virtual or reduced appear on the corresponding directed graph 111 . The directed graph 111 includes a Sine Wave 1 vertice 112 , a Sine Wave 2 vertice 114 , a function-call generator vertice 116 , and a function call sub-system vertice 118 . Also included are a Sum vertice 120 , a Gain vertice 122 , an Integrator vertice 124 and an Outport 1 vertice 126 . The vertices are connected by arcs.
The graph is used to sort the blocks into a linear sorted list. FIG. 6B depicts a sorted list 128 generated from the compiled directed graph 111 which includes the elements appearing as vertices in the directed graph 111 sorted into order. The root block diagram has a sorted-list associated with it. Roughly speaking, each nonvirtual sub-system layer and some special block diagram elements also each have their own sorted-list. During the sorting of the graph into the list, strongly connected components are identified. The term strongly connected section, which is a term that originates from graph theory, is a subset, S, of the blocks of a block diagram such that any block in S is reachable from any other block in S by following signal connections and S is not a subset of any larger such set. Strongly connected sections are flagged as algebraic loops when all blocks have direct feedthrough (an example is shown in FIG. 6A consisting of the Sum 120 and Gain 122 blocks). Such loops correspond to a set of algebraic equations and are solved using iterations and perturbations during block diagram execution by solving for the algebraic variables. Algebraic variables are either specified by the user via Initial Condition blocks or chosen by the execution engine. Solving of algebraic loops is discussed further below.
Sorting must also take into consideration other user specified dependencies between the blocks. These dependencies include the concepts of priorities and placement groups. A block priority specifies the order in which the equations associated with a block are evaluated with respect to other blocks. Placement groups are a way of causing each class of block methods for a specified set of blocks to be “placed together” in the block method execution lists. The terms “data dependency” or “data precedence” as used herein refers to the arcs of the compiled directed graph and not the signals found within a block diagram. Attempting to correlate data dependencies directly to the signals found within a block diagram is incorrect and leads to the conclusion that Simulink® does not satisfy data dependencies, i.e., the execution of the operations or block methods does not satisfy data dependencies if one interprets signal connectivity as specifying data dependencies.
After compilation, the link stage commences. During this stage physical memory allocations are made in order to prepare for execution. Buffers are allocated for block input and output data buffers, states, and work areas. Additionally, block method execution lists that are derived from the sorted list allow for execution of the block diagram. Each block method execution list is a list of block methods that are to be executed in a sequence when each method within the list has a sample hit. There is generally a set of block method execution lists associated with each layer of the block diagram that corresponds to a nonvirtual sub-system. Nonvirtual sub-systems are either defined by the user or automatically synthesized during compilation to either efficiently execute the model or simplify the implementation of the semantics defined by Simulink®. In multi-tasking mode, the lists within each layer may be further partitioned when block diagrams have blocks with different sample rates. These lists are explained in greater detail below.
Those skilled in the art will recognize that while the block method execution lists are derived from the sorted list, they do not necessarily correspond one-to-one with the sorted lists. First, each block method execution lists contains only blocks that have such a block method of the given type (class) defined by the list. Second, block methods corresponding to components like the function-call sub-system do not appear on the block method execution lists because they are executed by an “owner” block.
Although included in the discussion of the compilation stage, it is not required that the time-based diagram perform the block sorting step during compilation. The sorting step is performed to achieve efficient execution. Ignoring efficiency, there is no semantic reason to perform the sorting step. Any random ordering of the block methods will work. In fact, any ordering of all block method execution lists except the Output block method execution list will result in the same level of efficiency. Randomly re-ordering the Output block method execution list will yield correct answers. If the Output block method list is randomly ordered, then the Simulation engine, when executing the Output block method execution list, continues sequencing through the Output block method execution list at each point in time until there are no changes.
Similarly included within the linking stage for the sake of simplicity, is the memory initialization of the model. The memory initialization of the model includes invoking block start, initialize, constant initialize, enable, and constant output methods. These are examples of some of the block methods that are used during model setup (prior to execution) to initialize the “state” of the system so that execution or linearization can commence.
The compiled and linked version of the block diagram may be directly utilized to execute the model over the desired time-span. This interpretive mode of execution is suitable for getting fine-grained signal traceability. It should be noted that the traceability associated with interpretive execution comes at the price of increased overhead in the form of additional execution-related data-structures and messaging in the engine. An alternative to the interpretive execution mode is to utilize the generated-code created by Real-Time Workshop tool for Simulink® models. In this mode, the engine (upon the behest of the user) translates a selected portion of the block diagram (or the entire block diagram itself) into code. Such code could be in a number of possible forms. The code may be instructions in a high-level software language such as C, C++, Ada, etc., hardware descriptions of the block diagram portions in a language such as HDL, or custom code formats suitable for interpretation in some third-party software. Alternatively, the code may be instructions suitable for a hardware platform such as a microprocessor, microcontroller, or digital signal processor, etc., a platform independent assembly that can be re-targeted to other environments, or just-in-time code (instructions) that corresponds to sections of the block diagram for accelerated performance.
The execution of a portion of the block diagram represented in code may be performed in a number of different ways based on the specific code format. The portion of the block diagram may execute a compiled version of the code generated in a high-level language (accelerated or software-in-the-loop simulation), the execution may simulate code that corresponds to a hardware description on a hardware simulator, (co-simulation execution), the execution may involve calling out to third-party software to run code generated for such software (co-simulation execution), or the execution may call out directly to hardware that will run code that was generated and compiled for that hardware (processor-in-the-loop execution).
There are several different advantages to execution through code generation: Execution of generated code can be more efficient than interpretive execution because of fewer data-structures and lesser internal messaging in the engine, although the increased efficiency generally comes at the cost of decreased execution traceability. Simulation of hardware descriptions during execution can help identify and resolve bugs in the software stage of a design project. Such bugs prove much more expensive to track and fix once the system has been implemented in hardware. Additionally, block diagram modeling software can be integrated with other software environments that are suitable for modeling and simulating special classes of systems. Models can be tested directly in hardware thereby making prototyping of new systems fast and cost-effective. For instance, consider the design of a controller for an anti-lock braking system of a car. The dynamics of the braking system can be executed in the interpretive mode in the block diagram. The controller itself can be implemented on a hardware micro-controller to test the efficiency of the control laws implemented within. Note that for such target execution, it is normally necessary for the time span over which a model is executed by the software to match real-world time. In other words, the software must allow real-time execution of the block diagram model. Those skilled in the art will recognize that when users generate code, they may choose to not proceed further with the block diagram's execution. They may choose to take the code and deploy it outside of the confines of the modeling software environment. This is normally the last step in the design of dynamic systems in a block diagram software package.
There are several forms of target code execution known to those skilled in the art such as Rapid Prototyping, Embedded System Deployment, and Hardware-in-the-Loop which execute a model or portions of a model via the generated code on a Real-Time System target. One aspect of deploying (executing) the generated code on a target is the notion of “external mode.” External mode refers to a system where Simulink® acts as a monitor and debugger of the generated code running in real-time on a target. In External Mode, users can change parameters and view signals via standard Simulink® elements. Another important aspect of the code generation technology is that it is very extensible. Provided with the Simulink® product family is the Target Language Compiler (TLC). This technology enables the creation of “active scripts” that control how the generated code is produced for a block diagram. Using TLC, one can tailor the generated code to suit their specific needs.
The execution of the block diagram uses a Simulation Loop (SimLoop) for solving for the block diagram's outputs for a specified set of inputs over a specified span of time (“Time” in reference to the Simulation Loop means the time-line corresponding to the tracing of the dynamic system's outputs, not real-world time unless otherwise noted). The term “SimLoop” applies to real-time systems where each iteration is tied to a physical periodic clock or other timer source. During this process, the block methods (equations) corresponding to the individual blocks are executed by type following their sorted order when they have a sample hit. The term “block execution” is loosely used to mean executing all block methods associated with the given block for a given time step, generally starting with the output method. Strictly speaking, blocks do not execute; the engine executes (evaluates) the appropriate block methods at the appropriate time points.
SimLoop has two variants “single-tasking” and “multi-tasking” depending on sample times. In general, the sample time of a block is the interval of time between calls to the Output, Update, and/or Derivative methods for a given block. In computing this interval, repeated calls at the same time instant (not in real-world time but the time corresponding to the execution of the dynamic system) are counted as the same call. A block's sample rate may also be thought of as the interval between successive executions of the block methods. If there is no uniform or regular interval between calls, then the block is said have a continuous sample time. If a uniform time interval can be found, then the block is said to have a discrete sample time equal to that interval. Although blocks may be associated with more than one sample time in a sufficiently complex dynamic system the descriptions contained herein are confined to blocks with a single sample-time. Those skilled in the art will recognize that the descriptions may be extended to encompass blocks with multiple sample times.
FIG. 7A depicts an abstract example of a block diagram being executed. The diagram includes a plurality of blocks 140 , 142 , 144 , 146 , 148 and 150 . The block ports that have direct feedthrough are explicitly marked (using the symbol ‘df’) 152 . Additionally, an abstract view of the execution methods instantiated by each block is shown in FIG. 7B . The blocks contain a number of different methods 160 , 162 , 164 , 166 and 168 . Execution methods includes the three basic execution methods discussed earlier: Output, Update, Derivative, as well as several other methods that aid in advanced block functions such as initialization, linearization and zero-crossing detection.(which are discussed below). The data-dependencies between the compiled vertices created during sorting are used to generate the Sorted List 170 shown in FIG. 7C .
A block diagram consisting of blocks that all have the same sample time is said to correspond to a single-rate system. A block diagram consisting of blocks that have more than one sample time corresponds to a multi-rate system. FIG. 8 depicts a multi-rate system, adding sample-time information to the block diagram of FIG. 7A . The plurality of blocks 140 , 142 , 144 , 146 , 148 , and 150 each have an associated sample time. Since the sample times in the block diagram differ between blocks, the system is considered a multi-rate system. Block A 140 , block E 148 and block F 150 each have a sample time of 0.1 seconds. Block B 142 , block C 144 and block D 146 each have a sample time of 1.0 seconds.
The SimLoop is the heart of the execution engine. Each full pass through the loop is responsible for computing the outputs of the system at a particular time. At the end of each loop, the execution time corresponding to the next pass through the loop is computed. If this time exceeds the stop time specified by the user, the execution terminates. Within the loop, the sequence in which individual block equations are solved is determined by two pieces of information: the sample times of the blocks and the sorted order determined during the Compile stage. The amalgamation of these two pieces of information gives the execution lists for the block diagram. Those skilled in the art will recognize that the execution lists are created in the Link stage and are explained in the context of SimLoops for convenience. There are two distinct approaches for building execution lists and using them in the SimLoop. These approaches correspond to the Single-tasking and Multi-tasking SimLoops summarized in the discussion on FIG. 10 below.
Simulink® also has the ability to modify coefficients (parameters) of blocks that declare their parameters as tunable. An example of such a block is a Sine Wave block that implements the function: output (time)=amplitude*sin(frequency*time+phase) +bias, where time is the independent variable and the parameters are: amplitude, frequency, phase, bias. When these parameters are declared as tunable, Simulink® lets the user change these coefficients during simulation. Changing parameters is a drastic operation in that the definition of the model has changed (e.g. the sine block defines equations that describe the system). Thus, to enable the changing of parameters during the SimLoop®, Simulink® first queues parameter changes and then applies them on the next time step. Thus, the changing of parameters is not immediate. The delay in the changing of parameters is needed to ensure system stability. The application of the parameters at the start of the next time step is combined with the reset of the solver (Integrator) if needed.
For the purpose of exploring single-task loops and multi-task loops, FIG. 9 depicts the block diagrams of FIG. 7A and FIG. 8 where Method1 corresponds to the Output method 190 and Method2 corresponds to the Update method 192 . All other methods are ignored in the explanation of the loops. Simpler loops which do not include blocks that have continuous sample times are used in the example since the explanation is simpler in the context of discrete sample times and it is straight-forward to extend to continuous sample times.
In a single-tasking SimLoop, there is essentially a single execution time-line. On this time-line, each block is executed when it has a sample hit. A sample hit is defined to be an execution time instant that is an integer multiple of the block's sample time. To aid in execution, execution lists are constructed for each method type. FIG. 10 depicts the sequence of steps followed by a single-tasking execution loop. Following initialization (step 200 ), a time parameter is checked to see if the current time is less than the stop time (step 201 ). If the time is not less than the stop time, the simulation ends (step 202 ). If the time is less than the stop time, the simulation continues and the root output method execution list is executed (step 204 ). Following execution of the output method list (step 204 ) the update method execution list is executed (step 206 ). Following the performance of an integrate step ( 208 ) (the Integrate step is described in more detail below in FIG. 14 ), the time parameter is incremented by the applicable step size (step 210 ).
Blocks are arranged in the single-tasking execution lists in the sorted order as shown in FIG. 11A . A sorted list 250 is used to generate an Output method execution list 252 and an Update method execution list 254 . Referring back to the example in FIGS. 7 and 8 , the engine sequentially steps through and execute each block in the block method execution list when the execution time divided by the sample time equals an integer number (1, 2, 3, 4, etc.). At time zero (T 0 ), all the blocks are executed. This involves executing the Output methods for blocks F, E, D, A, B, and C (in this order as dictated by the sorted list) and then executing the Update methods of blocks F, E, and D (again, in this order based on the sorted list). The execution time then is then incremented by step size, which in this case is assumed to be 0.1 seconds. Execution then commences once again at the top of the loop for T=0.1 (T 0.1 ). Blocks F and E have a sample time of 0.1 seconds and have a sample hit ( 0.1÷0.1=1 , sample time is an integer multiple of the execution time), so the output block methods for Blocks F and E are executed. Block D, however, has a 1.0 second sample time and has no sample hit (0.1÷1.0=0.1, sample time is not an integer multiple of the execution time), so its output block method is not executed (essentially it is skipped). Block A, like Blocks F and E, has a 0.1 second sample time and so its output block method is executed. Blocks B and C, like Block D, have 1.0 second sample times and are skipped during this iteration of the simulation loop, which completes execution of the output block method execution list for T 0.1 .
The execution timing of the example block diagram in single task mode is shown in the first time-line of FIG. 11B . In this diagram, note that the execution-time is not synchronized with real-world time. Instead, execution time progresses as fast as it can in real-world time. The sorted list 259 is executed on the time-line 260 . The methods in the list 262 are executed at the appropriate time step 264 . Block diagram modeling software can also allow users to simulate real-world conditions by synchronizing execution time with real-world time. Such execution is illustrated in the second timing diagram of FIG. 11B . The methods 262 are implemented at a time-step 264 synchronized with real world time on the time line 270 .
In multitask mode, the engine performs execution along multiple time-lines based upon the number of block sample times used in the mode as shown in the flowchart of FIG. 13 . In the example of FIGS. 7 and 8 , the model's blocks have a sample time of either 0.1 seconds or 1.0 second. This implies that the engine runs one set of blocks along a 0.1 second time line and another set of blocks along a 1.0 second time line. In order to run in multitask mode, the execution lists are first divided on the basis of methods (as in single-tasking mode) and then subdivided again based upon block sample times. This is illustrated in FIG. 12A . The sorted list 280 is used to generate an output method execution list 282 and update method execution list 288 . The output method execution list 282 is split into two separate list execution lists 284 and 286 based on sample times. Similarly, the update method execution list 288 is divided into two update method execution lists 290 and 292 based on sample times.
The execution engine uses the divided execution lists to create multiple execution time lines. In the multitask mode the engine places a higher execution priority on the faster sample time blocks than the slower sample time blocks. This prioritization is carried out by assigning Task Identification Numbers (TIDs) to each execution list; the higher the priority, the lower the TID. For example, a TID of 0 executes at a higher priority than a TID of 1, and so forth. Furthermore, because, during execution in multitask mode, execution transitions between the faster and slower blocks, and vice-versa, the multitask mode requires rate transition blocks that allow the model to transition from blocks running at fast sample times, in our example 0.1 seconds, to slower samples times, e.g., 1.0 seconds. The rate transition blocks are required to correctly simulate how a multi-rate system would behave in a real-time environment. To provide this transition, the engine promotes rate transition blocks to the TID of the fast block for which transition is being provided, although the engine executes these rate transition blocks at their slower rate. This is why Blocks D and B appear in the 0.1 sample time output method execution list in FIG. 12A .
The execution of our example in the multi-task mode may be seen in FIG. 12B . At time T=0, the engine first executes the high priority output methods (those with TID 0 ) for Blocks F, E, D, A and B, then it executes the high priority update methods (those with TID 0 ) for Blocks F and E. After finishing the high priority blocks, the engine executes the lower priority output block methods (those with TID 1 ) for Block C, and then executes the lower priority update methods (those with TID 1 ), which, in this example, is Block D. In contrast to the single task mode, in multitask mode the engine runs through a TID inner loop to execute the output and update block methods before going on to the Integration step, as the flow chart in FIG. 13 which is discussed below illustrates.
As a result of the inner TID loop, as well as the segregated block method execution lists, the order of execution in multitask mode differs from the order of execution in single task mode. Recall for the example that in single task mode that the order of execution at T=0 is: F o , E o , D o , A o , B o , C o , F u , E u , and D u , where the subscript “o” stands for output method and the subscript “u” stands for update method. In the multitask mode, however, the order of execution at T=0 is: F o , E o , D o , A o , B o , F u , E u , C o , and D u . Notice that C o is executed in a different order in multitasking mode. This occurs because separate method execution lists (based upon sample time) are created and run in order from fastest sample time to slowest sample time. Additionally, the use of rate transition blocks restricts the connection of blocks with different rates. By requiring the insertion of these blocks into the model, the engine ensures that execution in multitask mode will follow the sorted list.
After it is finished executing the block methods for T=0, like in the single task mode, the execution time is incremented (again assume by 0.1 seconds) and execution goes to the beginning of the loop. The engine executes F o , E o , A o , F u , and E u , and the engine does not execute the block methods of Blocks D, B, and C because the current execution time is not an integer multiple of those block's sample time. The engine repeats this execution until the execution time is incremented to 1.0 seconds, whereupon execution occurs in the same manner as described for T=0. The engine repeats this overall process until the execution stop time is reached.
FIG. 12B shows two time-lines; the lower time-line 306 represents the execution order of the faster sample time blocks (Blocks A, E, and F), along with the rate transition blocks (Blocks B and D), while the top time-line 308 shows the execution order of the slower sample time block (Block C), and the rate transition (Block D) update method. The time-lines are generated from the sorted list 302 and the associated sample times 304 . The lower line, representing the faster sample times has a TID of 0, and the top line has a TID of 1. For execution time T=0, the chart shows that the engine executes the output methods for Blocks F, E, D, A, and B (designated on the chart as F o , E o , D o , A o , B o ). Then, consistent with the flow chart for the multi-tasking mode (see FIG. 13 discussed below), the engine executes the update block methods for Blocks F and E (designated F u , and E u ). Once the engine is finished with the high priority block methods, the output method for Block C (C o ) and the update method for rate transition block D (D u ) are executed. The execution time is then incremented by the step size (continue to assume 0.1 seconds) and the blocks that have a sample hit are executed. The figure shows execution of F o , E o , A o F u , and E u , which is repeated, as noted above, until execution time equals 1.0 second. Notice, like in the non-real-time case for Single-task mode, the engine does not wait for time to elapse; rather it executes block methods immediately upon completion of the previous pass through the loop.
FIG. 13 shows the overall sequence of steps taken by Simulink® in multitask mode. Following initialization (step 220 ), the output method execution list is executed for the fastest sample time (step 222 ). The update method execution list is then executed for the fastest sample time (step 224 ). A time time parameter is checked (step 225 ) to determine if the time is less than a designated stop time. If the stop time has been reached, the simulation completes (step 226 ). Otherwise, the integrate stage (step 228 ) is performed. The task ID variable is incremented (step 230 ) and compared to a parameter of the number of sample times (step 231 ). If the task ID is less than the number of sample times, the output method execution list for the methods assigned the new task Id are executed (step 232 ) followed by the execution of the update method execution list assigned the new task ID (step 234 ). The task ID variable is incremented and the process iterates with the task ID being compared to the number of sample rate times (step 231 ). When the task ID number is determined to equal the number of sample rate times, the simulation time is incremented (step 238 ) and the entire process iterates with the output method list execution list (step 222 ) being executed for the fastest sample times. The process continues until the end of simulation when the time equals the stop time (step 226 ).
In order to understand how the step size is picked within SimLoop, it is first necessary to understand the notion of a solver. The solver is a module of the execution engine that is responsible for performing two tasks: (a) determining how far execution time should be advanced between consecutive passes through the SimLoop in order to accurately trace the system's outputs, and (b) integrating the derivative of the states of the system to obtain the actual states. Based on how solvers perform the first task, they are generally classified into two basic classes: Fixed-step solvers or Variable-step solvers.
Fixed-step solvers are solvers in which the time step-size between consecutive passes through the SimLoop is a fixed quantity. The user generally explicitly specifies this quantity. These solvers are used to model types of systems that must operate within a defined time (discrete systems). For instance, an anti-lock braking system may be designed to control a car's braking system, and to execute such control in one-one hundredth (0.01) of a second so as to assure the car stops safely; if the braking system does not meet its timing constraints, the car may crash. Fixed-step solvers, therefore, are designed to help model discrete systems that have to generate a result in a fixed time period, and the fixed-step execution assures that the modeled system can generate such results.
Variable-step solvers are designed to model continuous systems where non-evenly spaced time steps are needed to simulate all significant behavior. For example, one may want to simulate the path of a bouncing ball, where it bounces, how high it bounces, and where it stops. It is known, based on experience, that the ball's bounces will not be evenly spaced, and that the height of the bounces will diminish as a result of gravity, friction, and other forces. Variable-step solvers are used for these types of continuous systems and to determine what step size to use so that the behavior of the ball will be accurately modeled.
The two broad classes of solvers are further subdivided based on the integration task they perform. There are several algorithms for carrying out numerical integration. The particular choice of the integration algorithm gives rise to the subclasses of solvers.
The difference in the conceptual definition of Fixed- and Variable-step solvers leads to the functional difference in the context of the SimLoop. The major difference between the solvers arises in the Integrate step of the SimLoop which is depicted in FIG. 14 . During the Integrate step, the Variable-step solver executes the Output and Derivative block method lists for a number of iterations that varies based on the solver subclass (i.e., the numerical integration algorithm it uses) and integration error tolerances. In a fixed-step solver, the number of iterations is fixed for a given solver subclass. Another difference between solvers arises in the Integrate phase in the context of an operation known as zero-crossing detection. Zero-crossings in the derivatives of the state generally indicate a discontinuity in the states themselves. Because discontinuities often indicate a significant change in a dynamic system, it is important to trace the system outputs precisely at such points. Otherwise, the outputs of the model could lead to false conclusions about the behavior of the system under investigation. Consider, again the example of the bouncing ball. If the point at which the ball hits the floor occurs between simulation steps, the simulated ball appears to reverse position in midair. This might lead an investigator to false conclusions about the physics of the bouncing ball. To avoid such misleading conclusions, it is important that the execution has time steps on and around the vicinity of discontinuities.
In the case of Fixed-step solvers, there is no notion of zero-crossing detection and one is not guaranteed to find all points of discontinuity. One can only keep reducing the step-size to increase the probability of hitting the discontinuity. Contrastingly, in the case of Variable-step solvers, the Integrate step explicitly includes zero-crossing detection. The execution step size is then adjusted accordingly to ensure that discontinuities are tracked accurately. To enable zero-crossing detection, blocks that can produce discontinuities instantiate a special execution method. This method registers a set of zero-crossing variables with the execution engine, each of which is a function of a state variable that can have a discontinuity. The zero-crossing function passes through zero from a positive or negative value when the corresponding discontinuity occurs. During the zero-crossing detection phase of the Integration step, the engine asks each block that has registered zero-crossing variables to update the variables for the projected time of the next time step. These variables are then checked for a change of sign since the current step. Such a change indicates the presence of a discontinuity. An iterative process then tries to narrow down the location of the discontinuity and ensure that the next few time steps (at least 2) accurately bracket the location of the discontinuity. The final difference, which is in the step-size during execution, is a direct consequence of the two previous differences in the step-size determination. In Fixed-step solvers, the step size is a known and fixed quantity. For Variable-step solvers, the step size is determined during the integration iterations and the zero-crossing detection that happens during the Integration step.
An example of the variable-step solver is shown in FIG. 14 , the derivative method execution list is executed (step 240 ) followed by the output method execution list (step 242 ). The derivative method execution list is then executed again (step 244 ) and the solver iterates between the execution of the output method execution list (step 242 ) and the execution of the derivative method execution list (step 244 ). A similar iteration loop then occurs between the execution of the output method execution list (step 246 ) and the execution of the zero-crossing method execution list (step 248 ). Note that Simulink® also includes other methods such as Projections and Jacobians in this step as needed.
While it is theoretically possible to have Variable-step solvers in the context of multitasking, such a combination is not employed in practice. This is because the step-size for such solvers can become very small making it impossible to keep up with the real-time constraint that generally goes along with multitasking execution. An added complication is that the integration step in such solvers is iterative and takes varying amounts of time at each step of the execution. Therefore, Variable-step solvers are generally used only in conjunction with the Single-Tasking SimLoop. Additionally, they are not usually employed in systems that need to operate in real-time.
When a model contains an algebraic loop, the engine calls a loop solving routine at each time step. The loop solver performs iterations and perturbations to determine the solution to the algebraic condition (if it can). One possible approach to solving the algebraic equation F(z)=0, is to use Newton's method with weak line search and rank-one updates to a Jacobian matrix of partial derivatives. Although the method is robust, it is possible to create loops for which the loop solver will not converge without a good initial guess for the algebraic states z. Special blocks are generally provided to specify an initial guess of the states in the algebraic loop.
In addition to the various forms of the SimLoop, modeling packages such as Simulink® use the output of the Link stage to compute linear models through a process generally referred to as model linearization. These linear models may be used in the SimLoop at various points in the execution of the overall model. Alternatively, the linear model may be returned to the user. The linearization process involves the use of a Jacobian method defined on blocks and numerical Jacobian algorithm.
Information related to the compiled block diagram may be presented to users in an automatically generated report. This report allows users to quickly obtain documentation of the functional description of their model. Information related to the execution of a particular model (such at the time taken to execute various portions of the model and the coverage of various portions of the model) may be obtained automatically and presented to the user as a report.
Various classes of block diagrams describe computations that can be performed on application specific computational hardware, such as a computer, microcontroller, FPGA, and custom hardware. Classes of such block diagrams include time-based block diagrams such as those found within Simulink® from the MathWorks, Inc. Natick Mass., state-based and flow diagrams such as those found within Stateflow® from the MathWorks, Inc. Natick Mass., and data-flow diagrams. A common characteristic among these various forms of block diagrams is that they define semantics on how to execute the diagram.
Historically, engineers and scientists have utilized time-based block diagram models in numerous scientific areas such as Feedback Control Theory and Signal Processing to study, design, debug, and refine dynamic systems. Dynamic systems, which are characterized by the fact that their behaviors change over time, are representative of many real-world systems. Time-based block diagram modeling has become particularly attractive over the last decade with the advent of software packages such as Simulink® from The MathWorks, Inc. of Natick, Mass. Such packages provide sophisticated software platforms with a rich suite of support tools that makes the analysis, synthesis, validation, and design of dynamic systems efficient, methodical, and cost-effective.
A dynamic system (either natural or man-made) is a system whose response at any given time is a function of its input stimuli, its current state, and the current time. Such systems range from simple to highly complex systems. Physical dynamic systems include a falling body, the rotation of the earth, bio-mechanical systems (muscles, joints, etc.), bio-chemical systems (gene expression, protein pathways), weather and climate pattern systems, etc. Examples of man-made or engineered dynamic systems include: a bouncing ball, a spring with a mass tied on one end, automobiles, airplanes, control systems in major appliances, communication networks, audio signal processing, nuclear reactors, a stock market, etc. Professionals from diverse areas such as engineering, science, education, and economics build mathematical models of dynamic systems to better understand system behavior as it changes with the progression of time. The mathematical models aid in building “better” systems, where “better” may be defined in terms of a variety of performance measures such as quality, time-to-market, cost, speed, size, power consumption, robustness, etc. The mathematical models also aid in analyzing, debugging and repairing existing systems (be it the human body or the anti-lock braking system in a car). The models may also serve educational and training purposes, e.g., to explain the basic principles governing physical systems. The models and results are often used as a scientific communication medium between humans. The term “model-based design” is used to refer to the use of block diagram models in the development, analysis, synthesis, and validation of dynamic systems.
With the modeling of complex, or even simple, dynamic systems, the likelihood exists that the resulting model will include one or more algebraic loops. Algebraic loops can be described as circular dependencies between variables. If there is a circular dependency between variables, the value of each of the variables cannot be directly computed. For example, given an example set of equations as follows:
x=y+ 2
y=−x
The values of x and y cannot be directly computed. There are two different approaches to solving these equations. The first approach is to supply educated guesses as values of each of the variables repeatedly until a solution results. However, this is an inefficient and time consuming approach that cannot provide a fixed computational load because it relies upon iteration, and is therefore not suited for, e.g., real-time applications. Alternatively, the system of equations can be partially solved algebraically. For example, solving the system into an explicit form leads to 2x=2 and y=−x, or x=1 and y=−1.
Simulink® blocks may have input ports with direct feedthrough. This means that the values of the signals entering the blocks at their input ports have to be known when the output of these blocks, or when the time of the next sample hit, is computed. More specifically, a block has direct feedthrough if its input at time, t, must be known when its output at time, t, is computed. The ports of every block in Simulink® are flagged as either having or not having direct feedthrough. Direct feedthrough characteristics become important when Simulink® generates its sorted list of blocks. For blocks without direct feedthrough ports, such as a unit delay, the block sorting is not important because the output does not depend on the current input. Sorting is crucial for efficient execution, however, for blocks with direct feedthrough ports, as the block's input signal (i.e., the output of the block directly connected thereto), must be computed prior to its output calculation. Failure to sort blocks such that these direct feedthrough relationship hold will require multiple output method evaluations to get the correct answer, resulting in inefficient execution.
Because of the requirement that input signals to direct feedthrough ports of blocks must be computed prior to obtaining an output calculation, and despite care in sorting blocks in a block diagram model, there is a tendency for algebraic loops to occur. An algebraic loop generally occurs when an input port with direct feedthrough is driven by the output of the same block, either directly, or by a feedback path through other blocks with direct feedthrough. An example of an algebraic loop is a simple scalar loop 251 as shown in FIG. 15 .
The scalar loop 251 includes a Sum Block 253 having an input u and an output z. Mathematically, the scalar loop 251 implies that the output of the Sum block 253 is an algebraic state z constrained to equal the first input u minus z (i.e. z=u−z). The solution of this simple loop is the equation “z=u/2”. However, most algebraic loops cannot be solved by inspection. It is possible to create vector algebraic loops with multiple algebraic state variables z1, z2, etc., as shown in an example block diagram model 255 of FIG. 16 .
In FIG. 16 , an Algebraic Constraint block 257 a and 257 b is a conventional way to model algebraic equations and requires specification of initial guesses. The Algebraic Constraint block 257 a and 257 b constrains its input signal F(z) to zero and outputs an algebraic state z. The Algebraic Constraint block 257 a and 257 b outputs the value necessary to produce a zero at the input. The output must affect the input through some feedback path. If the user provides a better initial guess (than the default value assumed by the solver) then the algebraic loop solver can be more efficient.
A scalar algebraic loop represents a scalar algebraic equation or constraint of the form F(z)=0, where z is the output of one of the blocks in the loop and the function F consists of the feedback path through the other blocks in the loop to the input of the block. In the simple one-block example shown in FIG. 15 , F(z)=z−(u−z). In the vector loop example shown in FIG. 16 , the equations are:
z 2 +z 1−1=0
z 2 −z 1−1=0
Algebraic loops arise when a model includes an algebraic constraint F(z)=0. This constraint might arise as a consequence of the physical interconnectivity of the system being modeled. More generally, the constraint might arise because a user is attempting to model a differential/algebraic system (DAE).
When a model contains an algebraic loop, block diagram programs such as Simulink® call a loop solving routine at each time step. The loop solver performs iterations to determine the solution to the problem (if it can). As a result, models with algebraic loops have a variable computational load and no set response time.
To solve F(z)=0, a conventional loop solver, such as the one found in Simulink®, utilizes Newton's method with weak line search and rank-one updates to a Jacobian matrix of partial derivatives. Although the method is robust, it is possible to create algebraic loops for which the loop solver will not converge without a good initial guess for the algebraic states z, especially if the loop contains discontinuities. A user can specify an initial guess for a line in an algebraic loop by placing an initial condition (IC) block (which is normally used to specify an initial condition for a signal) on that line. As shown above, another way to specify an initial guess for a line in an algebraic loop is to use an Algebraic Constraint block. Thus, there is a recommendation that whenever possible, an IC block or an Algebraic Constraint block be used to specify an initial guess for the algebraic state variables in a loop. Alternatively, a user must try to solve the algebraic loop, or re-organize the blocks to eliminate the algebraic loop while still maintaining functionality. However, if not prohibitively difficult, this also can be time consuming, especially in complex systems, because of the likelihood that there are a significant number of algebraic loops to either solve or eliminate.
Artificial algebraic loops are of a different origin but have a similar manifestation. Artificial algebraic loops arise when the model designer groups blocks into inseparable units of computation that have ports with direct feedthrough and, as a result, become part of an algebraic loop. If the blocks could be executed individually, no algebraic loop would be present, therefore, the algebraic loop is deemed artificial.
To illustrate, consider the example later discussed in FIG. 18 . If an example sub-system 422 is virtual (i.e., it has no implications with respect to the execution order of its internal methods), the constituents can be executed separately from one another. This allows a regular execution order. First, a Constant 421 is executed to produce its output (A). Because a Sum block 426 needs one more input (E) before it can compute its output, a Unit Delay block 432 in the Sub-system 422 computes a unit delay output (D). A Gain block 424 can then compute a gain output (E) and this allows the Sum block 426 to compute the sum output (B). Finally, a Gain block 430 computes the gain output (C).
When, however, the Sub-system 422 is required to be an inseparable unit of computation so that individual output, update, etc. methods can be defined, i.e., it is nonvirtual, the above execution order becomes invalid because the computation of the output of the Sub-system 422 constituents, i.e., the Gain 430 and Unit Delay 432 , is interspersed with the computation of the output of other blocks. In such instances, the Gain 430 computes its output immediately before or after the Unit Delay 432 computes its output, thus the input to Sub-system 422 has to be available when its output is computed. Otherwise, the Gain 430 would compute its output using an incorrect value. Therefore, the input port In 1 428 of Sub-system 422 has direct feedthrough and the corresponding input-output dependency leads to an algebraic loop that is considered artificial because the loop is induced by execution constraints.
SUMMARY OF THE INVENTION
There is a need for an efficient method for resolving artificial algebraic loops automatically. The present invention is directed toward further solutions to address this need.
In accordance with one embodiment of the present invention, in an electronic device, a method of resolving an algebraic loop includes providing an executable process having a plurality of functions. The process is identified as to whether blocks with direct feedthrough ports caused by execution constraints are present. For such blocks, an artificial algebraic loop may exist in the process, and an artificial algebraic loop solution is implemented that modifies a manner by which the plurality of functions forming the potential artificial algebraic loop execute.
In accordance with aspects of the present invention, the artificial algebraic loop solution includes rerouting at least one of a model update function, a derivative function, and a zero-crossing function to execute a model output function to obtain output from the direct feedthrough plurality of functions and subsequently executing the remaining model update function, derivative function, and/or zero-crossing function to compute variables contained within the plurality of functions. The rerouted model update, derivative, and zero-crossing functions compute values of variables of direct feedthrough functions using the correct input. The artificial algebraic loop solution includes the alternatives: executing model output function multiple times, or splitting the output method into several sub-output methods, such that a preceding execution provides an updated input variable and a subsequent execution computes the values of variables of direct feedthrough functions that require this input to provide at least one of a desired output and an internal variable; inserting a delay function into the at least one potential artificial algebraic loop and executing the executable process; switching the order of direct feedthrough functions and non-direct feedthrough functions to prevent the occurrence of the artificial algebraic loop, and/or breaking up the inseparable unit of execution into two parts that are each inseparable.
In accordance with further aspects of the present invention, identifying whether the process includes at least one potential artificial algebraic loop includes determining whether there is at least one path of execution in an inseparable unit of execution wherein a non-direct feedthrough element follows a direct feedthrough element prior to calculation of an output. Providing the executable process having a plurality of functions includes providing at least one sub-system containing the at least one artificial algebraic loop. The at least one sub-system can include at least one nonvirtual sub-system, and/or at least one direct-feedthrough sub-system requiring at least one input variable for execution. The artificial algebraic loop solution can include separating a direct feedthrough part from a remainder of the original content to prevent the occurrence of the potential artificial algebraic loop.
In accordance with further aspects of the present invention, the method further includes representing the executable process using a block diagram format; representing the executable process using an equation format; identifying an execution order for the plurality of functions within the artificial algebraic loop; and/or executing the plurality of functions based at least in part on whether each of the plurality of functions contains an update call, a derivative call, and a zero-crossing call.
In accordance with one embodiment of the present invention, a medium holding computer executable steps for carrying out a method of resolving an algebraic loop is provided. The method includes providing an executable process having a plurality of functions; identifying whether the process includes at least one potential artificial algebraic loop; and if at least one potential artificial algebraic loop exists in the process, implementing an artificial algebraic loop solution that modifies a manner by which the plurality of functions forming the artificial algebraic loop execute.
In accordance with one embodiment of the present invention, a system for identifying and resolving an algebraic loop in a process includes an identification mechanism for identifying whether the process includes at least one potential artificial algebraic loop, and an artificial algebraic loop solution for resolving the algebraic loop. The artificial algebraic loop solution modifies a manner by which the plurality of functions forming the artificial algebraic loop execute.
In accordance with aspects of the present invention, the artificial algebraic loop solution includes execution of at least one of a model update function, a derivative function, and a zero-crossing function that is rerouted to compute the output of variables contained within the plurality of functions that belong to the direct feedthrough part and subsequently executing the remainder of the model update function, derivative function, and zero-crossing function, to operate on the now correctly computed output from the plurality of functions that belong to the direct feedthrough portion. The artificial algebraic loop solution can include execution of a model output function twice, such that a first execution provides an updated input variable and a second execution provides at least one of a desired output and an internal variable; insertion of a delay function prior to the at least one potential artificial algebraic loop and execution of the executable process; and/or switching of the order of direct feedthrough functions and non-direct feedthrough functions to prevent the occurrence of the artificial algebraic loop.
In accordance with further aspects of the present invention, the identification mechanism determines whether there is at least one path of execution wherein a non-direct feedthrough element follows a direct feedthrough element prior to calculation of an output. The process can include at least one sub-system containing the at least one artificial algebraic loop. The at least one sub-system can include at least one nonvirtual sub-system, and/or at least one direct-feedthrough sub-system requiring at least one input variable for execution. The artificial algebraic loop solution can further include a separation of a direct feedthrough part from a remainder of the original content to prevent the occurrence of the potential artificial algebraic loop.
In accordance with further aspects of the present invention, the system can further include the executable process represented in a block diagram format, and/or the executable process represented in an equation format. The system can have an execution order for the plurality of functions within the artificial algebraic loop. The execution order can be for executing the plurality of functions based at least in part on whether each of the plurality of functions contains an update call, a derivative call, and a zero-crossing call.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become better understood with reference to the following description and accompanying drawings, wherein:
FIG. 1A depicts a dynamic system described with ordinary differential equations (ODE);
FIG. 1B depicts a dynamic system described with difference equations;
FIG. 1C depicts a dynamic system described with algebraic equations;
FIG. 2 depicts components of a basic block diagram;
FIG. 3 depicts the desired behavior of an integrator block;
FIG. 4 is a flow chart of the sequence of steps used to perform simulation of the block diagram;
FIG. 5 depicts the replacement of a collection of blocks in a block diagram with an accumulator block;
FIG. 6A depicts a block diagram and its associated directed graph;
FIG. 6B depicts a linear sorted list generated from the directed graph of FIG. 6A ;
FIG. 7A depicts an abstract example of a block diagram being executed;
FIG. 7B depicts an abstract view of the execution methods instantiated by the blocks depicted in FIG. 7A ;
FIG. 7C depicts a sorted list generated from the data dependencies between blocks of FIG. 7A ;
FIG. 8 depicts a multi-rate system;
FIG. 9 depicts the block diagram of FIG. 7A and FIG. 8 with associated methods added to the blocks;
FIG. 10 is a flowchart of the sequence of steps followed by a single-tasking execution loop;
FIG. 11A depicts the creation of execution lists from sorted lists in single task mode;
FIG. 11B depicts the execution timing of block diagrams in single task mode in timelines synchronized and non-synchronized with real world time;
FIG. 12A depicts the creation of execution lists from sorted lists in multi-task mode;
FIG. 12B depicts the execution timing of block diagrams in multi-task mode;
FIG. 13 is a flowchart of the overall sequence of steps taken by Simulink® in multi-task mode;
FIG. 14 is a flowchart of the sequence of steps followed by a variable-step solver;
FIG. 15 is a diagrammatic illustration of an algebraic loop, as is known in the art;
FIG. 16 is a diagrammatic illustration of a conventional Algebraic Constraint block for resolving artificial algebraic loops, as is known in the art;
FIG. 17 is a diagrammatic illustration of an electronic device for executing the method of the present invention;
FIG. 18 is a diagrammatic illustration of an artificial algebraic loop structured as a sub-system, according to one aspect of the present invention;
FIGS. 19A , 19 B, and 19 C are schematic illustrations showing execution stages of a model simulation implementing the artificial algebraic loop solution, according to one aspect of the present invention;
FIG. 20 is a flow chart depicting a method of resolving an artificial algebraic loop, according to one aspect of the present invention;
FIG. 21A is a flow chart depicting another method of resolving an artificial algebraic loop, according to one aspect of the present invention;
FIG. 21B is a diagrammatic illustration of a sub-system in accordance with aspects of the present invention;
FIG. 22 is a flow chart depicting another method of resolving an artificial algebraic loop, according to one aspect of the present invention; and
FIG. 23 is a flow chart depicting an example embodiment of resolving an artificial algebraic loop, according to one aspect of the present invention.
DETAILED DESCRIPTION
An illustrative embodiment of the present invention relates to an automated solution for addressing artificial algebraic loops in a block diagram or text or equation based execution, simulation, or modeling system. The automated solution involves scanning a model to identify each occurrence of a potential artificial algebraic loop. Once each potential artificial algebraic loop is identified, the present invention partitions the potential artificial algebraic loop in a regular part and a direct feedthrough part, the output of the latter is computed in the update phase of the simulation to obtain a correct output of all blocks involved. More specifically, when the blocks of the model are tasked with calculating an output, the present invention disregards the blocks in the direct feedthrough portion. Then, when tasked to update the state, the blocks in the direct feedthrough part first compute their output to obtain correct output values of all blocks in the model.
The phrase “potential artificial algebraic loop” refers to a situation that is context independent. In other words, the potential artificial algebraic loop represents a situation wherein there is a potential or possibility that given the occurrence of certain events or execution orders, an artificial algebraic loop will exist, having an inseparable unit of execution. An actual artificial algebraic loop can only emerge when the context is available, such as if the output of an inseparable unit of execution is related to its input through a direct feedthrough path.
As utilized herein, the term “function” encompasses the functionality of any combination of elemental computations, including blocks of a block diagram, equations, state variables, or any other element having functional attributes as understood by one of ordinary skill in the art.
The analysis of the present invention, studies each inseparable unit of execution individually and without knowledge of how the unit of execution is or will be utilized, i.e, the context, and determines whether an artificial algebraic loop may arise. If there is a potential for an artificial algebraic loop to occur, the artificial algebraic loop solution can be employed.
There may be reasons to refrain from applying the artificial algebraic loop solution, however, when the potential exists after the unit of inseparable execution connects with the rest of the system. Therefore, a decision stage is required before the solution is applied which, in its basic form, can be a flag set by the user. This decision criterion can be made as sophisticated as desired, e.g., by incorporating context knowledge. In such an instance, the artificial algebraic loop solution is only applied when a potential artificial algebraic loop is found if analysis of the context shows an artificial algebraic loop will, in fact, emerge. This, of course, requires knowledge of the context of a unit of inseparable execution, which, in general, may not be available. It should be noted that the present invention anticipates such an arrangement, and makes the assumption that such an analysis is either non-existent, or has resulted in the determination that there is in fact a potential artificial algebraic loop that must be resolved.
FIGS. 17 through 23 , wherein like parts are designated by like reference numerals throughout, illustrate example embodiments of an artificial algebraic loop resolver according to the present invention. Although the present invention will be described with reference to the example embodiments illustrated in the figures, it should be understood that many alternative forms can embody the present invention. One of ordinary skill in the art will additionally appreciate different ways to alter the parameters of the embodiments disclosed in a manner still in keeping with the spirit and scope of the present invention.
As stated previously, the present invention is applicable to both text or equation based model execution and block diagram or otherwise graphical language based model execution. However, for purposes of clarity, the present invention will be described with reference to a block diagram embodiment. One of ordinary skill in the art will appreciate, however, that a block of a block diagram is simply a representation of one or more variables, inputs, outputs, equations, and the like that can be expressed in text or equation form. Thus, any reference herein to a “block” likewise applies to a textual equivalent, and thus is not limiting the present invention to operation only with block diagram formats.
As mentioned previously, block diagrams are a set of graphical connections between blocks to model the above-described dynamic systems. The individual blocks in a block diagram represent mathematical operations and output a result. Some Simulink® blocks have input ports with direct feedthrough. A block input port has direct feedthrough if the block's functionality that requires input at time, t, to be known when the output at time, t, is computed. Block input ports with direct feedthrough , in some instances, are identified by the simulation program. For example, Simulink® flags each block input port as either having or not having direct feedthrough. Some examples of blocks with direct feedthrough input ports include the Math Function block, the Gain block, the Integrator block's initial condition ports, the Product block, the State-Space block when there is a nonzero D matrix, the Sum block, the Transfer Fen block when the numerator and denominator are of the same order, and the Zero-Pole block when there are as many zeros as poles. These blocks and functions, and equivalent or additional blocks and functions not specifically mentioned herein, can become part of a set of inseparable computations to create artificial algebraic loops that are resolvable by the method of the present invention.
FIG. 17 illustrates one example embodiment of an electronic device 310 suitable for practicing the illustrative embodiments of the present invention. The electronic device 310 is representative of a number of different technologies, such as personal computers (PCs), laptop computers, workstations, personal digital assistants (PDAs), Internet appliances, cellular telephones, and the like. In the illustrated embodiment, the electronic device 310 includes a central processing unit (CPU) 311 and a display device 312 . The display device 312 enables the electronic device 310 to communicate directly with a user through a visual display. The electronic device 310 further includes a keyboard 313 and a mouse 314 . Other potential input devices not depicted include a stylus, trackball, joystick, touch pad, touch screen, and the like. The electronic device 310 includes primary storage 315 and secondary storage 316 for storing data and instructions. The storage devices 315 and 316 can include such technologies as a floppy drive, hard drive, tape drive, optical drive, read only memory (ROM), random access memory (RAM), and the like. Applications such as browsers, JAVA virtual machines, and other utilities and applications can be resident on one or both of the storage devices 315 and 316 . The electronic device 310 can also include a network interface 317 for communicating with one or more electronic devices external to the electronic device 310 depicted. A modem (not shown) is one form of establishing a connection with an external electronic device or network. The CPU 311 has either internally, or externally, attached thereto one or more of the aforementioned components. In addition to applications previously mentioned, modeling applications, such as Simulink® 318 , can be installed and operated on the electronic device 310 .
It should be noted that the electronic device 310 is merely representative of a structure for implementing the present invention. However, one of ordinary skill in the art will appreciate that the present invention is not limited to implementation on only the described device 310 . Other implementations can be utilized, including an implementation based partially or entirely in embedded code, where no user inputs or display devices are necessary. Rather, a processor can communicate directly with another processor or other device.
Turning now to a description of the present invention, FIG. 18 is a diagrammatic illustration of an artificial algebraic loop 420 . The example artificial algebraic loop 420 includes an Atomic Sub-system 422 , a Gain 424 , and a Sum 426 . The Atomic Sub-system 422 further includes an Input 428 , supplied to a Sub-system Gain 430 , which feeds to a Unit Delay 432 , and ultimately to an Output 434 . It should be noted that the Unit Delay 432 , or other delay functions as utilized herein, can include time delays and memory function delays, as understood by one of ordinary skill in the art. Initially, a constant 421 feeds the Sum 426 .
As previously stated, artificial algebraic loops result from a grouping of equations. Graphically, block diagram model simulators, such as Simulink®, show groupings that are part of a potential artificial algebraic loop as nonvirtual sub-systems, one of which is the Atomic Sub-system 422 .
As shown, the Atomic Sub-system 422 contains the Gain 430 computation and the Unit Delay 432 computation. The combination of the Gain 430 and the Unit Delay 432 as shown creates the problem of the artificial algebraic loop because there is a dependence of the system input on the system's own output. More specifically, because the Sub-system 422 is an inseparable unit, the output of the Gain 430 and the output of the Unit Delay 432 have to be computed immediately following one another. For the Gain 430 to compute the correct value, the input to the Gain 430 is required. Thus, when the output of Sub-system 422 is to be computed, the output of Unit Delay 432 has to be computed as well as the output of Gain 430 , and, therefore, the input has to be available as well.
FIGS. 19A , 19 B, and 19 C are diagrammatic illustrations of the Atomic Sub-system 422 of FIG. 18 that illustrate the sequence of calculations at one time step highlighting the existence of an artificial algebraic loop, and the corresponding resolution of the artificial algebraic loop provided by the present invention.
At the initial stage, the values of the state block Unit Delay 432 and a source block Input 438 are made available. The result is shown in the FIG. 19A . First, the value (a value of 1.0) of the source block Input 438 is computed. This value (1.0) makes one of the inputs to the Sum 426 known. Because at this point the other input to the Sum 426 in the form of the output from the Gain 424 has not been calculated.
The output of the atomic Sub-system 422 , and the output at output Block 436 , is computed next. The Unit Delay 432 element is requested to produce its output (a value of 1.0), producing the value of the Output 434 . This value is processed by the Gain 424 to compute the other input of the Sum 426 . At this time, the Sum 426 has both input values (each value being 1.0). The Sum 426 calculates its output, a value of 2.0.
At this point, all blocks at the top level (Constant 421 , Sub-system 422 , Gain 424 , and Sum 426 ) have been requested to compute their outputs. However, the value of the Gain 430 in the Sub-system 422 has either not been computed correctly, or not been computed at all. The Gain 430 currently indicates a value of 1.0. Thus, when the state of Unit Delay 432 is now updated, the incorrect value (1.0) is used. The state of the blocks as shown in FIG. 19A , thus, illustrates the result of the existence of the artificial algebraic loop 420 .
The artificial algebraic loop resolver of the present invention resolves the problem of the incorrect input to the Unit Delay 432 by first computing the output of the Gain 430 before updating Unit Delay 432 . FIG. 19B shows how the update to the Unit Delay 432 now results in the value 2.0 being input to the Unit Delay 432 . When the Unit Delay 432 is called to update, the Unit Delay 432 now uses the correct input value of 2.0. FIG. 19C shows the Unit Delay 432 receiving the value of 2.0 as an input and using that value to complete the delay function, as indicated by the “2.0” shown within the box outline of the Unit Delay 432 .
FIG. 20 illustrates a flowchart summarizing one embodiment of the present invention that leads to the result as depicted in FIGS. 19A through 19C . A user first creates or obtains a model execution in a text or equation based, or block diagram, or other graphical language, based format (step 650 ). In refining the model simulation, the user can take advantage of the artificial algebraic loop resolver. More specifically, the user activates the artificial algebraic loop resolver (step 652 ).
The artificial algebraic loop resolver identifies the existence of potential artificial algebraic loops (step 654 ) by tracing blocks with direct feedthrough in inseparable execution units (i.e., nonvirtual subsystem) from the input to the output. If along the processing path, a non-direct feedthrough block is encountered, the path up to the non-direct feedthrough block is considered to be part of a potential artificial algebraic loop and identified as part of the direct feedthrough portion of the inseparable execution unit. If a trace of the direct feedthrough blocks reaches an output, though, then the inseparable unit has a direct feedthrough port. In this instance, the algebraic loop is not artificial.
Once all of the potential artificial algebraic loops are found, they are each broken out into synthesized sub-systems (step 656 ). The synthesized sub-systems are generated based on the input port that connects with the blocks. If they can be traced to multiple input ports (by both forward and backward propagation), they are moved into the sub-system that belongs to the input port with lowest index.
It should be noted that the above steps, and the invention in general, can be implemented as an iterative process. The user, or an algorithm or processor, can repeat the analysis of a system, seeking out and resolving potential artificial algebraic loops with each iteration to arrive at a more efficient simulation.
The synthesized sub-systems register the need for invocation during the update, derivative, or zero-crossing stages of an execution. When triggered, the synthesized sub-systems compute the output of the contained blocks. Because these sub-systems are moved to the top of the update call list, and therefore enforced to be called before the rest of the blocks in the inseparable unit, the output of the direct feedthrough portion is computed before the update of state elements, such as the Unit Delay, are executed (step 658 ). The artificial algebraic loop resolver thus operates to compute the output of the inseparable direct feedthrough portion prior to any update of the model simulation.
The artificial algebraic loop resolver of the present invention is not limited to identifying artificial algebraic loops, partitioning them off into sub-systems, and requiring an update call prior to completing an output call. In addition, the artificial algebraic loop resolver can be modified to provide alternate solutions for artificial algebraic loops. Some example alternate solutions are provided below.
FIG. 21A illustrates the implementation of another embodiment of the artificial algebraic loop resolver of the present invention. A user first creates or obtains a model execution in a text or equation based or block diagram based format (step 770 ). In refining the model execution, the user can again take advantage of the artificial algebraic loop resolver. The artificial algebraic loop resolver is activated, either by the user or automatically (step 772 ). The artificial algebraic loop resolver identifies the existence of potential artificial algebraic loops by identifying input ports with direct feedthrough that could be driven by the output of the same block, either directly, or by a feedback path through other blocks with direct feedthrough (step 774 ).
Here, the algebraic loop analysis differentiates between ports. Instead of setting a generic direct feedthrough flag for each input port, a record is made of which output ports have a direct feedthrough path from each of the input ports. This allows inclusion of artificial algebraic loops with actual direct feedthrough within the set of inseparable computations (step 776 ). So, the artificial algebraic loop is not required to have a non direct feedthrough block as part of the loop. The artificiality of the artificial algebraic loop stems from the routing of input signals to particular output ports in a set of blocks with inseparable execution.
To illustrate, FIG. 21B shows an example diagrammatic illustration of a Sub-system 790 . The Sub-system 790 includes a first input 791 and a second input 792 , each leading to a first Gain 793 and a second Gain 794 , respectively. The first Gain 793 and second Gain 794 have a first output 795 and a second output 796 , respectively. An input 797 to the Sub-system 790 leads to an output 798 , and a Gain 799 is further provided on the path to input to the Sub-system 790 .
Both inputs of the Sub-system 790 have direct feedthrough, making the Sub-system 790 an inseparable unit of computation, i.e., an atomic sub-system, and also resulting in an algebraic loop. This algebraic loop is not present if the constituents of the Sub-system 790 are executed interspersed with the other blocks in the system, in particular the Gain 799 .
Multiple calls to evaluate the output of the set of inseparable units of computation (step 778 ) during the output computation stage of the simulation allows a solution to the system illustrated in FIG. 21B . In general, more than two calls may be required, and analysis of how the Sub-system 790 is connected can provide the required number of calls.
Those of ordinary skill in the art will recognize the opportunity for improved efficiency by selectively executing the constituents of the inseparable unit of the Sub-system 790 . For example, the first time the Sub-system 790 is executed, only the first output 795 of the first Gain 793 needs to be computed, while the second call only requires computation of the second output 796 of the second Gain 794 . The method to determine the number of required calls to compute the output can be extended to provide information about which input-output relation needs to be evaluated. The evaluation, in turn, provides the required information to implement the more efficient selective execution of constituents.
In general, the unit of inseparable execution may have to be executed more than twice to solve an artificial algebraic loop. Unlike regular algebraic loops that are solved by iteration, the number of iterations of an artificial algebraic loop can be determined a priori, which leads to fixed and determined execution times (a necessity for, e.g., real-time simulation). The number of times the unit of inseparable execution needs to be called can be derived by analysis of the number of times parts of the unit of inseparable execution are being executed interspersed by other computations when not considered inseparable. The number of times parts of the consecutive execution are called equals the number of times the unit has to be called when an inseparable execution is enforced.
FIG. 22 illustrates the implementation of another embodiment of the artificial algebraic loop resolver of the present invention. A user first creates or obtains a model execution in a text or equation based, or block diagram based format (step 880 ). The artificial algebraic loop resolver is then activated, either by a user or automatically (step 882 ). The artificial algebraic loop resolver identifies the existence of potential artificial algebraic loops by identifying input ports with direct feedthrough that are connected to the output of the same block, either directly, or by a path through other blocks with direct feedthrough (step 884 ). Once all of the artificial algebraic loops are found they are each broken out into separate sub-systems (step 886 ). More specifically, the artificial algebraic loop is essentially eliminated by running the output multiple times. To increase implementation efficiency the direct feedthrough paths can be broken up into separate synthesized sub-systems and marking the output ports to which direct feedthrough paths exist from each input port. This is different from the embodiment of FIG. 20 where each input port had a blanket direct feedthrough tag. In the current case, the loop is split apart into separate sub-systems. Each of the sub-systems is then instructed to run the sub-system execution every time that an output is requested (step 888 ). As previously noted, running the sub-system can be implemented by execution of all or part of the constituents contained within the sub-system. The artificial algebraic loop resolver of this embodiment thus operates to eliminate the update, derivative, and zero-crossing requirement and rely on the individual outputs of each component. This arrangement does require additional function calls to the model execution.
The described algorithms apply directly to handling artificial algebraic loops that emerge because of continuous state as embodied by an Integrator block instead of or in addition to discrete state as embodied by Unit Delay blocks or other discrete state or delay blocks. In the instance of continuous state, the output of the direct feedthrough portion of inseparable computations has to be computed before the continuous state blocks are called to evaluate their derivatives, which is analogous to the update call of unit delay blocks. Therefore, the sub-systems with direct feedthrough parts are synthesized analogously to the discrete event state and now register the need for invocation during the derivative stage of a simulation. In response to the derivative call the synthesized sub-systems evaluate the output of their blocks. Since synthesized blocks are moved to the top of the derivative call list, these output values are first computed before any derivative evaluation of continuous states.
In instances where no discrete states are present in the set of inseparable computations, the synthesized direct feedthrough sub-system does not need to register an invocation during the update stage of a simulation. A special case exists, though, when some of the direct feedthrough computations have a non-continuous sample time. In such an instance, the output will not be computed during minor time steps, thus computing the output of the blocks in the derivative stage fails. The synthesized sub-system, therefore, also registers an invocation during the update stage when it contains blocks with a non-continuous sample time.
Similarly, blocks with zero-crossing detection may be present. These blocks are called to evaluate whether the function they represent crosses zero. Because these evaluations are independent of the update and derivative stages, correct computation of the zero-crossings also requires computing the output of the synthesized sub-system with direct feedthrough blocks. Therefore, when blocks that register zero-crossing functionality are present in the synthesized sub-system or in the set of inseparable blocks of computation, the synthesized sub-system registers an invocation to compute its output during the zero-crossing stage.
FIG. 23 illustrates still another embodiment of the present invention that shows some of the above-described implementation alternatives. A user first creates or obtains a model simulation in a text or equation based, or block diagram based format (step 920 ). In refining the model simulation, the user can take advantage of the artificial algebraic loop resolver. More specifically, a determination is made as to whether there is an algebraic relationship between input and output, thus determining whether there is a potential artificial algebraic loop (step 922 ) depending on how the block is used. The artificial algebraic loop resolver identifies the existence of potential artificial algebraic loops by tracing blocks with direct feedthrough in inseparable execution units from the input to the output. If along the processing path, a non-direct feedthrough block is encountered, the path up to the non-direct feedthrough block is considered to be part of a potential artificial algebraic loop and identified as part of the direct feedthrough portion of the inseparable execution unit. Certain model optimization methods may require dependency evaluations to extend the direct feedthrough analysis and include blocks other than those on the direct forward path (i.e., branched dependencies). If a trace of the direct feedthrough blocks reaches an output, though, then the inseparable unit has a direct feedthrough port.
If there is not an algebraic relationship (i.e., there is a potential artificial algebraic loop) a flag is set on all traversed direct feedthrough components and components connected to flagged blocks (step 924 ). If there is an algebraic relationship, or after the flags are set on the direct feedthrough components, all flagged blocks are moved into a synthesized atomic sub-system (step 926 ). The synthesized atomic sub-systems are generated based on the input port that connects with the blocks. If they can be traced to multiple input ports (by both forward and backward propagation), they are moved into the sub-system that belongs to the input port with lowest index.
Once all of the synthesized atomic sub-systems are defined, the different variations on execution order are addressed. For each sub-system, a determination is made as to whether the synthesized sub-system contains blocks with a discrete sample time (step 928 ). If there are no such non-continuous blocks, a determination is made as to whether blocks at the synthesized sub-system level have updates (step 930 ). If the blocks do have updates, or if the synthesized sub-system contains non-continuous blocks, an update call is registered for the synthesized sub-system (step 932 ).
If there are no blocks with updates at the synthesized sub-system level, or after the update call is registered, a determination is made as to whether blocks at the synthesized sub-system level have derivatives (step 934 ). If the blocks have derivatives, a derivative call is registered for the synthesized sub-system (step 936 ).
If the blocks do not have derivatives, or after the derivative call is registered, a determination is made as to whether blocks at the synthesized sub-system level have zero-crossings (step 938 ). If there are zero-crossings, a zero-crossing call is registered for the synthesized sub-system (step 940 ).
Once all of the above determinations are complete, and appropriate registrations are made, all blocks are placed in the synthesized sub-system and invoked during the specified phases of the execution based on update, derivative, and zero-crossing registrations (step 942 ).
Still another alternative of the present invention involves the introduction of an additional delay function in the loop. This delay can either be a fixed time delay or of a variable nature. In case of a fixed time delay, a relatively small value has to be chosen in order not to substantially affect dynamic behavior. Determining the delay time is not trivial as it relates to the time constant of the artificial algebraic loop as well as time constants of the rest of the system. The use of such a delay, however, introduces a time constant that is, by requirement, much smaller than that of the artificial algebraic loop, and, therefore, increases the computational complexity of solving the loop significantly.
A further alternative includes use of a variable time delay introduced in the artificial algebraic loop. For example, in Simulink®, a Memory block can be applied. The Memory block delays the input by one integration step. This also adds considerably to the computational complexity but circumvents the need to analyze the artificial algebraic loop to decide what is a relatively small time delay value that holds across different operation regimes. Here, the variable delay time adapts to the solver step.
Thus, the present invention relates to an automated solution for addressing artificial algebraic loops in a block diagram or any graphical based language or text or equation based execution, simulation, or modeling system that facilitates execution. The automated solution involves scanning a simulation model to identify each occurrence of a potential artificial algebraic loop. Once each potential artificial algebraic loop is identified, the present invention partitions the inseparable parts of the potential artificial algebraic loop in a regular part and a direct feedthrough part. The output of the latter is computed in the alternate phases of the execution to obtain a correct output of all blocks involved. Determinations and registrations are made as to the proper execution phases for having appropriately computed variables. Then, when tasked to update the model state, compute derivatives, or evaluate zero-crossings, the blocks in the direct feedthrough part first compute their output to obtain correct output values of all blocks in the model.
