description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
To move lamps which are mainly intended for clinical use, there are several known devices. In one device, rails and a support movable on these rails are buried in the ceiling; lamps are suspended from this support; and the lamps are movable across an opening provided in the ceiling. In this conventional device, however, the opening is left open without being sealed. As time passes, dust collects in said opening and with an air draft in the room or movement of the lamps, the collected dust falls and spreads, thereby destroying the cleanliness of the room.
Recently, a "clean air" system which assures a sterile, dust-free condition by driving out foul air and introducing fresh, clean air through the ceiling has become increasingly adopted for use mainly in surgical operating rooms.
When the conventional illuminating lamp moving device is used in a room equipped with such a "clean air" system, a turbulence develops around the opening in the ceiling due to the clean air stream and in consequence of this turbulence, the diffusion of dust collected in the opening becomes intense and spoils the sterile condition of the room.
Further this lamp is simply hung on the outside through the opening, and is unsightly.
Also, the conventional device in which, say, the slidable contact for ignition of lamps is easily accessible from the outside involves a hazard of electric shock, which is undesirable from a standpoint of safety.
For these reasons, a lamp-moving device in which the ceiling opening is always sealed, no matter how the lamps are moved and no matter in what position the lamps are located, is necessary.
OBJECT OF THE INVENTION
The primary object of the present invention is to provide a lamp-moving device in which the opening is always sealed, regardless of the movement and position of the lamps.
Another object of the present invention is to provide a lamp-moving device which is not bared to the outside through the opening.
Still another object of the present invention is to provide a lamp-moving device which does not spoil the appearance of the room in which it is installed.
Still another object of the present invention is to provide a lamp-moving device which takes up so small an area that it can be readily installed in addition to the existing equipment and which is so simplified in structure that it can be very easily maintained, inspected or repaired.
Still another object of the present invention is to provided a lamp-moving device which is continuously sealed when the lamps are at rest as well as when they are moving.
Still another object of the present invention is to provide a lamp-moving device which needs no particular drive source.
Still another object of the present invention is to provide a lamp-moving device which serves no operation other than the moving of lamps.
BRIEF DESCRIPTION OF THE DRAWINGS
The lamp-moving device according to the present invention will be better understood by reading the following detailed description of the invention with reference to the attached drawings.
FIG. 1 is an oblique view illustrating the lamp-moving device as installed for practical use.
FIG. 2 is a view taken along the section line A--A in FIG. 1.
FIG. 3 is a view taken along the section line B--B in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, the lamp-moving device according to the present invention is to be described. In the drawings, like parts are denoted by like numbers.
In the ceiling of the operating room, rails 2 are secured by means of anchor bolts. The rails 2 are hollow boxes, and on the bottom surfaces 2b of the rails is a rectangular opening 2a in the longitudinal direction.
Inside the rails 2 is held a base 3. At midpoint of the base 3, the upper end of the lamp-suspending arm 6 is attached. The lamp-suspending arm 6 hangs down through the opening 2a and has at the lower end thereof an illuminating lamp (not shown) which is movable in the vertical direction and has a variable angle. Two pairs of wheels 4 and rollers 5 are rotatable at the front and rear of the base, respectively. The wheels 4 are attached to both sides of the base 3 in such a manner that they can travel over the bottom surface 2b on both sides of the opening 2a of the rails 2. When the wheels 4 travel, the base 3 moves within the rails 2. The rollers 5 are horizontally attached to both sides of the base 3 so that they can travel closely against the inside of both sides 2c of the rails 2. Because of these rollers 5, the moving orbit of the base 3 can always be held centrally in a specific position on the rail 2.
The opening 2a covers the movable range of the lamp-suspending arm 6, which moves together with the base 3. A pair of belt support drums 7 are rotatably fitted to both ends 2d of the rails 2, and at least one of these drums 7 is attached over a spring type support arm 8, which adjusts the tightness of a belt 9. The spacing of these drums 7 is set longer than the length of the opening 2a.
The endless loop belt 9 is wider than the opening 2a, and is stretched over the pair of belt-support drums 7. The belt 9 is maintained in a constant tension by the spring-type support arm 8.
The bottom part of the belt 9, which is wider and longer than the opening 2a, is stretched high enough to touch the bottom surface 2b of the rail 2. Therefore, the pair of belt support drums 7 is set at such a position to hold the belt 9 at that height. Accordingly, the bottom part of the belt 9 covers the opening 2a in the bottom surface 2b of the rail 2.
Both sides of the bottom part of the belt 9 contact a pair of belt guides 10 with no gap. Said pair of belt guides 10, which are longer than the opening 2a, are installed opposite to each other above the bottom surface 2b on both sides of the opening 2a. These belt guides 10 set the belt 9 in position so that the belt 9 covers and seals the opening 2a, and the lamp-suspending arm 6 hanging downward from the base 3 penetrates through the belt 9.
As clearly seen from FIG. 3, the belt 9 is attached to the lamp-suspending arm 6 with no gap at the point of its penetration 9a and to the base 3 with no gap at the point of its contact 9b. Thus, the opening 2a of the rail 2 is sealed with the belt 9 and through this belt 9 the lamp-suspending arm 6 hangs down.
In FIG. 1, an air cleaner orifice 11 commonly provided in the ceiling of the operating room is shown.
In FIGS. 2 and 3, a slidable electric contact 12 is provided to supply power to the lamp.
In the lamp-moving device thus constituted, when the lamp is to be moved, a force is applied to the lamp or the lamp-suspending arm 6 in the desired longitudinal direction along the rail 2. This force is usually applied by a man who handles the lamp. The wheels 4 and the rollers 5 support the base 3 for easy movement within the rail 2 in the longitudinal direction, so the base 3 can be moved by a force applied through the lamp or lamp-suspending arm 6. Together with the movement of the base 3, the lamp-suspending arm 6 fixed to the base 3 and the lamp attached to the lamp-suspending arm 6 are moved to a desired position.
Meanwhile, the opening 2a of the rail 2 is totally sealed with the bottom part of the belt 9, and the lamp-suspending arm 6 hangs down through the belt 9.
Since the belt 9 is rotatably held by the pair of support drums 7 and the contact between the lamp-suspending arm 6 and the base 3 is fixed, the belt 9 as stretched over the pair of support drums 7 can move together with the base 3 and the lamp-suspending arm 6.
Thus, whatever the moving positions of the base 3 and the lamp-suspending arm 6 are, the opening 2a is invariably sealed by the bottom part of the belt 9.
The perfectness of this sealing is assured for the following reasons:
(a) The rollers 5 maintain the path of the base 3 at all times in the central portion of the rail 2. Therefore, even when the base 3 moves, the positional relation of the belt 9 to the opening 2a remains unchanged and the belt 9 never deviates from the opening 2a.
(b) The belt 9 is stretched with a constant tention by the spring type support arm 8.
(c) The belt 9 is positioned with both sides in gapless contact with the belt guides 10.
Power for illumination is supplied to the lamp through an electric contact 12.
It should be understood that the present invention is not confined to the illustrated embodiment, and that various other embodiments are possible without departing from the substance of the present invention.
According to the present invention, the opening, which is invariably sealed, cannot collect dust; and even if dust collects therein, it will not fall in the room. As a result, since there is no possibility that the air stream will disturb the dust, the room can be kept very clean.
Since the installation within the opening is not exposed, there is no hazard of electric shock, thereby enhancing the safety and the appearance.
The opening is sealed with the belt, and the belt is movable together with the lamp. Accordingly, the opening is always sealed in the same state and the sealing of the opening requires no special handling.
The belt itself works within the rails conventionally provided to move the illuminating equipment. Thus, with no major modification, the belt can be readily added to the existing installation.
In the case of a pair of belt-support drums which are rotatably fitted both ends of the rails and endless loop belt being stretched over these drums, the belt is movable by a slight force and no particular drive source is required.
Moreover, the structure is so simplified that maintenance, inspection or repair is very easy.
When the base is provided with rollers, the path of the base can always be maintained central to the rails, and when a spring-type support arm is employed, the belt can be stretched to a constant tightness. Finally, when the belt is guided, the belt can be rightly positioned and the belt and the opening can be brought into close contact with each other through the belt guides, whereby the opening can be perfectly sealed with the belt, regardless of the lamp position. Thus, the lamp-moving device according to the present invention is characterized by these various unprecedented features. | The present invention relates to a device for moving lamps used in clinical situations.
The moving device has rails and a support which is movable on these rails. The rails are buried in the ceiling and the lamp is suspended from the support. The lamp is movable across an opening provided in the bottom of the rails. A belt is stretched across the total area of said opening to completely seal the opening; the downward support for the lamp passes through this belt; and the belt is movable together with the movement of the lamp. | 5 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to user adjustable or expandable materials for use in protective apparel or garments. More specifically, a user adjustable or expandable material for use in an adjustable protective garment is disclosed. A garment using such a material will be capable of providing some protection for an individual in a hazardous environment while permitting easy size adjustability. Protective apparel or garments, such as coveralls and gowns, designed to provide barrier protection to a wearer are well known in the art. Such protective garments are used in situations where isolation of a wearer from a particular environment is desirable, or it is desirable to inhibit or retard the passage of hazardous liquids and biological contaminates through the garment to the wearer.
[0002] For example, in the medical and health-care industry, particularly with surgical procedures, a primary concern is isolation of the medical practitioner from patient fluids such as blood, saliva, perspiration, etc. Protective garments rely on the barrier properties of the fabrics used in the garments, and on the construction and design of the garment. Openings or seams in the garments may be unsatisfactory, especially if the seams or openings are located in positions where they may be subjected to stress and/or direct contact with the hazardous substances.
[0003] Originally, surgical gowns were made of linen, the gowns being sterilized prior to use in the operating room. Linen gowns were not capable of preventing “strikethrough” of various liquids encountered during surgical procedures. As a result, the wearer's clothes came into contact with blood and the like, and a path was established for the transmission of bacteria to and from the wearer of the gown. Additionally, linen gowns, due to their high cost, had to be used a number of times, thus necessitating laundering and sterilization between successive uses.
[0004] In an attempt to reduce strike-through of liquids and to eliminate the need for repeated laundering and sterilization, disposable gowns were made from fluid repellent nonwoven fabrics. These gowns reduced liquid strike-through for a limited time. However, due to the generally inextensible nature of these nonwoven fabric constructions typically they tend to have less ability to conform to the body than the previously used linens or knits. In order to accommodate for a range of body shapes and sizes, the gown is designed to be loose fitting especially in the chest region, sleeve length, and gown length. Making the gown loose fitting generally minimizes the possibility that the gown may otherwise be undesirably too tight in some area or areas. However, this creates the very obvious problem that the gown will be too big for some wearers. By making the gown oversize a wearer having body dimensions smaller than the maximum size contemplated by the gown is subject to areas or regions of the gown or sleeve that hang or are caused to hang loosely. This phenomenon is known as “blousing”. Unfortunately blousing often occurs in or at regions which may be undesirable for the intended use of the gown. Such areas often include the chest region, sleeve area, and the overall length of the gown itself.
[0005] Moreover, many health care facilities purchase only the extra large size version of surgical gowns in order to minimize the volume of different inventory they must maintain on site. In order to fit these gowns to an individual who may be smaller than that intended by the gown size, the typical wearer resorts to taping sections of the gown together to minimize blousing, for example, in the sleeve area or chest region as well as cutting portions of the gown away so as to shorten the overall length of the gown or shorten the sleeve length.
[0006] Thus, a need exists for an improvement in materials which may provide some degree of adjustability to an end user that may be incorporated into user worn protective apparel or garments. Such a material would be capable of being easily incorporated into the protective garment and would also be economically cost effective to implement and practice.
SUMMARY OF THE INVENTION
[0007] Objects and advantages of the invention will be set forth in the following description, or may be obvious from the description, or may be learned through practice of the invention.
[0008] The present invention relates to a material that may be found useful in making a unique configuration of a protective garment, particularly a surgical gown, wherein regions of extensible material are selectively provided in the garment to provide for adjustability to accommodate various size wearers. The areas or regions containing extensible materials may be incorporated into the garment by the addition of a dedicated material having characteristics described herein or alternatively may be formed from the substrate material of the garment itself. In any event, the regions of extensibility are typically surrounded by the remaining material of which the garment is made, generally a nonextensible material and, thus, the regions of extensibility may be thought of as “islands” of extensible material strategically located throughout the gown.
[0009] It should be appreciated that, although the present invention has particular usefulness as a material capable of incorporation into a surgical gown, the invention is not limited in scope to surgical gowns or to the medical industry. The material according to the present invention has wide application and can be used in any instance wherein a user adjustable material is desirable in such garments as protective coveralls, gowns, robes, etc. As such, all such uses and garments are contemplated within the scope of the invention.
[0010] The garment, in form according to the invention may be a surgical gown having a conventional body configuration. That is, the garment may have a closed front portion made from a first panel of material and an open back portion defined by back panels that are attached to the first panel of material alongside the seams of the garment. In an alternate embodiment, the garment may have front and back portions formed from a single piece of material. As discussed in greater depth, the style and configuration of the garments of the present invention are not intended to be considered a limiting factor.
[0011] In an embodiment of the invention, a protective garment is provided having a garment body. The garment may be, for example, a surgical gown, a protective coverall, etc. Moreover, in one particular embodiment an expandable garment is provided. The expandable garment may have a garment body with two sleeves attached. The garment body and sleeves may be formed of a nonwoven fabric having a first fabric surface and a second fabric surface which is opposite the first fabric surface. A section of the fabric defines at least one region gathered into a plurality of successive pleats. Each pleat is made of an overlap in the fabric such that a portion of the first fabric surface is disposed adjacent to another portion of the first fabric surface. These two adjacent surfaces are affixed to one another. The entire region is selectively extensible by application of a tensile force to the region which causes the two surfaces to at least partially detach thus enabling the pleat to at least partially unfold.
[0012] In a further embodiment, it may be desirable to place a plurality of such regions upon sections of the garment. Each region may be adapted to be independently lengthened to accommodate different size individuals. For example, the regions may be adapted to affect overall garment length, affect overall sleeve length, and to affect garment width. A releasable adhesive may be disposed upon at least one portion of the first fabric surface for affixing the surfaces together. Additionally, a releasable adhesive may also disposed upon at least one portion of the second fabric surface for affixing adjacent pleats to one another. Such a garment may prove useful as medical apparel, surgical gowns, shirts, and/or coveralls.
[0013] In another embodiment, an extensible material for use in a garment is provided. Such a material may be configured as a fabric having a length, a first surface, and an opposing second surface. The fabric may contain at least one pleat transverse to the length. The pleat may be made by overlapping the fabric such that a first portion of the first surface is disposed adjacent to a second portion of the first surface and the first and second portions are removably affixed to one another until freed by application of a tensile force directed along the fabric length. Adjacent pleats may be removably affixed to one another until freed by application of the tensile force directed along the fabric length. The required tensile force may be applied by a wearer pulling on the material. The adhesive may be applied so that application of the tensile force results in an incremental release of the affixed portions or application of the tensile force may result in a smooth release of the affixed portions.
[0014] Embodiments of the protective garment according to the invention are described below in greater detail with reference to the appended figures.
BRIEF DESCRIPTION OF THE FIGURES
[0015] FIG. 1 illustrates one embodiment of an exemplary section of an extensible material according to the present invention;
[0016] FIG. 2 is an end view of the FIG. 1 embodiment;
[0017] FIGS. 3-6 depict alternative pleat configurations of an extensible material of the present invention;
[0018] FIGS. 7-9 depict pleat embodiments with adhesive means depicted; and
[0019] FIG. 10 depicts a surgical gown incorporating the material of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Reference will now be made in detail to one or more embodiments of the invention, examples of which are graphically illustrated in the drawings. Each example and embodiment are provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment may be utilized with another embodiment to yield still a further embodiment. It is intended that the present invention include these and other modifications and variations.
[0021] FIG. 1 illustrates an exemplary section of an extensible material 10 which may prove useful for incorporation into those garments where adjustability of portions of the garment to accommodate different size wearers is found especially desirable. An exemplary material 10 would have an initial length “L”, a first surface 12 , and a second surface 14 disposed opposite the first surface 12 . A pleat 16 or a series of such pleats 16 would be formed into the material 10 . These pleats and the manner in which they are employed form the predominant means with which the material is extended. Each pleat 16 is created by folding the material 10 over upon itself so that a portion of one surface lies adjacent to another portion of the same surface. For example, the material 10 in this embodiment is overlapped in a direction that lies perpendicular to the length “L” of the material 10 so that for any one pleat, a first portion 18 of surface 12 is superposed with a second portion 20 of surface 12 .
[0022] Looking now to FIG. 2 , a diagram of an exemplary pleat 16 , may be seen. In this configuration, each pleat 16 is formed by creasing or folding the material 10 such that a first crease 22 having a first peak 24 is formed. The peak 24 points in a direction away from the plane originally established by the first surface 12 prior to folding the material 10 . A second crease 26 is formed in the material 10 a desirable distance from the first crease 22 in a similar manner. This second crease 26 forms a second peak 28 , that points in a direction opposite that of the first peak 24 , i.e., second peak 28 points in a direction toward the plane originally established by the first surface 12 prior to folding the material 10 . As such, the crease 26 may also be considered a reverse fold of the first crease 22 . A series of these folds or creases 22 and 26 are alternately repeated in a pattern to form a plurality of pleats 16 until a desirable number of pleats are formed in the material 10 . Such an arrangement may take on the appearance of an accordion-like folding pattern where each pleat 16 may be identified as beginning with a crease 26 and ending with the next consecutive crease 26 . However, it is only a matter of semantics to identify a pleat in this manner, a pleat may also be considered to begin with a crease 22 and end with the next consecutive crease 22 if desired.
[0023] Turning to FIG. 3 , an alternative pleat 16 is depicted. In this embodiment, each pleat 16 is formed by creasing or folding the material 10 so as to create the first crease 22 having the first peak 24 . However, in this embodiment the first peak 24 points generally toward a first end 30 of the material 10 . The second crease 26 is oppositely folded from the first crease 22 in a manner similar to the FIG. 2 embodiment, however, the second peak 28 points in a direction opposite that of the first peak 24 . That is the second peak 28 points toward a second end 32 of the material 10 . A third crease 34 is formed in the material 10 . The third crease has a third peak 36 that again points toward the first end 30 of the material 10 . A fourth crease 38 is also formed in the material 10 . The fourth crease 38 has a fourth peak 40 that points toward the second end 32 of the material 10 . As depicted, creases 22 and 38 have a section 42 of material 10 disposed therebetween, each section 42 begins and ends with peaks 24 and 40 respectively. Looking to successive sections 42 , it can be seen that the peak 24 of the first section 42 is located a distance “D 1 ” from the peak 40 of the next consecutive section 42 of material 10 . In a similar fashion, creases 26 and 34 have a section 44 of material 10 disposed therebetween beginning and ending with peaks 28 and 36 respectively. Looking now to successive sections 44 , it can also be seen that the peak 28 of one section 44 is located a distance “D 2 ” from the peak 36 of the next consecutive section 44 of material 10 . The dimensions D 1 and D 2 are not critical to the invention. These dimensions may be the same or they may differ with respect to each other. Moreover each D 1 dimension may be different from any other D 1 dimension and each D2 dimension may be different from any other D2 dimension.
[0024] In looking to FIG. 4 , it may be seen that D 1 as well as D 2 may reflect a negative value or physically, an overlap of the material 10 . That is, FIG. 4 depicts the dimension D 1 as reflecting the amount of overlap between peak 24 of the first section 42 and peak 40 of the next consecutive section 42 of material 10 . The dimension D 2 in this FIG. continues to be represented as a positive value which corresponds to a separation between peaks 28 and 36 of two consecutive sections 44 . However, it should be understood that the dimension D 2 may also represent a negative value or overlap. Likewise, the dimension D 1 may be a positive value when the dimension D 2 is a negative value. As should also be understood any combination of values between the dimensions D 1 and D 2 are possible. FIG. 4 is provided to depict one exemplary arrangement. Other arrangements are contemplated and one skilled in the art would understand such other arrangements resorting to this description in conjunction with FIGS. 3 and 4 .
[0025] FIG. 5 depicts an alternative configuration similar to the FIG. 2 embodiment. In lieu of the accordion-fold arrangement depicted in FIG. 2 however, FIG. 5 depicts an overlapping of the peaks 24 and 28 similar to that shown in FIG. 4 . FIG. 6 depicts still an alternative pleat 16 . This pleat 16 is similar to that shown in FIG. 4 , however, there is an additional depth made up of additional creases. These are not labeled in the FIG, simply because the FIG. is meant to depict the many configurations of pleat which are available to choose depending upon how complex the manufacturer wishes to make the pleat as well as the length of material the manufacturer wishes to fold into a discrete area. As such, each crease and overlap in the material enables a greater total length of material to be folded into a smaller space. Nonetheless these FIGs. are intended to depict that each pleat 16 no matter its configuration begins with an arbitrarily identified starting crease and terminates at a subsequent crease. The specific crease at which the pleat terminates may be identified by looking to the entire repeat folding pattern in the material. Each repeat folding pattern may be thought of as constituting an individual crease.
[0026] Despite the specific form of the pleat 16 , each pleat is initially secured so as to prevent its being unfolded without first subjecting it to the application of a predetermined tensile force acting thereon. In one embodiment, an adhesive such as that depicted as adhesive 46 in FIG. 7 is applied in strategic locations that serve to retain the pleat structure but will release upon application of a predetermined appropriate amount of force.
[0027] While it is contemplated that the adhesive 46 may be an organic solvent based adhesive or water based adhesive (e.g., latex adhesive) that can be printed, brushed or sprayed onto the pleat substrate, the coating of adhesive 46 may be in the form of a randomly scattered network of hot-melt adhesive taking on the visual characteristics of filaments and/or fibers which are typically produced by conventional hot-melt adhesive spray equipment. The coating of hot-melt adhesive 46 may also be applied in patterns such as, for example, semi-cycloidal patterns. For example, the adhesive 46 may be a hot-melt self adhesive material applied as generally described by U.S. Pat. No. 4,949,668 to Heindel, et al., which is hereby incorporated by reference. The coating of adhesive 46 may also be a coating of any suitable conventional commercially available hot-melt adhesive such as, for example, hot melt adhesives which may contain a blend of thermoplastic polymers (e.g., thermoplastic polyolefins), adhesive resins, and waxes.
[0028] Exemplary hot-melt adhesives which may be used include auto-adhesive 6631-117-1 and auto-adhesive 6631-114-4 available from the National Starch & Chemical Company, Adhesives Division, Bridgewater, N.J. Other adhesives 46 may be, for example, Hot Melt Adhesive H-9140 available from Findley Adhesives, Incorporated, Wauwatosa, Wis. These adhesives 46 may be blended with other materials such as, for example antioxidants, stabilizers, surfactants, flow promoters, particulates and materials added to enhance processability of the composition. Regardless, the adhesive 46 should be selected such that it is sufficiently tacky to retain the pleat structure until the force is applied, yet it should not be so tacky that it will stick to other surfaces, will be subject to transfer to other surfaces, or will readily stick to itself after its initial separation.
[0029] Looking in more detail to FIG. 7 , the pleat structure of FIG. 2 is depicted with the adhesive 46 applied. As can be seen in FIG. 7 , the adhesive 46 may be applied to the entire first surface 12 . Application of the adhesive 46 may be made to only one of the two adjacent portions 18 or 20 , however, application may be made to both portions 18 and 20 as appropriate. Looking next to FIG. 8 , an enlarged view of an exemplary pleat 16 from the pleat structure of FIG. 3 is depicted. In this FIG., the adhesive 46 is shown as being applied to the material 10 upon those surfaces proximate to peaks 24 and/or 40 that are adjacent to and superposed with the section 44 to which they are associated. Looking to FIG. 8 , it should be envisioned that application of a tensile force in the direction of the arrows “FT” or F′ T ″ will result in the failure of an individual region of adhesive 46 . Continued application of force will result in the failure of other individual regions of adhesive 46 . As such, application of force on a material having individual regions of adhesive will create an intermittent or periodic release of individual regions of adhesive, whereas application of force to a region of adhesive that coats an entire surface as shown in FIG. 7 will be smooth and gradual in comparison. Thus far, the adhesive 46 has been described as being applied only to the first surface 12 . However, as depicted in FIG. 9 , the adhesive 46 may also be applied to the second surface 14 . These FIGs. are also intended to show variations upon where and how the adhesive 46 may be applied to the material so as to maintain the pleat structure until such time that sufficient tensile force is applied to the material 10 to unfold the pleat or pleats 16 . Other variations as well as combinations of those discussed above may also be found suitable and therefore are contemplated by this invention as well.
[0030] The present invention thus far has described a material 10 that may be found useful in making a unique configuration of protective garments, particularly surgical gowns 100 such as shown in FIG. 10 , wherein regions 102 of the extensible material 10 are selectively provided in the garment so as to enable adjustability to accommodate various size wearers. These areas or regions 102 may be incorporated into the garment by the addition of a dedicated material having characteristics described above, or alternatively the regions 102 may be formed from the substrate material comprising the gown itself by incorporation of the appropriate folds thereby creating the creases. Selective application of the adhesive to maintain the initial integrity of the pleats may be accomplished in either situation. In any event, these regions 102 of extensibility are typically surrounded by the remaining material from which the garment is made. This material may be a nonextensible material such as a nonwoven substrate. In this case, the regions 102 of extensibility may be thought of as “islands” of extensible material strategically located in an otherwise nonextensible material comprising the gown 100 .
[0031] It should, however, be appreciated that any garment made in accordance with this invention, including the surgical gown 100 depicted, is not limited to any particular type of materials. Conventional materials for forming gowns are well known to those skilled in the art, and any such material may be used for a gown in accordance with the present invention. As such, the gown 100 may be made from a multitude of materials, including nonwoven materials suitable for disposable use. A material particularly well suited for use with the present invention is a three-layer nonwoven polypropylene material known as SMS. “SMS” is an acronym for Spunbond, Meltblown, Spunbond, the process by which the three layers are constructed and then laminated together. See for example U.S. Pat. No. 4,041,203 to Brock et al. One particular advantage is that the SMS material exhibits enhanced fluid barrier characteristics, making it desirable for use in a surgical setting. It should be noted, however, that other nonwovens as well as other materials including wovens, knits, films, foam/film laminates, and combinations thereof may be used in the construction of the present invention. Likewise, there are a number of elastomeric extensible materials used in the art that may serve adequately and would enhance the function of the extensible regions 102 used in the present invention. As such, it should be appreciated that the type of fabric or material used for the gown 100 is not a limiting factor of the invention.
[0032] Additionally, it should be appreciated that, although the present invention has particular usefulness as a material capable of incorporation into a surgical gown, the invention is not limited in scope to surgical gowns or to the medical industry. The material according to the present invention has wide application and can be used in any instance where a user adjustable material is desirable in such garments as protective coveralls, gowns, robes, etc. Consequently, all such uses and garments are contemplated within the scope of the invention. The value of the material may be easily understood by drawing a comparison to the present state of the art with respect to the solution presented herein. Presently a wearer of a disposable garment is provided with a single predetermined size. Custom fitting of such garments is inherently impractical, therefore portions of the garment are often left long or loose to accommodate a larger percentage of wearer body shapes and sizes. Incorporation of the material described herein in certain areas, for example, in the garment arm sleeves, the garment leggings, at the chest and torso region, as well as those regions directed to total garment length provides a wearer with adjustability. The garment would initially appear to be foreshortened, however, by pulling or tugging on the garment at the appropriate region, i.e., providing the necessary tensile force, that region of material is extended by the partial or full unfolding of pleats contained in the region. This results in a lengthening of the garment at the specific region needed for proper fit for the wearer.
[0033] It should be appreciated by those skilled in the art that various modifications and variations can be made to the embodiments of the present invention described and illustrated herein without departing from the scope and spirit of the invention. The invention includes such modifications and variations coming within the meaning and range of equivalency of the appended claims. | A protective garment having an expandable material incorporated therein is provided. The expandable material may be formed of a nonwoven fabric having a first fabric surface and a second fabric surface which is opposite the first fabric surface. A section of the fabric defines at least one region gathered into a plurality of successive pleats. Each pleat is made of an overlap in the fabric such that a portion of the first fabric surface is disposed adjacent to another portion of the first fabric surface. These two adjacent surfaces are affixed to one another. The entire region is selectively extensible by application of a tensile force to the region which causes the two surfaces to at least partially detach thus enabling the pleat to at least partially unfold. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a ultraviolet ray absorbent glass in which a ultraviolet ray absorbent film is formed on a glass surface.
2. Discussion of Background
It is important to interrupt ultraviolet rays entering into rooms or the cabin of automobiles from the viewpoint of not only preventing sunburn to human bodies but also preventing the deterioration of ornaments in the rooms or the cabin of automobiles.
Heretofore, there have been known to use organic compounds such as benzophenone, benzotriazole and so on as absorbing agents. However, such organic compounds have a disadvantage that they are easily deteriorated with the absorption of ultraviolet rays. In view of the disadvantage, several methods have been proposed wherein an inorganic compound such as zinc oxide, titanium oxide, cerium oxide or the like which does not cause deterioration and has a ultraviolet ray absorbing function is used and a film of the inorganic compound is formed on the surface of a substrate glass to thereby form a ultraviolet ray absorbent glass.
However, the above-mentioned method had a disadvantage as follows. When the oxide is used to form a film on an ordinary glass plate, iridescence was apt to occur in the reflection light due to interference of light because there was a large difference between the refractive indices of the substrate glass and the film of the oxide.
In particular, when a thin film (less than 100 nm) is formed on the substrate glass to impart a ultraviolet ray absorbing function, the ultraviolet absorptive power is insufficient although it can minimize the iridescence in the reflection light due to interference of light. On the other hand, a thick film (more than 800 nm) is formed, it has problems in the strength of the films, the transmittance of visible light and productivity although it can eliminate interference color. Accordingly, in many cases, films having a film thickness range which may cause interference color, are formed. Therefore, the problem of iridescence is unavoidable in a case that a ultraviolet ray absorbent glass is manufactured by using these oxides.
Further, in a summer season, heat of sunlight increases temperature in rooms to reduce cooling efficiency. In order to prevent the disadvantages, there has been an important problem to limit the entering of the sunlight into the rooms to improve the cooling efficiency by imparting heat ray reflectivity to glass plates for automobiles, buildings and so on.
Recently, heat ray reflecting glass which is obtained by forming on a glass surface a film formed of material such as a noble metal, a metallic oxide having electric conductivity or a nitride is mainly used. However, such film is insufficient to absorb ultraviolet rays. Further, it absorbs much visible light depending on material used. Accordingly, the heat ray reflecting glass can not be used as glass required to have a high visible light transmittance, for automobiles, buildings and so on.
Further, there has been proposed a technique of forming a transparent ornament on or in a glass plate by coating a material having a refractive index different from the above-mentioned glass plate, whereby a design is added to the glass plate (Japanese Unexamined Patent Publication No. 247539/1991).
Since metallic oxides such as zinc oxide, titanium oxide, cerium oxide or the like which is used for the film for absorbing ultraviolet rays have a higher refractive index than glass, they can be used for a film for forming the transparent ornament. However, the glass plate having the transparent ornament has a portion which does not partially interrupt ultraviolet rays.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a ultraviolet ray absorbent glass which reduces occurrence of iridescence in a ultraviolet ray absorbent film and has an excellent heat ray reflecting function.
The foregoing and other objects of the present invention have been attained by providing a ultraviolet ray absorbent glass which comprises a substrate glass, a ultraviolet ray absorbent film including as the major component at least one selected from the group consisting of zinc oxide, titanium oxide and cerium oxide, and an intermediate film having an intermediate refractive index which is between the refractive indices of the ultraviolet absorbent film and the substrate glass, said intermediate film being located between the ultraviolet absorbent film and the substrate glass, whereby iridescence by the ultraviolet ray absorbent film is reduced, and a heat reflecting function is imparted.
Further, in accordance with the present invention, there is provided a method of preparing a ultraviolet ray absorbent glass which comprises:
applying on a substrate glass a first solution including metallic compounds to form an intermediate film which has an intermediate refractive index which is between the refractive indices of a ultraviolet ray absorbent film and the substrate glass, and
applying on the intermediate film a second solution including metallic compounds to form the ultraviolet ray absorbent film, whereby iridescence by the ultraviolet ray absorbent film is reduced, and a heat reflecting function is imparted.
As the ultraviolet ray absorbent film used for the present invention, a film comprising as the major component at least one selected from the group consisting of zinc oxide, titanium oxide and cerium oxide is used. Specifically, a film comprising ZnO, TiO 2 , CeO 2 , ZnO--TiO 2 , ZnO--CeO 2 , TiO 2 --CeO 2 or ZnO--TiO 2 --CeO 2 may be used. The composition may include another component.
Among the films as above-mentioned, the ultraviolet ray absorbent film of CeO 2 --TiO 2 series is preferable since it has an excellent ultraviolet ray absorbing function, an excellent surface hardness and durability to chemicals. However, the film of the CeO 2 --TiO 2 series has a very high refractive index, so that it may reduce the visible light transmittance due to a high reflectivity. Accordingly, it is preferable to add material such as SiO 2 or the like having a low refractive index so that the refractive index of the film produced is in a range about 1.9-2.1. The reduction of the visible light transmittance can be eliminated while maintaining a high ultraviolet ray absorbing function by reducing the refractive index of the ultraviolet ray absorbent film and by paying attention to the optical characteristic of an intermediate film which is formed below the ultraviolet ray absorbent film. As an example of the formulation (weight percentage) which has an effective ultraviolet ray absorbing function and a high durability while suppressing the refractivity, CeO 2 /TiO 2 SiO 2 =1.0-5.0/1.0/0.5-1.5 can be proposed.
The film thickness of the ultraviolet ray absorbent film of the present invention is in a range from 100 nm to 800 nm in consideration of the ultraviolet ray absorptive power, the transmittance of visible light, the film strength and so on.
It is important in the present invention that the intermediate film has an intermediate refractive index which is between the refractive indices of the ultraviolet ray absorbent film and the substrate glass.
From the viewpoints of reducing the iridescence suppressing, the reflection of visible light, and increasing the reflection in a near infrared ray region, the most preferable intermediate film is to have the refractive index which satisfies a non-reflection condition, i.e. the equation of n m =(n f ×n g ) 1/2 where n f is the refractive index of the ultraviolet ray absorbent film, n g is the refractive index of the substrate glass and n m is the refractive index of the intermediate film. In practical use, the intermediate film may have the refractive index in a range of (n f ×n g ) 1/2 ±10%.
The film thickness of the intermediate film should have an optical film thickness n m d (d is the film thickness) of a λ/4 wavelength with respect to a visible light region (400 nm-700 nm), and the intermediate film should be a transparent film. Such intermediate film is effective to reduce iridescence and improve the heat interruption power. Especially, when the intermediate film have an optical film thickness of λ/4 of a high visual sensitivity region of 450 nm-650 nm, remarkable effects of reducing iridescence and improving heat interruption power can be obtained. In practical use, the intermediate layer may have an optical film thickness in a range of λ/4±10%.
In the intermediate film having the above-mentioned optical film thickness, the amplitude (intensity) of the reflection light (R1) reflecting at the interface between the ultraviolet ray absorbent film and the intermediate film is equal to the amplitude (intensity) of the reflection light (R2) reflecting at the interface between the intermediate film and the substrate glass, with respect to the visible light, and the phase of the two reflection light R1, R2 is inversed so that the two reflection light R1, R2 are attenuated by the synthesis. As a result, there is only a reflection light at the interface between air near the surface and the ultraviolet ray absorbent film, whereby iridescence of the reflection light due to interference of reflections at plural interfaces can be prevented.
The non-reflection condition is so designed as to obtain in the visible light region. In a near infrared region which has a wavelength longer than the visible light, the phase of the reflection light (R1, R2) is the same, whereby the reflection light is amplified by the synthesis, as a result of which the reflectivity in the region becomes high. Accordingly, the reflectivity of light in the near infrared ray region becomes relatively higher than that of the visible light region, and the heat interruption power also becomes high.
Material for forming the intermediate film of the present invention is not limited as far as the material satisfies the above-mentioned optical characteristic, for instance, SiO 2 , GeO 2 , Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , In 2 O 3 , Ta 2 O 5 , ZnO, CeO 2 or the like, or a mixture thereof, e.g. ZrO 2 --SiO 2 or the like, and it can form a transparent film. Further, from the viewpoint of increasing a ultraviolet ray absorbing function, it is preferred to contain in the intermediate film an oxide for absorbing ultraviolet rays such as zinc oxide, titanium oxide, cerium oxide or the like.
Further, materials of two component series such as ZnO--SiO 2 , ZnO--Al 2 O 3 , ZnO--GeO 2 , ZnO--ZrO 2 , TiO 2 --SiO 2 , TiO 2 --Al 2 O 3 --TiO 2 --GeO 2 , TiO 2 --ZrO 2 , CeO 2 --SiO 2 , CeO 2 --Al 2 O 3 , CeO 2 --GeO 2 , CeO 2 --ZrO 2 or materials of a three or more component series wherein at least one component selected from the group consisting of ZnO, TiO 2 and CeO 2 is added to the two-component series material, may be used.
Further, the heat ray reflection power can be increased by incorporating an electric conductive component in the intermediate film. As the electric conductive component, Sb--SnO 2 , Sn--In 2 O 3 or Al--ZnO is exemplified.
In the present invention, when the heat interruption power (the ratio of difference of the solar radiation transmittance and the visible light transmittance of glass) is 1 or higher, heat ray reflecting power is given.
In the present invention, methods of forming the ultraviolet absorbent film and the intermediate film are not particularly limited, but conventional methods which have been used for forming films, dry processes such as a vacuum deposition method, a sputtering method, a CVD method or a wet process such as a sol-gel method, a spray type thermal decomposition method or a coating type thermal decomposition method can be widely used.
In forming a transparent ornament in the glass plate, the patterning of the intermediate film is performed before the formation of the ultraviolet ray absorbent film. In the patterning method, a part of the intermediate film may be removed by etching or the like after the intermediate film has been formed in the glass surface, or a printing method or a masking method may be used to form a portion where a part of the intermediate film is previously omitted.
BRIEF DESCRIPTION OF DRAWING
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 is a schematic view showing a ultraviolet ray absorbent glass having an ornament.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A preferred embodiments of the present invention will be described with reference to the drawing.
In FIG. 1, reference numeral 1 designates a substrate glass, numeral 2 designates an intermediate film for preventing interference color, numeral 3 designates a ultraviolet ray absorbent film, and numeral 4 designates a hollowed portion in the intermediate layer for preventing interference color.
The intermediate film for preventing interference color which has a pattern is formed on the substrate glass by using a conventional method such as a sputtering method or a sol-gel method. Further, the ultraviolet ray absorbent film 3 comprising titanium oxide, cerium oxide and so on as major components is formed on the entire area of the intermediate film 2 by a conventional method so that the film 3 has a predetermined thickness. The interference color can be changed by changing the film thickness of the ultraviolet ray absorbent film. Accordingly, the color of an ornament can be changed depending on a position of a ultraviolet ray absorbent glass to be used and environments.
The ultraviolet ray absorbent glass of the present invention is preferably used for automobiles. In preparing it, a first solution including metallic compounds for forming the intermediate film is applied onto a substrate glass, and a second solution including metallic compounds for forming the ultraviolet ray absorbent film is applied onto the intermediate film.
The second solution applied on the substrate glass may be baked by utilizing heat used for strengthening glass and/or heat used in a shaping process, particularly for automobiles.
The solution applied on the substrate glass by a wet process becomes a strong film by reacting with glass by the application of heat. However, it is preferable that the ultraviolet ray absorbent glass of the present invention is baked by heat which is produced at the final process for strengthening and shaping a window glass for automobiles in which the window glass is heated at a temperature near the glass softening point.
Although it is possible to previously bake the glass before strengthening and shaping, it is advantageous in productivity and manufacturing cost to bake the glass by utilizing heat used for strengthening and/or shaping of the glass.
The solution for forming the intermediate film and the solution for forming the ultraviolet ray absorbent film are not particularly limited as far as they are soluble to solvent. However, metal alkoxide or a metal chelate compound is preferably used in consideration of uniformity in the film after the baking and the hardness of the film surface after the baking.
The solution including the metal alkoxide or the metal chelate may be formulated by a conventional method such as a sol-gel method. Tetraisopropyl titanate (TPT), tetraethylortho silicate (TEOS) and so on are dissolved in an organic solvent such as alcohol, in consideration of the refractive index of each of the oxides and the refractive index of a film obtained by a mixture while the formulation is controlled from Lorenz-Lorenz formula, and if necessary, an aqueous solution such as hydrochloric acid or nitric acid is added to progress hydrolysis and polymerization.
As the method of forming the film, a conventional method such as a wet type coating method can be used. However, a transfer-printing or flexographic printing is more preferably used in consideration of productivity, the yield of the solution for forming the film and uniformity in film thickness.
When the transfer-printing or flexographic printing method is selected, selection of solvent is an important factor from the viewpoint of the rheology characteristic of the solution to be applied. As organic solvent having a suitable rheology characteristic for the solution applied by printing, there are a glycol such as hexylene glycol, diethylene glycol or the like and a glycol ether such as diethylene glycol monoethyl ether or the like.
An upper coat may be applied after the intermediate film has been applied, followed by baking. However, this method uses baking processes twice, and it is disadvantage in saving energy. An advantageous way is that after the solution for the intermediate film has been applied, it is dried by hot air or the irradiation of ultraviolet rays; an upper coat is applied on the dried film, and the two layers are simultaneously baked.
The drying method by irradiating ultraviolet rays is very effective from the aspect of productivity since a drying time is short as several seconds to several tens seconds. When an organic metallic compound such as metal alkoxide or a metal chelate compound is used in that case, the effect obtained by irradiating ultraviolet rays is further increased since many of organic compounds have sensitivity to ultraviolet rays.
As conditions of treatment to dry the intermediate film, although they vary depending on the formulation of the solution and the film thickness, the intermediate film can be dried to an extent of capable of applying the upper coat by heating it at a temperature of 100° C.-150° C. for more than two minutes in a case of using a hot air drying method, or by irradiating ultraviolet rays in an energy level more than about 3 J/cm 2 in a case of irradiating ultraviolet rays. By combining these measures, it is possible to dry the intermediate film with a further shorter time and a lower energy.
Further, a ceramic color paste or an electric conductive silver paste used for a window glass for automobiles can be simultaneously baked when they are in a complex form. In this case, the ceramic color paste or the conductive silver paste may be printed before the baking of the ultraviolet ray absorbent film applied to the glass in a furnace for strengthening. On the contrary, the ultraviolet ray absorbent film may be formed by printing on the substrate glass which has been applied with the ceramic color paste or the conductive silver paste followed by dried, and then, the baking process be conducted. Of course, the ultraviolet ray absorbent film, the ceramic color paste or the conductive silver paste can be separately baked. However, this method is disadvantageous in saving energy as described before.
Several Examples will be described. However, the present invention is not limited to these examples.
Evaluation of films obtained by the following Examples and Comparative Examples was made with respect to appearance (by eyes), ultraviolet ray transmittance (T UV ): IS09050), visible light transmittance (T V : JIS-R3106), solar radiation transmittance (T E : JIS-R3106), heat interruption power (ratio of difference between the solar radiation transmittance and the visible light transmittance to glass, ΔT E /ΔT V ) and chroma (C* : (a* 2 +b* 2 ) 1/2 in CIEL*a*b*).
EXAMPLE 1
22 g of 1-propanol, 7 g of acetylacetone and 30 g of cerium nitrate were mixed and dissolved to form a solution (A solution), and the solution was stirred for a night.
To 58 g of 2-propanol, 26 g of the solution A, 3.6 g of ethyl silicate 40 (silica content: 40%), 8.7 g of titaneacetylacetonate (Ti(OPr) 2 (Acac) 2 ) and 0.6 g of a 0.1N hydrochloric acid aqueous solution were mixed to prepare a coating solution B.
To ethanol, 4.5 g of ethyl silicate 40, 4.3 g of tetraisopropyl titianate and 3.0 g of 0.1N hydrochloric acid aqueous solution were successively added and well mixed to prepare a coating solution C.
On soda lime glass (n g =1.52), the coating solution C was applied by a spin coat method. The coating solution C was baked at 200° C. for 30 minutes to obtain an intermediate film of a TiO 2 --SiO 2 series transparent film (TiO 2 :SiO 2 =40/60) in weight ratio) which had a refractive index of 1.74 and a film thickness of 68 nm. The coating solution B was applied thereon by spin-coating method, and was baked at 600° C. for 5 minutes to form a CeO 2 --TiO 2 --SiO 2 series ultraviolet ray absorbent film (CeO 2 :TiO 2 :SiO 2 =64/18/18 in weight ratio). The ultraviolet ray absorbent film had a refractive index of 2.05 and a film thickness of 180 nm. The optical characteristics measured are shown in Table 1.
EXAMPLE 2
In ethanol, ethyl silicate 40, tetraisopropyl titanate and a 0.2N-hydrochloric acid aqueous solution were successively added and well mixed to prepare a coating solution for forming an intermediate film. The coating solution was coated on the soda lime glass by a spin coat method. The coated solution was baked at 200° C. for 30 minutes to obtain an intermediate film (TiO 2 :SiO 2 =38/62 in weight ratio) composed of a TiO 2 --SiO 2 series transparent film having a refractive index of 1.72 and a film thickness of 75 nm.
On the intermediate film, cerium oxide colloidal sol (manufactured by Taki Kagaku K.K.: tradename: Needral U-15) was coated by the spin coat method. The cerium oxide colloidal sol was baked at 200° C. for 30 minutes to form a ultraviolet ray absorbent film, whereby a ultraviolet ray absorbent glass was obtained. The ultraviolet ray absorbent film had a refractive index of 1.95 and a film thickness of 290 nm. The characteristics of the obtained ultraviolet ray absorbent glass are shown in Table 1.
EXAMPLE 3
Ethyl silicate, cerium nitrate and acetylacetone were successively added to ethanol to prepare a coating solution for an intermediate film. The coating solution was coated on soda lime glass by a spin coat method. The coated solution was baked at 400° C. for 10 minutes to obtain an intermediate film (CeO 2 :SiO 2 =40/60 in weight ratio) composed of a transparent film of CeO 2 --SiO 2 having a refractive index of 1.68 and a film thickness of 68 nm. On the intermediate film, a coating solution in which fine particles of zinc oxide are dispersed (manufactured by Sumitomo Cement Kabushiki Kaisha, tradename: ZC-120M) was coated by the spin coat method. The coated solution was subjected to the same treatment as in Example 1 to form a ultraviolet ray absorbent film whereby a ultraviolet ray absorbent glass was obtained. The obtained zinc oxide film had a refractive index of 1.88 and a film thickness of 520 nm. The characteristics of the obtained ultraviolet ray absorbent glass is shown in Table 1.
EXAMPLE 4
A ultraviolet ray absorbent glass was prepared in the same manner as in Example 1 except that the intermediate film had a refractive index of 1.73 and a film thickness of 70 nm, which was formed by using a coating solution in which fine particles of antimony-containing tin oxide having an average diameter of 10 nm are dispersed so as to have a weight ratio of SiO 2 /TiO 2 /Sb--SnO 2 =30/10/60. The characteristics of the glass obtained are shown in Table 1.
COMPARATIVE EXAMPLE 1
A ultraviolet ray absorbent glass was prepared in the same manner as Example 1 except that the intermediate film was not formed. The characteristics of the glass obtained are shown in Table 1.
TABLE 1______________________________________ Upper coat film Heat thickness T.sub.UV T.sub.V T.sub.E interruption (nm) (%) (%) (%) power C*______________________________________Example 1 180 8 86 79 2.0 1.7Example 2 290 8 86 80 1.8 3.6Example 3 520 2 87 81 2.0 3.4Example 4 180 7 86 76 2.8 1.8Comparative 180 9 82 85 0.3 15.7Example 1Glass -- 70 90 87 -- --______________________________________
EXAMPLE 5
An embodiment of the ornamentation of the present invention is described with reference to FIG. 1. An intermediate film 2 for preventing interference color having a hollowed portion 4 of a pattern desired for an ornament is formed on a surface of a substrate glass 1, and a ultraviolet ray absorbent film 3 is formed on the intermediate film 2. The intermediate film 2 and the ultraviolet ray absorbent film 3 are formed by the method described in Example 1. The patterned hollow portion is formed by etching after the forming of the intermediate film 2.
EXAMPLE 6
A ultraviolet ray absorbent glass was prepared in the same manner as in Example 1 except that the ultraviolet ray absorbent film was baked in a strengthening furnace heated to 700° C., instead of baking it at 600° C.
The obtained ultraviolet ray absorbent glass was transparent and the optical characteristics of the glass were the same as those of the glass in Example 1.
EXAMPLE 7
All the solvent for the solution A, the coating solution B and the coating solution C used in Example 1 were changed to hexylene glycol (which are referred to as solution A', coating solution B' and coating solution C', respectively). The coating solution C' was coated on a substrate glass by flexographic printing, and the coated solution was dried by irradiating ultraviolet rays with use of a metal halide lamp to thereby form an intermediate film. The coating solution B' was coated on the intermediate film by flexographic printing, and coated solution B' was dried at 150° C. for 5 minutes, followed by baking it in a strengthening furnace.
The obtained ultraviolet ray absorbent glass was transparent, and the optical characteristics of the glass were the same as those of the glass obtained in Example 1.
EXAMPLE 8
According to the method of Example 7, solutions for the intermediate film and the ultraviolet ray absorbent film were coated on the glass. After they were dried, a black ceramic color paste and a conductive silver paste were applied with a pattern by screen-printing. The pastes were dried in a drying device of 100° C. for 2 minutes. The obtained product was baked and strengthened in a strengthening furnace.
The obtained ultraviolet ray absorbent glass was transparent, and the optical characteristics were the same as those of the glass obtained in Example 7. Further, there were found no run and no color change of the black ceramic color and the silver electrode. The performance of the obtained glass was the same as that of a conventional glass with printing.
EXAMPLE 9
On a substrate glass, a black ceramic color paste and a conductive silver paste were printed respectively with use of a screen-printing machine, followed by drying them in a drying device of 100° C. for 5 minutes. The coating of the solutions and the baking were conducted in the same manner as those in Example 7.
The obtained glass was transparent, and the optical characteristics were the same as those of the glass obtained in Example 7. Further, there were found no run and no color change of the black ceramic color and the silver electrode. The performance of the glass was the same as that of a conventional glass with printing.
COMPARATIVE EXAMPLE 2
The coating solution B' for a ultraviolet ray absorbent film used in Example 7 was directly formed on a substrate glass by printing, and film forming was made in the same manner as in Example 7.
The obtained film had a refractive index of 2.3 and a film thickness of 180 nm.
The film was transparent. However, the reflection light was green and the reflectance was high whereby the heat interruption power calculated was 0.79.
Thus, in accordance with the present invention, iridescence caused in an oxide film type ultraviolet ray absorbent glass, which was a problem in conventional technique, can be reduced: reflection light can be controlled to an extent near a neutral color, and a heat reflecting function can be imparted without reducing the visible light transmittance. Accordingly, the ultraviolet ray absorbent glass can be widely applied to fields of automobile and building.
Further, the ultraviolet ray absorbent glass of the present invention can be provided with flexibility in a transparent ornament or design without sacrificing a ultraviolet ray absorbing function.
Further, in accordance with the present invention, a ultraviolet ray absorbent glass for automobiles capable of reflecting near infrared rays without reducing the visible light transmittance and having a high heat interruption power can be obtained in a simple method with saving energy.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A ultraviolet ray absorbent glass comprises a substrate glass, a ultraviolet ray absorbent film including as the major component at least one selected from the group consisting of zinc oxide, titanium oxide and cerium oxide, and an intermediate film having an intermediate refractive index which is between the refractive indices of the ultraviolet absorbent film and the substrate glass, the intermediate film being located between the ultraviolet absorbent film and the substrate glass, whereby iridescence by the ultraviolet ray absorbent film is reduced, and a heat reflecting function is imparted. | 2 |
FIELD OF THE INVENTION
This invention relates to improvements to tow-bars and in particular relates to an additional component that can be used with a conventional tow-bar.
BACKGROUND OF THE INVENTION
Many vehicles such as cars and four wheel drives are these days fitted with tow-bars.
Conventional tow-bars comprise a bar that is mounted to the rear of the towing vehicle through a number of mounting points to distribute the towing load. The bar is a sturdy steel construction and is coupled to a towing hitch that includes an upstanding tow-ball that is adapted to fit on a towing socket that is provided on the vehicle that is to be towed. The ball and socket means of attachment is the most common means of attaching a trailer to a tow-bar. However to allow the vehicle to turn relative to the trailer it is important that there is space between the rear of the vehicle and the tow-ball, thus towing hitches have the effect of causing the tow-ball to project rearwardly of the vehicle. This rearward projection of the tow-ball is potentially hazardous both in terms of the damage that it can cause to a vehicle that may make a slow speed collision with the rear of the vehicle and the damage it does to pedestrians' legs as they walk behind the vehicle and do not see the tow-ball which is comparatively close to the ground. Many pedestrians have severely bruised their shins in this manner.
Many towing hitches can be removed from the tow-bar by either removal of a locking pin that holds the hitches in position or unbolting the towing hitch from the bar. The problem with removing the towing hitch is that most tow-bars also include an electrical socket into which a plug from the trailer can be inserted to enable the trailer to display turning, tail and stop lights. If the towing hitch is removed from the tow-bar and a vehicle was to make a slow speed collision with a towing vehicle, the electrical socket, because it often projects rearwardly of the vehicle, takes the full impact of the load and thus is easily damaged.
SUMMARY OF THE INVENTION
It is these issues that have brought about the present invention.
In accordance with the present invention there is provided a protective device for use with a tow-bar having a bar and a towing hitch coupling, the protective device comprising a substantially T-shaped member whereby the leg of the T is to be coupled to the towing hitch coupling, and the head of the T extends rearwardly of the towing vehicle past any rearwardly projecting components of the vehicle.
The T piece preferably comprises a post welded to a metal plate with the plane of the plate perpendicular to the longitudinal axis of the post. The post including means to facilitate attachment to a tow-bar. The post is preferably of square cross-section and is adapted to be a sliding fit within the interior of a coupling bracket welded to the towing bar. Apertures are positioned across the post to accommodate a locking pin that extends through the bracket on the towing bar and through the apertures on the post of the T-shaped member. The head of the T-shaped member may be asymmetrically mounted to the post.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which:
FIG. 1 is a schematic illustration of a conventional prior art tow-bar and towing hitch,
FIG. 2 is a schematic illustration of a towing bar with the towing hitch removed and replaced by a protective device in accordance with one embodiment of the invention,
FIG. 3 is a perspective view of the protective device,
FIGS. 4 a and 4 b show the device in two mounting positions, and
FIGS. 5 a and 5 b show the device at two different heights.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 , the conventional layout of a tow-bar T and towing hitch H is schematically illustrated. This is the prior art assembly that is frequently used on vehicle such as four wheel drive vehicles.
The tow-bar T of such vehicles comprises a sturdy steel bracket assembly (not shown) that is bolted to the chassis of the vehicle V in a number of spaced positions in order to distribute the towing load across the rear of the vehicle. A towing hitch H is attached to the towing bar T via a towing hitch coupling to project rearwardly of the vehicle for attachment to the trailer or the vehicle that is to be towed. The towing hitch coupling is illustrated as bracket B which is usually in the form of an elongate steel tube with a square or rectangular interior. The towing hitch H has a similarly profiled square post P that is a sliding fit within the interior of the bracket B. An aperture A extends through the walls of the bracket B and the towing hitch H and a large pin (not shown) extends through the apertures to hold the assembly together. Various means can be positioned on the end of the locking pin to prevent removal including keyed locks.
The projecting end of the post is then welded to an L-shaped plate L that projects rearwardly and has bolted to it a conventional tow-ball S. The distance between the tow-ball S and the rear of the vehicle V is selected to allow the vehicle to turn relative to the trailer without the trailer fouling the rear of the vehicle V.
Trailers are usually by law required to include a lighting system, namely tail lights, stop lights and turning lights. It is thus usual for trailers to have a plug that can be coupled to a socket E mounted on the rear of the vehicle to effect transfer of the vehicle's lighting to the trailer. The usual position of the electrical socket E is such that if the towing hitch H is removed from the tow-bar T in situations where the vehicle is not used for towing, the most rearwardly projecting component of the vehicle is the electrical socket E which leaves the socket E very vulnerable to damage especially during parking.
The invention as illustrated in FIGS. 2 to 5 essentially comprise a device 10 that can replace the towing hitch H when not required to protect the electrical socket E and other componentry at the rear of the vehicle V. The device 10 is essentially a protector that is adapted to be attached to the tow-bar T in the same manner as the towing hitch H.
Thus, the protector 10 comprises a square shaped post 11 that is adapted to be a sliding fit within the female bracket B that is part of the tow-bar T. If the bracket B of the towing hitch H happens to not be in the form of an elongate square tube, post 11 can be modified in shape to a corresponding construction to the bracket thereby enabling coupling of the protective device 10 and bracket B.
The post 11 has apertures 20 , 21 and 22 extending laterally across the post to accommodate a locking pin (not shown) in exactly the same manner shown in FIG. 1 . The post 11 is welded to a rectangular steel plate 14 and the mounting is such that the plane of the steel plate 14 is rearward of the furthest projection of the vehicle V. Thus, should a vehicle V carrying the protector 10 be involved in small contact during parking or from collision with a vehicle from the rear, the collision would occur first with the plate 14 thereby protecting the potentially vulnerable electrical socket E and rear bumper bar R of the vehicle and minimising damage to the front of the rear vehicle.
The size of the plate 14 is sufficient to take small impact loads and although a planar rectangular plate is illustrated in FIG. 2 it is understood that other profiles are envisaged including plates that present a convexly curved surface.
In FIGS. 3 to 5 the device 10 has a series of three pairs 20 , 21 , 22 of holes along the post so that as shown in FIGS. 4 a and 4 b the degree of protection of the plate 14 can vary depending on which pair of holes is selected to locate the pin.
The plate 14 is also asymmetrically located on the post to allow, as shown in FIGS. 5 a and 5 b , selection of the height of the plate 14 relative to the vehicle. The device may also be coupled to the bracket B in more than one orientation as shown in FIGS. 5 a and 5 b vertical inversion of the direction of the device 10 alters to the effective height of the plate 14 .
It is also understood that whilst the protector is preferably constructed of mild steel it can be chrome plated, painted or galvanised. The protector could also be made of reinforced plastics or reinforced fiberglass products with the inherent strength to resist low speed, low impact loads.
Although a locking pin is the preferred way of attaching the protector to the tow-bar it is understood that other forms of attachment are also envisaged including bolting the assembly to the tow-bar. | A protective device for use with a tow-bar having a towing hitch coupling. The protective device includes a substantially T-shaped member. The leg of the T is adapted to be coupled to the towing hitch coupling and the head of the T extends rearwardly of the towing vehicle past any rearwardly projecting components of the vehicle. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This is a division, of application Ser. No. 973,211 filed Dec. 26, 1978.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to nonionic surfactants and methods for making the same, with particular reference to nonionic surfactant compositions comprising monohydroxy alcohols capped with a polycarbonate.
(2) Brief Description of the Prior Art
In many industrial and household cleaning applications it is desirable or necessary to use a surfactant in the cleaning formulations to achieve satisfactory wetting and cleansing. Furthermore, in many of these industrial and household applications it is necessary to maintain a low level of foam during the cleaning operation. For example, surfactants that produce excessive foaming may be unsuitable in an industrial spray metal cleaning operation or for use as an active ingredient in detergents and rinse aids for household mechanical dishwashers.
One type of nonionic surfactant known in the art is the fatty acid ester of an alcohol ethoxylate, which ester is produced by condensing ethylene oxide with a detergent range alcohol, and then reacting such ethoxylated alcohol with fatty acids containing from 8 to 18 carbon atoms, or with the chlorides of such acids. Surfactants produced in this manner are described in U.S. Pat. No. 1,970,578 which teaches such surfactants as having excellent wetting, foaming and cleansing properties. However, surfactants of this type would not be satisfactory for uses where the suppression of foam is important.
Another type of nonionic surfactant known in the art is described in U.S. Pat. No. 3,539,518 which teaches a low foam, nonionic surfactant composition consisting essentially of a straight chain acyl group of 1 to 5 carbon atoms capped on an alcohol ethoxylate. More specifically the low foam surfactant composition consists of an alkoxypolyethoxycarboxylate compound which is produced by condensing ethylene oxide on an alcohol having 4 to 20 carbon atoms using means well known to the art, and then reacting this ethoxylate with a straight chain alkanoic acid having 1 to 5 carbon atoms or with the acyl halide or the anhydride of such acid.
SUMMARY
In general, the present invention provides new low foam, nonionic, polycarbonate type surfactant compositions and methods for producing the same. More specifically, the surfactant compositions comprise compounds represented by the following structural formulas: ##STR1## where R is an aliphatic, non-aromatic cycloaliphatic or aromatic group, y is a number from 1 to 10 and x is a number from 3 to 50.
In general, the process for producing the above surfactant compositions comprises reacting ethylene carbonate and a monohydroxy alcohol in the presence of an alkali metal salt catalyst at a temperature of about 130° C. to about 210° C. The monohydroxy alcohol may be capped with ethylene oxide before reacting it with ethylene carbonate or the reaction product of the ethylene carbonate/monohydroxy alcohol reaction may be further reacted with ethylene oxide to provide surfactants having different physical properties. The hydroxyethylation reaction of the alcohol or polycarbonate reaction product with ethylene oxide can be easily accomplished by using a basic catalyst, i.e. KOH, at a temperature of about 90° C. to about 120° C.
The reaction of the monohydroxy alcohol or ethoxylated alcohol with ethylene carbonate is represented by the following equations. ##STR2## The above equations illustrate that 50% of the available CO 2 in the ethylene carbonate is lost as a result of the formation of the carbonate intermediate illustrated by the first equation. Thus, the theoretical maximum yield of the polycarbonate block portion in the surfactant compositions is only 50% of the CO 2 available in the original ethylene carbonate reactant. Moreover, it is believed that the ethylene carbonate/alcohol reaction is initiated by an ethoxy ether radical resulting from the decomposition of ethylene carbonate to ethylene oxide and CO 2 . This ethoxy ether free radical initiation of the polycarbonate/alcohol reaction appears to be accurate since only about 38% to 43% of the CO 2 in the ethylene carbonate is normally retained as a carbonate radical in the final surfactant compositions.
Generally, about 2 to 20 moles, and more preferably about 3 to 10 moles, of ethylene carbonate per mole of monohydroxy alcohol or ethoxylated monohydroxy alcohol are reacted together to provide the hydrophobic properties in the final surfactant compositions. Also, about 3 to 50 moles, and preferably about 3 to 10 moles, of ethylene oxide per mole of monohydroxy alcohol or polycarbonate capped monohydroxy alcohol are reacted together to provide the hydrophilic properties in the final surfactant compositions.
The temperature of the ethylene carbonate/alcohol reaction is maintained between about 130° C. to about 210° C., and preferably between about 140° C. and about 170° C. A reaction temperature below 130° C. is not desirable since the formation of the polycarbonate block portion of the surfactant compositions is extremely slow at such low temperatures. Reaction temperatures above about 210° C. are also undesirable since ethylene carbonate will decompose into ethylene oxide and CO 2 at these elevated temperatures and the more reactive hydroxyethylation or polyether reactions will occur.
In order to form the polycarbonate block portion of the surfactant compositions, it is necessary that the ethylene carbonate/alcohol reaction be run in the presence of an alkali metal salt catalyst. Examples of useful alkali metal salt catalyst are sodium stannate, potassium stannate, sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, the sodium alkoxide of the monohydroxy alcohol and the potassium alkoxide of the monohydroxy alcohol. Sodium stannate has been found to be a particularly effective catalyst since high yields and low reaction time were obtained when it was used.
In view of the preceding discussion, it will be appreciated that the polycarbonate type surfactant products produced by this invention have, in all probability, some random ether radicals disposed within the polycarbonate block portion of the products since the theoretical 50 percent CO 2 reaction in the products is normally not achieved during the ethylene carbonate/alcohol reaction. Furthermore, it will be appreciated that the surfactant products are not a single compound in each instance but are a mixture of compounds of different molecular weights characterized by an average molecular weight depending on the termination point of the ether and/or carbonate blocks in each molecule.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description illustrates the manner in which the principles of the invention are applied but are not to be construed as limiting the scope of the invention. The following examples demonstrate the preparation of the polycarbonate type surfactants in accordance with the present invention.
EXAMPLE 1
A stirred reaction mixture of 2640 grams (30 moles) of ethylene carbonate, 558 grams (3 moles) of n-dodecanol and 12.0 grams (0.056 moles) of sodium stannate was heated to 170° C. for 24 hours in a reaction vessel under a nitrogen atmosphere. The mixture was then cooled to 130° C. and 30 grams of finely divided magnesium silicate and 60 grams of celite clay were added to purify the mixture. The mixture was continuously stirred at 130° C. for an additional 21 hours. At this point, the reaction product mixture was permitted to cool and was then filtered to remove the magnesium silicate and celite clay. 2000 grams of a pale yellow, transparent, viscous liquid reaction product was obtained which retained about 40 weight percent of the available CO 2 in the ethylene carbonate as a carbonate radical in the reaction product as determined by nuclear magnetic resonance spectral analysis.
EXAMPLE 2
A stirred reaction mixture of 44 grams (0.5 moles) of ethylene carbonate, 18.4 grams (0.1 moles) of cyclododecanol and 0.2 grams (0.001 moles) of sodium stannate was heated to 170° C. for 22 hours in a reaction vessel under a nitrogen atmosphere. The mixture was then cooled to 130° C. and 0.5 grams of magnesium silicate and 1.0 grams of celite clay were added to purify the mixture. The mixture was continuously stirred at 130° C. for an additional one hour. The reaction product mixture was permitted to cool and was then filtered to remove the magnesium silicate and celite clay. 35.1 grams of a pale yellow, transparent, viscous liquid reaction product was obtained which solidified on standing. About 40 weight percent of the available CO 2 in the ethylene carbonate was retained as a carbonate radical in the product.
EXAMPLE 3
The reaction conditions of Examples 1 and 2 were duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 20 grams (0.091 moles) of 4-nonylphenol and 0.2 grams (0.001 moles) of sodium stannate was reacted at 170° C. for 18 hours. The temperature of the mixture was reduced to 130° C., 1 gram of magnesium silicate and 1 gram of celite clay were added to the mixture and stirring was continued for one hour before cooling and filtering the reaction product. About 33 weight percent of the available CO 2 in the ethylene carbonate was retained as a carbonate radical in the reaction product.
EXAMPLE 4
The reaction conditions of Examples 1 and 2 were again duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 4.7 grams (0.025 moles) of n-dodecanol and 0.5 grams (0.002 moles) of sodium stannate was reacted at 150° C. for 40 hours. 30.3 grams of a yellow, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3. 41 weight percent of the available CO 2 was retained as a carbonate radical in the reaction product.
EXAMPLE 5
The reaction conditions of Examples 1 and 2 were again duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 5 grams (0.025 moles) of 2,4,6,8-tetramethyl-1-nonanol and 0.2 grams (0.001 moles) of sodium stannate was reacted at 150° C. for 20 hours. 26.4 grams of reaction product was obtained after purification and filtration as in Example 3. 40 weight percent of the available CO 2 was retained as a carbonate radical in the reaction product.
EXAMPLE 6
The reaction conditions of Examples 1 and 2 were again duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 6.3 grams (0.034 moles) of n-dodecanol and 0.01 grams (0.0001 moles) of potassium carbonate was reacted at 135° C. for 24 hours. The temperature of the mixture was then raised to 165° C. and reacted for an additional 44 hours. 26.9 grams of a dark brown, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3. 19 weight percent of the available CO 2 was retained as a carbonate radical in the reaction product.
EXAMPLE 7
37.3 grams (0.2 moles) of n-dodecanol and about 0.05 grams (0.002 moles) of sodium metal were mixed in a reaction vessel at 100° C. until the sodium dissolved. 88.1 grams (1.0 moles) of ethylene carbonate was added to the reaction vessel and the stirred mixture was heated to 200° C. and maintained at that temperature for 2 hours. 83.2 grams of a pale yellow, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3.
EXAMPLE 8
A stirred reaction mixture of 22 grams (0.25 moles) of ethylene carbonate, 16.6 grams (0.05 moles) of a mixture of n-dodecyl and n-tetradecyl triethoxylates (approximately 50/50 mole percent mixture) and 0.2 grams (0.001 moles) of sodium stannate was heated to 150° C. for 17 hours in a reaction vessel under a nitrogen atmosphere. 24.1 grams of a pale yellow, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3.
EXAMPLE 9
A stirred reaction mixture of 44 grams (0.5 moles) of ethylene carbonate, 23.6 grams (0.05 moles) of a mixture of n-dodecyl and n-tetradecyl hexaethoxylates (approximately 50/50 mole percent) and 0.2 grams (0.001 moles) of sodium stannate was heated to 150° C. for 24 hours. 48.1 grams of a pale yellow, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3.
EXAMPLE 10
27 grams (0.31 moles) of ethylene carbonate, 53.0 grams (0.10 moles) of 2,4,6,8 tetramethyl-1-nonyl octaethoxylate and 0.2 grams (0.001 moles) of sodium stannate were heated to 150° C. for 20 hours in a stirred reaction vessel as in Example 8. 64.2 grams of a pale yellow, transparent, viscous liquid reaction product was obtained after purification and filtration as in Example 3.
EXAMPLE 11
440 grams (5 moles) of ethylene carbonate, 530 grams (0.96 moles) of 2,4,6,8 tetramethyl-1-nonyl octaethoxylate and 2 grams (0.01 moles) of sodium stannate were heated to 160° C. for 24 hours in a stirred reaction vessel under a nitrogen atmosphere. The mixture was then cooled to 110° C., 10 grams of magnesium silicate and 10 grams of celite clay were added and the mixture was stirred for one hour. After filtration, 703 grams of a pale yellow, transparent, viscous liquid reaction product was obtained.
EXAMPLE 12
15.1 grams (0.17 moles) of ethylene carbonate, 17.1 grams (0.0087 moles) of tertrary octylphenol capped with 40 moles of ethylene oxide per mole of alcohol and 0.2 grams (0.001 moles) of sodium stannate were heated to 160° C. for 12 hours in a stirred reaction vessel as in Example 8. 10.7 grams of a tan solid reaction product was obtained after purification and filtration as in Example 3.
EXAMPLE 13
The reaction conditions of Example 5 were duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 20 grams (0.1 moles) of 2,4,6,8-tetramethyl-1-nonanol and 0.2 grams (0.001 moles) of sodium stannate was reacted at 150° C. for 20 hours. The reaction product was purified and filtered as in Example 3. 20 grams (0.038 moles) of this reaction product and 0.1 grams (0.0018 moles) of potassium hydroxide were placed in a reaction vessel and heated to 110° C. 7.5 grams (0.17 moles) of ethylene oxide were then added to the reaction vessel and the mixture was continuously stirred for 16 hours. 23.5 grams of a pale yellow, transparent, viscous liquid reaction product were obtained after purification and filtration as in Example 3.
EXAMPLE 14
The reaction conditions of Example 5 were again duplicated except that a mixture of 44 grams (0.5 moles) of ethylene carbonate, 10 grams (0.05 moles) of 2,4,6,8-tetramethyl-1-nonanol and 0.2 grams (0.001 moles) of sodium stannate was reacted at 150° C. for 20 hours. 20 grams (0.023 moles) of this reaction product, 5 grams (0.114 moles) of ethylene oxide and 0.1 grams (0.0018 moles) of potassium hydroxide were continuously stirred at 110° C. for 16 hours in a reaction vessel. 25.5 grams of a pale yellow, transparent, viscous liquid reaction product were obtained after purification and filtration as in Example 3.
The following Table 1 illustrates the mole ratios of ethylene carbonate and ethylene oxide reacted with each mole of alcohol and the catalyst used for the above examples.
TABLE 1______________________________________ Moles Moles MolesExample ROH.sup.1 Catalyst EO.sup.2 EC.sup.3 EO______________________________________1 C.sub.12 OH Na.sub.2 SnO.sub.3 -- 10 --2 Cyc . C.sub.12 OH Na.sub.2 SnO.sub.3 -- 5 -- ##STR3## Na.sub.2 SnO.sub.3 -- 5.5 --4 C.sub.12 OH Na.sub.2 SnO.sub.3 -- 20 --5 C.sub.13 OH Na.sub.2 SnO.sub.3 -- 20 --6 C.sub.12 OH K.sub.2 CO.sub.3 -- 14.7 --7 C.sub.12 OH Na -- 5 --8 C.sub.12 /C.sub.14OH Na.sub.2 SnO.sub.3 3 5 --9 C.sub.12 /C.sub.14OH Na.sub.2 SnO.sub.3 6 10 --10 C.sub.13 OH Na.sub.2 SnO.sub.3 8 3 --11 C.sub.13 OH Na.sub.2 SnO.sub.3 8 5 --12 ##STR4## Na.sub.2 SnO.sub.3 40 20 --13 C.sub.13 OH KOH -- 5 4.514 C.sub.13 OH KOH -- 10 4.9______________________________________ 1 Monohydroxy Alcohol 2 Ethylene Oxide 3 Ethylene Carbonate
The following Table 2 illustrates the surfactant properties for the reaction products of the above examples.
TABLE 2______________________________________ Inter- Surface facial Foam Height- Wetting CloudExam- Tension.sup.2 Tension.sup.3 Cms.sup.4 Time.sup.5 Pt..sup.6ple.sup.1 dynes/cm dynes/cm Initial Final secs °C.______________________________________1 28.2 1.3 1.5 0.5 >300 <252 37.4 1.0 0.5 0.2 >300 <253 31.3 9.4 0.8 0.7 >300 Insoluble4 31.8 1.3 *5.5 *3.0 *120 <255 32.7 1.6 *4.6 *0.8 >300 <256 33.3 5.8 19.6 8.9 75 <257 28.8 1.0 5.6 1.8 85 <258 31.7 2.2 23.0 6.6 45 359 29.8 1.8 6.1 2.3 61 --10 27.5 1.1 8.6 3.8 36 1811 26.8 1.7 6.0 1.6 40 2412 34.3 8.9 26.9 12.2 >300 --13 26.8 2.4 7.6 3.3 81 <514 29.6 1.2 8.4 3.8 66 <5______________________________________ .sup.1 0.1 weight percent concentration in deionized water. Numbers marke with * are 1.0 weight percent concentration in deionized water. .sup.2 ASTM D1331 test procedure. .sup.3 ASTM D1331 test procedure. .sup.4 Foam height was determined using the Hamilton Blender (Model No. 6363) Foam Test. 250 ml. of a 0.1% by weight surfactant/water solution wa whipped at low speed for one minute. The solution and foam were poured into a standard 500 ml. graduated cylinder having a 4.7 centimeter diameter. The foam height was measured immediately and after five minutes .sup.5 The Syndrome Tape Modification of the DravesClarkson wetting test using a nineinch strip of unmercerized natural cotton cloth tape attached to a one gram hook which in turn is attached to a forty gram weight by thread was used to determine wetting time. The solution concentration was 0.1% by weight surfactant in deionized water. The arrangement was dropped into a 500 ml. of the surfactant solution. When the tape was wetted, it dropped to the bottom of the graduated cylinder indicating the wetting time. .sup.6 ASTM D2024 test procedure except 0.1% concentration used in place of 1.0% concentration.
While certain representative embodiments have been shown in detail for the purpose of illustrating the invention, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. | Polycarbonate type nonionic surfactant compositions comprising monohydroxy alcohols capped with polycarbonate groups. More specifically, the surfactant compositions comprise aliphatic, nonaromatic cycloaliphatic or aromatic alcohols which have been capped with block polycarbonate groups formed by the reaction of the alcohols with ethylene carbonate in the presence of an alkali metal salt catalyst. The surfactant properties of the compositions may be varied by first reacting the alcohols with ethylene oxide to form a block polyether group cap on the alcohols before the reaction with ethylene carbonate or by further reacting the polycarbonate capped alcohols with ethylene oxide to form a terminal polyether block group. The surfactants formed are a random distribution mixture of compositions wherein 2 to 20 moles of ethylene carbonate and 3 to 50 moles of ethylene oxide per mole of the alcohols are reacted together. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to a fixing device for a tensioning member used in prestressed concrete, and more particularly to a fiber reinforced plastic tensioning member used in prestressed concrete.
2. Description of the Related Art
As is well known, a fixing device includes a separate type wedge 2 which has a tapered outer periphery and which grips each end of a tensioning member 1, and a grip 3 which accommodate the wedge 2, as shown in FIGS. 1A and 1B. The wedge 2 grips one end of the tensioning member and is set in the grip 3. Thereafter, tension is applied to the tensioning member 1 by means of a center hole jack or the like. At this time, due to the tensioning force, the wedge 2 is forced into the grip 3 to progressively increase the fixing or clamping force applied to the tensioning member 1.
In the fixing device of this type, the wedge 2 is designed so that the fixing force or wedge force increases at the tip end so as to effectively utilize the wedge force in the manner shown in FIG. 1B. Therefore, the fixing or retaining force maximizes at the smaller diameter end. As a result, a large stress (concentrated stress) is locally applied to the tensioning member at the portion mating with the small diameter end of the wedge 2.
This type of stress concentration is not a substantial problem in the case of the tensioning member made of steel. However, in case of a fiber reinforced plastic (hereinafter referred to as "FRP") tension member, this type of stress concentration creates substantial problems.
A tensile breaking test was performed by fixing a test sample of FRP provided with intersecting grooves as shown in FIG. 2. The specifications of the test sample are as follows:
Test Sample
Resin: Epoxy resin
Reinforcement Fiber: Carbon fiber (Fiber strength 500 kg/mm 2 )
Vf: 65%
Rod Configuration: FRP rod of 8 mm diameter with intersecting grooves (width 4×depth 0.12×pitch 40 mm)
The results of the test are shown in the following table 1.
TABLE 1__________________________________________________________________________Test Sample No. 1 2 3 4 5 6 7 8 9 10Break Force (ton) slip slip 10.5 9.8 9.5 slip 10.4 slip 8.8 9.2 11 12 13 14 15 16 17 18 19 20 Ave. slip 7.5 8.9 9.6 slip slip 9.7 8.9 slip 9.0 9.3__________________________________________________________________________
The results for twelve samples, which tested without slip, showed the average breakage load was 9.3 ton.
The original breakage tension force of the test sample is greater than or equal to 16 ton. Despite of this fact, breakage was caused at 9.3 tons in average. Therefore, sufficient tension force cannot be applied for the prestressed concrete.
One proposed solution of this problem has been disclosed in Japanese Unexamined Utility Model Publication (Kokai) No. Showa 61-161327. The prior art disclosed in the above-identified publication is illustrated in FIG. 3. As shown, the proposal employs a mesh-form cover body 4 formed of metal wire. The cover body 4 is disposed between the wedge 2 and the tensioning member 1.
In the known construction as illustrated in FIG. 3, a test was performed employing a cover body 4 formed of brass wire of 0.0066 mm diameter and 150 mesh. In this case, the fixing force applied from the wedge 2 to the tensioning member 1 is as illustrated by the solid line in FIG. 4. As will be appreciated from a comparison of the solid line with the broken line which represents the fixing force in the case where the cover body 4 is not employed, stress concentration can be reduced by a certain degree. However, line contact due to the mesh-structure of the cover body concentrically received the fixing force resulted in stress concentration. The following table 2 shows the results of tensile breaking tests performed employing test samples having substantially the same specifications as the former example.
TABLE 2______________________________________Teat Sample No. 1 2 3 4 5 6 7 Ave.Break Force (ton) 6.9 5.4 7.1 5.4 6.9 5.2 slip 6.2______________________________________
As seen, the average breakage load was 6.2 tons which is less than that of the former example of FIG. 1.
Similar test was also performed with employing the cover body formed of brass wire having a 0.193 mm diameter and 50 mesh. The result of the test is shown in the following table 3.
TABLE 3______________________________________Teat Sample No. 1 2 3 4 5 6 7 Ave.Break Force (ton) 5.4 7.2 6.3 5.6 6.4 5.8 5.8 6.1______________________________________
As shown, the average shearing load is 6.1 which is worse than that of the former example.
Japanese Unexamined Utility Model Publication No. Heisei 4-116520 and Japanese Examined Utility Model Publication (Kokoku) No. Heisei 4-6452 respectively disclose second and third examples of fixing bodies.
In the second prior art, it is proposed to provide an elastic layer between the wedge and the tensioning member so that the tensioning member can be gripped softly. This prior art employs a soft material, such as rubber, to form the elastic layer. In this case, the deformation magnitude at small stress levels becomes substantial. Therefore, before sufficient tension can be applied to the tensioning member, the elastic layer is apt to become expanded and loose and to lower the tension.
On the other hand, in case of the foregoing third example of prior art, a buffer member is disposed between the wedge and the tensioning member. For both of the buffer member and the contact surface of the wedge, engaging portions between projections and recesses are formed. Also, a recessed groove is formed on the inner periphery of the buffer member. In such construction, it is required to provide the engaging portion of the projections and recesses on the inner periphery of the wedge and on the outer periphery of the buffer member, and a recessed groove on the inner periphery of the buffer member. This causes substantial increase of the processing cost. In addition, in this third prior art, due to the presence of the recessed groove on the inner periphery of the buffer member and the buffer member being separated in the circumferential direction, a portion of the buffer member may not contact when under tension. Therefore, similarly to the foregoing second prior art, this portion serves as a cause of stress concentration.
As set forth above, in the fixing device for the tensioning member in the prior art, it has been not possible to provide sufficient tension force.
The tensioning member to be employed in the prestressed concrete, it is required to introduce high tension force for providing sufficient tension for the prestressed concrete, in either case of the FRP tensioning member or the metallic tensioning member. Therefore, the required tensile strength of the tensioning member is substantially high for introducing high tension force even in the case where typical steel reinforcement is employed in the prestressed concrete.
In order to obtain sufficient tension force, it becomes necessary to provide a substantially high holding or clamping force for the wedge of the fixing device. This potentially results in an increase in the concentrated stress at the tip end of the wedge to cause breakage of the tensioning member so that the breakage of the tensioning member due to stress concentration may be caused before occurrence of breakage due to excessive tension. Namely, since the breaking force upon introduction of the tensioning force depends on the stress concentration at the tip end of the wedge, it becomes necessary to provide a buffer member for buffering stress concentration.
In particular, in case of the tensioning member formed of the FRP, while the strength in the longitudinal direction (direction of orientation of the fiber) is substantially high, it has much lower strength against local tension force or shearing force associated with stress concentration by the wedge, in comparison with the metallic tensioning member. Therefore, when a FRP tensioning member is employed, it is inherently required to realize a high tension force, a high holding force associated with the high tension force and stress distribution at the fixing portion.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a fixing device for a tensioning member of a prestressed concrete, in which a holding force of a wedge may uniformly act on the overall peripheral surface of the tensioning member mating with the wedge.
Another object of the invention is to provide a fixing device which will never cause stress concentration at the fixing surface and can add a tensile breakage force substantially close to an original tensile breakage force to an FRP tensioning member.
According to one aspect of the invention, fixing device for a tensioning member for a prestressed concrete comprises:
a stationary grip through which the tensioning member extends;
a wedge press fitted to the grip with holding the tensioning member for fixing the tensioning member relative to the grip under a given tension; and
a buffer member disposed between the tensioning member and the wedge, the buffer member having elasticity and plasticity.
The buffer member may be formed into a tubular configuration. In the alternative, the buffer member may be formed into a plate-like configuration.
At least one of a mating pair of the buffer member and the tensioning member and a mating pair of the buffer member and the wedge may be mechanically coupled for integrity.
The buffer member may be formed of a material having both elasticity and plasticity. Preferably, the buffer member is formed of a material selected among aluminum, aluminum alloy, copper, copper alloy, fiber reinforced plastic, a tempered iron and composite material thereof.
The buffer member may be formed into a configuration selected among a tubular configuration and a plate form configuration to be wrapped around the tensioning member. In such case, it is preferred that the buffer member is formed with at least one slit extending in axial direction for a length at least one half of the axial length of the wedge. The buffer member may be formed with a plurality of slits with a given interval in the circumferential direction. Also, the axial length of the slit may be longer than the axial length of the wedge.
According to another aspect of the invention, a fixing device for a tensioning member for a prestressed concrete comprises:
a stationary grip through the tensioning member extends;
a wedge press fitted to the grip with holding the tensioning member for fixing the tensioning member relative to the grip under a given tension, the wedge generating progressively increasing gripping force for gripping the tensioning member according to increasing of penetration magnitude into the grip; and
a buffer member disposed between the external surface of the tensioning member and the internal surface of the wedge, the buffer member having elasticity and plasticity.
The buffer member may be formed with a slit.
According to a still further aspect, a tensioning structure for a prestressed concrete comprises:
an elongated tension carrier;
stationary member having an opening through which the tension carrier extends;
tension retainer cooperated with the tension carrier and stationary member for fixing the tension carrier relative to the stationary member in a condition where a predetermined magnitude of tension force is applied to the tension carrier;
stress distributor disposed between the tension carrier and the tension retainer, the stress distributor having a first surface mating with the surface of the tension carrier and having surface configuration complementary with the surface configuration of the tension carrier and a second surface mating with the surface of the tension retainer and having surface configuration complementary with the surface configuration of the tension retainer for distributing retaining force of the tension retainer to substantially entire surface of the tension carrier.
The stress distributor may be made of a material which can be deformed elastically and plastically. Also, the material of the stress distributor may have a shear strength withstanding to a shear stress at the predetermined magnitude of tension force.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiment of the invention, which, however, should not be taken to be limitative to the present invention, but are for explanation and understanding only.
In the drawings:
FIGS. 1A and 1B are respectively an exploded perspective view and a section showing features of the conventional tensioning member;
FIG. 2 is a side elevation of the tension device used in the conventional fixing device;
FIG. 3 is a section showing the features of another conventional fixing device;
FIG. 4 is an illustration showing the stress distribution produced by the conventional fixing device shown in FIG. 3;
FIG. 5 is a section showing features of the preferred embodiment of the fixing portion according to the present invention;
FIG. 6 is a perspective view showing another embodiment of the fixing device according to the invention;
FIG. 7 is an exploded perspective view showing the case wherein the fixing device is assembled with a plastic film disposed between the wedge and a grip; and
FIG. 8 is a perspective exploded view showing an arrangement wherein a buffer member is formed from plates of material which are wrapped onto the exterior of a tensioning rod member.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will be discussed in detail hereinafter with reference to FIGS. 5 to 7. In the following disclosure, the reference numerals used in FIGS. 1 to 4 are also used in FIGS. 5 to 7 to represent like elements. Therefore, a detailed discussion for such common elements will be omitted for avoiding redundant discussion and keeping the disclosure simple and to facilitate understanding of the invention. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to those skilled in the art that the present invention may be practiced without these specific details. It will also be noted that well-known structures are not shown in detail in order to avoid obscuring the features of the present invention.
A sleeve-like tubular body 5 is formed from a material having both elasticity and plasticity. Such material will be hereinafter referred to as "elastoplastic material" or "elastoplastic body" is disposed between the FRP tensioning member 1 and the separate type wedge 2. In this embodiment, aluminum is employed as the elastoplastic material. The elastoplastic tubular body 5 is fitted between the tensioning member 1 and the wedge 2 tightly and without any gap therebetween.
On the other hand, the FRP tensioning member 1 is formed from a reinforcement fiber, such as inorganic fiber including carbon fiber, glass fiber or the like, aramide fiber, polyethylene fiber or the like, and a matrix resin including a thermosetting resin, such as epoxy resin, unsaturated polyester resin or the like and a thermoplastic resin, a nylon resin, etc. In the illustrated embodiment, the tensioning member is formed of a carbon fiber reinforced epoxy resin composite body.
For performing tensile breaking test, test samples were prepared according to the following specification.
Test Sample
Resin: Epoxy resin
Reinforcement Fiber: Carbon fiber (Fiber strength 500 kg/mm 2 )
Vf: 65%
Rod Configuration: FRP rod of 8 mm diameter with intersecting grooves (width 4×depth 0.12×pitch 40 mm)
As will be appreciated, the test samples were identical in specification to those used for the tensile breaking test of the conventional devices.
Tensile breaking test was performed in the following manner. As shown in FIG. 5, the test sample is fixed by the fixing means by interpositioning the tubular body 5 under tension. The tubular body 5 used in the test was an aluminum tube having 10 mm of external diameter, 8.05 mm of internal diameter (actually measured value: nominal value in brochure was 8.00 mm). After setting, tension was applied to the test sample by a center hole jack until breakage occured. The load upon breakage was measured by a load cell. As the material of the aluminum tube, a material of #1050 of JIS standard was used.
The result of the tensile breaking test is shown in the following table 4.
TABLE 4__________________________________________________________________________Test Sample No. 1 2 3 4 5 6 7 8 9 10 Ave.Brake Force (ton) 12.9 132 13.2 12.7 13.0 13.5 13.4 13.8 13.7 12.5 13.2__________________________________________________________________________
From the result of test, the average value of the tensile breakage test was found to be 13.2 tons which is much greater than any of the conventional fixing devices disclosed above. Also, since the original tensile breakage force of the FRP tensioning member is approximately 16 tons, it can be said that the tensile breakage force achieved by this embodiment is satisfactorily close to the original tensile breakage force of the FRP tensioning member. Furthermore, fluctuation of the results is much smaller than the prior art to provide stable test results.
In the embodiment of the present invention, the tubular body 5 has its entire inner and outer peripheral surfaces are respectively fitted onto the external periphery of the tensioning member 1 and the internal periphery of the wedge 2. Therefore, when the tubular body 5 is compressed by the wedge 2, the tubular body 5, in turn, exerts compression force onto the entire external periphery of the tensioning member 1.
As a result, the fixing force is unified not only in the circumferential direction but also in the lateral direction. At this time, the distribution of the stress in the axial direction becomes substantially uniform through the entire length of the wedge. Therefore, the problem of the stress concentration can be reduced. Also, the crushed portion of the tubular body penetrates into the mating clearance between the separated fractions of the wedge 2.
It is considered that the illustrated embodiment of the present invention has achieved superior results as shown in the table 4 due to the behavior of the tubular body 5 as set forth above. Also, as set forth above, with this embodiment, the FRP tensioning member may be fixed at a tensile breakage load substantially close to the original tensile strength (16 tons) of the FRP tensioning member.
Results of tensile breaking tests in the terms differentiated from those in the former tensile breaking tests will be briefly discussed. In the additional tests, the manner of fixing the tensioning member, the test sample and testing device were the same as the former tests. The only difference was in the depth of the grooves formed in the tensioning member 1. The results of tests are shown in the following tables 5, 6 and 7. Table 5 shows the case where the depth of the groove is zero, table 6 shows the case where the depth of the groove is 0.5 mm, and table 7 shows the case where the depth of the groove is 0.7 mm. It should be noted that the average value of the result for the table 7 is the average obtained with respect to seven tests wherein slip did not occur.
TABLE 5__________________________________________________________________________Test Sample No. 1 2 3 4 5 6 7 8 9 10 Ave.Brake Force (ton) 12.8 13.0 13.5 12.5 13.3 13.3 13.8 12.9 12.9 13.1 13.1__________________________________________________________________________
TABLE 6__________________________________________________________________________Test Sample No. 1 2 3 4 5 6 7 8 9 10 Ave.Brake Force (ton) 12.6 12.0 12.8 12.2 11.9 12.9 13.0 13.0 12.2 12.3 12.5__________________________________________________________________________
TABLE 7__________________________________________________________________________Test Sample No. 1 2 3 4 5 6 7 8 9 10 Ave.Brake Force (ton) slip 12.0 11.3 10.0 12.3 slip 11.0 slip 10.3 11.8 11.2__________________________________________________________________________
As will be clear from the above, the preferred depth of the groove on the tensioning member 1 is less than 0.5 mm.
It should be noted that while the foregoing embodiment employs a tubular body 5 as the buffer, the configuration of the buffer member is not limited to a tubular configuration and can be of any suitable configuration. For instance, the buffer member may be in the form of the tube with a slit extending in the entire axial length or in a form of a plate or sheet which is wound or wrapped around the tensioning member. In short, any configuration establishing surface-to-surface contact between the buffer member with tensioning member and the wedge may be applicable.
In the preferred construction, the tubular body 5 is formed with at least one axially extending slit. The length of the slit is preferably longer than or equal to half of the length of the wedge, and more preferably longer than the entire length of the wedge 2. In such case, the tubular body 5 is positioned so that the slit is positioned at least at the position mating with the small diameter end of the wedge. The preferred number of slits is four in that the slits may be arranged around the tensioning member at constant intervals. Then, upon deformation of the tubular body 5, deformation may be caused uniformly through the entire circumference of the tensioning member 1 to maintain firm contact with the tensioning member 1 and the wedge 2. In this connection, when the tubular body 5 is employed, it is preferred to form four slits at approximately 90° intervals. On the other hand, in the case where the buffer member is formed of plate members, and two plate members are arranged in opposition on the tensioning member, one slit is formed for each individual plate member. In addition, when a reduction of the weight of the buffer member is desired, it may be possible to form material reduction holes through the tubular body or the plate member to the extent that no stress concentration is caused.
As set forth above, the buffer member, such as the tubular body or the plate member, is formed with the elastoplastic body. As the elastoplastic body, a material having both elasticity and plasticity is selected so as to permit elastic deformation in response to application of stress without causing brittle breakage and further permit plastic deformation to conform with the surface configurations of the tensioning member 1 and/or the wedge 2.
As examples of the material having both of the elasticity and plasticity, various metals, rubber, resin and so forth may be considered. In case of the rubber as the elastic body, it may be possible to prevent slippage and stress concentration since the rubber may establish uniform contact with the tensioning member. However, since the rubber has a large elastic deformation magnitude and a low critical point with respect to stress, the deformation magnitude of the rubber will be excessive and cause loosing of the tensioning member 1. Alternatively, the rubber may break even at a low tension force due to the low critical point. Therefore, rubber may not be considered as suitable material for forming the buffer body.
On the other hand, material which undergoes only plastic deformation without causing elastic or resilient deformation, is also available. Such material includes lead, solder and so forth. However, when such a material is employed, a slight deformation due to the exertion of excessive force or thermal expansion, etc., is apt to cause corresponding plastic deformation of the material. Such plastic deformation possibly becomes a cause of slippage. Therefore, the material which only features plastic deformation, is apt not to be suitable.
In case of plastic, since plastics generally have a low critical point, they are not suitable for the reason set out with respect to rubber. However, in the case of fiber reinforced composite material, a reasonable stress buffer effect may be expected. For instance, a tubular body formed of polyacetal resin (available from Polyplastic Co.) containing 10% of carbon fiber and having a 1 mm of wall thickness, exhibited comparable result to that shown in the foregoing table 4.
From the above, as the buffer material, in addition to aluminum, aluminum alloy, copper, copper alloy, fiber reinforced plastic may be suitable. In addition, tempered iron may also be applicable as the buffer material.
Also, composite material, such as a laminate of the foregoing metal and plastic, or three layer structure of metal-plastic-metal may be applicable for forming the buffer member. For instance, aluminum-polyethylene-aluminum laminate body (having respective thickness of 0.5-0.05-0.5 mm) may be employed for forming the tubular body set forth above.
Also, the configuration of the wedge 2 is not specified to the illustrated construction. Namely, while the illustrated embodiment employs a two piece construction of the wedge, the wedge may be constructed in a three piece construction or in a one piece construction with an axially extending slit 2a.
It should be noted that while the wedge 2 may be formed of a steel, it is preferred to form the wedge with aluminum or aluminum alloy for capability of appropriate plastic deformation. Particularly, in case of large size fixing device, the wedge of the light metal, such as aluminum or so forth, is preferred in view of workability.
Upon setting of the tensioning member 1 to the fixing device, it may be possible to mechanically couple the buffer member and the tensioning member 1, buffer member and the wedge or all of the tensioning member 1, the buffer member and the wedge, by way of bonding, clamping or screw fastening and so forth, in advance.
Furthermore, while the foregoing discussion is given where the tensioning member has a circular cross-section, the present invention is equally applicable for the tensioning members having cross-sectional configurations other than circular. For instance, the present invention may be applicable for the case where the tensioning member has a quadrangular configuration (such as plate form). It should be naturally understood that, in such case, the wedge should have the complementary configuration to the tensioning member.
In practice, the tensioning member 1 is provided a strength higher than or equal to 100 kg/mm 2 . In case of the tensioning member with the circular cross-section, the diameter may be within a range of approximately 1 to 25 mm.
Next, consideration will be given for the mechanism of fixing of the tensioning member 1 by the wedge.
As shown in FIG. 5, with increasing tension force F, the wedge 2 penetrates into the grip 3 to cause wedge effect to increase the depression force P applied for the tensioning member.
However, if a large tension force is applied to the tensioning member having quite large tensile strength (high strength and large diameter), the penetration magnitude of the wedge into the grip 3 is progressively increased. Associated with this, the depression force P may grow, become excessively large and cause breakage of the tensioning member 1 despite of the fact that stress concentration is prevented by disposing the buffer member between the tensioning member 1 and the wedge.
In order to eliminate such phenomenon, it becomes necessary to employ a material having high work-hardening performance as the buffer member.
Upon fixing the tensioning member 1 by engaging the tensioning member to the wedge 2 via the buffer member and engaging the wedge to the grip, initial slip of the tensioning member 1 may be prevented by pressing the wedge 2 into the grip 3 to cause initial deformation of the buffer member in advance of application of the tension force.
For this purpose, it is the simplest way to hammer the wedge 2 into the grip 3. However, due to frictional resistance between the wedge 2 and grip 3, substantial impact may be required. At this time, it is possible to damage the tensioning member 1. Therefore, it is preferred to dispose an anti-friction material between the wedge and the grip.
As the anti-friction material, a lubricant oil; plastic film and so forth may be used. FIG. 7 shows an example employing the plastic film as the anti-friction material. Namely, when press fitting the wedge 2 into the grip 3, a vinyl film 6 is disposed therebetween. At this time, in view of workability, the vinyl film 6 is preliminarily formed into a bag form to be set with the wedge.
As set forth above, according to the present invention, by disposing the elastoplastic buffer member between the tensioning member 1 and the wedge 2, the buffer member may cause deformation upon press fitting the wedge into the grip for fixing the tensioning member. As a result of the deformation, the buffer member is formed to have the external surface configuration complementary with the internal surface configuration of the wedge and the internal surface configuration complementary with the external surface configuration of the tensioning member. Thus, the buffer member may be tightly fitted with both of the tightening member and the wedge. Under these conditions, the wedge is penetrated into the grip to cause further deformation of the buffer member.
Therefore, by tensioning operation of the tensioning member, the buffer member is caused deformation and completely fixed to the tensioning member. This results in an anchoring effect to prevent slippage between the tightening member and the buffer member. At this time, since complete surface-to-surface contact is established between the buffer member and the tightening member including the groove in the tensioning member, stress can be distributed over the entire mating surface between the tightening member and the buffer member to successfully avoid local stress concentration.
At the same time, since the part of the material of the buffer member may penetrate into the slits formed in the wedge during deformation, firm fitting can be established between the wedge and the buffer member to successfully prevent slippage therebetween.
Although the invention has been illustrated and described with respect to exemplary embodiment thereof, it should be understood by those skilled in the art that the foregoing and various other changes, omissions and additions may be made therein and thereto, without departing from the spirit and scope of the present invention. Therefore, the present invention should not be understood as limited to the specific embodiment set out above but to include all possible embodiments which can be embodied within a scope encompassed and equivalents thereof with respect to the feature set out in the appended claims. | A fixing device for a tensioning member of a prestressed concrete may unimly act holding force for the tensioning member on the overall peripheral surface of the tensioning member mating with the wedge. The device includes a stationary grip through which the tensioning member extends, a wedge press fitted to the grip with holding the tensioning member for fixing the tensioning member relative to the grip under a given tension, and a buffer member disposed between the tensioning member and the wedge, the buffer member having both elasticity and plasticity. | 4 |
BACKGROUND OF THE INVENTION
This invention relates generally to an improved cladding for covering exterior facing surfaces of wood, foam, plastic, particle board, vinyl and urethane trim members of buildings such as window and exterior door frame trim and moldings for exterior siding. More specifically, this invention relates to such cladding which features a flap hingably connected to a surface portion thereof which has an open position tilted away from the surface portion to permit fasteners to be driven through the surface portion and a closed position flush against the surface portion for concealing holes through the surface portion through which fasteners have been driven to fasten the cladding covered trim member to an adjacent structural member.
Broadly speaking, semi-flexible plastic cladding for covering the otherwise exposed exterior surfaces of trim members, such as, for example, wooden trim members, which are fastened to adjacent wooden structural elements are known in the prior art. In some cases such prior art cladding can be applied to trim members after fasteners have been driven through the trim member to secure it to an adjacent wooden supporting member. See, for example, U.S. Pat. No. 3,478,478 issued in the name of D. F. Luebs on Nov. 18, 1969 for a snap-on plastic cover. Obviously, in cases such as this, no unsightly holes need be made in the cladding and the snap-on cladding will conceal the fastener heads in the surface of the trim member from view. See also the liners used to cover nails driven through siding into supporting wooden structural members in U.S. Pat. Nos. 3,902,292 and 3,974,606 issued to J. N. LaBorde on Sep. 2, 1975 and Aug. 17, 1976, respectively. In the two latter mentioned patents, however, the liners stand off of the members being covered to conceal nails, but do not fit those members in a close conforming manner.
By means of my invention, the cladding can be advantageously applied to a trim element in a close fitting manner before the trim element is fastened to a supporting structural element and, yet, the fasteners and holes made through the cladding by or for the fasteners can still be concealed from view.
SUMMARY OF THE INVENTION
It is an object of my invention to provide an improved cladding for covering a trim element which is adapted to be joined by fasteners driven through the cladding and trim element to an adjacent structural member of a building, the improvement being in means for concealing the fastener holes in the cladding from view.
Briefly, in accordance with my invention, there is provided an improved cladding of the type which is conventionally adapted to cover externally facing surfaces of an external trim element of a building structure and through which fasteners can be driven in order to join the trim element to an adjacent element of the structure. The improvement comprises a tiltable flap hingably attached to and along the cladding. The flap has an open position tilted away from an externally facing surface portion of the cladding to permit fasteners to be driven through the surface portion to join the trim element to the adjacent structural element. The flap also has a closed, operative position which is parallel to the surface portion to conceal holes in the surface portion from view through which the fasteners are driven.
These and other objects, features and advantages of my invention will become apparent to those skilled in the art from the following detailed description and attached drawings upon which, by way of example, only the preferred embodiments of my invention are described and illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of a corner portion of an exterior wooden doorjamb and attached wooden brick molding trim element, exterior facing surfaces of the jamb and molding being covered by plastic cladding, the cladding of the brick molding having provision for concealing fasteners used to attach the wood members together, thus illustrating a preferred embodiment of my invention.
FIG. 2 shows a cross-sectional elevation view of the jamb and molding of FIG. 1 as viewed along cross-section lines 2--2 of the latter mentioned figure.
FIG. 2a shows an enlarged detail view of a fragment of the molding cover and trim element of FIGS. 1-2, the same as viewed in the latter mentioned figure.
FIG. 3 shows a cross-sectional plan view of the jamb and molding of FIGS. 1-2 as viewed along cross-section lines 3--3 of FIG. 2, with portions of a door sill assembly at the base of the jamb and molding being added.
FIG. 4 shows a cross-sectional plan view of a portion of a door jamb, door sill and attached brick molding, the same as viewed in FIG. 3, thus illustrating another important embodiment of my invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing figures and, in particular, to FIGS. 1, 2, 2a and 3 there is shown, in a preferred embodiment of my invention, an exterior doorway assembly, generally designated 10, for a residence or other building structure. The assembly 10 includes a conventional wooden door jamb 11 and a conventional wooden trim element, specifically, a molding or casing 12 for siding such as, for example, brick, stone, wood or vinyl, the casing being attached to the jamb by suitable spaced apart fasteners such as nails 14. The jamb 11 contains a conventional weather strip 16 against which an exterior door, not shown, can be closed, and a conventional semi-flexible, preferably plastic cladding or cover 18 which snap fits in close conforming relation over exterior facing surfaces of the jamb. The molding 12 also contains an improved semi-flexible, preferably plastic cladding or cover, generally designated 20, with which this invention deals, which cladding is preferably constructed of the same commonly used material as that of the jamb cover 18. The cladding 20 covers the exterior facing surfaces of the molding 12 in, preferably, a close conforming manner.
Conventionally, the jamb 11 contains three members, one of which defines the upper surface of the doorway opening as shown in cross-section at 11 in FIG. 2 and two vertically extending side members defining opposite sides of the doorway opening, only one of which side members is shown in the drawings, it being the same against which the door closes as shown in cross-section at 11 in FIG. 3. The upper member of the jamb 11 normally rests upon the upper ends of the two opposing side members. At the lower end of the jamb 11 and molding 12 there is shown a conventional door sill assembly 21 extending across the base of the doorway opening. See FIG. 3.
Also, conventionally, the molding 12 can be constructed of three members, one of which is an upper member which is attached to and along a front facing vertical surface of the upper member of the jamb 11 as shown in cross-section at 12 in FIG. 1. The remaining two members of the molding 12 are two side members which are attached to and along front facing, vertically extending surfaces of the opposing side members of the jamb 11, one of which molding side members is shown in cross-section as at 12 in FIG. 3. Each of the side members of the molding 12 are conventionally adjoined with opposite ends of the upper molding member to form two miter joints, only one of which is shown as at 22 in FIG. 1.
The molding cover 20 is preferably also formed in three segments, one of which covers the externally facing surfaces of the upper member of the molding 12 as shown in cross-section in FIG. 1. The other two segments cover the externally facing surfaces of the opposing side members of the molding 12, one of which side member cover segments is shown in cross-section at 20 in FIG. 3. The side member segments of the cover 20 have upper ends which are mitered in conformity with corresponding ends of the upper member segment to form a mitered abutment 52 aligned with the miter joint 22 in the molding 12, one of which is shown in FIG. 1 at 22. An upper surface 24 of the cover 20 (See FIGS. 1-2) and lateral side surfaces 26 thereof, only one of which is shown as at 26 in FIG. 3, overlap the back surfaces of the members of the molding 12, as at 28. The overlaps 28 can be suitably fastened to and along the back surfaces of the molding 12 such as by means of a series of spaced apart staples 30.
The improvement in the otherwise conventional molding cover 20 is a provision for concealing unsightly and otherwise weather degradable fastener holes formed through a front surface portion 34 of the cover 20 by the nails 14 which are necessary to adjoin the molding 12 to the jamb 11 as previously explained. To accomplish this result, a tiltable flap 32 is provided which is hingably attached, preferably, to and along external, door opening defining edge portions of the three segments of the cover 20, which flap can be opened away from the molding 12, as shown in full in FIGS. 1 and 3 and in phantom at 32' in FIG. 2, to permit nails 14 to be driven through a flap underlying surface portion 34 of the cover. The flap 32 preferably employs a conventional live hinge 36 (See FIGS. 1 and 3) at its joinder with a doorway facing surface 38 of the cover 20. The flap 32 preferably includes a free end which contains an essentially perpendicularly extending end portion 40 adapted to friction fit tightly into and along a groove 42 formed in and along a front facing surface portion of the molding 12, into which a blind slot in a front surface of the cover 20 projects. The groove or blind slot in the cover 20 closely conforms to and fits tightly within the groove in the molding 12. The end portion 40 of the present example contains a springable, projecting member 44 which projects outwardly at an oblique angle, away from the end portion when relaxed and when the end portion is removed from the groove 42 as seen at 44 in FIG. 2. Upon insertion of the end portion 40 into the groove 42, the member 44 is forcibly tilted against the end portion to help secure the end portion tightly within the groove 42 as shown best in FIG. 2a. The end portion 40 may also contain a series of raised, spaced apart ribs 46 which fit within conforming, spaced apart slots 48 in the groove 42 when snap fit into the latter. In this manner, the open flap 32 can be pushed by hand and pressed flat against the underlying surface portion 34, whereby the end portion 40 holds the flap in a closed position against the surface portion 34 to conceal the unsightly fastener holes in the underlying surface portion from view, as shown at 50. The groove 42 is thus located on and along a border of the surface portion 50. The flap 32 and end portion 40 also act as a weather seal to keep moisture from continually seeping into and around the holes 50 which would otherwise occur in the absence thereof. Opposing ends of the flaps 32 in adjacent segments of the cover 20 also form mitered abutments when closed in their operative positions to thus overlie portions of the mitered joints 22 in the molding. See miter 52 in FIG. 1.
Referring now to FIG. 4 another important embodiment of my invention is shown. The door jamb 11, door jamb cover 18, door sill 21 and molding 12 shown in this figure are the same as in the previous example of FIGS. 1, 2, 2a and 3. A cover or cladding 54 for the molding 12 is also identical with the cover 20 of the previous example except for the manner in which a fastener concealing flap 56 snap fits into the cover at its free end upon closure to conceal the hole through which of the nail 14 is driven. In this example, a wall or edge of the cover 54 into which the free end of the flap 56 locks when closed contains an elongated indention or groove 58. The free end of the flap 56 thus snaps into groove 58 to hold the flap flush against an underlying surface portion 60 of the cover 54 to thus conceal the holes 50 in the underlying cover portion through which the nails 14 were driven prior to closure thereof.
The cladding or cover of my invention may thus be used to conceal the holes made in a surface portion thereof by or for any of the usual types of fasteners, including not only nails, as shown in the foregoing examples, but also by threaded fasteners of all kinds, pins and the like, of a type suitable for fastening an exterior trim element to an adjacent element in a building structure. The flap containing cover of my invention can be adapted for use with a wide variety of trim elements to conceal fastener holes other than brick molding as, for example, moldings for other types of siding such as stone, block, wood, and the like. Such a cover can also be adapted for use with window frames or casings, trim elements therefor and, as here, with door frame trim elements of the type which are to be adjoined by fasteners to other adjacent structural elements.
The cladding of my invention can not only be used with wooden trim members but also with such members constructed of foam, plastic, particle board, vinyl and urethane. In such cases a foam trim member could be extruded and then, when sufficiently cooled or cured, a plastic jacket could be co-extruded thereon to form the cladding containing the flap.
While the present invention has been explained with respect to specific details of certain preferred embodiments thereof, it is not intended that such details limit the scope and coverage of this patent other than as specifically set forth in the following claims. | An improved cladding for covering the exterior facing surfaces of an exterior trim member of a building structure is disclosed which includes means for concealing holes in an exterior surface portion of the cladding formed by or for fasteners driven through the surface portion into the trim member to join the trim member to an adjacent structural member. The concealing means includes a tiltable flap hingably attached along one edge portion thereof to an exterior corner of the cladding. The flap is tiltable between an open position wherein fasteners can be driven through a flap underlying surface portion of the cladding and a closed, operative position wherein the flap is held flush against the underlying surface portion of the cladding to conceal the fastener holes therein from view. Different arrangements for securing the flap in the closed, operative position are also disclosed. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to systems and methods for controlling the flow of a conductive fluid over a surface, and more particularly to a system and method that uses magnetic and electric fields to create Lorentz forces that affect the flow of a conductive fluid in a controlled manner near the boundary layer of a control tile, or a matrix of control tiles, immersed in the conductive fluid.
Conductive fluids naturally occur in many different settings. Note, that for purposes of this application, the term "fluid" is used in its broad scientific sense to connote a liquid or a gas. Wherever such a conductive fluid is encountered, there is typically a need or desire to move a vessel or other object through the conductive fluid using a minimal amount of energy. One way to meet this need is to design such vessel or object so that the conductive fluid flows over the surface thereof with a minimal amount of drag.
Perhaps the most common example of a conductive fluid is sea water, which covers a significant percentage of the earth's surface. Ocean-going vessels traveling through such fluid, e.g., ships or submarines, must exert significant amounts of energy in order to successfully navigate through such fluid (sea water) at a suitable speed. Hence, much attention has been directed over the years to optimally design the hull or shape of an ocean-going vessel in order reduce the drag (friction) the fluid encounters as it passes over the surface of the vessel. Despite such efforts, however, there remains a continual need to further reduce the drag encountered by conductive fluids passing over the surface of such vessels to thereby make the movement of such vessels through the fluid more efficient.
As is known in the art, a viscous fluid, and a body completely immersed in the fluid, form a boundary layer at the body's surface when the fluid and the body move relative to each other. That is, the layer of fluid in contact with the body is essentially at rest, while in an area removed from the body, the fluid is moving at its free-stream velocity. The region between the body and that area is known as a boundary layer. Where the fluid is a conductive fluid, electromagnetic forces may be introduced into the boundary layer in an attempt to alter the boundary layer characteristics. See, e.g., U.S. Pat. No. 5,437,421.
There remains a need, however, to more favorably alter the characteristics of the boundary layer than has heretofore been achieved. That is, there remains a need to optimally alter or affect the boundary characteristics in a way that most significantly reduces the drag of the fluid as it passes over the body.
SUMMARY OF THE INVENTION
The present invention addresses the above and other needs by using magnetic and electric fields in a controlled manner so as to create Lorentz forces that affect the flow of a conductive fluid near the boundary layer of a control tile, or a matrix of control tiles, immersed in a conductive fluid. More specifically, the Lorentz forces created by the invention combine to form a vortex wavefront transverse to the fluid flow direction, which vortex wavefront advantageously reduces drag of the conductive fluid over the matrix of control tiles. When such matrix of control tiles is formed or mounted on a surface immersed within a conductive fluid, the invention may thus be used to render movement of such surface through such conductive fluid more efficient, i.e., with less drag.
The control tiles used with the invention are combined to form control cells, with each control cell including a pair of electrodes and at least one permanent magnet. The pair of electrodes are coupled to a current source which biases the electrodes to cause an electrical current to flow from a positive electrode (anode), through the conductive fluid in which the cell electrodes are immersed, to a negative electrode (cathode). The current source is time multiplexed to better control the direction of the current flow between adjacent electrodes. The permanent magnet(s) generates a magnetic field which interacts with the electrical current to create a Lorentz force that influences the flow of the conductive fluid, near the boundary of the control tile, e.g., reduces drag of the fluid as it flows over the tile surface.
A primary application of the invention is to place or form such control tiles or cells within the hull of an ocean-going ship, thereby reducing the drag of the sea water passing over the surface of the hull, thereby making movement of the ocean-going ship through the sea water more efficient. It is to be emphasized, however, that the invention is not limited to use only within the hull of a ship. Rather, the invention may be used for any application where a surface must be moved or propelled within a conductive fluid, and where such conductive "fluid" may comprise either a liquid or a gas. Thus, for example, the invention could also be used within or on the shell surface of an aircraft, e.g., a space shuttle craft or an airplane, where such aircraft must pass through an ionically-charged atmosphere.
It is also important to note that drag reduction, such as is achieved with the present invention, facilitates a more stealthy movement through the medium because decreased turbulence produces less acoustic emission from the vessel or aircraft. Hence, the present invention may advantageously be used to make it more difficult for enemies to detect a submarine or other vessel moving through sea water.
There are many other uses and applications for the drag reduction achieved by the invention, in addition to those enumerated above. For example, a reduction in drag through use of the present invention may be used to improve the flow of conductive fluids through a pipe. The invention may also be used to increase drag in order to achieve enhanced braking of ocean going vessels, or of aircraft or spacecraft traveling through an ionized medium. Additionally, decreased or increased drag (achieved through use of the invention) provides an effective way to achieve rudderless steering of ocean-going vessels, or of aircraft or spacecraft that travel through an ionized medium. Indeed, there are many applications for the present invention. Any application where a reduced fluid drag, or a controlled fluid drag, is required or desired, may benefit from the invention.
One embodiment of the invention may be characterized as an apparatus or method for controlling the flow of a conductive fluid over a control surface immersible within the conductive fluid. Such apparatus or method includes means for propelling the control surface through the conductive fluid; and means for electromagnetically generating at least one vortex wavefront on the control surface that passes over the control surface as the control surface moves through the conductive fluid. It is this vortex wavefront that reduces the drag associated with the flow of the conductive fluid over the control surface. In accordance with one aspect of the invention, the vortex wavefront is formed at right angles to the direction of fluid flow over the control surface.
Another embodiment of the invention may be similarly characterized as an apparatus for controlling the flow of a conductive fluid over a control surface. In broad terms, such apparatus includes a matrix of electrodes spread over the control surface. Further included is a means for biasing selected electrodes in pairs so that two of the electrodes within the matrix of electrodes function as an electrode pair, with each electrode pair having an anode electrode and a cathode electrode. This arrangement allows an electrical current to flow from the anode electrode of each electrode pair through the conductive fluid to the cathode electrode of the electrode pair. There is also included a means for generating a magnetic field having magnetic flux lines that are transverse to the electrical current flowing through the conductive fluid. The combination of the electrical current and the magnetic flux cause a Lorentz force to be created that is transverse to both the electrical current and magnetic flux lines. This Lorentz force affects the flow of the conductive fluid over the control surface. More specifically, the biasing means includes time multiplexing means for time multiplexing the electrical current to assure a desired sourcing/sinking relationship of the electrical current: between selected electrode pairs exists so that a coordinated pattern of Lorentz forces is created that affects the flow of the conductive fluid over the control surface in a desired manner, e.g., to reduce drag.
In accordance with an important aspect of the invention, the time multiplexing means forces electrical current sourced from one anode electrode to be sunk at a desired adjacent cathode electrode and not at a non-desired adjacent cathode electrode. Carefully controlling which electrodes source and sink current in this manner through the use of the time multiplexing means advantageously allows the induced Lorentz forces to create a vortex wavefront that is at a desired angle, e.g., transverse, relative to the direction of fluid flow over the control surface. It is this vortex wavefront that is primarily responsible for reducing the drag associated with the fluid flow over the control surface.
It is a feature of the invention to provide beneficial control of fluid motion over a surface, e.g., to reduce drag as a conductive fluid flows over the surface.
It is another feature of the invention to provide a time-multiplexed current driver for use with a matrix of electrodes on a control surface immersible in a conductive fluid which, in combination with a magnetic field, steers resulting Lorentz forces for beneficial purposes. More particularly, it is a feature of the invention to provide such Lorentz forces so as to create a vortex wavefront that significantly reduces drag as the conductive fluid passes over the control surface.
It is yet another feature of the invention to provide a control surface, immersible in a conductive fluid such as seawater, which when electromagnetically energized, exhibits a reduced drag as such surface moves through the conductive fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
FIG. 1A shows a plan view of a conventional single cell fluid control device;
FIG. 1B shows a sectional view of the control device of FIG. 1A taken along the line 1B--1B;
FIG. 2A illustrates a plan view of a simplified representation of a single-cell fluid control device having a force vector L centered in the cell and oriented in the -y direction;
FIG. 2B is a sectional view of the simplified cell of FIG. 2A taken along the line 2B--2B, and illustrates the vortexes that are created in a fluid layer above the cell in the presence of such vector L;
FIG. 2C is a plan view of adjacent cells as in FIG. 2A, and further illustrates the regions where the vortexes cancel and add in the presence of a central vectors L;
FIG. 2D illustrates a panel formed of fluid control cell devices like that shown in FIG. 2A, and conceptually illustrates how one or more roller vortexes ("rollers") are created when aligned vector Lorentz forces L are applied to the cells, with the rollers having a wavefront that parallels the alignment axis;
FIG. 2E depicts a panel formed of fluid control cell devices in accordance with the present invention being propelled through a conductive fluid;
FIG. 3A shows a plan view of one type of basic control cell that may be used with the present invention;
FIG. 3B shows a side view of the basic control cell shown in FIG. 3A;
FIG. 3C shows an electromagnetic turbulence control (EMTC) panel made up of the basic cells shown in FIGS. 3A and 3B, and illustrates how, for unperturbed flow from left to right, an outwardly directed Lorentz force (shown as circles with dots inside) is created at each energized cell, which forces create roller wavefronts that parallel the dotted lines;
FIG. 3D illustrates one type of pulsing that may be applied to energize the electrode pairs;
FIG. 4A is a simplified circuit diagram that illustrates ho unwanted currents may be created when only a single current driver is used;
FIG. 4B shows the use of two multiplexed current drivers in accordance with the present invention in order avoid the unwanted currents of FIG. 4A;
FIG. 4C illustrates the use of a single current driver switched by a multiplex control circuit to create two isolated current drivers;
FIG. 5 is a timing waveform diagram that illustrates the concept of current multiplexing in accordance with the present invention; and
FIG. 6 shows a plan view of an EMTC panel made in accordance with the invention wherein two multiplexed current drivers, labeled a and b are used.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims.
To better understand and appreciate the present invention, it will first be beneficial to have a basic understanding of how fluid control has been attempted in the prior art. Some basic teachings relative to the prior art were presented above in the Background portion of this application. Additional detail concerning the prior art technique for fluid flow control is illustrated in FIGS. 1A and 1B. FIG. 1A shows a plan view of a single cell fluid control device made in accordance with the teachings of the prior art, and FIG. 1B shows a sectional view of the prior art control device of FIG. 1A taken along the line 1B--1B. The single cell device is formed on a suitable panel or substrate 12. Such panel 12 is designed to be exposed to fluid flow, represented in FIGS. 1A and 1B by the double arrow 14. That is, as drawn in FIGS. 1A and 1B, it is contemplated that fluid will flow over the panel 12 from left to right.
A first pair of electrodes 16, 18 is placed on a top surface (the surface exposed to the fluid flow) of the panel 12. The electrode 16 is electrically connected to the positive side of a voltage source 20, and the electrode 18 is electrically connected to the negative side of the voltage source 20. Thus, in the presence of a conductive fluid, an electric current, J, represented in the figures by the vector arrows 22, will thus flow from the positive electrode 16 to the negative electrode 18.
Positioned behind the panel 12 are a pair of permanent magnets 24 and 26. (These magnets 24 and 26 have been omitted from FIG. 1B for clarity.) The south pole S of the magnet 24 is positioned closest to the back side of the panel 12, while the north pole N is likewise positioned closest to the back side of the panel 12. A magnetic field, B, is thus established by the presence of the magnets 24 and 26. This magnetic field B has a polarity (direction) as illustrated by the vector arrows 28 in FIGS. 1A and 1B. Note that in FIG. 1B, the magnetic field B points into the paper, and thus the vector arrows 28 representing the magnetic field B are illustrated by the symbol x (an "x" within a circle, which is symbolic of looking at the back end of an arrow). If a vector arrow were pointing out of the plane of the paper, it would be represented by the symbol • (a dot within a circle, symbolic of looking at the front end of an arrow).
As is evident from FIGS. 1A and 1B, the electric current J and the magnetic field B are established so as to be substantially transverse (perpendicular) to each other. As is known in the art, whenever an electric current J is acted upon by a magnetic field B, a Lorentz force, L, is established that is perpendicular to both the current J and the magnetic field B. This Lorentz force L is represented in FIGS. 1A and 1B by the vector arrows 30. As seen in FIG. 1A, the vector arrows 30 representing the Lorentz Force L are directed into the plane of the paper, and are thus represented by the symbol x; while in FIG. 1B, the Lorentz Force is directed downward (in the "y" direction, of the x-y-z coordinate system illustrated in FIGS. 1A and 1B), toward the panel 12.
Turning next to FIGS. 2A, 2B, 2C, 2D and 2E, there is shown a sequence of diagrams that illustrate the effect the Lorentz force, L, also referred to herein as a force vector L, has on a fluid that passes over the surface of cell, or matrix of cells, wherein the Lorentz force L is present. FIG. 2A illustrates a plan view of a simplified representation of a single-cell fluid control device having a force vector L centered in the cell and oriented in the -y direction (into the plane of the paper); while FIG. 2B shows a sectional view of the simplified cell of FIG. 2A taken along the line 2B--2B. As seen in these two figures, the force vector L tends to create a vortex (or whirling pattern) 34 in a fluid layer 32 above the cell.
For a single cell device, the vortexes 34 are generally created around the force vector L, as though the force vector L were pushing the fluid layer 34 down into the surface in the center of the cell, with the fluid whirling out away from the center point, as seen best in FIG. 2B. When two such cells are positioned adjacent each other, as shown in FIG. 2C, then the whirling motion established within the fluid layer 32 tends to cancel in the region between the adjacent cells, i.e., in the region 36 in FIG. 2C, while it tends to be reinforcing in the region 38 on each side of the center force vector L. The net result is that a plurality of force vectors L, applied along a line 39 to adjacent aligned cells arranged in a matrix 42 of cells, as seen in FIG. 2D, establish a wavefront 40 of turbulent fluid motion, or a vortex wavefront 40, along either side of the force vector line 39, i.e., on either side of the force vectors L. Such wavefront 40 may then be selectively moved along the surface of the matrix 42 by controlling the location where the current vector J is allowed to interact with the magnetic vector B.
Advantageously, a panel or matrix 42 of fluid control cell devices formed in accordance with the present invention, when propelled through a conductive fluid by a suitable propulsion means 44, and when the vortex wavefronts 40 are properly controlled, allows the friction or drag associated with the flow of the conductive fluid over the matrix to be significantly reduced. Thus, as illustrated in FIG. 2E, if the matrix 42 of control cell devices is attached to, or made an integral part of, a vessel structure, e.g., the hull of an ocean-going ship, it is possible, through selective control of the current vectors J which are imposed on the surface of the matrix, to create vortex wavefronts which reduce the drag of the hull as it cuts through the conductive sea water, thereby reducing the amount of energy required to move the vessel through the sea water. Here, and elsewhere throughout this application, the term "control cell device" refers to the electrodes, voltage source, panel or substrate, and magnets used to create a vector force L, when such control cell device is immersed in a conductive fluid.
Turning next to FIGS. 3A and 3B, there is shown one type of basic control cell device that may be made in accordance with the invention. FIG. 3A shows a plan view of one such basic control cell device; and FIG. 3B shows a side view of the basic control cell shown in FIG. 3A. As seen in these figures, electrodes 50 and 52 are energized with a suitable power source (not shown in these figures) so that electrode 50 is positive relative to electrode 52, thereby creating an electric field between the electrodes which causes an electric current to flow from electrode 50 to electrode 52. The flow of such current is represented by the current vector J.
Still with reference to FIGS. 3A and 3B, it is seen that three magnets, 54, 55, and 56, are positioned and polarized so as to create a magnetic field B in the region above the electrodes 50 and 52. Thus, when the electrodes 50 and 52 are immersed within a conductive fluid, so as to create the current vector J, the current vector J reacts with the magnetic field B so as to create the force vector L .
Next, with reference to the planar view of FIG. 3C, an example is shown of how individual control cells, as shown in FIGS. 3A and 3B, may be arranged in a matrix 60 in order to create a vortex wavefront. In the matrix 60 illustrated in FIG. 3C, elongate magnets 61, 62, 64, 66, 68 and 70 form a boundary between adjacent columns of control cells. Five columns of electrodes are shown, by way of example. Each column of control cells, includes eight electrodes, or four pairs of control cells. In the left column, for example, a first pair of electrodes 52a and 50a is energized so that a force vector 58a is created that points away from the plane of the paper. The second and fourth pair of electrodes in the left column are not energized, while the third pair of electrodes 50a', 52a' is energized, creating a force ector 58a'.
The electrodes in the right (5 th ) and middle (3 rd ) columns of the matrix 60 are energized in the same manner as are the electrodes in the left column. The electrodes in the second and fourth columns, on the other hand, are energized such that the second and fourth pair of electrodes are energized, while the first and third pair of electrodes are not energized.
Still referring to FIG. 3C, it is seen that each pair of energized electrodes allows a force vector L, pointing out of the paper, to be created. In combination, the energization of the electrode pairs shown in FIG. 3C, and the resulting force vectors L, creates a vortex wavefront aligned with the lines 72, 74 and 76.
The voltage applied to the electrodes in FIG. 3C is pulses as shown in FIG. 3D. As seen in FIG. 3D, the pulse period T is such that L˜VT, where L is the distance between vortex wavefronts (shown in FIG. 3C) and v is the flow speed. The first application of the pulse sets up a set of propagating vortex wavefronts as shown in FIG. 3C. The voltage is then turned off and the wavefronts drift with the flow velocity (to the right in FIG. 3C). The vortex wavefronts have traveled a distance L when another pulse is applied to the electrodes. This pulse acts to constructively add to the existing flow of the vortex. In this way, the pulsing resonantly grows and maintains the strength of the vortices.
Various techniques may be used to construct the matrix panel 60, or other panels useful with the invention. Reference is made, for example, to U.S. patent application Ser. No. 09/100,307, filed on Jun. 19, 1998 assigned to the same assignee as is the present application, which application is incorporated hereby by reference.
As seen in FIG. 3C, the vortex wavefronts created are oblique (e.g., diagonal) with the fluid flow direction, illustrated by the arrow 78. Such an oblique wavefront may not be optimum for reducing fluid drag. Optimal reduction of fluid drag is produced with vortex wavefronts that are perpendicular to the unperturbed flow direction. For drag reduction, it is important that the tangential velocity produced by the vortex be parallel to the flow; and only the component along the flow direction contributes to the drag reduction effect. Thus, oblique vortex wavefronts are not efficiently used. A more optimum wavefront would be one that has the tangential velocity parallel with the fluid flow direction, i.e., one wherein the vortex wavefronts are oriented perpendicular to the unperturbed fluid flow.
An additional disadvantage of the energization scheme shown in FIGS. 3A-3D is that the distance between force locations along the vortex wavefront is large. This causes the wavefront not to be as well formed as it might otherwise-be if the force locations could be closer together.
Yet a further shortcoming associated with the energization scheme of FIGS. 3A-3D relates to the positioning of the magnets. That is, as seen in FIG. 3B, the normal component of the Lorentz force L is largest where the magnetic field is weakest. At the position of the maximum magnetic field on the surface of the magnet, no useful force is obtained. Thus, the magnetic force is not employed in a very efficient manner.
Moreover, it should be noted that most structures of a vessel designed to be propelled through a conductive fluid (e.g., vessels that would be used with the present invention) would employ, in one form or another, a curved surface or panel of some type, e.g., a cylindrical shape. Thus, it would be necessary to employ the matrix of cells shown in FIG. 3C on a curved panel. This would, in turn, require the use of curved magnets. Disadvantageously, curved magnets are more expensive than non-curved magnets. Also, in order to increase the magnetic field over the center of a tile or cell, a third magnet is used. Such third magnet causes complications in the magnet assembly.
In order to address the above concerns associated with the embodiment of the invention shown in FIGS. 3A-3C, i.e., in order to create a vortex wavefront that moves in the same direction as the fluid flow, and thereby reduce the drag associated with the fluid flow a maximum amount; and in order to also increase the density of the force centers, a preferred embodiment of the present invention utilizes a current multiplexing scheme to selectively energize only certain ones of the electrodes at the same time. Such multiplexing scheme advantageously assures a vortex wavefront that has tangential velocity components parallel to the fluid flow, and thus reduces drag associated with the flow of the fluid over the panel where the control cells are utilized i.e., a vortex wavefront is produced which propogates in a direction substantially parallel to the fluid flow, for example, as referred to in the discussions concerning FIG. 6.
To illustrate the need for current multiplexing, reference is made to FIG. 4A, which is a simplified circuit diagram that illustrates how unwanted currents may be created when only a single current driver is used. That is, as seen in FIG. 4A, if electrode pair 78 is energized at the same time as is adjacent electrode pair 80, some unwanted current 82 flows between the positive electrode of pair 78 and the negative electrode of pair 80. This unwanted current creates a force vector L that opposes the force vectors L created by the wanted currents, and is thus counterproductive to the formation of the desired vortex wavefront.
To overcome the problem of unwanted current between adjacent electrode pairs, the present invention multiplexes the energization of the electrode pairs such that adjacent electrode pairs are not energized at the same time. Such multiplexing is illustrated in FIG. 4B As seen in FIG. 4B, the first pair of electrodes 78 is energized with a first current driver 79, and the second pair of electrodes 80 is energized with a second current driver 81. While only two current sources are shown in FIG. 4B, for illustration, it is to be understood that n current sources could be used, where n is an integer, depending upon the number of phases that are desired.
The timing relationship between the current drivers 79 and 81 is illustrated in FIG. 5. As seen in FIG. 5, the current driver 79 for the electrode pair 78 is never on at the same time as is the current driver 81 for the electrode pair 80. The net result is that unwanted currents do not flow between adjacent electrode pairs.
As further seen in FIG. 5, the current drivers 78 and 80 each include a burst of square waves, each having a period τ. In FIG. 5, five such cycles of square waves are shown, comprising a first portion 82 of the current driver waveform, followed by a second portion 83 of the waveform wherein no signal is present. The period T of the envelope of the driver pulses, comprising the first and second portions, is determined by the resonant velocity required to grow the vortex wavefronts. The value of T is determined by the unperturbed flow velocity. By way of example, for a tile column spacing of 1.08 cm, and a flow velocity of about 10 m/sec, the corresponding period T is on the order of about one millisecond. It may also be an integral multiple of this time. For a two phase system, as shown in FIG. 5, each burst of pulses must fit within T/2, or approximately 500 μsec (microseconds). The minimum value of τ is about three times the shortest attainable risetime. The value of τ could, of course, be greater. In one exemplary embodiment, τ is on the order of about 5 μsec.
An alternate multiplexing scheme, using a single current driver 90, is depicted in FIG. 4C. In FIG. 4C, the first pair of electrodes 78 is connected to the current driver 90 through switches 92 and 94. The connection is established so as to create a desired polarity between the electrodes of the pair 78. At the appropriate time, the switches 92 and 94 are switched, by multiplex control circuitry 96, so as to connect the current driver to the electrode pair 80. In this manner, only one electrode pair, 78 or 80, is allowed to energized at the same time.
Clearly, variations of the multiplexing schemes illustrated in FIGS. 4B and 4C and FIG. 5 are evident to those of skill in the art. The important criteria is that adjacent electrode pairs not be energized at the same time, and that the movement of the vortex wavefront be timed so as to match, approximately, the flow velocity of the conductive fluid. As indicated above, for example, for an n phase system, n different current sources could be employed, where n is an integer. By way of illustration, in one embodiment of the invention, eight (n=8) different current sources are used.
To illustrate operation of an eight phase system (n=8), reference is again made to FIG. 3C, which figure assumes five columns of eight electrodes each. During a first phase, or during a first portion of time that represents 1/8 of an energization cycle, the electrodes are energized as shown in FIG. 3C, i.e., the 1st and 3rd electrode pairs are energized in the 1st, 3rd, and 5th columns, while the 2d and 4th electrode pairs are energized in the 2d and 4th columns. Such energization pattern advantageously results in the vortex wavefronts along the lines 72, 74 and 76.
During a second portion of the energization cycle, which again represents 1/8 of the energization period, the pattern shown in FIG. 3C shifts up one electrode in each column of electrodes. That is, electrodes 52a and 52a' become the anodes of their respective electrode pairs, while electrodes 50a and 50a' are turned off, and with the electrodes immediately above 52a and 52a' becoming the cathodes. (Note, for purposes of FIG. 3C, the columns of electrodes are considered continuous, so that the electrode above electrode 52a is the electrode at the bottom of the column.) During a third portion of the energization cycle, which also represents 1/8 of the energization period or cycle, the electrodes immediately above electrodes 52a and 52a' become the anodes of their respective electrode pairs, while electrodes 52a and 52a' are turned off, and with the electrodes immediately below 50a and 50a' becoming the cathodes.
The above-described process continues, with the energization pattern of the column shifting up one electrode during each phase, or 1/8, of the energization cycle. Thus, after shifting up eight electrodes, or after one cycle, the energization pattern returns back to that shown in FIG. 3C. The net effect is that the vortex wavefronts 72, 74 and 76, for the pattern shown in FIG. 3C, propagate to the right, in the same direction as the flow arrow 78.
It is to be understood that an n phase system could also be implemented using n separate current or voltage sources, e.g., as shown in FIG. 4B for a two phase system; or through use of a single current or voltage source which is shared between n different pairs of electrodes, as taught in FIG. 4C.
By using two multiplexed currents drivers as shown in FIG. 4B, or an equivalent circuit, a driving pattern as illustrated in FIG. 6 may be obtained. As seen in FIG. 6, adjacent columns are not energized at the same instant of time. That is, as shown in FIG. 6, only the 1 st , 3 rd , and 5 th columns of electrodes are energized, while the 2 nd and 4 th columns remain unenergized. Thus, no unwanted current flow is possible between electrode pairs of adjacent columns. Further, within the energized columns, the first and third electrode pairs are energized with one phase, e.g., the "a" phase; and the second and fourth electrode pairs are energized with a different phase, e.g., the "b" phase. The "a" and "b" phases are controlled so as to be as shown in FIG. 5, or equivalent, so that no adjacent electrode pairs are ever energized at the same time. Thus, no unwanted current flow is possible between adjacent electrode pairs within the same column. As a result, a vortex wavefront 98 is; created that is aligned with the fluid flow, i.e., the wavefronts 98 move in substantially the same direction as the fluid flow direction 78.
While not specifically shown in FIG. 6, it is to be understood that the 2 nd and 4 th columns of electrodes are similarly energized with a two phase signal at the same time that the 1 st , 3 rd , and 5 th columns of electrodes are not energized. This pattern of alternate column energization is what moves the resulting vortex wavefront along in the same direction as the fluid flow.
Additional phases and columns could also be used, as required, to best match the fluid flow. For example, a driving signal could be applied sequentially to energize three adjacent columns, with only one of the three columns being energized at a given time, and with the driving signal phased so that adjacent electrode pairs within the energized column are not energized at the same time.
A key consideration when using current multiplexing is to quickly change the force pattern (i.e., change the electrode pair that is energized) while the vortex wavefront is above the active cells. That is, the multiplexing time scale must be short compared to the dwell time of the vortex wavefront above the energized cells. Then, the wavefront is hit by a rapid succession of uniformly distributed impulses while it is essentially in one position. As a result, the average force given to the vortex wavefront, which may be conceptually visualized as a "roller" that rolls along the surface of the panel or structure on which the cells are located, is uniformly applied with closely spaced force centers.
As described above, it is thus seen that the present invention provides beneficial control of fluid motion over a surface, e.g., to reduce drag as a conductive fluid flows over the surface. More particularly, it is seen that through the use of a time-multiplexed current driver, Lorentz forces may be selectively created so as to establish a vortex wavefront, or "roller", having tangential velocity components that significantly reduce the drag associated with the flow of a conductive fluid over the control surface.
While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. | Magnetic and electric fields are used in a controlled manner to create Lorentz forces that affect the flow of a conductive fluid near the boundary layer of a control tile, or a matrix of control tiles, immersed in a conductive fluid. The control tiles are combined to form control cells, with each control cell including a pair of electrodes and at least one permanent magnet. The pair of electrodes are coupled to a current source which biases the electrodes to cause an electrical current to flow from a positive electrode (anode), through the conductive fluid in which the cell electrodes are immersed, to a negative electrode (cathode). The current source is time multiplexed to better control the direction of the current flow between adjacent electrodes. The permanent magnet(s) generates a magnetic field which interacts with the electrical current to create a Lorentz force that influences the flow of the conductive fluid, near the boundary of the control tile, e.g., reduces drag of the fluid as it flows over the tile surface. The invention may be used, e.g., within the hull of an ocean-going ship to locally or globally reduce or increase the drag of the sea water passing over the surface of the hull. | 1 |
This invention relates to a method for purifying hemoglobin and methemoglobin, which are collectively referred to herein as hemoproteins. The term "hemoproteins" as used herein is intended to be restricted to hemoglobin and methemoglobin. More particularly, the invention provides a method for economically separating hemoglobin from other proteins on a large scale. The method employs the techniques of bioselective elution, wherein the hemoglobin and protein mixture is adsorbed to an ion exchange matrix and hemoglobin is selectively eluted using a biospecific ligand.
It has long been desired to have a hemoglobin-based blood substitute or "synthetic blood", which would be cheaply and plentifully available. Recently, synthetic bloods of various compositions have been produced and have been shown to be suitable substitutes for whole cellular blood in a wide range of applications.
Replacement of blood is most often used to maintain the circulation volume of the blood fluid and to provide the blood volume with sufficient oxygen transport capacity to meet the requirements of cellular respiration in the organism. In maintaining circulation volume, it is essential that the fluid medium have dissolved macromolecules which will maintain the osmotic pressure of the medium. These requirements are readily met by present day blood replacement practices; however, supplies of human blood for replacement purposes is dependent on donation by healthy individuals, and there are continual problems associated with storing, processing and typing donated blood.
Synthetic blood has the advantages of being sterile, being compatible with all blood types, and having a long shelf life. If synthetic blood can be made economically, a constant supply would become available, which would not be dependent on blood donations.
The development of synthetic blood followed from the finding that stroma-free hemoglobin solutions embody many of the attributes of an ideal blood substitute; however, because of its small size, hemoglobin is too rapidly excreted through the kidneys, necessitating replenishment at short intervals. A number of approaches have been developed to slow down the excretion of hemoglobin in a synthetic blood, including crosslinking the four globin subunits of hemoglobin, polymerising the hemoglobin, conjugating the hemoglobin to a carrier molecule such as dextran or polyethyleneglycol, or encapsulating the hemoglobin within liposomes. The different types of hemoglobin-based blood substitutes so obtained are capable of delivering oxygen to tissues, and exhibit plasma halflives from several hours to two days. Their syntheses all require hemoglobin, usually human, as starting material, which is presently obtainable from outdated blood from bloodbanks.
Normal human hemoglobin is a tetramer consisting of two alpha and two beta globin chains, each chain containing a heme group. Hemoglobin is a member of a family of related hemoproteins, with methemoglobin being another significant member. Human fetal hemoglobin consists of two alpha and two gamma globin chains. The present invention is useful for purifying hemoproteins generally, but for the purpose of manufacturing synthetic blood, the inventive method is particularly important in the purification of human adult hemoglobin.
With the advent and rapid development of recombinant DNA technologies, the prospect of economically obtaining human globins from cultured microorganisms or cells has become more promising. An important limiting factor in terms of cost in the synthesis of globins by way of recombinant DNA resides in the need to separate the alpha and beta globins from host proteins, to assemble two alpha and two beta chains into a tetramer, to insert a heme molecule (most likely in the form of hemin) into each globin chain at an appropriate stage, and to reduce the hemin groups in the tetramer from the ferric to the ferrous form, i.e. from methemoglobin to hemoglobin. Methods that facilitate such downstream processing of the globins into purified, functional hemoglobin, therefore, become crucial to the economic feasibility of hemoglobin production using recombinant DNA. These methods would also be useful for obtaining purified hemoglobin from outdated blood, since unwanted proteins in addition to hemoglobin are released upon the lysis of erythrocytes.
The present invention utilizes the principles of biospecific or bioselective elution to achieve a rapid, simple purification of hemoglobin and related hemoproteins from other proteins. When exposed to air, hemoglobin readily binds oxygen, and in its oxygenated form is properly termed (oxy)hemoglobin. However, as used herein the term "hemoglobin" is intended to include hemoglobin in its oxygenated and deoxygenated forms, and it will be apparent to the skilled person which form of hemoglobin is being referred to from the context in which the term is used.
Prior to the present invention, affinity chromatography has been used to separate hemoglobin from other proteins. In 1982 K. Tsutsui and G. C. Mueller described the use of hemin-agarose to purify heme-binding proteins, including globin (Analytical Biochemistry, 121, 244-250). J. C. Hsia and S. S. Er described the use of ATP-agarose for the affinity chromatographic purification of hemoglobin (J. Chromatography, 374, 143-8 (1986); International patent applications WO87/00177 and WO87/04169). These prior known purification methods require the preparation of biospecific chromatographic matrices. For example, a ligand, such as ATP, which is biospecific to hemoglobin under anticipated chromatography conditions, is attached to an agarose matrix, and the hemoglobin-containing mixture is contacted with the matrix, the hemoglobin selectively being bound to the ATP ligand. While biospecific chromatographic matrices are useful for purifying hemoglobin on a small scale, they are very expensive due to the need to custom synthesize the specialized matrices containing a covalently bonded ligand, and hence, are not suitable for large scale commercial purifications.
The present invention utilizes inexpensive, readily available conventional anionic or cationic exchange matrices and provides a low cost means for achieving large scale purification of hemoglobin. Cost effectiveness is particularly important in relation to the manufacture of hemoglobin since, in contrast to most other synthetic proteins used for medical purposes, gram quantities of the protein, e.g. 30g, are needed to provide a clinically useful dose of a hemoglobin-based blood substitute. Thus, the present invention based on the principles of biospecific elution provides a solution to the problem of developing an economic method for purifying hemoglobin. Additionally, the invention enables the added benefit of combining hemin reduction with the purification of the protein.
The principles of bioselective elution have been known for some time (see, for example, B. M. Pogell (1962), Biochem. Biophys. Res. Commun. 7, 225; and (1966), in Methods in Enzymology (W. A. Wood, ed) 9, 9). Prior to this invention, hemoglobin purification has favoured affinity chromatography possibly on the reasoning that when dealing with a complex mixture of proteins, it is only the resolving power of affinity chromatography which holds out a reasonable prospect for achieving a clean one step purification. A standard method for purifying hemoglobin from red cell extracts involves adsorption on a DEAE (diethylaminoethyl) matrix at near neutral pH (L. C. Cheung et al (1984) Anal. Biochem., 137, 481). While this method is suitable for red cell extracts, it may result in hemoglobin with a phospholipid contaminant which has been shown to give an adverse reaction in at least some animals.
Importantly, however, this standard purification technique is not suited to the purification of hemoproteins mixed with the diverse proteins expected in the production of hemoproteins by recombinant DNA procedures.
Since bioselective elution utilizes standard ion exchange resins, a skilled person might suppose that this purification technique did not possess sufficient resolving power to provide a clean separation of hemoglobin from a protein mixture which, when the hemoglobin is made using DNA recombinant technology, would contain a plurality of diverse proteins. The present invention provides the unexpected result that hemoglobin and methemoglobin can be acceptably purified from a mixture of diverse proteins using bioselective elution on standard anionic or cationic exchange matrices. Additionally, the invention includes the method of reduction of methemoglobin to hemoglobin while adsorbed on the ion exchange matrix followed by selective elution of the resultant hemoglobin in a pure form.
Accordingly, the present invention provides a method for purifying a hemoprotein mixed with other proteins, comprising contacting the protein mixture with an ion exchange matrix so that the hemoprotein component of the mixture is adsorbed to the matrix. The matrix is then washed to remove unadsorbed components, and the hemoprotein is selectively eluted from the matrix using a ligand which specifically binds to the hemoprotein causing it to desorb from the matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-10 are polyacrylamide gel electrophoresis (PAGE) chromatograms showing elution fractions as described in the examples, infra.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Synthesis of hemoglobin using recombinant DNA methods will enable the production of the alpha and beta globin subunits by the insertion of the genes coding for these globins into the genome of a host cell. The host cell may be E.coli, a yeast, a cultured mammalian cell or some other suitable host. Methods are known for the assembly of the methemoglobin tetramer, comprising two alpha and two beta globins, with four hemin groups, but undoubtedly additional work will be required to provide optimum yields for the commercial product.
Purification of the assembled methemoglobin would involve separation from contaminating proteins derived from E.coli, yeast supernatant proteins or, in the case of mammalian cell cultures, calf serum proteins. The effectiveness of the present invention is demonstrated by the examples, infra, which also include separation of hemoglobin or methemoglobin from human serum proteins and snake venom proteins.
In biospecific elution, a protein is allowed to adsorb to an ion exchange matrix, along with other proteins of comparable electric charge configuration. A ligand that binds specifically to the target protein is then added. In binding the ligand, the protein undergoes a change in its conformation, thereby altering the strength of its interaction with the matrix. Often the specific ligand carries a net charge which would result in a change in the net charge of the protein upon binding with the ligand; also altering the strength of protein interaction with the matrix. When the conformation or net charge change or both induced by the ligand results in a weakening of the protein-matrix interactions, it leads to a specific elution of the target protein, while other proteins which do not bind the ligand remain adsorbed to the matrix. Most often, a negatively charged ligand is allowed to bind to a target protein and induce its elution from a cation exchange matrix.
Hemoglobin is known to readily bind a large number of polyanionic ligands such as polyphosphates, e.g., pyrophosphate, inositol--tri, tetra, penta or hexaphosphate, ATP, ADP, 2,3-diphosphoglycerate (DPG), etc.; polycarboxylates and polysulfates, to name a few. In the present invention, the use of polyphosphates is preferred, with pyrophosphate and phytate being most preferred. A problem faced in the development of the present method was to discover those conditions where the ligand binding to hemoglobin will result in a biospecific elution of hemoglobin from an inexpensive, commercially available ion exchange matrix. The separation conditions must not be so extreme as to denature the hemoglobin. For example, the pH range should be from 4.0 to 11.0, and preferably from 5.0 to 9.5. Using the foregoing factors, biospecific elution was initially carried out using cation exchange matrices in association with pyrophosphate and phytate (inositol-hexakisphosphate) as the ligands. As shown by the examples which follow, surprisingly clean results were obtained using phosphocellulose, sulfopropyl-SEPHADEX (trade mark, Sephadex is a cross-linked dextran polysaccharide) and carboxymethyl-SEPHADEX, all of which are standard commercially available cation exchange resins. Cation exchange resins of these types are herein generically termed phospho-, sulfo- and carboxymethylpolysaccharide matrices. Surprisingly, biospecific elution of hemoglobin using pyrophosphate or phytate as the ligand also effected separation in association with conventional anion exchange resins such as DEAE-SEPHADEX (poly[2-(diethylamino)ethyl] polyglycerylene dextran hydrochloride), which is herein generally termed diethylaminoethylpolysaccharide.
The present invention also provides a method for reduction of the hemin groups in methemoglobin from the ferric to the ferrous oxidation state in combination with the biospecific elution purification. Thus, methemoglobin is adsorbed to an ion exchange matrix and washed with a reducing agent such as sodium dithionite. The resulting hemoglobin is then selectively eluted in the usual way to give the purified substance. This method for reducing methemoglobin has the advantage of minimizing the dithionite/hemoprotein contact time so that side reactions are greatly reduced as compared with solution methods.
The invention is particularly described with reference to the following examples which are provided for illustration and not to limit the scope of the invention.
EXAMPLE 1
Phosphocellulose-pyrophosphate
0.1 ml of 6% human hemoglobin in the form of a red blood cell lysate (after centrifugation to remove cell membranes) is mixed with 0.2 ml of an extraneous protein solution and 0.3 ml of 0.2 M sodium acetate buffer, pH 6.0. The mixture is placed on a column (1 cm diameter x 6 cm height) of phosphocellulose (Whatman Co., grade P11) equilibrated with the same 0.2 M sodium acetate buffer pH 6.0. The column is developed with 3x bed volumes each of successively:
(a) full strength 0.2 M sodium acetate buffer, pH 6.0, to wash away unadsorbed and lightly adsorbed, proteins;
(b) 0.01 M-0.02 M sodium pyrophosphate/0.02 M sodium acetate, pH 6.0, which elutes some hemoglobin, and also some lightly adsorbed proteins;
(c) 0.04 M sodium pyrophosphate/0.02 M sodium acetate, pH 6.0, which desorbs the hemoglobin.
FIG. 1 shows the electrophoresis results of the method of Ex. 1 starting with 0.1 ml of 6% hemoglobin and 0.2 ml of an extract of E.coli proteins prepared by extracting for 30 min. 0.1 g of an E.coli acetone powder with 2 ml of 0.2 M sodium acetate, pH 6.0, and removing insolubles by centrifugation. Lane a shows the mixture of hemoglobin and E.coli proteins. Lanes b and c are fractions eluted by 0.2 M sodium acetate buffer. Lane d is a fraction eluted by 0.01 M pyrophosphate. Lane e is control hemoglobin as a reference, and lane f shows purified hemoglobin eluted from the ion exchange matrix by 0.04 M pyrophosphate. Note that the reference sample of control hemoglobin contained an extra protein band compared to the purified hemoglobin in lane f. This is because the control hemoglobin was actually a red blood cell lysate, which contained other red cell proteins besides hemoglobin.
FIG. 2 shows the electrophoresis results of the method of Ex. 1 starting with 0.1 ml 6% hemoglobin and 0.2 ml of the macromolecules from draft beer which would contain proteins from the supernatant of cultivated yeast cells. The freeze-dried powder of dialysed draft beer was dissolved in water at a concentration of 200 mg/ml. Lane a shows the mixture of beer proteins and hemoglobin. Lane b shows the fraction eluted by 0.2 M sodium acetate buffer. Lane c shows the fraction eluted by 0.01 M pyrophosphate. Lane d shows purified hemoglobin eluted by 0.04 M pyrophosphate as compared to reference hemoglobin in lane e.
FIG. 3 shows the electrophoresis results of the method of Ex. 1 on red blood cell lysate. Lane a shows the red blood cell lysate. Lane b shows the fraction on elution with 0.01 M pyrophosphate; lane c elution with 0.02 M pyrophosphate; and lane d shows purified hemoglobin on elution with 0.04 M pyrophosphate.
FIG. 4 shows the electrophoresis results of the method of Ex. 1 starting with 0.1 ml 6% hemoglobin and 0.2 ml snake venom solution prepared by dissolving dried Agkistrodon halys venom in water at 100 mg/ml. Lane a is reference hemoglobin. Lane b shows the sample mixture. Lane c is the fraction eluted by 0.2 M sodium acetate buffer. Lane d is the fraction eluted by 0.01 M pyrophosphate, and lane e shows purified hemoglobin eluted by 0.04 M pyrophosphate.
EXAMPLE 2
Sulfopropyl-Sephadex-Pyrophosphate
Although phosphocellulose works well in Example 1, other cation-exchanging matrices also provide useful purification by means of biospecific elution, including sulfopropyl-Sephadex (SP-Sephadex).
0.1 ml of 6% hemoglobin is mixed with 0.2 ml of calf serum (from Gibco Laboratories) and 0.3 ml of 0.2 M sodium acetate buffer, pH 6.0. The mixture is placed on a 1 cm x 6 cm column of sulfopropyl-Sephadex (SP-Sephadex), equilibrated with the same 0.2 M sodium acetate pH 6.0 buffer. The column is then successively developed with three bed volumes of each of:
(a) 0.2 M sodium acetate buffer, pH 6.0
(b) 0.01 M sodium pyrophosphate/0.02 M sodium acetate, pH 6.0.
FIG. 5 shows the electrophoresis of this example, wherein lane a shows the starting mixture of calf serum and hemoglobin. Lanes f and g show the fractions eluted by 0.2 M sodium acetate buffer, and lanes h and i show purified hemoglobin eluted by 0.01 M pyrophosphate.
EXAMPLE 3
Carboxymethyl-Sephadex-Pyrophosphate
Like Sulfopropyl-Sephadex, carboxymethyl-Sephadex (CM-Sephadex) is also a useful cation exchanger.
0.1 ml 6% hemoglobin solution is mixed with 0.2 ml calf serum and 0.3 ml of 0.2 M sodium acetate buffer, pH 6.0, and placed on a 1 cm x 6 cm column of C-50 grade CM-Sephadex. The column is then developed with three bed volumes each of, successively:
(a) 0.2 M sodium acetate buffer, pH 6.0
(b) 0.01 M sodium pyrophosphate/0.02 M sodium acetate, pH 6.0
(c) 0.04 M sodium pyrophosphate/0.02 M sodium acetate, pH 6.0.
FIG. 5 also shows the electrophoresis of this example, wherein lanes b and c show the fractions eluted by 0.01 M pyrophosphate, and lanes d and e show purified hemoglobin eluted by 0.04 M pyrophosphate.
EXAMPLE 4
Phosphocellulose-Pyrophosphate Batch Process
In Example 1, the biospecific elution is performed on a column of the cation exchanger phosphocellulose. In this example, it is demonstrated that biospecific elution may be performed in a batch process instead of a column process.
A suspension of phosphocellulose P11 was prepared by dispersing 4.5 ml of packed gel in 5.5 ml of 0.2 M sodium acetate buffer, pH 6.0. 0.1 ml of 6% hemoglobin and 0.2 ml of calf serum were added to the suspension, which was stirred at room temperature for 30 minutes. Afterwards, the gel was placed on suction filtration to remove excess fluid. It was washed (a) first with 0.2 M sodium acetate, pH 6.0, then (b) 0.01 M pyrophosphate in 0.02 M sodium acetate, pH 6.0, and (c) 0.04 M pyrophosphate in 0.02 M sodium acetate, pH 6.0. The washing steps (a) and (b) and the elution step (c) were each performed with 3×15 ml of solution.
FIG. 6 shows the electrophoresis of this example, wherein lane a shows the starting mixture. Lanes b and c show the fractions eluted with 0.01 M pyrophosphate, and lanes d, e and f show purified hemoglobin upon elution with 0.04 M pyrophosphate. Lane g is reference hemoglobin.
EXAMPLE 5
Phosphocellulose-Phytate
In the preceding Examples, pyrophosphate is employed as the affinity ligand to bring about a specific elution of hemoglobin from a cation exchange matrix. This example shows the feasibility of using other affinity ligands as well: in this instance inositol-hexakisphosphate, or phytate.
0.1 ml of 6% hemoglobin is mixed with 0.2 ml calf serum and 0.3 ml of 0.2 M sodium acetate buffer pH 5.0, and placed on a 1 cm×6 cm column of phosphocellulose (Sigma Co.). The column is treated successively with three bed volumes each of:
(a) 0.2 M sodium acetate buffer, pH 5.0
(b) 0.005 M sodium phytate in 0.02 M sodium acetate buffer, pH 5.0
(c) 0.01 M sodium phytate in 0.02 M sodium acetate buffer, pH 5.0.
FIG. 7 shows the electrophoresis of this example, wherein lane a is reference hemoglobin, and lane b is the sample mixture. Step (a) is shown in lanes c and d, and step (b) in lanes e, f and g. It can be seen that some hemoglobin is eluted with 0.005 M phytate. Lanes h and i show purified hemoglobin resulting from step (c).