Numerous modifications and alternative embodiments of the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. Details of the structure may vary substantially without departing from the spirit of the present invention, and exclusive use of all modifications that come within the scope of the appended claims is reserved. It is intended that the present invention be limited only to the extent required by the appended claims and the applicable rules of law.
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A method and apparatus for resolving artificial algebraic loops in model executions include providing an executable process having a plurality of functions. An analysis step identifies whether the process includes at least one potential artificial algebraic loop. If at least one potential artificial algebraic loop exists in the process, an artificial algebraic loop solution manipulates the order or manner by which the functions are executed to eliminate or otherwise resolve the artificial algebraic loop.
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This application is a continuation-in-part of U.S. application Ser. No. 371,837 filed Apr. 26, 1982, now abandoned.
FIELD OF THE INVENTION
The present invention relates to a process for manufacturing a semiconductor chip carrier wherein the signal leads are accurately positioned by temporary attachment among themselves or to a bus.
THE PRIOR ART
In the formation of ceramic chip carriers, lead frames are normally bonded to the ceramic substrate by well-known methods with subsequent connections being made to the leads of the lead frame from appropriate pads on semiconductor chips secured to the ceramic substrate. These connections from the pads on the chip to the leads of the lead frame are made manually or by means of automatic wire bonding machinery or by mass bonding techniques using "spider" tape. The automatic wire bonding machinery is normally computer operated on an x-y coordinate basis and it is therefore necessary that the leads of the lead frame be accurately positioned on the substrate so that wiring is run from pads on the semiconductor chip to the appropriate lead on the lead frame. Due to the fact that leads are thin and have high resistance, it has been necessary in prior art lead frames to use a plurality of leads to provide power and ground voltages to the appropriate pads on the chip. Since the number of leads in the lead frame is limited, the number of signal connections is thus reduced. Another problem of the prior art is that of providing shielding against interference between adjacent signal leads.
There is disclosed in U.S. Pat. No. 4,362,902 a copper oxide surfaced lead frame for manufacturing a semiconductor chip carrier, the lead frame having a planar surface which is to be bonded to a ceramic substrate, the lead frame comprising a plurality of outer leads extending to a plurality of locations about the periphery of the lead frame and a plurality of signal leads extending from the outer leads toward the center of the lead frame, each signal lead having a first end attached to a respective outer lead and a second end attached to support means toward the center of the lead frame. A similar scheme is disclosed in U.S. Pat. No. 4,408,281; both utilize support means in the form of an integral common rim overlying the substrate. A related scheme is disclosed in U.S. Pat. No. 4,445,271, which further discloses a ground pad attached to the support rim in the center of the lead frame. In all of the above schemes, the common rim is removed after bonding the lead frame to the substrate.
SUMMARY OF THE INVENTION
According to the instant invention, therefore, a lead frame for manufacturing a semiconductor chip carrier is characterized in that the support means is a ground bus which is to be bonded to said ceramic substrate, the ground bus having a planar surface which is coplanar with the planar surface of the lead frame. Each signal lead having a neck portion proximate to the second end, the neck portion being of smaller cross section than the rest of the signal lead, the neck portion being recessed from said planar surface, whereby, upon bonding the lead frame to the substrate, the neck portion will not bond thereto. The neck portions may be fused by heating, which is the preferred method where the lead frame has a copper oxide surface, or by passing an electric current selectively through the neck portions, causing them to melt in the manner of a fusible link.
The invention therefore assures that the second ends of all signal leads will be accurately spaced relative to each other during the bonding process. As the neck portions are fused to leave gaps, the need for removing the support means is eliminated. As the support means is in the form of a ground bus, the need for discrete ground leads for the chip is eliminated. The provision of ground leads which alternate with the signal leads and extend from the ground bus toward the outer leads, with fusible links thereat, further provides for interference shielding between signal leads. A power bus and ground pad for mounting the semiconductor chip may be similarly incorporated in the lead frame with fusible links between the power bus and the ground bus, and between the power bus and ground pad.
The lead frame of the present invention thus provides several advantages over prior lead frames in a single package, and the chip carrier using same can be manufactured in a one-step process which simultaneously bonds the frame to a ceramic substrate and separates the component circuit parts by fusing links therebetween.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of the lead frame in strip form.
FIG. 2 is a plan view of a finished chip carrier.
FIG. 3 is a perspective of a portion of the lead frame prior to bonding and melting the fusible links.
FIG. 4 is a plan view of part of the lead frame on the substrate prior to bonding and melting the fusible links.
FIG. 5 is a section view taken along line 5--5 of FIG. 4.
FIG. 6 is a plan view of part of the lead frame on the substrate after bonding and melting the fusible links.
FIG. 7 is a section view taken along line 7--7 of FIG. 6.
FIG. 8 is a section view similar to FIG. 7 after placing a semiconductor chip and performing wire bonding.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 depicts the lead frame 10 of the present invention as manufactured integrally with carrier strip 14. The stippled portions as well as the solid black portions represent copper sheet; a ground pad 42 (shown in FIG. 2) has been deleted from this view for clarity. Salient features of the lead frame 10 are the outer leads 17 having pads 18, signal leads 19, and ground leads 24 which alternate with signal leads 19. All signal leads 19 and ground leads 24 extend from pads 18 to a ground bus 30, which is connected to an outer lead 17 by main ground lead 32. Each signal lead has a first end 20 connected to the pad portion 18 of an outer lead 17, and a second end 21 connected to the ground bus 30. Each ground lead 24 likewise has a first end 24 connected to pad 18 and a second end 27 connected to the ground bus 30. A power bus 36 is situated internally of the ground bus 30 and is connected to an outer lead 17 by the main power lead 38. Decoupling pads 33, 40 are formed integrally with the ground and power buses 30, 36 respectively and serve as mounting points for a decoupling capacitor in the finished chip carrier. The lead frame 10 is manufactured by a standard etching process wherein copper strip is coated with photo resist and exposed to ultraviolet light to cure it where it is desired to leave copper. Remaining (uncured) resist is washed away and the copper in areas left unprotected by cured resist is etched away with acid. The areas unprotected by resist are different on opposite sides of the lead frame 10 so that etching only partially through the copper from one side may be achieved. Where adjacent areas on opposite sides are unprotected, etching through is achieved. Indexing holes 16 are provided in the carrier strip 14 so that exposure and etching may be accomplished in a step wise operation.
FIG. 2 depicts a finished chip carrier 11; the lead frame 10 is bonded to a ceramic substrate 12 by any of the procedures described in U.S. Pat. Nos. 3,744,120 (Burgess et al), 3,766.634 (Babcock et al), 3,854,892 (Burgess et al), 3,911,553 (Burgess et al), 3,994,430 (Cusano et al), and 4,129,243 (Cusano et al).
The processes involve bonding a metallic member to a non-metallic substrate by means of a bonding agent in the form of a eutectic composition at the interface. The preferred materials in the context of the present invention are a copper lead frame and a ceramic substrate of alumina or beryllia, the bonding agent therefor being copper oxide according to the teachings of the above patents. The copper oxide may be formed on the lead frame 10 most conveniently by heating the entire lead frame in a reactive atmosphere containing oxygen, or by applying particulate copper oxide in an appropriate vehicle to one of the interface surfaces. The lead frame is placed in contact with the ceramic and heated to just below the melting point of the copper, which forms a copper-copper oxide eutectic melt at the interface which wets both the lead frame and the substrate. Upon cooling, the melt bonds the copper to the substrate. The amount of eutectic composition is so small that, for thermal and electrical purposes, the bond behaves essentially as if it were metal and ceramic. The outer portions of outer leads 17 (FIG. 1) may be sheared off to leave only pads 18 as shown so that the chip carrier 11 may be plugged into a socket mounted on a circuit board, or the leads 17 (FIG. 1) may be bent under the substrate 12 to form legs which may then be soldered to a circuit board.
FIG. 3 is a perspective of a corner of the ground bus 30 and power bus 36 after the lead frame 10 has been placed against the substrate 12 but prior to bonding. Here neck portions for fusible links 22 at second ends 21 of signal lead 19 are apparent; the links 22 are recessed from the planar surface 13 (FIG. 5) of the lead frame 10 which bonds to the substrate 12 and thus do not bond thereto. A similar neck portion or fusible link 44 connects the power bus 36 and chip support pad 42. Where the oxide has been formed on the entire lead frame, the fusible links 22, 44 melt during bonding of the lead frame 10 due to the higher ratio of copper oxide to copper in the cross section of the fusible links.
Where the oxide is only present at the contact interface between the lead frame and the substrate, as in the case where particulate is deposited on the substrate, the fusible links 22 remain pure copper and thus will not melt during the bonding of the lead frame 10 to the substrate 12. Links may then be individually fused by placing electrodes on either side thereof and passing sufficient current therethrough to melt the link 22 in the manner of a fuse. This procedure is not as simple as mass fusing oxide-coated links 22 by heating, but offers the advantage of enabling finer lead geometry. Oxidization of the lead frame causes a slight volume swell of the leads which, in the case of fine clearances, could cause fusing together during the heating process, the fusing being facilitated by the higher oxide to metal ratio in the fine leads and resultant eutectic melt.
Details of other neck portions or fusible links and the melting thereof are depicted in FIGS. 4 through 7. FIG. 4 is a plan view of a portion of the lead frame 10 and substrate 12 in the area where ground bus 30 is connected to power bus 36 by first link or fusible link 22. Note that the ground lead 24 has neck portion or fusible link 26 at first end 25 where the lead 24 attaches to pad 18. While the link 26 is not narrower than the lead 24 in plan view, it is recessed from the substrate 12 in the manner of links 22 and 44 described in conjunction with FIG. 3. All links 22, 26, 34, and 44 are similar in cross section and referred to generally as neck portions. FIG. 5 is a cross section which depicts a portion of the signal lead 19 where it attaches to ground bus 20 via link 22, and also shows the link 34 attaching ground bus 30 to power bus 36.
FIG. 6 is a plan view similar to FIG. 4 after bonding the lead frame 10 to the substrate 12 and fusing links 22, 26, and 34, leaving gaps 23, 27, and 35 as shown, isolating the signal leads 19 from the ground bus 30, isolating the ground bus 30 and ground leads 24 from the pads 18, and further isolating the ground bus 30 from the power bus 36. The ground leads 24 which alternate with signal leads 19 are thus electrically isolated therefrom and provide electromagnetic shielding so that the finished chip carrier will be of a "low cross-talk" design.
FIG. 8 shows a semiconductor chip 46 mounted on the chip mounting pad 42 and wire bonded to the second end 21 of a signal lead 22. Additional wire bond connections (not shown) are made between the ground bus 30 and the chip 46, as well as between the power bus 36 and the chip 46.
While the foregoing description has been directed to a lead frame for a carrier for a single semiconductor chip, it should be apparent to one skilled in the art that the fusible link principle described has broader application. For example, several chips on a single ceramic substrate may be interconnected by a network of leads whose spacing is maintained by fusible links therebetween which melt as the network is bonded to the substrate and thus isolate leads in different sections of the network.
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Copper lead frame for manufacturing a semiconductor chip carrier has signal leads extending from outer leads about the periphery of the frame and temporarily attached to a ground bus toward the center of the frame by fusible links. Ground leads extend from bus alternately with signal leads and have fusible links at outer leads which are melted to isolate them from signal leads and eliminate noise between signal leads in finished carrier. A power bus located within the ground bus and a chip mounting pad located with the power bus are similarly positioned by fusible links.
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This is a division of application Ser. No. 451,296, filed Mar. 14, 1974, now U.S. Pat. No. 3,951,397.
BACKGROUND OF THE INVENTION
The invention relates to a method and apparatus for shade marking a web spread into layers and, more particularly, for marking areas of successive layers with an image indicating their respective layer.
PRIOR ART
In volume production of wearing apparel, web material or fabric is spread on a cutting table in multiple layers which are subsequently cut together into pattern pieces. A bolt or roll of material often varies gradually along its length in its color shade. Areas of the web displaced from one another a substantial distance, in comparison to the length of the cutting table, for example, may have a readily perceptible difference in shade. Customarily, to avoid assembly of multishaded apparel articles, pieces cut from the pile of layers or "spread" are identified according to layers to permit them to be later selected and assembled with pieces of a common layer and therefore of substantially the same shade.
Manual shade marking is usually time-consuming, tedious, and susceptible to error. Prior developments in automating the shade marking process with spreading operations have had limited success. An approach to automating the marking process is disclosed in U.S. Pat. Nos. 2,756,992 and 2,783,993. A problem encountered in the use of the apparatus and method shown in these patents is excessive drag on the spreading machine produced by forces developed in the elements associated with the marking device and its associated drive. This resistance to movement in a manually operated spreading machine causes undesirable operator fatigue and detrimentally increases tension in the goods being spread. Subsequent efforts to power a spreading machine and its associated marking apparatus to avoid problems of excessive tension have substantially increased the complexity of the entire machine and have not been completely satisfactory in operation.
In addition to these difficulties, apparatus disclosed in the above-mentioned patents is limited in its flexibility in marking various pattern layouts. Owing to the fixed relationship between the rotation of the wheels of the spreading machine and the marking cycle of the image producing elements, a change in the longitudinal spacing of the images applied to the web is not readily achieved. Variations in the size and arrangement of pattern pieces in a layout, both along a spread of goods and from one production run or "cut" to another, require a flexibility in marking frequency not achieved in the prior art, to ensure that each pattern piece is identified according to its layer with at least one mark while not applying excessive markings to the goods.
U.S. Pat. Nos. 1,605,991 to Shields and 2,326,459 to Hansen disclose means for printing images on a web, while Pat. Nos. 3,677,536 to Paterson and 2,659,597 to Shaak et al disclose apparatus for controlling slack and for controlling operations in a spreading machine, respectively.
SUMMARY OF THE INVENTION
The invention provides a method and means for automatically shade marking a web as it is discharged from a spreading machine, wherein the speeds and forces of the marking elements are independent of the speed and driving load of the machine. In accordance with the invention, the marking elements are intermittently driven in a stamping action which neither develops nor requires significant tension in the web other than that normally used to pull the web from the spreading machine. The length of a web feed path on the machine is caused to vary during the marking operation to permit the portion of the web at a marking station to stop instantaneously during the marking process, while allowing the machine to move over the work area and discharge the web at a substantially uniform rate.
In a preferred embodiment, the invention is applied to a manually moved spreading machine of otherwise typical construction. The shade marking apparatus of the invention utilizes an independent power supply, conveniently an electrical power source, for its energy requirements to avoid additional manual effort and to provide fast response of the marking apparatus.
In a manner similar to that of a typical manual spreading machine, a web is drawn through a feeding path on the machine as the machine moves away from a clamped end of a layer being spread. In accordance with the invention, the feed path on the machine includes a loop of variable length which, as disclosed, is defined by a movable rod. At a proper time, power operated marking means engages the web against a platen to positively mark the web according to layer. Simultaneously with operation of the marking means, the movable rod is displaced by a power operated actuator to shorten the feed path to release a limited length of web. This action allows a uniform rate of discharge from the machine, and allows the area of the web being marked to stop instantaneously relative to the marking platen for reliable and uniform marking.
An important aspect of the invention is the coordination of the marking apparatus to the particular pattern arrangement to be cut from the spread of web material. By such coordination, positive marking of each pattern piece is ensured, while excessive marking is avoided. This is accomplished by the invention where coordinating means is provided along the work area at lines across the web which intercept a maximum number of pattern pieces. As the spreading machine traverses the work area, means responsive to the coordinating means causes the marking means to be energized and the web to be marked across its width at locations corresponding to the selected intercepting lines.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a spreading machine and associated apparatus embodying principles of the invention.
FIG. 2 is a fragmentary, perspective view of a portion of a cutting table on which a pattern cutting plan and a spread of fabric web are shown.
FIG. 3 is a cross sectional, elevational view of the spreading machine taken along the line 3--3 of FIG. 1.
FIG. 4 is a perspective view of one of several shade marking devices provided on the spreading machine.
FIG. 5 is a perspective, fragmentary view of a control member for advancing images of the several marking devices.
FIG. 6 is a schematic, electrical circuit for energizing various actuators of the marking apparatus.
FIG. 7 is a perspective view of a modification of the preferred apparatus for controlling the marking operation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown a spreading machine 10 of generally conventional construction and adapted to be manually driven over a cutting table 11. The machine 10, carrying a web or fabric supply 12, is caused to reciprocate over the table 11 to pile successive layers 13 of the web in a work area on the table.
The spreading machine 10 comprises a four-wheeled carriage having its body principally formed of a pair of opposed, generally planar, vertical side members 16 and 17 and a plurality of transversely extending bars 18 (FIG. 3) bolted or otherwise secured to the side members. A pair of grooved wheels 20 supporting the adjacent side frame member 16 lie on a longitudinal track 21 at an edge of the table 11. This side 16 of the machine is normally referred to as the front of the machine with regard to the normal walking path of an operator along the track 21. The opposite side 17 of the machine 10 is supported by a corresponding pair of wheels 22 (FIG. 3).
The supply of the web 12 is carried in a station, generally indicated at 23, formed over the transverse bars 18 between the side frames 16 and 17. The web 12 is fed along a path defined by a series of transverse guide rods 26, 27, and 28. The rods 26-28 may preferably be rotatably mounted at their respective ends on the machine 10 to minimize frictionally induced drag and resulting tension in the web 12. As viewed in FIGS. 1 and 3, the leftward or first rod or roller 26 is supported in yoke portions 29 of a pair of uprights 30 of the side frames 16 and 17. Where the goods to be spread are supplied in roll form, the roll may be rotatably mounted on the roller 26 with the web being fed off the roll to the underside of the second roller 27.
The second and third rollers 27 and 28 are mounted on a pair of opposed, horizontally extending brackets 32 bolted to adjacent main uprights 33 of the side frames 16 and 17. After passing over the rightward roller 28, the web 12 is threaded through a pair of drop-off rollers 35 and 36 forming a discharge station, generally indicated at 37, of the machine 10. A web marking station 41 is arranged between the guide rollers 27 and 28 in the area of the main uprights 33.
The marking station 41 includes a platen 42 extending horizontally between the brackets 32. A cross tie or plate 43 extends above the platen 42 between the brackets 32 and supports a plurality of marking devices 44 in a line transverse to the web path over the platen 42. A perspective view of a typical marking device 44 is illustrated in FIG. 4. The device 44 is conveniently provided as a commercial numbering stamp, such as manufactured by The Bates Manufacturing Company, of Orange, New Jersey. The numbering device 44 includes a U-shaped body 46 containing numbering wheels 47 having raised printing characters or digits 48. The printing characters 48 are automatically inked by a pivoted pad (not shown) when the wheels 47 are in the illustrated retracted position. A stem 49, normally fitted with a handle, is fixed to the armature (not shown) of an associated solenoid actuator 51. The stem 49 is slidable into the body 46 against the force of a retraction spring (not shown) to move the wheels 47 relative to the body. The body 46 of each marking device 44 is vertically, slidably supported in an associated slot 53 in a horizontally extending leg 54 of the cross plate 43. When the actuators 51 are energized, the stems 49 of the marking devices 44 are driven downwardly to cause the U-shaped body to engage the web 12 in a perpendicular direction against the platen 42 and the wheel marking or printing surfaces 48 in an imaging movement to transfer an ink image to the web.
A loop forming and control rod 57 is supported at its ends in a set of depending legs 58 of a pair of opposed bell cranks 59. The bell cranks 59 support the rod or roller 57 for pivotal movement on the machine 10 about the horizontal axis defined by pivot pins 60. The bell cranks 59 and loop control rod 57 are biased downwardly to their illustrated positions, forming a major loop length, by a pair of tension springs 61 anchored to the main uprights 33. A pair of solenoid actuators 63 (only one is seen in FIG. 1) mounted on the outside faces of the brackets 32 are adapted to positively retract the control rod 57 to a position indicated in phantom in FIG. 3 corresponding to a minor loop length. The actuators 63 draw a pair of associated tension rods 64 connected to a pair of generally upstanding legs 65 of the bell cranks 59.
The web marking and loop control actuators 51 and 63 are operated by either of two electrical limit switches 66 and 67 carried by the spreading machine immediately above the table 11. The limit switch 66 is secured directly to the front frame member 16, while the limit switch 67 is secured to an extension bracket 68 bolted to the front frame member. FIG. 6 schematically illustrates an electrical circuit showing the connection of the switches 66 and 67 between an electrical power source, such as a utility power line, and the various actuators 51 and 63. The limit switches 66 and 67 and associated pivot arms 65 are arranged to sense the presence of pattern coordinating elements 69 placed at advantageous locations along the path of the machine 10 on a steel strip 71 embedded in the table 11.
The active work area on the table, i.e., the length of a spread, is normally defined by the length of a particular cutting pattern, or multiples of the length of the cutting pattern. A cutting pattern 76, as partially shown in FIG. 2, may be initially positioned on the table 11 to determine the spread length and determine an arrangement of pattern pieces 78 and then removed prior to the actual spreading operation. Before removal of the cutting pattern, in accordance with an important aspect of the invention, the pattern coordinating elements 69, ideally in the form of blocks of permanent magnetic material, are positioned at advantageous points along the work area.
Ideally, the location of the elements 69 is determined by visual inspection of the pattern and the selection of points on the steel strip 71 from which imaginary lines 77, extending transversely across the pattern 76, intercept a maximum number of pattern pieces 78 ordinarily without missing a piece and without unnecessarily crossing any of the pieces with a plurality of lines. The use of magnetic force is particularly suited for holding the elements 69 along the work area, since it allows the elements to be readily repositioned substantially anywhere along the length of the table 11 when a different pattern is to be cut.
In operation, the spreading machine 10 is manually driven over the table 11 alternately from one end of a work area to the other. As the machine 10 reverses direction, a fold is formed and a new layer is initiated. The lead end and subsequent folds between each layer are clamped or otherwise held at their associated ends of the work area by conventional means, not shown.
As the machine 10 moves, the web 12 is drawn from the supply station 23 through the feeding path on the machine. As one or the other switch 66 or 67 is tripped by one of the coordinating elements 69, all of the actuators 51 and 63 are instantaneously energized to mark the web and release the web loop. Feeding movement of the web through the drop-off rollers 35 and 36 is thus maintained at a constant rate without an increase in web tension, while the web portion on the platen 42 is momentarily brought to a stop by a natural braking action of the bodies 46 and marking surfaces 48 as they engage the web in a stamping motion. The sensing arms 65 are pivoted on opposite sides of the switches 66 and 67 in a manner which makes the left-hand switch 66 active and the right-hand switch inactive when the machine 10 is moving to the left and vice versa when the machine is moving to the right. The distance between either of the switches 66 or 67 and the discharge station 37 is arranged to be approximately equal to the length of the web portion between the discharge station 37 and the printing station 41 so that the line of marks produced by the marking devices 44 eventually aligns with the relevant coordinating element 69 causing the marking operation.
The number and spacing between the marking devices 44 are selected by considering the average size and arrangement of the pattern pieces to be cut from material spread by the machine in question. Ordinarily, the marking devices 44 are arranged to simultaneously produce identical images. Where each layer in the pile 13 is to be marked with a separate image, e.g., a consecutive number, a marking device control 81 (FIGS. 3 and 5) is operated at the end of each pass of the machine 10. The control 81 is shifted transversely in a slot 82 on the cross bar 33 by manually engaging a knob 85. A pair of cam blocks 83 on the control 81 associated with each marking device 44 operate a shifting lever 84 (FIG. 4) to cause the numbering wheels 47 to shift one digit upon actuation of one of the switches 66 and 67.
An alternative arrangement for controlling the actuators 51 and 63 is illustrated in FIG. 7. In this embodiment, the mentioned switches 66 and 67 are replaced by a switch 87 and the pattern coordinating means 69 are replaced by a cam 88 fitted to one of the wheels 22. Rotation of the wheel 22 and corresponding angular displacement of the cam 88 cause the switch 87 to be closed and the actuators 51 and 63 to be energized periodically with each revolution of the wheel. The resulting mark applied by the devices 44 will appear on transverse lines across the web 12 longitudinally spaced from each other a distance equal to the circumference of the wheel 22. Where other spacings are desired, multiple cams or a fixed ratio rotary drive between the wheel and cam may be provided. The embodiment of FIG. 7 may be employed where it is not necessary to minimize the number of marks, or where it is not necessary to ensure that all of the pattern pieces be marked.
Although preferred embodiments of the invention have been illustrated and discussed, it is understood that various modifications and rearrangements may be resorted to without departing from the scope of the invention. It is contemplated, for example, that various elements and functions of either the marking station or the loop control apparatus may be embodied as an attachment for existing web spreading machines.
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A method and means for shade marking a fabric web as it is machine spread on a cutting table wherein identifying marks are applied by intermittent stamping action while uniform web discharge speed and tension are maintained by a variable length web feeding path on the machine. Stamping of the web and variation of the feed path length are accomplished by power actuator means controlled by means responsive to pattern coordinating means arranged along a work area on the cutting table to ensure marking of the areas of substantially all of the pattern pieces to be cut without unnecessary multiple marking of such pieces.
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BACKGROUND OF THE INVENTION
(1) Field of the Invention
The present invention relates generally to an input circuitry of a fork lift truck control system using a microcomputer, and more particularly to a circuit for detecting and signalling to the microcomputer through a common bus the height of a fork mounted on an upright above its lowest position based on the length of a chain passed through a chain wheel attached on the top end of an inner mast of the upright.
(2) Description of the Prior Art
A fork lift truck comprises, in general, a load lifting mechanism and vehicle body. The load lifting mechanism comprises a vertically elongated guide rail called an "upright" and a fork slidable along the upright.
The load lifting mechanism further comprises: (a) a tilt cylinder attached to a front portion of the vehicle body having a piston interlinked with an outer mast constituting the upright rotatably supported by the front portion of the vehicle body, so that a tilting angle of the upright with its vertical position with respect to the ground as a neutral position can be adjusted; (b) a lift cylinder attached along the elongated direction of the outer mast having a piston interlinked with an inner mast constituting the upright upwardly extendable from the outer mast; (c) a chain wheel rotatably attached to the top end of the piston of the lift cylinder and engaged with a chain, one end of the chain attached to the outer mast or lift cylinder body and the other end of the chain attached to either a lifting member fitted into the inner mast so as to move upward and downward together with the inner mast and fork or to the fork engaged with the lifting member, so that the movement of the lift cylinder causes the inner mast to elevate upward and accordingly causes the fork to move upward along the outer mast by means of the chain engaged with the chain wheel, thereby lifting a load piled thereon.
A microcomputer system has been proposed which performs an automatic lifting operation for the fork and tilting angle control of the upright. An input unit of the microcomputer system comprises a plurality of sensors to be described hereinbelow and microcomputer input interface circuit connected to the sensors. One of the sensors includes a first sensor provided for detecting the height of the fork lifted upward from its lowest position. The first sensor comprises a disc having a plurality of slits along the radial direction thereof and a photocoupler provided across the disc so that the disc can rotate together with the chain wheel through the photocoupler. It will be noted that the disc is attached coaxially to the chain wheel. The photocoupler comprises a light emitting member, e.g., LED (light emitting diode) which emits light toward the disc and a light receiving member, e.g., photo transistor which receives the light passed through the slits provided through the disc and converts the received light into an electrical signal. If the number of the pulse-shaped signals electrically converted on a basis of the light passed through the slits of the disc is counted by means of a counter, the microcomputer can determine the height of the fork lifted from the lowest position. Other sensors include a second sensor for detecting a tilting angle of the upright and third sensor for detecting the presence of load on the fork. The second sensor comprises a potentiometer, located adjacent to the tilt cylinder, across which a DC voltage is applied. The potentiometer is provided with an operation lever and pin attached to the top end of the operation lever, the pin inserted into an elongated hole provided at an oblique angle within a fixed member attached around the outer surface of the piston of the tilt cylinder, so that the operation lever rotates clockwise or counterclockwise as the piston of the tilt cylinder pushes or pulls the outer mast to adjust the tilting angle of the upright. Consequently, the potentiometer sends a variable voltage signal to the input interface circuit of the microcomputer system.
The input interface circuit for the second sensor comprises an analog-to-digital converter. The analog-to-digital converter used in this fork lift truck control device comprises nine resistors, five variable resistors, and five comparators. That is to say, all noninverting input terminals of the five comparators are connected to the potentiometer, i.e., second sensor via a resitor and each inverting input terminal of the five comparators is connected to one of a plurality reference voltage sources formed with a DC voltage supply, resistors, and variable resistors for parallel comparison of the received analog voltage from the potentiometer with each reference voltage corresponding to a value of the tilting angle of the upright. Therefore, a first comparator has a first reference voltage at its inverting input terminal, a second comparator has a second reference voltage at its inverting input terminal, a third comparator has a third reference voltage at its inverting input terminal, a fourth comparator has a fourth reference voltage at its inverting input terminal, and a fifth comparator has a fifth reference voltage at its inverting input terminal. All comparators are previously adjusted to provide a logical "0" level signal when zero voltage or voltage below respective reference voltages is applied to the noninverting input terminals of the comparators. The first reference voltage corresponds to a zero degree (neutral position) tilting angle of the upright, the second reference voltage corresponds to one degree of the backward tilting angle of the upright, the third reference voltage corresponds to three degrees of the backward tilting angle of the upright, the fourth reference voltage corresponds to four degrees of the backward tilting angle of the upright, and the fifth reference voltage corresponds to twelve degrees of the backward tilting angle of the upright.
Therefore, e.g., when the backward tilting angle of the upright is between zero degree and one degree, the output bit string of the analog-to-digital converter indicates 00001 and when the backward tilting angle of the upright is more than twelve degrees, the output bit string of the analog-to-digital converter indicates 11111. It will be noted that the analog-to-digital converter of the type described above is not provided with an encoder circuit for weighing each bit signal since each meaning of the output bit strings is previously identified by the microcomputer main frame.
The third sensor is provided for detecting the weight of load applied on the fork for changing a target value of the tilting angle of the upright so as to place the fork in a horizontal position with respect to the truck body due to the bending of the upright and fork which vary depending on the weight of load, e.g., by measuring a hydraulic pressure within the lift cylinder or by measuring both hydraulic pressure and pneumatic pressure of a front wheel of the vehicle body. When a drive signal indicating that a load is piled on the fork is sent from the third sensor into a switch constituting the input interface circuit to drive the switch to close, the switch is closed to send a "1" signal into the microcomputer main frame. When no drive signal is sent from the third sensor into the switch, the switch remains off so that the microcomputer receives a "0" signal from the switch and judges that no load is piled on the fork.
On the other hand, when the potentiometer output voltage exceeds the first reference voltage, the first comparator only sends a "1" bit signal via a first signal line D A of five parallel signal lines D A through D E within the common bus into the microcomputer main frame to indicate that the upright is tilted more than zero degree (0°) backward (toward the truck body) with respect to the upright position vertically disposed to the ground. Similarly, when the output voltage of the potentiometer exceeds the second reference voltage, the first and second comparators send a 37 1" bit signal through the first and second signal lines into the microcomputer main frame to indicate that the angle of the upright is more than one degree (1°). Consequently, when the output voltage of the potentiometer exceeds the fifth reference voltage, all comparators send "1" bit signals through the signal lines into the microcomputer main frame to indicate that the angle of the upright is tilted backward more than twelve degrees (12°).
Hence, the microcomputer judges from the "0" level signal received from the switch that no load is applied on the fork and performs a feedback control over the tilt cylinder so that the upright tilts backward to an angle within unloaded neutral range {zero degree (0°) through one degree (1°) or, the bit string of the A/D converter indicates 00001}. That is, an operational command is given to a sevomotor circuit connected to the microcomputer main frame to actuate a hydraulic pressure control valve so that the tilt cylinder is operated to tilt the upright at the target value described hereinabove. On the other hand, the microcomputer judges from the "1" level signal received from the switch that a load is applied on the fork and performs the feedback control over the tilt cylinder so that the upright tilts backward at an angle within loaded neutral range (3° through 4°, i.e., the bit string of the A/D converter indicates 00111).
There is, however, a drawback in the input interface circuit of the microcomputer, i.e., a counting circuit for informing the microcomputer main frame of the lifting height of the fork on a basis of the output signal from the first sensor and the analog-to-digital converter for outputting a bit string corresponding to the upright tilting angle. In more detail, in the case of the lifting height counter, since the pulse-shaped signal from the photocoupler, i.e., first sensor is compared directly with a reference voltage subsequently to a waveform shaper so that a rectangular wave is formed and sent into an up/down counter, the amplitude of the pulse-shaped signal generated from the photocoupler is not sufficiently large and stable to enable direct comparison with the reference voltage. In addition, such counting circuit cannot follow the repeated upward and downward movements of the fork within a short distance. Consequently, it is difficult for the UP/DOWN counter to count correctly the number of rectangular pulses produced on a basis of the output signal of the photocoupler.
SUMMARY OF THE INVENTION
With the above-described drawbacks in mind, it is an object of the present invention to provide a fork lift truck control system using a microcomputer as a main control unit wherein an input interface circuit for the first and sensor is improved for always providing correct data of the lifting height of the fork for the microcomputer.
This can be achieved by providing two photocouplers, i.e., light emitting members and light receiving members as the first sensor within the sensing unit of the fork lift truck control system, two output pulsed-shaped signals from the two photocouplers having a phase difference of 90° from each other when the fork is lifted, and accordingly a new lifting height counting circuit in the input interface circuit of the microcomputer which includes an UP/DOWN counter which counts the number of rectangular pulses on the rising or falling edge of each rectangular wave formed by shaping each of the two output signals from the photocouplers.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will be appreciated from the following description taken in conjunction with the accompanying drawings in which like reference numerals designate corresponding elements, and in which:
FIG. 1 shows a side view of a fork lift truck;
FIG. 2 shows a side view of a first sensor attached to a chain wheel shown in FIG. 1;
FIGS. 3(A) and 3(B) show an overall circuit diagram of a fork lift control system;
FIG. 4 shows an arrangement of a second sensor attached adjacent to a tilt cylinder;
FIG. 5 shows an internal circuit configuration of an analog-to-digital converter shown in FIG. 3(A) which converts an analog voltage signal from the second sensor into a predetermined five-bit string to indicate a backward tilting angle of an upright with respect to the upright position vertically disposed to the ground;
FIG. 6 shows a relationship of an output bit "1" signal from the analog-to-digital converter with respect to an upright tilting angle;
FIG. 7 shows a rectangular waveform to be counted by a conventional lifting height counting circuit;
FIGS. 8(A) and 8(B) show a preferred embodiment of a lifting height counting circuit of the input interface circuit of a microcomputer according to the present invention;
FIG. 8(C) shows an alternative of the peripheral input circuit of an UP/DOWN counter shown in FIG. 8(B); and
FIGS. 9(A) and 9(B) show a chart of output waveform timing of each internal circuit block in the lifting height counting circuit shown in FIGS. 8(A) and 8(B) according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will be made hereinafter to the attached drawings and first to FIG. 1 which illustrates a fork lift truck.
In FIG. 1, numeral 1 denotes a truck body, numeral 2 denotes an upright comprising an outer mast 2a and an inner mast 2b supported by the outer mast 2a so as to move upward and downward. A lower end of the outer mast 2a is mounted on a front portion of the truck body 1 so as to provide a rotatable support of the outer mast 2a. Numeral 3 denotes a tilt cylinder, one end thereof fixed on the truck body 1 and the other end thereof having a piston 3a attached to the outer mast 2a so that the upright 2 is adjustably tilted in the forward or rearward direction. Numeral 4 denotes a lift cylinder, one end thereof fixed on the outer mast 2a and the other end thereof having a piston 4a engaged with the inner mast 2b. Numeral 5 denotes a chain wheel rotatably mounted on the upper end of the piston 4a. An intermediate portion of a chain 6 is engaged with the chain wheel 5, one end of the chain 6 attached to the outer mast 2a or lift cylinder 4, and the other end thereof mounted on a lifting member (not shown) fitted into the inner mast 2b or a fork 7 supported by the lifting member to permit upward and downward movement of the fork 7 along the outer mast 2a. Accordingly, when the lift cylinder 4 is actuated, the inner mast 2b moves upward. As the inner mast 2b moves upward, the fork 7 pulled by the chain 6 moves upward together with the inner mast 2b, so that a load carriage mounted on the fork 7 can be lifted upward.
On the other hand, in FIG. 2, numeral 8 denotes a first sensor for detecting a lifting height of the fork 7 from the lowest position comprising a disc 8a having a plurality of slits penetrated radially therethrough and an optical device, i.e., photocoupler 8b having a couple of light emitting and light receiving members, e.g., light emitting diode and photo transistor. The disc 8a is coaxially attached to the chain wheel 5 so as to rotate at a speed equal to that of the chain wheel 5. When the disc 8a rotates, a light emitted from the light emitting member is passed through one of the slits of the disc 8a so that a pulse-shaped electrical signal is produced having a number of pulses corresponding to the total length of the chain 6 passed through the chain wheel 5. Therefore, the microcomputer receives the counted value from the UP/DOWN counter and calculates the fork lifting height.
FIGS. 3(A) and 3(B) illustrate a circuit block diagram of a fork lift control system mounted in the fork lift truck shown in FIG. 1. In FIGS. 3(A) and 3(B), symbol A denotes a sensing unit including the first sensor, second sensor, and third sensor. The first sensor is described hereinbefore with reference to FIG. 2 as the photocoupler 8a and disc 8b. The second sensor is described hereinafter with reference to FIG. 4 and the third sensor is also described hereinafter.
Symbol B denotes a control unit comprising an input interface circuit B 0 , main frame of a microcomputer B 1 , and output control circuit B 2 , each connected via a common bus. The microcomputer main frame B 1 comprises a Central Processing Unit (CPU), Random Access Memory (RAM), and Read Only Memory (ROM) in which predetermined values of the lifting height of the fork 7, tilting angle of the upright 2, load and other data are stored and in which the lifting height of the fork 7 is indicated on a basis of the currently counted value of the lifting height counting circuit in the input interface circuit Bo and the lifting height value is stored in the RAM so that the fork 7 can lift upward or downward to arrive at a target value and furthermore a key board through which an operator can set desired values of these variables. The microcomputer main frame B 1 produces various control command signals based on the output signal from the sensing unit A and data in connection with lifting height, tilting angle, or load piled on the fork 7 stored in the ROM. The output control circuit B 2 comprises a first output control circuit B 2a provided for controlling a lifting height of the fork 7 through the lifting cylinder 4 and a second output control circuit B 2b provided for controlling a tilting angle of the upright 2 through the tilt cylinder 3.
Symbol C denotes a driving unit comprising an electric/hydraulic pressure converter C 1 and hydraulic pressure driving unit C 2 . The electric/hydraulic pressure converter C 1 comprises a first and second actuators C 1a and C 1b responsive to an output signal of the first and second output control circuits B 2a and B 2b , respectively. The hydraulic pressure driving unit C 2 comprises a first and second hydraulic pressure control valves C 2a and C 2b responsive to respective actuation signals from the first and second actuators C 1a and C 1b , respectively. The first control valve C 2a is linked with the lift cylinder 4 for controlling a lifting height of the fork 7 while the second control valve C 2b is linked with the tilt cylinder 3 for controlling a tilting angle of the upright 2 shown in FIG. 1. A pump P is provided between the first and second control valves C 2a and C 2b in the hydraulic pressure driving unit C 2 for supplying a suitable fluid pressure for these control valves. The above-described first output control circuit B 2a , first actuator C 1a , and first hydraulic pressure control valve C 2a constitute a servo control circuit for the lifting height control system. Similarly, the above-described second output control circuit B 2b , second actuator C 1b , and second hydraulic pressure control valve C 2b constitute another servo control circuit for the tilting angle control system.
Next, in FIG. 4, the second sensor in the sensing unit A comprises a potentiometer 12 across which a DC voltage +E 1 is applied. As seen from FIG. 5, an operational lever 12a is attached to the potentiometer 12 for varying the resistance of the potentiometer body 12 according to the rotation angle of the operational lever 12a. The operational lever 12a is provided with a pin 12b at the end thereof, the pin 12b movably inserted into an elongated hole 13a of a plate 13 attached around an outer surface of the piston 3a of the tilt cylinder 3. Therefore, as the piston 3a of the tilt cylinder 3 moves, the pin 12b and operational lever 12a move along an oblique direction of the elongated hole 13a. Consequently, the potentiometer 12 produces an analog voltage signal whose voltage level changes according to an angle of the upright 2 tilted with respect to the position of the upright 2 vertically disposed to the ground. The input interface circuit B 0 includes an analog-to-digital converter 14 shown by FIG. 3(A) which serves to convert the analog voltage signal from the second sensor, i.e., potentiometer 12 into a digital signal, i.e., five-bit string to be fed into the microcomputer main frame B 1 . The internal circuit configuration of the analog-to-digital converter 14 is shown in FIG. 5.
In FIG. 5, the analog-to-digital converter 14 comprises five comparators CP 1 through CP 5 , nine resistors R 1 through R 9 , and five variable resistors VR 1 through VR 5 . A DC voltage is applied between positive terminal +E 1 and ground terminal for producing five reference voltage sources. An input terminal I 1 is connected via a first resistor R 1 to each noninverting input terminal of the comparators CP 1 through CP 5 . An inverting input terminal of the first comparator CP 1 is connected via a second resistor R 2 to the DC voltage supply +E 1 and via a first variable resistor VR 1 to the ground, so that a first reference voltage V 1 is provided at the inverting input terminal thereof. An inverting input terminal of the second comparator CP 2 is connected via a third resistor R 3 to the DC voltage supply +E 1 and via a second variable resistor VR 2 to the ground, so that a second reference voltage V 2 is provided at the inverting input terminal thereof. An inverting input terminal of the third comparator CP 3 is connected via a fourth resistor R 4 to the DC voltage supply +E 1 and via a fifth resistor R 5 and third variable resistor VR 3 to the ground, so that a third reference voltage V 3 is provided at the inverting input terminal thereof. An inverting input terminal of the fourth comparator CP 4 is connected via a sixth resistor R 6 to the DC voltage supply +E 1 and via a seventh resistor R 7 and fourth variable resistor VR 4 to the ground, so that a fourth reference voltage V 4 is provided at the inverting input terminal thereof. An inverting input terminal of the fifth comparator CP 5 is connected via an eighth resistor R 8 and fifth variable resistor VR 5 to the DC voltage supply +E 1 and via a ninth resistor R 9 to the ground. Symbols D A through D E denote output signal lines of the analog-to-digital converter 14, D A denoting a first signal line of the first comparator CP 1 , D B denoting a second signal line of the second comparator CP 2 , D C denoting a third signal line of the third comparator CP 3 , D D denoting a fourth signal line of the fourth comparator CP 4 , and D E denoting a fifth signal line of the fifth comparator CP 5 .
The output voltage of the potentiometer 12 is applied to the analog-to-digital converter 14 via the input terminal I 1 . When the output voltage of the potentiometer 12 is zero or does not exceed the first reference voltage V 1 , all signal lines D A through D E indicate such a bit string as "00000". When the output voltage of the potentiometer 12 exceeds the first reference voltage V 1 , the first comparator CP 1 outputs a high level voltage signal corresponding to a logical "1" signal, the bit "1" signal at the first signal line D A indicating that a backward tilting angle of the upright 2 is more than zero degree as shown in FIG. 6. When the output voltage of the potentiometer 12 exceeds the second reference voltage V 2 , the second comparator CP 2 also outputs a high level voltage signal corresponding to a logical "1" signal, the bit "1" signal of the second signal line D B indicating that a backward tilting angle of the upright 2 is more than one degree. When the output voltage of the potentiometer 12 exceeds the third reference voltage V 3 , the third comparator CP 3 also outputs a high level voltage signal (bit "1") into the third signal line D C thereof the bit "1" of the third signal line D C indicating that the upright 2 is tilted backward more than three degrees. When the output voltage of the potentiometer 12 exceeds the fourth reference voltage V 4 , the fourth comparator CP 4 also outputs a high level signal (bit "1") into the fourth signal line D D thereof, the bit "1" of the fourth signal line D C indicating that the upright 2 is tilted backward more than four degrees. When the output signal of the potentiometer 12 exceeds the fifth reference voltage V 5 , the fifth comparator CP 5 also outputs a high level signal (bit "1") into the fifth signal line D E thereof, the bit "1" of the fifth signal line D E indicating that the backward tilting angle of the upright 2 exceeds twelve degrees (12°). The relationship between a tilted angle of the upright 2 with a vertical position of the upright 2 as a center (neutral position) and output bit signals of the analog-to-digital converter 14 is illustrated in FIG. 6.
Next, a drawback of a conventional lifting height counting circuit is described with reference to FIG. 7. In FIG. 7, if the conventional counting circuit counts the number of pulses fed from the first sensor via the waveform shaper on the rising edge of each pulse, the counter counts as "count up 1" during an interval of time from point A to point B, i.e., along a time axis from point A to point B. The counter counts as "count down 1" during an interval of time from point B to point C since the rising edge of the pulse shown in FIG. 11 is reversed. The counter counts as "count 0" during an interval of time from point C to point B. Therefore, when the fork 7 is lifted or lowered repeatedly within a short distance during an interval of time between point B and point C, the counter counts down only so that the counted value does not agree with the actual lifting height of the fork 7.
FIGS. 8(A) and 8(B) show a preferred embodiment of a lifting height counting circuit incorporated into the input interface circuit according to the present invention. In FIGS. 8(A) and 8(B), symbols R 10 through R 56 denote resistors, symbols VR 6 and VR 8 denote variable resistors, symbols OP 1 through OP 4 denote operational amplifiers, symbols D 1 through D 5 denote diodes, symbols C 1 and C 2 denote capacitors, symbols INV 1 and INV 2 denote inverter circuits, symbols AND 1 through AND 5 denote AND gate circuits, and numeral 20 denotes an UP/DOWN counter provided for counting and informing the lifting height of the fork 7 to the microcomputer main frame B 1 .
In this preferred embodiment, the first sensor comprises two photocouplers, i.e., detection phases A and B as shown by FIG. 8(A). It will be noted that, in this preferred embodiment, the detection phase A is located across the disc 8a shown in FIG. 2 with its position lower than the detection phase B with respect to the direction toward which the fork 7 is lowered. The construction and operation of the lifting height counting circuit according to the present invention are described hereinafter first with reference to FIGS. 8(A), 8(B), and 9(A).
The detection phase A sends an electrical signal produced from a light passed through the rotating disc 8a as shown by PHASE A of FIG. 9(A) to a first noninvertingtype amplifier to adjust a voltage level of the electrical signal. The first amplifier comprises a first operational amplifier OP 1 whose noninverting input terminal is connected to the detector phase A and ground terminal via the variable resistor VR 6 and resistor R 20 and whose inverting input terminal is connected to plus power supply line +E via the resistors R 12 and R 10 and to the output terminal thereof via the resistor R 14 .
The output voltage signal amplified by the first amplifier is sent into a first waveform shaper so that a rectangular waveform shown by (S) of FIG. 9(A) is produced having equal phase and frequency to the electrical signal of the detection phase A. The first waveform shaper comprises a second operational amplifer OP 2 whose noninverting input terminal is connected to the output terminal of the first operational amplifier OP 1 via the resistor R 16 and to the output terminal thereof via the resistor R 18 and whose inverting input terminal is connected to the plus power supply line +E via the resistor R 10 . The waveform shaper is thus formed of a schmidt circuit. During the high level of the rectangular wave signal shown by (S) of FIG. 9(A), a second transistor Tr 2 turns on. A base of the second transistor Tr 2 is connected to the output terminal of the second operational amplifier OP 2 via a fourth diode D 4 and resistor R 34 and to the ground line via the resistor R 36 . During the low level of the rectangular-wave signal shown by (S), the second transistor Tr 2 turns off and simultaneously a first transistor Tr 1 in turn turns on. A base of the first transistor Tr 1 is connected to the output terminal of the second operational amplifier OP 2 via a second diode D 2 and resistor R 32 , an emitter thereof is connected directly to the plus power supply line +E, and a collector thereof is connected to the ground line via resistor R 42 . When the first transistor Tr 1 turns on, a voltage at point (X) rises sharply and decreases gradually as shown by (X) of FIG. 9(A). A second capacitor C 2 and sixth diode D 6 are connected across the resistor R 42 and resistor R 54 is connected across the sixth diode D 6 to form a differentiator. A point between the second capacitor C 2 and sixth diode D 6 (or resistor R 54 ) is connected to a first AND gate circuit AND 1 and a fourth AND gate circuit AND 4 via a resistor R 52 .
On the other hand, an electrical signal produced by the detection phase B is fed into a second noninverting amplifier, having a phase lag of 90° from the detection phase A as shown by PHASE B in FIG. 9(A). The second amplifier comprises a third operational amplifier OP 3 whose noninverting input terminal is connected to the detection phase B and to the ground line via a variable resistor VR 8 and resistor R 22 and whose inverting input terminal is connected to the plus power supply line +E via resistor R 24 and resistor R 10 and to the output terminal thereof via resistor R 56 . The amplified signal from the second amplifier is then fed into a second waveform shaper to form another rectangular wave shown by (T) of FIG. 9(A). The construction of the second waveform shaper is exactly the same as that of the first waveform shaper. Therefore, the rectangular wave from the second waveform shaper is outputted with a phase lag of 90° with respect to that outputted from the first waveform shaper, as shown by (S) and (T) of FIG. 9(A). The output voltage signal of the second waveform shaper is thereafter fed into a base of a third transistor Tr 3 via a fifth diode D 5 and resistor R 46 . The base of the third transistor Tr 3 is also connected to the ground line via resistor R 48 , an emitter thereof is connected directly to the ground line, and a collector thereof is connected to the plus power supply line +E via resistor R 50 . When the rectangular wave output signal goes high, the fifth diode D 5 conducts and third transistor Tr 3 turns on so that an input voltage Z of a second inverter INV 2 turns to a "0" and output voltage Z thereof turns to a "1". The input terminal (Z) of the second inverter INV 2 is connected to the collector of the third transistor Tr 3 and to input terminals of both the first AND gate circuit AND 1 and third AND gate circuit AND 3. The output terminal (Z) of the second inverter INV 2 is connected to input terminals of both the second and fourth AND gate circuits AND 2 and AND 4 as shown in FIG. 8(B). As shown in FIG. 8(B), the output terminal (Y) of the first inverter INV 1 is connected to input terminals of both the second and third AND gate circuits AND 2 and AND 3. The output terminals of both the first and second AND gate circuits AND 1 and AND 2 are connected to a first NOR gate circuit NOR 1. The outpout terminals of both the third and fourth AND gate circuits AND 3 and AND 4 are connected to a second NOR gate circuit NOR 2. The output pulse signal Y produced through the first inverter INV 1 shown by Y of FIG. 9(A) is ANDed with the input rectangular wave signal Z of the second inverter INV 2 at the third AND gate circuit AND 3. Therefore, the output signal of the third AND gate circuit AND 3 is formed as shown by AND 3 of FIG. 9(A). On the other hand, the output differentiated signal X is ANDed with the output pulse signal Z shown by (Z) of FIG. 9(A) of the second inverter INV 2 at the fourth AND gate circuit AND 4. The output signal of the fourth AND gate circuit AND 4 is formed as shown by AND 4 of FIG. 9(A). Consequently, the output signal of the second NOR gate circuit NOR 2 is formed as shown by W of FIG. 9(A).
In this case, the output signal of the first AND gate circuit AND 1 is always turned to a "0" since there is no logical coincidence between the differentiated signal X and input signal Z of the second inverter INV 2 as shown by X and Z of FIG. 9(A). Furthermore, the output signal of the second AND gate circuit AND 2 is always turned to a "0" since there is no coincidence between the output signal Y of the first inverter INV 1 and output signal Z of the second inverter INV 2. Consequently, the output signal V of the first NOR gate NOR 1 is always turned to a "1". The output signal W of the second NOR gate circuit NOR 2 shown by W of FIG. 9(A) is fed into DOWN terminal of the UP/DOWN binary counter 20 to count decrementally the number of pulses received at the clock terminal C p thereof whenever one of the pulses falls. The clock pulse to be fed into the UP/DOWN counter 20 may be either the output signal V or W fed through the fifth AND gate circuit AND 5 or a clock pulse fed from an external clock generator. In the latter case, the width of the clock pulse needs to be substantially equal to that of either of output negative going pulse signals V and W described above.
Next, hereinafter described with reference to FIGS. 8(A), 8(B), and 9(B), is the case when the rotational direction of the chain wheel 5 is reversed so that the fork 7 shown in FIG. 1 is lifted upward.
In this case, the phase of the electrical signal from the detection phase B is advanced 90° from that of the other electrical signal from the detection phase A, as shown by PHASE A and PHASE B of FIG. 9(B). The output signal of the first AND gate circuit AND 1 is formed as shown by AND 1 of FIG. 9(B) since there is a logical coincidence between the differentiated signal X and input rectangular wave signal Z of the second inverter INV 2. The output signal of the second AND gate circuit AND 2 is formed as shown by AND 2 of FIG. 9(B) since there is a logical coincidence between the output signal Z of the second inverter INV 2 and the output signal Y of the first inverter INV 1. Therefore, the output signal V of the first NOR gate circuit NOR 1 is formed as shown by V of FIG. 9(B) and sent into the UP terminal of the UP/DOWN counter 20 and into the clock terminal C p thereof via a fifth AND gate circuit AND 5, so that the counter 20 counts incrementally the number of pulses fed into the clock terminal C p whenever one of the pulses falls. In this case, both output signals of the third and fourth AND gate circuits AND 3 and AND 4 are always turned to "0"s and therefore the output signal of the fifth AND gate circuit AND 5 is only that fed from the first NOR gate circuit NOR 1. The UP/DOWN counter 20 is reset to zero by a reset pulse signal fed from the microcomputer main frame B 1 via the common bus when the fork 7 is placed at its lowest position.
FIG. 8(C) illustrates an alternative of the circuit around the UP/DOWN counter 20 shown in FIG. 8(B), wherein a first OR gate circuit OR 1 is connected to the first and second AND gate circuits AND 1 and AND 2 a second OR gate circuit OR 2 is connected to the third and fourth AND gate circuits AND 3 and AND 4 and a third OR gate circuit is connected to the first and second OR gate circuit OR 1 and OR 2. Therefore, each logical level of the output signals from the first, second, and third OR gate circuits OR 1, OR 2, and OR 3 is reversed as compared with V and W shown in FIG. 9(A) and FIG. 9(B).
Since the construction and operation of the lifting height counting circuit according to the present invention are different from the conventional lifting height counter as described hereinabove, there is no difference between the counted value and actual lifting height of the fork 7. For example, in FIG. 9(A) the UP/DOWN counter 20 counts decrementally as "count down 3" during the time interval from point A to point B, i.e., along the time axis from points A to B and in FIG. 9(B) the UP/DOWN counter 20 counts incrementally as "count up 3" during the time interval from point A to point B. Furthermore, in FIG. 9(A) the UP/DOWN counter 20 counts decrementally as "count down 1" during the subsequent time interval from point B and point C and in FIG. 9(B) the UP/DOWN counter 20 counts incrementally as "count up 1" during the subsequent time intervals from point B to point C. These time intervals between points A, B, and C are the same as those shown in FIG. 7.
In this way, according to the present invention there is provided in the input interface circuit of the microcomputer constituting the fork lift truck control system an improved lifting height counting circuit for detecting the lifting height of the fork from the total movement distance of the chain linked with the fork passed through the chain wheel, whereby the fork lift truck control system can perform more accurate automatic control of the lifting operation of the fork.
It will be understood by those skilled in the art that the foregoing description is in terms of preferred embodiments of the present invention wherein various changes and modifications may be made without departing from the spirit and scope of the present invention, which is to be defined by the appended claims.
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An improved fork lift truck control system using a microcomputer, which comprises a sensing unit including a first sensor for detecting a lift height of a fork above its lowest position and a second sensor for detecting a tilting angle of an upright with respect to a neutral position of the upright including an input interface circuit for interfacing the sensing unit and control unit which has: (a) a lifting height counting circuit which counts the number of pulses produced on a basis of two photo-converted electrical signals fed from two photocouplers constituting the first sensor, the signals having a phase difference of 90° from each other, so that an accurate measurement of the lifting height of the fork can be made; (b) an analog-to-digital converter which produces a bit string according to an output signal from the second sensor; and (c) an abnormal detection facility which detects a defective analog-to-digital converter and second sensor by comparing the bit string presently outputted from the analog-to-digital converter with each of predetermined bit strings that would be produced if the analog-to-digital converter operates normally.
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BACKGROUND OF THE INVENTION
[0001] This invention relates to children's toy water guns of the type modeled after a carbine and having a large water reservoir. More specifically, the invention teaches how to provide such a water gun with the capability to squirt water from a plurality of barrels which reciprocate in out of phase synchronization as water is ejected through them, and to emit sounds associated with the firing of a weapon.
[0002] It is known to make water guns having an electrical pump and an electrical noisemaker. In such water guns the trigger is connected to the actuator of an electrical switch in series with a battery and an electric pump. A noisemaker may also be connected to the battery through the switch. Pulling the switch closes a circuit between the battery and pump thereby causing the pump to continuously force water from a reservoir. Such electric water guns are relatively expensive to manufacture, and short lived when subjected to handling by children in their play environments due to the fragility of the electric pumps. Moreover, such pumps draw relatively large currents from the batteries which must be frequently replaced at further expense.
[0003] It is also known in the art to make water guns having a mechanical pump with a plunger in the shaper of the gun trigger. Pulling the trigger forces the plunger into a chamber thereby forcing air into a reservoir filled with water. With each stroke of the trigger, a volume of water is displaced from the reservoir through a nozzle. Such water guns are generally silent and have no moving parts other than the trigger which is actuated by finger pressure and a return spring which restores the trigger to its rest position after each pull. Although inherently more reliable and less expensive than electrically operated water guns, manual water guns of this type are unable to provide children with the thrill of hearing weapon sounds as the water is “fired” from the gun, or to squirt long duration, continuous streams, of water.
SUMMARY OF THE INVENTION
[0004] The present invention overcomes the aforementioned shortcomings of prior art water guns in teaching how to make a mechanically actuated water gun which can be operated to expel long duration continuous streams of water without any requirement for an electrical power supply, yet which can also emit gun-like sounds, and causing the barrels of the gun to reciprocate, when the trigger is pulled via motor driven slider-crank mechanism connected to the barrels, and an electronic sound system, both of which are connected to a switch actuated by the trigger.
[0005] It is therefore an object of the invention to provide a water gun which can squirt water from a plurality of reciprocating barrels while emitting sounds associated with the firing of a weapon.
[0006] Another object of the invention is to provide a water gun which can continuously emit pressurized water from a reservoir while operating an electrical sound generator.
[0007] Still another object of the invention is to provide a water gun with a trigger having the feel of a conventional water gun trigger and the ability to emit sounds similar to those of a more expensive electrical pump operated water gun.
[0008] A further object of the invention is to provide a water gun with barrels that reciprocate as water is manually pumped through nozzles in the barrels.
[0009] Other and further objects of the invention will be apparent from the following drawings and description of a preferred embodiment of the invention in which like reference numerals are used to indicate like parts in the various views.
DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is an exterior side elevation view of an assembled toy water gun in accordance with the preferred embodiment of the invention.
[0011] [0011]FIG. 2 is an interior side elevation view of the toy water gun of FIG. 1 in a disassembled condition with trigger removed.
[0012] [0012]FIG. 3 is a an enlarged fragmentary view showing a portion of the toy water gun as shown in FIG. 2.
[0013] [0013]FIG. 4A is a fragmentary plan view showing the barrel assembly of the toy water gun of FIG. 1 in a first disposition in use.
[0014] [0014]FIG. 4B is a fragmentary plan view showing the barrel assembly of the toy water gun shown in FIG. 4A in a second disposition in use.
[0015] [0015]FIG. 4C is a fragmentary plan view showing the barrel assembly of the toy water gun shown in FIG. 4A in a third disposition in use.
[0016] [0016]FIG. 5A is a fragmentary plan view showing the trigger assembly of the toy water gun of FIG. 1 in a first disposition in use.
[0017] [0017]FIG. 5B is a fragmentary plan view showing the trigger assembly of the toy water gun shown in FIG. 5A in a second disposition in use.
[0018] [0018]FIG. 6 is a fragmentary view showing an opposite side of a portion of the toy water gun as shown in FIG. 2.
[0019] [0019]FIG. 7 is a schematic view showing an electric circuit for operating the toy water gun in accordance with the preferred embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Referring now to FIG. 1 of the drawings, there is shown a water gun 1 having a housing 3 molded from plastic in the general shape of a futuristic carbine. A grip 5 extends downwardly from the main body 7 of the housing 3 . The grip 5 has horizontally running, vertically spaced, ridges 9 and grooves 11 at its sides and rear, for preventing slippage in the palm of a hand, and notches 13 at its front for receiving the fingers of the gripping hand. Two barrels 12 , 14 extend from the front of the water gun 1 .
[0021] A generally rectangular trigger guard 15 extends from the front of the grip 5 along the underside of the main body 7 and surrounds a trigger 17 having a surface 18 adapted to be pressed by an index finger for operating the water gun. On top of the trigger is a wall 16 (see FIG. 5A) from which a projection 20 extends rearwardly in axial alignment with a substantially cylindrical plunger 22 reciprocally slideable in a hollow cylinder 24 which leads into a water reservoir 26 having a filling opening which is covered by a threaded cap 28 best seen in FIG. 2.
[0022] Referring to FIG. 3, a hand pump 79 has a cylinder 81 in communication with the reservoir 26 . A plunger 83 is slideable within the cylinder 81 and has a handle 85 for reciprocating the plunger 83 to pump air into the reservoir 26 for pressurizing the water with it.
[0023] A plastic hose 30 has one end connected to a boss 32 surrounding an opening in the wall of the cylinder 24 and an opposite end connected to a central valve port 34 in a three-way valve 36 . A forward valve port 38 of the three-way valve 36 is connected to an inlet port of a T-fitting 40 having two outlet ports 42 , 44 . A hose 46 extends from one port 42 to an inlet opening 48 in a nozzle 50 mounted within a barrel 12 of the water gun 1 . A hose 52 extends from the other port 44 of the T-fitting 40 to an inlet opening 54 in a nozzle 56 mounted within a barrel 14 of the water gun 1 .
[0024] A hose 58 has one end connected to the third port 60 of the three-way valve 36 and an opposite end connected to a relief nozzle 62 mounted on the butt end of the water gun 1 enabling communication between the ambient atmosphere and the reservoir 26 .
[0025] With the trigger 17 at its rest position, passage of pressurized water from the reservoir to the hoses 46 and 50 is blocked. When the trigger 17 is pulled to its firing position, passage of pressurized water from the reservoir to the hoses 46 and 50 is enabled and water under pressure in the reservoir 26 is forced through the hoses 30 , 46 and 52 and expelled through the nozzles 50 , and 56 on respective barrels 12 , and 14 .
[0026] As can best be seen in FIGS. 5A and 5B, the trigger 17 has a floor 19 which projects rearwardly and terminates in an edge 21 engageable with a length of an electrically conductive resilient spring wire 23 , a segment of which is wound about a screw 25 threaded into an aperture 27 in a boss 29 integral with the interior of the housing 3 . The spring wire 23 urges the trigger in a forward direction toward a rest position for the trigger 17 as can best be seen in FIG. 5A. When finger pressure is applied to the trigger surface 18 , the trigger 17 moves rearwardly, pivoting the spring wire 23 back about the screw 25 and urging a free end 33 of the spring wire 23 into contact with a contact in the form of a cylindrical sleeve 35 made of a conductive metal and circumscribing a boss 37 integral with the interior of the housing 3 . A securing screw 39 is threaded into the boss 37 for holding the sleeve 35 in place.
[0027] Referring additionally to FIGS. 6 and 7, an end of the spring wire 23 opposite the free end 33 is electrically connected to one terminal of a power supply 47 in a compartment 49 within the housing 3 . The opposite terminate of the power supply is connected to the sleeve contact 35 .
[0028] The power supply contains three size C, 1½ volt batteries 51 connected in series for producing a voltage of 4½ volts. Connected in parallel with the series combination of the power supply 47 and a switch assembly 53 defined by the spring wire 23 and contact 35 are a motor assembly 55 and a sound assembly 57 .
[0029] The motor assembly 55 includes a direct current motor 59 , having a unidirectionally rotatable armature 61 which is part of a slider-crank mechanism. The sound assembly 57 includes a microcircuit with a memory on which there are digitally stored sounds imitative of the firing of an automatic weapon, a digital to analog converter, an amplifier and a speaker for producing audible sounds as will be known to those skilled in the art.
[0030] When the free end 33 of the spring wire 23 engages the contact 35 , the motor 59 is energized, and its armature 61 rotates. Referring to FIGS. 4 A- 4 C, the slider-crank mechanism includes a T-slide 63 slideably mounted on the housing of the motor assembly 55 an having an axial slot in which a boss 65 and cover screw 67 , connected to the housing of the motor assembly 55 , are received. A crank mounted on the armature 61 has a pin 69 disposed in a transverse slot 71 of the T-slide 63 for causing the T-slide 63 to reciprocate in an axial direction parallel to the barrels 12 and 14 as the motor armature 61 rotates.
[0031] A lever 71 is pivotally mounted, at a center opening, over a boss 73 and cover screw 75 fixed to the housing of the motor assembly 55 . A pin 75 on the T-slide 63 extends through an aperture adjacent one end of the lever 71 and is received in an aperture in the slideably mounted barrel 14 . A pin 77 extending from the barrel 12 , transverse to its axis, is received in an aperture adjacent an opposite end of the lever 71 . As the motor armature 61 rotates, the T-slide 63 reciprocates axially, causing the lever 71 to pivot back and forth, and the barrels 12 and 14 to reciprocate in synchronization, 180 degrees out of phase.
[0032] In use, the cap 28 is removed from the reservoir 26 and the reservoir 26 is filled with water, after which the cap 28 is replaced to seal the reservoir 26 . The pump handle 85 is then reciprocated to force air, under pressure, into the reservoir.
[0033] When the trigger 17 is pulled, fluid communication between the reservoir 26 and nozzles 50 , 56 permits water, under pressure, to be forced from the reservoir 26 through the nozzles 50 , 56 . Pulling of the trigger also urges the spring arm switch member 23 against the conductive sleeve 35 for completing a circuit between the power supply 47 and motor 59 , thereby causing the motor armature 61 to rotate, and the barrels 12 , 14 to reciprocate as water is squirted from the nozzles 50 , 56 . Closing of the switch member 23 also energizes the sound assembly 57 which emanates sounds simulating gunfire.
[0034] It is to be appreciated that the foregoing is a description of a preferred embodiment of the invention to which modifications may be made without departing from the spirit and scope of the invention.
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A toy water gun has a hand pump for pressurizing a reservoir of water and a trigger which controls a valve for allowing pressurized water to squirt from a nozzle when the trigger is pulled. A spring wire which normally urges the trigger toward a rest position engages a contact in response to pulling of the trigger whereby a circuit is completed to energize a motor which drives a slider-crank mechanism for causing reciprocation of the water gun's barrels, and to energize a sound circuit for simulating the sounds of gun fire.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 07/658,245 filed Feb. 20, 1991 titled Interlocking Fabric, Border Constructions and Frame now abandoned on Jun. 29, 1992.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates in general to stretching fabric on frames and in particular to retensioning fabric on frames as used in screen printing.
2. Prior Art
Screen printing involves the use of stretched fabric that is attached to a frame. Desirable attributes of screens are 1) that the fabric is very tightly stretched to a consistent tension, 2) that the fabric is held in place on the frame, and 3) that the fabric after it is coated with emulsion and has had an art pattern exposed onto the emulsion can be released from the frame with the art pattern intact and put into storage to be later restretched on the frame so as to accurately duplicate the tension level previously attained and to accurately match the placement of the art pattern in relation to the coordinates of the frame with the position previously attained. It is also desirable that this process be achieved quickly and easily and that fabric is not wasted. The oldest method of stretching fabric is with clamps that are pulled by hand, pneumatic pressure, or mechanically. Tension meters are used to determine the tightness of the screen fabric and adjustments are made to either loosen or tighten the fabric in order to approach a prescribed tension level. Once the tension level is reached, the fabric is glued or stapled to the frame. Once this is done, the fabric cannot be released from the frame without destroying the fabric. These methods do not solve the problem of restretching the fabric or address efficient and convenient storage.
I have observed that in one field of screen printing, i.e., that of printing on glass cylinders, in which relatively loose fitting stainless steel fabric is used, the fabric has border strips of extruded plastic along one axis that cup over flanges on the outside of the frame thus holding the fabric in place on two sides only. The other two edges of the fabric have border strips of metal that are crimped on to the stainless steel fabric and bolted to the frame. This construction is specifically designed to allow electric current to flow through the screen and heat the screen to melt a thermoplastic printing ink. It was observed that there are no means in this construction to significantly tighten the fabric. The two edges of the fabric with the extruded plastic border strips can only be loosely pulled by hand and cupped over the frame flanges. The construction of the plastic borders does not provide a means for attaching a clamp or any type of stretching device to pull the fabric tight enough to meet the tension requirements of most screen printers. Also, there is no indexing of the extruded plastic border strips along the frame flanges which means that the plastic borders, which are shorter than the flange, could vary in their placement along the flanges. Along the other axis at the other two edges, the metal border strips were observed to be crimped onto the stainless steel fabric and had holes through which they were bolted to the frame. With more than just a minimal tension along this axis, the fabric would tear loose, especially polyester fabric.
This device allows the fabric to be loosely stretched, released, and loosely restretched with an art pattern only approximating its original position in relation to the coordinates of the frame.
Widely used today are draw bar frames U.S. Pat. Nos. 3,482,343 and 3,553,862 and roller frames U.S. Pat. Nos. 3,908,293 and 4,345,390. The draw bar frame incorporates pulling clamps as part of the frame and roller frames allow the fabric to be rolled tightly by means of rollers that form the four sides of a frame. These devices solved the problem of how to stretch fabric, release it for storage, and restretch the same fabric at a later time. However, it still required the trial and error method of reaching a prescribed tension level with the use of a tension meter and there still was no way of restretching an art pattern back to its original position in relation to the coordinates of the frame.
In U.S. Pat. No. 3,991,677 of 1976 by V. H. Barnes entitled "Printing Screen and Tensioning Means" is described a frame structure with a stretching mechanism incorporated into the frame structure. Also described is a screen with border strips that attach to tension bars of the stretching mechanism. In U.S. Pat. No. 3,211,089 of 1962 by Elmar Messerschmitt entitled "Screen Printing Screen" is described a frame structure with a stretching mechanism incorporated into the frame. The Messerschmitt invention uses a continuous border around the fabric which attaches to an element of the frame. The frame expands telescopically thereby stretching the fabric. U.S. Pat. No. 3,416,445 of 1965 by T. H. Krueger entitled "Screen Stencil with Separate Border Strips" describes various border strips, fabric, and frames. One embodiment of this invention has two adjacent sides of the fabric with border strips attached to a frame on studs whereas the other two opposite sides are pulled outward by flexible straps pinned to the border strips and wrapping around rotating crank shafts that are part of the frame. These flexible straps are all that hold these two border strips in place on this frame. Another embodiment of this invention features L shaped border strips. A third embodiment features a rigid continuous border that cannot be stretched and is fundamentally a frame attached to another frame.
The Barnes, Messerschmitt, and Krueger inventions require stretching mechanisms that are incorporated into the frames. The stretching mechanisms have moving parts which, like draw-bar frames and roller frames, are added expenses in the construction of the frames and add extra weight to the frames. These stretching mechanisms with their moving parts are exposed to the every day spraying, washing, and rinsing of the screens with water, cleaning compounds, solvents, and inks. They are subjected to the wear and tear of shop operations which usually includes a significant amount of mechanical shock. These parts, of course, depreciate under these severe conditions.
These three inventions do not utilize locking mechanisms that secure all four fabric edges into definite fixed positions on the frames. The Barne's invention does not have any pins, studs, abutments, etc. to fix the exact lateral location of the border strips on the tension bars. The Messerschmitt invention's continuous border is of a flexible material that stretches and is therefore unreliable as an aligning feature, particularly after repeated uses. The Krueger invention utilizes studs on two sides only to fix the locations of two unmoveable border strips. These two border strips do not at any time move to a more outward position on the frame. The other two border strips are attached to flexible straps which are unreliable as aligning features. Also, by only outwardly moving two border strips, the corner area between the stationary strips is under very little tension and the area between the two outwardly moved border strips is under extremely high tension. The tension throughout the fabric, because of the stretching method employed by this invention, is very inconsistent. This tension inconsistency in the fabric similarly exists in the L shaped border strips embodiment of this invention.
In none of the above cited references is there an inflexible aligning feature providing reliable alignment for a border strip that is moved to a more outward position. In none of the above cited references is there a discussion, object, or claim of controlling the stretch distances of the fabric along the X and Y axis by establishment of exact start and stop positions of the border strips so as to effect precalculated stretch distances for fabric of precalculated size and shape.
Whatever the precise merits, features, and advantages of the above cited references, none of them achieves or fulfills the purposes of the interlocking screen fabric, border strips and frames of the present invention.
SUMMARY OF THE INVENTION
A principal object of the present invention is to provide a quicker and easier means of attaching a screen fabric to rigid frames and roller frames so as to achieve a prescribed tension level in the fabric.
Another principal object of the invention is to provide a means of quickly and easily releasing the fabric from rigid frames and roller frames for convenient and economical storage after the fabric has been coated with emulsion and has had an art pattern exposed onto the screen and to provide a means of restretching the fabric and reattaching it to the frame so as to accurately duplicate the placement of the art pattern in relation to the coordinates of the frame with the placement of said art pattern previously attained.
In order to achieve a prescribed tension level in the fabric, the fabric and frame must be designed so that the fabric is of a prescribed size and shape in relation to the frame. The fabric has strips of rigid/semi-rigid material attached along the borders of all four fabric edges which are of a prescribed length, width, and position on the fabric border. The fabric edges extend laterally beyond the length of the strips so that the edges of the fabric are free and open in the fabric corner areas. For a rigid frame application, the strips are designed to easily attach to a variety of external stretching devices. For roller frames, the strips are designed to easily attach to the rollers. Each and every strip is designed to align and lock into a prescribed section of the frame.
The locking sequence with a rigid frame is to lock the first side of the fabric to the rigid frame in its prescribed place manually, attach the external stretcher device(s) to the strip on the opposite side, stretch the fabric until the border strip fastening features line up with the fastening features of the frame, and lock the side onto the frame. Next step is to attach the stretching device(s) to the fabric border strips along the other axis of the fabric, stretching both remaining sides and locking them onto the frame in a similar manner. Because the fabric has a precalculated stretch distance along the X and Y axis, the tension in the fabric will reach a prescribed level. The coordinates of the fabric will also become positioned in a consistent pattern.
The border strips can be held in place on the frame by means of an abutment flange on the border strip that slides over the outside edge of the rigid frame and snaps down into place over the rigid frame edge. The strips can then be more firmly secured in place with fasteners. There are a multiplicity of fastening devices which may be used within the scope of this invention.
With some fabric materials there is a predictable relaxing or loosening of the fabric within the first few hours after stretching. This is true, for example, with polyester fabrics. The polyester fabric will, however, stabilize at a prescribed tension if it is stretched in additional increments after it relaxes or loosens. To continue stretching, the stretching sequence is repeated with successively outward placements of all the border strips on the frame with the stretcher device.
In order to facilitate further stretching of the fabric, flange adaptors can be inserted between the border strip abutment flanges and the rigid frame as the border strips are pulled outward by the stretching device(s). The flange adaptors are held in place by the inward pull of the fabric which causes the border strips to pull inward against the flange adaptors pressing them against the sides of the rigid frame. The adaptors help to align a new set of fastening features on the border strips and frame. They also continue to provide additional support for the border strips in conjunction with the abutment flanges. Additional flange adaptors as well as additional fastener features on the border strips and frame permit successively greater stretching of the fabric.
Although this invention foresees an economic advantage in the use of just one set of external stretcher devices for an unlimited number of rigid frames with the rigid frames being more durable, lighter, less bulky, and less expensive than roller frames, this invention also includes utilization of roller frames to perform essentially the same function as rigid frames.
The steps used to stretch fabric with a roller frame are quite different than the steps used to stretch fabric with a rigid frame. The basic stretching action exerted on the fabric, however, is the same. Whereas a rigid frame depends upon external stretching devices, the rollers of a roller frame are themselves the stretching devices. In the fabric, border constructions and rigid frames of the present invention, the abutment flanges, flange adaptors, and fastener features provide precise stop positions for stretching the fabric. The fabric has a controlled stretch distance since the size and shape of the fabric are precisely controlled and provide an exact stretching start position. In order to have this same control in a roller frame it is necessary to control the stop positions of the rollers and to precisely control the size and shape of the fabric as well as the size, shape, and location of the border strips. All roller frames have features which permit the rollers to be rotated and locked in place. However, they lack a means of precisely controlling where the roller is locked in place. In order to achieve a precise stop position of the rollers, it is necessary to add a feature to the roller frames that does not exist in the prior art. This feature is a pin locator or indexing feature. By incorporating bores with support housings on the corner members of roller frames through which pins can be inserted into recesses on the roller end plugs, the rotational travel of the rollers can be precisely controlled. After aligning the roller so that the pin can be inserted through the end member bore into a roller recess, the roller is subsequently locked into position with whatever locking features the roller frame employs. The distance that the fabric is stretched is thereby controlled.
The fabric in a roller frame application is attached to border strips in the same manner as with rigid frames. However, the border strips need not have attachment flanges to attach to external stretcher devices or abutment flanges to add strength to the border strips and facilitate alignment. These are unnecessary with roller frames of the present invention. The border strips are merely designed so as to insert within a channel of the roller so as to align fastening features of the border strip and roller. These fastening features may cooperate with pins, screws, studs, etc. that securely fasten the border strip and roller together in a precise location. The border strip may comprise a cupped shape which hooks over a flange in the roller channel with alignment being accomplished through the abutment caused by the length of the strip being the same as the length of the channel. As with a rigid frame of the present invention, it is necessary that the border strips, fabric, and roller frame be of prescribed sizes and shapes and that the border strips be at prescribed locations on the fabric so that there is a controlled stretch distance of the fabric along both the X and Y axis.
The locking sequence with a roller frame is to align all four rollers in a start position by rotating the rollers to a position such that locator pins are inserted into designated recesses in the rollers and the rollers are locked in place by the locking features of the roller frame. Next step is to insert all four border strips into the roller channels. If the border strips have fasteners such as screws, these are fastened in place at this time. Next step is to take the locator pin out of one roller and rotate the roller so that the locator pin can be reinserted at a designated advanced recess on the roller. The roller is then locked in place by the locking features of the roller frame. The roller recess locations are precalculated so as to achieve a prescribed stretch distance in the fabric. By rotating each roller in this manner, the fabric is stretched a prescribed distance in both the X and Y axis. This will achieve a prescribed tension in the fabric. Because some fabrics will relax or loosen in predictable amounts within the first few hours of stretching, it may be necessary to continue stretching the fabric by rotating the rollers so as to align the pins to even more advanced recess locations. These more advanced recesses are located so as to produce precalculated additional stretch distances of the fabric. In this manner the tension of the fabric can be stabilized at a prescribed level.
For both rigid frame and roller frame applications the fabric can be released easily and quickly by reversing the attachment process. Because the fabric and border strips are much thinner than the frame and represent a much less overall cost to the screen printer than the combined fabric and frame, the printer can inexpensively store fabric with art using very little space. Storing and reusing screens according to the present invention spares the printer the time and cost of coating and exposing the same art pattern again at a later time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective drawing of one embodiment of the rigid frame of the present invention as seen from the bottom or print side.
FIG. 2 is a perspective drawing of a second embodiment of the rigid frame of the present invention as seen from the bottom or print side.
FIG. 3 is a perspective drawing of the fabric and rigid/semi-rigid border strips of the present invention as seen from the bottom or print side.
FIG. 4 is a perspective drawing of one embodiment of the rigid/semi-rigid border strip of the present invention.
FIG. 5 is a perspective drawing of one embodiment of the flange adaptor of the present invention.
FIG. 6 is a perspective drawing of a second embodiment of the rigid/semi-rigid border strip of the present invention.
FIG. 7 is a perspective drawing of a second embodiment of the flange adaptor of the present invention.
FIG. 8 is a perspective drawing of a third embodiment of the rigid/semi-rigid border strip of the present invention.
FIG. 9 is a perspective drawing of a fourth embodiment of the rigid/semi-rigid border strip of the present invention.
FIG. 10 is a perspective drawing of one embodiment of a stretching device for a rigid frame.
FIG. 11 is a perspective drawing of a corner member and roller end plug of a roller frame of the present invention.
FIG. 12 is a perspective drawing of a roller channel of a roller frame of the present invention.
FIG. 13 is a cross sectional view of one embodiment of the roller of a roller frame of the present invention.
DETAILED DESCRIPTION
The interlocking fabric, border constructions and frames of the present invention includes a rigid frame as in FIGS. 1 and 2 and it includes fabric with rigid/semi-rigid border strips as in FIG. 3.
Referring to FIGS. 1 and 2, the rigid frame can be made of any solid material such as stainless steel, aluminum, wood, plastic, etc. The top surface, 21, in and adjacent to the corners are elevated above the surfaces, 22, between the corners. Fastening features, 23, are constructed into the surface areas, 22, at predetermined locations. These allow for precisely measured successively outward placement of the border strips. Channels, 24, are hollowed out of the surface areas, 21, and run along the corners as seen in the drawing. Insertion recesses, 25, are at precalculated locations on the rigid frame outside wall, 27, so as to align and secure stretcher devices to the rigid frame.
FIG. 2 shows flanges, 26, that extend outward beyond the outside wall, 27, of the rigid frame.
FIG. 3 shows the fabric, 31, that is of a precalculated size and shape in relation to the size and shape of the rigid frame. The fabric is glued, molded inserted, etc. onto the outward facing surface, 33, of the border strips, 32. The border strips are constructed out of a solid material such as plastic, stainless steel, aluminum, wood, etc. and must be strong enough and rigid enough to provide a sufficient medium for pulling the fabric and holding it in place while under tension. The border strips are attached to the fabric in precise precalculated locations in relation to the coordinates of the fabric and the rigid frame or roller frame so as to produce a precise and precalculated tension in the fabric when the border strips are pulled to their precalculated stop positions on the rigid frame. The strips are of an exact length to align themselves with the lower surface level, 22, of the rigid frame of FIGS. 1 and 2 and slide in between the higher corner sections, 21, of FIGS. 1 and 2. The thickness of the border strips is designed to exactly match the difference in height between the lower and upper surface levels of the rigid frame. The fabric, which is on the outward facing surface of the strips aligns with the elevated surface of the corner sections when the border strips are pulled into position along surface areas, 22, of FIGS. 1 and 2.
Referring to FIGS. 4 and 6, drawings of the preferred embodiments of the border strips for rigid frames are shown. The outward facing surface, 41, of FIG. 4 and, 61, of FIG. 6 is flat. This surface is glued to or molded to the fabric. The thickness, 42, of FIG. 4 and, 62, of FIG. 6 of the strips is such as to provide for a flat surface along the entire frame bottom once the strips are pulled into position between the corners of the rigid frame. Likewise, the length of the strips is such as to provide for an exact fit between the corner sections. With predetermined locations so as to align with fastening features, fastener holes, 43, of FIG. 4 and, 63, of FIG. 6 are manufactured into the border strips. These holes are in predetermined locations to control precisely measured outward placements of the border strips. These holes may be reinforced with metal eyelets. Once the border strips are pulled into place, they may be fastened onto the rigid frame at these points with pins, screws, bolts, or any such fastening devices (1).
Attachment flanges, 44, of FIG. 4 and, 64, of FIG. 6 extend beyond the leading edge of the border strips to permit hooking or clamping by stretcher devices. The attachment flanges may have holes, 46, of FIG. 4 and, 66, of FIG. 6 which may be reinforced with metal eyelets. FIG. 4 shows an abutment flange, 45, at a right angle that is ideal for the rigid frame as shown in FIG. 1. The abutment flange slides across surface, 22, in FIG. 1 and snaps over the edge of the rigid frame. It facilitates the exact alignment of the border strip because the inward pull of the fabric presses the abutment flange firmly against the rigid frame outside wall, 27, once the stretcher device is released. It also provides added strength to the border strip and compensates for any flexibility in the border strip material.
FIG. 5 shows a flange adaptor that can be used with the border strip of FIG. 4. Said adaptor is inserted between the abutment flange, 45, of FIG. 4 and the frame outside wall, 27, of FIG. 1 when the border strip is pulled to a more outward position. The frame adaptor is held in place between the border strip and the abutment flange by the inward pull of the fabric once the stretcher device is released. The flange adaptor serves the useful purpose of facilitating the alignment of the new fastening features associated with the more outward location of the border strip. The flange adaptor is of a precalculated width, 51, to provide a precalculated new stop position for the border strip and provide a precalculated new stretch distance of the fabric. It also helps the abutment flange to continue adding strength to the border strip.
FIG. 6 shows a border strip design with a cupped shape, 65, on one edge. This border strip is designed to hook over the flange, 26, of FIG. 2 of the rigid frame. The cupped edge serves essentially the same purpose as the abutment flange, 45, of FIG. 4. In all other respects the border strip of FIG. 6 is the same as the border strip of FIG. 4.
FIG. 7 shows a flange adaptor that can be used with the border strip of FIG. 6. It performs the same functions as the flange adaptor of FIG. 5 and is so shaped so as to easily fit within the cupped shape, 65, of the border strip of FIG. 6. The shape of this adaptor is designed to provide a new cupped shape, 72, to cup over the flange, 26, of FIG. 2.
FIG. 10 is a drawing of a stretcher device suitable to use in conjunction with the current invention. The shafts, 101, are inserted into the insertion recesses, 25, of FIGS. 1 and 2. The pin, 102, of FIG. 10 is then inserted into the flange hole, 46, of FIG. 4 or, 66, of FIG. 6. By rotating the screw, 106, with the handle, 107, the border strip is moved up or down. By rotating the screw, 104, with the handle, 103, the assembly, 105, is pulled away from or toward the rigid frame, moving the border strip with it. With this device, it is possible to pull the border strips outward and downward in place against the rigid frame by merely rotating the handles in a coordinated way. Reversing the process will release the border strips.
Once a border strip has been located into place by a stretcher device, the action of the abutment flanges, 45, of FIG. 4 or cupped edge, 65, of FIG. 6 and the flange adaptors of FIG. 5 and FIG. 7 hold the border strips in place on the rigid frame. By next fastening the border strips onto the rigid frame with pins, screws, bolts, or other devices, the border strips and fabric are securely locked on the frame.
The fabric extending over the corner sections of the rigid frame can be lightly glued, taped, or fastened down in the channel, 24, of FIGS. 1 and 2 with the insertion of cords over the fabric and into the channels.
FIG. 8 and FIG. 9 show border strips designed for roller frames. They are identical to the border strips of FIGS. 4 and 6 except that they do not have abutment flanges or attachment flanges and they may not be as wide.
FIG. 12 shows a roller of a roller frame. A channel, 121, is of a prescribed length, width, depth, and location on the roller frame so as to receive the border strip of FIG. 8. Fastener features, 122, align with the fastener features, 83, of FIG. 8.
The thickness, 82, of the border strip of FIG. 8 is exactly calculated to provide for insertion into the channel, 121, of FIG. 12.
FIG. 13 shows a cross section of a roller with a channel, 131, that has a flange, 132, constructed into the inner wall of the channel. The thickness, 92, of the border strip of FIG. 9 is such as to provide for the insertion of said border strip into the channel, 131, of FIG. 13. The cupped edge, 94, of said border strip is such as to cup over said flange of said roller.
FIG. 11 shows a roller frame corner member and roller end plug. The corner member, 115, has a bore, 112, with surrounding housing, 114, through which a pin, 111, can be inserted. Said pin upon being inserted through said bore is inserted into recesses, 113a, 113b, 113c, 113d, and 113e of the roller end plug, 116. The said end plug recesses serve as aligning features of the roller frame. Recess, 113a, is an alignment feature for the start position in stretching a fabric. Since the roller frame construction consists of four rollers each connected by a corner member, all four rollers can be locked down by the locking features of the roller frame into start positions as determined by the location of the recess, 113a, of each roller end plug. The fabric of the invention, as in the rigid frame application, is of a prescribed size and shape in relation to the roller frame. The border strips and roller channels are of a prescribed size, shape, and location relative to the coordinates of the roller frame. Recess, 113a, exactly controls the start position of the stretching process. By unlocking each roller and rotating it to an advanced recess of a precalculated location on the roller end plug, the stretch distance of the fabric can be controlled and predetermined just as in a rigid frame application. All of the variables of the stretch distance; the fabric size and shape, the frame size and shape, the start position, and stop positions are precalculated and prescribed. The fabric stretch distance and, hence, the fabric tension are controlled. This control is further exercised over the positioning of all coordinates of the fabric on the frame.
The foregoing description of the preferred embodiments of the invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms described. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto.
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The invention relates to screen fabric, fabric border constructions, and screen frames. The fabric border constructions and frame are of a size and shape so as to releaseably fit and lock together. The fabric is attached to the border constructions and is of a size and shape in relation to the frame so as to be stretched to a precalculated tension upon being acted upon by the placement of the border strips on the frame. The invention provides for the border constructions and fabric to be released from the frame and later reattached duplicating the tension and placement of all coordinates of the fabric in relation to coordinates of the frame.
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[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60/466,496, filed Apr. 29, 2003, the entire content of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates to delivery of social services and, more particularly, to client management tools for social services organizations.
BACKGROUND
[0003] Social service organizations, such as homeless shelters, domestic violence support providers, state and country governments, information and referral agencies, and food shelves, deliver a variety of social services to clients in need. Some social services clients can be itinerant, and may seek services from more than one social service organization, or more than one facility within a single social service organization. In addition, some clients may use social services on an infrequent or erratic basis. In some instances, social services organizations can encounter security or other safety risks in the course of serving particular clients. In view of these and other factors, management of the relationships between one or more social services organizations and their clients can be difficult.
SUMMARY
[0004] The invention is directed to a client management system for social service organizations. In addition, the invention is directed to methods that may be implemented by a client management system.
[0005] The client management system provides a powerful, convenient, and easy-to-use system for management of client relationships within a social service organization. The client management system may be useful in a variety of social service organizations including, for example, homeless shelters, domestic violence support providers, state and country governments, information and referral agencies, and food shelves.
[0006] The client management system may facilitate client intake, delivery of services, case management, data sharing among different organizations or facilities within a single organization, security monitoring, and custom reporting. In some embodiments, for example, the client management system may support controlled access to facilities such as homeless shelters, and enable verification of admission of individuals to a shelter.
[0007] The client management system may utilize client credentials, such as identification cards, fobs, tags, keys, or other media carrying information that identifies a client. An identification card, for example, may carry human-readable information such as a photo, name and other client information, as well as machine-readable information encoded in a data carrying medium such as a magnetic stripe, bar code, radio frequency identification tag, or smartcard chip.
[0008] When a client seeks access to a facility, the client management system reads the client credentials and queries a database. The database may store a variety of client information such as information concerning intake dates, family information, services provided, observation histories, incident histories and the like. The client management system may use the information stored in the database to recommend a course of action for social service organization personnel.
[0009] For example, upon presentation of the client credentials, the client management system may invoke an incident/observation tracking module to determine whether the database indicates any security or safety incidents for the client. If so, the client management system may generate an advisory to refuse admission to the client.
[0010] In addition, in a homeless shelter, the client management system may invoke a housing module to track applications for and usage of housing by clients. For example, the housing module may track government-sponsored housing contracts, such as HUD contracts, and other information relating to short-term, transition, and long-term or permanent housing. In addition, the housing module may record data about the clients who are using housing resources, enabling ready reporting and record keeping, e.g., to satisfy government regulatory requirements. Also, the housing module may record length of stay information. In some cases, the housing module may further be configured to aid in a search for housing accommodations for the client. In this case, the housing module may commence an automated workflow for matching the client with a housing opportunity.
[0011] As a further option, the client management system may invoke a direct services module that manages scheduling and allocation of services to clients. The direct services module may commence an automated workflow for delivery of selected services to the client.
[0012] Also, the client management system may provide a reporting module that supports collection, presentation and analysis of information concerning clients and utilization of services. In this manner, the social services organization can evaluate its own performance and the value of the services provided to clients.
[0013] In one embodiment, the invention is directed to a method in which a client credential card is read to identify a client of a social service organization, data associated with the identified client is retrieved from a database, and it is determined whether the identified client is permitted to receive a service provided by the social service organization based on the retrieved data.
[0014] In another embodiment, the invention is directed to a client management system that includes a database to store data associated with a client of a social service organization, a card reader to read a client credential card associated with the client, and an access workstation coupled to the card reader. The access workstation identifies the client based on data read from the client credential card, retrieves at least some of the data associated with the client from the database, and determines whether the client is permitted to receive a service provided by the social service organization based on the retrieved data.
[0015] In another embodiment, the invention is directed to a computer-readable medium comprising instructions. The instructions cause a programmable processor to identify a client of a social service organization based on data read from a client credential card, retrieve data associated with the identified client from a database, and determine whether the identified client is permitted to receive a service provided by the social service organization based on the retrieved data.
[0016] In another embodiment, the invention is directed to a method in which data associated with clients of at least one social service organization is collected, the data for each of the clients including identification data, a record is created within a database for each of the clients, each of the records including at least some of the data collected for the respective client, and a client credential card is generated for each of the clients, wherein each of the client credential cards includes at least a portion of the data for the respective client. The method further includes reading the client credential cards to identify clients when the clients attempt to receive services provided by the social service organization, and updating the records within the database based on services received by the clients to track usage of the services by the clients.
[0017] In another embodiment, the invention is directed to a client management system including a database, an intake workstation, and an access workstation. The intake workstation collects data associated with clients of at least one social services organization, the data for each of the clients including identification data, creates a record within the database for each of the clients, each of the records including at least some of the data collected for the respective client, and controls a card printer-to generate a client credential card for each of the clients, wherein each of the client credential cards includes at least a portion of the data for the respective client. The access workstation reads the client credential cards via a card reader to identify clients when the clients attempt to receive services provided by the social service organization, and updates the records within the database based on social services accessed by the clients provided by the social service organization to track usage of the services by the clients.
[0018] The invention may provide a number of advantages. In general, the client management system can help a social service organization to more accurately track the clients who uses its services. With this enhanced tracking capability, the social service organization can more efficiently and effectively deliver services to its clients. In addition, the social service organization may be able to reduce safety and security risks by recording incidents involving particular client and quickly verifying the presence of an individual client within a facility should the need arise. Also, the client management system may be configured for sharing of information among multiple facilities or social service organizations. As another advantage, the client management system may support automation of various activities, including delivery of direct services and housing services. Further, the reporting capability provided by the client management system can serve as a powerful tool in performance and value analysis.
[0019] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF DRAWINGS
[0020] FIG. 1 is a block diagram illustrating a client intake system forming part of a client management system for a social services organization.
[0021] FIG. 2 is a front view of a client credential card produced by the client intake system of FIG. 1 .
[0022] FIG. 3 is a back view of a client credential card produced by the client intake system of FIG. 1 .
[0023] FIG. 4 is a block diagram illustrating a client access system forming part of the client management system for a social services organization.
[0024] FIG. 5 is a block diagram illustrating implementation of the client management system on a shared basis among multiple facilities or social services organizations.
[0025] FIG. 6 is a block diagram illustrating modules running on the client access workstation shown in FIG. 4 .
[0026] FIG. 7 is a flow diagram illustrating a client intake process within the client management system.
[0027] FIG. 8 is a flow diagram illustrating a client access process within the client management system.
[0028] FIG. 9 illustrates an example client tracking screen presented by the client management system.
[0029] FIGS. 10 and 11 illustrate example client record screens presented by the client management system.
[0030] FIG. 12 illustrates an example client facility access record screen presented by the client management system.
[0031] FIG. 13 illustrates an example housing intake screen presented by the client management system.
[0032] FIG. 14 illustrates an example services screen presented by the client management system.
[0033] FIG. 15 illustrates an example behavioral report screen presented by the client management system.
[0034] FIG. 16 illustrates an example report generator screen presented by the client management system.
[0035] FIG. 17 illustrates an example report screen presented by the client management system.
[0036] FIGS. 18-23 illustrate example client data intake screens presented by the client management system.
DETAILED DESCRIPTION
[0037] FIG. 1 is a block diagram illustrating a client intake system 10 forming part of a client management system for a social services organization in accordance with the invention. As shown in FIG. 1 , system 10 may include an intake workstation 12 , a camera 14 , a user interface 16 , a card printer 18 and a database 20 . Client intake system 10 collects client information and generates client credential cards to be carried by clients. Client intake system 10 may be installed near an entrance to a social service organization facility for processing of new clients.
[0038] Intake workstation 12 may take the form of a personal computer or computer workstation. User interface 16 may include a display, keyboard, pointing device and the like. Camera 14 may take the form of a digital camera that captures a digital photo of a client and transmits the photo to intake workstation 12 , e.g., via a USB interface or removable media reader. Card printer 18 may take the form of a conventional card printing system, and may produce single layer printed cards or laminated cards.
[0039] Database 20 may take a variety of forms, and may store data within in any type of data structure, including a relational data structure. In one embodiment, database 20 may be realized by Lotus Notes database. In this case, database 20 may include a Lotus Domino server running on server platform, such as an IBM AS400 server running the OS/400 operating system. Intake workstation 12 may run a version of Lotus Notes, and access database 20 via a network connection. An intake software application may be loaded onto intake workstation 12 to drive collection of client data via user interface 16 .
[0040] The intake software application may be implemented as a Lotus Notes application. A card generation application running on workstation 12 drives printing of client credential cards via card printer 18 . An example of a suitable card generation application is the IDWorks software application commercially available from Datacard Corporation of Minneapolis, Minn. The card generation application may collect data from the Lotus Notes application or records within database 20 to place within fields in client credential cards printed by card printer 18 . The reference to particular software applications and database platforms herein is for purposes of illustration and should not be considered limiting of the invention.
[0041] FIG. 2 is a front view of a client credential card 22 produced by client intake system 10 of FIG. 1 . In the example of FIG. 2 , client credential card 22 includes a client photo 24 , an organization field 26 , a name field 28 , a birth date field 30 , and intake date field 32 and an identification code 34 . Photo 24 includes a photo obtained by camera 14 ( FIG. 1 ). Organization field 26 contains the name of the pertinent social services organization. Name field 28 contains the name of the client. Birth date field 30 contains the birth date of the client. Intake date field 32 contains the date the client was first processed for intake by the social services organization. Identification code 34 may be an alphanumeric code that uniquely identifies the client. The information on the front side of client credential card 22 may be, in general, human-readable.
[0042] FIG. 3 is a back view of client credential card 22 produced by client intake system 10 of FIG. 1 . In the example of FIG. 3 , client credential card 22 includes a magnetic stripe 36 that magnetically encodes information in a machine-readable format. As further options, client credential card may include a machine-readable bar code 38 , an embedded radio frequency identification (RFID) tag 40 , or a smartcard chip (not shown). The machine-readable information encoded in magnetic stripe 36 , bar code 38 and RFID tag 40 may present some or all of the information presented in human-readable form on the front side of client credential card 22 , and may include additional information not presented in human-readable form on the front side of the card. Client credential card 22 may be formed from plastic or other conventional materials typically used for identification cards.
[0043] FIG. 4 is a block diagram illustrating a client access system 42 forming part of the client management system for a social services organization in accordance with the invention. As shown in FIG. 4 , client access system 42 may include an access workstation 44 , a user interface 46 , a card reader 48 , and database 20 . Client access system 42 may be located near an entrance to a social service organization facility to process existing clients for access and admission to services.
[0044] Access workstation 44 may take the form of a personal computer or computer workstation. User interface 46 may include a display, keyboard, pointing device and the like. Card reader 48 may be a magnetic stripe reader, bar code reader, RFID reader, or the like. Facility personnel may inspect human-readable information printed on a client credential card 22 . Card reader 48 reads the machine-readable information carried by client credential card 22 .
[0045] In response to the information obtained by card reader 48 , access workstation 44 queries database 20 for additional information associated with the client. Like intake workstation 12 , access workstation 44 may run a database application, such as Lotus Notes, to access database 20 . As will be described, access workstation 44 may run processes that facilitate delivery of services to clients, security and safety monitoring, and reporting and analysis of organizational statistics. Advantageously, the Lotus Notes platform also may support an automated workflow to generate and send forms, emails, and other messages associated with an intake, services, security or housing activity.
[0046] FIG. 5 is a block diagram illustrating implementation of a client management system 50 on a shared basis among multiple facilities or social services organizations. As shown in FIG. 5 , multiple access workstations 44 A- 44 N (hereinafter 44 ) and intake workstations 12 A and 12 B (hereinafter 12 ) may access a common database 20 via a network 52 . Network 52 may be any network, and may include one or more of a local area network (LAN), the Internet, the Public Switched Telephone Network (PTSN), or a wireless communication network.
[0047] Each of intake workstations 12 may have full or limited access to database 20 to create new client records. Further, each of access workstations 44 may have full or limited access to the records stored in common database 20 to read information from database 20 , and to modify the contents of records within the database. With shared access to a common database 20 , multiple facilities within a given social service organization or multiple social service organizations can exchange information concerning individual clients to enhance overall services, minimize security and safety risks, or report and analyze overall service delivery and client statistics.
[0048] FIG. 6 is a block diagram illustrating exemplary modules running on client access workstation 44 shown in FIG. 4 . As shown in FIG. 6 , client access workstation 44 includes an incident/observation tracking module 54 , a housing module 56 , a direct services module 58 , and a reporting module 60 .
[0049] Incident/observation tracking module 54 , upon identification of a particular client, queries database 20 for information concerning past incidents or observations involving the client. A record of previous incidents or observations may serve to identify client that pose a safety or security risk. An incident, for example, may refer to a past event involving violent or hostile behavior by the client, or perhaps criminal activity. An observation may refer to notes recorded by facility personnel concerning suspicious or questionable activity by the client. In each case, retrieval of information from database 20 concerning a prior incident or observation may serve as a warning to increase security. In one embodiment, access to a facility is denied based on incidents or observations recorded within database 20
[0050] In some embodiments, incident/observation tracking module 54 may be configured to generate a security advisory on an automated basis. In addition, incident/observation tracking module 54 may present an interface for facility personnel to enter information concerning new incidents or observations. In a shared arrangement as shown in FIG. 5 , multiple facilities or multiple organizations may have access to such information. As a further feature, incident/observation tracking module 54 may permit immediate verification of whether a particular client has been granted access and is on the premises of a facility. This feature may be useful when a security or safety risk is identified, e.g., by law enforcement, after admission of the client to the facility.
[0051] Housing module 56 tracks application for and usage of housing by clients. For example, the housing module may track government-sponsored housing contracts, such as HUD contracts, and other information relating to short-term, transition, and long-term or permanent housing, and store the information in database 20 . In addition, housing module 56 may record data about the clients who are using housing resources in database 20 , enabling ready reporting and record keeping, e.g., to satisfy government regulatory requirements. Also, the housing module 56 may record length of stay information. In some embodiments, housing module 56 also may query database 20 for housing opportunities that may be available to the client. The housing opportunities may be presented, for example, when the present facility, e.g., a homeless shelter, is fully booked and has no available space. In this case, the database 20 may be loaded with housing opportunities at other facilities in a local area, and may take advantage of a shared arrangement as shown in FIG. 5 .
[0052] Alternatively, housing module 56 may be configured to identify permanent or longer-term housing opportunities, such as low income or subsidized apartments and the like. Housing module 56 may identify appropriate housing opportunities based on location and demographic information associated with the client, such as gender, age, ability, family situation or the like. Housing module 56 may be configured to automatically commence one or more workflow items necessary to secure housing such as generation of housing application forms, generation of emails to appropriate housing decision makers, and the like.
[0053] Direct services module 58 may query database 20 for a services history for the particular client. Based on the services history, facility personnel may determine whether delivery of additional services is necessary or timely. In this case, direct services module 58 may present an interface for entry of service requests, including scheduling options. In some embodiments, direct services module 58 may automatically commence one or more workflow items for delivery of services, such as scheduling of particular services, ordering of supplies for delivery of the services, and the like. Examples of particular direct services that may be provided to clients include food shelf access, telephone access, first aid, showers, storage, mail services, distribution of furniture vouchers, bus tokens, diapers and formula, and referrals to other facilities or organizations. Other services arranged by the facility may include health care and employment counseling.
[0054] Reporting module 60 may be responsive to entries made by facility personnel via a reporting interface. For example, the facility personnel may request reporting of statistics for particular clients, groups of clients, particular services, and the like. In response, reporting module 60 retrieves pertinent data from database 20 , and renders one or more reports based on the data. In this manner, reporting module 60 supports collection, presentation and analysis of information concerning clients and utilization of services. Facility personnel can analyze the reports and evaluate a variety of facility or organizational characteristics, such as performance and value of the services provided to clients. This type of analysis may be important not only for operational efficiency, but also justification for state and federal funding of services. Further, this analysis may enable ready reporting and record keeping to satisfy government regulatory requirements.
[0055] FIG. 7 is a flow diagram illustrating a client intake process within the client management system 50 . As shown in FIG. 7 , the intake of a new client may involve generating an image of the new client ( 62 ), e.g., a digital photo taken by a camera 14 of an intake system 10 , and inputting new client data ( 64 ) such as name, gender, birth date, height, weight, eye color, hair color, complexion, ethnicity, family contact information, and the like via a user interface 16 and an intake workstation 12 . The process may further involve inputting housing data ( 66 ), such as last permanent address, and inputting direct services data ( 68 ), such as identification of particular services desired by the client via the user interface 16 and the intake workstation 12 . Upon creation of entries ( 70 ) within a database 20 in accordance with the inputted data, e.g., a client record, the process further involves generating a client credential card 22 ( 72 ), e.g., by the intake workstation 12 and card printer 18 .
[0056] FIG. 8 is a flow diagram illustrating a client access process within the client management system 50 . As shown in FIG. 8 , the client access process may involve reading a client credential card 22 ( 74 ), obtaining identification data from the card 22 ( 76 ), and mapping the identification data to database entries within a database 20 ( 78 ). In some cases, a card reader 48 of an access system 42 reads machine-readable identification data from the card 22 , and an access workstation 44 maps the data to entries within database 20 . In other cases, a user reads human-readable identification data from the card 22 , and enters the identification data into the access workstation 44 via a user interface 48 so that the access workstation may map the data to the entries.
[0057] The process may further involve querying the status of one or more modules. In one embodiment, an incident/observation tracking module queries the database 20 for any incident reports ( 80 ). In the example of FIG. 8 , the access workstation 44 may generate an advisory ( 82 ) in the event an incident report is identified for the particular client. If no incident reports exist, the client is permitted to access the facility ( 84 ).
[0058] In another example, the process querying of direct services status by a direct services module 58 ( 86 ). For example, if the client is due for a particular service, the access workstation 44 may automatically commence a direct services workflow to request or schedule particular services ( 88 ). In addition, housing status may be queried by a housing module 56 ( 90 ), e.g., for space in other facilities or permanent or temporary housing. In one embodiment, access workstation 44 automatically commences a housing workflow to secure housing accommodations for the client ( 92 ).
[0059] Upon querying the status of one or more modules, database 20 may be updated ( 94 ). Specifically, a person using access workstation 44 or access workstation 44 itself may modify or update data within the database, such as data within a record of the client who is currently seeking access to the facility. As an example, the record of the client may be updated to reflect admittance to a facility and any services scheduled for or provided to the client.
[0060] FIG. 9 illustrates an example client tracking screen 100 that may be presented by a display of a user interface 46 of an access system 42 of the client management system 50 . In the example of FIG. 9 , client tracking screen 100 presents a listing of client records 102 . Using client tracking screen 100 , facility personnel can search for individual client records within listing 102 by, for example, last name, identification number, or date, and can access the individual client records. Using client tracking screen 100 , facility personnel may also access administrative information, behavior reports which may contain incident or observation reports, and turnstile logs that indicate data and time of facility access by individuals.
[0061] FIGS. 10 and 11 illustrate example client record screens 110 and 130 that may be presented by a display of a user interface 46 of an access system 42 of the client management system 50 . In exemplary embodiments, client record screens 110 and 130 display data stored within a record stored within database 20 for a client of a social services organization, e.g., data collected and generated during an intake process as described above with reference to FIG. 7 . As shown in FIG. 10 , client record screen 110 may include a photo 112 of a client, a client identification code 114 , and “main” information 116 for the client, such as the client's name and age. Client identification code 114 may correspond to a client identification code 34 generated during the intake process and printed on a front side of a client credential card 22 .
[0062] Client record screen 110 may also present personal information 118 such as gender, birth date, height, weight, eye color, hair color, complexion, ethnicity, and the like, and additional information 120 such as family contact information. Client records may be linked with family records within database 20 . For example, upon intake of a particular client, information also may be collected for children, a spouse or other dependents of the client. This information may be presented with information for the client.
[0063] In the example illustrated in FIG. 10 , client record screen 110 also provides a notification 122 regarding a level of access to facilities and/or services given to the client, and indicates dates and personnel associated with creation and modification of the client record.
[0064] Client record screen 130 illustrated in FIG. 11 displays the name and identification number 114 of the client, as well as additional, additional information 120 stored within the record for the client. For example, the illustrated client record screen 130 displays information identifying children of the client, a client management forms generated for the client, and a services rendered to the client. One or both of client record screens 110 and 130 may be accessed by selecting one of the clients listed on client tracking screen 100 of FIG. 9 . In some embodiments, a user accesses client record screen 130 by selection of additional information 120 within client record screen 110 .
[0065] FIG. 12 illustrates an example client facility access record screen 140 that may be presented by a display of a user interface 46 of an access system 42 of the client management system 50 . When a client who already has a record within database 20 and has previously been issued a card 22 attempts to access a facility for housing or other services, facility personnel may use access workstation 44 to create a facility access record reflecting admission of the client. As shown in FIG. 12 , client intake screen 140 may present information concerning date of intake, client name, data of birth, age, the name of facility personnel handling intake. Additional information such as emergency contacts, housing, education, income, employment, medical data, veteran status, and community collaboration may be presented. As described above, such information about clients may be entered into database 20 , where it will be stored, reviewed, modified or updated.
[0066] FIG. 13 is an example housing intake screen 145 presented by a display of a user interface 46 of an access system 42 of the client management system 50 . As shown in FIG. 13 , the housing intake screen 145 may present general information 147 such as intake date, client name, date of birth, age, and the name of facility personnel handling intake. Additional information may pertain to family, emergency contacts, housing, education, income, employment, veteran status, medical status, criminal status and the like.
[0067] Client information entered into a housing intake interface is used by housing module 56 of access workstation 44 to track application for and usage of housing by clients, and to identify housing opportunities at alternate facilities. Alternatively, client information may be used by housing module 56 to identify permanent or longer-term housing opportunities, such as low income or subsidized apartments and the like.
[0068] FIG. 14 is an example services screen 150 presented by a display of a user interface 46 of an access system 42 of the client management system 50 . As shown in FIG. 14 , the services screen 150 may include information similar to that presented in FIGS. 12 and 13 . As further illustrated in FIG. 14 , the services screen may present creation of case notes 152 or service records 154 . Case notes 152 may include miscellaneous information about a client. Service records 154 may provide a history of the services that a client has received. The history of services that a client receives may be queried by direct services module 58 to determine whether delivery of additional services is necessary or timely.
[0069] FIG. 15 illustrates an example behavioral report screen 155 that may be presented by a display of a user interface 46 of an access system 42 of the client management system 50 . Behavioral report screen 155 includes fields that allow facility personnel to enter report information 157 regarding incidents or observations for a particular client, including date, time, location, and description, which may be stored within database 20 as part of the record for the client. The incidents or observations may be entered by facility personnel concerning suspicious or questionable activity by a client. The incident or observation information may also be presented by incident/observation tracking module 54 , which may warn users of the client management system 50 to increase security in response to the incident or observation. In one embodiment, access is denied for the client based on incidents or observations recorded within database 20 .
[0070] FIG. 16 illustrates an example report generator screen 160 which may be presented by the client management system 50 . Report generator screen 160 may be presented by a display of a user interface 46 of an access system 42 . As shown in FIG. 16 , report generator screen 160 presents fields that can be selected by facility personnel to set a reporting module 60 of an access workstation 44 . When run, reporting module 60 of access workstation 44 filters information contained in database 20 and produces reports such as turnstile reports 162 detailing client access to the facility, and cost of services reports 164 . As described above, the reports generated by reporting module 60 may be used as evidence of compliance with regulations and as justification for funding.
[0071] FIG. 17 illustrates an example report screen 170 presented by the client management system 50 . Report screen 170 may be generated by a reporting module 60 of an access workstation 44 , and may be presented by a display of a user interface 46 of an access system 42 . In the example of FIG. 16 , the report screen presents a turnstile report including various details for clients admitted to a facility over a period of time. In particular, the statistics 172 shown in FIG. 17 include the sex and ethnicity of clients admitted to Dorothy Day from Jan. 1, 2003 to Jan. 4, 2003.
[0072] FIGS. 18-23 illustrate example client data intake screens presented by the client management system 50 . The intake screens may be presented by a display of a user interface 16 of an intake workstation 12 ( FIG. 1 ). The intake screens provide fields for entry of information by facility personnel during initial intake of a client into the client management system. The information entered may be used to create a record within database 20 and a card 22 for the client.
[0073] For example, FIG. 18 depicts client intake screen 180 which includes fields for entry of a variety of client information, such as main information 182 and personal information 184 that may be stored on an identification card and within a record for the client in database 20 . Child intake screen 190 of FIG. 19 includes fields for entry of information 192 relating to the children of a client, as well as client information 194 . Information relating to children of a client may be stored within database 20 as part of the record for the client, or within separate records that are associated with the record of the client.
[0074] Intake screen 200 of FIG. 20 illustrates a housing intake screen 200 , which includes fields for entry of information relating to the last permanent address for the client. In addition, FIG. 20 illustrates other residence information about a client, such as where the client resided over a particular period of time, where the client spent most of the last five years, and reasons that have to the client requiring shelter. Such information is stored within database 20 , and may be used by, for example, a housing module 56 for preparation of applications for long-term housing, or a reporting module 60 for generation of reports that provide detail regarding the types of clients serviced by the facility or organization.
[0075] Intake screen 210 depicted in FIG. 21 includes fields for entry of client education and employment information. For example, FIG. 21 depicts a field for income sources within a particular period of time. Such information is stored within database 20 , and may also be used by a housing module 56 for preparation of applications for long-term housing, a direct services module 58 for scheduling of employment related services, or a reporting module 60 for generation of reports that provide detail regarding the types of clients serviced by the facility or organization.
[0076] Intake screen 220 depicted in FIG. 22 includes fields for entry of client medical information. As shown, medical information may include medical conditions, mental health issues, and substance abuse issues. Such information is stored within the client record within database 20 , and may be used by, for example, a direct service module 58 of a client access workstation 44 to schedule appropriate services, such as provision of medication or counseling, based on the client's condition.
[0077] Exemplary intake screen 230 illustrated in FIG. 23 includes a field 232 for entry of client interests, and fields 234 for indicating services provided by the facility or organization that the client wishes to use. Such information may be used by a direct service module 58 of a client access workstation 44 to schedule the desired services.
[0078] Various embodiments of the invention have been described. For example, a client management system 50 and associated processes have been described. However, one skilled in the art will recognize that various modifications may be made to the described embodiments without departing from the scope of the invention.
[0079] For example, the invention may also be embodied in a computer-readable medium comprising instructions that cause a programmable processor to perform functions attributed to the components of a client management system herein. The computer-readable medium may comprise any magnetic, optical, or electrical media, such as a random access memory (RAM), read-only memory (ROM), CD-ROM, hard disk, electrically-erasable programmable ROM (EEPROM), flash memory, or the like.
[0080] As another example, a single device, such as a computer or workstation, may provide the functionality of both the intake workstation and the access workstation described herein. In such embodiments, access to intake functionality may be controlled by user name and password. Further, in some embodiments, varying degrees of access to the functionality provided by access workstations may be controlled by username and password. For example, access to the various modules 54 - 60 provided by an access workstation 44 may granted on a per-module basis.
[0081] Moreover, a client management system may include more than one network and more than one database. Further, a database may be stored within more than one memory, and managed by more than one device. In some embodiments, a client management system may include a web server, and the various screens described herein may be served to intake workstations 12 and access workstations 44 as web pages.
[0082] Although described herein as, in exemplary embodiments, being implemented via Lotus software applications and database platforms commercially available from International Business Machines Corp, the invention is not so limited. The invention may be realized through use of any suitable commercially available or custom-designed database platforms and software applications. These and other embodiments are within the scope of the following claims.
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The invention is directed to a client management system for social service organizations. The client management system provides a powerful, convenient, and easy-to-use system for management of client relationships within a social service organization. The client management system may be useful in a variety of social service organizations including, for example, homeless shelters, domestic violence support providers, state and country governments, information and referral agencies, and food shelves. The client management system may facilitate client intake, delivery of services, case management, data sharing among different organizations or facilities within a single organization, security monitoring, and custom reporting.
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CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 60/873,493, filed Dec. 7, 2006, which is hereby incorporated by reference herein in its entirety.
TECHNICAL FIELD
The disclosed subject matter relates to systems, methods, media, and means hiding network topology.
BACKGROUND
Digital devices often exchange messages to communicate with each other. These messages can contain not only the information meant to be communicated, but also other information such as routing information. In some cases, network topology information can be determined by examining, for example, routing information exchanged between digital devices. For example, when sending a message, a sender may insert routing information into the message and send the message to a receiver on a path that travels through various other devices. Some of these devices may add further routing information, such as their network addresses, to the routing information associated with the message. The receiver of the message can include the routing information in its response so that the response can be correctly routed back to the sender. However, network providers may wish to keep this routing information away from, for example, attackers, other networks, network subscribers, or any entity that does require access to the information.
One reason to keep network topology information private is that attackers can use this information to identify parts of a network for attack. For example, an attacker masquerading as a legitimate user may examine the headers of a packet it receives from a network to determine the address of a critical component of that network. The attacker may then directly target the critical component with an attack, such as, for example, a denial-of-service (DoS) attack. A network provider may also want to keep network topology information private for reasons other than attack avoidance. For example, an IP address read from a packet header may reveal that a network provider has contracted to use the equipment of another entity (e.g., a competitor, a sub contractor, etc.). However, the network provider may have preferred to keep this information confidential for business reasons.
One method that can be used to protect network routing information in packets is encryption. For example, a network component that sends a packet to a mobile device can encrypt topology information that is needed by the network for routing responses from mobile devices, but is not directly needed by the mobile devices. A mobile device can insert the encrypted topology information into its response to the network component. The network can then decrypt the encrypted topology information and use it as necessary. However, mere encryption of the header may still leave the network vulnerable. For example, topology information may be inadvertently or maliciously removed such that the packet lacks proper routing information. Alternatively, an encrypted header may be altered so that a response cannot be routed or is routed improperly. It is also possible that an attacker may be able to decrypt an encrypted header and thus access the header and its now unprotected topology information.
SUMMARY
Systems, methods, media, and means for hiding network topology are provided. In some embodiments, methods for hiding network topology are provided, the methods including: receiving a message including topology information from a sender; removing at least part of the topology information; associating the removed topology information with an identifier; saving the topology information; sending the message to a receiver; receiving a response from the receiver; retrieving the removed topology information based on the identifier; inserting the removed topology information into the response; and sending the response to the sender.
In some embodiments, computer-readable media storing computer-executable instructions that, when executed by a processor, cause the processor to perform methods for hiding network topology are provided, the methods including: receiving a message including topology information from a sender; removing at least part of the topology information; associating the removed topology information with an identifier; saving the topology information; sending the message to a receiver; receiving a response from the receiver; retrieving the removed topology information based on the identifier; inserting the removed topology information into the response; and sending the response to the sender.
In some embodiments, a intermediate apparatus in a network, including: a memory; an interface; and a processor in communication with the memory and the interface is provided, wherein the processor: receives a message including topology information from the interface; removes at least part of the topology information; associates the removed topology information with an identifier; saves the topology information in the memory; sends the message through the interface; receives a response from the interface; retrieves the removed topology information from the memory based on the identifier; inserts the removed topology information into the response; and sends the response to the through the interface.
In some embodiments, a wireless communication system is provided, including: means for receiving a message including topology information from a sender; means for removing at least part of the topology information; means for associating the removed topology information with an identifier; means for saving the topology information; means for sending the message to a receiver; means for receiving a response from the receiver; means for retrieving the removed topology information based on the identifier; means for inserting the removed topology information into the response; and means for sending the response to the sender.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified illustration of an IP Multimedia Subsystem (IMS) which can be used in accordance with some embodiments of the disclosed subject matter.
FIG. 2 is a simplified illustration of a Multimedia Domain (MMD) system which can be used in accordance with some embodiments of the disclosed subject matter.
FIG. 3 illustrates a control plane architecture for an IMS/MMD solution that can be used in accordance with some embodiments of the disclosed subject matter.
FIG. 4 illustrates a method for performing topology hiding in accordance with some embodiments of the disclosed subject matter.
FIG. 5 also illustrates a method for performing topology hiding in accordance with some embodiments of the disclosed subject matter.
DETAILED DESCRIPTION
Systems and methods for inhibiting access to network topology information are disclosed. Using some embodiments of the disclosed subject matter, an intermediate can remove topology information from an outgoing message and store the removed headers in, for example, a database, a memory, and/or a cache. When a response to the message is received at the intermediate, the topology information can be located and inserted into the response and the response can be forwarded to the sender of the message. Removal and reinsertion of topology information can be controlled by, for example, network policy settings. Some embodiments can provide removal and reinsertion of header information in some cases and encryption in others. This can allow, for example, a network operator to control who can address certain parts of a network and can allow different address realms to be used on an internal network and an external network.
Various embodiments of the disclosed subject matter can be used with various network types, protocols, standards, and/or topologies. For example, FIG. 1 illustrates an IP Multimedia Subsystem (IMS) 100 , which is a network architecture that can provide users with mobile and fixed multimedia services implemented as, for example, functions. A function can be implemented on a dedicated node, spread over multiple nodes, or can be implemented on the same node as other functions and/or applications. For example, these functions can be implemented on an ST16 Intelligent Mobile Gateway available from Starent Networks, Corp.
Some functions can be grouped into logical units. For example, a Call Session Control Function (CSCF) includes three functions: a Proxy-CSCF (P-CSCF) 101 , an Interrogating CSCF (I-CSCF) 102 , and a Serving CSCF (S-CSCF) 103 . A CSCF can manage much of the signaling that occurs in an IP IMS core. CSCF functions can be embodied in various forms and can be used with various network topologies and/or standards. For example, a CSCF can be use in both the Global System for Mobile Communications (GSM) standard and the Code Division Multiple Access (CDMA) 2000 standard. The 3rd Generation Partnership Project (3GPP) is responsible for IMS which works with GSM systems. The 3rd Generation Partnership Project 2 (3GPP2) is responsible for Multimedia Domain (MMD) which is used with CDMA systems and is based on the 3GPP IMS concept.
FIG. 1 also includes a Home Subscriber Server (HSS) 104 , a Subscriber Location Function (SLF) 105 , User Equipment (UE) 106 , Breakout Gateway Control Function (BGCF) 107 , Media Gateway Control Function (MGCF) 108 , Media Gateway (MGW) 109 , Public Switched Telephone Network (PSTN) 110 , Multimedia Resource Controller (MRFC) 111 , Multimedia Resource Function Processor (MRFP) 112 . The HSS 104 is a master user database that supports the S-CSCF or other network entities that handle calls and sessions. The HSS 104 stores subscription-related information such as user profiles, performs user authentication and authorization, and can provide information about the physical location of a user. When multiple HSS's are used in a network, an SLF 105 can be used to direct the queries to the HSS 104 storing the information. Legacy signaling networks may also use the HSS 104 for services. The MRFC 111 communicates with the S-CSCF and controls the MRFP 112 to implement media related functions. The combination of the MRFC 111 and MRFP 112 provides a source of media in the home network. The BGCF 107 is a server that can route based on telephone number and is used when calling to a phone on the circuit switched network. The MGCF 108 and MGW 109 are used to convert signaling from IMS to that which is appropriate for PSTN 110 circuit switched networks. The IP Multimedia Networks can include application servers and other network entities that provide services to User Equipment (UE). The UE can include, for example, a cell phone, a personal digital assistant (PDA), or a laptop computer.
FIG. 2 illustrates an MMD system 210 within a larger network 200 . The MMD system 210 includes many of the same functions as the IMS system 100 of FIG. 1 , but further includes an access gateway/foreign agent 201 to communicate with access networks 215 , as well as a home agent 202 to provide Mobile IP support to mobile stations (e.g., cell phone, PDA, laptop, etc.).
In the context of the IMS and MMD systems, a P-CSCF can be the initial interface between, for example, a mobile device and an IMS. A P-CSCF is typically located in a visited network or in a home network when the visited network is not IMS compliant. The P-CSCF acts as a Session Initiation Protocol (SIP) proxy and can forward messages from the user equipment or mobile station to the appropriate network entity and from a network entity to the user equipment/mobile station. The P-CSCF can inspect messages, provide SIP message compression/decompression using, for example, SIGComp, provide a security associate to the UE/MS, and generate charging data records (CDR) because it sits on the path of the signaling message. The P-CSCF can also include or communicate with a policy decision function (PDF) that authorizes media resources such as the provided quality of service (QoS), management of bandwidth, and provided access.
The I-CSCF is the contact point within a network for connections destined to a user of that network or a roaming user currently located within the network's service area. The I-CSCF assigns an S-CSCF to a user so that the user can communicate with the network. The I-CSCF's IP address can be published in a Domain Name System (DNS) so that remote servers can find it and use it as an entry point.
The S-CSCF performs the session control services for the, for example, UE/MS. This includes handling registration of the UE/MS, inspecting messages being routed through the S-CSCF, deciding which application server provides service, providing routing services such as sending messages to the chosen application server or to a PSTN, and enforcing the policies of a network for a given user. The S-CSCF can also communicate with the HSS to access user profiles and other information.
Application servers (e.g., 220 and 221 ) can host and execute services such as caller ID, call waiting, call holding, push-to-talk, call forwarding, call transfer, call blocking services, lawful interception, announcement services, conference call services, voicemail, location based services, and presence information. The application servers can interface with the S-CSCF using SIP and, depending on the service, can operate in an SIP proxy mode, an SIP user agent mode, or an SIP back-to-back user agent mode.
FIG. 3 illustrates a control plane architecture for an IMS/MMD solution that can be used in accordance with some embodiments. A session manager 310 services and processes user session data flow for user equipment(UE)/mobile subscribers(MS). The session manager 310 includes functional layers such as a system service layer 311 , a call processing layer 320 , and a call processing support services layer 313 . The system services layer 311 provides an interface for instructions to be passed to the session manager 310 and the other layers. A command line interface (CLI) 314 as well as network processing unit interface 315 can be included. The call processing layer includes a service broker/Service Control Interaction Manager (SCIM) 321 , a CSCF core 322 that includes an I-CSCF, an P-CSCF, and an S-CSCF, a unified message mapping interface 323 , applications 324 , and a SIP stack 325 . The call processing support services layer 313 includes a variety of services such as routing and address translation service, subscriber management service, changing interface service, media interface service, QoS policy interface service, security interface, and regulatory server interface.