It should be noted that this particular grade of phosphocellulose required the use of pH 5 buffer. It will be understood by those skilled in the art that suitable adjustments to process conditions may be called for to different manufacturers or from different batches from a common manufacturer.
EXAMPLE 6
Phosphocellulose--Pyrophosphate Dithionite Reduction
When heme is inserted into alpha and beta globin chains, it is in the form of ferric heme or hemin, on account of the instability of ferrous heme when it is detached from globins. Consequently, in assembling mature hemoglobin from alpha and beta globins, at some stage the heme inserted into the globins must undergo reduction. In this example, the affinity elution method of hemoglobin purification is shown to be feasible starting with methemoglobin (containing hemin) derived from globin chains and hemin, rather than hemoglobin (containing ferrous heme) as in the preceding Examples. Moreover, the reduction of hemin to heme by means of a reducing agent such as dithionite can be performed conveniently within the purification sequence, thereby permitting a combination of the purification and reduction steps, which simplify the operation and reduce costs.
2 ml of a 2% globin solution (prepared from hemoglobin, containing both alpha and beta chains) in 0.01 M phosphate buffer, pH 7.4 was stirred at room temperature. A hemin solution is prepared by dissolving 3 mg hemin (Sigma Chemical Co.) in a minimal volume of 0.1 N NaOH and diluted with distilled water to 2.5 ml. 0.2 ml of this hemin solution was added to the stirred globin solution. After 10 minutes, the mixture was filtered through filter paper to remove insoluble material.
0.3 ml of the reconstituted methemoglobin obtained in the filtrate, 0.3 ml human serum, and 0.6 ml 0.2 M sodium acetate buffer, pH 6.0, were added to a phosphocellulose P11 column (1 cm×5 cm), equilibrated with the same buffer. Eight ml of 0.01 M sodium dithionite in 0.02 M sodium acetate buffer, pH 6.0, was passed through the column in order to reduce the methemoglobin adsorbed to the phosphocellulose. Afterwards, the column was treated with, successively, three bed volumes of each of:
(a) 0.2 M sodium acetate buffer, pH 6.0
(b) 0.01 M pyrophosphate in 0.02 M sodium acetate buffer, pH 6.0
(c) 0.04 M pyrophosphate in 0.02 M sodium acetate buffer, pH 6.0.
FIG. 8 shows the electrophoresis of this example, wherein lane a is the sample mixture. Lane b shows the fraction eluted by 0.01 M pyrophosphate, and lane c shows elution by 0.04 M pyrophosphate, both lanes exhibiting purification of hemoglobin. In this Example, excess globins were employed relative to the amounts of hemin added, showing that exact stochiometric ratios between globins and hemin were unnecessary for the method to be effective. Exact stochiometric ratios are expected to be difficult to obtain when the method is to be applied to globins prepared by gene cloning methodology.
The following examples show the method of the invention used in association with an anion exchange matrix.
EXAMPLE 7
DEAE--Sephadex-Phytate
0.1 ml of 6% hemoglobin is mixed with 0.2 ml human serum and 0.3 ml of 0.2 M Tris-HCl buffer pH 9.4, and placed on a column (1 cm diameter×5 cm height) of DEAE Sephadex A-50 anion exchanger which has been equilibrated with the same 0.2 M Tris-HCl pH 9.4 buffer. The column is treated successively with four bed volumes each of:
(a) 0.2 M Tris-HCl, pH 9.4
(b) 0.003 M phytate and 0.02 M Tris-HCl, pH 9.4
(c) 0.05 M phytate and 0.02 M Tris-HCl, pH 9.4
(d) 0.10 M sodium acetate buffer, pH 6.0, containing 0.5 M NaCl.
FIG. 9 shows the electrophoresis of this example, wherein lane a is the sample mixture. Lane b shows hemoglobin eluted by 0.003 M phytate and 0.02 M Tris-HCl, and lane c shows hemoglobin eluted by 0.05 M phytate/0.02 M Tris-HCl. Lane d shows other proteins eluted by 0.1 M sodium acetate/0.5 M NaCl, and lane e shows reference hemoglobin.
EXAMPLE 8
DEAE--Sephadex-Pyrophosphate
0.1 ml of 6% hemoglobin is mixed with 0.2 ml of snake venom (100 mg/ml Agkistrodon halys venom) and 0.3 ml 0.2 M Tris-HCl buffer, pH 9.4, and loaded on a DEAE Sephadex A-50 column (1 cm×5 cm). The column is treated successively with:
(a) 0.2 M Tris-HCl buffer, pH 9.4 (3 volumes)
(b) 0.005 M pyrophosphate and 0.02 M Tris-HCl, pH 9.4 (4 volumes)
(c) 0.1 M sodium acetate buffer, pH 6.0, containing 0.5 M NaCl (3 volumes).
FIG. 10 shows the electrophoresis of this example, wherein lane a is reference hemoglobin, and lane b is the sample mixture. Lane c shows the proteins eluted by 0.2 M Tris-HCl. Lane d shows hemoglobin eluted by 0.005 M pyrophosphate/0.02 M Tris-HCl, and lane e shows proteins eluted by 0.1 M sodium acetate/0.5 M NaCl. | A method for purifying hemoglobin, mixed with other proteins is described, wherein the mixture is contacted with an ion exchange matrix so that the hemoglobin is adsorbed to it. The matrix is washed to remove unadsorbed components, and the hemoglobin is then selectively eluted using a ligand which specifically binds the hemoglobin causing it to desorb from the matrix. The method can also be used to effect reduction of methemoglobin to hemoglobin on an ion exchange matrix followed by selective elution to achieve purification. The method can also be used to purify methemoglobin. | 2 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a laser device that will enable the precise vertical positioning of a plethora of medical sensors, drainage systems, intubation systems, intravenous devices, catheters and the like with respect to a specific point on the patient's anatomy. This specific point may be the heart, the brain, a PIC line insertion point, or a drainage line insertion point.
[0002] Precise measurement of a patients vital statistics is critical with very small changes in pressure due to elevation, often having dramatic effects of drainage or supply rates, monitored pressures, static pressure scales, etc. The accurate positioning of the related sensors, scales, fluid lines and the such with respect to elevation the patient's body has heretofore been done with laser beams coupled to crude leveling devices. The battery life of these devices is generally short as the laser light's power output far exceeds what is actually needed for short range leveling. Further these early devices are susceptible to loss of accuracy by the initial calibration process, the eye of the user, the illumination of the room and from sharp impacts. Additionally, the connection of these devices to the vast array of different medical suppliers equipment and supports is problematic. Lastly, many of the prior art leveling systems are not designed to be used on either side of the patient and cannot be recalibrated.
[0003] None of the existing prior art systems allow for angular use such as would be helpful for the specific angular alignment of patient's anatomy while they go through an X-ray machine, and MRI scanner or a CAT scanner.
[0004] Henceforth, a medical laser device that could overcome the described downfalls of the prior art would fulfill a long felt need in the medical industry. This new invention utilizes and combines known and new technologies in a unique and novel configuration to overcome the aforementioned problems and accomplish this.
SUMMARY OF THE INVENTION
[0005] The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a laser device for the accurate and precise alignment of medical devices to a specific point on the patient's body.
[0006] It has many of the advantages mentioned heretofore and many novel features that result in a new medical laser alignment system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art, either alone or in any combination thereof.
[0007] In accordance with the invention, an object of the present invention is to provide an improved medical laser alignment system capable of detachment and reuse on disposable medical drain/drip systems.
[0008] It is another object of this invention to provide an improved medical laser alignment system capable of bidirectional horizontal indication by rotation of the laser about a pivot point.
[0009] It is an object of this invention to provide a medical laser alignment system that uses a multiple zero reference for the setting of the triaxial accelerometer's reference accuracy.
[0010] It is a further object of this invention to provide a medical laser alignment system that orientates its horizontal axis of illumination to the zero reference point of a triaxial accelerometer.
[0011] It is still a further object of this invention to provide for a rotatable medical laser alignment system that allows leveling for a horizontal laser light beam projection by a set of easy to see indicator lights rather than by a crude bubble level.
[0012] It is yet a further object of this invention to provide a compact, reliable medical laser alignment system that has programable accuracy, power saving features, a low battery alarm and which can be programmed such that the zero reference point of its triaxial accelerometer may be set to calibrate the laser light beam for a plethora of angles with respect to the horizontal.
[0013] The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. Other objects, features and aspects of the present invention are discussed in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a front perspective view of the medical laser device;
[0015] FIG. 2 is a front perspective view of the medical laser device with a first bracket rotated;
[0016] FIG. 3 is a front view of the medical laser device;
[0017] FIG. 4 is an end view of the medical laser device with the first bracket installed;
[0018] FIG. 5 is a side view of the medical laser device with the first bracket installed;
[0019] FIG. 6 is a front perspective assembly view of the medical laser device showing the location of all the key elements;
[0020] FIG. 7 is a rear perspective assembly view of the medical laser device showing the location of all the key elements;
[0021] FIG. 8 is a perspective view of the generic rotatable quick change attachment mechanism as formed on the front of the second alternate embodiment bracket;
[0022] FIG. 9 is a perspective view of the back of the second alternate embodiment bracket; and
[0023] FIG. 10 is a cross sectional view of the mounting orifice in the case bottom.
DETAILED DESCRIPTION
[0024] There has thus 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 hereinafter and which will form the subject matter of the claims appended hereto.
[0025] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention 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 out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting.
[0026] When discussing three dimensional coordinates herein, Cartesian coordinates are used. Thus for any particular point, there is an x, y, and z coordinate, which typically correspond to how far the object is left and right, forward and back, and up and down respectively.
[0027] The medical laser device described herein enables the precise positioning of a plethora of medical sensors, drainage systems, intubation systems, intravenous devices, catheters and the like with respect to a specific point on the patient's anatomy. For example, in many medical procedures a catheter connected to either a drainage bag or a drip bag is inserted into an opening in the human body for pressure monitoring, or the addition or removal of fluids. This is commonly done in the patient's intracranial, intravascular, intracardiac, intrapulmonary or intrafascial compartments. The pressure at the point of the opening is often critical, as the differential pressure between this and the fluid level in the bag is the motive force for the movement of the fluids. For this fluid movement to be accomplished at a controlled rate, the differential pressure between the insertion point and the bag's fluid level must be accurately known. This requires that a precise vertical alignment of the “zero point” on the static pressure scale of the bag be made. This is accomplished through the vertical alignment of a horizontal laser beam with the insertion point of the catheter. In another medical procedure it is typical to have the patient's head angled at approximately 30° with respect to the horizontal axis when the patient passes through a horizontal CAT scanner. This is accomplished by alignment of the patient's head with an angular laser beam calibrated to 30° and positioned on the bedway of the CAT scanner.
[0028] Looking at FIGS. 1 and 2 the front face and operational side of the case top 3 of the microprocessor controlled medical laser device 2 can best be seen. The case is a two part assembly made of a case top 3 and a case bottom 5 . The “ON” tab 4 is simply a U shaped cutout on the front face of the case top 3 of the laser device 2 that is able to elastically deform and flex inwards to contact the “ON” switch on the internal printed circuit board (PCB) that activates the laser diode. There is no “OFF” control of this switch as this is accomplished by a timed operation (generally set for the 30 to 40 second range) of the microprocessor. The laser diode 8 resides on the side of the PCB in alignment with the laser orifice 6 so as to allow the laser light beam 10 to project from the side of the case 3 . The top ends of three light tubes 12 extend into three orifices cut into the case top 3 . The bottom ends of these light tubes reside adjacent to three multicolor LEDs on the PCB. A first mounting bracket 14 is pivotally affixed to the case back 5 .
[0029] In operation, the user need only affix the proper mounting bracket to the case back 5 , attach the mounting bracket onto the piece of associated equipment or support pole, depress the “ON” tab 4 , point the laser light beam 10 to the desired spot on the patient while tilting the device 2 in the z axis until all three of the LEDS have sequentially changed from red to solid green, and then affixing the laser device 2 and associated equipment at this elevation.
[0030] Looking at FIGS. 3 , 4 and 5 it can be seen that the laser device 2 is generally rectangular with a thin profile where the laser light beam 10 projects centrally from one side. The bracket 14 is shorter than the device 2 and attaches centrally to the laser device 2 .
[0031] The body of the laser device 2 generally resides such that during normal operation, its longitudinal axis lies in the YZ or XZ (vertical) planes (its longitudinal axis is parallel to the Z axis) so that its laser light beam 10 projects normally (parallel to the XY plane) therefrom in the XY (horizontal) plane. It is free to rotate about the X or Y axis in this configuration.
[0032] FIGS. 6 and 7 show disassembled laser devices 2 . The components are organized left to right in their order of disassembly from the case top 3 to the case bottom 5 ( FIG. 6 ) and in their order of disassembly from the case bottom 5 to the case top 3 ( FIG. 7 ). The PCB 16 houses all of the functional components and is held in a spaced configuration within the case top 3 and case bottom 5 by a set of screws threadingly affixed in the aligned corner sockets 18 of the case's halves, passing through positioning orifices 19 in the corners of the PCB 16 . When assembled, the PCB aligns within the case such that the laser diode 8 resides adjacent the laser orifice 6 , the “ON” switch resided directly beneath the “ON” tab 4 and the light tubes 30 have their bottom ends directly over the top surface of the LEDS 22 and their top ends 12 extending through three orifices cut into the case top 3 . These three externally polished light tubes direct the LEDS' light to the surface of the laser device 2 through a torturous bending path. These light tubes 30 are rigidly affixed to the inside surface of the case top 3 .
[0033] The PCB 16 houses in electrical connectivity the following: an “ON” switch 20 ; (30 sec delay automatic off) a trio of dual color (red/green) led level indicating lights 22 (red green); a triaxial accelerometer 26 ; a microprocessor 24 ; a laser diode 8 ; a power supply 28 (3 volt Cr 2450 Lithium coin battery) accessible through door 38 ; and a connection socket 32 .
[0034] A triaxial accelerometer was selected for its three orthogonal internal sensing elements to enable simultaneous multi-axis measurements in the x, y, and z-axes.
[0035] The microprocessor 24 has a flash memory, a real time clock, a timer, a power output adjustment (the laser diode is rated to operate at a maximum of a 1 milliwatt but the microprocessor limits the power input to the laser diode at 0.5-0.9 milliwatt to reduce power consumption since the laser beam generally only extends a max of 10 feet) a multiple zero reference, (for laser accuracy) a voltage reference turn off, (for battery low power operation) and a low power visual alert (when battery voltage drops below a preset lower limit the accuracy of the accelerometer begins to decline so the microprocessor makes all three red LEDS blink signaling the need for a battery change.) A connector socket 32 allows for signal connectivity between the microprocessor 24 and the programing and calibration equipment as well as for the connection of a monitor for the visual display of the microprocessor outputs. Using this connector socket 32 a two digit lcd screen may be attached that will provide a visual user interface to indicate the angle of the laser light beam with respect to the horizontal XY plane. The triaxial accelerometer 26 is rigidly mounted to the PCB 16 as is the laser diode 8 such that hard knocks will not disturb the accuracy of the laser device 2 . Recalibration is not necessary after the initial set up has been accomplished.
[0036] In the assembly of the laser device's PCB 16 the laser diode 8 is generally aligned to emit the laser light beam 10 perpendicular to the longitudinal axis of the PCB 16 (which has its longitudinal axis in line with the longitudinal axis of the device's case. (This is done by physical alignment with precise mechanical jigs.) To accomplish this the PCB 16 is put into a jig that holds its longitudinal axis parallel to the Z axis. The jig has a set of spring loaded programing connections (terminals) that matingly contact the programming terminals of the connector socket 32 for the microprocessor 24 on the PCB 16 . The laser diode 8 is energized so as to shoot the laser light beam 10 approximately horizontal (in the XY plane) and project it onto a first reference point some distance away. (approximately 1 meter) If the laser light beam 10 does not shine on this reference point then the laser diode is mechanically adjusted (by altering the hard soldered power connectors that affix the laser diode 8 to the PCB 16 ) until it does. Then the programming unit applies the correct algorithms to determine a first zero point reading. The laser device 2 is then rotated 180 degrees such that its longitudinal axis still resides parallel to the Z axis. This procedure is repeated with respect to a second reference point at the same vertical elevation. The programing unit applies algorithms that uses these first and second readings to establish a true zero point reading for the triaxial accelerometer's reference grid and inputs this value to the microprocessor. (Thus when the triaxial accelerometer 26 sends a signal to the microprocessor 24 that the laser device 2 is positioned at this zero point, the laser light beam 10 is projecting horizontally or it is “level”.) Since the triaxial accelerometer 26 and the laser diode 8 are both mechanically fixed on the PCB 16 this calibration is good for the life of the laser device 2 . The microprocessor 24 selectively changes the color of the LEDS 22 from red to green as the signal from the triaxial accelerometer 26 indicates that it is approaching the zero point. The LEDS 22 are arranged in a row of three. The LED 22 nearest the laser diode 8 goes from red to green when the longitudinal axis of the laser device 2 is within ½th of a degree plus or minus of the zero point. The middle LED goes from red to green when the longitudinal axis of the laser device 2 is within ¼ of a degree plus or minus of the zero point. The light furthest the laser diode 8 goes from red to green when the longitudinal axis of the laser device 2 is within ⅛th of a degree plus or minus of the zero point. Accordingly, when all three LEDS 22 have changed from red to green and remain solid green the laser light beam 10 will also be projecting at ⅛th of a degree plus or minus of the horizontal axis. In an alternate, lower costing embodiment, one of the end three lights will always be green if the beam is not level, and the remaining two lights will both turn from red to green when the device 2 is less than ½ of a degree horizontal. It should be noted that other timing/indication configurations are well know in the art and could be utilized without departing from the scope of this invention.
[0037] Simply stated, the triaxial accelerometer generates and sends an electronic signal to the microprocessor 24 that represents the axial position of the laser device 2 relative to the horizontal X or Y axis. Then the microprocessor 24 applies an algorithm based on this position and generates and sends an electronic instruction that determines what color each LED 22 emits.
[0038] It is to be noted that the laser device 2 in a similar fashion to that explained above, may be calibrated so as to adjust the zero reference scale of the triaxial accelerometer 26 to any desired horizontal angle so that the laser unit may be used to align any device to a set angle without the use of a visual display connected to the device 2 through the connection socket 32 as discussed above. This is a handy feature that finds a plethora of applications outside of the medical industry.
[0039] Looking at FIGS. 6 , 8 , 9 and 10 the design and configuration of the attachment mechanism can best be seen on two different mounting brackets and its operation explained. The attachment mechanism may be fabricated onto any style of removable bracket to accommodate different medical device's mounting plates. For example, the round bracket 60 has a reinforced central section 75 that accommodates a threaded insert 76 that allows the bolted attachment of any bracket or device. The first mounting bracket 14 has a specific configuration for sliding engagement with a certain manufacturer's device. The attachment mechanism allows each bracket to be self tightening and additionally, interchangability of brackets is of a quick change, self adjusting style. Looking at FIG. 8 , the attachment mechanism has a total of 8 projections arranged in a circular fashion that extend normally from the face of the round bracket 60 . There are 4 preloaded tabs 62 and 4 snap hooks 64 that are equally interspersed. Where there is a need to hold the laser device 2 in very tight locations there is a recess on the back side of the bracket that holds a double sided adhesive patch.
[0040] Looking at FIG. 10 it can be seen that the circular mounting orifice 66 has an outer beveled peripherial ring 70 residing centrally about the orifice 66 . When the bracket 60 is being pressed into the orifice 66 , the beveled ring 70 acts to guide the snap hooks 64 such that they flex slightly inward (elastically deform) as they pass through the orifice 66 and then flex back to their original position such that the angled lock tooth 72 on each of the four snap hooks 70 engages behind the orifice 68 once the lock tooth 72 passes beyond the trailing edge 68 , thereby constraining the bracket 60 to the laser device's bottom case 5 . The four preload tabs 62 bear against the central raised flange 70 to provide frictional resistance for the rotation of the bracket 60 in the orifice 66 and to stabilize the bracket 60 with respect to the bottom case 5 . Each of the preload tabs 62 have stiffening or strengthening supports 74 to allow for repeated flexing without breaking or loss of tensioning ability. Only one of the snap hooks 64 has such a strengthening support 74 . ( FIG. 8 ) Testing has shown that one of the tabs historically has failed and requires the tab. Engagement of any bracket bearing the attachment mechanism to the bottom case 5 is accomplished by simply pressing, centrally, the two parts together. Removal is accomplished by pulling the bracket off from a single, off centered point on the bracket. Once engaged the bracket can be freely rotated with respect to the laser device 2 yet there is enough friction exerted between the 8 projections of the attachment mechanism and the orifice 66 to hold the device 2 in any orientation.
[0041] The obvious advantages of the microprocessor controlled medical laser device is that it is fast and easy to use with a high level of accuracy and reliability that is shock resistant and can be used by people with poor vision. It is capable of calibration for any desired angle, quick attachment to a plethora of mounting brackets, and has an extended battery life that lasts up to 6 times longer because of the lowered LED power output as managed by the microprocessor.
[0042] The above description will enable any person skilled in the art to make and use this invention. It also sets forth the best modes for carrying out this invention. There are numerous variations and modifications thereof that will also remain readily apparent to others skilled in the art, now that the general principles of the present invention have been disclosed. As such, those skilled in the art will appreciate that 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 insofar as they do not depart from the spirit and scope of the present invention. | A microprocessor controlled medical laser device that has a precise laser beam alignment system indicated by a series of sequentially color changing LEDS. The power management system adjusts the LED'S power input so as maximize battery life, increasing it by up to six times. It's alignment is enabled by a triaxial accelerometer that may be accurately calibrated horizontally or to a plethora of angles relative to the horizontal axis. It is shock resistant and times out to turn the laser off after a predetermined time. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus for cleaning the inner surfaces of the front and rear windows of automobiles.
2. Description of the Prior Art
Numerous scrapers and wipers for cleaning the exterior surfaces of automobile windows are known. They consist of a handle and a cleaning part fixedly connected thereto, for example a scraper, wiper blade or foam rubber strip, or combinations thereof.
In most cases, such cleaning devices must be capable of removing dirt, caked on the exterior surface of the window, by exerting a mechanical force and subsequently drying the cleaned, wet window. It is accordingly necessary to be able to exert a directed force effect on the cleaning part through the handle in order to be able to achieve a directed scraping action. Based on these considerations, the connection between the handle and the cleaning part is provided as a rigid one.
None of these considerations are valid in regard to cleaning the insides of the automobile windows. Here, no great pointed or linear pressure is required, only a flat, steady, but reduced pressure. Accordingly, the cleaning part should not be rigid per se, but flexible, and the connection between the handle and the cleaning part should be as movable as possible. Only in this way is it possible to clean the concavely-shaped and extremely hard to reach inside surfaces of automobile windows.
SUMMARY OF THE INVENTION
Based on the above considerations and experiences, a device for cleaning the inside surfaces of the windshield and rear window of an automobile having a cleaning part disposed on a handle, the cleaning part in the form of a plate which is connected with means for the removable connection of an exchangeable knuckle joint to the handle has been developed which eliminates the disadvantages of known devices and is particularly suited for cleaning the inside surfaces of automobile windows.
In accordance with one embodiment of this invention, the plate is curved such that its contact surface has a concave, cylindrical bend, the axis of curvature of which extends perpendicular to the longitudinal axis of the plate.
In this way the free adaptability of the inclination of the cleaning part relative to the handle is assured on the one hand while the rotational position of the cleaning part relative to the longitudinal axis of the handle is retained.
To achieve an even and flat cleaning of the inside surface of the automobile window, in accordance with one embodiment of this invention, means for the removable fastening of the cleaning part in the form of claw-like hooks are distributed over the surface thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages of the subject invention will be apparent from the following description in conjunction with the drawings wherein:
FIG. 1 is a perspective view of the device for cleaning the inside surfaces of the windshield and rear window of an automobile in accordance with one embodiment of this invention;
FIG. 2 shows a detail drawing of the hinged connection between the cleaning plate and the handle in accordance with one embodiment of this invention; and
FIG. 3 is a perspective view of a cleaning plate for fastening a cleaning cloth in accordance with one embodiment of this invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
The device for cleaning the inside surfaces of the windshield and rear window of automobiles in accordance with one embodiment of this invention comprises two parts, namely a handle 1 and a cleaning part 2, which are movably connected to each other by a knuckle joint 5. The cleaning part comprises a plate 3, means 4 for the removable fastening of a cleaning cloth, and the cleaning cloth 6 itself. It is essential for cleaning the windshield, in particular, that the driver can clean it quickly and cleanly using the device of this invention. The exchangeability of the cleaning cloths 6 assures cleanliness. It is essential for quick cleaning that the cleaning part 2 is connected in a limitedly movable manner to the handle 1. This limited mobility is attained with knuckle joint 5. The limited mobility results in the plate 3 being able to adapt to any inclination of the windshield, but not being able to turn arbitrarily around the longitudinal axis of the handle 1. Only in this way is it assured that the entire length of the plate 3 can be utilized during cleaning. In accordance with one embodiment of this invention, the plate 3 has a length of approximately 20 cm and as width of approximately 7 cm. It is made from polypropylene in accordance with a known injection molding process. The knuckle joint 5 is preferably molded directly to the plate 3 as shown in FIG. 1. However, in accordance with another embodiment of this invention, the plate 3 and the handle 1 are manufactured separately and fitted together with the knuckle joint 5, as shown in FIGS. 2 and 3.
The means 4 for the removable connection of a cleaning cloth 6 can be designed in many ways. In accordance with one embodiment as shown in FIG. 1, contact surface 8 of the plate 3 is provided with hooks 7, as they are known from the hook portion of a Velcro closure, over almost the entire surface. These hooks 7 can be made of one piece with the plate 3 by producing the respective injection mold by spark erosion. However, it is also possible to glue an appropriate Velcro part on the entirety of the rigid contact surface 8 of the plate 3. In this case, cleaning cloths 6, which correspond exactly in their size to the size of the plate 3 are preferably used.
In accordance with another embodiment of this invention, strips 11 of a Velcro part are glued only along the long edges of the back 9 of the plate 3. In accordance with this embodiment, cleaning cloth 6 must be wider than the width of the plate 3, so that it can be appropriately turned over, to be held by the strips 11 on the back 9 of the plate 3. So that the cleaning cloth does actually adhere to the hooks 7, it must of course have a corresponding structure. Preferably a cleaning cloth made of a non-woven material is used. Such cleaning cloths are available in various types, in particular those of relatively fluffy materials which are correspondingly absorbent and are offered commercially as wiping cloths. Alternately suitable are cloths of relatively thin fleece which are already saturated with a cleaning agent. If such moist cloths are used, they can be stored in the handle 1, which is designed as a receptacle 17 and can be closed off with a screw cap 18.
In accordance with one embodiment of this invention, plate 3 is provided over the entire contact surface with hooks 7 which themselves act in an elastically resilient manner, so that an appropriate adaptation to the windshield occurs by means of the hooks 7. In accordance with another embodiment where hooks 7 are fastened on the back 8 by strips 11, this elastic adaptation is lacking. Consequently, contact surface 8 is provided with the required elasticity by a cushioning material. Accordingly, the plate 3 is covered over its entire surface with a foam rubber layer 16, preferably a non-absorbent foam rubber. Accordingly, in accordance with one embodiment of this invention, foam rubber 16 is a closed-pore layer of polyurethane foam.
In accordance with another embodiment of this invention, means 4 for removable fastening of the cleaning cloth 6 are designed in a completely different manner as shown in FIG. 3. Here, the plate 3 is provided with foam rubber layer 16 on the contact side. But fastening of the cleaning cloth 6 is accomplished by clamping plates 13. The clamping plates 13 are preferably integral with the plate 3, and have narrow sides pivotably connected to the plate 3 by film hinges 12. Cams 14 are extruded on the back 9 of the plate 3, which fit into corresponding bores 15 in the clamping plates 13. In this way, the cleaning cloth 6 can be draped over the long edges of the plate 3 and covers the cam 14. Thereafter, the clamping plates 13 are pivoted and the cleaning cloth 6 is clamped between the clamping plate 13 and the plate 3 and is additionally held in an interlocking manner by the cam 14 and the bores 15. It is of course possible to sharpen the cams 14 to a point, so that the cleaning cloth 6 is correspondingly pierced by the cam 14. To be able to remove the dirty cleaning cloth 6 after use, it is preferred that the clamping plate 13 has an appropriate, bent-up end 19, which is used as a grip plate.
The adaptability of the plate 3 to the corresponding shape of the windshield is a particularly essential point for flawless cleaning of the curved windshield of an automobile. Contrary to expectations, this is achieved not by adapting the plate 3 as exactly as possible to the shape of the windshield, but rather by designing it contrary to the curvature of the windshield. Thus, contact surface 8 of the plate 3 is curved in such a way that it has a concave, cylindrical bend where the axis of curvature extends at least approximately perpendicularly to the longitudinal axis of the plate. This results in great elasticity of the plate 3 and the use can determine immediately whether sufficient pressure is being exerted on the plate 3. The adaptability and the complete contact of the cleaning cloth 6 with the windshield to be cleaned is therefore not mainly dependent on the thickness of the foam rubber layer 16, but on the flexibility of the plate 3, which is obtained by this appropriate shape. This curvature has been shown greatly exaggerated in the drawing figure for reasons of clarity. This curvature preferably is designed in such a way that the central curvature of the plate is approximately 3 to 6 mm. | A device for cleaning the inner surfaces of the front and rear windows of automobiles, said device having a cleaning part connected to a handle, the angle of inclination of the cleaning part relative to the handle being freely adjustable by way of an exchangeable knuckle joint without altering the angle of rotation of the cleaning part relative to the longitudinal axis of the handle. The cleaning part is arched, ensuring uniform, flat cleaning of the inner surfaces of the automobile windows. | 1 |
FIELD OF THE INVENTION
This invention relates to a fill level indicator for use in a liquefied-petroleum-gas tank. The device is particularly suitable for indicating the fill level of an automobile fuel tank.
DESCRIPTION OF THE RELATED ART
In the case of a liquefied-petroleum-gas tank it is important to precisely monitor fill-level changes. In fact, because of fuel expansion, safety considerations dictate that the tank not be filled more than 80% of its total capacity. At the low level a tank must also provide information that allows for instance a switchover to gasoline for fueling the engine.
The gauges that have been employed to date are based on a mechanical float system which has numerous drawbacks including in particular imprecise measurements due to mechanical slack, the risk of malfunction of the mechanical elements due to seizing or wear as they age, random measurement variations due to vehicle movements, the difficulty of compartmentalizing a liquefied gas tank for limiting the movement of the fluid as in the case of a gasoline tank, their bulk in the tank, and the lack of safety.
There exist gauges which incorporate optical detection devices whose operation is based on measuring the difference in the refractive index between liquid and gaseous substances. The U.S. Pat. No. 4,286,464 describes such a fill-level indicator in a tank and especially in an oil reservoir. The fill-level indicator described in that document incorporates an array of vertically staggered optical detectors. Each detector includes a light source such as a gallium and arsenic P-N LED, a receiver such as a flat P-N-P silicon phototransistor, as well as light-beam transmitting elements. These elements transmit the beam from the light source to the receiver when the detector is out of the liquid while the beam is refracted when the detector is immersed in the liquid. Electronic circuitry permits the transmission of the signals received by the detectors to an oil-level display gauge.
SUMMARY OF THE INVENTION
It is the objective of this invention to provide a fill-level indicator for liquefied petroleum gas tanks which indicator is compact, has no moving parts, is highly reliable and can be coupled to additional safety provisions such as a fill lock which is enabled when a certain level is reached or when the engine of the vehicle is running.
The device is designed to employ optical detectors whose detection principle is based on the difference in the refractive index between liquid and gaseous substances.
Accordingly, the indicator presented incorporates the following:
An array of optical detectors on a mount, vertically spaced apart from one another inside the tank and distributed over the height of the tank, with each detector encompassing a light source and a receiver, and
Means which power the light sources of the various detectors, process the information received from the different detectors and transmit it to a liquefied-gas fill-level display gauge.
According to the invention, the mount and the detectors on it are enclosed in a synthetic resin that is highly transparent to the light beams emitted by the light sources while the surface of the resin facing the detectors is such that a light beam emitted by the corresponding light source is reflected toward the associated receiver.
This design concept permits the use of optical detectors in a liquefied petroleum gas (LPG) tank in which the ambient conditions are particularly severe. With the resin it is possible to seal the sensor assembly into one solid, single block, providing excellent electrical insulation of these components from the LPG.
The level of the gas inside the tank is measured by processing the signals that have reached the different receivers, based on the fact that each of the receivers positioned in the gaseous phase receives a light beam emitted by the corresponding light source, whereas the other receivers, i.e. those immersed in liquid gas, do not receive such signals.
In one design implementation of this device, each light source consists of a diode which emits a light beam in the visible or infrared wavelength range and each receiver is constituted of a photoelectric cell or a photothyristor.
The resin used may for instance be an epoxy, given that it has a refractive index close to that of the LPG in the liquid phase.
When a detector is positioned in the gaseous phase, the emitted light beam is reflected toward the corresponding receiver since the index of the gas, at close to 1, is optically well below the index of the resin.
When the detector is positioned in the liquid phase, the beam emitted by the light source is essentially diffused in the liquid since the refractive indices of the liquid and of the resin are similar at about 1.3 to 1.4. A small part of the light beam may still be reflected toward the receiver, but the sensitivity of the latter is not such as to register light of this weak a magnitude.
The section of the resin layer covering the detectors is not contour-matched since it is important that the light path of the beam reflected by the inner wall surface of the resin be directed from the light source toward the detector. However, it is desirable to place the light source and the receiver of a given detector quite close together and to have the surface of the resin in front of the detector assembly, composed of light source and sensor, extend parallel to the detector and its mount.
In a design variation, the mount is located in a casing that serves as an outer enclosure for the resin and is highly transparent to the beams emitted by the light sources. This casing may consist for instance of polycarbonate. The refractive index of the material constituting the casing must be as close as possible to the index of the resin and of the LPG in the liquid phase.
The casing is preferably U-shaped. Each leg of the U is provided, for instance on its inner surface, with a longitudinal groove and the two grooves serve to accept the detector mount in such fashion that it extends parallel to the base of the casing. The detector mount is thus perfectly aligned in the casing, providing good parallelism between the base plane of the casing and the plane of the detector mount. Of course, surfaces other than these planar surfaces can be utilized for the base and the mount, but the planar configuration offers the advantage of being the easiest to implement.
For fitting the probe in the tank containing the LPG, the mount, the resin and possibly the casing are enclosed in a retaining head that is attached to the tank. This retaining head may for instance be a metal head equipped with an annular flange and bolted to the tank. This allows the heed to be mounted in the location usually occupied by a traditional float-type mechanical gauge, fastened to the tank with four screws.
To ensure proper electrical connection between the detectors of the probe and the outside of the tank, an insulated wire conduit is suitably installed in the retaining head.
According to one advantageous embodiment of the indicator per this invention, the mount supporting the detectors consists of a printed circuit board.
In a preferred design implementation the means for supplying electric power to the light sources and for processing the signals include a microprocessor or microcontroller.
Since the fill-level indicator only provides discrete i.e. discontinuous measurements, it will be desirable to prevent the needle of the gauge from dropping upon every change of the state of a detector. This is accomplished in that the signal processing means perform a smoothing function on the value of the gauge shift between the corresponding measurements of two neighboring detectors, simulating intermediate measurements between two actual measuring points by the interpolation of a mean gas consumption value during an average time period.
To avoid registering every interference-induced change in the state of the detectors which does not reflect the actual level of the liquid, caused by the splashing of droplets, a wave motion due to movements of the vehicle or a leaning of the vehicle, the signal processing elements include a change-of-state filtering provision for the detectors which establishes a time period during which no variation in the detection is to be registered. This time period can be relatively short, with a duration on the order of a few seconds, depending on the desired sensitity level.
As an advantageous feature of this invention when applied to an automobile tank, the signal processing means are connected at one end to the electric distribution panel of the vehicle engine and at the other end to a solenoid valve installed on the tank filler inlet, enabling the solenoid valve to open up only when the engine is stopped and when the fluid is below a specific level, the maximum fill level being 80% of the tank capacity which corresponds to the position of the uppermost detector.
The device per this invention thus incorporates important safety functions. It should be noted that in conventional systems the overfill prevention is implemented by mechanical means employing a float, which again has the same shortcomings as those mentioned above in connection with the gauge.
To ensure highly safe operation of the device, the signal processing means include for instance a test function for all optical detectors and for the various electronic components which may be subject to possible malfunction.
For safety reasons, if the maximum-fill detector were to fail, its functions are automatically transferred to the next lower detector, or the filler solenoid valve remains closed.
The signal processing means which include a microcontroller or a microprocessor may also be designed in a way as to reduce electric power consumption when idle, i.e. when the vehicle is stopped, or to conserve the power for retaining control of the solenoid valve in the fill position. It is possible to provide these signal processing elements with an interface to the electronic fuel injection system for the purpose of enhanced performance and safety of the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be better understood with the aid of the following description with reference to the attached drawings, illustrating non-limiting examples of several forms of implementation of this device.
FIG. 1 shows the liquefied-petroleum-gas tank of a vehicle, equipped with a device per this invention together with its connections to various functional components of the vehicle;
FIGS. 2 and 3 represent two cross-sectional views of an optical detector respectively outside and inside the liquefied petroleum gas along lines II—II and III—III in FIG. 1;
FIGS. 4 and 5 respectively represent an exploded and an assembled view of the fill-level indicator according to this invention;
FIG. 6 is an exploded perspective view of a device per this invention and a corresponding retaining head;
FIG. 7 shows a cross-section through a detector; and
FIG. 8 is an exploded perspective view, on an enlarged scale, of the free end of the device per FIG. 6 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a liquefied-petroleum-gas tank 2 designed for use in an automobile. Above the liquid gas 3 contained in the tank is a gaseous volume 4 . The tank is equipped with an essentially conventional filler unit 5 , mounted on which is a solenoid valve 6 that operates a flap 7 which depending on its position permits or blocks the filling of the tank
The fill-level indicator incorporates a bar 8 which, in the implementation shown in the drawing, extends vertically inside the tank. This bar holds an array of detectors 9 each of which includes a light source 10 consisting for instance of a visible- or infrared-range light-emitting diode, and a receiver 12 consisting of a photoelectric cell or a photothyristor. The bar 8 may be in the form for instance of a printed circuit board. The various detectors 9 are attached to the bar 8 which serves as a mount and is encased in a synthetic resin 13 whose refractive index is close to the refractive index of the liquid gas. In the implementation per FIGS. 2 and 3 the optical axes of the light source 10 and the corresponding receiver 12 are parallel. The light source 10 and the receiver are close together and the surface of the resin 13 facing the detector 9 extends parallel to the mount 8 constituted of the flat printed circuit board. Correspondingly, the light beam emanating from the source 10 is reflected and directed toward the receiver 12 . When the detector is positioned in the gaseous phase 4 , the result as shown in FIG. 2 will be a nearly total reflection of the light beam toward the receiver 12 , with the refractive index of the gas 4 being well below the index of the resin. By contrast, when, as shown in FIG. 3 and represented by the intersecting line III—III in FIG. 1, a detector is immersed in liquid gas, most of the light beam emitted by the source 10 is diffracted within the liquid gas 3 , with the refractive indices of the liquid and of the resin 13 being very similar.
The analysis of the signals emitted by the different receivers 12 of the detectors 9 permits the determination of which detectors are immersed and which are not, and thus a measurement of the fill-level of the liquid.
As shown in FIGS. 4 to 8 , one approach to implementing a fill-level indicator is to insert a bar 8 with detectors 9 in a casing 16 in the form of a U-shaped trough. The casing 16 is then filled with a synthetic material that is transparent to the light beam while perfectly insulating the detectors 9 as well as their power-supply and signal-acquisition elements from the liquid and gaseous fluids in the tank 2 . An example of such synthetic material is epoxy resin.
The casing 16 is a channel with a U-shaped cross section. It thus has two legs 23 and a base 24 . Each leg 23 is provided on its inside with a groove 25 that extends longitudinally over the entire length of the casing 16 . The two grooves 25 are so designed that the printed circuit board mount 8 can slide and be guided in them and can be positioned parallel to the base 24 of the casing. The latter may be produced for instance of polycarbonate. The printed circuit board 8 is inserted in the casing 16 in such fashion that the detectors 9 face the base of the casing and are perfectly parallel to it.
Thus assembled, the casing is inserted in flush fashion in a retaining head 26 . This retaining head, made of metal, is attached to the tank with four screws via an annular flange, not shown, in the location usually serving to accept a conventional mechanical float-based gauge. The metal head 26 absorbs the pressure exerted by the LPG in the tank 2 . A cavity 27 matching the shape of the casing is provided in the retaining head 26 in such fashion that the head is translationally locked in place as the gas pressure bears on it. A fastening hole 32 serves to secure the casing 16 on the retaining head 26 .
An insulated wire conduit 28 through which extend metal pins 29 is mounted in the retaining head 26 , serving as the terminal pin connection. The male pin connectors thus protrude from the head 26 to the outside of the tank. They connect to an electronics box 17 which will be described further below. This link to the electronics box 17 is established for instance by means of female connectors, not shown, or by wires soldered to the male pin connectors, and is then potted in epoxy resin, sealing the assembly.
After all these components are assembled, the probe is laid sideways for encapsulation in epoxy resin which is applied by simple gravitational flow. The resin is carefully selected for its transparency to the emitted light beam and its compatibility with the LPG while at the same time ensuring good mechanical qualities in terms of hardness, electrical insulation and thermal resistance after polymerization. As shown in FIG. 8, for pouring the resin the end of the casing 16 opposite the retaining head 26 is covered with a lid 30 which tightly closes off the end of the casing. A space is left between the mount 8 and the lid 30 to allow the epoxy resin to flow on both sides of the mount 8 .
The resulting trough is completely filled horizontally. When polymerized, the resin seals the assembly into a single solid block, galvanically insulating the electric currents from the LPG. In addition, the resin ensures perfect tightness of the casing and of the wire conduit in the head of the probe.
The horizontal pouring process permits substantial elimination of microbubbles within the resin, bubbles which could interfere with the optical path of the light beam emitted by a light source 10 of the detector 9 .
Since the light sources 10 are very close to the receivers 12 , the base 24 of the casing 16 must be flat. The distance between the detectors 9 and the base 24 of the casing, i.e. the thickness of the resin layer 13 covering the detectors 9 , must be kept minimal so as to minimize any deviation of the light path on the flat surface.
To reduce possible interference with the transmission of the light beam to a minimum, the casing could conceivably be removed to leave only a block of resin 13 surrounding the mount 8 and the detectors 9 . In fact, with the casing, even if the refractive indices of the resin and of the material constituting the casing are very close (about 1.5 to 1.6), the presence of a diopter between the resin and the casing causes a deviation of the light beam. Therefore, any such diopter should preferably be avoided. This leads to an implementation as shown in FIG. 7 which is a cross-sectional view of a probe without a casing. The result is a mount 8 with detectors 9 , as shown in FIGS. 2 and 3, encapsulated in a block of resin 13 .
As indicated in FIG. 1, the bar 8 connects to an electronics box 17 . This box on its part is connected to the battery 18 of the vehicle, to the distribution panel 19 permitting electric current to be fed to the engine, to the fuel fill-level display gauge 20 on the vehicle dashboard, and to the electronic engine fuel injection system 22 . The electronics box 17 , possibly comprising a microprocessor or microcontroller, feeds power from the battery 18 to the diodes 10 which constitute the light sources. This box 17 performs various signal processing functions aimed both at providing a readout of the liquid gas level in the tank and at assuring a safe installation.
Note that the probe delivers only discontinuous measurements. To avoid having the needle of the gauge 20 drop every time there is a change in state of a detector, a smoothing function is provided which permits a gradual decline of the needle by simulating intermediate measurements between two actual measuring points, with an interpolation of a mean gas consumption value over an average length of time. The smoothing function is reset for the change of state of each detector.
The box 17 also ensures a filtering of sudden changes of state of the detectors by integrating a time delay during which detection variations will not register.
The bottom-most detector, when immersed in the liquid, sends to the electronics box 17 a signal permitting it, for example, to initiate the automatic switchover to gasoline for fueling the engine.
For safety reasons and especially in order to allow for an increased pressure of the gaseous phase in higher temperature conditions, the tank must not be filled more than 80% of its total capacity. It is therefore possible to install a maximum-level detector which, when activated by a high level of liquid, sends a signal to the electronics box on the basis of which the latter can instruct the solenoid valve 6 to ensure the closure of the filler unit. The electronics box 17 is also connected to the distribution panel 19 for the purpose of preventing the filling of the tank while the engine of the vehicle is running.
The detectors 9 are mounted at space intervals carefully chosen in consideration of the shape of the tank. Accordingly, they are closer together in the bottom part of the tank to assure greater measurement accuracy as the liquid level approaches the fuel “reserve”. This irregular placement of the detectors permits employing the same signal processing electronics regardless of the type of tank. The optical probe itself (the detectors encapsulated in resin) is specifically adapted to each type of tank while the signal processing module (measurement interpretation, smoothing, actuator control, message to the dashboard gauge, etc.) remains the same for all models, thus considerably reducing manufacturing costs.
The electronics box 17 ultimately ensures automatic control of the detectors by sending a signal in the event one of the detectors is malfunctioning. If the maximum-fill-level detector fails, its functions are immediately transferred to the next lower detector. As an alternative, the microcontroller or microprocessor can interdict any refilling while that detector is failing by keeping the solenoid valve closed.
Turning off the engine triggers the opening of the solenoid valve on the filler unit for a duration τ. If during that time period τ the 80% maximum-fill-level detector or the engine starter are not used, a delay device causes the solenoid valve to close.
As will be evident from the above, this invention constitutes a major improvement on the state of the art by providing a fill-level indicator for liquefied petroleum gas tanks that is compact, has no moving parts, is not affected by normal pressure or temperature fluctuations in the range respectively from 0 to 30 bars and minus 20° C. to plus 65° C., while offering excellent accuracy and outstanding reliability.
It goes without saying that this invention is not limited to the design implementations described above by way of examples but, on the contrary, it embraces all possible variations. Specifically, the number of detectors may differ, their placement in the tank may differ, and the shape of the casing associated with the detectors may differ, without departing from the substance of this invention. | Fill-level indicating device includes an array of optical detectors attached to a mount, vertically spaced apart relative to one another and distributed within the tank over the height of the latter, with each detector including a light source and a receiver, and means for feeding electric power to the light sources of the various detectors, for processing the signals arriving at the various receivers and for transmitting these to a liquefied-gas fill-level display gauge. The mount and the detectors on it are encapsulated in a synthetic resin that is highly transparent to the light beam emitted by the light sources and the surface of the resin facing the detectors is such that the beam emitted by the corresponding light source is reflected toward the associated receiver. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based on and claims the benefit of priority from earlier Japanese Patent Application No. 2009-106554 filed Apr. 24, 2009, the description of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field of the Invention
[0003] The present invention relates to an engine starting apparatus which is able to engage a pinion of a starter with a freewheeling ring gear in the course of an engine stop process to restart the engine.
[0004] 2. Related Art
[0005] Providing vehicles with an idle stop system is an important approach to reducing CO 2 as one of the countermeasures against global warming. The idle stop system is a system, for example, that stops fuel injection to an engine to automatically stop the engine when the vehicle is stopped at an intersection due to a stop signal or in pause due to traffic jam or the like.
[0006] Conventional idle stop systems have been configured to automatically stop an engine after the vehicle has been fully stopped. In order to further improve the effect of reducing CO 2 , it is effective to elongate an engine stop period. Elongating the engine stop period may be specifically achieved by a system that stops an engine before the vehicle speed runs out (i.e. during the deceleration preceding the vehicle stop), converting from the conventional systems that stop the engine after the vehicle has been fully stopped. It is expected that such a system that elongates the engine stop period may significantly improve the effect of reducing CO 2 , compared to the conventionally used idle stop systems.
[0007] However, this system raises an issue incurred in a potential restart of an engine after the engine has entered an engine stop process. Specifically, in conventional starters, the pinion of the starter cannot be engaged with the ring gear of the engine unless the engine is fully stopped. This means that, in the case where an engine is restarted using a conventional starter, the engine cannot be restarted from the point when the engine has entered the engine stop process up to the point when the engine is completely stopped. There may be a situation, for example, that the traffic light at an intersection is red and the vehicle is decelerated accordingly followed by the output of a stop command to allow the engine to enter the engine stop process, and that, then, the traffic light quickly turns green. In such a situation, conventional starters cannot immediately restart the engine, which may cause trouble to the following vehicle and impose a psychological burden on the user. Accordingly, in order to use the idle stop function while the vehicle is decelerating, it is essential to enable restart of the engine when the engine is in the engine stop process.
[0008] In order to realize restart during the engine stop process, the pinion of the starter is required to be in engagement with a ring gear in rotation. A technique as a method of realizing such a restart is disclosed in WO2007/101770. Specifically, this patent document discloses a method of restarting an engine using a starting device that includes a first RPM detecting means that detects the number of revolutions of a ring gear, a second RPM detecting means that detects the number of revolutions of the pinion of a starter or the number of revolutions of a motor, and a motor revolution control driver that controls the number of revolutions of the motor. In this starting device, the number of revolutions of the pinion is controlled by the motor revolution control driver based on the number of revolutions detected by the first and second RPM detecting means, for synchronization with the number of revolutions of the ring gear. As a result, the pinion is engaged with the ring gear.
[0009] The method disclosed in WO2007/101770 (the method of synchronizing the number of revolutions of a pinion with that of a ring gear to establish engagement between the gears) is an ideal method in the case where gears distanced from each other are brought into engagement with each other. However, this method has a large problem of requiring a motor revolution control driver that controls the number of revolutions of a motor. Generally, an MOS transistor as a control element is used as a motor revolution control driver to perform voltage control (e.g., pulse width control, so-called PWM control). However, starter motors have a low voltage (usually 12 V) in spite of having a large output. Therefore, this necessitates the use of an MOS transistor having a large current capacity exceeding 500 A and thus greatly raises the cost as a result.
[0010] In addition, achieving synchronization between the numbers of revolutions of a pinion and a ring gear may require feedback control of the numbers of revolutions. As a result, a long time will be taken for the synchronization. Therefore, in many cases, there is a concern that synchronization is unlikely to be completed during the very short time in which the engine speed is decreasing.
SUMMARY OF THE INVENTION
[0011] The present invention has been made in light of the problems set forth above and has as its object to provide an on-vehicle engine starting apparatus which is able to engage a starter's pinion with an engine's ring gear, which is in the state of decreasing revolutions, during the short time of an engine stop process to thereby restart the engine.
[0012] In order to achieve the object, an engine starting apparatus is provided which comprises an electric motor which receives current to generate a rotational force, an output shaft that has an outer periphery surface and rotates by the rotational force, a one-way clutch that is helical-spline-fitted to the outer periphery surface of the output shaft, a pinion that receives the rotational force via the one-way clutch, a pinion pushing device that pushes, together with the one-way clutch, the pinion toward a ring gear of an engine, the one-way clutch having an idling torque smaller than a torque of the ring gear that tries to turn the pinion when the pinion is pushed to the ring gear, and a current switching device that turns on/off the current supplied to the motor. The apparatus further comprises a revolution speed detecting device that detects a revolution speed of the ring gear, and a control device. The control device enables the pinion pushing device to operate when the revolution speed of the ring gear detected by the revolution speed detecting device is larger than a revolution speed of the pinion acquired from a revolution speed of the motor and a relative revolution speed between the revolution speed of the ring gear and the revolution speed of the pinion is a desired value. This control device is able to control the operations of the pinion pushing device and current switching device independently from each other.
[0013] In the case where engine restart is requested while the number of revolutions of the ring gear is decreasing in an engine stop process, the engine starting apparatus of the present invention actuates the pinion pushing device when the ring gear and the pinion rotate at predetermined relative numbers of revolutions (the number of revolutions of the ring gear>the number of revolutions of the pinion) to thereby allow the pinion to be pushed to the ring gear side integrally with the one-way clutch.
[0014] The actuation of the pinion pushing device brings the end face of the pinion into contact with the end face of the ring gear. When the pinion is pressed against the ring gear being applied with a predetermined load, the number of revolutions of the pinion instantaneously synchronizes with that of the ring gear with the idling of the one-way clutch. This is because the rotational torque of the one-way clutch in an idling state is set smaller than the rotational torque with which the ring gear attempts to rotate the pinion.
[0015] From the instance of the synchronization as well, the revolutions of the ring gear still continue decreasing. In this case, however, the pinion will not decrease revolutions synchronized with the revolutions of the ring gear because the one-way clutch is on the connecting side (torque transmitting side). Accordingly, the ring gear will separate from the pinion in the direction opposite to the direction of revolutions, whereby engagement is established between the pinion and the ring gear.
[0016] It should be appreciated that the engine speed does not have to be directly detected, but a crank angle sensor or the like may be used.
[0017] It is preferred that, in the foregoing configuration, the output shaft provides an axial direction which is along a longitudinal direction of the output shaft, the ring gear has a first periphery surface on which a plurality of teeth are formed, the teeth of the ring gear having a first axial end face facing the pinion and being directed in the axial direction, the pinion has a second periphery surface on which a plurality of teeth are formed, the teeth of the pinion having a second axial end face facing the ring gear and being directed in the axial direction, and recesses are formed on at least one of the first axial end face and the second axial end face and formed in a direction crossing a rotational direction of the ring gear and the pinion.
[0018] With this configuration, the pinion is pushed with the actuation of the pinion pushing device. Then, when the end face of the pinion comes into contact with the end face of the ring gear, the recess formed in the pinion end face, for example, will be caught by the teeth of the ring gear. In this way, the revolutions of the pinion can instantaneously follow (synchronize with) those of the ring gear, thereby promptly establishing engagement.
[0019] It is also preferred that frictional coefficient increasing means is formed on at least one of the first axial end face and the second axial end face to increase a frictional force thereon.
[0020] With this configuration, the pinion is pushed with the actuation of the pinion pushing device. Then, when the end face of the pinion comes into contact with the end face of the ring gear, frictional force between the both end faces will be increased by the frictional coefficient increasing means. In this way, the revolutions of the pinion can instantaneously follow (synchronize with) those of the ring gear, thereby promptly establishing engagement.
[0021] Preferably, the recesses are chamfered portions formed at least one of the ring gear and the pinion, the chamfered portions being at least one of i) chamfered portions crossing both the first periphery surface and the first axial end face and ii) chamfered portions crossing both the second periphery surface and the second axial end face.
[0022] With this configuration, it is highly probable that the teeth of the pinion and the teeth of the ring gear are caught with each other after in the axial direction after the pinion has come into contact with the ring gear. Thus, reliability in the synchronization of the revolutions between the pinion and the ring gear can be enhanced. In a vehicle having an idle stop function, it is required to consider the case where the engine may be started without using the idle stop function, i.e. started in a conventional manner, for a certain number of times. In this regard, formation of the chamfered portions can ensure the engagement performances based on both of the startup using the idle stop function and the startup in the conventional manner.
[0023] Still preferably, the frictional coefficient increasing means is composed of a plurality of grooves. It is preferred that each of the grooves has a depth which is smaller than a module of the pinion and the ring gear. For example, the depth is smaller than 1/n of the module (n is a positive integer of 9 or less). The module is a size (i.e., height) of each tooth of each of the pinion and ring gear.
[0024] With this configuration, the frictional coefficient increasing means can be easily formed using a means, such as a knurling tool, which can facilitate processing.
[0025] It is also preferred that the motor is a brush type of DC motor having an armature, a rectifier arranged at the armature, a brush made in contact with a surface of the rectifier, and a spring pushing the brush to the surface of the rectifier, wherein the armature has a torque larger than the idling torque of the one-way clutch.
[0026] With the actuation of the pinion pushing device, the pinion is pressed by the ring gear and thus the revolutions of the pinion will follow and synchronize with the revolutions of the ring gear. After the synchronization as well, the ring gear still continues decreasing the number of revolutions. Thus, the torque of the ring gear works on the pinion such that the revolutions of the pinion are decreased. In this regard, since the one-way clutch structured integrally with the pinion is on the connecting side (torque transmitting side), the torque that works on the pinion such that the revolutions of the pinion are decreased will be transmitted to the motor side.
[0027] Meanwhile, in the motor of the present invention, a braking force works on the revolutions of the armature when the brush is pressed against the surface of the rectifier by the brush spring. Accordingly, the armature is unlikely to be rotated from the ring gear side. As a result, the pinion will not decrease its revolution speed synchronizing with the decreasing revolutions of the ring gear. This will permit easy deviation between the teeth of the pinion and the teeth of the ring gear. Thus, the time required for achieving engagement between the pinion and the ring gear can be shortened.
[0028] Preferably, the engine starting apparatus further comprises a reduction device which reduces a rotational speed of the motor and transmits the reduced rotational speed of the motor to the output shaft.
[0029] The torque of the ring gear, which works on the pinion such that the revolutions of the pinion are decreased, may be transmitted to the motor side. In such a case, an arrangement of the reduction gear between the motor and the output shaft may allow the armature to be more unlikely to be rotated from the ring gear side. Thus, it is ensured that the teeth of the pinion and the teeth of the ring gear are easily deviated (separated), whereby the time taken for completing engagement between the pinion and the ring gear is further shortened.
[0030] Preferably, the control device includes a delay device that allows the current switching device to start to operate when a predetermined period of time has passed since the start of a pushing operation of the pinion.
[0031] According to the present invention, the pinion can be fully engaged with the ring gear and then, in this fully engaged state, current is passed to the motor to start the engine. Thus, the pinion and the ring gear can be prevented from being damaged due to potential incomplete engagement therebetween when the revolutions of the ring gear are decreasing in the engine stop process. As a result, the life of each of the gears can be improved in a vehicle having an idle stop function, in which the starter is actuated for a number of times.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In the accompanying drawings:
[0033] FIG. 1 is a general view, with partly cut, illustrating a starter incorporated in an engine starting apparatus according to an embodiment of the present invention;
[0034] FIG. 2 is a cross-sectional view illustrating a pinion-pushing solenoid and a motor electrification switch of the starter;
[0035] FIG. 3 is an electric circuit diagram illustrating the engine starting apparatus of the starter;
[0036] FIGS. 4A to 4D are explanatory views illustrating an operation in a first situation, in which a pinion engages with a ring gear which is decreasing revolutions in an engine stop process;
[0037] FIGS. 5A to 5D are explanatory views illustrating an operation in a second situation, in which a pinion engages with a ring gear which is decreasing revolutions in an engine stop process;
[0038] FIG. 6 is a graph illustrating engine speed in an engine stop process with time being indicated on the horizontal axis;
[0039] FIG. 7 is a diagram illustrating the ring gear and the pinion as viewed from the axial direction;
[0040] FIG. 8 is a diagram illustrating an example of a frictional coefficient increasing means formed in a pinion end face; and
[0041] FIG. 9 is a schematic diagram illustrating the configuration of a motor with a brush.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] With reference to the accompanying drawings, hereinafter will be described embodiments of an engine starting apparatus according to the present invention.
[0043] Referring to FIGS. 1 to 9 , an embodiment of the engine starting apparatus will now be described.
[0044] The engine starting apparatus is used for an idle stop system that automatically controls stop and restart of an on-vehicle engine. The engine starting apparatus includes a starter 1 (shown in FIG. 1 ), an ECU (electronic control unit) 2 (shown in FIG. 3 ), and an RPM detector 4 (shown in FIG. 3 ). The starter 1 starts an engine (i.e., internal combustion engine) mounted on a vehicle. The ECU 2 controls the operation of the starter 1 . The RPM detector 4 detects a signal indicative of the number of revolutions of a ring gear 3 attached to a crank shaft of the engine and outputs the detected signal to the ECU 2 .
[0045] As shown in FIG. 1 , the starter 1 includes an electric motor 5 , an output shaft 6 , a pinion movable body (described later), a shift lever 7 , a pinion-pushing solenoid 8 , a battery 9 , and a motor electrification switch 10 . In the present embodiment, directions can be defined such that longitudinal directions of the output shaft 6 are axial directions AX, radially extending directions from the output shaft 6 along a plane perpendicular to the axial directions are radial directions RA, and directions circulating around the axial directions along the plane perpendicular to the axial directions are circumferential directions CR.
[0046] The motor 5 generates torque in response to current supply thereto. The output shaft 6 rotates being transmitted with the torque generated by the motor 5 . The pinion movable body is provided such that it is axially movable on the outer periphery of the output shaft 6 . The pinion-pushing solenoid 8 has a function of pushing the pinion movable body in the direction opposite to the motor (leftward in FIG. 1 ) via the shift lever 7 . The motor electrification switch 10 opens/closes a motor contact which is provided at a motor circuit to pass current from the battery 9 (see FIG. 3 ) to the motor 5 .
[0047] The motor 5 is an electric dc motor with a brush, including a field magnet 11 , armature 14 and a brush 16 . The field magnet 11 is configured by a plurality of permanent magnets. The armature 14 includes an armature shaft 12 with its one end being provided with a rectifier 13 . The brush 16 is arranged being in contact with an outer peripheral surface of the rectifier 13 (hereinafter referred to as a “rectifier surface”) and pressed against the rectifier surface by a brush spring 15 (see FIG. 9 ). The field magnet 11 of the motor 5 , which is made up of the permanent magnets, may be replaced by a field electromagnet made up of a field coil.
[0048] The output shaft 6 is arranged being aligned with the armature shaft 12 via a reduction gear 17 . Thus, the revolutions of the motor 5 are transmitted being reduced by the reduction gear 17 .
[0049] The reduction gear 17 is a known planetary reduction gear, for example, in which a planetary carrier 17 b that picks up the orbital motion of a planetary gear 17 a is provided being integrated with the output shaft 6 .
[0050] The pinion movable body is configured by a clutch 18 and a pinion 19 .
[0051] The clutch 18 includes a spline sleeve 18 a, an outer 18 b, an inner 18 c, a roller 18 d and a roller spring (not shown). The spline sleeve 18 a is helical-spline-fitted to the outer periphery of the output shaft 6 . The outer 18 b is provided being integrated with the spline sleeve 18 a. The inner 18 c is relatively rotatably arranged at the inner periphery of the outer 18 b. The roller 18 d is located between the outer 18 b and the inner 18 c to connect/disconnect torque therebetween. The roller spring has a role of biasing the roller 18 d. The clutch 18 is provided as a one-way clutch that unidirectionally transmits torque from the outer 18 b to the inner 18 c via the roller 18 d.
[0052] The pinion 19 is integrated with the inner 18 c of the clutch 18 and relatively rotatably supported by the outer periphery of the output shaft 6 via bearings 20 .
[0053] The pinion-pushing solenoid 8 and the motor electrification switch 10 have a solenoid coil 21 and a switch coil 22 , respectively, each of which forms an electromagnet when current is passed. A fixed core 23 is arranged between the solenoid coil 21 and the switch coil 22 so as to be commonly used by these coils. The outer periphery of the pinion-pushing solenoid 8 is covered with a solenoid yoke 24 , while the outer periphery of the motor electrification switch 10 is covered with a switch yoke 25 . The solenoid yoke 24 and the switch yoke 25 are integrally and continuously formed in the axial directions AX to provide a single overall yoke. In other words, as shown in FIG. 1 , the solenoid 8 and the switch 10 are integrally configured in series in the axial directions AX, disposed being parallel to the motor 5 , and fixed to a starter housing 26 .
[0054] FIG. 2 is a cross-sectional view illustrating the pinion-pushing solenoid 8 and the motor electrification switch 10 of the starter 1 . As shown in FIG. 2 , the overall yoke has a bottomed cylindrical shape with one axial end (first end E 1 ) (left side in FIG. 2 ) being provided with an annular bottom and the other axial end (second end E 2 ) being opened. The outer diameter of the overall yoke is made even from the first end E 1 to the second end E 2 . However, the inner diameter of the switch yoke 25 is ensured to be larger than that of the solenoid yoke 24 . Accordingly, the thickness of the switch yoke 25 is smaller than that of the solenoid yoke 24 . In other words, the inner peripheral surface of the overall yoke has a step between the solenoid yoke 24 and the switch yoke 25 .
[0055] The fixed core 23 is inserted from an open end that is the second end E 2 of the overall yoke (open end of the switch yoke 25 ) into the inside of the switch yoke 25 . The inserted fixed core 23 has a radially outer end face on the first end E 1 side. This radially outer end face is brought into contact with the step provided at the inner peripheral surface of the overall yoke, between the solenoid yoke 24 and the switch yoke 25 , to determine the axial position of the fixed core 23 .
[0056] Referring to FIGS. 2 and 3 , hereinafter is described the configurations of the pinion-pushing solenoid 8 and the motor electrification switch 10 , except for the overall yoke (the solenoid yoke 24 and the switch yoke 25 ) and the fixed core 23 .
[0057] The pinion-pushing solenoid 8 includes the solenoid coil 21 , a plunger 27 and a joint 28 . The solenoid coil 21 is arranged along the inner periphery of the solenoid yoke 24 that forms a part of the overall yoke on the first end E 1 side. The plunger 27 is disposed being opposed to one radially inner attractive surface S 1 of the fixed core 23 and is permitted to be axially movable along the inner periphery of the solenoid coil 21 . The joint 28 transmits the movement of the plunger 27 to the shift lever 7 .
[0058] FIG. 3 is an electric circuit diagram illustrating the engine starting apparatus of the starter 1 . As shown in FIG. 3 , the solenoid coil 21 has an end connected to a connector terminal 29 and the other end grounded being fixed to a surface of the fixed core 23 , for example, by welding or the like. An electrical wiring connected to a starter relay 30 is connected to the connector terminal 29 .
[0059] The starter relay 30 is subjected to on/off control of the ECU 2 . When the starter relay 30 is controlled and turned on, current is passed from the battery 9 to the solenoid coil 21 via the starter relay 30 .
[0060] When the fixed core 23 is magnetized with the supply of current to the solenoid coil 21 , the plunger 27 is attracted to the attractive surface S 1 of the fixed core 23 against the reaction force of a return spring 31 disposed between the fixed core 23 and the plunger 27 . Then, when the current supply to the solenoid coil 21 is stopped, the plunger 27 is pushed back by the reaction force of the return spring 31 in the direction opposite to the fixed core 23 (leftward in FIG. 2 ). The plunger 27 has substantially a cylindrical shape with a cylindrical hole being formed at its radially central portion. The cylindrical hole is open at one axial end of the plunger 27 and bottomed at the other end thereof.
[0061] The joint 28 having a shape of a rod is inserted into the cylindrical hole of the plunger 27 together with a drive spring (not shown). Thus, the joint 28 has an end portion projected from the cylindrical hole of the plunger 27 . This end portion of the joint 28 is formed with an engagement groove 28 a with which one end portion of the shift lever 7 engages. The other end portion of the joint 28 is provided with a flange portion. The flange portion has an outer diameter that enables the flange portion to be slidably movable along the inner periphery of the cylindrical hole. The flange portion, being loaded by the drive spring, is being pressed against the bottom face of the cylindrical hole.
[0062] With the movement of the plunger 27 , an end face 19 a (see FIG. 1 ) of the pinion 19 pushed in the direction opposite to the motor comes into contact with an end face 3 a (see FIG. 1 ) of the ring gear 3 . Then, the drive spring is permitted to bow while the plunger 27 is permitted to move and attracted to the attractive surface S 1 of the fixed core 23 . Thus, the drive spring accumulates reaction force that allows the pinion 19 to engage the ring gear 3 .
[0063] The motor electrification switch 10 includes the switch coil 22 , a movable core 32 , a contact cover 33 , two terminal bolts 34 and 35 , a pair of fixed contacts 36 , and a movable contact 37 . The switch coil 22 is arranged along the inner periphery of the switch yoke 25 forming a part of the overall yoke on the second end E 2 side. The movable core 32 faces the other radially inner attractive surface 52 of the fixed core 23 and is permitted to be movable in the axial directions AX of the switch coil 22 . The contact cover 33 , which is made of resin, is assembled, blocking the open end, i.e. the second end E 2 , of the overall yoke (the open end of the switch yoke 25 ). The two terminal bolts 34 and 35 are fixed to the contact cover 33 . The pair of fixed contacts 36 are fixed to the two terminal bolts 34 and 35 . The movable contact 37 electrically connects/disconnects between the pair of fixed contacts 36 .
[0064] As shown in FIG. 3 , the switch coil 22 has one end connected to an external terminal 38 , and the other end grounded being fixed, for example, to a surface of the fixed core 23 by welding or the like. The external terminal 38 is provided being projected out of an axial end face of the contact cover 33 , for connection to an electrical wiring connected to the ECU 2 .
[0065] The switch coil 22 has a radially outer peripheral side on which an axial magnetic path member 39 is arranged to form a part of a magnetic path. Also the switch coil 22 has an axial side opposite to the fixed core, on which a radial magnetic path member 40 is arranged to form a part of the magnetic path.
[0066] The axial magnetic path member 39 has a cylindrical shape and is inserted into the switch yoke 25 along the inner periphery thereof with substantially no gap being provided therebetween. The axial magnetic path member 39 has an axial end face on the first end E 1 side, which axial end face is brought into contact with a radially outer end face of the fixed core 23 to determine the axial position of the member 39 .
[0067] The radial magnetic path member 40 is arranged perpendicular to the axis of the switch coil 22 . The radial magnetic path member 40 has a radially outer end face on the first end El side, which surface is brought into contact with an axial end face of the axial magnetic path member 39 to constrain the position of the member 40 with respect to the switch coil 22 . The radial magnetic path member 40 has a round opening at its radial central portion so that the movable core 32 can move therethrough in the axial directions AX.
[0068] The fixed core 23 is magnetized upon supply of current to the switch coil 22 . Then, the movable core 32 is attracted to the attractive surface S 2 of the fixed core 23 against the reaction force of the return spring 41 disposed between the fixed core 23 and the movable core 32 . When the current supply to the switch coil 22 is stopped, the movable core 32 is pushed back in the direction opposite to the fixed core 23 (rightward in FIG. 2 ) by the reaction force of the return spring 41 .
[0069] The contact cover 33 has a cylindrical leg portion 33 a. The leg portion 33 a is inserted into the switch yoke 25 along the inner periphery thereof, the switch yoke 25 forming a part of the overall yoke on the second end E 2 side. The contact cover 33 is arranged, with the end face of the leg portion 33 a being in contact with a surface of the radial magnetic path member 40 , and caulked and fixed to the open end, i.e. the second end E 2 , of the overall yoke.
[0070] The terminal bolt 34 , one of the two terminal bolts, is a B terminal bolt 34 to which a battery cable 42 (see FIG. 3 ) is connected. The terminal bolt 35 , the other of the two terminal bolts, is an M terminal bolt 35 to which a motor lead 43 (see FIGS. 1 and 3 ) is connected. The pair of fixed contacts 36 , which are provided separately from (or may be provided integrally with) the two terminal bolts 34 and 35 , are electrically in contact with the two terminal bolts 34 and 35 inside the contact cover 33 and mechanically fixed to the contact cover 33 .
[0071] The movable contact 37 is arranged so that the distance from the movable contact 37 to the movable core is larger than the distance from the pair of fixed contacts 36 to the movable core (rightward in FIG. 2 ). The movable contact 37 is in reception of the load of a contact-pressure spring 45 and pressed against an end face of a resin rod 44 fixed to the movable core 32 . It should be appreciated that the initial load of the return spring 41 is set larger than that of the contact-pressure spring 45 . Therefore, when the switch coil 22 is de-energized, the movable contact 37 is seated on an inner seat 33 b of the contact cover 33 , with the contact-pressure spring 45 being contracted.
[0072] The motor contact mentioned above is formed of the pair of fixed contacts 36 and the movable contact 37 . Being biased by the contact-pressure spring 45 , the movable contact 37 comes into contact with the pair of fixed contacts 36 with a predetermined pressing force. Resultantly, current is passed across the pair of fixed contacts 36 via the movable contact 37 to thereby dose the motor contact. When the movable contact 37 is drawn apart from the pair of fixed contacts 36 , the current across the pair of fixed contacts 36 is shut down to thereby open the motor contact.
[0073] a) Referring to FIGS. 4A to 4D and FIGS. 6 to 9 , an operation is described taking as an example a first situation in which engine restart is requested while the number of revolutions of the ring gear 3 is decreasing in an engine stop process.
[0074] FIG. 4A illustrates a process in which the pinion 19 moves forward to the ring gear 3 which is decreasing the number of revolutions. FIG. 4B illustrates a state where the end face 19 a of the pinion 19 is in contact with the end face 3 a of the ring gear 3 . FIG. 4C illustrates a process in which the positions of the pinion 19 and the ring gear 3 are relatively deviated in the direction of revolutions. FIG. 4D illustrates a state where the pinion 19 is brought into engagement with the ring gear 3 in a decelerating state.
[0075] FIG. 6 is a graph illustrating engine speed Neg in the engine stop process with time being indicated on the horizontal axis. In FIG. 6 , “X” indicates a point of generation of an engine stop signal, “Cm” indicates a point when an engine restart request is given by the driver's free will, “Sp” indicates an actuation start point of the pinion-pushing solenoid 8 , “δN” indicates relative numbers of revolutions of the ring gear 3 and the pinion 19 , and “Mp” indicates an actuation start point of the motor electrification switch 10 .
[0076] After generation of an engine stop signal at the point X of FIG. 6 , an engine restart request may be given by the driver at the point Cm. Then, the ECU 2 permits the RPM detector 4 to input the number of revolutions of the ring gear 3 at the time the request has been given. If the number of revolutions of the ring gear 3 is lower than a predetermined number of revolutions, the starter relay 30 is controlled and turned on at the point (point Sp of FIG. 6 ) when the relative numbers of revolutions of the ring gear 3 and the pinion 19 have reached δN. At this point, the number of revolutions of the motor 5 is “0” because the motor electrification switch 10 has not been actuated (no current is passed to the switch coil 22 ). Accordingly, the relative numbers of revolutions will be expressed as: δN=the number of revolutions of the ring gear 3 .
[0077] When the starter relay 30 is closed, current is supplied from the battery 9 to the solenoid coil 21 of the pinion-pushing solenoid 8 . Then, the plunger 27 is moved, being attracted to the magnetized fixed core 23 . With the movement of the plunger 27 , the pinion movable body (the clutch 18 and the pinion 19 ) is pushed in the direction opposite to the motor via the shift lever 7 . Then, as shown in FIGS. 4A and 4B , the pinion 19 moves forward to the ring gear 3 which is decreasing the number of revolutions. As a result, the end face 19 a of the pinion 19 is pressed against the end face 3 a of the ring gear 3 applied with a predetermined load F 1 . In this case, a rotational torque T 1 with which the ring gear 3 attempts to rotate the pinion 19 can be expressed by the following Formula (1):
[0000] T 1= F 1× rp×μ 1 (1)
[0000] where μ1 is a frictional coefficient between the end face 19 a of the pinion 19 and the end face 3 a of the ring gear, rp is a pitch circle radius of the pinion 19 (see FIG. 7 ).
[0078] In this case, a rotational torque T 2 of the clutch 18 in an idling state may be set smaller than the rotational torque T 1 (T 1 >T 2 ). Thus, the revolutions of the pinion 19 catch up and synchronize with the revolutions of the ring gear 3 . In this regard, at least either the end face 19 a of the pinion 19 or the end face 3 a of the ring gear 3 may be formed with a frictional coefficient increasing means, so that the frictional coefficient may be increased at each of the teeth of either the pinion 19 or the ring gear 3 .
[0079] For example, as shown in FIG. 8 , which is an illustration of the end face 19 a of the pinion 19 , a plurality of grooves 19 b may be formed in the end face 19 a. In this case, each of the grooves 19 b may have a depth which is smaller than a module of the pinion and the ring gear. Preferably, the depth is smaller than 1/n of the module (n is a positive integer of 9 or less). The module is defined as a size (i.e., height) of each tooth of each of the pinion and ring gear. Thus, the frictional force between the end face 19 a of the pinion 19 and the end face 3 a of the ring gear 3 will be increased when both of the end faces are brought into contact with each other. Accordingly, the revolutions of the pinion 19 can instantaneously synchronize with the revolutions of the ring gear 3 .
[0080] From the point of synchronization as well, the ring gear 3 still continues decreasing revolutions. However, since the clutch 18 is now on the connecting side (torque transmitting side), the rotational torque which is received by the pinion 19 from the ring gear 3 will be a torque T 3 that rotates the armature 14 of the motor 5 . FIG. 9 is a schematic diagram illustrating the configuration of the motor 5 with a brush. As shown in FIG. 9 , in the case where the brush 16 is pressed against the outer periphery of the rectifier 13 having a radius rc with a frictional coefficient μc, the rotational torque T 3 that rotates the armature 14 can be expressed by the following formula (2):
[0000] T 3= F 2× rc×μc (2)
[0081] In this case, the rotational torque T 3 for rotating the armature 14 may be set larger than the rotational torque T 2 of the clutch 18 in an idling state (T 3 >T 2 ). Thus, the frictional force caused between the end faces of the pinion 19 and the ring gear 3 will be smaller than the rotational torque T 3 that rotates the armature 14 . Therefore, the pinion 19 will not decrease the number of revolutions keeping synchronization with the revolutions of the ring gear 3 . Instead, as shown in FIG. 4C , the ring gear 3 will be deviated with respect to the pinion 19 in the direction opposite to the direction of revolutions (rightward in FIG. 4C ). As a result, as shown in FIG. 4D , each of the teeth of the pinion 19 is pushed between the teeth of the ring gear 3 to thereby achieve engagement between the pinion 19 and the ring gear 3 .
[0082] After completion of the engagement between the pinion 19 and the ring gear 3 and then after expiration of a predetermined time (point Mp of FIG. 6 ), the ECU 2 outputs a turn-on signal to the motor electrification switch 10 .
[0083] When current is passed through the switch coil 22 of the switch 10 , the movable core 32 is attracted to the fixed core 23 to allow the movable contact 37 to come into contact with the pair of fixed contacts 36 . Then, being biased by the contact-pressure spring 45 , the motor contact is closed. As a result, current is supplied from the battery 9 to the motor 5 to generate torque in the armature 14 . The torque is then transmitted to the output shaft 6 via the reduction gear 17 . Further, the torque of the output shaft 6 is transmitted to the pinion 19 via the clutch 18 . Since the pinion 19 has already been in engagement with the ring gear 3 , the revolutions of the pinion 19 , as they are, are transmitted to the ring gear 3 . In this way, as plotted with the broken line in the graph of FIG. 6 , the engine speed Neg increases, whereby the engine is restarted.
[0084] b) Referring to FIGS. 5A to 5D , an operation is described taking as an example a second situation in which engine restart is requested while the number of revolutions of the ring gear 3 is decreasing in an engine stop process.
[0085] In the second situation, when the pinion movable body (the clutch 18 and the pinion 19 ) is pushed to the ring gear side with the actuation of the pinion-pushing solenoid 8 , a chamfered portion 19 c formed in each of the teeth of the pinion 19 is caught by a chamfered portion 3 b formed in each of the teeth of the ring gear 3 . The chamfered portion 19 c of the pinion 19 and the chamfered portion 3 b of the ring gear are also examples of the recesses recited in claim 2 of the present invention. As shown in FIG. 5B , the chamfered portion 19 c is formed at a corner of each tooth of the pinion 19 , and the chamfered portion 3 b is formed at a corner of each tooth of the ring gear 3 . These chamfered portions (the recesses of the present invention) may be formed in either one of the pinion 19 and the ring gear 3 .
[0086] As shown in FIG. 5B , in the second situation, when each chamfered portion 19 c of the pinion 19 is caught by each chamfered portion 3 b of the ring gear 3 , the revolutions of the pinion 19 instantaneously synchronize with the revolutions of the ring gear 3 . In this regard, similar to the first situation, the rotational torque T 2 of the clutch 18 in an idling state is set smaller than the rotational torque T 1 that rotates the pinion 19 from the ring gear 3 side, while the rotational torque T 3 that rotates the armature 14 is set larger than the rotational torque T 2 of the clutch 18 in an idling state.
[0087] Even from the instant when the revolutions of the pinion 19 synchronize with the revolutions of the ring gear 3 , the number of revolutions of the ring gear 3 still continues decreasing. Accordingly, as shown in FIG. 5C , the ring gear 3 will be deviated with respect to the pinion 19 in the direction opposite to the direction of revolutions (rightward in FIG. 5C ). As a result, as shown in FIG. 5D , each of the teeth of the pinion 19 is pushed between the teeth of the ring gear 3 to thereby achieve engagement between the pinion 19 and the ring gear 3 . After completion of the engagement between the pinion 19 and the ring gear 3 and then after expiration of a predetermined time (point Mp of FIG. 6 ), the ECU 2 outputs a turn-on signal to the motor electrification switch 10 . Resultantly, the torque of the motor 5 is transmitted from the pinion 19 to the ring gear 3 , whereby the engine is restarted.
[0088] In the engine starting apparatus of the present invention, the pinion-pushing solenoid 8 is actuated to permit the end face 19 a of the pinion 19 to be in contact with the end face 3 a of the ring gear 3 . With this contact, the end face 19 a of the pinion 19 is pressed against the end face 3 a of the ring gear 3 with the predetermined load F 1 . Meanwhile, the rotational torque T 2 of the clutch 18 in an idling state is set smaller than the rotational torque T 1 with which the ring gear 3 in a decelerating state attempts to rotate the pinion 19 . Therefore, the revolutions of the pinion 19 can instantaneously synchronize with the revolutions of the ring gear 3 . As a result, engagement can be promptly established between the ring gear 3 and the pinion 19 .
[0089] According to the configuration and scheme described above, the expensive motor revolution control driver disclosed in WO2007/101770 will not be needed. Accordingly, the engine starting apparatus can be provided at low cost.
[0090] In the conventional art disclosed in WO2007/101770, the number of revolutions has to be fed back in permitting the number of revolutions of the pinion 19 to synchronize with that of the ring gear. However, with the engine starting apparatus of the present invention, the revolutions of the pinion 19 can be instantaneously synchronized with the revolutions of the ring gear 3 . Thus, the number of revolutions does not have to be fed back. In addition, when engine restart is requested while the number of revolutions of the ring gear is decreasing, the pinion 19 can be reliably brought into engagement with the ring gear to restart the engine in a short time.
[0091] The engine starting apparatus of the present invention is different from the conventional engine starting apparatuses using starters (i.e. the apparatuses in which the end face 19 a of the pinion 19 comes into contact with the end face 3 a of the ring gear 3 being applied with a predetermined load, and then engagement is forcibly established by the torque of the motor 5 ). Specifically, the engine starting apparatus of the present invention utilizes the inert revolutions (i.e., revolutions due to inertia) of the ring gear 3 in the engine stop process, for the engagement of the pinion 19 with the ring gear 3 . Therefore, the load imposed between the teeth of the pinion 19 and the teeth of the ring gear 3 is mitigated, exerting an effect of significantly reducing wearing between the ring gear 3 and the pinion 19 . Thus, the engine starting apparatus of the present invention can be appropriately used for an idle stop system in which the number of actuations of the starter 1 is significantly increased.
[0092] In the conventional engine starting apparatuses using starters, the pinion 19 has been brought into engagement with the ring gear that remains stationary, utilizing the torque of the motor 5 . Therefore, if the engagement is unsuccessful once, the relative numbers of revolutions of the pinion 19 and the ring gear 3 will be increased with time, no longer enabling engagement. In this regard, with the engine starting apparatus of the present invention, the revolutions of the pinion 19 are synchronized with those of the ring gear 3 during the process in which the number of revolutions of the ring gear 3 is decreasing, and then engagement is established. Thus, the relative numbers of revolutions of the pinion 19 and the ring gear 3 will be approximated with time, whereby engagement can be easily achieved. Accordingly, compared to the conventional engine starting apparatuses using starters, the engine starting apparatus of the present invention can significantly and highly reliably reduce the probability of failure of engagement between the pinion 19 and the ring gear 3 .
[0093] (Modifications)
[0094] In the embodiment described above, the starter relay 30 has been turned on to actuate the pinion-pushing solenoid 8 (at this point, current has not yet been supplied to the switch coil 22 of the motor electrification switch 10 ) under the conditions where: the number of revolutions of the ring gear 3 at the point when engine restart is requested is lower than a predetermined number of revolutions; and the relative numbers of revolutions of the ring gear 3 and the pinion 19 have reached δN (the number of revolutions of the ring gear 3 =δN). However, when the number of revolutions of the ring gear 3 at the point when engine restart is requested is higher than the predetermined number of revolutions, the switch 10 may be actuated prior to the actuation of the solenoid 8 , followed by actuating the solenoid 8 at the point when the relative numbers of revolutions of the ring gear 3 and the pinion 10 have reached δN. In this case, it is not required to wait for the number of revolutions of the ring gear 3 to become equal to or lower than the predetermined number of revolutions. Accordingly, engine restart can be carried out in a short time.
[0095] In this modification, the relative numbers of revolutions of the ring gear 3 and the pinion 19 can be determined based on the number of revolutions of the ring gear 3 detected by the RPM detector 4 , and a predetermined logic set according to an estimated ascending curve of the number of revolutions of the motor (rising curve of the motor 5 ). | In an engine starting apparatus, together with a one-way clutch, a pinion is pushed toward a ring gear of an engine mounted in a vehicle, The one-way clutch has an idling torque smaller than a torque of the ring gear that tries to turn the pinion when the pinion is pushed to the ring gear. By a control device, a pinion pushing device is enabled to operate when i) the revolution speed of the ring gear is larger than a revolution speed of the pinion and ii) a relative revolution speed between the revolution speed of the ring gear and the revolution speed of the pinion is a desired value. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to post heat-treatment metalworking of an alloy that has previously been strengthened in a heat treatment with reactive gasses. Specifically, the invention relates to exposing a subsequently metalworked portion of the previously strengthened substrate to reactive gasses during the subsequent metalworking process.
BACKGROUND OF THE INVENTION
[0002] The recent introduction of advanced high temperature alloys that are strengthened by reactive gas heat treatment poses significant advantages as well as limitations. An example, but not meant to be limiting, of such a material is NS-163™ manufactured by Haynes International of Kokomo, Ind., USA. As manufactured, this material is very ductile, formable, and weldable. After forming and weld fabrication assemblies are then given a high temperature nitrogen atmosphere heat treatment to optimize mechanical properties. In this material the heat treatment causes nitridation throughout the part and results in considerable strengthening. The strengthening mechanism is largely attributed to the precipitation of titanium and columbium nitrides. This processing has limitations, however. For example, heat treatment strengthening is limited to relatively thin substrates, e.g. about 2 mm (0.08″) maximum. Also, after fabrication and heat treatment the assembly cannot be further processed by forming or welding because it is fully strengthened and not amendable to such metalworking. However, there are occasions where it would be advantageous to form and/or metalwork the material subsequent to the heat treatment. Consequently, there remains room in the art for improvement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The invention is explained in the following description in view of the drawings that show:
[0004] FIG. 1 illustrates a full penetration metalworking process using reactive gas shielding.
[0005] FIG. 2 is a cross-sectional view of a repair made using the process of FIG. 1 .
[0006] FIG. 3 is a cross-sectional view of an assembly made using the process of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
[0007] The inventor has discovered an innovative method for re-strengthening an alloy, for example a cobalt or nickel based alloy, that has previously been strengthened via a gas reactive heat treatment, where the alloy has been subjected to a post strengthening metalworking that otherwise would reduce or eliminate the strengthening effect. Some post heat treatment metalworking processes, such as welding, have an effect of reducing or eliminating the strengthening effect resulting from the original heat treatment. It is thought that this happens when heat from the subsequent metalworking process reduces or eliminates precipitates that formed during the original heat treatment process. As a result, these precipitates may not be present in the portion of the previously strengthened substrate that has subsequently been metalworked, and so the portion of the substrate that has subsequently been metalworked may be weaker than a remainder of the substrate. The inventor has discovered that exposing the subsequently metalworked portion of the previously strengthened substrate to a reactive element that was present in the original strengthening process helps reform precipitates in the subsequently metalworked portion of the substrate. This re-strengthens the portion of the previously strengthened substrate that has subsequently been metalworked, leaving a substrate of uniform or near uniform strength.
[0008] In the case of Haynes NS-163™ alloy, the chemical composition of the substrate includes the elements titanium and columbium. When the NS-163™ alloy is heat treated in an atmosphere containing nitrogen the nitrogen combines with the titanium and/or columbium to form nitride precipitates throughout an entire volume of the NS-163™ alloy, and these precipitates strengthen the entire volume of the NS-163™ alloy. Conventional practice in metalworking alloys that are relatively reactive to the atmosphere requires that the metalworking be done in an inert environment. For example, argon and/or helium are typically used for shielding from the atmosphere during welding, cladding, or hardfacing stainless steels and alloys of nickel, cobalt, aluminum, and titanium. The objective of such shielding is to prevent excess oxidation and/or nitridation. For particular other reasons limited percentages of reactive (i.e. non-inert) shielding gasses are sometimes used or most especially combined with inert gasses. Certain processes, such as cladding or surface hardening, have used hydrogen as part of a metalworking atmosphere. However, the inventor is unaware of any full penetration metalworking process that utilizes a metalworking atmosphere that contains nitrogen in order to re-strengthen a substrate that has previously been strengthened through a heat treatment process utilizing a heat treatment atmosphere containing that same reactive element.
[0009] The method described herein can be used with various metalworking processes where a full thickness of the substrate is traversed by the metalworking process, e.g. a full penetration metalworking process, including but not limited to laser beam welding (LBW), plasma arc welding (PAW), tungsten inert gas (TIG) welding, and metal inert gas (MIG) welding etc. Such a full penetration welding process includes keyhole welding processes when joining two substrates edge-to-edge. As shown in FIG. 1 , in keyhole welding processes an entire thickness of a portion of the substrate 10 is melted via an energy source 11 into a molten pool 12 (a.k.a. weld pool), and a hole 14 is formed through the entire thickness of the molten pool 12 of the substrate 10 , and therefore an entire thickness of the substrate 10 itself. As the process traverses the substrate the molten pool 12 and associated hole 14 also traverse the substrate 10 in a direction of travel 15 . Molten substrate solidifies into a weld bead 16 behind the hole 14 . As the molten pool 12 heats and then melts previously hardened substrate material the strengthening effect that resulted from the heat treatment in the reactive gas atmosphere and indicated by strengthened region 18 diminishes or disappears altogether, as indicated by de-strengthened area 20 .
[0010] In the inventive process a full volume of the molten pool is exposed to the reactive element in the metalworking atmosphere 22 via a shielding gas delivery path 24 . The metalworking atmosphere 22 covers the top of the molten pool 12 and is also forced through the hole 14 . This entrains the reactive element within the molten pool 12 . This entrained reactive element then reacts with the elements in the substrate to strengthen the portion of the substrate that has been melted during the metalworking process. As the melted portion of the substrate cools the strengthening effect brought about by the reactive element begins to return, as indicated by first restrengthening region 26 , and once cooled the re-strengthened region 28 is fully re-strengthened to the level of the substrate 10 prior to the metalworking process. As a result, the entire volume of the substrate 10 , including that which was metalworked subsequent to the strengthening heat treatment, is strengthened to a uniform or near-uniform level.
[0011] The reactive element may also be delivered directly to a back side 30 of the weld as a backing gas 32 via a backing gas delivery path 34 during the metalworking process in order to entrain nitrogen in the molten material at the bottom of the weld pool, or molten material that has worked around to the back side 30 of the substrate. The reactive element may also be delivered to a solidified portion 36 of the subsequently metalworked portion as trailing gas 38 delivered via a trailing gas delivery path 40 so nitrogen may still be incorporated into a surface 42 of the solidified weld.
[0012] The nitrogen may likewise be delivered in various ways. For example, the nitrogen may be in gas form and independently delivered discretely or mixed with another gas to a molten pool. It may be a gas delivered discretely or mixed with another gas via a gas delivery path that is already incorporated into a welding process. Alternately it may be incorporated into a solid material such as a flux and released as a gas during the metalworking process.
[0013] When delivered independently to the molten pool, an existing metalworking process would simply need to be supplemented with a supply of nitrogen and a shielding gas delivery path 24 to deliver the nitrogen to the molten pool. When delivered by using an existing shielding gas delivery path 24 , the nitrogen may take the place of gasses that formerly occupied that shielding gas delivery path, or it may be mixed with those gasses. For example, in LBW the gaseous nitrogen may be delivered via the incorporated shielding gas path or the incorporated optical assist/protective gas path. In PAW the gaseous nitrogen may be delivered via the incorporated shielding gas path or the incorporated orifice gas path. In TIG and MIG welding the gaseous nitrogen may be delivered via the incorporated shielding gas path. The nitrogen may also be delivered via a backing gas delivery path 34 or a trailing gas delivery path 40 . When nitrogen is incorporated into a solid, for example a flux, it may be delivered in any manner acceptable for delivering a flux. For example, the nitrogen containing flux could be a coating on an electrode, or a delivered separately flux, such as a powder applied to the substrate prior to the metalworking process, or a powder mixed and delivered with or in place of powder flux conventionally used in the metalworking process.
[0014] Metalworking using the method disclosed herein may be used for a variety of purposes. For example, the method may be used in a welding process where two substrates are joined edge to edge. The method may also be used as a way to repair substrates, or as a way to build smaller substrates into larger assemblies.
[0015] When used to repair a component, as shown in FIG. 2 , a substrate 50 may have a crack or other unwanted imperfection that is removed by excavation etc, leaving a hole into which a repair piece 52 may be inserted. Both the substrate 50 and repair piece 52 would have already been subjected to a strengthening heat treatment. The repair piece 52 may be joined to the substrate 52 using the method described herein, and the resulting repaired component 54 would then have all the strength of an original component.
[0016] FIG. 3 shows an assembly 60 with a plurality of substrate sheets 62 . The assembly 62 indicates several ways the technique described herein may be applied to a repair or to creating a new, built-up new component. In terms of repair and as opposed to placing a repair piece 52 in a hole as disclosed in FIG. 2 , a repair could be made where the repair piece 64 is positioned in an excavation of an assembly 60 and welded into place. This technique requires that the weld fully penetrate the repair piece 62 , but it is not necessary that the weld fully penetrate the component 60 .
[0017] The method disclosed herein may also be used to build-up several smaller substrate sheets 62 into a larger assembly 60 . This can happen in any or all of a number of ways, including welding sheets 62 in layers to form a thicker assembly 60 , and welding sheets 62 edge-to-edge to an assembly 60 , or assemblies 60 edge-to-edge etc. To form a layered assembly 60 , a second substrate 66 may be placed on top of a first substrate 68 and welded thereto. The welding may occur at the second substrate edges 70 , or may occur through a substrate sheet, as indicated by weld 72 of third substrate sheet 74 , which was welded to the second substrate at third substrate edges 76 and at a region 78 of the third substrate sheet 74 not at the edges. A fourth substrate sheet 80 has been shown as welded edge-to-edge to the second substrate sheet 64 and layered to the first substrate sheet 68 . A fifth substrate sheet 82 has been to a sixth substrate sheet 84 to form a second mini assembly 86 that has been edge-to-edge welded to a first mini assembly 88 to form the assembly 60 . Any or all of these techniques, or any technique that applies the teachings herein, may be used to form a complex assembly 60 of substrate sheets 62 .
[0018] The present inventor has developed a technique for re-strengthening a previously strengthened substrate that has subsequently been metalworked. The technique utilizes existing technology in a way not yet practiced, and thus it will be easy to implement. Further, the method is inexpensive yet permits assembly and repair of materials in ways not previously possible, and thus it represents an improvement in the art.
[0019] While various embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions may be made without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | A method of metalworking a substrate ( 10 ) previously strengthened in a gas heat treatment to form precipitates throughout an entire volume of the substrate ( 10 ), where the precipitates have an active chemical element incorporated during the gas heat treatment. The method includes: melting a portion of the substrate ( 10 ) during a full penetration metalworking process to form a molten portion ( 12 ); generating a metalworking atmosphere ( 22 ) having a supply of an active chemical element in a gas state during the metalworking process; exposing the molten portion ( 12 ) to the metalworking atmosphere ( 22 ); and cooling the molten portion ( 12 ) while maintaining exposure to the metalworking atmosphere ( 22 ) to form a solidified portion ( 36 ) comprising precipitates comprising the active chemical element, where the precipitates are present throughout an entire volume of the solidified portion ( 36 ), and thereby re-strengthen the entire volume of the solidified portion ( 36 ). | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a hook for lockstitch sewing machine (with one needle thread and a bobbin thread), both of the rotary type and of the central bobbin type (known also as shuttle), and both for domestic and industrial use, which includes a tension spring improved compared to the state of the to make the thread tension during the sewing operation more constant and less sensitive to the type and diameter of the bobbin thread
[0002] The invention further relates to a lockstitch sewing machine comprising such a hook comprising such a tension spring improved compared to the state of the art to make the thread tension during the sewing operation more constant and less sensitive to the type and diameter of the bobbin thread.
BACKGROUND OF THE INVENTION
[0003] The improved tension spring can be used in place of the known tension spring, which depending on the executions is mounted on the bobbin case in case of a central bobbin hook, and on the bobbin case or directly on the basket in case of a rotary hook.
[0004] The rotary hook can be of the type with horizontal axis of rotation or of the type with vertical axis of rotation.
[0005] Lockstitch sewing machines and related central bobbin hooks or rotary hooks are well known and therefore will not be described here, limiting just to remember schematically their composition.
[0006] The central bobbin hook comprises a hook body on which is bound the bobbin case that contains the bobbin on which the bobbin thread is wound. The bobbin thread is threaded through the guiding holes of the bobbin case and is made to pass between the tension spring mounted on the bobbin case and the bobbin case itself, so as to create a tension on the thread during the unwinding of the same for the sewing operation. This tension can be adjusted by turning the adjusting screw of the tension spring.
[0007] Quite similar is the operation of the bobbin case—bobbin system in the rotary hooks, where the tension spring is always mounted on the bobbin case to create the tension of the bobbin thread, similarly as described for the central bobbin hook. The difference though is that on the rotary hooks, in execution with bobbin case, the bobbin case is constrained to the basket housed inside the hook body, instead directly to the hook body.
[0008] On the rotary hooks in execution without bobbin case, on the other hand, the bobbin is housed directly in the basket and the tension spring that creates the tension on the bobbin thread, is mounted on the basket and the bobbin thread is threaded through the guiding holes of the basket and is made to pass between the tension spring mounted on the basket and the basket itself so as to create a tension on the thread during the unwinding for the sewing operation. This tension can be adjusted by turning the adjusting screw of the tension spring.
[0009] Beyond where the tension spring is mounted (on the bobbin case or on the basket) its operating principle is always the same: the tension spring is formed by a thin metal sheet of a thickness generally between 0.2 mm and 0.5 mm, of elongated shape with a major axis a few times longer than the minor axis and bent appropriately at arch along its major axis, so as to press the bobbin thread on the wall of the support means on which the tension spring itself is mounted (respectively the bobbin case or the basket), thus creating a friction on the bobbin thread, which is then put under tension during unwinding for the sewing operation. The pressure with which the tension spring presses on the bobbin thread can be adjusted through an adjusting screw. Acting on this adjusting screw and varying the pressure, the bobbin thread tension is varied for the sewing. The tension spring is mounted on its support means (respectively the bobbin case or the basket) by means of said adjusting screw and a fastening screw or, alternatively to said fastening screw, by an interlocking system on the support means. Important for the thread tension's stability is the contact point between the tension spring and the bobbin thread. In the standard state of the art execution, this contact point is located on the edge of the tension spring. In absence of the bobbin thread it is in fact natural that the arch shaped bend of the tension spring leads said tension spring to rest on the support means, on which it is mounted, along the extremity of the tension spring that is on the edge of the sheet that constitutes it. In a second implementation (actually very rare), instead, the contact point is set back with respect to this edge and is determined by the point of tangency of the arc of bending of the tension spring and the profile of the support means on which the tension spring is mounted. In this case, however, it is much more difficult to identify with certainty the contact point, and it is much more difficult to keep constant the repeatability of such assembly during the mass production of the tension spring, which is always a thin bent metal sheet and as such presents discrete machining tolerances.
[0010] The first case, namely that of the pressure point corresponding to the edge of the tension spring's sheet is universally used and has the advantage of an easy realization. A first drawback, however, is constituted by the tension of the bobbin thread that is not stable (i.e. has oscillations) during the sewing operation as it is very dependent to the irregularities of the thread itself: pulling the thread by hand gives the feeling that the tension spring “scratches” the thread. This effect is much more evident with certain types of threads, such as those more rough and those of poor quality and is much more annoying when the sewing requires a low tension of the bobbin thread, as it causes irregularities in the closure of the stitch. A second disadvantage of this execution occurs when, at the change of the type of bobbin thread, also the tension generated by the pressure of the tension spring changes. Consequently, at each change of bobbin thread type is necessary to re-adjust the pressure, acting on the adjustment screw. This effect is obviously more inconvenient in applications that need a frequent change of the bobbin thread type, as occurs in household and handicraft activities.
[0011] The second case, namely that of the pressure point corresponding to the point of tangency of the arc of bending of the tension spring and the profile of the support means on which it is mounted, in part fixes the first mentioned disadvantage, as it reduces the fluctuations of the tension and reduces the tension's sensitivity to the irregularities and roughness of the bobbin thread. However, changing the diameter of the bobbin thread, also the pressure point can change, thus changing the tension. The main disadvantage of this second case, however, is given by the difficulty of mass production of such a tension spring and by a poor repeatability from one tension spring to another. These factors generate a much higher cost of production, in addition to a remaining intrinsic uncertainty concerning the exact point of pressure.
[0012] The U.S. Pat. No. 6,152,057 and U.S. Pat. No. 6,901,871 patents disclose a tension system in which the bobbin thread is wrapped at least partially around the element that generates the tension. The tension of the bobbin thread is therefore obtained by friction of the bobbin thread on the element that generates the tension.
[0013] The U.S. Pat. No. 6,895,879 patent describes a tension spring with a different section between the portion on which acts the adjustment screw and the portion on which the tension spring presses the thread. The purpose is to have a greater flexibility of the portion on which the tension spring presses the thread.
[0014] The CH-A-658 273 patent refers to a shuttle for textile machines and embroidery machines comprising a cover on which is fixed a flat spring arranged parallel on the cover and apt to give tension to the bobbin thread.
SUMMARY OF THE INVENTION
[0015] Purpose of the present invention is to provide a hook comprising a tension spring easy to produce, economic at least as the standard state of the art tension spring, but that creates a much more stable bobbin thread tension (i.e. with low fluctuations) during the sewing operation, as it is not subject to the irregularities of the thread itself: pulling the thread by hand must not give the feeling that the tension spring “scratches” the thread, but the thread must exit “smoothly”. A second advantage of the present invention occurs when, changing the type of bobbin thread, no or only a minimal difference of the tension occurs. Therefore, the change from one type of bobbin thread to another does not any more require to re-adjust the pressure of the tension spring by turning the adjusting screw.
[0016] This purpose has been achieved through the hook object of the independent Claim.
[0017] Further advantageous features are the subject of the dependent Claims.
[0018] Substantially, the hook according to the invention comprises a tension spring, mounted on the basket or on the bobbin case, which creates a friction on the bobbin thread independent as much as possible from the irregularities and from the characteristics of the thread, such as for example size, material, processing and surface roughness. In the following we indicate these better performances of the tension spring as more stable tension.
[0019] In a preferred embodiment, this more stable tension is achieved by a bending towards the outside (with respect to the support means on which it is mounted and with respect to the main bending radius of the tension spring) of the tension spring's extremity, so that the pressure point is no longer the edge of the spring, but the point of tangency of the radius of said bending of the tension spring's extremity. In this preferred embodiment, said bending radius of the tension spring's extremity is opposite to the main bending radius of the tension spring (which is bent towards the inside of the support means on which it is mounted), and is of very restrained size (typically of an order of magnitude less than the main bending radius of the tension spring).
[0020] In another preferred embodiment, the flat development of the tension spring's sheet, is extended in the proximity of the extremity of the tension spring designed to press on the bobbin thread, so to make possible to bend such excess material with a bending radius towards the outside (with respect to the support means on which the tension spring is mounted and with respect to the main bending radius of the tension spring) and to leave unchanged the contact point of the tension spring with the bobbin thread. The advantage, however, is constituted by the fact that while with the execution according to the state of the art, in this point falls the edge of the sheet of the tension spring, in the present invention, instead, in said point falls the point of tangency of the bending radius of the extremity.
[0021] In another preferred embodiment, said bending radius towards the outside of the extremity of the tension spring, opposite to the main bending radius of the tension spring (which is bent towards the inside of the support means on which it is mounted), is of a very small size and is less than 2 mm.
[0022] An advantage of the hook object of the present invention is constituted by the fact that it can be applied to all existing sewing machines without having to modify their stitching mechanism and without requiring any modification to a sewing machine available on the market, as a hook designed according to the invention is completely interchangeable with a conventional hook and possesses all the constructional features necessary to implement the invention.
[0023] Also the bobbin case or, respectively, the basket comprising the described tension spring, are object of the present invention and one of their advantage is that they can be mounted on all existing hooks without having to modify the hook and without requiring any changes to the hooks available on the market, as the bobbin case or, respectively, the basket made according to the invention are completely interchangeable with a bobbin case or, respectively, a basket, as they are known, and possess all the constructional features necessary to implement the invention.
[0024] Also the described tension spring is the object of the present invention and one of its advantage is the fact that it can be mounted on all the hooks, bobbin cases and baskets without having to modify the existing hooks, bobbin cases or baskets available on the market, as the tension spring according to the invention is completely interchangeable with a known tension spring and possesses all the constructional features necessary to implement the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention will now be described with reference to exemplary embodiments, but not limiting, described in the attached figures, where:
[0026] FIG. 1 shows schematically an exploded view of a central bobbin hook, complete with bobbin case, known;
[0027] FIG. 2 shows schematically an exploded view of a rotary hook with horizontal axis, complete with bobbin case, known;
[0028] FIG. 3 shows schematically an exploded view of a rotary hook with vertical axis, complete with bobbin case, known;
[0029] FIG. 4 shows schematically an exploded view of a rotary hook with vertical axis, in the execution without bobbin case, known;
[0030] FIGS. 5 a - 5 c , 6 a - 6 c and 7 a - 7 c show some of the embodiments of the tension spring according to the state of the art;
[0031] FIGS. 8 a - 8 c , 9 a - 9 c and 10 a - 10 c show a kind of embodiment of the tension springs of FIGS. 5 a - 5 c , 6 a - 6 c and 7 a - 7 c according to the invention, presenting a bending towards the outside (with respect to the support means on which it is mounted and with respect to the main bending radius of the tension spring), of the extremity of the tension spring, so that the pressure point on the bobbin thread is no longer the edge of the tension spring's sheet, but the point of tangency of the bending radius of said extremity;
[0032] FIGS. 11 a - 11 c and 12 a - 12 c show a different embodiment of the tension spring of FIGS. 8 a - 8 c according to the invention, in which the flat development of the tension spring's sheet is extended in the proximity of the tension spring's extremity designed to press on the bobbin thread, so as to make possible to bend such excess material with a bending radius towards the outside (with respect to the support means on which the tension spring is mounted and with respect to the main bending radius of the tension spring) and to leave unchanged the contact point of the tension spring with the bobbin thread. This different embodiment of the tension spring of FIGS. 8 a - 8 c according to the invention, that considers to extend the flat development of the tension spring's sheet in proximity of the extremity of the tension spring designed to press on the bobbin thread, is easily achievable also for the other described embodiments of the tension spring, but the graphical representation is here omitted, as it would not be significantly different from FIGS. 9 a - 9 c and 10 a - 10 c;
[0033] FIGS. 13 a - 13 c show the mere detail in section along the section line A-A of FIGS. 5 b , 8 b , 11 b of the point where the tension spring presses on the bobbin thread, by comparing a) the embodiment according to the state of the art in where the pressure point is on the edge of the sheet; b) the first embodiment according to the present invention in which the extremity of the tension spring is bent outwards generating a radius and moving back the point of pressure; c) the second embodiment according to the present invention in which the flat development of the tension spring has been extended so that when the additional material at the tension spring's extremity is bent towards the outside, the pressure point still remains the original one of the tension spring according to the state of the art.
DETAILED DESCRIPTION OF THE INVENTION
[0034] In the attached figures, corresponding elements will be identified by the same numeral references.
[0035] FIG. 1 shows schematically an exploded view of a central bobbin hook 11 with horizontal axis “a” of rotation, known, in which only the elements relevant to the present description have been identified by numeral references:
a hook body 2 , comprising a well 18 in which the bobbin case 8 complete with bobbin 4 is housed; a support means of the tension spring, in this case a bobbin case 8 housed in the well 18 of the hook body 2 , free to rotate inside of the hook body 2 and complete with latch slide 15 for the axial constraint of the bobbin case 8 on the hook body to prevent accidental disassembly during the sewing operation, and complete with the latch lever 16 that acting on the latch slide 15 allows the operator to disengage the slide 15 , and herewith the bobbin case 8 , from the axial constraint on the hook body 2 to allow the removal of the bobbin case, and complete with tension spring 9 to give tension to the bobbin thread (whose graphical representation is omitted) wound on the bobbin 4 which is inside the bobbin case 8 ; a bobbin 4 , on which is wound the bobbin thread (not shown), is housed in the bobbin case 8 and is constrained within the hook body 2 by the mounting of the bobbin case 8 on the hook body 2 .
[0039] FIG. 2 shows schematically an exploded view of a rotary hook 12 with horizontal axis “α” of rotation, known, in which are identified by numeral references only the elements relevant for the purposes of the present description:
a hook body 2 ; a basket 6 , free to rotate inside of the hook body 2 comprising: a well 18 of the basket 6 in which is housed the bobbin case 8 complete with bobbin 4 ; a support means of the tension spring, in this case a bobbin case 8 housed in the well 18 of the basket 6 , complete with latch slide 15 for the axial constraint of the bobbin case 8 on the basket to prevent accidental disassembly during the sewing operation, and complete with the latch lever 16 that acting on the latch slide 15 allows the operator to disengage the slide 15 , and herewith the bobbin case 8 , from the axial constraint on the basket 6 to allow the removal of the bobbin case, and complete with tension spring 9 to give tension to the bobbin thread (whose graphical representation is omitted) wound on the bobbin 4 which is inside the bobbin case 8 ; a bobbin 4 , on which is wound the bobbin thread (not shown), is housed in the bobbin case 8 and is constrained within the basket 6 by the mounting of the bobbin case 8 on the basket 6 .
[0044] FIG. 3 shows schematically an exploded view of a rotary hook 13 with vertical axis “α” of rotation, known, in which are identified by numeral references only the elements relevant for the purposes of the present description:
a hook body 2 ; a basket 6 , free to rotate inside of the hook body 2 comprising: a well 18 of the basket 6 in which is housed the bobbin case 8 complete with bobbin 4 ; a lever 16 that allows the operator to disengage the bobbin case 8 , from the axial restraint on the basket 6 to remove the bobbin case 8 ; a support means of the tension spring, in this case a bobbin case housed in the well 18 of the basket 6 , complete with tension spring 9 to give tension to the bobbin thread (whose graphical representation is omitted) wound on the bobbin 4 which is inside the bobbin case 8 ; a bobbin 4 , on which is wound the bobbin thread (not shown), is housed in the bobbin case 8 and is constrained within the basket 6 by the mounting of the bobbin case 8 on the basket 6 .
[0049] FIG. 4 shows schematically an exploded view of a rotary hook 14 with vertical axis “α” of rotation, in execution without bobbin case, known, in which are identified by numeral references only the elements relevant for the purposes of the present description:
a hook body 2 ; a support means of the tension spring, in this case a basket 6 , free to rotate inside the hook body 2 , comprising: a well 18 of the basket 6 in which is housed the bobbin 4 , a lever 16 that allows the operator to disengage the bobbin 4 from the axial constraint on the basket 6 to allow the removal of the bobbin, and a tension spring 9 to give tension to the bobbin thread (whose graphical representation is omitted) wound on the bobbin 4 ; a bobbin 4 , on which is wound the bobbin thread (not shown), housed inside the basket 6 .
[0053] FIGS. 5 a - 5 c , 6 a - 6 c and 7 a - 7 c show different tension springs in the version according to the state of the art in a perspective view a) and in a side view b), with the detail c) zoomed and in section according to the axis A-A to highlight the pressure point P of the tension spring on the bobbin thread.
[0054] The hook 11 , 12 , 13 , 14 object of the present invention, comprises a tension spring, mounted on the basket or on the bobbin case, which creates a stable tension on the bobbin thread and independent as much as possible from the irregularities and from the characteristics of the thread.
[0055] In a preferred embodiment of a hook 11 , 12 , 13 , 14 according to the invention, described in FIGS. 8 a - 8 c , 9 a - 9 c and 10 a - 10 c , the tension spring designed to create such a stable tension comprises a bending towards the outside (with respect to the support means on which it is mounted and with respect to the main bending radius of the tension spring) of the extremity of the tension spring, so that the pressure point is no longer the edge of the tension spring's sheet, but the point of tangency of the radius of said bending extremity of the tension spring. In this preferred embodiment, said bending radius of the tension spring's extremity is opposite to the main bending radius of the tension spring (which is bent towards the inside of the support means on which it is mounted), and is of very small size (typically of an order of magnitude less than the main bending radius of the tension spring).
[0056] FIGS. 8 a - 8 c , 9 a - 9 c and 10 a - 10 c show a first preferred embodiment of the present invention. In the version according to the state of the art, the tension spring ( 50 , 60 , 70 ) comprises an edge at its extremity, which generates the pressure point P on the bobbin thread. In the execution according to said first preferred embodiment of the present invention, the tension spring ( 80 , 90 , 100 ) comprises a bending towards the outside at its extremity, whose bending radius R is designed to press on the bobbin thread.
[0057] FIGS. 11 a - 11 c and 12 a - 12 c show a second preferred embodiment of the present invention. As said, in the version according to the state of the art, the tension spring ( 50 ) comprises an edge at its extremity, which generates the pressure point P on the bobbin thread. In the version according to said second preferred embodiment of the present invention, the tension spring ( 110 , 120 ) comprises an extension of the flat development of the tension spring's sheet, in the proximity of the extremity of the tension spring designed to press on the bobbin thread, so as to make possible to bend such excess material ( 111 , 121 ) towards the outside (with respect to the support means on which the tension spring is mounted and with respect to the main bending radius of the tension spring) with a bending radius R and to leave unchanged the contact point of the tension spring with the bobbin thread. Quite evident corresponding extensions can be realized for the other embodiments of the tension spring according to the state of the art ( 60 , 70 ), for which the representation is omitted.
[0058] FIGS. 13 a - 13 c show the mere detail in section along the section line A-A of the tension springs ( 50 , 80 , 110 ) of the previous FIGS. 5 b , 8 b , 11 b of the point P where the tension spring presses on the bobbin thread, by comparing a) the embodiment of the tension spring 50 according to the state of the art where the pressure point is on the edge of the sheet; b) the first embodiment of the tension spring 80 according to the present invention in which the extremity of the tension spring is bent towards the outside generating a radius R and moving back the pressure point P with respect to the original one of the tension spring 50 according to the state of art; c) the second embodiment of the tension spring 110 according to the present invention in which the flat development of the tension spring has been extended so that when the additional material 111 at the tension spring's extremity is bent towards the outside, the pressure point remains in the same position as the original one of the tension spring 50 according to the state of the art. Entirely analogous considerations apply to other embodiments of the tension spring ( 60 , 70 ).
[0059] In another preferred embodiment, said bending radius R towards the outside of the tension spring's extremity, opposite to the main bending radius of the tension spring (which is bent towards the inside of the support means on which it is mounted), is of a very small size and is less than 2 mm.
[0060] The hooks according to the invention, therefore, vary from those according to the state of the art ( 11 , 12 , 13 , 14 ) only for the use of the tension spring ( 80 , 90 , 100 , 110 , 120 ) designed according to one of the preferred embodiments.
[0061] Naturally, the invention is not limited to the particular embodiments previously described and illustrated in the attached figures, but it can be subject to numerous modifications of detail within the reach of a person skilled in the art, without departing from the scope of the invention itself, as defined in the appended claims. | Hook ( 11, 12, 13, 14 ) for a lockstitch sewing machine, or parts of the hook such as the support element of the tension spring (in particular the basket or the bobbin case) or the tension spring itself, including a tension spring ( 80, 90, 100, 110, 120 ) that includes a bending towards the outside (with respect to the support element on which it is mounted and with respect to the main bending radius of the tension spring) of the tension spring's extremity designed to press on the bobbin thread, so that the pressure point (P) on the bobbin thread is the point of tangency between the bending radius (R) of the bending of the tension spring's extremity and the support element of the tension spring, so as to generate a stable tension of the bobbin thread. | 3 |
FIELD OF THE INVENTION
The present invention relates to the field of source light determination and more particularly to an apparatus and an associated method for discriminating among various types of light sources, such as fluorescent light, incandescent light, mixed light, and natural daylight.
BACKGROUND OF THE INVENTION
To produce faithful photographic reproductions of multicolored scenes, the color balance of the photographic film must be compatible with the spectral characteristics of the scene illuminant. Many photographic color emulsions are color balanced for use with natural daylight and others are color balanced for use with incandescent illumination. To properly expose a color film with an illuminant for which the film is not color balanced it is necessary to use color compensating filters. Alternatively, correction can be made during the printing stage. When such compensation is automatically provided by the camera, by engaging the proper filter or by marking the film with a printing instruction, it is necessary to have some automatic technique for discriminating among various types of light sources.
A patent of interest for its teaching of a method and apparatus for discriminating illuminant light is U.S. Pat. No. 4,220,412, entitled "Illuminant Discrimination Apparatus and Method" by R. A. Shroyer, et al. The method and apparatus disclosed in that patent utilizes the temporal signatures of the various light components based upon the peak amplitude and the harmonic distortion in the sine wave signal that is derived from the illuminant source impinging on a photodiode. The photodiode produces an electrical signal having an amplitude which varies with the instantaneous intensity of the illuminant. The apparatus includes flicker ratio detecting circuitry which is capable of discriminating between pure fluorescent light, pure incandescent light and pure daylight. The flicker ratio is the ratio of the brightest to the dimmest intensities of the light during a given time interval. Natural light, like other light emanating from a source of constant brightness, has a flicker ratio of unity. Artificial light sources, being energized by ordinary household line voltage, have a brightness which flickers at approximately 120 Hz, twice the frequency of the line voltage. Owing to the different rates at which the energy-responsive elements of incandescent and fluorescent lamps respond to applied energy, such illuminance can be readily distinguished by their respective flicker ratio. A circuit also detects the amount of harmonic distortion in the signal. Using the harmonic content, it is further possible to distinguish incandescent light from fluorescent light mixed with daylight and to detect which light source is predominant in a mixture of fluorescent and incandescent light.
With the general interest in digital systems, it is useful to incorporate illuminant discrimination into a digital environment. This is done in U.S. Pat. No. 4,827,119, which discriminates among various types of illuminants such as fluorescent light, tungsten light and natural daylight. The apparatus is comprised of an analog portion and a digital portion. The analog portion functions to convert incident light into a conditioned analog signal. The digital portion utilizes an analog-to-digital converter and a microprocessor to perform a Fourier series analysis on one or more of the harmonics of the illuminant signal. The microprocessor compares the amplitudes of the harmonics against the amplitudes of known illuminant sources to identify the source.
In certain situations it is desirable to separate scenes having a dominant illuminant from scenes having mixed illumination with no single dominant illuminant. In U.S. Pat. No. 5,037,198, mixed illuminant detection is added to the choice of illuminant categories to take care of the cases where one illuminant is not dominant. In such cases, color correction is best handled by printing algorithms. Boundary conditions are used, based on thresholding, to eliminate detection errors seen when fluorescent illumination mixes with certain quantities of daylight and otherwise causes a tungsten reading. The apparatus is comprised of a means for converting illuminate light into corresponding electrical signals. The electrical signals are then directed to a log amplifier wherein they are compressed to form a signal approximately equal to the log of the DC term plus a ratio of the dominant AC components to the DC components. A second portion of the apparatus receives the signals from the log amplifier and provides two filtered outputs which are multiples of the frequency of expected artificial illumination sources. Each of the output signals is compared against a plurality of threshold signals to identify which illuminant components are present. The combination of detected components are then compared against the components of known illumination sources with the closest match identifying the unknown source. Means are provided for combining the output signals from both of the filters to identify mixed sources.
The methods employed in U.S. Pat. Nos. 4,827,119 and 5,037,198 examine the frequency of flicker in the light intensity spectrum and determine from the frequency harmonics which type of illumination is being used. A problem has arisen because new fluorescent lighting systems use power inverters to increase the frequency of operation and the efficiency of the light sources. With such high efficiency fluorescent illumination, it is difficult to detect these higher frequencies, which are as high as 70 kHz, due to speed limitations in the circuit topologies typically used in amplification of the signal generated by the photodiode detector. Because the ripple amplitude is diminished at such frequencies, using boundary conditions such as described in U.S. Pat. No. 5,037,198 would detect such lighting as mixed lighting. The color of such light, however, is closely related to the color of fluorescent light, and it would be desirable to detect high efficiency lighting as such.
SUMMARY OF THE INVENTION
The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to one aspect of the present invention, an illuminant discriminator comprises a photodetector for converting an impinging illuminant into an analog signal and a high pass filter coupled to the photodetector, wherein the high pass filter has a cutoff frequency selected to separate signal components due to high efficiency light which are then detected to indicate the presence of such lighting.
In a further embodiment, the high pass filter includes a first section with a first cutoff characteristic selected to pass signal components due to various types of lighting including high efficiency lighting, and a second section with a second cutoff characteristic selected to separate signal components due to high efficiency lighting from signal components due to other types of lighting. The type of illumination is then discriminated based on activation of the different filter sections such that tungsten and fluorescent lighting can be distinguished by the first section, and when mixed lighting is indicated by the first section then high efficiency lighting can be distinguished from mixed lighting by the second section.
The advantage of the invention is that a photodiode amplifier for camera photometer applications capable of detecting known flicker frequencies can additionally detect new high efficiency lighting by changing its input frequency response. This is specifically done by means of a high pass filter that exhibits different frequency responses based on the state of one or more analog switches. This can be done without substantially modifying the circuit topology of the amplifying section.
These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described in relation to the drawings, in which
FIG. 1 illustrates in block diagram a preferred apparatus implementation of the present invention;
FIG. 2 is a chart illustrating the performance characteristics of the apparatus of FIG. 1;
FIGS. 3A, 3B, 3C, and 3D illustrate in logic circuit form one set of combinational logic that may be used with the preferred apparatus implementation of FIG. 1; and
FIG. 4 is a frequency spectrum diagram of various light sources showing cut-off characteristics of filters used with the preferred apparatus implementation of FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, illuminant light is detected with a photodiode 2 to provide an electrical signal which is a function of the spectral content of the illuminant light. The photodiode 2 responds to incident light by producing a voltage that is logarithmically related to the intensity of light impinging thereon. When the light is from an artificial source, such as a fluorescent or incandescent lamp driven by a line voltage operating at a predetermined frequency, the photodiode produces a voltage having a DC component (or average value) proportional to the average light intensity and an AC component having a fundamental frequency that is proportional to twice the frequency of the line voltage (i.e., twice a conventional household line frequency of 60 Hz, for a fundamental of 120 Hz). In addition, as explained in U.S. Pat. No. 4,220,412 (which is incorporated herein by reference), the brightness curve of the fluorescent source contains more harmonic distortion (i.e., distortion due to the presence of harmonic frequency components other than the fundamental) than does the incandescent source.
As a special feature of the invention, the signal from the photodiode 2 is processed by a switched high pass filter 4. The switching portion includes analog switches 6 and 8 connected to switching lines A' and B', respectively, to connect either capacitor 10 or capacitor 12 into the high pass circuit. An operational amplifier 14 is connected as a high pass filter with a feedback resistor 16 and a voltage divider network 18 connected to a reference voltage V ref .
FIG. 4 shows the frequency response envelopes, designated as filter response 1 and filter response 2, of the switched high pass filter 4 relative to the normalized filter frequency spectrum for different light types, including tungsten, fluorescent, and high efficiency lighting. In the preferred embodiment, for suitable resistances 18, these envelopes are obtained by selecting a 0.2 μf capacitor and a 0.001 μf capacitor for capacitors 10 and 12, respectively. Switching lines A' and B' are activated by a processor 19a in response to an indication from a combinational logic section 19b, which includes the logic circuits shown in FIGS. 3A, 3B, 3C, and 3D. By activating analog switch 6 to select capacitor 10, the filter response 1 is obtained with a cutoff frequency (at 3 dB down) of about 50 Hz; and by activating analog switch 8 to select capacitor 12, the filter response 2 is obtained with a cutoff frequency (at 3 dB down) of about 10 kHz. It is important that filter response 1 includes all lighting and filter response 2 effectively eliminates fluorescent and tungsten lighting.
Returning to FIG. 1, the output signal from the switched high pass filter 4 is compressed by a logarithmic amplifier 20. The output signal from logarithmic amplifier 20, given the relative amplitudes of the various frequency components of the input signal as processed by the switched high pass filter 4, is approximately equal to a log of the DC term plus a ratio of the dominant AC components to the DC components. Several AC:DC ratios are present at the output of the log amp 20, in particular a fundamental AC/DC ratio and a second harmonic AC/DC ratio. As explained in U.S. Pat. No. 5,037,198, which is incorporated herein by reference, the output of the log amp 20 is a discriminator signal having a collection of harmonic components that can be mapped into the coordinate system shown in FIG. 2, which shows the performance of the system in terms of AC/DC amplitude ratios. The amplitude of each harmonic component, as explained in the '198 patent, is a measure of the type of illumination present.
An A/D converter 22 receives on its input the discriminator signal from the output of the log amp 20 and operates upon the analog discriminator signal to provide a corresponding digital signal at its output. The digitized signal is then directed to a microprocessor 26, which is programmed as a digital filter to perform the filtering and comparing operations shown within the broken line 24. In doing so, the microprocessor 26 operates upon the fundamental frequency component and one or more harmonic components of the digitized input signal and determines from evenly spaced samples the fundamental frequency and the second harmonic (as well as passing undersampling artifacts from higher frequencies, see below). The amplitudes of each frequency are determined by the square root of the squares of the sine and cosine terms. As described in the aforementioned U.S. Pat. No. 4,827,119, which is incorporated herein by reference, it is convenient to determine the fundamental frequency and the second harmonic from 8 samples spaced 1.042 ms. apart, assuming 60 Hz line frequency. Clearly, such a sampling frequency is far too low to reproduce a high efficiency lighting waveform. However, the sampling rate appropriate for tungsten and conventional fluorescent lighting produces enough sampling artifacts (due to undersampling) within the frequency spectrum represented by FIG. 2 to provide the basis, according to the invention, for distinguishing high efficiency lighting from other lighting.
The digitized discriminator signal is filtered by a 240 Hz digital filter 30 and a 120 Hz digital filter 40. The outputs of the filters 30 and 40 thus correspond to the coordinates in FIG. 2. The filter outputs are processed by comparator stages 50A-50G. Each of the comparator stages receives a threshold reference Vr1-Vr6. The reference values assigned to Vr1-Vr6 are determined from the chart of FIG. 2. The stage 50C receives the output signals from both filters 30 and 40 with the output from the 240 Hz filter 30 being boosted in gain by a factor of 8 in a gain stage 45. The comparator stages 50A and 50B form a first comparing means. A second comparing means is formed by comparator stages 50D through 50G, and comparator stage 50C along with gain stage 45 form a third comparing means. Although various types of logic functions can be used to form the desired outputs from the outputs A-G, the preferred logic is illustrated in FIGS. 3A-D. As can be seen in FIGS. 3A-3C, daylight requires both a B and a D input. Tungsten requires a C and an F input but not E, and fluorescent takes not A, not C, and not G.
The foregoing logic combinations are obtained with the analog switch 6 set to include capacitor 10 in the switched high pass filter 4; that is, filter response 1 (FIG. 4) is used, and, under that condition, all other input combinations reflect a mixed illuminant. The logic combination of FIG. 3D is used when the analog switch 8 is set to include capacitor 12 in the switched high pass filter 4; that is, filter response 2 is used, and high efficiency illumination is isolated. Under that condition, high efficiency illumination requires a not B and not D.
FIG. 2 illustrates, for filter response 1, the data taken from several light sources plotted such that the 120 Hz/DC ratio is the ordinate axis and the 240 Hz/DC ratio is the vertical axis. The boundary regions for mixed, fluorescent, daylight and tungsten illumination are also illustrated in FIG. 2. The daylight region (area) is defined by the voltage values Vr2 and Vr3 which exists around the (0,0) region. The tungsten region is defined by Vr4, Vr5 and a dotted gain line. The mixed regions are set off by Vr1, Vr6 and the dotted gain line. In the mixed regions there are additional data, where there is no predominant illuminant category present. A diagonal boundary condition which is formed by the X8 diagonal gain line of amplifier 45 further defines the mixed region, particularly relative to tungsten light. Moreover, there is a lower limit on the ratio 240 Hz:120 Hz. For the purposes of an easy implementation, the slope of 1:8 was chosen since it results in a low percentage of tungsten falling into the mixed region; however, this ratio may be a little smaller for optimum discrimination. Although there are no line harmonics present in daylight lit scenes, there is a possibility of dominantly daylight lit scenes so a region close to the origin has been set aside as daylight. Finally, note in particular that sampling artifacts due to undersampled high efficiency data are found within the frequency spectrum shown in FIG. 2. These sampling artifacts are not shown in FIG. 2 as one of the primary flicker components, but are understood to be present in the spectrum.
In operation, the illuminant discriminator is initially set to filter response 1 by activation of the analog switch 6 from the processor 18a. If the resulting data indicates, by use of combinatorial logic in FIGS. 3A to 3C, the presence of mixed lighting (i.e., all outputs are FALSE), then the logic section 19b commands the processor 19a to deactivate analog switch 6 and activate analog switch 8, thereby setting the illuminant discriminator to filter response 2. The high cutoff frequency (10 kHz) substantially eliminates the low frequency flicker components (as shown in FIG. 2) and any remaining component will be indicative of sampling artifacts due to high efficiency lighting. The combinatorial logic of FIG. 3D will detect such remaining artifacts due to high efficiency lighting, and the logic circuit 19b will provide a corresponding output. (Alternatively, a separate line 52 can be used from the A/D converter 22 to test for high efficiency lighting, since any signal component that is detected for filter response 2 is indicative of high efficiency lighting.) If filter response 2 provides no substantial output, mixed lighting is assumed and correction is left to printing.
This technique does not limit itself to one particular method of implementation. The block diagram of FIG. 1 illustrates the preferred embodiment, implemented with comparator stages in a digital system. Such a digital implementation is shown in the aforementioned U.S. Pat. No. 4,827,119, which is incorporated herein by reference. Frequency components listed are those seen in regions where 60 Hz power grids are used but they can be extended by replacing 120 Hz with the 2nd harmonic of the line frequency and 240 Hz with the 4th harmonic, etc.
While there has been shown what is considered to be the preferred embodiment of the present invention, it will be manifest that many changes and modifications may be made therein without departing from the essential spirit of the invention. It is intended therefore, in the annexed claims to cover all such changes and modifications as may fall within the true scope of the invention. Moreover, the separate filter responses could be achieved by using two separate high pass filters, although it is desirable from the standpoints of circuit size and cost to devise a single circuit as shown in FIG. 1 which can be configured to alter the frequency response.
______________________________________PARTS LIST______________________________________ 2 PHOTODIODE 4 SWITCHED HIGH PASS FILTER 6 ANALOG SWITCH 8 ANALOG SWITCH10 CAPACITOR12 CAPACITOR14 OPERATIONAL AMPLIFIER16 FEEDBACK RESISTOR18 VOLTAGE DIVIDER19a PROCESSOR19b LOGIC CIRCUIT20 LOG AMP22 A/D CONVERTER24 FILTERING AND COMPARING OPERATIONS26 MICROPROCESSOR30 240 Hz FILTER40 120 Hz FILTER45 GAIN STAGES50A-50G COMPARATOR STAGES52 LINE______________________________________ | An illuminant discriminator distinguishes a range of separate illuminants, including high efficiency fluorescent lighting, by modifying the frequency response of a signal output from a photodetector. A switchable high pass filter coupled to the photodetector has a first filter section with a first cutoff characteristic selected to pass signal components due to various types of lighting including high efficiency lighting, and a second section with second cutoff characteristic that separates out the high efficiency components. The high pass output is processed by a log amplifier to develop flicker frequency harmonics that are distinguished as to source illuminant by comparator stages. Undersampling artifacts due to high efficiency lighting are present in the mixed illuminant spectrum when the first filter section is operative, and positively identified as high efficiency lighting when the second section is operative. Consequently, when mixed illuminants are discriminated by the first section, they are further tested for a high efficiency source in the second section. | 6 |
FIELD OF THE INVENTION
The present invention relates to a method and system for greatly extending the effective coherence length of multimode non-stabilized lasers used in interferometric devices, which allows one to construct inexpensive interferometers with large optical path differences based on such lasers. Of particular interest is the application of this method of displacement measurement interferometry.
BACKGROUND OF THE INVENTION
Accurate measurement devices are needed by modern manufacturing facilities where the machining accuracy approaches several microns per meter so that the accuracy of the measuring devices for inspection and control must be in the sub-micron range. Among the existing measuring systems only interferometers can provide such accuracies over extended ranges (up to and beyond 1 meter). Other systems suffer either from limited accuracy or from limited range. Most commercial interferometers, which are capable of measuring ranges up to and above 10 meters and of accuracies of 0.1 μm/m or better, are based on stabilized lasers and are too delicate or too expensive to be used widely on the factory floor or be incorporated in systems for closed-loop motion control. Interferometers based on non-stabilized lasers, on the other hand, have a very limited measuring range.
The main obstacle to the use of non-stabilized lasers in displacement measuring interferometry (and in unequal-path interferometers in general) is their limited coherence length and, hence, limited measuring range. This is caused by simultaneous presence of several resonating cavity modes in laser emission (mode competition). Each of the modes forms its own interference fringe system, and these systems are shifted with respect to each other in accordance with the frequency difference between the modes and with the measured path length. The optical signal arriving at the detection system of an interferometer carries the interference fringe systems associated with each mode and, thus, can be regarded as "encoded" with the optical signals of the individual modes. The interference systems of different modes overlap incoherently because of a very large frequency difference between the modes compared with the frequency response of the detectors. Therefore, the fringe picture observed by the detection system is a sum of the fringe intensities of all the modes present, and the "encoded" information pertaining to the individual modes is lost.
Consider, for clarity, a short-tube laser which emits most of the time in two modes. The frequency spacing of the modes is c/2L, where L is the tube length of the laser. (This is illustrated in FIG. 1a, where the P 2 mode is, typically, below the gain threshold and does not participate in emission). If the optical path difference in the interferometer is equal to the tube length, then the fringe pictures of the two modes at detection are exactly in antiphase. This will be observed as a fringe picture of the stronger mode with fringe contrast reduced by the contamination by the second mode. If, in addition, the intensities of the modes are equal (FIG. 1b), then the loss of contrast will be complete. The intensities of the modes depend on their relative positions under the Doppler profile of the laser emission line (FIG. 1) and, in turn, on the laser tube length, and they fluctuate with inevitable fluctuations of the latter caused mainly by temperature variations. Thus, when the optical path difference approaches the tube length (i.e., when the displacement to be measured approaches its half) and the fringe systems of the two modes are in antiphase, partial loss of contrast will be observed and the contrast will fluctuate with time between almost 100% in the case of FIG. 1a and zero in the case of FIG. 1b. The coherence length of such a laser is equal, therefore, to its tube length.
In general, the coherence length of a multimode non-stabilized laser is 2L/m, where m is the number of modes, and in practice measuring ranges for, say, HeNe lasers, are only of the order 100 mm.
SUMMARY OF THE INVENTION
The present invention relates to a method for greatly extending the effective coherence length of a two-mode non-stabilized laser in a two-beam interferometer based on decoding of the individual optical signals pertaining to the fringe systems of the individual modes and utilization of the stronger signal for fringe counting. We refer to this method as a method of "count switching," since the counting of fringes is switched from one mode to another whenever necessary. This method allows one to build inexpensive interferometers with extended optical path differences which are equivalent to that of stabilized lasers (greatly exceeding the laser tube length) and are limited theoretically only by the width of an individual mode. An additional advantage of the count-switching interferometer is its improved accuracy compared with conventional systems. The method is directly applicable to multimode lasers as well.
DRAWINGS
FIGS. 1a, 1b, 1c are graphs which illustrate the mode competition and mode drift with changes of the laser tube length.
FIG. 2 is a block diagram of a count switching interferometer with mode separation at detection.
FIG. 3 is an optical scheme of an embodiment of the count switching interferometer with polarization mode separation at detection.
FIG. 4 is a block diagram of the count-switching electronics.
FIG. 5 illustrates the use of the count-switching interferometer as a measuring device in accurate closed-loop control of the motion of a translation stage.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a method and system for greatly extending the effective coherence length of non-stabilized lasers used in two-beam interferometric devices. The method is first described for a two-mode laser and then is extended to multimode lasers.
The method, which is the subject of the present invention, is designed to overcome the mode competition problem referred to above and amounts to separation of the fringe systems of the two modes in the total interferometric signal prior to detection (decoding of the individual mode signals in the total signal) and use of the stronger mode for fringe counting. As a result, there is no contamination of the fringe picture by that of the second mode (and, hence, no loss of contrast), and the intensity of the mode used for counting is always above a certain minimum. Therefore, the effective coherence length of the laser in the interferometer is greatly increased. In addition, there is a significant increase of accuracy compared with a conventional interferometer using a non-stabilized laser.
A block diagram illustrating the present invention is shown in FIG. 2 for the Michelson-type optical arrangement. There, (201) is the beam emitted by a two-mode non-stabilized laser; (202) is a beamsplitter separating the original laser beam into two beams: a reference beam (203) and a measuring beam (204); (205) and (206) are mirrors which reflect the beams (203) and (204) in order to recombine them in the interference beam (207); (208) is a mode separating component, which splits the interference beam (207) into two beams (209) and (210) each carrying the interference picture of a separate individual mode; (211) and (212) are electro-optical counting detectors producing fringe counts for each mode whenever possible; and (213) is the mode selector, which passes the counts of the optimum mode to the main counter (214).
In general, decoding (separation of the signals of the individual modes at detection) can be made on the basis of polarization, wave length, or any other observable characteristic of the beam.
Polarization separation of the modes takes advantage of the fact that the two modes of a two-mode non-polarized laser are polarized in orthogonal directions. Theoretically, the directions of the two polarizations are set randomly with switching on of the laser. In practice, however, because of inevitable anisotropy of the resonating cavity, no matter how small, these directions are always the same for a given tube and can be measured once and for all, and thus provide the basis for mode separation. For example, a polarizing beamsplitter inserted in the path of the laser beam can be oriented in such a way (or, equivalently, given the orientation of the polarizing beamsplitter, the laser can be rotated around its axis) that the polarization directions of the beamsplitter are parallel to those of the laser modes and, thus, each of the beams contains a different mode.
In wave length separation one can make use of the fact that the wave length spacing of the modes in a laser is Δλ=λ 2 /(2L), where λ is the mean wave length and L is the length of the laser tube. This can be utilized, in principle, by means of any instrument used in high-resolution spectroscopy, such as a diffraction grating, where each wave length is deflected by a different angle and, say, split apertures are used to select the mode in the center (FIG. 1a) and the off-center modes (FIG. 1b). It is equally possibly to use Fabry-Perot etalons with appropriate finesse, tuned so as to transmit the central wavelength (FIG. 1a) and the off-center wavelengths (FIG. 1b).
In principle, mode separation can also be based on any other observable characteristic of the beam. For instance, it is possible to modulate the modes emitted from the laser in polarization, intensity, or amplitude, and separate the modes at detection by appropriate electronic demodulation.
Because of the frequency (and wave length) difference between the modes, there is a change in the number of wave lengths per optical path difference and, hence, there is a "phase shift" between the fringe systems of the two modes, which, if uncorrected, would result in a discontinuous change in counting at the switching moment. For instance, in the problematic half-tube-length point this phase shift is 180° and there is 1/2 pulse gained (or lost) at the switching moment. With fluctuations of the laser tube length the count will be switched back and forth between the two modes and this discontinuity error can conceivably accumulate. However, since at the moment of count switching the intensities of the two modes are almost equal and both detection systems, (211) and (212) are able to produce counts, this relative "phase shift" between the modes at the switching moment can be determined easily and a count correcting difference can be added to the total number of pulses in the main counter (214), thus eliminating the above discontinuity. In fact, the count discontinuity is equal to the fractional part of D/(2L), where L is the tube length and D is the optical path difference between the two interferometer beams.
Referring, for illustration to FIG. 1, in the case of FIG. 1a the S mode lies close to the center of the Doppler emission profile, is much stronger than the other mode, and is, therefore, chosen for counting. With temperature fluctuations, the modes drift (say, to the left) and may become comparable in intensity (FIG. 1b). With further drift, the P mode will become stronger than the S mode and the count will be switched to that mode. If the drift continues in the same direction, eventually the original S mode will travel outside the limits of the Doppler curve (and will go to extinction) and another S mode will enter the confines of the Doppler curve from the right, etc.
The accuracy of the count switching interferometer is limited by the maximum variation of the wave length of the mode used for counting, i.e., by the maximum deviation of the wave length of a mode from the wave length corresponding to the center of the emission line. Clearly, this deviation cannot exceed half the spacing between the modes, so that the relative accuracy is better than λ/(4L), i.e., 10 -6 . This is already a significant improvement over a conventional interferometer with a non-stabilized laser where the variation of the wave length of a mode is limited by the Doppler curve itself. However, since in the situation (FIG. 1b) where the mode deviation is the largest both modes are present and able to produce counts, it is possible to average the counts in the S and P modes in order to reduce the wave length uncertainty even further.
The method of count switching can also be applied to three-mode lasers and to multimode lasers in general, either on the basis of wavelength decoding or polarization decoding. In the latter case one makes use of the fact that the polarizations of the neighboring modes are orthogonal. The only difference here from the two-mode case is that the fringe picture obtained for a given polarization will contain the signals of all the modes characterized by that polarization. However, since the spacing between the modes having the same polarization in a non-polarized laser is relatively large (twice the mode spacing), the resulting fringe picture in a given polarization will be observed as the fringe picture of the strongest mode with a small loss of contrast caused by the presence of the other modes. For instance, in the case of a three-mode laser, if one of the modes is close to the center of the Doppler curve (the S 1 mode in FIG. 1c), its fringe picture will be contaminated by that of the S 2 mode. However, the intensity of the S 2 mode is considerably smaller than that of the S 1 mode so that its effect on the fringe contrast will be minimal. In the case where the intensities of two S modes are comparable (FIG. 1d), it is the P mode that will be the strongest and used for counting. The maximum number of modes that can be accomodated by the method of count switching with the polarization technique depends on the exact shape of the emission profile and can exceed four. Note that because of a smaller mode spacing there is a corresponding gain in accuracy compared with shorter tubes.
The method of count switching is not limited to the Twyman-Green optical scheme and can be applied to any two-beam interferometer with a non-stabilized laser where it is desirable to extend the optical path difference in the two beams.
EXAMPLES
A preferred embodiment of the present invention is illustrated in FIGS. 3 and 4, implementing the method of count switching with polarization separation of the modes for a Twyman-Green interferometer for measurement of displacement. The optical scheme is illustrated in FIG. 3 where: (301) is a short-tube gas laser such as one having the 7647 HeNe tube by Siemens; (302) is a "main" beamsplitter separating the main laser beam into a refernce beam and a measuring beam; (303) is a retroreflector for the reference beam, which is fixed relative to the main beamsplitter (302); (304) is a remote retroreflector in the measuring path, whose movement defines the displacement to be measured [the beamsplitter (302) is taken to be not polarizing and, therefore, the reference beam and the measuring beam each contain both polarizations]; (305) and (306) are polarizing beamsplitters in the paths of the two recombined beams emerging from the main beamsplitter (302), each carrying a combined interference fringe picture; (307)-(310) are photodetectors (such as PIN photodiodes) for registration of the intensity of fringe signals; (311) is an additional polarizing beamsplitter inserted in the path of the beam emitted from the back mirror of the laser (rather than splitting off a part of the main beam); and (312) and (313) are two additional photodetectors. The main beamsplitter (302) is advantageously arranged to have absorption so that the interference fringe pictures in the two recombined beams [which enter the polarizing beamsplitters (305) and (306)] are shifted in phase with respect to each other. The phase shift depends on the amount of absorption and is ideally 90° so that the corresponding signals can be used in quadrature for bidirectional electronic fringe counting.
The polarizing beamsplitters (305), (306), and (311) are oriented so as to separate the two polarizations of the two laser modes, to be called S and P, and there is a photodetector for each polarization in each separated beam. For concreteness, let us assume that the photodetectors (307), (310), and (313) receive the P-polarized component of the beams and that the photodetectors (308), (309), and (312) receive the S-polarized component of the beams. As a result, there are two fringe-counting electro-optical arrangements: the photodetectors (307) and (310) for bidirectional counting in the P-polarized mode, each receiving the P-polarized component of the two recombined beams whose fringe pictures are, as before, shifted in phase by 90° with respect to one another (signals in quadrature), and the photodetectors (308) and (309) for bidirectional counting in the S mode. The photodetectors (312) and (313), which are inserted in the path of the beam emitted from the back mirror of the laser, measure the intensities of the P and S modes, and their signals are used for controlling the switching of counting to a stronger mode whenever necessary. (It is also possible to control the switching on the basis of the maximum contrast of the fringe signals.) The displacement measured is obtained as a number of pulses multiplied by λ/2.
A block diagram of an embodiment of the count switching electronics is shown in FIG. 4. There, (401), (402) and (403), (404) are the two signal pairs from the S and P photodetector pairs (308), (309) and (307), (310), with the interference signals in each pair shifted by ˜90° relative to each other (in quadrature) as explained above; (411) and (412) are bidirectional counters for the P and S modes; (405) and (406) are the mode intensity signals, which are generated by the photodetectors (312) and (313) and which are fed into the intensity comparator (410); (413) is the mode selector which passes the counts of the stronger mode to the main counter (415) and which generates a mode switching trigger signal to the count corrector (414); finally, the count corrector (414) calculates the count correcting difference and adds it, upon receiving the trigger signal from the mode selector (413), to the total number of pulses in the main counter (415). In order to prevent possible rapid "hopping" of the selector (413) from one mode to another in the case where the intensities of the two modes are approximately equal (as in FIG. 1b), a simple hysteresis rule is imposed in the mode selector (413), effecting the mode switch only after the intensity difference exceeds a certain threshold.
With a slight modification of the electronics, the same arrangement can implement count averaging in order to increase the accuracy in the case of FIG. 1b. Namely, whenever both intensity signals (405) and (406) exceed the required threshold, the counts of the P and S counters (411) and (412) are averaged before passing them to the main counter (415). In this case the mode selector (413) and count corrector (414) deal with three possible situations: S mode alone, P mode alone, and S and P mode averaged, and with two possible count switchings: S←SP and SP→P.
A possible use of the distance measuring interferometer is shown schematically in FIG. 5 which illustrates the use of a count switching interferometer as a displacement resolver for controlling a linear translation stage. There, (51) is a remote retroreflector mounted on the carriage (52) of the translation stage; (55) is the laser; (53) is the rest of the interferometer mounted on the immobile part of the translation stage; and (54) is a motion actuator servo-controlled on the basis of the signal generated by the interferometer (53).
We have built a prototype device shown in FIG. 5 implementing the optical scheme in FIG. 3 and having the count switching electronics as in FIG. 4. The device was based on the 7647 laser tube by Siemens and has a measuring range of 800 mm. The measuring accuracy is, as tested versus a 5ZL150 interferometer by Spindler and Hoyer, 1μ per meter. But constrast, if the same device is operated as a conventional interferometer without count switching, then the measuring accuracy falls to ˜2.5μ per meter, and the measuring range is reduced more than 10 times. Viz., when the measuring range approaches ˜75 mm, the fringe constrast disappears (and reappears) periodically, as indeed should be expected from theoretical considerations. | The present invention relates to a method for greatly extending the effective coherence length of non-stabilized lasers allowing one to use them in interferometers with large optical path differences. The embodiment described as an example comprises a robust Twyman-Green interferometer for accurate measurement of extended displacements. | 6 |
This application is a continuation of application Ser. No. 08/170,031, filed Dec. 20, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to television cameras, and more particularly to black shading correction for television cameras.
2. Background of the Invention
Television cameras are in widespread use in a variety of sensing, communication, and scientific applications. With the advent of improvements such as high-definition systems, camera defects will become more apparent to the television viewer. Thus, camera improvements are desirable. One of the defects to which cameras are subject is "dark current" or "black shading", which is current or charge (signal) which arises from the characteristics of the camera imager (the actual photosensitive screen) itself, and which does not depend on the image falling thereon.
The dark signal may be viewed as being the imager signal when a cap is placed on the associated lens to eliminate light from the image. In the context of charge-coupled device (CCD) imagers, the dark current may be viewed as "leakage" which results in charge which accumulates in each picture element (pixel) of the "A" register of the imager during the image integrating interval. Thus, each pixel includes a charge portion attributable to the integration of image information during the integrating interval, and also includes a charge portion attributable to dark current over the same interval.
In general, the pixels of a CCD imager are similar to the other pixels, except in the case of point defects, so the dark signal contribution in each pixel tends to be the same as in the other pixels. Thus, it might be thought that subtraction of a single value of charge from each pixel might be sufficient to correct for the presence of dark current. However, charge is read from the pixels of the A register of a CCD imager by moving columns of pixel information simultaneously along the A register into a "B" register, where the information is stored for further processing. During the transfer of charge from the A register to the B register, dark current continues to accumulate in the pixels, with the result that those pixels which dwell in the A register for the longest period of time tend to accumulate more charge from the dark current than those which dwell for a lesser time. Thus, the "upper" pixels, which must traverse the entire A register during the charge transfer "pull-down" period before arriving at the B storage register, accumulate more charge from the dark current than those at the bottom of the A register, which arrive at the B register earlier.
This effect causes a "shading" across the imager, which in principle requires a ramp-like correction signal to be subtracted from the imager signal, with the ramp waveform applied in each column of read-out image information, from bottom to top of the image, for correction thereof. A parabolic correction waveform is sometimes necessary. A further correction waveform may be necessary along each row, in which case the correction waveforms are summed to produce the total correction waveform to be subtracted from the imager signal.
In the case of vacuum-type imaging tubes, the photosensitive screen is subject to dark signal variations attributable to such conditions as slight thickness variations of the photosensitive material across the screen, variations in its conductivity, or in the interface between the material and the underlying substrate. Thus, the dark signal correction required in a tube-type imager may be more complex than that required in a CCD imager.
SUMMARY OF THE INVENTION
A camera generates an approximation of the dark current or black shading, and subtracts the approximation signal from the signal generated by the camera during normal image-sensing operation. In a particular embodiment of the invention, counters generate location signals representative of the pixel currently being read, and the location signals are processed by functions such as multiplication and/or squaring, and by weighting, to produce components of the approximation of the dark signal. The components are subtracted from the imager signal, to reduce the dark shading. In one embodiment of the invention, the functions are automatically selected from among a plurality of preselected functions, and implemented by look-up tables.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified block diagram of a camera according to the invention;
FIGS. 2a and 2b are plots of the dark signal of an imager in the horizontal and vertical directions, respectively;
FIG. 3 is a simplified block diagram of a correction signal generator which may be used in the arrangement of FIG. 1;
FIGS. 4a and 4b are plots of the dark signal corresponding to those of FIGS. 2a and 2b, corrected by the arrangement of the invention with a first correction function; and
FIG. 5 is a simplified block diagram of an alternative correction signal generator which may be used in the arrangement of FIG. 1 instead of the arrangement of FIG. 3;
FIGS. 6a and 6b are plots of the dark signal corresponding to those of FIGS. 2a and 2b, corrected by the arrangement of the invention with a second correction function.
FIG. 7 is a simplified block diagram of a further alternative correction signal generator which may be used in the arrangement of FIG. 1 instead of the arrangement of FIG. 3.
DESCRIPTION OF THE INVENTION
FIG. 1 is a simplified block diagram of a monochromatic camera 10, which may also be considered to be one imager of a multiimager color camera. In FIG. 1, a lens 12 focuses an image represented by an arrow 14 onto the surface of an imager 16, which is associated with horizontal x and vertical y axes. The imager 16 may be either a vacuum tube-type device such as a saticon or plumbicon imaging device or it may be a semiconductor device using charge coupled devices (CCD's) or bucket brigade devices. An image readout arrangement illustrated as a cylindrical object 18 is associated with the imager 16, for reading charge or current from the imager, under the influence of a scan control generator 20 and its coupling 22a, 22b to image readout arrangement 18, and for producing signal representative of the image (and its associated dark signal) on an output signal path 24.
Those skilled in the art know that, as scan generator 20 of FIG. 1 operates, readout device 18 reads across screen 16 in rows parallel to the x axis, with each successive row closer to the bottom (or top) of screen 16, until the entire screen (or at least the active portion thereof) has been read. Scan generator 20 may operate continuously, reading signal from one part of the photosensitive screen while light is integrated on the remainder of the screen.
The signals produced from the screen by readout device 18 of FIG. 1 are applied to a preamplifier 26 for low-noise amplification, and are applied from the output of amplifier 26 to the noninverting (+) input port of a summing circuit 28. A shading correction generator 30 is coupled by a path 33 to scan generator 20 for receiving information relating to the row and column of the pixel currently being read, and for generating a shading correction signal, as described below.
The output signal produced by the preamplifier 26 may also be applied to an optional accumulator 27 (shown in phantom). As described below, the accumulator 27 provides a measure of the effectiveness of a given correction function. When the accumulator 27 is used, the system can automatically select the correction function that will be used from among a group of possible functions. Without the accumulator 27 or some other apparatus for developing an objective measure of quality, function selection would be guided by a human operator.
The shading correction signal relating to the pixel currently being read from screen 16 of FIG. 1 is applied over a signal path 31 to the inverting (-) input port of summing circuit 28, for subtraction of the correction signal from the signal representing the current pixel, to thereby produce a video signal corrected for dark signal.
The corrected video signal produced by camera arrangement 10 of FIG. 1 is made available for other processing, which may include, for example, correction for geometric distortions of various sorts, color balance correction and aperture correction. The camera output signals include the corrected video signal, and a synchronization signal (sync) from scan generator 20, which may be combined with the video signal at later processing stages.
FIG. 1 also illustrates a lens cap 40, which may be placed over lens 12 to prevent light from entering the lens and falling onto photosensitive screen 16. With the lens cap in place on lens 16, any signal produced on output signal path 24 must be dark signal.
It is difficult to represent the shading across a two-dimensional screen as a two-dimensional drawing. A two-dimensional FIGURE, however, can easily represent the variation of shading in one dimension. FIG. 2a illustrates the uncorrected dark signal from the 200 th row of a representative imager, and FIG. 2b is a plot of the uncorrected dark signal from the 200 th column. To aid in clearly seeing the signal, a constant offset value of thirty-two intensity units has been added to the actual signal intensity in FIGS. 2a and 2b, and also in FIGS. 4a, 4b, 6a and 6b. In FIGS. 2a and 2b, it can be seen that the two-dimensional dark signal function is complex, and not amenable to correction by a simple waveform such as a ramp or a parabola.
As illustrated in FIG. 1, the uncorrected signal is applied to shading correction signal generator 30 by a signal path 32. FIG. 3 is a simplified block diagram of one embodiment of shading correction generator 30. In FIG. 3, elements corresponding to those of FIG. 1 are designated by like reference numerals. In FIG. 3, a row counter 310 receives, from scan generator 20 of FIG. 1 by way of signal path 33, information relating to the row number currently being read. The information may simply be a pulse occurring at a defined point along the scan, such as at the beginning or end of a row, and row counter 310 may be simply an accumulator, in which the current count represents the current row. Similarly, a column counter 312 receives information relating to the scanning, and counts each pixel along a row. In the ordinary scanning arrangement, column counter 312 counts at a much higher rate than row counter 310. Thus, in the usual arrangement, column counter 312 may count five hundred or more pixels in the first row of "image" information read from the screen, and then is reset to zero by the end-of-row pulse, to count a like number for the second row of image information, continuing in a like manner to count in a horizontal (H) direction until all rows have been accounted for. Similarly, the row counter counts in the vertical (V) direction, and may be reset to zero count at the end of a field or frame, as appropriate.
The counts produced by row counter 310 and column counter 312 of FIG. 3 together constitute two variable signals which are inputs to the remainder of the correction signal arrangement of FIG. 3. A third input is a constant-value input from direct current (DC) source or generator 314, for reasons described below. Weighting input signals w 0 , w 1 , w 2 , w 3 , w 4 are also received over a weighting data bus 309. The DC signal from generator 314 is applied to an input port of a first multiplier 321. The row count is applied to an input port of a second multiplier 322 and to both input ports of a further multiplier 331. The column count from counter 312 is applied to the input port of a multiplier 324 and to both input ports of a further multiplier 332. Further multiplier 331 receives the row count at both its input ports, and multiplies the row count by itself to generate a row squared count equal to the square of the row count. The row count squared signal is applied from multiplier 331 to an input port of a multiplier 323. Similarly, further multiplier 332 receives the column count at both its input ports to generate a column count squared signal equal to the square of the column count. The column count squared signal is applied from multiplier 332 to an input port of a multiplier 325.
As also illustrated in FIG. 3, a weight signal (weight) w 0 is applied from a processor 308 by way of a weighting data bus 309, and by way of a single-pole, double throw switch 341 (in the illustrated switch position) to a further input port of multiplier 321, and weights w 1 , w 2 , w 3 , and w 4 are applied, by way of bus 309 and switches 342, 343, 344 and 345, respectively, to further input ports of multipliers 322, 323, 324, and 325, respectively.