Returning to the call processing layer 320 , this layer includes signaling protocols and call control using universal SIP as an application program interface (API). The signaling protocols can be, for example, SIP, ISUP, MGCP, or H. 323 . Further, the call processing layer 320 allows inter-working between SIP variants and other protocols through a unified messaging mapping (UMM) interface. The UMM interface can convert protocol specific messages and parameters to the universal SIP like API format. SIP like messaging is used, in some embodiments, because SIP has a large message set and can cover the possible messaging scenarios for SIP and other protocols.
SIP messages can include, for example, request messages such as, INVITE, CANCEL, BYE, and ACK. SIP message can also include, response messages, such as, for example, PRACK, MESSAGE, PUBLISH, REFER, UPDATE, and OPTIONS. SIP message headers can include, for example, Via, Record Route, Route Contact, To, and From. Network topology information can be contained in these headers and these headers can be removed and/or encrypted in some embodiments.
As illustrated in FIG. 4 , in some embodiments, a message can be received, at 400 , at an intermediate 405 , from, for example, a internal network component. The intermediate 405 , can be, for example, a network component at a network boundary, a CSCF, a P-CSCF, an I-CSCF, a proxy server, and/or an SMS proxy server. Topology hiding can be performed by removing information from a message, at 410 , and saving the information, at 420 . The message can be sent, at 430 , to a receiver 406 such as, for example, a UE/MS. The receiver can receive the message at 440 and send a response at 450 . When a response to the message is received, at 460 , the topology information can be retrieved, at 470 , and inserted into the response, at 480 . The receiver 406 can be, for example, a device outside of the network of intermediate 405 . For example, receiver 406 can be a mobile handset in communication with another device through an access network (e.g., Access Network 215 of FIG. 2 ).
The topology information can be saved, at 420 , in, for example, a database, a cache, RAM, or any appropriate memory. The information can be associated with, for example, a user identifier that can be used to retrieve the information, at 470 . The user identifier can be, for example, a public user ID. In some embodiments, the memory space where the information is stored can be reserved and/or allocated to be used for a specific call session and can be released and/or de-allocated when the session ends.
FIG. 5 shows another illustration of a method for performing topology hiding. A message 501 , for example, an SIP request such as an INVITE, can be sent, at 510 , from sender 500 . The message 501 can arrive at an intermediate 550 and have its topology information removed and stored, at 520 . The message 502 (message 501 without topology information) can be sent, at 530 , to a receiver 560 . Receiver 560 can send a response 503 , at 535 . The response 503 can be received at intermediate 550 and have its topology information retrieved and inserted, at 540 . The response 504 ( 503 with the topology information) can be sent, at 545 , to sender 500 . Intermediate 550 , can be, for example, a network component at a network boundary, a CSCF, a P-CSCF, an I-CSCF, a proxy server, and/or an SMS proxy server.
In some embodiments, intermediate 550 can decide to remove only some topology information from message 501 . For example, the address of sender 500 can be left in message 501 , but other topology information, for example, the addresses of devices that message 501 traveled through between sender 500 and intermediate 550 can be removed. This may be done, for example, if receiver 560 needs to know the address of sender 500 . Intermediate 550 can encrypt some topology information and remove other topology information from a message 500 . For example, in the previous example, the address of sender 500 can be encrypted. Some embodiments can also select between one of using encryption or removing topology information (e.g. headers) to perform topology hiding. Decisions of whether to and/or what to remove and/or encrypt from topology information can be based on various factors, such as, for example, the identity and/or location of receiver 560 , the identity and/or location of sender 500 , the identity and/or location of intermediate 550 , the type of topology information, the type of message 501 , and/or network policy settings (e.g., P-CSCF policy, I-CSCF policy, etc.). In addition, in some embodiments, topology hiding can be enabled or disabled using a command line interface (CLI)/event monitoring service (EMS).
Returning to system 100 of FIG. 1 , A P-CSCF 101 , according to some embodiments, can perform various tasks upon receiving a message. This message can be, for example, in UMM format and use UMM parameter. On receiving a REGISTER message, for example, a P-CSCF can insert a path header and insert a require header containing the option tag “path.” The P-CSCF can create a globally unique IMS charging identity (ICID), save it locally and insert it into the ICID parameter of the p-Charging-Vector header. If the security is supported, a P-CSCF can insert the integrity protected parameter with a “yes” value. Otherwise it can insert the integrity protected parameter with the a “no” value. A P-CSCF can insert a P-Visited-Network-ID header field with a pre-provisioned string that identifies the visited network in the home network. Even if the P-CSCF is local, this string can be inserted to be used for logging purposes.
On receiving 401 from S-CSCF a P-CSCF removes IK and CK values and sends a message to security interface for setting up the security association set up as a result of the challenge. If the security is enabled, a security server header can be inserted in the response. Once the positive response is received from security interface, the P-CSCF can send a returnResultSuccess to callLeg.
On receiving 200 OK response to register, a P-CSCF can check the expires header or expires parameter in contact. If it is non-zero then the service route headers for that public user identity can be stored. The security interface can be sent a message to setup the security association, if a new security association is needed. A message can be sent to the security interface to delete the old security association, if the new association is requested. A P-CSCF can return result success/failure to the callLeg to pass the response received from the security interface.
On receiving a request from UE P-CSCF a P-CSCF can match the service route header for that public user identity against the preloaded route header. If the match is not successful, a result error with a 400 response code can be returned to the callLeg. The P-CSCF's address can be added in the “via” header as configured in the service mode. The P-CSCF's Universal Resource Indicator (URI) can be added in the record route. The P-preferred-ID can removed and the P-Asserted-ID can be added. A globally unique ICID parameter can be created and inserted in the P-charging-Vector header. The result can be sent to the callLeg.
For responses, the P-CSCF can store the value received in the p-charging-function-address header and store the list of record route. The P-CSCF can also change the record route port number to the protected server port number as negotiated with UE during registration.
In some embodiments, a P-CSCF interacts with an IP Security (IPSEC) manager to set up security associations and interact with a policy interface to apply application policies. A P-CSCF can perform I-CSCF discovery in various ways. For example, a P-CSCF can use a configured list of I-CSCF defined by a peering server configuration. In other embodiments, a P-CSCF can perform I-CSCF discovery by using a DNS/Naming Authority Pointer (NAPTR).
IP address spoofing/IMS identity impersonation prevention is provided in certain embodiments. The P-CSCF can compare the IP address the request is received from and the subscriber's contact ip address to make sure the user who is registered is the one trying to make a call. The P-CSCF can also check the ip address allocated at the Packet Data Protocol (PDP) context creation with the IP address in the received SIP request to make sure the user who is paying for the IMS is using its own data access.
In some embodiments, the I-CSCF interfaces with HSS to validate visited network information sent by P-CSCF. If the subscriber is not allowed to roam in the visited network, the HSS sends an error indicating that roaming is not allowed. In certain embodiments, where the CSCF functionality is integrated into a Core CSCF module, the I-CSCF does not have to discover the S-CSCF based on the registering user and capabilities. In the second configuration when P-CSCF is separate I-CSCF is still integrated with S-CSCF therefore discovery is not required. External S-CSCF discovery can also be used by requesting an additional attribute from the HSS and selecting the S-CSCF based on the capabilities requested by the subscriber
Although the invention has been described and illustrated in the foregoing illustrative embodiments, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the details of implementation of the invention can be made without departing from the spirit and scope of the invention, which is limited only by the claims that follow. Features of the disclosed embodiments can be combined and rearranged in various ways within the scope and spirit of the invention.
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Systems, methods, media, and means for hiding network topology are provided. In some embodiments, methods for hiding network topology are provided, the methods including: receiving a message including topology information from a sender; removing at least part of the topology information; associating the removed topology information with an identifier; saving the topology information; sending the message to a receiver; receiving a response from the receiver; retrieving the removed topology information based on the identifier; inserting the removed topology information into the response; and sending the response to the sender.
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STATEMENT OF RELATED APPLICATIONS
[0001] This patent application claims priority on and the benefit of German Patent Application No. 10 2011 013 806.4 having a filing date of 14 Mar. 2011.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention relates to a method for washing in particular items of laundry, the items of laundry being at least washed with a treatment liquid in a rotationally drivable drum and the treatment liquid being removed from the drum as required by means of at least one outer drum assigned at least to part of the drum. Furthermore, the invention relates to an apparatus for washing in particular items of laundry, with a rotationally drivable drum and at least one stationary outer drum which extends at least over part of the length of the drum.
[0004] 2. Prior Art
[0005] The washing, namely the actual laundering and the rinsing, of all types of objects, in particular items of laundry, is undertaken in washing machines which have a rotationally driveable drum which is assigned at least one stationary and liquid-tight outer drum. The at least one outer drum extends over at least part of the drum, in particular part of the length of the rotationally driveable drum. The washing is undertaken using a treatment liquid, which optionally has treatment additives, in the drum. The treatment liquid takes up only a lower part of the drum. The level, i.e. the surface of the treatment liquid, preferably lies somewhat below the axis of rotation of the drum. Where the drum is assigned an outer drum, the treatment liquid is also located in the liquid-tight outer drum. By means of a perforation in the rotationally driveable drum in the region of the respective outer drum, the treatment liquid in the outer drum can enter the lower region of the rotating drum where the treatment liquid comes into contact with the objects to be washed, in particular items of laundry, which are located in the rotating drum.
[0006] As a consequence of the drum executing full circle rotations or opposed part circle rotations (pivoting movements) during the washing, foaming occurs, caused especially by the treatment additives in the treatment liquid. The foam accumulates with lint at least partially combined therewith from the laundry to be washed on the surface of the treatment liquid. In addition, the treatment liquid absorbs dirt washed out of the laundry and possibly foreign materials which, for the most part, are heavier than the treatment liquid and therefore collect in the bottom region of the outer drum. The foam and the dirt impair the efficacy of the washing operation.
BRIEF SUMMARY OF THE INVENTION
[0007] The invention is based on the object of providing a method and an apparatus for more effectively washing and/or rinsing items of laundry and other objects.
[0008] A method for achieving this object is a method for washing in particular items of laundry, the items of laundry being at least washed with a treatment liquid in a rotationally drivable drum and the treatment liquid being removed from the drum as required by means of at least one outer drum assigned at least to part of the drum, wherein, during at least the washing, the treatment liquid is filtered outside the drum and the at least one outer drum. According thereto, the treatment liquid, preferably always only some of the treatment liquid, is filtered during the treatment, i.e. in particular the washing and rinsing of the items of laundry or other objects, outside the drum and the at least one outer drum assigned thereto. Since the filtering is undertaken during the washing operation, attendant materials which impair the washing operation are successively removed from the treatment liquid. The washing can then be undertaken more effectively because of the lower loading of the treatment liquid by the attendant materials. The washing operation is not impaired by the filtering outside the washing machine.
[0009] The filtering of the treatment liquid is preferably undertaken continuously during the washing. As a result, attendant materials, in particular foam, lint, dirt residues and the like, which are newly collected in the treatment liquid as the washing operation proceeds are gradually filtered out, preferably continuously, in particular during the entire washing operation.
[0010] Provision is preferably made for the continuous filtering of the treatment liquid to be undertaken in a manner such that the treatment liquid is successively circulated by being pumped through or via the filter. As a result, some of the treatment liquid is always subjected to filtering while the rest, especially a large part, of the treatment liquid remains in the outer drum of the rotationally driveable drum and therefore, despite the successive and/or continuous filtering of some of the treatment liquid being undertaken at the same time, the washing operation is maintained without a loss in performance.
[0011] In an advantageous development of the invention, a continuous stream of the treatment liquid is let out of the outer drum at at least one outlet and, after filtering, said treatment liquid is returned again to the outer drum. As a result, a small part of the treatment liquid is constantly circulated past the filter and the filter is continuously subjected to treatment liquid to be filtered. The volumetric stream of treatment liquid which is conducted via the filter is selected so as to correspond to the efficiency of the filter and the amount of treatment liquid remaining in the outer drum and in the drum containing the laundry to be treated is not significantly reduced, and therefore the level of the treatment liquid in the drum does not fall below the desired level.
[0012] According to a preferred development of the method, lighter and heavier constituents are optionally, in particular alternately, filtered out of the treatment liquid. Therefore, constituents, such as foam, lint or the like, collecting on the surface of the treatment liquid and heavier constituents, such as dirt particles, foreign materials or the like, dropping onto the bottom of the outer drum can be gradually filtered out from the treatment liquid. It is alternatively also conceivable simultaneously to remove a mixture of treatment liquid containing lighter constituents and heavier constituents from the outer drum and to filter said constituents together.
[0013] Preferably, in order to filter out lighter constituents from the treatment liquid, the treatment liquid, with the lighter constituents in the region of the surface thereof, specifically on the surface or just below the surface, is removed from the outer drum while the treatment liquid, with the heavier constituents below the surface of the treatment liquid, especially on the bottom or in the region of the bottom of the outer drum, is removed from same. By means of the various options for removing the treatment liquid to be filtered from the outer drum, the filter has a plurality of functions by being able to filter out lighter and heavier constituents, in each case separately or else together, from the treatment liquid.
[0014] Provision is preferably made also to use the at least one filter in order to filter treatment liquid to be let out of the outer drum at the end of the washing operation. This provides a further option for using the same filter. The treatment liquid to be let out of the outer drum can also be completely filtered by filtering outside the outer drum. The filtered treatment liquid is preferably conducted into a storage tank. The filtered and used treatment liquid can be supplied from the collecting or storage tank for suitable reuse.
[0015] According to a further preferred refinement of the method, the treatment liquid is filtered by a gravity filter. The treatment liquid can thus flow freely through the filter, wherein the filtered treatment liquid is separated from the filtered-out constituents by gravity. As an alternative or in addition, provision may be made to allow the liquid to flow in a freely flowing manner by means of gravity to the filter. The filter is thereby uniformly subjected to the treatment liquid following the gravity action and the filtering is likewise undertaken. In this case, however, it is conceivable for the flow rate or the amount of treatment liquid supplied to the filter per unit of time to be able to be set or changed by, for example, an adjustable throttle valve in a feed line to the filter. The treatment liquid supplied to the filter per unit of time can thus be matched to the efficiency of the filter and optimum filtering thus brought about.
[0016] An apparatus for achieving the object referred to at the beginning, the apparatus preferably being a washing machine, is an apparatus for washing in particular items of laundry, with a rotationally drivable drum and at least one stationary outer drum which extends at least over part of the length of the drum, wherein a circulating line having at least one filter is assigned to at least one outer drum. Owing to the fact that a circulating line having a filter is assigned to at least one outer drum, the treatment liquid can be filtered, specifically in particular continuously, during the washing operation, namely the pre-washing, clear washing and/or rinsing. As a result, treatment liquid which is at least partially freed from constituents impairing the washing operation, especially foam, is always available for the washing operation.
[0017] The circulating line is preferably provided with a plurality of outflows, in particular outflows which can be shut off individually, from the respective outer drum. In this case, an upper outflow is in particular arranged in the region of the level of the treatment liquid in the drum and in the outer drum while another outflow is preferably provided in the region of the bottom or in the bottom of the outer drum. This enables both treatment liquid with attendant materials swimming thereon in the region of the surface of the treatment liquid and also treatment liquid with dropping attendant materials to be removed from the outer drum. The capability of shutting off at least one outflow makes it possible to remove treatment liquid from the outer drum selectively from the top or from the bottom or, if desired, also to remove treatment liquid with floating and dropped attendant materials at the same time from the outer drum.
[0018] Another advantageous refinement of the apparatus makes provision to provide at least one pump in the circulating or circulation line downstream of the at least one filter, preferably as seen in the direction of flow of the treatment liquid. By means of the pump, the filtered liquid can be pumped back into preferably the same outer drum from which the treatment liquid was removed, optionally also a different outer drum, even if the position of the introduction of the filtered liquid into the outer drum is located higher than the filter.
[0019] Provision may be made for the circulating line to be connected, preferably downstream of the pump, to an inflow, which can be preferably shut off, to the outer drum. The capability of shutting off the inflow makes it possible to pump filtered treatment liquid to a different location. For example, the circulating line can have an outflow, to which at least one collecting tank is preferably assigned. The outflow may be located upstream of the pump, as seen in the direction of flow, if the filtered treatment liquid can be conducted away by gravity. By contrast, it is expedient to arrange the outflow downstream of the pump in the direction of flow if the filtered treatment liquid has to be pumped to the outflow located higher.
[0020] In a preferred apparatus, the at least one filter is designed as a gravity filter. This filter operates automatically. Above all, the treatment liquid to be filtered does not need to be pumped through the gravity filter by a pump. On the contrary, the treatment liquid can flow automatically on account of the potential energy thereof out of the outer drum to the filter and through or via the latter. A filter of this type may be designed as a sieve, through the opening in which the treatment liquid to be filtered flows, but heavier and lighter attendant materials are retained, and therefore said attendant materials can be removed on the filtering surface which is formed by the sieve and can have a rectilinear, oblique and/or curved profile.
[0021] In order to clean the filtering surface, in particular the filter sieve, said filtering surface can be subjected to a flowing fluid, for example by means of spray nozzles under the preferably sieve-like filtering surface.
[0022] The invention is suitable particularly for apparatuses designed in the manner of commercial washing machines, namely what are referred to as continuous process washing machines. A washing machine of this type has an elongate, overall rotationally driveable drum with a plurality of consecutive chambers, at least one of the chambers being assigned an outer drum. An outer drum is customarily located where treatment liquid, such as pre-washing liquid, clear washing liquid and/or rinsing liquid, can be conducted out of the drum or liquids can be supplied to the drum. By means of the assignment of the outer drum to at least one chamber, the invention makes it possible, in a chamber-related manner in a continuous process washing machine, always preferably to continuously filter only the treatment liquid present in the relevant chamber during the washing operation, specifically in particular to at least partially remove both lighter constituents and also heavy constituents successively, but constantly, especially continuously, from the treatment liquid in the relevant chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] A preferred exemplary embodiment of the invention is explained in more detail below with reference to the drawing, in which:
[0024] FIG. 1 shows a schematic side view of an apparatus according to the invention in the form of a continuous process washing machine.
[0025] FIG. 2 shows a cross section through a chamber, which is provided with an outer drum, of the continuous process washing machine from FIG. 1 in a schematic illustration.
[0026] FIG. 3 shows a cross section analogously to FIG. 2 in a different manner of operation.
[0027] FIG. 4 shows a cross section analogously to FIG. 2 in yet another manner of operation.
[0028] FIG. 5 shows a longitudinal section through a filter merely illustrated schematically in FIGS. 1 to 4 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0029] The invention is described below with reference to an apparatus, in the form of a continuous process washing machine 10 , for washing and rinsing items of laundry. However, the invention is not restricted thereto.
[0030] The continuous process washing machine 10 shown schematically in FIG. 1 has a cylindrical drum 12 which is rotationally driveable about a preferably horizontal axis of rotation 11 . The axis of rotation 11 lies on the longitudinal center axis of the drum 12 . The laundry to be washed is transported from the left to the right (with respect to FIG. 1 ) in the treatment direction 13 through the rotationally driven drum 12 .
[0031] A plurality of chambers 15 which are consecutive in the treatment direction 13 are formed by transversely directed partitions 14 in the drum 12 . One laundry batch is treated, in particular washed and rinsed, in each chamber 15 . The chambers 15 may be identical in size, but may also differ in size. The partitions 14 have central or eccentric openings (located at the edge) which are not shown in the figure. Through the openings, the laundry can be transferred batchwise in the treatment direction 13 from one chamber 15 into the following chamber 15 . The continuous process washing machine 10 shown in FIG. 1 has twelve chambers 15 . However, the invention is not restricted thereto. The continuous process washing machine 10 may have a larger or smaller number of chambers 15 .
[0032] The first four chambers 15 , as seen in the treatment direction 13 , form a pre-washing zone 16 in the continuous process washing machine 10 shown. The following five chambers 15 form a clear washing zone 17 . A rinsing zone 18 having three consecutive chambers 15 follows the clear washing zone 17 , as seen in the treatment direction 13 . The pre-washing zone 16 , clear washing zone 17 and rinsing zone 18 may have a number of chambers 15 differing from the exemplary embodiment (shown in FIG. 1 ) of the continuous process washing machine 10 . It is also conceivable for at least one further chamber (not illustrated in FIG. 1 ) to follow the rinsing zone 18 in order to form a finishing zone. The rinsing zone 18 may also be omitted.
[0033] In the continuous process washing machine 10 shown here, the final chamber 15 of the pre-washing zone 16 , the clear washing zone 17 and the rinsing zone 18 has in each case an outer drum 19 . In addition, an outer drum 19 is assigned to the first chamber 15 of the clear washing zone 17 and the rinsing zone 18 . All of the outer drums 19 are designed to be equally impermeable to liquid. So that treatment liquid for the laundry in the outer drum 19 can communicate with that section of the drum 12 which extends over the relevant chamber 15 with an outer drum 19 , the drum 12 is designed to be at least partially permeable for treatment liquid, in particular is perforated, in regions of those chambers 15 which are assigned an outer drum 19 . As a result, treatment liquid can enter the liquid-permeable section of the drum 12 , which section is assigned to the chamber 15 , from the respective outer drum 19 , and vice versa. The treatment liquid in the respective chamber 15 has a desired level. The level is preferably somewhat below the axis of rotation 11 ( FIGS. 2 and 3 ). Consequently, the surface of the treatment liquid in the relevant chamber 15 is also located somewhat below the axis of rotation 11 .
[0034] The lower region of each of the outer drums 19 of identical design preferably has an expanded portion preferably designed in the manner of a terminal box. Said expanded portion accommodates a stock of treatment liquid below the drum 12 .
[0035] Constituents which are lighter than the treatment liquid, for example foam, lint and the like, collect on the surface of the treatment liquid. The lint is preferably at least for the most part combined in the foam. Solid constituents of the treatment liquid that are heavier than the treatment liquid can collect on a bottom 20 of the outer drum 19 , which is expanded at the bottom in order to form the terminal box. The heavier constituents are dirt and other solids washed out of the laundry, for example small foreign bodies which can pass through the perforation in the drum 12 in the region of the respective chamber 15 with the outer drum 19 .
[0036] In the case of the continuous process washing machine 10 shown here, the outer drum of the final chamber of the clear washing zone 17 and the outer drum 19 of the final chamber 15 of the rinsing zone 18 are each assigned a circulating line 21 with a filter 22 . The latter are of identical design at the end of the clear washing zone 17 and at the end of the rinsing zone 18 . Both the circulating line 21 and the respective filter 22 are located outside the drum 12 and the outer drum 19 . The respective filter 22 and the circulating line 21 assigned thereto are preferably assigned, in particular fastened, to a rack 23 of the continuous process washing machine 10 . However, the filters 22 may also be located at a different location in the laundry away from the continuous process washing machine 10 . A pump 24 is provided downstream of the or each filter 22 , as seen in the direction of flow of the treatment liquid through the circulating line 21 , in order to pump the filtered treatment liquid back into the respective outer drum 19 .
[0037] FIGS. 2 to 5 show in more detail the circulating line 21 and the filter 22 assigned thereto in the region of the final chamber 15 of the clear washing zone 17 . The circulating line 21 and the filter 22 in the region of the outer drum 19 of the final chamber 15 of the rinsing zone 18 are designed in the same manner.
[0038] In particular, FIG. 2 shows that the circulating line 21 is divided, namely consists of a starting part, as seen in the direction of flow to the filter 22 , and a return part emerging from the filter 22 . As a result, the circulating line 21 is interrupted in the region of the filter 22 , but the starting part and the return part of the circulating line 21 are connected in terms of flow by the filter 22 . In addition, the starting part of the circulating line 21 is designed in two strands, namely has a first starting part 25 and a second starting part 26 . The first starting part 25 of the circulating line 21 is connected to an outflow 27 of the outer drum 19 , the outflow being located in the region of the level or the surface of the treatment liquid in the chamber 15 to which the outer drum 19 is assigned. The second starting part 26 of the circulating line 21 is connected to a second outflow 28 in the bottom region, in particular in the vicinity of the bottom 20 , of the outer drum 19 of the final chamber 15 of the clear washing zone 17 . The outflow 28 may also be provided in the bottom 20 of the outer drum 19 . Both starting parts 25 and 26 end upstream of the filter 22 . The return part of the circulating line 21 is assigned to that side of the filter 22 on which the filtered treatment liquid is obtained. The filtered liquid is pumped back into the outer drum 19 by the pump 24 in the return part of the circulating line 21 . For this purpose, an inlet 29 is provided for connecting a rear end of the return part of the circulating line 21 to the outer drum 19 below the surface of the treatment liquid.
[0039] A discharge line 30 branches off from the return part of the circulating line 21 downstream of the pump 24 , the discharge line leading to a collecting tank 31 or opening into the collecting tank 31 .
[0040] The second starting part 26 of the circulating line 21 is assigned a valve 32 . This is preferably an adjustable throttle valve with which the flow rate of the treatment liquid through the second starting part 26 can be changed, but the second starting part 26 may also be closed. In this way, the inflow of treatment liquid from the bottom region of the outer drum 19 to the filter 22 can be entirely prevented or changed in respect of the volumetric stream of the treatment liquid to the filter 22 per unit of time, for example for adaptation to the capacity of the filter 22 . Similarly, if required, a simple shut-off valve or an adjustable throttle valve may be arranged in the first starting part 25 of the circulating line 21 . It is then possible for partial streams from the surface of the treatment liquid and from the bottom of the outer drum 19 to be conducted in a directed manner to the filter 22 at the same time and for the flow rate of the treatment liquid through the first starting part 25 to be changed and optionally for the first starting part 25 of the circulating line 21 also to be completely closed. A further valve 33 is located in the return part of the circulating line 21 , specifically downstream of the branching off of the discharge line 30 form the circulating line 21 , as seen in the direction of flow of the treatment liquid. A valve 34 is also assigned to the discharge line 30 . By means of the valves 33 and 34 , the outflow of the filtered treatment liquid can be controlled in a directed manner, specifically either back to the outer drum 19 or into the collecting tank 31 .
[0041] The filter 22 is illustrated in detail in FIG. 5 . This involves what is referred to as a gravity filter, in which the treatment liquid to be filtered is caused by gravity to flow through a filter sieve 31 , specifically from the upper side of the filter sieve 48 to the lower side thereof. This may also be undertaken during the flow of the treatment liquid to be filtered along on the filter sieve 48 . The filter sieve 48 is arranged in a preferably completely closed housing 35 . The upper side of the housing 35 may optionally be open. The housing 35 has (as seen from the side) an oblique profile with an oblique bottom 36 . From above, the ends of the two starting parts 25 and 26 of the circulating line 21 are guided at the highest point into the oblique housing 35 . The filter sieve 48 is likewise fastened in an obliquely directed manner in the housing 35 at a distance from the bottom 36 . As a result, the filter sieve 48 divides the housing 35 into an upper part 37 located above the surface of the filter sieve 34 and a lower part 38 located below the filter sieve 48 . The filter sieve 48 may be formed from a perforated sheet with a uniform grid of passage holes of corresponding size or from a wire cloth with a corresponding mesh width.
[0042] The filter sieve 48 is preferably designed in two layers. Said filter sieve 48 consists of a lower, stable and large-meshed supporting lattice and a fine-meshed sieve which is arranged above the latter and is designed in the manner of a lattice or is braided. The optionally flexible sieve is then supported by the supporting lattice.
[0043] The filter sieve 48 ends at a distance upstream of a transverse wall 39 at the lower end of the housing 35 . A height-adjustable, transversely directed weir 40 is located upstream of the end of the filter sieve 37 . By appropriate height adjustment of the plate-like weir 40 a gap of corresponding width for conducting away the constituents filtered out of the treatment liquid is produced above the end of the lint sieve 34 . A pivotable flap may also be provided instead of the height-adjustable weir 40 . A chamber 42 for collecting the constituents filtered out of the treatment liquid is located between that end of the filter sieve 48 which is spaced apart from the transverse wall 39 and is formed by a lower transverse edge 41 of same. A collecting container 43 for filtered-out constituents can be provided in the chamber 42 . The collecting container 43 can preferably be removed from the chamber 42 or can be withdrawn from the chamber 42 in the manner of a drawer.
[0044] At the bottom end region upstream of the transverse wall 39 , the bottom 36 of the housing 35 has a depression which forms a sump 44 . During the emptying of the filter 22 , the remaining filtered treatment liquid collects in the sump 44 as the lowermost point of the housing 35 . In addition, the sump 44 forms a pump reservoir which ensures that, during operation of the filter 22 , the pump 24 is constantly supplied with sufficiently filtered treatment liquid. In addition, a float switch 45 serving to prevent dry operation of the pump 24 is provided in the sump 44 . Furthermore, a closable outflow 46 is located at the lowermost point of the sump 44 . When the outflow 46 is opened, the treatment liquid can be completely let out of the housing 35 of the filter 22 .
[0045] A plurality of cleaning nozzles 47 directed toward the lower side of the filter sieve 48 are provided in the lower part 38 of the housing 35 . The cleaning nozzles 47 are distributed in the lower part 38 in such a manner that they can subject the entire lower side of the filter sieve 48 , or at least a large part thereof, to cleaning liquid. The cleaning liquid is preferably fresh water. However, filtered treatment liquid from the collecting tank 31 may also be used. The used cleaning liquid is then pumped back again into the collecting tank 31 through the return part of the circulating line 21 and the discharge line 30 or conducted into an outflow.
[0046] The method according to the invention is described in more detail below with reference to the previously described apparatus, namely the continuous process washing machine 10 .
[0047] The method according to the invention makes provision, on the basis of the respective chamber 15 with an outer drum 19 , to preferably continuously filter the treatment liquid outside the outer drum 19 during the washing operation. The treatment liquid from each outer drum 19 or else only selected outer drums 19 or from only one outer drum 19 can be filtered. The filtration can be undertaken periodically during the washing operation, but also continuously during the entire washing operation. With the filtration during the washing operation, a small amount of the treatment liquid, which is continuously removed from the treatment liquid, is pumped through the circulating line 21 by the pump 24 and, in the process, is filtered by the filter 22 , which is designed as a gravity filter, in accordance with the principle of gravity. Only such a small part of the treatment liquid at a time is subjected to the filtering that the provided treatment liquid level in the drum 12 receiving the items of laundry to be washed and in the outer drum 19 is maintained. In the exemplary embodiment shown, the level of the treatment liquid in the drum 12 is selected such that the surface 49 of the treatment liquid lies somewhat below the axis of rotation 11 of the drum 12 ( FIGS. 2 to 4 ).
[0048] The flow rate of the treatment liquid through the circulating line 21 is selected or set at the throttleable valve 32 in such a manner that, over the course of a treatment operation of the batch of laundry in the relevant chamber 15 , the treatment liquid in said chamber 15 is completely circulated at least once and filtered by the filter 22 .
[0049] The method according to the invention is designed in such a manner that it permits a multiple function of the filter 22 . Accordingly, the filter 22 is used in order to carry out different filtering tasks which are illustrated schematically in FIGS. 2 to 4 .
[0050] FIG. 2 shows the use of the filter 22 for removing those constituents from the treatment liquid that are lighter than the treatment liquid, for example foam, in particular foam together with entrained lint. The possibly lint-containing foam collects on the surface 49 of the treatment liquid in the drum 12 . Via the outflow 27 , which is located in the region of the surface 49 of the treatment liquid, the foam containing lint and other lighter constituents is removed together with the treatment liquid located on the surface 49 from the drum 12 and the outer drum 19 and fed to the filter 22 via the first starting part 25 of the circulating line 21 . In the process, the treatment liquid with the lighter components passes into the upper part 37 of the housing 35 of the filter 22 . As a result of the oblique position of the filter sieve 48 , the treatment liquid to be filtered flows together with the lighter constituents to be filtered out along the filter sieve 48 . By means of gravity, only the treatment liquid passes through the filter sieve 48 , and said treatment liquid thus passes filtered into the lower part 38 of the housing 35 of the filter 22 . The filtered treatment liquid is then pumped by the pump 24 through the circulating line 21 , with the valve 33 open, to the inlet 29 in the outer drum 19 and therefore the filtered treatment liquid is supplied again to the washing process, namely to the outer drum 19 and the drum 12 .
[0051] The filtered-out lighter constituents of the treatment liquid flow along the oblique filter sieve 48 . Through the gap below the transverse edge 41 of the weir 40 , said filtered-out lighter constituents, in particular foam and lint, enter the collecting container 43 of the filter 22 . The collecting container 43 collects lint, in particular, which can be disposed of from time to time by the collecting container 43 being withdrawn or removed from the chamber 42 of the housing 35 of the filter 22 . Other constituents can be collected at another point of the chamber 42 and removed from there, for example into an outflow.
[0052] The valves 32 and 34 are closed during the previously described filtering off of lighter constituents from or out of the treatment liquid. Only light constituents are then separated from the treatment liquid, and the filtered treatment liquid is continuously pumped back circulating through the circulating line 21 into the continuous process washing machine 10 . As a result, cleaned treatment liquid is continuously supplied again to the treatment liquid, and therefore the quantity of treatment liquid in the relevant chamber 15 always remains substantially the same and is reduced only by the treatment liquid located in the circulating line 21 and in the region of the filter 22 . By means of the filtering off of foam, which is undertaken during the washing operation, with light constituents combined thereon or therein, the foam carpet on the treatment liquid is reduced and the washing action thereby increased, as a result of which stains especially can be more effectively removed from the laundry. It is also conceivable to temporarily close the weir 40 or the pivotable flap for certain time intervals during the filtering out of the foam with the light constituents combined therein and to subject the foam in the region of the filter 22 to water, preferably fresh water. As a result, the foam is destroyed, as it were, and the quantity of foam reduced.
[0053] FIG. 3 schematically illustrates a second intended use of the filter 22 . Here, the valve 32 in the second starting part 26 of the circulating line 21 is opened or adjusted to such an extent that the treatment liquid can be supplied continuously to the filter 22 during the washing of the laundry. In this case, the valve 32 , which is preferably designed as a throttle valve, is adjusted in such a manner that only a desired volumetric stream of the treatment liquid flows through the circulating line 21 . The treatment liquid enters the second starting part 26 through the outflow 28 arranged in the vicinity of the bottom 20 of the outer drum 19 . In this case, with the treatment liquid, heavier constituents thereof, for example dirt particles removed form the laundry, but also other small solid particles and possibly foreign bodies, pass via the outflow 28 and the second starting part 26 of the circulating line 21 to the filter 22 . The solid constituents are filtered out here from the treatment liquid by gravity by the solid constituents being retained by the filter sieve 48 and only the treatment liquid flowing through the filter sieve 48 and, in the process, being filtered. The filtered treatment liquid is pumped back again via the circulating line 21 through the inlet 29 into the outer drum 19 . Filtered-out solid constituents are removed laterally above the filter sieve 48 as a result of the oblique arrangement of same and are collected in the chamber 42 of the housing 35 of the filter 22 . Like lint, the solid constituents can also be collected in the collecting container 43 .
[0054] In the exemplary embodiment shown, the first starting part 25 of the circulating line 21 cannot be shut off by a valve. Constituents floating on the surface 49 of the treatment liquid are therefore continuously conducted through the first starting part 25 of the circulating line 21 to the filter 22 . By contrast, only treatment liquid with heavier constituents contained therein, if this is desired, flows through the second starting part 26 of the circulating line 21 as a result of the valve 32 which is assigned to said circulating line and can be shut off and throttled. For example, the valve 32 may be opened only periodically during the washing. However, the valve 32 may also be opened continuously, the throttle allowing only as much treatment liquid to be guided through the second starting part 26 to the filter 22 as the filter capacity permits. However, it is also conceivable likewise to assign a valve to the first starting part 25 of the circulating line 21 . If said valve is closed, with the valve 25 in the second starting part 26 open, only treatment liquid with heavier constituents contained therein can be supplied to the filter 22 and the treatment liquid freed from heavier constituents by said filter.
[0055] FIG. 4 shows the method according to a third manner of operation of the filter 22 . The treatment liquid is filtered here when the treatment liquid is completely let out of the chamber 15 . This is the case when a bath change, i.e. an exchange of the treatment liquid, is undertaken in the relevant chamber 15 . Such a bath change is preferably undertaken after the washing of the items of laundry in the relevant chamber 15 when the laundry batch is transferred from the chamber 15 into the next chamber 15 in the treatment direction 13 , for example the first chamber 15 of the rinsing zone 18 , or in order to unload the completely washed and rinsed laundry batch from the continuous process washing machine 10 .
[0056] When the treatment liquid is let out, the valve 32 in the second starting part 26 of the circulating line 21 and a possible valve in the first starting part 25 are preferably fully open. The treatment liquid can then be entirely let out of the drum 12 and out of the outer drum 19 assigned to the latter. The treatment liquid to be let out is filtered by the filter 22 and the filtered treatment liquid is subsequently conducted by the pump 24 through the circulating line 21 , with the valve 34 in the discharge line 30 open, into the collecting tank 31 . The following valve 33 in the circulating line 21 in the direction of flow of the treatment liquid through the circulating line 21 to the discharge line 30 is then preferably closed.
[0057] The lower sump 44 in the housing 35 of the filter 22 makes it possible to conduct the treatment liquid out of the filter 22 through the outflow 46 without leaving a residue. However, only the remaining treatment liquid collecting at the bottom in the sump 44 and being unable to be pumped by the pump 24 into the collecting tank 31 leaves the outflow 46 . As a consequence of the complete emptying not only of the outer drum 19 but also of the filter 22 , mixing of the treatment liquid of the washing operation which has taken place last with possibly different treatment liquid for the next washing operation is avoided.
[0058] If the treatment liquid is completely let out of the drum 12 and the outer drum 19 , cleaning of the filter sieve 48 preferably takes place with the filter 22 currently not carrying out any filtering. This is undertaken from the lower side of the filter sieve 48 by means of the cleaning nozzles 47 which are directed at said lower side. For this purpose, the cleaning nozzles 47 can be supplied with fresh water or cleaned treatment liquid from the collecting tank 31 as the cleaning liquid. The soiled cleaning liquid obtained during the cleaning of the filter sieve 48 is conducted away below the filter sieve 48 , i.e. in the lower part 38 . The cleaning liquid collects in the sump 44 at the lowermost point of the housing 35 of the filter 22 and is completely conducted away therefrom through the outflow 46 and subsequently disposed of. The filter 22 may also be cleaned in order to destroy the foam or reduce the quantity thereof during the manner of operation of the filter 22 according to FIG. 2 .
[0059] The method operates in the above-described manner both in the region of the final chamber 15 of the clear washing zone 17 and of the final chamber 15 of the rinsing zone 18 . It is optionally also possible for the method to be carried out at the final chamber 15 of the pre-washing zone 16 . The above-described method is also suitable for continuous process washing machines which only have a pre-washing zone 16 and a clear washing zone 17 , but not a rinsing zone 18 .
[0060] The invention is suitable not only for all types of continuous process washing machines but also for other washing machines and washing machines for washing and cleaning any other objects, i.e. not only items of laundry.
LIST OF REFERENCE NUMBERS
[0000]
10 Continuous process washing machine
11 Axis of rotation
12 Drum
13 Treatment direction
14 Partition
15 Chamber
16 Pre-washing zone
17 Clear washing zone
18 Rinsing zone
19 Outer drum
20 Bottom
21 Circulating line
22 Filter
23 Rack
24 Pump
25 First starting part
26 Second starting part
27 Outflow
28 Outflow
29 Inlet
30 Discharge line
31 Collecting tank
32 Valve
33 Valve
34 Valve
35 Housing
36 Bottom
37 Upper part
38 Lower part
39 Transverse wall
40 Weir
41 Transverse edge
42 Chamber
43 Collecting container
44 Sump
45 Float switch
46 Outflow
47 Cleaning nozzle
48 Filter sieve
49 Surface
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A method and apparatus for washing items of laundry that makes provision to continuously filter the treatment liquid during the washing operation. As a result, interfering attendant materials in and on the treatment liquid are successively removed during the washing operation, which increases the efficacy of the washing operation. Provision is preferably made to remove both lighter constituents, such as foam and lint, from the treatment liquid and also to filter heavier constituents, such as impurities washed out of the items of laundry, from the treatment liquid using the same filter. The same filter can also be used, after the end of the washing operation, to filter the treatment liquid to be let out and to temporarily store the treatment liquid in a collecting tank before the filtered treatment liquid is reused. The invention thus permits multiple functions of the filter.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of my U.S. Provisional Patent Application No. 60/860,553, titled Limited Life Medium, filed Nov. 22, 2006, which is incorporated herein by reference in its entirety.
The present application is related to my co-pending U.S. Patent Application No. 60/860,615, titled Limited Installation Medium, filed Nov. 22, 2006, and U.S. Patent Application No. 60/860,567, titled Limited Life Medium, filed Nov. 21, 2006, which are incorporated herein by reference in their entirety, and to commonly invented and assigned U.S. Patent Application Publication No. 2005/0195728, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The invention relates to media used to distribute information, and especially to such a medium that is intended to become unusable within a short period after the medium is first used or activated.
BACKGROUND
It is well known to distribute information, for example, music or motion pictures, on a disc or other portable medium. The medium may be either rented or sold to a member of the public who wishes to listen to or view the content of the medium. Sale prices are higher than rental fees, because a purchaser who retains permanent possession of a copy of the content gains greater benefit than a renter who has the medium with the content for only a short time. In order to prevent users from improperly exploiting the price difference, rental stores take steps to ensure that copies of the medium are returned at the end of the rental period. However, these returns are expensive for the store and inconvenient for the customer.
In order to eliminate the administrative cost and inconvenience of rental returns, it has previously been proposed to provide a storage medium that becomes unusable within a short period after the medium is removed from its packaging or after the medium is first read. For rental of motion pictures, a period of a few hours to a few days is typically appropriate.
Examples of previously-proposed limited life media are described in commonly invented U.S. Pat. No. 6,468,619, and U.S. Patent Application Publication No. 2005/0195728, and in U.S. Pat. No. 6,100,772.
With all of these devices, either reading the storage medium or some step preliminary to such reading, such as removing the storage medium from a container, initiates a process that renders the storage medium unusable. In many of these previously proposed devices, the agent that limits the life of the medium is a liquid, such as a solution of a mild acid or other corrosive agent in water, and the process of rendering the medium unusable is initiated by moving the solution from a storage location within the medium to an active location at which the liquid is in contact with a part of the storage medium that actually carries data.
U.S. Patent Application Publication No. 2005/0195728 proposes an optical disc that self-destructs within a predetermined period after the disc is first read. The disc described in U.S. Patent Application Publication No. 2005/0195728 contains a reservoir of solvent near its center. The process of reading the disc involves rotating the disc at high speed. Centrifugal force from the rotation redistributes the solvent to a location where the solvent destroys part of the data storage layer. The disc of U.S. Patent Application Publication No. 2005/0195728 is well suited to discs of the CD or DVD type, in which the data storage layer is a thin metal foil, susceptible to destruction by mild acids, and in which the inner edge of the data storage layer carries a vital control track. By suitable selection of the strength of the acid, the time within which the disc becomes unusable can be selected in a range from minutes to days.
In the interests of economy and reliability, a simple design of the mechanism for moving the solution to the active location is desirable. The mechanism of U.S. Patent Application Publication No. 2005/0195728 is especially simple. That mechanism has no moving parts, and is operated solely by the liquid flowing under the action of centrifugal force when the disc rotates. However, where a liquid flowing under centrifugal force is used, the fluid properties of the liquid, such as viscosity and surface tension, are significant. It is well within the ordinary skill in the art to formulate suitable liquid agents by adjusting the composition of the liquid and the dimensions of the chambers and passages within which the liquid is contained. However, the correct balance of properties to ensure that the liquid flows sufficiently easily for the limited operating life to be initiated reliably when the disc is first read, without flowing so easily that the operating life is initiated prematurely by jolts or jerks in transport, may require precise formulation.
There is therefore a continuing need for an improved optical disc or other storage medium that more reliably initiates its limited-life function when, and not until, the disc is first played.
SUMMARY
One embodiment of the present invention provides a limited-life data storage medium that in normal use is subject to rotation when read. The medium comprises a data storage region for storing readable data, and a reservoir containing a flowable agent so arranged that the agent can flow from the reservoir to permanently interfere with the readability of the data. In normal use, forces associated with the rotation of the disc tend to cause flowing of the agent from the reservoir. In a ready-to-play condition with the agent in an initial position in the reservoir, the center of gravity of the disc does not coincide with the normal center of rotation of the disc, and vibration caused by the unbalanced rotation of the disc tends to cause or assist flowing of the flowable agent when the disc is played.
One embodiment of the present invention provides a limited-life disc comprising a flowable agent such as a liquid that is arranged to be redistributed by forces arising when the disc is played, and that when redistributed is arranged to limit the useful life of the disc, for example by corroding a data storage layer over a predetermined time. In a ready-to-play condition the center of gravity of the disc does not coincide with the center of rotation of the disc, but redistribution of the liquid agent when the disc is played reduces the separation between the center of gravity and the center of rotation.
The separation of the center of gravity from the center of rotation in the ready-to-play condition is preferably sufficient to cause a perceptible vibration of the disc when the disc is played in an ordinary CD or DVD player. The separation may result in sufficient vibration that the disc in the ready-to-play condition cannot be read by an ordinary CD or DVD player until redistribution of the flowable agent reduces the vibration. The vibration may have an amplitude of 0.1 mm or more when the disc is rotating at CD audio speed (approximately 16 revolutions per second) in an ordinary CD or DVD player.
The flowable agent may be a liquid, in which case the liquid may be too viscous to be redistributed by centrifugal force from the rotation of the disc without the assistance of the vibration. The flowable agent may be a thixotropic material or a solid of low shear strength that would not flow, or would not flow to a material extent, under the action of centrifugal force from the ordinary rotation of the disc without vibration.
The flow of the flowable agent may be caused substantially entirely by the vibration, or by a combination of vibration and centrifugal force.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.
In the drawings:
FIG. 1 is a schematic drawing of an optical disc.
FIG. 2 is an enlarged view of a central part of the disc shown in FIG. 1 .
DETAILED DESCRIPTION
Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
Referring initially to FIG. 1 , one embodiment of a data storage disc, indicated generally by the reference numeral 10 , is in the form of an optical disc, which except as described below may be generally similar to the disc 10 shown in U.S. Patent Application Publication No. 2005/0195728, and in the interests of conciseness parts of that description summarizing the conventional structure of a CD or DVD are not here repeated in full. The disc 10 is circular, and has an outer periphery 12 .
The optical storage medium 10 is a laminate that consists essentially of, in order, a first rigid substrate 14 , a first layer of reflective material 16 , a layer of adhesive, and a second rigid substrate (not shown) which except as discussed below may be substantially the same as the first rigid substrate 14 . A second layer of reflective material (not shown) which except as discussed below may be substantially the same as the first layer of reflective material 16 , and/or a decorative layer or a layer bearing human-readable indicia, may also be present between the layer of adhesive and the second rigid substrate. The substrates include a central aperture or opening 24 and are made of transparent material, such as plastic, for example, transparent polycarbonate plastic. Polycarbonate is presently preferred, because it is commonly used for commercially-available CDs and DVDs, and the processes for forming polycarbonate into the substrate 14 are widely available and well understood.
In the embodiment, the first reflective layer 16 is a metal coating formed on the first rigid substrate, and the second reflective layer, if present, is a metal coating formed on the second rigid substrate. The two halves thus formed are then joined together with a layer of hot-melt glue or other adhesive. In pressed CDs and DVDs, the metal coating forming the reflective layers is commonly aluminum, but may instead by silver, or other metals. In recordable CDs and DVDs, the metal coating is usually silver.
The optical storage medium 10 includes readable data or information represented by pits, bumps, dots, or other markings formed in the first reflective layer 16 and having a reflectivity different from the reflectivity of other markings or of unmarked parts of the first reflective layer. The markings are scanned by a laser through the first rigid substrate to read the data. In the embodiment, the markings are preferably pits or dots pressed or molded into the surface of the first substrate before the first substrate is coated with the first reflective layer. Various methods for forming the first rigid substrate and the first reflective layer are known and, in the interests of conciseness, will not be further described here.
The second rigid substrate, with the second reflective layer applied to it as a coating, may be similarly formed. The second reflective layer may be a further data storage layer, read either through the first rigid substrate and the first reflective layer, if the first reflective layer is partly reflective and partly transparent, or through the second rigid layer. Alternatively, the second reflective layer may be merely a dummy layer. If the second reflective layer is not used for data storage, it may be omitted. In accordance with the industry standard for DVDs and CDs, the data stored on the first reflective layer starts with a lead-in section 26 at the radially inner edge of the first reflective layer, nearest to the central aperture 24 . This configuration is especially suitable for a DVD-9 format disc, in which the first reflective layer is read from the center outward, and the second reflective layer is then read from the circumference inward.
A first reservoir 30 is formed in the second rigid substrate, or alternatively in the first rigid substrate. The first reservoir is in the form of an annular groove in the inner face of the second rigid substrate, extending round a majority of arc of the disc 10 , for example, for approximately 350° of arc. The shape of the first reservoir is described in more detail below with reference to FIG. 2 . The first reservoir or groove 30 is separated from the central aperture 24 of the disc 10 by a land 40 . Near one end, the groove 30 is connected with the exterior by a hole 32 passing through the thickness of the second rigid substrate. Near the other end, the groove 30 is connected by a radial passageway 34 to a second reservoir or groove 36 . The second reservoir 36 is annular, and is concentric with the disc 10 and is radially outside the first reservoir 30 . A wall 38 separates the first reservoir 30 from the second reservoir 36 , and is penetrated only by the radial passageway 34 .
The second reflective layer has its inner edge at the outer edge of the second reservoir 36 . However, the lead-in section 26 of the first reflective layer overlaps, and forms at least part of one wall of, the second reservoir 36 . The first reflective layer does not overlap the first reservoir or groove 30 . Preferably, the inner edge of the first reflective layer is outside the wall 38 . Because the position of the lead-in section 26 is effectively determined by the industry standard for CDs, DVDs, and similar media, this effectively determines the radial position of the second reservoir 36 . If the second reflective layer is the second data layer of a DVD-9 disc, the DVD-9 standard tolerates having the inner, lead-out edge of the second data layer a few millimeters further out than usual.
The adhesive is applied by coating the second rigid substrate, and the second reflective layer already laminated onto the second rigid substrate, but not applying any adhesive into or over the recesses forming the reservoirs 30 and 36 and the passageway 34 . This ensures that the lead-in section 26 is exposed to the outer reservoir 36 , while the inner reservoir 30 is entirely enclosed by polycarbonate and adhesive.
Referring now also to FIG. 2 , in one example the disc 10 is a standard DVD that is approximately 54 mm in radius to the periphery 12 , with a central hole 24 that is 9.5 mm in radius. The first reservoir 30 has an outer edge 52 with a radius of 20 mm, and an inner edge 54 with a radius that is partly 14 mm and partly 16.5 mm. Starting from the filling hole 32 , the inner edge 54 of the first reservoir 30 has the radius of 16.5 mm for about 35° of arc around the center of the disc 10 , the radius of 14 mm for about 110° of arc around the center of the disc 10 , the radius of 16.5 mm for about 90° of arc around the center of the disc 10 , and the radius of 14 mm for about 110° of arc around the center of the disc 10 . There remains a space of about 15° of arc around the center of the disc 10 between a first end 56 of the inner reservoir 30 , which is a semicircle centered on the filling hole 32 , and the opposite end 58 . this 15° space is occupied by a land 60 that joins the central land 40 to the wall 38 . The outer reservoir 36 is bounded by an outer edge 62 of radius 24.25 mm, and an inner edge 64 of radius 21.5 mm, and extends through approximately 305° of arc from the wall 58 to an opposite end 66 . The two ends 58 and 66 of the outer reservoir 36 are separated by a land 68 that lies outside the part of the inner reservoir 30 with the filling hole 32 and is continuous with the land 60 . The passageway 34 separates the wall 38 from the reservoir end 58 .
As may be seen in FIG. 2 , the resulting configuration is almost symmetrical about a line extending through the center of the disc 10 , approximately through the middle of the land 68 on one side and through the middle of the portion 70 of the first reservoir 30 with inner radius 16.5 mm opposite. In a direction along the mentioned line, the disc 10 is less symmetrical. The widened portion 72 of the land 40 alongside the narrow portion 70 of the first reservoir 30 is larger than the widened portion 72 of the land 40 alongside the filling hole 32 , but not as large as the combined area of the land portions 60 , 68 , and 74 .
However, if the disc 10 is made largely of polycarbonate with a density of 1.2 kg/dm 3 , the outer reservoir 36 is filled with a flowable agent having a density of, for example, 1.03 kg/dm 3 , and the inner reservoir 30 contains only vapor with a density of the order of 0.001 kg/dm 3 , it has been calculated that the disc 10 can be balanced sufficiently precisely that the center of gravity of the whole disc is within 10 or 20 nanometers of the geometrical center of the hole 24 , which will be the center of rotation of the disc 10 in a disc player. The exact dimensions for centering the mass of the disc to a desired precision may be determined by conventional methods using commercially-available computer aided design software, and in the interests of conciseness are not further described here. Perfect balancing of the disc 10 may be considered ideal, but in practice it is usually sufficient for the disc 10 to be balanced within the normal tolerances for conventional discs of the same format.
On the other hand, if the same flowable agent is entirely confined to the widened part 76 of the inner reservoir 30 between the filling hole and the narrow part 70 , an imbalance results laterally of the previously mentioned radial line. It has been calculated that under this condition the center of gravity may be approximately 9 μm from the center of rotation. Even for a music CD playing at 1000 rpm, that is sufficient to cause a perceptible vibration of the disc 10 . The vibration may have an amplitude of 0.1 mm or more, and may be sufficient to prevent reading of the disc by an ordinary CD player. For a computer disc, which may run 8 or 12 times as fast, the vibration may be considerably stronger for a given imbalance of the disc, or the same vibration may be achieved with a smaller imbalance. Where the initial vibration is sufficient to prevent reading of the disc by an ordinary CD player, that has the consequence that if for any reason the flowable agent 42 fails to migrate promptly when playing is started, the disc 10 becomes an unusable disc, rather than a disc with longer than intended (and possibly indefinite) life. That consequence may be desirable in some applications and undesirable in other applications.
By way of contrast, in discs manufactured as described in my co-pending U.S. Patent Application Publication No. 2005/0195728, the center of gravity is typically around 6 μm from the center of rotation, and that distance does not change appreciably when the liquid agent moves from the first to the second reservoir.
Once the disc 10 has been assembled, a liquid or other flowable chemical agent 42 is introduced into the first reservoir 30 through the hole 32 . After the agent 42 is introduced, the hole 32 is then sealed with a drop of adhesive.
In normal storage and handling of the disc 10 , where the agent 42 is a runny liquid, the liquid 42 is retained in the part of the first reservoir 30 nearest the hole 32 by surface tension. Where the agent 42 is a soft solid, the agent 42 is retained by the stiffness of the solid. Where the agent 42 is a viscous liquid or a thixotropic material, both stiffness and surface tension may assist. It is preferred to fill the wider portion 76 of the first reservoir 30 next to the filler hole 32 to a point just beyond the transition to the narrower portion 70 . It is preferred to use a volume of flowable agent 42 substantially equal to the volume of the outer reservoir 36 . This allows a reasonable amount of agent 42 , while leaving a substantial length of dry groove 30 , so that even if the flowable agent 42 is liquid and sudden movements of the disc 10 cause some migration thereof, the liquid 42 is very unlikely to reach the passageway 34 . A greater or smaller amount of the flowable agent 42 may be used, provided that the amount is coordinated with the shape of the reservoirs 30 and 36 to ensure the desired imbalance before migration of the agent 42 and the desired balance after migration of the agent.
However, when the optical storage medium 10 is used, the disc is rotated very rapidly, typically at least 1000 rpm, to allow it to be read by a fixed laser. This rapid rotation of the unbalanced disc 10 generates a considerable vibration. This vibration causes the flowable agent 42 to spread along the groove 30 until the agent reaches the passageway 34 . The agent 42 then spreads along the second reservoir 36 , where it comes into contact with the lead-in section 26 of the data on the first reflective layer 16 . The centrifugal force caused by the rotation of the disc 10 may assist the distribution of the agent, by providing an extra bias to the dispersion, encouraging the agent to move to, and spread along, the outer edge of the first reservoir 30 , to move outwards from the first reservoir 30 to the second reservoir 36 through the passageway 34 , and to spread along the outer edge of the second reservoir 36 , where the agent contacts the lead-in section 26 . Alternatively, or in addition, tangential forces resulting from angular acceleration of the disc 10 as it is read in combination with the inertia of the flowable agent 42 , and/or impulses arising from sudden changes in angular acceleration, may assist the movement of the flowable agent.
It is presently preferred to select the properties of the agent 42 and the amount of vibration such that the agent 42 will migrate from the wider portion 76 of the first reservoir 30 to the second reservoir 30 under the effect of vibration alone. However, an agent that migrates only under the combined effect of vibration and centrifugal or other forces arising from the rotation of the disc 10 , together with any capillary attraction, may also be used.
As the agent 42 advances round the first reservoir 30 , the center of gravity of the disc 10 , and thus the amount of vibration, will vary. Initially, the agent 42 , and the center of gravity, will shift towards the side of the disc with the reservoir portion 70 . As the agent 42 spreads further, the imbalance will gradually reduce. However, the migration of the agent 42 can be assisted by making the part 78 of the first reservoir 30 nearer to the passage 34 , or at least the outer edge of that part, deeper than the parts 70 , 76 in which the liquid was initially confined. The radially inner area of the part 78 of the first reservoir 30 does not contain flowable agent 42 in normal operation, even when the agent is migrating from the reservoir part 76 to the passage 34 , and may be shaped primarily to balance the disc.
The agent 42 in the first reservoir 30 is a preselected chemical agent that will render the lead-in section 26 of the optical storage medium 10 unreadable after a preselected period of time, by dissolving or otherwise reacting with the aluminum or other metal first reflective layer and altering its reflectivity so that the laser cannot read the data. In the preferred embodiment, the agent 42 dissolves away the metal layer over a period of a few minutes to a few days, depending on the intended use. It is not necessary to obliterate the data on the first reflective layer entirely. Merely damaging the lead-in section 26 renders the disc 10 unusable in any standard DVD or CD player, because the player relies on information in the lead-in section to identify and locate the data files stored on the main part of the disc.
Aluminum, which is a material widely used for the reflective layers of CD and DVD discs, has relatively low reactivity in that, due to its characteristics, it is protected by a cover of oxide at any time. Despite this low reactivity, aluminum is known to react to certain chemicals under certain conditions and circumstances when the aluminum oxide is dissolved by a chemical agent that can, because of the dissolution of the oxide, react with the aluminum. For example, aluminum is sensitive to bases such as NaOH or KOH, acids such as HCl, H 2 SO 4 , HNO 3 , and citric acid, and several metallic salts, such as CuSO 4 , NaCl, silver nitrate, and gold chloride, as a few examples.
The properties of these chemical agents may be advantageously used to facilitate and control the rate of dissolution or corrosion of the aluminum. For example, the corrosion of an aluminum reflective layer 16 may be steady and uniform with certain agents, such as NaOH or HCl, or the layer may become pitted upon exposure to agents such as CuSO 4 .
In particular, a solution of NaOH with a concentration of 0.06 g/l and a pH of 11 generates a rate of dissolution of the aluminum reflective layer 16 ranging anywhere between approximately 0.3 micron per hour and approximately 1.0 micron per hour. In a typical DVD, the thickness of the aluminum reflective layers is typically 40 or 50 nanometers. With the above-mentioned NaOH solution, therefore, an operating life of from 2½ to 10 minutes will result. If a longer operating life is desired, inhibitors like soda silicate can reduce or delay the action of NaOH, thereby reducing the rate of dissolution of the aluminum of the reflective layer 16 , and extending the period over which the data will become unreadable. Alternatively, the operating life could be adjusted by changing the thickness of the aluminum layer and/or the concentration of the NaOH solution.
A solution of HCl with a concentration of 5.0% produces a rate of dissolution of the aluminum of the reflective layer 16 ranging anywhere between approximately 1.0 microns per 24 hours and approximately 3.0 microns per 24 hours, giving an operating life of around 20 minutes to 1 hour without special thickening of the aluminum layer. Inhibitors can reduce or delay the effects of the HCl even further, thereby reducing the rate of dissolution, and extending the period over which the data will be readable.
As yet another example, a solution of CuSO 4 with a concentration of 1.0% produces a rate of dissolution of the aluminum of the reflective layer 16 ranging anywhere between approximately 1.0 microns per 24 hours and approximately 2.0 microns per 24 hours.
With the above-mentioned reagent solutions, therefore, a reasonable operating life for a DVD of from several hours to a few days will require either that the lead-in portion 26 of the first reflective layer 16 be specially thickened over the typical 40 or 50 nanometers, or that a weaker solution of the reagent be used.
Alternatively, a mixture of one part saturated citric acid in water, two parts saturated NaCl in water, and twenty parts aqueous carrier medium disables a typical aluminum reflective layer in a DVD in between 8 and 24 hours at room temperature.
Care should be taken that the liquid chemical agent 42 does not dissolve the polycarbonate or other material of the substrates 14 and 22 , and does not dissolve the adhesive 18 . Even if the disc 10 is kept for a long period after it ceases to be usable, the agent 42 is unlikely to dissolve out along the layers of reflective material 16 and 20 and escape at the edge of the disc, because of the narrowness of the gap that would be formed by such dissolution. The agent 42 should, however, not be such a strong corrosive agent that it would create a hazard to persons or property if the liquid were released by breaking the disc 10 .
Another factor is the type of metallic material used for the reflective layer 16 . Although aluminum is presently widely used, other types of metallic material may be used with the optical storage medium 10 . Therefore, the type of metallic material used for the reflective layer 16 should be taken into account to determine the type, concentration, and amount of the chemical agent 42 needed. The same reagents mentioned above may be used in approximately the same concentrations with silver as the reflective layer.
Other examples of suitable agents 42 include: a concentrated aqueous solution of NaCl and CuSO 4 , giving an operating life of approximately 10 minutes in a disc 10 where the reflective layer is aluminum; a solution of 1% NaCl and 1% CuSO 4 in a medium of 80% propylene glycol and 20% water, giving an operating life of approximately 5 minutes in a disc 10 where the reflective layer is aluminum on copper; a solution of 1% NaCl and 1% CuSO 4 in a medium of 80% propylene glycol and 20% water, giving an operating life of approximately 5 minutes in a disc 10 where the reflective layer is silver; and a solution of from 1% to 15% KCl in a medium of 80% propylene glycol and 20% water, giving an operating life of approximately 5 minutes in a disc 10 where the reflective layer is silver. The KCl composition in glycol and water used with a silver disc is presently preferred. The glycol and water mixture is further described in co-pending U.S. Patent Application No. 60/860,567 filed Nov. 21, 2006.
Because the liquid chemical agent 42 is retained in the first reservoir 30 solely by capillary action, the surface tension of the liquid and the readiness with which that liquid wets the material forming the first reservoir and the second reservoir 36 are important. It has been found that with a water-based liquid 42 that does not contain any additives materially altering the surface tension or wetting properties, and polycarbonate substrates 14 and 22 , a first reservoir with portions 76 and 70 from 0.03 mm to 0.4 mm deep in the axial direction is suitable. A depth of 0.25 mm is presently preferred. In the portion 78 , the depth may increase to 0.35 mm. Because of the large difference between the width and the depth, only the depth is important for liquid flow. If the reservoir 30 is too shallow, then the liquid 42 will not reliably disperse under the action of the vibration from the unbalanced disc at the normal operating speed of a CD or DVD, even when assisted by centrifugal force. If the reservoir 30 is too deep, then the agent 42 may flow out too easily before the disc 10 is used, especially if the agent is a low-viscosity liquid. For the second reservoir 36 , a depth of 0.2 mm is presently preferred. In the interests of stability, it is preferred that the second reservoir 36 contain all of the agent 42 , and the agent 42 fill the second reservoir 36 , once the migration of the agent is completed, so the width and depth of the second reservoir are related to each other and to the volume of agent provided.
Other agents may require different dimensions for the reservoirs 30 and 36 . For example, a liquid that wets the substrates more readily than water may require a shallower reservoir. If an ink is added to make the liquid 42 visible, and thus make it easier to see if the liquid has been expelled into the second reservoir, it should be borne in mind that many inks contain a surface active agent that may affect the behavior of the liquid. Testing the capillary behavior of a specific liquid in a specific medium, such as polycarbonate, and adjusting the designed depth of the reservoirs 30 and 36 is routine.
If the depths of the reservoirs are adjusted for a liquid with different surface tension, wetting power (contact angle) on polycarbonate, or other fluid properties, then the balance must of course be recalculated. However, as noted above, the radially inner parts of the reservoir section 78 are not important to the liquid flow, and can be reshaped to adjust the balance in both the X and Y directions marked in FIG. 2 .
The flowable agent 42 may be an agent other than a free-flowing liquid. For example, my copending U.S. Patent Application No. 60/860,567 filed Nov. 21, 2006, proposes a storage medium 10 in which the flowable agent 42 is a mixture of water and glycol. For example, ethylene glycol, with a viscosity at 298 K of 16 mPa·s, or 1, 2 propylene glycol, with a viscosity at 298 K of 40 mPa·s, (compared with 1.000 mPa·s for water) may be used. By selection of a suitable glycol, an agent 42 that has the properties of a soft wax with low shear strength can be produced. Examples include polyethylene glycols such as those in the range of PEG 600 to PEG 1500, which are hygroscopic solids with low melting points (around 17-22° C. for PEG 600 and around 42-48° C. for PEG 1500).
Experiments with an electromagnetic vibrator on a non-rotating sample disc suggest that such a medium can disperse satisfactorily from the first reservoir part 76 to the second reservoir 36 , and can distribute itself so as to reduce the vibration to within the tolerance of an ordinary CD or DVD reader, even with no assistance at all from centrifugal force. In the experiments, either a sample DVD 10 or a turntable simulating the motion of a disc drive with a sample DVD 10 mounted on the turntable was fixed to a commercially available vibratory conveyor, enabling the effects of both vibration alone and vibration combined with rotation to be determined. Both the speed of rotation and the speed and amplitude of the vibration were variable. In addition, a sample DVD 10 mounted on a turntable was used without the vibratory conveyor but with a small weight attached asymmetrically to the DVD 10 in various positions to simulate the effect of various levels of unbalance. By these experiments, it was possible to separate the effects of rotation and the effects of vibration, and to assess the amount of vibration caused by various amounts of unbalance. The test results confirmed that for a practical embodiment of a DVD in accordance with the embodiment shown in FIGS. 1 and 2 the desired movement of the agent 42 can be achieved by vibration resulting from unbalance, even without assistance from the centrifugal force or other rotational effects.
Other media that may be used for the flowable agent 42 include aqueous media rendered thixotropic by a suitable additive, for example, the fumed silica material available under the Registered Trademark CAB-O-SIL from Cabot Corporation of Billerica, Mass.
It is desirable for the agent 42 to spread freely along the second reservoir 36 . Because the second reservoir 36 is bounded partly by the reflective metal or other material of the lead-in section 26 , the behavior of the agent 42 may be different in the first and second reservoirs. The water-based and glycol-based liquids mentioned above are particularly suitable in the present embodiments, because they wet aluminum or silver more readily than they wet polycarbonate, so they flow more freely in the second reservoir 36 than in the first reservoir 30 .
Various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention.
The embodiments of the invention described above with reference to the drawings relate primarily to the distribution of motion pictures and other entertainment media for use by members of the public over a limited period of time, typically from a few hours to a few days. However, the invention has applicability for other situations where a storage medium that remains readable for only a limited period after activation is desired. For example, if the disc 10 is used to distribute computer programs or other information that is to be installed from the disc 10 onto a computer or the like, a life of from a few minutes to a few tens of minutes after the disc is first activated may be sufficient to allow installation on one computer, while frustrating attempts to install on multiple computers.
Although the destruction of the lead-in section of a CD-ROM or DVD disc provides a simple and effective embodiment of the invention, other parts of the information on a storage medium could be destroyed, depending in part on the arrangement of the specific storage medium. For example, any part of the information on the medium could be destroyed, provided the destruction of that information is effective to render the medium unusable to the ordinary user. The information need not actually be destroyed, but could alternatively be obscured or obliterated so that the information cannot be reliably read by generally available playback devices. Alternatively, the medium could be constructed so that only part of the information on the disc becomes unusable.
Although the present specification refers to the disc 10 or other storage medium becoming unusable after a predetermined time, it is not usually necessary for the operating life of the medium to be very precisely predetermined. For consumer protection purposes, it is desirable to be able to specify a minimum operating life, defined so that a disc 10 becoming unusable in less than the minimum operating life would be regarded as defective. For the benefit of the owner of the copyright in the motion picture or other information stored on the disc 10 , who wishes to be sure that the purchaser receives only the benefit that the purchaser has paid for, it is desirable to be able to specify a maximum operating life, defined so that a disc 10 remaining usable for more than the maximum operating life would be regarded as defective. However, in many commercial models the maximum operating life may acceptably be several times the minimum operating life. The disc may then have a typical or nominal operating life that is somewhere between the minimum and the maximum, and any of those measures of the operating life of the disc may be regarded as a “predetermined” life.
Although the described embodiment involves a disc 10 in which the information content is molded onto the substrate layers, a writable disc 10 on which information is “burned” after the disc is assembled is possible. A writable disc either would have a comparatively long operating life that starts when the disc is burned, or would be charged with the liquid chemical agent 42 after burning is completed.
Although specific physical forms for the flowable agent 42 have been described, any agent 42 may be used that has the desired properties. In order to minimize the hindrance to reading of the disc caused by the vibration, it is preferred that the agent 42 migrate rapidly when reading starts, and that the destruction of data or other interference with reading take effect over a longer period of time. The limited life of the disc is then determined primarily by the time taken for the destruction of data or other inhibition of reading to take effect after migration.
The novel features disclosed in the present application may be combined with the features disclosed in my co-pending U.S. Patent Application No. 60/860,615 filed Nov. 22, 2006, and U.S. Patent Application No. 60/860,567 filed Nov. 21, 2006.
Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
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A limited-life storage medium comprises a flowable agent. In one example, the storage medium is an optical disc. In a ready-to-read condition, the center of mass of the disc does not coincide with the center of rotation. When the disc is read, the unbalanced rotation of the disc causes vibration that migrates the flowable agent into contact with a metal data-carrying layer, where the flowable agent interferes with the readability of the data so as to limit the useful life of the disc. The movement of the flowable agent improves the balance of the disc, and reduces the vibration.
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BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a device for applying powder to sheets passing sequentially through a printing press in a conveying direction along a conveyor route, the sheets being combinable into a sheet pile in a manner that one respective side of the upper and rear sides of a respectively following sheet is situated opposite the other respective side of the upper and rear sides of a respectively preceding sheet, after powder has been applied thereto through the intermediary of a powder-bearing gas curtain associated with the conveyor route and formed of a carrier gas conveying powder particles therewith, and further relates to such a powder-applying device in combination with a delivery of a sheet-processing printing press.
Heretofore known devices for applying powder to sheets have a powder-bearing gas dispensing device, such as a sprayer, which produces a powder-bearing gas curtain directed against the upper side of the sheets. This upper side is the front or recto side in the case of sheets which are printed on only one side thereof. The powder-bearing gas is made-ready in or supplied to the powder-bearing gas dispensing or sprayer device by a powder-bearing gas generator which distributes powder particles in a carrier-gas flow. By applying powder to the sheets, the latter are prevented from being baked together if a coating thereon of printing ink or varnish has not yet hardened completely when the sheets have been laid upon one another on a sheet pile.
In the heretofore known conventional devices, the powder-bearing gas dispensing or spraying device must be arranged at a relatively great distance from the conveyor route of the sheets in order that the grippers moving the sheets can run through unhindered between the sheets and the powder-bearing gas dispensing device. For this reason, the transfer of powder onto the sheets is not always satisfactory.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a device for applying powder to sheets which transfers the powder onto the sheets more effectively than heretofore known devices of this general type.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a device for applying powder to sheets passing sequentially through a printing press in a conveying direction along a conveyor route, the sheets being combinable into a sheet pile in a manner that one respective side of upper and rear sides of a respectively following sheet is situated opposite the other respective side of the upper and rear sides of a respectively preceding sheet, comprising a device for generating a powder-bearing gas curtain associated with the conveyor route and formed of a carrier gas conveying powder particles, and for applying the powder of the gas curtain to the rear side of the respective sheets prior to the combination of the sheets into the sheet pile.
In accordance with another feature of the invention, the powder-applying device comprises a sheet-guiding device for expelling the powder-bearing gas so as to form the powder-bearing gas curtain, the sheet-guiding device being formed with a sheet-guiding surface following the conveyor route.
In accordance with a further feature of the invention, the sheet-guiding device includes a nozzle strip for expelling the powder-bearing gas.
In accordance with an added feature of the invention, the sheet-guiding surface is formed with a cutout assigned to the nozzle strip for passage therethrough of powder-bearing gas expelled from the nozzle strip.
In accordance with an additional feature of the invention, the powder-applying device includes grid rods received in the cutout, the grid rods being disposed at an inclination to the conveying direction of the sheets. This construction provides the advantages that the sheet-guiding device has a sheet-guiding function even in a region where it ejects the powder-bearing gas, and that the sheets are coated uniformly with powder particles, and that, consequently, no powder-free strips are produced.
In accordance with yet another feature of the invention, the sheet-guiding surface is provided with sliding-air dispensing nozzles for expelling sliding air so as to form an air cushion between the sheet-guiding surface and a respective sheet, and powder-bearing gas dispensing nozzles for expelling the powder-bearing gas. This development permits a particularly efficient production of a sheet-guiding plate forming the sheet-guiding surface of the sheet-guiding device.
In accordance with yet a further feature of the invention, the powder-bearing gas dispensing nozzles are disposed in a region of the sheet-guiding device located upstream with respect to the conveying direction of the sheets. This ensures a particularly effective transfer of powder because, downstream from the powder-bearing gas dispensing nozzles, no further air flows or currents, which would blow powder away again, are directed against the rear sides of the sheets.
In accordance with yet an added feature of the invention, the powder-bearing gas dispensing nozzles, respectively, emit a powder-bearing gas jet cluster oriented substantially in the conveying direction of the sheets.
In accordance with yet an additional feature of the invention, the powder-bearing gas dispensing nozzles are formed in at least one row arranged transversely to the conveying direction of the sheets, and the powder-bearing gas jet clusters, towards the ends of at least one row thereof, are oriented increasingly laterally away from the conveying direction to the outside. This construction is advantageous with regard to effective powdering of the lateral edge regions of the sheets, without requiring that the powder-bearing gas dispensing nozzles be provided up to the edges of the sheet-guiding device.
In accordance with still another feature of the invention, the sliding-air dispensing nozzles and the powder-bearing dispensing nozzles have a similar geometric construction.
In accordance with still a further feature of the invention, the powder-applying device includes a powder-bearing gas nozzle chamber, the powder-bearing gas dispensing nozzles, respectively, being formed by an inclined, sector-shaped base wall widening outwardly from the interior of the powder-bearing gas nozzle chamber, the base wall rising to the sheet-guiding surface. With such a construction, a jet of powder-bearing gas emerging from a respective powder-bearing gas dispensing nozzle fans out as it increasingly approaches the sheet. This is advantageous with regard to effective utilization of the powder entrained by the carrier gas.
In accordance with still an added feature of the invention, the powder-applying device includes a powder-bearing gas tube for supplying powder-bearing gas during operation to the powder-bearing gas dispensing nozzles, the tubes, respectively, having an opening communicating with the powder-bearing gas nozzle chamber, and a baffle element is disposed opposite the respective tube opening. This development is also advantageous with regard to a homogeneous application of powder.
In accordance with still an additional feature of the invention, the sheet-guiding device is formed with rows of alternatingly succeeding powder-bearing gas dispensing openings and suction openings extending transversely to the conveyor direction. Thus, local powder-bearing gas flows or currents are generated which have a component of movement transverse to the conveying direction of the sheets. The gas flows or currents containing residual powder are sucked up again quite early, with the result that only a little unused powder is dispensed into the environment.
In accordance with another feature of the invention, the suction openings are offset upstream with respect to the conveyor direction from the powder-bearing gas dispensing openings. This construction ensures that residual powder is sucked off particularly effectively.
In accordance with a further feature of the invention, the powder-applying device includes respective comblike distributor units with which the powder-bearing gas dispensing openings, on the one hand, and the suction openings, on the other hand, communicate.
In accordance with an added feature of the invention, the sheet-guiding surface is formed with a multiplicity of openings, and the powder-applying device includes a distributor box communicating with the openings, a feed shaft terminating in the distributor box and having therein a sliding-air flow emerging from the openings, and at least one nozzle for dispensing the powder-bearing gas in the form of a powder-bearing gas cone, the at least one nozzle terminating in the feed shaft. With this relatively simple construction, the powder-bearing gas can be added to the sliding air.
In accordance with an additional feature of the invention, the powder-applying device includes at least one fan disposed within the feed shaft for generating the sliding-air flow.
In accordance with yet another feature of the invention, the powder-bearing gas cone and the sliding-air flow intersect.
In accordance with yet a further feature of the invention, the powder-bearing gas cone has an aperture angle ranging between 40° and 80°.
Thus, an intensive mixing of powdering gas and sliding air without any relatively large apparatus is possible.
In accordance with yet an added feature of the invention, the powder-applying device includes a powder-bearing gas trap disposed upstream with respect to the conveyor direction from the powder-bearing gas curtain. This is advantageous with regard to avoiding the escape of residual powder into the environment of the device.
In accordance with yet an additional feature of the invention, the powder-bearing gas trap is formed as a doctor blade arrangement. With this construction, gas containing residual powder is positively disposed of.
In accordance with still another feature of the invention, the powder-bearing gas trap is formed with disposal openings subjected to negative pressure during operation, and with supply openings arranged upstream therefrom with respect to the conveyor direction of the sheets, the supply openings being closely adjacent to the disposal openings and being subjected to excess pressure during operation. With this construction, effective adhesion of powder particles to the sheets is produced even if the rear sides of the sheets are very dry. Assurance is provided that the gas which is disposed of and which contains residual powder can be replaced by a corresponding quantity of powder-free air.
In accordance with still a further feature of the invention, sliding air is mixed with the powder-bearing gas for generating an air cushion between the sheet-guiding surface and a respective sheet. This permits the same air-cushion effect to be achieved with the powder-bearing gas as is achieved with the sliding-air dispensing nozzles of the sheet-guiding device.
In accordance with still an added feature of the invention, the powder-applying device includes an electrode for electrically charging the powder particles.
In accordance with a concomitant feature of the invention, the powder-applying device is combined with a delivery of a sheet-processing printing press.
By virtue of the fact that powder is applied to the rear side of the sheets, the powder-bearing gas can be dispensed closer to the conveyor route or track of the sheets, because the grippers moving the sheets extend only slightly under the rear side of the sheets. The device according to the invention also maintains the separating function of the powder particles in the sheet pile, because all that is important for the separating function is that the powder particles be present on the separating surface between sheets lying upon one another. Whether they are inserted into this separating surface on the top side of a sheet lying therebelow or from the underside of a sheet lying thereabove is only of secondary interest.
If desired, the device according to the invention can also be used together with a conventional powdering device applying powder to the top side of the sheets.
If a powder-bearing gas dispensing nozzle has a transversely inclined base wall or floor, it is easily possible thereby to produce a jet of powder-bearing gas which is oblique to the conveying direction.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a device for applying powder to sheets, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:
BACKGROUND OF THE INVENTION
FIG. 1 is a fragmentary diagrammatic side elevational view of a multi-color printing press showing an end section thereof;
FIG. 2 is a schematic and fragmentary diagrammatic plan view of the press end section of FIG. 1 showing a sheet-guiding device thereof;
FIG. 3 is a much-enlarged longitudinal sectional view, extending in the sheet-conveying direction, of a powder-bearing gas dispensing nozzle of the sheet-guiding device shown in FIG. 2, together with a gripper unit and part of a sheet conveyed thereby;
FIG. 4 is a sectional view like that of FIG. 3 showing a sheet-guiding device provided with a different embodiment of the powder-bearing gas dispensing nozzle;
FIG. 5 is a fragmentary top plan view of FIG. 4, rotated clockwise through an angle of 90°;
FIG. 6 is a reduced fragmentary schematic and diagrammatic top plan view of FIG. 4 showing a different embodiment of the sheet-guiding device;
FIG. 7 is a view similar to that of FIG. 4 showing schematically and diagrammatically the sheet-guiding device with yet a different powder-bearing gas dispensing nozzle;
FIG. 8 is a fragmentary bottom plan view of a powder-bearing gas trap forming part of the invention; and
FIG. 9 is a sectional view of FIG. 8 taken along the line IX--IX in the direction of the arrows.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and, first, particularly to FIG. 1 thereof, there is shown therein side walls 10 of an end section of a multi-color printing press. Mounted on the side walls 10 are pairs of sprocket wheels 12, 14 which are spaced apart perpendicularly to the plane of the drawing and, respectively, guide a revolving conveyor chain 16. Fitted to the latter at regular spaced distances are very diagrammatically represented gripper units 18 having gripper bars 19 (note FIG. 3) carrying grippers 20 and extending perpendicularly to the plane of FIG. 1 of the drawing, the gripper bars 19 being carried by the conveyor chains 16. As the conveying chains 16 revolve in the direction represented by the arrow 11, the grippers 20 take over the sheets 22 from a last sheet-guiding cylinder 13 of the printing press and convey the sheets 22 along a conveyor route extending essentially up to the sprocket wheels 14 to a sheet stacking station 15, in order to transfer the sheets 22 thereat to a sheet brake 17 which, finally, releases the sheets 22 it has braked to form a sheet pile 21. In this regard, the course of the conveyor route is determined by the course of the lower strands of the conveyor chains 16.
The illustrated section of the conveyor route extending approximately from the cylinder 13 to the sheet brake 17 has a sheet-guiding device 24 assigned thereto and following the course thereof, the sheet-guiding device 24 being formed with a sheet-guiding surface 25. A nozzle strip 26 is integrated into the sheet-guiding device 24 and is formed with a plurality of powder-bearing gas dispensing nozzles, which are not shown in detail in FIG. 1, the nozzles being aligned perpendicularly to the plane of the drawing of FIG. 1 and together producing a powder-bearing gas curtain 28 directed towards the rear side or underside of the sheets 22, thereby providing overall a sheet-guiding device 24 which expels the powder-bearing gas to form the powder-bearing gas curtain 28.
Powder particles with carrier gas guiding the particles are fed to the nozzle strip 26 by a diagrammatically represented powder-bearing gas generator 30 which mixes powder particles, for example, corn particles of small diameter, in a respectively required concentration, with a carrier-gas flow.
In order to apply powder to the rear sides of the sheets in the device shown in FIG. 1, the nozzle strip 26 can be arranged in closer proximity to the conveyor route of the sheets, which runs on or at a slight spacing from the sheet-guiding surface 25 of the sheet-guiding device 24. In contrast, if powder is applied by a nozzle strip to the top or front side of the sheets, the spacing between the top side and the nozzle strip is clearly greater, because the gripper units 18 must move through freely below the nozzle strip.
Because of the relatively small spacing achievable by the device between the nozzle strip 26 and the conveyor route, a very effective transfer of powder onto the rear side of the sheets 22 is achieved. The powder layer applied to the latter then effectively prevents the sheets 22 from baking together in the pile 21 if ink layers, and possibly varnish coatings, applied to the sheets are not yet completely dry.
Because the nozzle strip 26 is integrated into the sheet-guiding device 24, a constant and precise positioning of the rear side of the sheets 22 with respect to the nozzle strip 26, under the dynamic conveying conditions, is produced, which has an advantageous effect upon the uniformity of the powder application.
The sheet-guiding device 24 shown in FIG. 1 cooperates chiefly mechanically with the rear side of the sheets 22, there being a certain air film being formed, however, between the sheets 22 and the sheet-guiding surface 25 because of the speed at which the sheets are conveyed.
In order to achieve reinforced supporting of the sheets 22 in the region of the sheet-guiding device 24 by an air cushion, which is particularly advantageous for sheets which are printed on both sides thereof, the sheet-guiding device 24 is preferably constructed as an air-cushion guiding element, as shown in FIG. 2. Sliding air is blown in between the sheets 22 and the sheet-guiding surface 25 in order to form an air cushion. For this purpose, there are provided a number of sliding-air dispensing nozzles 32 which are arranged in rows and distributed over the sheet-guiding surface 25. The sliding-air dispensing nozzles 32 are respectively connected to a transverse distributor channel 34 having two ends which are connected to a sliding-air feedline 38 via a symmetrical flow divider 36. The sliding-air feedline 38 is connected, in turn, to the outlet of a fan 42 via an adjustable throttle or choke 40. As is apparent from the drawing, the sliding-air dispensing nozzles 32 of rows thereof succeeding one another in the conveying direction are laterally offset with respect to one another by half a division, so that, on average, the sheets 22 are supported uniformly in a transverse direction.
In the plan view according to FIG. 2, the sliding-air dispensing nozzles 32 are shown in the shape of sectors of a circle and, respectively, exhibit an inclined base wall or floor 44 which, while widening from the interior of a sliding-air dispensing chamber 35, rises towards the sheet-guiding surface 25 (note FIG. 4). Accordingly, the sliding-air dispensing nozzles 32 have lateral triangular boundary walls 46.
Provided at the downstream end of the sheet-guiding device 24 shown at the top of FIG. 2 is a row of powder-bearing gas dispensing nozzles 48 extending transversely to the conveying direction of the sheets 22, for clusters of dispensing powder-bearing gas jets 49 which are oriented essentially in the conveying direction of the sheets 22 and, at a respective end of the row of powder-bearing gas dispensing nozzles 48, are inclined laterally outwardly with respect to the conveying direction.
With a respective inclined, sector-shaped base wall 50 and lateral boundary walls 52, the powder-bearing gas dispensing nozzles 48 have a geometry similar to that of the sliding-air dispensing nozzles 32, with the result that a very uniform application of powder can be achieved through the intermediary of widely discharging clusters of powder-bearing gas jets 49. The powder-bearing gas dispensing nozzles 48 are connected to a transverse distributor channel 54 having ends which are connected to the output of a mixing device 58 via a symmetrical flow divider 56. One inlet of the mixing device 58 is connected to an outlet of the powder-bearing gas generator 30, while the other input of the mixing device 58 is connected via an adjustable throttle 60 to an outlet of the fan 42 shown at the bottom of FIG. 2.
In this manner, the powder-bearing gas dispensing nozzles 48 dispense a quantity of powder which is set or adjusted at the powder-bearing gas generator 30 and, simultaneously, a total quantity of air which can be prescribed by adjusting the throttle 60. What is overall accomplished thereby is that, just like the sliding-air dispensing nozzles 32, the powder-bearing gas dispensing nozzles 48 contribute to the formation of the air cushion, powder particles being also applied, however, simultaneously to the rear side of the sheets 22 by the powder-bearing gas dispensing nozzles 48.
As is apparent from FIG. 3, the base wall or floor 50 of the powder-bearing gas dispensing nozzles 48 has a section canted downwardly and constituting a baffle element 62. The canted section 62 is situated opposite an opening 65 formed in a powder-bearing gas tube 64 which leads from the distributor channel 54 into the interior of a powder-bearing gas nozzle chamber 66 surrounding the powder-bearing gas dispensing nozzle 48 and arranged on the underside of a sheet guide plate 27 (in practice, a stainless steel plate) forming the sheet-guiding surface 25. In this manner, the powder-bearing gas is thoroughly mixed once again before emerging from the powder-bearing gas dispensing nozzle 48, and the powder-bearing gas jet emerging from the opening 65 of the powder-bearing gas tube 64 is fanned out. Only after the powder-bearing gas traverses a U-shaped deflecting path which passes below the end of the baffle element 62 and is then guided in a direction counter to the wall of the powder-bearing gas nozzle chamber 66 located at the right-hand side of FIG. 3, does the powder-bearing gas then emerge from the powder-bearing gas dispensing nozzle 48 along the rising base wall or floor 50. By transversely tilting the base wall or floor 50 additionally with respect to the conveying direction, a powder-bearing gas jet cluster 49 emerging from the powder-bearing gas dispensing nozzle 48 can present an orientation which is inclined to the conveying direction. Also apparent from FIG. 3 is the mutual assignment of the sheet-guiding device 24 provided with the powder-bearing gas dispensing nozzles 48, and a sheet 22 guided away thereover by the gripper unit 18.
In a modified construction of the aforedescribed exemplary embodiment, the powder-bearing gas dispensing nozzles 48 are preferably additionally supplied with sliding air. As indicated by broken lines in FIG. 3, a sliding-air dispensing tube 82 opening into the powder-bearing gas nozzle chamber 66 can be provided for this purpose.
In another modified exemplary embodiment, powder-bearing gas can also be applied to the rear side of the sheets 22 by a transversely arranged nozzle strip 84 which, as shown in FIG. 4, is surrounded by a shaft or compartment 86 which is formed with an outlet opening 88 directed towards the rear side of the sheets 22 and extending over the width of the printed sheet 22. The outlet opening 88 is covered by a grating or grid 90, which is recessed into a corresponding cutout 89 incised into the sheet guide plate 27, and is formed of a plurality or multiplicity of grating or grid bars 92 inclined to the conveying direction of the printed sheets 22, as is apparent from FIG. 5. The ends of the grating or grid bars 92 overlap precisely in the direction perpendicular to the conveying direction of the sheets 22 and, in this manner, represent a mechanical continuation of the sheet-guiding surface 25 in the region of the outlet opening 88, while at the same time, however, permitting powder to be applied homogeneously to the rear side of the sheets 22.
In the exemplary embodiment shown in FIG. 4, the row of sliding-air dispensing nozzles 32 directly adjacent the nozzle strip 84 upstream is aligned in an opposite manner, as represented in FIG. 2. Therewith, a sliding-air flow is produced which is locally opposite to the conveying direction of the sheets 22. In this manner, an intensified air-cushion effect is provided locally by stagnation of the sliding air dispensed from the sliding-air dispensing nozzles 32, which are located farther upstream and aligned in the conveying direction, so that the sliding-air current is kept away at least partly from the outlet opening 88 through which powder-bearing gas flows, and the powder-bearing gas effectively reaches the rear side of the sheets 22.
In the exemplary embodiment shown in FIG. 6, a sliding-air box 94 is arranged on the underside of a sheet guide plate 27 forming the sheet-guiding surface 25, and regularly or orderly distributed sliding-air openings 96 are formed in the sheet guide plate 27 within the edge or border contour of the sliding-air box 94.
Provided in an upstream section of the sheet-sliding device 24 are powder-bearing gas dispensing openings 98 and suction openings 100 which alternatingly succeed one another in the transverse direction. The powder-bearing gas dispensing openings 98, on the one hand, and the suction openings 100, on the other hand, are respectively connected to comb-like distributor units 106 and 108, respectively, having respective transversely arranged comb backs, the powder-bearing gas dispensing openings 98 and the suction openings 100, respectively, being arranged on comb teeth 102 and 104, respectively, of which the teeth of one of the comb-like distributor units 106, 108 engage in the gaps between the teeth of the other of the comb-like distributor units 108, 106. The lateral ends of the comb backs, respectively, are connected via symmetrical flow dividers 110 and 112 to the powder-bearing gas generator 30 and the suction side of a fan 114, respectively.
As is apparent from FIG. 6, the suction openings 100 and the powder-bearing gas dispensing openings 98 are arranged in a plurality of rows (three rows in FIG. 6) succeeding one another in the conveying direction and being perpendicular thereto. The suction openings 100, however, are offset overall by one division downstream with respect to the powder-bearing gas dispensing openings 98, so that the local flows from the powder-bearing gas dispensing openings 98 to the suction openings 100 have a component aligned parallel to the conveying direction of the sheets 22 in addition to a predominantly transverse component.
In the exemplary embodiment shown in FIG. 6, residual powder which has not been deposited on the sheets 22 is already largely taken care of again in the region of the sheet-guiding device 24 and not carried into the neighboring regions of the printing press. The residual powder is separated in a cyclone 116 connected to the suction side of the fan 114. In this regard, the intensity of the suction flow through the suction openings 100 is adjusted by an adjustable throttle 118 connected upstream of the inlet to the cyclone 116. In order to ensure satisfactory operation of the cyclone 116 independently of the intensity of this suction flow, a basic air flow or current is maintained through the cyclone 116 by a connection, including a further adjustable throttle 120, provided between the outlet side of the fan 114 and the cyclone 116.
In the exemplary embodiment according to FIG. 7, the sheet-guiding device 24 has a multiplicity of openings 122 which simultaneously serve to produce an air cushion and apply powder to the rear side of the sheets 22. The openings 122 communicate with a distributor box 124 which is connected to a feed shaft 126. In the feed shaft 126, perpendicularly to the plane of the drawing, a plurality of fans 128 are arranged one after another for supplying a sliding-air flow, which emerges from the openings 122, so as to produce an air cushion between the sheet-guiding surface 25 and a respective one of the sheets 22. Downstream opposite a respective fan 128, there is assigned thereto a respective nozzle 130 which dispenses into the supply shaft 126 a powder-bearing gas cone 132 intersecting the sliding-air flow. The powder-bearing gas cone 132 has an aperture angle which, in practice, is between 40° and 80°, and preferably approximately 60°. The nozzles 130 are connected to the outlet of the powder-bearing gas generator 30.
In order to promote the transfer of the powder-bearing gas onto the rear sides of the printed sheets 22, there is fitted on the feed shaft 126 at the end thereof facing the distributor box 124, via conventional insulating elements, which are not shown in detail in the drawing, a net-shaped electrode 136 which is connected to a high-voltage source 138 and charges the powder particles electrically so that the latter adhere effectively to the rear side of the sheets 22 upon impinging thereon.
FIGS. 8 and 9 show a powder-bearing gas trap 140 in the form of a doctor blade arrangement by which powder-bearing gas containing residual powder can be sucked off in a region of the sheet-guiding device 24 located downstream with respect to the powder-bearing gas curtain 28.
The doctor blade arrangement has two blade arms 142 and 144 which together form a V which opens in the conveying direction of the sheets 22 represented by the vertical arrow in the middle of FIG. 8. In sections located upstream on the doctor blade arms 142 and 144, the latter, respectively, have thin guide plates 148 respectively extending upwards obliquely to a baseplate 146. The guide plates 148 are inserted into a V-shaped cutout formed in the baseplate 146 and are connected at upper ends thereof by a thin baseplate 150 which is flush with the sheet-guiding surface 25. Situated below the guide plates 148, respectively, are disposal openings 152 which are connected via manifolds 154 to the suction side of a fan (not shown in FIG. 8).
In a downstream section of the doctor arms 142 and 144, supply openings 156 for powder-free air are formed. The openings 156 are connected via feed lines 158 to a fan (not shown in FIG. 8) which supplies fresh air, although in practice it can be formed by the fan 42 of FIG. 2.
The supply openings 156 are formed so that fresh-air jets emerging therefrom enclose with the plane of the baseplate 146 an angle of, for example, 60°, with the result that, on the one hand, an overall essentially constant support of the sheets by air cushion is attained in the region of the doctor arms 142 and 144, however, on the other hand, the supplied fresh air is already dispensed with a velocity component extending parallel to the conveying direction of the sheet.
Due to the fact that the exchange of air, because of the V-shaped geometry of the doctor blade arrangement, does not take place abruptly, but rather, over a region along the conveyor route of the sheets, abrupt mechanical loadings on the sheets 22 are avoided.
It is noted that the doctor blade arrangement shown in FIGS. 8 and 9, on the one hand, does not act directly mechanically on the sheets, because of air-cushion effects, while, on the other hand, it replaces gas containing residual powder with fresh air. Due to the manner of construction of the supply openings 156, however, the fresh air does not act strongly upon the rear side of the sheets 22, as a result of which, powder particles adhering thereto could be detached again.
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A device for applying powder to sheets passing sequentially through a printing press in a conveying direction along a conveyor route, the sheets being combinable into a sheet pile in a manner that one respective side of upper and rear sides of a respectively following sheet is situated opposite the other respective side of the upper and rear sides of a respectively preceding sheet, includes a device for generating a powder-bearing gas curtain associated with the conveyor route and formed of a carrier gas conveying powder particles, and for applying the powder of said gas curtain to the rear side of the respective sheets prior to the combination of the sheets into the sheet pile.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for the preparation of maltooligosaccharide glycoside derivatives of p-nitrophenol, 4-methylumbelliferone and other chromogenic or fluorogenic aglycones. More particularly, the invention relates to an enzymatic method for the preparation of suitable chromogenic or fluorogenic maltooligosaccharide glycoside derivatives for use, for example, as substrates for the determination of amylase activity.
2. Description of the Prior Art
Heretofore, only processes involving organic synthetic reactions have been used for the preparation for the chromogenic or fluorogenic derivatives of oligosaccharides suitable for use as substrates for the determination of amylase activity. (Jansen and Rawlins, Nature 182, 525, 1958; and Driscoll, Richard C., et al., U.S. Pat. No. 4,102,747. In these methods, the yield of desired derivative, its suitability as an amylase substrate, or its low purity have prevented significant improvements in several analytical systems for the determination of amylase activity which would be possible if such substrates were available in a commercially and technically acceptable fashion.
Amylase assay procedures have been developed which utilize substrates such as starch, glycogen, dextrin, and oligosaccharides. However, the use of such substrates has suffered from the disadvantage that endogenous glucose present in the reaction sample sometimes causes interference with the results of the assay. Procedures utilizing these substrates have been developed which overcome the glucose interference problem, however the reaction sequences involved in these procedures are complicated and often quite costly.
The Driscoll, et al. procedure cited above overcomes the problems of glucose interference and high cost, however, heretofore no satisfactory procedure has been reported for producing the maltooligosaccharide glycoside substrate in a commercially feasible manner. The availability of defined chromogenic or fluorogenic derivatives of maltooligosaccharide glycosides will permit significant improvements in the Driscoll et al. method for the determination of amylase activity according to the following reactions in which the substrate, p-nitrophenyl-α-D-maltoheptaoside is used for illustrative purposes only: ##STR1##
The rate of formation of p-nitrophenol, once zero-order kinetics is established for equation (2) is directly proportional to the amylase present in the sample. p-Nitrophenol may be monitored spectropholometrically by its absorbance at 405 nm.
In a similar fashion, amylase activity may be determined using a fluorogenic substrate such as 4-methylumbelliferyl-α-D-maltoheptaoside. In such a case, the rate of increase in fluorescence is proportional to the amylase activity.
The organic synthetic reactions heretofore used for producing chromogenic and fluorogenic substrates have produced substrates having both α and β configurations. Accordingly, because in the Driscoll et al. method the use of substrates having the β configuration requires the use of β glucosidase as an additional reactant, there is a need for a method for producing substrates having either the α configuration or the β configuration in substantially pure form. The availability of substrates with the β-anomeric configuration would provide improvements in the Driscoll et al. method for the measurement of amylase activity according to the following reactions in which the substrate, p-nitrophenol-β-D-maltoheptaoside is used for illustrative purposes only: ##STR2## The rate of formation of p-nitrophenol, once zero-order kinetics has been established, for reaction (3) is directly proportional to the amylase activity of the sample. p-Nitrophenol may be monitored by its absorbance at 405 nm spectrophotometrically. In a similar fashion, amylase activity can be determined using a fluorogenic substrate such as 4-methylumbelliferyl-β-D-maltoheptaoside. In such a case, the rate of increase in the fluorescence is proportional to the amylase activity.
From the foregong discussion, it can be readily seen that the analytical methods employing chromogenic or fluorogenic substrates for the measurements of amylase activity represent decided improvements in existing technology for the measurment of the enzyme. To render these procedures useful for routine use, there is a need for methods for producing the α and β-maltooligosaccharide glycoside derivatives in substantially pure form and high yield.
The well known glucanotransferase (E.C.2.4.1.19) of Bacillus macerans has primarily been used for the production of cyclic dextrins from starch. (Tilden and Hudson; J. Bact., 43, 727-744, 1942, J. Am. Chem. Soc., 61, 2900-2902, 1939). The use of the enzyme for the transfer of glucosyl groups from cyclic dextrins to suitable acceptors such as D-glucose, D-maltooligosaccharides, and D-glucosides, has been reported (French, et al; J. Am. Chem. Soc. 76 2387-2390, 1954). Also, in British Pat. No. 1,442,480, is reported a method for producing oligoglucoylfructose utilizing a glucanotransferase enzyme isolated from a strain of Bacillus stearothermophilus. A similar enzyme has been isolated from Klebsiella pneumoniae (Bender, Arch. Microbiol., 111, 271-282, 1977) and from Bacillus megaterium (Kitahata, et al., Proc. Symposium on Amylase, Volume 7, 61-68, 1972). Heretofore, the use of glucanotransferase enzymes for the enzymatic synthesis of substantially pure α and β p-nitrophenyl or 4-methylumbelliferyl maltooligosaccharide glycoside derivatives has not been reported.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method for producing an α or β maltooligosaccharide glycoside derivatives in substantially pure form. Another object of the invention is to provide a method for producing α or β maltooligosaccharide glycoside derivatives of p-nitrophenol or 4-methylumbelliferone.
Accordingly, disclosed herein is a method for producing an α or β maltooligosaccharide glycoside derivative in substantially pure form, comprising incubating an aqueous solution of a glucosyl donor and a glucosyl acceptor in the presence of glucano-transferase enzyme (E.C.2.4.1.19) under transglycosylating conditions to form a reaction mixture containing the maltooligosaccharide glycoside derivative; and separating the maltooligosaccharide glycoside derivative from the reaction mixture.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is based upon the transferase activity of the enzyme, glucanotransferase (E.C.2.4.1.19). This enzyme can be isolated from a variety of sources, and enzymes derived from the organisms Bacillus macerans, Bacillus stearothermophilus, Bacillus megaterium, and Klebsiella pneumoniae have been used. The process of the invention is represented by the following formula: ##STR3## The glycosyl donor is generally a cyclic, linear, or branched maltooligosaccharide and preferably includes α-cyclic dextrin, linear maltooligosacharides (for instance, as described by Hall, L. M., U.S. Pat. No. 4,081,326), soluble starch, dextrins, and glycogen. α-cyclic dextrin is the preferred glucosyl donor, in that its use results in high yields of the desired derivatives. According to the general reaction given, the initial reaction product would be dependent upon the specific glucosyl donor used, but because of homologolizing reactions, the initial reaction product is rapidly transformed into larger and smaller chain maltooligosaccharides. These homologolizing reactions are counter-productive to the production of a specific α or β oligosaccharide glycoside in high yield. In accordance with the present invention, it has been found that by controlling reactant and enzyme concentrations, and reaction times within specific limitations, the reaction unexpectedly produces the desired maltooligosaccharide glycoside derivative in high yield. Although formation of desired derivatives occur at concentrations of the glucosyl donor of from about 0.01 to about 1 gram per ml of incubation mixture, it is preferable that the concentration be between about 0.10 and about 0.5 grams per ml, depending upon the derivative being prepared and the glucosyl donor being used. For instance, when the glucosyl donor is α-cyclic dextrin, the preferred concentration is from about 0.10 to about 0.25 grams per ml. The higher concentrations are especially preferred for the preparation of the maltoheptaoside glycoside derivatives, as the yield is greatly dependent upon the concentration of the α-cyclic dextrin.
Generally, any chromogenic or fluorogenic compound which can be reacted with glucose to form a glycoside which is subject to enzymatic cleavage can be used to prepare the glucosyl acceptors of the present invention. Representative of such glycosides are the nitrophenyl, 4-methylumbelliferyl, phenolphthalyl and other such derivatives of glucose. The anomeric configuration of the glucosyl acceptor will determine the anomeric configuration of the resulting maltooligosaccharide glycoside derivative, and the preferred glucosyl acceptors are p-nitrophenyl-α-D-glycoside, p-nitrophenyl-β-D-glycoside, 4-methylumbelliferyl-α-D-glycoside, and 4-methylumbelliferyl-β-D-glycoside. Other glucosyl acceptors include the α or β glycosides of maltose, maltotriose, and maltotetraose. Again, the concentration of the glucosyl acceptor influences the yield of the desired maltooligosaccharide derivative. Although formation of the desired maltooligosaccharide glycoside derivatives occurs at concentrations of glucosyl acceptor which are less than the solubility limit in the incubation mixture, it is preferable to employ the glucosyl acceptors in saturated solution. Thus, in the incubation mixture, it is preferable to use the glucosyl acceptors at concentrations of from about 0.5 to about 100 milligrams per ml, depending upon the glucosyl acceptor being used and the concentration of the glucosyl donor. When p-nitrophenylglucoside acceptors are used, the concentration generally ranges from 13 to about 26 milligrams per ml, depending upon the glucosyl donor concentration, and when 4-methylumbelliferyl derivatives are employed, the concentration generally ranges from about 1.5 to about 1.8 milligrams per ml.
The glucanotransferase enzyme is employed in an amount sufficient to catalyze the transfer reaction in a convenient period of time, typically from about 3 minutes to about 5 hours, preferably from about 25 minutes to about 150 minutes of incubation at 40° C. In general, for the procedures described, it is preferable to have present an amount equal to from about 0.3 units up to about 3.0 units of activity (as hereinafter described) per ml of reaction mixture, depending upon the particular derivative which is being prepared. The glucanotransferase enzyme is prepared and purified in such a manner as to be substantially free of hydrolytic activity and is advantageously stable to prolonged storage in solution at 4° C., and is stable for at least 45 minutes at temperatures up to 60° C. at a pH of from 4.9 to 6.0.
The reactants are incubated under transglycosylating conditions for a time sufficient to effect substantial production of the desired product. Included in such conditions are pH, temperature, and reaction time. The pH of the reaction mixture is maintained from about 4.9 up to about 6.0, preferably from about 5.2 to 5.4. Any suitable buffer may be employed in the incubation mixture which adequately controls the pH in the specified region. Sodium or potassium acetate buffers are preferable. The concentration of buffer is generally from about 0.01 to about 0.20 M, preferably from about 0.01 to about 0.08 M. The temperature of the reaction mixture may be from about 10° C. up to about 60° C., preferably between about 40° C. and about 45° C. At the lower temperatures, the solubility of the glucosyl acceptors and donors is decreased thus resulting in lower yields of the desired derivative. At higher temperatures, significant non-enzymatic hydolysis of the glycoside bond may occur, thus decreasing the yield. Above about 60° C., denaturation of the glucanotransferase enzyme may occur.
The reaction is generally conducted in aqueous solutions, however, the reaction solutions may contain minor concentrations of non-deleterious water-miscible organic solvents, such as ethanol, acetone, dioxane, and the like. The incorporation of such water miscible organic solvents may be used to increase the solubility of one or more reactants.
After completion of the reaction, the reaction is terminated by any suitable means. For example, the reaction may be terminated by denaturation of the glucanotransferase enzyme by adjustment of the pH of the incubation mixture to about 1.8 to about 2.5, preferably to about 2.0 to about 2.1, using any suitable mineral acid, and heating rapidly to 80° C. to 85° C. After about 2 to 3 minutes at this temperature, the mixture is chilled rapidly to room temperature.
Isolation of the desired maltooligosaccharide glycoside derivative from the reaction mixture may be accomplished by a variety of techniques. For instance, the derivative may be separated by precipitation with organic solvents, absorption or partition chromatography, selective crystallization, preparative HPLC, gel filtration chromotagraphy, or other conventional separation techniques.
The following isolation technique has been used for reaction mixtures wherein the glucosyl donor was α or β-cyclic dextrin, and the glucosyl acceptor was the p-nitrophenyl or 4-methylumbelliferyl glycosides:
1. The pH of the mixture is adjusted to 6-7 with sodium hydroxide and from 0.08 up to 0.20, preferably 0.12 ml of 1,1, 2,2-tetrachloroethane per ml of incubation mixture is added. The mixture is stirred vigorously for approximately 18 hours at 4° C. to precipitate unreacted α-cyclic dextrin. Other chlorinated hydrocarbons may be used as precipitants, but tetrachloroethane is preferable as it is more effective. 2. Precipitated α-cyclic dextrin is removed from the mixture, e.g., by filtration or centrifugation, and the filtrate or supernatant is deionized by passage through an adequate amount of a conventional mixed-bed ion-exchange resin, such as Amberlite® MB 3 resin. The effluent from the ion exchange column is evaporated to dryness, preferably by lyophilization. 3. Separation of the desired derivative from the reaction mixture may be achieved by conventional partition chromatography or by other chromatographic separation techniques. A convenient method is to dissolve the dried reaction mixture in water (or alcohol-water 50-60% V/V) and apply the sample to a column of microcrystalline cellulose equilibrated with 85:15 V/V 95% ethanol:water. Smaller maltooligosaccharide glycoside derivatives are eluted by washing with 85% etanol and may be collected. The maltoheptaoside derivatives are eluted with 70% ethanol, and the product collected. 4. After removal of ethanol by evaporation in vacuo, the syrup is dissolved in water and lyophilized. Yields of maltoheptaoside derivatives produced and isolated by this technique range from about 25-30% of theoretical, based upon the amount of glucosyl acceptor used in the reaction.
Having generally described the invention, a more complete understanding can be obtained by reference to certain specific examples, which are included for illustrative purposes only and are not intended to be limiting unless otherwise specified.
In the examples, the materials and analytical techniques used were as follows. Determination of oligosaccharide derivatives by high performance liquid chromatography (HPLC): Separation was achieved using a Laboratory Data Control liquid chromatograph equipped with a Carbohydrate column (Wates Associates, P/N L84038). The instrument was programmed for an exponentially increasing flow from 1.0 ml/min. to 4.0 ml/min during 10 min elution using the Exp 3 setting. The derivatives were eluted with 78:22 V/V acetonitrile:H 2 O. Peak heights at 280 nm were proportional to the height of a given compound, but the peak height for different compounds were not equivalent. The amount of compound corresponding to give peak height was determined by collecting the various peaks and determining the amount of p-nitrophenol or of 4-methylumbelliferone in the peak.
Assay of glucanotransferase enzyme: The activity was determined by a modification of the method of Hale and Rawlins (Cereal Chem. 28, 49, 1951) calcium acetate-acetic acid buffer, 0.50 ml, pH 5.2, and 5.0 ml of a 0.50% soluble starch solution (Lintner) was brought to 40° C. and 2.0 ml of a sample suitably diluted with water was added. After incubation for 20 min, 0.20 ml of the incubate was withdrawn and added to a mixture containing 2.5 ml of 0.035 M I 2 in 0.25 M KI, and 0.10 ml of 0.10 M H 2 SO 4 . After dilution with 5.0 ml of H 2 O the absorbance was determined at 660 nm. A reagent blank consisting of starch, buffer, and H 2 O rather than glucanotransferase was included. The difference in absorbance between the reagent blank and the incubation containing the glucanotransferase was proportional to the enzyme activity. A Unit of activity is defined as that amount of glucanotransferase which will cause a decrease in absorbance of 1.00 when measured during zero-order kinetics.
EXAMPLE I
This experiment was designed to determine the preferred ranges of glucosyl donor concentration, glucosyl acceptor concentration and reaction time for the maximum yield of the p-nitrophenyl maltoheptaoside. In the experiment, αcyclic dextrin and p-nitrophenyl-α-D-glycoside were dissolved in 9.5 ml of 0.077 M sodium acetate buffer, pH 5.2 containing 8 units of glucanotransferase isolated from Bacillus macerans, and the incubation was conducted at 40° C. Samples were taken at the intervals indicated on Table 1, the oligosaccharides were separated by HPLC, and the amounts of the maltooligosaccharides formed in such intervals were determined. The results of the experiment indicate that the yield of maltoheptaoside is highly dependent upon the reactant concentrations and the reaction time.
TABLE 1______________________________________MALTO-OLIGOSAC-CHARIDEDERIVATIVE TIME(mg)* 5' 10' 20' 30' 45' 60' 270'______________________________________A. 750 mg α-cyclic dextrin; 40 mg p-NO.sub.2 -phenylglycosideG.sub.4 .25 .67 1.2 2.1 2.7 2.9G.sub.5 .73 1.2 2.4 3.0 4.0 4.2G.sub.6 .17 1.2 2.5 3.0 3.4 3.7G.sub.7 24.5 40.3 53.3 54.7 48.4 37.4B. 750 mg α-cyclic dextrin; 80 mg p-NO.sub.2 -phenylglycosideG.sub.4 .59 1.0 1.7 2.9 4.6 6.7 18G.sub.5 .36 1.8 4.6 6.3 9.7 12.7 21.6G.sub.6 .34 1.4 3.4 5.6 10.5 11.9 19.5G.sub.7 31.7 53.3 85 96.5 102 102 35.1C. 750 mg α-cyclic dextrin; 160 mg p-NO.sub.2 -phenylglycosideG.sub.4 .84 1.2 2.4 3.5 5.8 9.2G.sub.5 1.2 2.4 5.2 7.9 13.0 19.2G.sub.6 .85 1.6 4.2 6.4 10.8 15.6G.sub.7 31.7 49.5 80.6 90 107 115D. 325 mg α-cyclic dextrin; 80 mg p-NO.sub.2 -phenylglycosideG.sub.4 .42 1.0 3.4 5.7 6.7 9.4G.sub.5 1.5 3.6 8.3 9.7 14.7 19.2G.sub.6 1.2 12.4 5.8 7.6 11.0 13.5G.sub.7 24.5 40.3 49.0 49.0 46.1 43.2E. 1500 mg α-cyclic dextrin; 80 mg p-NO.sub.2 -phenylglycosideG.sub.4 .59 .67 .83 1.5 2.4 4.2G.sub.5 .97 1.1 1.8 3.3 4.7 6.1G.sub.6 .34 .50 1.35 2.54 4.2 4.1G.sub.7 26.5 51.8 78.3 97.3 117 115______________________________________ *The abbreviations G.sub.4 -G.sub.7 indicate the maltooligosaccharide derivatives with 4 to 7 glucosyl units, respectively.
EXAMPLE II
Preparation of pNO 2 -phenyl-α-D-maltoheptaoside
Reaction conditions were chosen to give high yields of the desired p-NO 2 -phenyl-α-D-maltoheptaoside. Incubation of 15.0 g of α-cyclic dextrin, 1.60 g of p-NO 2 -phenyl-α-D-glycoside, and 156 units of glucanotransferase from Bacillus macerans in 60 ml of 0.083 M sodium acetate buffer, pH 5.2, was continued for 25 min at 40° C. The pH of the reaction mixture was adjusted to 2.0 with 1.0 M HCl, the acidified mixture was heated to 80°-82° C. for 2 min and cooled to room temperature. After adjustment of the pH to 6-7 with 1.0 M NaOH 7.0 ml of 1,1,2,2-tetrachloroethane was added to precipitate excess α-cyclic dextrin. The mixture was stirred at 40° C. for 18 hr, the precipitate was removed by filtration, and the filtrate was deionized by passage through a 60 ml bed volume of Amerberlite®-MB-3resin. The ion exchange resin was washed with H 2 O to obtain complete recovery of the desired product. The solution was lyophilized. Separation of the p-NO 2 -phenyl-α-D-maltoheptaoside from the dried mixture was conveniently accomplished by partition chromatography on a column of microcrystalline cellulose (Sigmacell® Type 50), 2.5×45 cm. The column was equilibrated with 85:15 V/V 95% ethanol:H 2 O, and the sample dissolved in 10 ml of 60% ethanol was applied to the column. The column was washed with 85% ethanol:H 2 O to remove unreacted p-NO 2 -phenyl-α-D-glycoside and other contaminating p-NO 2 -phenyl-α-D-glycosides formed by the action of glucanotransferase. The desired product, p-NO 2 -phenyl-α-D-maltoheptaoside was eluted from the column by 70% ethanol:H 2 O. The compound was collected, ethanol was removed by evaporation in vacuo, the syrup was dissolved in H 2 O and lyophilized. Yield of p-NO 2 -phenyl-α-D-maltoheptoaside was 1.60 gm. The purity of the compound by HPLC was in excess of 95%.
EXAMPLE III
Preparation of p-NO 2 -phenyl-β-D-maltoheptaoside
Reaction conditions were chosen to give high yields of the desired p-NO 2 -phenyl-α-D-maltoheptaoside. Incubation of 9.4 g of α-cyclic dextrin, 0.80 g of p-NO 2 -phenyl-β-glycoside, and 64 units of glucanotransferase from Bacillus macerans in 60 ml of 0.083 M sodium acetate buffer, pH 5.2 was continued for 30 min. Isolation of the desired product was accomplished by the procedures and techniques described in Example II. Yield of p-NO 2 -phenyl-β-maltoheptaoside was 0.60 g. Purity by HPLC was in excess of 95%.
EXAMPLE IV
Preparation of 4-methylumbelliferyl-α-D-maltoheptaoside
Reaction conditions were chosen to give high yields of the desired 4-methylumbelliferyl-α-D-maltoheptaoside. Incubation of 26.0 g of αcyclic dextrin, 0.467 g of 4-methylumbelliferyl-α-D-glycoside, and 71 units of glucanotransferase from Bacillus macerans in 260 ml of 0.01 M sodium acetate buffer, pH 5.2, was continued for 45 min at 40° C. Isolation of the desired product was accomplished by the procedures and techniques described in Example II. Yield of 4-methylumbelliferyl-α-D-maltoheptaoside was 0.576 g. The purity of HPLC was in excess of 95%.
EXAMPLE V
Preparation of 4-methylumbelliferyl-β-D-maltoheptaoside
Reaction conditions are chosen to give high yields of the desired 4-methylumbelliferyl-β-D-maltoheptaoside. Incubation of 26 g of α-cyclic dextrin, 0.467 g of 4-methylumbelliferyl-β-D-glycoside, and 71 Units of glucanotransferase from Bacillus macerans in 260 ml of 0.01 M sodium acetate buffer, pH 5.2, is continued for 45 min at 40° C. Isolation of the desired product is accomplished by the procedures and techniques described in Example II. The example should yield 4-methylumbelliferyl-β-D-maltoheptoaside in high purity.
EXAMPLE VI
Simultaneous preparation of phenolphthalyl-α-D-maltopentaoside and phenolphthalyl-α-D-maltotetraoside
Reaction conditions are chosen to give high yields of the desired maltooligosaccharide glycoside derivatives. Incubation of 0.5 g of linear oligosaccharide (DP-5 to DP-10, as discussed by L. M. Hall, U.S. Pat. No. 4,081,326), 0.08 g of phenolphthalyl-α-D-glycoside, and 8 units of glucanotransferase from Bacillus stearothermophilus in 5.0 ml of 0.10 M sodium acetate buffer, pH 5.2, is continued for 110 min at 40° C. Following denaturation of the enzyme, isolation of the desired products is accomplished by partition chromatography as described in Example II. The experiment should yield approximately equal quantities of phenolphthalyl-α-D-maltopentaoside and phenolphthalyl-α-D-maltotetraoside in high purity.
EXAMPLE VII
Preparation of Bacillus macerans amylase
A culture of Bacillus macerans (ATCC 8517) in 2000 ml of H 2 O containing 2% CaCO 3 and 10% wet weight of potato slices was maintained at 38° C. to 40° C. for four weeks. The culture was centrifuged at 5000 xg and adjusted to 90% saturation with ammonium sulfate at 4° C. The precipitate was collected by centrifugation, dissolved in 0.02 M piperazine-HCl buffer, pH 6.2 to a final volume of 75 ml. The amylase was precipitated at 35% saturation of ammonium sulfate, dissolved in 13 ml of piperazine buffer (0.02 M, pH 6.2) and dialyzed vs the same buffer for 24 hours. The dialyzed sample was applied to DEAE cellulose, 2.5×45 cm, equilibrated with the 0.02 M piperazine buffer. The enzyme was eluted from the DEAE by 500 ml of a linear gradient of 0.02 M to 0.52 M Cl - using NaCl in the 0.02 M piperazine buffer, pH 6.2. Fractions containing enzymatic activity were combined and used in preceding examples I-V. There was no detectasble hydrolytic activity in the resulting enzyme product.
EXAMPLE VIII
This experiment was conducted to determine the utility of substrates produced by the present method in the amylase assay procedures described by Driscoll, et al. in U.S. Pat. No. 4,102,747. Amylase activity was measured in a test solution containing the following components: phosphate buffer 0.1 M, pH 7.1; NaCl 0.05 M; Maltase (prepared in accordance with Hall, L. M. U.S. Pat. No. 4,071,407), 300 Units/ml; and p-Nitrophenyl-α-D-maltoheptaoside, 2.5 mg/ml.
Amylase activity was detected at 405 nm at 37° C. Amylase activity was expressed as the rate of change of absorbance per minute resulting from the formation of p-nitrophenol caused by the enzymatic action of amylase on the substrate. The rate of formation of p-nitrophenol in the absence of amylase was insignificant. Sixty-seven serum samples were analyzed by the foregoing procedure and also by the α-Amyl Amylase procedure (available from the Dade Division of American Hospital Supply Corporation). Correlation between the two methods was excellent, with a correlation coefficient (r) of 0.969.
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Disclosed herein is a method for producing maltooligosaccharide glycosides in substantially pure form which includes the steps of incubating a glucosyl donor and a glucosyl acceptor in the presence of a glucanotransferase enzyme under transglycosylating conditions and separating the maltooligosaccharide glycoside from the reaction mixture.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a stable coal-in-hydrocarbon oil suspension containing coal, hydrocarbon oil, water and the product resulting from the reaction of (1) polycyclic, polycarboxylic acids obtained as a result of the oxidation of coal with (2) a base and to a process for preparing such suspension.
2. Description of the Prior Art
Coal-in-oil suspensions can be used, for example, as fuel mixtures, in pipe line transportation of coal, etc. It is an object herein to provide a stable coal-in-oil suspension prepared using a highly effective dispersing agent that is inexpensive and is stable in storage.
SUMMARY OF THE INVENTION
We have prepared stable coal-in-oil suspensions using as an inexpensive dispersing agent therefor the product resulting from the reaction of (1) polycyclic, polycarboxylic acids obtained as a result of the oxidation of coal with (2) a base.
In preparing the stable suspensions herein we require only four components: a hydrocarbon oil, coal, water and the product resulting from the reaction of (1) polycyclic, polycarboxylic acids obtained as a result of the oxidation of coal with (2) a base.
Any kind of hydrocarbon oils, such as crude oil, heavy oil, gas oil, gasoline, oils resulting from coal liquefaction or other coal conversion processes, the extract from oil shale and tar sands, liquids resulting from the pyroylsis of organic matter, etc., can be used as a component of the novel suspensions herein.
Any suitable or conventional coal can be used herein in the preparation of the defined suspensions. For example, any of the coals defined hereinafter as being suitable for the preparation of the polycyclic, polycarboxylic acids can be employed. The size of the coal particles can vary over a wide range, for example, from particles whose average length can be as about one inch (2.54 centimeters), or more, to as small as about 500 mesh, although, in general the average length will probably be no longer than about one-half inch (1.27 centimeters) but no smaller than about 200 mesh.
The polycyclic, polycarboxylic acids employed in the reaction with a base to obtain the product used to prepare the suspensions herein can be obtained by any conventional or suitable procedure for the oxidation of coal. Bituminous and subbituminous coals, lignitic materials and other types of coal products are exemplary of coals that are suitable herein. Some of these coals in their raw state will contain relatively large amounts of water. These can be dried prior to use, if desired, and preferably can be ground in a suitable attrition machine, such as a hammermill, to a size such that at least about 50 percent of the coal will pass through a 40-mesh (U.S. Series) sieve. The carbon and hydrogen content of the coal are believed to reside primarily in multi-ring aromatic and non-aromatic compounds (condensed and/or uncondensed), heterocyclic compounds, etc. On a moisture-free, ash-free basis the coal can have the following composition:
TABLE I______________________________________ Weight Percent Broad Range Preferred Range______________________________________Carbon 45-95 60-85Hydrogen 2.2-8 5-7Oxygen 2-46 8-40Nitrogen 0.7-3 1-2Sulfur 0.1-10 0.2-5______________________________________
Any conventional or suitable oxidation procedure can be used to convert the coal to the desired polycyclic, polycarboxylic acids. For example, a stirred aqueous slurry containing coal in particulate form, with or without a catalyst, such as cobalt, manganese, vanadium, or their compounds, can be subjected to a temperature of about 60° to about 225° C. and an oxygen pressure of about atmospheric (ambient) to about 2000 pounds per square inch gauge (about atmospheric to about 13.8 MPa) for about one to about 20 hours. The product so obtained can then be subjected to mechanical separation, for example filtration, and solid residue can be washed with water, if desired, and dried. The solid product remaining will be a mixture of water-insoluble polycyclic, polycarboxylic acids, hereinafter referred to as "water-insoluble coal carboxylate". A preferred procedure for preparing such coal carboxylate involves subjecting a slurry containing coal in particulate form to oxidation with nitric acid. An exemplary procedure for so converting coal to coal carboxylate is disclosed, for example, in U.S. Pat. No. 4,052,448 to Schulz et al. Thus, a slurry containing coal can be subjected to reaction with aqueous nitric acid having a concentration of about one to about 90 percent, preferably about three to about 70 percent, by weight at a temperature of about 15° to about 200° C., preferably about 25° to about 100° C., and a pressure of about atmospheric to about 2000 pounds per square inch gauge (about atmospheric to about 13.8 MPa), preferably about atmospheric to about 500 pounds per square inch gauge (about atmospheric to about 3.5 MPa), for about five minutes to about 15 hours, preferably about two to about six hours. The oxidation with nitric acid, can, if desired, be carried out in an atmosphere containing molecular oxygen, as, for example, in U.S. Patent Applications Ser. Nos. 923,953 and 924,054, filed July 12, 1978 of Schulz et al. The resulting product is then subjected to mechanical separation, for example, filtration, and the solid residue can be washed with water, if desired, and dried to produce the water-soluble coal carboxylate.
The entire mixture of water-insoluble coal carboxylate so obtained, or any portion thereof, can be used in the reaction with a base herein, if desired. An example of a portion of the entire mixture of water-insoluble coal carboxylate that can be used in the reaction with a base is the extract obtained as a result of the extraction of the entire mixture of water-insoluble coal carboxylate with a polar solvent as defined in U.S. Pat. No. 4,052,448 to Schulz et al. Another example of a portion of the water-insoluble coal carboxylate that can also be reacted with a base herein is that portion of the water-insoluble coal carboxylate that is insoluble in a polar solvent as defined in U.S. Pat. No. 4,147,882 to Schulz et al. Still another example of polycyclic, polycarboxylic acids that can be reacted with a base herein are the water-soluble polycylcic, polycarboxylic acids present in the filtrate obtained when coal is oxidized and the resulting product is subjected to filtration, as for example, the water-soluble, polar solvent-soluble carboxylic acids obtained in U.S. Pat. No. 4,137,418 to Schulz et al. These can be referred to as "water-soluble coal carboxylate" . For simplicity, all of these acids can be referred to as "coal carboxylate".