The multiplied or product output signal of each multiplier 321, 322, 323, 324, and 325 is applied to the input port of a corresponding accumulator (A) 351, 352, 353, 354, and 355, respectively, and the accumulated signals are applied over a data path 357 to control processor 308, to aid in generating the weights. The product signals at the outputs of multipliers 321, 322, 323, 324, and 325 are summed together by a network 360 of summing circuits, including summing circuits 361, 362, 363, and 364, to produce the desired shading correction signal on signal path 31. More particularly, the output product signals from multipliers 321 and 322 are applied to a summing circuit 361, and the output product signal from multipliers 323 and 324 are summed together in a summing circuit 362. The summed signals from summing circuits 361 and 362 are applied to a summing circuit 363, the summed output of which is applied to a further summing circuit 364, in which they are added to the output signal from multiplier 325.
The arrangement of FIG. 3 also includes uncorrected signal path 32, which carries uncorrected signals from preamplifier 26 of FIG. 1 to the second throws of switches 331-335 (where the hyphen represents the word "through"). In the illustrated positions of switches 341-345, the uncorrected signal is not used in the arrangement of FIG. 3.
In normal operation of the camera of FIG. 1 with the correction waveform generator 30 as illustrated in FIG. 3, a constant component of the shading correction signal is generated by multiplication, in multiplier 321, of DC from generator 314 by the value of weight w 0 . This constant value is determined, in a manner described below, to compensate for the constant component of the dark signal. This component corresponds, for example, with an intensity value of about 32 in FIG. 2a, if the offset value appearing therein were due to the imager rather than to an intentional offset. Also during normal operation, a ramp-like compensation signal component in the vertical or y direction is generated in multiplier 323 by the multiplication of the row count by weight w 2 .
Similarly, a ramp-like compensation signal component in the horizontal or x direction is generated in multiplier 324 by multiplying the column count by weight w 3 . Parabolic correction waveforms in the y and x directions are generated in multipliers 323 and 325, respectively, by multiplying the row squared and column squared signals produced by multipliers 331 and 332, respectively, by weights w 3 and w 5 , respectively. Thus, a constant correction signal component, and vertical-and horizontal-direction ramp and parabolic correction signal components, are generated at the outputs of multipliers 321-325, with amplitudes which are independently controllable by the magnitudes of the weights. The components are summed together by summing arrangement 360, and applied over path 31 to the inverting input port of summing circuit 28 of FIG. 1, to be subtracted from the uncorrected signal to thereby produce the corrected signal.
A correction signal which compensates for the particular dark current function of the imager 16 may be generated automatically as disclosed below.
The correction signal is estimated by a least-squares procedure. In the general theory of least-squares estimation, let d(x) be a function to be modeled by f(x), where f(x) is defined by equation (1). ##EQU1##
where: x is an input vector; and
w 0 , w 1 , . . . w N-1 are weights which cause f(x) to model d(x);
Least-squares estimation finds the set of w i (or the vector w) that satisfies equation (2). ##EQU2##
The extreme values, or extrema, of a multidimensional function are found when the partial derivatives of the function are zero, satisfying equation (3). ##EQU3##
Combining equations (1) and (3), we obtain equation (4). ##EQU4##
Which leads to the matrix equation (5). ##EQU5##
where N1=N-1. Using matrix notation, equation (5) becomes equation (6).
d=F.sup.· w (6)
Since we are only interested in w, it is only necessary to find the inverse of F, whereupon the weighting factors w may be determined as shown in equation (7).
w=F.sup.-1 d (7)
In order to apply the above theory to correction of dark signal, d(x) is the dark signal to be modeled, where the vector x is given by equation (8).
x=[h.sub.pos, v.sub.pos, frame] (8)
In this instance, the correction signal, that is to say the signal that is combined with the image to compensate for the signal d(x), is the signal -f(x). To find the weighting factors, w, of the correction image, we must find F -1 and d and compute their product. Note that F -1 is independent of d(x), but is dependent on the function f(x) chosen for the model. Thus, F -1 can be calculated "off-line" based on the selected modeling function f(x). Only the d vector, namely d(x)f i (x), must be computed "on-line". In summary, the procedure for calculating the weights includes the steps of:
(a) select the modeling functions f i (x);
(b) compute F -1 off-line using equations (5) & (6);
(c) measure the d vector on-line, by d(x)f i (x);
(d) using equation (7), compute the weights.
The weights are established in the arrangement of FIGS. 1 and 3 by throwing switches 341-345 to their alternate positions (i.e. passing the uncorrected signal), and capping the lens. The uncorrected dark signal is then applied to one port of each of multipliers 321-325 instead of the weights w 0 -w 4 . This has the effect of multiplying the dark signal by the constant, ramp or parabolic inputs, which are based on the position of the pixel in the image.
For example, the constant DC input from generator 314 is multiplied in multiplier 321 by the dark signal at each pixel, and the product for each pixel is applied to accumulator 351. Accumulator 351 accumulates the product signal from multiplier 321 over an entire field, frame or a plurality of frames. The resulting accumulation is a representation of the constant component of the dark signal, as modified by the constant value from DC generator 314. Similarly, multipliers 322 and 324 multiply the dark signal by vertical- and horizontal-direction ramps, respectively, and accumulators 352 and 354 accumulate their respective product signals for all pixels of the field or the selected number of frames.
Multipliers 323 and 325 of FIG. 3 multiply the dark signal by vertical- and horizontal-direction parabolic signals, respectively, and accumulators 353 and 355 accumulate the resulting product signals, corresponding to d(x)f i (x). The accumulated signals are read from accumulators 351-355 by way of data paths of bus 357 to processor 308, which performs the calculation of weights w 0 -w 4 from the accumulated signals, using equation (7) in accordance with the above description. Thereafter, the lens cap is removed, switches 341-345 are thrown to their illustrated positions to apply the weights to multipliers 321-325, and normal operation may proceed.
FIG. 4a is a plot of the 200 th row of a dark signal image of the imager which made the plots of FIGS. 2a and 2b, corrected by the above described apparatus, corrected by the correction function f(h,v) given in equation (9).
f(h,v)=w.sub.0 +w.sub.1 h+w.sub.2 h.sup.2 +w.sub.3 v+w.sub.4 v.sup.2 (9)
FIG. 4b is a corresponding plot of the 200 th column, corrected by the same function f(h,v) as for correction of the column. Comparison of the plots of FIGS. 4a and 4b with the uncorrected plots of FIGS. 2a and 2b, respectively, shows that there is a correction, but that the correction is incomplete, thereby suggesting that the selected correction function, f, might advantageously include additional or different terms.
FIG. 5 is a simplified block diagram of a portion of a correction signal generator according to the invention, which implements a function f(h,v) given by equation (10).
f(h,v)=w.sub.0 +w.sub.1 h+w.sub.2 e.sup.-10v +w.sub.3 v+w.sub.4 v.sup.2 (10)
different from the function produced by correction signal generator of FIG. 3. Elements of FIG. 5 corresponding to those of FIG. 3 are designated by like reference numerals. In FIG. 5, the constant value signal from DC generator 314 is applied to multiplier 321 for multiplication by weight w 0 , the row signal from row counter 310 is applied to multiplier 322 for multiplication by weight w 2 , the row signal is applied to both input ports of a multiplier 331 for squaring, and the column signal from column counter 312 is applied to multiplier 324 for multiplication by weight w 3 , just as in the arrangement of FIG. 3. Unlike the arrangement of FIG. 3, the row signal from row counter 310 of FIG. 5 is applied to a memory arrangement 532, arranged as a random-access look-up table (LUT), which is preprogrammed with values implementing the e -10v component of equation 10. LUT 532 may be a preprogrammed read-only memory (ROM), but is preferably a nonvolatile reprogrammable random-access memory (RAM). The v 2 component from multiplier 531 is applied to multiplier 323 for multiplication by weight w 2 , and the e -10v component from LUT 532 is applied to multiplier 325, for multiplication by weight w 4 .
FIGS. 6a and 6b are plots of the 200 th row and column of the corrected dark signal, respectively, where the correction function, f(h,v), is given by equation (10)
As illustrated, the correction is improved over that of FIGS. 4a and 4b.
FIG. 7 is a simplified block diagram of a portion of a correction signal generator according to the invention, which is capable of generating the same functions as those of the arrangements of FIGS. 3 and 5, and other functions. Elements of FIG. 7 corresponding to those of FIG. 3 are designated by like reference numerals. In FIG. 7, the row and column count signals from row counter 310 and column counter 312 are applied as input addresses to each of LUTs 731, 732, 733, 734 and 734 LAST . Each LUT is preprogrammed with information relating the count to a particular function, as described above in relation to LUT 532. The resulting count-related functions are applied from LUTs 731-734 LAST to corresponding ones of multipliers 322-325 LAST . LUT memories 731-734 LAST need not be full frame memories, but may have a limited depth in that bits of lesser significance are not recorded, whereby that the amplitude quantization is coarse relative to the quantization (number of bits) representing the signal, and/or may have the addresses similarly limited to bits of greater significance, which results in treating "blocks" of two, four, eight . . . N mutually adjacent pixels in the same manner. Thus, memory LUTs 731-734 LAST may be relatively small, if desired. Naturally, the memories of LUTs 731-734 LAST may be different portions or pages of a common memory structure.
During dark current compensation setup, controller or processor 308 of the arrangement of FIG. 7 may sequentially select each of several preselected functions, such as the functions of equations 9 and 10, previously stored in nonvolatile memory. The setup process may include the sequential steps of (a) set the weights to zero, (b) run one field or frame and read the accumulator outputs, (c) load the first selected function into LUT, (d) for the first selected function, determine and record the weights using the accumulator outputs, (e) set the weights according to the determination, (f) read a dark image from the imager 16, and (g) read and record the value held in the optional accumulator 27 after the dark image has been read. Steps (a) through (g) are repeated for each of the second, third . . . last of the stored functions. When all the stored functions have been processed, those functions (and their corresponding weights) are selected for use which resulted in the lowest value from accumulator 27.
The arrangement of the invention provides automatic dark signal correction without the large memory requirements of the prior art, and which can adapt to changes in the dark current caused by aging and other factors.
Other embodiments of the invention will be apparent to those skilled in the art. For example, shading correction summer 28 of FIG. 1 may precede preamplifier 26, if desired, rather than following it. | A video camera generates an approximation of the dark current or black shading distortion signals based on scan position in the image, and subtracts the approximation signal from the signal generated by the camera during normal image-sensing operation to reduce the black shading distortion. In a particular embodiment of the invention, counters generate location signals representative of the location of pixel currently being read, and the location signals are processed by functions such as squaring or raising to a constant power, and by weighting, to produce components of the approximation of the dark signal. The components are subtracted from the imager signal, to reduce the dark shading. In one embodiment of the invention, the functions are automatically selected from among a plurality of preselected functions, and implemented by look-up tables. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a division of application Ser. No. 163,422, filed June 27, 1980, abandoned, which is a division of application Ser. No. 839,905, filed Oct. 6, 1977, now U.S. Pat. No. 4,234,701.
The present invention relates to thermoplastic molding compositions which are based on an intimate admixture of a copolymer of vinyl aromatic compound and an α,β-unsaturated cyclic anhydride and a grafted, copolymerized or blended impact modifier, with or without a polyphenylene ether resin and optionally a liquid polybutadiene present. The compositions of this invention provide molded articles having good overall mechanical properties, e.g., impact strength, tensile strength, tensile elongation, and the like.
BACKGROUND OF THE INVENTION
Vinyl aromatic resins, e.g., polystyrene, have been found to be useful in thermoplastic molding compositions. Vinyl aromatic resins have poor heat distortion and impact resists ce, however, and attempts have been made to upgrade these properties. One approach has been to modify the vinyl aromatic resins by copolymerizing these materials with α,β-unsaturated cyclic anhydrides, to form copolymers such as poly(styrene-maleic anhydride). Although improvements in heat resistance and solvent resistance are provided, the resulting copolymers are somewhat brittle, and they do not have good resistance to impact.
Various attempts have been made to improve the impact resistance of copolymers of vinyl aromatic resins and α,β-unsaturated cyclic anhydrides. For instance, these copolymers have been blended with nitrile rubbers. Blends of nitrile rubber and styrene-maleic anhydride copolymers are disclosed in U.S. Pat. Nos. 2,914,505 and U.S. 3,641,212. With some of these compositions, however, the components are not compatible, and the compositions are difficult to prepare.
The following commonly assigned copending applications disclose proposals to solve the problems stated above. Lee and Abolins, Ser. No. 477,435, filed June 7, 1974 now U.S. Pat. No. 4,124,654, who employ block copolymers or graft copolymers in combination with the vinyl aromatic/unsaturated cyclic anhydride copolymers; Lee, Ser. No. 671,569, filed Mar. 29, 1976, who discloses block copolymers with rubber-modified vinyl aromatic/unsaturated cyclic anhydride copolymers; Abolins and Lee, Ser. No. 671,341, who disclose polyphenylene ether resins with vinyl aromatic/unsaturated cyclic anhydride copolymers; and Haaf and Lee, Ser. No. 693,895, filed June 8, 1976, who disclose radial teleblock copolymers in combination with vinyl aromatic/unsaturated cyclic anhydride copolymers, optionally rubber modified. The applications are incorporated herein by reference.
It has now been surprisingly discovered that copolymers of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride can be combined with an all acrylic emulsion graft copolymer to form compositions which can be molded to articles having excellent mechanical properties, including good impact strength, tensile yield and elongation, especially when combined with a polyphenylene ether resin. It has further been discovered that such an all acrylic emulsion graft copolymer can be used to enhance the important properties of rubber modified vinyl aromatic/unsaturated cyclic anhydride copolymers), with and without the addition of a polyphenylene ether resin.
It has been further discovered that the toughness of both unmodified and rubber-modified vinyl aromatic/unsaturated cyclic anhydride copolymers can be remarkably enhanced by combination with a vinyl aromatic, acrylonitrile-diene graft copolymer. The results are surprising in view or earlier work with an acrylic-vinyl aromatic-diene rubber graft copolymer.
Still a further discovery has been made in which compositions comprising a vinyl aromatic/unsaturated cyclic anhydride copolymer, a polyphenylene ether resin, and a graft copolymer resin, a rubber modified vinyl aromatic resin, or a segmented copolyester resin are vastly improved in ductile impact properties by adding a small amount normally liquid diene oligomer.
A further broad discovery resides in finding that lower than expected levels of polyphenylene ether resin can be employed in combination with vinyl aromatic/unsaturated cyclic anhydride copolymers, than would have been expected from work with vinyl aromatic homopolymers and graft copolymers, thus permitting retention of heat distortion temperatures at higher predetermined levels.
SUMMARY OF THE INVENTION
The present invention provides, in its broadest aspects, a thermoplastic composition which comprises an intimate admixture of:
(a) a copolymer of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride, and
(b) an impact modifier comprising (i) a graft copolymer comprising a vinyl aromatic compound, and a diene, alone, or in combination with an acrylonitrile; or (ii) a graft copolymer consisting essentially of acrylic ester units.
In a preferred feature, such compositions will also include a polyphenylene ether resin.
In another aspect, this invention provides a thermoplastic molding composition comprising an intimate admixture of
(a) a diene rubber modified copolymer of styrene and maleic anhydride;
(b) an impact modifier comprising
(i) a graft copolymer comprising a vinyl aromatic compound, and a diene alone or in combination with an acrylonitrile;
(ii) a graft copolymer comprising an acrylic ester, alone, or in combination with a vinyl aromatic compound, alone, or in further combination with a diene;
(iii) a rubber modified vinyl aromatic compound comprising from 20 to 45 percent by weight of a diene rubber; or
(iv) a segmented polyester having a multiplicity of recurring intralinear etherester and/or ester units;
(c) a polyphenylene ether resin; and
(d) an effective ductile impact strength improving amount of low molecular weight normally liquid polybutadiene oligomer.
In still another aspect, the present invention provides a process for the preparation of a thermoplastic composition which comprises intimately admixing
(a) a copolymer of a vinyl aromatic compound and an α,β-unsaturated anhydride, and
(b) a polyphenylene ether resin, (a) being added in an amount which is at least sufficient to improve the processability of the combination of (a) and (b) without decreasing the heat distortion temperature of (a) and (b) substantially in comparison with a composition of (b) with a polymerized vinyl aromatic compound essentially free of any copolymerized α,β-unsaturated anhydride, at the same vinyl aromatic compound control.
DETAILED DESCRIPTION OF THE INVENTION
The copolymers of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride (i) are well known in the art and are described in the literature. In general, they are prepared by conventional bulk solution or emulsion techniques using free-radial initiation. For example, styrene-maleic anhydride copolymers can be obtained by simply reacting the two monomers, i.e., styrene and maleic anhydride, at 50° C. in the presence of benzoyl peroxide. The rate of polymerization may be better controlled if a solvent such as acetone, toluene or xylene is used.
The vinyl aromatic compound of component (a) can be derived from compounds of the formula: ##STR1## wherein R 1 and R 2 are selected from the group consisting of (lower) alkyl or alkenyl groups of from 1 to 6 carbon atoms and hydrogen; R 3 and R 4 are selected from the group consisting of chloro, bromo, hydrogen and (lower) alkyl of from 1 to 6 carbon carbon atoms; R 5 and R 6 are selected from the group consisting of hydrogen and (lower) alkyl and alkenyl groups of from 1 to 6 carbon atoms or R 5 and R 6 may be concatenated together with hydrocarbyl groups to form a naphthyl group. These compounds are free of any substituent that has a tertiary carbon atom. Styrene is the preferred vinyl aromatic compound.
The α,β-unsaturated cyclic anhydride of component (i) can be represented by the formula: ##STR2## wherein the dotted lines represent a single or a double carbon to carbon bond, R 7 and R 8 taken together represents a ##STR3## linkage, R 9 is selected from the group consisting of hydrogen, vinyl, alkyl, alkenyl, alkylcarboxylic or alkenyl-carboxylic of from 1 to 12 carbon atoms, n is 1 or 2, depending on the position of the carbon-carbon double bond, and m is an integer of from 0 to about 10. Examples include maleic anhydride, citraconic anhydride, itaconic anhydride, aconitic anhydride, and the like.
The preparation of these copolymers is described in U.S. Pat. No. 2,971,939; U.S. Pat. No. 3,336,267 and U.S. Pat. No. 2,769,804, the disclosures of which are incorporated herein by reference.
The copolymers which comprise component (a) include rubber-modified copolymers thereof. The rubber employed in preparing the rubber-modified copolymers of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride can be a polybutadiene rubber, butyl rubber, styrene-butadiene rubber, acrylonitrile rubber, ethylene-propylene copolymers, natural rubber, EPDM rubbers and the like.
The preparation of rubber-modified copolymers of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride is described in Netherlands No. 72,12714, which is incorporated herein by reference.
Component (a) can comprise from 40 to 1 parts by weight of the α,β-unsaturated cyclic anhydride, from 60 to 99 parts by weight of a vinyl aromatic compound and from 0 to 25 parts by weight of rubber. The preferred polymers will contain about 25-5 parts by weight of the α,β-unsaturated cyclic anhydride, 75-95 parts by weight of the vinyl aromatic compound, and 10 parts by weight of rubber.
A preferred unmodified vinyl aromatic α,β-unsaturated cyclic anhydride copolymer useful in the composition of this invention is Dylark 232, commercially available from Arco Polymers. Dylark 232 is a styrene-maleic anhydride copolymer containing about 11% maleic anhydride, the balance being styrene. A preferred rubber-modified vinyl aromatic α,β-unsaturated cyclic anhydride copolymer is Dylark 240, which is also available from Arco Polymers. Dylark 240 is a high impact styrene-maleic anhydride copolymer containing 9-10% rubber and 9% maleic anhydride, the balance being styrene.
The graft copolymers (b) (i) and (ii) are available commercially or can be prepared by following the teachings of the prior art. As an illustration, the graft polymerization product of an acrylic monomer, a vinyl aromatic monomer and/or acrylonitrile monomer and a diene rubber preferably comprises a backbone polymer of the units of butadiene or butadiene and styrene, wherein the butadiene units are present in quantities of at least 40% by weight of the backbone polymer, (a) an acrylic monomer, a vinyl aromatic monomer or an acrylonitrile monomer graft polymerized to (1), said monomer units being selected from the group consisting of lower alkyl methacrylates, alicyclic methacrylates and alkyl acrylates, vinyl or substituted-vinyl aromatics or substituted aromatics, e.g., benzene or naphthalene rings, and/or acrylonitrile or substituted acrylonitriles, monomer graft polymerized to (1); sequentially or simultaneously with the polymerization of (1).
The graft polymerization product of an acrylic monomer alone or with, e.g., styrene monomer and/or with, e.g., acylonitrile and the rubbery diene polymer or copolymer may be prepared by known techniques, typically by emulsion polymerization. They may be formed from a styrene-butadiene copolymer latex or a butyl acrylate polymer latex and a monomeric material such as methyl methacrylate alone or with another compound, e.g., styrene alone, and/or with an acrylonitrile or substituted acrylonitrile. For example, in the preparation of a representative material, 85-65 parts by weight of monomeric methyl methacrylate or monomeric methyl methacrylate to the extent of at least 55% and preferably as much as 75% by weight in admixture with another monomer which copolymerizes therewith, such as ethyl acrylate, acrylonitrile, vinylidene chloride, styrene, and similar unsaturated compounds containing a single vinylidene group, is added to 15-35 parts by weight of solids in a styrene-butadiene copolymer latex. The copolymer solids in the latex comprise about 10-50% by weight of styrene and about 90-50% by weight of butadiene and the molecular weight thereof is within the range of about 25,000 to 1,500,000. The copolymer latex of solids in water contains a dispersing agent such as sodium oleate or the like to maintain the copolymer in emulsion. Interpolymerization of the monomer or monomeric mixture with the copolymer solids emulsified in water is brought about in the presence of a free-radical generating catalyst and a polymerization regulator which serves as a chain transfer agent, at a temperature of the order of 15° C. to 80° C. Coagulation of the interpolymerized product is then effected with a calcium chloride solution, for instance, whereupon it is filtered, washed and dried. Other graft copolymers and differing from the above only in the ratio of monomeric material solely or preponderantly of methyl methacrylate to the butadiene-styrene copolymer latex in the presence of which it is polymerized extends from 85-25 parts by weight of the former to 15-75 parts by weight of the latter. These materials may extend in physical properties from relatively rigid compositions to rubbery compositions. Also, U.S. Pat. No. 3,792,123, which is incorporated by reference, contain additional information as to the preparation of these materials. Other preferred commercially available materials are a styrene-butadiene graft copolymer designated Blendex 525 by Marbon Chemical Co.
In certain compositions herein, a three component graft copolymer comprising an acrylate, a styrene and a diene rubber backbone will be exemplified. This can be made following the foregoing teachings, and is also available from Rohm & Haas as the product designated Acryloid KM-611.
It is also possible to use the so-called "all acrylic impact modifiers" of the type designated Acryloid KM-323B by Rohm and Haas.
Other acrylic modifiers are those comprised of acrylic ester units and vinyl aromatic units, such as the butyl acrylate-styrene graft copolymers made by the procedures described, e.g., by Ito, et al, in Chemical Abstracts, Vol. 84, entry 84:5874 g., 1976.
In other compositions herein, a segmented copolyester will be exemplified. These are made following the general teachings of U.S. Pat. Nos. 3,023,182; 3,651,014; 3,763,109 and 3,766,146, each of which is incorporated herein by reference.
A preferred segmented thermoplastic copolyester is one that hardens rapidly from the molten state consisting essentially of a multiplicity of recurring long chain ester units and short chain ester units joined head-to-tail through ester linkages, said long chain ester units being represented by the formula: ##STR4## and said short chain units being represented by the formula: ##STR5## where G 2 is a divalent radical remaining after the removal of terminal hydroxyl groups from a poly(alkylene oxide) glycol having a melting point of less than about 60° C., a molecular weight of about 400-4000 and a carbon to oxygen ratio of about 2.5-4.3; R is a divalent radical remaining after removal of carboxyl groups from a dicarboxylic acid having a molecular weight less than about 300 and D 3 is a divalent radical remaining after removal of hydroxyl groups from a diol having a molecular weight less than about 250; provided,
(a) said short chain ester units amount to about 48-65% by weight of said copolyester.
(b) at least about 80% of the R groups in A and B are 1,4-phenylene radicals and at least about 80% of the D 3 groups in B are 1,4-butylene radicals, and
(c) the sum of the percentages of R groups which are not 1,4-phenylene radicals and of D 3 groups which are not 1,4-butylene radicals does not exceed about 20; also an additional type of copolyester is that as described hereinabove except that:
(a) said short chain ester units amount to about 66-95L % by weight of said copolyester.
(b) at least about 70% of the R groups in Formulas A and B are 1,4-phenylene radicals and at least about 70% of the D groups in Formula B are 1,4-butylene radicals, and
(c) the sum of the percentages of R groups in Formulas A and B which are not 1,4-butylene radicals does not exceed about 30.
The preferred materials are commercially available as Hytrel 4055 and Hytrel 5555 from E. I. duPont de Nemours and Company.
In certain compositions herein, a rubber modified vinyl aromatic compound comprising from 20 to 45 percent by weight of a diene rubber will be exemplified. Those can be made by intimately admixing, e.g., polystyrene and a polybutadiene rubber, and are also available commercially in a preferred embodiment from Union Carbide, product designated TDG-2100.
In certain compositions herein, a normally liquid polybutadiene oligomer will be exemplified. These can be made by conventional means, e.g., by alkali metal or organometallic catalyzed synthesis, to produce a low molecular weight polymer, e.g., of from 500 to 3000 or more, molecular weight, which is normally liquid as described, e.g., in U.S. Pat. No. 3,678,121, incorporated herein. Only a small amount of the butadiene oligomer is needed to improve Gardner (ductile) impact strength, e.g., 0.5 to 5% by weight, based on components (a), (b), (c) and (d). A preferred polybutadiene oligomer has a molecular weight of 2000 and a viscosity, at 50° C., of about 290 poise.
As noted above, the compositions of this invention can also include a polyphenylene ether resin. The polyphenylene ether resins are preferably of the formula: ##STR6## wherein the oxygen ether atom of one unit is connected to the benzene nucleus of the next adjoining unit, n is a positive integer and is at least 50 and each Q is a monovalent substituent selected from the group consisting of hydrogen, halogen, hydrocarbon radicals free of a tertiary alpha-carbon atom, halohydrocarbon radicals having at least two carbon atoms between the halogen atom and the phenyl nucleus, hydrocarbonoxy radicals and halohydrocarbonoxy radicals having at least two carbon atoms between the halogen atom and the phenyl nucleus.
Examples of polyphenylene ethers corresponding to the above formula can be found in Hay, U.S. Pat. No. 3,306,874 and 3,306,875 and in Stamatoff, U.S. Pat. No. 3,257,357 and 3,257,358, which are incorporated herein by reference.
For purposes of the present invention, an especially preferred family of polyphenylene ethers includes those having alkyl substitution in the two positions ortho to the oxygen ether atom, i.e., those of the above formula wherein each Q is alkyl, most preferably having from 1 to 4 carbon atoms. Illustrative members of this class are: poly(2,6-dimethyl-1,4-phenylene) ether; poly(2,6-diethyl-1,4-phenylene)ether; poly(2-methyl-6-ethyl-1,4-phenylene)ether; poly(2-methyl-6-propyl-1,4-phenylene) ether; poly(2,6-dipropyl-1,4-phenylene)ether; poly(2-ethyl-6-propyl-1,4-phenylene)ether; and the like. The most preferred polyphenylene ether resin is poly)2,6-dimethyl-1,4-phenylene)ether, preferably having an intrinsic viscosity of about 0.5 deciliters per gram as measured in chloroform at 25° C.
The components of the compositions of this invention are combinable in a wide range of proportions. The compositions can comprise, for instance, from about 5 to about 95, preferably from about 40 to about 90 parts by weight of (a) the copolymer of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride, and from about 95 to about 5, preferably from about 60 to about 10, parts by weight of (b) the impact modifier.
When a polyphenylene ether resin is also used, the compositions will preferably include from about 5 to about 95, preferably from about 40 to about 90 parts by weight of the copolymers of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride, from about 95 to about 5, preferably from about 60 to about 10 parts by weight of the impact modifier (b), and preferably from about 1 to about 75 parts by weight of a polyphenylene ether resin.
The compositions of the invention can also include other ingredients, such as flame retardants, extenders, processing aids, pigments, stabilizers and the like, for their conventionally employed purposes. Reinforcing fillers, in amounts sufficient to impart reinforcement, can be used, such as aluminum, iron or nickel, and the like, and non-metals, such as carbon filaments, silicates, such as acicular calcium silicate, and platey magnesium or aluminum silicates, asbestos, titanium dioxide, potassium titanate and titanate whiskers, glass flakes and fibers.
The preferred reinforcing fillers are of glass. In general, best properties will be obtained if glass filaments are employed in amounts of from about 10 to about 40% by weight, based on the combined weight of glass and resin. However, higher amounts can be used.
The compositions of the invention may be prepared by blending the components in a Henschel mixer and compounding the mixture on a twin-screw 28 mm Werner-Pfleiderer extruder. Thereafter, the extrudate is chopped into pellets and molded on a Newbury injection molding machine.
The present invention is further illustrated in the following examples, which are not to be construed as limiting. All parts are by weight.
EXAMPLES 1-4
Blends of styrene-maleic anhydride copolymers, acrylic unit containing impact modifying polymer and poly(2,6-dimethyl-1,4-phenylene)ether resin are prepared by blending the components in a Henschel mixer and thereafter compounding the mixture on a twin-screw 28 mm Werner-Pfleiderer extruder. Thereafter the extrudate is chopped into pellets and molded on a Newbury injection molding machine. The formulations and test results are set forth in Table 1.
TABLE 1______________________________________Compositions Comprising Styrene/MaleicAnhydride Copolymer and Acrylic Graft Copolymer Example 1 1A* 2 3 4 4A*______________________________________Composition(parts by weight)Styrene-Maleic anhydride 70 100 60 -- -- --copolymer.sup.aStyrene-Maleic anhydride -- -- -- 80 70 100Copolymer (rubbermodified).sup.bAcrylic ester impact 30 -- 30 20 20 --modifier.sup.cpoly(2,6-dimethyl-1,4- -- -- 10 -- 10 --phenylene ether.sup.dPropertiesTensile yield, psi 7500 9300 7600 6700 7200 7800Tensile strength, psi 7500 9300 7600 5000 5800 6400Elongation, % 8 9 11 28 50 31Izod impact, ft.-lbs./in. 0.5 0.4 0.6 2.1 3.2 1.8notchGardner impact, in-lbs. <10 <10 42 20 50 <10Heat distortion tempera- 212 210 224 210 222 212ture at 266 psi, °F.______________________________________ *Control .sup.a Dylark 232, Arco Chemicals .sup.b Dylark 240, Arco Chemicals .sup.c Acryloid XM 323B Rohm & Haas .sup.d PPO, General Electric Company
Especially noteworthy is the ability of the impact modifier to upgrade the impact properties of the unmodified styrene/maleic anhydride copolymer when used in conjunction with the polyphenylene ether. The impact properties of the rubber modified styrene/maleic anhydride copolymer is efficiently upgraded with the impact modifier in the presence and absence of polyphenylene ether.
EXAMPLES 5-6
The procedure of Examples 1-4 are repeated, substituting a graft copolymer of styrene and polybutadiene rubber. A graft copolymer comprising styrene-methyl methacrylate and polybutadiene rubber is included for comparison purposes. The formulations used and property data obtained are summarized in Table 2.
TABLE 2______________________________________Compositions Comprising Styrene/Maleic AnhydrideCopolymer and Styrene-Polybutadiene Graft Copolymers Example 5A* 5 6 6A* 6B*______________________________________Composition (parts by weight)Styrene-maleic anhydride 100 70 60 70 60copolymer.sup.aStyrene-polybutadiene -- 30 30 -- --graft polymer.sup.cStyrene-methyl methacrylate -- -- -- 30 30polybutadiene graft polymer.sup.cPoly(2,6-dimethyl-1,4-phenylene -- -- 10 -- 10ether.sup.dPropertiesTensile yield, psi 9300 5900 6300 7900 7900Tensile strength, psi 9300 5600 5800 5600 5900Elongation, % 9 21 18 20 23Izod impact, ft.-lbs/in. notch 0.43 1.4 3.2 0.69 0.67Gardner impact, in.-lbs. <10 33 32 <10 <10Heat distortion temp. at 218 205 219 212 225266 psi, °F.______________________________________ *Controls .sup.a Dylark 232, Arco Chemicals .sup.b Blendex 525, Marbon Chemicals .sup.c Acryloid KM611, Rohm & Haas .sup.d PPO, General Electric Company
The improvement in toughness of crystal grades of styrene-maleic anhydride is especially marked with the graft copolymer of styrene-polybutadiene.
EXAMPLES 7-8
The general procedure of Examples 1-4 is used to formulate, mold and test compositions which include a normally liquid polybutadiene oligomer as a ductile impact (Gardner) modifier. The formulations and properties are set forth in Table 3.
TABLE 3______________________________________Composition Comprising Styrene-Maleic Anhydride Copolymer,Segmented Copolyester or Acrylic-Styrene-Diene Rubber Graft,Polyphenylene Ether and Polybutadiene Oligomer Example 7 7A* 8 8A*______________________________________Composition (parts by weight)Styrene-maleic anhydride 70 70 70 70copolymer (rubber modified).sup.aSegmented Copolyester of Poly 20 20 -- --(1,4-butylene-propyleneglycol) terephthlate.sup.bStyrene-methyl methacrylate -- -- 20 20polybutadiene graft.sup.cPoly(2,6-dimethyl-1,4-phenylene 10 10 10 10ether).sup.dLiquid polybutadiene Oligomer.sup.e 1 -- 1 --PropertiesTensile yield, psi 7100 7500 7200 7600Tensile strength, psi 5800 7400 5600 5900Elongation, % 25 9 39 38Gardner impact, in.-lbs. 65 7 135 83______________________________________ *Control .sup.a Dylark 240, Arco Chemicals .sup.b Hytrel 5555, Dupont Co. .sup.c Acryloid KM611, Rohm & Haas .sup.d PPO, General Electric Co. .sup.e Molecular weight 2000, viscosity at 50° C., 290 poise
EXAMPLES 9-10
The general procedure of Examples 1-4 is used to formulate, mold and test compositions which include a normally liquid polybutadiene oligomer as a ductile impact (Gardner) modifier. The formulations and properties are set forth in Table 4:
TABLE 4______________________________________Compositions Comprising Styrene/Maleic Anhydride Copolymer,Rubber Modified Polystyrene or Styrene-Butadiene GraftCopolymer, Polyphenylene Ether and Polybutadiene Oligomer Example 9 9A* 10 10A*______________________________________Composition (parts by weight)Styrene-maleic anhydride copolymer 60 60 70 70(rubber modified).sup.aRubber modified Polystyrene.sup.b 30 30 -- --Styrene-polybutadiene -- -- 20 20graft copolymer.sup.cPoly(2,6-dimethyl-1,4-phenylene 10 10 10 10ether resin.sup.dLiquid polybutadiene Oligomer.sup.e 1 -- 1 --PropertiesTensile yield, psi 5900 5800 6500 6700Tensile strength, psi 5300 5300 5600 5800Elongation, % 50 48 36 39Gardner impact, in.-lbs. 49 19 85 20______________________________________ *Control .sup.a Dylark 240, Arco Chemicals .sup.b TGD2500 25% rubber, Union Carbide .sup.c Blendex 525, Marbon Chemicals .sup.d PPO, General Electric Co. .sup.e Molecular weight 2000, viscosity at 50° C., 290 poise.
In Examples 7-10, the addition of only 1% of liquid polybutadiene oligomer improves the Gardner impact strength at least one and one-half times.
EXAMPLE 11
A styrene-maleic anhydride copolymer containing 15 mole % of maleic anhydride is blended 50:50 with poly(2,6-dimethyl-1,4-phenylene ether). After molding and testing it is found that the heat distortion temperature is 40° F. higher than that of a corresponding composition comprising 50:50 of polystyrene and poly(2,6-dimethyl-1,4-phenylene ether. A similar composition in which the anhydride function has been pre-reacted with aniline has only a slightly lower heat distortion temperature, but higher than the polystyrene comparison composition.
Obviously, many variations will suggest themselves to those skilled in the art, in view of the above detailed disclosure. All such variations are within the full intended scope of the appended claims. | Thermoplastic molding compositions are disclosed which comprise an intimate admixture of (a) a copolymer of a vinyl aromatic compound and an α,β-unsaturated cyclic anhydride, including rubber-modified copolymers thereof, and (b) impact modifiers comprising graft copolymers, copolyesters, and rubber-modified homopolymers. Optionally, the compositions can also include a polyphenylene ether resin and further, optionally, a normally liquid polybutadiene oligomer. Mixing (a) with a polyphenylene ether leads to a compatible composition, markedly improved in heat deflection temperature. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1) Field of the Invention
[0002] The subject invention generally relates to a lignocellulosic composite material and a method for preparing the lignocellulosic composite material. The subject invention also generally relates to a binder resin having at least one of an insecticide and a fungicide therein for forming the composite material.
[0003] 2) Description of Related Art
[0004] Composite materials, such as oriented strand board (OSB), medium density fiberboard (MDF), agrifiber board, particle board, flakeboard, and laminated strand board (LVL) are known in the art. Generally, these types of boards are produced by blending or spraying lignocellulosic particles or materials with a binder resin while the lignocellulosic particles are tumbled or agitated in a blender or like apparatus. Lignocellulosic particles generally refer to wood particles as appreciated by those skilled in the art. After blending sufficiently to form a uniform mixture, the particles are formed into a loose mat, which is compressed between heated platens or plates, or by steam injection between the two platens to cure the binder and bond the flakes, strands, strips, pieces, etc., together in densified form. Conventional processes are generally carried out at temperatures of from about 120 to 225° C. in the presence of varying amounts of steam, either purposefully injected into or generated by liberation of entrained moisture from the wood or lignocellulosic particles. These processes also generally require that the moisture content of the lignocellulosic particles be between about 1 and about 20% by weight, before it is blended with the binder resin to produce adequate physical properties of the composite material.
[0005] The lignocellulosic particles can be in the form of chips, shavings, strands, wafers, fibers, sawdust, bagasse, straw, wood wool, bamboo and the like, depending upon the type of composite material desired to be formed. When the particles are larger, the boards produced by the process are known in the art under the general term of engineered wood. These engineered woods include panels, plywood, laminated strand lumber, OSB, parallel strand lumber, and laminated veneer lumber. When the lignocellulosic particles are smaller, the boards are known in the art as particleboard and fiber board.
[0006] The engineered wood products were developed due to the increasing scarcity of suitably sized tree trunks for cutting lumber. Such products can have advantageous physical properties such as strength and stability. Another advantage of the engineered wood and particle boards is that they can be made from the waste material generated by processing other wood and lignocellulosic materials. This leads to efficiencies and energy savings from recycling processes, and saves landfill space.
[0007] Binder resin compositions that have been used in making such composite wood products include phenol formaldehyde resins, urea formaldehyde resins, melamine urea formaldehyde, and isocyanates resins. Isocyanate binders are commercially desirable because they have low water absorption, high adhesive and cohesive strength, flexibility in formulation, versatility with respect to cure temperature and rate, excellent structural properties, the ability to bond with lignocellulosic materials having high water contents, and no additional formaldehyde emissions from resin. The disadvantages associated with the use of isocyanates include difficulty in processing due to their high reactivity, too much adhesion to platens, lack of cold tack, high cost and the need for special storage.
[0008] It is known to treat lignocellulosic materials with polymeric diphenylmethane diisocyanate (polymeric MDI or PMDI) to improve the strength of the composite material. Typically, such treatment involves applying the isocyanate to the material and allowing the isocyanate to cure, either by application of heat and pressure or at room temperature. While it is possible to allow the polymeric MDI to cure under ambient conditions, residual isocyanate groups remain on the treated products for weeks or even months in some instances. It is also known, but generally less acceptable from an environmental standpoint, to utilize toluene diisocyanate for such purposes. Isocyanate prepolymers are among the preferred isocyanate materials that have been used in binder compositions to solve various processing problems, particularly adhesion to press platens and high reactivity.
[0009] In the past, various solvents have been added to binder resin with the aim of achieving a lower viscosity and better handling properties. After application, the solvent evaporates during the molding process, leaving the bound particles behind. One major disadvantage of prior art solvents is that they cause a reduction in the physical properties of the formed board including a reduction in the internal bond strength of the formed board.
[0010] Separately from the formulation of improved lignocellulosic composite materials, it is desirable to prevent insects from damaging the composite materials over time and during normal use. Those skilled in the art of insecticides have developed numerous insecticides that are capable of killing or intoxicating various insects once they are exposed to the insecticide.
[0011] While these insecticides have been very commercially successful in the agricultural applications, typical applications have encountered difficulty in applying them in lignocellulosic composite materials. Various methods have been employed to incorporate these insecticides into the wooden structures discussed above and any other wooden article. For example, various prior art methods dissolve an insecticide in a solvent, such as water, and spray the solution onto the wooden structure. The solvent then absorbs into the wood and prevents the insects from damaging the wooden structure. However, one drawback with spraying the solution on wood that is already formed is that over time, the insects will eat away at the wood and eventually get beyond the point where the solution has absorbed. At this point, the wooden structure is vulnerable to subsequent attacks by insects. Another drawback to this method is that any additional water added during formation of the composite material reduces the physical properties of the final composite material. During the pressing stage, steam pressure from any water present in the composite material tends to reduce the physical properties. Therefore, adding additional water would increase the steam pressure and further reduce the physical properties. Additionally, it is typical to dry the wood strands to lower moisture content at the beginning to minimize this effect, but this additional drying costs energy and time.
[0012] Other methods, especially used in the formation of plywood, include incorporating a powder insecticide directly into a glue or an adhesive. Plywood, or laminated veneer, is prepared by applying glue to an already formed layer of wood and compressing it together with another layer of wood. The glue, having the insecticide therein, is applied between the layers of the wood and is compressed to form the plywood. However, the insecticide is not present, i.e., dispersed, throughout the wood, since it is only located in the glue between the layers. Therefore, it is possible to have an initial infestation of insects eat through the glue layer exposing the unprotected wood underneath. Subsequent infestations of insects are then able to cause substantial damage because the insecticide has been removed. In this method, the plywood has not been made insect resistant, only the glue is insect resistant.
[0013] Still other methods have incorporated the insecticide by encapsulating the insecticide in a polyurethane. It is known that the dispersibility and dissolvability of certain insecticides, such as fipronil, is difficult to achieve in certain substances, such as water. Therefore, encapsulating the insecticide in polyurethane improves the dispersibility of the insecticide. However, the encapsulation restricts the direct contact of the insecticide with the insect and requires the insect, in addition to eating the wood, to eat through the polyurethane prior to reaching the insecticide. Therefore, encapsulating the insecticide is not desirable. Further, the additional steps required to encapsulate the insecticide increase the time and cost of production, which are commercially unacceptable.
[0014] Fungicides have also been used to treat lignocellulosic composite materials. Fungicides are substances possessing the power of killing or preventing the growth of fungus. Therefore, the fungicides reduce the likelihood that the composite material will decay as a result of fungus over time. However, the application of the fungicide has been limited in similar circumstances as the insecticides discussed above.
[0015] Accordingly, it would be advantageous to provide a lignocellulosic composite material that is insect and fungus resistant and that is capable of withstanding insect attacks over a longer period of time to prevent insect damage to the composite material. The related art methods that only apply the insecticide to the surface of the wood or in the adhesive layers between the wood are subject to subsequent insect attacks after the insecticide layer has been breached. Therefore, it is desirable to produce a lignocellulosic composite material that has the insecticide present in a low dosage and dispersed throughout the composite material for preventing insect attacks.
BRIEF SUMMARY OF THE INVENTION
[0016] The subject invention provides a lignocellulosic composite material formed from lignocellulosic particles and a binder resin. The lignocellulosic particles are used in an amount of from about 75 to 99.5 parts by dry weight based on 100 parts by weight of the composite material and the binder resin is used in an amount of from 0.5 to 25 parts by weight based on 100 parts by weight of the composite material. The binder resin comprises a polyisocyanate and at least one of an insecticide and a fungicide. The insecticide and the fungicide are dispersed throughout the polyisocyanate, which is then dispersed throughout the lignocellulosic particles. Since the insecticide and the fungicide are dispersed throughout the composite material, the composite material is insect resistant and/or fungus resistant to withstand a subsequent insect attacks and prevent fungus growth and decay.
[0017] The binder resin more specifically includes the polyisocyanate, a polar solvent, and the insecticide that is dissolved in the polar solvent to form an insecticide solution. The polar solvent is capable of dissolving at least 10 grams of the insecticide per one liter of the polar solvent. The insecticide solution is dispersed throughout the polyisocyanate to form the binder resin. Next, a lignocellulosic mixture is formed that comprises the lignocellulosic particles and the binder resin. The lignocellulosic composite material is formed by compressing the lignocellulosic mixture at an elevated temperature and under pressure.
[0018] The subject invention provides a lignocellulosic composite material having at least one of the insecticide and the fungicide dispersed throughout the composite material. The resultant composite material is insect and/or fungus resistant. The composite material is able to repel insect attacks and fungus decay throughout the life of the composite material. Since the insecticide is dispersed throughout, an initial infestation of insects is not able to breach an insecticide layer and any subsequent infestations of insects will suffer the same fate as that of the first. Therefore, the lignocellulosic composite material of the present invention enjoys a longer period of life because it is insect resistant.
DETAILED DESCRIPTION OF THE INVENTION
[0019] A lignocellulosic composite material and a method for preparing the lignocellulosic composite material are disclosed. The composite material includes lignocellulosic particles and a binder resin. Throughout the present specification and claims, the terms compression molded, compressed, or pressed are intended to refer to the same process whereby the material is formed by either compression molding the material in a mold or by using compression as between a pair of plates from a press. In both procedures, pressure and heat are used to form the material and to set the binder resin.
[0020] The lignocellulosic particles can be derived from a variety of sources. They can be derived from wood and from other products such as bagasse, straw, flax residue, nut shells, cereal grain hulls, and mixtures thereof. Non-lignocellulosic materials in flake, fibrous or other particulate form, such as glass fiber, mica, asbestos, rubber, plastics and the like, can be mixed with the lignocellulosic material. The lignocellulosic particles can come from the process of comminuting small logs, industrial wood residue, branches, or rough pulpwood into particles in the form of sawdust, chips, flakes, wafer, strands, medium density fibers (MDF), and the like. They can be prepared from various species of hardwoods and softwoods. The lignocellulosic particles may have a moisture content of from 1 to 15 weight percent. In a further preferred embodiment, the water content is from 3 to 12 weight percent, and most preferably from 4 to 10 weight percent. The water assists in the curing or setting of the binder resin, which is described further below. Even when the lignocellulosic particles are dried, they typically still have a moisture content of from 2 to 15 weight percent.
[0021] The lignocellulosic particles can be produced by various conventional techniques. For example, pulpwood grade logs can be converted into flakes in one operation with a conventional roundwood flaker. Alternatively, logs and logging residue can be cut into fingerlings on the order of about 0.5 to 3.5 inches long with a conventional apparatus, and the fingerlings flaked in a conventional ring type flaker. The logs are preferably debarked before flaking.
[0022] The dimensions of the lignocellulosic particles are not particularly critical. Flakes commonly have an average length of about 2 to 6 inches, and average width of about 0.25 to 3 inches, and an average thickness of about 0.005 to about 0.05 inches. Strands which are about 1.5 inches wide and 12 inches long can be used to make laminated strand lumber, while strands about 0.12 inches thick and 9.8 inches long can be used to make parallel strand lumber. The lignocellulosic particles can be further milled prior to use in the process of the invention, if such is desired to produce a size more suitable for producing the desired article. For example, hammer, wing beater, and toothed disk mills may be used.
[0023] In the subject invention, the lignocellulosic particles are present in an amount of from about 75 to 99.5 parts by dry weight based on 100 parts by weight of the composite material, preferably from about 80 to 99.5 parts by dry weight based on 100 parts by weight of the composite material, and most preferably 85 to 99.5 parts by dry weight based on 100 parts by weight of the composite material.
[0024] The binder resin includes a polyisocyanate and at least one of an insecticide and a fungicide. The binder resin is present in an amount of from 0.5 to 25 parts by weight based on 100 parts by weight of the composite material, whereby the remainder is the lignocellulosic particles. However, it is to be appreciated that other additives may be added, such as wax, flame retardant, and the like. In a preferred embodiment, the binder resin is present in an amount of from 0.5 to 20, and more preferably from 1 to 20 parts by weight based on 100 parts by weight of the composite material, and most preferably from 2 to 15 parts by weight based on 100 parts by weight of composite material.
[0025] The polyisocyanate that may be used in forming the binder resin includes aliphatic, alicyclic and aromatic polyisocyanates characterized by containing two or more isocyanate groups. Such polyisocyanates include the diisocyanates and higher functionality isocyanates, particularly the aromatic polyisocyanates. Mixtures of polyisocyanates which may be used include, crude mixtures of di- and higher functionality polyisocyanates produced by phosgenation of aniline-formaldehyde condensates or as prepared by the thermal decomposition of the corresponding carbamates dissolved in a suitable solvent, as described in U.S. Pat. No. 3,962,302 and U.S. Pat. No. 3,919,279, the disclosures of which are incorporated herein by reference, both known as crude diphenylmethane diisocyanate (MDI) or polymeric MDI (PMDI). The polyisocyanate may be an isocyanate-terminated prepolymer made by reacting, under standard conditions, an excess of a polyisocyanate with a polyol which, on a polyisocyanate to polyol basis, may range from about 20:1 to 2:1. The polyols include, for example, polyethylene glycol, polypropylene glycol, diethylene glycol monobutyl ether, ethylene glycol monoethyl ether, triethylene glycol, etc., as well as glycols or polyglycols partially esterified with carboxylic acids including polyester polyols and polyether polyols.
[0026] The polyisocyanates or isocyanate-terminated prepolymers may also be used in the form of an aqueous emulsion by mixing such materials with water in the presence of an emulsifying agent. The isocyanate compound may also be a modified isocyanate, such as, carbodiimides, allophanates, isocyanurates, and biurets.
[0027] Also illustrative of the di- or polyisocyanates which may be employed are, for example: toluene-2,4- and 2,6-diisocyanates or mixtures thereof; diphenylmethane-4,4′-diisocyanate and diphenylmethane-2,4′-diisocyanate or mixtures of the same, the mixtures preferably containing about 10 parts by weight 2,4′- or higher, making them liquid at room temperature; polymethylene polyphenyl isocyanates; naphthalene-1,5-diisocyanate; 3,3′-dimethyl diphenylmethane-4,4′-diisocyanate; triphenyl-methane triisocyanate; hexamethylene diisocyanate; 3,3′-ditolylene-4,4-diisocyanate; butylene 1,4-diisocyanate; octylene-1,8-diisocyanate; 4-chloro-1,3-phenylene diisocyanate; 1,4-, 1,3-, and 1,2-cyclohexylene diisocyanates; and, in general, the polyisocyanates disclosed in U.S. Pat. No. 3,577,358, the disclosure of which is incorporated herein by reference. Preferred polyisocyanates include polymeric diphenylmethyl diisocyanate and monomeric diphenylmethane diisocyanate being at least one of diphenylmethane-4,4′-diisocyanate, diphenylmethane-2,4′-diisocyanate, and diphenylmethane-2,2′-diisocyanate. Most preferably, the polyisocyanate component is polymeric diphenylmethyl diisocyanate. One example of a preferred polyisocyanate is, but is not limited to, Lupranate® M20 S, commercially available from BASF Corporation.
[0028] The polyisocyanate is present in the binder resin in an amount of from about 60 to 99.99 parts by weight based on 100 parts by weight of the binder resin. In a preferred embodiment, the polyisocyanate is present in an amount of from about 80 to 99.9 parts by weight based on 100 parts by weight of the binder resin, and most preferably from about 90 to 99.9 parts by weight based on 100 parts by weight of the binder resin.
[0029] Preferably, the insecticide is dissolved in a polar solvent to form an insecticide solution. The insecticide solution is then mixed with the polyisocyanate to form the binder resin with well-dispersed insecticide. It is to be appreciated that the fungicide may also be dissolved in the polar solvent to ensure that it is well dispersed. This mixing process may occur right before applying the resin to the wood substrates, such as using in-line mixing techniques before feeding the resin mixture into the blending equipment. The polar solvent is capable of dissolving at least 10 grams of the insecticide per one liter of the polar solvent.
[0030] In order to ensure that a sufficient amount of insecticide is added without adding too much polar solvent, the dissolvability of the insecticide is important. It is desirable to only add a low dosage of the insecticide that is sufficient to repel insect attacks. Therefore, it is important to ensure the low dosage is distributed throughout. If the solvent is capable of dissolving only less than 10 grams, then in order to have enough of the insecticide, more solvent would be needed. This creates the problem that the lignocellulosic composite material will not have sufficient physical properties, such as modulus of elasticity. When the lignocellulosic composite material is formed under elevated temperature, the solvent evaporates from the mixture. If too much solvent in added, the evaporating solvent creates a steam pressure within the forming lignocellulosic composite material and it hinders the physical properties.
[0031] It has been determined that certain polar solvents are capable of dissolving at least 10 grams of the insecticide per liter of solvent. For example, it has also been determined that water is not a sufficient polar solvent for certain insecticides, such as Fipronil, because it is capable of only dissolving 2.4 milligrams per liter of water. Generally, these polar solvents that are capable of dissolving at least 10 grams of the insecticide per liter are selected from at least one of an alcohol, a ketone, and an ester. More preferably, the polar solvent is selected from the group of octyl alcohol, isopropyl alcohol, methyl alcohol, acetone, carpryl alcohol, propylene carbonate, gamma-butyrolactone, 3-pentanone, 1-methyl-2-pyrrolidinone, and combinations thereof.
[0032] The insecticide is selected from at least one of the following: pyrazole insecticides, pyrrole insecticides, pyrethroid insecticides, amidinohydrazone insecticides, semicarbazone insecticides, and neo-neo-nicotinoid insecticides. In other words, the insecticide may be a pyrazole insecticide or a pyrrole insecticide, etc. The insecticide may also be a mixture or combination of these insecticides. Each of these insecticides attacks the insects in a different manner and is not intended to limit the subject invention. One example of a pyrrole insecticide is, but not limited to, chlorfenapyr. One example of a pyrethroid insecticide, is, but not limited to alphacypermethrin. One example of an amidinohydrazone insecticide, is, but not limited to hydramethylnon. One example of a semicarbazone insecticide, is, but not limited to BAS 320-I. One example of a neo-neo-nicotinoid insecticide is, but not limited to imidacloprid.
[0033] The pyrazole insecticide is typically available and used in at least one of a powder form and a granular form prior to being dissolved in the polar solvent. It is preferred that the pyrazole insecticide is an aryl pyrazole compound having the general formula of:
wherein Z 1 may be an alkly or an aryl group, Z 2 is an amine, an alkyl, or a hydrogen, Z 3 is a sulfoxide and haloaklyl, and Z 4 is CN or methyl. Further, the aryl pyrazole may open the aromatic pentane ring to form the insecticide. The pyrazole insecticide may be selected from one of fipronil, ethiprole or acetaprole and combinations thereof.
[0035] More preferably, the pyrazole insecticide has the general formula of:
wherein R 1 is one of CN and methyl, R 2 is S(O) n A, wherein A is a haloaklyl and n is 0, 1, or 2, R 3 is one of H, NH 2 , and alkyl, R 4 is an haloaklyl, R 5 is a halogen, and R 6 is a halogen.
[0037] Most preferably, the pyrazole insecticide is fipronil (5-amino-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-4-((trifluoromethyl)sulfinyl)-1H-pyrazole-3-carbonitrile) having the formula of C 12 H 4 Cl 2 F 6 N 4 OS and the following structure:
[0038] The insecticide is present in an amount of from 0.001 to 10, preferably from 0.001 to 5, and most preferably from 0.001 to 2.5 parts by weight based on 100 parts by weight of the binder resin. The polar solvent is present in an amount of from 0.1 to 20 parts by weight based on 100 parts by weight of the binder resin. However, it is to be appreciated that the amount of the polar solvent depends upon the dissolvability of the insecticide in the polar solvent. Therefore, more of the polar solvent will be required if it can dissolve 10 grams of the insecticide per liter than if the polar solvent can dissolve 600 grams per liter.
[0039] Typical examples of fungicides that may be utilized with the subject invention include, but are not limited to, triazoles, benzimidazoles, morpholines, dicarboxamides or strobilurines. The fungicide may be added directly to the polyisocyanate or may be dissolved in the polar solvent as discussed above. Dissolving the fungicide in the polar solvent ensures the fungicide is well dispersed throughout the composite material. The fungicide is present in an amount of from 0.001 to 10, preferably from 0.001 to 5, and most preferably from 0.001 to 2.5 parts by weight based on 100 parts by weight of the binder resin. The method of forming the lignocellulosic composite material includes the steps of dispersing at least one of the insecticide and the fungicide in the polyisocyanate to form the binder resin. As discussed above, the insecticide may be dissolved in the polar solvent capable of dissolving at least 10 grams of the insecticide per one liter of the polar solvent to form the insecticide solution, which is then mixed with the polyisocyanate to form the binder resin. The insecticide is added in an amount of from 1 to 500 parts per million (PPM) based on dry weight of the lignocellulosic particles, preferably from 10 to 300, and most preferably from 20 to 250 parts per million based on dry weight of the lignocellulosic particles. The polyisocyanate is present in an amount of from 0.5 to 25 parts by weight based on 100 parts by dry weight of the lignocellulosic material.
[0040] After the binder resin is formed, the lignocellulosic mixture is formed by combining from about 75 to 99.5 parts by weight of the lignocellulosic particles based on 100 parts by weight of the lignocellulosic mixture with the binder resin in an amount of from 0.5 to 25 parts by weight based on 100 parts by weight of the lignocellulosic mixture. The lignocellulosic particles are resinated using the binder resin described above. The binder resin and the lignocellulosic particles are mixed or milled together during the formation of a resinated lignocellulosic mixture. Generally, the binder resin can be sprayed onto the particles while they are being agitated in suitable equipment. To maximize coverage of the particles, the binder resin is preferably applied by spraying droplets of the binder resin onto the particles as they are being tumbled in a rotary blender or similar apparatus. For example, the particles can be resinated in a rotary drum blender equipped with at least one spinning disk atomizer.
[0041] For testing on a lab scale, a simpler apparatus can suffice to resinate the particles. For example, a 5 gallon can is provided with baffles around the interior sides, and a lid with a hole large enough to receive the nozzle of a spray gun or other liquid delivery system, such as a pump sprayer. It is preferred that the binder resin be delivered as a spray. The particles to be resinated are placed in a small rotary blender. The blender is rotated to tumble the particles inside against the baffles, while the desired amount of binder resin is delivered with a spray device. After the desired amount of binder resin is delivered, the particles can be tumbled for a further time to effect the desired mixing of the particles with the binder resin.
[0042] The amount of binder resin to be mixed with the lignocellulosic particles in the resinating step is dependant upon several variables including, the binder resin used, the size, moisture content and type of particles used, the intended use of the product, and the desired properties of the product. The mixture produced during the resinating step is referred to in the art as a furnish. The resulting furnish, i.e., the mixture of flakes, binder resin, parting agent, and optionally, wax, wood preservatives and/or other additives, is formed into a single or multi-layered mat that is compressed into a particle board or flakeboard panel or another composite article of the desired shape and dimensions. The mat can be formed in any suitable manner. For example, the furnish can be deposited on a plate-like carriage carried on an endless belt or conveyor from one or more hoppers spaced above the belt. When a multi-layer mat is formed, a plurality of hoppers are used with each having a dispensing or forming head extending across the width of the carriage for successively depositing a separate layer of the furnish as the carriage is moved between the forming heads.
[0043] The lignocellulosic composite material may be formed of a single mat, or layer, having a thickness of from 0.1 inches to 2 feet with the insecticide and/or the fungicide dispersed throughout the layer, or formed of a plurality of mats, or layers, with each of the plurality of layers having a thickness of from 0.1 inches to 6 inches with the insecticide and/or the fungicide dispersed throughout each of the plurality of layers. The mat thickness will vary depending upon such factors as the size and shape of the wood flakes, the particular technique used in forming the mat, the desired thickness and density of the final product and the pressure used during the press cycle. The mat thickness usually is about 5 to 20 times the final thickness of the article. For example, for flakeboard or particle board panels of ½ to ¾ inch thickness and a final density of about 35 lbs/ft 3 , the mat usually will be about 0.1 to 6 inches thick.
[0044] Finally, the lignocellulosic composite material is formed by compressing the lignocellulosic mixture at an elevated temperature and under pressure. Press temperatures, pressures and times vary widely depending upon the shape, thickness and the desired density of the composite article, the size and type of wood flakes, the moisture content of the wood flakes, and the specific binder used. The press temperature can be from about 100° to 300° C. To minimize generation of internal steam and the reduction of the moisture content of the final product below a desired level, the press temperature preferably is less than about 250° C. and most preferably from about 180° to about 240° C. The pressure utilized is generally from about 100 to about 1000 pounds per square inch. Preferably the press time is from 50 to 350 seconds. The press time utilized should be of sufficient duration to at least substantially cure the binder resin and to provide a composite material of the desired shape, dimension and strength. For the manufacture of flakeboard or particle board panels, the press time depends primarily upon the panel thickness of the material produced. For example, the press time is generally from about 200 to about 300 seconds for a pressed article with a ½ inch thickness.
[0045] The following examples, illustrating the formation of the lignocellulosic composite material, according to the subject invention and illustrating certain properties of the lignocellulosic composite material, as presented herein, are intended to illustrate and not limit the invention.
EXAMPLES
[0046] The following examples describe the formation of a lignocellulosic composite material by adding and reacting the following parts.
TABLE 1 Example 1 Example 2 Example 3 Example 4 Amount, Amount, Amount, Amount, gm Pbw gm Pbw gm Pbw gm Pbw Binder Resin 283.83 3.0 282.52 3.1 1182.44 4.8 1183.58 4.8 Polyisocyanate 282.42 — 282.24 — 1181.29 — 1181.29 — Insecticide 1.41 — 0.28 — 1.15 — 2.29 — Lignocellulosic 9076.38 97.0 9076.38 97.0 0.0 0.0 0.0 0.0 Particles A Lignocellulosic 0.0 0.0 0.0 0.0 24566.56 95.2 24425.95 95.2 Particles B Total 9360.21 100.0 9358.90 100.0 25749.0 100.0 25609.53 100.0
[0047] The polyisocyanate is LUPRANATE® M20SB, commercially available from BASF Corporation. The pyrazole insecticide is fipronil. The lignocellulosic particles A are a southern yellow pine mix having a moisture content of about 8.27%. The lignocellulosic particles B are Aspen particles having an average moisture content of about 6.76%.
[0048] In Examples 1 and 2, the lignocellulosic composite material was formed having a thickness of 0.437 inches with a density of about 39 lb/ft 3 . In Example 1, 1.41 grams of fipronil were dissolved in 5.03 grams of the polar solvent to form the insecticide solution. The fipronil was present in an amount of about 150 PPM based on the dry weight of the lignocellulosic particles. In Example 2, 0.28 grams of fipronil were dissolved in 1.00 grams of the polar solvent to form the insecticide solution. The fipronil was present in an amount of about 30 PPM based on the dry weight of the lignocellulosic particles. The polar solvent was 1-methyl-2-pyrrolidinone (NMP). NMP is capable of dissolving about 289 grams of fipronil per liter of NMP.
[0049] In Examples 3 and 4, the lignocellulosic composite material was formed having a thickness of 0.719 inches with a density of about 40 lb/ft 3 . In Example 3, 1.15 grams of fipronil were dissolved in 5 grams of the polar solvent to form the insecticide solution. The fipronil was present in an amount of about 50 PPM based on the dry weight of the lignocellulosic particles. In Example 4, 2.29 grams of fipronil were dissolved in 10 grams of the polar solvent to form the insecticide solution. The fipronil was present in an amount of about 100 PPM based on the dry weight of the lignocellulosic particles. The polar solvent in Examples 3 and 4 was 3-pentanone, which is capable of dissolving about 326 grams of fipronil per liter of 3-pentanone.
[0050] The insecticide solutions formed in each of the examples was then added to the polyisocyanate component to form the binder resin and the binder resin was then mixed with the lignocellulosic particles. The lignocellulosic particles were pressed under elevated temperature and pressure to form the composite materials. The composite materials were then tested to determine the insecticide potency based upon the number of days after treatment (DAT) with the results listed below as the mean percent knockdown or mortality at DAT.
TABLE 2 Example 1 Example 2 Example 3 Example 4 Control Eastern Subterranean Termite 1 DAT 51.1 7.7 0.0 4.9 1.1 2 DAT 75.0 44.0 16.1 46.2 1.1 3 DAT 89.8 82.4 74.1 79.2 1.1 4 DAT 95.5 98.9 93.9 89.4 1.7 5 DAT 96.6 100.0 90.9 95.8 1.7 6 DAT 97.7 — 96.0 97.7 1.7
[0051] The insecticidal potency of pyrazole insecticide in the lignocellulosic composite material was determined against workers of the eastern subterranean termite, Reticuliterme flavipes . The control was an ordinary, untreated oriented strand board. Petri dishes were used as containers for termite assay. Each Petri dish was set up with a thin layer of moistened sand. Two corners (triangle with 15×15×20 mm) of a composite material were placed directly onto the sand. Thirty termites were placed into the dishes, the lid replaced, covered with blotter paper, and then held in an incubator (25° C.). Data was collected at specified days after treatment listed above recording knocked down, or dead termites, and intoxicated termites.
[0052] In Examples 1-4, the mean percent mortality of termites approached 100 percent, whereas the Control only reached a mean percent mortality of 3.3 percent. It is to be appreciated that these results were observed only over a short period of time, whereas in practice, the composite material will be exposed for longer period of times. Therefore, the results for the treated composite material will provide a greater insecticide resistance over time relative to the Control.
[0053] While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A lignocellulosic composite material and a method for preparing the lignocellulosic composite material are disclosed. The composite material is formed from lignocellulosic particles and a binder resin. The binder resin comprises a polyisocyanate, at least one of insecticide and/or fungicide that are dispersed throughout the polyisocyanate. The insecticide and/or fungicide is also dispersed throughout the lignocellulosic particles. Since the insecticide and/or fungicide is dispersed throughout the composite material, the composite material is insect resistant and is able to withstand insect attacks and prevent fungus growth and decay. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to a washing machine, and more particularly, to a centrifugal washing machine in which a detergent solution is passed through a laundry for washing the laundry.
2. Discussion of the Related Art
A washing machine strips contaminants from between fibers in general by applying energy such as impact and the like to the laundry. Depending on the type of energy applied to the laundry, there are pulsator washing machines, drum washing machines, agitator washing machines, and the like. That is, washing is done either by giving impacts to the laundry by means of the pulsator or a washing rod, or by the impact given to the laundry when the laundry tumbled, in addition to an action of the detergent added thereto. However, conventional washing machines have problems in that the laundry can be damaged from the impact or tangled during the rotation. Accordingly, in order to solve the aforementioned problems, research on washing laundries without rubbing or giving impacts to the laundries is underway, with fruitful results in which washing machines employing a low frequency wave, washing machines employing centrifugal force and the like are developed to a stage of commercial production.
The washing machine employing centrifugal force carries out washing by passing a detergent solution through fibers of the laundry under the following principle.
In principle, the action of washing is a stripping of contaminants from the laundry in the course of the detergent passing through the laundry. It is known from an experiment that the washing can be done when a flow speed of the detergent solution passing through the fibers of the laundry relative to the laundry is more than 1 m/s. Thus, when the detergent solution is passed through a laundry higher than a certain speed, the washing can be done even if the laundry is neither rubbed nor squeezed, namely, the principle employed in the centrifugal washing machine. One example of the centrifugal washing machine is disclosed in Korean Patent Laid Open No. 94-9417. This prior art centrifugal washing machine has problems in that it has great power, water and detergent consumptions because it requires both a high flow rate of detergent solution for spraying the detergent solution through detergent solution spraying holes formed all over a spray device provided on a central portion of a washing tub and a large sized pump for exerting a great spraying power required for the washing. And, this prior art centrifugal washing machine has problems in that it has a complicated construction because a difference of rotational speeds required for the washing tub and the spray device requires an additional device which can convert a rotational speed of a motor into two rotational speeds that are different from each other and transmit the rotational speeds to the washing tub and the spray device, respectively.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a centrifugal washing machine that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a centrifugal washing machine in which a small sized detergent solution spray pump can be used for reducing power, water and detergent consumptions.
Another object of the present invention is to provide a centrifugal washing machine which has a simple construction.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the centrifugal washing machine includes an outer tub supported in a body of the washing machine, an inner tub rotatably held in the outer tub, a spray device rotatably held at a center of the inner tub and having a detergent solution spray hole with a narrow width and a long length and an end bent to one side, a detergent solution supply tube connected between an under side of the outer tub and one end of the spray device for guiding a detergent solution filled in the outer tub to the spray device, a pump fitted in the detergent solution supply tube for pumping the detergent solution, a first valve and a second valve fitted at an inlet and an outlet of the detergent solution supply tube respectively for opening and closing the detergent solution supply tube selectively, and a foam eliminating means for eliminating foam produced as the detergent solution is circulated when the pump is operated.
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 illustrates a cross section of a centrifugal washing machine in accordance with a first embodiment of the present invention;
FIG. 2 illustrates a section across line I--I in FIG. 1;
FIG. 3 illustrates a cross section of a centrifugal washing machine in accordance with a second embodiment of the present invention;
FIG. 4A illustrates a longitudinal section of a spray device applied to the second embodiment of the present invention;
FIG. 4B illustrates a longitudinal section of another embodiment spray device applied to the second embodiment of the present invention; and,
FIG. 5 illustrates a cross section of a centrifugal washing machine in accordance with a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
First Embodiment
FIG. 1 illustrates a cross section of a centrifugal washing machine in accordance with a first embodiment of the present invention, and FIG. 2 illustrates a section across line I--I in FIG. 1.
Referring to FIGS. 1 and 2, the centrifugal washing machine in accordance with a first embodiment of the present invention includes an outer tub 2 supported in a body on top of which a door 33 is provided and an inner tub 4 having a perforation of holes 4a rotatably disposed inside of the outer tub 2. And, there is a spray device 9 having a detergent solution spraying hole 9a rotatably disposed on a central portion of the inner tub 4. On the other hand, there is a motor 3 for rotating the inner tub 4 and the spray device 9 and different pipe line for flow of detergent solution which is a detergent dissolved in water. There is an inner partition wall 16 disposed vertically in the inner tub 4 having a perforation of holes 16a for introducing laundries after dividing an amount of the laundry for the inner tub and inside of the partition wall 16. And, there is a foam catching means, i.e., an outer partition wall 14 provided outside of the inner tub 4. The outer partition wall 14 is formed to have a greater diameter as it moves upward, with a foam catching net 15 provided at an opened top thereof. The spray device 9 has an upper portion with a detergent solution spraying hole 9a and a lower end connected to a detergent solution supply tube 10 by means of rotatable joint 11. The detergent solution spraying hole 9a with a narrow width and a long length has an end bent to one side as shown in FIG. 2 with diverged top and bottom in upward and downward directions, respectively, for even spray of the detergent solution in the upward and downward directions, respectively. The different pipe lines for flow of water and detergent solution have the following system. There are a water supply tube 6 fitted with a water supply valve 5 on top of the body of the washing machine and a drain tube 8 fitted with a drain valve 7 on an underside of the outer tub 2 for discharging the detergent solution from the washing machine. There is the detergent solution supply tube 10 connected between the spray device 9 and an underside of the outer tub 2 for supplying the detergent solution. There is a pump 12 in the middle of the detergent solution supplying tube 10 with a first valve 17 and a second valve 18 disposed at an inlet/outlet of the detergent solution supply tube 10 for selectively opening and shutting of the detergent solution supply tube 10. There is a heater 13 provided at one end of the detergent solution supply tube 10, i.e., at the outlet thereof for heating the detergent solution. And, there is a dry cleaning liquid supply tube 19 with a dry cleaning storage tank 22 connected between the inlet to the pump 12 and the outer tub 2, with a third valve 20 and fourth valve 21 fitted at the inlet/outlet of the dry cleaning liquid supply tube 19. There is a supplementary drain tube 23 with a fifth valve 24 between the outlet of the pump 12 (that is, between the pump 12 and the second valve 18) and the drain tube 8. Opening and shutting of the valves are controlled by a controller (not shown) in the washing machine.
The operation and advantages of the aforementioned washing machine of the present invention will be explained.
Upon selection of a washing button after opening the door 33 and introducing the laundry and detergent into the inner tub 4, washing, rinsing and spin drying are automatically conducted in response to control signals from the controller (not shown).
First, a washing cycle in case of water cleaning will be explained.
Upon selection of wash initiating mode together with a water cleaning button, the water supply valve in the water supply tube 6 is opened to supply water into the inner tub 4 until the inner tub 4 is filled with water to a certain level when the detergent is dissolved in the water into the detergent solution. Upon completion of supplying the water, the motor 3 rotates the inner tub 4 so that the laundry in the inner tub 4 and the inner partition wall 16 is pressed against the walls of the inner tub 4 and the inner partition wall 16 and a portion of the detergent solution flows to the outer tub 2 through the perforations of holes 16a and 4a in the partition wall 16 and the inner tub 4. Under this condition, the pump 12 in the detergent solution supply tube 10 is driven and the first valve 17 and the second valve 18 are opened, to supply the detergent solution to the spray device 9 to spray the detergent solution to the laundry through the detergent solution spray hole 9a in the spray device 9, thereby performing the washing. Namely, the sprayed detergent solution strips off contaminants inserted between fibers of the laundry while passing through the fibers. On the other hand, the spray device 9, held to slide on the inner tub 4, rotates automatically by a reaction of the spray of the detergent solution from the detergent solution spray hole 9a in the spray device 9 while the inner tub 9 is rotated by the motor 3, resulting in the rotation speeds of the spray device 9 and the inner tub 4 differing so that the spraying of the detergent solution is not concentrated on a spot, but evenly distributed all over the laundry. The small section of the detergent solution spray hole 9a of the present invention can make a spray speed high, and the spray speed is made still higher by the centrifugal force coming from rotation of the spray device 9, that improves a washing effect, because the spray speed of the detergent solution is a tangential vector sum of the spray speed from the detergent solution spray hole 9a and the rotation speed of the spray device 9. As there is one detergent solution spray hole 9a in the present invention instead of the plurality of detergent solution spray holes in the prior art, an intended spray speed can be obtained by a low capacity pump. And, as the detergent solution spray hole 9a is formed diverged in the upward and downward directions, to diverge the spray in the upward and downward directions, the laundry at an upper portion and a lower portion in the inner tub 4 can be cleaned evenly. If a large amount of laundry is washed, it is possible that the detergent solution sprayed from the detergent solution spray hole 9a will be unable to pass through the laundry at an intended relative speed, or will be unable to pass through the laundry at all, in which case the laundry may be introduced into the two spaces formed by the inner tub 4 and the inner partition wall 16, dividing the laundry by a certain amount for obtaining the intended spray speed. The intended spray speed is attained the rotated inner tub 9 and the inner partition wall 16 lead the sprayed detergent solution to the inner partition wall 16 where the detergent solution is again sprayed through the perforation of holes 16a in the inner partition wall 16 by the centrifugal force at the moment it reaches to the inner partition wall 16. In the meantime, the detergent solution that has passed through the laundry runs out toward the outer partition 14 through the perforation of holes 4a in the inner tub 4, during which foam is formed. Though the detergent solution in the outer partition wall 14 overflows into the outer tub 2 by flowing over the outer partition wall 14 by the centrifugal force, most of the foam stays in a space between the inner tub 4 and the outer partition wall 14. The small amount of foam flowing toward the outer tub 2 together with the detergent solution is caught by the foam catching net 15, thereby the foam can not flow toward the outer tub 2, but stays between the inner tub 4 and the outer partition wall 14, eliminating the foam. Since heating the detergent solution supplied to the spray device 9 with the heater 13 at the outlet of the detergent solution supply tube 10 provides an effect of boiling the laundry, the effect of washing can be further improved.
A draining operation, discharging contaminated detergent solution to outside of the washing machine after the washing cycle, will be explained.
Upon completion of the washing cycle, the drain valve 7 is opened, draining the detergent solution out of the washing machine through the draining tube 8. In this instance, since the first valve 17 at the inlet to the detergent supply tube 10 is opened, the second valve 18 at the outlet from the detergent supply tube 10 is closed, and the pump 12 is put into operation, discharging the detergent solution out of the washing machine through the supplementary drain tube 23, the draining can be done quickly.
Upon completion of the draining operation, identical to the aforementioned washing cycle, the rinsing cycle is carried out, and upon completion of the washing cycle and the rinsing cycle, the spin dry cycle is started. In the spin dry cycle, the inner tub 4 is rotated at a high speed, extracting water contained in the laundry as the laundry is pushed onto a wall of the inner tub 4, thereby carrying out the spin drying. In this case, as the drain valve 7 is only opened when the pump 12 is stopped, the water is drained through the drain tube 8.
The case of dry cleaning without water will be explained.
After introducing laundry into the inner tub 4 and filling a dry cleaning liquid in the dry cleaning liquid storage tank 22, a wash initiating mode and a dry cleaning washing button are selected. Then, the second, third and fourth valves 18, 20 and 21 are opened and the pump 12 is put into operation, to spray the dry cleaning liquid stored in the dry cleaning liquid storage tank 22 through the detergent solution spray hole 9a in the spray device 9, thereby carrying out the washing. In this instance, water is not supplied as the water supply valve 5 is shut. Since other operations are identical to the water cleaning case, explanations of the operations will be omitted.
Second Embodiment
The second embodiment, being a modification from the first embodiment, is designed to wash laundries with different washing conditions separately.
FIG. 3 illustrates a cross section of a centrifugal washing machine in accordance with a second embodiment of the present invention, FIG. 4A illustrates a longitudinal section of a spray device 9 applied to the second embodiment of the present invention, and FIG. 4B illustrates a longitudinal section of another embodiment of spray device 9 applied to the second embodiment of the present invention, referring to which the second embodiment will be explained.
There is a divisional plate 34 detachably disposed horizontally in the inner tub 4, allowing to divide the inner tub 4 into two spaces (an upper space and a lower space). The spray device 9 is provided with a separation plate 35 for forming two detergent solution passages and two detergent solution spray holes 9a and 9b for spraying the detergent solution into the upper space and the lower space, separately. A first supplementary valve 36 and a second supplementary valve 37 are provided in the passages respectively to be controlled by the controller (not shown) for selective opening and shutting of the passages.
The operation and advantages of the second embodiment of the present invention will be explained.
In case it is desired that two sort of laundries, for example, a highly dirt laundry and a general laundry are washed separately, the laundries may be washed after introducing the laundries into the two spaces in the inner tub 4 divided by the divisional plate 34, separately. In this instance, the detergent solution is individually sprayed into respective spaces by means of the separation plate 35 provided in the spray device 9. If the laundry only exists in the lower space of the inner tub 4, only the first supplementary valve 36 is opened to spray the detergent solution only into the lower space, in which case a spraying power of the detergent solution becomes greater, which improves a washing effect. In this embodiment, the detergent solution spray holes 9a and 9b in the spray device 9 may be formed in the same direction as shown in FIG. 4A, or in directions opposite to each other as shown in FIG. 4B.
Third Embodiment
The third embodiment of the present invention has a foam catching means different from that of the first embodiment, but with the same basic washing principle as the first embodiment.
FIG. 5 illustrates a cross section of a centrifugal washing machine in accordance with a third embodiment of the present invention, referring to which the third embodiment of the present invention will be explained.
There is a water supply tube 6 to which a supplementary water supply tube 25 is connected. An outlet side of the supplementary water supply tube 25 has a form of a ring to form a ring tube 26 which is provided in the inner tub 4. The ring tube 26 has a plurality of holes 26a for spraying water into the outer tub 2. There is a detergent solution storage tank 29 in a middle of a drain tube 27, with a sixth valve 28 and a seventh valve 30 at an inlet/outlet of the detergent solution storage tank 29. There is a supplementary detergent solution supply tube 32 with a eighth valve 33 therein connected between the detergent solution storage tank 29 and the detergent solution supply tube 10. That is, the detergent solution having the foam eliminated therefrom stored in the detergent solution storage tank 29 can be used again by supplying it through the spray device 9. Though not explained, like the first embodiment of the present invention, elements required for carrying out the dry cleaning can be added to this third embodiment.
The operation and advantages of the third embodiment of the present invention will be explained.
As the sixth valve 28 is opened in the washing cycle, a portion of the detergent solution is stored in the detergent solution storage tank 29, and the foam produced as the detergent solution passes through the laundry is collected in the outer tub 2. In the washing cycle, there is a certain duration of pause, during which the foam in the outer tub 2 is eliminated. In detail, in the elimination of the foam, the sixth valve 28 is closed and the water supply valve 5 is opened, supplying external clean water through the water supply tube 6, a portion of which is guided to the supplementary water supply tube 25 and sprayed downwardly at a certain pressure through the holes 26a formed in the ring tube 26, that breaks the foam collected in the outer tub 2, eliminating the foam. Thereafter, when a washing cycle is started again, as the eighth valve 33 is opened and the pump 12 is put into operation, the detergent solution in the outer tub 2 and the detergent solution in the detergent solution storage tank 29 are supplied to the spray device 9 so that the detergent solution supplied to the spray device 9 is sprayed onto the laundry at a certain speed through the detergent solution spray hole 9a, thereby the washing is carried out.
It will be apparent to those skilled in the art that various modifications and variations can be made in the centrifugal washing machine of the present invention without departing from the spirit or scope of the invention. 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. | Centrifigal washing machine is disclosed, in which a small sized detergent solution spray pump can be used for reducing power, water and detergent consumptions, including an outer tub supported in a body of the washing machine, an inner tub rotatably held in the outer tub, a spray device rotatably held at a center of the inner tub and having a detergent solution spray hole with a narrow width and a long length and an end bent to one side, a detergent solution supply tube connected between an under side of the outer tub and one end of the spray device for guiding a detergent solution filled in the outer tub to the spray device, a pump fitted in the detergent solution supply tube for pumping the detergent solution, a first valve and a second valve fitted at an inlet and an outlet of the detergent solution supply tube respectively for opening and closing the detergent solution supply tube selectively, and a foam eliminating means for eliminating foam produced as the detergent solution is circulated when the pump is operated. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to coating plant seeds with a functional material which disintegrates after becoming wet to allow normal germination of the seeds.
2. Description of the Prior Art
It is known in the art to coat seeds with a functional material to provide protection against mechanical or environmental damage, and to use such coatings as a carrier for various materials such as, for example, fertilizer, pesticide, herbicide, etc. Such coatings have generally been of a water soluble material, so that the coating would dissolve to allow exposure of the seeds to the atmosphere for development. Such water soluble materials include water soluble polymers. Specifically U.S. Pat. No. 2,651,883 relates to use of polymeric water soluble polyelectrolytes as seed coatings. U.S. Pat. Nos. 3,707,807 and 3,598,565 relate to use of water soluble neutralized copolymer of an α,β-unsaturated monocarboylic acid and a lower alkyl acrylate and a crosslinked copolymer of vinyl acetate and a lower alkyl acrylate. In contrast, U.S. Pat. No. 3,316,676 relates to a water insoluble seed coating, the integrity of which is destroyed by shrinkage due to contact with water. U.S. Pat. No. 3,905,152 relates to seeds having a coating thereon comprising non-porous, hydrophobic, non-phytotoxic particles which are adhered to each other and to the seed by means of a hydrophilic binder in such a manner that the coating is highly porous and provides facile gas and water exchange between the seed and the environment.
SUMMARY OF THE INVENTION
According to this invention, compositions for coating plant seeds are provided comprising a water insoluble microgel. The microgel is functional in that is provides protection for the seeds from mechanical and environmental damages and may be used as a carrier for materials such as fertilizers, herbicide, pesticides, etc. An important feature, however, is the fact that the microgel does not dissolve when contacted with water. Instead, the outer layer of the microgel swells and falls away dissrupting the coating, and the swelling and falling away continues until the coating is removed. An advantage of such a coating is that there is no dissolved material available to fill the pores of the seeds to thereby retard germination. The coating quickly disintegrates upon contact with water for releasing any carried substances and expose the seeds to their natural environment.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings illustrate a preferred method and apparatus for coating seeds in accordance with this invention. In the drawings:
FIG. 1 is an elevation view in cross-section illustrating apparatus and showing gas flows and seed flow path from an annular bed through a truncated hollow cone and in return to the annular bed;
FIG. 2 is a partial elevation view in cross-section of a modified apparatus and illustrating the addition of an annular airfoil and showing the flow of gases relative to the aerodynamic structure and annular airfoil;
FIG. 3 is a partial elevation view in cross-section of another modified apparatus similar in all other respects to the modification shown in FIG. 2 except that the cross-section of the apparatus below the coating chamber is of the same diameter as that of the coating chamber;
FIG. 4 is partial elevation view in cross-section of the upper portion of the apparatus, illustrating one possible manner of collecting the seeds by use of an air porous bag; and
FIG. 5 is a graphic illustration of the height, thickness and angular relationships of the annular airfoil with respect to the aerodynamic structure, and the height above (h a ) and height below (h b ) relationships of the aerodynamic structure to the greatest cross-sectional diameter of the aerodynamic structure.
DETAILED DESCRIPTION OF THE INVENTION
According to the present invention, plant seeds (e.g., vegetable, crop, flower) are coated with a water-sensitive polymeric microgel such as that described in detail in U.S. Pat. No. 2,908,659. By a microgel is meant a unimolecular colloidal particle of a cross-linked polymer having on the average a diameter of from about 0.01 micron to no greater than about 3 microns cross linked to such an extent that it forms a "microsol," as defined hereinafter, when extended in liquids in which it is swellable, and exhibits therein a characteristic defined as a "gel point" which will be described in detail hereinafter. The transition from the soluble to the insoluble form proceeds gradually in a direct relation to the degree of cross-linking. As solubility decreases, characteristic swellability is observed. Swellability diminishes as cross-linking is increased. The art denotes the insoluble form as cross-linked. The recognition of the liquids in which a particular cross-linked polymer is swellable will be obvious to those skilled in the art. In general, where the product is formed from a linear polymer by cross-linking, it is swellable in those liquids in which such linear component exhibits solubility. Where no identifiable linear counterpart exists, swellability follows analogously the recognized laws applicable to the solubility of linear polymers.
The microgel particle is a cross-linked polymer, i.e., it is swellable in certain liquids, but does not dissolve therein in the accepted sense of the term. Because of its particle size limitations it possesses unique properties when extended in a medium in which it is swellable. When a microgel is distributed in an extending medium, the product will be referred to as a "microsol."
A microsol partakes of some of the properties of both true dispersions and true solutions. The particles exhibit Brownian motion. The microsols do not follow Staudinger's law, which relates viscosity to molecular weight. Microsol viscosities have been observed to have no relation whatever to the molecular weight of the microgel. On evaporation of the extending medium, the microgel particle, in its original discrete form, is recovered. The microsols possess a "gel-point", i.e., a concentration of a given microgel particle in a given extending medium at which the extending medium is absorbed by the microgel particles. Below the gel point the microgel particles have no appreciable effect upon the viscosity of the extending medium. At and above the gel point, a sharp increase in viscosity with increase in microgel concentration is observed. The gel point will vary for any particular system, but it can be readily determined empirically by plotting the percent concentration by weight of microgel against the viscosity of the microsol.
Among the useful water sensitive monomers for the production of microgels by addition polymerization include acrylic acid; methacrylic acid; hydroxy esters, amino substituted esters and amides of acrylic acid, methacrylic acid and maleic acid; vinylpyridine and derivatives of vinyl pyridine such as 2-methyl-5-vinylpyridine.
Also of value to the practice of the invention are polymers which are made to have the structure of a microgel by virtue of chemical reaction such as cross-linked polyvinyl acetate obtained as a latex wherein the latex is hydrolyzed by reaction of a strong base such as sodium hydroxide to obtain a gel comprised of cross-linked polyvinyl alcohol and cross-linked polyethyl acrylate latex reacted with strong base to obtain a polyacrylic acid sodium salt microgel.
Appropriate cross-linking agents are chosen in accordance with conventional practice in the production of cross-linked polymers. Compounds useful in this function include those which contain two or more times the vinyl or acrylic grouping, as for instance, divinyl benzene, diallyl cyanamide, ethylene diacrylate, methylene diacrylamide, ethylene glycol divinyl ether, triethylene, dimethacrylate, vinyl acrylate and glycerol trivinyl ether.
In addition to the emulsion technique, the cross-linking reaction may also be carried out by subjecting an emulsion of a solution of the linear polymer in the presence of a cross-linking agent to polymerization conditions. In such a process, the cross-linking agent may act as the solvent for the linear polymer, or the linear polymer may be dissolved together with the cross-linking agent in an inert solvent.
The appropriate catalyst, dispersing agent and dispersion medium for any particular microgel formation is chosen in accordance with conventional practice in addition polymerization by the dispersion technique. The dispersed phase must be maintained fine enough usually by a combination of dispersing agent, agitation, and reaction period, to maintain the average size of the formed microgel particle to less than 3 microns in diameter.
Microgels useful in accordance with the present invention may also be formed by condensation. In such processes they are preferably produced by a modified emulsion technique. In this process, each reactant is dissolved in a different solvent, the solvents being of such character they they are immiscible, i.e., one may be polar and the other nonpolar. The solvents must be liquid at reaction temperature. An emulsion of the incompatible solvents is formed, preferably in the presence of a dispersing agent. On addition of the continuous phase reactant (i.e., the reactant soluble in the continuous phase) and the discontinuous phase reactant to the emulsion of incompatible solvents (referred to hereinafter as a reactant contact medium), polymerization by condensation occurs at the emulsion interface. The product may thereafter form a microsol in one phase or the other at alternately being non-swellable in either phase, precipitate out or form a dispersion as a microgel. Where required, a cross-linking agent may be incorporated in either or both phases. A stabilizing agent is advantageously employed in either or both phases where formation of the polymer occurs as a minute dispersion and precipitation is not desired. A condensing agent to remove products formed during reaction may also be present to assist polymer formation.
It is preferred that the microgels have a gel point of from about 15 to about 35%. This corresponds to a swellability of 500 to 300%. The lower limit of cross-linking will vary widely in terms of gel point and swellability factor, depending on the nature of the particle. The extent of cross-linking can be controlled by conventional reaction modifications such as variation of the proportion of reactants, choice of catalyst, polymerization period, reaction temperature and the like.
The degree of crosslinking is sufficient to limit the degree of hydration but does not preclude the formation of films from suspensions of the solvated microgel. A microgel has sufficient crosslinkages between linear chains so that the solvated particle can only interact with other like particles by limited entanglement of molecular chain segments located at the periphery of the particles. A characteristics of such particles is that the particle can only absorb limited solvating substances before cohesive forces between particles are destroyed. It is this characteristic which is utilized in the practice of this invention. A seed coated with a soluble polymer germinates more slowly than an uncoated seed. Both the permeation and the removal of a soluble polymer require sufficient solvating liquid to mobilize outer layers of polymer as well as liquid to solvate remaining layers. It is well known that the water vapor permeability of a hydratable polymer is a direct function of hydration of the film. The amount of water necessary to both remove a water-soluble seed coating and provide water for the seed's germination processes is much greater than that for an uncoated seed.
The response of a crosslinked water-sensitive microgel to water is different than that of a soluble polymer. In the case of a film or coating composed of cohesively bonded microgels, the first action of the water is to swell the microgel particles to the solvation limits which are much less than for soluble polymers. These swollen microgels then tend to separate from the mass of the coating by ablative-like mechanisms, thereby rapidly exposing new regions of the film to the errosive effects of water. The film composed of microgels also tends to fracture as it is swollen by hydrating water to the extent that the film essentially loses all barrier properties. This fracturing exposes the seed to the water source and the natural swelling response of the seed further disrupts the film. The net effect of coating a seed with a film composed of cohesively bonded crosslinked microgels is that on contact with water, the total retardation of the natural response of a viable seed to water is so slight that it is not observable from natural variation in a lot of seeds. If the microgel is composed of a polymeric substance more hygroscopic than the layer on the seed known as the natural seed coat, the overall germination of the seed is accelerated when compared to an uncoated seed.
In the practice of the invention, a microgel derived from natural polymers or from synthetic polymers may be further modified or contain additives which render a film formed in contact with a viable seed hygroscopic. Inclusion and/or attachment of hygroscopic moieties such as glycerol, hygroscopic inorganic salts such as sodium sulphate are therefore useful in some instances.
A very important practice of the invention is the employment of the film composed of or containing significant proportion of microgels as a carrier for various agrichemicals of benefit to the life stored in a viable seed or to the emergent seedling or even to the resulting plant. The additive substances include fungicides and antibacterial agents to protect the seed during storage and fungicides and antibacterial agents to assist the seedling plant in combatting the soil borne pathogens. Also included are the use of plant hormones beneficial to the seed or seedlings as well as plant growth regulators. Many such substances are known to the art of agronomy and more are being identified.
The incorporation of such desirable substances may be by direct addition to the microgel as it is being used to coat the seed or they may be separately combined with small particulate articles of manufacture such as microcapsules containing a discrete wall and core, microencapsulated by inclusion in a finely divided polymeric matrix or microencapsulated by inclusion in the voids of an inorganic substance such as aggregates of clay or the lattice of an expandable mineral such as vermiculite.
The polymeric substances attached to or surrounding the seed may be composed of multiple layers of microgels of different composition or one or more different microgels in combination with one or more soluble polymers.
The polymeric substances comprise microgels and in some instances soluble polymers may be modified with pigments, fillers, and/or plasticizing substances as is well known to the art of compounding polymeric substances. The films can be formed on the surface of the seeds by spraying using atomized solutions of well known solvents for the particular polymer or melts, by contacting the seeds simultaneously with powders and solvents or adhesives, or by polymer forming techniques such as are well known to the pharmaceutical dosage forming art. Normally, the coating thickness will be between about 0.5 and 10 mils, or a coating weight of about 0.25-5%, based on the weight of the coated seed.
A preferred method and apparatus for coating the seeds is illustrated in the drawings.
The apparatus employs a truncated hollow cone in which the slope or pitch of the walls is such that the seeds are accelerated at an increasing rate and not just at a rate so as to maintain the gas velocity at any given point in the cone at a level greater than that necessary to move the particles in a continuous upward direction. The significance of the slope or pitch of the truncated hollow cone of the invention is that when a particles first enters the cone at one rate of speed, it is then accelerated to a different rate of speed and continues to be accelerated to still different rates of speed as it moves upwardly through the cone. In this manner a separation is brought about between the particles so that after they are coated they may become sufficiently dry before coming into contact with other particles and thereby avoid undesirable clumping or agglomerating together. The pitch of slope is such as to cause a compression of the gas molecules and thereby cause the acceleration at an increasing rate.
In reference to FIG. 1, the coating apparatus is designated in general at 10 and includes a vertically disposed first hollow column 12 of regular shape. By "regular shape" is meant that it may be cylindrical, octagonal, hexagonal or of other configurations, so long as the hollow column is generally symmetrical with respect to its central axis. The hollow column contains therewithin the particle storage, coating, drying and deceleration zones, which will be described herein.
A truncated hollow cone 14, which may also be a tapered octagon or other tapered polygonal configuration, in other words, generally cone-shaped configurations, serving as an enclosure in which the upwardly flowing gases are received, compressed and accelerated, is centrally disposed within the first hollow column, has a uniformly decreasing cross-section in the upward direction and is of predetermined height dependent upon the size and weight of the seeds to be treated. Within the truncated hollow cone in ascending order are the coating and drying zones. The cone serves also to separate the coating and drying zones from the deceleration zone, which lies in the region above the upper end of the cone, and from the storage zone, which lies therebetween the cone and the interior wall surface of the first hollow column.
The first hollow column 12 is provided at its lower end with an inwardly tapered base 16. The lower end of the truncated hollow cone is spaced radially inwardly from the inwardly tapered base.
A second vertically disposed hollow column 18 of regular shape is connected to the inwardly tapered base of the lower end of the first hollow column, the wall surface of the inwardly tapered base forms a juncture with the wall surface of the second hollow column.
Disposed within the second hollow column is a first plenum chamber 20 into which a suitable compressed gas, such as air, may be provided through two or more opposed inlets 22, 24; a gas or air collimating plate 26; a second plenum chamber 28 separated from the first plenum chamber 20 by the collimating plate 26; at least one gas shaping or aerodynamic structure 30 disposed within the second plenum chamber; and a seed support or supporting screen 32, which extends across the second hollow column and is located above the aerodynamic structure.
The gas or air collimating plate 26 is a perforated plate which causes the gas or air in the first plenum chamber to pass into the second plenum chamber in an essentially vertical and uniform flow, as illustrated by the vertical arrows.
The gas shaping or aerodynamic structure 30 in cooperation with the adjacent wall surface of the second hollow column, compresses and focuses the upwardly moving gas or air flow so that it flows over a portion of the surface of the aerodynamic structure, upwardly through the particle support screen and into the entrance end of the truncated hollow cone. The flow upwardly around the aerodynamic structure constitutes an annular flow, which adheres to the surface of the aerodynamic structure in the nature of a Coanda flow.
A spray nozzle 34 preferably extends above the top of the aerodynamic structure 30 through which is sprayed a suitable coating material. It is more convenient to have the spray nozzle located at the top of the centrally disposed aerodynamic structure. The coating material is supplied from a suitable source (not shown) through a conduit 36 extending up through the aerodynamic structure, and an atomizing gas may be supplied from a suitable source (not shown) through a conduit 38, also extending up through the aerodynamic structure, for subsequent mixing at the nozzle. The spray nozzle may also be pressure-operated rather than gas-operated.
The upper surface of the gas shaping or aerodynamic structure is centrally disposed within and extends generally horizontally across the cross-section of the vertically disposed hollow column. In other words, it has a cross-sectional plane generally perpendicular to the vertical axis of the vertically disposed hollow columns. The outer edge of the upper surface is equally spaced from the wall surface of the hollow column and defines therebetween with the wall surface of the hollow column a reduced pressure region for acceleration in velocity of the upwardly flowing gases in such manner that the upwardly flowing gases form a boundary layer that is directed away from the wall surface of the hollow column and that adheres to the upper surface of the gas shaping or aerodynamic structure for flow across a portion thereof.
The upper surface of the aerodynamic structure may be flat (not illustrated), but is preferably curved or approximately spherical as illustrated. It may have a height (h a ) above the cross-sectional plane (See FIG. 5), therefore, of from about 0% to about 150%, or preferably from about 10% to about 150% of the greatest cross-sectional diameter (D) (See FIG. 5) of the aerodynamic structure.
The surface below the greatest cross-sectional diameter may also be flat (not illustrated) and may therefore have a depth or height (h b ) below of from about 0% to about 200% of the greatest cross-sectional diameter (D) (See FIG. 5). Preferably, the surface below is formed in the manner disclosed in the drawings.
The aerodynamic structure as disclosed and as described is thus adapted to compress and accelerate the flowing gases near the periphery of the hollow column and direct them toward the center of the hollow column at an angle from about 10° to about 45° from a direction parallel to the flowing gases from the gas or air plenums.
The truncated hollow cone defines at its lower end a large diameter somewhat similar than the diameter of the vertically disposed first hollow column, and has an increased diameter from about 0% to about 25% greater than that of the plane of the particle support screen. The lower end of the truncated hollow cone is spaced a predetermined amount from the screen and the upper end defines a diameter of from about 20% to about 80% of that of the lower end. The height of the cone ranges from about one to about six times the diameter of the lower end.
In operation, seeds 40 may be suitably loaded into the coating apparatus 10, as through a closable opening at 42, into the storage zone lying between the wall surface of the first hollow column 12 and the outside wall surface of the truncated hollow cone 14. The seeds are thus situated in an annular bed around the truncated hollow cone 14. The sloping outer wall surface of the truncated hollow cone, the inwardly sloping tapered base 16 of the first hollow column and the screen 32 serve to contain the particles in the annular bed prior to starting-up the coating operation.
The gas or air is turned on to start the circulation of the seeds from the annular bed or storage zone into the coating, drying and deceleration zones and in return to the upper portion of the annular bed. The atmoizing spray is then turned on and appropriately adjusted in a suitable manner by controls (not shown).
As previously pointed out, the Coanda flow or effect is named for the tendency of a fluid, either gaseous or liquid, to cling to a surface that is near an orifice from which the fluid emerges. Such "orifice" in this instance is formed in the region therebetween the closest approach of the aerodynamic structure to the adjacent side wall surface. The gas flow emerging from the "orifice" region around the aerodynamic structure is an annular flow which clings or adheres to the surface of the aerodynamic structure. The flow, therefore, from any one selected location around the "orifice" is opposed by the other flows so that it is prevented from continuing further over the upper surface of the aerodynamic structure by being forced upwardly away from the upper surface at some point for flow into the truncated hollow cone. A partial vacuum is formed in the region just above the upper surface of the aerodynamic structure and at the lower edge of the truncated hollow cone and this aids in the compression and focusing of the rising annular flow of gases. The upward flow is consequently caused to have a conical shape, as seen in phantom lines in FIG. 1 at 44 within the cone, and has a centering effect on the particle impelled upwardly through the cone.
As also pointed out, an important part of the Coanda effect is the tendency of the flow or gas or liquid to entrain, or draw in, more gas or liquid from the surrounding environment. In this latter manner, the particles are pulled from the annular bed or storage zone into the upwardly flowing gas due to the aforementioned partial vacuum or reduced pressure region that exists just above the screen adjacent the path of upward flow as a consequence of this Coanda effect. This reduced pressure or partial vacuum is directed perpendicular to the annular airflow from the "orifice". It is a different effect, however, from the horizontal shunting action occurring in the Wurster et al apparatus described above because there the horizontal shunting would extend not only toward the axis of the apparatus but also inefficiently toward the outer wall surface of the coating apparatus.
Once the seeds are pulled into the upwardly flowing gas within the truncated hollow cone, they are impelled upwardly in an accelerating gas or air stream. As the seeds pass through the lower central region or coating zone within the cone, they are contacted with an atomized spray coating of material. This atomized spray emerges from the spray nozzle 34 because the liquid coating substance is either forced through a single orifice designed to convert bulk liquids into droplets, or the liquid and an atomizing air stream emerge simultaneously from jets adjacent to each other. In either case, the fine droplets of coating material are in a flowable state, because the material is dissolved or melted in the region immediately above the spray nozzle.
Further up the truncated hollow cone, the liquid nature of the coating material, as deposited on the seeds, changes to solid by evaporative or other solidification processes. During the transition from liquid to solid, the seeds pass through a stage when they are sticky or tacky and would agglomerate if they contacted each other. This contact is prevented by the slope or pitch of the walls of the truncated hollow cone and consequent accelerating boost of the seeds to separate them in the manner previously discussed.
The conical nature of the cone causes a compression and acceleration of the rising column of gases and the upward velocity or acceleration of the particles occurs at an increasing rate as they rise in the cone. This acceleration causes an increasing vertical separation in space between the seeds and therefore reduces the tendency for the particles to contact each other until the coating has become nontacky. It is this region of the cone that is thus called the "drying zone".
When the compressed gases and entrained seeds pass upwardly out of the upper end of the cone, they expand into the larger area of the upper portion of the first hollow column and thus decelerate to a velocity too low to suspend the seeds. This is the deceleration zone, where further drying takes place, and the seeds then fall by gravity action to the annular bed where they gradually move down, also due to gravity, until they are pulled into the coating zone again. This recycling or recirculation continues until, based on previous experiments, a sufficient coating has been applied.
The atomized spray is turned off, and the gas or air entraining flow may be shut down or may be increased to drive the coated seeds into the uppermost region of the first hollow column, as for collection in the manner illustrated in FIG. 4. Any other suitable manner of unloading the finally coated particles may also be used.
A coating apparatus having the design characteristics essentially as shown in FIG. 1, and having a diameter of eight (8) inches across the lower end and four (4) inches across the upper end of the truncated hollow cone, is charged with twenty-five (25) pounds of cotton seeds. About 250 standard cubic feed per minute of air at about 7 p.s.i.g. is admitted to the plenum chamber 20. This air causes a circulation of pellets through the truncated hollow cone 14, and the height of the cone above the support screen 32 is adjusted to obtain a pellet flow rate such that all the pellets in the annular storage zone move through the cone about once every minute. A coating latex is pumped through the sprya nozzle 34 at the same time as 5 SCFM of atomizing air at 40 p.s.i.g. is supplied to the nozzle. The pumping rate is adjusted to pump one (1) pound of solution per minute. The apparatus is operated for about 45 minutes. The product is a pellet core coated with about a 2-mil layer of the polymer.
If the gases flowing upwardly around the aerodynamic structure could be seen as a series of layers of molecules, merely for sake of discussion, it is thought that there is an insignificant flow of molecules or layer or so of molecules along the interior wall surface of the second hollow column. By "insignificant" is meant that such layer or layers of molecules will not perform any supporting function of the particles in the annular bed.
Moving, therefore, radially inwardly from the interior wall surface of the second hollow, the more significant layers of molecules are caused to bend toward the gas shaping or aerodynamic structure, the innermost adhering to the surface of that structure as they pass upwardly through the "orifice" region. This adherence of the molecules to the surface of the aerodynamic structure may be favorably compared to the "teapot effect", which is a low-speed form of the "Coanda effect". When water is poured slowly from a glass, it tends to stick to the side of the glass in the same way that tea sticks to the spout of a teapot. High speed fluids behave similarly and adhere to a surface of suitable shape.
As the rising molecules flow over the surface of the aerodynamic structure after having passed the "orifice" region, previously mentioned, at some point along the upper surface of the aerodynamic structure the opposing character of the annular flow forces the molecules upwardly away from the upper surface as well as the adjacent molecule layers. A partial vacuum is created above the aerodynamic structure due to the high speed upward flow of gases, causing an inward bending of the upwardly moving molecules.
In the apparatus herein described, the seeds move down in the annular bed by gravity without any "dancing" occurring, and are drawn into the upwardly flowing gases by the partial vacuum. Thus, any attrition that might occur is greatly minimized, and the overall operation is much more efficient.
In reference to FIG. 2 in which a modification is disclosed, the same reference numbers will be used to identify similar elements previously described, except that they will be primed to show that it is a different embodiment under discussion.
FIG. 2 represents an embodiment wherein the size of the coating apparatus 10' has been increased in order to handle larger batch loads of seeds for coating treatment. It has been found that it is more practical to add an additional gas shaping or aerodynamic structure or an annular airfoil 50 instead of increasing the size of the aerodynamic structure 30'. In this manner, larger amounts of upwardly flowing gas or air may be supplied undiminished or unobstructed by a larger aerodynamic structure, and the annular airfoil serves to supplement the compression and focusing action on the upward gas flows so that substantially all gas flows move through the truncated hollow cone 14'.
Additional or multiple gas shaping or annular airfoils (not shown) also may be used for still larger coating apparatus. The exact shape and placement of the airfoils are functions of a number of variables. The most significant of the variables are size of the apparatus, size of the seeds to be coated, density of the seeds, rate of gas or air flow and the rate of recirculation of the seeds through the coating zone desired.
In a larger-scale coating apparatus, therefore, one or more annularly shaped and placed gas shaping or aerodynamic structures or airfoils, angled or curved, may be provided concentric with and radially outwardly of the central gas shaping or aerodynamic structure. The annular airfoils may be attached to the central aerodynamic structure or to the walls of the coating apparatus by radial struts in such manner as to exert a minimum deflection of the upwardly flowing gases.
The annular aerodynamic structure is inwardly inclined in the upward direction so that its inclination lies in a plane extending about 10° to about 45°, as measured from the axis perpendicular to the diameter of the coating apparatus. The inwardly inclined annular structure provides a surface on which the gas or air impinges for subsequent shaping and direction upwardly into the truncated hollow cone.
The vertical height of the annular structure may be about 10-50% of the perpendicular cross section diameter of the coating apparatus.
In the reference to FIG. 5, when the annular gas shaping structure has the configuration of an airfoil having at least one curved surface extending generally in the direction of gas flow, the overall angle of a line described from a point p 1 , on the lower rim of the airfoil to a point p 2 , on the upper rim in the vertical direction, or perpendicular to a line which is tangent to the upper curved surface of the centrally disposed aerodynamic structure, is from about 10° to about 45° inward facing, as measured from the axis perpendicular to the diameter of the coating apparatus.
The cross-sectional configuration of an annular airfoil in a plane described from the center of the crosssectional area of the coating apparatus to a point, p 1 , on the lower rim of the airfoil to a point, p 2 , in the upper rim of the airfoil is teardrop, or similar to the crosssectional shape of a lifting aerodynamic shape, and having the thicker cross section on the forward part with reference to the direction facing the upwardly flowing gases. The thickest part is located about two-fifths (2/5) to about one-half (1/2) of the height in the vertical direction. In other words, the height (H) of the thickest part (T), or HT is equal to about 2/5 H to about 1/2 H. The thickest cross section (T) is from about one-sixth (1/6) to about two-fifths (2/5) of the height (H) of the airfoil; or T is equal to about 1/6 H to about 2/5 H.
The size, placement and geometrical configuration of the annular gas shaping structure are such, therefore, that the upwardly flowing gases are deflected radially inwardly at an angle from about 10° to about 45° from a direction parallel to the original gas flow.
In reference to FIG. 3, the same reference numbers will be used to identify similar elements previously described, except that they will be double-primed to show that it is still another different embodiment under discussion.
FIG. 3 represents an embodiment wherein the size of the coating apparatus 10" has been increased to the same extent as that disclosed in the FIG. 2 embodiment. The embodiment in FIG. 3 differs from the embodiment in FIG. 2 in that the first and second hollow columns are disclosed as being co-extensive in cross-sectional diameter. In other words, the coating apparatus is disposed within a single hollow column. It could also be of smaller size so that only one gas shaping or aerodynamic structure 30" is employed as in FIG. 1, instead of a size requiring the annular airfoil 50".
The recycling or recirculation in this embodiment is necessarily faster because the seeds are not as readily restrained in the annular bed region as they would be if there were an inwardly tapered base to assist in such restraint. Proportionately smaller batch loads may be used, therefore, since the recirculation of the seeds is substantially continuous with the particles spending very little time in the annular bed. For this reason, an embodiment of this character is suitable for special purposes, while the embodiments of FIG. 1 and FIG. 2 are deemed to be of more general use.
In FIG. 4 this embodiment represents one manner of unloading a coating apparatus, and was briefly mentioned above with respect to one possible operation of the embodiment of FIG. 1.
Only the upper portion of a coating apparatus 60 is shown, and it could be used for any of the previously described embodiments. A conduit 62 is installed within the upper portion of the apparatus, as shown, and a gas or air porous collection bag 64 may be installed at the remote end of the conduit for collecting the finally coated seeds in the manner already heretofore described.
In any of the embodiments described above, the truncated hollow cones may be adapted to be adjusted for movement upwardly or downwardly in a vertical plane. The same may also be accomplished with the aerodynamic structure, the annular airfoils and the spray nozzles, as desired to suit gas or air flows, seed sizes and weights, coating material consistencies and whatever other controlling factors may be concerned.
The seeds to be coated may be batch-loaded and treated; or, if deemed advantageous, two or more such coating apparatus may be arranged in cascaded manner to provide for a continuous coating operation. The inlet for the seeds in a cascaded arrangement may be disposed above the annular storage of one apparatus and the particles metered in predetermined manner into the annular storage bed, while the outlet to the next coating apparatus may be disposed on the opposite side of the annular storage bed and constitute a weir for outflow of excess coated particles. The inlet may also be disposed for gravity flow of seeds to or into the annular storage bed. It may be desirable to provide for different coatings in different apparatus, or provide supplemental coatings.
Multiple spray nozzles may also be employed, as desired, to achieve different coating effects.
The following examples are submitted for a better undrstanding of the invention.
EXAMPLE 1
A polymeric microgel is formed by high shear stirring the following mixture at 60° C.:
70 g acrylic acid
20 g styrene
10 g divinylbenzene
1000 g water
2 g Dupanol ME (sodium lauryl sulphate)
1 g Emulphor ON-870 (polyethylene oxide surfactant manufactured by GAF)
2 g potassium persulfate
The crosslinked polymeric dispersion obtained may be used as prepared or alternatively it may be dried by any of a variety of techniques. In this example, the polymer dispersion is evaporated to dryness and is then resuspended in acetone. Soybean seeds are coated by spraying the acetone containing 5-25% solids onto the surface of the soybeans. A continuous layer 0.001-inch thick of the polymer is obtained.
For the purposes of comparison, another lot of soybean seeds are coated with polyacrylic acid (0.5 intrinsic viscosity) dissolved in acetone. The seeds having both coatings are placed in test tubes on top of water-moistened plugs of cotton.
The seeds coated with the crosslinked polymeric microgel are observed to start water imbibition within five minutes. Within 10 minutes, the polymeric layer has formed numerous cracks due to swelling stresses imposed on the crosslinked structure. Within 30 minutes, the seed is observed to be swelling. The germination of the soybeans proceeds uninhibited by the crosslinked microgel.
The soybeans coated with the uncrosslinked polyacrylic acid show the first evidence of swelling only after about one hour and the polymeric film is still intact and remains intact until the radical of the seed thrusts the coating aside.
After five days, the seeds coated with the crosslinked microgel are fully germinated and about six inches tall whereas the seeds coated with the soluble polymer are only partially germinated and less than three inches tall.
EXAMPLE 2
The microgel composition described in Example 1 is suspended in acetone and, based on the weight of microgel, 0.05% of Captan 50% wettable powder fungicide is added. This mixture is used to coat soybean seeds which are contaminated with fungi in the dormant spore state. The seeds are germinated and are compared to untreated seeds. The coated seeds show no evidence of fungal growth whereas the uncoated seeds show some evidence of contamination on every seed. About 50% of the uncoated seeds show reduced degrees of germination due to infection by the fungi.
EXAMPLE 3
The process described in Example 1 is used to make a microgel from
70 g methacrylic acid
20 g styrene
10 g divinylbenzene
While still suspended as a latex in the polymerization mixture 30% of the carboxyl groups is neutralized with 10% ammonium-hydroxide solution.
EXAMPLE 4
A 50% portion of the microgel obtained in Example 3 is dried by evaporation of the water then, was resuspended in solvent composed of 30% water and 70% methanol having 10% microgel solids. This suspension is used to coat soybean seeds with a layer 3 mils thick. When the coated seeds are planted and compared to uncoated seeds similarly planted it is found that the rate of germination is essentially the same for both lots of seeds. After about 10 days, however, the coated seeds show an acceleration of growth due to the slow release of ammonia. Whereas for many crops the amount of ammonia provided by the described amount is insignificant, the soybean benefits because nitrogen fertilizer is not generally used since the plant is leguminous. The quantity of ammonia described is important to the new seedling before modulation of the legumious plant by nitrogen fixing bateria.
EXAMPLE 5
The second portion of the microgel obtained in Example 3 is admixed with 50 g. Captan 7% wettable powder. Next 100 g of methanol is added. This mixture is sprayed on 5000 g of sorghum seeds by the technique described in Example 1 until the seeds have 4% coating based on the seed weight. The seeds all germinate in soil infested by fungi and maintained at 21° C. Under these conditions the disease fungi are more favored than the seed but the seeds germinate in about 10 days whereas control seeds are essentially destroyed by fungi in the same period.
EXAMPLE 6
A microgel is made by first polymerizing vinyl acetate in the following process. The following mixture is stirred at 60° C. under a nitrogen blanket.
100 g vinyl acetate
2 g ethylene diacrylate
2 g sodium lauryl sulfate
1000 g water
1 g potassium persulfate
0.5 g sodium metabisulfate
After 4 hours a cross-linked latex of polyvinyl acetate is obtained. This latex is heated to the boil and 30 g sodium hydroxide is slowly added as a 40% solution in water. After 10 hours the result is a water swollen microgel of cross-linked polyvinyl alcohol partially precipitated by the presence of the sodium acetate obtained as a by-product. The solution is cooled and the microgel separated as a sludge from which the salt solution can be decanted. If further purification is required the volume of the sludge can be reduced by addition of methanol equal to 50% of the total volume, then the liquid can be decanted to provide essentially pure microgel. The microgel sludge is resuspended by adding at least 300 g water. If diluted with 500 g water it consists of about 33% suspension of microgel in water and useful as a seed coating to be applied by air suspension coating or by tumbler methods similar to tablet coating as is practiced in the pharmaceutical industry. The advantage of the seed coated with this formulation is to protect the seed from pathogen attack by sealing the seed from invasion by fungi spores or baterial pathogens during seed storage. This coating also functions as a soil conditioner after falling off during germination of the coated seed.
EXAMPLE 7
The microgel described in Example 6 as a 33% solids suspension in water is compounded with 0.1% hydroquinone based on the dry solids of microgel. This mixture is then coated on the coated seeds obtained in Example 6 to give a coated seed with two layers. These two layers serve to restrict the permeation of oxygen through the coating due to the low permeation rate of oxygen through polyvinyl alcohol. The traces of oxygen which do penetrate the polymer are reduced by the hydroquinone. Now the seed is protected from invasion by pathogens and protected against oxidative degradation during the storage period.
EXAMPLE 8
A microgel is made by the following process. First, 100 g of 2-methyl-5-vinylpyridine, 2.5 g dimethylbenzene, 900 g of water, 4 g of sodium stearate are stirred at 60° C. under a nitrogen blanket. Next, 1.5 g potassium persulfate is added and stirring is continued until polymerization of the monomers is complete, usually about 4 hours. The resulting polymer is obtained as a latex comprised of cross-linked spherical particles having an average diameter of about 1.0 microns. Next the water is removed by coagulating the latex, filtering and drying or by spray drying or other methods well known to the art of polymer technology. The product obtained is a dry powder of cross-linked polymer which, although is insoluble, can be suspended in organic liquids capable of either extensive swelling or dissolving linear uncross-linked poly-2-methyl-5-vinylpyridine. In this example the polymer is suspended in methanol to obtain a liquid containing 10% solids. Next, based on the total titratable basic amine functionality a stiochimetric quantity of dilute nitric acid is added. Soybean seeds are coated with this suspension of nitrate salt of microgel to form continuous layers of about 1 mil on each seed using an air suspension coater. The seeds are germinated in soil at a temperature of 21° C. These conditions provide both water stress and temperature stress for soybean seeds. However, since the coating is hydroscopic, sufficient water is collected and held on the surface of the seed to enable germination. In addition the nitrate ion is a nutrient for plants and a promotor of early germination.
EXAMPLE 9
Soybean seeds are coated in an air suspension coater with a layer of Ethacel (cellulose ethel ether) from a solution in methanol. A layer about 0.25 mil thick is developed on each seed. Next the seeds are coated with the microgel described in Example 8 in the same manner as described. These seeds are protected from a slight burning on seedlings of Example 8 by the barrier properties of the inner Ethocel layer.
EXAMPLE 10
Soybean seeds are coated in an air suspension coater with an acetone solution containing 5% by weight of polymethyl methacrylate and 12% by weight of finely divided calcium carbonate. This coating is deposited in a continuous layer about 0.75 mils thick and comprises a microporous structure permeable to gases and water. Next a 3 mil layer of the microgel described in Example 9 is applied by the air suspension coater. Over the microgel layer is applied yet another 0.75 mil layer of the polymethyl methacrylate containing calcium carbonate. The final coated seed now is covered with three layers. The function of the outermost layer is to adjust the planted pH providing a slight basic pH to the soil environment and acting as a deterrent to fungal attack of the seed. The second layer provides the nitrate ion for promoting early germination of the seed and early nutrition of the seedling plant. The innermost layer is a buffer or barrier preventing direct contact of the nitrate of the microgel layer with the seed surface. When the seeds are planted germination is rapid and seedling growth is accelerated. This multilayered coating is particularly beneficial to seeds which have deteriorated due to age. A lot of seeds over a year old and having germination rate of less than 50% emergence in typical soil are compared to the same seed having the described multilayer coating. The coated seeds germinate at the rate of 69% and the seedlings have improved vigor.
Unless otherwise specified, all parts, percentages, ratios, etc., are by weight.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. | Compositions are disclosed comprising a water insoluble microgel which when used as a coating for seeds provides protection for the seeds and may be used as a carrier for materials such as fertilizers, herbicides, pesticides, etc. The microgel does not dissolve when contacted with water, but the outer layer of the microgel swells and falls away, thereby dissrupting the coating, and continues until the coating is removed. An advantage of such a coating is that there is no dissolved material available to fill the pores of the seeds to thereby retard germination. The coating quickly disintegrates upon contact with water for releasing any carried substances and exposing the seeds to their natural environment. | 0 |
FIELD
[0001] Disclosed is a separation device for purposes of separating one constituent of a fluid, with a container,
an inlet and at least one outlet, wherein the inlet is arranged above the outlet, a filter material that has the ability to bind the constituent, for example oil, and is arranged within the container between the inlet and the outlet such that the flow is through the filter material.
BACKGROUND
[0005] Devices for the separation of fluids, or segregation devices for the segregation of fluids, are of known art. For example the registered design DE 90 040 19.8 describes a device for sucking out a light fluid that has been separated in a fluid separator. The said device has a housing in which a container is arranged in turn. In the container is located a bag, which is filled with an oil binding agent. The oil-binding agent is a buoyant granulate based on a polyurethane foam. The wastewater contaminated with a light fluid enters into the housing through the entry opening. As long as the oil-binding agent in the container is substantially unsaturated, the container is only slightly immersed into the layer of light fluid. The light fluid permeates into the container, and the bag containing the oil-binding agent, and is adsorbed by the oil-binding agent. With increasing saturation of the oil-binding agent the weight of the bag increases such that the container sinks ever further. When the container has reached its lowest position the oil-binding agent is substantially saturated with the light substance and the bag can be replaced. The fluid that is not absorbed exits through an outlet opening. Basically the principle of the said device is sensible, but the device itself is very complex and susceptible to faults. For example there is no guarantee that the total volumetric flow of the fluid mixture actually flows through the bag. In this respect complete filtering is not necessarily ensured.
[0006] Building on the said device, DE 600 04 523 D2 also describes a segregation device and a segregation method for the segregation of fluids with different densities. Fundamentally the device described in the above document functions in accordance with the same principle, namely that an adsorbent material is saturated with one of the two fluids and as a result sinks down into the other fluid. However, an essential difference consists in the fact that in the said device the total volumetric flow must pass through the segregating component, which consists of an adsorbing material. The segregating component is arranged within a container such that it completely fills the cross-section of the container. What is disadvantageous in the said device, however, is the friction between the segregating component and the container. With increasing adsorption, i.e. contamination, of the segregating component the frictional characteristics alter as a result of fluctuations in temperature and pressure, which in turn affects the filtering process and the necessary energy expenditure. As a result the device is susceptible to faults and this can lead to increased maintenance activity.
[0007] The separation devices, i.e. oil/water separators, have moreover the disadvantage that the discharge times before a changeover of the absorbing material are very long, and the absorbing material, i.e. the filter that has the said material, has a considerable weight in the case of the larger devices.
SUMMARY
[0008] Against this background creating a separation device that enables a simple and quick replacement of the filter material is disclosed. In particular the flow through the filter material should thereby be uniform. A further advantage consists in configuring the separation device such that it can be adapted to different spatial conditions. Adaptation with regard to volumetric flow rates, and/or with regard to the quantity of fluid to be separated should also be possible.
[0009] The advantage is achieved by means of a separation device with the features of Claim 1 . Accordingly the filter material is arranged in a cartridge that is inserted into the container.
[0010] By virtue of the arrangement of the filter material in a cartridge a better through flow and/or a simplification of the replacement of the filter material is enabled.
[0011] Regarding details of the filter material reference is made to the application DE 102005012718, which is hereby incorporated by virtue of the said reference. It is, for example, manufactured from polypropylene. It is, for example, a porous or a fibrous material.
[0012] The cartridge is, for example, closed, apart from an intake opening and an outlet opening that is connected with the outlet of the container in terms of fluid flow, and is manufactured out of plastic.
[0013] The cartridge is advantageously embodied in the form of a segment. This means that a plurality of cartridges, or cartridge segments, can be inserted into a container. The volume that is otherwise available for only one cartridge is therefore utilised by a plurality of smaller individual cartridges. Here the cartridges can be arranged next to one another, or one above another; what is important is that the space available must be utilised as effectively as possible. For example, in the case of a container with a rectangular cross-section each of the cartridges can have triangular cross-sections, such that four cartridges arranged adjacent to one another optimally fill the rectangular cross-section of the container. Alternatively and/or additionally horizontal partitioning can preferably be provided, in which the cartridges are arranged stacked one above another.
[0014] In what follows the term “cartridge” is used both for cartridges and also for cartridge segments.
[0015] The individual cartridges can have their own inlets in each case, through which the fluid, i.e. the fluid mixture, flows into the cartridges; in a particularly advantageous variant the individual cartridges are together immersed into the fluid level of the container. This has the advantage that the fluid can be optimally apportioned to all the cartridges. This leads to a better segregation result and, by virtue of the uniform utilisation of the individual cartridges, the achievement that the filter material within the cartridges is saturated at approximately the same point in time, so that all the cartridges can be changed over in only a single replacement procedure.
[0016] The individual cartridges can also be connected with one another such that the fluid, or condensate, flows firstly into a first cartridge and from there, through an outlet of the first cartridge and a corresponding inlet of a second cartridge, into the second cartridge.
[0017] Cartridges arranged one above another or in series can preferably be connected with one another by means of a central pipe, or riser. The riser preferably extends coaxially through the individual cartridges, and has openings through which the fluid that has flowed through the cartridges, i.e. through the filter material located within the cartridges, can flow into the interior of the riser. The said embodiment presents itself in particular in the case of an arrangement of the cartridges one above another. Thus the cartridges surround the riser in certain regions, wherein the fluid, or condensate, can flow in from above, from below, or radially, through corresponding openings in the cartridge walls into the cartridges. In this manner the cartridges are located totally within the fluid that is located in the container.
[0018] In a particularly advantageous variant of embodiment a plurality of cartridges can be arranged one above another and also next to one another. Within the container there are, so to speak, a plurality of towers, each consisting of a plurality of cartridges that are arranged next to one another.
[0019] Within the container the cartridges can be connected with one another, but they can also be held within the container fully independently of one another. In the above-described variant of embodiment, which uses a riser that passes through a plurality of cartridges, each of the cartridges can be attached to the riser, but they can also be connected with one another. It is essential that the cartridges are prevented from floating upwards. This can only be achieved by the connection of the cartridges with the riser.
[0020] In a particularly advantageous variant of embodiment the cartridges have central openings in which a cartridge sealing ring is arranged. Via these openings the cartridges are slid onto the riser. They are prevented from floating upwards by means of frictional forces.
[0021] Furthermore or exclusively, means for a detachable connection between cartridge and container are preferably provided, which, for example, can also prevent the cartridge from floating upwards. In one configuration manual intervention is required in order to release the connection. The means are then preferably arranged on the upper face of the cartridge. These means preferably comprise frictional forces or latching means, so that for release of the connection as far as possible no additional hand grip other than the parting movement is necessary. It is not necessary to push the cartridges downwards for purposes of providing a sealing force, the hold-down device is required exclusively to prevent the cartridges from floating upwards.
[0022] The means for a detachable connection between the cartridges and the container can for example be embodied as grab handles, additional weights or latching mechanisms, which, depending upon the arrangement, engage or are arranged either underneath, above or laterally on the cartridge.
[0023] An outlet line is normally connected to the outlet of the container; this translates into a riser line for purposes of draining off the cleaned fluid, It is possible just to close the outlet and to vent the outlet line and riser line in order to replace the cartridges without the condensate gaining access to the clean water side. Replacement of the cartridges is thus possible without a complete drainage as far as a service tap that connects to the riser line further downstream. By this means downtimes for the separation device and thus also for replacement of the cartridges can be shortened.
[0024] In accordance with the disclosure a latching mechanism on the floor of the container is particularly advantageous. A sealing ring that is produced from an elastic material and has latching projections, has sufficient retaining force for a cartridge in order to prevent the latter from floating upwards. By virtue of the elasticity it is nevertheless possible to pull the cartridge in question upwards out of the sealing ring, since the latching projections are then deformed. A riser that is arranged within the cartridge in question is preferably positioned on the sealing ring located on the floor, whereby the latching projections of the sealing ring latch into corresponding openings or undercuts.
[0025] The sealing ring can preferably also be arranged in an opening of the cartridge that is positioned onto the upright riser or container. The latching projections of the sealing ring latch into corresponding openings or undercuts that are arranged on the riser of the container. The said variant has the advantage that when the cartridge or cartridge segment is changed over, the sealing rings are also removed, as a result of which any excess wear of the sealing rings is avoided.
[0026] In accordance with the disclosure the separation device can be used with a suction pump or pressure pump positioned upstream or downstream as a flow regulator. In all cases the objective is to maintain the prescribed through flow at all times, for which reason the pump is understood to be a flow regulator. In this manner significantly higher service lives are achieved for the segregation device. This is particularly advantageous if regular maintenance intervals are planned and a changeover of filter elements between the planned maintenance dates is to be avoided. The pump can be level-regulated or time-regulated. “Level regulation” is understood to mean that the pump switches itself on when an appropriate fill quantity is attained within the separation device. Alternatively, and in particular when there is a regular flow into the separation device, the pump can also be switched on in accordance with defined time intervals. A combination of the two options is also conceivable.
[0027] In accordance with the disclosure the cartridges have an essentially triangular cross-section, which is isosceles and right-angled. With 2, 4, 8 or 16 cartridges, etc. it is always possible to form a quadratic figure. The said arrangement offers the advantage that with a standardised cartridge container sizes with the cross-sectional ratios 1:2:4 etc. are achieved; these have the optimal ratio between cross-sectional area and perimeter.
[0028] A further essential advantage as a result of the use of a pump consists in the fact that the pump can operate in the reverse direction and thus the separation device can be cleaned by means of backwashing.
[0029] Advantageous configurations are in each case the subjects of the dependent claims. Here it is to be noted that the features individually embodied in the patent claims can be combined with one another in any technically logical manner so as to demonstrate further configurations of the disclosure.
BRIEF DESCRIPTION OF THE FIGURES
[0030] The disclosure is described in more detail on the basis of the following figures. The examples of embodiment shown are to be understood just as examples and are not designed to limit the disclosure to the features shown. Here:
[0031] FIG. 1 shows a first inventive form of embodiment of a separation device,
[0032] FIG. 2 shows a first variant of the arrangement of cartridges in a container,
[0033] FIG. 3 shows a second variant of the arrangement of cartridges in a container,
[0034] FIG. 4 shows a first variant of embodiment of a hold-down device for purposes of fixing a cartridge in the container,
[0035] FIG. 5 shows a second variant of embodiment of a hold-down device,
[0036] FIG. 6 shows a further representation of the arrangement of two cartridges in the container,
[0037] FIG. 7 shows a second representation of four cartridges in the container,
[0038] FIG. 8 shows a scrap section of a cartridge with a hold-down device located on the floor,
[0039] FIG. 9 shows an inventive sealing ring for purposes of fixing a cartridge in the container,
[0040] FIG. 10 shows a further variant of embodiment of the arrangement of cartridges in the container,
[0041] FIG. 11 shows a further variant of embodiment of the arrangement of cartridges in the container,
[0042] FIG. 12 shows a further variant of embodiment of the arrangement of cartridges in the container.
DETAILED DESCRIPTION
[0043] FIG. 1 shows an inventive form of embodiment of the separation device. In a container 2 are located a plurality of cartridges 4 , which are filled with a filter material 7 . A fluid, or a fluid mixture, is supplied via the single intake 3 to the container 2 , preferably continuously, and forms the fluid level 5 , in which the cartridges 4 are immersed. The filter material 7 serves to provide the separation of a fluid constituent of the fluid supplied to the container 3 , for example the separation of oil from a water-oil mixture. For example, the fluid that is separated has a lower specific density than the fluid with which it was mixed. The fluid flows through the filter material 7 , since the cartridge 4 is provided with an intake opening 8 . An outlet opening that is provided on each of the cartridges is connected in each case with an outlet 6 of the container in terms of fluid flow, and serves to drain off the filtered fluid. The flow path of the fluid is indicated by arrows.
[0044] FIGS. 2 and 3 show differing possible arrangements of the cartridges 4 in a container 2 , in each case in plan view. FIGS. 6 and 7 are related design drawings. In FIGS. 2 and 3 the oval intake openings 8 and levers 9 are also drawn in; on one hand the latter engage in the openings 8 and on the other hand are attached to the container 2 by means of a latching mechanism, on the one hand so as to provide a detachable connection, and at the same time to counter the buoyancy of the cartridge 4 in the fluid.
[0045] FIG. 4 shows a hinge-type design of the lever 9 ″ in the form of a simple film hinge, one arm of which can be moved for purposes of releasing the cartridge 4 . Furthermore a latching means 11 is provided, which interacts with a complementary latching means fitted to the container so as to provide the detachable connection. A gripping loop 10 eases the extraction of the cartridge 4 .
[0046] FIG. 5 shows a simple lever 9 , once again engaging in an opening of the cartridge 4 , as a connecting means between container and cartridge 4 . Whereas another possible arrangement, oppositely arranged, is demonstrated by 9 ″.
[0047] In FIG. 8 a detachable connection is demonstrated, in which by means of a floor-located latching mechanism between cartridge 4 and container 2 a detachable connection between these is fabricated. A riser 12 designed in the floor of the container 2 is inserted into the outlet opening 17 of the cartridge 4 . By this means a connection is fabricated between the cartridge 4 and the outlet 6 of the container 2 in terms of fluid flow. A sealing ring 15 with a surrounding sealing lip 14 is inserted into the outlet opening 17 of the cartridge 4 . The said sealing lip 14 latches under a circumferential latching projection 13 of the riser 12 and thus the detachable connection is fabricated.
[0048] FIG. 9 shows a representation in perspective of the sealing ring 15 in FIG. 8 . Next to the interior sealing lip 14 can be discerned latching projections 19 that are arranged outboard; these hold the sealing ring 15 within the outlet opening 17 , where they engage in corresponding undercuts or openings.
[0049] FIG. 10 shows a greatly simplified representation of the arrangement of cartridges 4 in the container 2 . The cartridges 4 are arranged stacked one above another, and using centrally arranged cartridge openings are attached to the central riser 12 . The fluid mixture gains access to the container 2 via the intake 3 , and, in the example of embodiment shown, flows from above into the cartridges 4 through appropriate inlet openings 24 . The fluid flows through the filter material 7 and gains access to the riser through riser openings 25 . The fluid is drained off through the outlet line 20 and the adjoining riser line 22 . The cartridges 4 are positioned on the riser 12 by simply sliding them onto the riser 12 . Cartridge sealing rings 26 are preferably provided for sealing purposes. The riser 12 is closed at its end, so that the fluid can only flow through the cartridges 4 into the riser.
[0050] FIG. 11 shows a similar variant of embodiment, in which the cartridges 4 are likewise arranged slid onto the riser 12 . In the said variant of embodiment the fluid mixture flows from underneath through inlet openings 24 into a cartridge intake segment 28 . In the example of embodiment shown the inlet openings 24 are arranged on a lower face of the cartridge intake segment 28 , that is to say, on the side facing towards the outlet 6 . The cartridge intake segment 28 is located completely within the fluid mixture. Via the riser 12 the filtered fluid gains access to a cartridge segment 34 that is located below, and is led via riser openings 25 into the filter material 7 of the cartridge segment 34 , which is otherwise totally sealed off from fluids, so that the fluid can only flow into the latter via the riser 12 . Within the cartridge segment 34 is provided an intermediate surface 36 , which again has inlet openings 24 . The inflowing fluid is uniformly introduced into the filter material 7 via the inlet openings 24 . The newly filtered fluid gains access back into the riser 12 via further riser openings 25 , and flows out of the separation device 1 . In this variant of embodiment the riser 12 is not closed at its end, instead it is led out of the container 2 so that, if so required, further fluids can be supplied to the riser line 22 when the container is being primed. Cartridge sealing rings 26 seal the segments 28 , 34 with respect to the riser and the surrounding fluid mixture.
[0051] FIG. 12 shows a further variant of embodiment of the arrangement of the cartridges 4 in the container 2 . A cartridge intake segment 28 is once again shown, into which the fluid mixture flows through inlet openings 24 . In the example of embodiment shown the inlet openings 24 are arranged on the upper face of the cartridge intake segment 28 , that is to say, on the side facing away from the outlet 6 . A riser 12 is not provided; the cartridge intake segment is located completely within the fluid mixture. The cartridge intake segment 28 has an outlet 30 , which leads into an intake 32 of a cartridge segment 34 arranged underneath the cartridge intake segment 28 . The cartridge segment 34 is otherwise totally sealed off from fluids, so that fluid can only flow into the latter through the intake 32 . Within the cartridge segment 34 an intermediate surface 36 is once again provided; in turn this has inlet openings 24 . The inflowing fluid is uniformly introduced into the filter material 7 via the inlet openings 24 . The cartridge intake segment 34 also has an outlet 30 , which, in the example of embodiment shown, leads out into the outlet 6 of the container 2 .
[0052] The individual segments 4 , 28 , 34 can be interconnected in a quick and simple manner, whereby sealing takes place via cartridge sealing rings 26 , which are arranged in the vicinity of the cartridge outlet 30 or the cartridge intake 32 .
[0053] For each of the variants of embodiment in accordance with FIGS. 10 to 12 it is true to say that one or more further cartridges 4 , cartridge intake segments 28 , or cartridge segments 34 , can be provided. In particular it is also possible to use a plurality of risers 12 , preferably arranged next to one another, with corresponding segments 4 , 28 , 34 .
[0054] The disclosure is not limited to the examples of embodiment described; these just serve to provide exemplary elucidations of the disclosure. | The invention relates to a separation device ( 1 ) for separation of a constituent from a liquid mixture ( 5 ), comprising a vessel ( 2 ), an inlet ( 3 ) and at least one outlet ( 6 ), said inlet ( 3 ) being arranged above the outlet ( 6 ), a filter material ( 7 ) capable of binding the constituent and is arranged within the vessel ( 3 ) between the inlet ( 3 ) and the outlet ( 6 ) such that flow passes through the filter material ( 7 ). The filter material ( 7 ) is arranged in a cartridge ( 4 ) inserted into the vessel ( 3 ). | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The description below relates to flexible thermoelectric circuits.
2. Description of the Related Art
Present Thermoelectric Modules (TEMs) use substrates to form the electrical paths to connect individual Thermoelectric Elements (TEEs). Generally, the connections are made so that one surface of an array of TEEs is heated and the opposite surface is cooled when current is passed through the array in a specified direction. Most TEMs have ceramic substrates with copper circuits to connect individual TEEs. The TEEs are soldered to the copper circuits. Other systems use printed and fired conductive ink circuits, and still others use circuits fabricated within the substrate structure itself and have the circuit pattern formed into a monolithic substrate/conductor structure.
In certain TEMs, Kapton or other high temperature organic substrates are used in combination with laminated or deposited copper circuit material. Such assemblies are processed using printed circuit technology to form the circuit pattern and electrically connect the TEEs. The substrate construction produces TEMs that are essentially rigid.
In TEM designs the substrates are on opposite sides of the TEEs forming a sandwich with the TEEs between the substrates. Because of this geometry, present substrates, even those that are polymer based, do not allow the TEM to flex to the degree needed. Furthermore, when such assemblies are bent forcefully, high shear forces are produced on individual TEEs which cause immediate failure or reduced life. In applications that involve exposure to thermal cycling, variable mechanical loadings, shock or vibration, bending and shear forces can occur repeatedly so the systems tend to have short life and can thereby make the use of TEMS impractical
SUMMARY OF THE INVENTION
Certain recent applications for TEMs benefit from the use of flexible TEMs that can be shaped to meet the geometrical constraints imposed by the optimized cooling and heating system performance. By employing such flexible TE systems, costs, size and complexity can be reduced and system capability improved.
Substrates are designed and constructed so that they can flex in one or more directions; the construction of such substrates follows certain design guidelines that are described in text and figures that follow. Several variations are described that can meet specific design needs such as (1) flexure in one and more than one direction; (2) designs for TEMs that flex and have zones that heat and others that cool on the same substrate surface; (3) systems that provide thermal isolation in accordance with co-pending U.S. patent application Ser. No. 09/844,818 entitled Improved Efficiency Thermoelectrics Utilizing Thermal Isolation; and (4) systems that are cascades or multi-layered.
Several embodiments and examples of thermoelectrics are described. A first embodiment involves a flexible thermoelectric that has a plurality of thermoelectric elements and first and second substrates. The substrates sandwich the plurality of thermoelectric elements and have electrical conductors that interconnect ones of the plurality of thermoelectric elements. At least one of the first and second substrates is constructed of a substantially rigid material, and the substrates are configured to flex in at least one direction.
For example, at least one substrate may be weakened, have cuts, be formed in sections, be shaped, be constructed of a material, or be modified in order to permit flexing. The flexible thermoelectric, in one embodiment, is for use with a fluid flow, and the sections or cuts are formed in a manner to improve thermal isolation from section to section in at least the direction of fluid flow. Other features may be provided to provide thermal isolation in the direction of fluid flow.
In one embodiment, the thermoelectric flexes in at least two directions. In another embodiment, the thermoelectric is constructed with a single layer of thermoelectric elements, and cools on a first side and heats on a second side, in response to an electrical current. Alternatively, or in addition, at least portions of the thermoelectric may have multiple layers of thermoelectric elements. In this manner, a first plurality of thermoelectric elements may be positioned along a first side of a central substrate and a second plurality of thermoelectric elements may be positioned along an opposing side of the central substrate. The first plurality of thermoelectric elements are sandwiched between the first substrate and the central substrate, and the second plurality of thermoelectric elements are sandwiched between said second substrate and the central substrate. In this embodiment, the flexible thermoelectric may be configured to provide both heating and cooling on one side of the thermoelectric, in response to a current flow.
In one embodiment, the flexible thermoelectric further has at least a first thermal conductor configured to provide heat flow to and/or from the thermoelectric. In addition, the thermal conductor strengthens the thermoelectric.
Another example of a flexible thermoelectric has a plurality of thermoelectric elements, and first and second substrates sandwiching the plurality of thermoelectric elements, wherein at least one of the first and second substrates is constructed in sections in a manner to permit flex of the thermoelectric in at least one direction.
At least one of the substrates may be weakened, formed in sections, have cuts, be of a material selected, or be shaped, to permit flexing. As with the previous embodiment, the flexible thermoelectric may be for use with a fluid flow, and the cuts may be formed in a manner to improve thermal isolation from section to section in at least the direction of fluid flow. In one advantageous embodiment, the flexible thermoelectric flexes in at least two directions.
Again, the flexible thermoelectric may also be constructed with a single layer of thermoelectric elements, or multiple layers of thermoelectric elements. The flexible thermoelectric may be configured to cool on a first side and heat on a second side, or to both cool and heat on the same side. For example, a first plurality of thermoelectric elements may be positioned along a first side of a central substrate and a second plurality of thermoelectric elements may be positioned along an opposing side of the central substrate, where the first plurality of thermoelectric elements are sandwiched between the first substrate and the central substrate, and the second plurality of thermoelectric elements are sandwiched between said second substrate and the central substrate. A thermal conductor may be provided for heat flow to and/or from the thermoelectric. In addition, a thermal conductor may be used to strengthen the thermoelectric.
In another embodiment, a flexible thermoelectric has a plurality of thermoelectric elements, and first and second substrates sandwiching the plurality of thermoelectric elements. In this embodiment, preferably, at least one of the first and second substrates is constructed in a non-uniform manner to permit flex of the thermoelectric in at least one direction. For example, at least one substrate is weakened in places, is formed in sections, has cuts in a plurality of locations, is shaped non-uniformly, or is formed of a material in certain locations in order to permit flexing. Where the thermoelectric is for use with a fluid flow, the cuts or sections or non-uniformities are preferably formed in a manner to improve thermal isolation in at least the direction of fluid flow. In one embodiment, the thermoelectric flexes in at least two directions.
The thermoelectric may be constructed with a single layer of thermoelectric elements, or with multiple layers of thermoelectrics. In this manner, the thermoelectric may be configured to cool on a first side and heat on a second side, and/or provide both heating and cooling on the same side. For example, a first plurality of thermoelectric elements may be positioned along a first side of a central substrate and a second plurality of thermoelectric elements may be positioned along an opposing side of the central substrate, the first plurality of thermoelectric elements sandwiched between the first substrate and the central substrate, and the second plurality of thermoelectric elements sandwiched between said second substrate and the central substrate.
A method of constructing a flexible thermoelectric is also disclosed, involving the steps of providing a plurality of thermoelectric elements, and positioning or forming the thermoelectric elements between first and second substrates, wherein at least one of the substrates is constructed of a substantially rigid material, and configured to permit flexing of the thermoelectric.
In accordance with the method, the substrates may be formed in sections, may be weakened in locations, may have cuts, may be shaped, and/or may be formed of material selected to permit flexing in one or more directions. Where the resulting thermoelectric is for use with a fluid flow, the method involves making the thermoelectric in a manner to improve thermal isolation in at least the direction of fluid flow.
The method may involve forming a single layer of thermoelectric elements, or multiple layers of thermoelectric elements. In this manner, the thermoelectric may be configured to provide heating on one side and cooling on another, and/or both heating and cooling on the same side.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a conventional TEM with a ceramic substrate.
FIG. 2 depicts a typical circuit pattern for a conventional TEM.
FIG. 3 depicts a substrate for flexible TEMs.
FIG. 4 depicts a TEM flexible in one direction.
FIG. 5 depicts a TEM flexible in two directions.
FIG. 6 depicts a TEM flexible in multiple directions.
FIG. 7 depicts a flexible TEM with heating and cooling in separate zones of the same substrate.
FIG. 8 depicts a multi-layer flexible substrate.
FIG. 9 depicts representative patterns for flexible conductors in a flexible TEM.
FIG. 10 depicts a TEM with enhanced heat transfer produced by secondary thermally conductive members.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1A depicts a conventional TEM 100 with substantially rigid first and second substrates 101 , 102 . Power supply 103 provides current to the TEM 100 . FIG. 1B depicts details of the TEM's 100 internal circuitry. P-type 104 and N-type 105 TEEs alternate and are electrically connected in series through circuits 106 and 107 . The circuits 106 and 107 are attached to the substrates 101 and 102 , respectively.
When the TEM 100 is connected to the power supply 103 , the electrons flow in the direction indicated by arrows 108 . All of the electrons flow from P-type TEEs 104 to a circuit 106 to N-type TEEs 105 on the first substrate 101 side. On the second substrate 102 side, exactly the opposite occurs. Electrons always flow from the N-type TEEs 105 through circuits 107 to P-type TEEs 104 . Under these circumstances, the flow of heat is shown by the arrows, with q c indicating cooling at substrate 101 and q h indicating heating at substrate 102 . The power in is denoted by q in . T c indicates the temperature of the first substrate 101 , and T h indicates the temperature of the second substrate 102 .
FIG. 2 depicts in more detail a typical circuit pattern for the principal components of the TEM of FIG. 1. A first upper substrate 201 consists of a series of electrically conductive circuits 203 to which are soldered or otherwise uniformly and electrically connected TEEs 204 , 205 , 206 , 207 , 208 and 209 . In this configuration, every circuit 203 has two TEEs, one N-type and one P-type, attached. A corresponding second or lower substrate 202 has electrically conductive circuits 203 attached. The lower substrate 202 also has two electrical wires 210 and 212 electrically attached to two of the circuits 203 , the wires 210 and 212 are shown sheathed in insulation 211 and 213 , respectively.
When assembled, the upper substrate 201 is positioned with respect to the lower substrate 202 so that the two ends of the TEE 204 engage circuits 203 . Similarly, TEEs 205 , 206 , 207 , 208 and 209 ends are engaged as shown. Current enters through the wire 210 and passes upward from the lower substrate 202 to the upper substrate 203 through the TEE 205 . It then passes along the circuit 203 to the TEE 206 , and so on, as was illustrated in FIG. 1 . This pattern continues through TEE 208 where the circuit 203 connects to TEE 209 on the lower substrate 202 . The current passes through 209 to the upper substrate 201 , and along the second set of circuits 203 which are interconnected through TEEs (not shown). The current continues to pass through circuits 203 and TEEs until it reaches TEE 204 and circuit 203 . From there the current exits the TEM through wire 212 .
Current is directed along the desired paths by electrically isolating the separate circuits 203 by electrically insulative areas 214 .
Generally, it is desirable that the upper and lower substrates 201 and 202 are constructed of electrical nonconductive materials such as alumina ceramic or the like. Preferably, the substrate materials have as high a thermal conductivity as possible perpendicular to the plane of FIG. 2 so that heat can be transported through the substrates to the outer faces of the assembled TEM with as little temperature change as possible. The circuit material and the circuit 203 design should maximize electrical conductivity between adjacent TEEs. This combination of design and material properties held minimize thermal and electrical losses in the TEM.
FIG. 3A depicts an example of a substrate system 300 wherein at least one of the substrates is constructed of a substantially rigid material in one preferred embodiment. The upper substrate 301 is made from a high thermal conductivity flexible material preferably such as Kapton polyamide film, very thin fiberglass, or any other flexible material. Circuits 303 are on the upper substrate in a pattern. Similarly, a lower substrate 302 , which is preferably, but not necessarily, of a substantially rigid material, has circuits 315 arranged in a pattern on it. TEEs 304 , 305 , 306 and 307 are some of the TEEs in the TEM. Wires 309 and 311 each attach to a circuit. Insulation 310 and 312 sheathe the wire.
The upper circuit 301 is connected to the lower circuit 302 so that the respective ends of the TEEs 304 , 305 , 306 and 307 mate at the positions indicated in FIG. 3 A. The TEEs are of N-type and P-type and are arrayed with the circuits 303 and 315 so that current flows alternately through each type of material. The pattern is such that current flows from one wire 309 through the TEM 300 to the other wire 311 , as was described in detail in FIG. 2 .
Preferably, after assembly of the TEM, slots are cut into the lower substrate at positions 313 so as to separate the lower substrate 302 into segments. The upper substrate 301 can flex in the areas 308 if the circuits 303 can flex so as to not degrade the TEE circuit 303 electrical connection. By separating the substrate 302 at several locations, the TEM can be flexed in a concave direction with respect to the outer surface of the TEM upper substrate 301 . Furthermore, if a cut 314 is made in the upper substrate 301 at several locations, and the cuts 316 are made in the lower substrate 302 , the TEM can be twisted about its length as well as bent. In addition, if slots are made in the lower substrate 302 so as to remove material as shown at 313 , the TEM can flex in both directions.
The general description of FIG. 3A holds for an even number of TEEs in a horizontal row. For larger number of TEEs, there will be one circuit 315 for every two TEEs added in each row of the lower substrate 302 . One circuit 317 is added for each circuit 315 added.
FIG. 3B depicts a configuration 320 with an odd number of TEEs (for example, 325 , 326 and 327 ) in each horizontal row. For the geometry, both the upper substrate 321 and the lower substrate 322 have both horizontal and vertical circuits 323 and 324 . As in FIG. 2, the assembly consists of N and P-type TEEs, and circuits arranged as described therein. Wire assemblies 333 and 334 are attached at the ends. Cuts 329 and 330 are made respectively in the upper substrate 321 and the lower substrate 322 at the locations shown.
When the TEM is assembled, for example, current enters through wire assembly 333 and into TEE 325 and so on until it exits at the wire assembly 324 , after passing through the TEE 335 . Again, the TEEs are alternately P and N-types so that as current passes, one side is heated and the other cooled. The cuts 329 and 330 allow the assembled TEM to flex in two directions if the circuits 323 and 324 can flex or bend at 331 and 332 . If the cuts 329 and 330 are formed as slots with the removal of substrate material, the corresponding flexure points can bend in both directions. Finally, if cuts 336 and 337 are incorporated, the assembled TEM can twist about its length.
In FIGS. 3A and 3B TEMs 300 and 320 form separate arrays. As a part of the present invention, part of a TEM can be of one type and other parts of the other type.
FIG. 4 depicts a TEM 400 with an upper substrate 401 and cut lower substrate 402 . Again, in this embodiment, the lower substrate material is substantially rigid, but is modified or configured in a manner to be flexible. In this configuration, dividing the substrate into sections permits the flexibility. Wire assemblies 406 and 407 are attached at each end. In accordance with the geometry of FIG. 3A, each row has an even number of TEEs 405 and 408 . The TEEs are connected via circuits (not shown) as in FIG. 3 A. The circuits, in practice, generally are very thin, such as printed circuit traces. Therefore, the circuits are often not shown in the Figures herein, except to illustrate the manner in which the circuits connect the individual TEEs.
The TEM has been bent in the principal direction indicated in the description of FIG. 3 A. Spaces 403 develop because of the flexure. For descriptive purposes, the lower substrate 402 has not been cut at location 404 and therefore, that segment does not have a bend to it.
FIG. 5 depicts a TEM 500 formed according to FIG. 3 B. It consists of a lower substrate 501 , preferably but not necessarily constructed from substantially rigid material with cuts 505 and 506 to permit flexing and an upper substrate 502 with cuts 503 and 504 . TEEs and electrical paths are connected as discussed in FIGS. 2 and 3B.
The TEM 500 is shown flexed in two directions. The cuts 503 are spread open and form gaps in the upper substrate 502 where TEM 500 is flexed in one direction while other cuts 504 are not open where TEM 500 is flexed in the opposite direction. Similarly, in lower substrate 501 , cuts 505 are closed while cuts 506 are open.
As noted in the discussion of FIGS. 3A and 3B, where material is removed (as an example, regions at slots 504 and 505 ) such locations contribute to flexure since the substrates 501 and 502 are able to flex at those locations as well.
FIG. 6 depicts a TEM 600 of the type described in FIG. 3 A. Wire assemblies 608 and 609 are attached to the lower substrate 601 . Upper substrate 602 and TEEs 603 are connected with circuits (not shown) as discussed in FIG. 3 A. Slots 606 are in the upper substrate 602 . Opposite the slots 606 are partial cuts not visible in FIG. 6, but of the type shown as slot 314 of the upper substrate 301 in FIG. 3 A.
The TEM 600 is depicted as twisted about its length so that the upper substrate 602 is vertical at location 607 and horizontal at the opposite end 610 . The two adjacent circuits at 604 and the two adjacent circuits at 605 act as rigid units since there is no twist in the TEM 600 at these points. Twisting occurs at slots 606 in the upper substrate 602 and the partial slots (not shown) at the corresponding location in lower substrate 601 . TEEs 603 are connected via a circuit (not shown) that is adjacent to a partial slot in the lower substrate 601 . Current can pass through the TEM 600 via wire assemblies 608 and 609 .
FIG. 7 depicts a TEM 700 with the upper substrate 701 , 703 and 705 and a lower substrate 702 , 704 and 706 , circuits (not shown), and TEEs 712 , 713 , 715 and 716 . The upper substrate 701 is folded upon itself at fold 708 . Grease 707 , solder or other high thermal conductivity material fills the space between the two segments of the upper substrate 703 and 705 . A circuit as described in FIG. 2 (not shown), connects TEE 712 to TEE 713 . The circuit pattern is either that of FIG. 3A or 3 B. At the fold 708 , the TEEs 712 and 713 are both of the same type. All other TEEs are alternately N-type and P-type and are connected as described in FIG. 2 .
As an example, during operation, current enters at wire assembly 713 and passes through an N-type TEE 715 and on through the first of the TEM 700 and exits through TEE 716 at wire assembly 714 . With this as an example, the lower substrate surface 706 is cooled and the upper substrate surface 705 is heated. The heat generated is conducted to the upper substrate surface 703 by the grease 707 . Since the two connecting TEEs 712 and 713 are of the same type and all others are electrically connected in series and of alternating type, the upper substrate surfaces 701 and 703 are cooled and the lower substrate surfaces 702 and 704 are heated. The upper substrate surface 703 removes the heat generated at the upper substrate surface 705 and cools that surface, so that the lower substrate surface 706 is significantly colder than the portion of the upper substrate surface 701 , not contact with substrate surface 705 . Thus, a typical TEM cascade is formed in the region of the contact zone 707 , and a single stage TEM is formed elsewhere. With this geometry, design of the TEEs in the regions between substrate surfaces 705 and 706 and also between 702 and 703 , can be of a form well known to the art.
It is clear that other levels could be added to the cascade region of TEM 700 , and that multiple separate cascades could be fabricated by one or more flexible TEMs employing the above concepts and simple extensions thereof.
FIG. 8 depicts another variation of a TEM 800 . Herein, a backbone substrate 801 has circuits on each side preferably of the type of upper substrate 301 of FIG. 3 A. The TEM 800 has two additional substrates, an upper substrate 802 and a lower substrate 804 . Each has slots 807 formed by removing substrate material. Between the upper substrate 802 and the backbone substrate 801 are TEEs 803 and between the backbone substrate 801 and the lower substrate 804 are TEEs 805 . The TEEs 803 and 805 are alternately N-type and P-type and are connected by circuits, as in FIG. 3A (not shown). In this example, the components are electrically connected so that the portion above the insulation layer in the backbone substrate 301 forms one TEM circuit with wire connections 808 and 809 and the portion below forms a separate TEM circuit with wire connections 810 and 811 .
The TEM 800 operates by passing current from, for example, 808 to 809 and a separate current from 810 to 811 . In this example, the current flows so that the upper substrate 802 is cooled and hence the upper surface of the backbone substrate 801 is heated. Heat passes through to the lower surface of the backbone substrate 801 , which is the cooled side of the lower portion. The lower substrate 804 is therefore heated. Thus, in this example, the TEM 800 is a cascade system. Alternately, the backbone substrate 801 could be wider, thermal energy transferred through the added width, and the currents could flow so that the backbone substrate 801 was heated or cooled by both the upper and lower TEMs.