The individual components of the coal carboxylate are believed to be composed of condensed and/or non-condensed aromatic and non-aromatic rings, with an average number of such rings in the individual molecules ranging from about one to about ten, but generally from about two to about eight. On the average it is believed the number of carboxyl groups carried by the individual molecules will range from about two to about eight, generally from about three to about eight. The average molecular weight can range from about 200 to about 3000, but generally can be from about 300 to about 3000 and the average neutral equivalent from about 50 to about 900, generally from about 70 to about 600. A typical analysis of the coal carboxylates on a moisture-free and ash-free basis that will be reacted with the base herein is set forth below in Table II.
TABLE II______________________________________ Weight Percent Broad Range Preferred Range______________________________________Carbon 35 to 65 37 to 62Hydrogen 1 to 5 3 to 5Nitrogen 1 to 6 3 to 6Oxygen 20 to 60 30 to 50Sulfur 0.1 to 8 0.1 to 5______________________________________
Any base, including the corresponding or basic salt, organic or inorganic, that can react with an acid can be used herein to react with the coal carboxylate. Thus, hydroxides of the elements of Group IA and Group IIA of the Periodic Table can be used. Of these we prefer to use potassium, sodium or calcium hydroxide. In addition ammonium hydroxide can also be used. Among the organic bases that can be used are aliphatic amines having from one to 12 carbon atoms, preferably from one to six carbon atoms, such as methylamine, ethylamine, ethanolamine and hexamethylenediamine, aromatic amines having from six to 60 carbon atoms, preferably from six to 30 carbon atoms, such as aniline and naphthylamine, aromatic structures carrying nitrogen as a ring constituent, such as pyridine and quinoline, etc. By "basic salt" we mean to include salts of the elements of Groups IA and IIA of the Periodic Table whose aqueous solutions exhibit a pH in the base region, such as potassium carbonate, sodium metasilicate, calcium acetate, barium formate, etc.
The reaction between the coal carboxylate and the base is easily effected. The amounts of reactants are so correlated that the amount of base used is at least that amount stoichiometrically required to react with all, or a portion (for example, at least about 10 percent, preferably at least about 50 percent), of the carboxyl groups present in the coal carboxylate. This can be done, for example, by dispersing the coal carboxylate in an aqueous medium, such as water, noting the initial pH thereof, adding base thereto while stirring and continuing such addition while noting the pH of the resulting mixture. Such addition can be stopped anytime. In the preferred embodiment wherein a large portion or substantially all of the carboxyl groups are desirably reacted with the base, addition of base is continued until a stable pH reading is obtained. The reactions can be varied over a wide range, for example, using a temperature of about 5° to about 150° C., preferably about 15° to about 90° C., and a pressure of about atmospheric to about 75 pounds per square inch gauge (about atmospheric to about 0.5 MPa), preferably about atmospheric (about 0.1 MPa). The resulting product can then be subjected, for example, to a temperature of about 20° to about 200° C. under vacuum to about 100 pounds per square inch qauge (under vacuum to about 0.69 MPa) for the removal of water therefrom. However, if desired the water need not be removed from the total reaction product and the total reaction product, or after removal of a portion of the water therefrom, can be used to prepare the emulsions as taught herein.
The amounts of each component present in the suspension prepared herein can be varied over a wide range. Thus, the weight ratio of coal to hydrocarbon oil can be in the range of about 1:5 to about 3:1, preferably in the range of about 1:2 to about 2:1. The weight ratio of water to hydrocarbon oil can be in the range of about 1:1 to about 0.01:1, preferably in the range of about 0.5:1 to about 0.05:1. The amount of dispersing agent used, that is, the product resulting from the reaction of coal carboxylate with a base, on a weight basis, relative to water, can be in the range of about 1:199 to about 1:3, preferably about 1:49 to about 1:4.
The suspensions defined and claimed herein are easily prepared. A convenient procedure involves introducing the dispersing agent into water, while mixing, for a time sufficient to dissolve and/or disperse the dispersing agent therein, for example, for a period of about 0.01 to about four hours. If desired, the dispersing agent can be prepared in situ by separately introducing into the water the coal carboxylate and base and following the procedure hereinabove defined. To the mixture so prepared there is then added oil and coal, with mixing of the resulting mixture being continued, for example, from about 0.01 to about 10 hours, sufficient to obtain the desired suspension. Mixing can be effected in any suitable manner, for example, using propeller agitation, turbine agitation, colloid mill, etc. The suspensions so prepared are stable, that is, there is no separation of coal from oil and there is no settling of coal. When desired, however, the suspensions herein can easily be broken, for example, mechanically by bringing the same into contact with a body, for example, a filter, or chemically, for example, by contact with an acid solution, such as hydrochloric acid.
DESCRIPTION OF PREFERRED EMBODIMENTS
A mixture of polycyclic, polycarboxylic acids (Coal Carboxylate) was prepared as follows. To a one-gallon glass reactor equipped with a mechanical stirrer and heating and cooling coils there were charged 978 milliliters of water and 178.6 milliliters of 70 percent by weight aqueous nitric acid. The mixture was heated to 60° C., with stirring, and maintained at this temperature during the run. To the resulting mixture there was added a slurry comprised of 800 grams of North Dakota lignite and 800 milliliters of water over a one-hour period. The mixture was held at 60° C. for three hours, cooled to room temperature and then removed from the reactor and filtered. The recovered solids were washed three times with water (1000 cubic centimeters of water each time), dried in a vacuum oven, resulting in the production of 560 grams of particulate polycyclic, polycarboxylic acids. The North Dakota lignite used analyzed as follows: 33 weight percent water, 45.7 weight percent carbon, 2.8 weight percent hydrogen, 11.3 weight percent oxygen, 0.6 weight percent sulfur, 0.6 weight percent nitrogen and 6.0 weight percent metals.
A number of suspensions was prepared as follows. Into a Warning Blender there were placed water, coal carboxylate prepared above and pellets of sodium hydroxide. These materials were mixed at low speeds (about 500 RPM) for about five minutes, sufficient to obtain a reaction between the coal carboxylate and the base. To the resulting solution there was added particulate coal that had passed a 40-mesh (U.S. Series) sieve and an oil. The resulting mixture was mixed at high speed (about 20,000 RPM) for about 20 minutes, sufficient to obtain a uniform stable suspension. Three coals were used in the preparation of the suspensions. The English Rank 900 Coal analyzed as follows: 13.6 weight percent water, 63.6 weight percent carbon, 4.3 weight percent hydrogen, 12.9 weight percent oxygen, 1.2 weight percent sulfur, 1.3 weight percent nitrogen and 3.1 weight percent metals. Belle Ayre coal analyzed as follows: 19.0 weight percent water, 58.6 weight percent carbon, 3.84 weight percent hydrogen, 0.81 weight percent nitrogen, 1.21 weight percent oxygen, 0.43 weight percent sulfur and 6.25 weight percent metals. Kentucky No. 9 coal analyzed as follows: 1.1 weight percent water, 67.93 weight percent carbon, 4.83 weight percent hydrogen, 1.50 weight percent nitrogen, 13.03 weight percent oxygen, 4.34 weight percent sulfur and 7.37 weight percent metals. Three hydrocarbon oils were used. ATB is an atmospheric tower bottoms obtained from a Kuwait crude having an API Gravity of 15.9, a pour point of 7.2° C., viscosity at 98.9° C. (SUV) of 157.2 and an ash content of 0.003 weight percent. The No. 2 Fuel Oil had an API Gravity of 33, a viscosity at 37.8° C. (SUV) of 35.3, a pour point of -18° C. and ash content of 0.003 weight percent. The No. 6 Fuel Oil had an API Gravity of 10.6, a viscosity at 37.8° C. (SUV) of 4450 and at 98.9° C. of 153, a pour point of 0° C. and an ash content of 0.02 weight percent. The suspensions so prepared were examined at various intervals of time for stability by noting whether or not separation of coal and water, oil and water or coal and oil had occurred, that is, whether any appreciable settling had occurred. The data obtained are tabulated below in Table III.
TABLE III__________________________________________________________________________ Grams of Grams Water Grams of Grams Sta-ExampleHydrocarbon Hydrocarbon Coal of in Coal of bility,No. Oil Oil Suspended Coal Grams Carboxylate NaOH Days.sup.(1)__________________________________________________________________________I ATB 200 Belle Ayre 100 150 10 5 42II No. 2 Fuel Oil 100 Kentucky 98.9 101.1 15 7.5 30 No. 9III No. 2 Fuel Oil 200 Kentucky 197.8 22.2 20 10 16 No. 9IV No. 2 Fuel Oil 200 Kentucky 197.8 152.2 20 10 16 No. 9V No. 2 Fuel Oil 200 Kentucky 98.9 101.1 20 10 16 No. 9VI No. 2 Fuel Oil 200 Kentucky 197.8 22.2 10 5 16 No. 9VII No. 2 Fuel Oil 200 Kentucky 98.9 101.1 5 2.5 6 No. 9VIII No. 2 Fuel Oil 200 English 200 131.5 5 2.5 5 Rank 900IX No. 6 Fuel Oil 200 English 200 71.5 5 2.5 5 Rank 900__________________________________________________________________________ .sup.(1) Last day of observation; suspensions still stable.
The data in Table III above clearly exemplifies the stability of the coal-in-oil suspensions claimed herein.
Obviously, many modifications and variations of the invention, as hereinabove set forth, can be made without departing from the spirit and scope thereof and therefore only such limitations should be imposed as are indicated in the appended claims.
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A suspension containing coal, hydrocarbon oil, water and the product resulting from the reaction of (1) polycyclic, polycarboxylic acids obtained as a result of the oxidation of coal with (2) a base. The process for preparing such suspension is also claimed.
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BACKGROUND OF THE INVENTION
The present invention relates to a novel Interleukin-1 production inhibiting compound which is produced from a microorganism belonging to the genus Streptomyces, and which is useful as an agent for treating diseases such as chronic rheumatism, gout, osteoarthritis, osteoporosis, periarteritis nodosa, ulcerative colitis, chronic nephritis, active chronic hepatitis, septicemia, endotoxin shock, atherosclerosis, pyrexia of infectious disease and the like and as an antibacterial agent.
Interleukin-1 (hereinafter referred to as "IL-1") is a protein which is produced from a variety of in vivo cells such as macrophage, monocyte, neutrophil, fibroblast, skin keratinocyte, hepatic Kupffer cell, renal glomerular mesangial cell, brain astroglia, angioendothelial cell and the like and which has a molecular weight of 17.5 kDa. IL-1 includes α-form having an isoelectric point (pI) of 5 and β-form having pI of 7. At present, it has been clarified that the α-form and β-form exhibit the same activity.
IL-1 is known to have various biological activities. That is, IL-1 is deemed to act as a factor that enhances multiplicative division of lymphocytes and as a cofactor that enhances multiplication of B cells and production of antibodies. Further, it is considered that IL-1 acts on arachidonic acid cascade in a temperature center of the hypothalamus to increase the synthesis of prostagrandin E 2 , thereby causing pyrexia. Still further, it is shown that the activity of IL-1 is significantly increased in the serum of patients suffering from septicemia or Crohn's disease and on a cavum articulare of patients who suffer from rheumatism. Thus, it is suggested that IL-1 be related with attack and progress of these diseases. Suppression of the production of IL-I is considered to be effective for alleviating the diseases that occur through IL-1.
As the compound that exhibits activity of inhibiting the production of IL-1, synthetic compounds such as naphthalene derivatives Japanese Published Unexamined Patent Application No. 59,743/1992!, 3-arylisothiazole derivatives Japanese Published Unexamined Patent Application No. 74,121/1992! and zingerol derivatives Japanese Published Unexamined Patent Application No. 202,127/1992! are known.
The following compounds are known to exhibit antibacterial activity.
Manumycin A having the following formula is known to exhibit antibacterial activity Tetrahedron Lett. 50, 4995 (1973)!. ##STR2##
Manumycins B, C and D having the following formulae are known to exhibit antibacterial activity J. Org. Chem. 58, 6583 (1993)!. ##STR3##
Manumycins E and G having the following formulae are known to exhibit antibacterial activity J. Antibiot. 47, 324, (1994)!. ##STR4##
U-56407 represented by the following formula is known to exhibit antibacterial activity J. Antibiotics, 36, 950-956 (1983)!: ##STR5##
Alisamycin represented by the following formula is known to exhibit antibacterial activity J. Antibiotics, 46, 1027-1030 (1990)!. ##STR6##
SUMMARY OF THE INVENTION
It is an object of the present invention to provide novel physiologically active substances that exhibit excellent inhibiting activity of the production of IL-1 as well as excellent antibacterial activity.
The present invention provides a compound hereinafter referred to as "Compound (I)"! represented by formula(I) ##STR7## wherein R represents 4-methyl-1-pentenyl, 5-methyl-1,3-heptadienyl or 1-methylpentanyl.
Compound (I) can be obtained by culturing a microorganism belonging to the genus Streptomyces.
DETAILED DESCRIPTION OF THE INVENTION
Among Compound (I), the compound in which R is 4-methyl-1-pentenyl is named EI-1511-3, the compound in which R is 5-methyl-1,3-heptadienyl EI-1511-5, and the compound in which R is 1-methylpentyl EI-1625-2, respectively. The structural formulae and physicochemical properties of these compounds are described below.
(i) EI-1511-3 ##STR8## State: Yellow powder Melting point: 165°-168° C.
Specific rotation: α! D 27 =+231° (c=0.225, CH 3 OH)
FABMS spectrum: m/z amu 495 (M+H) +
High-resolution FABMS spectrum: m/z amu 495.2124 (M+H) + , Δ-0.7 mmu C 27 H 31 N 2 O 7
UV spectrum (CH 3 OH): λ max nm (ε) 314 (42,600), 278 (58,600).
CD spectrum (CH 3 OH): λ max nm (Δε) 314 (+14.17), 280 (-19.93).
IR spectrum (KBr): υ max cm -1 3379, 1684, 1672, 1616, 1523, 1367, 1001.
1 H-NMR spectrum (CDCl 3 ): δ ppm (integration, multiplicity, binding constant)
13.50 (1H, br. s), 7.56 (1H, br. s), 7.55 (1H, br. s), 7.41 (1H, d, J=2.7 Hz), 7.33 (1H, dd, J=14.8, 11.2 Hz), 7.24 (1H, dd, J=14.8, 10.1 Hz), 6.59 (2H, m), 6.42 (1H, m), 6.15 (2H, m), 6.05 (1H, d, J=14.8 Hz), 5.87 (1H, m), 5.84 (1H, d, J=14.8 Hz), 3.71 (1H, dd, J=3.8, 2.7 Hz), 3.65 (1H, d, J=3.8 Hz), 3.00 (1H, br. s), 2.61 (2H, m), 2.53 (2H, m), 2.07 (2H, dd, J=6.4, 6.4 Hz), 1.72 (1H, m), 0.91 (6H, d, J=6.7 Hz).
13 C-NMR spectrum (CDCl 3 ): δ ppm (multiplicity)
197.26 (s), 188.62 (s), 173.82 (s), 165.43 (s), 165.17 (s), 144.28 (d), 143.75 (d), 143.56 (d), 139.62 (d), 136.24 (d), 131.76 (d), 131.65 (d), 129.11 (d), 128.16 (s), 126.29 (d), 121.55 (d), 120.94 (d), 114.93 (s), 71.25 (s), 57.46 (d), 53.02 (d), 42.41 (t), 32.14 (t), 28.33 (d), 25.64 (t), 22.37 (q), 22.37 (q).
Solubility: easily soluble in dimethyl sulfoxide and acetone, soluble in methanol
Color reaction: positive for iodine and sulfuric acid
(ii) EI-1511-5 ##STR9## State: Yellow powder Melting point: 194°-197° C.
Specific rotation: α! D 26 =+325° (c=0.147, CH 3 OH)
FABMS spectrum: m/z amu 521 (M+H) +
High-resolution FABMS spectrum: m/z amu 521.2289 (M+H) + , Δ+0.2 mmu C 29 H 33 N 2 O 7
UV spectrum (CH 3 OH): λ max nm (ε) 309 (50,300).
CD spectrum (CH 3 OH): λ max nm (Δε) 342 (+38.74), 300 (-52.86).
IR spectrum (KBr): υ max cm -1 3313, 1687, 1653, 1620, 1608, 1539, 1527, 1371, 1001.
1 H-NMR spectrum (CDCl 3 ): δ ppm (integration, multiplicity, binding constant)
13.51 (1H, br. s), 7.56 (2H, br. s), 7.41 (1H, d, J=2.7 Hz), 7.33 (1H, dd, J=14.7, 11.3 Hz), 7.29 (1H, dd, J=15.0, 11.3 Hz), 6.59 (2H, m), 6.56 (1H, dd, J=15.0, 10.5 Hz), 6.42 (1H, m), 6.23 (1H, dd, J=15.0, 11.3 Hz), 6.11 (1H, dd, J=15.2, 10.5 Hz), 6.05 (1H, d, J=14.7 Hz), 5.89 (1H, d, J=15.0 Hz), 5.86 (1H, m), 5.84 (1H, dd, J=15.2, 7.9 Hz), 3.71 (1H, dd, J=3.8, 2.7 Hz), 3.65 (1H, d, J=3.8 Hz), 3.01 (1H, br.s), 2.61 (2H, m), 2.53 (2H, m), 2.14 (1H, m), 1.36 (2H, dq, J=7.3, 7.3 Hz), 1.02 (3H, d, J=6.7 Hz), 0.87 (3H, t, J=7.3 Hz).
13 C-NMR spectrum (CDCl 3 ): δ ppm (multiplicity)
197.29 (s), 188.63 (s), 173.84 (s), 165.43 (s), 165.07 (s), 146.67 (d), 143.67 (d), 143.56 (d), 142.08 (d), 139.62 (d), 136.27 (d), 131.77 (d), 131.66 (d), 128.22 (d), 128.18 (s), 127.49 (d), 126.31 (d), 121.56 (d), 121.56 (d), 114.96 (s), 71.26 (s), 57.47 (d), 53.02 (d), 38.83 (d), 32.18 (t), 29.54 (t), 25.67 (t), 19.73 (q), 11.74 (q).
Solubility: easily soluble in dimethyl sulfoxide and acetone, soluble in methanol
Color reaction: positive for iodine and sulfuric acid
(iii) EI-1625-2 ##STR10## State: Yellow powder Melting point: 105°-107° C.
Specific rotation: α! D 29 =-17.0° (c=0.1, CHCl 3 )
Molecular formula: C 27 H 32 N 2 O 7
FABMS spectrum: m/z amu 497 (M+H) +
High-resolution FABMS spectrum: calculated C 27 H 33 N 2 O 7 : 497.2288, found 497.2277
UV spectrum (CH 3 OH) : λ max nm (ε) 321 (37,600), 281 (32,400), 265 (31,000).
CD spectrum (CH 3 OH): λ ext nm (Δε) 322 (-3.7), 277 (+9.9).
IR spectrum (KBr): υ max cm -1 3317, 2925, 1674, 1624, 1522, 1367, 1005.
1 H-NMR spectrum (CDCl 3 ): δ ppm (integration, multiplicity, binding constant)
13.57(1H, br. s), 7.70(1H, s), 7.56 (1H, s), 7.40 (1H, d, J=2.5 Hz), 7.32(1H, dd, J=11.0, 14.6 Hz), 6.82 (1H, dd, J=8.1, 15.4 Hz), 6.59(2H, m), 6.41 (1H, m), 6.08 (1H, d, J=14.6 Hz), 5.85(1H, m), 5.81(1H, d, J=15.4 Hz), 3.70(1H, dd, J=2.5, 3.7 Hz), 3.64(1H, d, J=3.7 Hz), 3.32(1H, br.s), 2.59(2H, br. s), 2.54(2H, br. s), 2.30(1H, m), 1.40-1.31(2H, m), 1.30-1.19(4H, m), 1.05(3H, d, J=6.8 Hz), 0.88(3H, t, J=6.8 Hz).
13 C-NMR spectrum (CDCl 3 ): δ ppm (multiplicity)
197.4(s), 188.7(s), 174.1(s), 165.5(s), 165.0(s), 153.4(d), 143.5(d), 139.6(d), 136.3(d), 131.8(d), 131.6(d), 128.0(s), 126.7(d), 121.6(d), 121.5(d), 115.0(s), 71.2(s), 57.4(d), 53.0(d), 36.6(d), 35.8(t), 32.2(t), 29.4(t), 25.7(t), 22.7(t), 19.5(q), 14.0(q).
Rf values of Compounds (I) obtained by thin-layer chromatography under the following conditions are shown below.
Rf values:
EI-1511-3: 0.57
EI-1511-5: 0.60
EI-1625-2: 0.57
Eluent: chloroform-methanol-acetic acid (90:10:1) Thin layer: HPLC Fertigplatten Kieselgel 60 F254 (Merck Co.)
Elution method: room temperature, rising mode, 20 to 40 minutes
Detection: irradiation with UV light of 253.6 nm
As apparent from the above-mentioned data, Compound (I) of the present invention is novel.
The above-mentioned data were obtained using the following instruments.
Melting point: Yanagimoto instrument for measuring the melting point of a trace amount of a sample
Specific rotation: JASCO DIP-370-model digital polarimeter
IR spectrum: JEOL JIR-RFX3001-model IR-absorption spectrophotometer
UV spectrum: SHIMADZU UV-2200-model UV-absorption spectrophotometer
CD spectrum: JASCO J-500A-model circular dichroism spectrophotometer
Mass spectrum: JEOL HX110A-model mass spectrometer
NMR spectrum: JEOL α400-model nuclear magnetic resonance meter
A process for producing Compound (I) is described below.
Compound (I) is produced by cultivating in a culture medium a microorganism belonging to the genus Streptomyces which has the ability to produce Compound (I), accumulating Compound (I) in the culture, and recovering Compound (I) from the culture.
As the microorganism having the ability to produce Compound (I), any strain of the genus Streptomyces can be used so long as the strain has the ability to produce Compound (I). Further, mutants obtained by mutagenizing these strains either spontaneously or artificially, for example, through irradiation with an ultraviolet light, irradiation with X-rays or treatment with a mutation inducer are also available so long as the mutants have the ability to produce Compound (I).
Specific examples thereof include Streptomyces sp. E-1511 strain and Streptomyces sp. E-1625 strain.
The bacteriological properties of Streptomyces sp. E-1511 strain are described below.
1. Morphological properties
1) Hyphae
Formation of aerial hyphae: Observed
Fragmentation and motility of aerial hyphae: Not observed
Fragmentation and motility of substrate hyphae: Not observed
2) Spores
Sporulation and positions to which spores adhere: Sporulated as aerial spores
Formation of sporangia and positions to which sporangia adhere: Not observed
Number of spores linked on a sporophore: 10 or more
Morphology of many spores linked: Curved or spiral
Characteristics of spores
Surface structure: Smooth
Shape and size: Rod, approximately 0.6 to 0.8 μm ×0.7 to 0.9 μm
Motility and presence of flagella: Not observed
3) Others:
Chlamydospores: Not observed
Synnema: Not observed
Pseudosporangia: Not observed
Branching mode of hyphae: Simple branching
2. Cultural characteristics
E-1511 strain grows normally or abundantly on usual synthetic or natural media, and its substrate hyphae are brown or brownish gray. On some media, the strain produces brown soluble pigments.
The characteristics in the growth conditions and colors of the strain, when the strain was cultivated on various media at 28° C. for 14 days, are shown below. The colors were designated according to the classification of colors indicated in Color Harmony Manual published by Container Corporation of America, 4th edition (1958).
1) Sucrose-nitrate agar
Growth: Moderate
Color of substrate hyphae: Olive gray (11/2 ig)
Formation of aerial hyphae and Color thereof: Abundant, Beige gray (3 ih)
Soluble pigments: None
2) Glucose-asparagine agar
Growth: Abundant
Color of substrate hyphae: Mustard tan (2 lg) to mustard brown (2 ni)
Formation of aerial hyphae and Color thereof: Abundant, silver gray (3 fe)
Soluble pigments: Produced (brown)
3) Glycerol-asparagine agar
Growth: Abundant
Color of substrate hyphae: Clove brown (3 ni)
Formation of aerial hyphae and Color thereof: Abundant, silver gray (3 fe)
Soluble pigments: Produced (brown)
4) Starch-inorganic salt agar
Growth: Abundant
Color of substrate hyphae: Mustard brown (2 pl)
Formation of aerial hyphae and Color thereof: Abundant, Silver gray (3 fe)
Soluble pigments: Produced (brown)
5) Tyrosine agar
Growth: Abundant
Color of substrate hyphae: Mustardbrown (2 pi) to Clove brown (3 ni)
Formation of aerial hyphae and Color thereof: Abundant, Covert gray (2 fe)
Soluble pigments: Slightly produced (brown)
6) Nutrient agar
Growth: Moderate
Color of substrate hyphae: Mustard brown (2 pi)
Formation of aerial hyphae and Color thereof: Poor, Covert gray (2 fe)
Soluble pigments: None
7) Yeast extract-malt extract agar
Growth: Abundant
Color of substrate hyphae: Clove brown (3 pl)
Formation of aerial hyphae and Color thereof: Abundant, Silver gray (3 fe)
Soluble pigments: Produced (brown)
8) Oatmeal agar
Growth: Moderate
Color of substrate hyphae: Golden brown (3 pi) to Clove brown (3 pl)
Formation of aerial hyphae and Color thereof: Moderate, Ashes (5 fe)
Soluble pigments: Produced (brown)
3. Physiological properties:
The temperature range for growth indicates the results of the strain after 10-day cultivation. The remaining items indicate the results after a 2 to 3 week-cultivation at 28° C.
1) Temperature range for growth: 6.0° to 38.0° C.
2) Liquefaction of gelatin: Observed
3) Hydrolysis of starch: Observed
4) Coagulation of skim milk powder and peptonization thereof: Peptonized
5) Formation of melanoid pigment:
(i) Peptone-yeast extract-ion agar medium: Not observed
(ii) Tyrosine agar: Slightly formed
6) Utilization of carbon source (basic medium: Pridham Gottlieb-agar medium):
+ indicates that the strain utilizes the carbon source; - indicates that the strain did not utilize the carbon source; and W indicates that it is unclear as to whether or not the strain utilized the carbon source.
______________________________________ L-Arabinose: - D-Xylose: + D-Glucose: + Sucrose: W Raffinose: + D-Fructose: W L-Rhamnose: + Inositol: W D-Mannitol: W______________________________________
4. Chemotaxonomic properties:
Optical isomer of diaminopimelic acid in the strain: LL-form
Accordingly, the strain is classified into the genus Streptomyces of actinomycetes.
The strain was named Streptomyces sp. E-1511, and it was deposited at the National Institute of Bioscience and Human Technology of the Agency of Industrial Science and Technology under FERM BP-4792 as of Sep. 1, 1994 in terms of the Budapest Treaty.
The bacteriological properties of Streptomyces sp. E-1625 are described below.
1. Morphological properties
1) Hyphae
Formation of aerial hyphae: Observed
Fragmentation and motility of aerial hyphae: Not observed
Fragmentation and motility of substrate hyphae: Not observed
2) Spores
Sporulation and positions to which spores adhere: Sporulated as aerial spores
Formation of sporangia and positions to which sporangia adhere: Not observed
Number of spores linked on a sporophore: 10 or more
Morphology of many spores linked: Curved or spiral
Characteristics of spores
Surface structure: Smooth
Shape and size: Rod, approximately 0.6 to 0.7 μm ×0.7 to 0.9 μm
Motility and presence of flagella: Not observed
3) Others:
Chlamydospores: Not observed
Synnema: Not observed
Pseudosporangia: Not observed
Branching mode of hyphae: Simple branching
2. Cultural characteristics
E-1625 strain grows normally or abundantly on usual synthetic or natural media, and its substrate hyphae are brown to red. On some media, the strain produces brown soluble pigments.
The characteristics in the growth conditions and colors of the strain, when the strain was cultured on various media at 28° C. for 14 days, are shown below. The colors were designated according to the classification of colors indicated in Color Harmony Manual published by Container Corporation of America, 4th edition (1958).
1) Sucrose-nitrate agar
Growth: Moderate
Color of substrate hyphae: Sand (2 ec)
Formation of aerial hyphae and Color thereof: Abundant, Pussywillow gray (5 dc) to ashes (5 fe)
Soluble pigments: Slightly produced (brown)
2) Glucose-asparagine agar medium
Growth: Abundant
Color of substrate hyphae: Dusty yellow (11/2 gc) to Rast tan (5 le)
Formation of aerial hyphae and Color thereof: Abundant, Natural (3 dc) to ashes (5 fe)
Soluble pigments: Produced (yellow)
3) Glycerol-asparagine agar medium
Growth: Abundant
Color of substrate hyphae: Dusty yellow (11/2 gc) to Rast tan (5 le)
Formation of aerial hyphae and Color thereof: Abundant, Cream (11/2 ca) to ashes (5 fe)
Soluble pigments: Produced (yellowish brown)
4) Starch-inorganic salt agar medium
Growth: Abundant
Color of substrate hyphae: Powder rose (6 ec) to redwood (6 le)
Formation of aerial hyphae and Color thereof: Abundant, light gray (c) to ashes (5 fe)
Soluble pigments: Produced (brown)
5) Tyrosine agar medium
Growth: Abundant
Color of substrate hyphae: Olive (11/2 ni) to coral rose (61/2 ic)
Formation of aerial hyphae and Color thereof: Abundant, White (a) to gray (e)
Soluble pigments: None
6) Nutrient agar medium
Growth: Moderate
Color of substrate hyphae: Light brown (4 ng) to oak brown (4 pi)
Formation of aerial hyphae and Color thereof: Little formed
Soluble pigments: None
7) Yeast-malt agar medium
Growth: Abundant
Color of substrate hyphae: Tile red (5 ne) to brick red (5 ng)
Formation of aerial hyphae and Color thereof: Abundant, White (a) to Silver gray (3 fe)
Soluble pigments: Produced (brown)
8) Oatmeal agar medium
Growth: Moderate
Color of substrate hyphae: Rast tan (5 le) to brick red (5 ng)
Formation of aerial hyphae and Color thereof: Abundant, Gray (g)
Soluble pigments: Produced (brown)
3. Physiological properties:
The temperature range for growth indicates the results of the strain after a 14-day cultivation period. Other items indicate the results after a 2 to 3 week-cultivation at 28° C.
1) Temperature range for growth: 5.5° to 46.5° C.
2) Liquefaction of gelatin: Not observed
3) Hydrolysis of starch: Not observed
4) Coagulation of skim milk powder and peptonization thereof: Not observed
5) Formation of melanoid pigment:
(i) Peptone-yeast extact-iron agar: Not observed
(ii) Tyrosine agar: Not observed
6) Utilization of carbon source (basic medium: Pridham Gottlieb-agar medium):
+ indicates that the strain utilizes the carbon source; and - indicates that the strain did not utilize the carbon source.
______________________________________ L-Arabinose: + D-Xylose: + D-Glucose: + Sucrose: - Raffinose: - D-Fructose: + L-Rhamnose: + Inositol: + D-Mannitol: +______________________________________
4. Chemotaxonomic properties:
Optical isomer of diaminopimelic acid in the strain: LL-form
Accordingly, the strain is classified into the genus Streptomyces of actinomycetes.
This strain was named Streptomyces sp. E-1625, and it was deposited at the National Institute of Bioscience and Human Technology of the Agency of Industrial Science and Technology under FERM BP-4965 as of Jan. 10, 1995 in terms of the Budapest Treaty.
The microorganism that produces Compound (I) of the present invention is cultivated by a method ordinarily used to cultivate actinomycetes. The medium for cultivating the microorganisms may be any of natural media and synthetic media, so long as it properly contains carbon sources, nitrogen sources, inorganic substances and the like that may be assimilated by the microorganisms.
Examples of the carbon sources include carbohydrates such as glucose, fructose, sucrose, stabilose, starch, dextrin, mannose, maltose and molasses; organic acids such as citric acid, maleic acid, acetic acid and fumaric acid; alcohols such as methanol and ethanol; hydrocarbons such as methane, ethane, propane and n-paraffins; amino acids such as glutamic acid; and glycerol.
Examples of the nitrogen sources include ammonium salts such as ammonium chloride, ammonium sulfate, ammonium nitrate and ammonium phosphate, amino acids such as aspartic acid, glutamine, cystine and alanine, urea, peptone, meat extract, yeast extract, dry yeast, corn steep liquor, soybean powder, cottonseed cakes, soybean casein, cazamino acid and Pharmamedia.
Examples of the inorganic substances include potassium monohydrogenphosphate, potassium dihydrogenphosphate, sodium dihydrogenphosphate, magnesium phosphate, magnesium sulfate, ferrous sulfate, manganese sulfate, copper sulfate, cobalt sulfate, zinc sulfate, nickel sulfate, calcium pantothenate, ammonium molybdate, potassium aluminum sulfate, barium carbonate, calcium carbonate, cobalt chloride and NaCl.
A substance that accelerates proliferation of strains or formation of Compound (I), such asvitamins, for example, thiamine, may be added to the medium as required. Further, a specific substance which is required for the microorganism is added to the medium.
The cultivation is carried out by shaking culture or aerial stirring culture at a temperature of from 20° to 40° C. while maintaining a nearly neutral pH range. Ordinarily, upon cultivation for from 3 to 7 days, Compound (I) is accumulated, reaching at the highest level, and the cultivation is completed.
Compound (I) accumulated in the culture is recovered from the culture by an ordinary method for recovering an Interleukin-1 production inhibiting compound from a culture.
That is, Compound (I) is isolated by extraction of a strain ingredient with a solvent such as acetone or methanol, removal of the strain by filtration or centrifugation, absorption or desorption treatment of an active substance through column chromatography or thin-layer chromatography using an adsorption resin, silica gel, cylanized silica gel, reverse-phase silica gel, aluminum, cellulose, diatomaceous earth, magnesium silicate, gel filter medium or ion-exchange resin, or partition with a suitable solvent.
During the above-mentioned purification step, Compound (I) is detected through silica-gel thin-layer chromatography and then through iodine color development or irradiation with an ultraviolet light of 253.6 nm.
The biological activities of Compound (I) will be described in the following Test Examples.
Test Example 1
Inhibiting Activity of the production of IL-1
With respect to Compound (I) of the present invention, the inhibiting activity of production of IL-1 β derived from THP-1 cells (ATCC No. TIB 202) of a human monocyte was examined. The amount of IL-1 β was determined by the ELISA method.
The THP-1 cells were suspended in an RPMI 1640 culture solution comprising 10% inactivated fetal bovine serum at a concentration of 1×10 5 cells/ml. The suspension was charged in a 24-well plate at a volume of 1 ml/well. PMA (phorbol 12-myristate 13-acetate, made by Wako Pure Chemical Industries, Ltd.; final concentration 30 nM) was added thereto, and the mixture was cultured in a mixed gas of 5% CO 2 and 95% air at 37° C. for 65 hours. The cells were differentiated in a macrophage form.
The cultivation plate was gently washed with a serum-free RPMI 1640 culture solution to remove the cells not adhered thereto, and the residue was cultured for 4 hours in a serum-free RPMI 1640 culture solution (1 ml/well) to which LPS (lipopolysaccharide, made by Difco Laboratories; a final concentration 25 μg/ml) and a compound to be tested were added simultaneously.
After the completion of the cultivation, the amount of IL-1 β which was released in the cultivated supernatant was determined using an IL-1 β determination kit (made by Amersham Corp.).
Percent inhibition of IL-1 production was calculated using the following equation to obtain IC 50 (50% inhibitory concentration).
Percent inhibition of IL-1 production (%) = (A-B)/(A-C)!×100
wherein:
A: amount of IL-1 produced when only LPS is added
B: amount of IL-1 produced when LPS and the compound to be tested are added
C: amount of IL-1 when LPS is not added
The results are shown in Table 1.
TABLE 1______________________________________Compound to be tested IC.sub.50 (M)______________________________________EI-1511-3 5.4EI-1511-5 3.6EI-1625-2 5.4______________________________________
As apparent from the results in Table 1, Compound (I) of the present invention have inhibiting activity of the production of IL-1.
Test Example 2
Antibacterial activity
A minimum growth inhibitory concentration (MIC) with respect to various bacteria is shown in Table 2.
TABLE 2______________________________________ MIC (μg/ml)Bacteria to be tested EI-1511-3 EI-1511-5 EI-1625-2______________________________________Staphylococcus aureus 20 20 10ATCC 6538PEnterococcus faecium 20 20 20ATCC 10541Bacillus subtilis 20 20 5No. 10707______________________________________
Antibacterial activity was determined by an agar dilution method using a medium (pH 7.0) comprising 3 g/l bactotrypton (made by Difco Laboratories), 3 g/l meat extract, 1 g/l yeast extract, 1 g/l glucose and 16 g/l agar.
The compound which is used as an IL-1 production inhibitor in the present invention can be administered as such or as a pharmaceutical composition either orally or parenterally. The form of the pharmaceutical composition is a tablet, pill, powder, granule, capsule, suppository, injection or eye drop.
The above-mentioned pharmaceutical composition can be formed by an ordinary method. It may contain various additives such as an excipient, lubricant, binder, disintegrator, suspending agent, isotonic agent, emulsifying agent, absorption accelerator and the like.
The carrier to be used in the pharmaceutical composition can include water, distilled water for injection, physiological saline, glucose, fructose, white sugar, mannitol, lactose, starch, corn starch, potato starch, cellulose, methyl cellulose, carboxymethyl cellulose, hydroxypropyl cellulose, arginic acid, talc, sodium citrate, calcium carbonate, calcium hydrogenphosphate, magnesium stearate, urea, silicone resin, sorbitan aliphatic, acid ester and/or glycerin aliphatic acid ester. These carries can be appropriately selected depending on the preparation from.
The dose of the interleukin-1 production inhibitor which is used for the above-mentioned purpose is determined depending on a desired therapeutic effect, administration method, administration period, and age and weight of patients. It is usually from 0.01 to 2 mg/kg a day for an adult in peroral or parenteral administration (for example, rectal administration by injection, drops or suppository, or application to the skin.)
The present invention will be illustrated specifically by referring to the following Examples and Preparation Examples.
EXAMPLE 1
Streptomyces sp. E-1511 (FERMBP-4729) was used as a seed strain. A medium (pH 7.0) comprising 10 g/l glucose, 10 g/l soluble starch, 3 g/l beef extract (made by Kyokuto Seiyaku Kogyo K.K.), 5 g/l powdery yeast extract S (made by Nippon Seiyaku K.K.), 5 g/l bactotryptone, 1 g/l potassium dihydrogenphosphate, 0.5 g/l magnesium sulfate 7-hydrate and 0.5 g/l magnesium phosphate 8 hydrate was used as a first medium.
One loopful of the strain was inoculated into 10 ml of the first medium filled in a 50-milliliter test tube. The strain was cultivated with shaking in each of two such tubes (total amount of the medium--20 ml) at 28° C. for 3 days.
Five milliliters of the first culture was inoculated into 50 ml of a second medium filled in a 300-milliliter Erlenmeyer flask. The culture was put into each of three such flasks (total amount of the medium--150 ml), and cultivated at 28° C. for 2 days with shaking (second cultivation). The second medium had the same formulation as that of the first medium.
Fifty milliliters of the obtained second culture was inoculated into 500 ml of a third medium filled in a 2-liter Erlenmeyer flask. The culture was cultivated in each of three such flasks (total amount of the medium--1.5 liters) at 28° C. for 2 days with shaking (third cultivation). The third medium had the same formulation as that of the second medium.
The obtained third culture (1.5 liters) was inoculated into 17 liters of a main fermentation medium filled in a 30-liter stainless steel jar fermenter. A medium (pH7.0) comprising 10 (v/v) % of Diaion HP-20 (made by Mitsubishi Chemical Corp.), 40 g/l soluble starch, 10 g/l soybean powder, 5 g/l corn steep liquor, 5 g/l dry yeast, 0.5 g/l potassium dihydrogenphosphate, 0.5 g/l magnesium phosphate 8 hydrate, 10 μg/l zinc sulfate 7 hydrate, 1 μg/l cobalt chloride 6 hydrate and 1 μg/l nickel sulfate was used as a main fermentation medium. The main fermentative cultivation was conducted at 28° C. for 6 days through aerial stirring (number of rotations--300 rpm, amount of gas: 18 L/min).
The obtained main fermentative culture (17 liters) was filtered through a 150 μm-mesh sieve to separate Diaion HP-20. Diaion HP-20 separated was placed on a Diaion HP-20 column (1 liter), washed with 6 liters of water, and eluted with a mixed solvent of methanol and acetone (7:3). The fraction containing EI-1511 was collected, concentrated to dryness under reduced pressure and dissolved in 2 liters of methanol. To 1 liter of the solution were added 10 g of ODS (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm). The mixture was then concentrated to dryness, put into a column filled with 400 ml of ODS (ODS-AQ-S50, made by YMC, 30 mm (diameter) ×500 mm), washed with a mixed solvent of 30% methanol and 0.1% acetic acid, and eluted with a mixed solvent of 80% methanol and 0.1% acetic acid. The fraction containing EI-1511 was collected, diluted to 1.5 times with water, passed through a column filled with 400 ml of ODS filled in a column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and then eluted with a mixed solvent of 65% acetone and 0.1% acetic acid.
The fraction containing EI-1511 was collected, diluted to 1.5 times with water, then passed through an ODS column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and eluted with a mixed solvent of 65% acetone and 0.1% acetic acid to separate the fraction containing EI-1511-3 and the fraction containing EI-1511-5.
The fraction containing EI-1511-3 was diluted to 1.5 times with water, then passed through an ODS column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and then eluted with a mixed solvent of 60% aceotone and 0.1% acetic acid. The fraction containing EI-1511-3 was collected, then diluted again to 1.5 times with water, passed through an ODS column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and eluted with a mixed solvent of 60% acetone and 0.1% acetic acid to obtain 90 mg of EI-1511-3.
The fraction containing EI-1511-5 was diluted to 1.5 times with water, passed through an ODS column (ODS-T, made by Nomura Kagaku K.K., 30 mm (diameter)×500 mm), adsorbed thereon, and eluted with a mixed solvent of 60% acetone and 0.1% acetic acid to collect the fraction containing EI-1511-5. The fraction containing EI-1511-5 was diluted again to 1.5 times with water, passed through an ODS column (ODS-T, made by Nomura Kagaku K.K., 30 mm (diameter)×500 mm), adsorbed thereon, and eluted with a mixed solvent of 60% acetone and 0.1% acetic acid to obtain 15 mg of EI-1511-5.
During the above-mentioned procedure, the compounds EI-1511-3 and 1511-5 were detected through silica gel thin-layer chromatography and then iodine color development or irradiation with an ultraviolet light of 253.6 nm.
EXAMPLE 2
Streptomyces sp. E-1625 (FERM BP-4965) was used as a strain. A medium (pH 7.0) containing 10 g/l glucose, 10 g/l soluble starch, 3 g/l beef extract (made by Kyokuto Seiyaku Kogyo K.K.), 5 g/l powdery yeast extract S (made by Nippon Seiyaku K.K.), 5 g/l bactotryptone, 1 g/l potassium dihydrogenphosphate, 0.5 g/l magnesium sulfate 7 hydrate and 0.5 g/l magnesium phosphate 8 hydrate was used as a first medium.
One loopful of the strain was inoculated into 10 ml of the first medium filled in a 50-milliliter test tube. The strain was cultivated with shaking in each of two such test tubes (total amount of the medium--20 ml) at 28° C. for 2 days.
Five milliliters of the first culture were inoculated into 50 ml of a second medium filled in a 300-milliliter Erlenmeyer flask. The culture was put into each of four such flasks (total amount of the medium--200 ml), and cultivated at 28° C. for 2 days with shaking (second cultivation). The second medium had the same formulation as that of the first medium.
Five milliliters of the obtained second culture was inoculated into 50 ml of a main fermentation medium filled in a 300-milliliter Erlenmeyer flask. The culture was put into each of forty such flasks (total amount of the medium--2 liters) with shaking at 28° C. for 6 days (main fermentative cultivation). A medium (pH 7.0) containing 10 (v/v) % of Diaion HP-20 (made by Mitsubishi Chemical Corp.), 40 g/l soluble starch, 10 g/l soybean powder, 5 g/l corn steep liquor, 5 g/l dry yeast, 5 g/l potassium dihydrogenphosphate, 0.5 g/l magnesium phosphate 8 hydrate, 10 μg/l zinc sulfate 7 hydrate, 1 μg/l cobalt chloride 6 hydrate and 1 μg/l nickel sulfate was used as a main fermentation medium.
Two liters of the obtained main fermentation culture was centrifuged to separate the cells. To the cells was added 2 liters of methanol, and the mixture was stirred and then filtered. The filtrate was diluted to 5 times with water, then passed through a Diaion HP-20 column (400 ml), absorbed thereon, washed with 1.6 liters of 20% methanol, and eluted with a mixed solvent of methanol and acetone (7:3).
The fraction containing EI-1625-2 was collected, and concentrated under reduced pressure to remove acetone. Water was added to the residue to form a 20% methanol solution. The solution was passed in two divided portions through a Diaion HP-20SS column (made by Mitsubishi Chemical Corp.), adsorbed thereon, and then eluted with a mixed solvent of 0.1% acetic acid and methanol at a linear concentration gradient of from 20 to 100%.
The fractions containing EI-1625-2 were combined and diluted to 2 times with water. The thus-obtained solution was passed in two divided portions through an ODS column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and then eluted with a solution of 75% methanol and 0.1% acetic acid.
The fractions containing EI-1625-2 were collected, concentrated to dryness under reduced pressure, dissolved in 5 ml of 75% methanol, passes through an ODS column (ODS-AQ-S50, made by YMC, 30 mm (diameter)×500 mm), adsorbed thereon, and eluted with a solution of 75% methanol and 0.1% acetic acid to obtain 20 mg of EI-1625-2.
During the above-mentioned procedure, EI-1625-2 was detected through silica gel thin-layer chromatography and then through iodine color development or irradiation with an ultraviolet light of 253.6 nm.
Preparation Example 1: Tablet
______________________________________EI-1511-3 100 gLactose 40 gCorn starch 18 gCarboxymethyl cellulose calcium 10 g______________________________________
The mixture having the above-mentioned formulation was kneaded with 42 ml of a 10% hydroxypropyl cellulose solution. The thus-obtained mixture was pulverized by means of a pushing pulverizer fitted with a 1-millimeter basket. The resulting powder was formed into granules with the addition of magnesium stearate, and a tablet (170 mg) containing 100 mg of EI-1511-3 and having a diameter of 8 mm was prepared in a usual manner.
Preparation Example 2: Tablet
______________________________________EI-1511-5 100 gLactose 40 gCorn starch 18 gCarboxymethyl cellulose calcium 10 g______________________________________
Using the mixture having the above-mentioned formulation, a tablet (170 mg) containing 100 mg of EI-1511-5 and having a diameter of 8 mm was prepared in the same manner as in Preparation Example 1.
Preparation Example 3.: Tablet
______________________________________EI-1625-2 100 gLactose 40 gCorn starch 18 gCarboxymethyl cellulose calcium 10 g______________________________________
Using the mixture having the above-mentioned formulation, a tablet (170 mg) containing 100 mg of EI-1625-2 and having a diameter of 8 mm was prepared in the same manner as in Preparation Example 1.
Preparation Example 4: Capsule
______________________________________ EI-1511-3 50 g Lactose 80 g Potato starch 38 g______________________________________
The mixture having the above-mentioned formulation was kneaded with 42 ml of a 10% hydroxypropyl cellulose solution. The thus-obtained mixture was pulverized in the same manner as in Preparation Example 1, and magnesium stearate was added to the powder. A capsule (170 mg) containing 50 mg of EI-1511-3 was prepared in a usual manner.
Preparation Example 5: Capsule
______________________________________ EI-1511-5 50 g Lactose 80 g Potato starch 38 g______________________________________
Using the mixture having he above-mentioned formulation, a capsule (170 mg) containing 50 mg of EI-1511-5 was prepared in the same manner as in Preparation Example 4.
Preparation Example 6: Capsule
______________________________________ EI-1625-2 50 g Lactose 80 g Potato starch 38 g______________________________________
Using the mixture having the above-mentioned formulation, a capsule (170 mg) containing 50 mg of EI-1625-2 was prepared in the same manner as in preparation Example 4.
Preparation Example 7: Soft capsule
Ten grams of EI-1511-3 was dissolved in 100 g of soybean oil, and the obtained solution was poured into a capsule in a usual manner to prepare a soft capsule containing 10 mg of EI-1511-3.
Preparation Example 8: Soft capsule
Ten grams of EI-1511-5 was dissolved in 100 g of soybean oil, and the obtained solution was poured into a capsule in a usual manner to prepare a soft capsule containing 10 mg of EI-1511-5.
Preparation Example 9: Soft capsule
Ten grams of EI-1625-2 was dissolved in 100 g of soybean oil, and the obtained solution was poured into a capsule in a usual manner to prepare a soft capsule containing 10 mg of EI-1625-2.
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Provided is an Interleukin-1 production inhibiting compound represented by formula (I) ##STR1## wherein R denotes 4-methyl-1-pentenyl, 5-methyl-1,3-heptadienyl or 1-methylpentanyl.
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BACKGROUND OF THE INVENTION
The invention relates to a cooking grill, particularly for grilling steaks, with a passage the vertically extending inlet section of which is disposed between two driven and heated parallel inlet rolls rotating at the same peripheral speed and conveying the food item downwards, the passage having a slightly inclined second section which extends between one of the inlet rolls and a third heated roll which latter is parallel to the inlet rolls and is driven to rotate counter to the direction of rotation of the one inlet roll and at the same peripheral speed.
In a grill which is disclosed in the German Utility Model No. 81 19 752, the width of the passage is chosen in such a way that a steak can travel through the passage at a slight contact pressure.
OBJECTS AND SUMMARY OF THE INVENTION
An object of the invention is to improve a grill of the type described above in such a manner that steaks of different sizes and/or thicknesses can travel through the passage with ease and are subjected to an optimal contact pressure.
The invention is characterized in that the one inlet roll which defines with the third roll the second section of the passage is mounted for movement in a direction at right angles to the axes of the rolls so as to simultaneously adjust the width of both sections of the passage.
Although one side of each food item to be grilled contacts two rolls one after another, whereas the other side of the item contacts a single roll, it is sufficient to adjust only that inlet roll which defines in part both sections of the passage in order to widen or narrow both sections of such passage. This contributes to simplicity of the adjustable grill.
The rolls are shielded in order to avoid accidents. This is achieved by the provision of a cover which defines an inlet opening above the inlet section of the passage. The width of the inlet opening is adjustable in synchronism and proportionally with adjustment of the width of the passage.
In order to clearly draw the operator's attention to the particular adjustment of the passage and to thus prevent the introduction of too large or too thin steaks not in conformity with the selected adjustment of the passage, there is preferably provided a device for adjusting the width of the passage as well as a device for adjusting the width of the inlet opening. The two adjusting devices are coupled to each other. Thus, the operator is able to ascertain the readily recognizable selected width of the opening, and in case it does not correspond with the thickness of the steak to be introduced for grilling, the operator will be able to adjust the width of the opening and with this also the width of the passage.
It is a further object of the invention to increase the speed of the steaks and, to this end, there is provided a microwave radiator the radiation of which is directed into the passage. The microwaves effect an additional heating of the steaks so that the total travelling time can be shortened. In contrast to the heating of the rolls, the microwaves also have a direct effect on the inner steak parts. By means of a corresponding dosage of the microwave influence, it is possible to grill the inner parts of the steaks to a desired extent at a constant speed of the steaks and unchanged heating of the rolls. Futhermore, and in contrast to the heating of the rolls, the intensity of the microwaves can be adjusted very quickly so that, with steaks travelling one after another, one can be finished intensively in its inner part, and another one which follows less intensively by adjusting the microwave radiation correspondingly. The intensity of the microwaves can also be adjusted very quickly to conform to the selected width of the passage and thereby to the thickness of the steaks travelling therethrough. This adjustment is preferably carried out automatically in dependency on the adjustment of the width of the passage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a horizontal sectional view of a grill which embodies one form of the invention;
FIG. 2 is a side elevational view of the grill as seen in the direction of arrow II in FIG. 1, with certain parts omitted and with a portion of the housing broken away;
FIG. 3 is a fragmentary side elevational view as seen in the direction of arrow III is FIG. 1, with the housing and numerous other parts omitted;
FIG. 4 is a fragmentary sectional view as seen in the direction of arrows from the line IV--IV of FIG. 1; and
FIG. 5 is a diagrammatic view of a control unit which regulates the heating action in dependency on the selected width of the passage and the inlet opening.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1-3 show three heatable rolls 1, 2, 3 which are movably mounted in a housing 10 for rotation about horizontal axes, and their ends are respectively provided with stub shafts 4, 7; 5, 8 and 6, 9. The rolls 1 and 2, the so-called inlet rolls, define between themselves the vertical inlet section 11 of an essentially vertical passage 12. The rolls 1 and 3 define a further section 13 of the passage 12 and the section 13 is slightly inclined with reference to the vertical. The rolls 1, 2, 3 are driven by an endless chain 17 by means of attached sprocket wheels 14 to 16, the chain being driven in the direction of the arrow 20 by means of the driving sprocket wheel 18 of a motor 19. The chain 17 is tensioned by a chain fixture 21 which is equipped with a spring-biased tensioning wheel 23. The spring is shown at 22. The sprocket wheel 15 of the roll 2 engages the outer surface of the chain 17 while the sprocket wheels 14 and 16 of the two other rolls 1 and 3 engage the inner surface of the chain so that the rolls are driven in the directions of the arrows shown in FIG. 3 and determine the direction of advancement of items in the passsage 12. The peripheral speed of all rolls is the same because the rolls have identical diameters, the same as the pinions 14, 15, 16.
The narrowest portions of the inlet section 11 and second section 13 of the passage 12 have the same width. These sections can be widened simultaneously by adjusting the position of the roll 2. The gap 24 between the fixed rolls 1 and 3 is narrower than the minimum possible width of the passage 12.
While the bearings 30, 32 and 36, 37 for the rolls 3 and 1 are fixedly mounted in stationary bearing frames 34, 35 of the housing 10, the bearings 31 for the roll 2 are installed in one end each of pivotable arcuate bearing frames 38, 39. The other ends of the two arcuate bearing frames are installed in tumbler bearings 40, 41 which are mounted in the bearing frames 34, 35 for movement about an axis parallel to the axes of the rolls. When the bearing frames 38, 39 are moved in the direction of the arrow 42, the width of the inlet section 11 as well as of the second section 13 increases. When the bearing frames 38, 39 are moved in the opposite direction, the width of the sections 11 and 13 decreases. Several different positions of the roll 2 are indicated in FIG. 2 by phantom lines. The pivoting end of the bearing frame 39 is connected to a lever 43 which is connected to another lever 44, the latter being fastened to a shaft 45. The shaft 45 is parallel to the rolls 1 to 3 and is rotatably mounted in the bearing frames 34, 35. The bearing frame 38 is connected with levers which are mirror symmetrical to the levers 43, 44 and are fastened to the other end of the shaft 45. Accordingly, the shaft 45 rotates when the bearing frame 39 moves and causes the bearing frame 38 to perform an identical angular movement.
The adjusting device 48 including the bearing frame 39, the levers 43, 44 and the parts connected to the other end of the shaft 45 operates as a parallel motion for the roll 2 which thus remains parallel to the other rolls 1 and 3 in each of its positions.
A handle 49 which is accessible from the exterior of the housing 10 serves the purpose of operating and adjusting device 48. This handle can rotate a feed screw 50 which meshes with a nut 51. The nut 51 is non-rotatably attached to the lever 44 so that, when the handle 49 is rotated, the bearing frame 39 is pulled in the direction of arrow 42 or pushed in the opposite direction.
A wall of the housing 10 serves as a cover for the upward extension of the inlet section 11 and has an inlet opening 56 which extends along the full axial length of the rolls 1, 2 and 3. The character 57 designates a gate (see also FIG. 4) which is rotatable around an axis parallel to the rolls and by means of which the width of the inlet opening 56 can be adjusted as indicated by the double-arrow 60. The adjustment is always made in such a way that the width of the inlet opening 56 approximates the width of the passage 12. For this purpose, the gate 57 is attached by a coupling rod 61 to a strap 84 which is clamped to the shaft 45. This guarantees that, by actuating the adjusting device 48 to adjust the width of the passage 12, the gate 57 is adjusted at the same time within the range indicated by the arrow 58 to change the width of the inlet opening 56 so that this opening admits only steaks having a width such that the steaks can be treated with optimal contact pressure in the passage 12.
The rolls 1, 2, 3 are electrically heated by a heating devices which are mounted in the rolls, and the electrical conductors of the heating devices extend through the stub shafts 7, 8, 9 each of which constitutes a tube.
The character 65 designates in FIG. 1 a thermo sensor which contacts the peripheral surface of the roll 3 and monitors the surface temperature of this roll. The character 66 designates a width sensor which, in response to adjustment of the handle 49, indicates as measured value the selected width of the passage 12. A signal denoting such measured value is transmitted to a central control unit 68 (see FIG. 5) by way of a conductor 67. The signal from the thermo sensor 65 reaches the control unit 68 through a conductor 69. Depending upon the intensity of signals transmitted by the conductors 67 and 69, according to a preselected program, and depending upon the adjustment of the knobs 70 and 71, the heating of rolls 1, 2, 3 is controlled by the control unit 68 via conductors 72, 73, 74, and the drive motor 19 is controlled via conductor 75.
The grill is operated in the following manner: At first, the rolls, 1, 2, 3 are pre-heated. The condition of readiness of the device for operation which is indicated by the indicator 76 of the control unit 68. Now the steaks can be introduced from the top through the inlet opening 56, and the size of the steaks depends on the particular adjustment of the width of the passage 12 and of the inlet opening 56. The steaks descend in and through the passage 12 in the direction of the arrow 77 and are grilled before they reach the outlet opening 78 of the housing 10 completely finished. If bigger, thicker, smaller or thinner steaks are to be grilled, the width of the inlet opening 56 and the width of the passage 12 are adjusted accordingly by manipulating the handle 49.
As a modification of or in addition to the aforedescribed embodiment, a microwave radiator 80 (shown by dotted lines in FIG. 2) is provided to direct radiation between the rolls 1 and 3 into the center of the passage 12 so that the radiation is distributed along the entire length of the rolls. The intensity of radiation which is emitted by the microwave radiator 80 can be adjusted by the control unit 68 via control conductor 81 depending upon the selected width of the passage 12 such as is signaled to the control unit 68 via conductor 69.
Instead of the microwave radiator 80 or in addition thereto, a microwave radiator 82 can be provided as shown by dotted lines in FIGS. 1 and 2. This radiator is installed in the axial extension of the center of and adjacent to the passage 12, and the radiation which issues therefrom is directed into the center of the passage in parallelism with the rolls, i.e., at right angles to the plane of FIG. 2. In this case, too, the intensity of the radiation can be adjusted by the control unit through a conductor corresponding to the control conductor 81. A further microwave radiator 83 can be mounted on the strap 84.
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Steaks are grilled, one after the other, while advancing through a passage which is defined by three heated parallel rolls. A first roll is disposed at one side and the other two rolls are installed at the opposite side of the passage. The rolls are driven to advance the steaks downwardly into and through the passage. One of the other two rolls is adjustable at right angles to its axis so that the width of the entire passage can be adjusted.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multi-stage system for treating hazardous wastes such as oil well drilling waste material, wherein a high efficiency multi-stage incinerator includes a rotary kiln stage fired by a venturi shrouded burner having controlled inflow of burner fuel and air flow, with an upstanding generally vertical scrubbers that is fired at its lower end by one or more secondary burners, and with vertically spaced water sprayers and cone shaped annular baffles treating the gases produced from combustion with a high surface area of dispersed water droplets.
2. General Background
Rotary kilns and incinerators have been commercially available and used in the treatment of various types of waste including municipal waste, industrial waste, and hazardous waste. Hazardous waste is often contained in open pits or pools. These pits can contain oil, oil drilling wastes, and complex mixtures of hazardous material such as refining refuse and/or plural refinery chemical discharges.
In order to "treat" these open pit hazardous waste products, simple burning has been used in the past. Open pit burning is a highly inefficient and undesirable method of disposing of hazardous waste in pits because of the fact that incomplete combustion scatters soot over a large area, polluting the surrounding area. The settling soot creates a further pollution problem for ground water.
In order to completely decompose hazardous waste, municipal waste, and industrial waste, a high temperature, highly efficient combustion can be utilized. The gaseous discharge of this combustion can be scrubbed so that the gaseous output does not contain polluted or hazardous particulate material or gaseous material which might be an additional source of pollution even after combustion of the initial hazardous waste product. A problem often encountered with the treatment of hazardous waste is that it must be able to handle high product loading rates. Open pits can contain thousands of barrels of waste material that must be incinerated quickly.
Various patents have issued relating to various rotary kiln constructions. Indeed, rotary kilns per se are commercially available. An example of a rotary kiln can be seen in the recently issued U.S. Pat. No. 4,730,564 entitled "Multi-Staged Kiln" issued to Harry Abboud. The Abboud patent discloses a multi-stage rotary kiln for burning waste, suitably skid mounted for easier transport. The kiln includes a pair of concentric tubes affixed one inside the other and rotatable, a first large diameter tube and a second tube of small diameter provided at one end with circumferential wall openings mounted inside the first large diameter tube. An annular passageway between the two tubes is provided and an opening through the second small diameter tube provides a continuous flow path for introducing waste and the hot burning gases. The hot gases flowing concurrently with the waste via the annular passageway and the circumferential openings into and through the second tube. The feed mechanism introduces waste into the annular passageway and an elevator lifts the burning waste from the annular passageway and passes the same into the circumferential openings and the burning waste is transported through the smaller tube and discharged.
Other patents that relate generally to the incineration of waste material using rotary kiln can be seen in the Angelo U.S. Pat. No. 4,734,166 entitled "Furnace For the Selective Incineration Or Carbonization Of Waste Materials"; the Reed et al., U.S. Pat. No. 4,724,777 entitled "Apparatus For Combustion of Diverse Materials And Heat Utilization"; the Bolle U.S. Pat. No. 3,882,801 entitled "Incinerator For Domestic And Industrial Solid, Semi-Liquid Or Liquid Waste"; and the Jaronko U.S. Pat. Nos. 3,906,874 and 3,938,450 entitled "Mobile Furnace Vehicle".
The concept of using a scrubber to treat the gaseous discharge of incineration is disclosed generally in several patents including for example the Marchand U.S. Pat. No. 4,704,972 entitled "Method And Apparatus For Reducing Acid Pollutants In Smoke"; Warner U.S. Pat. No. 4,557,202 entitled "Exhaust Gas Treatment Method And Apparatus"; the Caffyn et al U.S. Pat. No. 4,424,755, entitled "Incineration System Having Cyclonic Oxidation Chamber"; the Celis U.S. Pat. No. 4,392,875 entitled "Smog Eliminator"; the YaGuchi et al U.S. Pat. No. 4,269,806 entitled "Scrubber For Removal of Sulphur Dioxide From Exhaust Gas"; the Spitz U.S. Pat. No. 4,162,654 entitled "Pollution Control Incineration System", the Hartman U.S. Pat. No. 4,168,958 entitled "Smokestack Air Washer", the Morales U.S. Pat. No. 4,149,901 entitled "Pollution Control And Convection Heater", the Menigat et al U.S. Pat. No. 3,921,543 entitled "Method Of Incinerating Salt Containing Liquid Sludge", the Crawley U.S. Pat. No. 3,823,531 entitled "Gas Cleaner", the Torrence U.S. Pat. No. 3,762,858 entitled "High Temperature Scrap Cleaning Conveyor", the Smuck U.S. Pat. No. 3,701,237 entitled "Smoke Eluminator", the Snelling U.S. Pat. No. 3,646,897 entitled "Method and Apparatus for Pollution Free Burning of Automobile Bodies"; the McClure U.S. Pat. No. 3,533,608 entitled "Smog Arrester", the Bowman U.S. Pat. No. 3,530,806 entitled "Incinerator", the Tomany et al U.S. Pat. No. 3,520,649 entitled "System of Removal of Sulphur Oxide and Fly Ash From Power Plant Flue Gases", the Ford U.S. Pat. No. 3,395,656 entitled "Fly Ash Removal Device For Incinerators", the Frankland U.S. Pat. No. 2,978,998 entitled "Incinerator", the Otto U.S. Pat. No. 2,771,281 entitled "Benzol Scrubbing Method and Apparatus"; the Kameya U.S. Pat. No. 2,709,580 entitled "Smoke Washer"; and the Durant U.S. Pat. No. 999,213 entitled "Apparatus For Bringing a Gas Into Contact With A Liquid".
In the Kameya '580 patent there is disclosed a smokestack of preferably cylindrical shape having dished, annular plates disposed one above the other supported by struts. A hollow spray head of substantially hemispherical shape is mounted on the upper convex side of one of the plates and centrally of the plate with a plurality of spray nozzles projecting radially from the spray head at equal angular intervals therein and are directed toward the outer edge of one of the plates for directing sprays of water over the outer edges of the plates and causing the water to flow downwardly over the outer edges of a successfully lower plates and over the outer edge of the bottom into the bottom annular trough.
Applicant herein is the named inventor of a prior U.S. Pat. No. 3,807,932 directed to a burner construction that incorporates a burning head mounted within a venturi shape shroud. Atomizing is accomplished using fluid that is mixed with the burner fuel.
The present invention provides an improvement over these prior art patents by disclosing a new, improved combination that includes the use of first and second burners positioned respectively at the intake of the rotary kiln and at the bottom of the scrubber portion adjacent the discharge from the rotary kiln. Each of the burners is preferably of an atomizing type, having a burning head mounted internally of a venturi shaped shroud, the burner receiving controlled flow of both air and liquid fuel such as low cost diesel fuel so that the flow of fuel for burning and the flow of air through the venturi can be controlled at both the primary and at the secondary burners to produce a highly efficient burn. Particulate matter leaving the bottom end portion of the scrubber stack is cleansed of any minute or particulate material that might not be completely burned during combustion.
SUMMARY OF THE PRESENT INVENTION
The present invention thus provides an improved hazardous waste disposal system that includes a rotary kiln and a burner for transferring intense heat to the interior of the kiln. A material feed is provided for adding hazardous material to the kiln on a batch or continuous basis and a generally upstanding, vertical scrubber stack is provided for receiving gaseous solid material discharge from the kiln.
A plurality of vertically stacked spray heads are positioned within the scrubber stack together with a plurality of concentric annular vertically stacked cones disposed within the stack and respectively with each of the spray heads.
The spray heads are positioned to spray fluid onto the plurality of cones so that the water cascades from one cone to the next and the flow of gaseous material discharged from the kiln proceeds generally upwardly in the scrubber stack at least some of the gaseous material flowing between the cones.
In the preferred embodiment, the primary and secondary burners are each atomizing type burners, which mix air and fuel in an atomizing fashion, each burner being preferably surrounded with a venturi shaped shroud to enhance air flow to the flame.
In the preferred embodiment, the material feed can include a hydraulic ram for forcing heavy hazardous material into the kiln.
In the preferred embodiment, the secondary burner is positioned at the lower end portion of the scrubber stack, below the spray heads.
BRIEF DESCRIPTION OF THE DRAWINGS
For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like parts are given like reference numerals, and wherein:
FIG. 1 is a sectional elevation view of the preferred embodiment of the apparatus of the present invention;
FIG. 2 is a side, partial elevational view of the preferred embodiment of the apparatus of the present invention;
FIGS. 3, 3A and 3B are a partial cutaway view of the preferred embodiment of the apparatus of the present invention;
FIG. 4 is a fragmentary view of the preferred embodiment of the apparatus of the present invention;
FIG. 5 is a fragmentary elevational view of the preferred embodiment of the apparatus of the present invention illustrating the scrubber stack portion thereof;
FIG. 6 is a sectional elevational fragmentary view of the preferred embodiment of the apparatus of the present invention;
FIG. 7 is a fragmentary view of the preferred embodiment of the apparatus of the present invention illustrating the demisters;
FIG. 8 is a fragmentary side sectional view of the preferred embodiment of the apparatus of the present invention illustrating the demisters;
FIG. 9 is a fragmentary cutaway view of the preferred embodiment of the apparatus of the present invention illustrating the cyclone vane portion thereof;
FIG. 10 is a fragmentary perspective view of the preferred embodiment of the apparatus of the present invention illustrating one of the scrubber cones; and
FIG. 11 is a schematic view of the preferred embodiment of the apparatus of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1 and 2 illustrate generally the preferred embodiment of the apparatus of the present invention designated generally by the numeral 10. In FIGURE 1, there can be seen a sled or skid 12 of structural steel, for example, that supports rotary kiln 13 thereon. Rotary kiln 13 is basically a commerically available, generally cylindrical rotary kiln having an external gear 14 mounted circumferentially about the outer wall 15 of the kiln 13 and driven by variable speed motor 16 preferably powering gear drive 17 which intermeshes with gear 14. Kiln 13 provides an intake 18 end portion and a discharge 19 end portion. The axis of rotation of the kiln is inclined so that the intake 18 is higher than the discharge 19. In this manner of operation, the kiln 13 will gradually convey waste material to be burned from the intake 18 to the discharge 19.
Burner 22 transfers intense heat to kiln 13 interior, and is preferably an atomizing type burner having a burner head 23 which receives air flow via line 24 and fuel such as diesel oil or the like via line 25 and atomizes that mixture at nozzle 21 to produce a burn. The burner head 23 (FIGS. 3 and 6), is mounted within a generally annular venturi shaped shroud 26. A pair of longitudinally extending perforated air lines 27 convey air from line 24 to and along the full length of kiln 13. The air lines can direct air in opposite directions by alternating placement of the perforations. Air can also be routed to circumferential perforated rings 27A, 27B to elbows 27C, as shown in FIG. 3B, so that air can be added to the burn immediately downstream of shroud 26. The construction and operation of burner 22 can be seen for example in U.S. Pat. No. 3,807,932 issued to Applicant herein Jack Dewald, and incorporated herein by reference.
Hydraulic ram 28 receives bulk material via hopper 29 such as heavy solid hazardous waste material to be burned. Alternatively, material can be supplied via a flow line (not shown) and pumped into the intake 18 of kiln.
Vertical tower 30 as can best be seen in FIGS. 1-2 and 5-6 includes secondary burner chamber 35 and scrubber 40. Blower 50 forces air into secondary burner or afterburner chamber 35 via left and right ducts 51 and into the lower end portion 41 of scrubber 40 at left and right inlets 52. Scrubber 40 is an elongated generally upstanding vertical structure having lower 41 and upper 42 end portions with a hollow interior 43 that communicates with secondary burner chamber 35. One or more secondary burners 36 communicate with secondary burner chamber 35. Each secondary burner 36 is preferably a venturi shaped burner that atomizes fuel such as diesel oil during use. Secondary burners 36 are thus similar in construction and operation to burner 22, as shown in FIGS. 3B and 4.
Disposed within the interior 43 of scrubber stack 40 are a plurality of liquid spray manifold assemblies 60, 62, 64, 66, each being connected to influent flow line 61 for conveying water as illustrated by the arrows 67 to the scrubber 43 interior. Each spray manifold assembly 60, 62, 64, 66 is fitted with a plurality of adjustable liquid nozzles (13 preferred) positioned to spray water against the outer walls to totally saturate the exhaust gases. Water that splashes off the scrubber walls, and condenses on the upper cones and demister vanes fall upon a plurality of cones or conically shaped baffles 70-72 (FIGS. 6-10) including a first upper plurality 70, a second middle plurality 71, and a third lowermost plurality 72. Each plurality of baffles 70-72 includes cones of gradually increasing diameter beginning with a smaller diameter uppermost cone and ending with a lower larger diameter cone, and cascade off the cones into reservoirs 68 and 69.
Spray manifolds 62 and 64 are positioned generally above the plurality of baffles 71, as shown in FIG. 6. The spray manifolds 60, 62, 64, 66 are positioned to spray water against the outer scrubber walls and bounce back upon the surface of each of the plurality of baffles 70-72 allowing water to cascade downwardly so that some of the air flow upwardly within the interior 43 of scrubber 40 proceeds between cone members and is scrubbed of particulate matter by the cascading water. Reservoirs 68, 69 catch water that is discharged from baffles cones 70-72 for collection by effluent flow lines 65.
As air is forced into secondary chamber 35, it rises upwardly within the interior 43 of scrubber 40. A pair of spaced apart, static cyclone vanes 80, 82 are positioned vertically apart within scrubber 40 interior 43. Vanes 80, 82 are shown more particularly in FIG. 9, each cyclone vane including a plurality of inclined, radial vanes 83 attached to a central hub 84 and supported at their periphery by an annular, cylindrical outer wall 85. The cyclone vanes 80, 82 impart a rotational flow to air rising upwardly within the interior 43 of scrubber 40.
Demister 90 includes a plurality of elongated members 91, each being generally V shaped in cross section, having flanges 92, 93 which are approximately 90° with respect to one another, forming an underside 94 that is in the form of an inverted V. Arrows 95 indicate the flow of gaseous material between the members 91 in FIGS. 7 and 8. Mist and moisture contained within the air exiting the top section 42 of scrubber 40 collects upon the undersurface 94 and drips downwardly so that minimal liquid material exits the scrubber 40.
In FIG. 11, a flow chart illustrates the recirculation of solid material which is contained in the effluent flow stream 65, as well as the injection of fuel to the primary burner 22 and the secondary burners 35. Settling basin 100, provides a plurality of separate sections 101-104 defined by a plurality of transverse baffles 105. Each section 101-104 is "cleaner" than the previous, as solids gradually settle out. Settleable solids can be incinerated at burner 22 and kiln 13. Pump 106 transfers water via line 61 back to scrubber 40. A pair of air compressors 110, 112 supply air via line 27 to burner 22 and via line 114 to secondary burners 36 which interface with secondary or after burner section 35. Burner 22 and after burners 36 are supplied with fuel via lines 25 and 25A respectively. Chemical treatment tank 115 can be used to add water treatment chemicals to settling tank 100. Solid ash disposal from kiln 13 and afterburner 35 is via line 116 to ash disposal tank 117
The above-described apparatus has been successfully tested with regard to emissions data. The following are emissions data collected from the Portable Rotary Kiln Combustion System during testing. Particulate concentration data, grain/DSCF, have been corrected to 7% oxygen. All other data, including particulate emission rate data, 1b/hr, are reported without the oxygen correction.
Also presented are results of metals analysis on the slurry water, incinerator ash, and waste oil samples collected during the compliance tests.
__________________________________________________________________________CYCLONE RECYCLE CORPORATIONPORTABLE ROTARY KILN COMBUSTION SYSTEM DEQ VARIANCEPARAMETER RUN 1 RUN 2 RUN 3 AVG. LIMITS__________________________________________________________________________DATE 2-1-90 2-1-90 2-2-90TIME 1839-2029 2211-2357 154-339PARTICULATE - *(grain/DSCF) 0.05517 0.01997 0.03589 0.03701 --(lb/hr) 2.504 0.934 1.629 1.689 4.60SULFUR DIOXIDE 2.222 3.729 3.105 3.109 6.74(lb/hr)OXIDES OF NITROGEN 2.910 3.080 2.967 2.986 8.875(lb/hr)CARBON MONOXIDE 0.283 0.190 0.115 0.196 2.67(lb/hr)TOTAL HYDROCARBONS 2.104 1.670 1.017 1.597 3.59(lb/hr)OXYGEN 11.25 11.28 11.06 11.20 --(test monitor, %)STACK GAS DATATEMPERATURE, F. 175 174 180 176MOISTURE, % 32.99 33.15 35.71 33.95VELOCITY, ft/sec 4.51 4.67 4.56 4.58VOLUMETRIC FLOW,ACFM 13815.8 14303.2 13962.1 14027.0DSCFM 7724.5 7984.5 7436.1 7715.0__________________________________________________________________________ * Percent of isokinetic sampling during particulate emission determination is; Run 1 93.88%, Run 2 101.81%, Run 3 107.51%.
__________________________________________________________________________CYCLONE RECYCLE CORPORATIONPORTABLE ROTARY KILN COMBUSTION SYSTEMMETALS ANALYSIS DNR 29-B FEED INCINERATOR WASTE/SOIL MATERIAL SLURRY WATER - (mg/l) ASH MIXTUREMETAL (mg/kg) Run 1 Run 2 Run 3 (mg/kg) LIMIT__________________________________________________________________________Arsenic 9.1 0.021 0.022 0.026 12 10Barium 475 106 118 126 910 2000Cadmium 0.85 0.028 0.047 0.016 0.82 10Chromium 5.6 0.08 0.09 0.08 25 500Lead 90.5 0.37 0.33 0.40 81 500Mercury 0.475 0.0078 0.0087 0.0075 6.26 10Selenium ND ND ND ND ND 10Silver 0.075 0.015 ND ND 0.84 200Zinc 93.35 0.325 0.325 0.418 138.8 500Carbon content 5.36 -- -- -- 0.14(wt %)weight loss at 550 deg C.pH Units 6.6 6.7 6.8__________________________________________________________________________ ND ` None detected
PROCEDURE
Emissions were determined using EPA Methods found in Appendix A, Part 60, Title 40 of the Code of Federal Regulations. A brief description of each method used follows.
METHOD 1: SAMPLE AND VELOCITY TRAVERSES FOR STATIONARY SOURCES
The Portable Rotary Kiln Combustion System has a stack diameter of 96.75 in. Samples and measurements were collected at a point 0.51 stack diameters upstream and 6.68 stack diameters downstream. Under these conditions the method requires 24 traverse points. The stack crosssection at the sampling point was divided into 24 equal areas with the sampling point located at the centroid of each area.
METHOD 2: DETERMINATION OF STACK GAS VELOCITY AND VOLUMETRIC FLOW RATE (TYPE S PITOT TUBE)
The average gas velocity in the stack was determined from the gas molecular weight, moisture content and the measurement of the average velocity head with a type "S" pitot tube. Dry volumetric flow rate was determined from the velocity and stack diameter.
METHOD 3: GAS ANALYSIS FOR CARBON DIOXIDE, OXYGEN, EXCESS AIR, AND DRY MOLECULAR WEIGHT
The dry molecular weight of the stack gas was determined using an Orsat analyzer. The Orsat measures the concentration of oxygen, carbon monoxide and carbon dioxide. The remaining gas components are assumed to be nitrogen. A gas sample was extracted from the centroid of the stack using a stainless steel probe fitted with a particulate filter. The probe, sample lines, and orsat were purged sufficiently to obtain a representative grab sample for analysis.
METHOD 3A: DETERMINATION OF OXYGEN AND CARBON DIOXIDE CONCENTRATIONS IN EMISSIONS FROM STATIONARY SOURCES
(INSTRUMENTAL ANALYZER PROCEDURE)
A gas sample was continuously extracted from the stack using a heated probe and sample line. The sample was transferred to a oxygen analyzer for analysis of oxygen concentration. Analyzer output was continuously recorded by a computer data acquisition system. Results form the oxygen monitor were used for reference purposes only and were not used to determine stack gas molecular weight.
METHOD 4: DETERMINATION OF MOISTURE CONTENT IN STACK GASES
A gas sample was extracted from the stack using a heated glass probe fitted with a particulate filter. The sample gas then passed through a series of four impingers immersed in an ice bath. The first two impingers contained measured volumes of water, the third was empty, and the fourth contained a known weight of silica gel. Any water vapor in the gas stream was condensed and trapped in the impingers. Moisture was determined gravimetrically.
METHOD 5: DETERMINATION OF PARTICULATE EMISSIONS FROM STATIONARY SOURCES
A gas sample was withdrawn isokinetically from the source using a heated probe. The gas was drawn through a heated glass fiber filter that collected particulate and any material that condensed at our above the filtration temperature. The gas then passed through an impinger train immersed in an ice bath. The train consisted of two impingers containing known amounts of water, one empty impinger, and one impinger packed with silica gel.
Sample flow rate was established using a leak free diaphragm pump and controlled using a valve. A calibrated dry gas meter was used to determine the total gas sample volume.
After sampling, the filter was recovered from the filter holder. The front half of the filter holder and probe were washed with acetone and the washings were poured into a sample bottle. Sample containers were labeled and sealed.
METHOD 6: DETERMINATION OF SULFUR DIOXIDE EMISSIONS FROM STATIONARY SOURCES
A gas sample was withdrawn isokinetically from the source using a heated probe an drawn through a heated glass fiber filter that collected particulate and any material that condensed at or above the filtration temperature. The gas then passed through an impinger train immersed i an ice bath. The train consisted of one impinger containing 3% hydrogen peroxide, and one impinger packed with silica gel. Sample flow rate was established using a leak free diaphragm pump and controlled using a valve. A calibrated dry gas meter was used to determine the total gas sample volume.
After sampling, the impinger train was purged with ambient air for 15 minutes. The contents of the first impinger was discarded and impingers 2 and 3 were collected as one sample. Sample containers were labeled and sealed.
METHOD 7E: DETERMINATION OF NITROGEN OXIDES EMISSIONS FROM STATIONARY SOURCES
A gas sample was continuously extracted from the stack at a centroidal sampling point. The sample was transferred through a heated sample line to continuous chemiluminescence analyzer for the determination of oxides of nitrogen concentration.
METHOD 10: DETERMINATION OF CARBON MONOXIDE EMISSIONS FROM STATIONARY SOURCES
A gas sample was continuously extracted from the stack at a centroidal sampling point. The sample was transferred through a heated sample line to a continuous nondispersive infrared analyzer for the determination of carbon monoxide concentration.
METHOD 25A: DETERMINATION OF TOTAL GASEOUS ORGANIC CONCENTRATION USING A FLAME IONIZATION ANALYZER
A gas sample was continuously extracted from the source at a centroidal sampling point. The sample was transferred through a heated sample line to a continuous analyzer equipped with a flame ionization detector.
ANALYTICAL TECHNIQUE
All sample analysis were conducted following EPA methodology. A brief description follows for each method employed.
METHOD 5: DETERMINATION OF PARTICULATE EMISSIONS FROM STATIONARY SOURCES
Particulate catch was determined gravimetrically. The filter was oven conditioned at 350 deg-F. and weighed before and after sampling and the difference in weight determined the particulate filter catch. The probe and front half of the filter holder were washed with acetone. The probe wash catch was determined by the total solids in the wash minus the DI water blank. Total particulate catch was determined by the addition of the filter catch and the probe wash catch.
METHOD 6: DETERMINATION OF SULFUR DIOXIDE EMISSIONS FROM STATIONARY SOURCES
Sulfur dioxide concentration in the sample was determined by titration.
METHOD 7: DETERMINATION OF NITROGEN OXIDES EMISSIONS FROM STATIONARY SOURCES
All samples collected were analyzed at the laboratory using a continuous chemiluminescence analyzer. The analyzer was calibrated using as standards prepared by EPA protocol number 1, traceable to NBS standards.
METHOD 10: DETERMINATION OF CARBON MONOXIDE EMISSIONS FROM STATIONARY SOURCES
All samples collected were analyzed at the laboratory using a continuous nondispersive infrared analyzer. The analyzer was calibrated using gas standards prepared by EPA protocol number 1, traceable to NBS standards.
METHOD 25A: DETERMINATION OF TOTAL GASEOUS ORGANIC CONCENTRATION USING A FLAME IONIZATION ANALYZER
Total hydrocarbons were determined using a flame ionization analyzer. The analyzer was calibrated using gas standards prepared by EPA protocol number 1, traceable to NBS standards. Results are reported as volume concentration equivalents of the calibration gas, methane.
Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
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A hazardous waste disposal system includes a rotary kiln heated with an atomizing burner which mixes fuel such as diesel oil with air and injects the burning mixture into the kiln. An afterburner section is similarly fueled with an atomizing burner. An upstanding scrubber receives exit gases and removes particulate matter using water spray across multiple frusto conical shaped baffles on increasing diameter. Cyclone vanes produce a spinning effect to the exit gases during scrubbing.
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This invention relates to a snap hinge of the type which may be used for attaching a furniture door to the carrier wall of a piece of furniture and particularly to a hinge of the type formed by two pivoting link members comprising what might be called a quadrilateral link mechanism.
Hinges of this general type are known and these snap hinges have the characteristic that the opening or closing force, respectively, is only exerted within a selected range.
A most desirable characteristic in such a hinge would be that the hinge does not exert a force on the door throughout substantially the entire range of its pivotal movement, thus exerting neither an opening or a closing force in that range of movement. This range should extend between the open position of the door and a position shortly before the door is in a closed position. Only when this position is reached, i.e. shortly before the closed position, should the spring exert a closing force. Such a characteristic enables the door to remain stationary in all positions within the opening range which extends from the complete open position up to shortly before the closed position, and the door thus neither opens or closes by itself. Only when the door has been pivoted from the open position in a direction towards the closed position to such an extent that it is at a position shortly before the closed position, should the closing force which is to maintain the door positively closed after the closing process commence.
Prior art constructions have not provided a satisfactory hinge possessing these desirable characteristics. Thus, the invention has evolved from the problem of trying to make a hinge which is more stable and to allow a more precise functioning of the hinge.
SUMMARY OF THE INVENTION
Accordingly, an object of this invention is to provide a hinge unit having a pair of pivotally mounted link members including cam means for permitting a door with which the hinge unit is associated to move through substantially its full range of movement without any opening or closing force on the door and then to have a positive closing force exerted thereon when the door is close to a closed position.
Another object of this invention is to provide a hinge unit having a pair of pivotally mounted link members and a spring actuated mechanism associated with one of said link members for urging a door with which the hinge unit is associated to a closing position.
Another object is to provide a hinge unit having a pair of pivotally mounted link members and a spring biased mechanism associated with a cam mechanism on one of said link members for assuring positive closing of a door unit with which said hinge unit is associated.
Other objects and advantages of the invention will become more apparent when considering the following description and accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a horizontal section of a snap hinge embodying the invention herein showing the hinge mounted on a furniture wall and a door with the door in a closed position;
FIG. 2 is a vertical section showing the hinge of FIG. 1 mounted on a furniture wall and a door with the door in a partially open position;
FIG. 3 is a vertical section of the hinge member embodying the invention herein and taken through line 2--2 of FIG. 1;
FIG. 4 is an exploded view in perspective of the inner link of the hinge of FIG. 1 showing one of the cam control discs detached from the link member;
FIG. 5 shows a cam disc having detents formed in the surface thereof.
DESCRIPTION OF PREFERRED EMBODIMENT
As can be seen from the drawing, the snap hinge serves for attaching a door 1 to a carrier wall 2 of a piece of furniture. The hinge comprises a dish-shaped housing 3 which is inserted into a corresponding recess 3A of the door, and a carrier arm portion 4 which is constructed as a longitudinally extending inverted U-shaped carrier arm. In FIG. 1 the drawing shows only that end of the carrier arm 4 which is disposed adjacent the snap joint of the hinge.
The two portions, the dish-shaped housing portion 3 and carrier arm 4, are interconnected by a quadrilateral link mechanism comprising an inner link member 5 and an outer link member 6. The inner link 5 is pivotally mounted in the dish-shaped housing 3 by means of a pivot pin 7, and within the carrier arm 4 by means of a pivot pin 8. In the same manner, the outer link 6 is pivotally mounted within the housing 3 by means of a pivot pin 9 and within the carrier arm 4 by means of a pivot pin 10.
An essential element of this snap hinge is the spring biased lever arm 11 which is pivotally mounted at one of its ends by means of the pivot pin 12 attached within the carrier arm 4. The pivoting end of the lever arm 11 is under the effect of a compression spring 13 which urges this pivoting end against a cam means. The cam means is attached to the inner link 5 and comprises two identical laterally spaced cam control discs 14 disposed parallel to each other and which are attached to the end of the pivotal mounting portion of the link 5 which fits around the pivot pin 8. The outer periphery of these control discs 14 define cam surfaces whose path or shape determines the operational characteristics of the hinge. The control discs 14 may be formed integrally with the link 5. They may also, however, be independent elements which may be attached to the link 5, for instance by way of riveting, welding or other suitable means. For illustrative purposes one of the two control discs 14 is shown detached from the link 5 in FIG. 4, while the other control disc is shown connected to the inner link 5.
Cam surfaces 14A and 14B are formed on the edges of the control discs 14. These cam surfaces 14A of the two control discs 14 extend coaxially to the pivot pin 8 throughout the greater part of the periphery thereof as substantially circular arcs. The lever arm 11 of the described embodiment is provided with a pair of rollers 15 mounted at the ends of pin 11A extending transversely through lever are 11 in order to reduce friction.
It can be seen from the FIGS. 1 and 2 that the rollers 15 travel along the substantially circular arc cam surfaces 14A during the greater part of the travel of the door during its swinging movement. When the door is about to close, however, the roller 15 travels on cam surface 14B, i.e. on that part of the two control surfaces within which the distance of the cam surface from the axis of the pivot pin is shorter. It is apparent from viewing FIGS. 1 and 2 that a closing force starts at the instant in which the roller 15 moves past the turning point 16 of the control curve which lies between the cam surfaces 14A and 14B. When the rollers 15 are in contact with the cam surfaces 14B a closing force starts, so that the hinge is firmly urged into a position in which the door is in a closed position as shown in FIG. 1. The total control curve comprising cam surfaces 14A and 14B and intermediate point 16 is the most important feature of the hinge in accordance with this invention.
It should be mentioned that surfaces 14A of the cam control discs 14 may also be provided with one or more small recesses or detents 17 in the center range and/or in the range of the open position for selectively holding the door in selected open positions as the rollers 15 are received in those recesses 17.
In the hinge shown here as a preferred embodiment the door remains open in almost its entire open range, and does not strike open entirely or close with an impact. The force closing the door has an effect only shortly before the closed position and will then cause the door to be closed entirely automatically and then remain positively closed.
The present invention embodies a particularly reliable construction for hinges with quadrilateral link mechanism due to the application of two control discs 14 which are arranged at as large a distance from one another as possible at the edges of the link 5. This provides a stable guidance for the two pressure rollers 15. It is possible in this manner to utilize the entire width of the pivotal mounting portion of the link 5 as a bearing surrounding the pivot pin 8.
In the case where the control discs 14 are first produced as separate parts, FIG. 4 shows a perspective view of the inner link 5 with one of the two control discs 14 formed integrally with the link while the other disc has been shown separately. It can be seen that these control discs can be attached to the edges of the link since the edges have been provided with recesses 18 for this reason. The fixed connection of the attached control discs 14 with the link 5 can be effected by way of peening the margins.
Although the operation of the hinge embodying the invention should be clear from the above description the operation will be briefly summarized. Starting with the door 1 in a closed position as shown in FIG. 1, the compression spring 13 urges the lever 11 downwardly pressing the rollers 15 against cam surfaces 14B thereby urging the control discs 14 and the link 5 counterclockwise about pivot pin 8 to a positive closing position. When the door is slightly opened as shown in FIG. 2 the lever 11 is urged upwardly as the clockwise rotation of control discs 14 and link 5 causes the rollers 15 to ride upwardly on the cam surfaces 14B until they hit intermediate point 16. Further opening movement of the door 1 allows the rollers 15 to ride on the cam surfaces 14A with an equal pressure on the spring 13 because all points on the cam surfaces 14A are equidistant from the axis of the pivot pin 8, at least until the door 1 has reached a full open position. This allows the door to be placed at any of a number of selected open positions and remain at that particular open position without any force tending to further open or close the door.
When the door is to be closed the opposite takes place. When the control disc has rotated far enough counterclockwise to reach point 16 and an almost closed position compression spring 13 takes over and automatically makes rollers 15 ride down cam surfaces 14B to urge control discs 14 and link 5 further counterclockwise bringing the door 1 positively to a closed position.
While a preferred embodiment of the invention has been disclosed it will be appreciated that this has been shown by way of example only, and the invention is not to be limited thereto as other variations will be apparent to those skilled in the art and the invention is to be given its fullest possible interpretation within the terms of the following claims.
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A snap hinge for use in connecting furniture doors, for example, to a furniture wall utilizing a pair of pivotally mounted link members and including a spring biased mechanism and a cam control unit associated with said link members for assuring positive closing of a door with which the snap hinge is associated.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No. 10/025,767 filed Dec. 26, 2001, which is a continuation of U.S. application Ser. No. 09/520,843 filed Mar. 8, 2000 that issued as U.S. Pat. No. 6,394,784 on May 28, 2002, the entire disclosures of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to injection molding and more particularly to an injection molding nozzle having an integral electrical heating element surrounded by layered dielectric insulation.
[0004] 2. Related Art
[0005] Heaters for injection molding and hot runner applications are known in the prior art, as demonstrated amply by the following U.S. Pat. Nos. 2,991,423, 2,522,365, 2,769,201, 2,814,070, 2,875,312, 2,987,300, 3,062,940, 3,550,267, 3,849,630, 3,911,251, 4,032,046, 4,403,405, 4,386,262, 4,557,685, 4,635,851, 4,644,140, 4,652,230, 4,771,164, 4,795,126, 4,837,925, 4,865,535, 4,945,630, and 4,981,431.
[0006] Heaters are of course also amply known in non-injection molding applications, as shown for example in U.S. Pat. Nos. 2,088,586, 2,378,530, 2,794,504, 4,438,322 and 4,621,251.
[0007] There are in general three types of heaters known for use in the hot runner nozzles. The first is so-called “integral heaters” which are embedded or cast in the nozzle body. Examples of such nozzles are disclosed in the following patents: U.S. Pat. No. 4,238,671, U.S. Pat. No. 4,386,262, U.S. Pat. No. 4,403,405 and EP 765728. The second is so-called “independent external heaters” which have. their own support and that can be removed and replaced. Essentially, in such a design, shown in FIG. 1 a, the heating element H is external to the nozzle body N. Heating element H comprises a resistance wire W surrounded by electrical insulating material E and is encased in a steel casing C. Examples of such nozzles are disclosed in the following patents: U.S. Pat. No. 3,553,788, U.S. Pat. No. 3,677,682, U.S. Pat. No. 3,831,004, U.S. Pat. No. 3,912,907, U.S. Pat. No. 4,588,367, U.S. Pat. No. 5,360,333, U.S. Pat. No. 5,411,393, U.S. Pat. No. 5,820,900, EP 748678, EP 963829 and EP 444748. The third is so-called “attached external heaters” which are positioned spirally around the exterior of the nozzle or the nozzle tip but cannot be removed therefrom by reason of being brazed or embedded in the nozzle surface. Referring to FIG. 1 b, heating element H′ is embedded in a groove G′ in nozzle body N′. Examples of such nozzles are disclosed in the following patents: U.S. Pat. No. 4,557,685, U.S. Pat. No. 4,583,284, U.S. Pat. No. 4,652,230, U.S. Pat. No. 5,226,596, U.S. Pat. No. 5,235,737, U.S. Pat. No. 5,266,023, U.S. Pat. No. 5,282,735, U.S. Pat. No. 5,614,233, U.S. Pat. No. 5,704,113 and U.S. Pat. No. 5,871,786.
[0008] Electrical heaters have been also used in the design of the so-called hot runner probes. Unlike the hot runner nozzles the hot runner probes do not comprise the melt channel. The probes are located inside the melt channel of the nozzle and thus create an annular flow. The melt is heated from the inside and this heating approach is not applicable to all materials and applications. Examples of such nozzles are disclosed in the following U.S. Pat. Nos. 3,800,027 3,970,821, 4,120,086, 4,373,132, 4,304,544, 4,376,244, 4,438,064, 4,492,556, 4,516,927, 4,641,423, 4,643,664, 4,704,516, 4,711,625, 4,740,674, 4,795,126, 4,894,197, 5,055,028, 5,225,211, 5,456,592, 5,527,177 and 5,504,304.
[0009] Injection molding nozzles having integral heaters typically have electrical heating elements, wound spirally around the nozzle, which offer an efficient response to the many critical process conditions required by modern injection molding operations. There has been a continuous effort in the prior art, however, to improve the temperature profile, the heating efficiency and durability of such nozzles and achieve an overall reduction in size. Most of these efforts have been aimed at improving the means of heating the nozzle.
[0010] For example, U.S. Pat. No. 5,051,086 to Gellert discloses a heater element brazed onto the nozzle housing and then embedded in multiple layers of plasma-sprayed stainless steel and alumina oxide. To avoid cracking of the ceramic layers caused by excessive thickness and the differing thermal properties of the ceramic and the stainless steel, Gellert employs alternating thin layers of stainless steel and alumina oxide. The heating element of Gellert is nickel-chrome resistance wire (i.e. see W in FIGS. 1 a and 1 b herein) extending centrally through a refractory powder electrical insulating material (i.e. see E in FIGS. 1 a and 1 b ), such as magnesium oxide, inside a steel casing (i.e. see C in FIGS. 1 a and 1 b ). The heating element is integrally cast in a nickel alloy by a first brazing step in a vacuum furnace, which causes the nickel alloy to flow by capillary action into the spaces around the heater element to metallurgically bond the steel casing of the element to the nozzle body. This bonding produces very efficient and uniform heat transfer from the element to the nozzle body.
[0011] Nozzles with this type of electrical heaters, however, are often too big to be used in small pitch gating due to the size of the insulated heater required. These heaters are also generally expensive to make because of complex machining required. Also, the manufacturing methods to make these nozzle heaters are complex and therefore production is time consuming.
[0012] U.S. Pat. No. 5,955,120 to Deissler which discloses a hot runner nozzle with high thermal insulation achieved by coating the electrical heater with layers of a thermally insulation materials (mica or ceramic) and high wear resistance material (titanium). Like Gellert, the heater element of Deissler has its own electrical insulation protection and thus can be placed in direct contact with the metallic nozzle body (see FIG. 2 of Deissler). Also the heater element of Deissler is attached to the nozzle by casting (brazing) a metal such as brass. Deissler is thus similar to Gellert in that it discloses an insulated and brazed heater element. Again, as with Gellert, such a device requires many additional steps to braze and insulate the heater and is therefore time consuming. Also, as with Gellert, the use of an insulated element makes the size of the heated nozzle not well suited for small pitch applications.
[0013] In an attempt to reduce nozzle size, U.S. Pat. No. 5,973,296 to Juliano shows a thick film heater applied to the outside surface of an injection nozzle. The nozzle heater comprises a dielectric film layer and a resistive thick film layer applied directly to the exterior cylindrical surface of the nozzle by means of precision thick film printing. The thick film is applied directly to the nozzle body, which increases the nozzle's diameter by only a minimal amount. Flexibility of heat distribution is also obtained through the ability to apply the heater in various patterns and is, thus, less limited than spiral designs.
[0014] There are limitations to the thick film heater, however. Thermal expansion of the steel nozzle body during heating can cause unwanted cracking in the film layers due to the lower thermal expansion of the film material. This effect is particularly acute after a large number of injection cycles. The cracks could affect the resistive film heater because it is not a continuous and homogeneous material (as is a wire), but rather the fine dried powder of the conductive ink, as disclosed in Juliano '296.
[0015] Another heated nozzle design is disclosed in U.S. Pat. No. 4,120,086 to Crandell. In one embodiment, Crandell '086 discloses an electrically heated nozzle having an integral heater comprising a resistance wire heater disposed between two ceramic insulating layers. The Crandell '086 nozzle is made by wrapping a metal nozzle body with flexible strips of green (i.e., unsintered) ceramic particles impregnated in heat dissipatable material, subsequently winding a resistance wire heating element around the wrapped green layer, wrapping a second layer of the flexible strips of green ceramic particles thereover, heat treating the assembly to bake out the heat dissipatable material and sinter the ceramic particles together, and then compacting the assembly to eliminate air voids in the assembly. In U.S. Pat. No. 4,304,544, also to Crandell, the inventor further describes the flexible green ceramic strips as comprising a body of green ceramic insulator particles which are impregnated in a heat dissipatable binder material. In the green state, such strips are pliable and bendable, permitting them to be wrapped around the metal nozzle core, but when baked, the strips become hard and the particles agglomerate into a mass.
[0016] The Crandell '086 and '544 nozzle has relatively thick ceramic layers, employs an awkward process for applying the ceramic layers and requires additional heat treatment steps in fabrication, Crandell '086 concedes that the baking step is time consuming (see column 5, lines 20-25) and therefore admits that the design is less preferable than other embodiments disclosed in the patent which do not utilize this method. Also, as mentioned above, it is desirable to reduce nozzle size, which is not possible with the thick ceramic strips of Crandell '086 and '144 .
[0017] The use of ceramic heaters for both hot runner nozzle heaters and hot runner probe heaters is also disclosed in U.S. Pat. No. 5,504,304 to Noguchi. Noguchi, like Juliano, uses a printing method to form an electrical resistive wire pattern of a various pitch from a metal or a composite paste. A ceramic heater embodiment for a nozzle probe (shown in FIG. 1 of Noguchi) is made by printing various electrical resistive patterns shown in FIGS. 3-4 of Noguchi. Noguchi discloses a method whereby a mixture of insulating ceramic powder such as silicon carbide (SiC), molybdenum silicide (MOSi 2 ) or alumina (A 1 2 O 3 ) and silicon nitride (SiN), and electrically conductive ceramic powder such as titanium nitride (TiN) and titanium carbide (TiC is sintered and kneaded into a paste, which is then printed in a snaking manner on the external surface of a cylindrical insulating ceramic body, as shown in FIG. 3 of Noguchi. The printing state is made denser in certain areas and, by so controlling the magnitude of the so-called “wire density,” a temperature gradient is given to the heater. The heater pattern can be formed using metals such as tungsten, molybdenum, gold and platinum. A ceramic heater embodiment for a hot runner nozzle is also disclosed in Noguchi (see FIG. 14 of Noguchi). This self-sustained ceramic heater is also made by wire-printing using the same paste or metals. The heater is placed over the nozzle body and is then sintered and kneaded into a paste comprising a mixture of insulation ceramic powder such as silicon carbide, molybdenum silicide or alumina and conductive ceramic powder such as titanium nitride and titanium carbide. The paste is printed in a single snaking line on the part where, again, the heater pattern is formed by applying temperature gradients by varying the magnitude of wire density across the part.
[0018] Although Noguchi introduces a wire-printing method to achieve a certain heat profile along the nozzle it does not teach or show how this wire-printing method is actually implemented. More detailed information about this wire-printing method is provided by the patentee's (Seiki Spear System America, Inc.) catalogue entitled “SH-1 Hot Runner Probe” (undated). According to the catalogue, the circuit pattern, which provides the resistance for heating, is screen printed direction onto a “green” or uncured ceramic substrate. The flexible “green” substrate with the printed circuit is wrapped around an existing ceramic tube and the complete unit is fired and cured to produce a tubular heater. The resistive circuit pattern is encased within the ceramic between the tube and the substrate and has no exposure to the outside atmosphere. The thermocouple is inserted through the center of the tubular heater and positioned in the tip area. Thermocouple placement in the probe tip gives direct heat control at the gate. The ceramic heater unit is then fixed outside the probe body. Thus, this Seiki Spear method of making a ceramic heater body according to Noguchi including a printed-wire is similar to the method disclosed in Crandell ' 086 , with the exception that Crandell uses a self-sustained resistance wire wound spirally around the nozzle between two “green” ceramic layers. As with Crandell, as well, an additional sintering step is required to sinter the green ceramic layers.
[0019] Accordingly, there is a need for a heated nozzle which overcomes these and other difficulties associated with the prior art. Specifically, there is a need for a heated nozzle which is simpler to produce and yields a more compact design.
SUMMARY OF THE INVENTION
[0020] The present invention provides an injection molding nozzle which is smaller in diameter than most prior art nozzles but which does not sacrifice durability or have the increased manufacturing costs of previous small diameter nozzles. Further the nozzle of the present invention is simpler, quicker and less costly to produce than prior art nozzles and minimizes the number of overall steps required in production. In particular, the need for heat treating the dielectric materials of the heater is removed entirely, saving time, money and hassle in fabrication. Further, the apparatus of the present invention provides a removable and/or replaceable cartridge heater design which offers the advantage of low-cost repair or replacement of a low cost heater component, rather than wholesale replacement of an intricately and precisely machined nozzle. The methods of the present. invention similarly provide reduced and simplified steps in manufacturing, as well as permitting precise temperature patterns to be achieved a nozzle more simply than with the prior art.
[0021] In one aspect, the present invention provides an injection molding nozzle comprising a nozzle body having an outer surface and at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0022] In a second aspect, the present invention provides an injection molding nozzle comprising a nozzle body assembly having an outer surface and at least one melt channel through the assembly, the assembly having a core and a surface layer disposed around the core, the surface layer forming at least a portion of the nozzle body assembly outer surface, the core being composed of a first metal and the surface layer being composed of a second metal, the second metal having a higher thermal conductivity than the first metal, a first insulating layer disposed on the nozzle body assembly outer surface so as to substantially cover at least a portion of the outer surface, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element and a second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer.
[0023] In a third aspect, the present invention provides an injection molding nozzle comprising a nozzle body having an outer surface and at least one melt channel through the body, a first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the first insulating layer is between 0.1 mm and 0.5 mm in thickness.
[0024] In a fourth aspect, the present invention provides an injection machine for forming a molded article, the machine comprising a mold cavity, the mold cavity formed between a movable mold platen and a stationary mold platen, at least one injection molding nozzle connectable to a source of molten material and capable of feeding molten material from the source to the mold cavity through at least one melt channel therethrough, the at least one nozzle injection molding having a nozzle body having an outer surface and the at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0025] In a fifth aspect, the present invention provides an injection mold to form an article, the mold comprising a mold half capable of communication with a mold manifold, at least one injection molding nozzle in flow communication with the mold half through at least one melt channel, the at least one nozzle injection molding having a nozzle body having an outer surface and the at least one melt channel through the body, a first insulating layer having a chemical composition, the first insulating layer disposed on the nozzle body outer surface so as to substantially cover at least a portion of the nozzle body, at least one wire element disposed exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the wire element, a second insulating layer having a chemical composition, the second insulating layer disposed over the first insulating layer and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are disposed on the nozzle body.
[0026] In a sixth aspect, the present invention provides an injection molding nozzle comprising the steps of providing a nozzle body, the nozzle body having an outer surface and at least one melt channel through the body providing a first insulating layer on the outer surface of the nozzle body, the first insulating layer having a chemical composition, the first insulating layer substantially covering at least a portion of the nozzle body outer surface, positioning at least one wire element exterior to and in contact with the first insulating layer, the at least one wire element being connectable to a power supply capable of heating the at least one wire element, providing a second insulating layer on the first insulating layer and the at least one wire element, the second insulating layer having a chemical composition, the second insulating layer substantially covering the at least one wire element and at least a portion of the first insulating layer, and wherein the chemical compositions of the first and second insulating layers remain substantially unchanged once the layers are provided on the nozzle body.
[0027] In a seventh aspect, the present invention provides an injection molding nozzle comprising the steps of providing a nozzle body, the nozzle body having an outer surface and at least one melt channel through the body positioning a self-supporting insulating sleeve around the nozzle body, the sleeve substantially covering at least a portion of the nozzle body outer surface positioning at least one wire element exterior to and in contact with the insulating sleeve, the at least one wire element being connectable to a power supply capable of heating the at least one wire element, providing a second insulating layer on the insulating sleeve and the at least one wire element, the second insulating layer substantially covering the at least one wire element and at least a portion of the insulating sleeve.
BRIEF DESCRIPTION OF THE FIGURES
[0028] For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example to the accompanying drawings.
[0029] The drawings show articles made according to a preferred embodiment of the present invention, in which:
[0030] [0030]FIGS. 1 a and 1 b are partial sectional views of heated nozzle configurations according to the prior art;
[0031] [0031]FIG. 2 is a sectional view of a portion of an injection molding system showing a heated nozzle according to a preferred embodiment of the present invention;
[0032] [0032]FIG. 3 is an enlarged sectional view of the nozzle of FIG. 2;
[0033] [0033]FIG. 4 is a further enlarged and rotated (90′ counter-clockwise) sectional view of the heater assembly of the nozzle of FIG. 2;
[0034] [0034]FIG. 5 is an enlarged sectional view, similar to FIG. 4, of an alternate embodiment of a nozzle heater assembly according to the present invention;
[0035] [0035]FIG. 6 is an enlarged sectional view, similar to FIG. 4, of another alternate embodiment of a nozzle heater assembly according to the present invention;
[0036] [0036]FIG. 7 is an enlarged sectional view, similar to FIG. 4, of a further alternate embodiment of a nozzle heater assembly according to the present invention;
[0037] [0037]FIG. 8 is an enlarged sectional view, similar to FIG. 4, of a yet further alternate embodiment of a nozzle heater assembly according to the present invention;
[0038] [0038]FIG. 9 is an exploded isometric view of an alternate embodiment of the nozzle heater of the present invention;
[0039] [0039]FIG. 10 is a sectional view of a further embodiment of the nozzle heater of the present invention;
[0040] [0040]FIG. 11 is an enlarged sectional view of another nozzle embodiment employing a heater according to the present invention;
[0041] [0041]FIG. 12 a is an isometric view of a straight wire element for use as a heater element of the present invention;
[0042] [0042]FIG. 12 b is an isometric view of a coiled wire element for use as a heater element of the present invention;
[0043] [0043]FIG. 13 a is an isometric view of a doubled and twisted straight wire element for use as a heater element of the present invention; and
[0044] [0044]FIG. 13 b is an isometric view of a doubled, coiled wire element for use as a heater element of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0045] A multi-cavity injection molding system made in accordance with the present invention is shown in the Figures generally at M. Referring to FIG. 2, a portion of injection molding system M is shown. A melt passage 10 extends from a common recessed inlet 12 in a manifold extension 14 to an elongated manifold 16 where it branches out to a number of outlets 18 . As can be seen, each branch 20 of melt passage 10 extends through steel nozzle 22 , having a central melt bore 24 in communication with melt passage outlet 18 from manifold 16 to a gate 26 leading to each cavity 28 . Nozzle 22 is a heated nozzle having a heater 30 according to a preferred embodiment of the invention, as described in greater detail below.
[0046] Manifold 16 is heated by a heating element 32 , which may be integrally brazed into it. Manifold 16 is held in place by a central locating ring 34 and insulating pressure pads 36 . Locating ring 34 bridges an insulative air space 38 between manifold 16 and a cooled spacer plate 40 . Pressure pads 36 provide another insulative air space 42 between manifold 16 and a cooled clamp plate 44 . Spacer plate 40 , clamp plate 44 and cavity plate 46 are cooled by pumping cooling water through a plurality of cooling conduits 48 . Clamp plate 44 and spacer plate 40 are secured in place by bolts 50 which extend into cavity plate 46 . Manifold extension 14 is held in place by screws 52 and a locating collar 54 which is secured to the clamp plate 44 by screws 56 .
[0047] Each nozzle 22 is seated in a well 58 in spacer plate 40 . An insulative air space 64 is provided between heated nozzle 22 and the surrounding cooled spacer plate 40 .
[0048] Referring to FIGS. 2 and 3, nozzle 22 has a body 68 having a steel central core portion 70 , an outer surface 72 , and a tip 74 , which is seated in gate 26 . Tip 74 has a flow channel 76 which is aligned with central melt bore 24 . Nozzle 22 is seated and secured in manifold 16 by a threaded portion 78 . Heater assembly 30 has an electrical resistive wire heating element 80 , having a cold pin connections 82 for connecting wire element 80 to a power supply (not shown). Heater assembly 30 also has a first insulating layer 84 and a second insulating layer 86 disposed on either side of wire element 80 , so as to “sandwich” element 80 therebetween. First layer 84 is positioned on core 70 , with wire element 80 wrapped therearound, and second layer 86 positioned thereover. An outer steel layer 88 is provided to finish nozzle 22 . These layers are provided in a manner as will be described in more detail below.
[0049] Wire element 80 is a simple, bare, electrically and thermally uninsulated wire, preferably of thirty (30) gauge chromium nickel, though any wire material having resistive heating characteristics may be employed. Wire element 80 is preferably wrapped around nozzle 22 , and may be provided in any arrangement which provides the temperature distribution desired for a particular application. For example, in the embodiment of FIG. 3, successive windings of wire element 80 are closer together at the ends of nozzle 22 , where more heat is typically required, with a more spaced distribution occurring in the central portion of nozzle 22 .
[0050] According to the present invention, first layer 84 and second layer 86 are dielectric materials which can be applied in a “finished” (i.e. “non-green”) state to the nozzle body. In other words, the dielectric material does not require additional heat treating steps once it is applied to the nozzle assembly, and thus has a chemical composition which does not change after it is applied to the apparatus and the material does not require heat treating of sintering to achieve its “finished” state. In addition to this constraint, first layer 84 is also preferably a dielectric material which can withstand the high operating temperatures and heater wattages experienced in hot runner injection molding. As one skilled in the art will understand, the dielectric is preferably a good thermal conductor with low heat capacity, a combination which encourages rapid heating (and cooling) with maximum efficiency. The dielectric should also be a good electrical insulator, since wire element is otherwise uninsulated from nozzle 22 . The choice of material depends also on the temperature target for the molten material which will flow through the melt channel of the nozzle.
[0051] Illustrative of the dielectric materials which can be used in the practice of this invention are: aluminum oxide; magnesium oxide; mica coatings; Vespel™ (trade mark of E. I. Du Pont de Nemour & Company), graphite; alumina; alumina-silica; zirconia-based materials, such as tetragonal zirconia polycrystals (TZP) partially stabilized zirconia (PSZ), fully stabilized zirconia (FSZ), transformation toughened ceramics (TTC), zirconia toughened alumina (ZTA) and transformation toughened zirconia (TTZ); Cerama-Dip™ 538N (trade mark of Aremco Products Inc.), a zirconium silicate-filled water-based high temperature dielectric coating for use in insulating high-power resistors, coils and heaters; and Ceramacoat™538N (trade mark of Aremco Products Inc.) is a silica based, high temperature dielectric coating for use in insulating induction heating coils. Aluminum oxide is a preferred material because of its relatively high thermal conductivity.
[0052] Second layer 86 is provided to protect wire element 80 from the deleterious effects of the atmosphere, such as oxidation and corrosion, and to insulate the exterior of nozzle 22 electrically and thermally, so as to direct the output of heater assembly 30 towards the melt in flow channel 76 . Second layer 86 may be made from the same dielectric material as first layer 84 or a different material. In some applications, it may be desirable to use different materials. For example, the first layer 84 may be fabricated from a material having good electric insulating properties but high heat conductive characteristic, while the second layer 86 is of a material having high electric insulating properties and high heat insulating properties, so that the heat is directed to the central melt bore 24 within body 68 , while outer layer 88 remains cooler. The use of the same material, preferably aluminum oxide, for first layer 84 and second layer 86 is preferred.
[0053] First layer 84 and second layer 86 may be provided as particles or a liquid sprayed onto the nozzle apparatus, as a liquid “painted” onto the apparatus or as a solid, pre-fabricated, self-supporting sleeve, as described in more detail below. The layers may be provided in thicknesses as desired to suit a particular application. Thicknesses of the layers can range from 0.1 mm to 3 mm, and thicker, depending on the amount of insulating, overall nozzle diameter and method of fabrication desired, as will be described further below. Thicknesses in the range of 0.1 mm to 0.5 mm are preferred.
[0054] Outer layer 88 may be applied by spraying or by shrink-fitting a sleeve on second layer 86 . Outer layer 88 may have any desired thickness, though a thickness of about 1.5 mm is preferred.
[0055] Referring to FIGS. 4 - 7 , other embodiments of a nozzle heater according to the present invention are shown. In the embodiment of FIG. 5, a secondary wire element 90 is provided around second layer 86 , protected by a third insulating layer 92 . In this three-layer embodiment, second layer 86 is preferably a good heat conductor and electrical insulator while third layer 92 is a dielectric having good thermal insulating characteristics. Third layer 92 can be chosen from the same set of materials as described above for layers 84 and 86 . This embodiment permits a higher wattage heater to be obtained, at the obvious expense of a slightly larger nozzle diameter. Alternatively, secondary wire element 90 can provide redundancy for operational, use if and when the primary wire element fails. FIG. 6 shows a configuration similar to FIG. 4, but with integral temperature sensors or thermocouple wire 94 and 96 positioned between first layer 84 and second layer 86 , wound spirally around nozzle 22 adjacent wire element 80 . Inclusion of thermocouples 94 and 96 allow for exacting temperature control in nozzle 22 , as will be understood by one skilled in the art. The thermocouples may be disposed immediately adjacent wire element 8 , as shown in FIG. 6, or may be provided between second layer 86 and third insulating layer 92 , as depicted in FIG. 7. In this embodiment, second layer 86 and third layer 92 preferably have similar characteristics as described above for the FIG. 5 embodiment.
[0056] Referring to FIG. 8, in a further alternate embodiment, a metal surface layer 98 is provided on outer surface 72 , between nozzle core 70 and first layer 84 . Surface layer 98 is a layer of a metal having a higher thermal conductivity than steel nozzle body 68 , such as copper and alloys of copper. Surface layer 98 thus promotes a more even distribution of heat from heater assembly 30 to the pressurized melt in central melt bore 24 . Surface layer 98 may be applied by spraying or by shrink-fitting a sleeve on core 70 . Surface layer 98 may have a thickness of between 0.1 mm to 0.5 mm, or greater if desired.
[0057] Referring to FIG. 9, in an alternate embodiment of the present invention, nozzle 22 ′ has a core 70 ′, a surface layer 98 ′ and a heater assembly 30 ′, which is composed of a first layer 84 ′, a wire element 80 ′, a second layer 86 ′ and an outer layer 88 ′. In this embodiment, surface layer 98 ′, first layer 84 ′, second layer 86 ′ and outer layer 88 ′ in fact, self-supporting, substantially rigid, annular telescoping sleeve components 98 a, 84 a, 86 a, and 88 a, respectively, which are pre-fabricated, prior to assembly of nozzle 22 ′, according to a method of the present invention, described below. This sleeve construction permits a heater assembly 30 ′ configuration which is selectively removable in part or in whole, depending on the design, from nozzle 22 ′ for periodic inspection, repair and/or replacement. Also, this sleeve construction permits the nozzle body to expand independently from the insulating layers, by virtue of the separate and self-supporting nature of the heater sleeves. Thus, when thermal expansion occurs in the nozzle, nozzle body 68 is free to grow longitudinally while the insulating sleeves and wire, which typically have lower thermal expansion characteristics, will not be subject to a mechanical stress induced by this nozzle body expansion. This feature has beneficial implications for increased heater durability.
[0058] The self-supporting annular sleeves of this embodiment may be made of any suitable dielectric material, as described above, that can be machined, molded or extruded into a thin-walled tube. As with the previous embodiments, it is desirable that the coefficient of thermal transfer to be higher for inner sleeve than the outer sleeve. Both sleeves are preferably made of the same materials.
[0059] Further, as one skilled in the art will appreciate, the various layers of a particular heater need not all be applied in an identical manner but rather a combination of layer types may be employed. One will further appreciate that the removability benefit of the sleeve embodiment requires that only at least one of the layers be a self-supporting sleeve, to permit it to be slidably removed from the nozzle assembly. For example, if first layer 84 ′ is provided as a self-supporting sleeve, second layer 86 may be applied directly to first layer 84 (and over wire element 80 , as well) by spraying or other coating method, as described further below. Conversely, in a particular application, it may be desirable to spray or otherwise coat a first layer 84 onto the nozzle body, and provide second layer 86 in a sleeve format In such a configuration, wire element 80 ′ may be integrally provided on the interior of the second layer sleeve element, so as to be removable therewith. Other combinations of layer construction are equally possible, as described below.
[0060] Referring to FIG. 10, in an alternate nozzle embodiment, heater assembly 30 ″ is disposed centrally within nozzle 22 ″. Heater 30 ″ has a core 70 ″, first layer 84 ″, wire element 80 ″, second layer 86 ″ and outer layer 88 ″. A removable nozzle tip 74 ″ is provided to permit heater assembly 30 ″ to be removed from nozzle 22 ″ for inspection, repair or replacement, as described above.
[0061] The present invention may be employed in any known injection molding nozzle design. Referring to FIG. 11, a two-part nozzle configuration according to the present invention is shown. A forward nozzle 100 has a heater assembly 102 according to the present invention, as described above, and a rearward nozzle 104 has a heater 106 according to the prior art, such as, for example, as.is described in U.S. Pat. No. 5,051,086 to Gellert, incorporated herein by reference. Heater assembly 102 has a wire element 110 , a first insulating layer 112 and second insulating layer 114 , similar to that described above.
[0062] It will be apparent to one skilled in the art at the present invention can be employed using a straight wire 120 , as shown in FIG. 12 a, as element 80 to be wound spirally around the nozzle body, as described above. Equally, however element 80 may be a coiled wire 122 , as shown in FIG. 12 b, spirally wound around the nozzle. “Coiled” in this application means helical or spring-like in nature, as illustrated in FIG. 12 b. Coiled wire heating elements are well-known in the heating art as allowing for a reduction in heater power for a given operating temperature.
[0063] Similarly, referring to FIG. 13 a, it will be appreciated that the length of element 80 can be effectively doubled by folding over the wire element, and optionally twisted, to create a unitary element 124 . Element 124 , as expected, has twice the length of wire for a given element 80 length, and is twice as thick. Referring to FIG. 13 b, a coiled and doubled element 126 can equally be provided.
[0064] Referring again to FIG. 3, in use wire element 80 is energized by a power source (not shown). As current flows through wire element 80 , resistance to the electrical flow causes the wire to heat, as is well understood in the art. Heat generated by the element is preferably channelled and expelled substantially inwardly, by the presence first insulating layer 84 and second layer 86 , to heat the pressurized melt in central melt bore 76 . First layer 84 and second layer 86 also provide electrical insulation to electrically isolate wire element 80 from the surrounding metal components of the nozzle.
[0065] The uninsulated resistive wire heating element according to the present invention permits a cheaper heater to be obtained while permitting more exacting temperature distribution and control through more precise and flexible positioning of the element. Unlike the prior art, complex machining of the nozzle body and the need for integrally brazing the heating. element to the nozzle body are removed, permitting savings in cost and time in fabricating the nozzle. Likewise, special and complex film printing techniques, materials and machinery are not required. Further, and perhaps most importantly, the present invention permits smaller diameter heated nozzle designs to be more easily achieved and more reliably operated than is possible with the prior art.
[0066] The heated nozzles of the present invention may be fabricated according to the method of the present invention. In a first embodiment of this method, steel nozzle body 68 is provided as the substrate for spraying first layer 84 thereon. First layer 84 may be provided by spraying, “painting” or otherwise coating in a thickness of between 0.1 mm and 0.5 mm. While greater thicknesses are possible, little benefit is attained by providing a thickness greater than 0.5 mm and, since it is generally desirable to minimize nozzle diameter, greater thicknesses are not typically preferred. First layer 84 is provided on outer surface 72 of nozzle body 68 so as to substantially cover, and preferably completely cover, outer surface 72 over the region where wire element 80 is to be located. After layer 84 is dry, wire element 80 is then positioned around first layer 84 , preferably by winding wire element 80 spirally around the exterior of the nozzle. Although any wire pattern is possible, winding is typically preferred because, among other things, it requires the simplest operation in automated production. With wire element 80 around first layer 84 , second layer 86 is then provided so as to substantially cover, and preferably completely cover, wire element 80 and thereby sandwich and encase wire element 80 between first layer 84 and second layer 86 . Second layer 86 is preferably applied by spraying, “painting” or otherwise coating to a thickness of between 0.1 mm and 0.5 mm (for reasons described above), though any other method of applying second layer 86 may be employed, including providing a sleeve as described below. Once second layer 86 is dry, metal outer layer 88 is provided. Metal outer layer 88 may be applied in any known manner, such as by spraying or by shrink-fitting a sleeve, with spraying being preferred in this embodiment to minimize the overall diameter of the nozzle. With the outer layer applied, the assembly is then typically swaged to compact the assembly and bring the overall nozzle diameter to within desired dimensional tolerances.
[0067] This embodiment of the method permits smaller diameter and more durable nozzles to be obtained than is possible with the prior art.
[0068] Further, the method is advantageous over the prior art since no additional heat treating step is required, thereby simplifying manufacture.
[0069] In an alternate embodiment of the method of the present invention, first layer 84 is provided as a pre-fabricated, self-supporting, substantially rigid, annular sleeve component which is telescopically, slidably positioned concentrically over core 70 . The sleeveless element may be cast, machined, molded or extruded into a thin-walled tube, and may be provided in any desired thickness, though thicknesses in the range of 1.5 mm to 2 mm are preferred to optimize thickness and durability of the sleeve component. The inside diameter of the first layer sleeve is preferably as small as possible while still permitting a sliding installation over core 70 , so as to minimize any air space between the two components. The next step is to position wire element 80 around the first layer sleeve and, as one skilled in the art will understand, it is not important whether the wire element is positioned around the first layer sleeve prior or subsequent to the sleeve's installation on the nozzle body. In fact, an advantage of the method of this embodiment is that the wire element can be pre-wired on the first layer sleeve prior to installation, which can offer flexibility and simplification in manufacturing. Once wire element 80 has been provided around the first layer sleeve, second layer 86 is then applied to substantially cover, and preferably completely cover, wire element 80 so as to sandwich and encase wire element 80 between the first layer sleeve and second layer 86 . Second layer 86 may be applied as a sleeve or by spraying, with the sleeve form being preferred in this embodiment. Again, it is not important whether second layer 86 is applied prior or subsequent to the installation of the first layer sleeve on the nozzle body. Second layer 86 , if applied in sleeve format, is sized to fit as closely as possible over wire element 80 on the first layer sleeve to minimize the air space between the first and second layers. A metal outer layer 88 is then applied to the outside of second layer 86 and may be applied by any known means, such as by spraying or by shrink-fitting a sleeve, with shrink-fitting a sleeve being preferred in this embodiment. Again, as will be understood by one skilled in the art, if a second layer sleeve is used, the outer layer may be applied to the second layer sleeve either pre- or post-installation of the second layer sleeve on the first layer sleeve or the nozzle assembly. With the outer layer applied, the assembly is then typically swaged to compact the assembly and bring the overall nozzle diameter to within desired dimensional tolerances. The assembly is then finished as required. Such finishing steps may include providing removable nozzle tip 74 to the nozzle assembly, if necessary in the particular application.
[0070] This embodiment of the method permits a removable heater assembly to be achieved. The first layer sleeve and/or second layer sleeve can be selectively removed from the nozzle body for inspection and/or replacement, if the heater is damaged or worn, without the need to replace the entire nozzle. Further, the independent nature of the sleeve elements permits the order of assembly to be varied as necessary, for example, by allowing the wire element to be provided on the first layer sleeve prior to installation on the nozzle body. Similarly, the second layer may be provided on first sleeve, over the installed wire, prior to installation of the first layer sleeve on the nozzle body. This advantage offers not only flexibility in manufacture but also permits the wire element to be more precisely placed on the first layer sleeve. For example, laying the wire over the sleeve and then spinning the sleeve so as to wind the wire onto the sleeve permits a precisely controlled pitch and pitch variation. A further advantage of the method is that no additional heat treating step is required, thereby simplifying manufacture.
[0071] It will be understood in the previous embodiment that, if desired, wire element 80 can equally be pre-installed in the interior of a second layer sleeve, rather than the outside of first layer sleeve.