Currents, TEE materials, number of TEEs and TEE dimensions can differ anywhere within the TEM 800 to achieve specific design and performance objectives. Also, the upper substrate 802 and the lower substrate 804 need not be the same dimensions or exact shape, thus, for example, a portion 812 of the lower substrate 804 need not have a corresponding part of the upper substrate 802 , directly in thermal contact with it. As additional examples, the upper substrate 802 could be of the type shown in FIG. 3 B and the lower substrate 804 of the type shown in FIG. 3 A. Or, the upper substrate 302 could have fewer TEEs in each row compared to the lower substrate 804 and the total number of TEEs could differ among rows. Also, the electrical connections could be modified to pass current from the upper circuits of TEM 800 to the lower circuits so that two of the wires, for example, 809 and 811 , would be eliminated. Other connection changes could be made to modify performance at certain locations, or to achieve other purposes.
The flexible TEMs described herein will often have improved thermal isolation as explained in co-pending U.S. patent application Ser. No. 09/844,818 entitled Improved Efficiency Thermoelectrics Utilizing Thermal Isolation, filed Apr. 27, 2001. As explained in that application, when the thermoelectric is utilized for heating or cooling of a flowing fluid, thermal isolation in the direction of flow improves the efficiency of the thermoelectric. Therefore, as an example, the cuts in FIGS. 4, 5 and 8 , or sections of substrates may be made to correspond, where practical, to provide improved thermal isolation between sections separated by the cuts, in order to improve overall efficiency of the flexible thermoelectric.
FIG. 9 depicts a portion of a substrate 900 that consists of flexible substrate material 901 , circuits 902 and 903 , solder mask 904 , TEEs 905 and slot 906 . In this design, the assembly incorporates substrate 900 to mechanically connect parts.
The circuit 902 is of the form previously discussed in FIGS. 3A and 3B. Circuit 903 depicts a method for allowing that circuit to flex in the region between TEEs 905 . In this configuration, solder mask 904 covers a portion of the circuit 903 so as to prevent solder from accumulating where it is so covered. If the substrate 901 is flexed, bending will occur preferentially in the solder mask 904 region, since the circuit 903 does not have solder build up there and hence, is thinnest and most easily flexed there. Such preferential bending reduces mechanical stress at the interface of the TEE 905 and circuit 903 .
FIG. 9B depicts another geometry 920 which achieves flexure. Flexible substrate material 921 has circuits 922 and 923 attached, TEEs 924 and an elongated slot 926 . Sections 925 of the circuit 923 have been omitted.
The geometry 920 is known to the flexible circuit industry as a design that allows severe or repeated flexure with good stability. Further, by proper design, known to the art, solder accumulation in the flexure can be either prevented or reduced to acceptable levels and shear stresses induced during flexure (at the circuit 923 and substrate 921 interface) can be reduced.
Other designs for electrically conductive flexures, such as circuits that incorporate components not attached to the substrate (e.g., shunt wires and strips, electrically conductive hinges, and the like) can be employed to allow needed movement and are the subject of this invention.
FIG. 10 depicts a portion 1000 of a TEM of the present invention. It consists of an upper substrate 1001 with circuits 1002 and upper thermal conductors 1003 attached. A lower substrate 1005 has circuit 1006 and thermal conductor 1007 attached. TEEs 1004 are electrically connected to the circuits. Slots or cuts 1008 are in the upper substrate 1001 to allow flexure.
The thermal conductors 1003 and 1007 are designed to increase and distribute heat flow to and from the TEM. The conductors 1003 and 1007 are useful in high-power TEMs since typical substrate materials have relatively low thermal conductivity, and thereby reduce TEM performance. Performance can be improved by utilizing thermal conductors to increase thermal energy transport across the substrate and also mechanically strengthen the TEM. These improvements can be done by (1) maximizing the surface area of the circuit substrate and thermal conductor interface, (2) minimizing thermal resistance across the interfaces by selecting materials or material composites that minimize interfacial thermal resistance, or (3) utilizing the thermal conductors as structural members so that the substrate can be thinner, weaker or otherwise allow selection from a broader class of electrical insulators. These provide examples of designs that achieve enhanced performance, cost reduction, improved durability, size reduction and other benefits by utilizing additional componentry with the substrate. The above are presented as examples, and they do not cover all variations or otherwise restrict the scope of the invention.
In the discussion of FIGS. 3 through 10, it was stated that the substrate could have cuts, slots and sections removed to achieve flexure and bending. The same effect can be achieved by utilizing substrates that are mechanically weak. For example, the substrate could be made of a soft or weak material such as Teflon TFE, a silicone rubber, or the like; it could be made very thin; it could be mechanically weakened by incorporating holes, porosity, and making it from felt or the like; could be chemically weakened, treated to have its flexibility increased in selected areas, etched or the like; it could be fabricated with areas weakened, omitted, treated or otherwise modified, made thinner, slotted or the like that frees adjacent TEEs to move toward or away from one another so as to allow flexure and/or twisting within the TEM. The substrate could be completely omitted from the TEM so that unconstrained circuits would connect TEEs. Upon installation (and after flexure), the circuits could be attached to a structural material wherein the bonding agent or the structural material serves the function of a substrate within the system.
Although several examples and embodiments of flexible thermoelectric modules have been described above in various configurations, any flexible thermoelectric module and any variations of those embodiments described above are contemplated. Accordingly, the scope of the present invention is defined by the claims and not by any particular example. The examples above are meant to be illustrative and not in any way restrictive. In addition, the language of the claims is intended in its ordinary and accustomed meaning, without reference or special definition to any of the terms or limitation to the embodiments of those terms in the specification. | A flexible thermoelectric circuit is disclosed. Thermoelectric circuits have traditionally been of the rigid or substantially rigid form. Several different embodiments of thermoelectric circuits are disclosed which permit flexion in one or more directions to permit applications where flexible thermoelectric circuits are advantageous. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a jumper structure, more in details, relates to a jumper structure suitable for being used in a precision apparatus a thickness of which is restricted such as a watch.
[0003] 2. Description of the Prior Art
[0004] It is well known in a watch or the like to use a jumper structure rotating a date indicator for indicating date by a date feeding finger engaged with a teeth portion of the date indicator and having a jumping and restricting portion loaded by a spring and engaged with the teeth portion of the date indicator to stop rotation of the date indicator at every pitch of the teeth.
[0005] According to the jumper structure, the jumping and restricting portion is thickly formed in order to make engagement between the jumping and restricting portion and the teeth portion of the date indicator difficult to disengage even when impact by dropping or the like is applied to the watch. When the thick jumping and restricting portion is used, the jumping and restricting portion is formed by resin (plastic) in order to minimize mass (weight). Meanwhile, since the spring portion is always applied with load and therefore, it is difficult to use a resin which is difficult to avoid a creep phenomenon owing to plastically flowing performance and a metal material is used as a material of the spring portion. As a result, typically, the jumper structure is provided with a mode of a composite structure constituted by mutually fixing and coupling the jumping and restricting portion made of a resin and the spring portion made of a metal.
[0006] However, according to such a composite structure, not only part cost or fabrication cost is liable to increase but also there is a concern that a dispersion is liable to cause in a property of the composite structure.
[0007] Further, although there is known a constitution in which a jumping and restricting portion and a spring portion are integrally formed by a metal material having spring performance, when the jumping and restricting portion is thinned to minimize weight, there is a concern that engagement between the jumping and restricting portion and a teeth portion of a date indicator is liable to disengage.
[0008] Meanwhile, recently, there has been proposed to make a coil spring by molding a carbon nanofiber by a resin.
SUMMARY OF THE INVENTION
[0009] The invention has been carried out in view of the above-described various points and it is an object thereof to provide a jumper structure which is light-weighted and capable of reducing fabrication cost and a timepiece using the same.
[0010] In order to achieve the above-described object, according to the invention, there is provided a jumper structure integrally molded with a jumping and restricting portion made of a carbon nanofiber and a spring portion made of a carbon nanofiber.
[0011] According to the jumper structure of the invention, since the spring portion is made of carbon nanofiber, even when load or stress is always applied to the spring portion, there is rarely a concern of reducing spring performance by a creep phenomenon or plastic flow. Further, according to the jumper structure of the invention, since the jumping and restricting portion is made of carbon nanofiber, the specific weight of the jumping and restricting portion is smaller than that of a rigid metal material or the like and therefore, there is not a concern of excessively increasing the weight of the jumping and restricting portion and the thickness of the jumping and restricting portion can be increased. Therefore, there can be minimized a concern of disengaging engagement between the jumping and restricting portion of the jumper structure and a teeth portion engaged with and restrained by the jumping and restricting portion. Further, according to the jumper structure of the invention, since the jumping and restricting portion and the spring portion are integrally molded, integration cost of the jumper structure can be minimized. Further, according to the jumper structure of the invention, since both of the jumping and restricting portion and the spring portion which are integrally molded, are made of carbon nanofiber and can be formed typically by a material having substantially the same or similar composition, integral performance thereof can highly be maintained.
[0012] Further, according to the jumper structure of the invention, since the jumping and restricting portion is made of carbon nanofiber, the frictional coefficient of the jumping and restricting portion is small and therefore, force necessary for releasing stop by the jumping and restricting portion, is sufficed by minimum force larger than resistance or load prescribed by shapes of the jumping and restricting portion and the teeth portion and strength of a spring of the spring portion and energy consumption necessary for causing jumping operation or jumping and restricting operation can be minimized. Further, when the frictional coefficient of the jumping and restricting portion is large, a dispersion in frictional force caused by a dispersion in the frictional coefficient also becomes large, there is a concern of enlarging a dispersion in force necessary for releasing stopping by the jumping and restricting portion and it is necessary to design a rotational drive system of a date indicator or the like in consideration of a maximum value of the dispersion, however, according to the jumper structure of the invention, such an excessive design can be restrained to a minimum.
[0013] In the specification, with regard to the jumping and restricting portion and the spring portion, “made of carbon nanofiber” signifies to include carbon nanofiber as a major component such that a property of carbon nanofiber that the specific weight is small can be made full use and stable spring performance with no creep can be brought about and a rate of carbon nanofiber falls in a range of about 1% through about 60% in weight. Further, a coupling material or a binder for mutually coupling carbon nanofibers in order to integrally mold the jumper structure, may be constituted by a resin or the like, may include a resin or the like, may be constructed by a constitution produced by baking and actually carbonizing a resin or the like so far as the coupling material or the binder falls in a range capable of substantially avoiding the creep phenomenon or flow of composition in the binder material of the spring portion.
[0014] The integrally molded jumper structure made of carbon nanofiber may be formed by mixing power of carbon nanofiber to, for example, thermoplastic plastic, molding by injection molding or powder molding and baking the mixture to thereby substantially sinter the mixture while carbonizing the plastic material, or may be formed by mixing the powder with a material of thermosetting plastic, molding by compression molding or transfer molding or the like and baking the mixture to thereby substantially sinter the mixture while carbonizing the plastic material.
[0015] Although carbon nanofiber used in molding is typically constituted by so-to-speak single layer carbon nanotube, the carbon nanofiber may be constituted by a plural layers (multiple layers) or may be mixed with single layer ones and plural layer ones. In the case of multiple layers, two or three layers thereof may be laminated and more layers, for example, several tens layers thereof may be laminated. Depending on cases, several hundreds layers or more thereof may be laminated. Further, the carbon nanofiber may be constructed by a constitution having a constant diameter or chiral angle or spiral pitch thereof or mixed with constitutions having different diameters and chiral angles. Further, a diameter or the like of the respective carbon nanofiber per se may not be constant. Further, although carbon nanofiber typically comprises only carbon, depending on cases, small particles of carbon of other kind (small particles in the form of graphite, small particles in the form of amorphous carbon, small particles in the form of carbon black or the like) or other kind of atoms, molecules or small particles or the like may adhere to a surface of the nanofiber or mixed with nanofiber particles.
[0016] In molding, carbon nanofiber typically comprises powder or a small particles such that the carbon nanofiber is easy to be dispersed uniformly in a comparatively small amount of a resin material for constituting a binder and a diameter thereof falls in a range of about 1 nm (nanometer) through about several tens nm and a length thereof falls in a range of about several nm through several thousands nm. Further, an aspect ratio thereof is equal to or larger than 50.
[0017] In molding by using a resin material, it is preferable that a rate of a molding material such as a resin material is comparatively small in order to minimize the change in dimension and shape by carbonizing and sintering after molding the resin. When small particles of carbon nanofiber are small and a molding material including a resin material and a molding assisting agent added as necessary, can be provided with sufficient fluidity, there is used injection molding utilizing a thermoplastic resin or compression molding or transfer molding utilizing thermosetting resin material. In this case, a rate of small particles of carbon nanofiber is preferably equal to or higher than, for example, about 50% in volume, depending on cases, the rate may be smaller, for example, may be about 20 through 30% in volume. Further, when the rate of the carbon nanofiber is increased, powder molding may be carried out in the state of powder along with a small amount of a binder.
[0018] Carbonizing and baking (typically sintering) after molding a resin are typically carried out after removing the product from a molding die. However, when desired, after molding, at inside of the molding die, the product may further be carbonized or carbonized and baked. Further, a degree of carbonizing and baking may pertinently be selected in accordance with spring performance to be provided to the spring portion of the jumper structure and low frictional performance desired in the jumping and restricting portion. For example, in carbonizing, the resin may partially remain so far as plastic fluidity particular to resin can be avoided from being caused at a portion for constituting the spring portion and a degree of sintering by baking may be restrained to be low when the resin can operate partially as a binder between carbon nanofibers. Temperature, time period and atmospheric condition of sintering by carbonizing or baking may pertinently be changed in accordance with kind and rate of a resin material.
[0019] Further, although according to the above-described, an explanation has been given such that a total of the jumper structure is formed by one kind of a blend material and under the same carbonizing and baking condition, the spring portion and the jumping and restricting portion may be formed by materials having different blending rates or the spring portion and the jumping and restricting portion may be carbonized or baked (sintered or the like) at different temperatures.
[0020] In order to prevent engagement between the jumping and restricting portion and the teeth portion to which the jumping and restricting portion is engaged, from being disengaged in the axial line direction of the teeth, as described above, it is preferable that the thickness of the jumping and restricting portion with regard to the axial line direction is comparatively large and typically, the jumping and restricting portion (more in details, a jumping and restricting finger portion of the jumping and restricting portion) is formed more thickly than the spring portion. However, for example, when a thickness of the spring portion with regard to the above-described axis line direction, that is, a length of the spring portion in the width direction is made comparatively large, the jumping and restricting portion and the spring portion may be constituted by the same degree of thickness or the spring portion may be thicker than the jumping and restricting portion. Further, the thickness of the teeth portion in the axial line direction, is comparatively small typically in order to minimize mass of the teeth portion and therefore, the jumping and restricting portion is typically formed to be thicker than the teeth portion.
[0021] In order to minimize a concern of disengaging engagement between the jumping and restricting portion and the teeth portion in the axial line direction of the teeth portion by impact of drop or the like, the jumping and restricting portion is provided with a restricting portion for restricting a positional shift of the jumping and restricting portion in the thickness direction of the jumping and restricting portion relative to the teeth portion engaged with the jumping and restricting finger portion of the jumping and restricting portion. However, when the jumping and restricting portion is thick, the restricting portion may be dispensed with. The restricting portion is typically projected in an eaves-like shape to be opposed to an end face in the axial line direction of the teeth portion by being brought into contact with or locked by the end face to thereby enable to restrict the positional shift in the axial line direction. Although the eaves-like projected restricting portion may be constituted by a rod-like shape, the portion typically comprises a projected portion in a flat plate shape and in an eaves-like shape broadly projected to be able to be brought into contact with end faces of the plurality of teeth of the teeth portion. In this case, typically, by the restricting portion comprising the projected portion in the flat plate shape and in the eaves-like shape, a positional shift in the axial line direction between the jumping and restricting finger portion of the jumping and restricting portion and the teeth portion is restricted, thereby, engagement between the both can be prevented from being disengaged. Further, since the jumping and restricting portion is made of carbon nanofiber having the small specific weight and therefore, even when the jumping and restricting portion is provided with such an extra restricting portion, an increase in the mass is restrained to the minimum and excessive load can be avoided from applying to the rotational drive system or the like.
[0022] Such a jumper structure is typically used in a precision apparatus or the like a thickness of which is desired to be restrained to a minimum as in a watch or the like. In that case, such a jumper structure is engaged with a wheel for indicating date as in a date indicator or a day indicator of a timepiece and a wheel having teeth at a peripheral face thereof, that is, a teeth portion of a toothed wheel to restrain rotation of the toothed wheel. However, it is apparent that the jumper structure can be integrated to other arbitrary machine or apparatus.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0023] A preferred form of the present invention is illustrated in the accompanying drawings in which:
[0024] [0024]FIG. 1 is an explanatory plane view of a watch using a date jumper structure constituting a jumper structure according to a preferable embodiment of the invention (state removed of a case, a dial and the like);
[0025] [0025]FIG. 2 is an explanatory plane view showing to enlarge a state of settling (locking) of the date jumper with regard to the watch of FIG. 1;
[0026] [0026]FIG. 3 is an explanatory plane view showing to enlarge a state of jumping (jumping and restricting) of the date jumper with regard to the watch of FIG. 1;
[0027] [0027]FIG. 4 is an explanatory sectional view taken along a line IV-IV of FIG. 3; and
[0028] [0028]FIG. 5 is an explanatory perspective view of the date jumper of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Next, an explanation will be given of a preferable mode for carrying out the invention in reference to a preferable embodiment shown by the attached drawings.
[0030] According to a watch 1 constituting a timepiece according to a preferable embodiment of the invention, as is known from FIG. 1 through FIG. 4 shown by a state of removing a case or a frame, a hand and a dial, a teeth portion of an outer periphery of a date indicator driving wheel 4 is brought in mesh with a teeth portion of an outer periphery of an hour wheel 3 attached with an hour hand and rotated relative to a main plate 2 around a central axis line C 1 and during a time period in which the hour wheel 3 is rotated by two rotations in a D1 direction around the axis line C 1 , the date indicator driving wheel 4 is rotated by one rotation in a D2 direction around an axis line C 2 . Further, numeral 5 designates a minute wheel and a teeth portion of an outer periphery of the minute wheel 5 is brought in mesh with the teeth portion of the outer periphery of the hour wheel 3 and is brought in mesh with a center wheel & pinion (not illustrated) at the teeth portion of the outer periphery and transmits rotation of the center wheel & pinion to the hour wheel 3 by reducing the speed to {fraction (1/12)}. In FIG. 4 showing a section taken along a line IV-IV of FIG. 3, numerals 51 and 52 designate a stator and a rotor coil block of a motor 50 .
[0031] For simplifying the explanation, in the following, in FIG. 1, a face in parallel with a face of the drawing is defined as X-Y plane and a direction directed to this side orthogonally to the plane is defined as Z direction.
[0032] The date indicator driving wheel 4 is provided with a date feeding finger 6 projected in Z direction at an end face on a top side thereof. The main plate 2 is provided with a recessed portion 7 substantially in a ring-like shape having a circular inner peripheral face 7 a having a large diameter and outer peripheral faces 7 b and 7 c prescribing a portion of a circle having a small diameter and the recessed portion 7 is loosely fitted with a date indicator 8 in a ring-like shape in a state of leaving a clearance anticipating a maximum tolerance amount. The date feeding finger 6 can be engaged with teeth 10 of a teeth portion 9 of an inner peripheral face of the date indicator 8 having a larger diameter and substantially in a ring-like shape and during a time period in which the date indicator driving wheel 4 is rotated by one rotation, the date feeding finger 6 is engaged with one of the teeth 10 of the teeth portion 9 of the date indicator 8 and rotates the date indicator 8 by one pitch in a D3 direction.
[0033] Although a center cylinder portion 11 and a shaft portion 12 of the hour wheel 3 and the date indicator driving wheel 4 are supported by portions constituting bearings (not illustrated) at least on one end sides thereof, the date indicator 8 in the ring-like shape having the large diameter is only loosely fitted by the recessed portion 7 of the main plate 2 and is not provided with a shaft portion to be supported thereby. Therefore, displacement of the date indicator 8 in −Z direction relative the main plate 2 is restricted by a bottom face 13 (FIG. 4) of the recessed portion 7 of the main plate 2 and displacement thereof in +Z direction relative to the main plate 2 is restricted by a date indicator holder 14 shown by imaginary lines in FIG. 1 through FIG. 3 and partially shown by bold lines in FIG. 4. Further, although the date indicator 8 is typically provided with a thickness of, for example, about 0.2 mm, the thickness may be thicker or thinner than 0.2 mm. The date indicator holder 14 is provided with notched portions 17 and 18 or the like and at inside of the notched portion 17 , the date feeding finger 6 of the date indicator driving wheel 5 is projected in +Z direction and is movable in the notched portion 17 and at the notched portion 18 , a jumping and restricting portion 23 of a date jumper 20 constituting a jumper structure is projected in +Z direction and is movable in the notched portion 18 in a face in parallel with X-Y plane in E1 and E2 directions as described later.
[0034] The date jumper 20 is provided with a bearing hole 21 fitted to a shaft portion 15 formed at the main plate 2 , and is provided with a base portion 22 rotatable around a rotational axis line or rotational center C 3 in E1 and E2 direction, the jumping and restricting portion 23 for restricting rotation of the date indicator 8 in D2 direction, a rigid shaft portion 24 connecting the base portion 22 and the jumping and restricting portion 23 and a spring portion 27 substantially in a U-like shape extended from a side face 26 of a base end portion 25 of the rigid shaft portion 24 to deviate the jumping and restricting portion 23 of the date jumper 20 in E1 direction around the axis line C 3 . The spring portion 27 may be constituted by other arbitrary shape such as a simple linear shape or a bow shape or an arc shape or the like in place of the U-like shape so far as the spring portion 27 can exert deviating force in E1 direction to the jumping and restricting portion 23 .
[0035] The jumping and restricting portion 23 is provided with jumping and restricting faces or engaging side faces 29 and 30 having a converging shape prescribing a jumping and restricting finger portion 28 for locking rotation of the date indicator 8 by fitting into an interval between a pair of the contiguous teeth 10 , 10 constituting the teeth portion 9 at the inner periphery of the date indicator 8 and engaging with the contiguous teeth 10 , 10 . Further, the engaging side faces 29 and 30 are intersected at a front end portion 31 and the end portion 31 rides over a front end 10 a of one of the teeth 10 in jumping or in jumping and restricting. Further, although the front end 31 is typically constituted by a dot-like shape in plane view, depending on cases, the front end 31 may be constituted by a projected shape projected to bend.
[0036] That is, during most of a time period in one rotation of the date indicator driving wheel 4 , the date feeding finger 6 of the date indicator driving wheel 4 is disposed at a location remote from the teeth 10 of the teeth portion 9 of the date indicator 8 and as shown by FIG. 2, the date jumper 20 is deviated around the center axis line C 3 in E1 direction by spring force of the spring portion 27 and the jumping and restricting finger portion 28 of the jumping and restricting portion 23 is engaged with the pair of teeth 10 , 10 of the date wheel 8 to thereby lock rotation of the date indicator 8 . Meanwhile, every time that the date indicator driving wheel 4 is substantially rotated by one rotation, at a constant timing (end of one day) in the one rotation of the date indicator driving wheel 4 , the date feeding finger 6 is engaged with the mostly proximate one of the teeth 10 on the downstream side and pushes the teeth 10 in D3 direction against the spring force of the spring portion 27 of the date jumper 20 . When the date indicator 8 is rotated in D3 direction by rotational toque in D3 direction around the rotational axis line C 1 applied to the teeth 10 , the jumping and restricting portion 23 is pivoted in E2 direction around the center axis line C 3 by a tooth 10 r on the downstream side in the pair of teeth 10 , 10 (that is, teeth 10 r and 10 f on the downstream side and the upstream side of FIG. 2). As a result, the date jumper 20 reaches a jumping position or a jumping and restricting position of FIG. 3 in accordance with rotation of the date indicator driving wheel 4 in D2 direction and rotation of the date indicator 8 in D3 direction. When the date jumper 20 slightly rides over the jumping and restricting position (jumping position), the date jumper 20 rotates the date indicator 8 by an amount of one pitch of the teeth 10 of the teeth portion 9 while being fitted to an interval between next pair of the teeth 10 , 10 in one motion by the spring force of the spring portion 27 in E1 direction to thereby advance date indication by one day. In rotating the date indicator 8 , the teeth 10 of the teeth portion 9 of the date indicator 8 leaves from the date feeding finger 6 of the date indicator driving wheel 4 and next ones of the teeth 10 on the downstream side reach a position at which the ones of the teeth 10 can engage with the date feeding finger 6 only after the date indicator 4 and the date feeding finger 6 make substantially another rotation.
[0037] In further details, in addition to FIG. 2 through FIG. 4, as is understood from FIG. 5, a thickness of the jumping and restricting finger portion 28 of the jumping and restricting portion 23 , that is, a length thereof in Z direction is larger than thicknesses or lengths in Z direction of the base portion 22 , the rigid shaft portion 24 and the spring portion 27 . Typically, the thicknesses of the shaft portion 24 and the spring portion 27 are about 0.2 mm and the thickness of the jumping and restricting portion 23 is about 0.5 mm. However, any of these portions may be thicker or thinner. Further, the jumping and restricting portion 23 is provided with an eaves-like flat plate portion 32 as a restricting portion projected frontward from the jumping faces or the engaging side faces 29 and 30 and the end portion 31 to have a main face substantially flush with a main face of the jumping and restricting finger portion 28 on a side proximate to the main plate 2 . In this case, the front direction signifies a direction in which corresponding teeth of the date indicator 8 are disposed, that is, in this example, an outer direction in a radius direction with respect to the center C 1 . Further, the eaves-like flat plate portion 32 may be provided on an upper side (front face side) instead of being provided on a lower side (back face side) or may be provided on two upper and lower sides.
[0038] Further, although a position of the rigid shaft portion 24 connected to the jumping and restricting portion 23 with regard to the thickness direction Z, is typically disposed at a center portion in Z direction of the jumping and restricting portion 23 as in the illustrated example, instead thereof, the position may be a position shifted in + or −Z direction or either of main faces of the jumping and restricting portion 23 on + or −Z side may be flush with the main face on + or −Z side of the rigid shaft portion 24 .
[0039] Therefore, even when respectives of the side faces 29 and 30 of the jumping and restricting finger portion 28 of the jumping and restricting portion 23 are engaged with corresponding ones of the teeth 10 , 10 as shown by FIG. 2, further, even when engagement between the side faces 29 and 30 of the jumping and restricting finger portion 28 of the jumping and restricting portion 23 and the teeth 10 , 10 of the teeth portion 9 is disengaged and the jumping and restricting end portion 31 of the jumping and restricting finger portion 28 rides over one of the teeth 10 along the front end 10 a of the one of the teeth 10 of the teeth portion 9 as shown by FIG. 3, since an inner side main face 33 of the eaves-like flat plate portion 32 is disposed proximately to an outer side main face 16 of the teeth portion 9 of the date indicator 8 , displacement or positional shift in −Z direction of the date indicator 8 relative to the jumping and restricting portion 23 is hampered by the eaves-like flat plate portion 32 of the jumping and restricting portion 23 . Further, although the eaves-like flat plate portion 32 is extended to the back side of the outer side face 16 of the center of one of the teeth 10 in jumping, the eaves-like flat plate portion 32 may be extended to a position opposed to an outer side face (end face disposed in −Z direction) of the contiguous teeth 10 , 10 on both sides of the upstream side and the downstream side (that is, both or either of teeth 10 r 1 and 10 f 1 , for example, one of the teeth 10 on the downstream side (that is, tooth 10 r 1 ).
[0040] Further, displacement or positional shit in +Z direction of the date indicator 8 relative to the jumping and restricting portion 23 , is restricted by a holding face 14 a of the date indicator holder 14 as is known from FIG. 4. Further, since the jumping and restricting portion 23 of the date jumper 20 is thicker than the rigid shaft portion 24 , the jumping and restricting finger portion 28 of the jumping and restricting portion 23 is brought into the notched portion 18 of the date indicator holder 14 in Z direction as described above. Therefore, even when the date indicator 8 is shifted in +Z direction relative to the jumping and restricting portion 23 to a maximum limit of being brought into contact with the inner face 14 a of the date indicator holder 14 , there is not a concern that engagement between the teeth portion 9 of the date indicator 8 and the jumping and restricting finger portion 28 of the jumping and restricting portion 23 is disengaged. Even in locking operation in which the jumping and restricting finger portion 28 of the jumping and restricting portion 23 of the date jumper 20 is engaged with at least one of the pair of contiguous ones of teeth 10 , 10 of the date indicator 8 (tooth disposed on the back side with regard to the rotational direction D3), or even in jumping operation or jumping and restricting operation in which the jumping and restricting finger portion 28 is brought into contact with the apex or the front end portion 10 a of one of the teeth 10 of the date indicator 8 , the condition remains unchanged and therefore, there is not a concern of releasing engagement between the teeth portion 9 of the date indicator 8 and the jumping and restricting finger portion 28 of the jumping and restricting portion 23 in all the positions of operating the date jumper 20 .
[0041] According to the date jumper 20 , the jumping and restricting portion 23 , that is, the jumping and restricting finger portion 28 and the eaves-like flat plate portion 32 are made of carbon nanofiber and mass thereof is small (in comparison with a case in which the jumping and restricting portion 23 is made of a metal material) and therefore, external force (inertia force) exerted to the watch by dropping the watch 1 can be restrained to a minimum. As a result, there is hardly a concern of causing a positional shift in the jumping and restricting portion 23 .
[0042] In addition, the jumping and restricting portion 23 , that is, the jumping and restricting finger portion 28 and the eaves-like flat plate portion 32 are made of carbon nanofiber and a frictional coefficient thereof is small and therefore, during a time period of all of the jumping and restricting operation of the date jumper 20 , frictional resistance of the jumping and restricting portion 23 of the date jumper 20 against rotation of the date indicator 8 in D2 direction can be restrained to be low and therefore, it is not necessary to apply excessive load for rotating the date indicator 8 .
[0043] Further, the spring portion 27 of the date jumper 20 is made of carbon nanofiber and therefore, even when the spring portion 27 is always applied with rotational torque or force in E2 direction, the spring portion 27 can exert elastic force in E1 direction without actually losing the spring performance or lowering the spring performance and continue exerting locking force to the jumping and restricting portion 23 in E1 direction around the rotational axis line C 3 .
[0044] Further, since the spring portion 27 of the date jumper 20 is made of carbon nanofiber, when the jumping and restricting portion 23 is pivoted in E1 and E2 directions, a supported portion 34 at a front end of “U” of the spring portion 27 in the U-like shape, can slidingly be moved pertinently in F1 and F2 directions relative to a spring receive portion 2 in a projected shape of the main plate 19 and therefore, a load state applied to the spring portion 27 can be varied regularly and periodically. As a result, according to the date jumper 20 , there is rarely a concern of dispersing a jumping and restricting state by the jumping and restricting portion 23 and energy consumption of a drive source can be restrained to a minimum. Further, the base portion 22 of the date jumper 22 is made of carbon nanofiber and a frictional coefficient thereof is small and therefore, frictional resistance between the base portion 22 and the shaft portion 15 is also small, the date jumper 20 can slidingly be rotated around the rotational axis line C 3 , there is rarely a concern of dispersing the jumping and restricting state by the jumping and restricting portion 23 and energy consumption of a drive source can be restrained to a minimum. Further, the date jumper 20 comprises an integrally molded product and therefore, the cost in assembling or the like can be restrained to a minimum.
[0045] Although according to the above-described, an explanation has been given of an example in which the date jumper 20 constituting the jumper structure is integrally provided with the base portion 22 , the-rigid shaft portion 24 , the jumping and restricting portion 23 and the spring portion 27 and rotatably fitted to the shaft portion 15 at the base portion 22 , so far as the jumping and restricting operation (locking and jumping and restricting (jumping) operation) can be made to be carried out at the jumping and restricting portion 23 by the spring portion 27 , the base portion and the shaft portion may be dispensed with, further, the date jumper 20 may be integrally formed with other member such as the main plate. That is, the date jumper 20 may be constructed by other constitution, for example, as follows.
[0046] (1) As described in FIG. 3 of Japanese Utility Model Publication No. 2183/1988 or in FIG. 3 of Japanese Utility Model Publication No. 164183/1981, a date jumper comprising a jumping and restricting portion and a spring portion may integrally be formed with a date indicator holder. In this case, according to the present invention, also the date indicator holder is mainly made of carbon nanofiber similar to the date jumper. Further, in this case, it is preferable to make a thickness of the jumping and restricting portion thicker than a thickness of the spring portion.
[0047] (2) As described in FIG. 3 of Japanese Utility Model Publication No. 164183/1981, a day jumper comprising a jumping and restricting portion and a spring portion may further be formed integrally with the date indicator holder. Further, also in this case, it is preferable to make the thickness of the jumping and restricting portion thicker than the thickness of the spring portion.
[0048] As described above, the date jumper 20 may be provided with any other shape and structure so far as the spring portion and the restricting portion are provided to provide a jumping and restricting function to the date indicator 8 . Further, the jumper structure may be other jumper such as a day jumper in place of the date jumper or may be used in a machine or an apparatus other than a watch. | To provide a jumper structure which is light-weighted and capable of reducing fabrication cost and a timepiece using the same. A jumper structure of a timepiece is constituted by integrally molding a jumping and restricting portion made of carbon nanofiber and a spring portion made of carbon nanofiber. A jumping and restricting portion of the jumper structure is thicker than the spring portion and the jumping and restricting portion includes a projected portion in a flat plate shape and in an eaves-like shape. | 6 |
FIELD OF THE INVENTION
[0001] The present invention generally relates to heat transfer devices that rely upon capillary action as a transport mechanism and, more particularly, to wicking materials for such devices.
BACKGROUND OF THE INVENTION
[0002] It has been suggested that a computer is a thermodynamic engine that sucks entropy out of data, turns that entropy into heat, and dumps the heat into the environment. The ability of prior art thermal management technology to get that waste heat out of semiconductor circuits and into the environment, at a reasonable cost, limits the density and clock speed of electronic systems.
[0003] A typical characteristic of heat transfer devices for electronic systems is that the atmosphere is the final heat sink of choice. Air cooling gives manufacturers access to the broadest market of applications. Another typical characteristic of heat transfer devices for electronics today is that the semiconductor chip thermally contacts a passive spreader or active thermal transport device, which conducts the heat from the chip to one of several types of fins. These fins convect heat to the atmosphere with natural or forced convection.
[0004] As the power to be dissipated from semiconductor devices increases with time, a problem arises: over time the thermal conductivity of the available materials becomes too low to conduct the heat from the semiconductor device to the fins with an acceptably low temperature drop. The thermal power density emerging from the semiconductor devices will be so high that copper, silver, or even gold based spreader technology will not be adequate.
[0005] One technology that has proven beneficial to this effort is the heat pipe. A heat pipe includes a sealed envelope that defines an internal chamber containing a capillary wick and a working fluid capable of having both a liquid phase and a vapor phase within a desired range of operating temperatures. When one portion of the chamber is exposed to relatively high temperature it functions as an evaporator section. The working fluid is vaporized in the evaporator section causing a slight pressure increase forcing the vapor to a relatively lower temperature section of the chamber, which functions as a condenser section. The vapor is condensed in the condenser section and returns through the capillary wick to the evaporator section by capillary pumping action. Because a heat pipe operates on the principle of phase changes rather than on the principles of conduction or convection, a heat pipe is theoretically capable of transferring heat at a much higher rate than conventional heat transfer systems. Consequently, heat pipes have been utilized to cool various types of high heat-producing apparatus, such as electronic equipment (See, e.g., U.S. Pat. Nos. 3,613,778; 4,046,190; 4,058,299; 4,109,709; 4,116,266; 4,118,756; 4,186,796; 4,231,423; 4,274,479; 4,366,526; 4,503,483; 4,697,205; 4,777,561; 4,880,052; 4,912,548; 4,921,041; 4,931,905; 4,982,274; 5,219,020; 5,253,702; 5,268,812; 5,283,729; 5,331,510; 5,333,470; 5,349,237; 5,409,055; 5,880,524; 5,884,693; 5,890,371; 6,055,297; 6,076,595; and 6,148,906).
[0006] The flow of the vapor and the capillary flow of liquid within the system are both produced by pressure gradients that are created by the interaction between naturally-occurring pressure differentials within the heat pipe. These pressure gradients eliminate the need for external pumping of the system liquid. In addition, the existence of liquid and vapor in equilibrium, under vacuum conditions, results in higher thermal efficiencies. In order to increase the efficiency of heat pipes, various wicking structures have been developed in the prior art to promote liquid transfer between the condenser and evaporator sections as well as to enhance the thermal transfer performance between the wick and its surroundings. They have included longitudinally disposed parallel grooves and the random scoring of the internal pipe surface. In addition, the prior art also discloses the use of a wick structure which is fixedly attached to the internal pipe wall. The compositions and geometries of these wicks have included, a uniform fine wire mesh and sintered metals. Sintered metal wicks generally comprise a mixture of metal particles that have been heated to a temperature sufficient to cause fusing or welding of adjacent particles at their respective points of contact. The sintered metal powder then forms a porous structure with capillary characteristics. Although sintered wicks have demonstrated adequate heat transfer characteristics in the prior art, the minute metal-to-metal fused interfaces between particles tend to constrict thermal energy conduction through the wick. This has limited the usefulness of sintered wicks in the art.
[0007] Prior art devices, while adequate for their intended purpose, suffer from the common deficiency, in that they do not fully realize the optimum inherent heat transfer potential available from a given heat pipe. To date, no one has devised a wick structure for a heat pipe, which is sufficiently simple to produce, and yet provides optimum heat transfer characteristics for the heat pipe in which it is utilized.
SUMMARY OF THE INVENTION
[0008] The present invention provides a capillary structure for a heat transfer device that comprises a plurality of particles joined together by a brazing compound such that fillets of the brazing compound are formed between adjacent ones of the plurality of particles. In this way, a network of capillary passageways are formed between the particles to aid in the transfer of working fluid by capillary action, while the plurality of fillets provide enhanced thermal conduction properties between the plurality of particles so as to greatly improve over all heat transfer efficiency of the device.
[0009] In one embodiment, a heat pipe is provided that includes a hermetically sealed and partially evacuated enclosure, where the enclosure has internal surfaces and is at least partially drenched with a two-phase vaporizable fluid. A wick is disposed on at least one of the internal surfaces of the enclosure. The wick advantageously comprises a plurality of particles joined together by a brazing compound such that fillets of the brazing compound are formed between adjacent ones of the plurality of particles so as to form a network of capillary passageways between the particles.
[0010] In a further embodiment of the present invention, a heat pipe is provided comprising a sealed and partially evacuated enclosure having an internal surface and a working fluid disposed within a portion of the enclosure. A grooved brazed wick is disposed upon the internal surface of the heat pipe. The grooved brazed wick comprises a plurality of individual particles which together yield an average particle diameter and a brazing compound such that fillets of the brazing compound are formed between adjacent ones of the plurality of particles. At least two lands are provided that are in fluid communication with one another through a particle layer disposed between the at least two lands wherein the particle layer comprises at least one dimension that is no more than about six average particle diameters wherein the particles in the particle layer are thermally engaged with one another by a plurality of the fillets.
[0011] A method is also provided for making a heat pipe wick on an inside surface of a heat pipe container comprising the steps of providing a slurry of metal particles that are mixed with a brazing compound. The metal particles have a first melting temperature and the brazing compound has a second melting temperature that is lower than the first melting temperature. At least a portion of the inside surface of the container is coated with the slurry, and dried to form a green wick. The green wick is then heated to a temperature that is no less than the second melting temperature and below the first melting temperature so that the brazing compound is drawn by capillary action toward adjacent ones of the metal particles so as to form heat-distribution fillets between the adjacent metal particles thereby to yield a brazed wick.
[0012] In an alternative embodiment of the method of the invention, a mandrel having a grooved contour and a plurality of recesses is positioned within a portion of a heat pipe container. A slurry of metal particles having an average particle diameter and that are mixed with a brazing compound is introduced into the container. The metal particles comprise a first melting temperature and the brazing compound comprises a second melting temperature that is lower than the first melting temperature. At least a portion of the inside surface of the container is coated with the slurry so that the slurry conforms to the grooved contour of the mandrel and forms a layer of slurry between adjacent grooves that comprises no more than about six average particle diameters. The slurry is then dried to form a green wick. The green wick is then heated to a temperature that is no less than the second melting temperature and below the first melting temperature so that the brazing compound is drawn by capillary action toward adjacent ones of the metal particles so as to form heat-distribution fillets between the adjacent metal particles thereby to yield a brazed wick.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] These and other features and advantages of the present invention will be more fully disclosed in, or rendered obvious by, the following detailed description of the preferred embodiments of the invention, which are to be considered together with the accompanying drawings wherein like numbers refer to like parts and further wherein:
[0014] FIG. 1 is an exploded perspective view of a typical heat pipe enclosure of the type used in connection with the present invention;
[0015] FIG. 2 is a perspective view of the heat pipe enclosure shown in FIG. 1 ;
[0016] FIG. 3 is a cross-sectional view of the heat pipe shown in FIG. 2 ;
[0017] FIG. 4 is a significantly enlarged cross-sectional view of a portion of a brazed wick formed in accordance with one embodiment of the present invention;
[0018] FIG. 5 is a broken-way perspective view that has been highly enlarged to clearly represent metal particles and fillets that comprise one embodiment of the present invention;
[0019] FIG. 6 is a highly enlarged view, similar to FIG. 5 , of an alternative embodiment of brazed wick formed in accordance with the present invention;
[0020] FIG. 7 is an exploded perspective view of a heat pipe enclosure having an alternative embodiment of brazed wick in accordance with the present invention;
[0021] FIG. 8 is a cross-sectional view, as taken along lines 8 - 8 in FIG. 7 ;
[0022] FIG. 9 is a further alternative embodiment of heat pipe enclosure formed in accordance with the present invention;
[0023] FIG. 10 is a cross-sectional view of the tubular heat pipe enclosure shown in FIG. 9 , as taken along lines 10 - 10 in FIG. 9 ;
[0024] FIG. 11 is a highly enlarged view of a portion of a brazed wick disposed on the wall of the heat pipe shown in FIG. 10 ;
[0025] FIG. 12 is a perspective cross-sectional view of a tower heat pipe having a brazed wick formed in accordance with the present invention;
[0026] FIG. 13 is a highly enlarged surface view of a brazed wick coating the anterior surfaces of the tower heat pipe shown in FIG. 12 ;
[0027] FIG. 14 is an alternative embodiment of tower heat pipe having grooved base wick formed in accordance with the present invention;
[0028] FIG. 15 is a highly enlarged surface view of a brazed wick formed in accordance with the present invention;
[0029] FIG. 16 is a broken-way cross-sectional view of the groove-wick shown in FIGS. 7, 8 , and 13 ;
[0030] FIG. 17 is a highly enlarged cross-sectional view of a portion of the groove brazed wick shown in FIGS. 7, 8 , 13 , and 15 ; and
[0031] FIG. 18 is an end view of a mandrel used in manufacturing a grooved brazed wick in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0032] This description of preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. The drawing figures are not necessarily to scale and certain features of the invention may be shown exaggerated in scale or in somewhat schematic form in the interest of clarity and conciseness. In the description, relative terms such as “horizontal,” “vertical,” “up,” “down,” “top” and “bottom” as well as derivatives thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing figure under discussion. These relative terms are for convenience of description and normally are not intended to require a particular orientation. Terms including “inwardly” versus “outwardly,” “longitudinal” versus “lateral” and the like are to be interpreted relative to one another or relative to an axis of elongation, or an axis or center of rotation, as appropriate. Terms concerning attachments, coupling and the like, such as “connected” and “interconnected,” refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship. In the claims, means-plus-function clauses are intended to cover the structures described, suggested, or rendered obvious by the written description or drawings for performing the recited function, including not only structural equivalents but also equivalent structures.
[0033] Referring to FIGS. 1-6 , the present invention comprises a wick structure for a heat pipe or heat spreader 2 , hereinafter referred to as simply a heat pipe. Such heat pipes 2 are often sized and shaped to transfer and/or spread the thermal energy generated by at least one thermal energy source, e.g., a semiconductor device (not shown), that is thermally engaged between a portion of the heat pipe and a heat sink (not shown). Heat pipes 2 generally comprise a hermetically sealed enclosure such as a flat, hollow plate-like structure ( FIG. 2 ) or a tubular structure ( FIGS. 9, 12 and 14 ). Regardless of outer profile, each enclosure structure defines an evaporator section 5 , a condenser section 7 , and an internal void space or vapor chamber 10 . For example, in a planar rectangular heat pipe 2 , vapor chamber 10 is defined between a bottom wall 12 and a top wall 14 . In a tubular or tower heat pipe 2 , vapor chamber 10 extends longitudinally from one end of the tube to the other ( FIGS. 9, 12 , and 14 ).
[0034] In one preferred embodiment of a rectilinear enclosure, bottom wall 12 and a top wall 14 comprise substantially uniform thickness sheets of a thermally conductive material, e.g., copper, steel, aluminum, or any of their respective alloys, and are spaced-apart by about 2.0 (mm) to about 4.0 (mm) so as to form vapor chamber 10 within heat pipe 2 . Top wall 14 of heat pipe 2 is often substantially planar, and is complementary in shape to bottom wall 12 . Bottom wall 12 preferably comprises a substantially planer inner surface 18 and a peripheral edge wall 20 . Peripheral edge wall 20 projects outwardly from the peripheral edge of inner surface 18 so as to circumscribe inner surface 18 . Vapor chamber 10 is created within heat pipe 2 by the attachment of bottom wall 12 and a top wall 14 , along their common edges which are then hermetically sealed at their joining interface 24 . A vaporizable fluid (e.g., water, ammonia or freon not shown) resides within vapor chamber 10 , and serves as the working fluid for heat pipe 2 . For example, heat pipe 2 may be made of copper or copper silicon carbide with water, ammonia, or freon generally chosen as the working fluid. Heat pipe 2 is completed by drawing a partial vacuum within the vapor chamber after injecting the working fluid just prior to final hermetic sealing of the common edges of bottom wall 12 and the top wall 14 .
[0035] Referring to FIGS. 3-6 , in order for heat pipe operation to be initiated within the enclosure of heat pipe 2 , a capillary must be present within vapor chamber 10 that will pump condensed liquid from condenser section 7 back to evaporator sections, substantially unaided by gravity. In the present invention, a brazed wick 25 is located on inner surface 18 which defines the boundaries of vapor chamber 10 . Brazed wick 25 comprises a plurality of metal particles 27 combined with a filler metal or combination of metals that is often referred to as a “braze” or brazing compound 30 . It will be understood that “brazing” is the joining of metals through the use of heat and a filler metal, i.e., brazing compound 30 . Brazing compound 30 very often comprises a melting temperature that is above 450° C.-1000° C. but below the melting point of metal particles 27 that are being joined to form brazed wick 25 .
[0036] In general, to form brazed wick 25 according to the present invention, a plurality of metal particles 27 and brazing compound 30 are heated together to a brazing temperature that melts brazing compound 30 , but does not melt plurality of metal particles 27 . Significantly, during brazing metal particles 27 are not fused together as with sintering, but instead are joined together by creating a metallurgical bond between brazing compound 30 and the surfaces of adjacent metal particles 27 through the creation of fillets of re-solidified brazing compound (identified by reference numeral 33 in FIGS. 5 and 6 ). Advantageously, the principle by which brazing compound 30 is drawn through the porous mixture of metal particles 27 to create fillets 33 is “capillary action”, i.e., the movement of a liquid within the spaces of a porous material due to the inherent attraction of molecules to each other on a liquid's surface. Thus, as brazing compound 30 liquefies, the molecules of molten brazing metals attract one another as the surface tension between the molten braze and the surfaces of individual metal particles 27 tend to draw the molten braze toward each location where adjacent metal particles 27 are in contact with one another. Fillets 33 are formed at each such location as the molten braze metals re-solidify.
[0037] In the present invention, brazing compound 30 and fillets 33 create a higher thermal conductivity wick than, e.g., sintering or fusing techniques. This higher thermal conductivity wick directly improves the thermal conductance of the heat transfer device in which it is formed, e.g., heat pipe, loop heat pipe, etc. Depending upon the regime of heat flux that evaporator 5 is subjected to, the conductance of brazed wick 25 has been found to increase between directly proportional to and the square root of the thermal conductivity increase. Importantly, material components of brazing compound 30 must be selected so as not to introduce chemical incompatibility into the materials system comprising heat pipe 2 .
[0038] Metal particles 27 may be selected from any of the materials having high thermal conductivity, that are suitable for fabrication into brazed porous structures, e.g., carbon, tungsten, copper, aluminum, magnesium, nickel, gold, silver, aluminum oxide, beryllium oxide, or the like, and may comprise either substantially spherical, oblate or prolate spheroids, ellipsoid, or less preferably, arbitrary or regular polygonal, or filament-shaped particles of varying cross-sectional shape. For example, when metal particles 27 are formed from copper spheres ( FIG. 5 ) or oblate spheroids ( FIG. 6 ) whose melting point is about 1083° C., the overall wick brazing temperature for heat pipe 2 will be about 1000° C. By varying the percentage brazing compound 30 within the mix of metal particles 27 or, by using a more “sluggish” alloy for brazing compound 30 , a wide range of heat-conduction characteristics may be provided between metal particles 27 and fillets 33 .
[0039] For example, in a copper/water heat pipe, any ratio of copper/gold braze could be used, although brazes with more gold are more expensive. A satisfactory combination for brazing compound 30 has been found to be about six percent (6)% by weight of a finely divided (−325 mesh), 65%/35% copper/gold brazing compound, that has been well mixed with the copper powder (metal particles 27 ). More or less braze is also possible, although too little braze reduces the thermal conductivity of brazed wick 25 , while too much braze will start to fill the wick pores with solidified braze metal. One optimal range has been found to be between about 2% and about 10% braze compound, depending upon the braze recipe used. When employing copper powder as metal particles 27 , a preferred shape of particle is spherical or spheroidal. Metal particles 27 should often be coarser than about 200 mesh, but finer than about 20 mesh. Finer wick powder particles often require use of a finer braze powder particle. The braze powder of brazing compound 30 should often be several times smaller in size than metal particles 27 so as to create a uniformly brazed wick 25 with uniform properties.
[0040] Other brazes can also be used for brazing copper wicks, including nickelnickel-based Nicrobrazes, silver/copper brazes, tin/silver, lead/tin, and even polymers. The invention is also not limited to copper/water heat pipes. For example, aluminum and magnesium porous brazed wicks can be produced by using a braze that is an aluminum/magnesium intermetallic alloy.
[0041] Brazing compound 30 should often be well distributed over each metal particle surface. This distribution of brazing compound 30 may be accomplished by mixing brazing compound 30 with an organic liquid binder, e.g., ethyl cellulose, that creates an adhesive quality on the surface of each metal particle 27 (i.e., the surface of each sphere or spheroid of metal) for brazing compound 30 to adhere to. In one embodiment of the invention, one and two tenths grams by weight of copper powder (metal particles 27 ) is mixed with two drops from an eye dropper of an organic liquid binder, e.g., ISOBUTYL METHACRYLATE LACQUER to create an adhesive quality on the surface of each metal particle 27 (i.e., the surface of each sphere or spheroid of metal) for braze compound 30 to adhere to. A finely divided (e.g., −325 mesh) of braze compound 30 is mixed into the liquid binder coated copper powder particles 27 and allowed to thoroughly air dry. About 0.072 grams, about 6% by weight of copper/gold in a ratio of 65%/35% copper/gold brazing compound, has been found to provide adequate results. The foregoing mixture of metal particles 27 and brazing compound 30 are applied to the internal surfaces of heat pipe 2 , for example inner surface 18 of bottom wall 12 , and heated evenly so that brazing compound 30 is melted by heating metal particles 27 . Molten brazing compound 30 that is drawn by capillary action, forms fillets 33 as it solidifies within the mixture of metal particles 27 . For example, vacuum brazing or hydrogen brazing at about 1020° C. for between two and eight minutes, and preferably about five minutes, has been found to provide adequate fillet formation within a brazed wick. A vacuum of at least 10 −5 torr or lower has been found to be sufficient, and if hydrogen furnaces are to be used, the hydrogen furnace should use wet hydrogen. In one embodiment, the assembly is vacuum fired at 1020° C. for 5 minutes, in a vacuum of is 5×10 −5 torr or lower.
[0042] Referring to FIGS. 7, 8 , 14 , and 16 - 17 , grooved brazed wick structure 38 may also be advantageously formed from metal particles 27 combined with brazing compound 30 . More particularly, a mandrel 40 ( FIG. 18 ) is used to create grooved wick structure 38 that comprises a plurality of parallel lands 45 that are spaced apart by parallel grooves 47 . Lands 45 of mandrel 40 form grooves 50 of finished brazed grooved wick structure 38 , and grooves 47 of mandrel 40 form lands 52 finished brazed grooved wick structure 38 . Each land 52 is formed as an inverted, substantially “V”-shaped or pyramidal protrusion having sloped side walls 54 a , 54 b , and is spaced-apart from adjacent lands. Grooves 50 separate lands 52 and are arranged in substantially parallel, longitudinally (or transversely) oriented rows that extend at least through evaporator section 5 . The terminal portions of grooves 50 , adjacent to, e.g., a peripheral edge wall 20 , may be unbounded by further porous structures. In one embodiment, a relatively thin layer of brazed metal particles is deposited upon inner surface 18 of bottom wall 12 so as to form a groove-wick 55 at the bottom of each groove 50 and between spaced-apart lands 52 . For example, brazed copper powder particles 27 are deposited between lands 52 such that groove-wick 55 comprises an average thickness of about one to six average copper particle diameters (approximately 0.005 millimeters to 0.5 millimeters, preferably, in the range from about 0.05 millimeters to about 0.25 millimeters) when deposited over substantially all of inner surface 18 of bottom wall 12 , and between sloped side walls 54 a , 54 b of lands 52 . Advantageously, metal particles 27 in groove-wick 55 are thermally and mechanically engaged with one another by a plurality of fillets 33 ( FIG. 17 ). When forming grooved brazed wick structure 38 , inner surface 18 of bottom wall 12 (often a copper surface) is lightly coated with organic binder ISOBUTYL METHACRYLATE LACQUER and the surface is “sprinkle coated” with braze compound copper/gold in a ratio of 65%/35%, with the excess shaken off. Between 1.250 and 1.300 grams (often about 1.272 grams) of braze coated copper powder 27 is then placed on the braze coated copper surface and mandrel 40 is placed on top to form a grooved brazed wick structure 38 .
[0043] Significantly groove-wick 55 is formed so as to be thin enough that the conduction delta-T is small enough to prevent boiling from initiating at the interface between inner surface 18 of bottom wall 12 and the brazed powder forming the wick. The formation of fillets 33 further enhances the thermal conductance of groove-wick 55 . Groove-wick 55 is an extremely thin wick structure that is fed liquid by spaced lands 52 which provide the required cross-sectional area to maintain effective working fluid flow. In cross-section, groove-wick 55 comprises an optimum design when it comprises the largest possible (limited by capillary limitations) flat area between lands 52 . This area should have a thickness of, e.g., only one to six copper powder particles. The thinner groove-wick 55 is, the better performance within realistic fabrication constraints, as long as the surface area of inner surface 18 has at least one layer of copper particles that are thermally and mechanically joined together by a plurality of fillets 33 . This thin wick area takes advantage of the enhanced evaporative surface area of the groove-wick layer, by limiting the thickness of groove-wick 55 to no more than a few powder particles while at the same time having a significantly increased thermal conductance due to the presence of fillets 33 joining metal particle 27 . This structure has been found to circumvent the thermal conduction limitations associated with the prior art.
[0044] It is to be understood that the present invention is by no means limited only to the particular constructions herein disclosed and shown in the drawings, but also comprises any modifications or equivalents within the scope of the claims. | A capillary structure for a heat transfer device, such as a heat pipe is provided having a plurality of particles joined together by a brazing compound such that fillets of the brazing compound are formed between adjacent ones of the plurality of particles. In this way, a network of capillary passageways are formed between the particles to aid in the transfer of working fluid by capillary action, while the plurality of fillets. provide enhanced thermal transfer properties between the plurality of particles so as to greatly improve over all heat transfer efficiency of the device. A method of making the capillary structure according to the invention is also presented. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to sheet handling and particularly to the conveying of paper sheets between two portions of a duplicating system. This may be between a first printing head and a second printing head or between a printing head and another device, such as a collator.
It has been discovered that much operator efficiency can be obtained by arranging certain paper paths in a duplicating system at angles to each other as explained in my copending application Ser. No. 600,992 entitled HIGH OPERATOR EFFICIENCY DUPLICATING SYSTEM. The angle is normally 90°, although some variation from this up to about 20° in either direction can normally be accomodated if required.
In order to do this, the paper sheets must be handled at high speeds, and in a duplicating environment they inherently travel in close array, often in the range of 5000 to 10,000 sheets per hour with an intersheet spacing of 1 to 16 inches. To accomplish path direction changes at this speed and spacing without interference between sheets in the stream is recognized as extremely difficult.
While the present invention is described mainly in terms of a lithographic duplicator, it will be understood that its principles are applicable to any type of printer or duplicator, such, for example, as high-speed electrophotographic equipment, and when the terms "printer," "duplicator" and "duplicating system" are used hereinafter, all types of reprographic equipment are embraced.
SUMMARY OF THE INVENTION
I have discovered that by feeding the sheets from a source (such as a printing head) on a first conveyor whose terminus is slightly higher than the surface of a special second conveyor, positioned at an angle to the first conveyor, the requisite speed of transfer can be achieved.
The second conveyor requires special properties to receive each sheet smoothly by gravity from the first conveyor and convey it away reliably once received. These properties are provided by a second conveyor consisting of a series of parallel rollers of relatively large diameter and closely spaced, with their axes extending generally parallel to the first path and generally normal to the second, the rollers of the second conveyor being power driven at the sheet conveyance speed required by the duplicator.
There are also provided means for quickly establishing and maintaining driving contact between the rollers and the sheet, while at the same time minimizing the possibility of ink set-off to the machine parts in case the duplicator is of the wet ink variety, and stop means for aligning the sheet with the new path, against which aligning means the sheet is urged by a slight cant to the rollers.
Means are also provided for maintaining a general or partial control over the flying sheets during the transfer operation.
Because it may be desirable to have the sheet carried away from the first path in either one direction or the other, the second conveyor is so designed that the means for providing the roller cant to drive the sheet against the aligning stop includes a novel arrangement which allows the conveyor to be built of either hand without significant differences in the parts used.
DISCUSSION OF THE PRIOR ART
The only construction of which I am presently aware, which has significant pertinence to the present situation, is an arrangement embodied in a sheet folder manufactured by Roneo Vickers Hadawe, Ltd. A first folding head folds a paper sheet once or twice, and this folded sheet is fed to a roller conveyor running at an angle to the path of sheets issuing from the first folding head. The folded sheets are carried thereby to a second folding head where a fold normal to the first fold or folds can be made.
The roller conveyor embodied in this organization is dealing with a situation distinct from that presently under consideration in that the articles being transferred are, in fact, fairly rigid objects by reason of the fold or folds having been formed therein. The rollers of the conveyor are rubber covered, are perhaps 0.625 inches in diameter, and are placed on about 2-1/2 inch centers so as to be roughly 2 inches apart at their points of nearest approach. As disclosed by the Roneo Vickers Hadawe construction there is no implication that broad flexible paper sheets issuing from a duplicator could receive a successful high-speed direction change by way of such a roller conveyor.
In particular, the folded sheet issuing from the first folding head in the prior art device is speeded up, especially on the roller conveyor, to a point such that the sheet on the conveyor is well out of the way when the next folded sheet is presented. This is feasible because the folded sheets can withstand much more force than unfolded sheets when striking a fixed stop.
In a duplicator situation, where there is not only the register stop on the roller conveyor but also either a register stop on a second printing head or the pocket walls on a sheet distributor, as in the present invention, the normal weight, single thickness sheet of paper being handled must approach any such stop surface at no more than a predetermined limiting speed to avoid mutilating the edge.
This surface speed limitation would be inconsistent with the concept, present in the Roneo Vickers Hadawe equipment, of moving the sheets around the corner without overlap at the turning point, and hence renders the use of the roller conveyor aspect of that equipment apparently unsuitable for duplicator applications.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawing:
FIG. 1 is a plan of a duplicating system employing the present invention and embodying a first conveyor and a second conveyor;
FIGS. 2a to 2d are fragmentary, somewhat schematic plan views illustrating the operation of the invention and showing the sheets in four progressive positions separated by short sequential time intervals;
FIG. 3 is a top plan to a larger scale, with parts broken away, of the second conveyor including the means for generally controlling motion of the flying sheets;
FIG. 4 is a longitudinal section of the device of FIG. 3, taken substantially on line 4--4 of FIG. 3 with parts broken away; and
FIG. 5 is an end elevation of the device of FIG. 2, also including a fragmentary showing of the first conveyor in side elevation.
In the plan view of FIG. 1 can be seen a duplicating system 10 which in the form shown is a MULTILITH Model 2850 lithographic offset duplicator 12, to which is connected a master maker 14 for preparing lithographic masters from original documents by the electrostatic process in a known manner.
As the copy sheets exit from the printing couple of the duplicator 12, they are transported away by a first conveyor shown as a belt conveyor 16.
Just beyond the end of the belt conveyor 16 is a second conveyor 18 which accepts sheets from the belt conveyor and moves them in a direction substantially normal to their original direction and presents them to a collator 20 which is shown as being of the rotary drum type.
As explained in my copending application Ser. No. 600,992, filed Aug. 1, 1975 there are certain distinct advantages in placing the sheet travel paths of the duplicator and the collator substantially normal to each other, concerned generally with operator convenience leading to higher productivity by the operator of the duplicating system.
One of the perceived difficulties in attempting to implement this principle, however, was the high speed at which copy sheets issue from a modern lithographic duplicator as well as other types of duplicators; i.e., on the order of 7500 to 10,000 copies per hour with, in some cases, very little space between copies. Trying to redirect these copy sheets in a path substantially normal to the path on which they issue initially has not been deemed feasible on an economic basis because of the high risk of interference and jams at the redirection location.
To be sure, manipulation of the sheets to gain wider separation and better individual control is mechanically feasible, but such constructions involve not only equipment expense, but require substantial additional floor area which is usually an unacceptable feature from the standpoint of the customer's space requirements.
According to the present invention it has been discovered that a particular configuration of conveyor, when adopted for use at the second conveyor location (i.e., conveyor 18) solves the foregoing enigma and makes possible the change of sheet direction in a practical and economic manner without increasing the danger of sheet jams on the one hand, while still satisfying the important and practical economic and space requirement restrictions on the other.
This conveyor is shown in detail in FIGS. 3, 4 and 5, and comprises a frame including side channels 50 and 52 connected by a bottom plate 54. Slideways 56 and 58 are mounted on the inner surfaces of the channels 50 and 52 respectively.
A series of identical bearing blocks 60 are mounted in the slideways and fastened therein by end stops such as 62. Each block has a bore 64 (FIGS. 3 and 5) which serves as a bearing to receive the journal of a roller, the axis of which extends at a slight angle to the direction normal to the longitudinal axis of the conveyor frame, in this case at an angle of about 10°. Each bore 64 is in alignment with a corresponding bore of another bearing block 64 on the opposite side of the frame and each corresponding pair supports between them for free rotation a roller 66 whose journals 68 are received in the bores 64.
At each end of the conveyor frame at its upper surface there is mounted a guide plate with one angled edge (see plates 70 and 72) matching the roller angle, which plates act as support surfaces for sheets and lie substantially in a plane which is the common tangent to the upper elements of the roller surfaces to support the sheets at either end of the roller system as they approach or depart.
In the preferred form shown, the rollers are about two inches in diameter and they are placed on about 2-1/2 inch centers so that, at points of closest approach, their surfaces are about 1/2 inch apart. In carrying out the present invention it is found that the roller diameters should be between about 1/2 inch and 3 inches in diameter, with the space between roller surfaces no more than about one-fourth of the roller diameter in order to insure successful performance. Space and weight considerations would tend to suggest use of rollers of smaller diameter, while cost and manufacturing consideration would suggest the use of fewer rollers of larger diameter. The optimum for most purposes, therefore, appears to be the preferred form shown, wherein nine rollers are found to perform acceptably for sheets of the usual sizes. For the purposes of the present discussion the expression "closely spaced rollers" will be understood to indicate an assembly in which the roller spacing and roller diameters are in the ratio above-indicated or a smaller ratio, and this language will be so interpreted wherever used herein.
The surfaces of rollers 66 are of metal and preferably are chrome-plated so as to resist transfer of ink, since sheets exiting from a duplicator may have printing on the lower face as well as the upper, and if the ink had not entirely dried, light line contact between the roller surface, when plated as described, offers only miniscule chance for smudging or offset.
The rollers 66 are powered by a friction belt 73 which runs beneath the rollers, the belt being trained around end pulleys 74,76, and over intermediate pulleys 78 which project upward between adjacent rollers 66 to provide a certain amount of driving wrap of the belt thereagainst. All of the rollers 74, 76 and 78 are supported for rotation on bearing ears such as 80 (FIG. 5) formed on a channel 82 secured to the bottom member 54 of the frame. The belt 73 is preferably of somewhat resilient material so as to remain taut and thereby maintain driving tension at all times.
The pulley 74 may be driven in any suitable manner, either by an individual electric motor or, as shown in the present drawing, by a drive connection from the power source within the collator 20. This is accomplished, as seen in FIG. 3, by a belt 83 which is driven from a shaft 84 which forms a part of the collator and receives its power therefrom. The belt 83 is trained over pulley 86 on the shaft 84 and over an idler 88, to drive a pulley 90 connected with a stub shaft 92 which has a driving connection with a shaft 94 associated with pulley 74 through any simple angle drive connection, for example, the relatively stiff but still somewhat flexible sleeve 96.
The drive ratios are so selected that the surface speed of the rollers 66 is at least equal to that of the conveyor 16 on a sheet frequency basis. That is to say, the same number of sheets per unit time will be independently forwarded in a stream of spaced sheets as were forwarded by the conveyor 16. It will be understood that if the sheets are first fed lengthwise on conveyor 16, and then long edge foremost on conveyor 18, or if there is substantial spacing between sheets initially, it is possible that the spacing between sheets may be allowed to collapse somewhat, and that the conveyor 18 may operate at a slightly slower surface speed than conveyor 16. However, on a sheet frequency basis they must, of course, be equal and for practical purposes it is usually preferable to have the rollers 66 travel at a surface speed at least equal to that of the conveyor 16, and more generally at a somewhat higher surface speed.
It is important to note, however, that the speed of the sheets emerging from the belt conveyor 16 must not exceed a certain value depending on the type of paper being fed, in order that the sheet edges shall not be mutilated as they strike the register guide and aligning stop 126 which will be presently described in detail. For sheets of ordinary weight, say 20 pound bond, this value is perhaps 350 ft. per minute. This maximum value of sheet speed is referred to hereinafter as the limiting stop engagement speed and is determinable by test for any particular paper. A safe value for most sheets would probably be about 275 ft/min which may be called the nominal limiting stop engagement speed for general purpose machines. Machines handling sheet stock in a restricted weight range would, of course, be compatible with a different readily determinable value of nominal limiting stop engagement speed. While the surface speed of the rollers 66 can exceed this speed somewhat, consideration must be had for the fact that the sheet will be passing directly into a feed-in conveyor of a sheet distributing device 20 so that the speed of the rollers 66 of the roller conveyor 18 must be kept within a range such that the change or slowdown to at least the limiting stop engagement speed will not be too drastic and hence introduce a further possible jam inducing situation.
An important feature of my invention is the construction of the second conveyor 18 using the individual canted bearing blocks 60 previously described. As seen in FIG. 1, the sheet makes a left turn as it emerges from the duplicator. If it is desired to have the sheet make a right turn, the 10° angle of the roller axes away from the initial path direction, would need to be reversed in order to properly urge the sheet against the register stop. With my construction this can be readily taken care of during construction with minimum change of conveyor design, by merely repositioning the slideways 56 at the proper location on the interior of the channels 50, 52, and then inverting the bearing blocks 60 as they are placed into the channels so as to give an opposite cant to the rollers, plus changing the angle of the channel 82, and adjusting the locations of the scaffold supported elements to be presently described. Thus, a conveyor of opposite hand can be constructed very readily with only the most nominal changes in design.
As illustrated in FIG. 5, the relationship of the first conveyor 16 and the second conveyor 18 is such that the exit point of conveyor 16 is substantially flush with the ends of rollers 66 and a short distance (e.g., between 1 and 2 inches) above their uppermost elements.
It can be seen from FIG. 5 that, as the sheet being transferred from one conveyor to the other is making the transition, it is temporarily in a flying condition and not under strict control. In order to meet this situation, the apparatus according to the present invention embodies several instrumentalities to be presently described.
To carry and properly position these instrumentalities, there is provided supporting scaffolding including two uprights 98 affixed to the side channel 50, and two uprights 100 affixed to the side channel 52 of the frame.
Between uprights 100 is mounted a horizontal beam 102, and the latter supports collars 104. Between the top of each upright 98 and each collar 104 there is swung a horizontal beam 106, and collars 104 being so set on beam 102 that the beams 106 are parallel to the axes of rollers 66.
The purpose of the two beams 106 is to support a chute-forming guide plate and register guide 108, and the latter has attached thereto a pair of support connections 110. Each such connection includes a block 112 with an upwardly projecting screw 114 and a pair of upwardly projecting guide pins 116. The guide pins are slidably received in matching openings in an upper block 118 slidable on the beam 106. This upper block also carries a captive nut 120 which threadedly receives the screw 114 and serves to adjust the height of the chute above the rollers 66. A clamp screw 122 (FIG. 3) retains the block in desired position on its beam 106, and allows adjustment of the register guide laterally of the conveyor 18.
As can be seen in FIG. 5, one margin 124 of the guide plate 108 is flared upwardly to form with the roller surfaces the receiving mouth of a chute for funneling the lead edge of an incoming sheet to the proper location. The opposite margin of member 108 is turned downardly as indicated at 126 to form a stop surface for registering the sheet and orienting it in the proper direction, and is referred to herein as a "register guide" or "aligning stop." The lower edge of the margin 126 is configured to conform generally to the surfaces of rollers 66 as seen in FIG. 4.
Adjacent the register guide 126, the member 108 is provided with a series of openings which are slightly smaller in diameter than balls 128 which rest therein. The balls are preferably of steel or other material of substantial density, are preferably of stainless steel or are chrome-plated to resist ink offset, and are positioned one above each roller 66 to urge the margin of a sheet by gravity into driving contact with the underlying roller. A retainer bar 130 prevents the balls from becoming dislodged from their openings. It can be seen that the balls 128 simultaneously provide for two separate functions. They constitute, in effect, a means cooperating with the roller surfaces for both readily accepting a sheet between themselves and the roller surfaces when the sheet is thus projected by the first conveyor, and for establishing instantaneous driving connection between such interposed sheet and the roller surface for moving the sheet promptly along the second conveyor. By reason of their point contact and freedom to roll in any direction, as well as their direct cooperation with a curved roller surface, and the above-noted material of the ball surface, these balls contribute importantly to the ability of the equipment to handle sheets recently printed with wet ink under conditions such that offset of ink to the conveyor parts is prevented or drastically minimized.
To lead a flying sheet into the mouth of the chute formed by the guide plate 108 and the upper surfaces of the rollers 66 (see FIG. 5), there are provided two sheet deflectors 132, each adjustably positionable on the beam 102 by means of its connecting clamp 134.
The immediately foregoing description identifies the means for partially controlling a sheet as it leaves the first conveyor and arrives at the second. As seen in FIG. 5, the sheet moves from the left and has its lead edge properly directed by the sheet deflectors 132 in a slightly downwardly direction so as to be presented beneath the lip of the guide plate 108, which then continues its guidance until the lead edge strikes the aligning stop 126 with the adjacent margin underlying the balls 128 in driving contact with the surface of rollers 66, whereby the sheet propulsion in the new direction is promptly initiated.
As the sheet starts to move along the second conveyor (away from the viewer in FIG. 5 and towards the left in FIG. 3), the portion last arriving may still be elevated somewhat out of contact with the roller surfaces, and to insure prompt contact there is provided a second set of sheet deflectors 136. These may be either cantilevered bars similar to the deflectors 132, or flexible metal straps with their free ends resting lightly by gravity on the surfaces of rollers 66. In any case they are mounted by means of connecting clamps 138 on a cantilevered beam 140 adjustably affixed to the beam 102 by a mounting clamp 142. These sheet deflectors rapidly funnel the new lead edge of the sheet promptly into contact with the roller surfaces and hold the passing sheet in such contact as it moves towards the left in FIG. 3.
STATEMENT OF OPERATION
Referring particularly to FIGS. 1 and 3, it will be seen that the sheets in FIG. 1, will issue rapidly towards the left from the duplicator 12. For the sake of this discussion it will be assumed that the duplicator is producing 8-1/2 × 11 sheets at a rate of 7500 per hour with about a 3-inch interval between sheets.
The stream of sheets proceeds along the conveyor 16 at a rate of approximately 2-1/2 feet per second, and each in turn is thrust onto the conveyor 18. At this point it is quickly funneled into contact with the surfaces of rollers 66 where its margin is held by the balls 128, whereupon the sheet instantaneously begins its travel along the conveyor 18 (downwardly in FIG. 1). The sheet may not be instantaneously aligned with the conveyor 18 as it arrives since it must fly from one conveyor to the other, but the cant of the rollers 66 forces the sheet against the register guide 126 to straighten it out in a very short travel distance of an inch or two. As described above, the sheet, now moving along conveyor 18, is promptly forced against the rollers by the second set of sheet deflectors 136. These latter deflectors, while not essential, provide additional control for the sheet and are presently deemed desirable additions.
It can be readily seen that at the speeds and spacing imposed by the duplicator function and the sensitive character of the sheets being handled, unacceptable interference between adjacent sheets at the conveyor junction seems inevitable. In spite of this obvious barrier to success, I determined by a series of experiments that with the arrangement above described the sheets could be made to pass each other without interference and with the utmost reliability in spite of a significant overlap as they pass each other. This interaction of the sheets as they make the change in path direction can be seen approximately in FIGS. 2a - 2d which show the progression at very short intervals.
FIG. 2a (occurring at time T) shows the sheet position just as the first sheet reaches the register guide 126 (diagrammatically indicated). A moment later (say at time T + 0.13 sec.), FIG. 2b shows the second sheet having moved partially over the first sheet, while the first sheet has straightened itself against the register guide 126. FIG. 2c illustrates the situation at approximately time T + 0.22 sec. with the sheets still overlapping, and FIG. 2d illustrates the situation at about time T + 0.26 sec. when the first and second sheets have just cleared. This transition is repeated over and over with each succeeding pair of sheets, and with the utmost reliability, making possible the path direction change in a very restricted compass without exceeding acceptable sheet speeds.
As will be seen from the foregoing description, the problems solved by this invention relate mainly to the speed and spacing at which the sheets are being handled. It is generally above the sheet frequency of 5000 sheets per hour that the problems of moving thin paper sheets in an angular path arise, and especially where the path length between the turn and the next sheet stop must be short. In the present instance, this latter distance is about 3 to 4 feet. As previously explained, a nominal limiting stop engagement speed is a recognized limitation from the standpoint of prevention of sheet edge mutilation when encountering stops. However, to insure sheets traveling at normal spacing intervals around a corner without overlap, sheet speeds in excess of this are always required. Rapid acceleration and deceleration of sheets as well as manipulation and guiding of sheets above nominal limiting stop engagement speed are conditions which contribute materially to interruptions and jams and are hence to be avoided in any way possible. By means of the particular conveyor arrangement described herein with closely spaced rollers fed from above, I have discovered that overlap at the turn can be tolerated even at high rates of sheet frequency, and that conflict and jams do not ensue, thereby allowing sheet feed speeds in feet per minute to be held within effective limits. | A conveyor is provided for accepting sheets moving in one direction from a duplicator and conveying them at an angle to the initial direction; e.g., 90°. The conveyor consists of rollers of relatively large diameter arranged with close spacing so that sheets of paper will pass easily from one to the other, and entering sheets will find fairly continuous support whatever their size. The rollers are set at an angle to the desired feed path to provide an effect urging the sheets towards a side alignment stop and the construction is such that the angular roller setting may be readily made during manufacture, to act towards whichever side of the feed path is selected as the one to carry the alignment stop surface. Means are provided for controlling the sheets during transfer from one conveyor to the other, and for instantaneous acceleration in the second direction by the roller conveyor, permitting handling of closely spaced sheets at high sheet frequency without danger of interference between adjacent sheets which might result in jamming. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to improvements in video circuit and video signal processing and control techniques, and more particularly to improvements in video amplifier and preamplifier circuits and signal processing and control techniques that control, reduce, or eliminate the "tilt" of a video display, and to such circuits that may be realized with LinBiCMOS circuits.
2. Relevant Background
"Tilt" is a phenomenon in color monitors in which the height of the picture on one side, generally the top and bottom edges on the right side, is less than the height of the picture on the other side. This results in the picture being displayed with a slightly trapezoidal shape, with increasing triangular black top and bottom margins. Although in many cases, the tilt is hardly noticeable, in other cases, the tilt may be sufficiently large as to be objectionable to the user.
Tilt may be caused by leakage of one or more of the transistors of the video preamplifier circuit. The video preamplifier circuit provides an output signal that defines the location that the scanning beam is to occupy on the display screen by predefining the scanning or drive voltage magnitude. However, due however to leakage across one or more DC level holding transistors, typically due to thermal effects, especially from the base of bipolar transistors, the DC voltage magnitude may not be completely maintained over the scanning time for each scan line. The result is that the display beam does not hold an exactly horizontal scan line, creating the tilt phenomenon described above.
SUMMARY OF THE INVENTION
In light of the above, therefore, it is an object of the invention to provide an improved video preamplifier circuit.
It is another object of the invention to provide a video preamplifier circuit of the type described that has reduced or eliminated "tilt" phenomenon.
It is yet another object of the invention to provide an improved method for reducing or eliminating the "tilt" of a video display of a video monitor.
It is another object of the invention to provide a video preamplifier of the type described that utilizes the benefits of MOS transistors achievable in a LinBiCMOS process to reduce or eliminate current leakages that may otherwise result in picture tilt on a video display. Since there is essentially no leakage in MOS transistors, LinBiCMOS integrated circuit processes are ideally well suited to solve the problem addressed by this invention.
These and other objects, features and advantages of the invention will be apparent to those skilled in the art from the following detailed description of the invention, when read in conjunction with the accompanying drawings and appended claims.
In accordance with a broad aspect of the invention, a circuit is presented for reducing a tilt of a video picture on a color monitor of the type in which vertical displacement of a scanning beam is controlled by a magnitude of a scan control signal. The circuit includes a circuit for providing an output signal for controlling the vertical position of the scanning beam that includes an MOS transistor having substantially zero current flow in a gate element, and connected to control the magnitude of the output signal. In a preferred embodiment, a LinBiCMOS semiconductor manufacturing process is employed to fabricate a plurality of bipolar transistors connected to provide a control voltage on the gate of the MOS transistor, which may conveniently be an NMOS device.
The bipolar transistors may be connected to form a translinear cell connected to receive a signal related to a horizontal synchronizing signal and to provide a voltage output to the gate of the MOS transistor in response thereto.
According to another broad aspect of the invention, a circuit is presented for reducing a tilt of a video picture on a color monitor of the type in which vertical displacement of a scanning beam is controlled by a magnitude of a scan control signal. The circuit includes a circuit for providing the scan control signal with substantially constant magnitude. A circuit is also provided for enabling and disabling the circuit for providing the scan control signal. The circuit for providing the scan control signal with substantially constant magnitude preferably comprises a MOS transistor, for example, an NMOS transistor.
The circuit is preferably made by a LinBiCMOS semiconductor manufacturing process, wherein the circuit for enabling and disabling the circuit for providing the scan control signal includes bipolar transistors.
According to yet another broad aspect of the invention, a circuit is provided for reducing a tilt of a video picture on a color monitor of the type in which vertical displacement of a scanning beam is controlled by a magnitude of a scan control signal, the circuit being formed by a particular process. The process includes the steps of forming a circuit for providing a scan control signal having substantially constant magnitude and forming a circuit for enabling and disabling the circuit for providing the scan control signal. The step of forming a circuit for providing a scan control signal having substantially constant magnitude preferably includes forming an MOS transistor in a semiconductor substrate, and the step of forming a circuit for enabling and disabling the circuit for providing the scan control signal preferably includes forming a bipolar circuit in the semiconductor substrate. Preferably, the steps of forming a circuit for providing a scan control signal having substantially constant magnitude comprises forming an MOS transistor in a semiconductor substrate and forming a circuit for enabling and disabling the circuit for providing the scan control signal comprises forming a bipolar circuit in the semiconductor substrate are performed as a part of a LinBiCMOS process.
According to still another broad aspect of the invention, a method is presented for reducing a tilt of a video picture on a color monitor of the type in which vertical displacement of a scanning beam is controlled by a magnitude of a scan control signal. The method includes the steps of providing the scan control signal with substantially constant magnitude and enabling and disabling the circuit for providing the scan control signal. The step of providing the scan control signal with substantially constant magnitude preferably includes constructing a circuit to provide the scan control signal using a MOS transistor, and in a preferred embodiment, an NMOS transistor, that has substantially no gate leakage current. Also, preferably, the step of enabling and disabling the circuit for providing the scan control signal includes operating bipolar transistors connected as a translinear cell to enable and disable the circuit for providing the scan control signal.
BRIEF DESCRIPTION OF THE DRAWING
The invention is illustrated in the accompanying drawing, in which:
FIG. 1 is an electrical schematic diagram of a circuit for controlling a video drive signal to reduce or eliminate "tilt" of a displayed video picture on a color monitor, in accordance with a preferred embodiment the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An electrical schematic diagram of a "black level hold" circuit 10 for maintaining a video picture without "tilt", in accordance with a preferred embodiment of the invention, is shown in FIG. 1. The circuit 10 comprises a translinear, or differential current mirror, cell 11, an associated active input current source 12, and output current mirrors 13, 14, and 15.
The differential current mirror cell 11 is turned on or off, or enabled and disabled, in response to a sync timing related bias voltage applied to an input line 17. The bias voltage applied to line 17 is sometimes referred to herein as a signal related to a horizontal synchronizing signal, since the bias voltage on line 17 is derived from an associated circuit in another part of the preamplifier (not shown) that indicates the period of a single horizontal sweep. Such video circuits and horizontal sweep signals are well known in the art. The bias voltage on line 17 is applied to the base of a NPN transistor 19. The NPN transistor 19, together with a resistor 20 from its collector to a ground or reference potential rail 22, form a current source that is turned on and off by the bias voltage. Thus, during the retrace period of the horizontal sweep, the output of the OSD controller or equivalent circuitry is high. This enables the black level hold circuitry 10. On the other hand, during the video period of the horizontal sweep, the voltage on line 17 is low, and the black level hold circuitry 10 is disabled.
The translinear circuit 11 has two NPN transistors 24 and 25, each controlling a respective current flow path, in response to the input DC voltage levels on the CLAMP+ line 27 and the DCOUT level on line 28. The CLAMP+ voltage is applied to the base of a PNP transistor 29 and the output DC level from the video preamplifier 30 is fed back on line 28 to the base of a corresponding PNP transistor 32 by a resistor 33. The value of the CLAMP+ voltage is normally established by the maker of the monitor (not shown) in conjunction with which the circuit 10 is to be used. The CLAMP+ level establishes the output DC level from the video preamplifier 30 to a value, generally between about 1.5 V and 2.0 V. The differential current mirror circuit 11 compares the CLAMP+ voltage with the level of the DC output, and depending upon whether the CLAMP+ voltage is larger or smaller, turns on transistor 24 or 25 to control the output current mirrors 13 or 14.
The active input current source 12 has two PNP transistors 35 and 36 to provide an input reference current through the resistor 37 and PNP transistor 29. Balancing the translinear cell 11 is a PNP transistor 39 in series with a resistor 40, matching the electrical characteristics of the PNP transistor 36 and resistor 37. Finally, two PNP transistors 42 and 43 are connected between the respective bases of NPN transistors 24 and 25 and the reference potential rail 22, with their bases connected respectively to the collectors of PNP transistors 29 and 32. The PNP transistors 42 and 43 serve to connect the bases of the NPN transistors 24 and 25 to the reference potential rail 22 when the PNP transistors 29 or 32 are conducting. A resistor 38 is connected between the emitters of the PNP transistors 29 and 32 across which the differential input voltage appears. The value of the resistance 20 used determines the gain of the translinear cell 11.
First and second output mirror circuits 13 and 14 are connected in the respective current flow paths of the NPN transistors 24 and 25 of the translinear cell 11. The mirror circuits 13 and 14 are of the so-called Wilson mirror type, the mirror circuit 13 having three PNP transistors 45, 46, and 47, and the mirror circuit 14 having three PNP transistors 48, 49, and 50. The first PNP transistor 45 of the current mirror 13 is connected directly between the V cc rail 16 and the current flow path of the NPN transistor 25. The second PNP transistor 46 is connected in series with the third PNP transistor 47, which has its base connected to the collector of the NPN transistor 25 of the translinear circuit 11. Thus, the current that flows in the PNP transistor 47 mirrors the current that flows through the PNP transistor 45 and the NPN transistor 25 when the circuit 10 is selected in dependence upon the state of the bias voltage appearing on line 17.
In similar fashion, the first PNP transistor 48 of the mirror circuit 14 is connected between the V cc rail and the current flow path of the NPN transistor 24 of the translinear circuit 11. Additionally, the second PNP transistor 49 is connected in series with the third PNP transistor 50, which has its base connected to the collector of the NPN transistor 24 of the translinear circuit 11. Thus, the current that flows in the PNP transistor 50 mirrors the current that flows through the PNP transistor 48 and the NPN transistor 24 when the circuit 10 is selected in dependence upon the state of the bias voltage appearing on line 17.
The third output mirror circuit 15 is a cross coupled collector current source type, with the current supplied to each leg via the PNP transistors 47 and 50 of the current mirrors 13 and 14. The current mirror 15 includes three NPN transistors 52, 53, and 54. The NPN transistors 52 and 53 are connected from the collectors of the PNP transistors 47 and 50, respectively, to the reference potential rail 22.
An N-channel MOS transistor 60, which may be a linear MOS device, is connected between the input stage 61 of the video preamplifier and the reference potential rail 22, with its gate connected to the collector of the mirror transistor 52. One of the advantages derived from the use of a MOS device of the type described is that such MOS device has essentially zero current leakage from its base, therefore, the charge on the capacitor 64 used to establish the control voltage on the NMOS device 60 is not discharged through undesired leakage by the video level adjust transistor. Thus, the bias on the video preamplifier circuit 30 is maintained at a constant desired level. Since the circuit includes both linear MOS devices and bipolar transistors, preferably, the circuit can be integrated onto a single semiconductor substrate, denoted by the dotted line 63, by a suitable LinBiCMOS semiconductor manufacturing process. Such LinBiCMOS processes are known in the art, and therefore are not described in detail herein.
Finally, the capacitor 64, which establishes the control voltage on the gate of the NMOS device 60, is connected between the gate of the NMOS transistor 60 and the reference potential rail 22. The capacitor 64 may be externally connected if desired, and may have a typical value, for example, of 0.1 μF. Thus, the state of conduction of the NPN transistor 52 determines whether the capacitor 64 is charged by the current through the PNP transistor 47, or is discharged through the NPN transistor 52.
Since the transistor pairs 45 and 46, and pairs 48 and 49 function as current mirror circuits, the current that flows through the current mirror circuits provided by transistors 52 and 53 mirror the currents flowing respectively through the NPN transistors 24 and 25.
When the transistor 52 conducts, the voltage on its collector drops towards the reference potential, to discharge the charge on the capacitor 64, and turn the NMOS transistor 60 off. As a result, the capacitor 64 is either charged through the PNP transistors 46 and 47, or discharged through the NPN transistor 52. Thus, the node voltage at the gate of the NMOS transistor 60 is set to determine how hard the NMOS transistor 60 should pull from the bias level at the input stage 61 to the video preamplifier 30.
It should be appreciated that since the transistor 60 is implemented by an NMOS device, instead of by a traditional bipolar device, the thermal effects that result in the "tilt" of the video picture are reduced or eliminated entirely.
Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example, and that numerous changes in the combination and arrangement of parts can be resorted to by those skilled in the art without departing from the spirit and scope of the invention, as hereinafter claimed. | A circuit (10) and method for reducing a tilt of a video picture on a color monitor includes a circuit (30) for providing an output signal for controlling the vertical position of the scanning beam that includes an MOS transistor (60) having substantially zero current flow in its gate element, and connected to control the magnitude of the output drive signal. In a preferred embodiment, a LinBiCMOS semiconductor manufacturing process is employed to fabricate a plurality of bipolar transistors connected to provide a control voltage on the gate of the MOS transistor (60), which may conveniently be an NMOS device. The bipolar transistors may be connected to form a translinear cell (11) connected to receive a signal (17) related to a horizontal synchronizing signal and to provide a voltage output to the gate of the MOS transistor (60) in response thereto. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to the field of imaging. More particularly, the present invention relates to a method of automatic detection and correction of halo artifacts in images.
BACKGROUND OF THE INVENTION
[0002] Halo artifacts are a type of image artifacts that appear visible across edges of an image that has generally been processed by an image processing algorithm. These artifacts are characterized by overestimation (“overshoot”) on one side of the edge and underestimation (“undershoot”) on the other side of the edge. Halo artifacts typically appear as visible, unwanted shadows across the edges in the processed image. FIG. 1A illustrates an original, unprocessed image, while FIG. 1B illustrates a halo artifact in the processed image. The halo artifact is most prevalent across the edge between the light area on the left and the darker area on the right. Common image processing methods that generate halo artifacts are high dynamic range compression methods, which rely on Gaussian style blurring (such as Land and McCann's Retinex method). Other common methods that may generate halo artifacts are edge enhancement methods, which include unsharp masking and Wallis Filter [statistical differencing], and other filtering methods.
[0003] In the paper, “Gradient domain high dynamic range compression” by Fattal et al., the idea of performing high dynamic range compression by modifying only the magnitudes of the two-dimensional gradient field is proposed. The gradient field is computed as the finite difference in adjacent pixel intensities across a luminance (grayscale) image, on both the horizontal and vertical directions of the image. For each pixel location, the set of horizontal and vertical gradient form a two-dimensional gradient vector. This two-dimensional gradient vector can be characterized by direction and magnitude. The gradient field associated with a specific image includes a plurality of gradient vectors. Fattal et al. propose a method for dynamic range compression that is free from halo artifacts by computing the two-dimensional gradient field in the original image and attenuating only the magnitude of the gradient vectors, preserving the direction of the gradient vectors.
SUMMARY OF THE INVENTION
[0004] A method of automatic detection and correction of halo artifacts within a processed image is described. Halo artifacts are typically manifested as bands or shadows along edges within an image that has been processed using one or more processing algorithms. The detection and the correction methods rely on computing a two-dimensional gradient field of the original image and a two-dimensional gradient field of the processed image. Each gradient field includes a gradient vector corresponding to each pixel. To detect halo artifacts, the gradient vector at each pixel of the original image is compared to the gradient vector at the corresponding pixel of the processed image. A halo artifact is determined to exist at a given pixel if the direction of the two corresponding gradient vectors differs by at least a specified threshold amount.
[0005] To correct the halo artifacts, a composite gradient field is generated. In a first correction method, a composite gradient vector is generated for each pixel. If a halo artifact is deemed to exist at a given pixel, then the composite gradient vector includes the direction from the corresponding gradient vector in the original image and the magnitude from the corresponding gradient vector in the processed image. If a halo artifact is not deemed to exist at a given pixel, then the composite gradient vector includes the direction and magnitude from the corresponding gradient vector in the processed image. In a second correction method, the composite gradient vector for each pixel includes the direction from the corresponding gradient vector in the original image and the magnitude from the corresponding gradient vector in the processed image. In a third correction method, if a halo artifact is deemed to exist at a given pixel, then the composite gradient vector includes the direction and magnitude from the corresponding gradient vector in the original image. If a halo artifact is not deemed to exist at a given pixel, then the composite gradient vector includes the direction from the corresponding gradient vector in the original image and the magnitude from the corresponding gradient vector in the processed image. A final image is generated by integrating the newly generated composite gradient field using known two-dimensional integration methods such as ones based on the Fast Fourier Transform.
[0006] In one aspect, a method of detecting halo artifacts in an image is disclosed. The method comprises determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, one first gradient vector associated with each pixel in the image, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, one second gradient vector associated with each pixel in the processed image, wherein a first pixel in the image corresponds to a first pixel in the processed image, calculating a gradient angle for each pixel, wherein a first gradient angle is an angle between a first gradient vector and a second gradient vector associated with the first pixel, and calculating a relative angle for each pixel, wherein a first relative angle for the first pixel is the minimum between the first gradient angle and 360 degrees minus the first gradient angle. In some embodiments, a halo artifact value at each pixel is defined as the relative angle at the pixel. In other embodiments, a halo artifact value at each pixel is defined as a magnitude of the second gradient vector at the pixel. In some embodiments, the first gradient angle between the first gradient vector and the second gradient vector is the absolute value. In some embodiments, the first gradient field is determined according to a scale that identifies a pixel separation distance used in the determination of each first gradient vector. In some embodiments, the second gradient field is determined according to the scale. As a general rule, the scale increases as noise in the image increases. In some embodiments, the image is a grayscale image. If the image is a color image, the method further comprises converting the image to a grayscale image before determining the first two-dimensional gradient field.
[0007] In another aspect, a method of correcting halo artifacts in an image is disclosed. The method comprises determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, further wherein each second gradient vector corresponds to a specific first gradient vector, thereby forming a first gradient vector and second gradient vector pair, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector corresponds to a specific first gradient vector and second gradient vector pair, and each third gradient vector includes a third magnitude equal to the second magnitude of the corresponding second gradient vector and a third direction equal to the first direction of the corresponding first gradient vector, and integrating the third gradient field thereby generating a corrected image. In some embodiments, integrating the third gradient field comprises integrating the third gradient field according to known integrating methods from a two-dimensional gradient field based on a Fast Fourier Transform. In some embodiments, the plurality of first gradient vectors includes one first gradient vector for each pixel in the image. In some embodiments, the plurality of second gradient vectors includes one second gradient vector for each pixel in the processed image, wherein a first pixel in the image corresponds to a first pixel in the processed image. In some embodiments, one first gradient vector and second gradient vector pair corresponds to each pixel. In some embodiments, the first gradient field is determined according to a scale that identifies a pixel separation distance used in the determination of each first gradient vector. In some embodiments, the second gradient field is determined according to the scale. In some embodiments, the image is a grayscale image. If the image is a color image, the method further comprises converting the image to a grayscale image before determining a first two-dimensional gradient field.
[0008] In yet another aspect, a method of detecting and correcting halo artifacts in an image is disclosed. The method comprises determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, quantifying a halo artifact value at each pixel, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector includes a third magnitude and a third direction, further wherein if the halo artifact value at a given pixel is less than a predetermined value, then the third magnitude equals the second magnitude and the third direction equals the second direction at the given pixel, and if the halo artifact value at the given pixel is greater than or equal to the predetermined value, then the third magnitude equals the second magnitude and the third direction equals the first direction at the given pixel, and integrating the third gradient field thereby generating a corrected image. In some embodiments, quantifying a halo artifact value at each pixel comprises calculating a gradient angle for each pixel, wherein the gradient angle defines a difference in the direction between the first gradient vector and the second gradient vector at the given pixel, and calculating a relative angle for each pixel, wherein the relative angle for the given pixel is the minimum between the gradient angle at the given pixel and 360 degrees minus the gradient angle at the given pixel, further wherein the relative angle equals the halo artifact value at each pixel. In some embodiments, each second gradient vector corresponds to a specific first gradient vector, thereby forming a first gradient vector and second gradient vector pair, and each third gradient vector corresponds to a specific first gradient vector and second gradient vector pair. In some embodiments, one first gradient vector associated with each pixel in the image and one second gradient vector associated with each pixel in the processed image, further wherein a first pixel in the image corresponds to a first pixel in the processed image. In some embodiments, a first gradient angle is an angle between a first gradient vector and a second gradient vector associated with the first pixel. In some embodiments, integrating the third gradient field comprises integrating the third gradient field according to known integration methods from a two-dimensional gradient field based on a Fast Fourier Transform. In some embodiments, the first gradient field is determined according to a scale that identifies a pixel separation distance used in the determination of each first gradient vector. In some embodiments, the second gradient field is determined according to the scale. In some embodiments, the image is a grayscale image. If the image is a color image, the method further comprises converting the image to a grayscale image before determining a first two-dimensional gradient field.
[0009] In another aspect, a method of detecting and correcting halo artifacts in an image is disclosed. The method includes determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, quantifying a halo artifact value at each pixel, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector includes a third magnitude and a third direction, further wherein if the halo artifact value at a given pixel is less than a predetermined value, then the third magnitude equals the second magnitude and the third direction equals the first direction at the given pixel, and if the halo artifact value at the given pixel is greater than or equal to the predetermined value, then the third magnitude equals the first magnitude and the third direction equals the first direction at the given pixel, and integrating the third gradient field thereby generating a corrected image. In some embodiments, quantifying the halo artifact value at each pixel includes calculating a gradient angle for each pixel, wherein the gradient angle defines a difference in the direction between the first gradient vector and the second gradient vector at the given pixel, and calculating a relative angle for each pixel, wherein the relative angle for the given pixel is the minimum between the gradient angle at the given pixel and 360 degrees minus the gradient angle at the given pixel, further wherein the relative angle equals the halo artifact value at each pixel. In some embodiments, the predetermined value is 90 degrees. In some embodiments, each second gradient vector corresponds to a specific first gradient vector, thereby forming a first gradient vector and second gradient vector pair, and each third gradient vector corresponds to a specific first gradient vector and second gradient vector pair. In some embodiments, one first gradient vector is associated with each pixel in the image and one second gradient vector is associated with each pixel in the processed image, further wherein a first pixel in the image corresponds to a first pixel in the processed image. In this case, a first gradient angle is an angle between a first gradient vector and a second gradient vector associated with the first pixel. In some embodiments, integrating the third gradient field comprises integrating the third gradient field according to known integration methods from a two-dimensional gradient field based on a Fast Fourier Transform. In some embodiments, the first gradient field is determined according to a scale that identifies a pixel separation distance used in the determination of each first gradient vector. In this case, the second gradient field is also determined according to the scale. In some embodiments, the image is a grayscale image. If the image is a color image, the method further comprises converting the image to a grayscale image before determining a first two-dimensional gradient field.
[0010] In still yet another aspect, an apparatus for detecting halo artifacts in an image is disclosed. The apparatus includes an application, a processor configured for executing the application, and a memory coupled to the processor, the memory configured for temporarily storing data for execution by the processor. The application is configured for determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, quantifying a halo artifact value at each pixel, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector includes a third magnitude and a third direction, further wherein if the halo artifact value at a given pixel is less than a predetermined value, then the third magnitude equals the second magnitude and the third direction equals the second direction at the given pixel, and if the halo artifact value at the given pixel is greater than or equal to the predetermined value, then the third magnitude equals the second magnitude and the third direction equals the first direction at the given pixel, and integrating the third gradient field thereby generating a corrected image.
[0011] In another aspect, an apparatus for correcting halo artifacts in an image is disclosed. The apparatus includes an application, a processor configured for executing the application, and a memory coupled to the processor, the memory configured for temporarily storing data for execution by the processor. The application is configured for determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, further wherein each second gradient vector corresponds to a specific first gradient vector, thereby forming a first gradient vector and second gradient vector pair, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector corresponds to a specific first gradient vector and second gradient vector pair, and each third gradient vector includes a third magnitude equal to the second magnitude of the corresponding second gradient vector and a third direction equal to the first direction of the corresponding first gradient vector, and integrating the third gradient field thereby generating a corrected image.
[0012] In yet another aspect, an apparatus for detecting halo artifacts in an image is disclosed. The apparatus includes an application, a processor configured for executing the application, and a memory coupled to the processor, the memory configured for temporarily storing data for execution by the processor. The application is configured for determining a first two-dimensional gradient field for an image, wherein the first gradient field includes a plurality of first gradient vectors, each first gradient vector includes a first magnitude and a first direction, determining a second two-dimensional gradient field for the processed image, wherein the second gradient field includes a plurality of second gradient vectors, each second gradient vector includes a second magnitude and a second direction, quantifying a halo artifact value at each pixel, generating a third two-dimensional gradient field, wherein the third gradient field includes a plurality of third gradient vectors, each third gradient vector includes a third magnitude and a third direction, further wherein if the halo artifact value at a given pixel is less than a predetermined value, then the third magnitude equals the second magnitude and the third direction equals the first direction at the given pixel, and if the halo artifact value at the given pixel is greater than or equal to the predetermined value, then the third magnitude equals the first magnitude and the third direction equals the first direction at the given pixel, and integrating the third gradient field thereby generating a corrected image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1A illustrates an unprocessed image.
[0014] FIG. 1B illustrates a corresponding processed image including a halo artifact.
[0015] FIG. 2 illustrates a method of detecting halo artifacts.
[0016] FIG. 3 illustrates an exemplary gradient angle.
[0017] FIG. 4 illustrates a first correction method.
[0018] FIG. 5 illustrates a second correction method.
[0019] FIG. 6 illustrates a third correction method.
[0020] FIG. 7 illustrates a graphical representation of an exemplary computing device configured to implement the detection and correction method of the present invention.
[0021] Embodiments of the detection and correction method are described relative to the several views of the drawings. Where appropriate and only where identical elements are disclosed and shown in more than one drawing, the same reference numeral will be used to represent such identical elements.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0022] The detection and correction methods address the problem of unsupervised detection and correction of halo artifacts in a processed image. Embodiments of the detection and correction methods are based on the observation that in processed images that contain halo artifacts, the halo artifacts appear as reversed gradients across edges within the two images. The detection method detects halo artifacts and points to the image regions where they occur. In particular, the detection method describes a manner of quantifying the halo artifacts by measuring the gradient angle between the two-dimensional gradient fields in the original image and the processed image.
[0023] The detection and correction methods are completely automatic and do not rely on a specific target. Instead, the detection and correction methods are based on comparing the two-dimensional (2D) gradient field in the original, unprocessed image and the 2D gradient field in the processed image containing halo artifacts. Halo artifacts are present in those regions of the processed image where the direction of the gradient field is reversed, or is significantly different, as compared to the same region in the original image.
[0024] FIG. 2 illustrates a method of detecting halo artifacts. At the step 10 , an original image is processed according to one or more processing algorithms, including but not limited to, a high dynamic range compression algorithm. As a result of processing the original image using one of these processing algorithms, halo artifacts may be generated. To detect such halo artifacts, at the step 20 , a two-dimensional gradient field is calculated for the original image. In some embodiments, the 2D gradient field for the original image includes one gradient vector for every n th pixel within the original image. At the step 30 , a two-dimensional gradient field is computed for the processed image generated in the step 10 . In some embodiments, the 2D gradient field for the processed image includes one gradient vector for every n th pixel within the processed image. Each pixel within the original image corresponds to a specific pixel in the processed image. Both the 2D gradient field for the original image and the 2D gradient field for the processed image are computed according to a specific scale. The scale identifies the number of pixels used in the computation of each gradient vector. For example, if the scale is 1, to compute the gradient vector for pixel A, the pixels adjacent to pixel A are used. For a scale of 10, the gradient vector for pixel A is computed using pixels ten (10) pixels apart from pixel A. The gradient field is computed in both the x-direction and the y-direction. Both the magnitude and the direction of the gradient field, as defined by the gradient vector, is determined for each pixel. The magnitude of the gradient vector quantifies the difference between the pixel associated with the gradient vector and the surrounding pixels separated by the scale.
[0025] At the step 40 , a gradient angle for each pixel is calculated. For each pixel, there is a corresponding gradient vector of the original image and a gradient vector of the processed image. The gradient angle is calculated as the difference in direction between the two gradient vectors. FIG. 3 illustrates an exemplary gradient angle θ. A gradient vector 6 is associated with pixel A within an original image 2 . A gradient vector 8 is associated with pixel A within a corresponding processed image 4 . The directional difference between the gradient vector 4 and the gradient vector 8 is the gradient angle θ. In some embodiments, the gradient angle is measured according to standard polar coordinates. For example, if the gradient vector points horizontally from left to right, the angle is zero. If the gradient vector points horizontally from right to left, the angle is 180 degrees.
[0026] At the step 50 ( FIG. 2 ), the absolute value is calculated for each gradient angle calculated in the step 40 . The result is referred to as the absolute gradient angle, which is measured in degrees. At the step 60 , a relative gradient angle is calculated for each absolute gradient angle calculated in the step 50 . The relative gradient angle is calculated as the minimum between the absolute gradient angle and 360 minus the absolute gradient angle. In this manner, the relative gradient angle has a value less than or equal to 180 degrees. At pixel A, if the gradient vectors from the original image and the processed image are in complete opposite direction, the relative gradient angle at pixel A has a maximum value. If the gradient vectors are in the same direction, the relative gradient angle is zero.
[0027] At the step 70 , it is determined if the relative gradient angle calculated at the step 60 is greater than or equal to a specific threshold value. At the step 80 , a halo artifact value is defined for each pixel that has a relative gradient angle greater than or equal to the threshold value. In a first method of detection, the halo artifact value for each such pixel is defined as the value of the relative gradient angle. In a second method of detection, the specified threshold value is defined as 90 degrees, and for each pixel that has a relative gradient angle greater than or equal to 90 degrees, the halo artifact value is defined by the magnitude of the gradient vector in the processed image. The detection method automatically quantifies and identifies areas in the original image that give rise to halo artifacts due to a variety of spatial processing techniques.
[0028] The gradient field is susceptible to noise. The scale at which the gradient vectors are computed can be adjusted to affect the robustness of the method. For example, if the image is noisy, the gradient field is calculated using a larger scale. For images that are expected to be noise-free, a scale of 1 may be appropriate. A scale of 1 simply means that gradients are computed by discrete differences between adjacent pixels in the image. For noisier images, a scale of 3 or 5 may provide more robust results. For additional robustness, a threshold for low values of the relative gradient angle can be used such that values very close to zero are identified as “no halo artifacts” instead of “low halo artifacts.” In other words, for small relative gradient angles, the relative gradient angle is treated as zero degrees in some applications, which corresponds to no halo artifact.
[0029] The detection method described above works for grayscale images. For typical color images, the method is applied by first converting the image to grayscale.
[0030] The correction methods provide automated correction of halo artifacts. The correction methods include computing and comparing the 2D gradient field of the original and processed images. Correction for the halo artifacts is accomplished using one of three methods. In a first correction method, the correction method is applied only to those pixels where the calculated relative gradient angle is greater than or equal to the specific threshold. In this case, a new 2D gradient field is determined where the magnitude and direction of the gradient vector for those pixels where the relative gradient angle is less than the specific threshold is determined according to the magnitude and direction of the gradient vector of the processed image. For those pixels where the relative gradient angle is greater than or equal to the specific threshold, the direction of the new 2D gradient vector is determined according to the direction of the gradient vector in the original image and the magnitude of the new 2D gradient vector is determined according to the magnitude of the gradient vector in the processed image. In a second correction method, the new 2D gradient field is determined by taking the direction from the original image and the magnitude from the processed image at every pixel, regardless of the value of the relative gradient angle at a given pixel. In a third correction method, the new 2D gradient filed is determined where the magnitude and direction of the gradient vector for those pixels where the relative gradient angle is greater than or equal to 90 degrees is determined according to the magnitude and direction of the gradient vector of the original image. For those pixels where the relative gradient angel is less than 90 degrees, the direction of the new 2D gradient vector is determined according to the direction of the gradient vector in the original image and the magnitude of the new 2D gradient vector is determined according to the magnitude of the gradient vector in the processed image.
[0031] FIG. 4 illustrates the first correction method. At the step 100 , a first new 2D gradient field is generated. When the gradient field of the original image and the gradient field of the processed image each include one gradient vector for each pixel, the new gradient field also includes one gradient vector for each pixel. For a given pixel, the relative gradient angle is compared to a specific threshold value. If it is determined that the relative gradient angle meets or exceeds the specified threshold, for example as determined at the step 70 in FIG. 2 , then for the given pixel, the direction of the gradient vector for the first new gradient field is equal to the direction of the corresponding gradient vector for the gradient field of the original image. If instead it is determined that the relative gradient angle is less than the specified threshold, then the direction of the gradient vector for the first new gradient field is equal to the direction of the corresponding gradient vector for the gradient field of the processed image. The magnitude of the gradient vector for the first new gradient field is equal to the magnitude of the corresponding gradient vector for the gradient field of the processed image, regardless of the value of the relative gradient angle. In this manner, the first correction method is applied to select regions to eliminate or reduce the halo artifacts. At the step 110 , the new gradient field is integrated to generate a corrected image. In some embodiments, the integration is performed according to a Fast Fourier Transform.
[0032] In the second correction method, correcting the halo artifacts does not require quantifying the halo artifacts. Instead, each gradient vector for a second new gradient field is generated by using the magnitude from the gradient vector of the processed image and the direction from the gradient vector of the original image. As described above, the original image is processed according to one or more processing algorithms that generate halo artifacts, thereby generating the processed image that includes halo artifacts. The 2D gradient field is then calculated for the original image and the 2D gradient field is computed for the processed image. Both the 2D gradient field for the original image and the 2D gradient field for the processed image are computed according to a specific scale, as previously described. Both the magnitude and the direction of the gradient field, as defined by the gradient vector, is determined for each pixel.
[0033] FIG. 5 illustrates the second correction method. At the step 120 , a second new 2D gradient field is generated. Each gradient vector within the second new 2D gradient field is determined by taking the direction from the gradient vector of the original image and the magnitude from the gradient vector of the processed image at every pixel, regardless of whether or not a halo artifact exists at a given pixel. In this manner, the magnitude of the gradient vector for the second new gradient field is equal to the magnitude of the corresponding gradient vector for the gradient field of the processed image, and the direction of the gradient vector for the second new gradient field is equal to the direction of the corresponding gradient vector for the gradient field of the original image. At the step 130 , the second new gradient field is integrated to generate a corrected image. In some embodiments, the integration is performed according to a Fast Fourier Transform.
[0034] FIG. 6 illustrates the third correction method. The third correction method defines the specific threshold value as 90 degrees. At the step 140 , a third new 2D gradient field is generated. For a given pixel, the relative gradient angle is compared to the specific threshold value, which in this case is 90 degrees. If it is determined that the relative gradient angle is greater than or equal to 90 degrees, then for the given pixel, the direction and magnitude of the gradient vector for the third new gradient field is equal to the direction and magnitude of the corresponding gradient vector for the gradient field of the original image. If instead it is determined that the relative gradient angle is less than 90 degrees, then the direction of the gradient vector for the third new gradient field is equal to the direction of the corresponding gradient vector for the gradient field of the original image, and the magnitude of the gradient vector for the third new gradient field is equal to the magnitude of the corresponding gradient vector for the gradient field of the processed image. At the step 150 , the third new gradient field is integrated to generate a corrected image. In some embodiments, the integration is performed according to a Fast Fourier Transform.
[0035] The correction methods described above work for grayscale images. For typical color images, the correction methods are applied either by first converting the image to grayscale and then converting back to color images, or by applying the correction methods on each of the color channels individually.
[0036] FIG. 7 illustrates a graphical representation of an exemplary computing device configured to implement the detection and correction methods of the present invention. A computing device 200 includes a display 202 , a memory 204 , a processor 206 , a storage 208 , an acquisition unit 210 , and a bus 212 to couple the elements together. The acquisition unit 210 acquires image data, which is then processed by the processor 206 and temporarily stored in the memory 204 and more permanently stored on the storage 208 . The display 202 displays the image data acquired either during acquisition or when utilizing a display feature. When the detection and correction methods described herein are implemented in software, an application 214 resides on the storage 208 , and the processor 206 processes the necessary data while the amount of the memory 204 used is minimized. When implemented in hardware, additional components are utilized to process the data, as described above. The computing device 200 is able to be, but is not limited to, a digital camcorder, a digital camera, a cellular phone, PDA, or computer.
[0037] In some embodiments, the detection and correction methods are automated. Automatic detection and correction of halo artifacts significantly increases the usability of spatial processing algorithms that would otherwise be considered unsuitable due to their undesirable artifacts. The detection and correction methods are used as a post-processing step after an image has been processed with a spatial processing algorithm, such as a high dynamic range compression algorithm, that generates halo artifacts. The detection and correction methods are used to remove these unwanted halo artifacts. Other types of image processing algorithms that produce halo artifacts may also benefit from this method.
[0038] The present invention has been described in terms of specific embodiments incorporating details to facilitate the understanding of the principles of construction and operation of the invention. Such references, herein, to specific embodiments and details thereof are not intended to limit the scope of the claims appended hereto. It will be apparent to those skilled in the art that modifications can be made in the embodiments chosen for illustration without departing from the spirit and scope of the invention. | A method of automatically detecting and correcting halo artifacts within a processed image is described. The method computes a two-dimensional (2D) gradient field of the original image and a 2D gradient field of the processed image. Each gradient field includes a gradient vector corresponding to each pixel. To detect halo artifacts, the gradient vector at each pixel of the original image is compared to the gradient vector at the corresponding pixel of the processed image. A halo artifact is determined to exist at a given pixel if a direction of the two corresponding gradient vectors differs by at least a specified threshold. To correct the halo artifacts, a composite gradient field is generated using one of three correction methods. A final image is generated by integrating the newly generated composite gradient field using known integration methods from a 2D gradient field such as ones based on the Fast Fourier Transform. | 6 |
BACKGROUND OF THE INVENTION
[0001] The invention concerns a folded box, in particular of carton, comprising two principal wall sections which are connected to each other on one side, in particular through a principal folding line, and can be connected to each other on the opposite side e.g. by a flap, to form a substantially tubular body whose ends can be closed. The invention also concerns a folded box of a one-piece blank.
[0002] Conventional cushioned packages have closing sections which can be folded on top of each other to close the cushioned package. The closing sections of cushioned packages simultaneously serve to shape and keep the shape of the substantially tubular body. The closing sections of cushioned packages are e.g. elliptical. The non-rectangular contour of the closing sections prevents use of a rectangular blank for cushioned packages. For production, an intermediate section is therefore required between two blanks. The non-rectangular contour of the closing sections of cushioned packages increases the material consumption since the material between the closing sections of two different blanks must be removed. Moreover, closing of the cushioned packages by hand is relatively demanding since the closing sections must be folded successively against each other. Moreover, cushioned packages cannot be closed in a fluid-tight fashion through welding or sealing.
[0003] It is therefore the underlying purpose of the invention to provide a blank, which can be produced in an easy and inexpensive fashion, for a folded box which can be closed by hand. A further object of the invention consists in providing a folded box of a one-piece blank of simple construction which can be produced in an inexpensive fashion. The inventive folded box shall be easy to close manually and also by a machine.
SUMMARY OF THE INVENTION
[0004] This object is achieved in a one-piece, in particular, rectangular blank for a folded box, in particular of carton, comprising two main wall sections which are connected to each other on one side, in particular by a principal folding line and can be connected to each other on the opposite side e.g. by a flap to form a substantially tubular body, whose ends can be closed, in that in at least one of the two principal wail sections, a side wall section with tapering ends is formed. The side wall section gives the tubular body a stable spatial shape.
[0005] A preferred embodiment of the blank is characterized in that the side wall section is formed by two folding lines which are separated from each other in the center and merge into each other at the ends. The folding lines provide the tubular body with a polygonal cross-section. Usually, two side wall sections are disposed opposite to each other to provide the tubular body with a rectangular cross-section in the center.
[0006] A further preferred embodiment of the blank is characterized in that the two folding lines forming the side wall section are disposed parallel to each other in the central region, which gives the tubular body a the shape of a right parallelepiped in the central region.
[0007] A further preferred embodiment of the blank is characterized in that the side wall section has triangular ends providing the cross-section of the tubular body with particular stability.
[0008] A further preferred embodiment of the blank is characterized in that the side wall section has the shape of an ellipse which provides the folded box produced from the blank with an optically pleasant shape. The cross-section of the tubular body decreases from the center to the outside.
[0009] A further preferred embodiment of the blank is characterized in that the principal wall sections on the tapering ends of the side wall section merge into closing sections. The closing sections abut each other when the folded box is assembled. This greatly facilitates closing of the folded box by hand and by machine.
[0010] A further preferred embodiment of the blank is characterized in that closure folding lines are formed between the principal sections and the closing sections. The closure folding lines permit surface abutment of the closing sections providing fluid-tight closure of the folded box.
[0011] A further preferred embodiment of the blank is characterized in that the closure folding lines are disposed substantially transversely to the at least one side wall section and the distance between the closure folding lines and the associated edge of the respective closing section is not constant but varies. This ensures safe closure of a package produced from the blank.
[0012] A further preferred embodiment of the blank is characterized in that a side wall section with tapering ends is formed in both principal wall sections and that a continuous folding line is disposed between and substantially parallel to the side wall sections. The continuous folding line ensures folding of the tubular body for storage or transport. The continuous folding line also facilitates machine production on conventional gluing machines and facilitates insertion of products.
[0013] A further preferred embodiment of the blank is characterized in that the distance between the closure folding lines and the associated edge of the respective closing section increases starting from the side wall sections to the inside and to the outside. Abutting closing sections are thereby held together in the erected state of the folded box. The course of the closure folding lines produces tension in the erected folded box which keeps the folded box closed.
[0014] A further preferred embodiment of the blank is characterized in that the distance between the closure folding lines and the associated edge of the respective closing section increases linearly starting from the side wall sections to the inside and to the outside. The resulting straight closure folding lines are advantageous in that they are easy to produce.
[0015] A further preferred embodiment of the blank is characterized in that the closure folding lines are curved to the inside like a circular arc, relative to the blank. Experiments carried out within the scope of the present invention showed that a slightly curved shape of the closure folding lines is particularly advantageous. The curvature of the closure folding lines ensures that the closing sections snap in when a folded box produced from the blank, is closed.
[0016] A further preferred embodiment of the blank is characterized in that the distance between the closure folding lines and the associated edge of the respective closing section is constant in the region within the two side wall sections and increases to the outside in the regions outside of the two side wall sections. The closing sections are thereby pretensioned in the closing direction in the assembled state of the folded box. Pretensioning ensures snapping in or convergence of the closing sections when the folded box is closed.
[0017] A further preferred embodiment of the blank is characterized in that on the side, opposite to the continuous folding line, of one of the side wall sections, a flap is formed on the associated principal wall section by a further folding line which is disposed parallel to the continuous folding line. The flap servers to connect the two wall sections to each other.
[0018] A further preferred embodiment of the blank is characterized in that the continuous folding line and the further folding line substantially coincide when the folded box is assembled. This ensures folding of the blank even when the two wall sections are connected to each other on two sides to form the tubular body.
[0019] A further preferred embodiment of the blank is characterized in that an outlet funnel is provided on one of the tapering ends of the side wall section. The outlet funnel serves for pouring out a fluid located in the closed folded box. The outlet funnel may, of course, also be used for filling in a fluid depending on size and shape.
[0020] A further preferred embodiment of the blank is characterized in that the outlet funnel is formed by means of five outlet funnel folding lines which are formed on the tapering end of the side wall section. The five folding lines ensure repeated opening and closing of the outlet funnel when the folded box is erected.
[0021] A further preferred embodiment of the blank is characterized in that the distance between the outlet funnel folding lines from each other decreases to the associated tapering end of the side wall section which guarantees funnel-shaped widening of the outlet funnel to the outside.
[0022] A further preferred embodiment of the blank is characterized in that a triangular projection with tip pointing to the outside is disposed in the region of the outlet funnel on the two associated closing sections. The triangular projection ensures, in connection with a centrally disposed outlet funnel folding line, precise pouring out.
[0023] A further preferred embodiment of the blank is characterized in that a closing flap is provided on the outside of the outlet funnel which can be separated from the two bordering closing sections by at least one perforation line. The closing flap serves to keep the outlet funnel closed. When the closing flap is removed, the outlet funnel can be opened.
[0024] The above-stated object is achieved in a folded box of a one-piece blank, in that the folded box has one body in the assembled state which tapers to the outside with two ends and has a substantially rectangular cross-section in the center. The shape of the folded box therefore resembles a plastic bag welded at the ends. A plastic bag obtains its shape by the solid content. The shape of the inventive folded box is determined by the folding lines. The inventive folded box is advantageous in that it can be supplied in a flat state. Moreover, it has its own body whose size and shape are determined without product, and a functioning closing unit. It can be erected manually and also by a machine. The inventive blank can be processed on conventional production machines without additional equipment. The folded boxes can be produced in many variants, e.g. as carrier package or with particular features such as closing means and tearing techniques.
[0025] A preferred embodiment of the folded box is characterized in that the body has two outwardly tapering side wall sections. The side wall sections provide the erected folded box with stability. Shaping of the side wall sections provides the erected folded box with e.g. the shape of a right parallelepiped with two opposite tapering ends.
[0026] A further preferred embodiment of the folded box is characterized in that two flat closing regions are formed on the outwardly tapering ends of the body. The flat closing regions permit fluid-tight closure of the folded box e.g. by welding. The closing regions also permit manual closure and re-opening of the folded box. The specific arrangement of the closure folding lines ensures snapping in and holding together of the closure regions without having to use other techniques or auxiliary means. The closing regions may also be sealed or glued.
[0027] A further preferred embodiment of the folded box is characterized in that the principal and side wall sections are mutually separated from each other only by a folding line. This single folding line between each principal wall section and the joining side wall section provides the erected folded box with its defined shape.
[0028] A further preferred embodiment of the folded box is characterized in that a cut is provided in at least one of the closing sections into which a flap can engage which is formed on the closing section which abuts the closing section with the cut when the folded box is erected. The flap and the cut facilitate closing of the erected folded box. When the flap engages in the associated cut, the two abutting closing sections are fixed relative to each other.
[0029] This closing mechanism is advantageous in that it is easy to realize since no additional fastening means are required and repeated opening and closing of the folded box is ensured.
[0030] A further preferred embodiment of the folded box is characterized in that the cut has the shape of a circular arc which is curved inwardly relative to the blank. This shape of the cut has proven to be particularly advantageous in practice.
[0031] A further preferred embodiment of the folded box is characterized in that the flap is formed by a cut which has the shape of a circular arc which is curved inwardly relative to the blank. This shape of the cuts ensures simple closing of the folded box when it is erected.
[0032] A further preferred embodiment of the folded box is characterized in that in at least one closing section at least one flap is formed which abuts on an adhesive surface, formed on an abutting closing section and covered by the flap, when the folded box is erected. As long as the foldable flap abuts the adhesive surface, the associated closing sections also abut each other and the folded box is closed. When the flap is folded, the connection to the closing section with adhesive surface is released and the abutting closing sections can be removed from each other.
[0033] A further preferred embodiment of the folded box is characterized in that the adhesive surface is delimited by a groove. The groove extends preferably only in an upper layer of the blank. The groove ensures defined pulling out of the upper blank layer which provides on the one hand that the original seal cannot be reproduced. On the other hand, the outer side of the closing section provided with the adhesive surface remains untouched also after removal of the upper blank layer, i.e. the optical impression is not impaired.
[0034] One substantial advantage of the inventive folded box consists in that a one-piece, square blank can be used. This permits production of folded boxes without new technical equipment. The simple and quick closing of the folded box due to the distance between the closure folding lines and the associated edge of the closing sections ensures that the folded box can be made flat again after use.
[0035] In the flat state, the folded box can either be supplied to a recycling cycle or be manually or mechanically erected again. The possibility of welding or sealing the closing sections of the folded box is important in particular for food and in general for powdery and liquid products. The closing sections can also be formed as handles or have a so-called Euro hole.
[0036] Due to the particularly simple handling, the inventive folded box is particularly well suited as gift wrapping, e.g. for dessous, accessories or jewellery. The folded box is also suitable for accommodating sweets, household goods, office equipment or food. Since the folded box can be tightly sealed, it is also suited to accommodate powder and liquids. The inventive folded box finally has a particularly pleasant design when it is erected. The pleasant design and the flatly tapering closing flaps make the folded box suitable also for display in a decoration wall.
[0037] In the embodiment with the slightly curved closure folding lines, a tension is generated which ensures snapping in of the closing sections when the folded box is manually closed. The outlet funnel integrated in the closing sections can be closed again after opening thereby protecting the content of the folded box from vermins and dirt also after opening and handling is moreover facilitated.
[0038] The inventive blank can be provided with pre-glued points or be printed or punched by a machine and erected on a machine. In the latter case, the folding lines can also be eliminated. The package becomes more stable thereby and the package has no disturbing lines. The closing region can be displaced depending on the optics of the printed image.
[0039] Further advantages, features and details of the invention can be extracted from the following description which describes in detail different embodiments with reference to the drawing. The features mentioned in the claims and in the description may be essential to the invention either individually or collectively in arbitrary combination.
BRIEF DESCRIPTION OF THE DRAWING
[0040] [0040]FIG. 1 shows a top view onto a blank for a folded box according to a first embodiment;
[0041] [0041]FIG. 2 shows a top view onto a blank for a folded box according to a second embodiment with elliptical side wall sections;
[0042] [0042]FIG. 3 shows a top view onto a blank for a folded box according to a third embodiment;
[0043] [0043]FIG. 4 shows a perspective view of an erected folded box with handle and a window;
[0044] [0044]FIG. 5 shows a perspective view of an erected folded box with reclosable opening flap;
[0045] [0045]FIG. 6 shows a perspective view of an erected folded box with flap closure;
[0046] [0046]FIG. 7 shows a perspective view of an erected folded box with a breaking line in the center;
[0047] [0047]FIG. 8 shows a top view onto a blank for a folded box according to a fourth embodiment with circular arc-shaped curved closure folding lines;
[0048] [0048]FIG. 9 shows a top view onto a blank for a folded box according to a fifth embodiment with straight folding lines;
[0049] [0049]FIG. 10 shows a top view onto a blank for a folded box according to a sixth embodiment with an outlet funnel;
[0050] [0050]FIG. 11 shows a perspective view of an erected folded box with an outlet funnel as shown in the blank of FIG. 10;
[0051] [0051]FIG. 12 shows a blank for a folded box according to a seventh embodiment with a closing flap; and
[0052] [0052]FIG. 13 shows a blank for a folded box according to an eighth embodiment with an original seal.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0053] [0053]FIG. 1 shows a top view of a rectangular blank 1 . A plurality of folding lines is disposed on the blank 1 . The folding lines may be folds, grooves, scratches or perforations. The folding lines form defined sections when the blank 1 is erected to a folded box.
[0054] The blank 1 comprises a principal section 5 having two partial sections 3 and 4 , and a principal section 9 having two partial sections 7 and 8 . The principal sections 5 and 9 are separated from each other by a principal folding line 10 . The principal sections 5 and 9 have the shape of rectangles abutting each other along their longitudinal sides.
[0055] The side wall section 11 is formed by two side wall folding lines 14 and 15 which extend parallel to each other in the central region and taper towards each other at the ends. At the tapering ends, the side wall folding lines 14 and 15 merge into terminating folding lines 22 and 23 . The side wall section 12 is delimited in the same fashion by two side wall folding lines 16 and 17 which extend parallel to each other in the center and merge at the end into terminating folding lines 24 and 25 .
[0056] The side wall section 11 is disposed between the partial sections 3 and 4 of the principal section 5 . The side wall section 12 is disposed between the partial sections 7 and 8 of the principal section 9 . The partial section 3 is delimited at two opposite sides by two closure folding lines 26 and 29 . The partial section 4 is delimited on two opposite sides by two closure folding lines 27 and 28 . The partial section 7 is delimited on two opposite sides by two closure folding lines 30 and 33 . The partial section 8 is delimited on two opposite sides by two closure folding lines 31 and 32 .
[0057] The partial section 8 is also delimited by the side wall folding line 17 , the closure folding lines 31 , 32 and a terminating edge 35 of the blank 1 . The partial section 7 is delimited by the principal folding line 10 , the closure folding lines 30 , 33 and the side wall folding line 16 . The partial section 4 is delimited by the principal folding line 10 , the closure folding lines 27 , 28 and the side wall folding line 15 . The partial section 3 is delimited by the side wall folding line 14 , the closure folding lines 26 , 29 and a terminating folding line 37 .
[0058] The terminating folding line 37 delimits a flap 39 on the side facing away from the partial section 3 . The flap 39 is divided by perpendicular cuts 71 and 72 into three flap sections 39 a , 39 b and 39 c . The flap 39 serves to connect the principal sections 5 and 9 to each other. When the principal sections 5 and 9 are connected to each other through the flap 39 , the terminating edge 35 of the blank 1 abuts the terminating folding line 37 thereby providing the blank 1 with a tubular shape when it is erected.
[0059] Eight closing sections 41 , 42 , 45 , 46 and 44 , 43 , 48 , 47 are formed on the longitudinal sides of the blank 1 . The closing sections 41 to 44 are formed on the principal section 5 and the closing sections 45 to 47 are formed on the principal section 9 . The closing section 41 is delimited by the longitudinal edge of the blank 1 , the terminating folding line 37 , the closure folding line 29 and the terminating folding line 22 .
[0060] The closing section 42 is delimited by the longitudinal edge of the blank 1 , the terminating folding line 22 , the closure folding line 28 and the principal folding line 10 . The closing section 43 is delimited by a longitudinal edge of the blank 1 , the terminating folding line 23 , the closure folding line 27 and the principal folding line 10 . The closing section 44 is delimited by the longitudinal edge of the blank 1 , the terminating folding line 23 , the closure folding line 26 and the terminating folding line 37 .
[0061] The closure section 45 is delimited by a longitudinal edge of the blank 1 , the principal folding line 10 , the closure folding line 33 and the terminating folding line 24 . The closing section 46 is delimited by the longitudinal edge of the blank 1 , the terminating folding line 24 , the closure folding line 32 and the terminating edge 35 of the blank 1 . The closure section 47 is delimited by a longitudinal edge of the blank 1 , the terminating folding line 25 , the closure folding line 31 and the terminating edge 35 of the blank 1 . The closing section 48 is delimited by the longitudinal edge of the blank 1 , the principal folding line 10 , the closure folding line 30 and the terminating folding line 25 .
[0062] The closure folding lines 27 , 30 and 28 , 33 extend parallel to the longitudinal edges of the blank 1 . The closure folding lines 26 , 29 and 31 , 32 extend non-parallel to the longitudinal edges of the blank 1 . Dotted lines 51 , 52 , 53 and 54 indicate that the distance between the closure folding lines 26 , 29 and 31 , 32 and the associated longitudinal edges of the blank 1 increases slightly providing snapping in of the abutting closing section when the folded box is closed. Moreover, the abutting closing sections are held in abutment when the folded box is closed.
[0063] For assembling the inventive folded box, the flap 39 formed on the principal section 5 is glued to the principal section 9 such that the terminating edge 35 coincides with the terminating folding line 37 which produces a flat configuration which can be erected to a tubular body with rectangular cross-section.
[0064] When the folded box is erected, the side wall sections 11 and 12 produce a rectangular cross-section in the center of the folded box. When the folded box is erected, the closing sections 41 and 42 , 43 and 44 , 45 and 46 , 47 and 48 abut each other. The folded box can be closed with two fingers pressing together the closing sections in the region of the terminating folding lines 22 , 24 and 23 , 25 .
[0065] In the closed state, the abutting closing sections can be welded, glued or fastened to each other in another fashion. The inventive design of the closure folding lines 26 , 29 , 31 and 32 does not necessarily require mounting of the abutting closing sections to each other since the abutting closing sections are held together by the inventive design of the closure folding lines 26 , 29 , 31 and 32 . When the abutting closing sections are not mounted to each other, the erected folded box can be easily opened by moving apart the abutting closing sections. The folded box can be easily collapsed again.
[0066] In the embodiment shown in FIG. 1, the side wall folding lines 14 , 15 and 16 , 17 of the side wall sections 11 and 12 extend largely parallel to each other. The side wall folding lines 14 and 15 , 16 and 17 meet only at the ends of the side wall sections 11 and 12 .
[0067] The embodiments shown in FIGS. 2 and 3 resemble the embodiment shown in FIG. 1. Identical parts have identical reference numerals such that reference is made to FIG. 1. Below, only the differences between the individual embodiments are mentioned.
[0068] In the embodiment of the blank 1 shown in FIG. 2, the side wall folding lines 14 ′, 15 ′ and 16 ′, 17 ′ which form the side wall sections 11 ′ and 12 ′ are not disposed parallel to each other but elliptical. The erected folded box therefore has an elliptical cross-section between abutting closing sections.
[0069] In the embodiment of the blank 1 shown in FIG. 3, the side wall folding lines 14 ″, 15 ″ and 16 ″, 17 ″ of the side wall sections 11 ″ and 12 ″ are disposed parallel to each other and form one rectangle each with two folding lines 20 . Two folding lines 18 and 19 extend from the points of intersection between the folding lines 20 and the side wall folding lines 14 ″, 15 ″ and 16 ″, 17 ″ to the terminating folding lines 22 to 25 . The folding lines 18 , 19 and 20 each form a triangle at the end of the side wall sections 11 and 12 . The tips of the triangles extend to the outside. The terminating folding lines 22 to 25 extend from the tips of the triangles.
[0070] In all three embodiments shown in FIGS. 1 to 3 , five folding lines each intersect or meet at the tips of the tapering side wall sections 11 and 12 . This is an essential feature of the present invention. This feature obtains that the inventive folded box can be erected and collapsed again in a simple fashion.
[0071] In the embodiments shown in FIGS. 1 and 2, firstly the folding lines 14 , 15 , 28 , 22 and 29 , secondly the folding lines 14 , 15 , 26 , 23 and 43 , thirdly the folding lines 16 , 17 , 31 , 25 and 30 and fourthly the folding lines 16 , 17 , 32 , 24 and 33 merge in one point. In the embodiment shown in FIG. 3, firstly the folding lines 18 , 19 , 28 , 22 and 29 , secondly the folding lines 18 , 19 , 27 , 23 and 26 , thirdly the folding lines 18 , 19 , 31 , 25 and 30 and fourthly the folding lines 18 , 19 , 32 , 24 and 33 merge in one point.
[0072] [0072]FIG. 4 shows a perspective view of an erected folded box in accordance with a fourth embodiment. As shown in FIG. 4 the partial sections 4 and 7 can be connected to each other in one piece in machine blanks without forming a folding line between them. The same is true for the closing sections 42 and 45 . A common opening 55 is formed in the closing sections 42 and 45 which serves as handle. The opening 55 may also have the shape of a Euro hole on which the erected folded boxes can be hung.
[0073] The embodiment shown in FIG. 5 has an opening which can be re-sealed by an opening flap 58 . The opening provides access to the erected folded box from the outside without having to open the closing sections 42 , 45 or 43 , 48 .
[0074] In the embodiment shown in FIG. 6, the closing sections 42 and 45 are held in abutment on the associated closing sections by a locking flap 60 . When closing, the locking flap 60 is folded from the position shown in FIG. 6 such that a projection 62 formed in the locking flap 60 at the end engages in a recess 63 . At the end of the closing sections 43 and 48 , a perforation line 61 is provided for opening the folded box. The perforation line 61 is formed between the closing sections 43 , 48 and a section 65 in which the abutting closing sections are glued to each other. The folded box can be opened by tearing or cutting off the section 65 .
[0075] In the embodiment of FIG. 7, the center of the erected folded box has a perforation line 64 which serves as breaking line for opening the folded box. The closing sections 43 and 48 are held in abutment on their associated closing sections by a circular punching 66 . The closing sections 42 and 45 are held in abutment on their associated closing sections by grooves 68 and 69 . It is of course also possible to combine different types of closure.
[0076] The embodiments shown in FIGS. 8, 9 and 10 , resemble the embodiment of FIG. 1. Identical parts have identical reference numerals such that reference is made to the description of FIG. 1. Only the differences between the individual embodiments are mentioned below.
[0077] In the embodiment shown in FIG. 8, the closure folding lines 26 ′ to 33 ′ are slightly curved to the inside. The slight curvature results in that the distance between the closure folding lines 26 ′ to 29 ′ and the associated outer edge of the respective closing section is not constant but decreases to the tips of the side wall section 11 . The same is true for the closure folding lines 30 ′ to 33 ′. This course of the closure folding lines 26 ′ to 33 ′ obtains that the width of the closing sections 41 to 44 and 45 to 48 decreases towards the terminating folding lines 22 , 23 or 24 , 25 .
[0078] In the embodiment shown in FIG. 9, the closure folding lines 26 ″ to 33 ″ are not slightly curved but straight. The distance between the closure folding lines 29 ″ to 33 ″ and the associated edge of the respective closing sections decreases towards the associated tips of the respective side wall sections 11 , 12 as shown in the embodiment of FIG. 8. The width of the closing sections 41 to 48 is thereby decreased towards the respective terminating folding lines 22 to 25 .
[0079] In the embodiment shown in FIG. 10, the distance between the closure folding lines 26 a to 33 a and the associated edge of the respective closure sections is constant. Therefore, the closing sections have a constant width. For closing, the closing sections 42 a , 43 , 45 and 48 have adhesive surfaces 85 and 86 . The adhesive surfaces 85 and 86 serve to glue the closing sections which come into abutment when the erected folded box is closed. Gluing of the abutting closing sections permits a guarantee closure of the inventive folded box.
[0080] The corresponding closing sections may be sealed to each other instead of glued. For sealing, a lacquer to be applied to the closing sections is heated, wherein the closing sections are held in mutual abutment by means of pressure jaws. In a subsequent cooling process, the closing sections are permanently joined.
[0081] Two outlet funnel folding lines 74 and 75 are formed in the closing section 41 a . The outlet funnel folding lines 74 and 75 intersect in a point 90 which is disposed on the side wall folding line 14 slightly separated from the tapering end 92 of the side wall section 11 . The outlet funnel folding line 75 is disposed at a more acute angle to the terminating folding line 22 a which forms a further outlet funnel folding line, than the outlet funnel folding line 74 .
[0082] The outlet funnel folding lines 76 and 77 are axially symmetrical to the outlet funnel folding lines 75 , 74 relative to the terminating folding line 22 a or outlet folding line. The outlet funnel folding lines 76 and 77 intersect at a point 91 which is disposed at the same level of the side wall section 11 as the point of intersection 90 of the outlet funnel folding lines 74 and 75 .
[0083] The points of intersection 90 and 91 are connected to each other via an outlet funnel folding line 93 which is slightly curved away from the tapering end 92 . The outlet funnel folding line 93 increases the opening cross-section of the outlet funnel.
[0084] A triangular projection 79 joins the region of the closing sections 41 a disposed between the outlet funnel folding lines 75 and 76 . This triangular projection 79 forms an outlet channel when the outlet funnel is opened.
[0085] A closing flap 80 joins the closing sections 41 a , 42 a and the triangular projection 79 . The closing flap 80 is connected via perforated lines 81 , 82 , 83 and 84 to the closing sections 41 a , 42 a and the triangular projection 79 . An adhesive surface 87 is formed on the closing flap 80 , which connects the two halves of the closing flap 80 , formed by the terminating folding line 22 a when the outlet funnel is closed. For opening the outlet funnel, the closing flap 80 must be torn off. The outlet funnel can then be opened by moving the outlet funnel folding lines 75 and 76 away from each other.
[0086] [0086]FIG. 11 shows a perspective view of an erected folded box from a blank similar to the blank of FIG. 10. The closing sections 41 a and 46 have a recess 88 in the form of a so-called Euro hole.
[0087] [0087]FIG. 12 shows a blank similar to the blank of FIG. 1. Identical parts have the same reference numerals plus 100 such that reference is made to the description of FIG. 1. In the following, only the differences between the individual embodiments are mentioned. The flap 139 comprises in the embodiment shown in FIG. 12 three separate flaps 139 a , 139 b and 139 c which have different designs. The flap 139 a is based on a partial section 103 and has the shape of a longitudinal rectangle which has two inclined sides. The flaps 139 b and 139 c are each based on the associated closing section 141 and 144 and have the shape of rectangles with one inclined side and a U-shaped section.
[0088] Moreover, in the embodiment of FIG. 12, a circular arc-shaped cut 201 , 211 is provided in the closing sections 142 and 143 which is curved towards the associated partial section 104 . The ends 202 , 203 and 212 , 213 of the cuts 201 and 211 are also curved in a circular arc shape but in opposite directions to the associated cut. Moreover, the closing sections 146 and 147 have circular cuts 205 and 215 which are curved towards the associated partial section 108 . The curvature of the cuts 205 and 215 is slightly stronger than the curvature of the cuts 201 and 211 . The ends 206 , 207 and 216 , 217 of the cuts 205 and 215 are also curved in the shape of a circular arc but in the opposite direction to the cuts 205 and 215 .
[0089] The cuts 205 and 215 form flaps 208 and 218 whose contour is more curved than the cuts 201 and 211 . This ensures that the flaps 208 and 218 can engage well in the cuts 210 and 211 when the closing sections 142 and 146 or 143 and 147 come into abutment. Folding lines 204 and 214 which extend straight between the ends of the cuts 201 and 211 ensure easy opening of the cuts 201 and 211 .
[0090] [0090]FIG. 13 shows a blank which is similar to the blank of FIG. 1. Identical parts have the same reference numerals plus 300 such that reference is made to the description of FIG. 1. Only the differences between the individual embodiments are described below.
[0091] In the embodiment shown in FIG. 13, the partial sections 304 and 307 have a common window 401 which can be filled or backed with a transparent plastic foil. The window 401 serves to make the content of the erected folded box visible from the outside.
[0092] In the region of the point of intersection between the closing sections 342 and 345 , a flap 405 is cut out which is connected to the principal wall section 305 via a folding line. In the same way, a disposed flap 406 is cut out between the closing sections 343 and 348 which is also connected to the main wall section 305 via a folding line. The flaps 405 and 406 come in abutment on adhesive layers 412 and 413 provided in the connecting region between the flap 339 b and the closing section 241 and the flap 339 c and the closing section 344 , when the folded box is erected. The adhesive surfaces 412 and 413 are delimited by grooves 414 and 415 which extend only in the upper layer of the blank 301 .
[0093] When the flaps 405 and 406 abut on the associated adhesive surfaces 412 and 413 after erection of the folded box, the folded box is originally sealed. When the flaps 405 and 406 are folded, the upper layers of the blank 301 adhere to the flaps 405 and 406 within the grooves 414 and 415 together with the adhesive layers 412 and 413 . Renewed closing of the folded boxes with the flaps 405 and 406 is no longer possible.
[0094] The coinciding design of the closing sections provides among other thing the advantage that a plurality of in particular simple sealing possibilities can be applied. The closing sections can also be designed having different functions e.g. as Euro hole, pouring means, apportioning means or handles. The closing sections can also be provided with a decorative contour punching.
[0095] The inventive folded box combines the advantages of a plurality of closing possibilities, simple production, simple handling and reduced machine and tool costs in all regions. It also offers a plurality of possible applications and is suited for package anything.
[0096] The transition from the package body to the closing sections may be formed by a displaced or curved line whereby tension is generated in the erected state through which the closing sections are held in mutual abutment. Simple manual securing is possible through two circular arc-shaped cuts.
[0097] For presents, simple geometrical shapes can be punched out in the closing sections through which e.g. a cord or ribbon can be guided to close the folded box.
[0098] An original seal may be provided by connecting the abutting closing sections mechanically to each other by a hot setting adhesion point. This ensures that opening of the package will always damage it to prevent undesired manipulation and theft of the contents of the packing.
[0099] When the closing sections are rigidly connected by sealing, even liquid media can be kept in the erected folded box. The material of the blank must, of course, be suitable for accommodating the liquid or be provided with a corresponding coating.
[0100] It is pointed out that the principal folding line 10 and/or the terminating folding line 37 may be omitted in all embodiments depending on the production method. | The invention relates to a folded box comprising two principal wall sections ( 5, 9 ), which are joined on one side and can be interconnected on the opposing side, for example by means of a flap ( 39 ), to form a substantially tubular body, whose ends can be sealed. To reduce production costs, a lateral wall section ( 11, 12 ), with ends that taper to a point, is configured in at least one of the two principal wall sections ( 5, 9 ). | 1 |
BACKGROUND OF THE INVENTION
This invention relates generally to apparatus for dispensing and combining metered quantities of different fluids and, more specifically, to a machine for selectively dispensing colorants used to formulate paints of various color.
In the interest of limiting costly inventories, most retail stores formulate many paint colors at the time of purchase rather than stocking all available colors. The formulation is accomplished by adding specified quantities of colorant tints to a white base paint so as to create the specific color desired. Typically, paints are formulated with apparatus including a plurality of colorant filled containers and pumping mechanisms for withdrawing predetermined quantities therefrom. In the simplest machines of this type, a can filled with the base paint is sequentially moved to each desired colorant container and its individual pump is actuated to withdraw the desired quantity of fluid colorant. A more efficient machine of this type includes a rotary turntable on which the colorant containers are mounted and which is used to sequentially move each colorant container required for the formulation to a given discharge area occupied by the base paint filled can. Although such machines are relatively simple and inexpensive and function satisfactorily for many applications, they exhibit the disadvantage of requiring a substantial amount of attention by an operator thereby adding significiant labor cost to the paint sold. Conversely, there exist intricate automatic paint colorant machines that will dispense the various tints required for a given formulation in response to the mere insertion of a coded punch card selected by an operator. Although drastically reducing required operator time these machines are too expensive for practical use in most retail outlets and also suffer breakdowns that require complex repairs and often render them dysfunctional for extended periods of time.
The object of this invention, therefore, is to provide a semi-automatic paint colorant dispensing machine that limits required operator attention and is in addition reliable and relatively inexpensive.
SUMMARY OF THE INVENTION
The machine according to the present invention includes a plurality of containers for a variety of paint colorants and a plurality of measuring receptacles, one connected for fluid communication with each of the containers. A cyclic pumping system simultaneously pumps metered volumes of colorant into predetermined measuring receptacles from their associated containers during a withdrawal cycle and then dispenses the metered volumes during a discharge cycle. Adjustment of selector mechanisms associated with each measuring receptacle provides the exact quantities of colorant required to formulate a specific volume of a desired paint color. A cycle timer establishes a uniform time period for each of the sequential withdrawal and dispensing cycles regardless of the colorant quantities being dispensed and a sequence timer can be preset to provide the number of sequential withdrawal and dispensing cycles required to formulate paint volumes that are a given multiple of the specific volume.
In a preferred embodiment of the invention the pumping system comprises a power piston and cylinder assembly associated with each of the containers and the receptacles are formed by dispensing cylinders having outlets communicating with nozzles in a nested array. Dispensing pistons in the dispensing cylinders are mechanically coupled to the power pistons so as to be reciprocative therewith. The selector mechanisms comprise adjustable stops that selectively limit the strokes of the mechanically coupled together power and dispensing pistons thereby establishing desired measuring volumes in the dispensing cylinders. These volumes are filled during withdrawal strokes by the power piston and the resultant measured volumes of colorant are discharged from the nested nozzles during the power pistons' discharge strokes. The tandem arrangement of power and dispensing cylinders greatly simplifies the automatic measurement and dispensing of fluid volumes.
According to one feature of the invention a lost motion coupling allows a small initial movement by each power piston that is not experienced by its associated dispensing piston. The lost motion allows a dispensing piston to remain motionless in the event that the applied hydraulic force causes a slight elongation of an associated power cylinder and a resultant inadvertent motion of a fully stopped power piston. In the absence of the lost motion, such inadvertent motion of a power piston could prompt the discharge of a small quantity of undesired colorant. To accommodate the lost motion, an elongated scale forming the selector is provided with a plurality of uniformly spaced graduations representing given increments of movement by the power piston and an initial pair of more widely spaced graduations represent the given increment of movement plus the lost motion of the power piston.
DESCRIPTION OF THE DRAWINGS
These and other objects and features of the invention will become more apparent upon a perusal of the following description taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a schematic drawing illustrating one module of a paint colorant dispensing machine according to the invention;
FIG. 2 is a schematic circuit diagram of an electrical control system for the machine shown in FIG. 1;
FIG. 3 is a side elevational view of a discharge assembly for a machine having a plurality of the dispenser modules shown in FIG. 1;
FIG. 4 is a cross-sectional view taken along lines 4--4 in FIG. 3;
FIG. 5 is a detailed cross-sectional view of the tandem power and dispensing cylinders shown in FIG. 1; and
FIG. 6 is a partial sectional view taken long lines 6--6 in FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1 there is shown a dispensing module 11 including a tandemly arranged power and dispensing cylinder assembly 12. The assembly 12 includes an upper power cylinder 13 and a lower dispensing cylinder 14 separated by a divider wall 15. Reciprocatively mounted in the power cylinder 13 is a power piston 16 coupled to a dispensing piston 17 in the cylinder 14 by a connecting rod 18 that extends through the divider wall 15. Also slidably received within the power cylinder 13 is a selector scale 19 terminating at its lower end with a shoulder stop 21 that limits upward movement of the power piston 16. Further details of the power and dispensing cylinder assembly 12 are described below in connection with FIGS. 5 and 6.
The dispensing cylinder 14 is connected for fluid communication with a container 22 by an inlet tube 23 including an inlet check valve 24. When in use the container 22 is filled with a fluid colorant of the type employed for tinting paints. The fluid medium retained by the container 22 can be agitated by a stirrer 25 driven by a motor 26. Also in fluid communication with the dispensing cylinder 14 is an outlet tube 27 that includes an outlet check valve 28 and terminates with a discharge nozzle 29. It should be noted that a complete colorant dispensing machine according to the invention includes a plurality of the dispensing modules 11, one for each colorant desired. The discharge nozzles 29 for all such modules are nested in a common discharge area as described hereinafter in connection with FIGS. 3 and 4.
A single hydraulically powered pumping system 31 powers dispensing operations for all the modules 11 of a machine. The system 31 includes an hydraulic pump 32 that is driven by a motor 33. The pump 32 draws hydraulic fluid from a reservoir 34 and is bypassed by a relief valve 35. Receiving hydraulic fluid supplied by the pump 32 is a four-way valve 36 that is controlled by a solenoid 37. A tube 38 permits circulation of hydraulic fluid between the valve 36 and the lower end of the power cylinder 13 while a tube 39 permits circulation of fluid between the valve 36 and the upper end of the dispensing cylinder 14. The hydraulic circulation system is completed by a return tube 41 that extends between the exhaust outlet of the valve 36 and the reservoir 34. As described in greater detail below, the module 11 selectively withdraws predetermined volumes of colorant from the container 22 and discharges those volumes out of the nozzle 29. The precise volumes discharged are controlled by the selector limit means 19 which also is described in greater detail below.
Referring now to FIG. 2 there is shown an electrical system 43 for controlling the operation of the dispensing module 11 shown in FIG. 1. The system 43 has a pair of terminals 44, 45 for connection to a suitable source of electrical power and a safety switch 46 for energizing the system. Connected to the terminals 44 and 45 is a two-pole on-off switch 47, having one on position that energizes the stirring motors of all modules in the system and a second on position that provides power to the bus lines 48 and 49 of the circuit 43. Connected in parallel in the line 48 are a momentary start-up switch 51 controlled by a sequence timer 52 and a switch contact 53 controlled by a cycle timer 54. The sequence control timer 52 includes a synchronous clock timer 55 that is connected across the lines 48 and 49 and can be set to provide a given period of actuation of a clutch 56 that maintains the switch contact 51 in a closed position. Also connected between the lines 48 and 49 by a switch contact 57 is the solenoid 37 that controls the four-way valve 36 shown in FIG. 1. The cycle timer 54 also has a synchronous clock timer 58 connected between the lines 48 and 49 and mechanically coupled to a pair of timing cams 59 and 61. The cam 59 is operatively coupled to the switch contact 53 which it maintains closed during the major portion of each revolution of the clock timer 58 while the cam 61 is operatively coupled to the switch contact 57 which it maintains in closed position for approximately one half of each revolution of the clock timer 58. Also connected across the lines 48 and 49 is an indicator light 62 and the motor 33 for the hydraulic pump 32 shown in FIG. 1.
When using the machine an operator examines an instruction manual to determine the amounts and types of colorant required to formulate a given amount of a desired paint color. Next, the module associated with each required colorant is set to provide the necessary quantity. Assuming, for example, that the colorant retained by the container 22 (FIG. 1) is required for the formulation, the selector rod 19 is set so as to locate the stop 21 in a position that will limit the stroke of the power piston 16 to a given length. This in turn determines the stroke length of the directly coupled dispensing piston 17 and thereby establishes which portion of the dispensing cylinder 14 will function as a measuring receptacle during a dispensing cycle. After closure of the switch 46 (FIG. 2), in a manner described below, the switches 47 and 51 are closed to simultaneously energize the timers 55 and 58, the signal light 62 and the pump motor 33. Energization of the timer 55 actuates the clutch 56 to maintain the switch contact 51 closed for the predetermined time period for which the timer 55 has been set. At the same time energization of the motor 33 activates the hydraulic pump 32 (FIG. 1) which pumps hydraulic fluid through the hydraulic system 31. In its initial position the valve 36 conveys hydraulic fluid through the tube 38 into the power cylinder 13 producing a withdrawal stroke in which the power piston 16 is forced up against the stop 21. Corresponding upward movement of the dispensing piston 17 creates in the dispensing cylinder 14 a vacuum that draws fluid colorant from the container 22 through the feed line 23 and the inlet check valve 24. After one-half revolution of the clock timer 58 (FIG. 2), the cam 61 closes the switch contact 57 to energize the solenoid 37. This actuates the valve 36 into a position connecting the inlet to the tube 39 and the tube 38 to the exhaust line 41. Consequently hydraulic fluid is pumped into the dispensing cylinder 14 forcing the dispensing piston 17 downwardly to expel the previously drawn-in colorant through the outlet valve 28 and into the tube 27. This produces from the nozzle 29 the discharge of a predetermined volume of colorant established by the original setting of the selector rod 19. During this dispensing cycle by the module 11 all other modules associated with required colorants simultaneously dispense volumes determined by the settings of their selector rods. It should be noted that the clock timer 58 is selected so as to provide cycle periods of sufficient length to accommodate the maximum possible strokes of the power and dispensing pistons 16 and 17.
Assuming that only a single dispensing cycle is desired the sequence timer 55 would not have been set to delay opening of momentary start-up switch 51. Consequently upon completion of a single revolution by the timer 58, the cam 59 will have reached its initial position to open the switch contact 53 to thereby deenergize the circuit 43. However, if the quantity of paint being formulated is a certain multiple of the given volume for which the selector settings were made, an appropriate number of additional dispensing cycles can be provided automatically by selective adjustment of the sequence timer 52. For example, if the instruction manual provides selector settings for formulating a pint of paint, eight dispensing cycles would be required to formulate a gallon of paint. Accordingly, the sequence timer 52 is set for a time period equal to the period required for seven and one-half revolutions by the cycle timer 58. In this case, a complete revolution of the cycle timer 58 does not deenergize the circuit 43 in that the sequence timer 55 maintains the clutch 56 activated to hold closed the switch contacts 51. Accordingly, the cycle timer 58 continues to rotate and produce sequential dispensing cycles in the manner described above. Only after seven and one-half dispensing cycles have been completed does the sequence timer 52 de-activate the clutch 56 and open the contacts 51. After the desired eight dispensing cycles the cam 59 opens the switch 53 to terminate operation. Obviously any other desired number of dispensing cycles can be automatically obtained by appropriate settings of the sequence timer 55. Furthermore, once the machine has been set to formulate a given sized can of a desired color, additional cans can be prepared by merely re-activating the start switch 51.
Referring now to FIGS. 3 and 4 there is shown an assembly for accommodating collection of the fluid colorants dispensed by a plurality of the modules 11 shown in FIG. 1. Extending from a base 71 are a pair of support brackets 72 with lower edges defined by outwardly extending flanges 73. Supported between the brackets 72 is a molded nest 74 having an array of bores 75 for receiving the tubes 27 from the modules 11. The nest 74 includes a plurality of resilient cups 29, one located at the bottom of each of the bores 75. Each of the resilient cups 29 include a pair of separable flaps 31 that can be forced apart by fluid pressure to provide nozzle openings from the tubes 27. Slidably retained by the flanges 73 is a cup 76 that supports a transverse wire 77 aligned with the bottom edges of the nozzle cups 29. Also supported by the bottom surface of the cup 76 is a downwardly extending bracket 78. Located below the nest 74 and removably retained by the base 71 is a shelf 79 for accommodating a paint can 81. Also mounted on the base 71 is the switch 46 shown in FIG. 2 and having an actuator arm 82.
When preparing for a dispensing operation of the type described above, an opened paint can 81 is placed upon the shelf 79 and slid rearwardly to the position directly below the nested nozzles 29 as shown by dotted lines in FIG. 3. During its rear movement onto the shelf 79, the can 81 engages the bracket 78 moving it rearwardly to the position also shown by dotted lines in FIG. 3. In that position, the bracket 78 engages the arm 82 to close the switch 46 and energize the circuit 43 (FIG. 2). Furthermore, during rearward movement of the cup 76 the transverse wire 77 contacts the bottom edges of all the nozzles 29 thereby automatically wiping therefrom any excess fluid colorant that may have inadvertently oozed out of the tubes 27 after the preceding dispensing cycle. Upon completion of all the dispensing cycles programmed by the sequence timer 52, the can 81 is removed from the shelf 79 and a leaf spring 83 supported by the base 71 returns the cup 76 to its forward position. During this forward movement of the cup 76 the nozzles 29 are again wiped by the wiper wire 77 to remove therefrom any externally retained colorant. Any drops of colorant removed by the wiper wire 77 fall harmlessly onto the bottom surface 84 of the cup 76. The height of the shelf 79 is adjustable so as to accommodate paint cans of different size such that any can inserted will engage the bracket 78 and produce the nozzle wiping and circuit energization operations described above.