[0072] In both of the above embodiments of the method of the present invention, a metal surface layer 98 of copper or other highly thermally conductive metal may be applied with advantage to the nozzle body prior to providing the first insulating layer, as described above with respect to the apparatus. In one aspect, the surface layer is applied by spraying. In another aspect, the surface layer is provided by shrink-fitting a sleeve onto core 70 of nozzle body 68 . As described above, the surface layer promotes thermal transfer between heater 30 and nozzle body 68 .
[0073] While the above description constitutes he preferred embodiment, it will be appreciated that the present invention is susceptible to modification and change without parting from the fair meaning of the proper scope of the accompanying claims.
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The present invention provides an electrically heated nozzle for injection molding which is insulated to prevent conduction of electricity and loss of thermal transmission to the casing, with an electric heater and sensor that are wrapped around substantially the same portion of a melt channel of the nozzle.
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CROSS REFERENCE TO RELATED APPLICATION
This application is a division of copending U.S. application Ser. No. 07/992,349, filed Dec. 17, 1992.
BACKGROUND
There is provided a catalyst comprising nickel supported on a pillared vacancy titanate material There is also provided a method for preparing this catalyst. There is further provided a process for oligomerizing ethylene using this catalyst.
A variety of oligomerization catalysts have been utilized to convert, i.e., oligomerize, ethylene into olefinic products of higher molecular weight, e.g., to dimer, trimer, tetramer or the like. However, the character and relative proportions of the product mixture are greatly dependent upon the particular catalyst employed. One process is that of Bailey et al., U.S. Pat. No. 2,581,228, which employs a supported nickel oxide catalyst. This catalyst composition produces a product mixture consisting of dimeric products as well as olefinic products in the higher molecular weight range, e.g., trimer and tetramer products.
The oligomerization of ethylene over a supported nickel oxide catalyst is also described in U.S. Pat. No. 3,527,839, the entire disclosure of which is expressly incorporated herein by reference.
SUMMARY
There is provided a catalyst comprising nickel supported on a pillared layered vacancy titanate material, wherein each layer of said layered vacancy titanate material has the formula
[□.sub.y Ti.sub.2-y o.sub.4 ].sup.q-.sub.-
where □ represents a vacancy site, 0<y<2 and q =4y.
There is also provided a method for preparing a catalyst comprising nickel supported on a pillared layered vacancy titanate material, wherein each layer of said layered vacancy titanate material has the formula
[□.sub.y Ti.sub.2-y O.sub.4 ].sup.q-
where □ represents a vacancy site, 0<y<2 and q =4y, said method comprising the steps of:
(a) contacting a pillared layered vacancy titanate material with a solution of a nickel compound under conditions sufficient to sorb at least a portion of said nickel compound into porous regions of the pillared layered vacancy titanate material;
(b) drying the contacted material of step (a) under conditions sufficient to leave a residue of said nickel compound in porous regions of the pillared layered vacancy titanate material; and
(c) calcining the dried material of step (b) under conditions sufficient to convert said residue into nickel oxide.
There is also provided a process for oligomerizing ethylene said process comprising contacting ethylene with a catalyst under sufficient oligomerization conditions, wherein said catalyst comprises nickel supported on a pillared layered vacancy titanate material, wherein each layer of said layered vacancy titanate material has the formula
[□.sub.y Ti.sub.2-y O.sub.4 ].sup.q-
where □ represents a vacancy site, 0<y<2 and q =4y.
DESCRIPTION
A catalyst of nickel supported on a pillared vacancy titanate material (VTM) can oligomerize ethylene to give liquid product efficiently. The liquid product can be used as starting material for chemical synthesis, gasoline or distillate fuel. The new catalyst is much more active than other supported Ni catalysts and produces liquid of higher molecular weight.
The catalyst has unexpected high activity for ethylene oligomerization, and the liquid product has high molecular weight. This high activity catalyst may be used to convert ethylene of low concentration and low value in FCC off-gas into valuable liquid products.
In general, the oligomers produced may have from 4 to 20 carbon atoms.
The oligomerization reaction may be conducted at reaction temperatures varying from about 50° C. to about 250° C., but preferably from about 100° C. to about 200° C. The reaction may be conducted at or above atmospheric pressure. Typical pressures vary from about 1 atmosphere to about 80 atmospheres with the range from about 2 atmospheres to about 35 atmospheres being preferred.
Pillared layered materials which can be used as catalyst supports in the present process are described in U.S. Pat. No. 5,128,303, the entire disclosure of which is expressly incorporated herein by reference.
The layered materials described in U.S. Pat. No. 5,128,303 comprise a layered metal oxide, wherein each layer of the metal oxide has the general formula
[M.sub.x □.sub.y Z.sub.2-(x+y) 0.sub.4 ].sup.q-
wherein M is at least one metal of valence n wherein n is an integer between 0 and 7 and preferably is 2 or 3, □ represents a vacancy site, Z is a tetravalent metal, preferably titanium, and wherein
q=4y-x(n-4) and preferably is 0.6-0.9, 0<x+y<2
The layered materials, which are used to prepare catalyst supports in accordance with the present disclosure, correspond the materials of the above formula, wherein x is zero and Z is Ti. Such materials are referred to herein as vacancy titanates.
It is to be appreciated that the term "layered" metal oxide is used herein in its commonly accepted sense to refer to a material which comprises a plurality of separate metal oxide layers which are capable of being physically displaced away from one another such that the spacing between adjacent layers is increased. Such displacement can be measured by X-ray diffraction techniques and/or by density measurements.
The present layered material may be made from a vacancy titanate starting material which contains anionic sites having interspathic cations associated therewith. Such interspathic cations may include hydrogen ion, hydronium ion and alkali metal cation.
More specifically, the present invention employs a layered metal oxide starting material in which each layer has the general formula
[□.sub.y Ti.sub.2-y 0.sub.4 ].sup.q-
where □ represents a vacancy site, 0<y<2 and q=4y.
Interposed between the layers of the oxide will be charge-balancing cations A of charge m wherein m is an integer between 1 and 3, preferably 1. Preferably A is a large alkali metal cation selected from the group consisting of Cs, Rb and K. Structurally, these metal oxides consist of layers of (□ y Ti 1-y )0 6 octahedra which are trans edge-shared in one dimension and cis edge-shared in the second dimension forming double octahedral layers which are separated by the A cations in the third dimension. These materials can be prepared by high temperature fusion of a mixture of 1) alkali metal carbonate or nitrate and 2) titanium dioxide. Such fusion can be carried out in air in ceramic crucibles at temperatures ranging between 600 to 1100° C. after the reagents have been ground to an homogeneous mixture. The resulting product is ground to 20 to 250 mesh, preferably about 100 mesh, prior to the organic swelling and intercalcation steps.
Further description of various titanometallate-type layered materials and their methods of preparation can be found in the following references:
Reid, A. F., W. G. Mumme, and A. D. Wadsley, Acta Cryst. B24, 1228 (1968); Groult, D., C. Mercy, and B. J. Raveau, J. Solid State Chem. 32, 289 (1980); England, W. A., J. E. Burkett, J. B. Goodenough, and P. J. Wiseman, J. Solid State Chem. 49, 300 (1983). The infinite trans-edge shared layer structure of the vacancy titanates instead of the sheared 3-block structure of, for example, Na 2 Ti 3 0 7 , or the sheared 4-block structure of, for example, K 2 Ti 4 0 9 , may reduce or eliminate shearing of the layers as a possible mechanism for thermal or hydrothermal decomposition of the calcined intercalated material. 15
The layered metal oxide starting material may be initially treated with a "propping" agent comprising a source of organic cation, such as organoammonium cation, in order to effect an exchange of the interspathic cations resulting in the layers of the starting material being propped apart. Suitable organoammonium cations include such as n-dodecylammonium, n-octylammonium, n-heptylammonium, n-hexylammonium, n-butylammonium and n-propylammonium. During this propping or swelling step it is important to maintain a low hydrogen ion concentration to prevent decomposition of the vacancy titanate structure as well as to prevent preferential sorption of hydrogen ion over the propping agent. A pH range of 6 to 10, preferably 7 to 8.5 is generally employed during treatment with the propping agent.
The foregoing treatment results in the formation of a layered metal oxide of enhanced interlayer separation depending upon the size of the organic cation introduced. In one embodiment, a series of organic cation exchanges can be carried out. For example, an organic cation may be exchanged with an organic cation of greater size, thus increasing the interlayer separation in a step-wise fashion.
Interspathic oxide pillars, which may be formed between the layers of the propped or swollen oxide material, may include an oxide, preferably a polymeric oxide, of zirconium or titanium or more preferably of an element selected from Group IVB of the Periodic Table (Fischer Scientific Company Cat. No. 5-702-10, 1978), other than carbon, i.e., silicon, germanium, tin, and lead. Other suitable oxides include those of Group VA, e.g., V, Nb, and Ta; those of Group IIA, e.g., Mg; or those of Group IIIB e.g., B. Most preferably, the pillars include polymeric silica. In addition, the oxide pillars may include an element which provides catalytically active acid sites in the pillars, preferably aluminum.
The oxide pillars are formed from a precursor material which may be introduced between the layers of the organic "propped" species as an ionic or electrically neutral compound of the desired elements, e.g., those of Group IVB. The precursor material may be an organometallic compound which is a liquid under ambient conditions. In particular, hydrolyzable compounds e.g., alkoxides, of the desired elements of the pillars may be utilized as the precursors. Suitable polymeric silica precursor materials include tetraalkylsilicates, e.g., tetrapropylorthosilicate, tetramethylorthosilicate, and, most preferably, tetraethylorthosilicate. Suitable polymeric silica precursor materials also include quaternary ammonium silicates, e.g., tetramethylammonium silicate (i.e., TMA silicate). Where the pillars also include polymeric alumina, a hydrolyzable aluminum compound can be contacted with the organic "propped" species before, after, or simultaneously with the contacting of the propped layered oxide with the silicon compound. Preferably, the hydrolyzable aluminum compound employed is an aluminum alkoxide, e.g., aluminum isopropoxide. If the pillars are to include titania, a hydrolyzable titanium compound such as titanium alkoxide, e.g., titanium isopropoxide, may be used.
Particular procedures for intercalating layered materials with metal oxide pillars are described in U.S. Pat. Nos. 4,831,005 , 4,831,006: and 4,929,587. The entire disclosures of these patents are expressly incorporated herein by reference. U.S. Pat. No. 4,831,005 describes plural treatments with the pillar precursor. U.S. Pat. No. 4,929,587 describes the use of an inert atmosphere, such a nitrogen, to minimize the formation of extralaminar polymeric oxide during the contact with the pillar precursor. U.S. Pat. No. 4,831,006 describes the use of elevated temperatures during the formation of the pillar precursor.
It is preferred that the organic cation deposited between the layers be capable of being removed from the pillared material without substantial disturbance or removal of the interspathic aluminum. For example, organic cations such as n-octylammonium may be removed by exposure to elevated temperatures, e.g., calcination, in nitrogen or air, or by chemical oxidation.
These pillared layered products, especially when calcined, exhibit high surface area, e.g., greater than 200, 300, 400 or even 600 m 2 /g, and thermal and hydrothermal stability making them highly useful as catalysts or catalytic supports, for hydrocarbon conversion processes.
After calcination to remove the organic propping agent, the final pillared product may contain residual exchangeable cation Such residual cations in the layered material can be ion exchanged by known methods with other cationic species to provide or alter the catalytic activity of the pillared product. Suitable replacement cations include cesium, cerium, cobalt, nickel, copper, zinc, manganese, platinum, lanthanum, aluminum, ammonium, hydronium and mixtures thereof.
The pillared layered material catalyst support described herein is used to support a nickel catalyst component. Such component can be exchanged into the composition, impregnated therein or intimately physically admixed therewith. Such component can be impregnated in, or on, the layered material such as, for example, by treating the layered material with a solution containing a nickel metal-containing ion. Thus, a suitable nickel compound for this purpose includes nickel nitrate.
The layered material may be subjected to thermal treatment, e.g., to decompose organoammonium ions. This thermal treatment is generally performed by heating one of these forms at a temperature of at least about 370° C. for at least 1 minute and generally not longer than 20 hours. While subatmospheric pressure can be employed by the thermal treatment, atmospheric pressure is preferred simply for reasons of convenience.
Prior to its use in organic conversion processes described herein, the catalyst should usually be dehydrated, at least partially. This dehydration can be done by heating the crystals to a temperature in the range of from about 200° C. to about 595° C. in an atmosphere such as air, nitrogen, etc., and at atmospheric, subatmospheric or superatmospheric pressures for between about 30 minutes and to about 48 hours. Dehydration can also be performed at room temperature merely by placing the layered material in a vacuum, but a longer time is required to obtain a sufficient amount of dehydration.
The catalyst can be shaped into a wide variety of particle sizes. Generally speaking, the particles can be in the form of a powder, a granule, or a molded product such as an extrudate having a particle size sufficient to pass through a 2 mesh (Tyler) screen and be retained on a 400 mesh (Tyler) screen. In cases where the catalyst is molded, such as by extrusion, the catalyst can be extruded before drying or partially dried and then extruded.
It may be desired to incorporate the catalyst with another material which is resistant to the temperatures and other conditions employed in the catalytic processes described herein. Such materials include active and inactive materials and synthetic or naturally occurring zeolites as well as inorganic materials such as clays, silica and/or metal oxides such as alumina. The latter may be either naturally occurring or in the form of gelatinous precipitates or gels including mixtures of silica and metal oxides. Use of a material in conjunction with the present catalyst, i.e., combined therewith or present during its synthesis, which itself is catalytically active may change the conversion and/or selectivity of the catalyst. Inactive materials suitably serve as diluents to control the amount of conversion so that products can be obtained economically and orderly without employing other means for controlling the rate o reaction. These materials may be incorporated into naturally occurring clays, e.g., bentonite and kaolin, to improve the crus strength of the catalyst under commercial operating conditions. Said materials, i.e., clays, oxides, etc., function as binders for the catalyst. It is desirable to provide a catalyst having good crush strength because in commercial use, it is desirable to prevent the catalyst from breaking down into powder-like materials. These clay binders have been employed normally only for the purpose of improving the crush strength of the catalyst.
Naturally occurring clays which can be composited with the catalyst include the montmorillonite and kaolin family, which families include the subbentonites, and the kaolins commonly known as Dixie, McNamee, Georgia and Florida clays or others in which the main mineral constituent is halloysite, kaolinite, dickite, nacrite, or anauxite. Such clays can be used in the ra state as originally mined or initially subjected to calcination, acid treatment or chemical modification. Binders useful for compositing with the catalyst- also include inorganic oxides, notably alumina.
In addition to the foregoing materials, the catalyst can be composited with a porous matrix material such as silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania as well as ternary compositions such as silica-alumina-thoria, silica alumina-zirconia, silica-alumina-magnesia and silica-magnesia-zirconia.
The relative proportions of finely divided layered catalyst and inorganic oxide matrix vary widely, with the catalyst content ranging from about 1 to about 90 percent by weight and more usually, particularly when the composite is prepared in the form of beads, in the range of about 2 to about 80 weight of the composite.
In the Examples which follow, whenever sorption data are set forth for comparison of sorptive capacities for water, cyclohexane and/or n-hexane, they were equilibrium adsorption values determined as follows:
A weighted sample of the calcined adsorbent was contacted with the desired pure adsorbate vapor in an adsorption chamber, evacuated to less than 1 mm and contacted with 21 Torr of water vapor and 40 Torr of n-hexane or cyclohexane vapor, pressures less than the vapor-liquid equilibrium pressure of the respective adsorbate at 90° C. The pressure was kept constant (within about ±0.5 mm) by addition of adsorbate vapor controlled by a manostat during the adsorption period, which did not exceed about 8 hours As adsorbate was adsorbed by the layered material, the decrease in pressure caused the manostat to open a valve which admitted more adsorbate vapor to the chamber to restore the above control pressures. Sorption was complete- when the pressure change was not sufficient to activate the manostat. The increase in weight was calculated as the adsorption capacity of the sample in g/100 of calcined adsorbant.
EXAMPLE 1
Catalyst Preparation
A silica pillared vacancy titanate material was prepared as follows: 700 g (2.15 mole) CsCO 3 and 895.08 g (11.20 mole) of TiO 2 were ground together to homogeneity and fired at 650° C. for 10 hours. The sample was ball-milled for 4 hours at 30% solids, filtered and air dried. The ball-milled sample was exchanged with ammonium nitrate by stirring in a 1M solution (4000 cc NH 4 NO 3 /1500 g solid) at reflux for 6 hours. After 6 hours, the supernatant was decanted, and the exchange was repeated twice. Cs content was reduced to 1.6 wt.%.
Swelling of the solid was effected by treating the ammonium-exchanged solid in neat octylamine (3500 ml octylamine/1206 g solid) at reflux utilizing a Dean-Start trap i the condensation column. After 4 days, half the sample was removed. An additional 2000 ml octylamine was added to the flask, and reflux continued for an additional 2 days. The solid was then cooled, filtered, washed with 1000 ml ethanol, and air dried. The remaining solid was treated similarly, then blended. The solid was then treated with tetraethylorthosilicate (5 g TEOS/g solid) at 80° C. for 20 hours. An N 2 flow over the reactio prevented adventitious hydrolysis of TEOS by atmospheric moisture. The sample was filtered and dried in air. This sampl was then dispersed in water and stirred for 4 hours at room temperature, followed by filtration and drying in air. The TEOS/H 2 O treatment was repeated twice.
The porous product was obtained by calcining in flowing air The sample obtained had the following properties:
______________________________________SiO.sub.2 67.8 wt. %Ti 15.0 wt. %Cs 0.55 wt. %C <0.1 wt. %N <0.03 wt. %Ash 84.13 wt. %Surface area 390 m.sup.2 /gAdsorption properties (g/100 g)H.sub.2 O 14.5c-C.sub.6 9.7n-C.sub.6 7.3______________________________________
This silica pillared vacancy titanate material was used as catalyst support along 2 other supports made of silica gel (Davisil grade, 635, 60-100 mesh, surface area 480 m 2 /g, pore volume 0.75 cc/g, available from Aldrich Chemical Co.) and alumina (160 m 2 /g, available from Alpha Chemical Co.). These 3 supports were impregnated with a nickel nitrate solution. More particularly, a nickel nitrate stock solution was prepared by dissolving 72.75 g Ni(NO 3 ) 2 6H 2 O in 500 cc distilled water. Each of the 3, above-mentioned solid supports, 50 g each, in powder form, was mixed with 100 cc of the stock nickel solution and stirred for half an hour at room temperature. The liquid was then filtered. The dry catalysts were first calcined at 200° C. under nitrogen for 16 hours and then further calcined with air a 500° C. for 16 hours.
EXAMPLE 2
Ethylene Oligomerization
Each of the catalysts prepared in accordance with Example 1 was used to oligomerize ethylene by the same reaction.
The oligomerization reaction was carried out in a 1 liter autoclave. The autoclave, containing 15 g catalyst, was purged with nitrogen for 16 hours at 150° C. Then 150 cc dodecane solvent was added. When the reaction temperature was stabilized at 150° C., 350 g of ethylene was charged into the reactor in 4.0 hours. Reactor pressure reached 500 psi and dropped quickly to 160 psi in 3 hours. The product was analyzed by gc. The result are summarized in Table 1 Table 1 also includes literature information about ethylene oligomerization over other supported catalysts as reported in U.S. Pat. Nos. 4,942,021 (Ni/ZSM-5) and 3,527,839 (Ni/SiO 2 -Al 2 O 3 ). The nickel on alumina and nickel on silica gel catalysts prepared in Example 1 showed very low activity for ethylene conversion. The product contained mostly butenes.
TABLE 1______________________________________Reaction Conditions and Product Compositions of EthyleneOligomerization by Different Supported Ni Catalysts Ni/ Ni/ZSM-5 SiO.sub.2 --Al.sub.2 O.sub.3Catalyst type Ni/VTM U.S. Pat. No. U.S. Pat. No.Source this work 4,942,021 3,527,839______________________________________Reaction ConditionsTemperature, °C. 150 121 150Pressures, psig 160-400 400 400Catalyst productivity, 3.2 0.5 3.2g of oligomers/gof catalyst/hourAverage product 112 78 60molecular weightProductcomposition, wt. %C.sub.4 13.2 40.8 85.4C.sub.6 20.7 9.6C.sub.8 16.7 40.9 2.3C.sub.10 14.9 1.1C.sub.12 9.1 0.6C.sub.14 6.0 13.5 0.5C.sub.16 1.8 0.3C.sub.16 + 17.7 1.7 0.2Others 0 3.4 0Comments linear or iso-olefins linear,α- iso-olefins olefins______________________________________
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There is provided a catalyst comprising nickel supported on a pillared (e.g., silica pillared) vacancy titanate material. There is also provided a method for preparing this catalyst. This method may involve impregnating a pillared vacancy titanate material with a nickel nitrate solution. There is further provided a process for oligomerizing ethylene using this catalyst.
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This is a Continuation-in-part of Ser. No. 09/212,713, filed on Dec. 16, 1998 U.S. Pat. No. 6,077,156.
BACKGROUND OF THE INVENTION
The present invention relates to grinding systems, particularly those intended for use with angle grinders. Typical grinding discs comprise a substrate or backing material upon which is deposited a maker coat which is used to adhere a coating of abrasive particles applied to the maker coat before it is cured. A size coat is conventionally applied over the abrasive particles to ensure that they are firmly anchored. A supersize coat may be applied over the size coat to confer added properties such as anti-loading, lubrication, grinding aids and the like. More recently other grinding surfaces have been provided in which the abrasive particles are dispersed within a binder which is then deposited on the substrate such that the abrasive material is made in a single step. This binder/abrasive layer may be deposited in a continuous layer that may be smooth or engineered to have a profiled surface with spaced abrading points. Alternatively it may be deposited in isolated islands leaving a profiled surface which also provides spaced abrading points. Such profiled surfaces are very suitable for fine finishing and polishing especially when the particle are small, such as below about 150 microns in average particle size. Such grinding discs are supported on a backup pad which, together with the disc, forms the grinding system as the term is used in this invention.
The drawback of the traditional round abrading disc is that it is not possible to see the surface that is being ground such that it is necessary to grind and then remove to view the surface before grinding again and removing again to view the results. In addition the typical grinding process using conventional discs uses the disc with an attack angle to the workpiece surface of about 45 degrees. This results in gouging unless the operator is quite skilled. These problems were overcome in the invention described in PCT/US96/19191. The abrasive discs described in this Application comprise circular discs having portions removed from at least three spaced positions around the circumference of the disc and holes through the body of the disc, such that the combination of peripheral gaps and holes allow essentially complete view of the portion of the workpiece being ground as it is being ground. In addition to the increased vision and therefore control of the operation, the disc is designed to be used at a very much lower attack angle of about 15 degrees such that a much higher percentage of the actual disc surface is used. By contrast when operating at the traditional high angle of attack the disc has to be discarded after only the outer half inch or so of the periphery of the disc has been worn out. This translates to a much longer life for the disc along with cooler cutting. Such discs are designed to be carried on a backup pad with similar outline shapes. These are described in PCT/US96/18927.
The portions removed from the disc circumference according to the above specification are not restricted to straight chord segments but could include portions that leave the outer perimeter of the disc with a curved outline. The present invention relates to a particularly preferred outline that confers specific advantages especially when working on a surface that meets a second surface angled upward with respect to the surface being ground. In such situations it is possible for the edge of the disc to snag against the angled surface and perhaps tear the disc. The present invention represents a preferred solution to this situation that significantly reduces the consequences of a contact with such an angled surface.
GENERAL DESCRIPTION OF THE INVENTION
The present invention provides an abrasive system comprising a backup pad and, supported thereon in face to face relationship, a fiber-backed abrasive disc, wherein the backup pad has a maximum radius that is from 95 to 100% of the maximum radius of the abrasive disc and from the circumference of which, at spaced intervals, from three to six segments have been removed such that, in the area of the removed segments, the abrasive disc overlaps the backup pad by an amount that is from 10 to 20% of the maximum radius of the abrasive disc. The importance of this feature is that when the abrasive disc is in use abrading a substrate, swarf is produced. Some of this swarf can be expelled through viewing holes where these are provided, but most is generated with a considerable centrifugal component to its motion making ejection to the side favored. Each area of overlap is a point at which the disc is not held in place by the backup pad and is therefore permitted to flex and provide a route by which the swarf can escape. Providing spaced areas of overlap enables the non-overlapping portion to abrade at full force and intervals of lower force grinding allowing the surface and the disc to cool. So prolonging the life of the disc. It is this episodic disc flexing and consequent opportunity for swarf removal and interrupted grinding, (and hence a cooling interval), that gives the system its unique effectiveness.
In a preferred form the abrasive disc and the backup pad that comprise the abrading system have viewing apertures through which a workpiece surface can be observed as the grinding proceeds. A "viewing aperture" is therefore understood to mean an aperture through one component of the system that, when the disc is mounted upon the backup pad preparatory to abrading a workpiece, is in register with a similar viewing aperture in the other component of the system.
In a preferred form of the abrasive system according to the invention, the system comprises a fiber-backed abrasive disc and a backup pad wherein:
a) the disc has a generally circular configuration with from 3 to 9 viewing apertures in the body of the disc at spaced locations around at least one circle concentric with the disc and having a radius smaller than the radius of the disc; and
b) the backup pad is circular with a radius that is from 95 to 100% of that of the abrasive disc and has from 3 to 9 viewing apertures and 3 to 6 equally spaced portions removed from the periphery of the backup pad such that the abrasive disc overlaps the backup pad at such portions by up to 20% of the maximum radius of the abrasive disc when the disc and backup pad are aligned with the viewing apertures on both in register.
A circular abrasive disc has some advantages in reducing the possibility that, when abrading a surface of a body with a complex geometry, the edge of this might catch an angled portion and tear. It does however prevent the area viewed through the viewing apertures from extending to the edge of the disc. For this reason it is often preferred that the abrasive disc have, in addition to the viewing apertures, segments removed from spaced portions of the circumference that correspond in location, but not necessarily in geometry, to those removed from the backup pad.
A further preferred form of the invention which addresses this issue provides an abrasive system comprising a fiber-backed abrasive disc and a backup pad, wherein:
a) the disc has a generally circular configuration with a design direction of rotation when in use, and has from three to six equally spaced portions removed from the circumference of the disc, each such portion having leading and trailing edges defined with respect to the design direction of rotation of the disc, and a length defined by the circumferential distance between the points at which the leading and trailing edges meet the circumference, and wherein the deepest radial penetration of the removed portion into the body of the disc occurs adjacent to the leading edge of each removed portion; and
b) the backup pad is a circular disc having an equal number of equally spaced portions removed from the circumference of the backup pad and viewing apertures in the body of the pad, as are present in the abrasive disc, provided that, when the disc and backup pad are aligned with removed spaced portions and viewing apertures in register, the backup pad has a greatest radial dimension that is from 95 to 100% that of the abrasive disc and, within at least some part of each of the points on its circumference where the abrasive disc has spaced removed portions, the disc overlaps the backup pad by a distance that is from 10 to 20% of the disc radius at that point.
For the sake of this invention the term "adjacent to" is intended to convey that the deepest radial penetration into the material of the disc of the portion removed from the periphery of the disc occurs within 20% and more preferably 10%, based on the total circumferential length of the removed portion, of the point at which the leading edge of the removed portion meets the circumference of the disc.
The backup pad is described as having the same number of portions removed from the circumference as are removed from the disc but it is to be understood that these removed portions need not be identical in shape to those removed from the disc itself. They should however be such that, when the disc and the backup pad are aligned with viewing apertures in register, at no point on the circumference of the backup pad is the radius of the pad greater than that of the disc.
Removed portions from the disc or the backup pad can have a generally V-shaped outline, with one leg of the V much longer than the other, but this is preferably modified by rounding the points at which the leading and trailing edges meet the circumference such that the actual edge meet the notional circumference of the disc asymptotically.
The most preferred profile for the removed peripheral portions on an abrasive disc is one in which all angles of the removed portion are rounded such that the circumference presents from three to six "parrot beak" profiles essentially as illustrated in FIG. 1 attached hereto. The elongation of the trailing edge has the effect of making the transition to the full circumference of the disc quite gradual such that there is no corner or angle to catch if the disc should approach and touch a surface set at an angle to the surface being ground. This effect is enhanced even more by rounding even the low angle at which the removed portion approaches the circumference. Even though the chances of snagging at the angle at which the leading edge of the removed portion meets the circumference are quite small, it is advantageous, as indicated above, to round off this angle also and this is a preferred feature of the invention.
As regards the backup pad the preferred form of removed peripheral portion is a simple chord segment such as is illustrated in FIGS. 2 and 3 of the drawings attached hereto. This permits a larger degree of overlap than if the removed portions on the backup pad merely mimicked those on the abrasive disc on a larger scale. In any event since the purpose on the rounded shapes on the disc is to minimize tearing of the disc during use, and since the backup pad is not so susceptible to tearing under these circumstances, there is no advantage in the use of such a complex shape.
The greatest radial depth of the removed portion, (which is intended to indicate the greatest amount of the disc, with respect to its radius at that point, that is removed), preferably represents less than 20% of the greatest radial dimension. More preferably the greatest depth is from 10 to 20% of the greatest radial dimension. With respect to the backup pad such restrictions are not relevant except to the extent they compromise the support required by the disc if it is to perform adequately.
The number of removed portions is from three to six and is preferably from three to five. In general the larger the number, the shallower the preferred depth of penetration into the material of the disc represented by the removed portions. Three removed portions are generally most preferred.
The backup pad and disc are preferably aligned automatically by an aligning means integral with the design of the backup pad and disc. This aligning means can conveniently be provided by use of a non circular mounting aperture located at the centers of both disc and backup pad. Thus, for example, a triangular mounting aperture in both pad and disc and sized to fit on a triangular bushing which in turn is mounted on to the spindle of a rotary grinder can be designed to ensure that the spaced portions removed from the circumferences of backup pad and disc would be appropriately aligned when the disc is mounted on the backup pad. Alternatives to such shaped mounting apertures include a system of pins or bosses cooperating with mounting holes or recesses, and located on opposed surfaces of the backup pad and disc that are in contact when the system is in use.
The use of a clamping mechanism in conjunction with the aligning techniques is a preferred embodiment of the invention but it is understood that the abrasive disc can also be adhered to the backup pad by other conventional techniques including a pressure sensitive adhesive and a "hook and loop" system. This term is used to cover any system in which mechanical engagement of structures on opposed contacting faces holds such faces together in a readily detachable manner. There are many developments from the basic system using hooks engaging with a fleece, (commercialized under the Velcro® name). Where these methods involve mechanical detachable engagement, they are understood to be included within the scope of attachment means that can be used in the practice of this invention. In the case of an adhesive system, one of the contacting surfaces is most preferably treated to adapt it to receive the adhesive, and this is usually accomplished by laminating a film to the backing of the abrasive disc. In the case of a hook and loop system of attachment, each of the contacting surfaces receives one component of the system. In practice this means that both surfaces have to be laminated to a suitable sheet material with the cooperating component on the exposed surface.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The abrasive surface of the disc can be a conventional surface made by successive applications of maker, abrasive particles, size and optionally supersize layers. However it can also have a profiled surface produced by molding, embossing or gravure printing an abrasive/binder composite deposited on a backing material.
The fiber backing can be made from natural or artificial fibers and included fabrics that have been formed into a coherent sheet material by any conventional process such as knitting, weaving or needle-punching a non-woven fiber assembly. Paper backings are also included in the term "fiber-backed" as it is used in this specification. Typically fiber backing materials need to be pretreated to ensure that the binders placed thereon in the construction of the abrasive disc, (primarily the "maker coat"), are not absorbed into the fiber backing as they are applied and the fiber-backed abrasive discs will be assumed to have received this treatment wherever appropriate or advantageous.
The abrasive grain can be any of those conventionally used to make abrasive discs such as fused or sintered alumina, silicon carbide, fused alumina/zirconia and the like. The binder by which the particles are held can be a phenol/formaldehyde such as is commonly used for most abrasive discs or it could be one of the many other thermally curable substitutes that have been proposed such as urea/formaldehyde resins and epoxy resins. Radiation-curable resins such acrylate-based resins as well as epoxy-urethanes and epoxyacrylates can also be used.
In the preferred embodiments of the invention, it is preferred to provide holes or viewing apertures in the body of the disc so as to provide workpiece surface visibility. The holes can have any shape but, for greatest visibility and least disruption of the abrasive surface of the disc, it is preferred that the holes are round in shape. The holes can however be oval or polygonal if desired provide these do not weaken the structure of the disc. The number of these holes is preferably from 3 to 9 and more preferably 3 to 6. The number of holes is largely determined by the size of the disc. Thus in a 4.5 inch diameter disc, three holes are preferred with the centers of the holes lying on a circle drawn from half to two thirds of the distance from the axis to the circumference of the disc. Larger discs can accommodate up to nine viewing apertures and in such event they can be arrange in groups each group having centers on a circle of a different radius, so as to enlarge the effective amount of the working surface that can be viewed during grinding. As indicated above the location of the holes is preferably such as to increase the visibility of the workpiece surface without diminishing the dimensional stability of the disc under conditions of use or the grinding effectiveness to any unacceptable degree. It is preferred therefore that the holes be located between the portions removed from the circumference and at a radial distance from the center of the disc such that the greatest radial distance of each hole from the center is about the same as the shortest radial dimension of the disc as a result of the removal of a portion of the circumference of the disc. It is preferred that the greatest radial dimension of each hole be less that 30% and more preferably less than 20% of the greatest radial dimension of the disc.
The radius of the disc is not an integral part of the invention. However the most practical applications for such discs require radii of from about 8 cm to 25 cm and most preferably from 11 to 18 cm.
The backup pad often has a shape similar to the disc with which it cooperates to provide the system but this need not imply that the shape mimics that of the disc. In fact in a preferred embodiment the disc has the shape illustrated in FIG. 1 but, as shown in FIG. 2, the backup pad has an equal number of spaced portions removed from the circumference that have the form of straight chord segments. The maximum radius of the backup pad and the disc are within about 5% of one another in this preferred embodiment but the radius in the spaced removed portions is up to 20% shorter for the backup pad than for the disc. The effect is to create regions of overlap of disc beyond the backup pad and this greatly minimizes any tendency of the abrasive disc to catch when accidentally contacted with a surface at an angle to the surface being ground because the disc is able to flex at that point. Additionally such flexing facilitates the discharge of swarf at that point.
DRAWINGS
FIG. 1 is an elevation view of a grinding system according to the invention viewing the surface presented to a workpiece when in use. Such a view shows essentially only the disc.
FIG. 2 is an elevation of the opposed surface from that presented in FIG. 1. It shows therefore mainly the backup pad with the disc only in the overlap areas.
FIG. 3 is similar to FIG. 2 except that the abrasive disc is perfectly circular.
The invention is now further described with reference to the Drawings, which show an abrasive disc, 1, with a generally round configuration with three spaced indentations, 2, remaining after removal of portions of the circumference. The indentations have leading edges, 3, and trailing edges, 4, and a point of greatest depth, 6. The leading and trailing edges each meet the circumference in rounded angles, 7 and 8 respectively, and the point of greatest depth is located adjacent the leading edge such that the distance of point 6 from point 7, measured along the original circumference of the disc, is less than 20% of the circumferential distance separating points 7 and 8.
The disc is also provided with round holes, 9, spaced between the locations of the portions removed from the circumference and at a radial distance from the center of the disc that is less than the shortest radial dimension of the disc after removal of the portions from the circumference.
The disc also has an axially located mounting hole, 10, which, as shown, is shaped to correspond to a mounting bush, (not shown). The shape of the hole corresponds to that in the backup pad, 11, which is also basically a circular disc with three spaced portions, 12, removed from the circumference. While these removed portions can mimic the shape of the portions on the disc, in the illustration in the Drawings the removed portions are straight chord segments of the circumference. In the regions of greatest radial dimension, (where no portion of the disc or backup pad has been removed), the disc overlaps the backup pad by up to about 5 to 10% of the radius of the disc at that point.
Modifications to the features shown in the Drawings could clearly be made without departing from the essential spirit of the invention. All these are included in the invention claimed herein.
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The invention describes an abrasive system comprising a fiber-backed abrasive disc and a backup pad in which the backup pad has spaced portions removed from the circumference such that the disc overlaps in the area of the removed portions. This has the effect of inhibiting catching of the disc on obstructions and enabling easy swarf removal during operation.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to non-metal slings and, in particular, to an apparatus for manufacturing non-metal roundslings.
BACKGROUND OF THE INVENTION
[0002] The term “rigging” (sometimes referred to as industrial rigging or field rigging) is the branch of securing heavy loads in order to prepare the load to be lifted, moved or transported. Rigging usually refers to the ropes, wires, slings, and chains used to secure the load and not the cranes, boomlifts, air skates, forklifts, or other powered equipment that provides the actual force/energy to lift the object.
[0003] Wire rope slings made of a plurality of metal strands twisted together and secured by large metal sleeves or collars are common in the industry. Since wire rope slings are made of metal, they do not require any protection that may be afforded by a covering material. During the past thirty years, industrial metal slings have seen improvements in flexibility and strength. However, compared to non-metal or synthetic fiber slings, metal slings are relatively stiff and inflexible.
[0004] Synthetic fiber slings have gained popularity over the last approximately twenty years and are replacing metal slings in many circumstances. Thousands of synthetic slings are being used on a daily basis in a broad variety of heavy load lifting applications which range from ordinary construction (e.g., nuclear power plants, skyscrapers and bridges), plant and equipment operations, to ship building (e.g., oil rigs), and the like.
[0005] An advantage of synthetic slings over metal slings is that they have a very high load-lifting performance strength-to-weight ratio which provides for a lighter, more flexible and even stronger slings than their heavier and bulkier metal counterparts. An important disadvantage is that synthetic slings require extra steps (primarily encasing the lifting core inside a protective cover), in its manufacturing process.
[0006] Synthetic slings are usually comprised of a lifting core made of twisted strands of synthetic fiber and an outer cover that protects the core. The most popular design of synthetic slings is a roundsling in which the lifting core forms a continuous loop and the sling is generally ring-shaped in appearance. The lifting core fibers of such roundslings may be derived from natural materials (e.g., cotton, linen, hemp, etc.), but are preferably made of hemp, linen, etc. synthetic materials, such as polyester, polyethylene, nylon, and the like. The outer covers of synthetic slings are preferably made of synthetic materials and are designed to protect the core fibers from abrasion, cutting by sharp edges, or degradation from exposure to heat, cold, ultraviolet rays, corrosive chemicals or gaseous materials, or other environmental pollutants.
[0007] A popular method of manufacturing of prior art roundslings is to twist a plurality of yarns together to form a single strand; the strand was then rolled into an endless parallel loop that formed the core. In a separate step, the cover would be manufactured as a flat piece; then the lifting core would be laid on the flat material, and the flat piece of cover material would be bent around the endless core; finally, the edges of the cover are sewn together thereby encasing the core. This method of manufacturing roundslings is time consuming and labor intensive thus increasing the costs to manufacture the sling.
[0008] An important advancement in the rigging industry was the invention of multiple-path slings by Dennis St. Germain. (See U.S. Pat. No. 4,850,629, titled Multiple Path Sling Construction). The manufacturing process for a two-core roundsling is more difficult since it requires more time and labor than a single-core roundsling.
[0009] Machines used to manufacture round slings and multiple-path slings are still relatively labor intensive. Accordingly, there is a need in the industry to reduce the amount of labor needed in the manufacturing of synthetic slings.
SUMMARY OF THE INVENTION
[0010] It is a primary object of the present document to disclose an apparatus for manufacturing non-metal slings and, in particular, an apparatus for making multiple-path slings.
[0011] The subject sling-making apparatus may take on a number of embodiments. However, a preferred embodiment is the making of a two-path industrial sling, i.e., a roundsling having exactly two load-bearing cores.
[0012] The apparatus has three primary sections, namely, the yarn feeder assembly, the control assembly and the tail section assembly.
[0013] The yarn feeder assembly includes a yarn table consisting of a relatively flat table-top having a first end and a second end. The second end of the yarn table abuts the control assembly.
[0014] The control assembly includes an electric motor that provides the motive force for the sling-making apparatus, a power button used to turn the sling-making apparatus on and off, and a control circuit used to track the length of yarn used in the manufacturing of the load-bearing core.
[0015] The tail section assembly includes a pair of diametrically opposed rails on which an idler roller assembly rides. The pair of rails abut the side of the control assembly opposite to the side on which the yarn feeder assembly is located. The idler roller assembly is comprised primarily of an idler roller and the mating section for sliding on the rails. The length of the pair of rails depends on the maximum length of sling to which the sling-making apparatus is designed to make. In a preferred embodiment, the length of the rails is forty feet and the idler roller assembly can slide along the rails to make a roundsling up to eighty feet in circumference.
[0016] Once the length of the sling to be manufactured is determined, the idler roller assembly is slid, in a straight line, along the rails to the determined position—this is away from the controller assembly for long slings and towards the controller assembly for short slings. The idler roller may be allowed to spin or it may be locked into place.
[0017] As will be evident to one skilled in the art, and to provide maximum adaptability for its location, the sling-making apparatus may be left-handed or right-handed. When the yarn table is positioned to the left of the control assembly and the tail section assembly is positioned to the right of the control assembly, the sling-making apparatus is considered left-handed; when the yarn table is positioned to the right of the control assembly and the tail section assembly is positioned to the left of the control assembly, the sling-making apparatus is considered right-handed. However, the side on which each assembly is located with respect to the center control assembly does not affect the operation or process of making a sling.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the following description, serve to explain the principles of the invention. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred, it being understood, however, that the invention is not limited to the specific instrumentality or the precise arrangement of elements or process steps disclosed.
[0019] In the drawings:
[0020] FIG. 1A is a top plan view of an apparatus for making slings in accordance with the present invention;
[0021] FIG. 1B is a side view of the apparatus illustrated in FIG. 1A ;
[0022] FIG. 2A is a top plan view of the fiber guide/separator that forms a part of the yarn table assembly;
[0023] FIG. 2B is a side view of the fiber guide/separator shown in FIG. 2A ;
[0024] FIG. 3A is a top plan view of the control assembly and tail section assembly of the subject apparatus;
[0025] FIG. 3B is a side view of the control assembly and tail section assembly of FIG. 3A ;
[0026] FIG. 4A is a side view of the encoder wheel which forms a part of the control; and
[0027] FIG. 4B is a top view of the encoder wheel shown in FIG. 4A .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] In describing a preferred embodiment of the invention, specific terminology will be selected for the sake of clarity. However, the invention is not intended to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.
[0029] Before the invention is disclosed, it is important to remember some terminology used in the rigging industry and to understand the parts of a sling is made. The term “roundsling” is used to refer to a sling having a ring-like or circular shape. A roundsling has two primary sections; namely, a load-bearing core and a tubular cover which protects the load-bearing core. In a single core roundsling, there is one endless load-bearing core. In a roundsling having exactly two load-bearing cores (e.g., TWIN-PATH® brand dual-core slings), the cover has two separate and distinct channels parallel to each other, and two endless load-bearing cores situated within its own respective channel in the cover.
DEFINITIONS
[0030] Abrasion: The mechanical wearing of a surface resulting from frictional contact with materials or objects.
[0031] Breaking Strength: The total force (lb. or kg.) at which the sling fails. The total weight strain which can be applied before failure, which is usually at least five times the rated capacity.
[0032] Core: The load-bearing multiple fibers of synthetic material which when wound into the seamless tubes becomes the load-bearing yarns of the sling.
[0033] Cover: The seamless tubes that contains the cores. Covers may be of polyester, covermax, Aramid, or other suitable material depending on the desired finished characteristics of the product. Preferably, the cover is made of an inner material hearing a high visibility color, and an outer material made of a contrasting color; when the outer cover material is damaged or worn through, the inner cover material becomes visible allowing for a quick inspection means.
[0034] Elongation: The measurement of stretch, expressed as a percentage of the finished length.
[0035] Fitting: A load-bearing metal component which is fitted to the sling. A fitting can be made from steel, aluminum or other material that will sustain the rated capacity of the sling. The fitting must be smooth and large enough to allow the sling to perform without bunching.
[0036] Length: The distance between bearing points of the sling when laid flat and closed. Measurements are taken from the inside points of contact.
[0037] Proof Test: A term designating a tensile test applied to the item for the sole purpose of detecting injurious defects in the material or manufacture.
[0038] Synthetic Fiber: Any of a multiple of man-made materials used to manufacture the cover, the core, and the thread of the non-metal slings.
[0039] Tell-Tails: Core yarns which extend past the tag area of each sling. When the sling is stretched beyond its elastic limit, they shrink and eventually disappear under the tag. If either tell-tail is showing less than ½″, the sling must be removed from service. If the tell-tails show evidence of chemical degradation, the sling must be removed from service. These may be a fiber-optic cable which will help identify core deterioration.
[0040] Thread: The synthetic yarn which is used to sew the slings, covers, tag and also to provide the stitch which separates the individual load covers.
[0041] Multiple-path non-metal slings were unknown approximately twenty-five years ago. Dennis St. Germain, the inventor herein, invented multiple-path slings in the mid-1980's. The multiple-path sling and, in particular, a sling having exactly two load-bearing cores, has been a commercial success. Slings having two load-bearing cores are sold under the TWIN-PATH® brand. The multiple-path sling is described in U.S. Pat. No. 4,850,629, titled MULTIPLE PATH SLING CONSTRUCTION. U.S. Pat. No. 4,850,629, is hereby incorporated by reference as if fully set forth herein.
[0042] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings in which an apparatus for making slings in accordance with the present invention is generally indicated at 10 .
[0043] Referring now to FIGS. 1A and 1B , a yarn feeder assembly 20 , a control assembly 30 and a tail section assembly 40 are shown. The yarn feeder assembly 20 includes a yarn feeder table 22 having a flat table top 11 with a first end 12 and a second end 13 ; the second end is abutted up against and, is preferably attached to, the control assembly 30 . As illustrated in FIG. 1B , the yarn feeder table 22 has one or more legs 14 to support the table top 11 .
[0044] Spaced at regular intervals, the yarn feeder table 22 has a plurality of openings 23 for allowing an individual strand 25 of yarn to pass therethrough. The individual strands of yarn will be twisted together, as will be described herein, to make the load-bearing inner core of the sling. FIG. 1A illustrates an apparatus 10 having exactly eight yarns used to make the inner core; therefore, this particular yarn table has openings 23 A through 23 H. If the machine is set up to manufacture a multiple-path (e.g., a TWIN-PATH® brand dual-core sling), the yarns are twisted together to make each core of the multiple-path sling.
[0045] The individual strands are made in a separate manufacturing step. As an individual strand of yarn is manufactured, it is rolled onto a heavy-weight cardboard tube. Once the desired length of yarn is rolled onto the heavy-weight cardboard tube, the yarns are delivered to customers in a spool or roll 99 . The dernier, weight and materials used to manufacture the yarn are chosen depending on the type and size of sling to be manufactured. However, in order to reduce inventory, to keep storage space at a minimum, and to streamline the manufacturing process, it is preferable to choose one medium-weight synthetic yarn.
[0046] Beneath the yarn feeder table 22 lies a spool table 24 for holding a plurality of spools 99 of yarn. In a preferred embodiment, as illustrated in FIG. 1B , yarn table 22 can hold two rows of four rolls of yarn (for a total of eight rolls), wherein yarn 25 A is unrolled from spool 99 A, yarn 25 B is unrolled from spool 99 B, etc. However, not every sling that will be manufactured will use the maximum number of yarns. For example, slings designed and rated to lift relatively small loads may use less than eight yarns.
[0047] The spool table 24 has a plurality of elongated extensions 26 A, 26 B, 26 C through 26 H (preferably rod-shaped) that extend from the top surface of the spool table towards the underside of the yarn table 22 . (Although extensions 26 E through 26 H cannot be seen from the drawings, each half of the spool table is identical.) A spool of yarn 99 is slid vertically over each of the extensions 26 on the spool table 24 and the spool's weight keeps it on the spool table.
[0048] The number of elongated extensions 26 are ultimately determined by the maximum size of sling to be manufactured on the apparatus 10 . The number of spools of yarn 99 used to manufacture a specific sling depends on the size of the sling to be manufactured at that time. The number of spools of yarn 99 should not exceed the number of elongated extensions on the spool table. Although the disclosure and the drawings illustrate that there are eight spools of yarn that are slid over eight elongated extensions 26 , the spool table can be enlarged to accommodate more elongated extensions 26 and more spools 99 in order to make larger slings. Similarly, apparatus 10 that are designed to make lower-strength slings may not require a yarn table that can accommodate eight yarns.
[0049] The number of spools that can be held by the spool table 24 corresponds to the number of openings 23 A, through 23 H in the yarn table. Once the size of the sling to be manufactured is determined, the number of yarns to be used to form the load-bearing core can be calculated based on the known weight an individual yarn can hold. Although the first time a sling is made, the number of yarns and other factors may be calculated, some of this information may be obtained through trial and error by manufacturing slings made of varying diameters of yarn, destructively testing the sling, and recording the results. Over time, the number of yarns needed to manufacture a specific load-bearing core will become well-known since all of the other measurements are known (e.g., the thickness of the yarn used, etc.) For example, by doing an initial calculation, then through years of experience in making slings, it is known that eight yarns of relatively medium weight synthetic (e.g., Kevlar® of Kevlar® blend) yarn are required to manufacture the load-bearing core of a 20,000 pound sling. This information can be collected and quantified in a chart which can be consulted by the operator immediately before the manufacturing process.
[0050] Referring again to FIGS. 1A and 1B , proximate each yarn opening 23 A through 23 H, is a spring-tensioning device 27 A through 27 H, respectively. The spring-tensioning devices 27 A through 27 H applies proper resistance to its respective yarn to prevent any slack in the yarn during the cover-making step. The spring-tensioning devices each have their own adjustment to increase or decrease the amount of tension applied to its respective yarn. The spring-tensioning devices are well-known in the industry.
[0051] The sling-making apparatus 10 includes an encoder 29 . The location of encoder 29 can be seen in FIGS. 1A , 1 B, 3 A and 3 B. The encoder 29 includes an encoder wheel 98 and its related circuitry that counts the number of revolutions of the encoder wheel.
[0052] Referring now to FIGS. 4A and 4B , an enlarged view of the encoder wheel 98 is shown. The encoder wheel 98 has a central groove 65 of known circumference. The circuitry is preferably stored in control box 31 . One of the yarns (preferably one farthest away from the control assembly) is wrapped at least partially around the encoder wheel 98 . Since the wheel's circumference is known, the length of the yarn used to manufacture the load-bearing core will be easy to compute. As one skilled in the art can appreciate, after reading the present disclosure, the encoder circuitry may be modified to provide a reading in any length measurement (e.g., feet, yards, meters, etc.)
[0053] A counter circuit that is connected to the wheel actually determines how many feet are used. Since the circumference of the wheel is known (2*pi*r—where “r” is the radius of the wheel 98 in feet), the number of rotations of the wheel will convey the number of feet of yarn that has been pulled from a roll 99 to make the inner core(s). The encoder and its associated circuitry are well-known off-the-shelf products.
[0054] Referring again to FIGS. 1A and 1B , the location of a comb or fiber guide 92 proximate the second end 13 of the yarn table 11 is shown. Preferably the fiber guide 92 is positioned at the junction between the yarn table assembly 20 and the control assembly 30 . The fiber guide 92 ensures that the yarns do not prematurely begin twisting and/or become tangled. The fiber guide 92 includes a base section 93 and a plurality of elongated projections 94 (sometimes referred to as “teeth” or “tines”). The base section 93 has a plurality of projection-holding receptacles 95 into which the elongated projections 94 may be inserted. The elongated projections 94 are preferably rod-shaped and are removable and can be re-inserted into different holding recesses to adjust the separation between each individual yarn with respect to adjacent yarns.
[0055] An enlarged view of the base section 93 of the fiber guide 92 is illustrated in FIGS. 2A and 2B . The base 93 may be made of wood or metal and is secured to the yarn table by using bolts 91 . The base 93 preferably has more projection-holding receptacles 95 than there are the elongated projections 96 . Each projection 94 is inserted into a desired receptacle 96 and secured preferably by a friction fit.
[0056] The receptacles 95 do not have to be spaced in a regular pattern but it may be easier to manufacture the base 93 if they are spaced apart in a regular or repeating manner. The operator of the machine 10 may insert one or more teeth 96 into the receptacles. The primary factor for determining the number of teeth 96 to be inserted into receptacles 95 is the size of the sling to be made which will determine the number of yarns that will be used to make the core.
[0057] The fiber guide 92 is designed to keep the yarns separated until the last possible second to ensure a tight twisting of the yarns as it forms the load-bearing core of the sling. In one embodiment, the teeth 96 are shaped like rods and are frictionally-fitted into the receptacles 95 . In another embodiment, one end of each projection 94 can be manufactured with threads, and the receptacles 95 can be manufactured with mating threads so that the projection 94 may be screwed into its respective receptacle. By moving the projection 94 into different receptacles 95 , the separation of the yarns can be controlled and managed, and ultimately the “tightness” of the wrap of yarns that form the load-bearing core can be controlled.
[0058] Referring again to FIGS. 1A and 1B , the control assembly 30 , including a control box 34 housing control circuitry, and control panel 31 are illustrated. As stated previously, the counter circuit for the encoder 29 may also be stored in the control box 34 . A display 35 that is electrically connected to the counter circuit may be mounted on the control panel 31 for conveying to the machine's operator the length of yarn pulled from the spool 99 of yarn and used to manufacture the load-bearing core.
[0059] The control assembly 30 also includes an electric motor 32 that provides the motive force for the apparatus 10 . The electric motor 32 turns a drive roller 38 and is connected by a chain (using sprockets), belt or preferably a worm gear reducer 33 . An on/off switch 39 controls power to the apparatus 10 and, more specifically to the control circuit.
[0060] The encoder 29 along with the encoder wheel 98 are illustrated as being mounted on the yarn table 11 , but may be placed anywhere so that at least one yarn can engage the wheel 98 to turn it, thereby allowing the encoder circuit to determine the length of yarn used to manufacture the load-bearing core. The encoder display 35 conveys to the operator how many feet of yarn was used in manufacturing the load-bearing core.
[0061] Referring now to FIGS. 3A and 3B , the control assembly is mounted on a table 61 supported by one or more legs 62 . The tail section assembly 40 may be mounted on a table or an open frame 47 so that the working area of the yarn table assembly 20 , control assembly 30 and tail section assembly 40 are all relatively in the same working plane. One or more legs 63 support the frame 47 of the tail assembly 40 . The apparatus 10 is designed to be somewhat modular to allow for easy assembly and disassembly.
[0062] The tail-back assembly 40 is positioned after the control assembly 30 . The tail-back assembly 40 includes a pair of rails 41 , 42 on which an idler roller section 44 slides. The rails ensure that the idler roller assembly 44 , and in particular the idler roller 45 , is parallel to the drive roller. This, in turn, ensures that the yarns that form the load-bearing core are properly twisted and slide with the least amount of friction into the cover of the sling.
[0063] The idler roller section 44 is slidably attached to the pair of rails 41 , 42 for moving the idler roller section in a straight line (i.e., horizontal motion) away from or towards the motor-driven roller 38 . The straight-line distance between the idler roller 45 and the driven roller 38 is approximately one-half the size of the sling that is being made. In other words, if it is desired to make a roundsling having a twenty-foot perimeter, the idler roller section is positioned ten feet away from the driven roller.
[0064] The idler roller section 44 includes means for locking down the idler roller section to one or both rails 41 , 42 thereby preventing the idler roller section 44 from sliding along the rails during the manufacture of the sling. The locking means may be one or more bolts that are secured to the idler roller section 44 and which can be tightened so the bolts frictionally engage one or both rails. As the drive roller 38 pulls the yarn into the cover of the roundsling, a certain amount of tension is created on the idler roller section 44 . By locking the idler roller section 44 into place, the load-bearing cores can be manufactured in substantially one continuous step.
[0065] In one embodiment, the operator keeps track of the number of feet as indicated on the encoder display 35 and stops the apparatus 10 using the on/off switch when the requisite length of yarn to form the load-bearing core is drawn from the spools 99 of yarn. The actual length of yarn pulled from the spools 99 and used to form the load-bearing cores is not precise as long as the minimum length that was calculated at the beginning of the process is used. A few extra feet will only strengthen the load-bearing cores.
[0066] In the preferred embodiment, an electronic decoder control circuit may be employed to automatically turn off the apparatus when the minimum length of yarn is pulled from the spool. As in the manual process, the encoder wheel 29 is used to determine the length of yarn pulled from the spool during the manufacturing of the load-bearing core. The counter circuit can be integrated into the control circuitry via the electronic decoder control circuit for turning off the power to the electric motor when a pre-determined number of feet is pulled from the spool. The operator will program the number of feet of yarn to be used to manufacture the load-bearing cores into the control circuitry at the beginning of the manufacturing process. After the operator turns on the machine 10 , the motor will continue to run until the number of feet programmed into the control circuitry is reached as determined by the encoder wheel 29 and signaled to the control circuitry. In this manner, the control circuitry will automatically turn the machine off thereby stopping the motor and the drive roller. Automating this step in the manufacturing process frees the operator to monitor other steps.
[0067] As indicated previously, the encoder and its associated circuitry are off-the-shelf items that can be easily incorporated in the power circuit of the present machine 10 .
[0068] During the manufacturing process, the cover of the sling is placed around the idler roller 45 . As indicated previously, a leader yarn has been threaded through the channel of the sling cover. In a sling having two load-bearing cores, the cover has two channels in parallel relationship; in this embodiment, a leader yarn is threaded through both channels in the cover. Similarly, for slings having more than two load-bearing cores, a leader yarn is thread through each channel of the cover.
[0069] The cover of the sling is cut to allow access to the interior of the cover. The exposed leader yarn has its ends tied together to form an endless loop. The leader yarn is then placed around the drive roller 38 . The idler roller section 44 is then slid away from the control assembly thereby placing tension on the leader yarn. The number of yarns (e.g., eight) that were determined to be needed to form each load-bearing core are then tied to each leader yarn.
[0070] When the machine 10 is turned on, the leader yarns, being in frictional contact with the driver roller 38 , begins to rotate within their respective cover channels. As the leader yarns rotate, they pull a plurality of yarns off of the spools. As the yarns are pulled from their spools, then through comb 92 , and they are drawn eventually through their respective channels in the cover in a circular motion. The plurality of individual yarns begin to twist in a regular manner as they are drawn within the channel of the cover thereby forming the endless-loop load-bearing cores.
[0071] A preferred embodiment is the making of a two-path industrial sling. The process of making a two-path sling using the apparatus that is the subject of this patent application is straight forward once the apparatus has been disclosed.
[0072] In order to streamline the manufacturing process, the covers are manufactured in an independent step. In this manner, hundreds or thousands of covers can be manufactured at a time. Moreover, the covers can be manufactured off-site using conventional manufacturing techniques. The covers are then shipped to the location where the subject sling-making apparatus is located to manufacture the load-bearing core and for final assembly of the sling. The covers are manufactured with a leader line in each channel. Therefore, if a two-core roundsling is to be made, the cover is manufactured having two channels and there are two leader lines placed in the cover-one for each channel.
[0073] The first step in the manufacturing of a sling is to determine the size of sling to be made (including diameter of load-bearing core which depends on the weight to be lifted and the overall length of the sling) and to determine the type of sling to be made. Based on the size (in particular the length), the idler roller assembly 44 is slid along the rails 41 , 42 to the proper position and secured by the lock-down means.
[0074] The next step in manufacturing a sling involves selecting the appropriate cover material as determined by the sling type and/or customer specifications. Generally, the required length of tubing to form the cover is twice the desired length plus five feet.
[0075] In a preferred embodiment, the inner-side of the cover material will be a contrasting color than the outer-side of the cover material to expedite the inspection process.
[0076] All multiple-core slings are fabricated using the same basic instructions. The required tube widths and requirements are determined by trial-and-error or through experience, and may be quantified and placed in a chart for future look-up.
[0077] Next, the operator moves the (non-rotating) tail stock to the appropriate position as determined by the sling length (2× sling length+about five feet) and secures the tail stock using securing clamps or other means provided to secure the tail stock.
[0078] Using a vise grip pliers or other suitable tool, the operator clamps the end of the cover with the long rolled back cuff to the cross bar 83 . The operator then pulls the cover towards the tail stock assembly 40 and loops the cover material around the idler roller 45 .
[0079] The next step in the manufacturing process is to tie the required number of yarns to the leader yarn in the cover. Any excess polyester leader yarn is cut off after tying it to the cover yarns 99 . The core yarn is inserted into this original loop, and secured (e.g., by taping) in place allowing a sufficient tail. This tail will be used to tie the beginning yarn to the end yarn after load-bearing core is made.
[0080] Once the yarns 99 are tied to the leader yarn, the operator hits the on/off switch 39 to start the electric motor 32 thereby turning the drive roller. The sling-making machine 10 is run until the requisite number of loops, or more accurately the requisite length of yarn 99 has been pulled from the spools. The minimum number of feet of yarn that was calculated at the beginning of the manufacturing process must be pulled from the spools for the size and load-bearing capacity of the sling to be made. (The number of loops of the load-bearing core that are formed depends on the distance between the idler roller and the drive roller.) The motor is pulsed on and off until the original loops and tails are positioned at the drive roller and are accessible to the operator. Since the cover does not rotate during the manufacturing process, the opening of the cover remains proximate to the driver roller.
[0081] The operator feeds each of the filler strands through its respective hole in yarn table and through the tension wheels. The operator adjusts the tension wheels to ensure that there is sufficient tension as the drive roller pulls the yarn from its respective spool.
[0082] Although any of the yarns may be used to wrap around the encoder wheel 98 , the yarn from the spool furthest from the drive roller is preferred.
[0083] The operator loops the filler yarns through the bowline knot of each leader string allowing a sufficiently long tail and then tapes them into an interlocking loop.
[0084] The operator then places pins in the fiber guide 92 to separate the strands entering the cover paths.
[0085] In order to ensure that an appropriate amount of tension is applied to the leader strings, the idler roller 45 may have to be readjusted. The leader strings must be snug against the drive roller 38 so that when the drive roller rotates, the leader string is pulled through its respective channel in the cover. For a multiple-path sling, each leader strings requires substantially equal tension.
[0086] The operator ties a (bowline) knot on each leader string at the end of the cuff. While holding the top knotted end of the leader string, the operator loops the bottom end around the drive roller. The operator pulls out any excess slack from each leader string. The operator then pulls the unknotted end until the desired tension is achieved and secures the unknotted end with two half hitches. The operator then cuts off any excess leader string. These steps are repeated for each of the remaining leader strings if all paths are to be run at the same time.
[0087] The operator then turns on the machine 10 by switching the switch 39 from off to on, and carefully feeds the yarn into the channels of the covers.
[0088] When the counter indicates that the appropriate amount of core material has been used to form the load-bearing cores, the control circuitry from the encoder 29 will automatically stop the machine. As a check, the operator may count the number of strands needed to form each of the load-bearing cores.
[0089] The ends of the load-bearing core are tied together. The sling can then be removed from the drive roller 38 and idler roller 44 . It should be noted that some slings are best manufactured locking the idler roller 44 to prevent rotation.
[0090] The cover is sewn over the opening and closed up allowing only the tell-tails to be seen outside the cover, thereby completing the sling.
[0091] Although this invention has been described and illustrated by reference to specific embodiments, it will be apparent to those skilled in the art that various changes, modifications and equivalents may be made which clearly fall within the scope of this invention. The present invention is intended to be protected broadly within the spirit and scope of the appended claims.
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An apparatus for manufacturing industrial slings which is especially adapted for making roundslings. The apparatus can make slings having one load-lifting core or multiple load-lifting cores. The apparatus has three primary sections, namely, a yarn feeder assembly, a control assembly and a tail section assembly. The sling-making apparatus may be left-handed or right-handed.
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