Referring now to FIG. 5 there are shown further details of the dispensing module 11 shown in FIG. 1. The selector rod 19 extends through a lock mechanism 86 and terminates with a handle 87 that can be used to position the stop 21 at any longitudinal location within the power cylinder 13. The lock mechanism 86 includes a shell 88 supported by an annular washer 90. Defined by the inner surface of the shell 88 are spaced apart grooves 89 that are inclined toward the selector scale 19 and accommodate a retaining roller 91. The roller 91 is retained by a slot in a button 92 that is biased upwardly by a compression spring 93 so as to force the roller 91 against the selector rod 19 and thereby prevent movement thereof. Mounted on the cylinder 13 is a lever 94 that can be pressed to force the button 92 downwardly. This releases the frictional binding force applied by the roller 91 and thereby permits longitudinal movement of the selector rod 19.
As shown in FIG. 5, the dispensing piston 17 includes a central recess 95 through which the connecting rod 18 extends. Movement of the dispensing piston 17 in response to movement of the connecting rod 18 is caused by engagement of a snap ring 96 with opposite surfaces of the recess 95. Because of the lost motion provided by the recess 95 and the ring 96 initial movement of the power piston 16 is not accompanied by movement of the dispensing piston 17 until the ring 96 engages the upper surface of the recess 95. The purpose of the lost motion is to prevent pumping of unwanted colorant in response to an inadvertent elongation of the cylinder 13. Such elongation could be caused during a withdrawal cycle in any dispensing module set not to dispense as shown in FIG. 5. Hydraulic pressure against the power piston 16 would produce a force that would be transmitted through the stop 21, the rod 19 and the lock mechanism 86 as a tension on the cylinder 13. Any resultant elongation of the cylinder would move the stop 21 upwardly and permit corresponding movement of the power piston 16. Consequently, a small undesired quantity of colorant would be discharged during the subsequent dispensing cycle.
To compensate for the lost motion, the scale rod 19 is provided with an additional pair of graduations 101 (FIG. 6) that are spaced apart by a distance somewhat greater than the uniform distances separating all other graduations 102. It will be obvious that the uniform spacing between the graduations 102 represents given increments of movement by the tandemly coupled power and dispensing pistons 16 and 17. The slightly greater spacing between the initial graduations 101 compensates for the independent additional movement of the power piston 16 permitted before engagement of the snap ring 96 with the upper surface of the recess 95. Because of this lost motion the amount of dispensing piston movement provided by the more widely spaced initial graduations 101 is exactly the same as that provided by any pair of the uniformly spaced graduations 102.
Obviously, many modifications and variations of the present invention are possible in light of the above teachings. For example, the described and claimed dispenser apparatus could be used other than as described in any application in which metered quantities of fluid mediums are to be dispensed. It is to be understood, therefore, that the invention can be practiced otherwise than as specifically described. | Disclosed is a machine including a plurality of containers for a variety of paint colorants and a plurality of measuring receptacles, one connected for fluid communication with each of the containers. A cyclic pumping system simultaneously pumps metered volumes of colorant into predetermined measuring receptacles from their associated containers during a withdrawal cycle and then dispenses the metered volumes during a discharge cycle. Adjustment of selector mechanisms associated with each measuring receptacle provides the exact quantities of colorant required to formulate a specific volume of a desired paint color. A cycle timer establishes a uniform time period for each of the sequential withdrawal and dispensing cycles regardless of the colorant quantities being dispensed and a sequence timer can be preset to provide the number of sequential withdrawal and dispensing cycles required to formulate paint volumes that are a given multiple of the specific volume. | 5 |
REFERENCE TO PRIORITY DOCUMENTS
This application claims priority of co-pending U.S. Provisional Patent Application Ser. No. 60/903,486 filed Feb. 26, 2007, U.S. Provisional Patent Application Ser. No. 60/921,570 filed Apr. 3, 2007, and U.S. Provisional Patent Application Ser. No. 60/926,839 filed Apr. 30, 2007. Priority of the aforementioned filing dates is hereby claimed and the disclosures of the Provisional Patent Applications are hereby incorporated by reference in their entirety.
BACKGROUND
The present disclosure relates to devices and methods that permit fixation and stabilization of the bony elements of the skeleton. The devices permit adjustment and maintenance of the spatial relationship(s) between neighboring bones. Depending on the specifics of the embodiment design, the motion between adjacent skeletal segments may be maintained, limited or completely eliminated.
Spinal degeneration is an unavoidable consequence of aging and the disability produced by the aging spine has emerged as a major health problem in the industrialized world. Alterations in the anatomical alignment and physiologic motion that normally exists between adjacent spinal vertebrae can cause significant pain, deformity, weakness, and catastrophic neurological dysfunction.
Surgical decompression of the neural tissues and immobilization of the vertebral bones is a common option for the treatment of spinal disease. In addition to mechanical fixation, a bone graft or comparable bone-forming material is used to connect the vertebral bones and, with ossification of the graft material, the vertebral bodies are fused together by the bony bridge. Currently, mechanical fixation is most frequently accomplished by anchoring bone screws into the pedicle portion of each vertebral body and then connecting the various screw fasteners with an interconnecting rod. The screw/rod construct produces rigid fixation of the attached bones.
The growing experience with spinal fusion has shed light on the long-term consequences of vertebral immobilization. It is now accepted that fusion of a specific spinal level will increase the load on, and the rate of degeneration of, the spinal segments immediately above and below the fused level. As the number of spinal fusion operations have increased, so have the number of patients who require extension of their fusion to the adjacent, degenerating levels. The rigidity of the spinal fixation method has been shown to correlate with the rate of the degenerative progression of the adjacent segments. In specific, implantation of stiffer instrumentation, such as rod/screw implants, produced a more rapid progression of the degeneration disease at the adjacent segment than use of a less stiff fixation implant.
An additional shortcoming of the traditional rod/screw implant is the large surgical dissection required to provide adequate exposure for instrumentation placement. The size of the dissection site produces unintended damage to the muscle layers and otherwise healthy tissues that surround the diseased spine. A less invasive spinal fixation implant would advantageously minimize the damage produced by the surgical exposure of the spine.
Fixation of the spinous process segment of adjacent vertebrae provides a less rigid and less invasive method of vertebral fixation. Kapp et al. in U.S. Pat. No. 4,554,914 issued Nov. 26, 1985 disclosed a device of two elongated plates that are adapted to clamp onto adjacent spinous process. The plates are disadvantageously connected by locking bolts that transverse the substances of each spinous process. Bolts placed in this configuration will necessarily weaken the bony elements and lead to spinous process fractures and construct failure. Howland et al in U.S. Pat. No. 5,496,318, issued Mar. 5, 1996 disclosed the placement of an inter-spinous process spacer and encircling tension band to reduce vertebral motion. While the device can reduce vertebral flexion and extension, it can not effectively resist vertebral movement in the other motion planes. In U.S. Pat. No. 6,312,431 issued Nov. 6, 2001, Asfora disclosed a device comprised of two opposing plates that are interconnected by a malleable tether and adapted to capture the adjacent spinous processes between them. As with the Howland device, the fixation strength of this implant is limited by the mobile interconnecting tether. As such, neither implant can effectively immobilize the vertebral bones in all relevant motion planes. The lack of fixation significantly increases the possibility that the bone graft will not heal, the vertebral bones will not fuse, the construct will fail and the patient will develop chronic pain.
Superior immobilization devices were disclosed by Robinson et al. in U.S. Pat. No. 7,048,736 issued May 23, 2006 and by Chin et al. in U.S. Pub. Nos. 2007/0179500, 2007/0233082 and 2007/0270840. Each of these documents disclosed plates (or segments thereof) that engage each side of two adjacent spinous processes, wherein the plates are interconnected by a rigid member that resides within the interspinous space. Mechanical testing of the Robinson device was recently published by J C Wang et al. in the Journal of Neurosurgery Spine (February 2006; 4(2):160-4) and the text is hereby incorporated by reference in its entirety. The device was found to be weaker than conventional fixation techniques in all modes of vertebral movement and particularly lacking in fixation of rotational motion. Because of its limited stabilization properties, the device should be used in conjunction with additional implants. (See Wang J C et al. in the Journal of Neurosurgery Spine. February 2006; 4(2):132-6. The text is hereby incorporated by reference in its entirety.)
As an additional shortcoming, the Robinson device can not be used to fixate the L5 vertebral bone to the sacrum. The spinous process of the first sacral vertebra is simply too small to permit adequate bone purchase and fixation with either the Robinson or Chin device. Since the L5/S1 level is a frequent site of spinal disease, the inapplicability of these devices at this level is a significant limitation of these implants.
In U.S. Pub. Nos. 2006/0036246, Carl and Sachs disclose a fixation device adapted to fixate the spinous process of one vertebral level to bone screws anchored into the pedicle portion of an adjacent vertebral level. While this invention would permit application at the L5/S1 level and circumvent one disadvantage of the aforementioned spinous process fixation plates, it relies on direct screw fixation into the distal aspect of the spinous process. This technique disadvantageously replicates the inadequate fixation characteristics of the Kapp device previously discussed (U.S. Pat. No. 4,554,914) and carries a high likelihood of spinous process fracture and complete construct failure. Indeed, the inventors try to address this design flaw by augmenting the strength of the spinous process through the use of an internal bone filler or an external brace. Regardless of these efforts, however, the disclosed device provides a cumbersome implant that carries a high likelihood of spinous process fracture and complete loss of vertebral fixation.
SUMMARY
The preceding discussion illustrates a continued need in the art for the development of a spinous process device and method that would provide superior vertebral fixation than existing spinous process implants. The device should be amenable to placement through a minimally invasive surgical approach. When vertebral fusion is desired, the device desirably provides adequate fixation in all movement planes so that the probability of bone graft healing is maximized. The implant would desirably provide less rigid fixation than traditional rod/screw fixation.
In the treatment of spinal disease, it is sometimes desirable to limit vertebral motion in one or more axis while maintaining movement in other motion planes. Vertebral segments that are treated using these motion preservation techniques will not be fused and a bone graft spanning the space between the vertebral bones is not employed. When motion preservation is desired, the device provides adequate fixation onto each attached vertebral bone while controlling the motion between them. Moreover, a hybrid device would advantageously provide fusion at one or more vertebral levels and motion preservation at other vertebral levels.
This application discloses novel implants and methods of implantation that address current deficiencies in the art. In an embodiment, there is disclosed an orthopedic device adapted to fixate the spinous processes of one vertebral bone to bone fasteners anchored into the pedicle portion of an adjacent vertebral body. The implant may capture the spinous process by using an encircling contoured rod or hooks. Alternatively, the implant may contain at least one barbed bone engagement member located on each side of the spinous process and adapted to forcibly abut and fixate into the side of the spinous process. The device further contains a locking mechanism that is adapted to transition from a first unlocked state wherein the device components are freely movable relative to one another to a second locked state wherein the device is rigidly immobilized and affixed to the bone.
Alternative embodiments of the aforementioned device are disclosed. In one embodiment, the device is adapted to fixate at least three vertebral bones. In that embodiment, the device captures the spinous processes of one vertebral bone and fixates it onto an elongated rod that is adapted to engage bone fasteners anchored into the pedicle portion of at least two additional vertebral bodies. In another embodiment, the device is adapted to attach onto the rod portion of an existing screw/rod construct and functions to extend the level of vertebral fixation.
In other embodiments, there is disclosed a series of orthopedic devices that are adapted to fixate onto the spinous processes of one vertebral bone and onto bone fasteners anchored into the pedicle portion of an adjacent vertebral body. The device provides controlled movement between the two attached vertebral bones. Multiple iterations of this device are illustrated. In some embodiments, bone graft or bone graft substitute may be used to fixate and fuse the device onto each of the anchored vertebral bones while still permitting movement between them.
In an alternative embodiment, the device also contains an elongated rod that is adapted to engage bone fasteners anchored into the pedicle portion of at least two additional vertebral bodies. This design feature produces a hybrid device that provides controlled motion between at least a first pair of vertebral bones and rigid immobilization between at least a second pair of vertebral bones.
In an additional embodiment, a implant is used to fixate onto the spinous process of each of two adjacent vertebral bone. The implant contains at least one barbed bone engagement member located on each side of the spinous process and adapted to forcibly abut and fixate into the side of the spinous process at each level. The implant allows controlled movement between the two attached spinous processes. The implant may further contain a cavity adapted to accept a bone graft or bone graft substitute so that, with bone formation, the device members may fuse onto the spinous processes and provide superior device adhesion to the vertebral bone. In another embodiment, a bone containment device is disclosed that is adapted to span the distance between the lamina of neighboring vertebrae. The device contains an internal cavity adapted to accept a bone graft or a bone graft substitute so that, with bone formation, the lamina of neighboring vertebral bones are fused together.
In one aspect, there is disclosed an orthopedic device adapted to fixate at least two vertebral bones, comprising: at least one bone engagement member located on each side of a spinous process of a first vertebra wherein the bone engagement member are each forcibly compressed and affixed onto the sides of the spinous process; a connector member adapted to interconnect each bone engagement members on one side of a spinous processes of a first vertebra with at least one bone fastener affixed to a second vertebra; a cross member extending across the vertebral midline and adapted to adjustably couple the bone engagement member and connector member on one side of the vertebral midline with the bone engagement member and the connector member on the other side of the vertebral midline; and a connection between the bone engagement members the connection comprising a connector member, and a cross member wherein the connection is capable of reversibly transitioning between a first state where the orientation between the bone engagement member, the connector member and the cross member is changeable in at least one plane and a second state where the orientation between the bone engagement member, the connector member and the cross member is rigidly affixed.
In another aspect, there is disclosed an orthopedic device adapted to fixate at least two vertebral bones, comprising: at least one bone engagement member located on each side of a spinous process of a first vertebra wherein the bone engagement member is forcibly compressed and affixed onto the sides of the spinous process; a connector member adapted to inter-connect each bone engagement members on one side of a spinous processes of a first vertebra with at least one rod that is used to inter-connect at least two bone fastener affixed to additional vertebral bones; a cross member extending across the vertebral midline and adapted to adjustably couple the bone engagement member and connector member on one side of the vertebral midline with the bone engagement member and connector member on the other side of the vertebral midline; and a connection between a bone engagement members, the connection comprising a connector member and a cross member wherein the connection is capable of reversibly transitioning between a first state where the orientation between the engagement member, the connector member and the cross member is changeable in at least one plane and a second state where the orientation between the engagement member, the connector member and the cross member is rigidly affixed.
In another aspect, there is disclosed an orthopedic device adapted to fixate at least two vertebral bones, comprising: at least one contoured rod that contacts at least one surface of the spinous process of a first vertebra; a connector member adapted to interconnect one end of the contoured rod that is located on one side of a spinous processes of a first vertebra with a bone fastener affixed to a second vertebra; and a device body member extending across the vertebral midline and adapted to adjustably couple at least one end of the contoured rod with the connector members wherein the device body member further contains at least one locking mechanism that is capable of reversibly transitioning between a first state wherein the orientation between the contoured rod and at least one connector member is changeable in at least one plane and a second state wherein the orientation between the contoured rod and at least one connector member is rigidly affixed.
In another aspect, there is disclosed an orthopedic device adapted to fixate at least two vertebral bones, comprising: at least one hook member that contacts at least one surface of the posterior aspect of a first vertebra; and a connector member adapted to interconnect one end of the hook member attached to the posterior aspect of a first vertebra with a bone fastener affixed to a second vertebra; a device body member extending across the vertebral midline and adapted to adjustably couple at least one hook member attached to the posterior aspect of a first vertebra the connector members wherein the device body member further contains at least one locking mechanism that is capable of reversibly transitioning between a first state wherein the orientation between the hook member and at least one connector member is changeable in at least one plane and a second state wherein the orientation between the hook member and at least one connector member is rigidly affixed.
In another aspect, there is disclosed an orthopedic device adapted to control motion between at least two vertebral bones, comprising: at least one bone engagement member located on each side of a spinous process of a first vertebra wherein the bone engagement member is forcibly compressed and affixed onto the sides of the spinous process; a connector member adapted to interconnect each bone engagement members on one side of a spinous processes of a first vertebra with at least one bone fastener affixed to a second vertebra, wherein the engagement member contains a channel adapted to accept an end of the connector member and wherein the motion permitted by the interaction of each of the two channel and connector member surfaces determines the motion profile permitted by the device; a cross member extending across the vertebral midline and adapted to adjustably couple bone engagement member and connector member on one side of the vertebral midline with the bone engagement member and connector member on the other side of the vertebral midline; and a connection between the bone engagement members and cross member wherein the connection is capable of reversibly transitioning between a first state where the orientation between the engagement member and the cross member is changeable in at least one plane and a second state where the orientation between the engagement members and the cross member is rigidly affixed.
Other features and advantages will be apparent from the following description of various embodiments, which illustrate, by way of example, the principles of the disclosed devices and methods.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows perspective views of an orthopedic implant adapted to fixate the spinous process of a first vertebral bone to screw fasteners affixed to the pedicle portion of a second vertebral bone.
FIG. 2 illustrates multiple views of the implant.
FIG. 3 shows an exploded view of the implant.
FIG. 4 shows a section view through the locking mechanism of the implant.
FIG. 5 shows a perspective view of the implant attached onto a segment of the spine.
FIGS. 6 and 7 illustrate multiple views of a second device embodiment.
FIG. 8 shows a partly exploded view of the second device embodiment.
FIGS. 9 and 10 illustrate multiple views of another device embodiment.
FIG. 11 illustrates a perspective view of a preferred embodiment of the current invention.
FIG. 12 shows the device of FIG. 11 in multiple orthogonal planes.
FIG. 13 shows an exploded view of the implant.
FIGS. 14 and 15 illustrate cross-sectional views of the locking mechanism of the implant.
FIGS. 16 through 18 illustrate devices and methods for vertebral distraction in preparation for device placement.
FIG. 19 shows a method of vertebral and nerve decompression.
FIGS. 20 a - 20 c show the device of FIG. 11 attached to the spine.
FIG. 21 illustrates the addition of a second device at an adjacent spinal level.
FIG. 22 shows an additional device embodiment that is adapted to fixate multiple vertebral levels.
FIG. 23 shows a perspective view of an alternative embodiment of the device shown in FIG. 11 .
FIG. 24 shows the device of FIG. 23 in multiple orthogonal planes.
FIG. 25A shows the device of FIG. 23 attached to a spine model.
FIG. 25B illustrates a cross-sectional view wherein the spinous process fixation screw is shown.
FIG. 26A shows another embodiment of the device of FIG. 11 wherein the rods are replaced with paddle attachment members.
FIG. 26B shows an exemplary embodiment of a paddle attachment member.
FIGS. 27 and 28 illustrate additional device embodiments.
FIG. 29 shows another device embodiment used to fixate three or more vertebral bones.
FIG. 30 shows the device of FIG. 29 attached to the spine.
FIGS. 31 to 33 illustrate a device adapted to attach onto existing rod/screw instrumentation.
FIG. 34 shows a perspective view of a device embodiment adapted to preserve motion between the vertebral bodies.
FIG. 35 shows the device of FIG. 34 in multiple orthogonal planes.
FIG. 36 illustrates an exploded view.
FIG. 37A shows a cross-sectional view through the articulation mechanism.
FIG. 37B shows a cross-sectional view through the locking mechanism.
FIG. 38 illustrates a perspective view of an additional device embodiment.
FIG. 39 shows the device of FIG. 38 in multiple orthogonal planes.
FIG. 40 illustrates an exploded view.
FIGS. 41 , 42 and 43 illustrate cross-sectional views at different points within the device.
FIG. 44 shows a perspective view of an alternate embodiment of the motion preservation device.
FIG. 45 illustrates a perspective view of an additional device embodiment.
FIG. 46 shows the device of FIG. 45 in multiple orthogonal planes.
FIG. 47 illustrates an exploded view.
FIG. 48 shows a cross-sectional view through the locking mechanism.
FIG. 49 illustrates a perspective view of an alternative embodiment.
FIG. 50 shows an exploded view of the device of FIG. 49 .
FIG. 51 shows an alternative embodiment of the device in FIG. 49 .
FIGS. 52 and 53 illustrate additional device embodiments.
FIG. 54 illustrates another device embodiment.
FIG. 55 shows the device of FIG. 54 in multiple orthogonal planes.
FIG. 56 shows an exploded view.
FIG. 57 illustrates an additional device embodiment.
FIG. 58 shows exploded views of the device.
FIG. 59 shows a sectional view through the locking mechanism and articulation surface.
FIG. 60A shows the posterior aspect of a spine.
FIG. 60B shows a bone containment implant in place at the L4/5 level.
FIG. 61A shows a perspective view of a bone containment implant
FIG. 61B illustrates the device of FIG. 61A in multiple orthogonal views.
FIG. 62 shows another embodiment of the bone containment implant in place at the L4/5 level.
DETAILED DESCRIPTION
FIGS. 1-3 show various views of an orthopedic device adapted to fixate the spinous process of a first vertebral bone to screw fasteners affixed to the pedicle portion of a second vertebral bone. The device includes a central member 110 having a pair of movably attached rods 115 extending outwardly therefrom. A central threaded bore 112 is contained in member 110 and serves as an attachment point for the device placement instruments. Each of the rods 115 has a ball-shaped head that is positioned inside a complimentary shaped seat inside the central member 110 . The spherical head is positioned into the seat inside member 110 and retained in place by collapsible “C” ring 116 . In the unlocked state, the spherical head of rod 115 is freely movable within the seat of member 110 .
A U-shaped rod 120 is also attached to the central member 110 . The rod 120 can be fixated to the central member 110 by tightening a pair of lock nuts 125 downwardly onto ends of the rod 120 . As shown in FIG. 2 , the lock nuts 125 are positioned atop the heads of the rods 115 . This permits the lock nuts 125 to provide a downward force onto both the U-shaped rod 120 and the heads of the rods 115 . In this manner, the lock nuts 125 serve as a locking member that simultaneously locks the U-shaped rod 120 and the rods 115 to the central member 110 . The U-shaped rod 120 is adapted to fit around a spinous process of a vertebral bone. The rod 120 can have various shapes and configurations beside a U-shape that permits the rod to be fit around a spinous process.
FIG. 3 shows an exploded view of the device and FIG. 4 shows a cross-sectional view of the device through the locking mechanism. A locking plug 305 is interposed between each of rods 120 and the spherical heads of rods 115 . As the locking nuts 125 are tightened downward onto the rod 120 , the locking plugs 305 are advanced onto the spherical heads of rods 115 , locking and immobilizing the rods 115 relative to the central member 110 .
FIG. 5 shows a perspective view of the device attached onto a segment of the spine. The vertebrae are represented schematically and those skilled in the art will appreciate that actual vertebral bones may include anatomical details that differ from those shown in FIG. 5 . The U-shaped rod 120 is shaped such that it can wrap around or otherwise secure onto the spinous process of a vertebral body. The central member 110 is also positioned to contact the spinous process. The foot plate 118 of member 110 is preferably positioned beneath the lamina of the upper vertebral bone. The U-shaped rod 120 can be adjusted relative to the central member 110 prior to the actuation of the lock nuts. The rod 120 can adjustably slide relative to the central member 110 to accommodate spinous processes of various sizes. Preferably, the rod 120 is positioned around the spinous process in a manner that tightly captures the top surface of the spinous process against the central rod bend and the bottom surface of the spinous process or lamina against member 110 . After appropriate positioning of rod 120 , the free end of each rod 115 is rotated and placed into the rod-receiving seat of the previously placed bone fasteners 122 . The fastener lock nuts are tightened and the ends of rods 115 are immobilized relative to the fasteners. Subsequently, tightening of lock nuts 125 immobilizes rod 122 , rods 115 and central member 110 relative to one another and produce a rigid implant. As illustrated, the device fixates the spinous processes of a first vertebral bone to bone fasteners anchored into the pedicle portion of a second vertebral bone.
FIGS. 6 and 7 show another device embodiment. An exploded view is shown in FIG. 8 . While similar to the previous embodiment, the current device uses rods 120 with terminal hooks 805 to attach onto the upper aspect of the spinous process or upper edge of the lamina of the upper vertebral bone. As shown in the exploded view of FIG. 8 , the end 805 of each rod 120 is configured as a hook wherein the two hooks 805 a and 805 b can interfit with one another. The cylindrical end of each rod 120 is adapted to fit within complimentary bores 126 of member 110 .
As in the previous embodiment, central member 110 has a cavity adapted to accept the spherical head of each rod member 115 . “C” ring 116 retains the spherical heads attached to member 110 after device assembly. The locking mechanism of the device is similar to that of the previous embodiment. Advancement of lock nuts 125 immobilizes rods 120 , rods 115 and central member 110 relative to one another. The placement protocol is similar to that of the previous embodiment. However, as noted, hook member 805 may be alternatively attached onto the superior edge of the lamina of the upper vertebral bone.
FIGS. 9 and 10 illustrate multiple views of another device embodiment that fixates the spinous processes of one vertebral bone to bone fasteners anchored into the pedicle portion of an adjacent vertebral body. The vertebrae are represented schematically and those skilled in the art will appreciate that actual vertebral bones may include anatomical details that differ from those shown in these figures. In this embodiment, a U-shaped rod 120 is sized and shaped to wrap around the spinous process of a first vertebral body. Opposed ends of the rod 120 are coupled to bone fasteners such as bone screw assemblies 810 . The bone fasteners are attached to the pedicles of an adjacent vertebral body. Unlike the previous embodiments, this device does not include a central member.
FIGS. 11-13 show another embodiment of a device that fixates the spinous processes of one vertebral body to bone fasteners anchored into the pedicle portion of an adjacent vertebral body. The device includes a pair of central members 1105 a and 1105 b (collectively central members 1105 ) with opposed interior surfaces. Fixation members such as barbs 1107 are positioned on the interior surfaces such that the barbs face inward for attaching to a spinous process positioned between the central members 1105 . The central members 1105 are slidably mounted on a rod 1110 such that the central members 1105 can move toward and away from one another. In this manner, the size of the space between the central members 1105 can be adjusted to accommodate spinous processes of various sizes. Further, the orientation of members 1105 relative rod 1110 is adjustable in multiple planes.
Each rod 115 is coupled to a central member 1105 such that it extends outwardly therefrom. Rod 115 has a spherical head that is positioned inside a complimentary shaped seat inside a respective central member 1105 and retained in position collapsible “C” ring 116 . In the unlocked state, the spherical head of rod 115 is freely movable within member 1105 in a ball and socket manner. The end of each rod 115 can be attached to a bone fastener, such as pedicle screw assemblies 810 , that is anchored to the pedicle portion of a vertebral bone.
The top surface of each member 1105 contains a bore 1127 , which extends from the top surface to the cavity adapted to receive the spherical head of rod 115 . The upper aspect of bore 1127 is threaded. Bore 1127 is crossed by bore 1129 , wherein the latter bore extends from the lateral to the medial wall of member 1105 . A cross sectional view through the locking mechanism is shown in FIGS. 14 and 15 . Spherical member 1410 has central bore 1412 and full thickness side cut 1414 , thereby forming a compressible “C” ring that can be compressed onto the contents of bore 1412 . In the assembled device, rod 1110 is positioned within central bore 1412 and can translate relative to it. With the application of a compressive load onto the outer surface of member 1410 by threaded locking nut 1125 , member 1410 is compressed onto rod 1110 and the latter is immobilized within bore 1412 . Retention pins 1145 are used to retain rod 1110 within member 1410 in the assembled device.
Advancement of each of lock nuts 1125 immobilizes rod 1110 , rod 115 and central member 1105 relative to one another and renders the device rigid. With reference to the cross-sectional views of FIGS. 14 and 15 , tightening lock nut 1125 downwardly onto spherical member 1410 produces a compressive load onto rod 1110 and a downward force onto locking plug 1405 . The latter is pushed towards the spherical head of rod 115 , thereby immobilizing rod 115 within central members 1105 . In this manner, advancement of each lock nut 125 provides a downward force onto both rod 1110 and the spherical head of rod 115 contained with each member 1105 . Thus, each lock nut 125 serves as a locking member that simultaneously locks rod 1110 and rod 115 to the central member 1105 .
The spinal level to be implanted has an upper and a lower vertebral bone and the device is attached onto the posterior aspect of these vertebral bones. Prior to device placement, the upper and lower vertebral bones are distracted to facilitate decompression of the nerve elements. FIG. 16 shows a perspective, assembled view of a distractor device. For clarity of illustration, the vertebral bodies are represented schematically and those skilled in the art will appreciate that actual vertebral bodies include anatomical details not shown in FIG. 16 . The device generally includes a pair of anchors that include elongate distraction screws 1610 coupled to a platform 1615 . Each of the distraction screws 1610 is advanced into the posterior surface of a spinous process and follows a posterior to anterior trajectory along the long axis of the spinous process. The distal end of each screw includes a structure for attaching to the spinous process, such as a threaded shank. The proximal ends of the distraction screws 1610 are attached to the platform 1615 . The screws 1610 are axially positioned within sheaths 1619 that surround the screws and extend downwardly from the platform 1615 .
The distraction actuator 1622 is actuated to cause one of the distraction screws to slide along the rail 1621 such that it moves away form the other distraction screw. This applies a distraction force to the vertebral bodies to distract the vertebral bodies—as shown in FIG. 17 . (In another embodiment, shown in FIG. 18 , the distraction screws are replaced by clip members 1805 that couple to the spinous processes or lamina of the vertebral bodies. Other known methods of vertebral distraction may be alternatively used.) The decompression of the nerve elements is performed under distraction and it is schematically illustrated in FIG. 19 . The bony and ligament structures that are compressing the nerves are removed from the lower aspect of the lamina of the upper vertebra and the upper aspect of the lamina of the lower vertebra (regions 1152 ).
Prior to device implantation, bone fasteners 810 had been placed into the pedicel portion of the lower vertebra on each side of the midline. A bone graft or bone graft substitute is packed with the facet joints and used to span the distance between the lamina of each of the upper and lower vertebra. The implant is positioned at the level of implantation such that opposing central members 1105 are disposed on either side of a spinous process of a the upper vertebral body. A compression device (not shown) attaches onto the lateral wall of each opposing central member 1105 at indentation 11055 . The compression device forcefully abuts the medial aspect of each central member 1105 against a lateral wall of the spinous process and drives spikes 1107 into the bone. Spikes 1107 provide points of device fixation onto the each side of the spinous processes.
With the compression device still providing a compressive force, the distal ends of rods 115 are positioned into the rod receiving portions of bone fasteners 810 . The locking nuts of the fasteners are actuated so that each rod 115 is locked within the respective fastener. Lock nuts 1125 are actuated, locking the device's locking mechanism and immobilize opposing central members 1105 , the interconnecting rod 1110 and rods 115 relative to one another. The compression device is removed, leaving the device rigidly attached to the upper and lower vertebral bones.
FIGS. 20 a - 20 c show the device of FIG. 11 attached to the spine. As mentioned, the central members 1105 are spaced apart with a spinous process of an upper vertebra positioned in the space between them. The rods 115 are oriented so that they extend toward respective bone fasteners that are anchored to the pedicle portion of a lower vertebra. In this manner, the device fixates the spinous processes of one vertebral body to bone fasteners anchored into the pedicle portion of an adjacent vertebral body. FIG. 21 illustrates the addition of a second device at an adjacent spinal level. Note that device can be used to fixate the L5 vertebra to the sacrum.
FIG. 22 shows another embodiment of a device that is similar to the device of FIG. 11 . In this embodiment, the rods 115 have a length that is sufficient to span across multiple vertebral levels. This permits the device to be used to fixate multiple vertebral bodies across multiple levels to a spinous process of a single vertebral body.
FIGS. 23 and 24 show an alternative embodiment. In this device, at least one of the central members 1105 has a portion 2305 that extends outwardly and overhangs the space between the central members 1105 . The portion 2305 is sized, shaped, and contoured such that it can fit around the spinous process that is positioned between the central members 1105 . A bore 2310 extends through the portion 2305 . The bore receives a bone fastener, such as a bone screw, that can be driven into the posterior surface of the spinous process and having a posterior to anterior trajectory that substantially follows the long axis of the spinous process. FIG. 25A shows the device of FIG. 23 attached to a spine model. FIG. 25B illustrates a cross-sectional view wherein the spinous process fixation screw 2510 is shown extending through the portion 2305 and into the spinous process.
FIG. 26A shows another embodiment of the device of FIG. 11 wherein rods 115 are replaced with paddle attachment members 2605 . FIG. 26B shows an exemplary embodiment of a paddle attachment member 2605 . The paddle attachment member 2605 is used in place of a rod 115 . The attachment member 2605 has a head that fits into the central member 1105 and also has an opening 2610 that can be coupled to a bone fastener, such as a pedicle screw assembly.
FIGS. 27 and 28 show additional embodiments of the device of FIG. 11 . In these devices, a portion 2705 is sized and shaped to capture the inferior surface of the lamina of the upper vertebral bone. In the embodiment of FIG. 27 , the portion 2705 extends outward from the rod 1110 . In the embodiment of FIG. 28 , the portion 2705 extends outward from each of the central members 1105 .
FIG. 29 shows another device embodiment used to fixate three or more vertebral bones. In this embodiment, the central members 1105 are sufficiently long such that the spinous processes of one or more vertebral bodies can fit between the central members 1105 . The central members 1105 have barbs or other attachment means that are adapted to secure to the spinous processes. One end of each of the central members has a rod 115 movably attached thereto while the opposed end has another rod 117 movably attached thereto. The rods 115 and 117 can extend outward at any of a variety of orientations and angles relative to the central members. The rods 115 and 117 can be attached to pedicle screw assemblies for attaching the device to adjacent vertebral bodies. Thus, the device is adapted to fixate the spinous process of a middle vertebra to screw fasteners attached to the pedicle portions of an upper and a lower vertebra. FIG. 30 shows the device of FIG. 29 attached to a schematic representation of the spine.
FIGS. 31 to 33 illustrate a device adapted to attach onto existing rod/screw instrumentation and extend the fusion to a additional level. Each of two rods 3110 is attached to a pair of vertebral bodies in a conventional screw/rod fixation arrangement. Each rod 3110 is attached to two pedicle screw assemblies 3115 —as shown in FIG. 31 . The extension device has a pair of central members 1105 that are positioned on opposed sides of a spinous process of an upper vertebra. Rods 115 extend outwardly from the device. The rods 115 movably attach to the rods 3110 via a pair of brackets 3120 . Perspective views of bracket 3120 are shown in FIG. 33 . Each bracket is sized to receive a spherical end of rod 115 while also receiving a cylindrical segment of rod 3110 . Actuation of the locking screw 3130 of bracket leads to the upward movement of member 3150 and the immobilization of rod 3110 and the special head of rod 115 within bracket 3120 . A cross-sectional view of the locking mechanism is shown in FIG. 32 .
FIG. 34 illustrates a device embodiment 605 adapted to fixate onto the spinous processes of one vertebral bone and bone fasteners anchored into the pedicle portion of an adjacent vertebral body. The device provides controlled movement between the two attached vertebral bones. FIG. 35 shows the device in multiple orthogonal planes and FIG. 36 shows the device components in an exploded view. Each of opposing body members 612 has a top surface, bottom surface, an outer side surface, an inner side surface and a front and back surface. Each medial surface contains spike protrusions 617 that are adapted to be driven into the side surface of a spinous process and serve to increase device fixation onto bone. The lateral surface contains opening 622 of channel 624 that is intended to receive the spherical head 632 of rod 634 . Movement of head 632 within channel 624 forms the mobile bearing surface of the implant. A cross-sectional view of head 632 contained within channel 624 is illustrated in FIG. 37A . As shown, head 632 can move unopposed within channel 624 . In an alternative embodiment, a spring member is placed within channel 624 so that the position of head 632 is biased against movement away from a default position. Preferably, in the default position, head 632 is positioned at the end of channel 624 that is adjacent to bore 628 —as shown in FIG. 34 .
The top surface of each body member 612 contains bore 628 adapted to accept a bone fastener 629 . Preferably, but not necessarily, bores 628 of the opposing body members 612 are angled in one or more planes so that the seated bone fasteners are not parallel. Non-parallel bore trajectories provide a crossed screw configuration and increased resistance to screw pull-out. As previously discussed, the seated screws may engage any portion of the lamina or spinous process bone but are preferably targeted and placed to engage the junction of the lamina and spinous process.
The top surface of each body member 612 contains a cavity 636 with full thickness bore holes 638 within the medial cavity wall. The cavity is adapted to accept a segment of bone graft or bone graft substitute and to function as a bone containment cage. With time, the graft material within cavity 636 of an implanted device 605 will fuse with the lateral wall of the spinous process and provide an additional attachment point with the underlying bone. Since it contains living bone tissue, ossification of the fusion mass will provide a stronger and more enduring bridge between the implant and vertebral bone than any mechanical fastener.
The top surface of each body member 612 contains a second bore 642 , wherein partial thickness bore 642 does not extend through to the bottom surface of the body member. The upper aspect of bore 642 is threaded. Bore 642 is crossed by bore 646 , wherein the full thickness bore 646 extends from the lateral to the medial wall of body member 612 . Bores 642 and 646 contain the device's locking mechanism. (A cross sectional view through the locking mechanism is shown in FIG. 37B .) Spherical member 652 has central bore 654 and full thickness side cut 655 , thereby forming a compressible “C” ring that can be compressed onto the contents of bore 654 . In the assembled device, longitudinal member 658 is positioned within central bore 654 and can translate relative to it. With the application of a compressive load onto the outer surface of member 652 by threaded locking nut 656 , spherical member 652 is compressed onto longitudinal member 658 and the latter is immobilized within bore 654 . Retention pins 645 are used to retain longitudinal member 658 in the assembled device. In the assembled configuration, retention pins 647 are positioned within side cut 655 of spherical member 652 so as to limit the extent of rotation of opposing body members 612 .
The spinal level to be implanted has an upper and a lower vertebral bone and the device is attached onto the posterior aspect of the vertebral bones. Prior to device placement, bone fasteners 660 had been placed into the pedicel portion of the lower vertebra on each side of the midline. In addition, each side of the spinous process of the upper vertebra is gently decorticated in order to maximize the likelihood of bone (fusion) mass formation. Each of opposing body members 612 is placed on an opposite side of the spinous process of the upper vertebra. A compression device (not shown) is used to compress each body member 612 onto a side of the spinous process and drive the spike protrusions 617 into the bone surface. With the compression device still providing a compressive force, the distal ends of rods 634 are positioned into the rod receiving portions of bone fasteners 660 . Preferably, each head 632 is positioned at the end of channel 624 immediately adjacent to bore 628 prior to locking bone fasteners 660 onto rods 634 . This configuration assures that vertebral extension is limited to the position set at the time of surgery. The locking nuts of the fasteners are then actuated so that each rod 634 is locked within the respective fastener 660 . Locking nuts 656 of device 605 are then actuated, locking the device's locking mechanism and immobilize opposing body member 612 and the interconnecting longitudinal member 658 relative to one another. The compression device is removed, leaving the device rigidly attached to the upper and lower vertebral bones. Preferably, but not necessarily, cavity 636 is packed with bone graft or bone graft substitute so that, with time, a bone fusion mass connects the device to the side wall of the spinous process. If desired, a bone fastener 629 can be placed through each bore hole 628 into the underlying bone and further increase device fixation onto bone.
It is important to note that spike protrusions 617 and fastener 629 provide immediate device fixation to the upper vertebral level. With time, these fixation points may weaken from the cyclical device loading that invariably results during routine patient movement. Formation and ossification of the bone fusion mass contained within cavity 636 provides long-term fixation for the device. In contrast to spike and screw fixation, the fusion mass will increase in strength with time and provide a more permanent attachment point for the device. In this way, the immediate fixation of the spike and fasteners and the long-term fixation of the fusion mass compliment one another and provide optimal fixation for the device.
After device implantation, certain movements between the upper and the lower vertebras are permitted while other movements are limited. For example, the illustrated embodiment permits forward flexion of the upper vertebra relative to the lower vertebra. However, extension is limited by the position set at the time of implantation (that is, the position of head 632 within channel 624 ). Anterior translation of the upper vertebral bone relative to the lower vertebral bone is significantly limited so that aberrant motion resulting in spondylolisthsis is prevented. Lateral flexion between the vertebral bones is permitted but to a lesser degree than that of normal physiological vertebral motion. Vertebral rotation is substantially eliminated.
These limitations are determined by the interaction of heads 632 with channels 624 and can be varied by the shape and/or orientation of one or both of these structures. For example, extending the diameter of channel 624 in a medial to lateral direction will permit an increase in vertebral rotation. Further, a channel with lesser medial to lateral diameter at one end and a greater medial to lateral diameter at another end will permit a variable degree of rotational movement, wherein the extent of rotation depends of the extend of anterior flexion. This configuration can simulate physiological vertebral motion, wherein grater vertebral rotation is permitted in anterior flexion than in extension. As can be easily seen, numerous alternative motion characteristics can be produced by one of ordinary skill in the art through the simple manipulation of the shape and/or orientation of heads 632 and/or channels 624 . In addition, malleable members can be placed within channel 624 so that the position of head 632 is biased towards a default position and movement away from that position is opposed.
An alternative embodiment is shown in FIG. 38 . While similar to the preceding embodiment, this device provides a cross-member that inter-connects the bone fasteners 660 so as to obviate the possibility of fastener rotation (along its long axis) within the pedicle portion of the bone. The cross member also increases the resistance to fastener pull-out from the lower vertebral bone. FIG. 39 shows the device in multiple orthogonal planes. An exploded view is shown in FIG. 40 and multiple cross-sectional views are shown in FIGS. 41 , 42 and 43 .
Device 685 is adapted to fixate onto the spinous processes of one vertebral bone and bone fasteners anchored into the pedicle portion of an adjacent vertebral body. As before, each of opposing body members 612 has side spikes 617 , a central cavity 636 adapted to accept a bone forming graft, and a locking mechanism adapted to immobilize body members 612 to interconnecting longitudinal member 658 . (A section view through the locking mechanism is shown in FIG. 41 .) The top surface of each body member 612 contains bore 628 adapted to accept a bone fastener 629 . Side indentations 662 receive the compression device during device implantation.
The inferior surface of each body 612 contains opening 682 of channel 686 . Head 692 of rod 690 travels within channel 686 and forms the mobile bearing surface of the implant. Retention pin 681 ( FIG. 40 ) is used to retain head 692 within channel 682 and prevent device disassembly. As before the motion characteristics permitted by the implant are determined by the interaction of heads 692 with channels 686 and can be varied by the shape and/or orientation of one or both of these structures. (A section view through the bearing surface is shown in FIG. 42 .) Examples of the possible configuration changes were previously discussed. In addition, malleable members can be placed within channel 682 so that the position of head 692 is biased towards a default position and movement away from that position is opposed.
Interconnecting rod 702 is used to attach the device onto the bone fasteners imbedded within the pedicel portion of the lower vertebral body. Rod 702 is comprised of telescoping segments 704 and 706 so that the rod length may be varied. Segment 704 contains rectangular protrusion 704 that, in the assembled state, is housed with a complimentary bore within segment 706 . A cross-sectional view through rod 702 is shown in FIG. 43 . A side rod 690 with head 692 (bearing surface) is contained in each of segments 704 and 706 —as illustrated. The procedure for placement of device 685 is similar to the placement procedure previously described for device 605 .
An alternative device embodiment is illustrated in FIG. 44 . While the portion of the device that attaches onto the spinous process of the upper vertebral bone is largely identical to that of device 605 , the current embodiment contains two contoured rods 712 that are adapted to attach bone fasteners at multiple vertebral levels. In use, bodies 612 attach onto the spinous process segment of an upper vertebral while contoured rod 712 attaches onto bone fasteners that are attached onto a middle and a lower vertebral level. As before, the bone fasteners are preferably, but not necessarily, anchored into the pedicle portion of the middle and lower vertebral bones. In this way, the current embodiment provides a hybrid device that permits vertebral movement between a first and second vertebral bones and complete immobilization (and fusion) between a second and third vertebral bone. Clearly, additional fasteners can be attached to contoured rod 712 to immobilize additional vertebral levels. This device is particularly adapted for use within the lower lumber spine where it is frequently desirable to immobilize and fuse the S1 and L5 vertebral levels and preserve motion between the L5 and L4 vertebral levels.
FIG. 45-48 show another embodiment of a device. The device includes central members 4510 that are slidably attached to a rod 4515 that extends through a bore 4513 in both of the central members 4510 . Each of the central members 4510 has a u-shaped slot 4517 that is sized to receive a contoured rod 115 . As in the previous embodiments, the central members are positioned on opposed sides of a spinous process and engaged thereto via spikes or barbs on the interior surface of the central members.
A pair of locking nuts 125 are positioned within boreholes of central members 4510 and adapted to produce a compressive force onto “C” ring 119 and interconnecting rod 4515 . A cross-sectional view of the locking mechanism is illustrated in FIG. 48 . As illustrated in prior embodiments, each ember 4510 can move relative to rod 115 in one or more planes while in the unlocked state. With actuation of locking nuts 125 , members 4510 and rod 4515 are immobilized relative to one another. Rod 115 is affixed to fasteners that are attached to the pedicle portion of the lower vertebral level. Rod is freely movable within slot 4517 . In use, the device will preserve vertebral motion but prevent abnormal translational movement that produces spondylolisthesis.
FIG. 49 shows perspective views of an additional device embodiment while FIG. 50 illustrates an exploded view. The present embodiment is similar to the preceding embodiment with the exception of placement of malleable members 131 between the interconnecting rod 4515 and rod 115 . The malleable member biases movement between the vertebral bones towards a default position and resists vertebral movement away from that position. FIG. 51 illustrates an embodiment in which a cavity 242 is placed within each spinous process abutment member in order to accept a bone forming substance. As noted in previous embodiments, this feature would permit device fusion onto the spinous process of the first vertebral bone. Further, a bone graft or bone graft substitute 252 is positioned so that rod 115 transverses a bore within member 252 . This feature permits the establishment of a bony fusion between rod 115 and the lamina or spinous process of the second vertebral bone.
Alternative device embodiments are shown in FIGS. 52 and 53 . In either embodiment, the device is adopted to fixate three vertebral bones. In the embodiment of FIG. 52 , the device anchors onto the spinous process of the middle vertebral level. Rod 890 is attached to bone fasteners that are anchored into the pedicle portion of the lower vertebral level. Rod 890 is freely movable within slot 892 of the spinous process attachment member. Rod 902 is attached to bone fasteners that are anchored into the pedicle portion of the upper vertebral level. Rod 902 is freely movable within slot 904 of the spinous process attachment member. In the embodiment of FIG. 53 , rod 902 is freely movable within slot 904 whereas arms 888 rigidly attach onto the spinous process attachment member using the same mechanism as that shown in FIG. 11 . In use, the embodiment of FIG. 53 provides rigid fixation between the middle and lower vertebral levels while permitting movement between the upper and middle vertebral levels.
A perspective view of an additional embodiment is illustrated in FIG. 54 . Multiple orthogonal views are shown in FIG. 55 while an exploded, view is shown in FIG. 56 . Interconnecting rod 2012 has articulation member 2014 on each end. The spinous process engagement members and the locking mechanism of the device are similar to prior embodiments, such as that of FIG. 45 . Rod 2022 is attached to bone fasteners anchored into the pedicle portion of the lower vertebral bone. Rod 2022 has triangular projections 2024 that articulate with articulation members 2014 of rod 2012 . The embodiment provides controlled movement between the two vertebral bones.
A perspective view of an additional embodiment is shown in FIG. 57 . Exploded views are shown in FIG. 58 and a cross-sectional view through the articulation surface is illustrated in FIG. 59 . While similar to the prior embodiment, this device employs a different articulation mechanism. Spherical members 2106 are contained at the end of interconnecting rod 2102 . Two complimentary articulation surfaces 2112 are attached to rod 2114 . As shown in the cross-sectional view, the complimentary articulation surface 2112 contains a depression adapted to accept spherical member 2106 and, preferably, the depression is larger spherical member 2106 so as to permit some additional translational movement. That is, the articulations form a “loose” joint.
FIG. 60A illustrates the posterior aspect of spine model whereas FIG. 60B shows the placement of bone forming material between the lamina of the L4 and L5 bones. The bone forming material may be an actual bone graft that is cut to the shape illustrated or a device adapted to contain bone graft or bone graft substitute. FIGS. 61A and B show perspective and orthogonal views of an exemplary graft containment device. As shown, the device preferably has a solid bottom that keeps the contained bone forming material form impinging upon the nerve elements. The sides may be open or solid. The top is preferably open and contains side protrusions 2302 that prevent anterior migration of the device into the spinal canal. An alternative device configuration is shown in FIG. 62 . The latter device is intended to cross the vertebral midline, whereas the former is placed on either side of the vertebral midline.
The disclosed devices or any of their components can be made of any biologically adaptable or compatible materials. Materials considered acceptable for biological implantation are well known and include, but are not limited to, stainless steel, titanium, tantalum, shape memory alloys, combination metallic alloys, various plastics, resins, ceramics, biologically absorbable materials and the like. Any components may be also coated/made with osteo-conductive (such as deminerized bone matrix, hydroxyapatite, and the like) and/or osteo-inductive (such as Transforming Growth Factor “TGF-B,” Platelet-Derived Growth Factor “PDGF,” Bone-Morphogenic Protein “BMP,” and the like) bio-active materials that promote bone formation. Further, any surface may be made with a porous ingrowth surface (such as titanium wire mesh, plasma-sprayed titanium, tantalum, porous CoCr, and the like), provided with a bioactive coating, made using tantalum, and/or helical rosette carbon nanotubes (or other nanotube-based materials) in order to promote bone in-growth or establish a mineralized connection between the bone and the implant, and reduce the likelihood of implant loosening. Lastly, the system or any of its components can also be entirely or partially made of a shape memory material or other deformable material.
Although embodiments of various methods and devices are described herein in detail with reference to certain versions, it should be appreciated that other versions, embodiments, methods of use, and combinations thereof are also possible. At a minimum, any feature illustrates in one device embodiment may be alternatively incorporated within any other device embodiment. Therefore the spirit and scope of the appended claims should not be strictly limited to the description of the embodiments contained herein. | Devices and methods are adapted to permit fixation and stabilization of the bony elements of the skeleton. The devices permit adjustment and maintenance of the spatial relationship between neighboring bones. The motion between adjacent skeletal segments may be maintained, limited or completely eliminated. | 0 |
TECHNICAL FIELD
[0001] The present invention relates to electrically variable transmissions with selective operation both in power-split variable speed ratio ranges and in fixed speed ratios, and having two planetary gear sets, two motor/generators and five torque transfer devices.
BACKGROUND OF THE INVENTION
[0002] Internal combustion engines, particularly those of the reciprocating piston type, currently propel most vehicles. Such engines are relatively efficient, compact, lightweight, and inexpensive mechanisms by which to convert highly concentrated energy in the form of fuel into useful mechanical power. A novel transmission system, which can be used with internal combustion engines and which can reduce fuel consumption and the emissions of pollutants, may be of great benefit to the public.
[0003] The wide variation in the demands that vehicles typically place on internal combustion engines increases fuel consumption and emissions beyond the ideal case for such engines. Typically, a vehicle is propelled by such an engine, which is started from a cold state by a small electric motor and relatively small electric storage batteries, then quickly placed under the loads from propulsion and accessory equipment. Such an engine is also operated through a wide range of speeds and a wide range of loads and typically at an average of approximately a fifth of its maximum power output.
[0004] A vehicle transmission typically delivers mechanical power from an engine to the remainder of a drive system, such as fixed final drive gearing, axles and wheels. A typical mechanical transmission allows some freedom in engine operation, usually through alternate selection of five or six different drive ratios, a neutral selection that allows the engine to operate accessories with the vehicle stationary, and clutches or a torque converter for smooth transitions between driving ratios and to start the vehicle from rest with the engine turning. Transmission gear selection typically allows power from the engine to be delivered to the rest of the drive system with a ratio of torque multiplication and speed reduction, with a ratio of torque reduction and speed multiplication known as overdrive, or with a reverse ratio.
[0005] An electric generator can transform mechanical power from the engine into electrical power, and an electric motor can transform that electric power back into mechanical power at different torques and speeds for the remainder of the vehicle drive system. This arrangement allows a continuous variation in the ratio of torque and speed between engine and the remainder of the drive system, within the limits of the electric machinery. An electric storage battery used as a source of power for propulsion may be added to this arrangement, forming a series hybrid electric drive system.
[0006] The series hybrid system allows the engine to operate with some independence from the torque, speed and power required to propel a vehicle, so the engine may be controlled for improved emissions and efficiency. This system allows the electric machine attached to the engine to act as a motor to start the engine. This system also allows the electric machine attached to the remainder of the drive train to act as a generator, recovering energy from slowing the vehicle into the battery by regenerative braking. A series electric drive suffers from the weight and cost of sufficient electric machinery to transform all of the engine power from mechanical to electrical in the generator and from electrical to mechanical in the drive motor, and from the useful energy lost in these conversions.
[0007] A power-split transmission can use what is commonly understood to be “differential gearing” to achieve a continuously variable torque and speed ratio between input and output. An electrically variable transmission can use differential gearing to send a fraction of its transmitted power through a pair of electric motor/generators. The remainder of its power flows through another, parallel path that is all mechanical and direct, of fixed ratio, or alternatively selectable.
[0008] One form of differential gearing, as is well known to those skilled in this art, may constitute a planetary gear set. Planetary gearing is usually the preferred embodiment employed in differentially geared inventions, with the advantages of compactness and different torque and speed ratios among all members of the planetary gear set. However, it is possible to construct this invention without planetary gears, as by using bevel gears or other gears in an arrangement where the rotational speed of at least one element of a gear set is always a weighted average of speeds of two other elements.
[0009] A hybrid electric vehicle transmission system also includes one or more electric energy storage devices. The typical device is a chemical electric storage battery, but capacitive or mechanical devices, such as an electrically driven flywheel, may also be included. Electric energy storage allows the mechanical output power from the transmission system to the vehicle to vary from the mechanical input power from the engine to the transmission system. The battery or other device also allows for engine starting with the transmission system and for regenerative vehicle braking.
[0010] An electrically variable transmission in a vehicle can simply transmit mechanical power from an engine input to a final drive output. To do so, the electric power produced by one motor/generator balances the electrical losses and the electric power consumed by the other motor/generator. By using the above-referenced electrical storage battery, the electric power generated by one motor/generator can be greater than or less than the electric power consumed by the other. Electric power from the battery can sometimes allow both motor/generators to act as motors, especially to assist the engine with vehicle acceleration. Both motors can sometimes act as generators to recharge the battery, especially in regenerative vehicle braking.
[0011] A successful substitute for the series hybrid transmission is the two-range, input-split and compound-split electrically variable transmission now produced for transit buses, as disclosed in U.S. Pat. No. 5,931,757, issued Aug. 3, 1999, to Michael Roland Schmidt, commonly assigned with the present application, and hereby incorporated by reference in its entirety. Such a transmission utilizes an input means to receive power from the vehicle engine and a power output means to deliver power to drive the vehicle. First and second motor/generators are connected to an energy storage device, such as a battery, so that the energy storage device can accept power from, and supply power to, the first and second motor/generators. A control unit regulates power flow among the energy storage device and the motor/generators as well as between the first and second motor/generators.
[0012] Operation in first or second variable-speed-ratio modes of operation may be selectively achieved by using clutches in the nature of first and second torque transfer devices. In the first mode, an input-power-split speed ratio range is formed by the application of the first clutch, and the output speed of the transmission is proportional to the speed of one motor/generator. In the second mode, a compound-power-split speed ratio range is formed by the application of the second clutch, and the output speed of the transmission is not proportional to the speeds of either of the motor/generators, but is an algebraic linear combination of the speeds of the two motor/generators. Operation at a fixed transmission speed ratio may be selectively achieved by the application of both of the clutches. Operation of the transmission in a neutral mode may be selectively achieved by releasing both clutches, decoupling the engine and both electric motor/generators from the transmission output. The transmission incorporates at least one mechanical point in its first mode of operation and at least two mechanical points in its second mode of operation.
[0013] U.S. Pat. No. 6,527,658, issued Mar. 4, 2003 to Holmes et al, commonly assigned with the present application, and hereby incorporated by reference in its entirety, discloses an electrically variable transmission utilizing two planetary gear sets, two motor/generators and two clutches to provide input split, compound split, neutral and reverse modes of operation. Both planetary gear sets may be simple, or one may be individually compounded. An electrical control member regulates power flow among an energy storage device and the two motor/generators. This transmission provides two ranges or modes of electrically variable transmission (EVT) operation, selectively providing an input-power-split speed ratio range and a compound-power-split speed ratio range. One fixed speed ratio can also be selectively achieved.
SUMMARY OF THE INVENTION
[0014] The present invention provides a family of electrically variable transmissions offering several advantages over conventional automatic transmissions for use in hybrid vehicles, including improved vehicle acceleration performance, improved fuel economy via regenerative braking and electric-only idling and launch, and an attractive marketing feature. An object of the invention is to provide the best possible energy efficiency and emissions for a given engine. In addition, optimal performance, capacity, package size, and ratio coverage for the transmission are sought.
[0015] The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first and second differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, and five selectable torque-transfer devices (two clutches and three brakes). Preferably, the differential gear sets are planetary gear sets, but other gear arrangements may be implemented, such as bevel gears or differential gearing to an offset axis.
[0016] In this description, the first or second planetary gear sets may be counted first to second in any order (i.e., left to right or right to left).
[0017] Each of the two planetary gear sets has three members. The first, second or third member of each planetary gear set can be any one of a sun gear, ring gear or carrier, or alternatively a pinion.
[0018] Each carrier can be either a single-pinion carrier (simple) or a double-pinion carrier (compound).
[0019] The input shaft is continuously connected with at least one member of the planetary gear sets. The output shaft is continuously connected with another member of the planetary gear sets.
[0020] A first torque transfer device selectively connects a member of the first planetary gear set with a member of the second planetary gear set.
[0021] A second torque transfer device selectively connects a member of the first planetary gear set with a member of the second planetary gear set, this pair of members being different from the ones connected by the first torque transfer device.
[0022] A third torque transfer device selectively connects a member of the first or second planetary gear set with a stationary member (ground/transmission case).
[0023] A fourth torque transfer device is connected in parallel with one of the motor/generators for selectively preventing rotation of the motor/generator.
[0024] A fifth torque transfer device is connected in parallel with the other of the motor/generators for selectively preventing rotation thereof.
[0025] The first motor/generator is mounted to the transmission case (or ground) and is continuously connected to a member of the first or second planetary gear set.
[0026] The second motor/generator is mounted to the transmission case and is continuously connected to a member of the second planetary gear set, this member being different from the one continuously connected to the first motor/generator.
[0027] The five selectable torque transfer devices (two clutches and three brakes) are engaged singly or in combinations of two or three to yield an EVT with a continuously variable range of speeds (including reverse) and up to three mechanically fixed forward speed ratios. A “fixed speed ratio” is an operating condition in which the mechanical power input to the transmission is transmitted mechanically to the output, and no power flow (i.e. almost zero) is present in the motor/generators. An electrically variable transmission that may selectively achieve several fixed speed ratios for operation near full engine power can be smaller and lighter for a given maximum capacity. Fixed ratio operation may also result in lower fuel consumption when operating under conditions where engine speed can approach its optimum without using the motor/generators. A variety of fixed speed ratios and variable ratio spreads can be realized by suitably selecting the tooth ratios of the planetary gear sets.
[0028] Each embodiment of the electrically variable transmission family disclosed has an architecture in which neither the transmission input nor output is directly connected to a motor/generator. This allows for a reduction in the size and cost of the electric motor/generators required to achieve the desired vehicle performance.
[0029] The torque transfer devices, and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.
[0030] The above features and advantages, and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 a is a schematic representation of a powertrain including an electrically variable transmission incorporating a family member of the present invention;
[0032] FIG. 1 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 1 a;
[0033] FIG. 2 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0034] FIG. 2 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 2 a;
[0035] FIG. 3 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0036] FIG. 3 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 3 a;
[0037] FIG. 4 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0038] FIG. 4 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 4 a;
[0039] FIG. 5 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0040] FIG. 5 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 5 a;
[0041] FIG. 6 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0042] FIG. 6 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 6 a;
[0043] FIG. 7 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention;
[0044] FIG. 7 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 7 a;
[0045] FIG. 8 a is a schematic representation of a powertrain having an electrically variable transmission incorporating another family member of the present invention; and
[0046] FIG. 8 b is an operating mode table and fixed ratio mode table depicting some of the operating characteristics of the powertrain shown in FIG. 8 a.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] With reference to FIG. 1 a , a powertrain 10 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission (EVT), designated generally by the numeral 14 . Transmission 14 is designed to receive at least a portion of its driving power from the engine 12 . As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 14 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0048] In the embodiment depicted the engine 12 may be a fossil fuel engine, such as a diesel engine which is readily adapted to provide its available power output typically delivered at a constant number of revolutions per minute (RPM).
[0049] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 14 .
[0050] An output member 19 of the transmission 14 is connected to a final drive 16 .
[0051] The transmission 14 utilizes two differential gear sets, preferably in the nature of planetary gear sets 20 and 30 . The planetary gear set 20 employs an outer gear member 24 , typically designated as the ring gear. The ring gear member 24 circumscribes an inner gear member 22 , typically designated as the sun gear. A carrier member 26 rotatably supports a plurality of planet gears 27 such that each planet gear 27 meshingly engages both the outer, ring gear member 24 and the inner, sun gear member 22 of the first planetary gear set 20 .
[0052] The planetary gear set 30 also has an outer gear member 34 , often also designated as the ring gear that circumscribes an inner gear member 32 , also often designated as the sun gear member. A plurality of planet gears 37 are also rotatably mounted in a carrier member 36 such that each planet gear member 37 simultaneously, and meshingly, engages both the outer, ring gear member 34 and the inner, sun gear member 32 of the planetary gear set 30 .
[0053] The first preferred embodiment 10 also incorporates first and second motor/generators 80 and 82 , respectively. The stator of the first motor/generator 80 is secured to the transmission housing 60 . The rotor of the first motor/generator 80 is secured to the sun gear member 22 of the planetary gear set 20 .
[0054] The stator of the second motor/generator 82 is also secured to the transmission housing 60 . The rotor of the second motor/generator 82 is secured to the sun gear member 32 of the planetary gear set 30 .
[0055] A first torque transfer device, such as a clutch 50 , selectively connects the sun gear member 22 of the planetary gear set 20 to the ring gear member 34 of the planetary gear set 30 . A second torque transfer device, such as clutch 52 , selectively connects the ring gear member 24 of the planetary gear set 20 with the sun gear member 32 of the planetary gear set 30 . A third torque transfer device, such as brake 54 , selectively connects the ring gear member 34 of the planetary gear set 30 with the transmission housing 60 . That is, the ring gear member 34 is selectively secured against rotation by an operative connection to the non-rotatable housing 60 . A fourth torque transfer device, such as the brake 55 , is connected in parallel with the motor/generator 80 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 57 , is connected in parallel with the motor/generator 82 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque transfer devices 50 , 52 , 54 , 55 and 57 are employed to assist in the selection of the operational modes of the hybrid transmission 14 , as will be hereinafter more fully explained.
[0056] The transmission input member 17 is connected with the carrier member 26 of the planetary gear set 20 . The output drive member 19 of the transmission 14 is secured to the carrier member 36 of the planetary gear set 30 .
[0057] Returning now to the description of the power sources, it should be apparent from the foregoing description, and with particular reference to FIG. 1 a , that the transmission 14 selectively receives power from the engine 12 . The hybrid transmission also receives power from an electric power source 86 , which is operably connected to a controller 88 . The electric power source 86 may be one or more batteries. Other electric power sources, such as fuel cells, that have the ability to provide, or store, and dispense electric power may be used in place of batteries without altering the concepts of the present invention.
[0000] General Operating Considerations
[0058] One of the primary control devices is a well known drive range selector (not shown) that directs an electronic control unit (the ECU 88 ) to configure the transmission for either the park, reverse, neutral, or forward drive range. The second and third primary control devices constitute an accelerator pedal (not shown) and a brake pedal (also not shown). The information obtained by the ECU from these three primary control sources is designated as the “operator demand.” The ECU also obtains information from a plurality of sensors (input as well as output) as to the status of: the torque transfer devices (either applied or released); the engine output torque; the unified battery, or batteries, capacity level; and, the temperatures of selected vehicular components. The ECU determines what is required and then manipulates the selectively operated components of, or associated with, the transmission appropriately to respond to the operator demand.
[0059] The invention may use simple or compound planetary gear sets. In a simple planetary gear set a single set of planet gears are normally supported for rotation on a carrier that is itself rotatable.
[0060] In a simple planetary gear set, when the sun gear is held stationary and power is applied to the ring gear of a simple planetary gear set, the planet gears rotate in response to the power applied to the ring gear and thus “walk” circumferentially about the fixed sun gear to effect rotation of the carrier in the same direction as the direction in which the ring gear is being rotated.
[0061] When any two members of a simple planetary gear set rotate in the same direction and at the same speed, the third member is forced to turn at the same speed, and in the same direction. For example, when the sun gear and the ring gear rotate in the same direction, and at the same speed, the planet gears do not rotate about their own axes but rather act as wedges to lock the entire unit together to effect what is known as direct drive. That is, the carrier rotates with the sun and ring gears.
[0062] However, when the two gear members rotate in the same direction, but at different speeds, the direction in which the third gear member rotates may often be determined simply by visual analysis, but in many situations the direction will not be obvious and can only be accurately determined by knowing the number of teeth present on all the gear members of the planetary gear set.
[0063] Whenever the carrier is restrained from spinning freely, and power is applied to either the sun gear or the ring gear, the planet gear members act as idlers. In that way the driven member is rotated in the opposite direction as the drive member. Thus, in many transmission arrangements when the reverse drive range is selected, a torque transfer device serving as a brake is actuated frictionally to engage the carrier and thereby restrain it against rotation so that power applied to the sun gear will turn the ring gear in the opposite direction. Thus, if the ring gear is operatively connected to the drive wheels of a vehicle, such an arrangement is capable of reversing the rotational direction of the drive wheels, and thereby reversing the direction of the vehicle itself.
[0064] In a simple set of planetary gears, if any two rotational speeds of the sun gear, the planet carrier, and the ring gear are known, then the speed of the third member can be determined using a simple rule. The rotational speed of the carrier is always proportional to the speeds of the sun and the ring, weighted by their respective numbers of teeth. For example, a ring gear may have twice as many teeth as the sun gear in the same set. The speed of the carrier is then the sum of two-thirds the speed of the ring gear and one-third the speed of the sun gear. If one of these three members rotates in an opposite direction, the arithmetic sign is negative for the speed of that member in mathematical calculations.
[0065] The torque on the sun gear, the carrier, and the ring gear can also be simply related to one another if this is done without consideration of the masses of the gears, the acceleration of the gears, or friction within the gear set, all of which have a relatively minor influence in a well designed transmission. The torque applied to the sun gear of a simple planetary gear set must balance the torque applied to the ring gear, in proportion to the number of teeth on each of these gears. For example, the torque applied to a ring gear with twice as many teeth as the sun gear in that set must be twice that applied to the sun gear, and must be applied in the same direction. The torque applied to the carrier must be equal in magnitude and opposite in direction to the sum of the torque on the sun gear and the torque on the ring gear.
[0066] In a compound planetary gear set, the utilization of inner and outer sets of planet gears effects an exchange in the roles of the ring gear and the planet carrier in comparison to a simple planetary gear set. For instance, if the sun gear is held stationary, the planet carrier will rotate in the same direction as the ring gear, but the planet carrier with inner and outer sets of planet gears will travel faster than the ring gear, rather than slower.
[0067] In a compound planetary gear set having meshing inner and outer sets of planet gears the speed of the ring gear is proportional to the speeds of the sun gear and the planet carrier, weighted by the number of teeth on the sun gear and the number of teeth filled by the planet gears, respectively. For example, the difference between the ring and the sun filled by the planet gears might be as many teeth as are on the sun gear in the same set. In that situation the speed of the ring gear would be the sum of two-thirds the speed of the carrier and one third the speed of the sun. If the sun gear or the planet carrier rotates in an opposite direction, the arithmetic sign is negative for that speed in mathematical calculations.
[0068] If the sun gear were to be held stationary, then a carrier with inner and outer sets of planet gears will turn in the same direction as the rotating ring gear of that set. On the other hand, if the sun gear were to be held stationary and the carrier were to be driven, then planet gears in the irmer set that engage the sun gear roll, or “walk,” along the sun gear, turning in the same direction that the carrier is rotating. Pinion gears in the outer set that mesh with pinion gears in the inner set will turn in the opposite direction, thus forcing a meshing ring gear in the opposite direction, but only with respect to the planet gears with which the ring gear is meshingly engaged. The planet gears in the outer set are being carried along in the direction of the carrier. The effect of the rotation of the pinion gears in the outer set on their own axis and the greater effect of the orbital motion of the planet gears in the outer set due to the motion of the carrier are combined, so the ring rotates in the same direction as the carrier, but not as fast as the carrier.
[0069] If the carrier in such a compound planetary gear set were to be held stationary and the sun gear were to be rotated, then the ring gear will rotate with less speed and in the same direction as the sun gear. If the ring gear of a simple planetary gear set is held stationary and the sun gear is rotated, then the carrier supporting a single set of planet gears will rotate with less speed and in the same direction as the sun gear. Thus, one can readily observe the exchange in roles between the carrier and the ring gear that is caused by the use of inner and outer sets of planet gears which mesh with one another, in comparison with the usage of a single set of planet gears in a simple planetary gear set.
[0070] The normal action of an electrically variable transmission is to transmit mechanical power from the input to the output. As part of this transmission action, one of its two motor/generators acts as a generator of electrical power. The other motor/generator acts as a motor and uses that electrical power. As the speed of the output increases from zero to a high speed, the two motor/generators 80 , 82 gradually exchange roles as generator and motor, and may do so more than once. These exchanges take place around mechanical points, where essentially all of the power from input to output is transmitted mechanically and no substantial power is transmitted electrically.
[0071] In a hybrid electrically variable transmission system, the battery 86 may also supply power to the transmission or the transmission may supply power to the battery. If the battery is supplying substantial electric power to the transmission, such as for vehicle acceleration, then both motor/generators may act as motors. If the transmission is supplying electric power to the battery, such as for regenerative braking, both motor/generators may act as generators. Very near the mechanical points of operation, both motor/generators may also act as generators with small electrical power outputs, because of the electrical losses in the system.
[0072] Contrary to the normal action of the transmission, the transmission may actually be used to transmit mechanical power from the output to the input. This may be done in a vehicle to supplement the vehicle brakes and to enhance or to supplement regenerative braking of the vehicle, especially on long downward grades. If the power flow through the transmission is reversed in this way, the roles of the motor/generators will then be reversed from those in normal action.
[0000] Specific Operating Considerations
[0073] Each of the embodiments described herein has fourteen or fifteen functional requirements (corresponding with the 14 or 15 rows of each operating mode table shown in the Figures) which may be grouped into five operating modes. These five operating modes are described below and may be best understood by referring to the respective operating mode table accompanying each transmission stick diagram, such as the operating mode tables of FIGS. 1 b , 2 b , 3 b , etc.
[0074] The first operating mode is the “battery reverse mode” which corresponds with the first row (Batt Rev) of each operating mode table, such as that of FIG. 1 b . In this mode, the engine is off and the transmission element connected to the engine is not controlled by engine torque, though there may be some residual torque due to the rotational inertia of the engine. The EVT is driven by one of the motor/generators using energy from the battery, causing the vehicle to move in reverse. Depending on the kinematic configuration, the other/motor/generator may or may not rotate in this mode, and may or may not transmit torque. If it does rotate, it is used to generate energy which is stored in the battery. In the embodiment of FIG. 1 b , in the battery reverse mode, the brake 54 is engaged, the generator 80 has zero torque, the motor 82 has a torque of −1.00 units, and a torque ratio of −2.88 is achieved, corresponding to an engine input torque of 1 unit, by way of example. In each operating mode table an (M) next to a torque value in the motor/generator columns 80 and 82 indicates that the motor/generator is acting as a motor, and the absence of an (M) indicates that the motor/generator is acting as generator.
[0075] The second operating mode is the “EVT reverse mode” (or mechanical reverse mode) which corresponds with the second row (EVT Rev) of each operating mode table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine and by one of the motor/generators. The other motor/generator operates in generator mode and transfers 100% of the generated energy back to the driving motor. The net effect is to drive the vehicle in reverse. Referring to FIG. 1 b , for example, in the EVT reverse mode, the clutch 52 and brake 54 are engaged, the generator 80 has a torque of −0.35 units, the motor 82 has a torque of −3.55 units, and an output torque of −8.33 is achieved, corresponding to an engine torque of 1 unit.
[0076] The third operating mode includes the “reverse and forward launch modes” (also referred to as “torque converter reverse and forward modes”) corresponding with the third and fourth rows (TC Rev and TC For) of each operating mode table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine and one of the motor/generators. A selectable fraction of the energy generated in the generator unit is stored in the battery, with the remaining energy being transferred to the motor. In FIG. 1 , this fraction is approximately 99%. The ratio of transmission output speed to engine speed (transmission speed ratio) is approximately +/−0.001 (the positive sign indicates that the vehicle is creeping forward and negative sign indicates that the vehicle is creeping backwards). Referring to FIG. 1 b , in the reverse and forward launch modes, the clutch 52 and brake 54 are engaged. In the TC Reverse mode, the motor/generator 80 acts as a generator with −0.35 units of torque, the motor/generator 82 acts as a motor with −3.09 units of torque, and a torque ratio of −7.00 is achieved. In the TC Forward mode, the motor/generator 80 acts as a generator with −0.35 units of torque, the motor/generator 82 acts as a motor with 0.98 units of torque, and a torque ratio of 4.69 is achieved.
[0077] The fourth operating mode is a “continuously variable transmission range mode” which includes the Range 1 . 1 , Range 1 . 2 , Range 1 . 3 , Range 1 . 4 , Range 2 . 1 , Range 2 . 2 , Range 2 . 3 and Range 2 . 4 operating points corresponding with rows 5 - 12 of each operating point table, such as that of FIG. 1 b . In this mode, the EVT is driven by the engine as well as one of the motor/generators operating as a motor. The other motor/generator operates as a generator and transfers 100% of the generated energy back to the motor. The operating points represented by Range 1 . 1 , 1 . 2 , . . . , etc. are discrete points in the continuum of forward speed ratios provided by the EVT. For example in FIG. 1 b , a range of torque ratios from 4.69 to 1.86 is achieved with the clutch 52 and brake 54 engaged, and a range of ratios 1.36 to 0.54 is achieved with the clutches 50 and 52 engaged.
[0078] The fifth operating mode includes the “fixed ratio” modes (F 1 and F 2 ) corresponding with rows 13 - 14 of each operating mode table (i.e. operating mode table), such as that of FIG. 1 b . In this mode the transmission operates like a conventional automatic transmission, with three torque transfer devices engaged to create a discrete transmission ratio. The clutching table accompanying each figure shows only 2 fixed-ratio forward speeds but additional fixed ratios may be available. Referring to FIG. 1 b , in fixed ratio F 1 the clutch 52 and brakes 54 , 55 are engaged to achieve a fixed torque ratio of 1.88. Accordingly, each “X” in the column of motor/generators 80 , 82 in FIG. 1 b indicates that the respective brake 55 or 57 is engaged and the motor/generators 80 or 82 is not rotating. In fixed ratio F 2 , the clutches 50 , 52 and brake 57 are engaged to achieve a fixed ratio of 0.53.
[0079] The transmission 14 is capable of operating in so-called single or dual modes. In single mode, the engaged torque transfer device remains the same for the entire continuum of forward speed ratios (represented by the discrete points: Ranges 1.1, 1.2, 1.3 and 1.4). In dual mode, the engaged torque transfer device is switched at some intermediate speed ratio (e.g., Range 2 . 1 in FIG. 1 ). Depending on the mechanical configuration, this change in torque transfer device engagement has advantages in reducing element speeds in the transmission.
[0080] In some designs, it is possible to synchronize clutch element slip speeds such that shifts are achievable with minimal torque disturbance (so-called “cold” shifts). For example, the transmissions of FIGS. 1 a , 2 a , 3 a , 4 a and 5 a have cold shifts between ranges 1 . 4 and 2 . 1 . This also serves as an enabler for superior control during double transition shifts (two oncoming clutches and two off-going clutches).
[0081] As set forth above, the engagement schedule for the torque transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 1 b . FIG. 1 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 1 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 20 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 30 . Also, the chart of FIG. 1 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 3.55.
Description of a Second Exemplary Embodiment
[0082] With reference to FIG. 2 a , a powertrain 110 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission, designated generally by the numeral 114 . Transmission 114 is designed to receive at least a portion of its driving power from the engine 12 .
[0083] In the embodiment depicted the engine 12 may also be a fossil fuel engine, such as a diesel engine which is readily adapted to provide its available power output typically delivered at a constant number of revolutions per minute (RPM). As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 114 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0084] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 114 . An output member 19 of the transmission 114 is connected to a final drive 16 .
[0085] The transmission 114 utilizes two differential gear sets, preferably in the nature of planetary gear sets 120 and 130 . The planetary gear set 120 employs an outer gear member 124 , typically designated as the ring gear. The ring gear member 124 circumscribes an inner gear member 122 , typically designated as the sun gear. A carrier member 126 rotatably supports a plurality of planet gears 127 such that each planet gear 127 meshingly engages both the outer, ring gear member 124 and the inner, sun gear member 122 of the first planetary gear set 120 .
[0086] The planetary gear set 130 also has an outer gear member 134 , often also designated as the ring gear, that circumscribes an inner gear member 132 , also often designated as the sun gear. A plurality of planet gears 137 are also rotatably mounted in a carrier member 136 such that each planet gear member 137 simultaneously, and meshingly, engages both the outer, ring gear member 134 and the inner, sun gear member 132 of the planetary gear set 130 .
[0087] The transmission input member 17 is connected with the carrier member 126 of the planetary gear set 120 , and the transmission output member 19 is connected with the carrier member 136 of the planetary gear set 130 .
[0088] The transmission 114 also incorporates first and second motor/generators 180 and 182 , respectively. The stator of the first motor/generator 180 is secured to the transmission housing 160 . The rotor of the first motor/generator 180 is secured to the sun gear member 122 of the planetary gear set 120 .
[0089] The stator of the second motor/generator 182 is also secured to the transmission housing 160 . The rotor of the second motor/generator 182 is secured to the ring gear member 134 of the planetary gear set 130 .
[0090] A first torque transfer device, such as a clutch 150 , selectively connects the carrier member 126 of the planetary gear set 120 to the ring gear member 134 of the planetary gear set 130 . A second torque transfer device, such as clutch 152 , selectively connects the ring gear member 124 of the planetary gear set 120 with the sun gear member 132 of the planetary gear set 130 . A third torque transfer device, such as brake 154 , selectively connects the sun gear member 132 of the planetary gear set 130 with the transmission housing 160 . That is, the sun gear member 132 is selectively secured against rotation by an operative connection to the non-rotatable housing 160 . A fourth torque transfer device, such as the brake 155 , is connected in parallel with the motor/generator 180 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 157 , is connected in parallel with the motor/generator 182 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque transfer devices 150 , 152 , 154 , 155 and 157 are employed to assist in the selection of the operational modes of the hybrid transmission 114 .
[0091] Returning now to the description of the power sources, it should be apparent from the foregoing description, and with particular reference to FIG. 2 a , that the transmission 114 selectively receives power from the engine 12 . The hybrid transmission also exchanges power with an electric power source 186 , which is operably connected to a controller 188 . The electric power source 186 may be one or more batteries. Other electric power sources, such as fuel cells, that have the ability to provide, or store, and dispense electric power may be used in place of batteries without altering the concepts of the present invention.
[0092] As described previously, each embodiment has fourteen or fifteen functional requirements (corresponding with the 14 or 15 rows of each operating mode table shown in the Figures) which may be grouped into five operating modes. The first operating mode is the “battery reverse mode” which corresponds with the first row (Batt Rev) of the operating mode table of FIG. 2 b . In this mode, the engine is off and the transmission element connected to the engine is effectively allowed to freewheel, subject to engine inertia torque. The EVT is driven by one of the motor/generators using energy from the battery, causing the vehicle to move in reverse. The other motor/generator may or may not rotate in this mode. As shown in FIG. 2 b , in this mode the brake 154 is engaged, the motor/generator 180 has zero torque, the motor 182 has a torque of −1.00 unit and an output torque of −1.50 is achieved, by way of example.
[0093] The second operating mode is the “EVT reverse mode” (or mechanical reverse mode) which corresponds with the second row (EVT Rev) of the operating mode table of FIG. 2 b . In this mode, the EVT is driven by the engine and by one of the motor/generators. The other motor/generator operates in generator mode and transfers 100% of the generated energy back to the driving motor. The net effect is to drive the vehicle in reverse. In this mode, the clutch 152 and brake 154 are engaged, the generator 180 has a torque of −0.25 units, the motor 182 has a torque of −5.55 units, and an output torque of −8.33 is achieved, corresponding to an input torque of 1 unit.
[0094] The third operating mode includes the “reverse and forward launch modes” corresponding with the third and fourth rows (TC Rev and TC For) of each operating mode table, such as that of FIG. 2 b . In this mode, the EVT is driven by the engine and one of the motor/generators. A selectable fraction of the energy generated in the generator unit is stored in the battery, with the remaining energy being transferred to the motor. In this mode, the clutch 152 and the brake 154 are engaged, and the motor/generator 180 acts as a generator (with −0.25 units of torque in reverse and forward), the motor/generator 182 acts as a motor in TC Reverse with −4.67 units of torque, and as a motor in TC Forward with 3.13 units of, and a torque ratio of −7.00 (TC reverse) or 4.69 (TC forward) is achieved. For these torque ratios, approximately 99% of the generator energy is stored in the battery.
[0095] The fourth operating mode includes the “Range 1 . 1 , Range 1 . 2 , Range 1 . 3 , Range 1 . 4 , Range 2 . 1 , Range 2 . 2 , Range 2 . 3 and Range 2 . 4 ” modes corresponding with rows 5 - 12 of the operating mode table of FIG. 2 b . In this mode, the EVT is driven by the engine as well as one of the motor/generators operating as a motor. The other motor/generator operates as a generator and transfers 100% of the generated energy back to the motor. The operating points represented by Range 1 . 1 , 1 . 2 , . . . , etc. are discrete points in the continuum of forward speed ratios provided by the EVT. For example in FIG. 2 b , a range of ratios from 4.69 to 1.86 is achieved with the clutch 152 and the brake 154 engaged, and a range of ratios from 1.36 to 0.54 is achieved with the clutches 150 and 152 engaged.
[0096] The fifth operating mode includes the fixed “ratio” modes (F 1 , F 2 and F 3 ) corresponding with rows 13 - 15 of the operating mode table of FIG. 2 b . In this mode the transmission operates like a conventional automatic transmission, with three torque transfer devices engaged to create a discrete transmission ratio. In fixed ratio F 1 the clutch 152 and brakes 154 and 155 are engaged to achieve a fixed ratio of 2.24. In fixed ratio F 2 , the clutch 150 and brakes 155 and 157 are engaged to achieve a fixed ratio of 1.50. In fixed ratio F 3 , the clutches 150 , 152 and brake 155 are engaged to achieve a fixed ratio of 0.90.
[0097] As set forth above, the engagement schedule for the torque transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 2 b . FIG. 2 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 2 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 120 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 130 . Also, the chart of FIG. 2 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.49, the step ratio between the second and third fixed forward torque ratios is 1.67.
Description of a Third Exemplary Embodiment
[0098] With reference to FIG. 3 a , a powertrain 210 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission, designated generally by the numeral 214 . The transmission 214 is designed to receive at least a portion of its driving power from the engine 12 . As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 214 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission 214 .
[0099] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member is operatively connected to a planetary gear set in the transmission 214 . An output member 19 of the transmission 214 is connected to a final drive 16 .
[0100] The transmission 214 utilizes two differential gear sets, preferably in the nature of planetary gear sets 220 and 230 . The planetary gear set 220 employs an outer gear member 224 , typically designated as the ring gear. The ring gear member 224 circumscribes an inner gear member 222 , typically designated as the sun gear. A carrier member 226 rotatably supports a plurality of planet gears 227 such that each planet gear 227 meshingly engages both the outer, ring gear member 224 and the inner, sun gear member 222 of the first planetary gear set 220 .
[0101] The planetary gear set 230 also has an outer ring gear member 234 that circumscribes an inner sun gear member 232 . A plurality of planet gears 237 , 238 are also rotatably mounted in a carrier member 236 such that each planet gear member 237 meshingly engages the sun gear member 232 , and each planet gear 238 meshingly engages the ring gear member 234 , while the planet gears 237 and 238 meshingly engage each other.
[0102] The transmission input member 17 is connected with the carrier member 226 , and the transmission output member 19 is connected to the ring gear member 234 .
[0103] The transmission 214 also incorporates first and second motor/generators 280 and 282 , respectively. The stator of the first motor/generator 280 is secured to the transmission housing 260 . The rotor of the first motor/generator 280 is secured to the sun gear member 222 of the planetary gear set 220 .
[0104] The stator of the second motor/generator 282 is also secured to the transmission housing 260 . The rotor of the second motor/generator 282 is secured to the sun gear member 232 of the planetary gear set 230 .
[0105] A first torque-transfer device, such as clutch 250 , selectively connects the carrier member 226 of the planetary gear set 220 with the carrier member 236 of the planetary gear set 230 . A second torque-transfer device, such as clutch 252 , selectively connects the ring gear member 224 of the planetary gear set 220 with the sun gear member 232 of the planetary gear set 230 . A third torque-transfer device, such as a brake 254 , selectively connects the carrier member 236 with the transmission housing 260 . A fourth torque transfer device, such as the brake 255 , is connected in parallel with the motor/generator 280 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 257 , is connected in parallel with the motor/generator 282 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque-transfer devices 250 , 252 , 254 , 255 and 257 are employed to assist in the selection of the operational modes of the hybrid transmission 214 .
[0106] The hybrid transmission 214 receives power from the engine 12 , and also from electric power source 286 , which is operably connected to a controller 288 .
[0107] The operating mode table of FIG. 3 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 214 . These modes include the “battery reverse mode” (Batt Rev), “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “range 1 . 1 , 1 . 2 , 1 . 3 . . . modes” and “fixed ratio modes” (F 1 , F 2 and F 3 ) as described previously.
[0108] As set forth above the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 3 b . FIG. 3 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 3 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 220 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 230 . Also, the chart of FIG. 3 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between the first and second fixed forward torque ratios is 1.49, the step ratio between the second and third fixed forward torque ratios 1.67.
Description of a Fourth Exemplary Embodiment
[0109] With reference to FIG. 4 a , a powertrain 310 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission, designated generally by the numeral 314 . The transmission 314 is designed to receive at least a portion of its driving power from the engine 12 .
[0110] As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 314 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0111] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 314 . An output member 19 of the transmission 314 is connected to a final drive 16 .
[0112] The transmission 314 utilizes two planetary gear sets 320 and 330 . The planetary gear set 320 employs an outer ring gear member 324 which circumscribes an inner sun gear member 322 . A carrier member 326 rotatably supports a plurality of planet gears 327 such that each planet gear 327 meshingly engages both the outer ring gear member 324 and the inner sun gear member 322 of the first planetary gear set 320 .
[0113] The planetary gear set 330 also has an outer ring gear member 334 that circumscribes an inner sun gear member 332 . A plurality of planet gears 337 are also rotatably mounted in a carrier member 336 such that each planet gear member 337 simultaneously, and meshingly engages both the outer, ring gear member 334 and the inner, sun gear member 332 of the planetary gear set 330 .
[0114] The transmission input member 17 is connected with the carrier member 326 of the planetary gear set 320 , and the transmission output member 19 is connected with the carrier member 336 of the planetary gear set 330 .
[0115] The transmission 314 also incorporates first and second motor/generators 380 and 382 , respectively. The stator of the first motor/generator 380 is secured to the transmission housing 360 . The rotor of the first motor/generator 380 is secured to the sun gear member 322 of the planetary gear set 320 . The stator of the second motor/generator 382 is also secured to the transmission housing 360 . The rotor of the second motor/generator 382 is secured to the sun gear member 332 of the planetary gear set 330 .
[0116] A first torque-transfer device, such as the clutch 350 , selectively connects the carrier member 326 of the planetary gear set 320 with the ring gear member 334 of the planetary gear set 330 . A second torque-transfer device, such as the clutch 352 , selectively connects the ring gear member 324 with the sun gear member 332 . A third torque-transfer device, such as brake 354 , selectively connects the ring gear member 334 with the transmission housing 360 . A fourth torque transfer device, such as the brake 355 , is connected in parallel with the motor/generator 380 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 357 , is connected in parallel with the motor/generator 382 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque-transfer devices 350 , 352 , 354 , 355 and 357 are employed to assist in the selection of the operational modes of the transmission 314 .
[0117] The hybrid transmission 314 receives power from the engine 12 , and also exchanges power with an electric power source 386 , which is operably connected to a controller 388 .
[0118] The operating mode table of FIG. 4 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 314 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 , F 3 ) as described previously.
[0119] As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 4 b . FIG. 4 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 4 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 320 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 330 . Also, the chart of FIG. 4 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.86, and the step ratio between the second and third fixed forward torque ratios is 1.54.
Description of a Fifth Exemplary Embodiment
[0120] With reference to FIG. 5 a , a powertrain 410 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission, designated generally by the numeral 414 . The transmission 414 is designed to receive at least a portion of its driving power from the engine 12 .
[0121] As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 414 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0122] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 414 . An output member 19 of the transmission 414 is connected to a final drive 16 .
[0123] The transmission 414 utilizes two planetary gear sets 420 and 430 . The planetary gear set 420 employs an outer ring gear member 424 which circumscribes an inner sun gear member 422 . A carrier member 426 rotatably supports a plurality of planet gears 427 such that each planet gear 427 meshingly engages both the outer ring gear member 424 and the inner sun gear member 422 of the first planetary gear set 420 .
[0124] The planetary gear set 430 also has an outer ring gear member 434 that circumscribes an inner sun gear member 432 . A plurality of planet gears 437 are also rotatably mounted in a carrier member 436 such that each planet gear member 437 simultaneously, and meshingly engages both the outer, ring gear member 434 and the inner, sun gear member 432 of the planetary gear set 430 .
[0125] The transmission input member 17 is continuously connected with the carrier member 426 , and the transmission output member 19 is continuously connected with the carrier member 436 .
[0126] The transmission 414 also incorporates first and second motor/generators 480 and 482 , respectively. The stator of the first motor/generator 480 is secured to the transmission housing 460 . The rotor of the first motor/generator 480 is secured to the ring gear member 434 .
[0127] The stator of the second motor/generator 482 is also secured to the transmission housing 460 . The rotor of the second motor/generator 482 is secured to the sun gear member 432 .
[0128] A first torque-transfer device, such as a clutch 450 , selectively connects the carrier member 426 with the ring gear member 434 . A second torque-transfer device, such as clutch 452 , selectively connects the ring gear member 424 with the sun gear member 432 . A third torque-transfer device, such as brake 454 , selectively connects the sun gear member 422 with the transmission housing 460 . A fourth torque transfer device, such as the brake 455 , is connected in parallel with the motor/generator 480 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 457 , is connected in parallel with the motor/generator 482 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque-transfer devices 450 , 452 , 454 , 455 and 457 are employed to assist in the selection of the operational modes of the transmission 414 . The hybrid transmission 414 receives power from the engine 12 and also from an electric power source 486 , which is operably connected to a controller 488 .
[0129] The operating mode table of FIG. 5 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 414 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 , F 3 ) as described previously.
[0130] As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 5 b . FIG. 5 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 5 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 420 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 430 . Also, the chart of FIG. 5 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.86, and the step ratio between the second and third fixed forward torque ratios is 1.54.
Description of a Sixth Exemplary Embodiment
[0131] With reference to FIG. 6 a , a powertrain 510 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transrission, designated generally by the numeral 514 . The transmission 514 is designed to receive at least a portion of its driving power from the engine 12 .
[0132] As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 514 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0133] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 514 . An output member 19 of the transmission 514 is connected to a final drive 16 .
[0134] The transmission 514 utilizes two planetary gear sets 520 and 530 . The planetary gear set 520 employs an outer ring gear member 524 which circumscribes an inner sun gear member 522 . A carrier member 526 rotatably supports a plurality of planet gears 527 such that each planet gear 527 meshingly engages both the outer ring gear member 524 and the inner sun gear member 522 of the first planetary gear set 520 .
[0135] The planetary gear set 530 also has an outer ring gear member 534 that circumscribes an inner sun gear member 532 . A plurality of planet gears 537 are also rotatably mounted in a carrier member 536 such that each planet gear member 537 simultaneously, and meshingly engages both the outer, ring gear member 534 and the inner, sun gear member 532 of the planetary gear set 530 .
[0136] The transmission input member 17 is continuously connected with the carrier member 526 , and the transmission output member 19 is continuously connected with the carrier member 536 .
[0137] The transmission 514 also incorporates first and second motor/generators 580 and 582 , respectively. The stator of the first motor/generator 580 is secured to the transmission housing 560 . The rotor of the first motor/generator 580 is secured to the ring gear member 534 .
[0138] The stator of the second motor/generator 582 is also secured to the transmission housing 560 . The rotor of the second motor/generator 582 is secured to the sun gear member 532 .
[0139] A first torque-transfer device, such as a clutch 550 , selectively connects the carrier member 526 with the ring gear member 534 . A second torque-transfer device, such as a clutch 552 , selectively connects the ring gear member 524 with the sun gear member 532 . A third torque-transfer device, such as a brake 554 , selectively connects the sun gear member 522 with the transmission housing 560 . A fourth torque transfer device, such as the brake 555 , is connected in parallel with the motor/generator 580 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 557 , is connected in parallel with the motor/generator 582 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque-transfer devices 550 , 552 , 554 , 555 and 557 are employed to assist in the selection of the operational modes of the hybrid transmission 514 .
[0140] The hybrid transmission 514 receives power from the engine 12 , and also exchanges power with an electric power source 586 , which is operably connected to a controller 588 .
[0141] The operating mode table of FIG. 6 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 514 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 , F 3 ) as described previously.
[0142] As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 6 b . FIG. 6 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 6 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 520 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 530 . Also, the chart of FIG. 4 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.86, and the step ratio between the second and third fixed forward torque ratios is 1.54.
Description of a Seventh Exemplary Embodiment
[0143] With reference to FIG. 7 a , a powertrain 610 is shown, including an engine 12 connected to one preferred embodiment of the improved electrically variable transmission, designated generally by the numeral 614 . The transmission 614 is designed to receive at least a portion of its driving power from the engine 12 .
[0144] As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 614 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0145] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connected to a planetary gear set in the transmission 614 . An output member 19 of the transmission 614 is connected to a final drive 16 .
[0146] The transmission 614 utilizes two planetary gear sets 620 and 630 . The planetary gear set 620 employs an outer ring gear member 624 which circumscribes an inner sun gear member 622 . A carrier member 626 rotatably supports a plurality of planet gears 627 such that each planet gear 627 meshingly engages both the outer ring gear member 624 and the inner sun gear member 622 of the first planetary gear set 620 .
[0147] The planetary gear set 630 also has an outer ring gear member 634 that circumscribes an inner sun gear member 632 . A plurality of planet gears 637 are also rotatably mounted in a carrier member 636 such that each planet gear member 637 simultaneously, and meshingly engages both the outer, ring gear member 634 and the inner, sun gear member 632 of the planetary gear set 630 .
[0148] The transmission input member 17 is connected with the carrier member 626 of the planetary gear set 620 , and the transmission output member 19 is connected with the carrier member 636 of the planetary gear set 630 .
[0149] The transmission 614 also incorporates first and second motor/generators 680 and 682 , respectively. The stator of the first motor/generator 680 is secured to the transmission housing 660 . The rotor of the first motor/generator 680 is secured to the sun gear member 622 of the planetary gear set 620 . The stator of the second motor/generator 682 is also secured to the transmission housing 660 . The rotor of the second motor/generator 682 is secured to the sun gear member 632 of the planetary gear set 630 .
[0150] A first torque-transfer device, such as the clutch 650 , selectively connects the carrier member 626 with the ring gear member 634 . A second torque-transfer device, such as the clutch 652 , selectively connects the ring gear member 624 with the sun gear member 632 . A third torque-transfer device, such as brake 654 , selectively connects the ring gear member 634 with the transmission housing 660 . A fourth torque transfer device, such as the brake 655 , is connected in parallel with the motor/generator 680 for selectively braking rotation thereof. A fifth torque transfer device, such as the brake 657 , is connected in parallel with the motor/generator 682 for selectively braking rotation thereof. The first, second, third, fourth and fifth torque-transfer devices 650 , 652 , 654 , 655 and 657 are employed to assist in the selection of the operational modes of the transmission 614 .
[0151] The hybrid transmission 614 receives power from the engine 12 , and also exchanges power with an electric power source 686 , which is operably connected to a controller 688 .
[0152] The operating mode table of FIG. 7 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 614 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 , F 3 ) as described previously.
[0153] As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 7 b . FIG. 7 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 7 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 620 ; and the N R2 /N S2 value is the tooth ratio of the planetary gear set 630 . Also, the chart of FIG. 7 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.86, and the step ratio between the second and third fixed forward torque ratios is 1.54.
Description of an Eighth Exemplary Embodiment
[0154] With reference to FIG. 8 a , a powertrain 710 is shown, including an engine 12 connected to the improved electrically variable transmission (EVT), designated generally by the numeral 714 . Transmission 714 is designed to receive at least a portion of its driving power from the engine 12 . As shown, the engine 12 has an output shaft that serves as the input member 17 of the transmission 714 . A transient torque damper (not shown) may also be implemented between the engine 12 and the input member 17 of the transmission.
[0155] In the embodiment depicted the engine 12 may be a fossil fuel engine, such as a diesel engine which is readily adapted to provide its available power output typically delivered at a constant number of revolutions per minute (RPM).
[0156] Irrespective of the means by which the engine 12 is connected to the transmission input member 17 , the transmission input member 17 is operatively connectable to planetary gear members in the transmission 714 .
[0157] An output member 19 of the transmission 714 is connected to a final drive 16 .
[0158] The transmission 714 utilizes two differential gear sets, preferably in the nature of planetary gear sets 720 and 730 . The planetary gear set 720 employs an outer gear member 724 , typically designated as the ring gear. The ring gear 724 circumscribes an inner gear member 722 , typically designated as the sun gear. A carrier member 726 rotatably supports a plurality of planet gears 727 such that each planet gear 727 meshingly engages both the inner, sun gear member 722 , and the ring gear member 724 .
[0159] The planetary gear set 730 also has an outer gear member 734 , often also designated as the ring gear, that circumscribes an inner gear member 732 , also often designated as the sun gear. A plurality of planet gears 737 , 738 are also rotatably mounted in a carrier member 736 such that each planet gear member 737 meshingly engages the sun gear member 732 , each planet gear 738 engages the outer, ring gear member 734 and the respective planet gear 737 .
[0160] The input member 17 is secured to the carrier member 726 of the planetary gear set 720 . The output member 19 is continuously connected with the ring gear member 734 of the planetary gear set 730 .
[0161] This embodiment 710 also incorporates first and second motor/generators 780 and 782 , respectively. The stator of the first motor/generator 780 is secured to the transmission housing 760 . The rotor of the first motor/generator 780 is connected to the sun gear member 722 through offset gearing 790 .
[0162] The stator of the second motor/generator 782 is also secured to the transmission housing 760 . The rotor of the second motor/generator 782 is selectively alternately connectable to the carrier 736 or sun gear member 732 via the dog clutch 792 alternating between positions “A” and “B.” The rotor of the second motor/generator 782 is connected to the dog clutch 792 through offset gearing 794 .
[0163] A first torque transfer device, such as clutch 750 , selectively connects the carrier member 726 with the carrier member 736 . A second torque transfer device, such as clutch 752 , selectively connects the ring gear member 724 with the sun gear member 732 . A third torque transfer device, such as brake 755 , selectively brakes the rotor of the motor/generator 780 . A fourth torque transfer device, such as brake 757 , selectively brakes the rotor of the motor/generator 782 . The first, second, third and fourth torque transfer devices 750 , 752 , 755 and 757 and dog clutch 792 are employed to assist in the selection of the operational modes of the hybrid transmission 714 .
[0164] The hybrid transmission 714 receives power from the engine 12 , and also exchanges power with an electric power source 786 , which is operably connected to a controller 788 .
[0165] The operating mode table of FIG. 8 b illustrates the clutching engagements, motor/generator conditions and output/input ratios for the five operating modes of the transmission 714 . These modes include the “battery reverse mode” (Batt Rev), the “EVT reverse mode” (EVT Rev), “reverse and forward launch modes” (TC Rev and TC For), “continuously variable transmission range modes” (Range 1 . 1 , 1 . 2 , 1 . 3 . . . ) and “fixed ratio modes” (F 1 , F 2 and F 3 ) as described previously.
[0166] As set forth above, the engagement schedule for the torque-transfer devices is shown in the operating mode table and fixed ratio mode table of FIG. 8 b . FIG. 8 b also provides an example of torque ratios that are available utilizing the ring gear/sun gear tooth ratios given by way of example in FIG. 8 b . The N R1 /N S1 value is the tooth ratio of the planetary gear set 720 and the N R2 /N S2 value is the tooth ratio of the planetary gear set 730 . Also, the chart of FIG. 8 b describes the ratio steps that are attained utilizing the sample of tooth ratios given. For example, the step ratio between first and second fixed forward torque ratios is 1.49.
[0167] In the claims, the language “continuously connected” or “continuously connecting” refers to a direct connection or a proportionally geared connection, such as gearing to an offset axis. Also, the “stationary member” or “ground” may include the transmission housing (case) or any other non-rotating component or components. Also, when a torque transmitting mechanism is said to connect something to a member of a gear set, it may also be connected to an interconnecting member which connects it with that member.
[0168] While various preferred embodiments of the present invention are disclosed, it is to be understood that the concepts of the present invention are susceptible to numerous changes apparent to one skilled in the art. Therefore, the scope of the present invention is not to be limited to the details shown and described but is intended to include all variations and modifications which come within the scope of the appended claims. | The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first and second differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, and five selectable torque-transfer devices (two clutches and three brakes). The selectable torque transfer devices are engaged singly or in combinations of two or three to yield an EVT with a continuously variable range of speeds (including reverse) and up to three mechanically fixed forward speed ratios. The torque transfer devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to plumbing installations, and more particularly, to dual flush systems used in gravity flush toilets and pertains particularly to an improved flush control apparatus.
For many decades household toilets have used a generally rectangular porcelain tank mounted immediately above a porcelain bowl from which about three and one-half to eight gallons of water are rapidly drained in order to flush the waste from the bowl into the sewer system. One very common design uses a flapper valve made of an elastomeric material that normally covers the drain outlet from the tank. When the flush handle on the outside of the tank is manually depressed the flapper valve is lifted and the head of water in the tank drains through the drain outlet into the bowl. The flapper valve is designed with an inverted air chamber so that it initially floats as it is lifted away from the drain outlet in the bottom of the tank. This allows sufficient flushing water to flow into the bowl even if the user immediately releases the flush handle.
A ballcock valve or toilet tank fill valve mounted in the tank is connected to a pressurized water line in the house. When the tank drains, a float ball connected to the ballcock valve descends. This turns the ballcock valve ON and it begins to refill the tank with water at a rate much slower than the rate at which water flows through the drain outlet. When the tank is nearly empty, the flapper valve closes. The tank continues to refill as the float ball connected to the ballcock rises. At the same time water from the ballcock valve enters an overflow tube and refills the bowl to the normal standing water level to provide a trap seal. Once the float ball reaches a predetermined height indicating that the tank is full, the ballcock valve completely turns OFF.
The foregoing conventional household toilet is wasteful and inefficient since a relatively large quantity of water is used to accomplish each flush. This is because the limited elevation of the tank provides only a modest water pressure head. The pressure head is obtained from the potential energy stored in the tank. As the body of water flows through the drain outlet of the tank it starts the siphoning action in the bowl and flushes the standing water in the bowl along with its waste contents into the sewer line.
Fresh water is becoming an increasingly valuable natural resource. Many geographic regions of the United States, such as Southern California, have experienced prolonged periods of drought. Arid parts of the country often take water from remote locations whose environments suffer as a result. For example, Los Angeles diverts large amounts of water from Mono Lake which has shrunk significantly since the 1930's. Furthermore, the more water that is flushed down toilets, the more volume of sewage there is that must be treated. Sewage delivery systems and treatment plants are expensive to construct and maintain. Treatment plants require large amounts of land and have offensive odors. Residents near any proposed sewage treatment site will often object vehemently.
According to a Dec. 19, 1980 report by the U. S Environmental Protection Agency (EPA), approximately 40% of the water used in a home is flushed down the toilet. The typical toilet in the U.S. uses between 3.5 and 7 gallons of water per flush. Effective Jan. 1, 1994, Federal law requires the installation of toilets in all new construction that use 1.6 gallons or less of water per flush. There is a critical need to ensure effective flushing in such toilets for sanitation reasons. Also, unless the flushing action in such low water volume toilets can be made efficient, users will flush them twice during each visit to the bathroom to ensure a complete flush, thereby negating the intended water savings.
There is also a critical need to design an apparatus to retrofit existing 3.5, 5 and 7 gallon toilets to lessen the amount of water used during each flush while maintaining an effective flush. Various approaches have been heretofore employed in regions subject to water rationing to reduce water consumption by conventional toilets. These have included lowering the tank level or introducing a brick or dam to decrease the water volume released during each flush. However, these approaches have generally been unsatisfactory because the consequent reduction in water flow into the bowl often results in incomplete flushing. Users then flush twice, compounding the waste of water.
Water shortages throughout the major portions of the United States have forced major water conservation efforts. These efforts have led to improvements in the toilet, such that as little as 1.6 gallons of water is utilized for a standard flush for solid waste removal.
Even further efforts at conservation have led to proposals for a dual flushing system, wherein a short flush is utilized to flush liquid wastes, and a long flush is utilized to flush solid wastes. The water is dispensed to the toilet bowl by way of a flush valve and seat, such as a flapper valve which allows the user to flush all or most of the tank water for a long flush, or just a portion of the tank water on the short flush. The flapper valve must be controlled to close prior to emptying the tank for the short flush. Once the toilet has been flushed, the tank is refilled automatically by a refill valve assembly connected to a water supply.
The typical flush valve assembly comprises a flapper valve having a normally downward opening air chamber which acts as a float when the flapper is raised off its seat to hold the flapper valve open when water is in the tank. This orients the air opening generally outwardly so that when the tank empties, the flapper follows the water level down to the point where the bulb and/or flange of the flapper are drawn into the flow stream which pulls the flapper down to seat, closing the flush valve. The refill mechanism is activated to refill the bowl and the tank.
Many different approaches to providing a dual flush system have been proposed. A major drawback to most of these is that they are complicated and expensive. Another drawback of many of them is that they do not function satisfactorily. One problem is that they do not account for the fact that successive short flushes typically will result in a bowl having less and less water, eventually not sealing the p-trap adequately. This invariably results in poor flush performance and failure to clear the bowl completely. It also results in wasting water by requiring double flushing to completely remove bowl contents when the trap is not fill at the start of the flush cycle.
Accordingly, it is desirable that an improved dual flush apparatus be available which is simple and effective, adequately providing for both long flushes and short flushes of a toilet, with maximum efficiency for the volume of water used.
SUMMARY OF THE INVENTION
It is the primary object of the present invention to provide an improved flush apparatus for effectively providing both long flushes and short flushes of a toilet, so as to more efficiently handle both solid and liquid waste with minimum water consumption.
To achieve this objective, a control system has been provided to evacuate air from a flapper at two different rates with a unique use of mechanical time delays.
In accordance with a primary aspect of the invention, multiple volume flush control apparatus for controlling a flush valve in a bottom of a flush tank, comprises a flush valve having a ventable buoyancy air chamber, a vent control assembly having a venting chamber communicating with said air chamber, first valve means for selectively activating said venting chamber for venting said air chamber at first rate, and second valve means for selectively activating said venting chamber for venting said air chamber at a second rate.
BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENTS
The above and other objects and advantages of the present invention will be apparent from the following description when read in conjunction with the accompanying drawings wherein:
FIG. 1 is a top plan view in section of a dual flush apparatus in accordance with a preferred embodiment of the invention; and
FIG. 2 is an elevation view in section of the actuated assembly of the embodiment of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, particularly FIG. 1, there is illustrated a refill control apparatus in accordance with the preferred embodiment of the invention designated generally by the numeral 10.
Referring to FIG. 1 of the drawings, a dual-flush apparatus in accordance with the invention is illustrated and designated generally by the numeral 10. The apparatus is adapted to mount in the usual flush lever mounting opening in a typical flush tank of a typical toilet. The apparatus comprises a generally cylindrical housing 12 forming a cylinder with cylindrical walls 14 defining a cylinder chamber in which is reciprocally mounted a piston 16. The housing 12 includes a coaxial tubular extension 18 in which a coaxially extending shaft 20 of piston 16 is mounted. An 0-ring 22 seals the piston 16 in the cylindrical housing 14. An O-ring 24 seals the shaft 20 in the extension 18 of the housing. Diaphragm or bellow-type seals may be utilized in place of the O-rings to reduce frictional forces, if desirable.
The piston 16 divides the cylindrical vacuum or venting chamber into a chamber 26 and a control chamber 28. The chamber 26 communicates by means of a port 30 with a line or tube 32 which communicates with and vents a flapper valve 34 mounted in a flush tank.
An oscillating shaft 36 is mounted in the tubular extension 18 of the housing and includes a cam and follower arrangement, including a follower pin 38 engagable with a spiral cam 40 formed in the tubular extension 18. An arm or lever 42 is mounted on the outer end of the shaft 36 and is connected by a suitable chain or other link 44 to the valve 34 for lifting the valve from its seat. Reciprocation of the piston 16 causes rotation of the shaft or oscillation of the shaft 36 so that in its fully extended position, as shown in FIG. 1, the arm 42 lifts the valve 34 from its seat thereby flushing the commode.
The housing 12 includes a cover or closure 46 which contains a cylindrical extension member 48 substantially coaxial thereof which defines a valve housing. The valve housing 48 is sized to extend into and mount in a bore 50 of a flush tank wall 52. This bore is typically the mounting hole for the flush lever of a traditional flush tank.
A check valve 54 vents the chamber 28 as the piston is moved in a right-hand direction as illustrated in FIG. 1. A spring 56 biases the piston 16 normally in a left-hand direction, as viewed in FIG. 1. The piston 16 is formed with a centrally disposed flat portion of 58 disposed for engagement by means first and second valve means comprising a pair of actuating and control valves 60 and 62 respectively.
The actuator valves 60 and 62 comprise elongated stems which are mounted in cylindrical bores 64 and 66 formed in the housing extension or valve housing 48. The valve stem 60 is provided with a pair of valve slots or ports 68 positioned so that they are exposed to and vent the chamber 28 when the valve stem is pushed to its far right position, as illustrated in FIG. 1. Similarly, the valve stem 62 is provided with a pair of vent slots or ports 70 which are similarly exposed to the chamber 28 and are effective to vent the chamber when communicated therewith. The vent slots 68 and 70 will have different size and venting capacities so that they vent the chamber at different selective rates. One valve will provide for a slow return of the piston 16 and a long flush. The other valve will provide for a quicker return of the piston 16 and a short flush.
A button actuating assembly (FIGS. 1 and 2) includes a housing or frame 72 having a bore 74 mounted on the valve housing extension 48 and retained such as by means of a nut 76. A pair of actuating buttons or levers 78 and 80 are pivotly mounted in the frame 72 and engage the ends of the valves 60 and 62. These levers may be selectively biased inward to bias the piston 16 to the flush position, as illustrated in FIG. 1, wherein the arm 42 is raised to lift the flapper valve 34 from its seat. The flapper or flush valve 34 has the usual buoyancy air chamber that keeps the valve open until the chamber is vented.
In operation, once a valve 60 or 62 is actuated as illustrated in FIG. 1 biasing the piston to the right, the valve 34 is lifted and a flush begins. As the actuating button or lever is released, the valve 60 or 62 is in a position to begin venting chamber 28 allowing the spring 56 to begin forcing piston 16 to the left, as illustrated in FIG. 1. This draws air by vacuum by way of line 32 thereby slowly venting air from the buoyancy chamber of the valve 34. As the valve 60 is pushed toward the left by piston 16, more and more of the air is vented from the chamber 28 thereby drawing a vacuum in chamber 26 and venting the buoyancy chamber of the valve 34 allowing it to close and end the flush.
One valve 60 of the valves 60 and 62 is provided with larger slots than the other two, providing more rapid venting of the chamber 28 and thereby a more rapid venting of the buoyancy chamber of valve 34 for a short flush. The other of the valves is provided with slots which provide a slower venting of the chamber 28 and thereby a slower venting of the buoyancy chamber 34 of the valve 34. Thus, a selected long or short flush is provided.
While we have illustrated and described our invention by means of specific embodiments, it is to be understood that numerous changes and modifications may be made therein without departing from the spirit and the scope of the invention as defined in the appended claims. | A multiple volume flush control apparatus for controlling a flush valve in a bottom of a flush tank, comprises a flush valve having a ventable buoyancy air chamber, a vent control assembly having a venting chamber communicating with the air chamber, a first valve for selectively activating the venting chamber for venting the air chamber at a first rate, and a second valve for selectively activating the venting chamber for venting the air chamber at a second rate. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This U.S. non-provisional patent application is a continuation of U.S. patent application Ser. No. 14/830,299, filed Aug. 19, 2015, which is a continuation of and claims priority from U.S. patent application Ser. No. 14/057,380, filed Oct. 18, 2013, now U.S. Pat. No. 9,136,395, which is a divisional of and claims priority from U.S. patent application Ser. No. 13/220,376, filed Aug. 29, 2011, now U.S. Pat. No. 8,569,827, which claims the benefit of Korean Patent Application 10-2010-0091140, filed Sep. 16, 2010, the entire contents of which are hereby incorporated herein by reference.
BACKGROUND
The present disclosure herein relates to a semiconductor device and a method of fabricating the same and, more particularly, to a three-dimensional (3D) semiconductor memory device and a method of fabricating the same.
Due to characteristics such as miniaturization, multifunction and/or low-fabricating cost, semiconductor devices are getting the spotlight as an important factor in electronic industries. With the advance of electronic industries, requirements for the superior performances and/or low costs of semiconductor devices are increasing. For satisfying such requirements, high-integrating of semiconductor devices is growing. Particularly, high-integrating of semiconductor memory devices storing logical data is growing more.
In a degree of integration of typical Two-Dimensional (2D) semiconductor memory devices, planar areas that unit memory cells occupy may be main factors for deciding the degree of integration. Therefore, a degree of integration of the typical 2D semiconductor memory devices may be largely affected by the level of a technology for forming fine patterns. However, the technology for forming the fine patterns may be gradually reaching limitations, and also, the fabricating costs of semiconductor memory devices may increase because high-cost equipment is required. For solving such limitations, 3D semiconductor memory devices including three dimensionally-arranged memory cells have been proposed.
SUMMARY
Three-dimensional (3D) nonvolatile memory devices according to embodiments of the invention include a substrate having a well region of second conductivity type (e.g., P-type) therein and a common source region of first conductivity type (e.g., N-type) on the well region. A recess is provided in the substrate. In some embodiments of the invention, the recess extends partially through the common source region. A vertical stack of nonvolatile memory cells are provided on the substrate. This vertical stack of nonvolatile memory cells includes a vertical stack of spaced-apart gate electrodes and a vertical active region, which extends on sidewalls of the vertical stack of spaced-apart gate electrodes and on a sidewall of the recess. Gate dielectric layers are provided, which extend between respective ones of the vertical stack of spaced-apart gate electrodes and the vertical active region.
In other embodiments of the invention, the recess extends entirely through the common source region, which forms a P-N rectifying junction with the well region, and a sidewall of the recess defines an interface between the vertical active region and the well region. In addition, each of the gate dielectric layers may include a composite of: (i) a tunnel insulating layer in contact with the vertical active region, (ii) a charge storage layer on the tunnel insulating layer, (iii) a barrier dielectric layer on the charge storage layer; and (iv) a blocking insulating layer extending between the barrier dielectric layer and a respective gate electrode. In some of these embodiments of the invention, the barrier dielectric layer may be formed of a material having a greater bandgap relative to the blocking insulating layer. According to still further embodiments of the invention, a protective dielectric layer is provided on a sidewall of the recess. This protective dielectric layer extends between the vertical active region and the common source region. A bottom of the recess may also define an interface between the vertical active region and the well region. This vertical active region, which may have a cylindrical shape, may include a plurality of concentrically-arranged semiconductor layers of first conductivity type having equivalent or different dopant concentrations therein.
According to additional embodiments of the invention, the vertical stack of spaced-apart gate electrodes has an opening extending therethrough that is aligned to the recess. In addition, the gate dielectric layers may have a cylindrical shape, and may be concentrically-arranged relative to the plurality of concentrically-arranged semiconductor layers.
According to still further embodiments of the invention, the vertical active region includes an active region plug filling the recess and a cylindrically-shaped active layer on the active region plug. The cylindrically-shaped active layer includes a plurality of concentrically-arranged semiconductor layers of first conductivity type having equivalent or different doping concentrations therein. A vertical stack of at least two spaced-apart gate electrodes of respective ground selection transistors may also be provided, which extend opposite the active region plug. These ground selection transistors include respective gate dielectric layers that extend on sidewalls of the active region plug. The gate dielectric layers of the vertical stack of nonvolatile memory cells may be formed of different materials relative to the gate dielectric layers of the stacked ground selection transistors.
Methods of forming three-dimensional (3D) nonvolatile memory devices according to embodiments of the invention may include forming a vertical stack of a plurality of sacrificial layers and a plurality of insulating layers arranged in an alternating sequence, on a substrate. A selective etching step is then performed to etch through the vertical stack to define a first opening therein and a recess in the substrate. The recess is filled with an electrically conductive active region plug, which is electrically connected to a well region in the substrate. A sidewall of the first opening is then lined with a first vertical active layer before the first opening is filled with a dielectric pattern that extends on the first vertical active layer. Another selective etching step is performed to selectively etch through the vertical stack to define a second opening therein that exposes the substrate. Portions of the sacrificial layers extending between each of the plurality of insulating layers in the vertical stack are then replaced with gate dielectric layers and gate electrodes of respective memory cells. The step of lining a sidewall of the first opening may include lining a sidewall of the first opening with a first vertical active layer that contacts an upper surface of the active region plug. The step of filling the recess with an active region plug may also include filling the recess with an active region plug having an upper surface that is elevated relative to surface of the substrate. In particular, the substrate may include a well region of second conductivity type and a common source region of first conductivity type extending between the well region and a surface of the substrate, and the recess containing the active region plug may extend entirely through the common source region.
According to still further embodiments of the invention, the step of lining a sidewall of the first opening with a first vertical active layer may be preceded by a step of lining the sidewall of the first opening with a first electrically insulating sub-layer that contacts an upper surface of the active region plug. A step may also be performed to selectively etching through the first vertical active layer and the first electrically insulating sub-layer in sequence to expose the upper surface of the active region plug. In addition, the step of filling the first opening with a dielectric pattern may be preceded by lining an inner sidewall of the first vertical active layer with a second vertical active layer that contacts the upper surface of the active region plug. These first and second vertical active layers may be formed as doped or undoped cylindrically-shaped silicon layers.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings:
FIG. 1A is a plan view illustrating a three-dimensional (3D) semiconductor memory device according to an embodiment of the inventive concept;
FIG. 1B is a cross-sectional view taken along line □-□′ of FIG. 1A ;
FIG. 1C is a magnified view of a portion A of FIG. 1B ;
FIG. 2A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing a modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 2B is a cross-sectional view taken along line □-□′ of FIG. 1A for describing other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 3A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing still other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 3B is a magnified view of a portion B of FIG. 3A ;
FIG. 3C is a magnified view of a portion B of FIG. 3A for describing even other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 3D is a magnified view of a portion B of FIG. 3A for describing yet other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 4A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing further modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 4B is a magnified view of a portion C of FIG. 4A ;
FIG. 5A is a plan view illustrating still further modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 5B is a cross-sectional view taken along line □-□′ of FIG. 5A ;
FIGS. 6A to 6H are cross-sectional views taken along line □-□′ of FIG. 1A for describing a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept;
FIGS. 7A to 7D are cross-sectional views taken along line □-□′ of FIG. 1A for describing a modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept;
FIGS. 8A to 8F are cross-sectional views taken along line □-□′ of FIG. 1A for describing other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept;
FIGS. 9A to 9D are cross-sectional views taken along line □-□′ of FIG. 1A for describing still other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept;
FIGS. 10A to 10C are cross-sectional views taken along line □-□′ of FIG. 1A for describing even other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept;
FIG. 11 is a cross-sectional view illustrating a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12A is a cross-sectional view illustrating a modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12B is a cross-sectional view illustrating other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12C is a cross-sectional view illustrating still other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12D is a cross-sectional view illustrating even other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12E is a cross-sectional view illustrating yet other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 12F is a cross-sectional view illustrating further modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept;
FIGS. 13A to 13E are cross-sectional views for describing a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 14 is a cross-sectional view illustrating a modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept;
FIGS. 15A to 15F are cross-sectional views illustrating other modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept;
FIGS. 16A and 16B are cross-sectional views illustrating still other modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept;
FIG. 17 is a block diagram schematically illustrating an example of an electronic system including a 3D semiconductor memory device according to an embodiment of the inventive concept; and
FIG. 18 is a block diagram schematically illustrating an example of a memory card including a 3D semiconductor memory device according to an embodiment of the inventive concept.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The present invention now will be described more fully with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout.
It will be understood that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer (and variants thereof), it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer (and variants thereof), there are no intervening elements or layers present. Like reference numerals refer to like elements throughout.
It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.
Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present 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 “comprising”, “including”, having” and variants thereof, when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. In contrast, the term “consisting of” when used in this specification, specifies the stated features, steps, operations, elements, and/or components, and precludes additional features, steps, operations, elements and/or components.
Embodiments of the present invention are described herein with reference to cross-section and perspective illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the present invention. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments of the present invention should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a sharp angle may be somewhat rounded due to manufacturing techniques/tolerances.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
FIG. 1A is a plan view illustrating a 3D semiconductor memory device according to an embodiment of the inventive concept. FIG. 1B is a cross-sectional view taken along line □-□′ of FIG. 1A . FIG. 1C is a magnified view of a portion A of FIG. 1B . Referring to FIGS. 1A and 1B , a well region 102 doped with a first conductive dopant may be disposed in a semiconductor substrate 100 (hereinafter referred to as a substrate). The substrate 100 may be a silicon substrate, a germanium substrate or a silicon-germanium substrate, for example a common source region 105 doped with a second conductive dopant may be formed in the well region 102 . An upper surface of the common source region 105 may be disposed on the substantially same level as that of the upper surface of the substrate 100 . A lower surface of the common source region 105 may be disposed on a level higher than that of a lower surface of the well region 102 . One of the first and second conductive dopants may be an n-type dopant, and the other may be a p-type dopant. For example, the well region 102 may be doped with a p-type dopant, and the common source region 105 may be doped with an n-type dopant.
A stack-structure, including insulation patterns 110 a and gate patterns 155 L, 155 a 1 , 155 a and 155 U that are stacked alternately and repeatedly, may be disposed on the common source region 105 . A plurality of the stack-structures may be disposed on the common source region 105 . As illustrated in FIG. 1A , the stack-structures may be extended side by side in a first direction. The stack-structures may be spaced apart in a second direction perpendicular to the first direction. The first and second directions may be parallel with the upper surface of the substrate 100 .
A vertical active pattern 130 may pass through the stack-structure. The vertical active pattern 130 may be extended into a recess region 120 that is formed in the common source region 105 under the vertical active pattern 130 . Therefore, the vertical active pattern 130 may be connected to the well region 102 under the vertical active pattern 130 . As illustrated in FIG. 1B , the recess region 120 may vertically pass through the common source region 105 . A bottom surface of the recess region 120 may be disposed on a level lower than that of the lower surface of the common source region 105 . The vertical active pattern 130 may contact the bottom surface of the recess region 120 . Accordingly, the vertical active pattern 130 may contact the well region 102 . Also, the vertical active pattern 130 may contact a sidewall of the recess region 120 . As a result, the vertical active pattern 130 may directly contact the common source region 105 .
According to an embodiment of the inventive concept, a portion 122 of the well region 102 just under the bottom surface of the recess region 120 may have a high dopant concentration. In other words, the first conductive dopant concentration of the portion 122 of the well region 102 may be higher than the first conductive dopant concentration of another portion of the well region 102 .
According to an embodiment of the inventive concept, the vertical active pattern 130 may have a hollow pipe shape or a macaroni shape. Herein, the lower end of the vertical active pattern 130 may be in a closed state. The inside of the vertical active pattern 130 may be filled with a filling dielectric pattern 132 .
A gate dielectric layer 150 may be disposed between a sidewall of the vertical active pattern 130 and each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. According to an embodiment of the inventive concept, as illustrated in FIG. 1B , the gate dielectric layer 150 may be extended to cover an upper surface and a lower surface of each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. That is, the extended portion of the gate dielectric layer 150 may be disposed between each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U and the insulation pattern 110 a adjacent to each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U.
The gate dielectric layer 150 will be described below in more detail with reference to FIG. 1C . Referring to FIG. 1C , according to an embodiment of the inventive concept, the gate dielectric layer 150 may include a tunnel dielectric layer 141 , a charge storage layer 142 and a blocking dielectric layer 143 . The tunnel dielectric layer 141 may be adjacent to the sidewall of the vertical active pattern 130 , and the blocking dielectric layer 143 may be adjacent to each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. The charge storage layer 142 may be disposed between the tunnel dielectric layer 141 and the blocking dielectric layer 143 . According to an embodiment of the inventive concept, as illustrated in FIG. 1C , the entirety of the gate dielectric layer 150 (i.e., the tunnel dielectric layer 141 , the charge storage layer 142 and the blocking dielectric layer 143 ) may be extended to cover the upper and lower surfaces of each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U.
The tunnel dielectric layer 141 may include oxide and/or oxynitride. The tunnel dielectric layer 141 may be single-layered or multi-layered. The charge storage layer 142 may include a dielectric material having traps for storing electric charges, for example, the charge storage layer 142 may include nitride and/or metal-oxide. The blocking dielectric layer 143 may include a high-k dielectric layer having a dielectric constant higher than that of the tunnel dielectric layer 141 . For example, the high-k dielectric layer in the blocking dielectric layer 143 may include metal-oxide such as aluminum-oxide or hafnium-oxide. Furthermore, the blocking dielectric layer 143 may further include a barrier dielectric layer. The barrier dielectric layer in the blocking dielectric layer 143 may include a dielectric material having a greater band gap than the high-k dielectric layer in the blocking dielectric layer 143 . For example, the barrier dielectric layer may include oxide. The barrier dielectric layer may be disposed between the high-k dielectric layer and the charge storage layer 142 .
A lowermost gate pattern 155 L in the stack-structure may correspond to a ground selection gate. A ground selection transistor including the lowermost gate pattern 155 L may include a vertical channel region that is defined in the sidewall of the vertical active pattern 130 . As illustrated in FIGS. 1A and 1B , the entire lower surface of the lowermost gate pattern 155 L may substantially overlap with the common source region 105 .
An uppermost gate pattern 155 U in the stack-structure may correspond to a string selection gate. Gate patterns 155 a 1 and 155 a between the uppermost gate pattern 155 U and the lowermost gate pattern 155 L may correspond to cell gates. A string selection transistor including the uppermost gate pattern 155 U and cell transistors including the cell gates may also include vertical channel regions that are defined in the sidewall of the vertical active pattern 130 a . The vertical channel regions of the ground selection transistor, the cell transistor and the string selection transistor configuring one cell string may be defined in the vertical active pattern 130 .
According to an embodiment of the inventive concept, among gate patterns used as the cell gates in the stack-structure, a gate pattern most adjacent to the lowermost gate pattern 155 L may correspond to a dummy cell gate. For example, the gate pattern 1551 a disposed just on the lowermost gate pattern 155 L may be a dummy gate pattern. For example, the gate pattern 155 a 1 that is stacked secondly from the substrate 100 may be a dummy cell gate. Naturally, one of the insulation pattern 110 a is disposed between the lowermost gate pattern 155 L and the secondly-stacked gate pattern 155 a 1 . For example, a dummy cell transistor including the secondly-stacked gate pattern 155 a 1 may have the same shape as that of a cell transistor storing data, but may not serve as the cell transistor. For example, the dummy cell transistor may perform only a turn-on/off function. Thus, the secondly-stacked gate pattern 155 a 1 may be a second ground selection gate. In this case, the cell string may include a plurality of stacked ground selection transistors.
A plurality of the vertical active patterns 130 may pass through each of the stack-structures. As illustrated in FIG. 1A , the vertical active patterns 130 passing though each of the stack-structures may be arranged in the first direction to form one column. Alternatively, the vertical active patterns 130 passing though each of the stack-structures may be arranged in a zigzag shape in the first direction.
The vertical active pattern 130 may include a semiconductor material. For example, the vertical active pattern 130 may include the same semiconductor material as that of the substrate 100 . The vertical active pattern 130 may have an undoped state, or may be doped with the first conductive dopant. The vertical active pattern 130 may have a poly-crystalline state or a single crystalline state. The gate patterns 155 L, 155 a 1 , 155 a and 155 U include a conductive material. For example, the gate patterns 155 L, 155 a 1 , 155 a and 155 U may include at least one of a doped semiconductor (for example, doped silicon and others), a metal (for example, tungsten, aluminum, copper and others), a transition metal (for example, titanium, tantalum and others) or a conductive metal nitride (for example, a titanium nitride, a tantalum nitride and others). The insulation patterns 110 a may include oxide.
A device isolation pattern 160 a may be disposed between the stack-structures. An upper surface of the device isolation pattern 160 a and an upper surface of the stack-structure may substantially be coplanar. An interlayer dielectric 165 may be disposed on the substrate 100 . A contact plug 167 may be connected to an upper end of the vertical active pattern 130 through the interlayer dielectric 165 . A drain being doped with the second conductive dopant may be formed in the upper portion of the vertical active pattern 130 . A lower surface of the drain may be disposed on a level adjacent to an upper surface of the uppermost gate pattern 155 U. A bit line 170 may be disposed on the interlayer dielectric 165 , and may be connected to the contact plug 167 . The bit line 170 may be extended in the second direction and cross over the stack-structure. The interlayer dielectric 165 may include oxide. The contact plug 167 includes a conductive material. For example, the contact plug 167 may include tungsten. The bit line 170 also includes a conductive material. As an example, the bit line 170 may include tungsten, copper, aluminum or the like.
According to the above-described 3D semiconductor memory device, the vertical active pattern 130 may be disposed in the recess region 120 passing though the common source region 105 and be connected to the well region 102 . Moreover, the common source region 105 may be disposed under the lowermost gate pattern 155 L. Therefore, a distance between the vertical active pattern 130 and the common source region can be minimized, and also the vertical active pattern 130 can be connected to the well region 102 . Consequently, a current flowing through the vertical active pattern 130 can quickly flow to the common source region 105 . Accordingly, the reduction of an amount of current in a cell transistor can be minimized. Also, the vertical active pattern 130 is connected to the well region 102 , such that the erasing operation of cell transistors is very easy. As a result, the 3D semiconductor memory device can be implemented which has excellent reliability and is optimized for high integration.
Next, the modification examples of the 3D semiconductor memory device according to an embodiment of the inventive concept will be described below with reference to the accompanying drawings. In the modification examples, a description on the same elements as the above-described elements will be omitted for avoiding a repetitive description.
FIG. 2A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing a modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 2A and according to the modification example, protection dielectric patterns 173 a may be disposed between the insulation patterns 110 a and the vertical active pattern 130 and between the inner sidewall of the recess region 120 and the vertical active pattern 130 . The protection dielectric pattern 173 a may include a dielectric material for protecting the vertical active pattern 130 in a fabricating process. For example, the protection dielectric pattern 173 a may include oxide. According to the modification example, a capping semiconductor pattern 175 may be disposed on the vertical active pattern 130 . The capping semiconductor pattern 175 may also be disposed on the protection dielectric pattern 173 a that is disposed between an uppermost insulation pattern 110 a and the vertical active pattern 130 . The upper end of the vertical active pattern 130 may be disposed on a level lower than an upper surface of the uppermost insulation pattern 110 a . The upper surface of the capping semiconductor pattern 175 and the upper surface of the uppermost insulation pattern 110 a may be substantially coplanar. The capping semiconductor pattern 175 may include the same semiconductor material as that of the vertical active pattern 130 . The capping semiconductor pattern 175 may be doped with the second conductive dopant. The contact plug 167 may be connected to the capping semiconductor pattern 175 .
FIG. 2B is a cross-sectional view taken along line □-□′ of FIG. 1A for describing other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 2B and according to the modification example, a bottom surface of the recess region 120 may be disposed on a level higher than the lower surface of the common source region 105 . In this case, a region 122 a being counter-doped with the first conductive dopant may be disposed under the bottom surface of the recess region 120 a . The counter-doped region 122 a may contact the vertical active pattern 130 and the well region 102 . Therefore, the vertical active pattern 130 may be connected to the well region 102 through the counter-doped region 122 a.
FIG. 3A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing still other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. FIG. 3B is a magnified view of a portion B of FIG. 3A . Referring to FIG. 3A , a gate dielectric layer 150 a according to the modification example may be disposed between a vertical active pattern 130 a and each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. The gate dielectric layer 150 a may include a first sub-layer 147 and a second sub-layer 149 . The first sub-layer 147 may be substantially extended vertically and be disposed between the vertical active pattern 130 a and the insulation pattern 110 a . The second sub-layer 149 may be substantially extended horizontally and cover the lower surface and upper surface of each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. The gate dielectric layer 150 a may include the tunnel dielectric layer, the charge storage layer and the blocking dielectric layer. Herein, the first sub-layer 147 may include at least a portion of the tunnel dielectric layer, and the second sub-layer 149 may include at least a portion of the blocking dielectric layer. One of the first and second sub-layers 147 and 149 may include the charge storage layer. In other words, a portion of the gate dielectric layer 150 a including the tunnel dielectric layer, the charge storage layer and the blocking dielectric layer may be extended vertically, and another portion of the gate dielectric layer 150 a may be extended horizontally.
The vertical active pattern 130 a may include first and second semiconductor patterns 123 and 124 . The first semiconductor pattern 123 may be disposed between the second semiconductor pattern 124 and the first sub-layer 147 . The first semiconductor pattern 123 may contact the first sub-layer 147 . According to an embodiment of the inventive concept, the first semiconductor pattern 123 may have a macaroni shape or a pipe shape where an upper end and a lower end are opened. The first semiconductor pattern 123 may not contact the inner surface of the recess region 120 by the first sub-layer 147 . The second semiconductor pattern 124 may contact the first semiconductor pattern 123 and the inner surface of the recess region 120 . The second semiconductor pattern 124 may have a macaroni shape or a pipe shape where a lower end is closed. A filling dielectric pattern 132 may fill the inside of the second semiconductor pattern 124 . The first and second semiconductor patterns 123 and 124 may have an undoped state or be doped with a dopant (i.e., the first conductive dopant) having the same type as that of the well region 102 .
According to an embodiment of the inventive concept, as illustrated in FIG. 3B , the first sub-layer 147 of the gate dielectric layer 150 a may include a tunnel dielectric layer 141 , a charge storage layer 142 and a barrier dielectric layer 144 . In this case, the second sub-layer 149 may include a high-k dielectric material (for example, metal-oxide such as aluminum oxide or hafnium oxide) having a dielectric constant higher than that of the tunnel dielectric layer 141 . The barrier dielectric layer 144 may include a dielectric material having a greater band gap than that of the high-k dielectric material. For example, the barrier dielectric layer 144 may include oxide. The second sub-layer 149 and the barrier dielectric layer 144 , disposed between the charge storage layer 142 and each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U, may included in the blocking dielectric layer. In other words, the first sub-layer 147 may include the tunnel dielectric layer 141 , the charge storage layer 142 and a portion (i.e., the barrier dielectric layer 144 ) of the blocking dielectric layer, and the second sub-layer 149 may include another portion (i.e., the high-k dielectric layer) of the blocking dielectric layer. However, an embodiment of the inventive concept is not limited thereto. The first and second sub-layers of the gate dielectric layer may be combined differently.
FIG. 3C is a magnified view of a portion B of FIG. 3A for describing even other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 3C , a first sub-layer 147 a of a gate dielectric layer 150 b according to the modification example may include a tunnel dielectric layer 141 and a charge storage layer 142 , and a second sub-layer 149 a of the gate dielectric layer 150 b may include a barrier dielectric layer 144 and a high-k dielectric layer 146 . The high-k dielectric layer 146 may be formed of the same material as the high-k dielectric material that has been described above with reference to FIG. 3B . According to the modification example, the second sub-layer 149 b may correspond to a blocking dielectric layer. According to the modification example, the first sub-layer 147 a may include the tunnel dielectric layer 141 and the charge storage layer 142 , and the second sub-layer 149 a may include the blocking dielectric layer.
FIG. 3D is a magnified view of a portion B of FIG. 3A for describing yet other modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 3D , a first sub-layer 147 b of a gate dielectric layer 150 c according to the modification example may include the tunnel dielectric layer, and a second sub-layer 149 b of the gate dielectric layer 150 c may include the charge storage layer 142 and the blocking dielectric layer 143 . According to the modification example, the tunnel dielectric layer in the gate dielectric layer 150 c may be extended vertically and be disposed between the vertical active pattern 130 a and the insulation pattern 110 a , and the charge storage layer 142 and the blocking dielectric layer 143 in the gate dielectric layer 150 c may be extended horizontally and cover the upper surface and lower surface of each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U.
The first and second sub-layers according to an embodiment of the inventive concept are not limited to the modification examples that have been described above with reference to FIGS. 3B, 3C and 3D . The first and second sub-layers may be combined differently.
FIG. 4A is a cross-sectional view taken along line □-□′ of FIG. 1A for describing further modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. FIG. 4B is a magnified view of a portion C of FIG. 4A . Referring to FIGS. 4A and 4B , the entirety of a gate dielectric layer 150 d between the vertical active pattern 130 a and each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U may be substantially extended vertically. That is, the tunnel dielectric layer 141 , charge storage layer 142 and blocking dielectric layer 143 of the gate dielectric layer 150 d may be substantially extended vertically. An extended portion of the gate dielectric layer 150 d may be disposed between the vertical active pattern 130 a and the insulation pattern 110 a . The stack-structure of FIGS. 1A and 1B may have a line shape that is extended in the first direction. Unlike this, the stack-structure may include gate patterns having a flat plate shape. This will be described below with reference to the accompanying drawings.
FIG. 5A is a plan view illustrating still further modification example of a 3D semiconductor memory device according to an embodiment of the inventive concept. FIG. 5B is a cross-sectional view taken along line □-□′ of FIG. 5A . Referring to FIGS. 5A and 5B , a stack-structure according to the modification example may include gate patterns 220 L, 220 a , 220 and 220 U and insulation patterns 210 and 210 U that are stacked alternately and repeatedly. A lowermost gate pattern 220 L in the stack-structure may be a ground selection gate, and an uppermost gate pattern 220 U in the stack-structure may be a string selection gate. The gate pattern 220 a just on the lowermost gate pattern 220 L may be used as a cell gate, a dummy cell gate or a second ground selection gate. The gate patterns 220 between the gate pattern 220 a just on the lowermost gate pattern 220 L and the upper gate pattern 220 U may be used as cell gates.
The gate patterns 220 L, 220 a and 220 under a string selection gate, as illustrated in FIGS. 5A and 5B , may have a flat plate shape. The uppermost gate pattern 220 U corresponding to the string selection gate may have a line shape that is extended in the first direction. The uppermost gate pattern 220 U may be provided in plurality, and the uppermost gate patterns 220 U may be extended side by side in the first direction. The bit line 170 may be extended in the second direction and cross over the uppermost gate pattern 220 U. Like the uppermost gate pattern 220 U, an uppermost insulation pattern 210 U on the uppermost gate pattern 220 U may also be extended in the first direction.
The vertical active pattern 130 a may pass through the stack-structure and be extended into the recess region 120 under it. The lowermost gate pattern 220 L corresponding to the ground selection gate may be disposed on the common source region 105 in the substrate 100 . The entire lower surface of the lowermost gate pattern 220 L may substantially overlap with the common source region 105 . According to the modification example, the gate dielectric layer 150 d may be disposed between the vertical active pattern 130 a and the inner sidewall of an opening 115 passing through the stack-structure. The gate dielectric layer 150 d may be substantially extended vertically. The opening 115 and the recess region 120 may be self-aligned. The gate dielectric layer 150 d may be extended into the recess region 120 . According to an embodiment of the inventive concept, the lower end of the gate dielectric layer 150 d in the recess region 120 may be disposed on a level higher than the lower surface of the recess region 120 .
A lower interlayer dielectric 163 may be disposed between the uppermost gate patterns 220 U. An upper surface of the lower interlayer dielectric 163 may be coplanar with an upper surface of the uppermost insulation pattern 210 U. An upper interlayer dielectric 165 may be disposed on the lower interlayer dielectric 163 and the uppermost gate patterns 220 U. The insulation patterns 210 and 210 U may include oxide, nitride and/or oxynitride. The gate patterns 220 L, 220 a , 220 and 220 U may include at least one of a doped semiconductor (for example, doped silicon), a metal (for example, tungsten and others) or a conductive metal nitride (for example, a titanium nitride, a tantalum nitride and others).
The elements of the above-described modification examples may be combined or replaced. For example, the capping semiconductor pattern 175 of FIG. 2A may be disposed on the vertical active pattern 130 or 130 a that has been disclosed in FIG. 1B, 3A, 4A or 5B .
FIGS. 6A to 6H are cross-sectional views taken along line □-□′ of FIG. 1A for describing a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 6A , a well region 102 may be formed by providing a first conductive dopant into the substrate 100 . A common source region 105 may be formed by providing a second conductive dopant into the upper portion of the well region 102 . Insulation layers 110 and sacrificial layers 112 may be alternately and repeatedly stacked on the common source region 105 . For example, the insulation layers 110 may be formed as oxide layers. The sacrificial layers 112 may be formed of materials having an etch selectivity with respect to the insulation layers 112 . For example, the sacrificial layers 112 may be formed as nitride layers.
Referring to FIG. 6B , an opening 115 and a recess region 120 may be formed by sequentially patterning the insulation layers 110 , sacrificial layers 112 and the substrate 100 . The opening 115 may pass through the insulation layers 110 and sacrificial layers 112 , and the recess region 120 may be formed in the common source region 102 under the opening 115 (i.e., in a portion of the substrate 100 ). The recess region 120 is self-aligned in the opening 115 by sequentially patterning the insulation layers 110 and sacrificial layers 112 and the substrate 100 . The recess region 120 may pass through the common source region 105 , and the bottom surface of the recess region 120 may be disposed on a level lower than the lower surface of the common source region 105 . Therefore, the well region 102 may be exposed to the bottom surface of the recess region 120 , and the common source region 105 may be exposed to the inner sidewall of the recess region 120 . A high concentration region 122 may be formed by providing the first conductive dopant into the well region 102 through the bottom surface of the recess region 120 . The high concentration region 122 of the first conductive dopant may be higher than another portion of the well region 102 . That is, due to the high concentration region 122 , the well region 102 may partially have a high dopant concentration.
Referring to FIG. 6C , a semiconductor layer may be conformally formed on the substrate 100 having the opening 115 and the recess region 120 . Therefore, the semiconductor layer may be formed to have a substantially uniform thickness on the inner surface of the recess region 120 and an inner sidewall of the opening 115 . The semiconductor layer may contact the inner surface (i.e., an inner sidewall and a bottom surface) of the recess region 120 . The semiconductor layer may be formed in a chemical vapor deposition process and/or an atomic layer deposition process. A filling dielectric layer may be formed on the semiconductor layer to fill the opening 115 . For example, the filling dielectric layer may be formed as an oxide layer. By planarizing the filling dielectric layer and the semiconductor layer until the uppermost insulation layer 110 is exposed, a vertical active pattern 130 and a filling dielectric pattern 132 may be formed in the opening 115 and the recess region 120 .
Referring to FIG. 6D , a trench 135 may be formed by sequentially patterning the insulation layers 110 and sacrificial layers 112 , such that insulation patterns 110 a and the sacrificial patterns 112 a being alternately and repeatedly stacked may be formed at a side of the trench 135 . The insulation patterns 110 a and sacrificial patterns 112 a may include the opening 115 . That is, the vertical active patterns 130 may sequentially pass through the insulation patterns 110 a and the sacrificial patterns 112 a being alternately and repeatedly stacked on the substrate 100 . Sidewalls of the sacrificial patterns 112 a and the insulation patterns 110 a are exposed to the trench 135 .
Referring to FIG. 6E , empty regions 140 may be formed by removing the sacrificial patterns 112 a exposed to the trench 135 . Each of the empty regions 140 corresponds to a region from which the each sacrificial pattern 112 a is removed. The empty regions 140 may expose some portions of the sidewall of the vertical active pattern 130 , respectively.
Referring to FIG. 6F , a gate dielectric layer 150 may be conformally formed on the substrate 100 having the empty regions 140 . Therefore, the gate dielectric layer 150 may be conformally formed on the inner surfaces of the empty regions 140 . The gate dielectric layer 150 , as described above with reference to FIGS. 1B and 1C , may include the tunnel dielectric layer, the charge storage layer and the blocking dielectric layer.
A gate conductive layer 155 filling the empty regions 140 may be formed on the substrate 100 having the gate dielectric layer 150 . The gate conductive layer 155 may also be formed in the trench 135 . Herein, the gate conductive layer 155 may partially fill the trench 135 . Therefore, a space surrounded by the gate conductive layer 155 may be formed in the trench 135 . A bottom surface of the space may be lower than an inner-upper surface of the lowermost empty region 140 .
Referring to FIG. 6G , the gate patterns 155 L, 155 a 1 , 155 a and 155 U respectively filling the empty regions 140 may be formed by etching the gate conductive layer 155 . The gate patterns 155 L, 155 a 1 , 155 a and 155 U are separated by the etching process of the gate conductive layer 155 . According to an embodiment of the inventive concept, the etching process of the gate conductive layer 155 may be an isotropic etching process. The insulation patterns 110 a and the gate patterns 155 L, 155 a 1 , 155 a and 155 U, being alternately and repeatedly stacked on the substrate 100 , may be included in a stack-structure. Subsequently, a device isolation insulation layer 160 may be formed to fill the trench 135 .
Referring to FIG. 6H , the device isolation insulation layer 160 and the gate dielectric layer 150 may be planarized until the uppermost insulation pattern among the insulation patterns 110 a is exposed. Therefore, a device isolation pattern 160 a may be formed in the trench 135 . Subsequently, by forming the interlayer dielectric 165 , contact plug 167 and bit line 170 of the FIG. 1B on the substrate 100 , the 3D semiconductor memory device that has disclosed in FIGS. 1A, 1B and 1C may be implemented. According to the above-described 3D semiconductor memory device, the opening 115 and the recess region 120 can be formed in self-alignment by sequentially patterning the insulation layers 110 , the sacrificial layers 112 and the substrate 100 (i.e. the common source region 105 ). Therefore, the 3D semiconductor memory device can be implemented which has excellent reliability and is optimized for high integration. Next, a method of fabricating the 3D semiconductor memory device that has been disclosed in FIG. 2A will be described below with reference to the accompanying drawings. The method may include the methods that have been described above with reference to FIGS. 6A and 6B .
FIGS. 7A to 7D are cross-sectional views taken along line □-□′ of FIG. 1A for describing a modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept.
Referring to FIGS. 6B and 7A , a protection dielectric layer 173 may be conformally formed on the substrate 100 having the opening 115 and the recess region 120 , and the protection dielectric layer 173 may be etched by a blanket anisotropic etching process until the bottom surface of the recess region 120 is exposed. As illustrated in FIG. 7A , therefore, the protection dielectric layer 173 may be formed on the sidewalls of the recess region 120 and the opening 115 . The protection dielectric layer 173 may include a dielectric material having an etch selectivity with respect to the sacrificial layer 112 . For example, the protection dielectric layer 173 may be formed of oxide.
Subsequently, a semiconductor layer may be formed, a filling dielectric layer may be formed on the semiconductor layer, and the filling dielectric layer and the semiconductor layer may be planarized. Therefore, the vertical active pattern 130 and the filling dielectric pattern 132 may be formed in the opening 115 and the recess region 120 . The vertical active pattern 130 may contact the bottom surface of the recess region 120 . The protection dielectric layer 173 may be disposed between the vertical active pattern 130 and the inner sidewalls of the opening 115 and the recess region 120 .
Referring to FIG. 7B , the upper ends of the vertical active pattern 130 , filling dielectric pattern 132 and protection dielectric layer 175 may be recessed lower than the upper surface of the uppermost insulation layer 110 . Subsequently, a capping semiconductor layer filling the opening 110 may be formed on the substrate 100 , and a capping semiconductor pattern 175 may be formed by planarizing the capping semiconductor layer until the uppermost insulation layer 110 is exposed. The capping semiconductor pattern 175 may cover the recessed upper ends of the vertical active pattern 130 , filling dielectric pattern 132 and protection dielectric layer 175 .
Subsequently, the trench 135 may be formed by sequentially patterning the insulation layers 110 and the sacrificial layers 112 . In this case, as described above, the insulation patterns 110 and the sacrificial patterns 112 a that are alternately and repeatedly stacked may be formed at a side of the trench 135 .
Referring to FIG. 7C , the sacrificial patterns 112 a exposed to the trench 135 may be removed. Therefore, the empty regions 140 may be formed which respectively exposes some portions of the protection dielectric layer 173 disposed on the sacrificial patterns 112 a and the vertical active patterns 130 . As described above, the protection dielectric layer 173 has an etch selectivity with respect to the sacrificial patterns 112 a , and thus it can protect the vertical active pattern 130 from a process of removing the sacrificial patterns 112 a . The protection dielectric layer 173 may be used as an etch stop layer in the process of removing the sacrificial patterns 112 a . Subsequently, the exposed portions of the protection dielectric layer 173 may be removed. Therefore, the empty regions 140 may expose some portions of the side wall of the vertical active pattern 130 , respectively. When removing the exposed portions of the protection dielectric layer 173 , the protection dielectric patterns 173 a may be formed between the vertical active pattern 130 and the insulation patterns 110 a and between the vertical active pattern 130 and the inner sidewall of the recess region 120 . The protection dielectric patterns 173 a correspond to remaining portions of protection dielectric layer 173 .
Referring to FIG. 7D , the gate dielectric layer 150 may be conformally formed on the substrate 100 having the empty regions 140 , and the gate patterns 155 L, 155 a 1 , 155 a and 155 U respectively filling the empty regions 140 may be formed. Afterwards, the device isolation pattern 160 a filling the trench 135 may be formed. Subsequently, by forming the interlayer dielectric 165 , contact plug 167 and bit line 170 of FIG. 2A , the 3D semiconductor memory device of FIG. 2A can be implemented.
The features of a method, that fabricates the 3D semiconductor memory device that has been disclosed in FIG. 2B , may have a process of forming the lower surface of the recess region 120 higher than the lower surface of the common source region 105 and a process of forming the counter-doped region 122 a by counter-doping the common source region 105 under the bottom surface of the recess region 120 with the first conductive dopant. Other processes may be the same as the processes that have been described above with reference to FIGS. 7A to 7D .
Next, a method of fabricating the 3D semiconductor memory device that has been disclosed in FIG. 3A will be described below with reference to the accompanying drawings. The method may include the methods that have been described above with reference to FIGS. 6A and 6B .
FIGS. 8A to 8F are cross-sectional views taken along line □-□′ of FIG. 1A for describing other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept.
Referring to FIGS. 6B and 8A , a first sub-layer 147 may be conformally formed on the substrate 100 having the opening 115 and the recess region 120 . The first sub-layer 147 may be conformally formed on the inner sidewall of the opening 115 and the inner surface of the recess region 120 . A first semiconductor layer 121 may be conformally formed on the substrate 100 having the first sub-layer 147 .
Referring to FIG. 8B , portions of the first sub-layer 147 and the first semiconductor layer 121 disposed on the bottom surface of the recess region 120 may be removed. At this point, portions of the first sub-layer 147 and the first semiconductor layer 121 disposed outside opening 115 may also be removed. Therefore, the first sub-layer 147 and the first semiconductor pattern 123 that are sequentially stacked on the sidewalls of the recess region 120 and opening 115 may be formed. the first semiconductor pattern 123 correspond to a portion of the first semiconductor layer 121 . According to an embodiment of the inventive concept, by blanket-anisotropic-etching the first semiconductor layer 121 and the first sub-layer 147 until the bottom surface of the recess region 120 is exposed, the first semiconductor pattern 123 may be formed. The first semiconductor pattern 123 may not contact the inner surface of the recess region 120 by the first sub-layer 147 .
Referring to FIG. 8C , subsequently, by isotropic-etching the first sub-layer 147 , at least one portion of the inner sidewall of the recess region 120 may be exposed. At this point, a portion of the first semiconductor pattern 123 in the recess region 120 may also be etched.
Referring to FIG. 8D , subsequently, a second semiconductor layer may be conformally formed on the substrate 100 , a filling dielectric layer filling the opening 115 may be formed on the second semiconductor layer. The second semiconductor layer may contact the first semiconductor pattern 123 , and also the second semiconductor layer may contact the bottom surface and exposed inner sidewall of the recess region 120 . By planarizing the second semiconductor layer and the filling dielectric layer, a second semiconductor pattern 124 and a filling dielectric pattern 132 may be formed in the opening 115 and the recess region 120 . The second semiconductor pattern 124 may contact the bottom surface and inner sidewall of the recess region 120 and the first semiconductor pattern 123 . The first and second semiconductor patterns 123 and 124 may configure a vertical active pattern 130 a.
Referring to FIG. 8E , subsequently, the trench 135 , the insulation patterns 110 a and the sacrificial patterns 112 may be formed by sequentially patterning the insulation layers 110 and the sacrificial layers 112 . The empty regions 140 may be formed by removing the sacrificial patterns 112 . At this point, the empty regions 140 may expose some portions of the first sub-layer 147 , respectively.
Referring to FIG. 8F , a second sub-layer 149 may be conformally formed on the substrate 100 having the empty regions 140 . The second sub-layer 149 may be conformally formed on the inner surfaces of the empty regions 140 . The second sub-layer 149 may contact the first sub-layer 147 exposed to the empty regions 140 . The first and second sub-layers 147 and 149 may be included in the gate dielectric layer 150 a . The first sub-layer 147 may include at least a portion of the tunnel dielectric layer, and the second sub-layer 149 may include at least a portion of the blocking dielectric layer. Herein, one of the first and second sub-layers 147 and 149 may include the charge storage layer. According to an embodiment of the inventive concept, the first and second sub-layers 147 and 149 may be the same as the layers that have been described above with reference to FIG. 3B . Unlike this, the first and second sub-layers 147 and 149 may be replaced with the first and second sub-layers 147 a and 149 a of the FIG. 3C , respectively. Unlike this, the first and second sub-layers 147 and 149 may be replaced with the first and second sub-layers 149 b and 149 c of the FIG. 3C , respectively. Subsequently, the gate patterns 155 L, 155 a 1 , 155 a and 155 U respectively filling the empty regions 140 may be formed, and the device isolation pattern 160 a filling the trench 135 may be formed. Subsequently, the interlayer dielectric 165 , the contact plug 167 and the bit line 170 that have been disclosed in FIG. 3A may be formed. Next, a method of fabricating the 3D semiconductor memory device that has been disclosed in FIGS. 4A and 4B will be described below with reference to the accompanying drawings. The method may include the methods that have been described above with reference to FIGS. 6A and 6B .
FIGS. 9A to 9D are cross-sectional views taken along line □-□′ of FIG. 1A for describing still other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIGS. 6B to 9A , a gate dielectric layer 150 d may be conformally formed on the substrate 100 having the opening 115 and the recess region 120 . A first semiconductor layer may be conformally formed on the gate dielectric layer 150 d . Subsequently, the first semiconductor layer and the gate dielectric layer 150 d may be etched by a blanket-anisotropic-etching process until the bottom of the recess region 120 is exposed, such that a first semiconductor pattern 123 may be formed in the opening 115 and the recess region 120 . At this point, the gate dielectric layer 150 d may also be restrictively disposed in the opening 115 and the recess region 120 . The first semiconductor pattern 123 may not contact the side wall of the opening 115 and the inner surface of the recess region 120 by the gate dielectric layer 150 d.
Referring to FIG. 9B , subsequently, a second semiconductor may be conformally formed over the substrate 100 , and a filling dielectric layer may be formed on the second semiconductor layer. By planarizing the filling dielectric layer and the second semiconductor layer, a second semiconductor pattern 124 and a filling dielectric pattern 132 may be formed in the opening 115 and the recess region 120 . The first and second semiconductor patterns 123 and 124 may configure a vertical active pattern 130 a . Subsequently, a trench 135 , insulation patterns 110 a and sacrificial patterns 112 a may be formed by sequentially patterning the insulation layers 110 and the sacrificial layers 112 . According to the modification example, a portion of the lowermost insulation layer among the insulation layers 110 may remain under the trench 135 .
Referring to FIG. 9C , empty regions 140 may be formed by removing the sacrificial patterns 112 a . The empty regions 140 may expose the gate dielectric layer 150 d . Particularly, the blocking dielectric layer 143 (see FIG. 4B ) in the gate dielectric layer 150 d may be exposed. Subsequently, a gate conductive layer 155 filling the empty regions 140 may be formed on the substrate 100 .
Referring to FIG. 9D , by removing the gate conductive layer outside the empty regions 140 , gate patterns 155 L, 155 a 1 , 155 a and 155 U filling the empty regions 140 may be formed. Subsequently, the device isolation pattern 160 a filling the trench 135 may be formed, and the interlayer dielectric 165 , contact plug 167 and bit line 170 of FIG. 4A may be formed. Thus, the 3D semiconductor memory device of FIGS. 4A and 4B can be implemented. Next, a method of fabricating the 3D semiconductor memory device of FIGS. 5A and 5B will be described below with reference to the accompanying drawings.
FIGS. 10A to 10C are cross-sectional views taken along line □-□′ of FIG. 1A for describing even other modification example of a method of fabricating 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 10A , insulation layers 210 and gate layers 220 may be alternately and repeatedly stacked on the common source region 105 in the substrate 100 . The insulation layers 210 and gate layers 220 L, 220 a and 220 may have a flat plate shape. Referring to FIG. 10B , an uppermost gate pattern 220 U and an uppermost insulation pattern 210 U may be formed by patterning an uppermost insulation layer and an uppermost gate layer. The uppermost gate pattern 220 U and the uppermost insulation pattern 210 U may have a line shape that is extended in one direction as illustrated in FIG. 5A . A lower interlayer dielectric 163 may be formed on the substrate 100 , and the lower interlayer dielectric 163 may be planarized. An opening 115 and a recess region 120 may be formed by sequentially patterning the uppermost insulation pattern 210 U, the uppermost gate pattern 220 U, the insulation layers 210 , the gate layers 220 L, 220 a and 220 and the common source region 105 . The recess region 120 may be formed in self-alignment in the opening 115 . By providing a first conductive dopant through the bottom surface of the recess region 120 , a high concentration region 122 may be formed. Subsequently, a gate dielectric layer 150 d may be conformally formed over the substrate 100 , and a first semiconductor layer may be conformally formed on the gate dielectric layer 150 d . By blanket-isotropic-etching the first semiconductor layer and the gate dielectric layer 150 d until the bottom surface of the recess region 120 is exposed, a first semiconductor pattern 123 may be formed in the opening 115 and the recess region 120 .
Referring to FIG. 10C , a second semiconductor layer may be conformally formed over the substrate 100 , and a filling dielectric layer may be formed on the second semiconductor. By planarizing the filling dielectric layer and the second semiconductor layer, a second semiconductor pattern 124 and a filling dielectric pattern 132 may be formed in the opening 115 and the recess region 120 . The first and second semiconductor patterns 123 and 124 may configure a vertical active pattern 130 a . Subsequently, the upper dielectric layer 165 , contact plug 167 and bit line 170 of FIG. 5B may be formed. Thus, the 3D semiconductor memory device of FIGS. 5A and 5B can be implemented. According to the above-described method, the uppermost gate pattern 220 U may be formed, and thereafter the vertical active pattern 130 a may be formed. Unlike this, after the opening 115 , the recess region 120 and the vertical active pattern 130 a may be formed, and then the uppermost gate pattern 220 U may be formed.
When forming the uppermost gate pattern 220 U, a stack-structure having a line shape may be formed by sequentially patterning the gate layers 220 , 220 a and 220 L and insulation layers 110 under the uppermost gate pattern 220 U. In this case, the 3D semiconductor memory device of FIGS. 4A and 4B can be implemented. In other words, the 3D semiconductor memory device of FIGS. 4A and 4B may be implemented in the method that has been described above with reference to FIGS. 9A to 9D or a modified method of a portion of the fabricating method of FIGS. 10A to 10C .
FIG. 11 is a cross-sectional view illustrating a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 11 , a well region 102 doped with a first conductive dopant may be disposed in a substrate 100 . A stack-structure may be disposed on the well region 102 . The stack-structure may include insulation patterns 110 a and gate patterns 155 L, 155 a 1 , 155 a and 155 U that are alternately and repeatedly stacked on the well region 102 . A plurality of the stack-structures may be disposed on the well region 102 . The stack-structures may be spaced apart from each other. As illustrated in FIG. 1 a , the stack-structures may be extended in parallel.
A vertical active pattern 280 may pass through the stack-structure. Also, the vertical active pattern 280 may be extended into a recess region 120 that is formed in the substrate 100 under the vertical active pattern 280 . The vertical active pattern 280 may include a lower active pattern 250 and an upper active pattern 270 that are sequentially stacked. The lower active pattern 250 may fill the recess region 120 . The upper active pattern 270 may contact the inner surface (i.e., inner sidewall and bottom surface) of the recess region 120 . The lower active pattern 250 is disposed in the recess region 120 and contacts the well region 102 . The upper surface of the lower active pattern 250 may be disposed on a level higher than that of the upper surface of the substrate 100 . According to an embodiment of the inventive concept, as illustrated in FIG. 11 , the upper surface of the lower active pattern 250 may be higher than the lower surface of the lowermost gate pattern 155 L and lower than the upper surface of the lowermost gate pattern 155 L. However, the inventive concept is not limited thereto.
The upper active pattern 270 contacts the upper surface of the lower active pattern 250 . According to an embodiment of the inventive concept, the lower active pattern 250 may have a pillar shape, and the upper active pattern 270 may have a pipe shape or a macaroni shape. In this case, the inside of the upper active pattern 270 may be filled with a filling dielectric pattern 132 . The lower and upper active patterns 250 and 270 may include a semiconductor material. For example, the lower and upper active patterns 250 and 270 may include the same semiconductor material as that of the substrate 100 . As an example, when the substrate 100 is a silicon substrate, the lower and upper active patterns 250 and 270 may include silicon. According to an embodiment of the inventive concept, the lower active pattern 250 may have a single crystalline state. The upper active pattern 270 may have a poly-crystalline state. The lower active pattern 250 may be doped with a dopant having the same type as that of the well region 102 . The upper active pattern 270 may be doped with a dopant having the same type as that of the well region 102 , or may have an undoped state.
A high concentration region 122 may be disposed under the bottom surface of the recess region 120 . The high concentration region 122 may correspond to a portion of the well region 102 , and it may have a higher dopant concentration than another portion of the well region 102 . A gate dielectric layer 150 may be disposed between a sidewall of the vertical active pattern 280 and each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U. As described above in first embodiment of the inventive concept, the gate dielectric layer 150 may be extended horizontally and cover the upper surface and lower surface of each of the gate patterns 155 L, 155 a 1 , 155 a and 155 U.
According to an embodiment of the inventive concept, a common source regions 105 a may be disposed in the substrate 100 of the both sides of the stack-structure, respectively. The common source region 105 a may be laterally separated from the lower active pattern 250 . The common source region 105 a is doped with a second conductive dopant. A device isolation pattern 160 a may be disposed between the stack-structures. The common source region 105 a may be disposed under the device isolation pattern 160 a . In operating of the 3D semiconductor memory device, a horizontal channel may be generated in the well region 102 under the lowermost gate pattern 155 L. The common source region 105 a may be electrically connected to vertical channels that are formed in the vertical active pattern 280 by the horizontal channel in the well region 102 .
A contact plug 167 passing through the interlayer dielectric 165 may be connected to the upper end of the upper active pattern 270 . A drain doped with the second conductive dopant may be disposed in the upper portion of the upper active pattern 270 . The lower surface of the drain may be disposed on a level adjacent to the upper surface of the uppermost gate pattern 155 U in the stack-structure.
According to the above-described 3D semiconductor memory device, the lower active pattern 250 included in the vertical active pattern 280 fills the recess region 120 to contact the well region 102 . Therefore, reliability for the operations of a vertical cell string can be improved. Particularly, reliability for the erasing operation of cell transistors can be enhanced. Also, the vertical active pattern 280 may be divided into the lower active pattern 250 and the upper active pattern 270 . Accordingly, an independent and additional process may be performed in the lower active pattern 250 . For example, a dopant concentration may be adjusted in the lower active pattern 250 . Thus, it is very easy to control the characteristic of the 3D semiconductor memory device. As a result, the 3D semiconductor memory device can be implemented which has excellent reliability and is optimized for high integration.
Next, the modification examples of the 3D semiconductor memory device will be described below with reference to the accompanying drawings.
FIG. 12A is a cross-sectional view illustrating a modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12A , a common source region 105 may be extended to the substrate 100 under the stack-structures. For example, the entire lower surface of the lowermost gate pattern 155 L may substantially overlap with the common source region 105 . In this case, the bottom of the recess region 120 may be disposed on a level lower than the lower surface of the common source region 105 . The common source region 105 may contact a sidewall of the lower active pattern 250 .
FIG. 12B is a cross-sectional view illustrating other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12B , a vertical active pattern 280 a may include a lower active pattern 250 and an upper active pattern 270 a that are sequentially stacked. A gate dielectric layer 150 a may be disposed between the upper active pattern 270 a and each of the gate patterns 155 a 1 , 155 a and 155 U disposed next to the upper active pattern 270 a . The gate dielectric layer 150 a may include a first and a second sub-layers 147 and 149 . As described above in first embodiment of the inventive concept, the first sub-layer 147 may be extended vertically and be disposed between the upper active pattern 270 a and the insulation pattern 110 a . The second sub-layer 149 may be extended horizontally and cover the lower surface and upper surface of each of the gate patterns 155 a 1 , 155 a and 155 U.
When the upper surface of the lower active pattern 250 is disposed on a level between the levels of the lower and upper surfaces of the lowermost gate pattern 155 L, the first sub-layer 147 may not exist between the lower active pattern 250 and the lowermost gate pattern 155 L. The upper active pattern 270 a may include a first semiconductor pattern 265 and a second semiconductor pattern 267 . The first semiconductor pattern 265 may be disposed between the first sub-layer 147 and the second semiconductor pattern 267 . The first semiconductor pattern 265 may be separated from the upper surface of the lower active pattern 250 by a portion of the first sub-layer 147 . The second semiconductor pattern 267 contacts the first semiconductor pattern 265 . Also, the second semiconductor pattern 267 contacts the upper surface of the lower active pattern 250 .
The upper surface of the lower active pattern 250 may be divided into a center portion 252 c contacting the second semiconductor pattern 267 and an edge portion 252 e contacting the first sub-layer 147 . Herein, the center portion 252 c of the upper surface of the lower active pattern 250 may be disposed on a level lower than that of the edge portion 252 e . The upper active pattern 270 a including the first and second semiconductor patterns 265 and 267 may have a pipe shape or a macaroni shape. In this case, the inside of the upper active pattern 270 a may be filled with a filling dielectric pattern 132 . The first and second semiconductor patterns 265 and 267 may have a poly-crystalline state. In the modification example, the first and second sub-layers 147 and 149 may be replaced by the first and second sub-layers 147 a and 149 a of FIG. 3C or the first and second sub-layers 147 b and 149 b of FIG. 3C . Unlike this, as described above in first embodiment of the inventive concept, the first and second sub-layers 147 and 149 may be formed by another combination of a tunnel dielectric layer, a charge storage layer and a blocking dielectric layer.
FIG. 12C is a cross-sectional view illustrating still other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12C , at least edge portion of the upper surface of the lower active pattern 250 may be disposed on a level higher than the upper surface of the lowermost gate pattern 155 L. In this case, an oxide layer 255 may be disposed between the sidewall of the lower active pattern 250 and the lowermost gate pattern 155 L. The oxide layer 255 may include oxide formed by oxidizing the sidewall of the lower active pattern 250 . Therefore, the width of a first portion of the lower active pattern 250 next to the oxide layer 255 may be less than that of a second portion of the lower active pattern 250 disposed in the recess region 120 .
When the gate dielectric layer 150 a includes the first and second sub-layers 147 and 149 , the oxide layer 255 and a portion of the second sub-layer 149 may be disposed between the sidewall of the lower active pattern 250 and the lowermost gate pattern 155 L. In other words, the first sub-layer 147 may not exist between the sidewall of the lower active pattern 250 and the lowermost gate pattern 155 L. According to an embodiment of the inventive concept, when the first sub-layer 147 includes a charge storage layer, the charge storage layer may not exist between the sidewall of the lower active pattern 250 and the lowermost gate pattern 155 L. Therefore, the reliability of a ground selection transistor including the lowermost gate pattern 155 L can be improved. Moreover, the lower active pattern 250 may have a single crystalline state. Accordingly, the reliability of the ground selection transistor can be more enhanced.
FIG. 12D is a cross-sectional view illustrating even other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12D , at least the edge portion of the upper surface of a lower active pattern 250 may be disposed on a level higher than the upper surface of a gate pattern 155 a 1 that is stacked secondarily from the substrate 100 and lower than the lower surface of a gate pattern that is stacked thirdly from the substrate 100 . The secondarily-stacked gate pattern 155 a 1 and the thirdly-stacked gate pattern are disposed over the lowermost gate pattern 155 L. In this case, an oxide layer 255 may also be disposed between the secondarily-stacked gate pattern 155 a 1 and the side wall of the lower active pattern 250 .
According to the modification example, a transistor including the secondarily-stacked gate pattern 155 a 1 may be used as a dummy transistor or a second ground selection transistor. In this case, a cell gate (for example, the thirdly-stacked gate pattern 155 a ) adjacent to the secondarily-stacked gate pattern 155 a 1 may correspond to a dummy cell gate. As described above, a dummy cell transistor including the dummy cell gate has the same type as that of a cell transistor storing data, but it may not serve as a cell transistor. As an example, in operating of the cell string, the dummy cell transistor may perform only a turn-on/off function. However, the inventive concept is not limited thereto. The thirdly-stacked gate pattern may be used as a cell transistor.
FIG. 12E is a cross-sectional view illustrating yet other modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12E , the entirety of a gate dielectric layer 150 d between the sidewall of the upper active pattern 270 a and each of the gate patterns 155 a 1 , 155 a and 155 U may be substantially extended vertically and be disposed between an upper active pattern 270 a and an insulation pattern 110 a . In this case, only an oxide layer 255 may be disposed between the sidewall of the lower active pattern 250 and the lowermost gate pattern 155 L.
FIG. 12F is a cross-sectional view illustrating further modification example of a 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 12F , protection dielectric patterns 173 a may be disposed between the upper active pattern 270 a and the insulation patterns 110 a . In a fabricating process, the protection dielectric pattern 173 a may include a dielectric material for protecting the upper active pattern 270 . According to an embodiment of the inventive concept, the protection dielectric pattern 173 a may not exist between the lower active pattern 250 and the inner sidewall of the recess region 120 .
The elements of the above-described modification examples may be combined without clash or replaced. For example, the common source region 105 a of FIG. 11 may be replaced with the common source region 105 of FIGS. 12B to 12F . For example, in the 3D semiconductor memory devices of FIGS. 11 and 12A to 12F , the heights of the upper surfaces of the lower active patterns 250 may be replaced.
FIGS. 13A to 13E are cross-sectional views for describing a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 13A , a well region 102 may be formed by providing a first conductive dopant to the substrate 100 . Insulation layers 110 and sacrificial layers 112 that are alternately and repeatedly stacked may be formed on the well region 102 . A recess region 120 and an opening 115 that are sequentially stacked may be formed by sequentially patterning the insulation layers 110 , the sacrificial layers 112 and the substrate 100 . The opening 115 may pass through the insulation layers 110 and the sacrificial layers 112 , and the recess region 120 may be self-aligned in the opening 115 and be formed in the substrate 100 . The recess region 120 may expose the well region 102 .
Referring to FIG. 13B , a high concentration region 122 may be formed by providing the first conductive dopant through the bottom of the recess region 120 .
A lower active pattern 250 filling the recess region 120 may be formed. The upper surface of the lower active pattern 250 may be higher than the upper surface of the substrate 100 . Therefore, a portion of the lower active pattern 250 may fill the lower portion of the opening 115 . The lower active pattern 250 contacts the well region 102 . The lower active pattern 250 may be formed in a selective epitaxial growth process that uses the substrate 100 exposed by the recess region 120 as a seed layer. Therefore, the lower active pattern 250 may be formed in a single crystalline state. The lower active pattern 250 may be formed in a pillar shape. The lower active pattern 250 may be doped with the first conductive dopant. The lower active pattern 250 may be doped by an in-situ process when the selective epitaxial growth process is performed. Unlike this, the lower active layer 250 may be doped by an ion-implanting process.
Referring to FIG. 13C , a semiconductor layer may be conformally formed on the substrate 100 having the lower active pattern 250 , and a filling dielectric layer filling the opening 115 may be formed on the semiconductor layer. The semiconductor layer may be conformally formed on the inner sidewall of the opening 115 and the upper surface of the lower active pattern 250 . The semiconductor layer may contact the lower active pattern 250 . The semiconductor layer may be formed in a chemical vapor deposition process and/or an atomic layer deposition process. Therefore, the semiconductor layer may be formed in a poly-crystalline state.
By planarizing the filling dielectric layer and the semiconductor layer, an upper active pattern 270 and a filling dielectric pattern 132 may be formed in the opening 115 . The lower and upper active patterns 250 and 270 may configure a vertical active pattern 280 . Subsequently, a trench 135 , insulation patterns 110 a and sacrificial patterns 110 a may be formed by sequentially patterning the insulation layers 110 and the sacrificial layers 112 . The vertical active pattern 280 passes through the insulation patterns 110 a and the sacrificial patterns 112 a . Subsequently, by providing a second conductive dopant into the well region 102 under the trench 135 , a common source region 105 a may be formed.
Referring to FIG. 13D , by removing sacrificial patterns 112 a exposed to the trench 135 , empty regions 140 may be formed. According to an embodiment of the inventive concept, at least a portion of an lowermost empty regions 140 may expose a portion of the sidewall of the lower active pattern 250 . A gate dielectric layer 150 may be conformally formed on the substrate 100 having the empty regions 140 , and a gate conductive layer 155 filling the empty regions 140 may be formed.
Referring to FIG. 13E , gate patterns 155 L, 155 a 1 , 155 a and 155 U, that are respectively disposed in the empty regions 140 , may be formed by etching the gate conductive layer 155 . Subsequently, a device isolation pattern 160 a filling the trench 135 may be formed. The 3D semiconductor memory device of FIG. 11 may be implemented by forming the interlayer dielectric 165 , contact plug 167 and bit line 170 of FIG. 11 .
According to the above-described 3D semiconductor memory device, the opening 115 and the recess region 120 are formed in self-alignment, and the lower active pattern 250 fills the recess region 120 to contact the well region 102 . After, the lower active pattern 250 is formed, and then the upper active pattern 270 may be formed. Therefore, the doping concentration of the lower active pattern 250 may be independently adjusted. As a result, the 3D semiconductor memory device having superior reliability can be implemented. The features of the method of fabricating 3D semiconductor memory device that is illustrated in FIG. 12A will be described below with reference to FIG. 14 .
FIG. 14 is a cross-sectional view illustrating a modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIG. 14 , a second conductive dopant is injected into a substrate 100 having a well region 102 , such that a common source region 105 may be formed. Insulation layers 110 and sacrificial layers 112 that are alternately and repeatedly stacked may be formed on the common source region 105 . An opening 115 and a recess region 120 may be formed by sequentially patterning the insulation layers 110 , the sacrificial layers 112 and the substrate 100 . The recess region 120 may pass through the common source region 105 , and thus the bottom surface of the recess region 120 may be lower than the lower surface of the common source region 105 . The bottom surface of the recess region 120 may expose the well region 102 , and the inner sidewall of the recess region 120 may expose the common source region 105 . Successive processes may be performed identically to the process that has been described above with reference to FIG. 13A through FIG. 13E . However, the process of forming the common source region 105 a that has been described above with reference to FIG. 13C may be omitted.
FIGS. 15A to 15F are cross-sectional views illustrating other modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept. A fabricating method according to the modification example may include the method that has been described above with reference to FIG. 14 . Referring to FIGS. 14 and 15A , a lower active pattern 250 filling the recess region 120 may be formed on the substrate 100 having the opening 115 and the recess region 120 . The lower active pattern 250 may be formed identically to the process that has been described above with reference to FIG. 13B . The level of the upper surface of the lower active pattern 250 may be adjusted. In FIG. 15A , the upper surface of the lower active pattern 250 may be higher than the level of the upper surface of a lowermost sacrificial layer and lower than the level of the lower surface of a sacrificial layer just on the lowermost sacrificial layer. A first sub-layer 147 may be conformally formed on the substrate 100 having the lower active pattern 250 . A first semiconductor layer 264 may be conformally formed on the first sub-layer 147 . The first semiconductor layer 264 may be formed in a chemical vapor deposition process and/or an atomic layer deposition process. The first semiconductor layer 264 may be formed in a poly-crystalline state.
Referring to FIG. 15B , the first semiconductor layer 264 and the first sub-layer 147 may be blanket-anisotropic-etched until the upper surface of the lower active pattern 250 is exposed. Therefore, a first semiconductor pattern 265 may be formed in the opening 115 . According to an embodiment of the inventive concept, the center portion of the exposed upper surface of the lower active pattern 250 may be recessed lower than the edge portion of the upper surface of the lower active pattern 250 .
Referring to FIG. 15C , a second semiconductor layer may be conformally formed on the substrate 100 having the first semiconductor pattern 265 , and a filling dielectric layer may be formed on the second semiconductor layer. The second semiconductor layer may contact the first semiconductor pattern 265 and the center portion of the upper surface of the lower active pattern 250 . By planarizing the filling dielectric layer and the second semiconductor layer, a second semiconductor pattern 267 and a filling dielectric pattern 132 may be formed in the opening 115 . The first and second semiconductor patterns 265 and 267 may configure an upper active pattern 270 a , and the lower and upper active patterns 250 and 270 a may configure a vertical active pattern 280 a . Subsequently, a trench 135 , insulation patterns 110 a and sacrificial patterns 112 a may be formed by sequentially patterning the insulation layers 110 and the sacrificial layers 112 .
Referring to FIG. 15D , empty regions 140 may be formed by removing the sacrificial patterns 112 a . According to an embodiment of the inventive concept, the lowermost empty region of the empty regions 140 may expose the sidewall of the lower active pattern 250 , and empty regions on the lowermost empty region may expose the first sub-layer 147 . However, the inventive concept is not limited thereto. The number of empty regions for exposing the sidewall of the lower active pattern 250 may vary with the height of the edge portion of the upper surface of the lower active pattern 250 .
Referring to FIG. 15E , an oxide layer 255 may be formed by performing an oxidizing process in the exposed sidewall of the lower active pattern 250 . When the lower active pattern 250 is formed of silicon, the oxide layer 255 may be formed of a silicon oxide. The sidewall of the upper active pattern 270 a may not be oxidized by the first sub-layer 147 .
Referring to FIG. 15F , subsequently, a second sub-layer 149 may be conformally formed over the substrate 100 , and gate patterns 155 L, 155 a 1 , 155 a and 155 U respectively filling the empty regions 140 may be formed. Subsequently, an isolation pattern 160 a , an interlayer dielectric layer 165 , a contact plug 167 and a bit line 170 may be formed. Therefore, the 3D semiconductor memory device of FIG. 12C can be implemented. In the fabricating method of FIGS. 15A to 15F , the level of the upper surface of the lower active pattern 250 may be higher than the level of the upper surface of a sacrificial layer that is stacked secondarily from the upper surface of the substrate 100 and lower than the level of the lower surface of a thirdly-stacked sacrificial layer. In this case, the 3D semiconductor memory device of FIG. 12D can be implemented. In the fabricating method of FIGS. 15A to 15F , when the level of the upper surface of the lower active pattern 250 is disposed between the levels of the upper and lower surfaces of the lowermost sacrificial layer and the oxidizing process is omitted, the 3D semiconductor memory device of FIG. 12B can be implemented. In the fabricating method of FIGS. 15A to 15F , when the first sub-layer 147 is replaced by the gate dielectric layer 150 d and forming of the second sub-layer 149 is omitted, the 3D semiconductor memory device of FIG. 12E can be implemented. Next, a method of fabricating the 3D semiconductor memory device that is illustrated in FIG. 12F will be described below with reference to the accompanying drawings. The method may include the method that has been described above with reference to FIG. 14 .
FIGS. 16A and 16B are cross-sectional views illustrating still other modification example of a method of fabricating 3D semiconductor memory device according to another embodiment of the inventive concept. Referring to FIGS. 14 and 16A , after a lower active pattern 250 may be formed, a protection dielectric layer may be conformally formed on the substrate 100 . The protection dielectric layer may be blanket-anisotropic-etched until the upper surface of the lower active pattern 250 is exposed. Therefore, a protection dielectric layer 173 may be 3 formed to have a spacer shape in the sidewall of the opening 115 . Subsequently, a semiconductor layer may be conformally formed, and a filling dielectric layer may be formed. The filling dielectric layer and the semiconductor layer may be planarized, such that an upper active pattern 270 and a filling dielectric pattern 132 may be formed in the opening 115 .
Subsequently, the upper ends of the protection dielectric layer 173 , upper active pattern 270 and filling dielectric pattern 132 may be recessed, and then a capping semiconductor pattern 175 may be formed. The capping semiconductor pattern 175 may be formed in the same process as the process that has been described above with reference to FIG. 7B . Referring to FIG. 16B , a trench 135 , insulation patterns 110 a and sacrificial patterns 112 a may be formed by sequentially patterning insulation layers 110 and sacrificial layers 112 . Empty regions 140 may be formed by removing the sacrificial patterns 112 a . At this point, the protection dielectric layer 173 may be used an etch stop layer. Subsequently, by removing some portions of the protection dielectric layer 173 exposed to the empty regions 140 , some portions of the sidewall of the upper active pattern 270 may be exposed. Subsequently, the 3D semiconductor memory device of FIG. 12F can be implemented by performing the method that has been described above with reference to FIGS. 13D and 13E . According to an embodiment of the inventive concept, after forming the empty regions 140 of FIG. 16B and before forming a gate dielectric layer, an oxidizing process may be performed in the exposed sidewall of the lower active pattern 250 .
The 3D semiconductor memory devices according to embodiments of the inventive concept may be implemented as various types of packages. For example, the 3D semiconductor memory devices according to embodiments of the inventive concept may be packaged in a package type such as Package on Package (PoP), Ball Grid Arrays (BGAs), Chip Scale Packages (CSPs), Plastic Leaded Chip Carrier (PLCC), Plastic Dual In-Line Package (PDIP), Die In Waffle Pack (DIWP), Die In Wafer Form (DIWF), Chip On Board (COB), Ceramic Dual In-Line Package (CERDIP), Plastic Metric Quad Flat Pack (MQFP), Thin Quad Flat Pack (TQFP), Small Outline Package (SOP), Shrink Small Outline Package (SSOP), Thin Small Outline Package (TSOP), Thin Quad Flat Pack (TQFP), System In Package (SIP), Multi Chip Package (MCP), Wafer Level Stack Package (WLSP), Die In Wafer Form (DIWF), Die On Waffle Package (DOWP), Wafer-level Fabricated Package (WFP) and Wafer-Level Processed Stack Package (WSP).
A package on which the 3D semiconductor memory device according to embodiments of the inventive concept is mounted may further include at least one semiconductor device (for example, a controller, a memory device and/or a hybrid device) performing another function.
FIG. 17 is a block diagram schematically illustrating an example of an electronic system including a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 17 , an electronic system 1100 according to an embodiment of the inventive concept may include a controller 1110 , an input/output (I/O) unit 1120 , a memory device 1130 , an interface 1140 , and a bus 1150 . The controller 1110 , the input/output (I/O) unit 1120 , the memory device 1130 and/or the interface 1140 may be connected through the bus 1150 . The bus 1150 corresponds to a path for transferring data.
The controller 1110 may include at least one of a microprocessor, a digital signal processor, a microcontroller, and logical devices for performing a function similar to the functions of the elements. The input/output unit 1120 may include a keypad, a keyboard, a display device and others. The memory device 1130 may store data and/or commands. The memory device 1130 may include at least one of the 3D semiconductor memory devices according to embodiments of the inventive concept. Also, the memory device 1130 may further include another type of semiconductor memory device (for example, Phase-change Random Access Memory (PRAM), Magnetoresistive Random Access Memory (MRAM), Dynamic Random Access Memory (DRAM) and/or Static Random Access Memory (SRAM)). The interface 1140 may transmit data to a communication network or receive data from the communication network. The interface 1140 may have a wired type or a wireless type. For example, the interface 1140 may include an antenna or a wired/wireless transceiver. Although not shown, the electronic system 1100 is a working memory device for improving the function of the controller 1110 , and may further include a high-speed DRAM and/or a high-speed SRAM.
The electronic system 1100 may be applied to Personal Digital Assistants (PDAs), portable computers, web tablets, wireless phones, mobile phones, digital music players, memory cards, and all electronic devices for transmitting/receiving information at a wireless environment.
FIG. 18 is a block diagram schematically illustrating an example of a memory card including a 3D semiconductor memory device according to an embodiment of the inventive concept. Referring to FIG. 18 , a memory card 1200 according to an embodiment of the inventive concept may include a memory device 1210 . The memory device 1210 may include at least one of the 3D semiconductor memory devices according to embodiments of the inventive concept. Also, the memory device 1210 may further include another type of semiconductor memory device (for example, PRAM, MRAM, DRAM and/or SRAM). The memory card 1200 may include a memory controller 1220 for controlling data exchange between a host and the memory device 1210 .
The memory controller 1220 may include a processing unit 1222 for controlling the overall operation of the memory card 1200 . Also, the memory controller 1220 may include an SRAM 1221 that is used as the working memory of the processing unit 1222 . Furthermore, the memory controller 1220 may further include a host interface 1223 and a memory interface 1225 . The host interface 1223 may include a data exchange protocol between the memory card 1200 and the host. The memory interface 1225 may connect the memory controller 1220 and the memory device 1210 . In addition, the memory controller 1220 may further include an error correction block (ECC) 1224 . The error correction block 1224 may detect and correct the error of data that is read from the memory device 1210 . Although not shown, the memory card 1200 may further include a ROM that stores code data for interfacing with the host. The memory card 1200 may be used as a portable data memory card. On the contrary, the memory card 1200 may be implemented as a Solid State Disk (SSD) that may replace the hard disk of a computer system.
According to the above-described 3D semiconductor memory device, the vertical active pattern can be disposed in the recess region of the common source region and be connected to the well region. Therefore, the distance between the vertical active pattern and the common source region can be minimized, and also, the vertical active pattern can be connected to the well region. As a result, the 3D semiconductor memory device which has excellent reliability and is optimized for high integration can be implemented.
The above-disclosed subject matter is to be considered illustrative and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments, which fall within the true spirit and scope of the inventive concept. Thus, to the maximum extent allowed by law, the scope of the inventive concept is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description. | Three-dimensional (3D) nonvolatile memory devices include a substrate having a well region of second conductivity type (e.g., P-type) therein and a common source region of first conductivity type (e.g., N-type) on the well region. A recess extends partially (or completely) through the common source region. A vertical stack of nonvolatile memory cells on the substrate includes a vertical stack of spaced-apart gate electrodes and a vertical active region, which extends on sidewalls of the vertical stack of spaced-apart gate electrodes and on a sidewall of the recess. Gate dielectric layers extend between respective ones of the vertical stack of spaced-apart gate electrodes and the vertical active region. The gate dielectric layers may include a composite of a tunnel insulating layer, a charge storage layer, a relatively high bandgap barrier dielectric layer and a blocking insulating layer having a relatively high dielectric strength. | 7 |
This is a continuation-in-part of Ser. No. 677,937, filed Dec. 14, 1984 and now abandoned.
TECHNICAL FIELD
This invention relates to a beverage which increases the rate of gastric emptying and is useful in rapidly rehydrating dehydrated individuals.
BACKGROUND ART
It is well-known that increased physical exertion, particularly in hot and/or humid environments, significantly reduces the level of various salts, particularly through perspiration. In order to replace the loss of fluids and salts in the body during exercise, various beverages have been developed.
U.S. Pat. No. 4,042,684 to Kahm, discloses a dietetic beverage containing sugar, sodium chloride, potassium chloride and citric acid for supplementing sugars and salts in a mammalian body, depleted thereof during vigorous physical exercise.
Epting, U.S. Pat. No. 4,448,770, discloses a dietetic beverage adapted for consumption by humans, to maintain the balance of body fluids during periods of fluid depletion. The beverage contains potassium ion, calcium ion, magnesium ion and sucrose, with each of the potassium, calcium and magnesium ions in the form of a soluble salt.
U.S. Pat. No. 4,592,909 to Winer et al., discloses a fluid replacement drink to replace electrolytes lost during periods of strenuous activity. The beverage companies water with very minor amounts of sodium, potassium, calcium and magnesium.
SUMMARY OF THE INVENTION
The present invention relates to a beverage which provides the much needed liquid and salt replenishment to a dehydrated body. In particular, it is addressed to those individuals exerting themselves in medium to heavy levels of exercise. It has been found that the addition of a specified level of L-aspartyl-L-phenyl-alanine methyl ester, hereinafter APM, actually increases the rate of gastric emptying over the rate of water alone. In addition to APM, this beverage includes levels of certain elements which the body also loses during periods of physical exertion, namely sodium, calcium, and potassium. In addition to increasing the rate of gastric emptying, APM also acts as a sweetening agent, so as to make the beverage more palatable. Although APM provides these two necessary functions, it is also necessary to include carbohydrates for energy, such as fructose and glucose.
The products within the scope of this invention may take a variety of forms. For instance, the product may be manufactured and sold as a single-strength beverage for direct consumption by the consumer. Alternatively, the product may be in the form of an aqueous concentrate or syrup which is diluted with water to yield a beverage which fulfills all the requirements of this invention. The product may also be in dry form, such as a powder or a tablet which is dissolved in water to yield the novel beverage of this invention.
DETAILED DESCRIPTION
An edible sodium salt, dissolved in a beverage, is present in an amount sufficient to provide from about 0.025 to about 0.042% by weight sodium, as based on the weight of the aqueous beverage, as consumed. The sodium may be added in the form of any convenient edible salt, such as sodium chloride. Sodium chloride is the preferred form, and is preferably present in the beverage in an amount of about 0.02 to about 0.06% by weight to provide part of the required sodium content.
Chloride ion is present in the beverage in an amount of about 0.01 to about 0.07% by weight, preferably, 0.025 to about 0.054%. Chloride ion may be conveniently provided in the form of the potassium or sodium salt. When chloride is included as sodium chloride, the amount of sodium chloride may be sufficient to supply both the sodium and chloride requirements. Otherwise, additional chloride or sodium salt, such as potassium chloride or sodium citrate may be used.
Citric acid or water-soluble salts thereof such as sodium or potassium citrate, are present in the beverage in an amount effective to provide 0.05 to 0.15% by weight citric acid. The citric acid is preferably added in as a salt and not as free citric acid, since the free acid tends to inhibit the emtpying of the stomach, a negative affect not experienced when a salt is used as the source of citric acid.
Incorporation of APM in the beverage has been found to increase the rate of gastric emptying, i.e., the rate at which a liquid empties from the stomach. The increase has been found to be in the range of from about 5 to about 10% of an emptying rate increase. The amount of APM to be used is from about 0.02 to about 0.06% by weight of the final product, preferably about 0.02 to about 0.04% APM.
In addition to APM, carbohydrate sweeteners are included at very low levels to provide energy. The level of the carbohydrates must be kept low due to the constraints on the beverage both in respect to solids content and carbohydrate content. Higher levels of either have been found to interfere with the rapidity of hydration. It has been found that fructose can be tolerated at levels of up to and including 5% by weight, with the preferable level of fructose being 2.0 to 3.5%. At those levels, fructose does not have a slowing effect on the rate of emptying. In addition, glucose may be added to the beverage at levels of from 0.9% to 1.8% with preferably 0.9%, the total amount of fructose and glucose never being greater than 5%. The preferred beverage contains 0.9% glucose and no fructose.
Conventional flavoring and coloring agents may be added as desired, subject only to the mentioned constraints on solids and carbohydrate content. There are many suitable water-soluble coloring and flavoring agents which can be used to provide beverages within these constraints, and it is a feature and advantage of the present invention that a wide variety of these conventional ingredients can be used to provide palatable beverages of wide variety. Suitable flavoring and coloring agents include those which are conventional in the aqueous beverage field and are used in amounts known to those skilled in the art.
EXAMPLE I
Dogs with chronically implanted gastric fistulae are given 300 mls of water or other beverage. After 15 minutes, the stomach is drained and rinsed. Gastric emptying is calculated as the difference in volume with corrections for gastric secretion by use of a marker. Emptying rate is expressed as percent emptied.
In multiple trials, dogs were given 300 mls of water and after 15 minutes the rate of gastric emptying was evaluated. Thereafter, the dogs were given 300 mls of either 0.02% or 0.04% APM solution. The effect of APM was judged by the difference between the average emptying rates of APM solutions and the average emptying rate of water, where each beverage was tested at least four times per day.
______________________________________% Emptied per 15 min.(mean ± SE)______________________________________H.sub.2 O 65.8 ± 2.4.02% APM 73.3 ± 2.3.04% APM 69.4 ± 2.5______________________________________
Statistical test showed that both APM solutions emptied faster than water.
EXAMPLE II
Six dogs were tested following the procedure outlined above, in Example I. Five formulations were used, all each of variation of the present invention. Each beverage was tested at least 3 times per day.
______________________________________Beverages, percent composition(grams/100 ml) B1 B2 B3 B4 B5______________________________________Fructose -- -- -- 2.0 2.0Glucose 0.9 0.9 -- -- --NaCl 0.03 0.03 0.03 0.03 0.03Na.sub.3 Citrate 0.06 0.06 0.06 0.06 0.06K.sub.3 Citrate 0.05 0.05 0.05 0.05 0.05CaC1.sub.2 0.025 0.025 0.025 0.025 0.025Citric Acid 0.01 0.01 0.01 0.01 0.01APM -- 0.02 0.02 -- 0.02Emptied per 15 min.(mean + SE) B1 71.6 ± 1.5 B2 69.9 ± 2.0 B3 66.3 ± 2.7 B4 72.5 ± 3.2 B5 63.6 ± 2.6 H.sub.2 O 65.8 ± 2.4______________________________________
B 1 , B 2 and B 4 emptied significantly faster than water. B 3 , B 5 and water emptied similarly. | A flavored and sweetened aqueous beverage which rapidly rehydrates dehydrated individuals, containing specified amounts of water, sodium chloride, citric acid and APM. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to an apparatus for fixturing workpieces that are to be drilled, more specifically, to a drilling fixture that can be used for the precision drilling of holes in workpieces of different shapes and sizes.
[0003] 2. Description of the Related Art
[0004] It is prior-art practice, for example, in the case of drilling holes in workpieces to use a hand drill with a center punch for marking the location to be drilled. This practice has the disadvantage that the drill bit can walk on the workpiece thereby causing a marring of the workpiece or causing the hole to be drilled at an improper location. Also, there is the disadvantage that since the drill bit is not oriented or guided with respect to the workpiece the drilled hole will not be drilled at the proper angle with respect to the axis, plane, surface, or diameter of the workpiece.
[0005] In order to deal with these problems it is known from the prior art to use a drill press and to set the workpiece up with clamps and fixtures. This solution has the disadvantages that it is quite expensive to own a drill press and the space required for a drill press can be quite large. Furthermore, it is very time consuming to set up the workpiece for drilling holes, especially for a part, which requires multiple holes drilled at different center distances along its length. A further disadvantage is that there is a limitation to the length of a workpiece which may have a hole drilled along its longitudinal axis (the length of the workpiece is limited by the working height of the drill press).
[0006] Accordingly, prior art drilling devices have the disadvantages that they do not provide a satisfactory solution for quickly setting up and accurately drilling a hole in the workpiece by securing the work piece for facilitating any hole placement (i.e., along the longitudinal axis, plane, or diameter of the workpiece, perpendicular to the longitudinal axis of the workpiece, or making multiple holes at any given center distance).
SUMMARY OF THE INVENTION
[0007] It is accordingly an object of the invention to provide a drilling fixture which overcomes the above-mentioned disadvantages of the heretofore-known devices of this general type and which provides a drilling fixture that is accurate, easily manufactured, easy to maintain, quick and simply to use, has a great deal of versatility, and is reliable.
[0008] The present invention has the advantages that it is not restricted to just two holes at any center distance, it can be a multitude of hole locations and center distances. It securely clamps or locates over a specific hole location and because of its construction, it will not allow a drill bit to slip, mar, misalign or scratch plated or painted surfaces. This is especially important on painted or other finished workpieces. The present invention has the capability of drilling multiple work pieces exactly alike.
[0009] The simplicity of the present invention allows anyone with various skill levels to successfully use the drilling fixture. It is very lightweight and extremely portable.
[0010] The present invention is applicable in the following fields of use: pipe fitting and plumbing instances, fabricating shops (steel, wood, etc.); welding shops (positioning weldments etc.); in medical fields (accuracy in bone repair and reinforcing plates to be located, drilled and screwed); and irrigation (adding sprinklers to existing lines by accurately drilling and tapping for a specific nipple size).
[0011] The present invention is convenient to use for the following applications: for locating holes to be drilled in round bars and dowel tubes; accurate drilling of bar stock (round, square, hex or rectangular) perpendicularly or at other angles; drilling, with a high level of accuracy, a hole in the end of any length work piece (dowels etc.); drilling out a broken screw in an existing hole; and accurately drilling a hole through the corner of a square bar tube or angle iron.
[0012] The present invention also achieves subsequent hole locations at perpendicular or angular locations intersecting with or being offset to previously drilled holes (such as is used in building of furniture or table legs).
[0013] The present invention will adapt to any shape work piece (i.e. square, rectangular, round, hex or elliptical). It also has a very unique feature that allows a user to drill any size through hole or blind hole in a circular helical pattern of infinite center distances and angular positions which could conceivably produce a work piece that would have a spiraling pattern for whatever length desired (such as a barber pole pattern).
[0014] With the foregoing and other objects in view there is provided, in accordance with the invention a fixturing device for holding a workpiece having a longitudinal axis. The device has a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block has holding surfaces that intersect each other at an intersection and form a v-shape. The second v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces of the second v-block. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. A cross-member adjustably attaches the first v-block to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block.
[0015] In accordance with another feature of the invention, a locating arm is mounted to the first v-block for positioning the workpiece in the direction of its longitudinal axis. A channel is formed in the first v-block for accommodating the locating arm.
[0016] In accordance with a further feature of the invention, the first and second v-blocks each have a respective groove formed therein for accommodating the cross-member. The grooves are substantially parallel to the longitudinal axis of the workpiece.
[0017] In accordance with an added feature of the invention, the locating arm is L-shaped, has a hole formed therein for receiving one of the at least one drill bushings. A slot is formed in the locating arm for adjusting a position of the locating arm in the channel.
[0018] In accordance with an additional feature of the invention a 90° radial locating arm has a hole formed therein. The 90° radial locating arm is removably and adjustably mounted to one of the cross member, the first v-block, and the second v-block. One of the at least one drill bushing is removably disposed in the hole of the 90° radial locating arm. A locating pin is insertable into the one of the at least one drill bushings and into a hole formed in the workpiece for radially locating the workpiece.
[0019] In accordance with yet another feature of the invention, a tube is removably disposed in the hole of the locating arm and a stop bar is adjustably mounted to the tube for positioning the workpiece in a direction along the longitudinal axis of the workpiece.
[0020] In accordance with yet a further feature of the invention, a 45° radial locating arm has a hole formed therein, the 45° radial locating arm is removably and adjustably mounted to one of the cross member, the first v-block, and the second v-block. One of the at least one drill bushings is removably disposed in the hole of the 45° radial locating arm. The locating pin is insertable into the one of the at least one drill bushings and into a hole in the workpiece for radially locating the workpiece.
[0021] In accordance with yet an added feature of the invention, the tube includes graduations for positioning the stop bar and the cross member includes graduations for positioning the second v-block with respect to the first v-block.
[0022] In accordance with yet an additional feature of the invention, a further drill bushing has a chamfer. A chamfer is formed in the hole of the L-shaped bracket aligning with the chamfer of the drill bushing when the further drill bushing is inserted into the L-shaped bracket. The chamfers co-axially align the hole of the L-shaped bracket with the workpiece.
[0023] In accordance with still another feature of the invention, one of the at least one drill bushings is insertable into the hole in the L-shaped bracket for drilling a hole along the longitudinal axis of the workpiece.
[0024] With the objects of the invention in view, there is also provided in accordance with the invention a fixturing device for holding a workpiece with a longitudinal axis. The device includes a v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the v-block. At least one drill bushing is removably disposed in the hole of the v-block.
[0025] In accordance with still a further feature of the invention, a channel is formed in the v-block. A locating arm for positioning the workpiece along a direction of its longitudinal axis is mounted in the channel. The locating arm is L-shaped, has a hole formed therein, and a slot formed therein for adjusting a position of the locating arm in the channel.
[0026] In accordance with a further feature of the invention, a tube is removably disposed in the hole of the locating arm and a stop bar is adjustably mounted to the tube for positioning the workpiece in a direction along the longitudinal axis of the workpiece.
[0027] In accordance with an added feature of the invention, a 90° radial locating arm has a hole formed therein, the 90° radial locating arm is removably and adjustably mounted to the v-block. One of the at least one drill bushings is removably disposed in the hole of the 90° radial locating arm. A locating pin is insertable into one of the at least one drill bushings and into a hole in the workpiece for radially locating the workpiece.
[0028] In accordance with an additional feature of the invention a 45° radial locating arm has a hole formed therein, the 45° radial locating arm is removably and adjustable mounted the v-block. One of the at least one drill bushings is removably disposed in the hole of the 45° radial locating arm. The locating pin is insertable into the at least one drill bushing and into a hole in the workpiece for radially locating the workpiece.
[0029] With the objects of the invention in view, there is also provided a fixturing device for holding a workpiece having a longitudinal axis. The device has a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm is mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block has holding surfaces that intersect each other at an intersection and form a v-shape. The second v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces of the second v-block. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block.
[0030] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0031] Although the invention is illustrated and described herein as embodied as a fixturing device for drilling workpieces, 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.
[0032] 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
[0033] FIG. 1 is a diagrammatic perspective view of the drilling fixture according to the invention as seen from the workpiece holding side with a round workpiece mounted in the drilling fixture;
[0034] FIG. 2 is a perspective view of the drilling fixture according to FIG. 1 as seen from the workpiece holding side with a square workpiece mounted in the drilling fixture;
[0035] FIG. 3 is an exploded view of the drilling fixture according to FIG. 1 as seen from the workpiece holding side;
[0036] FIG. 4 is a perspective view of the drilling fixture according to FIG. 1 as seen from the workpiece holding side with a square workpiece mounted in the drilling fixture with the v-blocks separated from the connecting bar; and
[0037] FIG. 5 is a partial perspective view of the drilling fixture according to FIG. 1 as seen from opposite the workpiece holding side showing a locating mechanism for axial drilling of the workpiece;
[0038] FIG. 6 is a partial perspective view of the drilling fixture according to FIG. 1 showing a conical locator for locating an L-shaped locating bar; and
[0039] FIG. 7 is a perspective view of the drilling fixture according to FIG. 1 as seen from the workpiece holding side, where the fixture is set up to drill a hole that is co-axial to the longitudinal axis of the workpiece.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0040] Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is seen a drilling fixture according to the invention. The drilling fixture allows for the accurate drilling of differently aligned holes in a workpiece.
[0041] The drilling fixture includes a first v-block 11 and a second v-block 21 , which are attached to each other by a mounting cross-member bar 6 . The v-blocks 11 and 21 each have respective holding or locating surfaces 114 and 124 that support the workpiece when it is being drilled. It is noted that while the angle between the holding surfaces 114 and 124 of the v-blocks 11 and 21 is illustrated as being 90° it is not necessary that the angle between the holding surfaces 114 and 124 of the v-blocks 11 and 21 be 90°. The angle can be adjusted for the types of workpieces to be handled by the drilling fixture. The holding surfaces 114 and 124 intersect each other and form a v-shape. Transverse axes of the v-blocks 11 and 21 bisect the v-shape of the v-block and are perpendicular to the longitudinal axis of the workpiece 1 , while the longitudinal axis of the v-blocks is parallel to the longitudinal axis of the workpiece 1 being held.
[0042] The first v-block 11 includes a hole 13 having an axis that is parallel to the transverse axis of the first v-block 11 . The hole 13 ( FIG. 3 ) accommodates drill bushings 14 , which can be used to drill different sized holes (based on the size of the guide hole of the drill bushing), which are perpendicular to the longitudinal axis of the workpiece 1 . The drill bushings 14 have a flat ground on the outer diameter, which prevents the drill bushing 14 from rotating by way of a set screw 15 provided in the v-block 11 .
[0043] The first v-block 11 includes a first groove 12 , which runs parallel to the longitudinal axis of the first v-block 11 . The groove 12 is used for mounting a cross-member bar 6 . The groove 12 includes a threaded hole 19 for attaching the first v-block 11 to the cross-member bar 6 . The first v-block 11 includes a second groove 31 , which runs parallel to the transverse axis of the first v-block 11 . The second groove 31 accommodates an L-shaped locating bar 7 , which will be discussed in further detail below. The L-shaped locating bar 7 is attached to the first v-block by a screw held in threaded hole 79 .
[0044] The first v-block 11 includes an L-shaped clamping arm 16 that is attached thereto and is disposed parallel to the transverse axis of the first v-block 11 . The clamping arm 16 includes a threaded hole 17 , which, accommodates a screw holder 18 for holding/clamping the workpiece 1 in position for drilling of the workpiece 1 . It is possible to hold the clamping arm 16 and thus the drilling fixture in a vise when drilling holes in the workpiece 1 .
[0045] The second v-block 21 includes a hole 23 having an axis that is parallel to the transverse axis of the second v-block 21 and also the first v-block 11 . The hole 23 ( FIG. 3 ) accommodates drill bushings 14 , which can be used to drill different sized holes (based on the size of the guide hole of the bushing), which are perpendicular to the longitudinal axis of the workpiece.
[0046] The second v-block 21 includes a groove 22 , which runs parallel to the longitudinal axis of the second v-block 21 and also the longitudinal axis of the first v-block 11 . The groove 22 ( FIG. 3 ) is used for mounting the cross-member bar 6 . The groove 22 includes a threaded hole 29 for attaching the second v-block 21 to the cross-member bar 6 .
[0047] The second v-block 21 includes a L-shaped clamping arm 26 that is disposed parallel to the transverse axis of the second v-block 21 . The clamping arm 26 includes a threaded hole 27 , which accommodates a screw holder 28 for holding/clamping the workpiece 1 in position for drilling of the workpiece 1 . It is possible to hold the clamping arm 26 in a vise when drilling holes in the workpiece 1 .
[0048] A 90° radial locating arm 8 is provided for allowing alignment of the workpiece for the drilling of holes that are located 90° in relation to an existing hole. Alternatively, the 90° radial locating arm 8 can be used to drill a hole at 90° to an existing hole. The 90° radial locating arm 8 includes a hole 81 for accepting the drill bushings 14 . A set screw 15 holds the selected drill bushing 14 in place. Locating pins 3 sized for matching the sizes of the guidance hole of the drill bushings 14 are used to locate the workpiece 1 for drilling a new hole at 90° (based on the presence of a previously drilled hole in the workpiece). The 90° radial locating arm 8 includes a slot 82 which fastens the 90° radial locating arm 8 to the cross-member bar 6 or to either one of the first and second v-blocks 11 , 21 . The slot 82 allows the 90° radial locating arm 8 to be positioned for different diameter/thickness workpieces 1 .
[0049] A 45° radial locating arm 9 is provided for allowing alignment of the workpiece 1 for the drilling of holes that are located at 45° or 135° in relation to an existing hole. Alternatively, the 45° radial locating arm 9 can be used to drill a hole at 45° to an existing hole, i.e. in the corner of a square workpiece. The 45° radial locating arm 9 includes a hole 91 for accepting the drill bushings 14 , which are held in place by a set screw 15 . Locating pins 3 are used to locate the workpiece 1 in the same manner as is done with the 90° radial locating arm 8 . The 45° radial locating arm 9 includes a slot 92 , which fastens the 45° radial locating arm 9 to the cross-member bar 6 or to either one of the v-blocks 11 and 21 . The slot 92 allows the 45° radial locating arm 9 to be positioned for different diameter/thickness workpieces 1 . Furthermore, it is possible for the 45° locating arm to be mounted in the second groove 31 of the first v-block 11 , in the same manner as the L-shaped locating bar 7 . Using the 45° radial locating arm in the second groove 31 allows the drilling fixture to be able to drill holes for joinery (picture frames). Although the radial locating arms have been disclosed as being 45° and 90°, the radial locating arms can be made at any angle desired depending on the necessary application.
[0050] The cross-member bar 6 includes a hole 61 for mounting the first v-block 11 to the cross-member bar 6 . The cross-member bar 6 also includes a slot 62 for mounting the second v-block 21 . The cross-member bar 6 also has graduations 63 for setting an exact distance of the second v-block 21 in relation to the first v-block 11 . As noted above, the slot 62 is also used for mounting the radial locating arms 8 and 9 .
[0051] The L-shaped locating bar 7 mounted in the groove 31 by a screw 78 is rotatable 180° in the groove 31 ( FIGS. 1 and 7 ). The L-shaped locating bar 7 includes a hole 71 which can accommodate the drill bushings 14 for drilling an axial hole in the end of a workpiece 1 ( FIG. 7 ). The hole 71 in the L-shaped locating bar 7 can also accommodate a tube or rod 5 that is used together with a stop bar 4 for accurately positioning and locating the workpiece 1 in the longitudinal direction ( FIG. 4 ). A set screw 15 firmly holds the drill bushings 14 or the tube 5 in place. The L-shaped locating bar 7 has a slot 72 for movably mounting the bar 7 in the groove 31 . The L-shaped locating bar 7 has an end surface 75 , which acts a stop for squarely positioning a square or rectangular workpiece 1 in the v-blocks 11 and 21 ( FIG. 2 ). The L-shaped locating bar 7 also includes graduations 73 for the positioning of the bar 7 with respect to the first v-block 11 . As shown in FIG. 6 , a conical locator drill bushing 76 is inserted into the hole 71 of the locating bar 7 . The conical locator bushing has a 45° chamfer at an end face thereof for seating the workpiece 1 , which centers the hole 71 of the locating bar 7 with the longitudinal axis of the workpiece. The locating bar 7 includes a 45° chamfer at an end face thereof that aligns with the chamfer of the locator drill bushing 76 . This allows the centering of a workpiece 1 which has a diameter greater than that of the conical locator drill bushing 76 . The use of the conical locating drill bushing 76 with the bar 7 , provides for drilling a hole that is co-axial with the longitudinal axis of the workpiece 1 .
[0052] As is shown in FIG. 3 , the rod 5 includes graduations 53 for positioning the stop bar 4 , which is mounted on the rod 5 by a hole 41 . The rod 5 has a shoulder 54 for locating the rod 5 in the hole 71 of the L-shaped locating bar 7 . The rod 5 has a flat surface 52 , for holding a set screw 15 mounted in the stop bar 4 . The set screw allows the stop bar 4 to be positioned using the graduations 53 of the rod 5 . The stop bar 4 has a slot 42 , which allows access to the screw 78 which retains the L-shaped locating bar 7 so that the L-shaped locating bar 7 may be adjusted when the stop bar 4 is in place.
[0053] The operation of the device will be described with respect to the drawings and the above-provided description.
[0054] FIG. 1 shows the device set up for drilling radial holes on the outer perimeter of the workpiece 1 . The v-blocks 11 and 21 are set in position on the cross-member bar 6 . The stop bar 4 is positioned on the rod 5 to set the longitudinal position of the workpiece 1 . Next, the workpiece 1 is clamped to the first and second v-blocks 11 and 21 by the clamping arms 16 and 26 and the screw holders 18 and 28 . Once the workpiece 1 is in position, accurately positioned radial holes may be drilled in the workpiece 1 by guiding a drill bit through the drill bushings 14 , which are mounted in the v-blocks 11 and 21 . In order to drill a hole which is indexed at 45°, 90° , or 135° the appropriate radial locating arm is attached to the cross-member bar 6 and the workpiece 1 is unclamped and rotated until the pin 3 is inserted through the radial locating arm into a previously drilled hole. The workpiece is then re-clamped, the pin is removed and additional holes can be drilled via the drill bushings 14 disposed in the v-blocks 11 and 21 .
[0055] FIG. 2 shows that a rectangular or square workpiece 1 can be placed squarely in the v-blocks 11 and 21 by abutting the end surface 75 of the L-shaped locating bar 7 against the rectangular workpiece 1 . The screw holders 18 and 28 are tightened against the workpiece 1 and the rectangular workpiece is squarely and securely positioned with respect to the v-blocks 21 and 22 .
[0056] FIG. 4 shows that holes can be drilled in a longer workpiece 1 by separating the second v-block 21 from the cross-member bar 6 . The second v-block 21 is then free to be positioned at any location on the workpiece 1 . When the drilling fixture is used in this manner the fixture is placed on a flat worktable by resting on the L-shaped clamping arms 16 and 26 of the respective v-blocks 11 and 21 .
[0057] FIG. 6 shows the use of the conical locator 76 for drilling a hole that is co-axial with the longitudinal axis of the workpiece 1 . The conical locating drill bushing 76 is placed in the hole 71 of the L-shaped locating bar 7 . The end of the workpiece is pushed against the conical locating drill bushing 76 , which in turn positions the locating bar 7 in the groove 31 so that the conical locator 76 seats itself on the workpiece 1 . The conical locating drill bushing 76 is removed and the appropriate size drill bushing 14 is inserted into the hole 71 of the L-shaped locating bar 7 and a hole is drilled in the end face of the workpiece 1 . | A fixturing device for holding a workpiece with a longitudinal axis is disclosed. The fixturing device includes a first v-block with holding surfaces that intersect each other at an intersection and form a v-shape. The first v-block has a hole formed therein with a center axis that is substantially perpendicular to the longitudinal axis of the workpiece and intersects the intersection of the holding surfaces. A clamping arm mounted to the first v-block for clamping the workpiece in the first v-block. A second v-block that is similar to the first v-block is also provided. A clamping arm is mounted to the second v-block for clamping the workpiece to the second v-block. A cross-member adjustably attaches the first v-block to the second v-block. At least one drill bushing is removably disposed in one of the hole in the first v-block and the hole in the second v-block. | 8 |
FIELD OF THE INVENTION
This invention relates to multi-ply labels and more particularly to multi-ply labels that contain removable promotional game pieces.
BACKGROUND OF THE INVENTION
An existing label used in connection with promotional games includes two plies. One ply, forming the base of the label, has an underside to which a pressure-sensitive adhesive is affixed. The opposing side of the base, the face, contains no adhesive, and may be printed with promotional or other material. In use, the underside of the base is attached to a substrate such as a paper beverage cup sold in retail outlets.
The second ply, which similarly includes a face and an underside, overlays the base of the label. The second ply contains three parallel regions that extend along the length of the ply and are separated by two parallel rows of perforations. The underside of the outer two regions contains an adhesive that couples the underside of the second ply to the face of the base ply. Between the outer regions is an intermediate region. The game piece, which contains information concerning the prize to be awarded for a particular promotion, is printed on the underside of the intermediate region. The face of the second ply may have promotional information and game-playing instructions printed thereon.
To play the promotional game a player separates the intermediate region of the second ply from the outer regions by detaching it along the perforations. Doing so exposes the surface of the game piece containing the prize information and informs the player of the remit of the promotion.
Multi-ply labels present various security and handling problems. In particular, a game piece that is coupled with the label by adjacent and supporting portions may extend from the promotional label roughly in the form of a tab to permit a player more easily to detach the game piece from the label. In situations in which a label is applied to a pliable (as opposed to a rigid) surface, or where the game piece is comparatively large, it may become temptingly easy for a party to peek at the inner surface of the game piece by bowing or otherwise distorting the surrounding pliable material or the game piece. A mechanism to preclude manipulation of a label, a game piece, or a mounting surface to compromise the game is thus highly desirable.
To prevent tampering and premature viewing of a game releasable adhesives are typically employed to secure the plies together. An adhesive is often applied to one face of a ply along with a release coating that is applied to the opposing face of the adjacent ply. Depending upon the adhesive employed, degradation can cause the adhesive to lose its effect and allow the plies to separate prematurely. Some adhesives may harden and cause the plies to adhere permanently, requiring a player to tear the game piece in order to expose it. Plies secured together by a releasable adhesive are also prone to premature separation when, for instance, a ply is inadvertently snagged by a fixed object. Moreover, despite the adhesives players can still peek within the label by sliding a thin object between the plies and thereby separating them.
Releasable adhesives cause additional problems when one desires to manufacture a promotional label that incorporates a sticker as a third ply. Such stickers may be sandwiched between the base and outer plies of the label. In order to prevent premature peeking at the face of the sticker an adhesive and release coating may optionally be applied between the face of the sticker and the opposing ply. When this is done, however, some of the adhesive or release coating may remain bound to or discolor the sticker when removed from the label.
It is an object of this invention, therefore, to provide a label which incorporates a game piece that resists tampering and manipulation that compromises the game prematurely.
Another object of this invention is to provide a tamper-resistant label that incorporates a game piece that does not require adhesives to be applied between the face of the game piece and an opposing ply.
It is another object of this invention to provide a tamper-resistant label from which a game piece can be easily separated and removed without tearing or otherwise compromising the game piece.
It is a further object of this invention to provide a tamper-resistant promotional label having a removable sticker as a game piece;
Other objects, features and advantages will become apparent to people skilled in the art by reference to this specification and the drawings appended hereto.
SUMMARY OF THE INVENTION
In one embodiment of the present invention the label is comprised of two plies, a base ply that is adhered to a substrate such as a beverage cup, and a second ply, a portion of which is adhered to the base ply. The second ply is separable into four regions--a first edge, a second circumscribing edge, a strip, and a centerpiece. The four regions are defined by five rows of perforations that when torn allow the regions to be separated. The first edge traverses a segment of the peripheral boundary of the second ply. The second circumscribing edge traverses the bulk of the remaining peripheral boundary of the second ply. The edges are coupled securely to the base ply by a suitable adhesive. The third region, a strip, separates the two edges, lies adjacent to and along the length of the first edge, and traverses the length of the second ply. The fourth region, the centerpiece, is enclosed by and coupled to the strip and the second circumscribing edge.
The strip has a tab that extends generally beyond the outer periphery of the second ply. By grasping and pulling the tab one can tear the rows of perforations that couple the strip to the edges and the centerpiece and thereby separate the strip from the second ply. Separation of the strip from the second ply also decouples one edge of the centerpiece from the label, leaving the centerpiece coupled to the label only along the second circumscribing edge. A person can then grasp the decoupled edge of the centerpiece and pull the centerpiece away from the base ply by tearing the perforations that couple the centerpiece to the second circumscribing edge. The game piece, which may be printed on the underside of the centerpiece, is thereby exposed for viewing and can subsequently be removed from the label.
The present label may optionally comprise a third ply that is sandwiched between the base and second plies. Like the second ply, the third ply is separable into four regions along five rows of perforations. The four regions correspond to the regions of the second ply and approximate the geometry and size of the regions defined in the second ply. The underside of the third ply, which lies adjacent to the base ply, is adhered to the base ply at the first edge and second circumscribing edge of the third ply. The opposed face of the third ply, at the first edge, the second circumscribing edge, and the strip, are adhered to the underside of the second ply at its first edge, second circumscribing edge, and strip, respectively. By grasping and tearing the strips from the second and third plies a player can decouple one edge of the centerpiece regions of the second and third plies from the label. By grasping the exposed edges of the centerpiece regions and pulling the regions from the label one can separate and remove the centerpiece region from the label. The opposed face of the third ply in the centerpiece region may be adhered releasably to the inner face of the second ply so that when the centerpieces have been removed from the label the centerpiece of the third ply can be separated from the centerpiece of the second ply to liberate a game piece or sticker that can optionally be readhered to another surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a two-ply label constructed according to one embodiment of the present invention, viewed from above.
FIG. 2 is an exploded view of a three-ply label constructed according to another embodiment of the present invention, viewed from above.
FIG. 3 is a top plan view of a label constructed according to the present invention showing the regions of the outermost ply, the perforations that separate the regions, and an optional score in the outermost ply.
FIG. 4 is a top plan view of the label shown in FIG. 3 from which the strip and the centerpiece of the outermost ply have been partially removed to illustrate the function of the label.
DETAILED DESCRIPTION OF THE INVENTION
One aspect of the present invention relates to the means by which a detachable game piece is coupled to and removed from a promotional label. A label construction is employed in which the periphery of a game piece is totally enclosed by the edges of the label to prevent anyone from viewing the underside of the game piece without first tearing the perforations that separate the game piece from the edges of the label. Referring particularly to FIG. 1 there is shown a label 5 from which a game piece cannot be removed without first tearing it from the edges that circumscribe the game piece.
FIG. 1 shows a label 5 in exploded view. A first or base ply 10 is formed of a material having sufficient strength to bear additional plies, to anchor those plies to a substrate surface (not shown), and to retain portions of the label 5 even upon manual removal of other portions. Base ply 10 has a face 16 and an underside 17. Underside 17 is provided with an adhesive of sufficient strength to retain it and any attached plies to a temporary holding surface (from which label 5 is eventually to be removed) and ultimately to a substrate, such as a soft drink cup, food wrapper, or other such product.
In the embodiment illustrated in FIG. 1 ply 10 includes four portions: a first edge 10A, a strip 10B, a second circumscribing edge 10C, and a centerpiece 10D. These potions are delineated from adjacent portions by weakened regions such as perforation rows 11, 12, 13, 14 and 15. Strip 10B is distinguished and manually separable from first edge 10A by perforation row 11. Strip 10B is distinguished and manually separable from centerpiece 10D and second circumscribing edge 10C by perforation row 12. Centerpiece 10D is distinguished and manually separable from strip 10B by perforation row 12, and from second circumscribing edge 10C by perforation rows 13, 14, and 15. In one embodiment the illustrated regions, perforations and separability in base ply 10 are optional because the base ply, once applied, typically need not be separated into component parts.
The geometry of the periphery of the label shown in FIG. 1 has certain features that are important to the functioning of the disclosed embodiment. In particular, the strip portion 10B of base ply 10 has a periphery that physically and visually distinguishes it from the remainder of label 5. In FIG. 1 the distinguishable periphery is a tab 18 of base ply 10 that protrudes beyond the periphery of the label at the intersection of the strip 10B with edge regions 10A and 10C.
As further shown in FIG. 1 label 5 may comprise a second ply 100. The size and geometry of ply 100 is advantageously similar to that of base ply 10. Ply 100, like ply 10, includes a face 106 and an underside 107. Ply 100 also is comprised of four portions--100A, 100B, 100C, and 100D. As is the case with the portions of ply 10, portions 100A and 100B are distinguished and separable from one another along perforation row 101, portion 100B is distinguished and separable from portions 100C and 100D along perforation row 102, and portions 100C and 100D are distinguished and separable along perforation rows 103, 104, and 105. When ply 100 is laid over ply 10, portions 100A, 100B, 100C and 100D, and rows 101, 102, 103, 104, and 105, generally overlay and correspond to their respective portion or row in ply 10. A tab 108 of strip 100B protrudes beyond adjacent edges of portions 100A and 100C and overlies tab 18. Although the geometry of ply 100 may correspond to that of ply 10, the invention is limited neither to this particular geometry nor to strict correspondence between all dimensions of the plies or the regions of which the plies are comprised.
Centerpiece 100D may contain a game piece that has been incorporated on the underside 107 of centerpiece 100D by printing the underside 107 with game indicia. Opposed face 106 of ply 100 may also be printed with promotional information and game-related information because this is the surface to which consumers will be exposed prior to playing the game. The printing of the underside and face of the game piece may occur before plies 10 and 100 are assembled into a functional promotional label.
In order to assemble plies 10 and 100 into a functional promotional label 5 the underside 107 of ply 100 at first edge 100A and second circumscribing edge 100C is coupled by suitable means to face 16 of ply 10 at first edge 10A and second circumscribing edge 10C. This coupling is preferably achieved by a known adhesive having sufficient strength to hold the first edges and second circumscribing edges of plies 10 and 100 together while strip 100B is being torn from the label 5 along perforation rows 101 and 102, and while centerpiece 100D is being torn from the label 5 along perforation rows 103, 104, and 105.
When label 5 has been assembled as described, and when the entire underside 17 of ply 10 has been adhered to a substrate, only tab 108 can be grasped and pulled readily. Because strip 100B is not adhered to the base ply, a player can grasp and pull tab 108, tear perforation rows 101 and 102, separate strip 100B from the label, and leave the remainder of the label intact. Once the strip 100B has been removed the game piece, which is contained on the underside of centerpiece 100D, can be grasped, pulled, and torn from label 5 along perforation rows 103 and 105, whereupon a player can rotate the game piece about perforation row 104. The game piece can then remain coupled to the label or, if preferred, centerpiece 100D can be again grasped and pulled in order to tear perforation row 104 and separate the game piece from the label 5.
The adhesion between the second circumscribing region and the base ply can be manipulated to improve the ease with which the centerpiece region 100D can be grasped after the strip 100B has been removed from the label. If, for instance, the second circumscribing edge 100C is adhered to the base ply 10 along its entire underside, and particularly at the points where the second circumscribing edge 100C meets the strip 100B, it may be difficult to lift and grasp centerpiece region 100D after strip 100B has been removed. Accordingly, adhesive may be omitted advantageously from beneath the circumscribing edge 100C in an area nearest either of the junctions between the circumscribing edge 100C and strip 100B, so that centerpiece region 100D can be lifted for grasping before it is torn from the circumscribing edge 100C.
The removal of strip 100B may be facilitated by the geometry of the perforations that form rows 101 and 102, as shown in FIGS. 3 and 4. The perforations in rows 101 and 102 may extend inwardly as "crow's feet" from the rows of perforations so that the perforations will engage more easily when the strip 100B is being removed and rows 101 and 102 are being torn. Similar inwardly extending perforations may also comprise perforation rows 103 and 105, which likewise assist engagement of perforations when centerpiece 100D is being removed and rows 103 and 105 are being torn. These inwardly extending perforations are generally desirable in labels constructed to require that two rows of perforations be torn at once, because it is difficult to ensure that the perforations in both rows engage continuously as the rows are torn simultaneously. These inwardly extending perforations are desirable in such a construction even though they may leave the edges of the game piece frayed once the game piece is removed.
Unidirectional perforations, which tear more cleanly than crow's feet, are generally preferred over crow's feet perforations where perforation rows readily tear. Perforation row 104 for instance, as shown in FIGS. 3 and 4, will tear readily because it is not torn at the same time as another row. Perforation row 104, accordingly, may omit crow's feet perforations and be comprised instead entirely of unidirectional perforations.
The cut-to-tie ratio, which is the length of perforations to the length between perforations in a segment for a row of perforations, can also be manipulated to facilitate tearing along a row of perforations, or to inhibit premature or accidental tearing of the perforation rows in a label. The cut-to-tie ratio can be varied, for instance, along the length of a row of perforations so that the segments in the row of perforations that have a high cut-to-tie ratio are more easily torn than other segments that have a low cut-to-tie ratio. Accordingly, in one embodiment of the present invention the cut-to-tie ratio of rows 101 and 102 is greatest in the middle of the rows of perforations in order to minimize the risk of accidental or premature rupture of perforations at the ends of the rows.
According to the foregoing construction there is achieved a label in which a game piece is totally enclosed and from which the game piece can be removed readily. The removable strip of the disclosed embodiment initiates the removal of the game piece from the label by allowing one to decouple the game piece from one of the edges of the label, thereby freeing one edge of the game piece so that it may be grasped and pulled away from the label to separate it from the label along existing perforations. It will be apparent to those skilled in the art that a game piece that is coupled to a label around its entire periphery can be decoupled from a first edge of the label by means other than a removable strip and removed from the label by means other than torn perforations. One such means would be a string that is mounted between plies at the juncture of the game piece to the label that, when pulled, would tear through the second ply and decouple the game piece from the label at one edge. The present invention is meant to encompass all means by which a game piece can be decoupled from the edges of a label in order to remove the game piece from the label.
Moreover, while the foregoing discussion has focused upon a particular label as shown and described, the invention does not depend on any particular geometry. Labels may take any number of external shapes or dimensions and still be within the scope of this invention as long as they are consistent with the principles set forth in this specification.
A further embodiment of the present invention, label 6, is disclosed by FIG. 2 in which a third ply 50 is shown sandwiched between plies 10 and 100. The third ply 50 shown in FIG. 2 corresponds generally in size and geometry to plies 10 and 100. The third ply 50 is shown further to comprise four sections, 50A, 50B, 50C, and 50D, that correspond to and lie adjacent to respective sections 10A, 10B, 10C, and 10D of ply 10, and sections 100A, 100B, 100C, and 100D of ply 100, when ply 50 is laid over ply 10 and ply 100 is laid over ply 50.
Ply 50 is shown to have an underside 57 and opposed face 56. The underside 57 of ply 50 at edge regions 50A and 50C is adhered to the opposed face 16 of ply 10 at edge regions 10A and 10C. The opposed face 56 of ply 50, at edge regions 50A and 50C, is similarly adhered to the underside 107 of ply 100 at edge regions 100A and 100C. Edge regions 100A and 100C thereby remain secured to base ply 10, as disclosed herein in a separate embodiment, despite the presence of a third ply between the two plies.
The opposed face of the third ply at strip region 50B may be adhered to the underside of the second ply at strip 100B, depending upon the game construction that is desired. If strips 100B and 50B are adhered together then they can be removed from the label at one time, which would enable a player of the game to grasp and remove centerpiece regions 50D and 100D both at once. It may be particularly advantageous to adhere strips 50B and 100B together if centerpiece regions 50D and 100D cooperate to form a game piece. This advantage can be realized when, for instance, the opposed face 56 of ply 50 at centerpiece region 50D is a sticker adhered releasably to the underside 107 of ply 100 at centerpiece region 50D.
When centerpiece region 50D is a sticker or other object that is adhered releasably to centerpiece 100D a score 111 as illustrated in FIG. 2 may advantageously be cut through the centerpiece region 100D to permit centerpiece 100D to be folded along the score in order to facilitate separation of the centerpiece 50D from centerpiece 100D.
The foregoing is provided for purposes of illustrating, explaining, and describing embodiments of the present invention. Modifications and adaptations to theses embodiments will be apparent to those skilled in the art and may be made without departing from the scope and spirit of this invention. | A label comprised of at least two coupled plies is disclosed that can incorporate a removable game on the inside face of the centerpiece region of an outer ply. An edge region on the outer ply, which circumscribes the centerpiece region, is adhered to an inner ply. A weakened region separates the edge region from the centerpiece region so that the centerpiece region is removable from the label by first decoupling a segment of the centerpiece region from the edge region of the outer ply, and then grasping and pulling the centerpiece region from the label to decouple it completely from the label. | 8 |
FIELD OF THE INVENTION
This invention relates generally to the field of methods for producing a chipped wood surfacing material having unusually high shock absorbing capabilities. This invention also relates to chipped wood having unusually high shock absorbing characteristics.
BACKGROUND OF THE INVENTION
Children's playgrounds and other recreational areas present opportunities for physical activity and challenge. Such areas often have equipment such as swings, slides, climbing nets and ladders. Because children can be expected to use equipment in unintended and unanticipated ways, playground equipment and their surrounding fall zones should be as safe as possible. The fall zone is the area under and around the equipment where protective surfacing should be present. For example, the fall zone for a slide is at least six feet from the perimeter of the slide with a possible larger fall zone at the front exit of the slide chute, depending on the height of the slide.
The Consumer Product Safety Commission has long recognized the potential hazards that exist with the use of playground equipment. A Commission study of playground equipment-related injuries treated in U.S. hospital emergency rooms indicated that the majority of injuries resulted from falls from equipment. Tinsworth, Deborah Kale, and John T. Kramer, Playground Equipment-Related Injuries and Deaths, U.S. Consumer Product Safety Commission, Washington D.C. (April 1990). These injuries were primarily falls to the ground surface below the equipment rather than falls from one part of the equipment to another part of the equipment.
Several different surfacing materials are currently used in play areas. Examples of such surfacing materials include asphalt, concrete, hard packed dirt, grass and turf, unitary synthetic materials and loose-fill materials. Unitary synthetic materials are generally rubber mats or the like. Loose-fill materials are materials such as wood mulch, sand, gravel or shredded tires.
These various types of surfacing material have different degrees of shock absorbency. Obviously, a fall onto a hard surface is more likely to cause a serious injury than a fall onto a surface with a higher degree of shock absorbency. Head impact injuries from a fall on any kind of surface have the potential for being life threatening. The more shock absorbing a surface can be made, the less likely the injury will be severe or life threatening. It should be recognized, however, that depending on the circumstances of the fall, an injury may occur even if a highly shock absorbing surface material is used in a recreational area.
Biomedical researchers have developed a testing method to determine when a head impact injury may be life threatening. This test evaluates the shock absorbing properties of a recreational area surfacing material. The test is performed by dropping an instrumented metal headform onto a sample of the material and recording the acceleration/time pulse during the impact. Researchers have established that if the peak deceleration of the headform during impact does not exceed 200 times the acceleration due to gravity (200 g's), a life-threatening head injury is not likely to occur. Handbook for Public Playground Safety, U.S. Consumer Product Safety Commission, Washington D.C. (1991) (hereinafter "Handbook for Public Playground Safety").
The term "critical height" is used to describe the shock absorbing performance of a surfacing material. It is defined as the maximum height from which the instrumented metal headform, upon impact, yields a peak deceleration of no more than 200 g's when tested in accordance with the procedure described in American Society for Testing Materials, Standard Specification for Impact Attenuation of Surface Systems Under and Around Playground Equipment, ASTM F1292 (Philadelphia, Pa.; May 1991) (hereinafter "ASTM F1292").
Table 1 gives the critical heights for various surface materials. The tests were conducted in accordance with the ASTM F1292 procedure.
TABLE 1______________________________________Critical Heights (in feet) of Tested Materials Compressed Uncompressed depth depthMaterial 6 inches 9 inches 12 inches 9 inches______________________________________Wood mulch 7 10 11 10Double shredded 6 10 11 7bark mulchUniform wood 6 7 >12 6chipsFine sand 5 5 9 5Coarse sand 5 5 6 4Fine gravel 6 7 10 6Coarse gravel 5 5 6 5______________________________________
The Americans with Disabilities Act of 1990 ("ADA") prohibits discrimination on the basis of disability in employment, public services, transportation, telecommunications and public accommodations, including many services operated by private entities. 42 U.S.C. § 1210 et seq. It prohibits denying full and equal enjoyment of "goods, services, facilities, privileges, or accommodations" to disabled individuals with respect to any place open to the public. 42 U.S.C. § 12182. Existing structures, new construction, and alterations are all within the scope of the ADA's public accommodations provisions. Title III of the ADA includes within the definition of public accommodation: "a park, zoo, amusement park, or other place of recreation;" a school, including nursery schools; a day care center; and a gymnasium, health spa, or "other places of exercise or recreation." 42 U.S.C. § 12181. Public playgrounds, therefore, should be surfaced with a material so that physically challenged individuals may have access to playground equipment.
Hard surfacing material, such as asphalt or concrete allows recreational areas to be accessible to disabled individuals. These types of surfaces, however, are not otherwise suitable for use under and around playground equipment because of the high risk for injury due to a fall on the surface. Hard packed dirt is also not recommended because its shock absorbing properties can vary considerably depending on climatic conditions such as moisture content of the soil and temperature. It can be hazardous for children to play on very dry or frozen ground because of the lack of shock absorbance of these surfaces. Similarly, grass and turf are not recommended because their effectiveness in absorbing shock during a fall can be reduced considerably due to wear and environmental conditions. Handbook for Public Playground Safety.
Loose-fill materials such as sand and gravel are more shock absorbing than concrete or hard packed dirt, but these types of surfacing material have the disadvantage of inhibiting the maneuverability of wheelchairs, walkers, tricycles, bicycles, strollers and other wheeled items. Wheeled vehicles cannot easily move across sand and gravel. Further, the critical height values for sand and gravel materials decrease when the materials are compressed. Such compression can be expected from repeated use in high traffic areas of the playground. Also, moisture in sand can cause the critical height value for this material to decrease.
A disadvantage of unitary materials is that the material itself is very expensive. Unitary materials can be as much as ten times more expensive than the inventive surfacing material. Also, the ground underneath the synthetic material often must be made level and uniform before the unitary material is laid, which can be costly process. Further, this type of material may not drain well after storms because of puddles that may form on the surface. Another disadvantage is that synthetic materials can leach chemicals into the environment.
SUMMARY OF THE INVENTION
The present invention is a novel and useful method for producing a chipped wood surfacing material having unusually high shock absorbing capability. This invention also relates to chipped wood having unusually high shock absorbing capabilities.
The invention is practiced by first harvesting trees of the Family Salicaceae, genus Populus. The harvested trees are de-limbed to form poles. The poles are processed through a knife type chipper to form wood chips. Next, the wood chips are shredded and passed through a screen with a pore size of about one inch in diameter to form wood particles. Random samples of the resulting wood particles are tested to verify that the wood particles have a critical height of at least 8 feet at an uncompressed depth of 6 inches.
The trees used as starting materials in the invention can be of the aspen or popple species. The resulting wood particles may be used as a surface material for recreational areas such as playgrounds, biking trails, hiking trails and the like. The wood particles may also be used as a surface material on other paths such as between buildings on college campuses or in business parks or at exercise facilities.
The present invention also includes manufactured wood particles with the property of a critical height of at least 8 feet at an uncompressed depth of 6 inches. The wood particles are derived from the Family Salicaceae, genus Populus. The wood particles may be derived from the aspen or popple species.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a flow diagram of the method of the present invention.
DETAILED DESCRIPTION
Trees of the Family Salicaceae (commonly called the willow or poplar Family), of the genus Populus are harvested and de-limbed to form poles. Preferably the trees are of the aspen or popple species. The poles preferably are less than about 22 inches in diameter and are processed through a knife type chipper that produces pieces of wood that will break fairly easily. The chips are further processed through a grinder/shredder until the chips are small enough to pass through a screen of a designated size. The shredding process produces a mixture of wood chips and wood particles of various sizes. Further, the shredding process introduces extrinsic air into the individual wood chips or particles. Random samples of the chipped wood are tested to verify that the wood product has a critical height of at least 8 feet at an uncompressed depth of about 6 inches.
This particular shredding process produces the unique characteristic that gives the chipped wood surfacing material its superior test results. A hammering process carried out by the grinder/shredder produces a chip that is "fluffy," a result of the bonding between the fibers in the chip being loosened but not separated, allowing air to be trapped within the chips. The shredding process separates the wood fibers on the ends of the chips, producing more trapped air between the individual particles.
The chipped wood surfacing material of this invention is suitable to be spread on playgrounds such as at schools, public parks or child care centers. The surfacing material of this invention is also suitable for spreading on paths including but not limited to bicycle trails, nature trails, hiking trails and walking paths. These paths, for example, may be in public parks or forests, college campuses, business parks, private settings or areas that are within the scope of the ADA's public accommodations provisions.
The chipped wood surfacing material is not treated with any chemicals and therefore is completely non-toxic and is an environmentally sound surfacing material. The invention is superior to asphalt or concrete because is never expands or contracts during the changing seasons. It does not generate buckles or cracks that must be patched or repaired. Further, it is more resilient than sand or gravel. The invention provides a suitable surface for wheelchairs, walkers, crutches, tricycles, bicycles and strollers because wheeled vehicles can easily move over the inventive material.
The invention will be further understood with reference to the following illustrative embodiments, which are purely exemplary, and should not be taken as limiting the true scope of the present invention as described in the claims.
EXAMPLE 1
Manufacture of Chipped Wood Surfacing Material
Trees of the aspen species were harvested and de-limbed to form poles. The poles were less than about 22 inches in diameter and were processed through a knife type chipper (Morbark) to form wood chips. The wood chips were about two to six millimeters (0.079 to 0.236 inches) thick and about 15.9 to 25.4 millimeters (5/8 to 1 inch) long.
Next, the wood chips were processed through a grinder/shredder (Farmhand 6650 Tub Grinder). The grinder was equipped with a rotor 21 inches in diameter and 40 inches long. The rotor held 40 hammers, each 0.5 inch thick, 2.75 inches wide, and 5 inches long. The rotor turns at a speed of 2175 RPM. The hammers shredded the wood chips until they passed through a screen with 1 inch diameter holes spaced 1.25 inches from center to center with 105 holes per square foot of screen.
The shredding process, followed by passage through the above-referenced screen, produced a mixture of wood particles of varying sizes. Representative samples were tested according to American Society of Testing Materials Test Method C136 using a Gilson Testmaster model TM-4 Sieve Shaker. The samples were shaken for seven minutes and the results were obtained by weighing retained gradient in each sieve. The results are given in Table 2.
TABLE 2______________________________________Particle Sizes of Chipped Wood Surfacing MaterialParticle size Percentage of sample______________________________________Particles passed through 5/8" sieve, 3%but retained on 1/2" sieveParticles passed through 1/2" sieve, 10%but retained on 3/8" sieveParticles passed through 3/8" sieve, 58%but retained on 1/4" sieveParticles passed through 1/4" sieve, 22%but retained on 1/8" sieveParticles passed through 1/8" sieve, 7%but retained on pan______________________________________
Random samples of the chipped wood were collected and tested to verify that the wood product had a critical height of at least 8 feet at an uncompressed depth of about 6 inches. The test procedure used is given in Example 2 below.
EXAMPLE 2
Test Method to Determine Critical Height Values
Representative samples of the surfacing material were tested according to Test Method F 355, Procedure C (metal headform) at various drop heights and test temperatures as set forth in Standard Specification for Impact Attenuation of Surface Systems Under and Around Playground Equipment, American Society for Testing and Materials (May 1991). This test method determined the maximum drop height at which the g-max did not exceed 200. The symbol "g" represents the acceleration into gravity at the earth's surface at sea level; g equals 32 ft/s or 9.8 m/s. The g-max is the multiple of g that represents a maximum deceleration experienced during an initial impact.
A six inch depth of the chipped wood surfacing material was placed in an 18"×18" box for the testing. A "C" size headform with an accelerometer (Endevco Accelerometer, Model 2215) mounted at its center was used in the tests. Impact acceleration data were obtained at drop heights of 10, 11 and 12 feet. The headform was oriented such that the impact surface was its crown.
The impact tests consisted of three drops at the same impact site at each of several different heights. The average of the second and third drop at each height yielded the recorded impact acceleration value. A new chipped wood sample was used for each set of drops. The impact test samples were tested at the three specific temperatures of 30° F., 72° F. and 120° F. (-1°, 23° and 49° C. respectively) after the required temperature equilibration. Table 3 gives the Critical Height values for the invention.
TABLE 3______________________________________Critical Heights (in feet) of Tested Chipped WoodSurfacing MaterialTemperature Thickness Drop height Impact acceleration(°F.) (inches) (feet) (g's)______________________________________30 6 10 175.130 6 11 171.230 6 12 172.272 6 10 151.872 6 11 177.672 6 12 201.2120 6 10 157.3120 6 11 170.9120 6 12 178.9______________________________________
The average of the second and third impact accelerations at an 11 foot drop height did not exceed 200 g's at the three test temperatures. Therefore, the invention has a critical height of 11 feet at a depth of 6 inches at all temperatures tested. This is at least four feet higher than the highest critical height of materials reported by the U.S. Consumer Products Safety Commission in its 1991 Handbook for Public Playground Safety.
The foregoing detailed description has been provided for a better understanding of the invention only and no unnecessary limitation should be understood therefrom as some modifications will be apparent to those skilled in the art without deviating from the spirit and scope of the appended claims. | Methods for producing a chipped wood surfacing material having unusually high shock absorbing capabilities are provided. The chipped wood is processed in order to give it a very high shock absorbing quality. This invention also relates to chipped wood having these unusually high shock absorbing characteristics. | 8 |
GOVERNMENT RIGHTS LEGEND
[0001] This invention was made with government support under contract OE-0000232 awarded by the U.S. Department of Energy. The government has certain rights in the invention.
BACKGROUND
[0002] 1. Field of Art
[0003] This description generally relates to energy storage, and particularly to energy storage using flywheels.
[0004] 2. Description of the Related Art
[0005] Many energy sources, particularly clean energy sources such as wind turbines and solar panels, generate energy that does not temporally match the load experienced. In much of the developed world, energy generation follows experienced load, such that energy is provided as needed. Under circumstances of high load, techniques such as the use of peaker generators and spinning and non-spinning reserves on thermal generators allow for generation that matches high and variable load. However, despite the availability of such techniques, there are often instances where energy storage is important for meeting energy load.
[0006] Currently existing energy storage systems all have drawbacks of one form or another. Size, price, storage efficiency, efficacy, and safety are all concerns when designing an energy storage system. Generally, smaller size, lower price, reduced loss in both inputting energy for storage and extracting it for distribution, reduced losses for continuous operation, and safe disposal are all preferred characteristics of energy storage systems.
[0007] A flywheel is one type of energy storage system that stores energy as rotational kinetic energy. A flywheel rotor is a weighted, rotationally symmetric mass that spins while physically coupled, directly or indirectly, to a motor/alternator that itself is electrically coupled to a converter, such as a back-to-back inverter system, constituting an AC-AC conversion subsystem. When power is received for storage, the rotor is driven, increasing the rotational speed of the flywheel rotor. When power is to be extracted, the flywheel rotor drives the motor/alternator. The faster a flywheel rotor can spin, the more energy it can store, but the more stress is induced on the rotor. Generally, the amount of stress a rotor is able to sustain while operating is a function of the design, materials, and processes used to make the rotor. Specifically, the amount of stress that can be sustained depends on a combination of the rotor material's yield strength, fracture toughness, maximal intrinsic defect size, cyclic fatigue characteristics, and the rotor's shape, among other factors. Generally, a flywheel's bearing and suspension subsystem is designed to minimize energy losses due to friction, and other loss sources.
[0008] Cost relative to the amount of energy that can be stored is of particular importance for a flywheel system. The cost of a flywheel system can be roughly divided into two portions, the cost of manufacturing the flywheel rotor, and the balance of system costs for supporting elements such as bearings, mountings, enclosure, etc. In the past, flywheel rotors have been very expensive to manufacture. As a result, flywheel systems have primarily been used in applications involving only seconds to minutes of energy storage, as it was simply too costly to either manufacture a single rotor that can store tens to hundreds of kWh of energy, or to use many individual rotors that are cost inefficient with respect to the balance of systems costs for the supporting elements used in conjunction with the rotors.
[0009] Some existing flywheel rotors are made of common, low alloy steels such as American Iron and Steel Institute (AISI) 4340 and AISI 4140. These steels have low costs and other desirable properties, however such rotors are limited to thin sections due to limitations in through-hardenability, which is required to achieve a useful yield strength and therefore that can handle a significant amount of stress. For example, although these rotor materials can achieve ultimate tensile strengths (UTSs) of 2 gigapascal (GPa), and fracture toughness of 40 megapascal square root meter (MPa·m 0.5 ), such rotors are limited to maximum cross-sectional thicknesses of 3-6 inches.
[0010] Other steel flywheel rotors are made with high-alloy steels such as maraging steels, Aermet steels, and some stainless steels. These flywheel rotors are able to sustain higher stresses throughout cross-sectional thicknesses greater than 6 inches. These rotors achieve these stresses without the need for multiple separate sections, but are cost prohibitive due to the high content of expensive alloying elements such as nickel and cobalt. Other modern flywheel rotors are made of carbon fiber and therefore allow for significantly higher working stresses, however the high cost of carbon fiber and the ancillary components needed to achieve the corresponding higher rotational speeds makes carbon fiber rotors prohibitively expensive, despite their high working strength-to-weight ratios.
SUMMARY
[0011] A high strength metal alloy flywheel rotor is described that offers improved kinetic energy storage at reduced cost. The flywheel rotor's performance is based in part on its material characteristics. In one embodiment it has a yield strength of at least 900 MPa, a fracture toughness of at least 70 MPa·m 0.5 , and a maximal intrinsic defect size of at most 2 millimeters (mm). These characteristics are consistent throughout its entirety.
[0012] In the same or a different embodiment, the rotor may be made of 300M vacuum-arc-remelting (VAR) steel that is through-hardened and tempered.
[0013] In various implementations, the rotor may also have additional characteristics beyond any of those described above. For example, the rotor may be formed with a diameter greater than its length (or thickness), or vice versa. The rotor may be rotationally symmetric. The rotor may be a monolithic shape without any bored holes. The rotor may include one or more journals protruding from the rotor allowing an external shaft to be physically attached to each journal. In one embodiment, the shaft may be attached using a shrink fit.
[0014] An exemplary method for manufacturing the rotor is also described.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a block diagram of a flywheel energy storage system according to one embodiment.
[0016] FIG. 2 is a cross sectional view of a flywheel rotor according to one embodiment.
[0017] FIG. 3 is a cross sectional view of a journal of a flywheel rotor according to one embodiment.
[0018] FIG. 4 is an exemplary process for manufacturing the flywheel rotor according to one embodiment.
[0019] The figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.
DETAILED DESCRIPTION
I. Flywheel Energy Storage System
[0020] FIG. 1 is a block diagram of a flywheel energy storage system 100 according to one embodiment. The energy storage system includes a flywheel rotor 130 , a motor/alternator 140 , a first inverter 150 , a capacitor 160 , a second inverter 170 , and an AC line 180 . Energy is drawn from, or delivered to, an AC line 180 , such as a conventional three-phase 60 Hz line. The first 150 and second 170 inverters as well as capacitor 160 illustrate an exemplary back-to-back converter system for converting the input alternating current into an alternating current acceptable to the motor/alternator 140 . The motor/alternator 140 converts between electrical and mechanical energy, so that energy can be stored in or drawn from the flywheel rotor 130 . The motor/alternator 140 is physically coupled to the flywheel rotor 130 either directly or indirectly using a shaft. The motor/alternator 140 is coupled to the remainder of the system 100 via wires or other electrical couplings. Generally, although only one of each component is shown, in practice a flywheel energy storage system 100 may include multiples of each individual component. FIG. 1 is one exemplary type of ac-to-ac conversion system. In general, the inventions described herein pertain to a broad range of ac-to-ac conversion topologies, as well as systems that interface directly to a direct current (dc) line. The latter are of especial relevance for dc microgrid and solar photovoltaic applications.
II. Flywheel Rotor Shape
[0021] FIG. 2 is a cross sectional view of a flywheel rotor 130 (or simply rotor) according to one embodiment. The rotor 130 is formed of a single mass of material. However, two different portions of the rotor 130 generally can be said to perform different functions. A primary rotational mass 230 makes up most of the mass of the rotor and stores the majority of the kinetic energy stored by the rotor. Two journals 212 extend perpendicularly from either side of the primary rotational mass and assist in coupling the rotor to separate shafts (not shown). Each of these portions is further described below. In some instances, the rotor may also include elements on its outer surface, for example discrete masses to provide centrifugal loading.
[0022] The rotor is generally rotationally symmetric, and thus the rotor can be described using a cylindrical coordinate system where the origin is through the center rotational axis of the rotor. In implementations including other elements on the outer surface, such as discrete masses, the rotor and the discrete mass elements are both uniformly distributed about the origin
[0023] To provide an example of scale, in one embodiment, the rotor 130 is between 36-72 inches in diameter, and weighs between 2-5 tons.
[0024] II.A Primary Rotational Mass
[0025] Beyond being rotationally symmetric, the primary rotational mass may be formed in a variety of different shapes, each designed to achieve specific performance goals. In one implementation, the primary rotational mass 230 of the rotor has a “fishtail” shape, when viewed in cross-section.
[0026] The fishtail shape helps ensure a nearly uniform distribution of stress throughout the primary rotational mass 230 due to rotational forces exerted on the rotor. The fishtail shape is an exemplary shape for optimizing rotor mass and material volume utilization, i.e. for optimizing the shape factor. Generally, the fishtail shape includes a center section and an adjoining peripheral mass. In the center section, the rotor is thicker closer to a first radius 202 near the center axis 226 , and continuously decreases in thickness out to a second radius 204 , away from the origin. In one embodiment, this central section is governed by a profile of the form:
[0000] t=he −βr 2 (1)
[0000] where t is the longitudinal thickness of the rotor, h is the central thickness, r is the distance away from the origin along the polar axis, and β is a constant.
[0027] Regarding the peripheral mass's shape, between the second radius 204 and a third radius 206 near the outer diameter 210 of the rotor, the primary rotational mass 230 continuously increases in thickness in the longitudinal axis. Between the third radius 206 and a fourth radius 208 , the rotor maintains a consistent thickness in the longitudinal axis for a short distance along the polar axis. The fourth radius 208 is located at or near the outer surface 210 of the rotor along the polar axis. Near the fourth radius 208 , the rotor's edges may be rounded or squared.
[0028] Regarding the relative proportions of the center section relative to the peripheral mass, the majority of the mass of the fishtail portion is located in the center section.
[0029] In the example illustrated in FIG. 2 , the outer surface 210 of the rotor 130 has a diameter that is greater than the widest thickness 228 of the fishtail portion of the rotor 130 . As will be further described below, any shape of rotor that allows the entirety of the rotor to be through-hardened is capable of achieving relatively high levels of working stress. Generally, rotors with diameters greater than their thickness rotate at slower speeds than their counterparts with thicknesses greater than their diameter. Slower rotational speeds reduce the operational requirements of the bearing assembly that allows the rotor to rotate, thereby reducing the overall cost of the flywheel system.
[0030] In another embodiment, rather than having the fishtail shape, the rotor instead has a cylindrical shape.
[0031] II.B Journals
[0032] Along the longitudinal axis (or center rotational axis) of the rotor, the rotor includes two journals 212 for attaching and detaching a shaft for transferring energy between the rotor and the bidirectional motor/alternator 140 . The journals 212 remove the need for a bore to couple the rotor to the shaft. A bore results in a doubling of hoop stress at the inner diameter of the bore. Such bores are often drilled into rotors after manufacturing of the rotor, or the rotors are deliberately designed and manufactured with such a hole in mind. In contrast, replacing a bore with the journals 212 allows stress to be more evenly distributed throughout the primary rotational mass, thereby avoiding a stress riser where the bore would otherwise be placed.
[0033] FIG. 3 is a cross sectional view of a journal 212 of the rotor according to one embodiment. Each journal 212 extends outward 218 from a mound 214 of increased thickness that itself extends outward from the origin of the center section of the primary rotational mass 230 . The mound 214 has a tapered shape that has a thickness greatest adjacent to the journal 212 , and which tapers gradually in thickness as radius increases. The gradually tapering shape of the mound 214 isolates the journal from experiencing a stress riser or peak stress at the point where the journal 212 adjoins the primary rotational mass 230 .
[0034] A fillet is present where the journal 212 and mound 214 are joined. The fillet avoids stress risers around the journal 212 . The journal's outer surface is substantially planar along the polar axis. The outer surface of journal 212 is narrower 220 than a connecting end 222 of the shaft 226 configured to attach to the journal 212 . The shaft then narrows 224 considerably for the majority of its length. Generally, the diameter 220 of the interference fit between the upper surface of the journal 212 and the shaft is greater than the diameter 224 of the shaft. Having a comparatively large diameter 220 for an interference fit is beneficial for further reducing stress risers inside the rotor 130 near the journal 212 , since only a relatively light interference fit is needed with such a large diameter. Further, the interference stresses induced in the journal region are generally compressive, and thus work to mitigate centrifugally induced stresses in the journal 212 . Thus, the combination of the tapering shape and wide diameter 220 of the journal 212 result in a mechanism for coupling with the shaft that minimizes the stress impact of the coupling on the rotor 130 as a whole.
[0035] In one embodiment, the shaft 226 is coupled to the journal 212 via a shrink fit. For example, the shaft can be heated prior to attachment to the journal 212 , causing the shaft to thermally expand. After heating, the journal 212 and shaft can be attached. The shaft is then allowed to cool, thereby thermally contracting to create an interference fit with the journal 212 . In another embodiment, an internal press fit may be used, with cooling of the shaft used to create the interference fit between the journal 212 and the shaft 226 . The shaft 226 may also be coupled to the journal 212 via a press fit, or with a central axially oriented retaining bolt if a hollow cylindrical shaft is used. These are examples of numerous alternatives for coupling the shaft 226 to the journal 212 .
[0036] As an example, in one embodiment the journal 212 has an outer diameter of approximately 4-6 inches, and protrudes outward from the mound approximately one inch. The shaft has a connecting end 222 outer diameter of 6-8 inches. Away from the connecting end, the shaft 226 has an outer diameter of 1-3 inches, which is narrower than the 4-6 inch outer diameter of the journal 212 .
[0037] The rotor, including the primary rotational mass 230 and journals 212 , is manufactured as a single piece of material, for example using the example materials and example process described below. Thus, the rotor has a single body construction where there are no welds, joints, seams, holes, or differences in construction between the primary rotational mass and journals 212 . However, also as further described below, different portions of the single body/single piece rotor may be subjected to different treatments and/or manufacturing processes to vary the properties of the rotor at different points. For example, the surface of the rotor may receive different treatments than the interior of the rotor.
III. Rotor Material Properties and Manufacturing
[0038] The performance of the rotor is based on several parameters of the materials that make up the rotor, as well as the manufacturing processes performed to convert the raw materials into the final state as they appear in the rotor. These parameters include the yield strength of the rotor, the fracture toughness of the rotor, the maximal intrinsic defect size (or maximum initial crack size) in the rotor, and the cyclic fatigue (or cyclic crack growth rate). The rotor may also be described in terms of other properties that are either known equivalents of these properties or that can be converted into/derived from these properties.
[0039] In one embodiment, the rotor has parameter values such that the yield strength σ yield of the rotor is greater than a first threshold, the fracture toughness σ fracture of the rotor is greater than a second threshold, and the maximal intrinsic defect size a intr is less than a threshold size. Defined in this way the rotor achieves significant performance in the working stress σ working it can endure over its operational lifetime. During the operation the rotor will always meet the following condition:
[0000] σ working <ασ yield (1)
[0000] where α is a parameter for derating between 0 and 1. Further, the rotor material is designed such that during the operational lifetime of the rotor, the cyclic crack growth, or growth of an initial crack present in the rotor during manufacturing as it grows towards the critical crack size, grows slowly enough to permit tens of thousands of complete stress cycles.
[0040] As a specific example, in one embodiment the rotor has a yield strength σ yield of at least 900 MPa, a fracture toughness σ fracture of at least 70 megapascal per square root meter (MPa·m 0.5 ), and a maximal intrinsic defect size that is 2 millimeters (mm) or smaller. In another embodiment, the rotor has a yield strength σ yield between 900 MPa and 2 GPa, inclusive, a fracture toughness σ fracture between 40 and 200 MPa·m 0.5 , inclusive, and a maximal intrinsic defect size between 0.05 mm and 2 mm, inclusive. In other embodiments, the rotor may have properties within any sub-range within the above described ranges. For example, in one embodiment, the rotor has a yield strength a σ yield of between 900-1000 MPa, 1000-1100 MPa, 1100-1200 MPa, 1200-1300 MPa, 1300-1400 MPa, 1400-1500 MPa, 1500-1600 MPa, 1600-1700 MPa, 1700-1800 MPa, 1800-1900 MPa, 1900-2000 MPa, or any combination of sub-ranges thereof. In the same or a different embodiment, the rotor has a fracture toughness σ fracture of between 40-50 MPa·m 0.5 , 50-60 MPa·m 0.5 , 60-70 MPa·m 0.5 , 70-80 MPa·m 0.5 , 80-90 MPa·m 0.5 , 90-100 MPa·m 0.5 , 100-110 MPa·m 0.5 , 110-120 MPa·m 0.5 , 120-130 MPa·m 0.5 , 130-140 MPa·m 0.5 , 140-150 MPa·m 0.5 , 150-160 MPa·m 0.5 , 160-170 MPa·m 0.5 , 170-180 MPa·m 0.5 , 180-190 MPa·m 0.5 , 190-200 MPa·m 0.5 , or any combination of sub-ranges thereof. In the same or a different embodiment, the rotor has a maximal intrinsic defect size of between 0.5-0.6 mm, 0.6-0.7 mm, 0.7-0.8 mm, 0.8-0.9 mm, 0.9-1.0 mm, 1.0-1.1 mm. 1.1-1.2 mm, 1.2-1.3 mm, 1.3-1.4 mm, 1.4-1.5 mm, 1.5-1.6 mm, 1.6-1.7 mm, 1.7-1.8 mm, 1.8-1.9 mm, 1.9-2.0 mm, or any combination of sub-ranges thereof.
[0041] A rotor that meets the above exemplary thresholds can be made of 300M steel. 300M steel is described by Aerospace Material Standard (AMS) Society of Automotive Engineers (SAE) 6257 (referred to simply as SAE-6257). 300M steel has a proportional chemical composition of 1.6% Silicon (Si), 0.82% Chromium (Cr), 1.8% Nickel (Ni), 0.40% Molybdenum (Mo), 0.08% Vanadium (V), and a range of 0.40-0.44% Carbon (C), with remainder being Iron (Fe). 300M steel has a relatively low cost, and thus is advantageous for reducing the cost of a flywheel energy storage system including a rotor made of this material. The V and Si are alloying elements that offer improved hardenability and allow thick-section rotors to be made that are up to 14″ thick and entirely through-hardened, for example in the fishtail shape as described above.
[0042] However, mere specification of 300M steel alone is insufficient to ensure the parameters specified above. Additional manufacturing steps are used to improve the performance of the rotor. These steps include refining, multi-step forging, heat treatments, surface treatments, and machining.
[0043] The 300M steel is refined using a refinement process such as vacuum-arc-remelting (“VAR”), electro-slag-remelting (“ESR”), or vacuum induction melting (VIM). These processes help remove defects larger than the desired maximal intrinsic defect size. In contrast, if the 300M steel were instead melted in open air, it would tend to have defects larger than this desired maximal intrinsic defect size such as inclusions or other impurities. VAR refinement helps ensure that the maximal intrinsic defect size is 2 mm or smaller.
[0044] Multi-step forging introduces directional grains into the rotor. Generally, grain orientation is determined based on the forging process used. A single step forging process may be insufficient to ensure the presence of consistent directional grains throughout the entirety of the rotor. Performing multiple forging steps helps ensures consistent grain orientation throughout the entirety of the rotor. Controlling grain orientation also has the added benefit of shaping and orienting any inclusions present in the rotor.
[0045] Generally, heat treatments are used to increase yield strength and hardness of steel. In a heat treatment, the steel is heated (or austenetized) into austenite. The time and temperature of the heating in part defines the grain size of the rotor. The austenite is then rapidly cooled (or quenched). The quenching converts the austenite into one of several other material phases of steel, such as pearlite and martensite. Due to the physics of heat transfer, not all depths within the steel will cool at the same rate, meaning that shallower depths of the steel will often quench into a significant proportion of martensite (e.g., greater than 50% martensite), whereas deeper depths of the steel may quench into a significant proportion of pearlite or other material phases, with only a minority of the steel quenching into martensite (e.g., less than 50% martensite). The proportions of various material phases a steel quenches into is governed by the material's transition curve (referred to as a TTT curve). Martensite, specifically, is desirable for use in a rotor because it has very high yield strength and also very high hardness. A piece of steel is said to be through-hardened when at every thickness the steel contains at least 50% martensite.
[0046] In one embodiment, VAR 300M steel is used in the rotor because it is possible to through-harden the 300M steel to depths of 8-14 inches, making it very useful for forming a rotor of sufficient size to store a significant amount of kinetic energy. Particularly, the Si and V alloying elements in 300M delay the formation of pearlite during quenching in favor of the transition to martensite, resulting in increased through-hardness at significant depths within the steel. In a VAR 300M rotor, through-hardening allows the rotor to achieve a yield strength σ yield of up to 2 GPa.
[0047] Quenched steels have a drawback of having a low fracture toughness. Consequently, the quenching step can be followed by a tempering step. Tempering maintains the steel at a temperature lower than austenetizing temperature (e.g., 600-1200 Fahrenheit (F)) for a period of time (e.g., several hours) before cooling slowly back to room temperature. At the expense of some yield strength σ yield , tempering significantly improves fracture toughness, and eliminates residual internal stresses. In a VAR 300M rotor, tempering allows the rotor to achieve a fracture toughness σ fracture of at least 70 MPa·m 0.5 while also maintaining a σ yield of over 900 MPa.
[0048] Surface treatments protect the surface of the rotor. Several different surface treatments may be used. A first is shot peening, where compressive stress is imparted to the surface of the rotor to harden it. A second is nitrogen and/or carbon treatments that similarly increase hardness as well as the yield strength of the rotor's surface. Other surface treatments may also be used.
[0049] One advantage of a rotor constructed as described above is that a significantly larger rotor, one capable of storing tens to hundreds of kWh of energy, can be manufactured at low cost relative to other potentially conceivable processes. Further, the total cost of a flywheel system incorporating such a rotor is also lowered relative to existing flywheel systems that use many smaller rotors. This is due to the fact that using a large rotor reduces the need for multiple rotors and their associated supporting elements. For example, it is much less expensive for a flywheel system to use a larger bearing to support a larger rotor versus using many smaller rotors each using their own smaller bearings. Further, a single monolithic rotor is also generally more economical than a rotor assembled from a stack of separate rotor components.
IV. Method of Manufacture
[0050] FIG. 4 is an exemplary process for manufacturing a rotor according to one embodiment. In the example of FIG. 4 , elements are alloyed 401 to manufacture steel with the desired material composition. For example, if 300M is to be used, Si, Cr, Ni, Mo, V, C, and Fe are alloyed together. The alloyed elements are then refined 403 to remove large defects. Continuing with the example above, the VAR process may be used to refine the 300M alloy. The refined alloy is then forged 405 to near net shape using a multi-step process to orient grain size and direction. A heat treatment is applied 407 to through-harden the forged rotor material to improve yield strength. Tempering 409 is then performed to improve fracture toughness. The rotor material may then be machined 411 to form the rotor into the desired shape.
[0051] Upon reading this disclosure, those of skill in the art will appreciate still additional alternative structural and functional designs through the disclosed principles herein. Thus, while particular embodiments and applications have been illustrated and described, it is to be understood that the disclosed embodiments are not limited to the precise construction and components disclosed herein. Various modifications, changes and variations, which will be apparent to those skilled in the art, may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the spirit and scope defined in the appended claims. | A solid steel flywheel rotor having improved material properties offers improved energy storage at reduced cost. A process for manufacturing the rotor is also provided. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a U.S. national stage application of a PCT application PCT/RU2008/000578 filed on 28 Aug. 2008, published as WO/2009/038498, whose disclosure is incorporated herein in its entirety by reference, which PCT application claims priority of a Russian Federation application RU2007134923 filed on 19 Sep. 2007.
FIELD OF THE INVENTION
The invention relates to methods and devices for spraying liquid during production processes requiring a uniform dispersion mixture, in particular in internal combustion engines requiring a fine fuel-air mixture, in the chemical industry for apparatuses for rinsing gas with liquid that require a uniform coarse-dispersion mixture for reducing the drop entrainment of a rinsing liquid.
BACKGROUND OF THE INVENTION
Many devices are known for spraying liquid during production processes that use the method of pneumatic spraying and belong to jet devices. Jet devices are those where a process of exchanging kinetic energy from one flow to another takes place by immediate mixing. Despite a variety of jet device constructions the following basic elements can be noted: an active nozzle, a mixing chamber, a diffusor, an input part of the throat for passive flow, which is usually made in the form of a confusor (New reference book for chemist and technologist. Processes and apparatuses for chemical technology, part 1, St. Peterburg, ANO NPO “Professional”, 2004, on page 405). A disadvantage of such devices is the inhomogeneity of the resulting mixture, i.e. diameter of particles vary widely and the particle size distribution is very non-uniform. For example, there are not many large particles but they have the most part of fuel mass (Morozov K. A. Matuhin L. N. Feeding systems of modern petrol engines, Manual, MADI, M., 1988, on page 7).
One device is known from inventor's certificate of USSR N2797783 of 1981. The device comprises air-supply and fluid-supply systems, a spray chamber with input and output pipes, sprayers and a liquid collector. Sprayers are chordally installed in the spray chamber. Disadvantages of this device are high aerodynamic resistance, large size and high material consumption, and impossibility of production of a homogeneous coarse-dispersion mixture. The following cause these disadvantages. The cylindrical part of the spray chamber, where sprayers are chordally installed, enforces rotary moving gas inside the chamber. It results in high aerodynamic resistance in comparison with laminar unidirectional gas flow. The spray chamber has to measure a certain size to set up rotary movement of a gas flow. It is necessary to enlarge the diameter of the cylindrical part in order to reduce aerodynamic resistance. The large size of the device predetermines its high material consumption. When a gas flow is moving in a rotary manner, particles of all sizes except the smallest ones are collected on the internal side of the chamber. The smallest particles are held in the rotary gas flow, not for their low sedimentation velocity, which is determined by the relation of aerodynamic forces to mass of a particle, but due to mechanism of Brownian movements acting, as it is known, on particles of sizes that do not exceed many times the sizes of gas molecules.
One more device is known from inventor's certificate of USSR N2246200 of 1969 (point 2). The device comprises a case, a water sprayer and a water collector connected to the water sprayer. The water sprayer is made in the form of a set of pipes with perforated sides. Pipes are placed in the case and are parallel to the air flow direction. A disadvantage of this device is inhomogeneity of the resulting mixture. The following cause this disadvantage. A liquid goes out of the end faces and many apertures in the pipe sides. A liquid is broken down into particles of various sizes that are carried away so it forms a set of spray cones. Sectors with prevailing large, medium and small particles can be found in every spray cone except spray cones from the pipe end faces. Many spray cones overlay one upon another in an irregular way and form a flow of a liquid spray where particles of various sizes are distributed uniformly. As a result, large, medium and small particles are collected in a nonselective way on the sides of the case. The collected particles form, when accumulated, a liquid that is returned for re-spraying.
The most similar to technical essence of the inventive method is the method for spraying liquid (prototype), described in the book Morozov K. A. Matuhin L. N. Feeding systems of modern petrol engines, Manual, MADI, M., 1988, on page 7. The method consists in injecting liquid at an angle into a gas flow. A disadvantage of the method is inhomogeneity of the resulting mixture that increases fuel consumption in internal combustion engines because of incomplete combustion of large particles of fuel.
The most similar to technical essence of the inventive device is the device for spraying liquid (prototype), described in the book Dmitrievskij A. V., Kamenev V. F. Automobile carburetors. M: Mechanical engineering, 1990, on pages 76-77. The device comprises a body with an internal channel, which is made in the form of a Venturi pipe, and a spray nozzle placed in the narrow part of the internal channel at an angle to the gas flow direction. A disadvantage of this device is inhomogeneity of the resulting mixture that increases fuel consumption in internal combustion engines because of incomplete combustion of large particles of fuel.
SUMMARY AND BRIEF DESCRIPTION OF THE INVENTION
The present invention solves the problem of homogeneous enhancement for a mixture, which is produced in spraying liquid by injection of a liquid into a gas flow. In order to solve the problem, spraying is carried out by injection of a liquid into a gas flow at an angle to the gas flow direction but not parallel. The gas flow breaks down a liquid flow into particles of various sizes and carries them away so it forms a spray cone. The trajectories of large particles deviate from a spray nozzle further than the trajectories of small particles do. It is due to an action of the field of aerodynamic forces and the initial momentum of a liquid, which goes out of the nozzle at an angle to the gas flow direction and is broken down into particles. It brings to the non-uniform particle size distribution in the spray cone, i.e. the different sectors with prevailing large, medium and small particles are formed. The illustration of dividing the spray cone into sectors with particles of various sizes is given in FIG. 3 .
Particles of specified sizes in the resulting spray cone are selected (removed), i.e. particles of such sizes that are undesirable for whatever reason. If large and medium particles in the spray cone are removed then small particles remain. If medium and small particles are removed then large particles remain. If medium particles are removed then large and small particles remain. Selection (removal) of particles is carried out as follows. A collector for particles of a liquid spray is installed at some distance from the spray nozzle. The collector is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes. It is necessary and sufficient for selection (removal) of particles of specified sizes that the collector collects all particles of a liquid spray. In addition, the collector should be placed in the appropriate sectors of the spray cone. Particles, which are collected by the collector for particles of a liquid spray, form, when accumulated, a liquid that is returned for re-spraying (recirculating). The processes of spraying liquid and selecting (removing) particles of specified sizes in the spray cone are carried out in one section of a laminar gas flow, which has no turns and rotations.
The technical result is the production of a mixture that is more homogenous in terms of the particle sizes due to removing particles of specified sizes in the spray cone where specified sizes depend on a variant of the method usage or the purpose of the device.
The inventive concept consists in departure from known technical decisions where at first a liquid is sprayed and a flow with large and small particles uniformly distributed is obtained. Further, particles of specified sizes in a flow are separated and removed. Instead of doing so, liquid is sprayed in such a manner that spatial separation of particles of various sizes takes place in the very spray cone at the same time as spraying liquid. In this case removing particles of specified sizes reduces to removing particles of all sizes in the appropriate sectors of the spray cone. Mathematical modeling proves the efficiency of such approach to solving the problem of homogeneous enhancement for spraying liquid. It shows that the determinant influence for the whole trajectory has only the initial phase of the trajectory where particles appear from a liquid flow and have minimum velocity. The less velocity a particle has the more easily its trajectory can be changed. As a particle of a liquid accelerates, it becomes more difficult to change its trajectory.
According to the invention, the technical result for the method (production of a mixture that is more homogeneous in terms of particle sizes) is achieved due to spraying liquid by injection of a liquid through a spray nozzle at an angle to the gas flow direction. In addition, a process of selection of (removal of) particles of specified sizes is carried out in a spray cone simultaneously with the process of spraying. The process of selection is carried out by a collector for particles of a liquid spray that is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of a liquid spray in those sectors of the spray cone that are appropriate to particle sizes. The processes of spraying liquid and selection of (removal of) particles of specified sizes are carried out in one section of a laminar gas flow, which has no turns and rotations. Particles of a liquid spray, which are collected by the collector, form, when accumulated, a liquid that is returned for re-spraying.
The common element with the known method for spraying liquid is spraying liquid by injection through a spray nozzle at an angle to the gas flow direction.
The new elements, which differentiate the inventive method from the prototype, are the following:
the process of selection of (removal of) particles of specified sizes is carried out in the spray cone simultaneously with the process of spraying;
the process of selection (removal) is carried out by the collector for particles of a liquid spray that is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of a liquid spray in those sectors of the spray cone that are appropriate to particle sizes;
the processes of spraying liquid and selection of (removal of) particles of specified sizes are carried out in one section of a laminar gas flow, which has no turns and rotations;
particles of a liquid spray, which are collected by the collector, form, when accumulated, a liquid that is returned for re-spraying.
According to the invention, the technical result for the device of variant No. 1 (production of a mixture that is more homogeneous in terms of particle sizes) is achieved due to a device comprising: a body with an internal channel, a spray nozzle, which is placed at an angle to the gas flow direction and is connected to a liquid feed pipe, a collector for particles of a liquid spray, which is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes. The internal channel is made to be able to provide a laminar gas flow, which has no turns and rotations, in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray. The collector for particles of a liquid spray is connected to a pipe for returning a liquid for re-spraying.
The common elements with the device known from prototype are:
the body with the internal channel;
the spray nozzle, which is placed at an angle to the gas flow direction and is connected to the liquid feed pipe.
The new elements, which differentiate the inventive device from the prototype, are:
the collector for particles of a liquid spray which is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes;
the internal channel, which is made to be able to provide a laminar gas flow, which has no turns and rotations, in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray;
the collector for particles of a liquid spray, which is connected to the pipe for returning a liquid for re-spraying.
According to the invention, the technical result for the device of variant No. 2 (production of a mixture that is more homogeneous in terms of particle sizes) is achieved due to a device comprising: a body with an internal channel, a spray nozzle, which is placed at an angle to the gas flow direction and is connected to a liquid feed pipe, a collector for particles of a liquid spray, which is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes. The internal channel is made to be able to provide a laminar gas flow, which has no turns and rotations, in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray. The collector for particles of a liquid spray is connected via a pipe for returning a liquid for re-spraying to an additional spray nozzle, which is made and placed to be able to overlay the appropriate sectors of the spray cones regarding those sectors of both spray cones where particles are collected.
The common elements with the device known from prototype are:
the body with the internal channel;
the spray nozzle, which is placed at an angle to the gas flow direction and connected to the liquid feed pipe.
The new elements, which differentiate the inventive device from the prototype, are:
the collector for particles of a liquid spray, which is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes;
the internal channel, which is made to be able to provide a laminar gas flow, which has no turns and rotations, in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray;
the collector for particles of a liquid spray is connected via the pipe for returning a liquid for re-spraying to the additional spray nozzle, which is made and placed to be able to overlay the appropriate sectors of the spray cones regarding those sectors of the both spray cones where particles are collected by the collector for a liquid spray.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the device of variant No. 1 .
FIG. 2 shows the device of variant No. 2 .
FIG. 3 is an illustration of dividing the spray cone into sectors with particles of various sizes.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the invention may be susceptible to embodiment in different forms, there are shown in the drawings, and will be described in detail herein, specific embodiments of the present invention, with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention, and is not intended to limit the invention to that as illustrated and described herein.
Therefore, according to variant No. 1 of the present invention, the inventive device comprises: a body ( 1 ) with an internal channel ( 2 ) capable of creating a laminar unidirectional gas flow having a direction, said internal channel ( 2 ) having an intake end for entering said gas flow, and a discharge end for exiting said gas flow; a liquid feed pipe ( 6 ) for supplying said liquid into said internal channel ( 2 ), said liquid feed pipe ( 6 ) having an end furnished with a spray nozzle ( 3 ) placed within said internal channel ( 2 ) at a predetermined angle to said direction of the gas flow, said spray nozzle ( 3 ) producing a spray conical distribution of liquid particles of different sizes, wherein a specific sector of the spray conical distribution corresponds to a specific particle size; a collector ( 4 ) for collecting particles of the liquid of a specified size, said collector ( 4 ) is disposed in a predetermined sector of said spray conical distribution with respect to the predetermined size of particles at the second end of said internal channel ( 2 ); and a returning pipe ( 5 ) having a first end connected to said collector ( 4 ) and a second end substantially associated with said spray nozzle ( 3 ) for re-spraying the liquid.
Additionally, for the inventive device of variant No. 1 , there is proposed a method for selective-recirculating spraying a liquid comprising the steps of: —providing a body ( 1 ) with an internal channel ( 2 ) capable of creating a laminar unidirectional gas flow having a direction, said internal channel ( 2 ) having an intake end for entering said gas flow, and a discharge end for exiting said gas flow; a liquid feed pipe ( 6 ) for supplying said liquid into said internal channel ( 2 ), said liquid feed pipe ( 6 ) having an end furnished with a spray nozzle ( 3 ) placed within said internal channel ( 2 ) at a predetermined angle to said direction of the gas flow, said spray nozzle ( 3 ) producing a spray conical distribution of liquid particles of different sizes, wherein a specific sector of the spray conical distribution corresponds to a specific particle size; a collector ( 4 ) for collecting particles of the liquid of a predetermined size, said collector ( 4 ) is disposed in a predetermined sector of said spray conical distribution with respect to the predetermined size of particles at the second end of said internal channel ( 2 ); a returning pipe ( 5 ) having a first end connected to said collector ( 4 ) and a second end substantially associated with said spray nozzle ( 3 ) for re-spraying the liquid; —inputting said gas flow into said intake end of the internal channel ( 2 ); —inputting said liquid via said spray nozzle into the internal channel ( 2 ); —collecting particles of the liquid of said predetermined size; and
—returning the collected particles of the liquid of said predetermined size to said spray nozzle ( 3 ) for re-spraying.
According to variant No. 2 of the present invention, the inventive device comprises: a body ( 1 ) with an internal channel ( 2 ) capable of creating a laminar unidirectional gas flow having a direction, said internal channel ( 2 ) having an intake end for entering said gas flow, and a discharge end for exiting said gas flow; a liquid feed pipe ( 6 ) for supplying said liquid into said internal channel ( 2 ), said liquid feed pipe ( 6 ) having an end furnished with a first spray nozzle ( 3 ) placed within said internal channel ( 2 ) at a predetermined angle to said direction of the gas flow; a second spray nozzle ( 7 ) placed within said internal channel ( 2 ) at a predetermined angle to said direction of the gas flow, thereby producing a spray conical distribution of liquid particles of different sizes, wherein a specific sector of the spray conical distribution corresponds to a specific particle size; a collector ( 4 ) for collecting particles of the liquid of a predetermined size, said collector ( 4 ) is disposed in a predetermined sector of said spray conical distribution with respect to the predetermined size of particles at the second end of said internal channel ( 2 ); a returning pipe ( 5 ) having a first end connected to said collector ( 4 ) and a second end connected to said second spray nozzle ( 7 ) for re-spraying the liquid, thereby providing for a conical distribution of liquid particles of the predetermined size; wherein said second spray nozzle ( 7 ) is placed to be capable of overlaying said conical distribution of liquid particles of the predetermined size on said conical distribution of liquid particles of different sizes.
Additionally, for the inventive device of variant No. 2 , there is proposed a method for selective-recirculating spraying a liquid comprising the steps of: —providing the device of variant No. 2 , described above; —inputting said gas flow into said intake end of the internal channel ( 2 ); —inputting said liquid via said spray nozzle ( 3 ) into the internal channel ( 2 ); —collecting particles of the liquid of said predetermined size; and—returning the collected particles of the liquid of said predetermined size to said second spray nozzle ( 7 ) for re-spraying.
The inventive method is carried out as follows. A liquid is injected through a spray nozzle at an angle of 90° to the gas flow direction. The gas flow breaks down the liquid flow, which goes out of the spray nozzle, into particles of various sizes and carries them away so that it forms a spray cone. The trajectories of large particles deviate from the spray nozzle further than the trajectories of small particles do. It is due to an action of the field of aerodynamic forces and the initial momentum of a liquid, which goes out of the nozzle at an angle to the gas flow direction, and is broken down into particles. It brings to the non-uniform particle size distribution in the spray cone and different sectors with prevailing large, medium and small particles being formed. The illustration of dividing the spray cone into sectors with particles of various sizes is given in FIG. 3 . The process of selection of (removal of) particles of specified sizes in the spray cone is carried out simultaneously with the process of spraying. The process of selection (removal) is carried out by a collector for particles of a liquid spray that is installed at some distance from the spray nozzle and it is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particles of specified sizes. The processes of spraying liquid and selection (removal) of particles of specified sizes in the spray cone are carried out in one section of a laminar unidirectional gas flow. Particles of a liquid spray, which are collected by the collector, form, when accumulated, a liquid, which is returned for re-spraying. After selection (removal) of particles of specified sizes in the spray cone, it is characterized as more homogeneous in terms of particle sizes.
The spray nozzle is made in the form of the end of a pipe. Other embodiments of the spray nozzle are possible. It is necessary and sufficient to realize that the function of the spray nozzle is to direct a liquid flow. This function in combination with other elements provides the possibility to achieve the technical result.
The angle between the spray nozzle and the gas flow direction is 90°. Other values of the angle are possible. It is necessary and sufficient that a liquid flow is not parallel to the gas flow direction. It provides the non-uniform distribution of large and small particles in the spray cone. The angle in combination with other elements provides the possibility to achieve the technical result.
The collector for particles of a liquid spray is made in the form of the end of a pipe. The collector is installed at some distance from the spray nozzle. It is made and placed to be able to collect particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. There is some distance between the end of the pipe and the spray nozzle. Some distance is necessary for starting the process of breaking down a liquid flow into particles. The end of the pipe is made and placed in those sectors of the spray cone that are appropriate to particles of specified sizes. It is possible to embody the collector for particles of a liquid spray in the form of socket pipes, rings, plates, parts of the internal channel and other embodiments. It is necessary and sufficient to realize that the function of the collector for particles of a liquid spray is to select (remove) particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. This function in combination with other elements provides the possibility to achieve the technical result.
The processes of spraying liquid and selecting particles of specified sizes in the spray cone are carried out in one section of a laminar unidirectional gas flow. This condition of passing processes is achieved due to the arrangement of the spray nozzle and the collector for particles in the rectilinear channel. Other known methods are possible. It is necessary and sufficient to provide just the condition but not a particular method or material means. This condition in combination with other elements provides the possibility to achieve the technical result.
According to variant No. 1 , the inventive device comprises a body 1 with an internal channel 2 , made in the form of a Venturi pipe. There is a spray nozzle 3 in the narrow part of the internal channel 2 . The spray nozzle is placed at an angle of about 90° to the gas flow direction and it is connected to a liquid feed pipe 6 . A collector 4 for particles of a liquid is installed at some distance from the spray nozzle 3 . It is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes. The collector 4 is connected to a pipe for returning a liquid for re-spraying 5 .
The device of variant No. 1 works as follows. A gas flow goes through the internal channel 2 where its rate increases and depression takes place. A liquid goes through the feed pipe 6 to the spray nozzle 3 and goes out of it under the influence of this depression. The gas flow breaks down the liquid flow, which goes out of spray nozzle 3 , into particles of various sizes and carries them away so it forms a spray cone. The trajectories of large particles deviate from a spray nozzle further than the trajectories of small particles do. It is due to an action of the field of aerodynamic forces and the initial momentum of a liquid, which goes out of the nozzle at an angle to the gas flow direction and is broken down into particles. The non-uniformly sized particles are distributed in the spray cone, i.e. the different sectors with prevailing large, medium and small particles are formed. The illustration of dividing the spray cone into sectors with particles of various sizes is given in FIG. 3 . Particles of specified sizes are collected in the appropriate sectors of the spray cone by the collector 4 . The collector 4 is installed at a predetermined distance from the spray nozzle 3 . This distance can be chosen by the designer taking into account a particular device to be designed according to the present invention. It is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particles of specified sizes. Particles of the liquid spray are collected in the collector 4 . They form, when accumulated, a liquid, which is drawn under the influence of aerodynamic forces to the pipe for returning the liquid for re-spraying 5 . It means re-spraying by the spray nozzle 3 . Particular detail is not specified as it is easy to do and it is not essential for this invention. After collecting (removing) particles of the specified sizes in the spray cone, it is characterized as more homogeneous in terms of particle sizes.
The spray nozzle 3 is made in the form of the end of a pipe 6 . Other embodiments of the spray nozzle 3 are possible. It is necessary and sufficient to realize that the function of the spray nozzle is to direct a liquid flow. This function in combination with other elements provides the possibility to achieve the technical result.
The angle between the spray nozzle 3 and the gas flow direction is about 90°. Other values of the angle are possible. It is necessary and sufficient that the liquid flow be not parallel to the gas flow direction. It provides the non-uniform distribution of large and small particles in the spray cone. The angle in combination with other elements provides the possibility to achieve the technical result.
The internal channel 2 is made in the form of a Venturi pipe. This form of the internal channel 2 gives the possibility of providing a laminar unidirectional gas flow in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray. Secondly, it makes depression in the narrow part of the channel 2 and provides moving a liquid to the spray nozzle 3 . It is possible to embody the internal channel 2 in the form of pipes having round, square and other section, in the form of confusor, diffusor and other forms, which provides a laminar unidirectional gas flow in the section that starts before the spray nozzle 3 and ends at the collector 4 . It is necessary and sufficient to realize that the function of the internal channel 2 is to provide a laminar unidirectional gas flow in the section that starts before the spray nozzle 3 and ends at the collector 4 . This function in combination with other elements provides the possibility to achieve the technical result.
The collector 4 is made in the form of the end of the pipe 5 (as shown on FIG. 1 ). The collector 4 is installed at a predetermined distance from the spray nozzle 3 . This distance can be chosen by the designer taking into account a particular device to be designed according to the present invention. It is made and placed to be able to collect particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. There is some distance between the end of the pipe 5 (i.e. the collector 4 ) and the spray nozzle 3 (as shown on FIG. 1 ). Some distance is necessary for starting the process of breaking down a liquid flow into particles. The end of the pipe 5 is made and placed in those sectors of the spray cone that are appropriate to particles of specified sizes. It is possible to embody the collector 4 in the form of socket pipes, rings, plates, parts of the internal channel 2 and other embodiments. It is necessary and sufficient to realize that the function of the collector for particles of a liquid spray 4 is to select (remove) particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. This function in combination with other elements provides the possibility to achieve the technical result.
According to variant No. 2 ( FIG. 2 ) the inventive device comprises a body 1 with an internal channel 2 , made in the form of a Venturi pipe. There is a spray nozzle 3 in the narrow part of the internal channel 2 . The spray nozzle is placed at an angle of about 90° to the gas flow direction and it is connected to a liquid feed pipe 6 . A collector 4 is installed at a predetermined distance from the spray nozzle 3 . This distance can be chosen by the designer taking into account a particular device to be designed according to the present invention. It is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particle sizes. The collector 4 is connected via a pipe 5 for returning a liquid for re-spraying 5 to an additional spray nozzle 7 that is placed at an angle of 90° to the gas flow direction predeterminedly close to the spray nozzle 3 . This distance can also be chosen by the designer taking into account a particular device to be designed according to the present invention.
The device of variant No. 2 works as follows. A gas flow moves through the internal channel 2 where its rate increases and depression takes place. A liquid is drawn through the feed pipe 6 to the spray nozzle 3 and exits it under the influence of this depression. The gas flow breaks down the liquid flow, which is sprinkled from the spray nozzle 3 , being broken down into particles of various sizes and carries them away, thereby forming a spray cone. The trajectories of large particles deviate from the spray nozzle further than the trajectories of small particles do. It is due to an action of the field of aerodynamic forces and the initial momentum of the liquid, which exits of the nozzle at an angle to the gas flow direction and is broken down into particles. The non-uniformly sized particles are distributed in the spray cone, i.e. the different sectors with prevailing large, medium and small particles are formed. The illustration of dividing the spray cone into sectors with particles of various sizes is shown in FIG. 3 . Particles of specified sizes are collected in the appropriate sectors of the spray cone by the collector 4 . The collector 4 is installed at a predetermined distance from the spray nozzle 3 . This distance can be chosen by the designer taking into account a particular device to be designed according to the present invention. It is made and placed to be able to collect particles of specified sizes in those sectors of the spray cone that are appropriate to particles of specified sizes. Particles of the liquid spray are collected in the collector 4 . They form, when accumulated, a liquid, which is drawn under the influence of aerodynamic forces to the pipe 5 for returning the liquid for re-spraying, and further moves to the additional spray nozzle 7 (as shown on FIG. 2 ). The additional spray nozzle 7 forms its spray cone in such a manner that the appropriate sectors of both spray cones from the spray nozzle 3 and the additional spray nozzle 7 are coincident. After selecting (removing) the particles of specified sizes from the spray cone, it is characterized as more homogeneous in terms of particle sizes.
The spray nozzle 3 is made in the form of the end of a pipe 6 . Other embodiments of the spray nozzle 3 are possible. It is necessary and sufficient to realize that the function of the spray nozzle is to direct a liquid flow. This function in combination with other elements provides the possibility to achieve the technical result.
The angle between the spray nozzle 3 and the gas flow direction is about 90°. Other values of the angle are possible. It is necessary and sufficient that a liquid flow is not parallel to the gas flow direction. It provides the non-uniform distribution of large and small particles in the spray cone. The angle in combination with other elements provides the possibility to achieve the technical result.
The internal channel 2 is made in the form of a Venturi pipe. This form of the internal channel 2 gives the possibility of providing a laminar unidirectional gas flow in the section that starts before the spray nozzle and ends at the collector for particles of a liquid spray. Secondly, it makes depression in the narrow part of the channel 2 and provides moving a liquid to the spray nozzle 3 . It is possible to embody the internal channel 2 in the form of pipes having round, square and other section, in the form of confusor, diffusor and other forms, which provide a laminar unidirectional gas flow in the section that starts before the spray nozzle 3 and ends at the collector 4 . It is necessary and sufficient to realize that the function of the internal channel 2 is to provide a laminar unidirectional gas flow in the section which starts before the spray nozzle 3 and ends at the collector for particles of a liquid spray 4 . This function in combination with other elements provides the possibility to achieve the technical result.
The collector 4 is represented by the end of the pipe 5 . The collector 4 is installed at a predetermined distance from the spray nozzle 3 . This distance can be chosen by the designer taking into account a particular device to be designed according to the present invention. It is made and placed to be able to collect particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. There is some distance between the end of the pipe 5 and the spray nozzle 3 . Some distance is necessary for starting the process of breaking down a liquid flow into particles. The end of the pipe 5 is made and placed in those sectors of the spray cone that are appropriate to particles of specified sizes. It is possible to embody the collector 4 in the form of socket pipes, rings, plates, parts of the internal channel 2 and other embodiments. It is necessary and sufficient to realize that the function of the collector for particles of a liquid spray 4 is to select (remove) particles of a liquid spray in those sectors of the spray cone that are appropriate to particles of specified sizes. This function in combination with other elements provides the possibility to achieve the technical result.
The additional spray nozzle 7 is represented by the end of the pipe 5 . It is made and placed to be able to overlay the appropriate sectors of the spray cones regarding those sectors of both spray cones where particles of specified sizes are collected by the collector 4 . The end of the pipe 5 (i.e. the nozzle 7 ) is made and placed in such a manner that the appropriate sectors of both spray cones are coincident. Other embodiments and placement arrangements of the additional spray nozzle 7 are possible. It is necessary and sufficient to realize that the function of the additional spray nozzle 7 is to spray a liquid with the possibility of overlaying the appropriate sectors of the spray cones regarding those sectors of both spray cones where particles of specified sizes are collected by the collector 4 . | The invention relates to methods and devices for spraying liquid during production processes requiring a uniform dispersion mixture, in particular in internal combustion engines requiring a fine fuel-air mixture, in the chemical industry for apparatuses for rinsing gas with liquid, which require a uniform coarse-dispersion mixture for reducing the drop entrainment of a rinsing liquid. The inventive method consists in collecting, during the liquid spraying, which is carried out by injecting a liquid at an angle to a gas flow, particles in those sectors of the spray cone that are appropriate to particles of specified sizes. The liquid spraying and collecting processes are carried out at one section of a laminar unidirectional gas flow. The collected particles form, when accumulated, a liquid that is returned for re-spraying. The inventive device comprises a body ( 1 ) with an internal channel ( 2 ) for providing a laminar unidirectional gas flow, a spray nozzle ( 3 ) which is placed at an angle to the gas flow direction and is connected to a liquid feed pipe ( 6 ) and a collector for particles ( 4 ) which is made and placed in such a manner that it is able to collect particles in those sectors of the spray cone that are appropriate to particles of specified sizes. In the first variant, the collector is connected to a pipe for returning the liquid for re-spraying ( 5 ), and in the second variant, the collector is connected to an additional spray nozzle ( 7 ) made in the internal channel of the body. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a skiving head and process for skiving cylinders, cylinder tubes and the like, using a skiving head. The skiving head has a number of skiving blades arranged radially and floating in the skiving head.
[0003] 2. The Prior Art
[0004] Such processes and skiving heads are known, for example, from German Patent Nos. DE 22 23 969 and DE 27 23 622. They serve in the machining, and in particular the fine machining, of cylindrical hole walls such as are found in hydraulic cylinders and cylinder tubes. Such hole walls are fine-machined most economically by skiving and roller burnishing. Initial materials are generally drawn precision steel tubes or soft steel tubes with prepared by boring out, with a small machining allowance of approx. 0.3 to 1 mm in diameter. These tubes feature straightness errors incurred by manufacturing, which are not detrimental to the purpose of the tubes and which therefore do not need to be corrected by the skiving process.
[0005] However, the surface of the hole wall must be peeled and roller burnished over the full surface even with cambered cylinders. Under the given conditions, the skiving blade must follow the macroform of the tube at almost constant chip depth. To achieve this, skiving blades arranged in floating fashion have proved their worth, such as described in DE 27 23 622 or DE 25 18 170 already referred to. The skiving head in this situation is capable of free radial movement in two planes in relation to the tool, and the skiving blade(s) is/are in addition capable of radial movement.
[0006] The known arrangement of the skiving blades guarantees the self-centering of the blades due to the passive cutting forces of both cutting edges even when the skiving head is not rotating centrically due to the effect of outside forces. A disadvantage with this arrangement, however, is that the skiving blades, equipped with two mutually-opposed cutting edges, do not necessarily create a circular hole. Rather, such skiving blades can carry out a radially floating movement during the rotation of the skiving head, and in this situation create a hole cross-section which deviates from the circular. This movement can be incurred due to an error in roundness already present in the tube, or a slight disturbance in the balance of force, possibly due to fluctuating passive cutting force with regular intentional chip breakage, and may build up and propagate over the entire machining length.
[0007] The hole, measured between two mutually-opposed points, may indeed feature a constant diameter, but the interior enveloping circle may be smaller and the outer enveloping circle larger than the skiving diameter measured in the two-point process. In this situation “polygons” may be formed, with 3, 5, 7 or more “corners”. These errors in roundness may lead to problems with the assembly of pistons and seals. The error in roundness frequently runs over the length of the tube with an angle offset from one tool revolution to the next, resulting in a helical contour of the cylinder, which as a rule is regarded as a quality deficiency.
[0008] Tools without floating blades are also known. These include the reamers such as described in German Patent Nos. DE 19 62 181 B, DE 16 52 790 A, DE 73 21 746 U, and in U.S. Pat. No. 2,638,020. The reamer blades are all only capable of adjustment jointly, by the same dimension in relation to the basic structure of the tool, and are therefore not installed in a radially floating manner. Reamers are conceptually designed to produce holes with the smallest possible errors in straightness. Continuation of machining is therefore effected in continuation of the previous direction of the hole bore. If the previous bore was cambered, it is expected of the reamers that they will eliminate this cambering as much as possible.
[0009] Cylinder tubes are manufactured from drawn precision steel tubes with a length of up to 10 meters. Due to the chipless manufacturing process employed hitherto, these tubes feature errors in straightness of up to 2 mm/m. At the same time, however, to save material and money, work is carried out with machining allowances of less than 1 mm in the diameter. This means that insufficient machining allowance is provided to make a straight hole out of the cambered hole. To achieve this with the camber indicated heretofore, a machining allowance of at least 4 mm in the diameter would be required. Tools which, like the reamers described earlier, are designed for the manufacture of the straightest possible holes, would remove a great deal of material to chips, and in return would leave other places unmachined. Accordingly, the requirement is imposed on a skiving head for the skiving of cylinders, cylinder tubes, and the like, for the skiving tool to follow the macroform of the hole during machining, and accordingly repeats the existing errors in straightness. The reamers do not meet this requirement.
SUMMARY OF THE INVENTION
[0010] It is therefore an object of the invention to provide a skiving head and process for skiving which will allow for errors in roundness to be eliminated as far as possible, and to prevent the occurrence of helical waves.
[0011] This object is accomplished by a skiving head with skiving blades arranged radially floating in the skiving head, in which at least three skiving blades are provided for. With such an arrangement, both the requirement for self-centering of the skiving blade set as well as circular skiving geometry with constant cutting depth will be fulfilled.
[0012] In addition to this, the invention has the great advantage that due to the three skiving blades, the skiving capacity can be increased in relation to known skiving heads with only two skiving blades.
[0013] In a preferred embodiment of the invention, in which the skiving head features a central axis, adjacent skiving blades seen in the direction of the central axis of the skiving head are arranged at similar angular distances to one another. This guarantees the greatest possible centering probability in every rotation position of the skiving head. The angular distance would accordingly be 120 degrees with three skiving blades, 90 degrees with four skiving blades, 72 degrees with five skiving blades, and 60 degrees with six skiving blades. These angles may vary slightly from sector to sector if appropriate in order to avoid shatter marks.
[0014] In another preferred embodiment of the invention, in which the skiving head has a central axis and each skiving blade featured at least one cutting edge, there are at least three cutting edges of different skiving blades arranged rotationally symmetrically to the central axis of the skiving head. For each one cutting edge of a skiving blade, corresponding cutting edges of up to at least two other skiving blades are provided for, so that corresponding points of corresponding cutting edges define a plane which runs perpendicular to the central axis of the skiving head. Because the central axis of the skiving head is the main axis of rotation during the operation of the head, this arrangement likewise has a positive effect on the centering of the skiving head in the hole which is to be peeled out.
[0015] The skiving capacity can be further increased by each skiving blade featuring at least two cutting edges.
[0016] In a particularly advantageous embodiment of the invention, all skiving blades are supported directly or indirectly by a common conical or pyramidal body arranged in a displaceable manner in the skiving head, and can be displaced via this body radially to the skiving head. In this situation, depending on the design of the skiving head, the body may also take the form of a cone or truncated cone as well as of a pyramid or truncated pyramid. The term pyramid is not restricted here in the conventional sense to such regular polyhedra as have a square base and four congruent isosceles triangles as side surfaces, but is to be understood in the meaning of the geometric definition, and in particular may have a base with as many sides as skiving blades are provided.
[0017] Both a conical and pyramidal body allow, by simple displacement of the body alone the central axis of the skiving head, for the skiving blades to be pressed radially outwards. In this way, the corresponding skiving diameter can be adjusted in a particularly simple manner.
[0018] In this situation, the conical or pyramidal body is preferably arranged floating in the skiving head. There is a means for the changeable determination of a first relative position of the conical or pyramidal body relative to the skiving blades, so that the conical or pyramidal body can be subjected to preliminary tension by appropriate spring media into the first relative position. This first relative position is as a rule the operating position of the skiving head, in which the skiving blades are therefore adjusted to the desired skiving diameter.
[0019] In order to be able to withdraw the skiving head from the peeled-out body easily and without the occurrence of markings, the conical or pyramidal body can be designed so that it is capable of being moved against the preliminary tension by the use of an outer force, and a hydraulic force in particular, into a second relative position relative to the skiving blades. This second relative position corresponds to the withdrawn position of the skiving blades, so that this is accordingly no longer located close to the surface to be peeled out and the skiving head is capable of being moved and positioned in the body which is to be peeled out.
[0020] In order to guarantee that the skiving blades are always in contact, directly or indirectly, in the conical or pyramidal body, and therefore, by changing the relative position of conical or pyramidal body and skiving blades, follow the desired setting of the skiving diameter, there are spring media which subject the skiving blades to preliminary tension against the conical or pyramidal body. These second spring media are arranged so that their direction of effect does not run through the center of the tool.
[0021] To prevent the tilting of the skiving blades, they are guided in guides, of which the length to breadth ratio is greater than 1.5, and preferably greater than 2. The ratio of length to breadth may even reach 4 or 5 in order to achieve good guidance effect. In this context, the term length means the extension of the guide in the radial direction, while the term breadth means the extension of the guide in the axial direction.
[0022] The invention also comprises a process for skiving out a cylinder, cylinder tube, or the like by means of a skiving head introduced into the body which is to be peeled out with a central axis and a number of skiving blades. The skiving head has at least three skiving blades radially movable relative to the central axis of the skiving head.
[0023] In a preferred embodiment of the process, whereby each skiving blade features at least one cutting edge, the radial distance between the cutting edges and the central axis of the skiving head, and therefore the skiving diameter, is adjusted via a conical or pyramidal body arranged so as to be capable of movement in the skiving head.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.
[0025] In the drawings, wherein similar reference characters denote similar elements throughout the several views:
[0026] [0026]FIG. 1 shows a skiving head according to the invention in a partially sectional side view along the central axis;
[0027] [0027]FIG. 1 a is a detailed view of the skiving head shown in FIG. 1, in the area of the blades;
[0028] [0028]FIG. 2 is a partially sectional view of the skiving head according to FIG. 1, seen in the direction of the central axis;
[0029] [0029]FIG. 3 illustrates the effect of the centering forces during the operation of the skiving head; and
[0030] [0030]FIG. 4 shows an alternative embodiment of a skiving head in a partial sectional side view along the central axis.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] Referring now in detail to the drawings, FIGS. 1 to 3 show a skiving head designated in its entirety by 9 , in which a total of three skiving blades 10 are arranged in a radially displaceable manner in a cylindrical housing 11 .
[0032] Each skiving blade 10 has two cutting edges 3 and 3 ′. Skiving blades 10 are guided in guides 10 ′ with large length-to-breadth ratios, which prevent the tilting of the skiving blades. In the embodiment shown, this guide is more than three times longer than wide, and to be precise even more than five times. There are guides 25 that are always arranged between the skiving blades.
[0033] As indicated in FIG. 2 with only one blade, each skiving blade 10 is pressed by spring media, in this case in the form of pressure spring elements 13 , radially inwards against a conical body which adjusts the skiving diameter. The conical body is in the form of a truncated cone 12 . For this purpose each skiving blade 10 features a mounting 13 ′ for one pressure spring element 13 in each case. Each skiving blade 10 is subjected to preliminary tension by a pressure spring element 13 in the direction onto the cone, as indicated by the arrows 13 ″ in FIGS. 2 and 3, of which only a few have been provided with reference indicators for the sake of easier overview. Truncated cone 12 is thereby stored swimmingly in the skiving head with the degrees of freedom 12 ′ and 12 ″
[0034] Pressure spring elements 13 , during the skiving process and in the introduced state, in which the skiving blades are located in a withdrawn position seen in a radial direction towards the central axis, provide for sustained contact of the blades 10 with the truncated cone 12 .
[0035] To determine a first relative position of the truncated cone 12 and skiving blades 10 , a screw-spacer element combination 15 is provided for. Spring media, in this case in the form of a coil spring 14 , tension the truncated cone into this relative position, which corresponds to the operating position in which the tool is ready to carry out skiving.
[0036] By the application of a force in the direction of arrow 16 , for example by means of an inherently known hydraulic system, not shown here in any greater detail, the truncated cone 12 can be displaced along the common central axis 16 ′ of skiving head 9 and truncated cone 12 against the preliminary tension of the spring 14 , as a result of which the skiving blades 10 move radially inwards into a withdrawn position.
[0037] Truncated cone 12 is arranged floating in skiving head 9 . As shown in FIG. 3, an error in straightness of a cylinder tube which is to be peeled out by the dimension 19 means a change in the hole contour 17 and the hole axis 17 a by the dimension 19 into the position 18 or 18 a respectively. This leads to an increase in the passive cutting forces of all the cutting edges operating in the drawing above the center, and at the same time to a decrease in the lower positions in the drawing. The truncated cone 12 reacts to this with a radial downwards movement 20 by the dimension 19 . In this way, the entire blade set centers itself, while maintaining the envelope geometry onto the new tube center. Accordingly, the requirements for the self centering of the skiving blade set, circular skiving geometry, and consistent cutting depth are fulfilled. The compensation movement is effected under the rotation of the skiving tool or continuously with the tool at a standstill and with the tool rotating, and can be carried out in any desired direction depending on the tube camber.
[0038] [0038]FIG. 4 shows an embodiment in which the force 16 ″ engages on the broad side of the truncated cone 12 ″′ and the coil spring 14 ′ engages via the screw-spacer combination 15 ′ on the smaller diameter of the truncated cone 12 ″′. This arrangement also incurs a displacement of the cutting edges 3 ″ and the skiving blade 10 ″ relative to the housing 11 ′.
[0039] Numerous divergences and further embodiments are possible within the framework of the concept of the invention, which relate, for example, to the number and arrangement of the skiving blades and cutting edges. It is possible, for example, for skiving out large diameters, to use skiving heads which feature more than the three skiving blades described above. Central to the invention in any event is the fact that there are more than two skiving blades, which clearly reduces the probability of occurrence of unintentional radial oscillation.
[0040] Accordingly, while only a few embodiments of the present invention have been shown and described, it is obvious that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention. | In order to eliminate errors in roundness and the occurrence of helical waves, a skiving head is provided with at least three skiving blades arranged in a radially displaceable manner in the skiving head. With this skiving head, both the requirement for self-centering of the skiving blade set as well as the requirement for circular skiving geometry with consistent cutting depth are fulfilled. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of copending International Application No. PCT/DE99/04012, filed Dec. 16, 1999, which designated the United States and was not published in English.
BACKGROUND OF THE INVENTION
[0002] Field of the Invention
[0003] The invention relates to a method and a device for determining the absolute angle of rotation of an object that is rotating about an approximately horizontal rotational axis, in particular a motor vehicle rotating about its longitudinal axis.
[0004] In modern occupant protection systems for motor vehicles, the task arises, in the event of a rollover about the longitudinal axis, of detecting the absolute angle of rotation of the vehicle in order to be able to correctly time a decision to fire a restraining device or other protection devices.
[0005] Issued European Patent No. EP 0 430 813 B1 discloses a safety system for motor vehicles that operates with four sensors. A rate of rotation sensor detects the angular velocity of the rotation of the vehicle about its longitudinal axis. Three acceleration sensors detect the longitudinal acceleration, the transverse acceleration, and the vertical acceleration of the vehicle. The output signal of the rate of rotation sensor is integrated, and if it is above a threshold value, is fed to an OR element so that a pyrotechnic firing device is tripped. The integration of the output signal from the rate of rotation sensor is not performed continuously, but only during a time window that is determined by the output signals from the acceleration sensors.
[0006] Published European Patent Application EP 0 934 855 A1 discloses a method and a device for tripping a rollover protection device in which longitudinal, lateral, and vertical vehicle accelerations as well as rollover and pitching rates—supplied by corresponding sensors—are subjected to time averaging. The time-averaged signals are subjected to an expanded Kalman filter. Output variables of the Kalman filter is the current rollover angle and the current pitch angle of the vehicle. All five input variables must be fully utilized in order to calculate each of these variables.
SUMMARY OF THE INVENTION
[0007] It is accordingly an object of the invention to provide a method and a device for determining the absolute angle of rotation of an object that is rotating about an approximately horizontal rotational axis, in particular a motor vehicle rotating about its longitudinal axis. Using the method and the device it is possible to determine the absolute angle of rotation quickly and accurately in conjunction with simple executability and simple design.
[0008] With the foregoing and other objects in view there is provided, in accordance with the invention, a method for determining an absolute rotational angle of an object that is rotating about an approximately horizontal rotational axis. The method includes steps of: determining a change in a rotational angle of the object occurring during a time interval; determining an acceleration component acting in a direction of a vertical axis of the object; determining a change, occurring during the time interval, in the acceleration component acting in the direction of the vertical axis of the object; and calculating the absolute rotational angle of the object from the change in the rotational angle and the change in the acceleration component acting in the direction of the vertical axis of the object.
[0009] In accordance with an added mode of the invention, the object is a motor vehicle rotating about a longitudinal axis thereof.
[0010] In accordance with an additional mode of the invention, the method includes: calculating the absolute rotational angle using the following formula:
α=( m )(Δ a z −Δa z 0 ),
[0011] where α is the absolute rotational angle, and
[0012] where m=C3/Δα, Δa z 0 =1−cos (Δα), C3 is a constant, Δα is the change in the rotational angle, and Δa z is the change in the acceleration component.
[0013] With the foregoing and other objects in view there is provided, in accordance with the invention, a device for determining an absolute angle of rotation of an object that is rotating about an approximately horizontal rotational axis. The device includes: a rate of rotation sensor for detecting an angular velocity of the object rotating about the rotational axis; an integrator for integrating the angular velocity and for determining a change in an angle of rotation; an acceleration sensor for detecting an acceleration component acting in a direction of a vertical axis of the object; a difference element for determining a change, accompanying the change in the angle of rotation, in the acceleration component acting in the direction of the vertical axis; and an arithmetic unit for calculating the absolute angle of rotation of the object from the change in the angle of rotation and the change in the acceleration component.
[0014] In accordance with an added feature of the invention, there is provided a high-pass filter configured between the rate of rotation sensor and the integrator.
[0015] In accordance with an additional feature of the invention, there is provided a high-pass filter configured between the acceleration sensor and the difference element.
[0016] In accordance with another feature of the invention, the arithmetic unit operates using the following formula:
α=( m )(Δ a z −Δa z 0 ),
[0017] where α is the absolute rotational angle, and
[0018] where m=C3/Δα, Δa z 0 =1−cos(Δα), C3 is a constant, Δα is the change in the rotational angle, and Δa z is the change in the acceleration component.
[0019] In accordance with a further feature of the invention, the arithmetic unit is programmed to perform the following steps:
[0020] A) detect ω(t) and a z (t), where t=time, ω(t) is the angular velocity, and a z (t) is the acceleration component;
[0021] B) determine
Δα ( T ) = ∫ 0 T ω ( t ) t ,
[0022] where T=a time interval, and calculate Δa z =a z (T)−a z (0);
[0023] C1) if Δα<C1, where C1 is a constant, then proceed to step A),
[0024] C2) if Δa z >C2, where C2 is a constant, then proceed to step A; and
[0025] D) calculate:
α= m ·(Δ a z −Δa z 0 ), where
[0026] m=C3/Δα, Δa z 0 =1−cos (Δα)
[0027] and C3 is a constant.
[0028] According to the invention, the change, caused by gravity, in the acceleration in the direction of the vertical axis of the vehicle, and the angle by which the vehicle rotates around its longitudinal axis are determined within a time interval. The two items of information can be used to calculate the absolute angle of rotation of the vehicle, that is to say its absolute rotary position. Because only differences of signals are considered, absolute sensor values are not necessary, and so no expensive, high-stability acceleration sensors need to be used. Instead, sensors of simple design can be used.
[0029] The invention can advantageously be applied wherever the aim is to determine the absolute angular position of an object that is rotating, in a gravity field, around a rotational axis inclined to the direction of gravity. The invention takes advantage of the fact that the gravity component or acceleration component changes in accordance with a sinusoidal or cosinusoidal function in the direction of an axis that is fixed in the object and that is rotating relative to the direction of gravity during the rotation, so that it is possible from the change in the gravity component and in the angle of rotation of the object to reach a conclusion on the absolute angle of rotation and the rotary position of the latter in a fixed coordinate system. The invention is particularly suitable for use in motor vehicles for the purpose of expediently tripping safety devices that protect against the consequences of a rollover.
[0030] Other features which are considered as characteristic for the invention are set forth in the appended claims.
[0031] Although the invention is illustrated and described herein as embodied in a method and device for determining the absolute angle of rotation of an object that is rotating about an approximately horizontal rotational axis, 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.
[0032] 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
[0033] [0033]FIG. 1 shows a motor vehicle with sensors arranged therein;
[0034] [0034]FIG. 2 illustrates the fundamental physical principle of a rate of rotation sensor;
[0035] [0035]FIG. 3 illustrates the fundamental physical principle of an acceleration sensor for detecting the acceleration component that acts in the direction of the vertical axis of the object and that is a function of the absolute angle of rotation of the object;
[0036] [0036]FIG. 4 shows a block diagram of an inventive device;
[0037] [0037]FIG. 5 shows curves for explaining the calculation of the absolute angle of rotation; and
[0038] [0038]FIG. 6 shows curves for explaining the accuracy of the calculation carried out in accordance with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a motor vehicle having a rate of rotation sensor 2 and an acceleration sensor 4 that are connected to a control unit 6 . The control unit 6 is connected, in turn, to occupant protection devices 8 , for example, seat belt pretensioners, head airbags, or else, in particular in the case of convertibles, rollover bars that can be extended from the seat frames or body parts, etc. The efficiency of the system will be explained below in the case of a rollover in which the vehicle rotates about its longitudinal axis x. In the position z of the vertical axis of the vehicle (normal position of the vehicle on horizontal ground), the vertical axis z of the vehicle corresponds to the fixed vertical. After a rotation about the longitudinal axis by the angle α, the vertical axis z′ of the vehicle forms an angle α with the fixed vertical direction. The angle α is designated below as the absolute angle of rotation.
[0040] [0040]FIG. 2 indicates the fundamental physical principle of a rate of rotation sensor: an inertial member 12 , for example a ball, is located inside a housing 10 . When the housing 10 connected to the motor vehicle rotates suddenly at the rate of rotation or angular velocity of ω, the inertial member 12 remains at rest, and so the relative rotation between the inertial member 12 and the housing 10 can be detected and output as an output signal ω proportional to the rate of rotation, for example, in the form of pulses per time unit. A rotation by a predetermined angular amount corresponds to each pulse.
[0041] [0041]FIG. 3 shows the fundamental principle of an acceleration sensor 4 . Inside a housing 14 is arranged an inertial member 16 that is pushed upward by a spring 18 in accordance with FIG. 3. In the illustrated vertical position of the housing 14 , the spring force counteracts the total acceleration due to gravity or the weight of the inertial member 16 . When the housing 14 is rotated from the vertical by the angle a, the force of the spring 18 now counteracts gravity only with a component (m)(g)cosα, where m is the mass of the inertial member 16 , g is the end acceleration due to gravity, and α is the absolute angle of rotation. It is therefore possible to generate an output signal that is proportional to the absolute angle of rotation α by detecting the force active in the direction of the movement of the inertial member 16 . By appropriately damping the moveability of the inertial member 16 , the acceleration sensor 4 can be constructed in such a way that essentially only the absolute rotary position α is detected and accelerations of the vehicle itself that occur, for example, upon driving over obstacles, are largely suppressed. It goes without saying that such peak accelerations can also be suppressed by appropriately filtering the output signal.
[0042] [0042]FIG. 4 shows a block diagram of the inventive device. The rate of rotation sensor 2 is connected to an integrator 22 via a high-pass filter 20 . The acceleration sensor 4 is connected to a difference element 26 via a high pass filter 24 .
[0043] The integrator 22 and the difference element 26 are connected to an arithmetic unit 28 whose output signal is fed to a unit 30 that determines whether an output signal is generated at its output 32 in order to trip appropriate occupant protection devices. This determination is made in accordance with algorithms prestored in unit 30 and by possibly evaluating further input signals. It goes without saying that a plurality of algorithms can be stored in the unit 30 , and that the unit 30 can generate a plurality of output signals that can be used to individually trip individual safety devices. The safety devices can be ignited, tripped magnetically or activated in some other way.
[0044] The units 22 , 26 , 28 and 30 are advantageously accommodated in the control unit 6 which, if appropriate, can also hold the filters 20 and 24 . Alternatively the filters 20 and 24 can also be integrated directly in the sensors 2 and 4 .
[0045] The construction of the microprocessor-controlled control unit 6 is known per se and will therefore not be explained.
[0046] The functioning of the device shown in FIG. 4 will be explained below using the variables that are detected by the sensors. The further processing of these variables in conjunction with temporal control of the microprocessor (not illustrated) will also be explained:
[0047] A). The rate of rotation sensor 2 determines the time-dependent angular velocity ω(t) of the time-dependent rotation of the vehicle about its longitudinal axis. After filtering the output signal from the rate of rotation sensor 2 in the high-pass filter 20 , an output signal ω(t) is available that is largely free from the zero drifting of the rate of rotation sensor 2 .
[0048] Similarly, the acceleration sensor 4 generates a signal that corresponds to the absolute angle of rotation α. This signal is very inaccurate, and after being subjected to high-pass filtering, is available as a time-dependent acceleration a z (t) acting in the direction of the vertical axis of the vehicle.
[0049] B). The change in the angle of rotation is determined in the integrator 22 within the time interval T as:
Δα ( T ) = ∫ 0 T ω ( t ) t .
[0050] Alternatively, the integrator 22 can count pulses sent directly from the rate of rotation sensor, during a time interval, so that a value corresponding to the angle of rotation during the time interval is available if each pulse corresponds to a predetermined angle of rotation and if counting is performed up or down depending on the direction of rotation.
[0051] The change in the acceleration component a z within the time interval T is calculated in the difference element 26 as:
Δ a z ( T )= a z ( T )− a z (0)
[0052] Zero fluctuations and drifting of the acceleration sensor 4 are largely compensated by this subtraction.
[0053] C). If Δα is smaller than a constant C1, or if Δa z is larger than a constant C2, this means that the signals are not suitable for subsequent calculation of the absolute angle of rotation, since the angular rotation was too small or the change in the acceleration component was too large, and this permits external interference to be deduced so that the system returns to the above-named stage A. If both named conditions are not fulfilled, the system goes over to the next stage D.
[0054] D). The absolute value is calculated by using the following formulas:
α= m· (Δ a z −Δa z 0 ), where
[0055] m=C3/Δα, Δa z 0 =1−cos (Δα).
[0056] The above steps are each repeated with updated data, in which offsets from the sensors are compensated. If, for example, the angle α changes by 10° and the acceleration in the Z-direction changes by 0.1 g, the absolute value of α is determined as 29.5°. The accurate calculation would yield 30°. The value, calculated using the above method, of the absolute angle of rotation α is fed to the unit 30 and is available there for further evaluation as a sufficiently accurate value of the absolute angle of rotation α that specifies the rotary position of the vehicle relative to the vertical.
[0057] The formulas named in the above steps are derived below:
[0058] As explained using FIG. 3, a z =(g)cosα. It follows from this that:
Δ a z =( g )(cosα−cosα 0 )
and
α−α 0 =Δα=∫ωdt.
[0059] The combination of the above-named formulas yields:
cos α = Δ a z g + cos ( α - Δα ) ( 1 )
[0060] Solving formula 1 for α yields:
α = ± Arccos [ ± 1 4 · ( Sin ( Δα / 2 ) ) 2 · ( ± Δ a z ∓ Δ a z · Cos ( Δα ) + ( 2 - Δ a z 2 - 2 · Cos ( Δα ) ) · ( sin ( Δα ) ) 2 ) ]
[0061] Limiting the absolute angle of rotation to the interval from −90° to +90° yields the image shown in FIG. 5.
[0062] The curves in the diagram shown in FIG. 5 show the absolute angle of rotation a as a function of Δa z /g for various values of Δα as parameters.
[0063] As can be seen, a linear approximation can be undertaken for Δa z near the zero Δa z 0 or large values of Δα. Δa z 0 can be calculated using formula 1 and is:
Δα z 0 =1−cosΔα. (2)
[0064] (It may be pointed out that this formula can be approximated effectively by a parabola if it is impossible to calculate the cosine function because of a low arithmetic capability of the system.)
[0065] The gradient near the zero can likewise be calculated as:
( ∂ α ∂ Δ a z ) Δ a z 0 = 1 - cos ( 2 · Δα ) + 2 ( sin ( Δα ) ) 2 2 ( sin ( Δα ) ) 2
[0066] A good approximation is a hyperbola:
( ∂ α ∂ Δ a z ) Δ a z 0 = 3477 deg 2 / g Δα
[0067] In summary, it emerges from the above that the absolute angle of rotation α can be calculated with high accuracy and limited arithmetic capabiliy from the output signals from the two sensors 2 and 4 (FIG. 4).
[0068] Discussion of Errors;
[0069] The measurement of the input variables Δα and Δ z can be performed only within a specific error bandwidth. For example, let the rate of rotation sensor have a tolerance band of ±5%. Moreover, even an ideal acceleration sensor for detecting accelerations in the z-direction is theoretically unable to distinguish between external accelerations and gravity. However, a distinction may be drawn by using an algorithm that, for example, monitors the stability of the acceleration signal over time, and if appropriate, correlates it with other variables. However, it is necessary to bear this source of error in mind.
[0070] The curves in FIG. 6 show the error Fα in the absolute angle of rotation α in degrees as a function of the absolute angle of rotation α for various sensor tolerances. A change of 10° in the angle was assumed for the illustration. If the calculation begins with an initial absolute angle of rotation of 50° and ends with an absolute angle of rotation of 60°, the approximation in the case of perfect sensors would then lead to the result of 55° (instead of 60°). A 5% inaccuracy of the two sensors would lead to 61°, and a 10% error would lead to an absolute angle of rotation of 67°.
[0071] It goes without saying that the system described can be modified in multifarious ways. For example, the acceleration sensor fixed in the vehicle can also be aligned in a way other than parallel to the vertical axis of the vehicle. | A method for determining an absolute rotational angle of an object that is rotating about an approximately horizontal rotational axis, includes steps of: determining a change in a rotational angle of the object occurring during a time interval; determining an acceleration component acting in a direction of a vertical axis of the object; determining a change, occurring during the time interval, in the acceleration component acting in the direction of the vertical axis of the object; and calculating the absolute rotational angle of the object from the change in the rotational angle and the change in the acceleration component acting in the direction of the vertical axis of the object. A device constructed to perform the method does not necessarily require expensive, high-stability acceleration sensors. Sensors of a simple design can be used instead. | 1 |
FIELD OF THE INVENTION
The present invention generally relates to skeletal muscle stimulation, and more particularly, it relates to an intramuscular lead system having an improved electrode end for easier insertion.
BACKGROUND OF THE INVENTION
Skeletal muscle tissue is often used to provide cardiac assistance. Such systems which utilize skeletal muscle tissue may be seen in U.S. Pat. No. 4,411,268, issued to Cox, and U.S. Pat. No. 4,813,952, issued to A. Khalafalla, and U.S. Pat. No. 4,735,205 all assigned to Medtronic, Inc., and incorporated herein by reference.
Such systems use a patient's own muscle tissue in conjunction with a implantable pulse generator to provide cardiac assistance. In comparison to presently available cardiac assist systems using wholly artificial structures, systems using a patient's skeletal muscle are extremely compact and energy efficient. Such cardiac assist systems, however, are not without limitations. One problem presented by the use of skeletal muscle power for cardiac assistance is the application of electrical stimulation signals to cause skeletal muscle contraction.
The electrical connection between an implantable pulse generator and the desired skeletal muscle is accomplished through a lead. Generally speaking a lead is a wire insulated along its length and having an electrode at one end and connectable to a pulse generator at its other end. Through a lead then electrical signal may be communicated to and from skeletal muscle tissue.
The earliest skeletal muscle powered cardiac assist systems used screw-in type leads for skeletal muscle stimulation. A major improvement to these leads is found in the use of steroid eluting pacing leads. U.S. Pat. No. 4,711,251 issued to Stokes, and assigned to Medtronic, Inc. teaches the use of an endocardial pacing lead having steroid drug embedded in the distal tip. This embedded steroid drug treats the heart tissue immediately in contact with the pacing electrode. U.S. Pat. Nos. 4,506,680; 4,577,642; and 4,606,118 teach similar endocardial leads, all of which treat the electrode contact area with asteroid. United States Statutory Invention Registration No. H356 discloses an endocardial pacing lead suitable for epicardial insertion which elutes a steroid drug from the electrode.
A further improvement in intramuscular lead technology arose with the adaptation of heart wire technology for chronic pacing use. Typically such leads are constructed as follows: A connector assembly has a coiled connector attached thereto. The coiled connector is insulated along a part of its length while a suture runs throughout its inner lumen, from the connector assembly to an end. At the end of the suture a helical portion is formed, and a needle is attached to the end of the suture. The suture material is treated with asteroid drug, such as a glucocorticosteroid, along its entire length. Additional drugs which may be imbedded within strand include antibiotics. Upon chronic implantation, the steroid drug is eluted from the suture material, thus treating possible tissue inflammation or damage caused by the implantation procedure or subsequent irritation.
One drawback to such a lead as presently configured is found at the conductor coil-suture interface. In designs presently in use the conductor coils are attached to the end of suture by a crimp sleeve. In such a manner a tip electrode is formed. Because the suture is used to pull the electrode coil through muscle tissue during implantation, crimp sleeve used to form tip electrode, which has a larger diameter than either suture or electrode coil, creates friction. Such friction creates difficulties to the physician during implantation. For this reason a flexible, specifically designed lead having a relatively slender dimension at the conductor coil-suture interface is desired.
SUMMARY OF THE INVENTION
Briefly, the above and further objects and features of the present invention are realized by providing a new and improved intramuscular lead. The lead can be used to electrically stimulate muscle tissue that are configured for a cardiac assist system powered by surgically modified skeletal muscle tissue. The skeletal muscle is either wrapped about the heart itself, or about an auxiliary pumping chamber attached to the aorta. Electrical stimulation is supplied via the intramuscular lead to cause contraction of the skeletal muscle in synchrony with the natural or artificially paced heart rate and timed to obtain the desired hemodynamic effect. The improved lead has an electrode which is embedded in the skeletal muscle. The electrode is attached to a suture through a tapered section of electrode coil. Through such a taper the electrode coil and suture are firmly joined.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other options, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with accompanying drawings, wherein:
FIG. 1 is an schematic view of one configuration of a cardiac assist system;
FIG. 2 is a plan view of a chronically implantable stimulation lead according to the present invention;
FIG. 3 is an enlarged partial view of the coiled conductor-suture interface of chronically implantable stimulation lead according to the prior art;
FIG. 4 is an enlarged partial view of the coiled conductor-suture interface of a chronically implantable stimulation lead according to the present invention; and
FIG. 5 is a schematic view of the chronically implantable lead according to the present invention positioned in a skeletal muscle.
FIG. 6 is an enlarged partial view of the coiled conductor-suture interface of an alternate embodiment for a chronically implantable stimulation lead according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Cardiac assist systems utilizing electrically stimulated skeletal muscle supplement the heart in performing blood circulation. This assistance may take two basic forms. The first of these directly assist the natural heart by increasing aortic pressure at the same time as the heart. This may be implemented by wrapping the skeletal muscle about the heart. The second form increases circulatory system pressure during relaxation of the heart. The resulting increase in coronary perfusion provides the desired assistance to the heart by increasing myocardial oxygen supply.
With either form of cardiac assist, the heart is electrically sensed to ensure that the skeletal muscle is stimulated in the proper timing relationship to heart contractions.
FIG. 1 shows a typical cardiac assist system 5 used to provide indirect assistance to the cardiac function. Specifically this particular mode performs counter pulsation for enhanced perfusion. As discussed above, enhanced perfusion increased myocardial oxygen supply. It should be understood that this particular mode of cardiac assist is shown for the purpose of illustration only and not by way of limiting the scope of the present invention. Other modes of cardiac assist may be found in U.S. Pat. No. 4,813,952.
The human heart 10 is assisted by counterpulse contraction of skeletal muscle 22 and this results in the enhanced perfusion of cardiac tissue. Pulse generator 36 senses contractions of human heart 10 by lead 34. After a delay, pulse generator 36 sends stimulating pulses to skeletal muscle 22 via lead 100, thereby inducing contraction. As skeletal muscle 22 contracts, it reduces the diameter of chamber 20 which is coupled to aorta 12 via stub 16. This contraction increases aortic pressure, thereby improving perfusion through the coronary vascular system.
Skeletal muscle 22 must be conditioned to respond in the desired manner without or at least with minimal fatigue. U.S. Pat. No. 4,411,268 issued to James Cox, incorporated herein by reference, teaches such a method of conditioning.
FIG. 2 is a plan view of a chronically implantable lead 100 according to the present invention for stimulation of skeletal muscle 22 which powers cardiac assist system 5 of FIG. 1. Proximal end of lead 34 contains a connector 102 which couples to pulse generator 36 (not shown in FIG. 2.) A connector 102 has sealing rings 104 which provide a fluid tight connection with pulse generator 36. A terminal pin 106 electrically couples lead 100 to pulse generator 36.
An insulating sheath 101 electrically insulates lead 100, and specifically coiled conductor 108. Coiled conductor 108 is coupled at one end to connector 102 and runs to its distal end 107. An electrode 114 is fashioned from an uninsulated portion of coiled conductor 108. Electrode 114, therefor, may be electrically connected to pulse generator 36.
A strand 120 of suture material of polypropylene or other polymer is attached to distal end 107 of coiled conductor 108. A curved surgical needle 118 is mechanically attached to distal end of strand 120 of suture material.
A drug (such as a steroid or antibiotic) may be releasably imbedded within the polymer of strand 120. During the life of lead 100, this drug elutes out into the surrounding tissue at a predetermined rate. Preformed helix 122 is deformably molded into strand 120. Further description of imbedding a drug within strand 120 may be found in U.S. Pat. No. 5,086,787 to Grandjean et al., incorporated herein by reference. A detailed explanation of preformed helix 122 is found in U.S. Pat. No. 4,341,226 issued to Peters, incorporated herein by reference.
FIG. 3 is an enlarged partial view of coiled conductor-suture interface 109 of a stimulation lead 34 according to the prior art. As seen coiled conductor 108 was attached to strand 120 through a crimp core 111. As seen crimp core 111 presents a relatively bulky dimension, and specifically wider diameter, as compared to coiled conductor 108 and strand 120.
FIG. 4 is an enlarged partial view of coiled conductor-suture interface 109 of a stimulation lead 34 according to the present invention. As seen coiled conductor 108 is attached to strand 120 through use of a taper 113. Specifically coiled conductor 108 is tapered to a dimension so that it firmly is attached to strand 120. Taper 113 may be accomplished in any known manner including swaging. Although not specifically depicted the region of strand 120 engaged by taper 113 may be roughened so as to decrease its smoothness and enhance the grip of taper 113 thereto. Any suitable techniques may be used to provide such a rough surface including knurling strand 120. In addition an adhesive may also be applied to strand 120 in the vicinity of taper 113 to enhance the grip of taper 113 thereto. Finally to enhance the grip of taper 113 to strand 120 the coils of taper 113 may also be spot welded to one another once the strand and coiled are joined.
FIG. 5 is a schematic view of lead 34 according to the present invention positioned in a skeletal muscle. As seen needle 118 enters skeletal muscle 22 at puncture 128. It proceeds along path 132 and exits skeletal muscle 22 at exit point 130. As needle 118 proceeds through muscle 22 it pulls strand 120 and coiled conductor 108 therewith. Because taper 113 is dimensioned as less than the widest dimension of coiled conductor 108 lead 34 may be inserted relatively easier than the lead featuring interface 109 shown in FIG. 3. Preformed helix 122 sustains electrode 114 in contact with skeletal muscle 22 at puncture point 128. If glucocorticosteroid is used, it elutes out from strand 120 all along path 132 including puncture 128 and exit point 130 to minimize acute and chronic inflammation.
FIG. 6 is an enlarged partial view of coiled conductor-suture interface 109 of an alternate embodiment for a chronically implantable stimulation lead according to the present invention. This embodiment is the same as that previously described with the exception of a retaining collar 115 positioned on taper 113. Collar 115 is stressed to provide additional clamping to strand 120 from coiled conductor 108. As seen collar 115 presents dimension no larger than coiled conductor 108.
While the embodiment of the present invention has been described in particular application to cardiac assist technology, it will be understood the invention may be practiced in other electrode technologies where the aforementioned characteristics are desirable, including neurological and muscle stimulation applications.
Furthermore, although the invention has been described in detail with particular reference to a preferred embodiment, it will be understood variations and modifications can be effected within the scope of the following claims. Such modifications may include substituting elements or components which perform substantially the same function in substantially the same way to achieve substantially the same result for those described herein. | An intramuscular lead for the electrical stimulation of muscle tissue. The improved lead has a needle connected to a strand of suture, a coiled conductor coupled to the strand by a tapered section of the coiled conductor, an insulative cover covers part of the coiled conductor, and a terminal connector coupled to the coiled conductor provides a connection to a pulse generator. Through such a construction the lead may be more readily introduced through muscle tissue. | 0 |
BACKGROUND OF THE INVENTION
The present inventon is directed to a device for pressing a pile of sheets in a feeding unit or station such as the feeding station of a folder-gluer.
In folder-gluers known so far, the sheets are transferred from a feeding station to another station of the machine by conveyor means having a plurality of endless lower belts which are arranged underneath a pile of sheets which are to be introduced into the machine. These lower belts are operated with means for preventing passage of more than one sheet from the bottom of the stack which means include one or several frontal stops called gauges or gates each having a lower edge. The gauges are positioned so that the lower edge is spaced above the surface of the belt a distance equal to slightly more than the thickness of one sheet.
During processing of sheets of corrugated cardboard, it is often difficult to draw only the lowermost sheet from the bottom of the pile. This difficulty is due to the fact that it is hard to vertically adjust the lower edge of the gauge with regard to the thickness of the cardboard. This adjustment is quite easy when processing solid pasteboard or cardboard sheets. However, if the machine is processing corrugated cardboard, the operation becomes more difficult because while the thickness of the sheet may be constant, the sheets tend to curve and thus it does not lie in a single plane. As is obvious, the excessive bending of a corrugated cardboard sheet will cause difficulty with passage of the sheet below the gauges due to the effective thickness of the sheet being different at different locations. Thus, corrugated cardboard sheets cause problems at the feeding station.
Simple solutions have already been suggested to compensate for these inconveniences created by the corrugated cardboard sheets. One of the solutions recommends the use of a presser mounted on top of the pile of sheets to be introduced into the machine. This device acts along a plane which is defined by the gauges and presses the pile to thus flatten the sheets in the pile. Consequently, all the sheets in the pile will have the same thickness at the location of the gauge.
The device mentioned hereinabove is made of one or several counterweights mounted on guiding rails. These counterweights are freely movable along the guiding rails and shift downward toward the lower endless belts of the feeder when the sheets are introduced into the machine. When the feeder is to be resupplied with a new pile or batch of sheets, these counterweights have to be lifted manually and kept in their elevated position during the loading of a new pile into the feeding apparatus. This device is quite economical as it does not require expensive equipment to built the counterweight system. However, the loading of a new pile of large sheets into the feeder can be difficult. The operator has to use both hands to load the large sheets into the feeder since the pile is heavy and not easy to handle. Consequently, he cannot lift and hold the counterweights which act on the pile and simultaneously load the new batch of sheets into the feeder. This requires the operator to either request help from another person or to use several steps to load the sheets into the feeder. Because of these problems with loading new sheets into the pile, the production of the folded and glued boxes by the folder-gluer is disturbed or even slowed down.
SUMMARY OF THE INVENTION
The present invention is directed to eliminating the above mentioned drawbacks of the pressing device by offering the operator of a folder-gluer a pile pressing device which leaves his hands free for the loading operation of a new batch of sheets.
To accomplish these aims, the present invention is directed to a device for pressing a pile of sheets in a feeding station unit, said feeding unit having a conveyor means with continuous belts for transporting a bottom sheet in a pile of sheets and means for preventing passage of more than one sheet at a time from the bottom of the pile, said means including a gauge with a lower edge, support means including a support member for mounting the gauge in the feeding unit with the lower edge spaced above the belt of the conveyor means by the desired distance. The device comprises a pressing carriage; a vertical path defined by at least one vertically extending rail mounted on the support member and a vertically extending slot on a surface of the gauge, said carrier having slide elements engaging the groove and each rail to guide the carriage along the vertical path, a pressing device mounted on the carriage including an infeed guide with an aperture; sensor means for determining contact with a batch of sheets being loaded into the feeding station including a switch mounted in said aperture of the infeed guide, a sensor plate and means mounting the sensor plate on the infeed guide for pivotal movement into and out of contact with the switch; and drive means for moving the carriage along the vertical path including a pneumatic piston mounted on a support having a piston rod attached to the infeed guide, setting means for adjusting the pressure of the piston holding the guide in contact with a pile, a drive means for commanding the vertical shifting and control means for checking the elevating and lowering speed so that the drive means continuously moves the pressing carrier and infeed guide downwardly to maintain the desired contact on the pile and when the sensing means detects the insertion of a new batch of sheets which trip the switch, the drive means reverses the movement to elevate the carriage to supply room for the added batch of sheets.
Preferably, the support means for each of the gauges includes an adjustable mount which allows lateral adjustment of the position of the gauge and the device for pressing in the feeding unit., Preferably, the drive circuit enables coupling additional pressing devices so that a single source of pneumatic fluid or compressed air can be utilized. In addition, the sensor blade preferably includes lateral flanges which have adjustable stops to enable controlling the amount of pivotal movement thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective schematic view of a feeding station being provided with the device in accordance with the present invention;
FIG. 2 is a longitudinal cross-sectional view of the device of FIG. 1 in a feeding station with portions in elevation and with portions broken away for purposes of illustration;
FIG. 3 is a plan view with portions broken away and removed for purposes of illustration of the device of FIG. 2; and
FIG. 4 is a schematic view of the pneumatic drive of the device in accordance with the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The principles of the present invention are particularly useful for a device for pressing a pile of sheets in a feeding unit or station which is generally indicated at 1 in FIG. 1. The feeding unit or station 1 has two lateral frames 2 and 3 which are held together in parallel arrangement by a crosspiece 4. The unit or station 1 has a conveyor means 6 (FIG. 2) which has a plurality of endless belts 5 which are spaced between the two lateral frames 2 and 3 (FIG. 1). The cross-piece 4 has rails 7 which are secured to it by fastening means such as screws (not shown). These rails are arranged so that their profile creates grooves 8 and 10 which are best illustrated in FIG. 2. A U-shaped base plate or stirrup 11 is adjustably mounted on the upper surface of the cross-piece 4 by a "T" nut 12 which is engaged with a tightening screw 13 that passes through a plate 14. As illustrated, an arm 15 is positioned between the plate 14 and the base plate 11. The arm 15 is made of two lateral plates 16 and 17 which (best illustrated in FIG. 1) are spaced apart by braces 18 and 19.
A support member 20, which is composed of parallel extending plates, is attached to the arm 15 and provides a mounting for a guage or gate 21. The gauge 21 is vertically adjusted by means of a setting screw 22 (FIG. 2). Each wall of the plates forming the support member 20 is provided with vertically extending slide elements or rails 23 (FIGS. 1 and 2) on which a pressing carriage 24 is engaged. The carrier 24 is guided on the rails 23 with the help of slides 27 (FIG. 3). The pressing carriage 24 is also guided with the help of a guiding slide 25 which is received in a groove 26 which is provided on a front surface of the gauge 21. A support 28, which has an L-shaped configuration as illustrated in FIG. 2, is mounted on the upper end of each of the two rails 23. The support 28 holds a pneumatic piston 29 which raises and lowers a pressing device 30 which is secured onto the pressing carriage 24. The unit 1 can be adjustably positioned along the transverse directions of the rails 7 by means of the adjustable mounts of the stirrup 11.
The pressing device 30 includes an infeed guide 31 which is secured on a front part of the pressing carriage 24 by means of screws 32. A supporting blade 33 is secured by screws 34 onto a lower part of the guide 31. The supporting blade 33, which is equipped with the guide slides 25, presses the leading edge of a pile 58 by engaging the top sheet therof. The guide 31 has a plate portion 60 equipped with bearings 35 and 36 (FIG. 3) which receive axles 37 and 38 supporting a sensor plate 39 which has two flanges 40 and 41. Two shiftable stops 42 and 43 are mounted on these flanges and can be adjusted to engage an upper surface of the plate 60 to limit the pivoting of the plate 39 in a counterclockwise direction. As best illustrated in FIG. 3, the infeed guide 31 has an aperture 44 and a switch 45, which is mounted on a block 46, is mounted with its roller contact 47 (FIG. 2) extending in and partially through the aperture 44. Thus, the roller 47 of the switch 45 will be engaged by the sensor plate 39 as it pivots in a clockwise direction against the plate portion 60 of the guide 31.
An upper portion of the infeed guide 31 is provided with a lug 48 which receives a fork 49 that is secured on the end of a piston rod of the pneumatic piston 29. The pneumatic piston 29 will be driven by a pneumatic circuit which includes the switch 45. The circuit also includes a setting means or element 51 which adjusts the pressing force, drive means or element 52 which commands the vertical shifting of the pressing device 30 and a controlling element or means 53 for checking the elevation and lowering speed of the pressing device 30.
If the sheets of the pile are made in the transverse direction, the arrangement of several pile-pressing devices along the transverse width of the feeding station 1 is desirable. Thus, the control includes two couplings 54 and 55, which are mounted on an upper part of the device and are used for coupling the control circuit of one pressing unit with another so that a single source of compressed air can be utilized to operate all the units.
As best illustrated in FIG. 4, the pneumatic circuit includes a compressed air supplied from a source 56 which is blasted through a check valve to a distributor 57 as well as to a drive means or temporisator element 52 and the switch 45. The compressed air is then distributed from the distributor 57 to various elements 51, 52 and 53 to control the motion of the pneumatic piston 29.
The distributor 57 is pneumatically driven either by compressed air comming from the switch 45 or by air comming from the temporisator element 52. the distributor 57 dispatches air to the piston 29 in order to command the up and down motion of the piston 29. The setting means 51 allows to optimize the force applied on to the pile 58 and the controlling means 53 which is a flow regulator controlling the speed of the up and down motion of the piston 29. The drive means 52, which is a time delayer, is destined to delay the moment of the reverse motion of the piston 29.
The pressing device operates in the following. When a batch of sheets is being loaded on the endless belts 5 of the conveyor means 6, the sensor plate 39 of the pressing device 30 will be pushed and cause the roller or follower 47 of the switch 45 to activate the switch. The activation of the switch 45 lifts the pneumatic piston 29. But the switch 45 is connected with the drive element 52 which, if properly adjusted, is going to progressively restore the air pressure in the pneumatic piston 29 causing it to move down again. The air pressure delivered to the pneumatic piston 29 can be adjusted by means of the setting element 51 which allows a modification of the pressing force of the pressing device 30 on an upper face of the pile 58 of sheets. It should be noted that the pressing device engages the upper sheet with the supporting blade 33 and that in a normal operation, the sensing plate 39 of the sensing means does not engage the upper surface but is pivoted to a position out of contact with the switch 45 which is deactivated. Thus, in this position, which is shown in bold lines in FIG. 2, air is delivered through the setting means 51 to move the piston in a downward direction.
Each time the sensor plate 39 is contacted by the front part of a new batch of sheets being introduced to the pile 58, the pressing device 30 is lifted and momentarily liberates the front part of the pile 58 from any pressure as the batch is being introduced into the feeding station 1. It thus allows the loading of a new batch on top of a previous batch without any manual removal of the pressing device 30 from its operating location. As soon as the new batch is properly loaded, the pressing device will again engage the top sheet of the newly constituted pile. Of course, an adequate setting lifts the pressing device 30 just enough to allow the loading of the new batch. Thus, the time, while the batch is to be introduced into the feeding station of the folder-gluer and while the pile in the folder-gluer is not under pressure, remains as short as possible. Thus, with the pile-pressing device removed temporarily, the operator has a simplified and rapid loading of the feeding station 1 without requiring the help of another operator even when loading or processing large sheets.
Although various minor modifications may be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent granted hereon, all such modifications as reasonably and properly come within the scope of my contribution to the art. | A device for pressing a pile of sheets in a feeding unit or station including a vertically movable pressing carriage with a pressing device being guided in a vertical path formed by rails and a groove provided in a front surface of a gauge of the feeding unit. The pressing device includes a sensing arrangement acting on a switch connected in a control circuit for a pneumatic drive so that when introducing an additional batch of sheets into the feeding station the sensing device actuates the pneumatic piston to retract the pressing device to provide clearance for the additional batch. | 8 |
FIELD OF THE INVENTION
This invention relates generally to a deflection-controllable roll for a calender or similar device, and more particularly to a roll, in which, with the aid of hydrostatic support elements, a roll sleeve is supported on a fixed carrier that penetrates the roll sleeve. The support elements have a pressure portion which bears against the roll sleeve, forming a support area facing the inside surface of the roll sleeve. The pressure portions have at least one pocket, fully encircled by an edge, and a piston which delimits, by means of a pressure area facing the carrier, a pressure chamber which is connected on the one side with a feed line in the carrier, and on the other, with the pocket by means of a throttle.
BACKGROUND OF THE INVENTION
A deflection controllable roll of this type is known, for example, from U.S. Pat. No. 3,802,044, which discloses a roll suitable not only for calenders, but also for glazing rollers; presses; batches of paper, cellulose and printing presses; or rolling mills for steel, plastic and the like.
In conventional rolls, the piston of the support dement engages a radial bore in the carrier which produces a circular support area. The range of force that can be applied in this way is limited by the available hydraulic pressures. The hydraulic pressures are limited in the downward direction by the pressure control valves and in the upward direction by the materials that are used. As a result, it is not possible to selectively operate the same deflection-controllable roll with a wide range of line loads in the roll gap.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved deflection-controllable roll.
It is a further object of the present invention to provide a deflection-controllable roll capable of operating in a wide range of adjustable line loads.
According to the invention, at least one of the support elements is enclosed as an inner support element by a ring-shaped outer support element, and the outer support element has an outer pressure portion which bears against the roll sleeve, forming a support area facing the inside surface of the sleeve. The outer support element also has an additional ring-shaped outer pocket that is fully edged, and an outer piston which delimits, by means of a ring-shaped outer pressure area facing the carrier, an outer pressure chamber, which is connected on one side with a second line in the carrier, and on the other, with the outer pocket by means of a second throttle.
An inner and an outer support element are allocated to a support region, without a significant increase in the space requirement. These support elements can be actuated either individually or in common. As a result, it is possible to apply varying forces so that a greater range of adjustable line loads is provided.
The inner and outer pistons are positioned adjacent to each other along a single cylindrical area. Since the pistons are positioned adjacent to each other, the size of the support elements can be reduced, resulting in a significant space savings.
The inner piston is cylindrical, engages with a cylindrical bore and forms with the bore, the inner pressure area. It is also preferable that the outer piston is formed as a hollow cylinder, engages with an extension of the cylindrical bore having a larger diameter than the main portion of the cylindrical bore, and forms with the cylindrical bore, as well as with the inner piston, the outer pressure chamber. This results in a simplified design with parts that can be manufactured easily.
It is also advantageous to fasten a driver to the inner piston that engages under the outer piston and is capable of actuating the outer support element in the direction of the piston's stroke. The driver also prevents unwanted displacement of the outer support element in the event of actuation of the inner support element only.
In a preferred embodiment, the inner pressure portion has a larger outside diameter than the inner piston, and the outer pressure portion has a larger outside diameter than the outer piston. The outer pressure portion has a step-like recess, the outer diameter of which corresponds to that of the inner pressure portion, for receiving the inner pressure portion. The increased size of the pressure portions makes it possible to provide larger pocket areas, which provides larger support areas.
The cylindrical gap between the inner and the outer piston, as well as between the inner and the outer pressure portions, are each sealed by means of a ring seal and are connected with an intermediate chamber, between the roll sleeve and the carrier, by means of a channel provided between the ring seals. As a result of this connecting channel, the stepped area of the recess is under a neutral ambient pressure. It is preferable that the height of the inner pressure portion, between its underside and the outer area of the edge of the inner pocket, is smaller than the height of the recess, between its base and the outer area of the edge of the outer pocket. In this way, a gap is provided at the step of the recess which allows a radial inward movement of the inner support element, so that upon actuation of only the outer support element, frictional losses can occur solely in the region of the outer pocket's edge.
The inner support element and the outer support element are held in a pendulum-like manner with respect to the carrier. This allows a matching of the support areas to the inside surface of the sleeve, even if the carrier and/or sleeve deform.
The inner piston and the outer piston are guided in a bearing element which has a spherical surface and which is supported in a spherical mounting of the carrier.
A central groove is provided between the bearing element and mounting, along with a ring groove that surrounds the central groove in a concentric manner, by means of which the pressure medium is directed to the inner and outer pressure chambers. The grooves allow the pressure medium to be supplied even during the pendulum motion. In addition, when the grooves are appropriately dimensioned in comparison with the pressure areas, they hydraulically relieve the bearing element.
Furthermore, the inner pocket and/or outer pocket are sub-divided, by means of separating webs, into a number of partial pockets which are offset in the radial direction. Each of the partial pockets is connected with the inner and outer pressure chambers by a throttle. As a result, the stabilization of the support elements is increased by means of the partial pockets being individually supplied with pressure medium.
Preferably, at least the inner piston's throttle is bridged by a check valve that opens towards the pressure chamber. In this way, if only the outer pocket is supplied with the pressure medium, the check valve ensures that there is no buildup of pressure in the inner pocket.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross-section through a region of support of the preferred support element combination according to the present invention.
FIG. 2 is a top view of the inner and the outer support elements of FIG. 1.
FIG. 3 is a longitudinal cross-section through a region of support of an alternate support element combination according to the present invention.
FIG. 4 is a top view of the inner and the outer support elements of FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2, a roll sleeve 1 is penetrated by a fixed carrier 2, which supports the roll sleeve 1 by means of a support element combination 3. As disclosed in U.S. Pat. No. 3,802,044, several regions of support can be placed adjacent to each other, axially. Therefore, since a series of the support element combinations 3 can be configured in the same manner as shown in FIG. 1, only a limited region of support is shown. In particular, the roll sleeve 1 can work together with a second roll to create a roll gap in which paper or other material can be processed by means of compression forces.
The support element combination 3 includes an inner support element 4, which has a pressure portion 5 and a portion which is a cylindrical piston 6. The pressure portion 5 bears against the roll sleeve 1, forming a support area 7, in which there is located a pocket 8 that is fully encircled by an edge 9. The piston 6 engages a cylindrical bore 10, and has a pressure area 11 which, along with the bore 10, delimits a pressure chamber 12. The pressure chamber 12 is connected on the one side with the pocket 8, by means of a feed line 14 which is equipped with a throttle 13, and on the other side, in the carrier 2 by means of a feed line 15 to a pressurized oil supply.
An outer support element 16 has a pressure potion 17 and a portion which is a hollow cylindrical piston 18. The pressure portion 17 bears against the roll sleeve 1, forming a ring-shaped support area 19 with a ring-shaped pocket 20, which is fully encircled by an edge 21. The piston 18 engages an enlarged cylindrical bore extension 22 which is formed within the bore 10, and is guided on the inside, along the piston 6. The piston 18 has a ring-shaped pressure area 23 which, along with the bore extension 22 and the piston 6, forms a ring-shaped pressure chamber 24. The pressure chamber 24 is connected on the one side with the pocket 20 by means of a feed line 26 which is equipped with a throttle 25, and on the other side, in the carrier 2 by means of a feed line 27 to a pressurized oil supply.
The inner pressure portion 5 has a larger outside diameter than the associated piston 6. The outer pressure portion 17 has a larger outside diameter than the associated piston 18. In this way, the pressure-active support areas 7 and 19 can be larger than the associated pressure areas 11 and 23, which provides a larger support area on the roll sleeve 1. Furthermore, a recess 28 with a step 29 is provided in the outer pressure portion 17, which serves to accept the inner pressure portion 5. By means of ring seals 30 and 31 between the peripheral area of the inner pressure portion 5 and the inner area of the recess 28 and the peripheral area of the inner pressure portion 5 and the inner area of the pressure portion 17, the pressure that results in the pocket 20 is prevented from acting upon the underside of the pressure portion 5. In this regard, it is advantageous to provide a channel 32 between the ring seal 30 and the ring seal 31 and between the two pistons 6 and 18, which leads to an intermediate chamber 33 between the roll sleeve 1 and the carrier 2. The pressure that results then also acts upon the lower ring area of the pressure portion 5.
The height of the inner pressure portion 5 between its underside and the outer area of the edge 9 is shown by a 1 . The height of the recess 28 between the base of the step 29 and the outer area of the edge 21 of the outer pocket 20 is shown by a 2 . When there is actuation of the outer support element 16, the inner support element 4 is actuated as a result. In addition, an annular spring 34 is provided on the piston 6 as a driver, and engages under the piston 18 and as a result, actuates the outer support element 16 when the inner support element 4 is actuated. As a rule, the heights a 1 and a 2 are of equal size. In some cases, however, it is advantageous for a 1 to be somewhat smaller than a 2 , which will be explained further.
A pressurized oil supply is represented schematically in FIG. 1. A pressure source 35, preferably in the form of a pump, operates three closable pressure regulators 36, 37 and 38.
If the pressure regulator 36 is activated, pressurized fluid, such as oil, will enter into the pressure chamber 12 though the feed line 15, thereby actuating the inner support element 4. The oil then flows through the feed line 14 and the throttle 13, into the pocket 8, and possibly through the edges 9 and 21 into the intermediate chamber 33.
If the pressure regulator 37 is activated, pressurized fluid will enter into the pressure chamber 24 through the feed line 27, thereby actuating the outer support element 16. The fluid then flows through the feed line 26 and the throttle 25, into the outer pocket 20, from which the fluid can flow through the edge 21 into the intermediate chamber 33, and possibly through the edge 9 into the pocket 8.
The pressure regulator 38 is used to keep the pressure in the intermediate chamber 33 at a selected value.
Finally, the feed line 15 may be connected with a discharge line with the aid of a simple check valve 39, so that the inner support element 4 acts as a pressure sink. For this purpose, the throttle 13 should be bridged by a check valve.
To operate the inner support element 4 only, the feed line 27 is closed off by the pressure regulator 37 and only the pressure chamber 12 is supplied with pressure medium through the feed line 15. The inner support element 4 then acts as a conventional support element with a force which is determined by the pressure in the pocket 8 and the effective support area 7 of the inner support element 4. As this occurs, the outer support element 16 can be lifted by means of the driver 34. In this way, a low line load level can be achieved with the desired pressure-force ratio.
To operate the outer support element 16 only, the feed line 15 is closed off by the pressure regulator 36 and only the pressure chamber 24 is supplied with pressure medium. The pressure that results in the associated pocket 20 also acts in the pocket 8 of the inner support element 4. Since both of the support areas 7 and 19 are activated, the roll sleeve 1 can process a high line load, even though only moderate pressures are being used. If the height a 1 is smaller than the height a 2 , frictional losses occur only at the gap between the outer edge 21 and the roll sleeve 1.
To operate both support elements 4 and 16, different pressures are fed to the pressure chambers 12 and 24. For example, the pressure in the intermediate chamber 33 is set to a value greater than zero. In the outer pocket 20, a pressure is set that is greater than the pressure in the intermediate chamber 33. In the inner pocket 8, a pressure is set that is greater or less than the pressure in the intermediate chamber 33. In this way, the level for the line load is maintained with the outer support element 16, while variations in load can be fine-tuned with the inner support element 4. If the height a 1 is equal to the height a 2 , the outer support element 16 ensures that the correct gap between the edge 9 and the roll sleeve 1 is maintained at the inner support element 4.
Referring to FIGS. 3 and 4, reference numbers for corresponding parts are used that have been increased by 100 from those used in FIGS. 1 and 2.
Preferably, the inner support element 104 and the outer support element 116 are guided inside a bearing element 140, having a spherical surface 141 and supported in a two-part spherical mount 142 of the carrier 102. As a result, the support elements 104 and 116 can move in a pendulum-like manner relative to the carrier 102, due to the action of the bearing element, so that the feeding of the pressurized medium is maintained, thus providing a constant support pressure. However, matching connecting grooves, namely a central groove 143 and a ring groove 143a that surrounds the central groove 143 concentrically, are provided, each of which is surrounded by a seal 144. The connecting grooves 143 and 143a can be provided in the bearing element 140 instead of in the carrier 102. By means of appropriately dimensioned connecting grooves 143 and 143a, the bearing element 140 is hydraulically relieved with respect to the carrier 102, which eases the pendulum-like motion of the entire support arrangement.
At the inner support element 104, the inner pocket 108 is divided by means of separating webs 145 into four partial pockets b, e, d, and e, which are offset in the radial direction, each of which is connected to the inner pressure chamber 112 by means of a feed line 114 and associated throttle 113. Similarly, the ring-shaped pocket 120 is divided by means of separating webs 146 into partial pockets f, g, h, and i, which are offset in the radial direction, each of which is connected to the ring-shaped pressure chamber 124 by means of a feed line 126 and associated throttle 125. In this case, the ring-shaped pocket 120 is delimited on the inside by the circumferential wall of the pressure portion 105.
The pendulum-like support of the support elements 104 and 116 allows a matching of the support area to the inside of the sleeve 101, as a result of which a uniform lubrication gap is provided over the entire support area. Through the use of the partial pockets b through i, this matching occurs automatically, which results in an increased stability of the bearing element 140.
The throttle 113 in the feed line 114 is bridged by a check valve 147 that opens to the inner pressure chamber 112. As a result, pressure cannot build up in the pocket 108 of the inner support element 104 if the pressure medium is fed only to the ring-shaped pocket 120.
While the embodiments of the invention shown and described are fully capable of achieving the results desired, it is to be understood that this embodiment has been shown and described for purposes of illustration only and not for purposes of limitation. Other variations in the form and details that occur to those skilled in the art and which are within the spirit and scope of the invention are not specifically addressed.
For example, any number of partial pockets can be provided. Also, the piston 6 of the inner support element 4 can be shortened and the inner support element 4 guided entirely inside the outer support element 16, in conjunction with which the ring-shaped piston 18 of the outer support element 16 is guided within a corresponding ring-shaped groove in the carrier 2 or in the bearing element 140. Therefor, the invention is limited only by the appended claims. | A deflection-controllable roll for a calender has an inner support element and an outer support element. Each of the two support elements has a pressure portion and a piston. The pressure portions have support areas with inner and outer pockets. The pistons have pressure areas which delimit an inner pressure chamber and an outer pressure chamber, both of which are connected on one side with the associated pocket by a feed line equipped with a throttle, and on the other side, by a feed line in the carrier. In this way, the deflection-controllable roll is capable of operating in a wide range of line loads, using the available pressures. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a circular knitting machine particularly suited for the production of cut pile.
2. Description of the Prior Art
The integrated cutting of pile loops in the knitting machine is of particular commercial importance, as a subsequent cutting by a shearing process during finishing results in a high waste of pile material and requires additional finishing steps.
Known methods to solve this problem by severing pile loops in the knitting machine have fallen into four groups.
In the first group the pile loops are severed by being drawn over a sharp knife-like cutting edge which penetrates as a result of its extension into the pile loop and thus severs it. As for example is already known from U.S. Pat. No. 1,546,790, the cutting edge can be a an extension of the pile forming edge on a sinker which is positioned in a sinker ring. Similarly, the cutting edge can be provided at a pile element arranged in the cylinder in the manner described in West German Specification No. 2,917,378 or last German counterpart 138,227. The cutting edge is there inclined with respect to the direction in which the pile elements retract and is positioned so that the pile loop is drawn during the retraction of the pile element until it is severed on the cutting edge. Furthermore, such a cutting edge can be arranged on the shank of a hooked pile element underneath the hook, as is shown for example in West German Specification No. 2,704,295. The pile loop formed by the hook is pressed down by a holding down wheel while the pile element is raised to such an extent in which the cutting edge will tear the drawn loop while the needles remain in miss position. It is obvious that extending or stretching the pile loop to sever it raises to problems in a number of respects and as a result is relatively unreliable. Reliable severing can only be assured over long periods if pile material is used as fine as possible and having a low twist with a low tenacity and and also having a very limited elasticity, so that the pile loop is actually severed simply by drawing if over a cutting edge. Since the stretched pile loop slides over the cutting edge, the cutting edge is quickly worn, which results in broken pile elements and thus fabric faults, machine stoppage and high replacement costs for pile and/or cutting elements. These disadvantages can be avoided to a certain extent if an independently movable knife-like cutting member is arranged between adjacent pile elements or lamellae as taught in U.S. Pat. No. 4,026,126, which hold the pile thread extended for cutting by the moving cutting element. The movable cutting element is provided with an upper sloping cutting edge and is moved upwards between the pile elements (located in the cylinder) and between their hooks, in order to sever the pile loop increasing their extent. Although substantial wear might be expected, the above-mentioned disadvantages are substantially reduced in such a circular knitting machine, but other disadvantages result which will be further explained below.
In the second group of methods the pile loops are severed by being crushed by a crushing wheel. For example according to the teaching of U.S. Pat. No. 1,596,527, the pile loop is formed over a pile element located in the dial, the pile element is then supported from beneath and a crushing wheel is pressed on it from above, in order to crush the pile loop. In the example of U.S. Pat. No. 3,933,907 hooked pile elements located in the dial form the pile loop which is subsequently abraded by a crushing wheel. In British Pat. No. 891,937 the pile loop is formed over an arcuate sinker neb and slides rearwardly thereon by subsequent knitting operations, where it is engaged by a crushing wheel and abraded. Such crushing or abrading of pile loops can however only be satisfactorily accomplished if sufficient time is allowed for it. This is only possible with low speed machines. Special problems result when using high tenacity yarns.
In the third group of methods the pile loops are transferred to a separate cutting element where they are cut. One of the two portions of the pile loop is so offset with regard to the other--by a correspondingly formed dial according to British Pat. No. 813,357 or by a displacement wheel according to British Pat. No. 849,710--that a transfer element can be introduced into the pile loop, which serves as support during cutting. Such an insertion of cutting elements and supports into the pile loop is, however, only possible in coarse cut machines, as with finer cuts the two portions of the pile loop are too close to each other and cannot with the necessary degree of certainty be brought into such offset or staggered relationship.
In the fourth group of methods to sever pile loops, the severing is effected by two cutting edges movable relative to each other. In German Pat. No. 1,153,482, movable pile elements are arranged in the dial having upright projections on their outer ends with cutting edges on the dial side of the projections. In the same slots of the dial, side by side to the pile elements, fixed cutting elements are dispersed, projecting with their cutting edges on the outer ends of the dial. Pile loops are formed on the shanks of the pile elements adjacent the cutting edges and by retracting the pile elements and the loops, their cutting edge will contact the cutting edge of the cutting element and in cooperation they will cut the pile loops. In an improvement, known from West German Pat. No. 1,585,051, the cutting elements are slightly pre-bent, so that the cutting edges of the cutting elements are resiliently pressed against the cutting edges of the pile elements to avoid a deflection from the cooperating cutting edges under cutting conditions. It is also known from German Patent specification No. 2,423,700 to arrange a movable hooked pile element tightly in a U-shaped cutting element having cutting edges on both sides so as to cooperate with the cutting edge of the pile element which is a portion of the hook when the elements are moved relative each to each other subsequent to the knitting process.
As a result of the cooperation of two cutting edges when moving at least the pile elements unlike in the first group of methods with only one cutting edge, the serving is not realized by an increased extent of the pile loop, but rather by relative movement of the cutting edges without any substantial additional extending of the pile loop. Furthermore the pile loops do not need to run under tension over the cutting edges so that by virtue of a cutting concept with relatively movable cutting edges both the abrasion of the cutting edges by the rubbing effect of the pile loops is reduced and the abrading of the pile thread, completely or partly by drawing over the cutting edge is avoided when the pile loops are formed. However, one particular disadvantage of such an arrangement is that the pile elements and the cooperating cutting elements, which in the example of West German Patent specification No. 2,423,700 is moreover arranged on either side of the shank of the pile element, must be arranged in the same slot and be capable of relative movement therein. The relative movement of elements side by side presupposes that increased friction must not occur between the elements. The necessary tolerance for an easily relative movement is detrimental to the cutting process, since then the cutting edge and the cooperating cutting edge must either have a corresponding relative tolerance, as in the example of DE-OS No. 2,423,700, or they can be relatively easily flexed away from each other by the pile loop, as in the example of DE-PS No. 1,153,482. Even with elastic compression of the stationary cutting element towards the pile element as is provided in the example of DE-PS No. 1,585,051, such a gap cannot be avoided, as on account of the necessary relative movability only light elastic compression can be exerted, which then makes it possible to still deflect the cutting edge of the pile element from cooperating cutting edge. Thus as soon as the cutting edges exhibit first effects of wear and if additional interfering factors unavoidable in practice add their effects such as damage or even only contamination of the elements which are moved against one another such as by fibre dust or solidified lubricant, the pile loop is no longer cut, but merely jammed therebetween.
A still greater basic disadvantage of these methods of arranging at least two relatively movably side by side elements in the same slot that also is to be avoided in moving knife-like cutting element of U.S. Pat. No. 4,026,126 between adjacent pile elements lamellae directs in that it necessitates too coarse a cut of the machine. The overwelming majority of pile machines are built with 18 or 20 cut per inch (Imperial). Of the--at best--1.4 mm per needle available, 0.5 mm is already occupied by the cut itself. The pile elments must be extended between the needles, and an unavoidable predetermined space has to be left between the needles and the pile elements for looping the pile. On that account the pile element can only have a thickness of at most 0.5 mm. This results that in the examples of German Pat. Nos. 1,153,482 and 1,585,051 the pile elements and the cooperating cutting elements can only be at most about 0.25 mm thick. Because of this neither an adequate compression of the two cutting edges onto the other nor an adequate inflexibility of the cutting edges can be achieved, so that such small element thicknesses are not acceptable in practice. Thus a coarser cut of the knitting machine is required.
In all known possible methods of integrated severing of the pile loops into the knitting machine, there is the common problem produce a equal pile side and a uniform stitch structure, in which the base thread covers the pile thread on the stitch side by plating. When the needles are being extended, the stitches are enlarged by forcing the latch open and clearing the latch and also during retraction as the the needle hook is being pulled through. As the needle loops of the base fabric are connected wale-wise and course-wise, they afterwards re-assume their original form. If the pile loops, however, are severed subsequent to the knitting process, there is no longer any possibility of retraction of the enlarged stitch loops of the pile thread until a subsequent course is knit. When knitting, the pile threads into the needle stitches of the base fabric it is desired to produce a uniform pile and stitch structure which is effected when the pile loops are maintained at least partially until extended the stitches are cleared from the needles by the subsequent course, and therefor no further protruded needle loops of the pile-threads are avoided as a result of their frictional connection to the acting needles.
Several methods of preventing enlarged stitches are known. Some of them are disclosed in various embodiments of a known circular knitting machine according to West German Specification No. 2,918,203, in which the severing of the pile loops is also realized corresponding to the above-mentioned first group of known methods similar to the teachings of West German Specification No. 2,704,295, so the the pile elements, after clearing the stitches of the previously knitted course from the needles, the needles are moved and the pile loops are severed by a cutting edge disposed opposite the hook opening and cooperating with a blade, pressing the pile loops against the dial. The elements are therefore arranged in the dial. According to the embodiment of FIGS. 2 to 9 of West German Specification No. 2,918,908 and also according to the teaching of East German Specification No. 136,227 or U.S. Pat. No. 1,596,527, subsequent to each pile course, a single threaded course is knit to clear the pile threads from the needles. Because of this, the pile is naturally less dense while the number of pile loops projecting from the base fabric is halved. According to the embodiment of FIGS. 10 to 19 of West German Specification No. 2,918,903 two pile hooks are arranged in each slot of the dial which alternately form and sever the pile loops; this results as explained above in detail with a coarse cut of the machine according to the required measurement of the pile elements, and moreover mutual interference between the pile elements and jamming of the pile loops may occur instead of its being severed. According to the embodiment of FIGS. 20 to 25 of West German Specification No. 2,918,903 and to the teaching of West German Specification No. 1,153,482 each course is knit only have a portion of the needles and pile elements; because of this, however, only a portion of a course is knit which is completed by the subsequent feeder and the productivity of the knitting machine is halved.
A fundamentally different possibility for a reprotruding the stitches of the pile thread by extending the pile loops is known from British Pat. No. 891,973 which belongs to the above described second group of methods and in which the pile loops are formed over curved sinker nebs in the dial, but are not severed immediately after their formation. Rather the pile loops slide rearwardly on the curved sinker neb while subsequent pile loops are knitted. Each pile loop is severed by means of an abrading wheel when the subsequent stitch of the pile thread has been completely knocked over, so that the severed pile loop then clears the sinker neb and can be pulled off by the fabric take-down. The curvature of the sinker neb is chosen so that the take-down friction causes the knitted pile loops to slide into the area of the abrading wheel. This requires the actual pile forming edge of the curved sinker neb be substantially horizontal or only slightly inclined to prevent the pile loops from sliding away undefined when they are formed by the cylinder needles. At the same time, the fabric take-down friction, acting in the same direction, must also effect a sliding movement of the pile loops along the curved sinker neb, even through the take-down strength acts substantially normally to the pile forming edge where the pile loop is formed on the sinker neb. In this manner the pile loops on the sinker nebs substantially hinder take-down and require high take down strength without precluding disturbances if e.g., different yarns with different friction on the sinker nebs are to be used. The high strength acting on the sinker nebs, to which must yet be added the pressure of the crushing wheel, necessitated a rugged construction for the sinker nebs which again results in the need to have a correspondingly coarse cut of the machine.
Naturally, the knitting latch needles have no effect on the pile threads if these are knitted into the base fabric by tuck stitches, described in the example of U.S. Pat. No. 2,933,907, West German Specification No. 2,704,295, West German Specification No. 2,423,700 and U.S. Pat. No. 4,026,126. By virtue of substantially extending free cutting of the pile loops according to the present invention, protruding pile loops are prevented so the pile thread is knitted to tuck stitches.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improvement over circular knitting machines of the general type described in U.S. Pat. No. 4,026,126 in which latch needles are positioned in the dial and pile elements in the cylinder, and in which to each pile element--here comprising two parallel, closely spaced pile elements lamellae--is arranged a relatively movable cutting element for cutting the pile loop. For each bicomponent pile element, therefore, together with the movable cutting element, the slot in the cylinder requires a width corresponding to the thickness of the three parts, generating a correspondingly coarse cut for the cylinder and dial. This coarse cut cannot be made finer because of the necessary dimensions of the elements in the cylinder, which must extend between adjacent needles. The severing itself is realized immediately subsequent to knitting of the base fabric by the hooks of the bicomponent pile elements cooperating with the projecting cutting element, so that the above described problems of not maintaining an extended pile loop to effect a clean jersey side of the fabric for knitting in the pile thread into the needle stitch would be encountered. The special knitting structure of the pile threads into the base fabric by means of special needles as specifically taught in U.S. Pat. No. 4,026,126 reduces the protruding of pile stitches Knitting the pile threads into needle stitches according to the above described severing method to produce uniform and clean stiches would not be possible.
It is another object of the invention to construct circular knitting machines of this general type with which a cut pile can be produced in fine gauge if so required and with any desired stitch construction by knitting of the base and pile threads all this without influence to the knitting process by the severing process.
BRIEF DESCRIPTION OF THE INVENTION
In one aspect, the invention relates to a circular knitting machine for knitting a cut pile fabric, with a dial and a cylinder where movable latch needles are arranged in the dial and pile elements as positioned in the cylinder, said pile forming elements having a pile forming edge. Spaced thereform, a cutting edge on to which pile loops previously formed on the pile forming edge slides by knitting subsequent courses, and an associated cooperating cutting element with a cooperating cutting edge which is actuated to and fro rectangular the said cutting edge to sever the loops.
The cutting element may be pivotally supported on the pile forming element and preferably so that it is arranged radially outwardly thereof with respect to the axis of the cylinder.
Alternatively, the cutting elements can be positioned in slots of a dial ring located radially outwardly of the cylinder.
In any event, the cutting element can have a cutting edge whch can be skewed with respect to the cutting edge of the pile forming element to effect the severing scissor like.
While the forming pile elements are arranged spaced beneath the latch needles when they cooperate with the cutting edges of the cutting elements the severing of the pile loops is effected, delayed if desired with respect to the formation of the loop in correspondence with the chosen distance from the pile forming edge to the cutting edge, when at least one additional pile loop is knitted and will not be influenced by the cutting edges. This advantage corresponds in substance to the method described in British Pat. No. 891,973, i.e. avoiding an unsightly appearance of the jersey side by a subsequent severing of the pile loops by effecting the severing process independently from the knitting process so that the knitting process can no longer be affected. In contrast to the teaching i.e. British Pat. No. 891,973 however, this method is realized according to the invention with forming elements arranged in the cylinder, on which the pile loops can slide from the pile forming edge to the upper end of the cutting edge without hindering the fabric take down in the defined direction thereof. Therefore the knitted fabric is held on the upright pile forming elements until it is cleared by severing the pile loops. This has no disadvantageous effect to the take down mechanism nor to the knitting process, so that according to the invention the method of producing a regular fabric with a desired appearance, as is it is basically known from British Pat. No. 891,973, can be readily used, and is, in the invention, without any problem or difficulty by the simple measure of arranging the cutting elements below the latch needles cooperating in this level with the cutting edge of the pile elements.
The cutting edges of the pile elements are upright, thus substantially parallel to the axis of the cylinder, and cooperate with the cutting edge of the cutting element. In contrast to knitting machines according to U.S. Pat. No. 4,026,176 the pile elements do not simply extend or stretch the pile loops to allow tearing by a knife-like cutting element, but themselves have a cutting edge which cooperates with the cutting edge of the cutting element in a scissor-fashion. The cutting element is for this reason projected in a direction transverse to the cutting edge of the pile forming element, thus transverse to the cylinder axis and not parallel to it as in the case of U.S. Pat. No. 4,026,126. Therefore, it is possible to arrange the cutting element independently of the pile forming elements in a slot of a sinker ring and thus does not increase the width of the slots for the pile forming elements in the cylinder with a consequent coarseness of the cut. It is only necessary to effect relative movement between the pile forming element and the cutting element each to the other for the actual cut in the axial region of the cutting edge of the pile forming element which is arranged at this time below the level of the latch needles in the dial and above the slots of the cylinder. Even in fine cuts there is enough space for the cooperating cutting edges of the cutting elements to slide in contact beside the cooperating pile forming elements. This gives a highly stabilized arrangement of both cutting edges and in a preferred embodiment of the invention there is even a relative skewing of the cooperating cutting edges of the cutting element and the cutting edge of the pile element so as to produce a real scissor-like effect for realizing a clean and safe cut and an automatic sharpening of the cutting edges and cooperating cutting edges. It is of considerable importance, moreover, that all projections required for the severing can be actuated simultaneously and independently of the projection required for stitch and loop formation, and therefor without any decrease of productivity resulting from a separate severing action.
The distance from the pile forming edges to the cutting edges and also the length of the cutting edges of the pile element and the substantially corresponding length of the cooperating cutting edges of the cutting element can be made sufficient so that a plurality of as yet uncut pile loops can string on the pile forming element and then slide into the area of the cutting edges.
The distance from the upper end of the cutting edge and the pile forming edge is, with knitting in the pile thread, in stitches of the basic fabric chosen such that an extending of the previously knitted pile loops is possible until the subsequent course is knitted for producing a firm stitch construction, as is above explained with respect to the effect of delayed cutting. With tucking in the pile threads this is also advantageous in order to counteract pulling out of the pile loops, though not always necessary; rather in this example the distance from the pile forming edge to the cutting edge can be reduced to the extent that the cutting can be effected immediately after formation of the pile loop to be cut. In all embodiments, however, the space where a fine machine cut is desired is chosen so that cutting of the cutting is effected below the dial needles, so that the mutual cut of the machine does not need to be increased for the integrated cutting feature.
As to the length of the cutting edge, it is to be observed that each pile loop is severed as soon as it slides within the axial extent of the cutting edge of the pile and the cooperative cutting element and the cutting motion is effected. A substantial length of the cutting edge results to a safety factor to operating faults in the example where the cutting projection is affected by wear, as an uncut pile loop can slide along the cutting edge and is presented in the same position several times under the condition of the cooperating cutting edges. Alternatively, to produce the desired control, cutting can be executed intermittently since knitting a plurality of courses with a corresponding number of pile loops having accumulated on the cutting edge of the pile forming element, so that the safety factor referred to can be partly waived in favor of a reduction in the number of cutting strokes.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be further explained with reference to the embodiments shown in the drawings.
FIG. 1 a partial section through a circular knitting machine according to the invention is simplified, schematic form illustrating a first embodiment of a pile element with a cutting member, in side elevation,
FIG. 2 a view like FIG. 1 in a different operating position of the pile and cutting element,
FIG. 3 a diagram showing the movement of the needles, the pile elements and cutting elements in a possible mode of operation of the knitting machine of FIGS. 1 and 2, in which the curves correspond to the cam tracks controlling the needles, pile elements and cutting members,
FIG. 4 another embodiment of the invention in a view substantially corresponding to FIGS. 1 and 2,
FIG. 5 a section on the line V--V of FIG. 4,
FIG. 6 is a section on the line VI--VI of FIG. 4 illustrating at the same time an alternative embodiment of the arrangement of the cutting edges, in which the position of the needles is shown in dashed lines,
FIG. 7 a view like FIG. 4 in another operating position of the knitting machine,
FIG. 8 a diagram like FIG. 3 showing the movements of the needles, pile elements and cutting elements of the embodiment shown in FIGS. 4 to 7 in one possible mode of operation,
FIG. 9 a modified pile forming element in a view like that of FIG. 5,
FIG. 10 another modification of the pile forming element in a view like that of FIG. 9,
FIG. 11 a side view of the embodiment of FIG. 10
FIG. 12 a view like FIG. 1 of a fifth embodiment of the invention, and
FIG. 13 a fourth embodiment of the invention in a view like that of FIG. 12.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As is seen in FIGS. 1 and 2, a circular knitting machine according to the invention has the usual cylinder Z, in which pile elements 1 are positioned, as well as a dial R, not shown in FIGS. 1 and 2 but shown in FIGS. 4, 12 and 13, in which needles N, shown as ordinary latch needles, are arranged for horizontal by a cooperating cam.
As is apparent from FIGS. 4 and 7, a knitted fabric G is produced from the needles N and taken down, in the direction of arrow W shown there, on the inside of the pile elements 1 and the cylinder Z in the longitudinal direction of pile elements 1. The pile elements 1 with their pile forming hooks formed as cooperate with dial needles N by their retraction simultaneously to stitch formation at a position as shown schematically in FIG. 2 to produce pile loops H on the outside of the knitted fabric G, in known manner.
In the embodiment of FIGS. 1 and 2, a pile loop H is formed, as shown schematically in FIG. 2, at a pile forming edge 1a formed as a draw-hook, and shown in the retracted position of the pile elements 1 in FIG. 2. After the previous knock-over of the needles N the pile element 1 is then extended to the position shown in FIG. 1, in which the thus formed pile loop H, held down by the fabric and the simultaneously projected needles N slips downwards over an extending bulge 1b on the shank of the pile element 1 and rests there. A previously formed pile loop H slips down further the shank of pile element and comes in contact with a cutting edge 1c arranged vertically on the pile element 1 and spaced a distance from the pile forming edge 1a. The loop that contacts cutting edge 1c is severed as will be further explained below. Thus the fabric is released from the pile elements 1 and can pull in and be drawn down further in the direction of the fabric take down W.
As is apparent from FIG. 1, the dial needles N are arranged with corresponding spacing X 1 above the upper end of cutting elements 2. The pile elements 1 in the slots of the cylinder Z can be raised if desired by a cooperating jack M of a known selection device. In particular, the vertical movement of the pile elements 1 is actuated by corresponding cams 3 on a butt 1d.
Associated with each pile element 1, is a cutting element 2, which is arranged in the same plane as the pile element 1, but radially outwardly thereof same in the same slot of the cylinder Z. Each cutting element 2 has a shaft 2a, which has the same thickness as pile element 1. At its upper end, the cutting member 2 has a cutting blade 2b with a cooperating cutting edge 2c, which in a manner to be further explained below is positioned so as to be operative together with cutting edge 1c of pile element 1 and cooperates therewith. The cutting blade 2b is bent away from the plane of shaft 2a by a projection 2d and is therefore arranged laterally adjacent pile element 1 in the region of its cutting edge 1c. If pile element 1 is retracted, as shown in FIG. 2, cutting element 2 pivots outwardly together with its cutting blade 2b and thus over the slot indicated at FK. In this way the cutting blade 2b is positioned either in the FIG. 1 position above the cylinder, or in the FIG. 2 position radially outside the cylinder and the slot FK. Thus the breadth of the slot simply has to correspond to the thickness of the pile element 1 or the shaft 2a of the cutting element 2 respectively.
To effect the pivotal motion of the cutting element 2 it is pivotally arranged by a connecting head 1e on the shank of pile element 1 and a cooperating recess 2e in the shank of cutting element 2. Recess 2e includes circular bearing surface, against which head 1e is received and is thus vertically movable together with pile element 1. Horizontal pressure cams 4 and 5 operate against butts 2f and 2g of the cutting element 2 in order to pivot the cutting element 2 at will, to and fro between the positions shown in FIGS. 1 and 2.
The cooperating cutting edge 2c on cutting blade 2b is inclined outwardly and also at a skew with respect to the cutting edge 1c of the pile element 1, as will be further explained below with reference to FIGS. 4 to 7, so that when cutting edge 2c passes cutting edge 1c by movement of the cutting blade 2b out of the FIG. 2 position and into the FIG. 1 position, in a scissor-like manner, an exclusively point contact is maintained under the counter-pressure, which assures a clean severing of the pile loop H in the area of the cuttoing edges 1c and 2c. Since the force required for severing is effected by pressure on butts 2f and 2g of the cutting element 2, no tension in the pile loop is required.
For stitch formation the needles N and the pile elements 1 are extended. Advantageously, the pile elements 1 may be extended previously, in order to prevent movement of the fabric G and the dial needles N by friction. The pile elements 1 are extended so far that they penetrate through the pile loop H with bulge 1b rising movement of fabric G being restrained by take-down tension acting in direction of arrow W. When the needles N are fully extended, pile elements 1 are retracted to the feeding position so that the pile loop H lying on the bulge 1b eventually expanding the pile thread within the stitch on the needle and thus tightens the pile thread on the needle shaft. Previously formed pile loops H are transported down by continuously knitting of the fabric and arrive in the area of the cutting edge 1c arranged at a position vertically downwardly on the pile element a distance a from the pile forming region 1a. Now the cutting pivot action of the cutting element 2 is effected by cam 4 pressing the butt 2f of the cutting element 2, so that the opposed cutting edge 2c rocks or slides along the cutting edge 1c. As a result the pile loops H lying in this area are cut. In this way, the fabric G is cleared from pile elements 1 and can pull in and further be taken down in the direction of the fabric take down W. FIG. 1 shows the situation at the end of the cutting stroke of cutting element 2. By maintaining a space a between pile forming edge 1a and the cutting edge 1c of each pile element 1, the cutting edges 1c and 2c are so arranged by a predetermined space X 1 that at least the pile loops H of the previously knitted two courses remain uncut and extended on the pile element 2. In this way, the subsequent reprotruding of stitches knitted from the pile thread is prevented. During the severing process the needles N are retracted to the feeding position. As is possible with rib machines, base (i.e. ground) and pile threads can be fed simultaneously, whereupon the needles N and pile elements 1 are retracted to the FIG. 2 position. Prior the retraction of the pile elements 1, cutting element 2 had to be pivoted by a cam 5 pressing the butt 2g into the FIG. 2 position, so that it is possible, with a cylinder extending as far as possible to the dial, to cover the pile elements 1 adequately preventing the cutting blade 2b to be engaged from slot FK.
Possibilities to produce a patterned fabric results by arranging a known per se patterning device to select pile elements 1 to form pile loops H and/or, in, retracting them to different extents. The present embodiment has the advantage that a cutting stroke of the cutting element is only effected when a pile loop H has been formed, so that unnecessary cutting strokes are avoided, if the cutting element remain unselected and a pressure to butt 2f of the cutting element 2 is not effected by cam 4. Since the severing of a pile loop is effected when a number of subsequent courses are knitted, a pile element 1 may remain unselected only in a limited number of courses, or severing must be ensured by predetermined systems in which all pile elements 1, but no needles N, are extended, so there is a sufficiently frequent cutting of the pile loops H.
In order to avoid this limitation, or additional cutting systems needles N can be actuated as seen in FIG. 3 on curve NV. The pile elements 1 with the cutting elements 2 are arranged axially thereon on curve V and the cutting strokes of the cutting element 2 are shown on curve VIa, whereas curve Va illustrates the position of the cutting edge 1c, which is constant in the radial direction. As described above, all pile elements 1 are fully extended and subsequently retracted to reprotrude previously enlarged stitches. A selection device retracts pile elements 1 not selected for forming pile loops on curve Vs simultaneously with the termination of the cutting stroke. Pile thread is fed to the pile elements 1 remaining extended and to the needles N retracted to the feeding position pile thread being fed by feeder FP and the base thread by feeder FG, whereon the needles N and the pile elements 1, the latter on curve Vp, are retracted. In this operational sequence an unlimited arrangement of pile loops H is possible while cutting strokes are effected in every feeder position system where a stitch is formed.
Instead of connecting the cutting element 2 to the pile element 1 by means of its connecting head 1e in the axial direction, it is also possible to position the cutting element 2 in a sliding manner on pile element 1 so it always remaining at the same level. In this arrangement only pivoting movement is required for severing and the cutting blade 2b always remains above the cylinder Z.
In the illustrated embodiment this is achieved by having the cutting element 2 arranged on the radially outer edge of the shank of the pile element 1 in the same slot FK. Alternatively, the shank of pile element 1 could also be widened so that it projects out of slot FK, adjacent ones of such shanks forming slots themselves in which the shanks 2a of the cutting elements 2 can be arranged, without requiring any widening of slots FK circumferentially of the cylinder which would result to coarser cut.
An important advantage of the described for shanks 1a and 2a is that even in fine cuts, extremely rigid and large pile elements 1 and cutting elements 2 can be used. In a cut, if desired an arrangement of the two elements side by side with corresponding widening of the slot FK is practicable.
By knitting the fabric in the dial, fabric G is taken down parallel to the pile elements 1. This requires no further auxilary means to transport the pile loops H gradually from the pile forming edge 1a downwards to the area of the cutting edge 1c. Based on the amount of the space X 1 from the cutting edge 1c 2c to the backs of the needles N located in the dial and corresponding to the pile forming edge 1a and depending also on the course density the number of courses which have to be knit to transport the pile loops H to the cutting area can be determined. As the pile loops H cannot clear from the pile element 1, before being cut and while held at least temporarily extended a correct plating of base and pile threads and therefore a desired jersey side of the fabric is ensured.
The described embodiment requires, on account of the illustrated arrangement of the cutting element 2, a very long sized pile element 1 and relatively complicated caming control not only of the pile element 1 but also of the cutting element 2. Since a vertical movement of the cutting element 2 is not required cutting element 2 can be arranged outside the cylinder, as sinker normally are in an outside dial ring such as a sinker ring.
Such an arrangement is shown in FIGS. 4 to 7. Since the arrangement of a sinker ring and the corresponding cam attachment with respect to the cylinder Z is generally known, these two parts are not shown in detail, to improve the clarity of the drawing but a sinker ring S and the corresponding cam attachment SC is schematically illustrated in FIGS. 4, 7 and 12.
In the embodiment of FIGS. 4 to 7, the same reference numerals are used for corresponding parts as in the embodiment of FIGS. 1 and 2, but increased by 10. Thus in this case the pile element 11 has a pile forming portion 11a formed as a hook, an extending bulge 11b and a cutting edge 11c. The cutting element 12 has a shank 12a, here positioned in slots of the sinker ring S a cutting blade 12b and a cutting edge 12c, and is actuated by cams SC through butt 12f. For an exactly lateral sliding of the cutting element 2 in the embodiment of FIGS. 1 and 2, a projection 1h, is provided on the cutting element 2 in the area of the cutting blade 2b in each of its pivotal positions, so that it is not lifted or pushed off by the skew angle of the cooperating cutting edge 2c. In the embodiment of FIGS. 4 to 7, a projection 12h, shown in FIGS. 4 and 7, is arranged on the cutting element 12. When the cutting element 12 is retracted, projection 12h ensures the desired lateral position of cutting element 12 relative to pile element 11 thereby assuring that the cutting edges 11c and 12c slide properly relative to each other.
Also in the FIGS. 4 to 7 embodiment, pile elements 11 are actuated vertically either by a butt--not shown--or by a selection device. Additionally, sinker ring S is arranged so that the cutting elements are positioned in place of sinkers and are either extended or retracted horizontally by the butt 12f. Cooperating with camming SC the forward end of the cutting element 12 with the cooperating cutting edge 12c can be completely or partially inclined toward the axis of pile element 11, in order to have an angle of inclination or a skew angle β shown in FIG. 5. In the embodiment of FIGS. 4, 5 and 7, cutting element 12 is made plane or flat and arranged in the sinker ring S so as to form an angle of inclination or a skew angle β with corresponding slots of the sinker ring. The embodiment illustrated in FIG. 6, differs in that the shanks 12a of the cutting element 12 are vertically positioned in their width or height direction in the sinker ring S, but the cutting blades 12b are correspondingly skewed with respect to the plane of shank 12a and projection 12h, as is readily apparent from the plan view of cutting member 12 in FIG. 6. The cooperating cutting edge 12c always makes an offset angle α with respect to cutting edge 11c, as seen in FIG. 4. In this way, mutual contact is produced between the cutting portion of the pile element and the cooperating cutting edge of cutting element only at one moving or varying point, as is known in the art of making scissors, so that definite cutting conditions always apply, and the cutting edges can sharpen each other. In the embodiment of FIG. 6, the cutting elements 12 are positioned with their widthwise extension vertically in the sinker ring S, but slightly inclined in the circumferential direction, differing therefore from the radial orientation of the needles shown in phantom lines, so as to facilitate a resilient contact of the cutting elements 12 on the corresponding pile elements 11, the elastic deformations under this contact pressure and hence the amount of contact pressure is adjustable by circumferential adjustment of the position entire sinker ring S.
The knitting of pile loops H is effected as described in the embodiments of FIGS. 1 and 2. After forming (knock over of) the knitted course, as seen from FIG. 4, the pile elements 11 and needles N are projected. The raising of the pile elements 11 effects a lengthening of the pile loops when these loops pass over extending bulges 11b so that when the stitches clear the latches on the the needle shanks they will appear as enlarged stitches. While the needles are retracted to the feeding position, the cutting stroke is effected by actuating the cutting elements 12 on butt 12f by a corresponding cam SC as seen in FIG. 7. Simultaneously to the feeding of base and pile thread in front of and behind the pile element 11, the cutting element 12 is retracted. Successively needles N and the pile elements 11 are fully retracted for stitch and pile loop formation, as illustrated in FIG. 4. By a spaced arrangement X 2 of the cutting elements 12 beneath the needles N it is ensured that at least the pile loop H of the previously knitted course remain uncut. In knitting patterned fabrics, the pile elements 11, needles N and the cutting elements 12 are all preferably actuated corresponding to the motion curve referred to in accordance with FIG. 3.
Alternatively, another possible actuation curve is shown in FIG. 8, where the pile loops are knitted in as tuck stitches, with this occurring in the following manner. In the embodiment according to FIGS. 4 to 7 a portion of the needles N are moved along curve N1 and all pile elements 11 move along curve V. Since in tuck stitching the pile loop H must not be extended subsequently the cutting element 12 can be arranged with such a small distance X 2 below the backs of the needles N that the pile loops H are cut after they are formed by the successive cutting projection. If desired, the pile elements 11 not selected for engaging the pile thread P are then retracted on curve Vs, while the needles N are further extended to the position required for pile loop formation. The pile thread P is fed to the further extended pile elements 11 by feeder FP, whereupon these are retracted on curve Vp for loop formation. As soon as the hooks of the pile elements 11 pass the needles N, at least a portion of the needles remaining in the miss position will raise on curve N2 into the knit position or on curve N3 into the tuck position. Preselected needles can remain on curve N4 in the miss position. After all extended needles N are retracted to the feeding position, feeder FG feeds the base thread. Then all needles are retracted for stitch formation (or moved to their knock over position).
While, for the production of unpatterned (plain) cut pile fabric, a selection of the pile elements 11 is not required, an arrangement of the pile elements M fixedly in the cylinder, in a similar way, as will be detailed below in accordance with the embodiment of FIGS. 12 and 13 is possible. The pile elements then project with a pile forming portion stationary between the extended needles N in the dial R. The difference in height of the pile forming portion of the pile elements for knitting the pile loops and the knock-over edge of the dial for knitting the base fabric determines the length of the pile loops H. By using pile elements with pile forming portions having different heights relative to the dial variations in the pile height or loop lengths can be effected by selection or preselected insertion of the different pile elements. For the production of plain fabrics this arrangement has the advantage that no cylinder caming is required to actuate the pile elements.
Since the pile loops are only cut when at least a subsequent course has been knitted, the cutting process is substantially, and with fixed pile elements, absolutely independent from the knitting process. With vertical-movable pile elements 1 or 11, on the contrary, the stroke of the cutting elements 2 or 12 should occure when the pile elements 1 or 11, will not be actuated, (i.e. should occur preferably in their miss or extended position).
As explained in accordance with the embodiment of FIGS. 1 and 2, if the pile elements 1 or 11, are selected a cutting process is required at least after knitting a number of subsequent courses. Analogous to this, if all pile elements and cutting elements generally are actuated to the cutting process, only to predetermined feeders or systems of the knitting machine a cutting action of the cutting elements is required. In this way, the abrasion of the cutting edges is reduced.
Since in knitting in the pile loops H as tuck stitches, advantageously only a portion of the pile elements are raised in a fixed order at consecutive feeders, advantageously a cutting action can also be effected with only a corresponding portion of the cutting elements in the same or a predetermined sequence. This also results in a decrease amount of abrasion of the cutting edges. In this way it is also possible to arrange a smaller number of pile elements and cutting elements than there are knitting needles. Thus if pile loops are knitted in from every fourth needle only and this is centered at subsequent feeders, whereby every second needle never is raised to form pile loops, only a half of the pile elements 1 or 11 and cutting elements 2 or 12 must be positioned in the cylinder and the sinker ring. Thus, if it should be desired that only half as many slots are required, these can be wider whereby even stronger pile elements and cutting elements can be arranged.
In the embodiments described, the pile loops H will be formed around pile elements 1 or 11 tightly so that, if there is a failure in the severing operation through poor contact of the cutting edges. If the forming is too tight between the contact of the pile loop to the pile element, the cooperating cutting edges 2c or 12c can be deflected away from the cutting edges 2c or 11c by the pile loops H. This can be prevented if the pile loop as a result of a suitable shape of the contact face of the pile element 1 or 11 does not wind around at the position of the cutting edges 1c or 11c.
In FIGS. 9 to 11 are illustrated two embodiments, in which the pile elements 21 or 31 are formed in a bicomponent manner in the area of the cutting edges 21c or 31c where the cooperating cutting edge of the cutting elements 22c or 32 pass between the two portions of the pile element.
Also in these two embodiments, and in the later embodiments, the same reference numerals are used for corresponding parts, but increased by 10.
In the embodiment of FIG. 9 the pile element 21 includes two individual portions which are positioned side by side with their surfaces facing each other. These comprise a massive portion 21f, and a thin portion 21g which lies over it in side elevation, which is not shown. Both portions 21f and 21g are so shaped in the area where the cutting element 22 with the cooperating cutting edge 22c will pass between both portions. For example, portion 21f is reduced in thickness, as at 21b, and portion 21g cranked, so that the cutting element 22 can be flexibly pressed on the cutting edge 21c and can be guided between the portions 21f and 21g. As a result of the skewness of the cutting blade 22b, the cutting element 22, when passing through the opening between the portions 21f and 21g, is deflected and also bends out the thin portion 21g. On that account it is advantageous if the portion 21g is sprung into contact with or resiliently pressed onto the massive portion 21f. In the axial region of the cutting edge 21c, the thin, resilient portion 21g is radially set back from the cutting edge 21c with respect to the cylinder axis, in order to prevent a jamming of the pile loop in the cutting action on the right hand side of the cutting element 22 as seen in FIG. 9. The pile loop passes across the slot 21h and is not twisted round the face of the cutting edge 21c, but is held away therefrom by the portion 21g, so that favorable cutting conditions are obtained and jamming of the pile thread between the cutting edges 21c and 22c and a bad cut is avoided.
In the embodiment of the pile element 31 of FIGS. 10 and 11 the pile element 31 is formed almost completely from the portion 31f, and the sprung or resilient portion 31g is connected to the upper flank of portion 31f between the cutting edge 31c and the pile forming portion 31a, but merely sprung or resiliently pressed against it below the cutting edge 31c. In this way too great a formation of the pile loop is avoided, without obstructing the movement of the cooperating cutting edge 32c and the cutting element 32. The extending of previously formed pile loops is effected by the wavy form of the upper part of the pile element 31 shown at 31b.
As seen in FIG. 11, the forward edge of the portion 31g is somewhat set back from cutting edge 31c of the component 31f here, as already explained in accordance with the embodiment of FIG. 9, in order to hold the pile loops over the opening 31h and spaced away from cutting edge 31c, and to avoid a jamming of the cut end of the pile loop on the portion 31g on the side of the cutting edge 31c.
In FIGS. 12 and 13, finally, pile elements 41 and 51 are shown which are not actuated vertically or operate like the pile elements which have already been referred to in accordance with the embodiment of FIGS. 4 to 7 as an alternative arrangement without vertical movement. In order that the lengths of the pile loops can be altered quickly, pile elements 41 and 51 are pivotally supported on pivots 41e and 51e. In this way, the formation of longer pile loops is effected more quickly, because the needles N and the pile elements 41 and 51, have simultaneous movements in opposite directions, the movement of the pile elements 41 and 51 is adjustable.
In the embodiment according to FIG. 12, the pile element 41 is provided with a component 41g, corresponding to the previous features of FIGS. 10 and 11, and radially slidable with a projection 41h in a slot of the cylinder Z. The pile element 41 is held in position by a ring 9. The pile element 41 projects downwardly with a butt 41f out of the slot in the cylinder Z. The butt 41f is running in a track formed by cam 8a and 8b. The cams 8a and 8b are secured on a movable carrier 8c. By adjusting the carrier 8c, the cams 8a and 8b control a variable pivotal movement of the pile element 41. In this way an adjustable pivotal movement of the pile elements 41 and therefore an adjustment of the loop length of the pile loops can be realized.
The pile element 51 of FIG. 13 is pivotable in the cylinder Z, about a pivot point 51e and has an additional butt 51d by means of which pile elements 51 can be moved in their lengthwise direction. Further butts 51f and 51'f cooperate with pressing cams described in accordance with FIG. 1 and FIG. 2 which pivot the pile element 51 into the desired position for pile formation. If the pile elements 51 have predetermined butts 51d of different heights or differently arranged, such different pile elements 51 can be inserted and, can be raised to different, levels. Therefore butts 51'f are also selected at different heights. On each selection, differently acting pressing cams can form different lengths of pile loops in the same course. The selection of the pile elements 51 can also be effected by a known per se selection device. In this embodiment there is the additional advantage, with regard to the prior art known from West German Pat. No. 1,935,224 (FIGS. 5 and 6) or West German Pat. No. 656,588, that the loop length is not fixed by different shaped edges of the pile elements 51 to all systems or all feeders, but can be adjusted as desired at each feeder. Moreover selected pile elements 51 can be so effected to different heights that the production of patterened loop and cut pile fabric is possible.
In the foregoing description reference numerals which have not been referred to although shown in the drawings are correlated with correspondingly lower reference numerals in the manner described, and thus further features are illustrated in the drawings that can be provided identically or analogously in the different embodiments. In this regard therefore the description will suffice in order to avoid repetition of the explanation of the different embodiments with regard to similar or analogous embodiments. | A circular knitting machine for the production of cut pile has latch needles (N) in the dial (R) and pile elements (11) in the cylinder (Z). Each pile element has an upper pile forming portion (11a) for example shaped like a hook, and also, spaced substantially therebelow, a cutting edge (11c) which cooperates with an opposed separate cutting edge (12c) of a cutting element (12). Cutting is effected thereby in the direction transverse to the axis of the cylinder (Z). Pile loops (H) are pulled downwardly by the fabric take down (arrow W) from the pile forming portion (11a) to the cutting edge (11c) sufficient time being available, before they are cut, to extend the pile loops (H) as desired and to tension the needle stitches over the just formed pile loops (H). The opposed cutting edge (12c) can be angled or skewed with respect to the cutting edge (11c) so that even with fine gauges, a real scissor action is guaranteed with only point contact of the cutters. Fine gauges are not excluded on account of the fact that the opposed cutting edges (12c) operate neither in the slot for the pile elements in the cylinder (Z) nor in the area of the needles (N). | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to apparatus for preparing foods and beverages and, more particularly, to spit or impaling-type cookers.
BACKGROUND OF THE INVENTION
[0002] Barbecuing whole chickens upon upright and open beverage containers formed of aluminum has become a rage. By partially filling the beverage containers with liquids such as beer or wine, the chickens are basted from the inside out as heat from barbeque grills cause the liquids to vaporize and fill the interior cavities of the chickens. Not only do the liquid vapors impart a nice flavor to the cooked chicken meat but such also prevent the meat from drying out. Chicken cooked in this manner is nearly always perfect.
[0003] Keeping chickens oriented in an upright manner on beverage containers has proven to be something of a tricky problem. Chickens, unfortunately, are not evenly balanced. Furthermore, typical beverage containers have a bottom with a surface area of only a few square inches which is not nearly enough to solidly support a chicken. Thus, light bumps to grills can tip over and spoil chickens perfectly balanced on beverage containers. Some have proposed implements that essentially expand the surface area at the bottom of a beverage container to make such less prone to tipping over, but these implements have not seen widespread use because of their complex and cumbersome natures.
SUMMARY OF THE INVENTION
[0004] In light of the problems associated with the known implements for cooking chickens upon beverage containers, it is a principal object of the invention to provide a poultry cooking device that will effectively support a chicken impaled upon an upright beverage container that is uncomplicated in its construction, is intuitive to use, and is inexpensive to manufacture. The device can be used in association with: a barbecue grill, an oven, a stovetop, or an open fire.
[0005] It is another object of the invention to provide a poultry cooking device of the type described that is formed by cutting and bending a single metallic sheet. The device is lightweight, virtually unbreakable and durable enough to withstand repeated use.
[0006] It is a further object of the invention to provide a poultry cooking device of the type described that can be employed to simultaneously cook a pair of chickens on an outdoor barbecue grill. If desired, each chicken can be internally basted with a different liquid.
[0007] Still another object of the invention is to provide a poultry cooking device of the type described that channels poultry drippings onto a heat source such as barbecue briquettes during the cooking process to minimize the effort required to clean-up the device after use and to enhance the barbecue flavor imparted to the poultry by generating smoke. Simultaneously, the device directs heat and smoke to the one or more chickens that it supports for even cooking.
[0008] It is a further object of the invention to provide a poultry cooking device of the type described that can be employed to easily carry one or more chickens to and from a grill. Once on the grill, the device can be easily moved about to optimally cook one or more chickens.
[0009] Briefly, the poultry cooking device in accordance with this invention achieves the intended objects by featuring a plate having a number of apertures therein. The apertures have inner ends that are positioned closely adjacent to one another and outer ends that are positioned remote from one another. The inner ends of the apertures define a closed geometric form. Additionally, a number of fingers extend upwardly from the plate, with a respective one of the fingers being secured to the plate at the inner end of each of the apertures.
[0010] The foregoing and other objects, features and advantages of the present invention will become readily apparent upon further review of the following detailed description of the preferred embodiment as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The present invention may be more readily described with reference to the accompanying drawings, in which:
[0012] FIG. 1 is a perspective view of a poultry cooking device in accordance with the present invention.
[0013] FIG. 2 is a side elevational view of the poultry cooking device of FIG. 1 with portions broken away to reveal details thereof and, also, supporting a beverage container upon which a chicken is impaled.
[0014] FIG. 3 is a top view of the poultry cooking device.
[0015] FIG. 4 is a top view of the blank used to form a poultry cooking device.
[0016] Similar reference characters denote corresponding features consistently throughout the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Referring now to the FIGS., a poultry cooking device in accordance with the present invention is shown at 10 . Device 10 includes a plate 12 having a pair of container keepers 14 positioned along the length thereof. Each keeper 14 has number of upstanding fingers 16 spaced from one another so as to snugly, yet releasably, receive the bottom of a beverage container 18 . Adjacent each of the fingers 16 is an aperture 20 that permits heated air to pass upwardly to a chicken 22 impaled on container 18 and, also, allows any juices flowing from chicken 22 to drain downwardly through plate 12 .
[0018] Plate 12 is rectangular in outline and is sufficiently sized to steadily support a pair of containers 18 upon which a pair of chickens 22 is impaled. To bear such a load, plate 12 is reinforced around its periphery by longitudinal and lateral fins 24 and 26 . As shown, a pair of longitudinal fins 24 is secured to the front and back of plate 12 with each of longitudinal fins 24 extending downwardly from plate 12 . A pair of lateral fins 26 , however, is secured to the opposite sides of plate 12 with each of lateral fins 26 extending upwardly and outwardly from plate 12 . To permit device 10 to be more easily grasped and carried, an outwardly extending tab 28 , oriented substantially parallel to plate 12 , is secured to the outer end of each of lateral fins 26 . Thus, each lateral fin 26 and its associated tab 28 serves as a handle for device 10 .
[0019] A hole 30 is placed in one of lateral fins 26 so as to permit device 10 to be suspended from a support (not shown) for convenient storage when not in use.
[0020] Each container keeper 14 includes four fingers 16 arrayed such that their linear bottoms define an imaginary square “A,” i.e., a closed geometric form, whose sides have a length that is substantially equivalent to the diameter of container 18 and are inclined about 45° to the sides of plate 12 . This configuration permits fingers 16 to be made, as will be more fully described below, relatively large in size and without substantially weakening plate 12 . Of course, the number of fingers 16 provided to each keeper 14 is largely a matter of design choice with any number of fingers 16 capable of retaining a container 18 atop plate 12 being suitable.
[0021] Each finger 16 is substantially flat and triangular in outline, being wide at its bottom and tapering to a narrowed top for enhanced rigidity and strength. The bottom of each finger 16 has a length that is about one-half of the diameter of container 18 . The height of each finger 16 is about one-half of the height of container 18 . Due to the relatively large dimensions of each finger 16 , it is very difficult to dislodge a container 18 from a keeper 14 with a sideways below even while the container 18 is supporting a chicken 22 . Always, container 18 must be elevated a substantial portion of its height above plate 12 to remove such from the grasp of fingers 16 .
[0022] An aperture 20 is positioned adjacent to each one of the fingers 16 and extends outwardly from each keeper 14 . Each aperture 20 is triangular in outline, having substantially the same shape as the finger 16 that borders such at its inner end. As shown, each aperture 20 is wide at its inner end and tapers to a narrowed outer end to ensure that the principal flow of air through plate 12 will take place immediately adjacent to each keeper 14 to speed the cooking of chicken 22 .
[0023] Device 10 is formed by cutting and folding portions of a planar blank 32 formed from a single piece of sheet metal. First, fingers 16 are made by cutting a plurality of V-shaped notches 34 at suitable locations in blank 32 and, then, folding the material within notches 34 to an upright position along retainer fold lines 36 that “close” the open ends of notches 34 . It is the voids left within notches 34 by the production of fingers 16 that form apertures 20 . Next, the boundaries of plate 12 are defined by folding longitudinal fins 24 downwardly along longitudinal fold lines 38 at the front and back of plate 12 and further defined by folding lateral fins 26 upwardly along lateral fold lines 40 . Finally, tabs 28 are provided to device 10 by folding the outer ends of lateral fins 26 downwardly along handle fold lines 42 .
[0024] The use of device 10 is straightforward. First, one or a pair of open containers 18 are partially filled with a liquid such as beer, wine or water. Then, the bottoms of containers 18 are fitted within keeper 14 , fingers 16 holding containers 18 firmly atop plate 12 . Next, one or a pair of previously cleaned chickens 22 are impaled upon containers 18 so that such appear to be seated upon plate 12 . Afterward, device 10 is placed within a barbecue grill or oven (not shown) and chickens 22 are cooked until done. Any juices flowing from chickens 22 will pass through apertures 20 to a heat source within the grill or oven and produce smoke that will impart an appealing flavor to chickens 22 . Heated air and smoke from a heat source will flow upwardly through apertures 20 , cooking chickens 22 rapidly and flavorfully. Simultaneously, the liquid within containers 18 will boil and fill chickens 22 with moisture, thereby basting chickens 22 from their interior during cooking.
[0025] Once chickens 22 are fully cooked, device 10 is lifted from the barbecue grill or oven by grasping tabs 28 . Chickens 22 are, then, removed from containers 18 and carved, served and consumed in a conventional manner. Later, after being permitted to cool down, containers 18 are withdrawn from keepers 14 and discarded. Finally, device 10 is washed with soap and water and, by means of hole 30 , suspended from a support to dry and to be reused when desired.
[0026] While the invention has been described with a high degree of particularity, it will be appreciated by those skilled in the art that modifications may be made thereto. Therefore, it is to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims. | A poultry cooking device including a metal plate having a plurality of fingers partially cut therefrom. The fingers are folded such that they extend upwardly from the metal plate and leave a plurality of apertures in the metal plate when moved from their original positions. The fingers are located about the metal plate such that they define a keeper for snugly receiving a beverage container upon which a chicken can be impaled and cooked. The apertures are positioned around the keeper to hasten cooking and enhance flavor. | 0 |
BACKGROUND OF THE INVENTION
The present invention generally relates to a dust-sucking cleaner hose for use in a vacuum cleaner, and particularly relates to a cleaner hose in which a strength-holding reinforcing wire rod and a conductive wire for current conduction are provided so as to be spirally wound in the inside of a hose body.
Conventionally, a cleaner hose of this kind has such a structure that, as generally known, a pair of coated wires, one being a steel wire acting as a reinforcing wire and the other being a conductive wire for current conduction which are integrally coated with resin, are spirally wound and a hose body is fitted onto the outer circumference of the thus spirally wound coated wires and connected through adhesive to the coated wires, so that the shape of the hose body is held by the reinforcing wire and the conductive wire is connected to a switch at hand for turning a power source of a vacuum cleaner on/off in use. Further, known is a cleaner hose having such a structure that a hose body is constituted by double layers and a coated wire constituted by a steel wire acting as a reinforcing wire and an electric wire for current conduction which are integrally coated with each other, is spirally buried between the double layers so that an electric operation is performed by using this electric wire.
In those conventionally generally known cleaner hoses, however, the steel wire and the electric wire are integrally covered with coating resin. In the case of the former hose, the whole upper surface of the coated wire is connected through an adhesive to the hose body. In the case of the latter hose, on the other hand, the coated wire is packed in between the double layers of the hose body so as to be bonded to the hose body.
Thus, when the electric wire is taken out of the hose body so as to be connected to a switch at hand or an insertion plug to a vacuum cleaner body, the separation of the coated wire from the hose body requires much trouble and the separation of the electric wire from the steel wire also requires much trouble.
That is, in the hose in either case, only a portion of the hose body is cut off and the coated wire at the end portion of the hose body is left intact by a length of the hose body necessary for taking out the electric wire. Then, the cut hose body portion is gradually separated from the coated wire portion to thereby take out the coated wire. Thereafter, the coated wire portion is cut at an intermediate portion between the steel wire and the electric wire to thereby separate the steel wire and the electric wire from each other. Then, the steel wire is cut at a position near the above-mentioned cut end portion of the hose body to thereby take out the independent coated electric wire at last.
In the conventional hoses, therefore, there is a serious problem that a long time and difficult operations are required to take out the coated electric wire. Moreover, there is an economical problem in that, since it is necessary to cut off the hose body by a length required for taking-out the electric wire at each of the opposite ends of the hose body, it is necessary to previously prepare the hose so that it is elongated enough by a length to be cut off.
SUMMARY OF THE INVENTION
The present invention has been therefore made to solve the above various problems in the conventional cleaner hoses, and has an object to provide a cleaner hose in which a coated wire comprising a reinforcing wire rod acting as a strengthening member and a conductive wire for current conduction has a special structure so that the coated electric wire can be easily torn off and separated from a coating portion of the reinforcing wire rod, and the adhesion connection between the coated wire and the hose body has a special structure so that the coated conductive wire can be easily separated from the hose body and the connection between the hose body and a switch at hand or the like can be extremely easily performed in a short time.
According to the present invention, the cleaner hose includes a coated wire comprises by a reinforcing wire rod for holding strength and a conductive wire for current conduction, which are separated at an interval and are integrally coated with a synthetic resin raw material in the inside of the hose, wherein the coated wire has such a structure that a coating portion of the reinforcing wire rod and a coating portion of the conductive wire are connected to each other through a thin connection portion which can be torn off, and only the coating portion of the reinforcing wire rod is connected through an adhesive to an inner surface of a hose body.
The thin connection portion between the respective coating portions of the reinforcing wire rod and the conductive wire may be disposed in any position, for example, in the position on the axial line side of the hose body, in the position along the inner surface of the hose body, in the intermediate position between the above-mentioned two positions, etc., so long as the connection portion can be easily separated by tearing.
In view of easiness in spiral winding of the coated wire, it is preferable that the coated wire is connected to the hose body in a laterally turned posture (that is, in such a posture that the reinforcing wire rod and the conductive wire are put side by side in the longitudinal direction of the hose body). Alternatively, the coated wire may be connected to the hose body in a standing posture, that is, in such a posture that the reinforcing wire rod is located on the hose body side and the conductive wire is located on the axial line side of the hose body.
Further, the coated wire is not limited to a wire in which a reinforcing wire rod and a conductive wire are coated as a pair, but the coated wire may be configured such that a reinforcing wire rod and two conductive wires are coated as a pair.
The present invention has such a structure as described above, that is, such a structure that the coating portion of the conductive wire is made so as to be easily torn off from the coating portion of the reinforcing wire rod and is made not to be bonded with the hose body. Therefore, the coated conductive wire can be immediately pulled out of the end portion of the hose body while being torn off and separated from the coating portion of the reinforcing wire rod, and the conductive wire thus pulled out of the hose body to the outside by the pull-out operation can be immediately connected to a required portion such as a switch at hand only through an operation to remove the coating of the pulled-out conductive wire at its end portion by a required length.
In the cleaner hose according to the present invention, therefore, it is not necessary to unnecessarily elongate the whole length of the hose but the hose may be prepared so as to have only the required length from the first, the conductive wire taking-out work can be extremely easily performed, and the connection of the conductive wire to an electric connection portion such as a switch at hand or a connection plug attached on an instrument to be connected to each of the opposite ends of the hose body can be easily performed in a short time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially broken sectional view showing a part of the outline of a hose according to a first embodiment of the present invention,
FIG. 2 is a sectional view showing a pipe wall of the hose shown in FIG. 1,
FIG. 3 is an enlarged sectional view showing the pipe wall of the hose shown in FIG. 1,
FIG. 4 is a perspective view showing a using state of the hose shown in FIG. 1,
FIG. 5 is an enlarged sectional view showing a pipe wall portion of a hose of a second embodiment,
FIG. 6 is an enlarged sectional view showing a pipe wall portion of a hose of a third embodiment,
FIG. 7 is an enlarged sectional view showing a pipe wall portion of a hose of a fourth embodiment,
FIG. 8 is an enlarged sectional view showing a pipe wall portion of a hose of a fifth embodiment,
FIG. 9(a) is an enlarged sectional view showing a coated wire having one conductive wire of a sixth embodiment, and
FIG. 9(b) is an enlarged sectional view showing a coated wire having two conductive wires of a seventh embodiment.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the accompanying drawings, preferred embodiments of the present invention will be described.
FIGS. 1 through 4 show a first embodiment of the present invention. FIG. 1 shows a partially broken exterior shape of a cleaner hose H, FIG. 2 is an enlarged view showing the structure of a pipe wall portion, FIG. 3 is an explanatory view showing a further enlarged portion of FIG. 2, and FIG. 4 is a view showing a state where a conductive wire is taken out.
A coated wire A shown in the drawings of this embodiment has a structure in which a reinforcing wire rod 1 formed by using a steel wire rod and a conductive wire 2 formed by bundling-up a large number of thin copper wires are circularly coated with a polyvinyl chloride raw material so that the section is formed into like "glasses" and that the reinforcing wire rod 1 and the conductive wire 2 are separated at a small interval from each other but integrally connected to each other through a thin connection portion c at a one-sided position so that an outside line d between the reinforcing wire rod 1 and the conductive wire 2 is made substantially linear.
Further, the hose H of this embodiment has such a structure as follows. That is, a pair of such coated wires A and A' with a required interval are spirally wound in parallel with the respective connection portions c put downside. After an adhesive 4 is applied only to an upper surface of a coating portion a of each of the reinforcing wire rods 1, a belt-like raw material of polyvinyl chloride for forming a hose wall is wound so as to extend over the outer peripheral surface of the coated wire A or A' and the gap portion between the coated wires A and A', and adjacent portions of the belt-like raw material are connected to each other so that a hose body 3 is formed and at the same time the belt-like raw material is connected to the coated wires A and A' by the adhesive 4.
Further, in the hose H, the belt-like raw material is partially thicken and each of the thus formed thicker portions is disposed in the gap between the coated wires A and A', so that the hose wall thicker than the upper surface portion of each of the coated wires A and A' is formed in the gap between the coated wires A and A' and that the inner surface of the hose wall disposed in each gap between the coated wires A and A' and the outside line d (the lower surface portion) of each of the coated wires A and A' are made to be substantially even to each other.
In a hose body 3 shown in FIG. 3, the hose wall has a structure of a two-layered wall constituted by inner and outer layers 3a and 3b. Reference numeral 5 designates a boundary between the inner and outer layers and simultaneously designates a reinforcing thread interposed in the longitudinal direction of the hose between the outer and inner layers. The hose H according to the present invention can be realized as a hose having a hose wall constituted by two layers as described above and as a hose in which, besides the reinforcing thread, any reinforcing member such as a fibrous reinforcing member or a mesh-like reinforcing member is interposed between two layers.
For the sake of easily grasping the size of the hose H in this embodiment, the dimensions of the various portions shown in the drawings of this embodiment will be roughly described in the following example. The diameter of the reinforcing wire rod 1 is 1.0 mm, the diameter of the coating portion a of the reinforcing wire rod 1 is 2.35 mm, the conductive wire 2 is constituted by 7 wires each having a diameter of 0.18 mm, the diameter of the coating portion b of the conductive wire 2 is 1.45 mm, the thickness of the connection portion c is 0.45 mm, the distance between the respective center lines of the reinforcing wire rod 1 and the conductive wire 2 is 2.00 mm, the distance between the respective center lines of the reinforcing wire rods 1 and 1 is 10.0 mm, the thickness of the hose body inner layer 3a at its portion covering the coated wire A in FIG. 3 is 0.35 mm, the thickness of the hose body inner layer 3a at its portion between the coated wires A and A' in FIG. 3 is 0.70 mm, the thickness of the hose body outer layer 3b in FIG. 3 is 0.25 mm, and the inner and outer diameters of the hose body 3 are 37.5 mm and 44.0 mm respectively.
In the thus formed cleaner hose, the conductive wire 2 with the coating portion b can be immediately pulled out of the hose body 3 from the end portion of the hose body 3 while being torn off and separated from the coating portion a of the reinforcing wire rod 1, as shown in FIG. 4. Therefore, the conductive wire 2 pulled out of the hose body 3 to the outside by the pull-out operation as described above can be immediately connected to a required portion such as a switch at hand through only such an ordinary operation that the coating d of the end portion of the conductive wire 2 is removed by a required length.
Further, in the hose shown in this embodiment, the portion between the coated wires A and A is formed to have a thicker wall portion so that the hose can be used without such an inconvenience that the hose shrinks by a suction operation in use. Moreover, the hose has an advantage in that it can be easily used because of its light weight in comparison with a hose in which the whole hose body is formed to have a thick wall.
FIGS. 5 through 7 show other embodiments of the coated wire A. In a second embodiment shown in FIG. 5, a coated wire A having the same sectional shape as that shown in the above-mentioned first embodiment is disposed upside down to the case of the first embodiment so that a thin connection portion c is placed at the outer peripheral surface side. Adhesion to a hose body 3 is made in a manner so that only the upper surface of a coating portion a of a reinforcing wire rod 1 is made to adhere to the hose body 3 through an adhesive 4 in the same manner as in the first embodiment.
In a third embodiment shown in FIG. 6, a thin connection portion c of a coated wire A is formed at an intermediate portion in the up/down direction in the drawing between a coating portion a of a reinforcing wire rod 1 and a coating portion b of a conductive wire 2. In a fourth embodiment of FIG. 7, a thin connection portion c of a coated wire A is formed at each of upper and lower portions in the drawing between a coating portion a of a reinforcing wire rod 1 and a coating portion b of a conductive wire 2 so that a hollow portion is formed at an intermediate portion between the connection portions c. Portions other than the above-mentioned portions are the same as those in the first embodiment.
Although the coated wire A in each of the foregoing embodiments is formed by coating a reinforcing wire rod 1 and a conductive wire 2 as a pair, a fifth embodiment shown in FIG. 8 shows a coated wire A in which a reinforcing wire rod and two conductive wires are coated as a pair. In this embodiment of FIG. 8, in a coated wire A having the same sectional shape as that shown in the first embodiment, another conductive wire 2 is additionally provided so that the two conductive wires 2 are disposed symmetrically with respect to the reinforcing wire rod 1 on the right/left sides thereof. Also in this case, the adhesion to a hose body 3 is made in a manner so that only an upper surface of a coating portion a of the reinforcing wire rod 1 is made to adhere to the hose body 3 through an adhesive 4 in the same manner as in the first embodiment.
Embodiments shown in FIG. 9 show a coated wire A in which a reinforcing wire rod 1 and a conductive wire 2 are vertically disposed. FIG. 9(a) shows the structure of the coated wire A in which a reinforcing wire rod 1 is located at the hose body 3 side and a conductive wire 2 is located at the axial line side of the hose body 3, and FIG. 9(b) shows the structure of the coated wire A in which two conductive wire 2 and 2 are located below a reinforcing wire rod 1 and right and left sides respectively. The coated wire A according to the present invention may be realized in such a structure.
In the case of the coated wire A in which a reinforcing wire rod 1 and two conductive wire 2 are coated as a pair as shown in the embodiments of FIG. 8 and FIG. 9(b), even a hose in which only one coated wire A is wound on the hose body 3 can be used for operating a switch at hand or the like. Further, in such a hose in which two coated wires A are wound, one of the coated wires A can be used for a switch at hand for turning the cleaner body per se on/off while the other coated wire A can be used for turning a suction portion set rotary body provided at a front end of an operation pipe.
Although description has been made as to the embodiments which are considered to be representative of the present invention, the present invention is not limited to the structures of those embodiments. The present invention may be suitably modified and carried out within a scope in which the foregoing constituent features of the present invention are provided and the objects of the present invention are attained, and effects which will be described later are obtained.
As apparent from the foregoing description, according to the present invention, the coated wire has such a structure that the respective coating portions of the reinforcing wire rod and conductive wire are connected to each other through the thin connection portion which can be torn off, and the adhesion connection between the coated wire and the hose body has such a structure that only the coating portion of the reinforcing wire rod is connected through adhesive to the inner surface of the hose body so that the coating portion of the conductive wire is easily torn off from the coating portion of the reinforcing wire rod and the coating portion of the conductive wire does not adhere to the hose body. It has therefore been obtained such a remarkable effect that the coated conductive wire can be immediately pulled out of the hose body from its end portion while being torn off and separated from the coating portion of the reinforcing wire rod and the conductive wire pulled out of the hose body to the outside by the pull-out operation as described above can be immediately connected to a required portion such as a switch at hand through only such an operation that the coating portion of the pulled-out conductive wire is peeled at its end portion by a length required for connection.
Further, in the hose according to the present invention, it is not necessary to make the whole length of the hose longer by a length required for removing the conductive wire, and therefore the hose can be made so as to have a length required for normal use. Conductive wire removal operations can be performed extremely easily, and connection of the conductive wire to an electric connection portion such as a switch at hand or a connection plug attached on the devices to be connected to the opposite ends of the hose body can be easily performed in an extremely short time. Therefore, the production cost of the unit can be greatly reduced. | A cleaner hose with a built-in current conduction wire includes a reinforcing wire rod for holding strength and a conductive wire for current conduction, which are spirally wound in the inside of a hose body, and further includes a coated wire constituted by the reinforcing wire rod and the conductive wire built in the hose. The reinforcing wire rod and the conductive wire are separated at an interval and are integrally coated with a synthetic resin raw material at an interval. A coating portion of the reinforcing wire rod and a coating portion of the conductive wire are connected to each other through a thin connection portion which can be torn off, and only the coating portion of the reinforcing wire rod is connected through an adhesive to an inner surface of the hose body. | 0 |
FIELD OF THE INVENTION
This invention describes a new process for obtaining strains of Penicillium chrysogenum with greater penicillin G production capacity, by the introduction and expression in the control strain of an exogenous gene which codes for the enzyme phenylacetyl-CoA ligase and which originates from the bacterium Pseudomonas putida.
PRIOR ART
The pathway for biosynthesis of benzylpenicillin (penicillin G) in Penicillium chrysogenum is a linear and branched metabolic pathway which leads on one side to the amino acid L -lysine and on the other to the said antibiotic (see FIG. 1 ).
The penicillins-specific branch begins with the non-ribosomal condensation of three amino acids ( L -α-aminoadipic, L -cysteine and L -valine), giving rise to a linear tripeptide ( L -α-aminoadipyl- L -cysteinyl- D -valine), also called ACV, which lacks antibacterial activity (Ref. 1). The enzyme which catalyses this conversion is L -α-aminoadipyl- L -cysteinyl- D -valine synthetase, which in abbreviated form is called ACVS (Ref. 2). In a subsequent step the tripeptide ACV is converted to isopenicillin N (IPN) by the cyclization of the L -cysteine and D -valine residues (Ref. 3). This reaction leads to the synthesis of a molecule which has two rings, β-lactam and thiazole, and in which the remainder of the L -α-aminoadipic acid remains as a side chain (FIG. 1, Ref. 3). IPN is the first molecule in the pathway which has antibacterial activity, although its potency against G-organisms is poor. The enzyme responsible for synthesis of this compound is isopenicillin N synthetase (IPNS) (Ref. 3). In a subsequent stage (see FIG. 1) Penicillium chrysogenum replaces the remainder of the L -α-aminoadipic acid present in the IPN with phenylacetic acid, giving rise to a molecule which keeps the β-lactam and thiazole rings but which now has phenylacetic acid as a side chain. This penicillin, called penicillin G or benzylpenicillin, has a greater potency than IPN and a much broader antibacterial spectrum.
The final stage of penicillin G biosynthesis requires at least three different enzymatic reactions. First, the phenylacetic acid has to be incorporated from the culture medium into the cell. This step is catalyzes by a specific transport system referred to by the abbreviation PTS (FIG. 1) (Ref. 4). Next, the phenylacetic acid is activated to phenylacetyl-CoA (PA-CoA) by a mechanism, not well known, which appears to require the involvement of a phenylacetyl-CoA-ligase (PCL). Finally, the PA-COA is used by the enzyme acyl-CoA:6-aminopenicillanic acid (isopenicillin N) acyltransferase (AT) (Ref. 5), in such a way that this protein catalyzes the acylation of the 6-amino group of the 6-aminopenicillanic acid (6-APA) or else the interchange between the remainder of the L -α-aminoadipic acid present in the IPN molecule and phenylacetyl-CoA, releasing the products penicillin G and CoA in the first case (when the substrates are 6-APA and phenylacetyl-CoA) and penicillin G, CoA and L -α-aminoadipic acid in the second case (when the substrates are IPN and PA-COA) (Ref. 6).
The biochemical and genetic studies carried out to date (Ref. 5) have allowed all he enzymes of the penicillin G specific biosynthetic pathway to be identified and their genes to be characterized, with the exception of the enzyme phenylacetyl-CoA ligase, which it has not been possible to purify and the gene of which is unknown at the moment. In addition, the amounts of the different biosynthetic enzymes (ACVS, IPNS and AT) detected in different strains of Penicillium chrysogenum (both in those whose production of penicillin G is low and in other strains used industrially) are sufficiently high to eliminate the possibility of any of them being considered a limiting stage in the biosynthesis of penicillin G (Ref. 7-8). For this reason a study was commenced of the enzyme phenylacetyl-CoA ligase (PCL), the only enzyme in the pathway for which the sequence is not fully known. The absence of detectable amounts of enzyme in all the strains of Penicillium chrysogenum studied means that different microorganisms have to be selected for their ability to grow in a medium of defined composition (minimal medium, MM) containing phenylacetic acid (PA) as the sole carbon source (Ref. 9), and also that the existence of phenylacetyl-CoA ligase activity has to be assessed in all the selected strains. Of all the microorganisms isolated, a strain of Pseudomonas putida U was selected which breaks down phenylacetic acid aerobically by means of an undescribed degradation pathway involving a new enzyme: phenylacetyl-CoA ligase (EC 6.2.1.30). This enzyme was purified to homogeneity and characterized biochemically (Ref. 9). The Pseudomonas putida U enzyme, which we will hereinafter call PLC, presents some optimal physicochemical conditions which are very similar to the IPNS and AT of Penicillium chrysogenum, and so it was thought that the three enzymes could work together in vitro. It was shown that the PCL of Pseudomonas putida U and the IPNS and AT of Penicillium chrysogenum could be linked in vitro and used in this form for the production of both penicillin G and other penicillins in the laboratory (Ref. 10). These results, which are described in Spanish Patents Nos. P8902421 and 2016476 A6, allowed the possibility to be suggested that the PCL of Pseudomonas putida U might be expressed in Penicillium chrysogenum and that, if this enzyme was a limiting stage in the biosynthetic pathway, greater production of penicillin G might be achieved.
DESCRIPTION OF THE INVENTION
1. Isolation of the gene which codes for the enzyme phenylacetyl-CoA ligase in Pseudomonas putida U
The strain of Pseudomonas putida U, which had phenylacetyl-CoA ligase activity when grown in the MM described in Ref. 9, was mutated by the insertion of the transposon Tn5 (Ref. 11), as is detailed in the protocol shown in FIG. 2 . The strains which were unable to break down phenylacetic acid were selected, which suggested that the insertion had occurred in one of the genes, or intergenic regions, corresponding to the catabolic pathway of this aromatic compound. In all the mutants PCL activity was assayed as described in Spanish Patent P8902421 and in the corresponding publication (Ref. 9). For this purpose the various mutants were grown in the same MM, but it now contained, as carbon sources, 4-hydroxyphenylacetic acid (4-OHPA), which does not induce PCL, and phenylacetic acid (PA), which, although it cannot be broken down, could induce PCL (Ref. 12). In this MM the 4-OHPA is used by the bacteria to sustain cell growth whereas the PA acts as an inducer of the enzyme phenylacetyl-CoA ligase.
By this simple procedure the various mutants were characterized in such a way that two groups could be established:
a) those which possessed functional PCL (called PCL+) and in which the transposon Tn5 had thus inserted itself into a gene on the pathway (or into an intergenic region) after the gene coding for PCL, and
b) the others in which this activity could not be detected (called PCL−).
The absence of PCL in this second group of mutants could be due to two reasons:
1) it could be due to the fact that the transposon had inserted itself in front of the gene coding for the ligase (pcl) (if, as was suspected, all the catabolic pathway responsible for the breakdown of PA is under the control of one promoter), or it could be due to the fact that
2) the Tn5 had incorporated itself into the pcl gene itself, or into a regulator gene or sequence.
From one of the mutants in which no PCL activity was detected, called E 1 , the insertion of Tn5 was identified by the use of oligonucleotide sequences which were exactly the same as the ends of Tn5 (5′ D 3′: ACT TGT GTA TAA GAG TCA G SEQ ID NO:13) and which had been radioactively labelled. The zone of the E 1 mutant genome linked to the transposon was cloned in the plasmid pUC 18 and the Escherichia coli strain D5α′ was transformed in accordance with the conventional protocols (Ref. 13). The insert was then sequenced and the gene which hybridized with the gene sequence isolated from the mutant E 1 , and which corresponded to the adjacent zone of the transposon, was searched for in a Pseudomonas putida U DNA library produced in the phage λ EMBL4. Of all the phages which gave positive hybridization, three which contained 13, 15 and 18 Kb fragments of the genomic DNA of Pseudomonas putida were selected. From one of these, the one which contained a 13 Kb insert, DNA was extracted (Ref. 13), it was cleaved with the restriction enzyme EcoRI, and a 10 Kb fragment was selected. When this fragment of Escherichia coli DH5α′ was introduced, using the plasmid pUC 18 as transformation vector, the presence of the insert gave the latter bacterium the ability to grow in MM which contained PA as the sole carbon source. Growth was slower, however, than that observed in Pseudomonas putida U—which suggested that although it contained genes which made catabolism of this compound possible, its breakdown rate in Escherichia coli was much slower. This effect could be due either to the fact that (i) a gene (or genes) needed for total breakdown of PA is (are) missing or incomplete in the fragment—which would force the bacterium to replace it (them) with another one (or others) present in its own genome, so as to allow it to use the accumulated catabolite, albeit more slowly; or to the fact that (ii) despite all the required genes being present in the fragment, the toxicity caused by PA (or by one of its breakdown products) prevented more effective utilization of this compound in Escherichia coli. In addition, it was shown that those bacteria ( Escherichia coli DH5α′) which did not contain the plasmid pUC 18+insert, or others which only had the plasmid pUC 18 without the 10 Kb insert, were unable to grow in MM+PA as sole carbon source—which clearly demonstrates that (i) the catabolism of phenylacetic acid was essentially due to the expression of the genes included in the 10 Kb fragment and (ii) the Escherichia coli strain used (DH5α′) did not have any functional enzymes enabling it to grow in MMs which contained PA as the sole carbon source. It was subsequently confirmed that this fragment contained the pcl gene, as considerable phenylacetyl-CoA ligase activity was detected in cell-free extracts of Escherichia coli DH5α′, whereas not even basal levels of the said activity were detected in the same bacteria without pUC 18+insert, or in others which only had pUC 18.
Subsequent studies allowed a more discrete fragment (2090 base pairs) to be obtained which, cloned in pUC 18, coded for a protein with PCL activity, and the restriction analysis of which is given in detail in FIG. 3 . The nucleotide sequence of the pcl gene was called SEQ ID NO:1.
The amino acid sequence of the protein coded for by this gene was called SEQ ID NO:2. The determination of ligase activity was carried out as described in Ref. 9, but now starting with cell-free extracts of Escherichia coli which had grown in LB medium (see Luria-Bertani in Ref. 13), supplemented with 100 μg/ml of the antibiotic ampicillin (in those cases where cells containing the gene which coded for the β-lactamase present in the plasmid pUC 18 were being analyzed) or in the absence of the antibiotic, if the cells did not contain the plasmid. In all cases the bacteria were collected when the absorbance (Abs 540 nm ) of the culture diluted 1/10 was 0.2. Under these conditions the proportion of PCL present in the extracts free of those cells which contained the insert carrying the pcl gene was 23% relative to total protein. All the oligopeptides obtained by analysis of the amino terminal of the protein previously purified from Pseudomonas putida U were found in this sequence, as well as the others obtained by tryptic digestion of the same enzyme. This protein presents a consensus sequence (SSGTTGKP SEQ ID NO:14) which corresponds to an AMP binding site (Ref. 14-15). In addition, the enzyme was purified from the Escherichia coli DH5α′ strain which had been transformed with pUC 18+the insert indicated in FIG. 3, it being possible to show that: (i) the protein expressed had the same molecular weight as that obtained from Pseudomonas putida U; and (ii) that this enzyme could also be linked to the IPNS and AT of Penicillium chrysogenum, giving in vitro synthesis of penicillin G.
When expression in Escherichia coli DH5α′ using the plasmid pUC 19 as vector was employed, however, PCL activity was not detected—which suggests either that the Pseudomonas putida U promoters are not expressed in Escherichia coli or that there are no promoter sequences in the DNA fragment available.
Subsequent studies carried out to shorten the fragment shown in FIG. 3 by digesting it with the enzymes exonuclease III/nuclease S1 (using the Erase-a-base system supplied by the PROMEGA company) (Ref. 16) allowed a clone Bal116 (SEQ ID NO: 8) to be obtained which had lost a sequence fragment (in front of the one coding for PCL) but which, however, kept the same amino terminal sequence as the PCL purified from Pseudomonas putida U (MNMYH). Analysis of the different gene sequences obtained when the fragment of 2090 base pairs was digested with exonuclease III/nuclease Si (Erase-a-base system) (Ref. 16) for different periods of time suggested that the expression of these DNA fragments in Escherichia coli could lead to different PCLs in which only the amino terminal sequence changed. Analysis of the PCL activity expressed in Escherichia coli (TABLE I) revealed that the amino terminal end of the native protein (MNMYH), corresponding both to that purified from Pseudomonas putida U and to that encoded by the clone Bal116, could change without any appreciable variation in enzymatic activity. Thus, the clone Bal112 (SEQ ID NO: 7), which codes for a PCL with a longer amino terminal end (MTMITNSSNSSEAMNM SEQ ID NO:15), kept the same activity as that expressed from the clone Bal116. The same happened when a study was made of the activity of the proteins expressed by the clones Bal142 (SEQ ID NO: 10) and Bal101 (SEQ ID NO: 3), the amino terminals of which had been considerably reduced (MTMITNSRYH (SEQ ID NO:16) and MTMITNSSDA (SEQ ID NO:17), respectively). From the clone Bal110 (SEQ ID NO: 6) a protein was obtained the amino terminal of which (MTMITNSSWRAAYKNNSSEAMNMYH SEQ ID NO:18) was longer than that encoded by the construct corresponding to Bal112 due to the presence of an internal WRAAYKN (SEQ ID NO:19) sequence. This protein did not exhibit any PCL activity—which shows that although it is possible to introduce certain modifications into the amino terminal end of the protein without changing the activity, others, such as the one described, lead to non-functional enzymes in spite of keeping the complete sequence of the native protein. This result is particularly interesting as it shows that, provided that the MTM sequence belonging to the pUC 18 polylinker exists, the PCL cloned in Escherichia coil is not expressed from its own ATG. With the aim of establishing the importance of the two methionines present in the polylinker (MTM) use was made of a variant of pUC 18 in which a deletion of one of the two cytosines located between the two ATGs of the plasmid had occurred and which consequently gave rise to a STOP signal. The sequence in this mutated plasmid is called SEQ ID NO: 11. The loss of this C produces a reading frame shift such that the protein would only be able to start in the second methionine. Using this vector a study was made of the expression of a construct which did not have any of the nucleotide sequences coding for the two methionines present in the amino terminal end of the native PCL, which is the case with the construct Ball42. Analysis of the PCL expressed revealed that a functional protein was produced, showing that the second ATG of the polylinker marks the beginning of the PCL cloned.
In those other constructs, created in the original plasmid zUC 18, in which there were stop signals in the three reading frames, the different PCLs start to synthesize from the amino terminal of the native protein (this is the case with the clones Bal106—SEQ ID NO: 4-, Bal107—SEQ ID NO: 5-, Bal116 and Bal117—SEQ ID NO; 9-).
All these data allowed the conclusions to be drawn that:
a) the gene cloned corresponds to the one which codes for the enzyme PCL in Pseudomonas putida U
b) the expression of this protein in Escherichia coli DH5α′ is governed by the promoter of β-galactosidase present in the plasmid pUC 18, and that
c) discrete modifications to the amino terminal sequence lead to functional PCLs, whereas introduction of the amino acid sequence WRAAYKN (SEQ ID NO:19(Bal112) causes total loss of phenylacetyl-CoA ligase activity.
2. Expression of the Pseudomonas putida U gene in the mold Penicillium chrysogenum
Once the pcl gene of Pseudomonas putida U had been characterized, the next objective was to introduce it into Penicillium chrysogenum with the aim of determining whether its expression in this mold resulted directly in the production of a greater quantity of penicillin G.
Penicillium chrysogenum Wis 54-1255 was chosen as the control strain. Usng the procedure described by Sanchez et al. (Ref. 17-18), protoplasts were obtained from mycelium that had grown in minimal medium. The protoplasts were transformed (17-18) with a plasmid derived from pBC (Stratagene), which contained a gene for resistance to the antibiotic phleomycin (Ref. 19), the promoter of the gene pcb AB, the ACVS of Penicillium chrysogenum (Ref. 19), the pcl gene of Pseudomonas putida U (starting from the construct indicated as Bal101) and the terminator of the trpC gene of Penicillium chrysogenum. The construct, called pALPs9 (FIG. 4 ), was produced as follows: A 1.2 Kb fragment NcoI, the ends of which were filled with Flenow (Ref. 13), was obtained from the plasmid pALP498, carrying a 2316 pb fragment BamHI which includes the bidirectional promoter pcbAB-pcbC (P pcbAB, see Ref. 19). This fragment was bound with Bal101, which had previously been digested with EcoRI, filled with Klenow and dephosphorylated, giving rise to insertions in both directions which were called pALPs1 and pALPs2. The clone pALPsI contains the pcl gene under the control of the promoter pcbAB. By digestion of this plasmid with XbaI, filling of the ends with Klenow and subsequent digestion with HindIII, a 2.8 Kb fragment with romo-HindIII ends was obtained which contained the pcbAB promoter-pcl gene complex. This fragment was subcloned in the fungal transformation vector pALfleo digested with XhoI, filled with Klenow and finally digested with HindIII. The plasmid obtained, which had the pcbAB promoter-pcl complex inserted in the same direction as the phleomycin resistance cassette (ble r ), was called pALPs8. Finally, a 725 pb fragment was introduced which includes the terminator of the trpC gene (TtrpC) of Penicillium chrysogenum in the EcoRV site of pALPs8, located between the pcl gene and the phleomycin resistance cassette. The construct bearing the trpC terminator, in the correct orientation, was called pALPs9 and used for expression of the pcl gene in different strains of Penicillium chrysogenum. This construct is shown in FIG. 4 .
The transformant strains of Penicillium chrysogenum, which expressed the phleomycin resistance gene (ble r ), were selected (Ref. 19) and analyzed. All the transformants selected carried the pcl gene, as is shown by the fact that when amplification by PCR (polymerase chain reaction) was carried out, using the DNA of the different transformants and 2 internal oligonucleotides corresponding to the pcl gene, the respective sequences of which were: 5′ D 3′: ATC TGG GEC GGG AAC AC (SEQ ID NO:20) and GGC GCA AGG GEG ACA A (SEQ ID NO:21), amplified fragments of a size equivalent to that expected (651 base pairs) were obtained in all cases (FIG. 5 ). Amplification was not observed, however, either in the untransformed control strain or in that transformed with a construct in which the pcl gene had been eliminated (FIG. 5 ), which shows that (i) this same gene does not exist in the genome of Penicillium chrysogenum and (ii) there are not any similar sequences which could be amplified. 98% of the phleomycin-resistant transformants analyzed contained the pcl insert.
In order to complete this study, four transformants and an untransformed control were selected and both the expression of the gene (appearance of phenylacetyl-CoA ligase activity in cell-free extracts) and its effect on benzylpenicillin production were analyzed. For studies of this type the control and the transformants selected were inoculated in plates of complete production medium, the composition of which, in g/l, is as follows: corn steep solid 30, lactose 30, phenylacetic acid 1, agar 20 g and distilled water up to 1 l. The pH was adjusted to 6.5 with NaOH (30% w/v) and 10 g of CaCO 3 were then added. After it had been prepared, the medium was sterilized at 121° C. for 30 min and divided up at the rate of 30 ml per Petri dish of 9 cm diameter. The dishes were inoculated with the spores collected from the different colonies and were incubated at 25° C. for 9 days. At this point in time 10 ml of sterile H 2 O per dish were added and the spores of each of the transformants were collected. These strains were used to inoculate an inoculation medium which contained, in corn steep solid 20, sucrose 20 and soluble maize distillates (DDS) 20. The pH of the medium was adjusted to 5.7 and 5 g of CaCO 3 were then added. The medium was distributed into 250-mi Erlenmeyer flasks containing 50 ml of the medium described. The flasks were sterilized in an autoclave at 121° C. for 30 min, and after cooling they were inoculated with 1 ml of a spore suspension containing 10 9 spores/ml. The flasks were incubated at 25° C. in a Gallenkamp orbital shaker at 230 rpm for 24 h. 2.5-ml aliquots of this culture were then used to inoculate each 250-ml Erlenmeyer flask which contained 30 ml of complete production medium (without agar), prepared as described earlier. The fermentations were carried out for 56 h, taking aliquots at different times in order to determine the amount of penicillin produced, the dry weight (mg/ml) and the presence or absence of PCL in the different strains studied. The mycelium was collected by filtration, washed with 2000 volumes of sterile distilled H 2 O and dried with filter paper, and 1.5-g aliquots of wet mycelium (equivalent to 600 mg of dry weight) were resuspended in 0.5 M phosphate buffer solution, pH 8.0, containing 1 mM phenylmethylsulphonylfluoride (PMSF), and it was immediately disrupted by sonication. The extracts were centrifuged to eliminate the unbroken cells and the cell walls, and the supernatant was used to estimate phenylacetyl-CoA ligase activity. The procedure followed was the one employed for analysis of the enzyme in Pseudomonas putida, as we described earlier (see Ref. 9 and Spanish Patent P8902421). The formation of phenylacetyl-CoA (PA-CoA) was monitored by HPLC, using a high-pressure liquid chromatograph consisting of a Waters 600 pump, a Waters 481 detector, a 10 μm Nucleosil C18 column (250×4.6 mm), a Wisp 717 automatic injector and a Waters computer system (Millenium 2010). The injection volume was 50 μl. 0.2 M potassium phosphate, pH 4.5/isopropanol (90:10 vol/vol) was used as the mobile phase. The flow rate was 1 ml/min and the wavelength selected was 254 nm. Under these conditions PA-CoA has a retention time of 19.30 min and phenylacetic acid (PA) a retention time of 10.8 min. Analysis of the various transformants revealed that phenylacetyl-CoA ligase activity was detected in all of them, whereas this did not appear in the control (see Table II), which indicated that the pcl gene of Pseudomonas putida U was being expressed in Penicillium chrysogenum . The transformants thus obtained were deposited in the Spanish Standard Cultures Collection, where they were given the registration number CECT 20192.
The amount of penicillin G accumulated in the culture media was estimated by HPLC, using equipment consisting of a Waters 510 pump, a Varian 2050 detector, a 5-μm Hypersil ODS column (100×4.6 mm) and a Wisp 717 automatic injector. The injection volume was 20 μl. 0.05 M ammonium acetate, pH 6.8/methanol (60:40 vol/vol) was used as the mobile phase. The flow rate was 0.8 ml/min and the wavelength chosen was 235 nm. Under these conditions the retention time of penicillin G is 4.5 min. As can be seen in Table II, all the transformants produced between 84% and 121% more penicillin G than the control strain, which irrefutably demons-rates that the expression of the pcl of Pseudomonas putida I in Penicillium chrysogenum helps to increase penicillin G synthesis considerably in this mould.
BFIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 Pathway for biosynthesis of penicillin G (benzylpenicillin) in Penicillium chrysogenum
FIG. 2 Diagram of the protocol of mutagenesis with the transposon Tn5. Rif: rifampicin 20 μg/ml; Km: kanamycin 25 μg/ml; PA: phenylacetic acid; Fru: fructose; M9: minimal medium with a composition as described in Reference 13.
1 Mixing stage
2 Centrifugation for 3 min at 12000 rpm
3 Precipitate of Escherichia coli+Pseudomonas putida, 40 μl of which is collected and deposited in a filter on a dish with LB medium (Reference 13)
4 Dilution
5 Selection
A Mutants
FIG. 3 pcl gene of intact Pseudomonas
FIG. 4 pcl gene of Pseudomonas expressed under the control of the promoter of the pcbAB gene of Penicillium chrysogenum
FIG. 5 Amplification of part of the sequence of the pcl gene, using the oligonucleotides indicated in the report as initiators. (1) Pseudomonas putida U; (2) Escherichia coli +pUC18+2090 pb insert (see report); (3) Escherichia coli +pUC18 (without insert); (4) Penicillium chrysogenum Wis 54-1255 control; (5 to 8) Different CECT20192 transformants of Penicillium chrysogenum which contain the pcl gene in the construct pALPs9; (9) Transformants of Penicillium chrysogenum Wis 54-1255 containing a construct similar to pALPs9 without the pcl gene.
REFERENCES
1. Fawcett, P. and Abraham, E. P. (1975). In Methods in Enzymol. Ed., J. H. Hash, Vol. 43, pp. 471-473, Academic Press, New York.
2. Aharonowitz, Y.; Bergmayer, J., Cantoral, J. M., Cohen, G., Demain, A. L., Flnk, U., Kinghorn, J., Kleinkauf, H., MacCabe, A., Palissa, H., Pfeifer, E., Schweck, T., van Liempt, H., von Dohren, H., Wolfe, S., and Zhang, J. (1993). Bio/Technology 11:807-810.
3. Baldwin, J. E. and Bradley, M. (1990). Chem. Rev. 90:1079-1088.
4. Fernandez-Cañón, J. M., Reglero, A., Martinez-Blanco, H. and Luengo, J. M. (1989. J. Antibiotics 42:1398-1409.
5. Luengo, J. M. (1995), J. Antibiotics 48: 157-174.
6. Whiteman, P. A., Abraham, E. P., Baldwin, J. E., Fleming, M. D., Schofield, C. J., Sutherland, J. D. and Willis, A. C. (1990). FEBS Lett. 262, 342-344.
7. Barredo, J. L., Diez, B., Alvarez, E. and Martin, J. F. (1989). Curr. Genet 16:453-459.
8. Smith, D. J., Bull, J. H., Edward J. and Turner, G. (1989). Mol.Gen. Genet. 216:492-497.
9. Martinez-Blanco, H., Reglero, A., Rodriguez Aparicio, L. S. and Luengo, J. M. (1990). J. Biol. Chem. 265:7084-7090.
10. Martinez-Blanco, H., Reglero, A. and Luengo, J. M. (1991). J. Antibiotics 44:1252-1258.
11. Selvaraj, G. and Iyer, V. N. (1983). J. Bacteriol. 156:1292-1300.
12. Olivera, E. R., Reglero, A., Martinez-Blanco, H., Fernández-Medarde, A., Moreno, M. A. and Luengo, J. M. (1994) Eur. J. Biochem. 221. 375-381.
13. Sambroock, J., Fritsch, E. F. and Maniatics, T. (1982). In “Molecular cloning, a Laboratory Manual”. Cold Spring Harbor, N.Y.
14. Hori, K., Yamamoto, Y., Tokita, K., Saito, F., Kurotsu, T., Kanda, M., Okamura, K., Furuyama, J. and Saito, Y. (1991) J. Piochem. 110, 111-119.
15. Turgay, K., Krauze, M. and Marahiel, M. A. (199-2). Mol. Microbiol. 6, 529-546.
16. Henikoff, S. (1984). Gene, 28:351-359.
17. Sánchez, E., Rubio, V., Pefalva, M. A. and Perez-Aranda, A. (1987). European Patent Application 0235951B1.
18. Sánchez, E., Lozano, M., Rubio, V. and Peñalva, M. A. (1987). Gene 51, 97-102.
19. Diez, B., Gutiérrez, S., Barredo, J. L., van Solingen, P., van der Voort, L. H. M. and Martin, J. F. (1990). J. Biol. Chem. 265:16358-16365.
TABLE I
SEQUENCE
CLONE
PCL ACTIVITY
SEQ ID NO: 3
BAL101
YES
SEQ ID NO: 4
BAL106
YES
SEQ ID NO: 5
BAL107
YES
SEQ ID NO: 6
BAL110
NO
SEQ ID NO: 7
BAL112
YES
SEQ ID NO: 8
BAL116
YES
SEQ ID NO: 9
BAL117
YES
SEQ ID NO: 10
BAL142
YES
SEQ ID NO: 11
BAL142
YES
(pUC 18 mutant)
21
1
1401
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from pUC18 with
another originating from Pseudomonas corresponding to the pcl
gene.rdp
1
catgacactc accgcgtggc ttgcaaccgc tggcgcgcgg cgtacaagaa caattcgagt 60
gaagcc atg aac atg tac cat gat gcc gac cgt gcc ctg ttg gac ccg 108
Met Asn Met Tyr His Asp Ala Asp Arg Ala Leu Leu Asp Pro
1 5 10
atg gaa acc gcc agt gtc gac gcc ctg cgc cag cac cag ctg gag cgc 156
Met Glu Thr Ala Ser Val Asp Ala Leu Arg Gln His Gln Leu Glu Arg
15 20 25 30
ctg cgc tgg agc ctg aag cac gcc tac gac aat gtg ccg ctg tac cgc 204
Leu Arg Trp Ser Leu Lys His Ala Tyr Asp Asn Val Pro Leu Tyr Arg
35 40 45
cag cgc ttt gcc gaa tgc ggc gcc cac ccc gac gac ctc acg tgc ctg 252
Gln Arg Phe Ala Glu Cys Gly Ala His Pro Asp Asp Leu Thr Cys Leu
50 55 60
gaa gac ctg gcg aag ttc ccc ttc acc ggc aag aac gac ctg cgc gac 300
Glu Asp Leu Ala Lys Phe Pro Phe Thr Gly Lys Asn Asp Leu Arg Asp
65 70 75
aac tac ccc tac ggg atg ttc gcc gtc ccc cag gaa gag gtg gtg cgc 348
Asn Tyr Pro Tyr Gly Met Phe Ala Val Pro Gln Glu Glu Val Val Arg
80 85 90
ctg cat gct tcc agc ggc acc acc ggc aag ccg acg gtg gtc ggt tac 396
Leu His Ala Ser Ser Gly Thr Thr Gly Lys Pro Thr Val Val Gly Tyr
95 100 105 110
acc cag aat gac atc aac acc tgg gcc aat gtc gtg gcg cgc tcg atc 444
Thr Gln Asn Asp Ile Asn Thr Trp Ala Asn Val Val Ala Arg Ser Ile
115 120 125
cgt gcg gcc ggc ggg cgc aag ggt gac aaa gtg cat gtt tcc tac ggc 492
Arg Ala Ala Gly Gly Arg Lys Gly Asp Lys Val His Val Ser Tyr Gly
130 135 140
tat ggg ctt ttc act ggc ggg ctt ggt cgg cac tac ggc gcc gag cgc 540
Tyr Gly Leu Phe Thr Gly Gly Leu Gly Arg His Tyr Gly Ala Glu Arg
145 150 155
ctg ggc tgt acg gta atc ccg atg tcg ggt ggc cag acc gag aag cag 588
Leu Gly Cys Thr Val Ile Pro Met Ser Gly Gly Gln Thr Glu Lys Gln
160 165 170
gtg cag ctg atc cgc gac ttt cag ccc gac atc atc atg gtc aca ccg 636
Val Gln Leu Ile Arg Asp Phe Gln Pro Asp Ile Ile Met Val Thr Pro
175 180 185 190
tcc tac atg ctc aac ctg gcc gac gag atc gag cgc cag ggc atc gac 684
Ser Tyr Met Leu Asn Leu Ala Asp Glu Ile Glu Arg Gln Gly Ile Asp
195 200 205
ccg cat gac ctc aag cta cgc ctg ggc att ttc ggt gcc gaa cct tgg 732
Pro His Asp Leu Lys Leu Arg Leu Gly Ile Phe Gly Ala Glu Pro Trp
210 215 220
acc gat gaa cta cgt cgc tcg atc gag cag cgc ctg ggc atc aat gcc 780
Thr Asp Glu Leu Arg Arg Ser Ile Glu Gln Arg Leu Gly Ile Asn Ala
225 230 235
ctc gac atc tat ggt ttg tcg gaa atc atg ggc ccc ggg gtg gcc atg 828
Leu Asp Ile Tyr Gly Leu Ser Glu Ile Met Gly Pro Gly Val Ala Met
240 245 250
gaa tgc atc gaa acc aag gac ggc ccg acc ata tgg gaa gac cac ttc 876
Glu Cys Ile Glu Thr Lys Asp Gly Pro Thr Ile Trp Glu Asp His Phe
255 260 265 270
tac ccc gaa atc atc gac ccg gtc acc ggc gaa gta ttg cca gac ggt 924
Tyr Pro Glu Ile Ile Asp Pro Val Thr Gly Glu Val Leu Pro Asp Gly
275 280 285
cag ctg ggc gaa ctg gtg ttc acc tcg cta agc aaa gag gcg ctt ccg 972
Gln Leu Gly Glu Leu Val Phe Thr Ser Leu Ser Lys Glu Ala Leu Pro
290 295 300
atg gtg cgc tac cgc acc cgt gac ctc acc cgc ctg ctg ccc ggc acc 1020
Met Val Arg Tyr Arg Thr Arg Asp Leu Thr Arg Leu Leu Pro Gly Thr
305 310 315
gcc agg ccg atg cgg cgg atc ggc aag att acc ggg cgc agt gac gac 1068
Ala Arg Pro Met Arg Arg Ile Gly Lys Ile Thr Gly Arg Ser Asp Asp
320 325 330
atg ctg atc att cgc ggc gtc aac gtg ttc ccg acc cag atc gag gaa 1116
Met Leu Ile Ile Arg Gly Val Asn Val Phe Pro Thr Gln Ile Glu Glu
335 340 345 350
cag gta tta aaa ata aaa cag ctt tcc gag atg tat gag att cat ttg 1164
Gln Val Leu Lys Ile Lys Gln Leu Ser Glu Met Tyr Glu Ile His Leu
355 360 365
tat cgc aat ggc aac ctg gac agc gta gag gtg cat gta gag ttg cgt 1212
Tyr Arg Asn Gly Asn Leu Asp Ser Val Glu Val His Val Glu Leu Arg
370 375 380
gcg gag tgc cag cac ctc gat gaa ggc cag cgc aag ctg gtt atc ggg 1260
Ala Glu Cys Gln His Leu Asp Glu Gly Gln Arg Lys Leu Val Ile Gly
385 390 395
gag ctg agc aaa cag atc aag acc tac atc ggc atc agc acc cag gtg 1308
Glu Leu Ser Lys Gln Ile Lys Thr Tyr Ile Gly Ile Ser Thr Gln Val
400 405 410
cac ctg cag gct tgc ggc acg ctc aag cgt tcc gag ggc aag gcg tgc 1356
His Leu Gln Ala Cys Gly Thr Leu Lys Arg Ser Glu Gly Lys Ala Cys
415 420 425 430
cac gtg tac gac aaa cgg ttg gcc agc tga ttcattcggc tgcct 1401
His Val Tyr Asp Lys Arg Leu Ala Ser
435
2
439
PRT
Pseudomonas
2
Met Asn Met Tyr His Asp Ala Asp Arg Ala Leu Leu Asp Pro Met Glu
1 5 10 15
Thr Ala Ser Val Asp Ala Leu Arg Gln His Gln Leu Glu Arg Leu Arg
20 25 30
Trp Ser Leu Lys His Ala Tyr Asp Asn Val Pro Leu Tyr Arg Gln Arg
35 40 45
Phe Ala Glu Cys Gly Ala His Pro Asp Asp Leu Thr Cys Leu Glu Asp
50 55 60
Leu Ala Lys Phe Pro Phe Thr Gly Lys Asn Asp Leu Arg Asp Asn Tyr
65 70 75 80
Pro Tyr Gly Met Phe Ala Val Pro Gln Glu Glu Val Val Arg Leu His
85 90 95
Ala Ser Ser Gly Thr Thr Gly Lys Pro Thr Val Val Gly Tyr Thr Gln
100 105 110
Asn Asp Ile Asn Thr Trp Ala Asn Val Val Ala Arg Ser Ile Arg Ala
115 120 125
Ala Gly Gly Arg Lys Gly Asp Lys Val His Val Ser Tyr Gly Tyr Gly
130 135 140
Leu Phe Thr Gly Gly Leu Gly Arg His Tyr Gly Ala Glu Arg Leu Gly
145 150 155 160
Cys Thr Val Ile Pro Met Ser Gly Gly Gln Thr Glu Lys Gln Val Gln
165 170 175
Leu Ile Arg Asp Phe Gln Pro Asp Ile Ile Met Val Thr Pro Ser Tyr
180 185 190
Met Leu Asn Leu Ala Asp Glu Ile Glu Arg Gln Gly Ile Asp Pro His
195 200 205
Asp Leu Lys Leu Arg Leu Gly Ile Phe Gly Ala Glu Pro Trp Thr Asp
210 215 220
Glu Leu Arg Arg Ser Ile Glu Gln Arg Leu Gly Ile Asn Ala Leu Asp
225 230 235 240
Ile Tyr Gly Leu Ser Glu Ile Met Gly Pro Gly Val Ala Met Glu Cys
245 250 255
Ile Glu Thr Lys Asp Gly Pro Thr Ile Trp Glu Asp His Phe Tyr Pro
260 265 270
Glu Ile Ile Asp Pro Val Thr Gly Glu Val Leu Pro Asp Gly Gln Leu
275 280 285
Gly Glu Leu Val Phe Thr Ser Leu Ser Lys Glu Ala Leu Pro Met Val
290 295 300
Arg Tyr Arg Thr Arg Asp Leu Thr Arg Leu Leu Pro Gly Thr Ala Arg
305 310 315 320
Pro Met Arg Arg Ile Gly Lys Ile Thr Gly Arg Ser Asp Asp Met Leu
325 330 335
Ile Ile Arg Gly Val Asn Val Phe Pro Thr Gln Ile Glu Glu Gln Val
340 345 350
Leu Lys Ile Lys Gln Leu Ser Glu Met Tyr Glu Ile His Leu Tyr Arg
355 360 365
Asn Gly Asn Leu Asp Ser Val Glu Val His Val Glu Leu Arg Ala Glu
370 375 380
Cys Gln His Leu Asp Glu Gly Gln Arg Lys Leu Val Ile Gly Glu Leu
385 390 395 400
Ser Lys Gln Ile Lys Thr Tyr Ile Gly Ile Ser Thr Gln Val His Leu
405 410 415
Gln Ala Cys Gly Thr Leu Lys Arg Ser Glu Gly Lys Ala Cys His Val
420 425 430
Tyr Asp Lys Arg Leu Ala Ser
435
3
30
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from pUC18 with
another originating from Pseudomonas corresponding to the pci
gene.
3
atgaccatga ttacgaattc gagcgatgcc 30
4
115
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene.
4
atgaccatga ttacgaattc gcagccgtat atgctgcgct catgacactc accgcgtggc 60
ttgcaaccgc tggcgcgcgg cgtacaagaa caattcgagt gaagccatga acatg 115
5
91
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene.
5
atgaccatga ttacgaattc gagctcaccg cgtggcttgc aaccgctggc gcgcggcgta 60
caagaacaat tcgagtgaag ccatgaacat g 91
6
75
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene.
6
atgaccatga ttacgaattc gagctggcgc gcggcgtaca agaacaattc gagtgaagcc 60
atgaacatgt accat 75
7
48
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the plc gene.
7
atgaccatga ttacgaattc gagcaattcg agtgaagcca tgaacatg 48
8
40
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene.
8
atgaccatga ttacgaattc gaggtgaagc catgaacatg 40
9
86
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene. hantoher
9
atgaccatga ttacgaattc caccgcgtgg cttgcaaccg ctggcgcgcg gcgtacaaga 60
acaattcgag tgaagccatg aacatg 86
10
30
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene.
10
atgaccatga ttacgaattc gaggtaccat 30
11
29
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a fusion of a DNA sequence originating from
pUC18 with another originating from Pseudomonas
corresponding to the pcl gene
11
atgacatgat tacgaattcg aggtaccat 29
12
10
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence is the peptide encoded by the DNA of SEQ ID NO 11.
12
Met Thr Met Ile Thr Asn Ser Ser Asp Ala
1 5 10
13
19
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is the same as the sequence at the ends of Tn5 transposon
13
acttgtgtat aagagtcag 19
14
8
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence is a consensus sequence corresponding to AMP binding site
14
Ser Ser Gly Thr Thr Gly Lys Pro
1 5
15
16
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence corresponds to the sequence of phenylacetyl-CoA-ligase
with a longer amino terminal end
15
Met Thr Met Ile Thr Asn Ser Ser Asn Ser Ser Glu Ala Met Asn Met
5 10 15
16
10
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence corresponds to the sequence of pheylacetyl-CoA-ligase
with a reduced amino terminal
16
Met Thr Met Ile Thr Asn Ser Arg Tyr His
5 10
17
10
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence corresponds to the sequence of pheylacetyl-CoA-ligase
with a reduced amino terminal
17
Met Thr Met Ile Thr Asn Ser Ser Asp Ala
5 10
18
25
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence comprises the amino terminal of the protein encoded by
SEQ ID NO6.
18
Met Thr Met Ile Thr Asn Ser Ser Trp Arg Ala Ala Tyr Lys Asn Asn
5 10 15
Ser Ser Glu Ala Met Asn Met Tyr His
20 25
19
7
PRT
Artificial Sequence
Description of Artificial Sequence The
sequence comprises the internal amino acid sequence of SEQ ID
NO18
19
Trp Arg Ala Ala Tyr Lys Asn
5
20
17
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a primer for amplifying phenylacetyl-CoA-ligase gene
20
atctgggtcg ggaacac 17
21
16
DNA
Artificial Sequence
Description of Artificial Sequence The
sequence is a primer for amplifying pheylonetyl-CoA-ligase gene
21
ggcgcaaggg tgacaa 16 | An isolated DNA encoding phenyl acetyl-CoA-ligase and a process of increasing the production of penicillin G in a strain of Penicillium chrysogenum by transforming the strain with the isolated DNA. Also vectors and host organisms having the isolated DNA. | 2 |
SUMMARY OF THE INVENTION
A portable milling unit having self contained means for actuating a cutter head, and simultaneously moving the head on a rectangular frame to machine the surface of the work, the cutterhead moving horizontally and vertically, selectively, to accomplish the cut.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a tube stack of a filter unit, showing the device attached to a door facing.
FIG. 2 is a side elevational view of a tube stack taken on the line 2--2 of FIG. 1.
FIG. 3 is a front elevational view taken on the line 3--3 of FIG. 1.
FIG. 4 is an enlarged side elevational view of the cutter head assembly, taken on the line 4--4 of FIG. 3, and
FIG. 5 is a cross sectional view taken on the line 5--5 of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawings, the numeral 1 designates a tube stack having a series of tubes 2, 2 mounted therein and on which a series of door facings are provided, as 3, 3 on which doors are to be mounted, such as 4, 4, as by bolts mounted in the bolt holes 5, 5.
The door facing 3 must be milled to provide a close fit of the doors 4 thereon. The cutter 6 is mounted on the transverse carrier 7, which is mounted on the transverse tracks 9, and which may be moved longitudinally of the framework 15. An externally threaded shaft 10, mounted in the longitudinal carriages 11, 11, extends through a threaded port 12 in the transverse carriage 7, and the motor 13, through the gear box 14, rotates the shaft 10 to move the carriage 7 transversely of the framework 15.
The longitudinal carriages 11, 11 have the wheels 16, 16 which are mounted in the tracks 17, 17 of the longitudinal members 19, 19 of the framework. Externally threaded shafts, 18, 18, are mounted in the longitudinal side members of the framework and extend through the internally threaded ports 20, 20 in the longitudinal carriages 11, 11. A motor 21 operates the gear box 22 to rotate the flanged pulleys 23, 23, which in turn rotate the flanged pullies 24, 24, through the belts 25, 25, and thus rotate the shafts 18, 18, moving the longitudinal carriages 11, 11 longitudinally on the framework, the motor 21 being reversible to provide movement in either direction. Similarly, flanged pullies 26, 26 are connected by the belt 27, to maintain an even torque on the shafts 18, 18.
The cutter consists of the support member 7, which is slotted at 8, providing track receiving means to receive the track 9. The hydraulic motor 31 rotates the drive shaft 32 on which the cutter head 33 is mounted. An externally threaded housing 34, having a longitudinal keyway 35, receives the motor 31, and a bearing 36, mounted in the bearing chamber 38 of the housing 34, is provided to support the shaft 32, and is maintained in position by means of the annular collar 37, the bearing chamber 38 being internally threaded at its outer end to receive the collar 37, and an internal flange 39 forming the end wall of the bearing chamber 38. A knurled adjusting nut 40 is internally threaded and mounted on the external threads of the housing 34, and has the annular indentation 8 to receive the collar 29, which is bolted to the flanged collar 30. The key 41, anchored to the collar 30, slides longitudinally in the slot 38.
In operation, the framework 15 is bolted to the door facing, using the bolt holes 5, 5, exposing the portion of the door facing, or the like, to be milled, and the cutter head is adjusted to bear against the surface to be milled by rotating the nut 40, causing the housing 34 to move longitudinally in the collar 30, the key 41 holding the collar 30 against rotation. The motor 31 is then actuated to rotate the cutter head 33, and the motor 13 is actuated to rotate the shaft 10, moving the carriage 7 transversely on the framework. When the transverse cut is completed, the carriage 7 is moved to one extreme position adjacent one end of the transverse track 9, and the motor 21 is actuated to rotate the shafts 18, 18 moving the carriages 11, 11 longitudinally, while the cutter continues to rotate, so that the cutter may be moved over the entire facing of the work, effecting a milling on the longitudinal and transverse facings.
Where the framework 15 is mounted on a work piece having three doors, the cutter head is moved longitudinally and transversely as required to mill all of the facings. The size of the work piece to be milled being limited only by the inside dimensions of the framework. | A unit for milling rectangular work members, where a machined fit is required, such as the door facings of a filter unit having a series of doors into an exchange unit, or equipment bases where a pump or turbine is being installed which requires a machined surface and it is necessary to accomplish the cut in place. | 1 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a system for controlling fuel injection in an internal combustion engine that has a cylinder injector for directly injecting fuel into a combustion chamber defined inside a cylinder, and a port injector for injecting fuel into an air-intake passage.
[0002] Conventionally, fuel injection into the intake passage, such as an intake port (hereinafter referred to as “port injection”), has been widely used for supplying fuel into the combustion chamber. In the port injection, the fuel is injected into a passage upstream of the intake valve that is disposed at the entrance of the cylinder. The fuel injected in this manner is introduced into the combustion chamber during the suction stroke of the cylinder in a mixed state substantially uniformly with the air.
[0003] On the other hand as an alternative injection method, direct injection of the fuel into the cylinder (hereinafter referred to as “cylinder injection”) has recently been suggested. In the cylinder injection, the fuel injection pressure is set comparatively higher than that in the case of using port injection to inject the fuel in an atomized state. The atomized fuel can be easily vaporized. In the cylinder injection, the temperature within the combustion chamber can be reduced by the vaporization heat as the vaporization of the atomized fuel occurs. Because the temperature inside the cylinder is reduced, the suction efficiency is improved and results in the increase in engine output.
[0004] In the cylinder injection method, deposits due to soot or particulate matter after fuel combustion can be accumulated in the vicinity of the fuel injection orifice because the tip of the injector is exposed within the combustion chamber. The accumulation of the deposits can decrease the amount of fuel injected and can change the injection conditions after time so that the combustion state can be deteriorated.
[0005] Accordingly, as described in Japanese Patent Laid-Open Application 63-138120, the injection method can be compulsorily transferred from the cylinder injection to the port injection after a predetermined period though the engine is in operation under conditions that enable cylinder injection. By forcibly switching the combustion injection method in this way, the temperature at the tip of the cylinder injector is increased to enable periodical burning of the accumulated deposits to reduce the accumulation.
[0006] However, the periodic transfer between the injection methods cannot perform appropriate transfer between the injection methods responsive to the amount of the accumulated deposits because the changeover can take place even when the deposits have not yet actually accumulated. Further, because the cylinder injection is discontinued when totally switching the injection method to the port injection, the advantageous effect of cylinder injection, such as improved suction efficiency due to reduced chamber temperature, cannot be obtained.
[0007] In addition, the disadvantages such as decrease in the fuel injection amount and the change in the form of atomized vapor are not always caused by deposit accumulation. Rather, such disadvantageous effects can also be caused by other factors, for example the decrease in the fuel injection pressure by some malfunction of the injector.
BRIEF SUMMARY OF THE INVENTION
[0008] In order to solve the problems described above, an object of the invention is to suppress deterioration in the combustion states by adjusting an appropriate fuel injection method to comply with the combustion state even when the circumstances would not permit normal fuel injection from cylinder injector due to causes such as deposit accumulation, as well as ensuring the effect of suction efficiency improvement by cylinder injection to a maximum extent.
[0009] In order to achieve the above objective, the present invention provides a system for controlling fuel injection in a combustion engine. The combustion engine has a cylinder and an intake passage connected to the cylinder. A first injector injects fuel into the cylinder. A second injector injects fuel into the intake passage. The fuel injection by the first injector and the second injector is controlled based on a respectively predetermined injection ratio. The system comprises a sensor for sensing an actual amount of fuel injected from said first injector. The system further comprises a controller for determining a deviation of the actual injection amount from a predetermined target injection amount, correcting at least one of said injection ratios based on the deviation, and actuating said second injector to perform fuel injection together with the first injector.
[0010] In one aspect, the injection ratio of the intake passage injector is increased based on the detection that the amount of fuel injected is liable to be lower than the target injection amount.
[0011] In this structure, the difference between the target injection amount and the amount of fuel actually injected from the cylinder injector 17 is detected. The injection ratios of the cylinder injector 17 and the port injector 18 are adjusted based on the detected deviation so that the fuel injection from the port injector 18 is performed in addition to the fuel injection from the cylinder injector 17 while the operation state of the internal combustion engine is suitable for fuel injection from the cylinder injector 17 . Accordingly, even in the case where the amount actually injected from the cylinder injector can be lower than the target injection amount, for example due to deposit accumulation at the cylinder injector 17 , the fuel injection methods can be appropriately adjusted to comply with the circumstances. Accordingly, the deterioration in the combustion states can be suppressed while the effect of increased suction efficiency due to cylinder injection can be retained at a maximum extent.
[0012] In particular, the above-described system can compensate the fuel injection by the port injector 18 by increasing the injection ratio of the port injector 18 based on the detection that the actual amount injected from the cylinder injector 17 is liable to be lower than the target amount even in the case where the flow rate is reduced by causes such as deposit accumulation.
[0013] Alternatively, by adopting an arrangement to decrease the injection ratio of the port injector 18 based on the detection that the actually injected amount from the cylinder injector 17 is liable to be higher than the target injection amount, the fuel injection from the cylinder injector 17 can be increased responsive to conditions such as elimination of deposits, so that the advantageous effect of increased suction efficiency due to cylinder injection can be ensured.
[0014] Note that the phrase “while said engine operates in a condition in which said engine permits fuel injection from said cylinder injector,” includes both the circumstances where the fuel injection is performed, only by either the cylinder injector 17 and by the port injector 18 in addition to the cylinder injector 17 .
[0015] In another aspect of the above-described system according to the invention, the deviation is determined based on a correction value obtained from air fuel ratio control of the cylinder injector and the injection ratios are established based on the correction value.
[0016] In the period where the fuel injection is performed only by the cylinder injector 17 , the target injection amount of the cylinder injector 17 is identical to the basic injection amount established in accordance with the engine operation state. If the actually injected amount from the cylinder injector 17 is different from the basic injection amount during this period, a feedback correction value is set through the air fuel ratio control to eliminate the difference. Further, also in the periods where the port injector 18 is used in addition to the cylinder injector 17 , the difference between the actual injection amount and the target amount is similarly reflected in the feedback correction value. Accordingly, the feedback correction value is a value which reflects the tendency between the actual injection amount and the basic injection amount of the injectors 17 and 18 to differ.
[0017] In the above-described structure, the injection ratios can be established to be conformal to the circumstances that take place in the cylinder injector, such as the deposit accumulation, because the injection ratio of each injector can be set based on the feedback correction value.
[0018] The correction value in the air fuel ratio control can be also changed due to other circumstances than in the case where the cylinder injector 17 is no longer capable of fulfilling its original function due to for example deposit accumulation, and the correction value can change, for example by rapid change in the engine operation states. Here, while the change in the correction value due to the rapid change in the engine operation state is of a temporary nature, the change in the correction value due to deposit accumulation is comparatively slack and has a stationary tendency.
[0019] Accordingly, in a further aspect of the invention, the correction value is a learning value which is learnt responsive to the tendency which is constantly observed in the deviation of the target injection amount from the actual amount of fuel injected. In this structure, the injection ratios can be appropriately corrected in accordance with the correction value, while avoiding the effect of temporary disturbance such as rapid change in the engine operation.
[0020] In a still further aspect, the injection ratios can be variably established responsive to the amount of the correction value when the controller corrects the injection ratios based on the correction value.
[0021] In this structure, the injection ratios can further appropriately be corrected responsive to the degradation of the functions when the cylinder injector 17 is in a state where it is no longer fulfilling its original functions, for example, due to deposit accumulation.
[0022] Further, when the injection ratios are established responsive to the correction value as described above, the controller can reset the learning value when the learning value diverges from a predetermined range and reflects said learning value for adjustment of said injection ratios. Note that the “predetermined range” is preferably set at a level that enables determination that the fuel injection function of the cylinder injector 17 has been changed to an extent that it cannot be ignored due to, for example, deposit accumulation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:
[0024] FIG. 1 is a block diagram which schematically shows a fuel injection control system in an embodiment in accordance with the invention;
[0025] FIG. 2 is a flow chart schematically showing the fuel amount control according to the foregoing embodiment;
[0026] FIG. 3 is a timing chart showing the relationship between the deposit accumulation conditions and the fuel amount control; and
[0027] FIG. 4 is a schematic side elevational view of an injector orifice showing the change in conditions of injection due to deposit accumulation on the cylinder injector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] An embodiment of the invention is described below by referring to FIGS. 1 to 4 .
[0029] FIG. 1 schematically shows a system for controlling fuel injection of the engine in an embodiment according to the invention. A piston 13 is disposed within the cylinder 12 of the engine 11 . The intake passage 15 and an exhaust passage 16 are respectively connected to the combustion chamber 10 defined by the piston 13 .
[0030] The intake passage injector 18 is provided on the intake passage 15 for injecting fuel into the intake passage 15 . The cylinder injector 17 is provided on the cylinder 12 in a manner in which the tip of the injector is exposed within the combustion chamber 10 so that fuel can be directly injected from the orifice (not shown in the figures) of the cylinder injector 17 into the combustion chamber 10 . The fuel thus injected from the intake passage injector 18 or the cylinder injector 17 are mixed with the suction air introduced into the combustion chamber 10 through the intake passage 15 . The mixed air is burned in the combustion chamber 10 by operation of the ignition plug 14 and is then exhausted through the exhaust passage 16 from the combustion chamber 10 .
[0031] An air flow meter 22 is disposed in the intake passage 15 for detecting the amount of suction air. An oxygen sensor 23 is disposed in the exhaust passage 16 for detecting the oxygen concentration of the exhaust. In addition, a rotational speed sensor 24 for detecting the rotational speed of the engine 11 is provided in the vicinity of the crankshaft (not shown in the figures). The signals detected by the sensors 22 to 24 are inputted to the controller 21 of the engine 11 . The controller 21 then calculates the amount of suction air introduced into the combustion chamber 10 per stroke, fuel injection, and air/fuel ratio, etc., based on the detected signals. The controller 21 then sets the fuel injection method based on the engine operation states such as rotational speed and engine load (amount of suction air or fuel injection). More particularly, the fuel injection method is adjusted to any one of, fuel injection by port injector 18 alone, fuel injection by cylinder injector 17 alone and fuel injection by both of the injectors 17 and 18 . In particular, the fuel injection method is set so that the fuel is injected at least from the cylinder injector 17 in order to obtain suction efficiency improvement from the fuel injection, while the engine is operating at a high load.
[0032] Further, the controller 21 calculates a basic injection amount based on the operation state of the engine 11 so that the air fuel ratio reaches a target air fuel ratio (theoretical air fuel ratio in general), and further corrects the basic injection according to the oxygen concentration in the exhaust gas to perform so-called air fuel ratio control. The steps for performing the air fuel ratio control is described below.
[0033] In the air fuel control, the basic injection amount QB is calculated on the assumption that the air fuel ratio is a theoretically calculated ratio based on the state of engine operation such as the engine load (for example the amount of suction air) and engine rotational speed. Because the fuel injection system is affected by various disturbances, fuel injection cannot be performed in some cases in a manner complying with the actual engine operation state depending upon the thus calculated basic injection amount QB. For example, while the engine is in a transient operation such as during acceleration and deceleration of the engine 11 in which the suction air amount drastically changes, the actual air fuel ratio may not correspond to the theoretical air fuel ratio though the fuel injection is performed based on the calculation of the basic injection amount QB that has been obtained from the already detected suction air amount. The same can be said in the case where the fuel injection cannot be performed properly because of the accumulation of the deposits on the tip of the injector, specifically the injector orifice (not shown in the figures) of the cylinder injector 17 (see FIG. 4 ) and in the case where the injection pressure has decreased by malfunction of the fuel pressure feeding system of the cylinder injector 17 .
[0034] Accordingly, the air fuel ratio control in general performs feedback control to compensate for the influence from the disturbances. That is, the control unit 21 calculates a correction coefficient, FAF, (initial value “1.0”) based on the deviation between the theoretical air fuel ratio and the actual air fuel ratio. Here, the actual air fuel ratio is calculated based upon detection of the oxygen sensor 23 . The fuel injection amount is thereby corrected to minimize the deviation by multiplying the correction coefficient FAF by the basic injection amount QB.
[0035] Specifically, in the case where the oxygen concentration in the exhaust gas is lower than the reference value that corresponds with the theoretical air fuel ratio, in other words, in the case of a so-called “rich” state, the correction coefficient FAF is set at a smaller value than the initial value 1.0 in order to decrease the fuel injection. On the other hand, in the case where the oxygen concentration is high, namely in the case of a so-called “lean” state, the correction efficient FAF is set at a greater value than 1.0 in order to increase the fuel injection.
[0036] The feedback control further calculates a learning value, KG, in order to learn or determine the tendency of the correction coefficient FAF to remain stationary or constant and to reflect the result of learning in the correction of the fuel injection. The learning value KG is a correction coefficient for correcting the basic injection amount QB that has been corrected by the correction coefficient FAF in an operation of [QB·FAF·(1+KG)] whose initial value is “0,” and is indicative of the stationary differentiating tendency between the actual injection amount and the basic injection amount QB.
[0037] Specifically, an average FAFAVE is calculated for the correction coefficient FAF in a certain period. When the average FAFAVE exceeds a predetermined lean reference value (>1.0), a predetermined amount α is added to the leaning value KG and at the same time the value α is subtracted from the correction coefficient FAF. When the average FAFAVE lowers a predetermined rich reference value (<1.0), the predetermined value α is subtracted from the leaning value KG and at the same time the value α is added to the correction coefficient FAF. Note that in the case where the actual air fuel ratio substantially matches the theoretical air fuel ratio so that the average FAFAVE of the correction coefficient FAF is in between the rich and lean reference values, the learning value KG is set to maintain the learning value KG at that moment.
[0038] Here if the actual injection amount of the injectors 17 and 18 have a stationary tendency to be lower than the basic injection amount QB, for example due to the deposit accumulation at the cylinder injector 17 , the learning value KG will be a greater value than the initial value of zero by an amount complying with the tendency for the decrease. Alternatively, when the accumulated deposits on the cylinder injector 17 are burnt down to thereby enable normal fuel injection by the cylinder injector 17 , the above described learning value KG is gradually decreased. Accordingly, the degree of deposit accumulation on the cylinder injector 17 can be monitored based upon the learning value KG.
[0039] The control system variably sets the injection ratio of the injectors 17 and 18 responsive to the degree of deposit accumulation so that the fuel injection is performed by the port injector 18 together with the fuel injection by the cylinder injector 17 when the engine operation is in a state where fuel injection is performed, at least by the cylinder injector 17 . The fuel injection control is described in more detail below.
[0040] FIG. 2 shows a flowchart which depicts the steps for the fuel injection control. The controller 21 repeatedly performs the series of the steps shown in the flowchart after a predetermined control periods. Note that the case of starting the series of steps from the state where the engine operation is in a state where the fuel injection is being performed only by the cylinder injector 17 .
[0041] In step S 101 , the controller 21 calculates the correction coefficient FAF in order to feedback the actual injection of the cylinder injector 17 so that the air fuel ratio is a theoretical value. The learning value KG is then calculated based upon the average FAFAVE of the correction efficient FAF.
[0042] Next in step S 102 , the controller 21 compares the reference values KGINC and KGDEC with the learning value KG to determine whether the conditions 1 and 2 shown below are fulfilled.
Condition 1 KG > KGINC Condition 2 KG < KGDEC
[0043] Here, the reference value KGINC is a reference value for determining whether the influence by the deposits accumulated on the cylinder injector 17 orifice is not negligible (condition 1). The reference value KGDEC is a reference value for determining whether the deposits accumulated on the cylinder injector 17 orifice has been burnt down and the influence of the deposits on the fuel injection is now negligible (condition 2). Accordingly, the degree of difference between the actual injection amount of the cylinder injector 17 and the target amount is detected through the steps S 101 and S 102 .
[0044] In step S 102 , the controller 21 discontinues the steps when neither of the conditions 1 and 2 are fulfilled.
[0045] On the other hand when one of the conditions 1 and 2 is fulfilled, in other words, either in the state that the cylinder injector orifice is subjected to the influence of a negligible amount of the accumulated deposits, or that the deposits have been burnt down so that the influence of the deposits on the fuel injection is negligible, the controller 21 proceeds to the step S 103 .
[0046] In the subsequent steps S 103 and S 104 , the injection ratio KPINJ is updated through the operations (1) and (2) shown below.
KPINJ←KPINJ+KG (1)
KG←0 (2)
[0047] The injection ratio KPINJ of equation (1) indicates the ratio of the fuel injected by the port injector 18 out of the basic injection amount QB. The initial value is set at zero.
[0048] In the steps S 103 and S 104 , the learning value KG is a positive value when the deposits accumulate on the cylinder injector orifice sufficiently to create a tendency to lower the amount of fuel injected from the cylinder injector 17 , compared to the normal state. Accordingly, the injection ratio KPINJ is set greater by the learning value KG at that moment in accordance with the operations (1) and (2), to increase the amount of fuel injected from the port injector 18 and to decrease the fuel injected from the cylinder injector 17 .
[0049] On the other hand, when the deposits on the cylinder injector orifice is burnt down to transit the state of the cylinder injector 17 to enable normal injection, the learning value KG will be a negative value. Accordingly, the injection ratio KPINJ is decreased by the operations (1) and (2). Thereby, the amount of fuel injected from the port injector 18 is decreased, as well as the amount of fuel injected from the cylinder injector 17 is increased.
[0050] After thus calculating the injection ratio KPINJ and the learning value KG, the controller 21 then calculates the fuel injection amount Q 1 of the cylinder injector 17 and the amount Q 2 of the cylinder injector 18 based on the operations (3) and (4) shown below in steps S 105 and S 106 .
Q 1 ←QB·FAF·(1+KG) (3)
Q 2 ←QB·KPINJ (4)
[0051] After calculating the fuel injection amount Q 1 and Q 2 for the injectors 17 and 18 to correspond to the state of deposit accumulation on the cylinder injector orifice as described above, the controller 21 discontinues the series of steps. Note that the steps starting from the state in which only the cylinder injector 17 is used in the above, it is also possible to detect the difference between the actual injection and the target injection amount of the cylinder injector 17 also when the port injector 18 is used for fuel injection as well as the cylinder injector 17 , similarly through the steps S 101 and S 102 .
[0052] An embodiment for fuel injection control in accordance with the invention is next described by referring to the timing chart shown in FIG. 3 . In the timing chart, a case in which the deposits are gradually accumulated at the orifice of the cylinder injector 17 and the deposits are then burnt down after a certain period is exemplified.
[0053] In the initial period between the timings t 1 and t 2 , the fuel injection is performed only by the cylinder injector 17 . In this time frame, the deposits are gradually accumulated on the orifice of the cylinder injector 17 and the actual fuel injection decreases by the effect of the deposits. In order to compensate for the effect, the learning value KG increases.
[0054] At the timing t 2 , since neither of the conditions 1 and 2 (step S 102 ) is fulfilled, the injection ratio KPINJ is maintained at the initial value zero. Accordingly, the fuel injection state at this moment is performed continuously in the state in which only the cylinder injector 17 is used. Note however that the learning value KG gradually increases as the amount of deposit accumulation increases.
[0055] When condition 1 is fulfilled at the timing 3 (step S 102 : condition 1 is fulfilled), the injection ratio KPINJ from the port injector 18 increases by the learning value KG 1 from its initial value zero, to be set at “KPINJ 1 .” As a result, the fuel injection by the port injector 18 is started. On the other hand, the amount of the injection from the cylinder injector 17 is decreased by the amount injected from the port injector 18 .
[0056] At timing t 4 , neither of the conditions 1 and 2 (step S 102 ) is fulfilled. Accordingly, there is no change in the fuel injection amount injected by the port injector 18 in the period between timings t 3 and t 5 . On the other hand, the amount of fuel injected by the cylinder injector 17 increases due to the increase in the learning value KG.
[0057] At timing t 5 the learning value KG 2 exceeds KGINC to fulfill the condition 1 of step S 102 . Accordingly, the injection ratio of the port injector 18 is increased by the learning value KG 2 at this moment. On the other hand, the fuel injection ratio from the cylinder injector 17 decreases by the learning value KG 2 .
[0058] At timing t 6 , neither of the conditions 1 and 2 (step S 102 ) is fulfilled. Therefore the injection ratio of the port injector 18 is not changed from KPINJ 2 . Similarly, since there is no change to the amount of deposit accumulation between the timings t 6 and t 7 and the learning value KG stays constant, the injection amount from the cylinder injector 17 is not changed.
[0059] When the deposits disappear by some cause, such as being burnt or dropped, for example the decrease in the amount of the deposit accumulation takes place as that shown in the period between timings t 7 and t 8 , the fuel injection from the cylinder injector 17 increases. Accordingly, in order to decrease the fuel injection of the cylinder injector 17 to the reference value, the learning value KG decreases. The learning value KG 3 at the timing t 8 is lower than the reference value KGDEC so that the condition 2 is fulfilled. Accordingly at the timing t 8 , the learning value KG 3 is added to the injection ratio KPINJ from the port injector 18 . Since the learning value KG 3 is a negative value, the fuel injection from the port injector 18 decreases. On the other hand, the injection ratio of the cylinder injector increases as the ratio is reduced by the learning value KG 3 .
[0060] When the deposit accumulation continues to decrease, the learning value KG 4 at the timing t 9 after the deposits are completely removed is also lower than the reference value KGDEC. Accordingly, the injection ratio of the port injector 18 is further decreased by KG 4 . As a result, KPINJ is lowered to zero and the injection method is altered to a manner in which only the cylinder injector 17 injects the entire amount of the fuel without using the port injector 18 .
[0061] As described above the present invention performs the alteration of the fuel injection methods by using the learning value KG which depicts the combustion states at that moment. Since the fuel control of the present invention appropriately transfers the fuel injection method responsive to the engine operation and the conditions of the injectors 17 and 18 , the advantageous effect of reducing temperature of the cylinder through the use of cylinder injector 17 and resultant increase in the suction amount can be obtained in accordance with the conditions while avoiding the disadvantages of the deposit accumulation by the use of the cylinder injector 17 .
[0062] Further, the feedback alters the fuel injection ratio KPINJ between the cylinder injector 17 and the port injector 18 by using the learning value KG. By doing so, not only unnecessary switching between the cylinder injector 17 and the port injector 18 can be prevented, but also the fuel injection ratio KPINJ can be altered responsive to the absolute value of the learning value KG, rapidly when it is necessary to catch up with the rapid change of the circumstances and gradually when it is necessary to gradually change the injection method. Accordingly, the fuel injection ratios of the injectors 17 and 18 can be suitably adjusted to a state in a faster manner than the case of changing the ratio by a constant value.
[0063] It should be apparent to those skilled in the art that the present invention may be embodied in many other specific forms without departing from the spirit or scope of the invention. Particularly, it should be understood that the invention may be embodied in the following forms.
[0064] While the learning value KG was used as a parameter for monitoring the deposit accumulation, the correction coefficient FAF alone can be used or both of the feedback correction values FAF and KG can be used. The advantageous effects of the invention can be obtained provided that the fuel injection amount from each of the injectors 17 and 18 can be changed to comply with the circumstances by using the feedback correction value.
[0065] While there are KGINC and KGDEC for the reference value for comparison with the learning value KG in step S 102 , the absolute value of the KGINC and KGDEC can be the same or different.
[0066] In the step S 103 of altering the fuel injection ratio KPINJ from the port injector 18 , the learning value KG is added to the fuel injection ratio KPINJ. However, it is also possible to add only a portion of the learning value KG to the fuel injection ratio KPINJ, for example through an operation of multiplying a coefficient by the learning value KG.
[0067] The method of setting the learning value to zero after altering the fuel injection ratio KPINJ is described in step S 104 . While the absolute value of the learning value needs to be decreased after alteration of the injection ratio KPINJ, it need not necessarily be decreased to zero in alternate embodiments.
[0068] Therefore, the present examples and embodiments are to be considered as illustrative and not restrictive and the invention is not to be limited to the details given herein, but may be modified within the scope and equivalence of the appended claims. | A system for controlling fuel injection in an engine. The engine includes an intake passage, an intake passage injector, a cylinder having a combustion chamber, and a cylinder injector for injecting a target amount of fuel into the combustion chamber. The system includes a controller for controlling the intake passage and cylinder injectors to permit fuel injection, each with an injection ratio, while said engine operates in a condition in which said engine permits fuel injection from said cylinder injector, a sensor for sensing the amount of fuel injected from the cylinder injector, a detector for detecting the difference between the target injection amount and the amount of fuel injected and an adjustor for adjusting the injection ratio based on the result of the detection by the detector so that the intake passage injector performs fuel injection together with the fuel injection performed by the cylinder injector. | 5 |
Cross-Reference to Related Applications
[0001] This application claims the benefit of U.S. provisional patent application Ser. No. 62/346,182, filed Jun. 6, 2016, which is hereby incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] Although minor earthquakes are common, with thousands of smaller earthquakes occurring daily, larger magnitude seismic events can cause personal injury, death and property and environmental damage, particularly in heavily populated areas.
[0003] Two approaches have been traditionally utilized to prevent or limit damage or injury to objects or payloads due to seismic events. In the first approach, used particularly with structures themselves, the objects or payload articles are made strong enough to withstand the largest anticipated earthquake. However, in addition to the relative unpredictability of damage caused by tremors of high magnitude and long duration and of the directionality of shaking, use of this method alone can be quite expensive and is not necessarily suitable for payloads to be housed within a structure. Particularly for delicate, sensitive or easily damaged payload, this approach alone is not especially useful.
[0004] In the second approach, the objects are isolated from the vibration such that the objects fail to experience the full force and acceleration of the seismic shock waves. Various methods have been proposed for accomplishing isolation or energy dissipation of a structure or object from seismic tremors, and these methods may depend in some measure on the nature of the object to be isolated.
[0005] Thus, buildings and other structures may be isolated using, for example, passive systems, active systems, or hybrid systems. Such systems may include the use of one or more of a torsional beam device, a lead extrusion device, a flexural beam device, a flexural plate device, and a lead-rubber device; these generally involves the use of specialized connectors that deform and yield during an earthquake. The deformation is focused in specialized devices and damage to other parts of the structure are minimized; however the deformed devices often must be repaired or replaced after the seismic event, and are therefore largely suitable for only one use.
[0006] Active control systems requite an energy source and computerized control actuators to operate braces or dampers located throughout the structure to be protected. Such active systems are complex, and require service or routine maintenance.
[0007] For objects other than buildings, bridges and other structures, isolation platforms or flooring systems may be preferable to such active or deformable devices. Thus, for protection of delicate or sensitive equipment such as manufacturing or processing equipment, laboratory equipment, computer servers and other hardware, optical equipment and the like an isolation system may provide a simpler, effective, and less maintenance-intensive alternative. Isolation systems are designed to decouple the objects to be protected (hereinafter the “payload”) from damage due to the seismic ground motion.
[0008] Isolators have a variety of designs. Thus, such systems have generally comprised a combination of some or all of the following features: a sliding plate, a support frame slidably mounted on the plate with low friction elements interposed therebetween, a plurality of springs and/or axial guides disposed horizontally between the support frame and the plate, a floor mounted on the support frame through vertically disposed springs, a number of dampers disposed vertically between the support frame and the floor, and/or a latch means to secure the vertical springs during normal use.
[0009] Certain disadvantages to such pre-existing systems include the fact that it is difficult to establish the minimum acceleration at which the latch means is released; it is difficult to reset the latch means after the floor has been released; it may be difficult to restore the floor to its original position after it has moved in the horizontal direction; the dissipative or damping force must be recalibrated to each load; there is a danger of rocking on the vertical springs; and since the transverse rigidity of the vertical springs cannot be ignored with regard to the horizontal springs, the establishment of the horizontal springs and an estimate of their effectiveness, are made difficult. Ishida et al., U.S. Pat. No. 4,371,143 have proposed a sliding-type isolation floor that comprises length adjustment means for presetting the minimum acceleration required to initiate the isolation effects of the flooring in part by adjusting the length of the springs.
[0010] Yamada et al., U.S. Pat. No. 4,917,211 discloses a sliding type seismic isolator comprising a friction device having an upper friction plate and a lower friction plate, the friction plates having a characteristic of Coulomb friction, and horizontally placed springs which reduce a relative displacement and a residual displacement to under a desired value. The upper friction plate comprises a material impregnated with oil, while a lower friction plate comprises a hard chromium or nickel plate.
[0011] Stahl (U.S. Pat. No. 4,801,122) discloses a seismic isolator for protecting e.g., art objects, instruments, cases or projecting housing comprising a base plate connected to a floor and a frame. A moving pivoted lever is connected to a spring in the frame and to the base plate. The object is placed on top of the frame. Movement of the foundation and base plate relative to the frame and object causes compression of the lever and extension of the spring, which then exerts a restoring force through a cable anchored to the base plate; initial resistance to inertia is caused due to friction between the base plate and the frame.
[0012] Kondo et al., U.S. Pat. No. 4,662,133 describes a floor system for seismic isolation of objects placed thereupon comprising a floor disposed above a foundation, a plurality of support members for supporting the floor in a manner that permits the movement of the floor relative to the foundation in a horizontal direction, and a number of restoring devices comprising springs disposed between the foundation and the floor member. The restoring members comprise two pair of slidable members, each pair of slidable members being movable towards and away from each other wherein each pair of slidable members is disposed at right angles from each other in the horizontal plane. Stiles et al., U.S. Pat. No. 6,324,795 disclose a seismic isolation system between a floor and a foundation comprising a plurality of ball and socket joints disposed between a floor and a plurality of foundation pads or piers. In this isolation device, the bearing comprises a movable joint attached to a hardened elastomeric material (or a spring); the elastic material is attached on an upper surface of the ball and socket joint and thus sandwiched between the floor and the ball and socket joint; the bearing thus tilts in relation to the floor in response to vertical movement. The floor is therefore able to adjust to buckling pressure due to distortion of the ground beneath the foundation piers. However, the device disclosed is not designed to move horizontally in an acceleration-resisting manner.
[0013] Fujimoto, U.S. Pat. No. 5,816,559 discloses a seismic isolation device quite similar to that of Kondo, as well as various other devices including one in which a rolling ball is disposed within the tip of a strut projecting downward from the floor in a manner similar to that of a ball point pen.
[0014] Bakker, U.S. Pat. No. 2,014,643, is drawn to a balance block for buildings comprising opposed inner concave surfaces with a bearing ball positioned between the surfaces to support the weight of a building superstructure.
[0015] Kemeny, U.S. Pat. No. 5,599,106 discloses ball-in-cone bearings.
[0016] Kemeny, U.S. Pat. Nos. 7,784,225 and 8,104,236 discloses seismic isolation platforms containing rolling ball isolation bearings.
[0017] Hubbard and Moreno, U.S. Pat. Nos. 8,156,696 and 8,511,004 discloses apparatus and methods involving raised access flooring structure for isolation of a payload placed thereupon.
[0018] Moreno and Hubbard, U.S. Pat. No. 8,342,752 disclose isolation bearing restraint devices. Isolation bearings are disclosed in Hubbard and Moreno, U.S. Patent Publication US 2013/0119224 filed on Sep. 25, 2012.
[0019] Moreno and Hubbard, U.S. Patent Publication No. U.S. 2011/0222800 disclose methods and compositions for isolating a payload from vibration.
[0020] Hubbard and Moreno, U.S. Provisional Patent Applications No. 62/079,475, 62/262,816 and 62/335,203 describe seismic isolation of container transport and storage systems.
[0021] Chen, U.S. Pat. No. 5,791,096 discloses a raised floor system.
[0022] Denton, U.S. Pat. No. 3,606,704 discloses an elevated floor structure suitable for missile launching installations with vertically compressible spring units to accommodate vertical displacements of the subfloor.
[0023] Naka, U.S. Pat. No. 4,922,670 is drawn to a raised double flooring structure which is resistant to deformation under load. The floor employs columnar leg members that contain a pivot mounting near the floor surface, which permits to floor to disperse a load in response to a side load.
[0024] All patents, patent applications and other publications cited in this patent application are hereby individually incorporated by reference in their entirety as part of this disclosure, regardless whether any specific citation is expressly indicated as incorporated by reference or not.
SUMMARY OF THE INVENTION
[0025] The present invention is directed to new seismic isolation systems. The present systems are effective in providing one or more operational benefits, for example, relative to the past systems. Such benefits are advantageously achieved in a straightforward manner, for example, without major structural changes to the past isolation systems.
[0026] The present invention may be involved, or used in conjunction with a wide variety of “rolling member”-type seismic isolation bearings.
[0027] Although not exclusively, in some examples the invention may involve, or may be used in conjunction with, a “low rise” platform or flooring system such as that disclosed in International Patent Application No. PCT/US2013/028621, filed on Mar. 1, 2013.
[0028] In some examples, the invention may involve, or be used in conjunction with a raised isolation flooring system such as, without limitation, systems such as the ones disclosed by U.S. Pat. Nos. 8,156,696 and 8,511,004. In other examples the invention may involve, or be used in conjunction with, seismic isolation platforms such as, without limitation, those disclosed in U.S. Pat. Nos. 7,784,225 and 8,104,236.
[0029] In other examples the invention may involve, or be used in conjunction with, isolation bearings such as, without limitation, those disclosed in U.S. Pat. No. 5,599,106.
[0030] Isolation bearings and systems such as, without limitation, those disclosed in e.g., U.S. Pat. Nos. 5,599,106; 7,784,225; 8,104,236; 8,156,696 and 8,511,004 provide seismic isolation through the utilization of isolation bearings comprising at least one (and usually two) horizontally extending bearing plate(s) each with an indented, generally concave (e.g., partly spherical conical) surface. A cross-sectional profile through a midline vertical axis of such a bearing plate shows that the generally concave surface comprises a shape, generally symmetrical around a central vertical axis. This shape may comprise a substantially conical shape, a substantially spherical shape, or a shape, comprising a linked combination of linear and radial shapes. When the generally concave surface of the bearing plate is a top surface of the bearing plate the bearing plate shall be considered “upward” facing, whereas when this surface is the bottom surface of the bearing plate, the concave surface shall be considered “downward” facing.
[0031] Generally at least one bearing plate supports, or is supported by a rolling member. By “rolling member” is meant one or more roller or bearing which is positioned between two, preferably identical, load-bearing surfaces of opposing bearing plates, and supports and isolates a payload from seismic vibration via a rolling movement permitting the opposing bearing plates to dislocate in approximately parallel plates with respect to each other during a seismic vibration. Examples of rolling members include, for example and without limitation, a sphere or rolling ball, such as a ball bearing, or one or more rolling rods, such as one or more roller. In preferred rolling ball isolation bearing systems a rolling ball is between opposing upward-facing and downward-facing isolation bearing plates in such a manner that when a seismic event occurs, horizontal ground movement of the floor or foundation is isolated from the payload supported by the isolation bearings. Horizontal ground movement of the lower bearing plate is attenuated by the inertia of the payload mass on the upper bearing plate so that the rolling member, located at rest in the center of the bearing plates, is free to move out of the center of the lower plate as the plate moves under it. The rolling member(s) may permit the upper plate to move in any direction (relative to the lower plate) opposite to the direction of lower plate movement due to seismic activity.
[0032] A major advantage to such a rolling member is that, since it is substantially equally free to move the same distance in any horizontal direction (i.e., along the x and y axes) given a constant force, the bearing does not require additional means to translate and isolate non-linear forces, or forces having both x and y components, as is necessary with isolation equipment using only one or more unidirectional rollers, springs, skids or the like as the primary means of isolating the payload. Additionally, because of the use of a generally concave, generally symmetrical bearing surface, the bearing is “self-initializing”, with the rolling member returning to the center of the bearing plate following a seismic tremor, thus restoring the rolling member to its initial resting position.
[0033] One disadvantage that has been noted with regard to the movement of the rolling member (e.g., ball, roller, etc.) relative to the bearing plate(s) is the tendency for the rolling member to skip, slide or skid relative to the plate or plates. This type of uneven movement or action between the rolling member and the plate or plates results (or can result) in the isolation system being slow to react (or even note reacting) in response to events (seismic events) in which a smooth, consistent response by the system is advantageous or even required.
[0034] The present invention is directed to methods and apparatus which involve improved seismic isolation bearings and systems utilizing such seismic isolation bearings, as well as methods of making and using such bearings and systems. In particular examples, the present invention involves seismic isolation systems utilizing one or more “rolling ball” or other “rolling member” (roller) isolation bearing comprising a bearing plate, for example, a bearing plate made of metal, i.e., a metallic bearing plate, for example, having a polygonal shape. That is, the isolation bearing comprises at least one payload-supporting “pan” or bearing plate assembly (plate plus optional frame) having a polygonal shape in a plan view comprising a load-bearing surface having a cross-sectional profile comprising a generally conical shape, a generally spherical shape, or a shape, generally symmetrical around a central vertical axis, comprising a linked combination of linear and radial shapes.
[0035] In one aspect, the present invention is directed to a seismic isolation bearing assembly comprising a first isolation bearing plate; a second isolation bearing plate; and a ball or other rolling member between the first and second isolation bearing plate, each of the first and second isolation plates comprises a hard material, advantageously a metal or metal alloy, and a surface facing the other isolation plate coated with, or otherwise comprising, a polymeric material different from the hard material.
[0036] The polymeric material may comprise an organic polymeric component, for example, a polymeric material effective to enhance the operability of the assembly relative to the assembly without the polymeric material. For example, the present assembly may provide at least one of (1) increased operational smoothness, (2) increased operational safety, (3) increased operation efficiency, (4) increased operational reliability, (3) increased ability to “grip” the rolling member, such as through adhesiveness, through a charge opposite that of the surface of the rolling member, hydrophilic/hydrophobic interactions, micro-mechanical means, or otherwise, and (5) reduced incidence of bearing assembly failure relative to a substantially identical bearing assembly without an isolation bearing assembly the polymeric material.
[0037] The polymeric material may comprise any suitable, e.g., effective, such material. The polymeric material advantageously is such that it can be effectively applied to the load bearing surfaces of the isolation plates and remain on such load bearing surfaces to reduce or even eliminate sliding, skipping and/or stopping of the rolling ball and other or roller bearing relative to the isolation barrier plates. The polymeric material on the facing surfaces of the isolation plates is effective to provide more consistent and responsive movement of the rolling member relative to the relative movement of the isolation barrier plates.
[0038] The amount of the polymeric material placed on the load bearing surfaces of the isolation barrier plates is sufficient to be effective in reducing or even eliminating such skipping and/or stopping of the ball bearing or roller bearing relative to the isolation barrier plates.
[0039] Such amount of the polymeric material, expressed in terms of thickness on the surface of the isolation barrier plates may range from about 0.01 or about 0.03 or about 0.05 inches to about 0.1 or about 0.15 or about 0.25 inches. The thickness of the polymeric material may vary depending on the specific application or polymer involved, the specific isolation bearing plates and rolling member(s) being used and the specific conditions to which the polymeric material is to be exposed.
[0040] The polymeric material may be any polymeric material which, when placed on the isolation plates is effective to reduce the sliding, skipping and/or stopping of the rolling member relative to the isolation plates.
[0041] The polymeric material may be placed on the surface of an isolation plate as a liquid, a liquid/solid slurry or other useful form. The polymer may also be formed on the surface of the isolation plates, for example, by providing a reactant, or a mixture of reactants on the surface of the isolation plates and allowing the polymer coating to form, for example, by evaporation of the liquid or chemical reaction of the reactants on the surface.
[0042] In other examples, the isolation plate surface may be fabricated with a polymeric surface, such as by molding (e.g., injection molding) or extrusion, such as by extrusion of a polymeric coating on the load-bearing surface of the isolation plate or other part.
[0043] The polymeric material chosen should be effective at the conditions of use of the isolation plates. For example, polymeric materials advantageously should not melt or decompose or otherwise become ineffective at conditions to which the isolation plates are exposed during use.
[0044] The polymeric material advantageously is useful on the isolation plates for at least about 5 years or about 10 years or for the useful life of the isolation plates.
[0045] The polymeric material may comprise hydrocarbon-containing polymers, non-hydrocarbon polymers, for example, silicone polymers, and/or mixtures of two or more polymers.
[0046] In short, any polymeric material or combination of polymeric materials which are useful and effective to prevent (or retard) sliding, skipping, skidding and/or stopping of rolling members relative to surfaces of isolation plates may be employed in accordance with the present invention.
[0047] In one example, the polymeric material employed provides a degree of stickiness or tackiness, for example, a slight degree of stickiness or tackiness, to the treated surfaces of the isolation plates. Such sticky or tacky isolation plate surfaces have a beneficial effect of at least assisting in reducing or preventing skipping, skidding and/or stopping of the rolling members relative to the treated surfaces of the isolation plates.
[0048] One class of useful polymeric materials are urea-containing polymers, for example, a polymeric material comprising polyurea.
[0049] Other polymeric materials may also be useful in providing an effective coating on the surfaces, e.g., load-bearing surfaces, of the isolation bearing plates. Examples of such other polymers include, without limitation, other urea-containing polymers (copolymers); polyurethanes, polyolefins, polyacrylates, polyacrylonitrile, polyamides, polycarbonates, polyester resins, polyethylene, polyglycols, polyisocyanates, polymethoacrylates, polymethacrylonitrile, poly(methyl acrylate), poly(methyl methacrylate), poly(α-methyl styrene), other hydrocarbon-based polymers, non-hydrocarbon-based polymers, sulfonated copolymers of ethylene and propylene, sulfonated ter-polymers of ethylene, propylene and a diene, sulfo butyl rubber, sulfo isoprene/styrene rubber, sulfo isoprene/butadiene rubber, sulfo isoprene/butadiene/styrene copolymers, sulfo isobutylene/styrene copolymers, sulfo isobutylene/para methyl styrene copolymers, and complexes of the aforementioned polymers with a vinyl pyridine co-polymer, combinations thereof and the like, which are effective in coating surfaces of isolation bearing plates to eliminate or retard sliding, skipping, skidding and/or stopping of a rolling member relative to the treated surfaces of the isolation barrier plates in a seismic isolation bearing assembly.
[0050] It may be advantageous to treat the surface of the bearing plate on which the polymeric material is to be placed to enhance the adhesion of the polymeric material to the plate surface on which the polymeric material is to be placed. For example, this plate surface may be roughened, e.g., sand blasted, or otherwise treated to increase the surface area and provide a non-smooth or roughened texture to the plate surface, relative to the original or non-treated plate surface, so that the polymeric material more strongly adheres, or is more strongly secured, to the plate surface relative to the non-treated plate surface. The thickness of the coating on the load-bearing surface of the isolation bearing is preferable in the range from about 0.5 mm to about 5 mm, or about 0.75 mm to about 3 mm, or about 1 mm to about 2 mm, or about 1.5 mm.
[0051] Seismic bearing plates having a surface wholly or partly treated with such a polymeric material may comprise part of any suitable seismic isolation bearing assembly. Without limiting the scope of the invention, examples of suitable seismic bearing assemblies may include the following.
[0052] In one example, the seismic isolation bearing assembly may be located in a seismic flooring or platform system and may comprise at least two opposing bearing plates, separated by a rigid or hard bearing element, e.g., a ball, such as a metallic ball bearing, or a roller, e.g., such as a metallic roller bearing. The rigid or hard bearing elements of two or more such assemblies may support the payload upon a frame, flooring element, or platform.
[0053] In particularly preferred examples a seismic isolation bearing comprised in a seismic flooring or platform system comprises two bearing plates, separated by a rigid bearing element. In such arrangements an upper bearing plate may be joined to a frame, flooring element, or platform, while a lower bearing plate may be placed upon or affixed to a floor, foundation, frame, or other similar support surface. A lower bearing plate may be oriented “upward”, so that when the system is at rest the rigid ball is nested at a central point on the bearing surface of the lower bearing plate. An upper bearing plate may be oriented “downward”, so that when the system is at rest the rigid ball rests within a central point on the bearing surface of the upper bearing plate.
[0054] In one example, at least a lower bearing plate comprises a polygonal outline shape other than a rectangle in a plan view. A polygonal shape, for example (but not necessarily) an octagonal shape, may be employed and can add to the stability of the seismic isolation system in at least two ways.
[0055] First, polygonal seismic isolation bearings may be assembled so that straight sides of the upper and/or lower polygonal bearing plates of at least two adjoining upper or lower isolation bearings may be joined or linked together, thereby reinforcing the stability of these bearings during a seismic event. In certain examples, a single upper or lower polygonal bearing plate may be joined to more than one adjoining bearing plate and/or to a flooring, frame, or platform element. Furthermore, when three or more isolation bearings are used in a single platform or flooring system, the frame, platform and/or flooring elements and the bearings may thus be linked together into a single reinforced structure or network in which the entire upper and/or lower bearing element array is locked together as one.
[0056] Secondly, the polygonal shape may facilitate linking the bearing plates to the frame, platform and/or flooring elements. For example, a circular isolation bearing plate has only one point (the point of tangency) at which it makes contact with a straight-edged surface. Thus, even in cases in which upper and/or lower polygonal bearing plates are not linked to each other, the joint between framing, platform, and/or flooring element and the bearing plate is made much more strong and firm when a straight edged segment of the perimeter of the bearing plate (or the bearing plate frame) is joined to a straight segment of such element.
[0057] Each of these advantages make the manufacture and assembly of seismic isolation systems comprising polygonal isolation bearings substantially easier than systems employing circular isolation bearings. Due to the straight edges of the isolation bearing plates of the present invention, seismic isolation systems can be designed to fit together more strongly and precisely than those having circular bearing plates.
[0058] Furthermore, when an isolation system employs an array of three or more, or four or more, or five or more, or six or more, isolation bearings having the same or complementary polygonal shapes, these bearings can be arranged in various ways depending on factors including, without limitation, the payload location, size, mass, and the size and/or and shape of the space in which the seismic isolation system is to be installed, in order to optimally support the load or conform with space limitations.
[0059] The polygonal bearing plates of the present invention may either be manufactured as circular bearing plates with a polygonal “frame” joined thereto by, for example, welds, appropriate fasteners (such as screws, bolts and the like). In another example, the polygonal bearing plates may be manufactured as a polygon, again, preferably surrounded by a polygonal frame.
[0060] It will be understood that the polygonal frames, bearing plates and the like may have rounded or “radiused” corners without departing from the scope of the invention. Thus the term “polygonal” or “polygon” shall be interpreted to mean “generally polygonal”; that is, comprising at least two (and preferably at least three) straight sides wherein the sum of all curves and angles totals 360°. In some cases, “polygonal” may mean any polygonal shape other than a rectangle.
[0061] The use of polygonal bearing plates greatly facilitates the manufacture and assembly of seismic isolation systems. For example, connector components can be fabricated easily of, for example, metal tubing, flat plates, or angle iron with standardized placement of connection fittings such as (without limitation) screw or bolt holes, or brackets, for being joined to the polygonal bearing plate(s) and/or framing, flooring or platform elements. These connector component/bearing plate assemblies can thus be extended for the desired length or width of the isolation system, with the length of connectors and number of bearing plates being determined, at least in part, by the anticipated mass of the payload. In particular, examples each of opposing sets of polygonal top and bottom bearing plates are linked by, and joined to, connector components to form top and bottom flooring or platform assemblies. Additionally, or alternatively, two or more adjacent polygonal top and/or bottom bearing plates may be joined to each other to form a strong and rigid isolation assembly.
[0062] In other possible configurations, the top and/or bottom isolation assembly may be constructed without the use of separate connector components. For example, the polygonal shape of the seismic bearing plates may facilitate directly joining one bearing plate to at least one adjacent bearing plate, which is joined, in turn, to at least one additional bearing plate to form a firm, mutually stabilized structure.
[0063] One or more of the bottom bearing plates may also be directly or indirectly joined to a foundation or floor. For example, one or more bearing plate may be fastened directly to the foundation using, for example, concrete anchored fasteners or an adhesive for fastening plastics or metals to concrete, such as the 3M Scotch-Weld® brands of urethane, acrylic and epoxy adhesives.
[0064] One or more of the top bearing plates are preferably directly or indirectly fastened to a platform or flooring element. For example, a top bearing plate may be fastened directly to one or more flooring support “tile” or region using bolts, screws or other similar fasteners, or may be joined to a frame for supporting the payload, bearing plate, or tiles.
[0065] In one example, the present invention is drawn to a polygonal seismic isolation bearing plate comprising:
[0066] a) a recessed hardened load-bearing surface component; and,
[0067] b) a hardened frame component, sufficiently strong to support said load-bearing surface component during use in an isolation platform or flooring system during an earthquake, said frame component being directly or indirectly joined to said load-bearing surface component; wherein, in top view, the frame component comprises a polygonal shape, for example, other than a rectangle, and wherein said frame component is structured to be joined along at least one straight edge to at least one other component of said isolation platform or flooring system.
[0068] In such a system the load-bearing surface component may be welded or otherwise securely joined to a circumferential ring (for this purpose considered part of the load-bearing surface), which can then be joined to a frame component, or may be joined directly to the frame component. The frame component is preferably polygonal in shape, and is structured to be joined to other bearing plate assemblies, or to other components of the isolation flooring or platform assembly. In a particularly preferred embodiment the polygonal shape is not a square, or not a rectangle.
[0069] In another example, the invention is drawn to a polygonal seismic isolation bearing assembly comprising:
[0070] a) a hardened ball disposed between
[0071] b) a top isolation bearing plate, and
[0072] c) a bottom isolation bearing plate;
[0000] wherein each said top and bottom isolation bearing plates comprise:
[0073] i) a recessed hardened load-bearing surface component; and,
[0074] ii) a hardened frame component, sufficiently strong to support said load-bearing surface component during use in an isolation platform or flooring system during an earthquake, said frame component being directly or indirectly joined to said load-bearing surface component; wherein, in top view, the frame component comprises a polygonal shape, and wherein said frame component is structured to be joined along at least one straight edge to at least one other component of said isolation platform or flooring system.
[0075] Preferably the frame element of one or both of the top bearing plate or the bottom bearing plate is welded or otherwise joined to its respective load-bearing surface component. As above, the frame component is preferably polygonal in shape, and is structured to be joined to other bearing plate assemblies, or to other components of the isolation flooring or platform assembly. In a particularly preferred embodiment the polygonal shape is not a square, or not a rectangle.
[0076] Additionally, either or both the top and bottom isolation bearing plates may be directly or indirectly joined to one or more other isolation bearing plate(s) in substantially the same plane. An example of indirect joining is by each bearing plate in substantially the same plane being joined to the same connector component. Another example of indirect joining is by each bearing plate in substantially the same plane being joined to a common flooring or platform component.
[0077] In another example, the present invention is directed to a seismic isolation floor or platform assembly comprising a plurality of polygonal isolation bearing assemblies, each such bearing assembly comprising:
[0078] a) a hardened ball disposed between
[0079] b) a top isolation bearing plate, and
[0080] c) a bottom isolation bearing plate;
[0000] wherein each said top and bottom isolation bearing plates comprise:
[0081] i) a recessed hardened load-bearing surface component; and,
[0082] ii) a hardened frame component, sufficiently strong to support said load-bearing surface component during use in an isolation platform or flooring system during an earthquake, said frame component being directly or indirectly joined to said load-bearing surface component; wherein, in top view, the frame component comprises a polygonal shape, and wherein said frame component is structured to be joined along at least one straight edge to at least one other component of said isolation platform or flooring system.
[0083] In the seismic isolation floor or platform assembly at least two of said plurality of polygonal isolation bearing assemblies may be joined in a manner selected from the group consisting of:
[0084] i) said top isolation bearing plates are directly or indirectly joined together, or
[0085] ii) said bottom isolation bearing plates are directly or indirectly joined together, or
[0086] iii) both said top isolation bearing plates are directly or indirectly joined together and said bottom isolation bearing plates are directly or indirectly joined together.
[0087] It will be understood that although currently preferred examples of the invention may be used in conjunction with, or as part of, a polygonal seismic isolation system, the scope of the invention is not limited by these examples. Thus a polymeric coating on the load-bearing surfaces of isolation floors, “low rise” isolation systems (in which the lower bearing is mounted in or below the floor or foundation, and any other rolling member isolation system whether using traditional circular isolation bearings or the polygonal bearings disclosed herein.
[0088] The inventions shall now be described by detailing specific, non-limiting drawings and examples.
BRIEF DESCRIPTION OF THE DRAWINGS
[0089] FIG. 1 shows one example of a finished polygonal (octagonal) isolation bearing plate of the present invention.
[0090] FIG. 2 shows an intermediate stage in the fabrication of the polygonal (octagonal) isolation bearing plate of FIG. 1 , showing certain of the components.
[0091] FIG. 3 shows a cross sectional view of the finished f a polygonal (octagonal) isolation bearing plate of FIG. 1 .
[0092] FIG. 3A is an enlarged cross-sectional view of a portion of the isolation bearing plate, shown as “ 3 A” in FIG. 3 , showing this portion of the isolation bearing plate in more detail.
[0093] FIG. 4 is a block diagram setting forth steps to provide the isolation bearing plate of FIGS. 3 and 3A in accordance with the present invention.
[0094] FIG. 5 is a diagram of one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0095] Referring now to the drawings, FIG. 1 shows one example of a finished polygonal bearing plate of the present invention, showing rear fastener holes, while FIG. 2 shows the load-bearing surfaces of the same bearing plate. FIG. 3 is a cross section of the bearing plate of FIG. 1 .
[0096] In this example, the load-bearing surface component 100 is preferably fashioned from a metal (such as stainless steel) as a circular, symmetrical item, having a central area 102 comprising a radius in cross section; see FIG. 3 . Surrounding this central area is a annular area comprising a region of constant slope 104 . The bearing surface in this example is drilled and tapped with screw holes 106 for later securing of the bearing plate to an underlying or overlaying surface, if desired. The load-bearing surface 100 is welded to a circular steel band 110 and a flat bottom plate 112 ; this assembly is then joined, for example welded, to a frame component 114 comprising lengths of a hardened material (cold rolled steel (“CRS”) in this case) formed, for example, by welding, into an octagon. As shown, each side of the frame is drilled and tapped 118 for joining to, for example, framing or connector components or other bearing plates with screws or bolts.
[0097] The assembly shown in FIG. 2 comprises eight spaces 116 (appearing substantially as triangles in the two dimensional top view of FIG. 2 ) between the steel band 110 and the frame component 114 . Filler pieces of metal are then welded to the assembly to fill in the spaces.
[0098] As shown in FIGS. 3 and 3A , load bearing surface 100 includes a sandblasted upper surface 120 which is coated with a polyurea top coating 140 .
[0099] This structure is produced by sandblasting the upper (top) surface 120 of at least the load bearing surface 100 so that the resulting sandblasted surface 130 is roughened. See FIG. 3 . When a polyurea composition is applied to this roughened surface, for example, as a liquid, dry, or flowable material, the polyurea material 140 , after being allowed to cure, set or solidify, as in the form of a film or layer and securely adheres to or is held to the roughened surface 130 . The film or layer of polyurea material may be slightly sticky or tacky.
[0100] The polyurea material film or layer 140 is sufficiently thick to be wear resistant and to remain in place and effective, for example, to avoid or reduce sliding, skidding and/or stopping of the rolling member which is placed between bearing surface 100 and a complementary bearing facing the upper surface ( 140 ) of bearing 100 . As noted elsewhere in this application, reducing or eliminating such skidding and/or stopping, provides substantial advantages.
[0101] In other examples surfaces other than the load-bearing surfaces alone of the seismic isolation bearing may be coated with the polymeric coating. For example, the entire seismic isolation bearing may be so coated.
[0102] For example, the entire isolation bearing may be sandblasted, then with a polyuria coating.
[0103] The coating may be applied by spraying the polymer onto the surface, for example, onto a sandblasted surface. An advantage of polyurea polymers such as the two-component isocyanate/resin polyurea system sold as Rhino Extreme™, 11-50 GT. The isocyanate and resin are sprayed using high pressure plural component spray equipment. The coating is 100% solids, no VOC's and no solvents, is chemically resistant, and has high tensile, tear, and elongation properties. It has a hardness (Shore D) of about 45 to 55, tensile strength of about 2800-3200 psi, tear resistance of about 500-600 ple, and a percent elongation of about 400-500.
[0104] FIG. 4 is a block diagram setting forth steps to provide the isolation bearing plate of FIGS. 3 and 3A in accordance with the present invention.
[0105] FIG. 5 shows one embodiment of the present invention.
[0106] The first and second isolation bearing plates are provided. Such plates can be conventional in size, shape and structure. Such plates are often made of hardened materials, such as steel and/or other metals.
[0107] The load bearing surfaces of each of the first and second isolation bearing plates are sandblasted, or otherwise roughened, so that a coating can be placed on, and remain on, the load bearing surfaces of the isolation bearing plates. After such surface treatment/preparation, the load bearing surfaces of both the first and second isolation bearing plates are contacted with a polymeric material, such as polyurea, to form a coating of the polymer on the load bearing surfaces of the first and second isolation bearing plates.
[0108] The first and second isolation bearing plates are assembled with a bearing member, e.g., ball, roller and the like, therebetween so that the bearing member comes into contact with the coating on the first and second isolation bearing plates, thereby reducing skidding and/or stopping of the ball or roller during operation. Such reduced skidding and/or stopping during operation results in improved operational efficiencies of the seismic isolation bearing assembly. Put another way, placing a polymeric coating on load-bearing surfaces of the first and second bearing plates, in accordance with the present invention, provides substantial benefits with regard to the operation of the seismic isolation bearing assembly relative to such an assembly without the polymeric coating on the first and second bearing plates.
[0109] The surface treatment or roughening, e.g., sandblasting, of the load bearing surfaces is effective in holding or maintaining the polymeric material coatings in place on the first and second bearing plates so that the coatings are maintained on the load bearing surfaces and are effective for longer periods of time to improve the operation of the assembly.
[0110] Although the foregoing invention has been exemplified and otherwise described in detail for purposes of clarity of understanding, it will be clear that modifications, substitutions, and rearrangements to the explicit descriptions may be practiced within the scope of the appended claims. For example, the inventions described in this specification can be practiced within elements of, or in combination with, other any features, elements, methods or structures described herein. Additionally, features illustrated herein as being present in a particular example are intended, in other aspects of the present invention, to be explicitly lacking from the invention, or combinable with features described elsewhere in this patent application, in a manner not otherwise illustrated in this patent application or present in that particular example. The the language of the claims shall solely define the invention. All publications and patent documents cited herein are hereby incorporated by reference in their entirety for all purposes to the same extent as if each were so individually denoted. | A new seismic isolation bearing assembly is disclosed. The assembly includes a first isolation bearing plate, a second isolation bearing plate, and a moveable bearing element disposed between the first and second isolation bearing plates, each of the first and second isolation plates comprises a solid material and a surface facing the other isolation plate comprising a polymeric material different from the solid material. The polymeric material is effective to enhance the operability of the assembly. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part of co-pending application Ser. No. 08/510,486, filed Aug. 2, 1995, which is a continuation-in-part of co-pending application Ser. No. 08/395,417, filed Feb. 27, 1995, which is a continuation-in-part of application Ser. No. 07/985,840, filed Dec. 3, 1992, abandoned, which is a continuation-in-part of application Ser. No. 07/921,418, filed Jul. 27, 1992, abandoned, which is a continuation-in-part of application Ser. No. 07/780,155, filed Oct. 21, 1991, abandoned, the disclosures of which are incorporated by reference hereinto.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to lock systems generally and, more particularly, but not by way of limitation, to a novel electronic lock system which is especially useful in monitoring use of the lock.
2. Background Art
In many situations, it would be desirable to have a record of who opened a lock, when the lock was opened, and for how long the lock was opened. One such situation, for example, is access to slot machine mechanisms. Another such situation is access to vending machines.
Accordingly, it is a principal object of the present invention to provide a lock system which is capable of monitoring use of a lock.
It is a further object of the invention to provide such a lock system which can record who opened a lock, when the lock was opened, and for how long the lock was opened.
It is an additional object of the invention to provide such a lock system that is compact and can be easily retrofitted to systems in which mechanical key locks are employed.
It is another object of the invention to provide such a lock system which is economical to construct.
Other objects of the present invention, as well as particular features, elements, and advantages thereof, will be elucidated in, or be apparent from, the following description and the accompanying drawing figures.
SUMMARY OF THE INVENTION
The present invention achieves the above objects, among others, by providing, in a preferred embodiment, an electronic cylinder lock, comprising: a generally cylindrical housing having substantially open and closed ends; a barrel member coaxial with and rotatable within said generally cylindrical housing and having receiving means defined at a first end thereof and disposed at said substantially open end for the insertion into said receiving means of key means, engagement of said receiving means and said key means permitting said barrel member to be manually rotated; shaft means coaxial with said generally cylindrical housing and extending through an opening defined through said substantially closed end, said shaft means having a head end disposed within said generally cylindrical housing and a threaded end extending externally from said substantially closed end for the attachment to said threaded end of locking/unlocking apparatus; a bar at least partially disposed within said head end such that rotation of said bar causes rotation of said shaft means, said bar being axially moveable within said generally cylindrical housing, and said bar being selectively engageable with a second end of said barrel member such that rotation of said barrel member causes rotation of said bar; and means to cause said bar to be disengaged from said second end of said barrel member when said electronic cylinder lock is in a locked position and to cause said bar to be engaged with said second end of said barrel member to permit said receiving means, said barrel member, said bar, and said shaft means to rotate by rotation of said key means to permit said electronic lock to be unlocked.
BRIEF DESCRIPTION OF THE DRAWING
Understanding of the present invention and the various aspects thereof will be facilitated by reference to the accompanying drawing figures, submitted for purposes of illustration only and not intended to define the scope of the invention, on which:
FIG. 1 is an exploded perspective view, partially cut-away, of an electronic lock constructed according to the present invention.
FIG. 2 is a fragmentary rear elevational view showing the latching mechanism of the electronic lock.
FIGS. 3A-3D are fragmentary rear elevational views showing the detection of unlocking of the lock.
FIG. 4 is a perspective view of a component of the electronic lock.
FIGS. 5A and 5B comprise a block logic diagram showing operation of the lock.
FIG. 6 is an exploded isometric view of another embodiment of an electronic lock constructed according to the present invention.
FIG. 7 is a fragmentary isometric view of the lock of FIG. 6 assembled and installed.
FIG. 8 is a schematic diagram illustrating the operation of the lock of FIG. 6.
FIGS. 9A and 9B are fragmentary top plan views, in cross-section, showing elements of the lock of FIG. 6 in locked and unlock positions, respectively.
FIGS. 10A and 10B are fragmentary front elevational views, in cross-section, showing elements of the lock of FIG. 6 in locked and unlock positions, respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference should now be made to the drawing figures, on which similar or identical elements are given consistent identifying numerals throughout the various figures thereof, and on which parenthetical references to figure numbers direct the reader to the view(s) on which the element(s) being described is (are) best seen, although the element(s) may be seen also on other views.
FIG. 1 illustrates an electronic lock constructed according to the present invention, generally indicated by the reference numeral 10, mounted, for example, to an existing cabinet door 12.
Lock 10 includes a face cover 20 having an integral rearwardly extending hub 22 which hub fits into a complementarily shaped double-D opening 24 defined in cabinet door 12 to prevent the rotation of the face cover and hub relative to the cabinet door. A cylindrical drive hub 30 is inserted into and rotates within member 22. Drive hub 30 has defined in the front portion thereof an opening (not shown) to accept therein a key or wrench (not shown) which may be the oval wrench described in the above-referenced application Ser. No. 08/395,417. Two drive pins 36 and 38 inserted into holes 40 and 42 defined in the rear face of drive hub 30 attach the drive hub to, in order, a first insulator 48, a communication plate 50, a second insulator 52, and a lock hub 54. Lock hub 54 is attached to a lock bar 60 by means of a screw 62, the lock bar engaging a surface, such as surface 64, for example, to prevent cabinet door 12 from being opened.
Lock 10 further includes a printed circuit board 70 having electronic circuitry, including a microprocessor and a non-volatile memory, mounted thereon and two contact wires 72 and 74 extending therefrom. An unlock solenoid 80 includes a lock plate 82 at the end thereof which engages a step 84 formed on lock hub 54 when lock 10 is in its locked position. A spring 86 biases lock plate 82 into the locked position when unlock solenoid 80 is unenergized.
All the components of lock 10, except for lock bar 60, are disposed in a housing 90 attached to the rear surface of cabinet door 12 and having a rear cover plate 92, the components being secured together and attached to the rear surface of the cabinet door by means of two screws 94 and 96 extending through rear cover plate 92 holes 100 and 102 defined through the front of the housing and into the cabinet door. A spacer 106 extends between rear cover plate 92 and the front of housing 90.
With reference also to FIG. 2, the action of unlock solenoid 80 is illustrated. Lock plate 82 is shown, in solid lines, engaging step 84 on lock hub 54 to prevent the rotation thereof. When unlock solenoid 80 is energized, lock plate 82 is withdrawn from engagement with step 84, as shown in broken lines, and lock hub 54 is free to rotate counterclockwise as indicated by the arrow, thus disengaging lock bar 60 (FIG. 1) from surface 64 so that cabinet door 12 may be opened.
When lock 10 is subsequently locked by rotating lock hub 54 and the other rotating members clockwise, the lock hub is stopped at its home position by means of engagement of stop plate 82 with step 84.
Lock 10 is arranged so that the same components may be employed for either 90-degree or 180-degree rotation of the rotating lock members. If 90-degree rotation is desired, lock bar 60 is used in the position shown, with a stop pin 120 extending forwardly of the lock bar and engaging an arcuate channel 122 defined in the rear surface of rear cover plate 92. As lock bar 60 is rotated counterclockwise during unlocking of lock 10, stop pin 120 will enter and move within channel 122. When stop pin 120 engages the upper limit of channel 122, further counterclockwise rotation of the lock bar and the other rotating components of lock 10 past 90 degrees will be prevented. If, on the other hand, 180-degree rotation is desired, lock bar 60 is removed from lock hub 54, reversed, and reattached to the lock hub, with stop pin 120 facing rearwardly, thus permitting full rotation of the rotating members of lock 10 to the 180-degree position. The 180-degree position is determined by a rotation stop pin 110, fixed in a opening 112 defined in rear cover plate 92, engaging a channel 114 defined lock hub 54, as is more clearly shown on FIG. 4. As will be understood from FIG. 4, counterclockwise rotation of lock hub 54 will terminate when rotation stop pin 110 engages wall 116 of channel 114. The selection of degree of rotation does not have to be made until lock 10 is being installed in the field.
Lock 10 is quite compact and can be easily retrofitted to installations where mechanical key locks were previously installed.
With continued reference to FIG. 1, two contact wires 72 and 74 are disposed so as to contact communication plate 50 for communication through a conductive post 130 on the communication plate, which conductive post electrically engages a contact pin on the key (not shown), as is described in the above-referenced application Ser. No. 08/395,417, for communication between the circuitry on board 70 and the key, as is also described in that application. The use of two contact wires 72 and 74 is used in the present invention to determine when lock 10 is in an unlocked position. FIG. 3A illustrates the position of communication plate 50 when lock 10 is in the locked position. Here, contact wires 72 and 74 complete an electrical path between board 70 and communication plate 50. When unlocking begins and the rotating components of lock 10 have been rotated about 30 degrees counterclockwise, as is shown on FIG. 3B, the electrical path is broken, since contact wire 74 no longer contacts communication plate 50, thus indicating an unlocked, or unlocking, condition. FIGS. 3C and 3D illustrate that no communication signal is received on contact wire 74 in either the 90-degree or 180-degree unlock positions. At all times, the communication signal is transmitted on contact wire 72.
Reference should now be made to FIGS. 5A and 5B for an understanding of the method of the present invention for monitoring use of lock 10.
The present invention contemplates the use of three keys: a master key, an audit key, and a service key.
The master key is used to write a password to the memory of lock 10 or to change a previously written password. At step 200, the master key is inserted in lock 10, power is applied to the lock at step 202, the lock responds with a request for key status at step 204 and, at step 206, information is exchanged and an unlock command given by the key to the lock, all similar to the description in detail in application Ser. No. 08/395,417.
At step 208, lock 10 determines if the key is a valid master key. If yes, the new password is written to the non-volatile memory in lock 10, at step 210, and, at step 212, time-stamped positive acknowledgment is transmitted to the key.
If step 208 determines that the key is not a valid master key, that is, it is an audit key, a service key, or an unauthorized key, step 214 determines if the password given by the key is valid. If the password is not valid, step 216 records the number of password attempts in the memory of lock 10 and step 218 determines if the number of attempts has exceeded five. If the number of attempts has exceeded 5, step 220 terminates lock responses. If the number of attempts has not exceeded five, then the procedure returns to step 204. Permitting five attempts at access filters out errors due to noise, incorrect inputting of the user's PIN, and like events.
If step 214 determines that the password is valid, step 230 clears from memory the number of prior attempts with this key. Step 232 then determines if data is requested. If data is requested, that signifies that this key is an audit key and step 234 records the fact in memory. Then the data in memory as to who unlocked lock 10, when the lock was unlocked, and for how long the lock was unlocked is transmitted to the key at step 236 and step 238 transmits a transaction completion status.
If step 232 determines that data is not requested, that signifies that the key is a service key and step 250 records in memory the key number, the date, the time, and the PIN of the user. Step 252 transmits a ready to unlock signal, solenoid 80 (FIG. 1) is activated at step 254, and an unlock timer is started at step 256. Step 258 continuously senses whether there is an unlocked condition and if it is not and step 260 determines that the unlock timer has not yet reached timeout, step 258 continues to look for unlock. If timeout is reached before unlock, the unlocking procedure is aborted and step 262 requires that the unlocking procedure restart.
When step 258 senses that lock 10 is unlocked (FIG. 3B), the transaction is noted in memory at step 270 and an unlocked timer is started at 272. Step 274 continuously detects if lock 10 is locked and, if not, the unlocked timer is periodically decremented at step 276. If unlocked timer timeout is not found at step 278, the unlocked timer continues to be decremented until timeout. Then, memory is updated at step 270 and the procedure reiterated until lock 10 is locked. This particular procedure is employed to minimize the amount of memory used. A clock signal may be received from the key for use by the unlock and unlocked timers. When step 274 determines that lock 10 is locked, step 280 advises the microprocessor to expect loss of power.
When the electronic lock of the present invention is applied to vending machines, for example, it is desirable that the locking/unlocking portion of the lock have a housing which is a 3/4-inch diameter DD cylinder lock barrel, the de facto standard in the vending machine industry. This is accomplished by separating the control portion of the lock from the mechanical/electromechanical elements of the lock and reconfiguring the latter elements, as is described in detail below. Consequently, the latter elements can be inserted directly into an existing 3/4-inch diameter, 1.9-inch long, DD cylinder lock barrel, with only minor modifications to the cylinder lock barrel.
FIG. 6 illustrates an embodiment of the electronic lock described immediately above, constructed according to the present invention, and generally indicated by the reference numeral 300. Lock 300 has elements similar in function to a number of those of lock 10 (FIG. 1) and includes a housing 302 which may be the barrel of a conventional 3/4-inch diameter, 1.9-inch long, DD cylinder lock. Elements of lock 300 which are inserted into housing 302 through the proximal end thereof are, in order: a tamper ring 304, a retainer 306, a front shaft 308, a front insulator 310, a communication commutator 312, a middle insulator 314, a solenoid commutator 316, a rear insulator 318 having a channel 319 defined therein into which channel the solenoid commutator fits, a solenoid housing 320, a solenoid 322, a solenoid return spring 324, a solenoid washer 326, a solenoid plunger 328 assembly having a rearwardly facing bar 330 disposed orthogonally to the major axis of housing 302, and a rear shaft 332 having defined therein a slot 334 disposed orthogonally to the major axis of housing 302 and dimensioned to accept therein bar 330.
Screws 340 secure solenoid 322 to solenoid housing 320 and pins 342 extending rearwardly from shaft 308 secure elements 310, 312, 314, 316, and 318 to solenoid housing 320 for common rotation of elements 304-328. All elements 308-328, generally indicated by the reference numeral 340, fit within retainer 306, with the rear face of the front shaft engaging the front face of rear shaft 332, but with bar 332 extending from the rear of retainer 306 as is described in detail below. An assembly pin 350 is insertable through housing 302 into retainer 306 to secure the retainer against rotation within the housing.
A key or wrench (not shown) is insertable through tamper ring 304, into retainer 306, and into a recess in front shaft 308. In this embodiment, if unlocking of lock 300 is not authorized, the key or wrench will simply rotate elements 308-328, without the breaking of any element(s) within the lock. A set screw 352, a detent spring 354, and a detent ball 356 are inserted into a threaded opening 358 defined through the wall of housing 302 such that the detent ball releasably engages a recess 360 defined in the outer periphery of front shaft 308 to provide a palpable "home" position for rotating elements 340 of lock 300.
Rear shaft 332 has a threaded DD portion 370 extending rearwardly thereof, which DD portion extends through a suitably dimensioned opening 371 in the rear wall of housing 302 for attachment of a lock bar 372 to the DD portion by means of a nut 374 and a lock washer 376. A rotating washer 378 disposed on DD portion 370 has flanges 390 and 392 extending from the periphery thereof, which flanges engage a stop 394 to terminate locking and unlocking rotation as lock 300 is locked or unlocked. Rotating washer 378 is reversible so that either 90-degree or 180-degree rotation of rotating elements 340 may be selected. A vertical slot 396 is defined in the rear wall of housing 302 extending across opening 371.
A printed circuit board 400 is attached to a flat side of housing 302 by means of a screw 402 or other suitable attachment means, with wipers 404, 406, and 408 extending through an opening (not shown) defined through the wall of housing 302. Wiper 404 slidingly engages communication commutator 312, wiper 406 slidingly engages solenoid commutator 316, and wiper 408 is a ground lead which slidingly engages solenoid housing 320. Leads 420 connect printed circuit board 400 through connector 422 to a controller 424, which controller is located remotely from housing 302.
FIG. 7 illustrates housing 302 mounted in a panel 430 by means of a nut 432. Panel 430 may be assumed to be part of a vending machine or a similar device. It can be seen that the electromechanical elements of lock 300 consume no more volume than a conventional key-operated cylinder lock and, were it not for printed circuit board 400 and leads 420, the lock shown on FIG. 7 would appear to be a conventional key-operated cylinder lock.
In use, and with reference also to FIG. 8, the end of a key or wrench, generally indicated by the reference numeral 440, is inserted into front shaft 308 and a contact 442 in the key engages communication commutator 312. Communication protocol similar to that shown on FIGS. 5A and 5B is now followed and, if unlocking is authorized, step 254 (FIG. 5B) causes solenoid 322 to be energized which causes bar 330 extending from the rear end of retainer 306 to engage both slot 334 in rear shaft 332 and vertically aligned cutouts 398 (only the upper cutout visible on FIG. 6) defined in the rear face of solenoid housing 320. Then, any rotation of the key or wrench will rotate lock bar 372 (FIG. 6) from a locked position to an unlocked position.
FIGS. 9A, 9B, 10A, and 10B illustrate in more detail the operation of lock 300. The elements shown on these figures have been separated slightly from their normal relative positions for greater clarity.
FIGS. 9A shows lock 300 in locked position. In the locked position, with solenoid 322 (FIG. 6) de-energized, solenoid spring 324 (FIG. 6) has driven bar 330 (FIGS. 9A and 10A) rearwardly, so that the bar engages both slot 334 in rear shaft 332 and channel 396 in the inside face of the rear wall of housing 302, thus preventing lock bar 372 from being rotated. On the other hand, rotating elements 340 (FIG. 9A) are free to rotate, as described above, without breaking any internal components of lock 300.
When solenoid 322 (FIG. 6) is energized, bar 330 is drawn forewardly, as shown on FIG. 9B, so that the bar engages slot 334 in rear shaft 332 and cutouts 398 in the rear face of solenoid housing 320. Now, rotation of rotating elements 340 by means of a key or wrench (not shown) inserted in front shaft 308 (FIG. 10B) and turned will permit rotation of lock bar 372 (FIG. 6) to an unlocked position.
As will be understood from FIG. 6, once rotating elements 340 have been rotated about 20 degrees, wiper 406 will lose contact with solenoid commutator 316 which causes the de-energization of solenoid 322 and solenoid spring 324 will attempt to drive bar 330 rearwardly in housing 306. Such is prevented, however, as will be understood with reference to FIGS. 10A and 10B. FIG. 10A shows bar engaging channel 396, as is seen also on FIG. 9A. When, however, bar 330 is withdrawn from channel 396 (FIG. 9A) and rotated (FIG. 10B), it can no longer engage slot 396 and de-energization of solenoid 322 will simply only permit the end face of the bar to slide around the inner surface of the end wall of housing 306. The opposite ends of bar 330 and channel 396 are asymmetrical with respect to the central axis of housing 306, so that the bar cannot re-engage the channel if the bar is rotated 180 degrees.
De-energization of solenoid 322, as described above, conserves power while lock 300 is in the unlocked position and the absence of current flow to the solenoid provides an indication to controller 424 that the lock is in an unlocked position.
It will thus be seen that the objects set forth above, among those elucidated in, or made apparent from, the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown on the accompanying drawing figures shall be interpreted as illustrative only and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. | An electronic cylinder lock, including: a generally cylindrical housing having substantially open and closed ends; a barrel member coaxial with and rotatable within the generally cylindrical housing and having receiving apparatus defined at a first end thereof for the insertion into the receiving apparatus of key apparatus, engagement of the receiving apparatus and the key apparatus permitting the barrel member to be manually rotated; shaft apparatus coaxial with the generally cylindrical housing and extending through an opening defined through the substantially closed end, the shaft apparatus having a head end disposed within the generally cylindrical housing and a threaded end extending externally from the substantially closed end for the attachment to the threaded end of locking/unlocking apparatus; a bar at least partially disposed within the head end such that rotation of the bar causes rotation of the shaft apparatus, the bar being axially moveable within the generally cylindrical housing, and the bar being selectively engageable with a second end of the barrel member such that rotation of the barrel member causes rotation of the bar; and apparatus to cause the bar to be disengaged from the second end of the barrel member when the electronic cylinder lock is in a locked position and to cause the bar to be engaged with the second end of the barrel member to permit the receiving apparatus, the barrel member, the bar, and the shaft apparatus to rotate by rotation of the key apparatus to permit the electronic lock to be unlocked. | 4 |
TECHNICAL FIELD
This invention relates to battery chargers, and more particularly to battery charging methods.
BACKGROUND
Battery manufacturers use the rise in temperature per unit of time when charging batteries. If one looks at the change in temperature across time, the graphical slope characteristic, known as dT/dt; may be used to determine the battery's charge capacity. As the battery fills with energy, the rise in temperature per second increases. Thus, the dT/dt measurement can be used to cause the charger to switch from rapid charge to trickle charge once a threshold change in temperature slope is detected. This dT/dt termination technique is based on the concept that batteries stay at substantially the same temperature during the charge sequence, and once fully charged, become exothermic—that is, the extra current going into the battery is no longer accepted and turns into heat. Thus, the rise in battery temperature determines when the battery is fully charged.
Two inherent problems exist with this approach. First, batteries that have separate battery contacts for the radio (discharge) and charger (charge) paths, typically contain a reverse discharge diode (in the charge path). This diode is to ensure that an external short of the external contacts won't spark or accidentally drain the battery. The problem with this diode is that it causes temperature problems in the battery. When the charge sequence starts, the rise in temperature created by the diode gets coupled to the cell temperature and can cause the charger to falsely dT/dt. Accordingly, the battery flex circuit must be designed to keep the diode far enough away from the thermistor (which is used to read the battery temperature) to avoid this problem. This typically requires a more design intensive and expensive flex design.
The second problem is that NiMH (nickel-metal hydride) batteries have exothermic characteristics and have a steep temperature slope at the start of charge and at the end of charge. This initial steep temperature slope at the start of charge can cause the charger to falsely terminate rapid charge by reading a misleading dT/dt trip point.
Accordingly, there is a need for an improved battery charging method which properly terminates rapid charge, especially for batteries that contain an additional reverse discharge protection diode, and for NiMH batteries that act exothermic especially at the beginning of the charge sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a prior art charging system.
FIG. 2 is a charging routine in accordance with the present invention.
FIG. 3 is a Voltage and Temperature Curve versus time showing that the temperature continues to rise with I=0 when battery properly ΔT/Δt terminates.
FIG. 4 is a Voltage and Temperature Curve versus time showing that the temperature does not continue to rise with I=0 when battery improperly AT/At terminates.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of the invention is now described in detail. Referring to the drawings, like numbers indicate like parts throughout the views. As used in the description herein and throughout the claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise: the meaning of “a,” “an,” and “the” includes plural reference, the meaning of “in” includes “in” and “on.”
Referring now to FIG. 1, there is shown a prior art battery charging system described in U.S. Pat. No. 5,411,816 assigned to Motorola, Inc., which is herein incorporated by reference. Charging system 100 includes a charger 102 , a battery 106 , and a radio 104 . The battery 106 includes a B+voltage terminal, a B−voltage terminal, a R c capacity terminal, and a R t thermistor terminal for battery temperature. The charger 102 includes control circuitry 130 and monitor circuitry 128 which can read and store battery parameter data through B+, R c , and R t terminals. The charging routine described herein can be incorporated into this or any number of other chargers, both in controlled and uncontrolled temperature environments.
Briefly, in this invention, a “dT/dt state with I=0” has been added to a charging algorithm after the standard dT/dt termination with the current on has occurred. In simple terms, once a dT/dt trip point has been detected, the current charging the battery is turned off. The monitoring circuitry then waits and checks the dT/dt measurement again. If the temperature is still rising, the charging circuitry knows that the battery is at full capacity as opposed to a beginning charge state.
The dT/dt state with I=0 essentially allows the battery temperature to continue to react once the current has been turned off. If the battery is fully charged when the current is turned off after the standard dT/dt, the temperature of the battery will continue to rise for a given time period, such as 3 minutes. If the battery conversely has prematurely terminated dT/dt because of additional diode heating, or because of the initial steep NiMHi temperature slope, the dT/dt with I=0 temperature rise will not occur and rapid charging can continue without prematurely terminating.
Referring now to FIG. 2, there is shown a flowchart of a charging routine 200 in accordance with the present invention. The charging routine 200 can be used in a number of charger/battery configurations, including the battery/charger configuration shown in FIG. 1 . The charging routine 200 begins at step 202 using a battery recognition scheme, known in the art, to determine the battery type, battery temperature and battery voltage. This step can be accomplished, for example, by reading the battery's R c value, the R t value, and B+value in a manner known in the art.
A battery test sequence then begins at step 204 . The testing is preferably communicated to the user by an indicator such as a red LED on the charger. Step 206 determines if the battery is good by looking at the parameters measured in step 202 and comparing them to predetermined thresholds. If the battery is determined to be bad, a fault mode is indicated, such as a combination green/red LED as shown at step 208 . If the battery is determined to be good, the routine goes on to step 210 where the battery voltage is compared to a minimum threshold value. If the battery voltage falls below the predetermined minimum threshold value at step 210 , the battery is deemed to be a dead battery and a dead battery charge mode of operation, known in the art, will commence at step 212 . Typically, dead battery operation involves rapid charging the battery to quickly get the battery voltage up to a level where the radio will operate. The battery continues to be rapid charged at step 212 and monitored at step 210 until the battery voltage reaches an acceptable value.
Once the battery voltage value reaches an acceptable value at step 210 , the routine continues to step 214 where, the charger reads the temperature of the battery and stores the value as R t1 . The charger then continues to step 216 where it then verifies if the latest battery temperature reading, R t1 , falls within a predetermined threshold, for example 10-50° Celsius. Rapid charging of the battery occurs at step 220 when the battery temperature falls within the predetermined temperature window at step 216 . If the battery temperature exceeds the maximum temperature threshold at step 216 , then the battery is too hot to rapid charge, and the charger will continue to trickle charge at step 218 . Conversely, if the battery temperature is less than the minimum temperature threshold at step 216 , then the battery is too cold to rapid charge, and the charger will continue to trickle charge at step 218 . Thus, once the battery temperature falls outside the threshold window set at step 216 , the charger will continue to trickle charge the battery until the battery cools down from a hot state or warms up from a cold state before applying rapid charge current.
Once it is determined at step 216 that the stored battery temperature falls within the predetermined temperature window, then rapid charging begins at step 220 . The charge routine then proceeds to check, at step 222 , whether the battery voltage, B+, has reached or exceeded a maximum voltage cutoff threshold, V co , or whether the battery temperature, Rt, has reached or exceeded a maximum temperature cutoff threshold, T co . These two conditions are monitored throughout a predetermined time period set at step 224 . If either of the V co or T co thresholds has been exceeded, the charger will begin to trickle charge the battery at step 226 . The trickle charge condition is preferably indicated to the user through a green LED. If neither the V co nor T co thresholds are exceeded within the predetermined time period, the charger then reads the temperature of the battery at step 228 and stores the value as R t1 . Next, the charger checks if a dT/dt slope has occurred at step 230 . The dT/dt measurement is calculated by taking the difference between the latest stored values of Rt2 (battery temperature at the start of the time period) and Rt1 (battery temp at the end of the time period) over the predetermined time period set by step 224 . If the dT/dt slope exceeds a predetermined threshold, such as a 1.8° C. rise over three minutes, then the charger will proceed to step 232 to check if the dT/dt with I=0 is positive before going on to trickle charge the battery. If the dT/dt measurement does not meet the required threshold, the charger will proceed to step 232 and store the Rt 1 temperature as Rt2. The charger will then continue rapid charging the battery and return to step 222 .
In accordance with the present invention, the charger will turn the current off in step 234 . The charger then proceeds to step 236 and reads the temperature of the battery and stores the value as R t2 . A wait state is then done for a predetermined time period set at step 238 . Once the time period set in step 238 is completed, then the charger proceeds to step 240 and reads the temperature of the battery and stores the value as R t1 . The charger proceeds to step 242 to check if dT/dt with I=0 is positive. The dT/dt with 1=0 measurement is calculated by taking the difference between the latest stored values of R t2 (battery temperature at the start of the time period) and R t1 (battery temp at the end of the time period) over the predetermined time period set by step 238 . If the dT/dt with I=0 slope is positive, then the charger will proceed to step 226 to trickle charge the battery. If the dT/dt with I=0 slope is not positive, then the charger will proceed to step 220 to restart the rapid charge sequence thereby not prematurely terminating the rapid charge sequence.
Referring now to FIG. 3, the graph of a Voltage and Temperature curve versus time shows how the temperature continues to rise at step 302 for a fully charged battery, with I=0.
Referring now to FIG. 4, the graph of a Voltage and Temperature curve versus time shows how the temperature does not continue to rise at step 402 for a battery that is not fully charged, with I=0.
By determining if the battery temperature continues to rise with the current off, after the dT/dt with current on occurs, the charger can now properly determine if the rapid charge sequence terminated properly or if it prematurely terminated the rapid charge sequence. Because of this, the charger can avoid prematurely terminating the rapid charge sequence and can continue to properly rapid charge the battery, thereby avoiding giving the user a false indication that the battery is fully charged. Furthermore this now allows for higher rapid rate currents for NiMH batteries that would have previously falsely tripped the standard dT/dt termination technique.
While the preferred embodiments of the invention have been illustrated and described, it is clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions, and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the following claims. For example, while the invention has been described as pertaining to NiMH batteries, the charging method can be equally applied to any energy storage device that has a positive temperature charge storage coefficient. | This invention is a method of charging a battery wherein false dT/dt measurements are identified. When a NiMH battery reaches full charge, the change in temperature per unit time increases. Thus, this dT/dt measurement can be used to properly terminate charging. Initial charging, however, causes a large dT/dt value that may falsely cause charging to terminate. This invention alleviates this condition by adding a wait state and then taking a second dT/dt measurement. As a fully charged battery's temperature briefly continues to rise after charging current is removed, a second, positive dT/dt measurement confirms that the battery has been completely charged to ensure proper charge termination. | 7 |
RELATED APPLICATIONS
The present application is based on, and claims priority from, Taiwan Application Serial Number 94135384, filed Oct. 11, 2005, the disclosure of which is hereby incorporated by reference herein in its entirety.
BACKGROUND
1. Field of Invention
The present invention relates to a conducting textile and related detecting device. More particularly, the present invention relates to a pressure sensible textile and related pressure sensible device.
2. Description of Related Art
With the prosperity of technology, the conducting textile comprising the conducting wefts and warps and the common weaving fiber has been developed. Integrated with the electronic transmission sensor and switches, the conducting textile may be utilized to construct the electronic sensing units and to apply broadly to the sensing devices, for example, the pressure sensing devices.
Generally, it is usually required in the structure of the pressure sensible conducting textile in the prior art at least two layers of conducting wefts and warps interlaying to each other. The conducting pressure sensible textile disclosed in U.S. Pat. No. 6,333,736 is one of the examples. Without external pressure, the two layers of the conducting wefts and warps do not contact to each other and there is no current flowing between the two layers of the conducting wefts and warps, due to the insulating fibers between the two layers as a supporting structure. In the contrary, when there is pressure applied on the conducting textile, the two layers of the conducting wefts and warps contact to each other due to the external force, the current hence flow, and the pressure is sensed. However, limited by the circuit design, it is required a structure comprising at least two layers of the conducting wefts and warps for pressure sensing. Therefore, the conventional conducting textile is thicker, and the application of the relative products is limited accordingly.
SUMMARY
A pressure sensible textile is provided. The pressure sensible textile includes at least a high-resistance conducting area and two groups of low-resistance conducting wefts and warps that intercross each other without contacting to each other. The two groups of low-resistance conducting wefts and warps both contact the high-resistance conducting area.
According to an embodiment of the present invention, one of the two groups of low-resistance conducting wefts and warps is distributed over a side of the high-resistance conducting area, and another group of low-resistance conducting wefts and warps interweaves above and below the high-resistance conducting area alternately. Besides, a group of low-resistance conducting wefts and warps is grounded to separate the high-resistance conducting area into a coupled of pressure sensible areas to increase the sensitivity of detecting the location and magnitude of the pressure.
According to another embodiment, the pressure sensible textile can be composed of a plurality of high-resistance conducting areas. A group of low-resistance conducting wefts and warps is directly contacted with each of the plurality of high-resistance conducting areas separately, while another group of low-resistance conducting wefts and warps interweaves above and below the high-resistance conducting area. Besides, an insulating area can be utilized to totally isolate the high-resistance conducting areas in order to increase the sensitivity of detecting the location and magnitude of the pressure.
The aforementioned high-resistance conducting areas are composed of high-resistance conducting wefts and warps having a specific resistance of 10 2 -10 6 Ω/cm. Some examples of the high-resistance conducting wefts and warps may comprise carbon fibers, stainless steel yarn, cupric ion fibers or other metal-plated fibers. The breaking elongation of the high-resistance conducting wefts and warps is to be greater than 30% for a better elasticity of the pressure sensible textile. A specific resistance of the low-resistance conducting wefts and warps, such as metal conducting lines or metal-plated fibers, is less than 50 Ω/cm.
According to the embodiments above, the pressure sensible textile of the present invention can determine the location and the magnitude of the pressure source simply by laterally and longitudinally interweaving the low-resistance conducting wefts and warps over the one-layered high-resistance conducting textile, and accompanying by two scanning circuits. Therefore, the thickness and the weight of the pressure sensible textile can be substantially reduced, which improves and extends the application. Some of the examples are the pressure sensible rugs at the front door of stores, the interactive perceptive dolls, the children game carpet, the direction and speed detection carpets while people walk on them, and other various applications.
These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, figures, and appended claims.
It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings 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 diagram of a pressure sensible textile and the corresponding pressure sensible device according to an embodiment of the present invention is illustrated;
FIG. 2 is a diagram illustrating the relationship between the specific resistance and the magnitude of the deformation of the high-resistance conducting warps and wefts;
FIG. 3 is a diagram of the pressure sensible textile and the corresponding pressure sensible device according to another embodiment of the present invention; and
FIG. 4 is a vertical view of one of the pressure sensible areas 310 in FIG. 3 and an insulating area 320 nearby.
DETAILED DESCRIPTION
A pressure sensible textile and the pressure sensible device are herein introduced to solve the problems in the prior art.
Reference will now be made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
For the forgoing reasons, there is a need for a thin and light pressure sensible textile and the pressure sensible device adopting it such that the applicability and the convenience may be improved.
The First Embodiment
Referring to FIG. 1 , a diagram of a pressure sensible textile and the corresponding pressure sensible device according to an embodiment of the present invention is illustrated.
In FIG. 1 , the main textile 100 of the pressure sensible textile is composed of the high-resistance conducting wefts and warps. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b are crisscross distributed over the main textile 100 . The low-resistance conducting warps 110 interweave above and below the main textile 100 , and the low-resistance conducting wefts 120 a and 120 b are fixed only at one side of the main textile 100 , for example, fixed at the upper side. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b are separated by the main textile 100 so that they do not contact to each other in order to prevent short circuits. The weaving scheme of the main textile 100 may be any conventional weaving scheme. For example, the main textile 100 may be a multi-layered structure made by weaving, or may be a warp-inserted multi-layered structure made by knitting.
The specific resistance of the aforementioned low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b is to be less than 50 Ω/cm for better current conducting. The low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a and 120 b may adopt common metal conducting lines, and preferably, softer metal-plated fibers, such as silver-plated fibers.
The specific resistance of the aforementioned high-resistance conducting wefts and warps of the main textile 100 is preferably 10 2 -10 6 Ω/cm. Moreover, the aforementioned high-resistance conducting wefts and warps need to be elastic. For example, the breaking elongation is to be greater than 30%. Therefore, the high-resistance conducting wefts and warps can not only maintain the conductivity, but also provide a delicate variation of resistance along with the deformation of the fibers. Hence the sensitivity of the pressure detection is increased. Please refer to FIG. 2 that displays the relation between the specific resistance and the stretching strain for example. When the amount of the stretching strain increases, the specific resistance of the conducting wefts and warps enlarges.
Some examples of the high-resistance conducting wefts and warps of the present invention are the conducting wefts and warps plated with a conducting layer, such like carbon fibers or cupric ion fibers, and stainless steel blended yarn or silver-plated fiber. Besides, the conducting wefts and warps of the present invention may further be conjugate spun with common weaving fibers with the present conducting wefts and warps located outside the common weaving fibers. For instance, the conducting wefts and warps of the present invention may wrap around the common weaving fibers to form conjugate fibers with a structure of wrapped yarn, while applying beaming in the weaving procedure.
In FIG. 1 , the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a are coupled to the vertical scanning circuit 130 and the lateral scanning circuit 140 through the switch 150 and the switch 160 respectively, while the vertical scanning circuit 130 and the lateral scanning circuit 140 are further coupled to the controller 170 respectively. In the pressure sensing duration, the controller 170 outputs control signals to the vertical scanning circuit 130 and the lateral scanning circuit 140 separately in order to repeatedly and alternately control the statuses of the switch 150 of the vertical scanning circuit 130 and the switch 160 of the lateral scanning circuit 140 , such that only one of the two switches 150 and 160 is at the “on” status for the benefit to detecting the location of the pressure source.
According to the pressure sensible textile provided by the embodiment of the present invention, the principle of the pressure sensation when there are only the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a , and the vertical scanning circuit 130 and the lateral scanning circuit 140 coupled to the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a , is briefly described below.
When there is a pressure source applied on the pressure sensible textile, the main textile 100 will be deformed. Since the main textile 100 is made by the elastic high-resistance conducting wefts and warps, the electric signals of the variation of the specific resistance resulted from the deformation may be transmitted to the nearest low-resistance conducting warp 110 and the nearest low-resistance conducting weft 120 a through the high-resistance conducting wefts and warps. Further, the controller 170 turns on the vertical scanning circuit 130 and the lateral scanning circuit 140 coupled to the aforementioned low-resistance conducting warp 110 and the low-resistance conducting weft 120 a alternately. Hence only the vertical scanning circuit 130 and the lateral scanning circuit 140 which are turned on can transmit the electric signals representing the specific resistance of the main textile 100 to the controller 170 .
Generally speaking, the electric signals represented the variation of the specific resistance of the main textile 100 of the low-resistance conducting warps 110 and the low-resistance conducting wefts 120 a is bigger while the location is nearer to the pressure source or the magnitude of the pressure source is bigger. Therefore, when the controller 170 receives the electric signals representing the variation of the specific resistance from different low-resistance conducting warps 110 and the low-resistance conducting wefts and warps 120 a in order, the controller 170 is able to detect the location and the magnitude of the pressure source with operation by an internal or external data processing center.
However, when the area of the main textile 100 is too big, the electric signals represented the pressure may become weak due to the high resistance of the transmission path resulted in the long transmission distance. Therefore, the low-resistance conducting wefts 120 b coupled to the ground line 180 may be utilized to separate the main textile 100 into several areas, such that the electric signals from the pressure source between the two neighboring low-resistance conducting wefts 120 b can only be transmitted out from the low-resistance conducting warps 120 a between them. Any electric signals will vanish when being coupled to the grounded low-resistance conducting wefts 120 b . Hence, no matter where the pressure source is located on the main textile 100 , the transmission range of the resulted electric signals does not exceed the area bounded by two neighboring low-resistance conducting wefts 120 b.
The Second Embodiment
Please refer to FIG. 3 . FIG. 3 illustrates a diagram of the pressure sensible textile and the corresponding pressure sensible device according to another embodiment of the present invention.
In FIG. 3 , the structure of the pressure sensible textile is different from the pressure sensible textile displayed in FIG. 1 . In FIG. 3 , the main textile 300 of the pressure sensible textile is composed of the pressure sensible area 310 formed by the high-resistance conducting wefts and warps and the insulating area 320 formed by the common yarn. The low-resistance conducting warps 330 are mainly located below the main textile 300 with a short section located above the pressure sensible area 310 in order to directly contact to the high-resistance conducting wefts and warps of the pressure sensible area 310 . The low-resistance conducting wefts 340 are mainly located above the main textile 300 and directly contact to a side of the pressure sensible area 310 . The materials of the aforementioned high-resistance conducting wefts and warps forming the pressure sensible area 310 , and the materials of the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 , are similar to those described in the first embodiment described above.
The main textile 300 mentioned above may be a multi-layered structure made by weaving, or may be a warp-inserted multi-layered structure made by knitting. Please refer to FIG. 4 . FIG. 4 illustrates a vertical view of one of the pressure sensible areas 310 in FIG. 3 and an insulating area 320 nearby. The main textile 300 is formed by weaving. As displayed in FIG. 4 , assuming the main textile 300 is made by weaving, the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 can even be integrated into the main textile 300 as a part of the main textile 300 .
Please refer to FIG. 3 again. The low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are coupled to the vertical scanning circuit 350 and the lateral scanning circuit 360 respectively through the switch 370 and the switch 380 respectively, and the vertical scanning circuit 350 and the lateral scanning circuit 360 are further coupled to the controller 390 . The control method of the vertical scanning circuit 350 and the lateral scanning circuit 360 is similar to the control method of the vertical scanning circuit 130 and the lateral scanning circuit 140 of the pressure sensible textile shown in FIG. 1 . That is, the controller 390 fast and alternately controls the statuses of the switches 370 and 380 , such that there is only one vertical scanning circuit 350 and one lateral scanning circuit 360 are electric conductive. The lateral scanning circuit 360 is further coupled to the ground line 400 to provide a low potential reference voltage of the fast scanning circuit.
Similar to the principle of the pressure sensible textile in FIG. 1 , when there is an external pressure applied to the pressure sensible textile, the main textile 300 is deformed accordingly and so as the pressure sensible area 310 . However, in FIG. 3 , the pressure sensible areas 310 of the pressure sensible textile are separated by the insulating areas 320 . Hence the electric signals representing the change of the specific resistance caused by the deformation of the pressure sensible area 310 can only be transmitted to the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 coupled to the pressure sensible area 310 that carries the pressure. Further, the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are coupled to the vertical scanning circuit 350 and the lateral scanning circuit 360 . Therefore, only when the vertical scanning circuit 350 and the lateral scanning circuit 360 coupled to the aforementioned low-resistance conducting warps 330 and the low-resistance conducting wefts 340 are electric conductive, the electric signals represented the variation of the specific resistance can be transmitted to the controller 390 .
Therefore, when the controller 390 receives the electric signals represented different specific resistances from the low-resistance conducting warps 330 and the low-resistance conducting wefts 340 coupled to the pressure sensible area 310 that carries pressure, the location and the magnitude of the pressure source can be determined precisely through a data processing center inside or outside the controller 390 .
According to the embodiments above, the pressure sensible textile of the present invention can determine the location and the magnitude of the pressure source simply by interweaving the lateral and low-resistance conducting wefts and warps over the high-resistance conducting textile, and accompanying by two scanning circuits. Therefore, the thickness and the weight of the pressure sensible textile can be substantially reduced, which improves and extends the application. Some of the examples are the pressure sensible rugs at the front door of stores, the interactive perceptive dolls, the children game carpets, the direction and speed detection carpets, and other various applications.
Although the present invention has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, their spirit and scope of the appended claims should no be limited to the description of the embodiments contained herein.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents. | A pressure sensible textile has at least a high-resistance conducting area and two groups of low-resistance conducting wefts or warps contacting the high-resistance area directly. The two groups of low-resistance conducting wefts or warps cross each other and do not contact with each other directly. Furthermore, two scanning circuits can be electrically connected to the two groups of low-resistance conducting wefts or warps. Then, a controller is added to the two scanning circuits to obtain a pressure sensible device. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION DATA
The present application is based on International Application Number PCT/US2008/051118 filed Jan. 16, 2008, and claims priority from U.S. application No. 60/880,822 filed Jan. 17, 2007, the disclosures of which are hereby incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTION
The present invention relates to a fluid level sensor and mount. More particularly, the present invention relates to a fluid level sensor that is insensitive to mineral deposits on the surface of the sensor, and a mount for the sensor.
One popular type of level sensor is a capacitive type of sensor. This sensor is used, for example, in automated machines, such as automated ice making machine. In a typical capacitive type sensor, a metal electrode in the shape of a rod is mounted vertically over a water reservoir. The reservoir is filled and emptied each machine cycle to reduce the build up of dissolved solids which can give the ice a cloudy appearance.
A small high frequency voltage is applied to the metal electrode, and when the water level in the reservoir makes contact with the rod, the capacitance of the rod to ground changes. This change is detected in a signal processing controller, and shuts off the pump filling the reservoir.
This type of sensor has at least one fundamental problem. It has been observed that when the electrode or rod becomes coated with a non-conducting material, such as a calcium carbonate mineral deposit, it acts as a dielectric, adding capacitance in series with the electrode. This additional capacitance is inversely proportional to the coating thickness. As such, as the coating builds up, the additional capacitance dominates the electrode capacitance to ground, at which point sensitivity to liquid level is lost.
In many systems, due to the monitoring and control systems, the loss of sensitivity to liquid level is not a fail safe event. For example in many automated ice making machines, if the water level cannot be detected, water will pump into the reservoir until an overload condition—based on timing—is detected and the pump is shut off. This can render the machine inoperable until service personnel remove the deposits or replace the rod. However, it has been found that cleaning can accelerate the rate of build up on rods.
Accordingly, there is a need for a fluid level sensor that is insensitive to mineral deposits on the surface of the sensor. Desirably, such a sensor is an acoustic-type sensor. More desirably, such a sensor can take various shapes and configurations and can be formed from different materials to suit a desired application. Most desirably, such a sensor is supported within a holder or support that readily accepts the sensor and that precludes the need to directly hard-wire any of the sensor components.
BRIEF SUMMARY OF THE INVENTION
A level sensor for determining the presence or absence of a liquid in contact with the sensor includes an elongate probe, a transducer operably connected to the probe and configured to produce compressional waves in the probe and circuitry for detecting acoustic energy emitted into the liquid, when liquid is in contact with the probe. The probe can be formed as a rod, a strip, a tube or other appropriate shape, and can be formed from metal, polymer, ceramic or other appropriate material.
The probe has a wet end for contact with the liquid and a dry end for electrical contact. The transducer is mounted to the dry end. When formed as a rod, the wet end of the rod can be rounded and a collar can be mounted to the rod at about the dry end. When formed as a strip, the strip has a bend therein defining a wet leg and a dry leg such that the transducer is mounted to the dry leg.
A mount for the level sensor permits mounting the sensor within a system without hard-wiring the sensor to the system. The mount includes a base having a receiving region formed in part by a plurality of depending flexible securing fingers. The fingers have locking projections that project inwardly. One or more contacts are mounted inside of and to the base and extend into the receiving region. Preferably, the contacts are spring mounted to provide positive engagement between the contacts and the transducer.
A cartridge holds the level sensor and is configured for receipt in the receiving region. The cartridge includes a circumferential recess for receiving the securing fingers. The mount is formed from a non-electrically conductive material, such as nylon or the like.
A stop wall is positioned at the about the recess to prevent over-insertion of the cartridge in the base. The cartridge includes a central longitudinal opening for receiving the level sensor and a shoulder at an end thereof the cartridge opposite the recess. A seal is present at about a juncture of the shoulder and the central opening.
When the level sensor is disposed in the cartridge and the cartridge is inserted (snapped) into the base, the level sensor is operably connected to the contact and the cartridge is releasably locked in the base.
These and other features and advantages of the present invention will be apparent from the following detailed description, in conjunction with the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings and photographs, wherein:
FIG. 1 is schematic illustration of a known capacitance-type level sensor;
FIG. 2 shows the equivalent circuit of the capacitance probe;
FIG. 3 illustrates one embodiment of a level sensor (probe) in accordance with the present invention;
FIG. 4 illustrates a cartridge-type mount for the sensor in accordance with the present invention, showing the sensor cartridge prior to insertion into the mount;
FIG. 5 is a partially exploded view of the mount of FIG. 4 ;
FIG. 6 is a cross-sectional view of the exploded illustration of FIG. 5 ;
FIG. 7 is a cross-sectional view of the assembled mount and sensor of FIG. 4 ;
FIG. 8 is a perspective illustration of an alternate embodiment of the sensor in a strip form;
FIGS. 9A-9C are snap shots of spectra of a strip-formed sensor, showing the strip in a dry condition ( FIG. 9A ); with the strip positioned in oil ( FIG. 9B ), and with the strip having a drip of oil at the end thereof ( FIG. 9C ); and
FIGS. 10A-10B are snap shots of spectra of a ceramic rod sensor, showing the rod in a dry condition ( FIG. 10A ) and with the rod positioned in water ( FIG. 10B ).
DETAILED DESCRIPTION OF THE INVENTION
While the present invention is susceptible of embodiment in various forms, there is shown in the figures and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated.
Referring briefly first to FIG. 3 there is shown schematically, a discrete level sensor 10 embodying the principles of the present invention. The sensor 10 includes a probe 12 formed as an elongate element that can be fabricated from a variety of different materials and in a variety of different shapes.
The present sensor 10 is positioned in a system so as to detect the presence or absence of a liquid in contact with the probe 12 . In one exemplary application in use in an ice making machine (not shown), the sensor 10 is position to detect the present or absence of water (and thus the level of water) in a water reservoir. In this situation, the sensor 10 is continuously subjected to cycle of wetting and drying. As such, build up of, for example, mineral deposits can occur.
It has been observed that sensors that use thickness shear and torsional modes, can, in principle, be used to sense the presence of water. A preferred embodiment of the present sensor 10 operates on the principle that compressional waves (as indicated at 14 ), unlike shear waves, propagate in water. The present sensor 10 , as seen in FIG. 3 , includes a probe that is formed as a rod in which compressional, flexural or rod modes are generated with a shear or compressional transducer 16 attached to an end 18 of the probe 12 opposite of the water sensing or wet end 20 .
These modes are trapped in the metal, ceramic or plastic (of the probe 12 ) until a fluid F touches a surface 22 of the probe 12 , at which point the out-of-plane component (as indicated at 24 ) of the wave motion converts to compressional waves. These waves then radiate into the water (as indicated at 26 ) where they dissipate.
In effect, the probe 12 acts as an antenna that radiates acoustic energy into the water. In that the energy loss can be substantial, the sensor is quite sensitive to water and other fluids contacting the bottom or sensing surface of the probe 12 , but is insensitive to mineral deposits on the sensor surface 22 . This is due to the nature of the compressional waves propagating in these deposits even more readily than shear.
Referring briefly to FIGS. 1 and 2 , as set forth above, in prior capacitance-type level sensing systems 110 a small high frequency voltage is applied to the metal electrode 112 , and when the water level in the reservoir makes contact with the rod (shown by the lines 114 in phantom), the capacitance of the rod 112 to ground (as indicated at 118 ) changes. This change is detected in a signal processing controller 116 .
This type of sensor 110 has at least one fundamental problem. It has been observed that when the electrode or rod 112 becomes coated with a non-conducting material (as at 120 ), such as a calcium carbonate mineral deposit, it acts as a dielectric, adding capacitance in series with the electrode (as indicated at 122 ). This additional capacitance is inversely proportional to the coating thickness. As such, as the coating builds up, the additional capacitance dominates the electrode capacitance to ground 124 , at which point sensitivity to liquid level is lost.
Referring again to FIG. 3 , unlike known sensors, the present sensor 10 can use either out-of-plane 24 to compressional mode conversion to create an acoustic antenna in the presence of fluids F or it can use a shear mode transducer 16 polarized along the axis A 12 of the sensor probe 12 , to create the out-of plane modes.
For example, when using a shear mode transducer 16 , the transducer 16 transmits energy into the probe 12 . The change in modes does not occur when water hits the end 20 of the probe 12 . Rather, the waves generated by (induced in) the electrode or probe 12 have nowhere to go so they bounce around in the probe. When water reaches the end 20 of the probe 12 , the waves have somewhere to go because the mode in the rod converts to compressional waves 26 in the water F. At that point, the acoustic energy starts leaking into the water, which is detected using circuitry commercially available from ITW ActiveTouch of Buffalo Grove, Ill.
In a present sensor system 10 , the transducer 16 is a standard shear mode transducer that is resonant at 1 megahertz. The burst frequency is 350 kilohertz which is determined by the dimensions of the rod and it's acoustic characteristics. A 1 MHz transducer is used because of it's ready availability, cost effectiveness and functionality. It is anticipated that compressional mode transducers can also be used. Shear is side to side motion, whereas compressional is more like a pressure wave.
The type of wave that is desirable for the level sensor 10 must be sensitive to fluid (e.g., water) to generate waves that are not sensitive to the fluid. The waves that propagate in, for example, water are compressional type waves. Compressional transducers operate on the principle that waves are formed when two surfaces move toward and away from one another in a repetitive motion.
It has been found that several advantages of the present sensor 10 over known sensing systems include: (1) a liquid level sensor impervious to mineral, grease and detergent build up on the probe; (2) insensitive to e.m.i, no radiation (creation) of e.m.i. and the ability to electrically ground the system; (3) a wide variety of metals, ceramics, PPS plastics and glass can be used for the probe 12 , so long as the material selected has the proper acoustic properties; and (4) present resonant decay processing schemes can be used to provide diagnostic information on demand.
It is anticipated that the probe 12 can be virtually any shape. In addition to the rod shape shown, other know suitable shapes include strips 40 and strips with a leg or bend 42 (as seen in FIG. 8 ), to, for example, permit mounting the transducer 16 . When shaped as a strip with a bend 42 , the bend 42 can be at any angle α provided that the radius of curvature is less than the wavelength.
Signal processing schemes can include active metal resonant decay, as well as analog to digital conversion systems and the like. It will be further appreciated that multiple parallel probes can easily be assembled in single or multiple housings to provide for multiple discrete levels by staggering the ends of the probes and that signal processing schemes can be implemented that allow for a continuous level sensor for some applications.
Other configurations and materials of sensors embodying the principles of the present invention were tested to determine the sensitivity of the sensors. In one such example, a sensor was formed as a strip 40 of stainless steel in an L-shape, having a width w 40 of 0.25 inches and a thickness t 40 of 50 mils (50 thousandths of an inch). A transducer 16 was mounted to the sensor at the short leg (dry leg) 42 of the sensor 10 .
A 360 kHz signal was generated in the transducer 16 . Snapshots of three response spectra were taken on an oscilloscope, a first ( FIG. 9A ) with the strip dry, which is the induced signal or wave, a second ( FIG. 9B ) with the strip (at the tip) positioned in oil, and a third ( FIG. 9C ) with a drip of oil coming off of the tip of the strip.
As can be seen from the spectra, there is a clear distinction in the response spectra of the dry strip and the in-oil strip. There is also a significant difference between the dry strip and the oil drip strip and between the in-oil strip and the oil drip strip. Thus, the sensor can detect the presence or absence of liquid and, importantly, the sensor can distinguish between being submerged (within a “pool” of liquid) and merely the presence of remnants of liquid on the sensor.
A sensor formed from a ceramic rod was also examined. Here, a 403 kHz signal was generated in the transducer and induced in the rod. Snapshots of two response spectra were taken on an oscilloscope. A first spectra ( FIG. 10A ) shows the ceramic rod dry and a second spectra ( FIG. 10B ) shows the ceramic rod in liquid (in this case, water). Again, there is a clear distinction in the response spectra of the dry ceramic rod and the in-liquid rod; thus, the ceramic rod sensor can detect the presence or absence of liquid. Advantageously, such a rod can be used in extremely harsh environments, such as caustic or acidic environments. It is also anticipated that the rod can be elongated to extend into areas that otherwise may be difficult to access.
In a present rod shaped probe 12 , it has been found that the tip 20 can be formed having a rounded (e.g., hemispherical) shape to prevent the accumulation of liquid at the tip and to stimulate the formation and release of any droplets from the rod. In a present probe, the radius of the hemisphere is approximately equal to the diameter of the probe 12 . It has also been found that rounding the end 20 increases the sensitivity and signal level. Without being bound to theory, it is thought that this reduction in impact and increase in sensitivity is related to acoustic mode conversion.
A novel quick-install, quick-release mount 50 for the sensor 10 is illustrated in FIGS. 4-7 . The mount 50 includes a base 52 that is configured to mount to an object, such as a wall W, near the location that is to be monitored. The base 52 has an inverted cup shape that defines a well 56 . The cup has channels 58 extending upwardly from the edge 60 to form multiple flexible fingers 62 . The fingers 62 can include a retaining lip or detent 64 at about the end of each finger 62 (at about the edge 60 ).
The base 52 is configured to house the electrical connections 66 for the sensor 10 . Accordingly, circuitry is provided on a board 68 or other carrier in the base 52 . Contacts 70 , preferably biased, e.g., spring-loaded, are positioned at an end 72 of the well 56 . Electrical conductors 66 (e.g., wires) are connected to the board 68 and extend out of the base 52 to, for example, a terminal box (not shown) for connection to a control system 88 . A cover 76 can be fitted over the board end of the base 52 to permit access to the board 68 or other components.
The probe 12 is carried by a cartridge 78 that fits into the base 52 . The probe 12 , as illustrated has a collar 28 at an upper end that surrounds the dry end 18 of the rod 12 . The transducer 16 is mounted to the dry end 18 , about central of the collar 28 .
The cartridge 78 is configured as a sleeve that fits over the rod 12 , with the rod 12 residing such that the cartridge 78 abuts the collar 28 . An isolation seal 80 , for example, an O-ring is positioned in the cartridge 78 to abut the rod 12 and collar 28 , such that the seal 80 isolates the rod 12 from the cartridge 78 and provides an environmental seal for the components (e.g., board 68 and contacts 70 ) within the base 52 . A retaining clip 82 is positioned at a lower end of the cartridge 78 to maintain the cartridge 78 positioned about the rod 12 . In a current mount 50 , the materials of construction are non-conducting, polymeric materials, such as nylon and the like. Other suitable materials will be appreciated by those skilled in the art.
In the present mount 50 , the cartridge 78 includes a circumferential shoulder 84 and a recess 86 adjacent to the shoulder 84 . The recess 86 is configured to receive the detents 64 (on the fingers 62 ) when the cartridge 78 is properly inserted in the base 52 . When inserted, as seen in FIG. 6 , the cartridge 78 snaps into the base 52 , the contacts 70 are in contact with the transducer 16 and the probe 12 is securely held in place in the mount 50 . Because the cartridge 78 snaps into place in the base 52 and there is no hard-wired connection between the sensor (transducer 16 ) and the electrical control system 88 , this arrangement provides a readily managed and maintained level sensor system 10 . Probes 12 can be easily changed by snapping cartridges 78 in and out of the base 52 to, for example, change the level at which the sensor 10 is to generate a signal (e.g., to change the liquid level to be monitored), change the material of the probe 12 , or to replace a probe 12 , without undue time and labor. In that the mount 50 uses a circumferential shoulder 84 , detents 64 and fingers 62 , the probe 78 can be inserted and/or reinserted into the mount 50 in any angular orientation and function properly.
The shoulder 84 , detents 64 and fingers 62 can be formed having shapes other than those illustrated (e.g., square or hexagonal). In addition, rather than plastic fingers, the detent function can be accomplished by other structures, such as spring, balls fitted into channels, and the like, in which case the mount can be formed of a metal.
It will be appreciated that although certain materials are disclosed and described, various other suitable material could likewise be used, for example, in fabricating the various components of the invention.
All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure.
In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular.
From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover all such modifications as fall within the scope of the claims. | A level sensor for determining the presence or absence of a liquid in contact with the sensor includes an elongate probe, a transducer operably connected to the probe and configured to produce compressional waves in the probe, and circuitry for detecting acoustic energy emitted into the liquid when liquid is in contact with the probe. A mount for the releasably holding the sensor includes a base have a receiving region formed in part by a plurality of flexible securing fingers. The fingers have locking projections extending therefrom. A contact is mounted to the base and extends into the receiving region. A cartridge supports the level sensor and is received in the receiving region. The cartridge includes a circumferential recess for receiving the securing fingers. When the level sensor is positioned in the cartridge and the cartridge is inserted into the base, the level sensor is operably connected to the contact and the cartridge is resiliently secured in the base. | 6 |
FIELD OF THE INVENTION
This invention relates to sealing rings and sealed assemblies. In particular it is concerned with sealing rings for sealing around rods in bores where the rod and bore are relatively axially movable, e.g. as in hydraulic and pneumatic cylinders. In other aspects, the invention relates to the hydraulically or pneumatically operable piston-cylinder assemblies themselves with the sealing rings installed therein.
BACKGROUND OF THE INVENTION
Sealing rings of this type are typically seated in an annular recess of the bore wall, sealing with a radially-inwardly directed sealing lip against an axially-smooth surface of a rod. This is called a "rod seal". However, the invention is also relevant to "piston seals", i.e. a situation in which the sealing ring is seated in an annular recess of the rod, sealing with a radially-outwardly directed sealing lip against an axially-smooth surface of the bore.
The present concept is particularly concerned with single-acting sealing rings, i.e. for handling high pressure from one axial direction only and therefore having in effect a high-pressure side and a low-pressure side. However the invention may have some application with sealing rings in other contexts.
A conventional single-acting sealing ring is a one-piece elastomeric unit having, on the low-pressure axial side, a continuous solid support or body portion and, on the high-pressure axial side, a divergence created by an axially-opening channel extending around the ring and separating radially-inwardly and radially-outwardly facing sealing lips, which project radially beyond the support or body portion. This description refers to the free (pre-installation) condition of the sealing ring. In the-installed condition, the support portion or body need not make contact. Under high-pressure conditions it may sometimes contact the sealed surfaces, but with a lower pressure than the sealing lip and hence without significant sealing function.
The axially-open channel between the sealing lips (or behind the sealing lip, if there is only one) is typically exposed to the fluid pressure on the high-pressure side to assist urging the sealing lip into good sealing engagement.
Another known type of sealing ring has the channel occupied by an insert with very high elasticity which "energises" the sealing lip to some extent, irrespective of the pressure conditions.
Another conventional type of seal is the solid-section or "O-ring" seal, essentially a solid annulus. These seals have the drawback that in some circumstances, the compression required to achieve a desirable degree of sealing results in an undesirably large frictional force.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide a novel type of sealing ring and sealed rod-bore installation, particularly with a view to achieving a high sealing force but with less friction and installation loading than the known "O-ring" type of seal.
In general terms, we use a sealing ring having a sealing lip extending around it and With a recess in the material of the ring behind, i.e. in axial alignment with, the sealing lip, the recess having opposed inwardly and outwardly radially-directed faces which are spaced apart in the free condition of the seal but pressed together in the installed condition of the seal to give a "positive squeeze" in the installed condition, that is, a continuity of compressed seal material between the opposed sealed surfaces at the lip.
By this means, the benefits of a "positive squeeze" are achieved, namely a substantial and self-energising seal force, but with a reduced installation force and modest friction because the radial compression of the ring involved in installation does not radially compress the full volume of rubber until the opposed faces of the recess meet.
In one specific aspect, the invention provides a sealing ring having a radially-directed face with a sealing lip projecting radially relative to an adjacent non-lip region by a distance which may be termed the sealing lip projection. There may typically be a sealing lip also on the oppositely radially-directed face of the sealing ring as well. A recess in the sealing ring body extends around behind i.e in axial alignment with, the sealing lip(s). The sealing lip projection, or total sealing lip projection if there are two opposite sealing lips, is greater than the radial width of the recess. This enables the recess to be closed radially when the sealing ring is compressed radially from the free condition to the working condition.
Alternatively stated, in another aspect, a sealing ring of the invention is radially compressible between opposed concentric cylindrical surfaces so as to press together radially-opposed faces of an internal body recess extending around behind the sealing lip(s), without compressing the radially-facing surfaces of the sealing ring into full-face contact with both of said cylindrical surfaces. This definition expresses the function of the sealing ring in an operational context, by way of a simple test.
In a further aspect, the invention provides a sealed assembly in which a radially-compressed elastomeric sealing ring seals between surfaces of a rod and a bore, the sealing ring having an annular sealing lip sealing against a said surface and an internal recess extending in the body of the sealing ring behind (i.e. in axial alignment with) the sealing lip, the internal recess being pressed shut by the radial compression; this creates positive squeeze of the ring material behind the sealing lip and gives enhanced sealing force.
In a further aspect, the invention provides a method of sealing between a rod and a bore in which a sealing ring, having in its free condition an open internal body recess, is fitted between the rod and bore surfaces to give an installed condition in which radial compression presses opposed radially-directed internal surfaces of the recess radially against one another.
The special recess of the seal is preferably open at one side, most preferably open at an axially-directed face of the ring, so that it closes easily. In many sealing rings sealing lip(s) is/are nearer to one axial side of the ring than the other; the recess may then conveniently open at that axial side, extending axially into the body of the seal behind the lip(s).
The recess may be of substantially uniform cross-sectional shape around the ring e.g. a continuous uniform channel.
The axial extent of the recess should be sufficient to provide for a significant compression force reduction behind the sealing lip(s), without jeopardising the integrity or working stability of the ring. It may however vary in dependence on the type and shape of ring involved. A typical sealing lip is the extremity of a taper or divergence of the ring surface from a supporting or body level, on one or both axial sides of the sealing lip. A support or body portion is typically solid-section. In this case, the recess preferably extends behind at least 50%, more preferably behind at least 80% of the axial extent of the outward taper or divergence, and desirably has substantially the same axial extent.
As explained, the recess must close radially in the installed condition of the ring, and for stability is therefore desirably radially narrow compared with its axial extent. Usually, its axial extent is at least twice its radial width (mean width, if the width varies). Using the above-mentioned comparison with a "total sealing lip projection", the radial width is usually less than 80%, more usually less than 70% of the total lip projection in order to give significant positive squeeze. Conversely, the radial width is usually at least 30% and more usually at least 40% of the total lip projection, to give a significant reduction in the installation force involved in compressing the ring.
The "sealing lip projection" needs to be determined in a way appropriate to a given shape of seal. Normally, it is the greatest distance by which a sealing lip projects radially beyond axially-adjacent non-lip parts of the same face of the ring. In the usual case in which an adjacent taper or divergence leads from the adjacent portion to the lip extremity, the projection can be taken as the radial extent of that taper or divergence.
As to its shape, the radially-opposed faces of the recess are preferably generally straight (in section) i.e. cylindrical or conical. They are also preferably substantially complementary. So, a slot with substantially parallel walls is suitable.
The invention may be used with piston or rod seals. It may be used with a main seal, or in an auxiliary seal e.g. for the inner (pressure side) sealing on a wiper seal.
In one particular aspect we address a new problem, namely a situation in which one or both surfaces to be sealed against is not a smooth single curve. A specific instance is envisaged where it is desired to prevent rotation of a rod around its axis in the bore e.g. where the rod carries at its end a tool whose rotational alignment must be maintained. For example, the rod might be a fluid-operated robot arm. The relative rotation might be prevented e.g. by using two cylinders side by side, and coupling their rods together at the free end. That is awkward and bulky. A simpler solution envisaged is to provide axially-extending local recesses in the surface of either the rod or the bore--preferably the rod for convenience--which can be engaged by corresponding projections on the other part.
However, the problem of how to achieve effective fluid sealing, between a smoothly curved surface and a recessed e.g. grooved surface, is a serious one.
We have found that a surprisingly effective sealing can be achieved by using the present concept, namely by
(1) providing the sealing ring with circumferentially-localised projections corresponding to the recesses grooves, to be sealed, and
(2) providing the body of the seal behind the sealing lip(s) with a recess--a channel or slot--which is open in the free condition of the ring, but closes behind the projections when the seal is installed so that its sides are squeezed together, urging the projections positively into the recesses to be sealed.
The way in which this gives effective sealing at a discontinuous corner e.g. the edge of a groove, is difficult to explain. But, it can be said that the presence of the slot or channel provides the substantial dimensional flexibility required to achieve effective sealing, while when closed giving the extra positive squeeze that is needed for the difficult sealing of the irregular surface, without causing excess very high friction overall.
Specifically, this aspect of the invention provides a sealing ring having a radially-directed sealing face with a sealing lip, at least one circumferentially localised radial projection of the sealing lips, and a channel extending circumferentially around the seal behind the sealing lip and which is positively squeezed shut, at least behind the radial projection(s), when the sealing ring seals between a rod and bore in use, with the or each projection sealing in a corresponding surface recess.
In a corresponding assembly aspect we provide a fluid-drivable cylinder assembly in which one or more radial projections, fixed relative to a cylinder bore, engage one or more respective axially-extending surface grooves of a piston rod which is axially slidable in the bore, to prevent relative rotation between the two, and in which a sealing ring seated in an annular recess of the bore seals against the grooved outer surface of the rod with a sealing face having a sealing lip, one or more respective radial projections for fitting sealingly into the one or more grooves of the rod surface, and a channel or slot in the seal behind the radial projection(s) thereof and which is radially closed by the compression of the seal between the rod and bore.
The sealing ring may have any of the preferred features mentioned above. The rod may carry a tool or manipulating device, e.g. as part of a fluid-operated robot arm.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments are now described by way of example, with reference to the drawings in which:
FIG. 1 is a diametrical and axial cross-section of a wiper seal assembly, showing the installed condition at the top and the free condition at the bottom;
FIG. 2 is an enlarged cross-section of the FIG. 1 sealing ring in its free condition as manufactured;
FIG. 3 is a corresponding cross-section showing the concept applied to a main rod seal;
FIG. 4 shows a grooved piston rod;
FIG. 5 is an axial section showing the piston rod mounted in a cylinder bore and sealed by a sealing ring;
FIG. 6 is an axial view of the sealing ring;
FIG. 7 is a radial section of the sealing ring at A--A of FIG. 6;
FIG. 8(a) shows, relatively enlarged, the section at the top of FIG. 7;
FIG. 8(b) shows, relatively enlarged, the section at the bottom of FIG. 7, and
FIG. 9 is a fragmentary view in the direction of arrow "B" of FIG. 8(b), i.e. from the opposite axial side compared to FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a wiper seal arrangement which in practice operates in conjunction with a main rod seal, not shown, for a hydraulic piston/cylinder. Such an arrangement is per se well-known; the wiper seal 3 has a conventional outward wiper lip 31 to prevent entry of dirt, and radially inner and outer hydraulic sealing lips 32,33 on the pressure side, to prevent escape of hydraulic fluid. In a manner conventional per se, the sealing ring 3 sits in an annular recess 11 of the cylinder wall 1, with the radially inner sealing lips 31,32 bearing against the surface of the rod 2 across a small clearance.
Referring now also to FIG. 2, the sealing ring 3 in its free condition is an annulus of elastomer, e.g. conventional nitrile rubber or polyurethane, of generally rectangular four-sided cross-section with an axially directed face 40 (high-pressure side) towards the fluid pressure, an oppositely axially-directed face 41 (low-pressure side), a radially-outwardly-directed face 42 (outer sealing face) having the outward sealing lip 33 bearing against the cylindrical outer wall of the bore recess 11, and a radially-inwardly-directed face 43 (inner sealing face) having the wiper lip 31 and the inward hydraulic sealing lip 32 which press against the rod 2.
On the inner sealing face 43 each of the lips 31,32 is a sharp annular edge approached by a respective main conical taper 310,320 radially inwardly from a central waist 35, the radially narrowest part of the seal body.
The low-pressure side 41 is flat and seats against the corresponding flat axially-facing wall of the bore recess 11; the wiper lip 31 projects at its radially inner edge.
The outer sealing face 42 has a plain cylindrical surface 36 at the low-pressure side, defining the outer part of a generally rectangular-section solid support body portion 38 of the sealing ring, in relation to which the various functional sealing parts can be regarded as projecting. At the high-pressure side the outer hydraulic lip 33 is defined by a radially-outward conical taper 330 from the edge of the cylindrical non-lip body surface 36 (corresponding to the central waist 35), leading to a sharp extremity 331 and an axially-short secondary taper 332 to the pressure side 40. The inner hydraulic lip 32 has a corresponding secondary taper The inner and outer hydraulic lips 32,33 are substantially opposite i.e. in axial register.
The pressure side 40 has a radially-inner region 401 and a radially-outer region 402, separated by an annular slot 50. The inner and outer regions 401,402 are slightly axially stepped. This is known, to improve fluid pressure "energising" of the sealing lips 32,33.
The annular slot 50 extends axially about half-way through the body 38 of the ring; this is substantially as far as the waist 35 where the tapers 320,330 of the sealing lips 33,32 commence. In section, its opposed internal faces 51,52 are substantially straight and axial, so that it is a substantially cylindrical slot. In fact, there is a very slight outward divergence of its opposed faces to facilitate withdrawal of a mould portion used to form the slot 50 when the ring is moulded.
The slot 50 is about three times as deep (axially) as wide (radially), and radially substantially narrower than either of the pressure side face regions 401, 402. Considering this in more detail, the mean radial width "a" of the slot is about 85% of the projection "b" of the inner hydraulic lip 32 and about 60% of the total projection "b+c" of the two hydraulic lips 32,33. For example, a ring 3 of about 60 mm diameter has a radial body thickness (of the "waist") of about 5 mm, outer and inner hydraulic lip projections of about 0.4 mm and 0.9 mm respectively, closable slot width of about 0.8 mm and slot depth of about 2.8 mm.
As seen in FIG. 1, this relative narrowness of the slot 50 enables the installed sealing ring to reach a conventional degree of radial compression of the sealing lips 32,33 without necessarily bringing the inner and outer radially-directed faces 42,43 of the ring into full all-over contact with the opposing metal (which would create high friction), at the same time squeezing shut the slot 50 and thereby achieving a positive squeeze of rubber behind the hydraulic sealing lips 32,33.
In the context of a wiper seal, this has a particular value. It is possible for fluid to become trapped under very high pressure in the space (60, FIG. 1) between the wiper seal and the main seal. This trapped pressure can sometimes blow a conventional wiper out of its housing recess. With the positive squeeze provided by the present ring, the trapped pressure that can be withstood before "blow-out" is markedly increased. At the same time, the compression force reduction allowed by the presence of the closeable slot 50 makes installation simple and keeps down friction.
As mentioned, however, the concept is not limited to this particular kind of ring. It has use in many structures where a "positive squeeze" seal can bring advantages. FIG. 3 shows a corresponding construction applied to a main rod seal 103, with axially-aligned inner and outer hydraulic lips 132,133 and the closeable slot 150 between.
The radial positioning of the slot may be varied. Generally, it will be in the central 50% of the radial width of the pressure face. In the wiper seal shown in FIGS. 1 and 2 it is well clear of the inner lip 32 to reduce the likelihood of extrusion damage if high pressure is trapped.
FIGS. 4 to 9 illustrate the concept in application to the special case of a grooved rod, where it has been found to have another special and unforeseen utility.
FIG. 4 shows a portion of a steel piston rod 502 sectioned to show that it has a circular cross-section interrupted at six peripheral locations by alignment recesses 503. Each alignment recess is a groove of uniform circular arc cross-section, extending in the axial direction along the rod 502. The six grooves are, in this embodiment, arranged as three pairs spaced regularly i.e. at 120°. The radius of the rod 502 is e.g. 2 to 3 cm.
FIG. 5 shows the rod installed as a piston rod in the cylindrical bore 501 of a cylinder housing e.g. part of a pneumatically-driven robot arm construction in which the rod 502 carries a controllable implement. Near its external opening, the bore 501 has inwardly projecting circular-section lugs 505 which engage the corresponding groove 503 of the rod and prevent the rod from rotating about its own axis relative to the bore 501, while permitting it to slide in the axial direction.
Additional elements such as wiper seals are not shown, for simplicity's sake.
An elastomeric sealing O-ring 504 is seated in a cylindrically-walled annular recess of the bore 501 at the gland, sealing against the rod 502 by an inner sealing lip 508 and against the wall of its seating recess 506 by an outer sealing lip 507.
As seen on the right of FIG. 5, the seal 504 is radially thicker at the groove 503 than at the plain portions of the rod, so that a sealing lip portion 508b projects further into the bore and into the groove 503 than the part of the sealing lip 508a sealing against the plain surface. The projecting portion is projected against extrusion by support from the lug 505.
The conformation of the seal is shown in detail in FIGS. 6 to 9.
Referring generally to FIGS. 6 to 9, the radially inwardly directed surface is substantially cylindrical on the low-pressure side at the support body 517 or "heel" of the seal, which is solid in cross-section.
From the solid support portion 517--which is about half the axial extent of the sealing ring--the inner surface has the sealing lip 508 formed firstly by an inwardly tapering slope 519 and secondly by an axially short cylindrical lip extremity 520 at the radially inmost part, which is at the high-pressure side of the ring.
A "flat" lip is usual in pneumatic seals: for a hydraulic seal a sharp edge at the dynamic seal is more usual,
On the radially outward face, the outer sealing lip 507 is likewise formed by an outwardly tapering portion 521, as in the previous embodiments.
The inwardly-directed surface has three pairs of inwardly projecting nibs 540, disposed in the same layout as the grooves 503 of the rod 502 so as to engage and seal those grooves. As can be seen from FIGS. 6 to 9, the nibs 540 have the cross-section of a circular arc. They have a non-sealing portion 541 as a bulge of the support body 517, an inwardly tapering portion 542 as a bulge on the inward taper 519 of the sealing lip 508, and a sectionally flat extremity 543 in register with the flat edge 520 of the sealing lip 508. That is, each nib 540 represents an inward bulge of the entire inner surface conformation.
The annular slot 530 extends right around the ring with uniform cross-section. As seen best in FIG. 8, it extends in from the end surface 525 for approximately half the axial thickness of the sealing ring. Radially, it is disposed nearer to the inner surface than the outer although at the nibs 540 it is more nearly half-way.
The shape of the slot 530 is generally similar to the previous embodiments. In particular, the width "a" of the slot 530 is less than the sum of the distances "b" and "c" by which the inner and Outer sealing lips 508,507 project radially beyond the non-sealing surfaces of the seal support portion 517.
The proximity of the slot 530 to the inner lip reduces the force required to flex the slot shut, and hence keeps friction low.
The closing of the slot, and hence in effect the presence of solid rubber through the thickness of the seal at the sealing lip location, provides a "positive squeeze" behind the sealing lips which, we find, can give relatively good sealing even at the very difficult angled locations at the edges of the grooves 502. The seal dimensions are selected so that the slot does not merely close, but is positively squeezed in the closed condition.
In the specific embodiment shown, suitable dimensions are as follows. Seal diameter: about 5 cm. With reference to FIG. 8(a), the sealing lip extensions "b" and "c" are each about 0.7 mm, the radial seal thickness "d" about 6 mm, axial seal thickness "f" about 7 mm and the radial width "a" of the slot 530 about 0.8 mm.
At the location of one of the nibs 540 (FIG. 8(b)) the radial seal thickness d' increases to about 7.2 mm and the lip extension c' of the inward sealing lip 508b decreases slightly to about 0.6 mm.
It will be understood that the number, location and shape of the nibs or projections may vary according to the specific context of use. Also the sectional form of the sealing lips may vary from one application to another. | A sealing ring for sealing between opposed surfaces of a bore and a rod extending axially in the bore has a recess, preferably in the form of a narrow axially-opening annular slot, behind one or mote sealing lips thereof. The dimensions of the recess are selected so that its opposed radial faces are squeezed together in the installed condition of the seal, giving a positive radial squeeze of seal material behind the sealing lips. The positive squeeze enables a stronger sealing force to be achieved, while the presence of the recess reduces overall radial compression force and hence avoids excessive friction. | 5 |
BACKGROUND OF THE INVENTION
Meter test switches, such as watthour meter test switches, are well known in the electric utility industry. Such switches operate in conjunction with other test instruments, such as ammeters, which must be inserted into the watthour meter circuit without interrupting current flow. Various switch designs have been proposed by different manufacturers. These designs, however, have certain undesirable features which the present invention eliminates.
Existing test switches of the type used for measuring current in a transformer rated kilowatthour meter use knife blade type switch sections for opening and bypassing circuits. Three different types of sections are used to provide the required test functions. These sections are generally referred to as potential (P), current test (C) and current shunt (C+) switches, like terminology being adopted hereinafter.
The P switch is an SPST switch having a threaded terminal post electrically connected to a yoke on which the knife blade pivots. To conduct current, the blade is pivoted to a position where it slides between a laterally expanding pressure contact which is electrically connected to a second threaded terminal post. The C+ switch is an SPDT switch having an electrical contact configuration similar to the P switch and a laterally expanding yoke provided with a retaining finger for limiting upward movement of the blade. The yoke of the C+ switch is connected electrically to the C switch so that current is shunted from the C+ switch to the C switch when the blade of the C+ switch is in the partially raised position contacting the yoke. The blade of the C+ switch, however, does not contact the yoke in its normally conductive position. The C switch is also similar to the P switch with the addition of a shunt connection from one of its terminals to the yoke of the C+ switch and abutting laterally expanding spring-type contacts for the insertion of a two-conductor test instrument probe. The spring contacts are so situated that the blade of the C switch does not make contact with them in any position.
Sets of the above described switches are mounted conventionally on a non-conducting base which is covered by a plastic cover when the switches are not in the "test" position. The three types of switches, P, C and C+, can be arranged in any configuration so as to satisfy the immediate needs of the user for a specific application. For example, three sets of the above-described switches and a neutral strap can be arranged on a base to measure current in a kilowatthour meter for a three-phase electrical system. However, once mounted on the base, the switches cannot be easily interchanged.
In any application, the knife blade design of the conventional test switch requires the use of multiple laterally expanding pressure connections. Due to the frequency with which the switches are opened and closed in normal use, the resistance of the contacts can vary considerably. This may result in incorrect metering or excessive heating, which could ultimately lead to destruction of the switch. When the switch is in use, with the plastic cover removed, the switch is exposed directly to the environment posing a potential hazard to the user.
The test switches suffer from other deficiencies as well. For example, the switch contacts must exhibit an extremely low, but relatively constant resistance. Yet, due to manufacturing tolerances in aligning the contacts, varying resistances often result. The resistance of each switch may also vary due to exposure of the switch to the environment. Tampering with the switches can also occur since the cover is easily removable. For example, an insulating tape can be placed over the knife blade to prevent electrical connection. This would result in an incorrect and/or lower watt hour meter reading. The current transformer core can become saturated. When saturated the voltage in the transformer coil is greatly increased which could cause the insulation in the core to break down and disintegrate causing the coil to short circuit or burn out.
Any combination of the above factors could also cause excessive heating of the switch which could warp or destroy such switch. Since the switches are mounted on a molded insulating type base, where the base constitutes the only support and alignment for the switch elements, replacement of a single switch due to malfunction or destruction while the switch is in use is impracticable without replacing the entire switch assembly.
The heating of the switch elements due to the variances in resistance can also affect the base and cause it to warp or fracture when bolted to a flat surface such as a metal plate thus requiring the replacement of the entire assembly.
The plastic cover acts as a locking mechanism for the switches because it can only be mounted on the base when all switches are in their "normal" or conducting position. This provides a check for returning the switches to their conducting position. However, the cover can be lost or damaged due to its detachability and no longer provide this check. Also, in the "test" mode, the cover is removed exposing personnel to high voltages across the contacts of the switches.
The test switches currently in use are operated in such a manner as to temporarily short-out a current transformer secondary winding so as to prevent damage to the current transformer while a calibrated current is inserted from test sources into the watthour meter current circuit. In addition the switches can be operated so that the current to the kilowatthour meter can be sampled by the insertion of a test probe into the meter test switch circuit without the necessity of breaking the circuit for each test.
SUMMARY OF THE INVENTION
The present invention is directed to a substantially different type of switch which performs the same or similar functions as the test switch already described but in a much more reliable and safe manner. The switch of the present invention reduces the number of pressure contacts to the minimum necessary and provides low contact resistance with minimal deviations. Each switch section includes two (or three) fixed conductive contacts and a pair of rotatable disks which provide a conductive bridge between the fixed contacts. Each switch section is aligned on a shaft made of insulative material having alternate square and round sections. Any number of switch sections necessary for a specific application may be strung on the same shaft and snap-fitted into an insulating base. The shaft is designed with alternating square and round portions so that the disks may be locked in the conducting position by moving the square portion of the shaft into alignment with the square center opening of the disks or allowed to freely rotate by moving the round portion of the shaft into alignment with the square center of the disks.
Rotation of the disks is controlled by a handle extending outward through a slot in the upper portion of the switch housing. When the disk is rotated to the conducting position, a tail, attached to the handle, seals the slot and protects the internal components of the switch from the environment.
Each rotatable disk is under a constant spring pressure forcing the disk inwardly against a spacing insulator. The space between the disks is sufficient to provide constant contact between the disks and the fixed contacts within the switch housing, producing a constant contact resistance. The rotating action of the disks also continually cleans the contacting surfaces by providing a wiping action. In addition, by the pair of disks contacting opposite sides of the fixed contact, an equivalent circuit of two low resistances in parallel results which further reduces the total resistence across the switch section.
Due to the enclosure of all of the conducting elements within the switch housing, the danger to service personnel of touching one of the high voltage contacts has been eliminated. It is also unnecessary to provide a cover for the entire switch assembly because each switch section is enclosed in its own housing. The switch sections are easy to install and, if necessary, replace due to the snap-fit between the housing and the base.
The individual switch sections are inserted in the base. Two tie rods which extend through the individual switch sections hold them in side by side relationship for insertion into the base. This type of assembly allows for easy repairing of defective switch sections in the field by unsnapping the switch assembly from the base, removing the tie rods and shaft from the switch sections, replacing the defective switch sections, reassembling the parts and inserting the switch assembly into the base. In addition, switch assemblies of this type can be sold as individual sections or as complete assemblies. This makes the test switch assembly of the present invention more attractive, especially in foreign markets, as it may be assembled easily on site, reducing import taxes and duties.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred, it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
FIG. 1 is a front elevation view of the test switch assembly.
FIG. 2 is a bottom plan view of the test switch assembly with the base removed.
FIG. 3 is a cross-section of a C+ switch section taken along the lines 3--3 of FIG. 1.
FIG. 4 is a cross-section of a P switch section taken along the lines 4--4 of FIG. 1.
FIG. 5 is a cross-section of a C switch section taken along the lines 5--5 of FIG. 1.
FIG. 6 is a cross-section of a C switch section taken along the lines 6--6 of FIG. 5.
FIG. 7 is a cross-section of the test switch assembly taken along the lines 7--7 of FIG. 1.
FIG. 8 is a perspective view of the central shaft.
FIG. 9 is an exploded view of the fixed contacts in a C switch section.
FIG. 10 is a perspective view of a D-type fixed contact mounting over a connection post.
FIG. 11 is a perspective view of an F-type shunting contact.
FIG. 12 is a schematic showing a set of switch connections in a single phase test circuit.
FIG. 13 is a partial cross-section of a switch section showing the snap-fit between the base and the switch section.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, wherein like numerals indicate like elements, there is shown in FIG. 1 a test switch assembly 10 in accordance with the invention. The assembly 10 includes switch sections identified by lettering. The three switch sections at the leftmost portion of the test switch are potential switches, designated P. The next space to the right of the P switches is a neutral strap, designated N. The switch section in the next position is a current test switch, designated C. In the next position is a current shunt switch, designated C+. The remaining four positions to the right contain, in this specific arrangement, alternating C and C+ switch sections. Other arrangements of switch sections are possible, the arrangement shown in FIG. 1 being exemplary only. A shaft 12 extends through each test switch section. The base 14 is adapted to receive each switch section in a snap-fit as shown in FIG. 13. A rib 16 formed on the interior of opposing side walls of the base fits into a mating notch 18 on opposite ends of each switch section. The base 14 is held onto a flat surface by means of screws or bolts 28 which pass through holes 30 in the bottom 26 of base 14. An insulating pad 32 of non conducting material fills the space between the bottom of the switch sections and the base 14 to prevent shorting of any connections on the underside of the switch sections to the bolts 28. This is because each section can be adapted to be backwired using threaded post holes exposed through the bottom of each switch section.
The assembly 10 also includes end sections 19, 20 which are adapted to snap-fit into the base in the same manner as the intervening switch sections. See FIG. 2. The end sections 19, 20 extend farther downward toward the bottom 26 of base 14 to retain the pad 32 in place. The sections 19, 20 also maintain the switch sections in alignment on a pair of threaded tie rods 22 which extend through spaced holes 24 formed in each of the switch sections and the end sections 19, 20. Retaining nuts (not shown) on each end of the tie rods 22, are used to maintain inward pressure on the switch sections to keep each of the sections in alignment.
The interconnection of a C switch section and a C+ switch section is shown in FIG. 2. This interconnection takes the form of a metal strip F, as shown in FIG. 11. One end is inserted through the bottom of the C+ switch section with the other end connected to the C switch section by means of a rivet 112.
The C+ switch, as shown in FIG. 3, has a base 34 of insulating type material. The notches 18 appear on each external side of the switch and run the entire width. The base also has two holes 24 to accomodate the tie rods 22 discussed above. Inserted through the base is the shunt strap F with its associated vertical fixed contact extending upward into the switch body through an opening 36. On either side of the switch there are two electrical connections 38, 40 each having a threaded post 42, 44, a retaining nut 46, 48, and internally threaded holes 43, 45. The threaded holes 43, 45 are used for mounting threaded posts (not shown) for electrically connecting the switch section from the back. The threaded posts would extend out from connections 38, 40 through holes 47, 49 in base 34. The nuts 46, 48 are used to electrically connect the posts 42, 44 to external wires for connection to the power source or load. The fixed contacts 50, 52 have a D-type configuration, as shown in FIG. 10, and are electrically connected to the posts 42, 44 by staking. The contacts shown in FIGS. 9 and 10 for use with the switch sections of this invention have double-D type holes in their base portions for fitting over the upright connection posts of the switch sections. Each contact is placed over the posts and fit down onto the double-D mating structure 186 on the connection. The bottom of the contact is flush against the collar 188. The mating structure 186, once the contact is in place, is mechanically compressed into the space remaining between the structure 186 and inwardly sloping sides of hole 190. The double-D hole in the contacts together with the staking maintain sufficient pressure between the posts and the contacts to keep the contacts in good electrical connection with the posts.
The contacts 50, 52 extend upward and angularly toward the center of the switch. All of the fixed contacts, F, 50 and 52 are engageable with the rotor disks 54. The disks 54 have a square center hole 56 through which the shaft 12 extends. Each disk 54 is rotated by a handle 58 which is attached to both disks. In rotating the disks 54 the handle 58 travels through a slot 60. In order to seal the interior elements of the switch section from the environment a tail 62 is attached to the handle 58. As the handle 58 is rotated to the "normal" position, the tail 62 covers the slot 60 protecting the interior of the switch from the environment, preventing dust and small particulate matter from getting inside the switch.
The disks 54 have matching substantially rectangular cut-outs 64. These cut-outs 64 are so situated on the disk so as to either engage or isolate one of the fixed contacts.
The switch, shown in phantom in its "normal" conductive position in FIG. 3, will conduct current from the terminal connection 38 through contact 50 to the disks 54. No current will flow through the contact F because the cut-outs 64 leave it isolated. The rotor 54 will conduct the current to contact 52 and to terminal connection 40. In the "test" position, shown in solid lines with the handle 58 in a vertical position, contact 52 will be isolated. Thus no current will flow through the switch to the output terminal 40. Contact F will be electrically connected through the disks 54 to contact 50 and in turn to input terminal connection 38. Contact F is also shunted to the current test switch C which function will be explained below.
Shown in FIG. 4 is a switch section generally designated P. This potential switch P greatly resembles the C+ switch in its configuration. The P switch has a similar type insulating base 66 with notches 18 on both sides running the entire width of the switch. The tie rods 22 also extend through the base of the P switch through holes 24. The P switch has two electrical connections 68 and 70, each having a threaded post 72, 74, a retaining nut 76, 78 for connecting to external wiring and internally threaded holes 73, 75. The threaded holes 73, 75 are used for mounting threaded posts (not shown) for electrically connecting the switch section from the back. The threaded posts would extend out from connections 68, 70 through holes 77, 79 in base 66. Extending into the interior of the P switch from the terminal 68 is a D-type contact 80. Similarly extending into the interior of the P switch from the terminal 70 is another D-type contact 82. Both contacts 80, 82 are connected to the terminals 68, 70 by staking as described above. The P switch also has two flat plates or disks 84 which are rotatable about the common shaft 12. The disks have a square center hole 86 through which the shaft 12 extends. A handle 88 controls the angular motion of the disks 84 and rotates the disks 84 forward through a slot 90. Attached to the rear portion of the handle 88 is a tail 92 which seals the slot when the handle 88 is rotated in the "normal" position to prevent dust or small particulate matter from entering the interior of the switch housing.
The switching function is again controlled by the rotation of the disks 84 and the cut-outs 94. The cut-outs 94, as in the C+ switch, either isolate or make connection between the rotor and a fixed contact. Because the chance of arcing is much greater in a potential-type switch than in a current-type switch the cut-outs 94 are larger and arcuate in shape in the P switch. In the phantom position the rotor is in its "normal" conducting position and will electrically conduct from the fixed contact 80 to the fixed contact 82. When rotated to the "test" position, shown with the handle 88 in a vertical position, the cut-out 94 of the rotor disk 84 will isolate the fixed contact 82 opening the circuit.
The C switch, as shown in FIG. 5, has been modified from the configuration of the C+ switch shown in FIG. 3 to accept a current test probe. The C switch has a similar type insulating base 96 with notches 18 running the entire depth of both sides of the switch. Tie rods 22 also extend through holes 24 in the C switch base 96. On either side of the switch housing there are similar terminals 98, 100 with threaded posts 102, 104, retaining nuts 106, 108 for connecting to external wiring, and internally threaded holes 103, 105. The threaded holes 103, 105 are used for mounting threaded posts (not shown) for electrically connecting the switch section from the back. The threaded posts would extend out from connections 98, 100 through holes 107, 109 in base 96. All of the contacts to be described in relation to the C switch are staked over the posts 102, 104 to hold them in continuous electrical contact with the terminals 98, 100. Extending into the switch housing from the terminal 98 is a fixed contact D which extends upwardly and angularly toward the center of the switch. Also extending into the switch housing from terminal 98 is a spring contact C. Contact C abuts fixed contact A which extends into the switch housing from the opposite terminal 100. The contact C is configured so that it can spring away from contact A when a current probe 110 is inserted between them. Also extending into the switch housing from terminal 100 is a contact B. FIG. 9 shows an exploded view of the contact configuration of the C switch. The A contact overlays and is in electrical connection with the B contact. As shown in FIG. 5, the D contact overlays and is in electrical connection with the C contact. Referring again to FIG. 5, the F contact is electrically connected to the C contact by means of a rivet 112 which extends through an opening 114 between the interior of the switch housing and a channel 25 in the base 96.
The C switch has a pair of flat plates or disks 116 which are rotatably movable around the shaft 12. The center portion of the rotor disks 116 of the C switch have a similar square center hole 118 through which the shaft 12 extends. A handle 120 is connected to the rotor disks 116 and is movable through a slot 122. Attached to the rear portion of the handle 120 is a tail 124 which seals the slot when the handle 120 is rotated to the "normal" position to protect the internal elements of the switch from the environment, particularly from dust and other small particulate matter. The rotor disks 116 of the C switch have similar cut-outs 126 to the substantially rectangular cut-outs 64 in the C+ switch. In addition, the rotor disks 116 have a portion removed to match the step 128 so that the rotary disks 116 are concealed within the switch housing when in the "test" position.
Shown in phantom is the "normal" position of the rotor disks 116. In the "normal" position the disks 116 conduct current from the fixed contact D to the fixed contact B. When the disks 116 are rotated to the "test" position, shown with the handle 120 in a vertical position, contact B is isolated and no current is conducted through the disks 116. However, current can flow from the C+ switch through the shunt F back through the terminal connection 98 or through the abutting C and A contacts. With the rotor disks 116 and handle 120 in the "test" position, the current test probe 110 can be inserted through an opening 130 in the step 128. The probe 110 consists of a flat non-conducting spacer portion 132 which separates conductors 134, 136. The conductors are insulated from each other and are mounted on opposite sides of the non-conducting spacer 132. Each of these conductors 134, 136 is connected through a wire to a test instrument. Contacts C and A are designed such that when test probe 110 is inserted there exists a make-before-break electrical connection between contacts C, A and conductors 134, 136 as more fully described hereinafter.
The configuration of the disks 116 on the shaft 12 is shown in FIG. 6 and is exemplary of the interior mounting of the other switch sections. Springs 138, 140 presses the disks 116 inwardly against an insulating spacer 142. The peripheral region between the disks 116 is sufficient to accommodate the passage of any of the fixed contacts between the disks 116. By rotating the disks 116 a wiping action is created across the fixed contacts cleaning both the contacts and the disks as well as making electrical connection thereto.
Referring to FIG. 8, the shaft 12 made of a non-conductive material can be seen having both a round portion 144 and a square portion 146 alternating over its entire length. The shaft 12 is retained by the housings 145, 147 (FIG. 1) which hold it in a fixed position so that it is not rotatable about its axis. The shaft 12 is slidably moveable from side to side. Such movement is controlled by a handle 148. The handle 148 is connected to the shaft 12 through an opening in the housing in the end section 20. The housing 147 is axially aligned with the shaft 12. Housing 145, on end section 19, is also axially aligned with shaft 12. The internal dimensions of housing 145 match the external dimensions of the square portions 146 on shaft 12 so that the shaft 12 can be pushed toward housing 145 keeping the switch sections from rotating as more fully described hereinafter. The shaft 12 can be locked in this position by a retaining wire inserted through one or both holes 149, 150. The holes 149, 150 extend through each of the housings 145, 147 and the shaft 12 and receive a retaining wire to keep the shaft from being pulled by handle 148 outward unlocking the switch sections. The retaining wires are held in position conventionally by lead tags attached to both ends of each wire. See FIG. 1.
Referring to FIG. 7, there is shown the interrelationship of each type of switch section to the common shaft 12. When the switches are in their "normal" conducting position the square center portions of each of the switches come into alignment with the square portions 146 of the shaft 12. When this occurs the shaft 12 may be slidably extended from one extreme position into the switch assembly in a sideways direction to engage each of the square center portions of each of the switches, thus locking them in the conducting position. In order for the switches to be rotated to the "test" position, the shaft 12 must be slidably moved to its other extreme position where the square center portions of each of the switches are engaged with the round portions 144 of the shaft 12. This enables the switches to be freely rotated to the "test" position. The round portions 144 of the shaft 12 are constructed so that at four points along its circumferential measurement it is tangent to the adjoining sides of the center square portions of each of the switch sections to prevent wobbling of the rotor disks.
The schematic drawing of FIG. 12 shows a test switch configuration for a single phase of a kilowatthour metering circuit of a three phase power system. Such a power system is usually of a sufficiently high current and voltage that conventional watthour meters will be damaged if applied directly. A typical line source 152 would be 7200 V, 600 A. A potential transformer 154 reduces the voltage at the output of its secondary coil to 120 V. A secondary current transformer coil 156 acts in the same manner as the transformer secondary and reduces the current to 5 A. The current coil 156 is normally operated at extremely low flux densities and is usually a toroidal core having a large number of windings. At the reduced voltage and current levels a kilowatthour meter can now be connected without damage to the meter. However, in order to test the accuracy of the meter or determine whether there is damage to the input circuitry a test switch assembly 158, designated by dashed lines is inserted between the output of the transformers and the input of the meter.
Referring to FIG. 12, there is shown within the box 158 a single set of switch sections necessary to test one phase of a three phase watthour meter. The switches are shown in their "normal" conducting positions where the watthour meter 160, designated by dashed lines, measures the energy being transferred to the load. One end of the secondary coil of transformer 154 is connected to a P switch through a D contact 168. When the P switch is closed voltage will flow through another D contact 170 through the potential coil 162 of the watthour meter returning through the neutral strap N to the other end of the secondary coil of the transformer 154. The two current switches, C and C+, are connected to either side of the current coil 156. One side of the current coil 156 is connected to D contact 172 of the C+ switch. When in the normally conductive position the C+ switch will conduct current through D contact 174 to the current element 164 of the watthour meter. The other end of the current coil 156 is connected through the C switch shown in a square designated by dashed lines. The current enters the switch from the current coil 156 through D contact 176. In constant electrical connection with the D contact 176, as previously described, is the shunt F and the C contact 180. When the C switch is in its "normal" conducting position, current flows from D contact 176 to B contact 178 which is also in continuous electrical contact with the A contact 182. B contact 178 is connected to the other end of the current element 164 thus completing the current circuit.
When beginning the test procedure for testing the current flow to the watthour meter, the C+ switch is opened, disconnecting D contact 174 and connecting contact F to contact 172. This is done by rotating the rotor disks 54 of the C+ switch to the test position. In rotating the disks 54 the connection to the F contact is completed before the D-type contact 52 is isolated (D contact 172 in FIG. 12). The shunt F, being placed in the current circuit by the rotation of the C+ switch, shorts out the secondary current transformer coil 156, current being shunted through the switch rather than the watthour meter. The current test switch C can now be opened without danger to the secondary coils of the transformer. Without the shunt F, the opening of the current circuit between D contact 176 and B contact 178 of the current test switch C could saturate the core of the transformer 154 and puncture the core insulation as described above if the C contact 180 and A contact 182 were separated. Now that the current transformer coil 156 has been shorted by the shunting of the current through contact F of the current shunt switch C+, the current test switch C can be opened. The opening of the C switch enables service personnel to insert the current test probe 110 through the opening 130 in the step 128 of the C switch. Inserting the probe 110 engages it with the A contact 182 on one side and the C contact 180 on the other. The C+ switch is again rotated to its normally closed position to provide for current flow through the current element 164 of the watthour meter 160. Current now flows from the current transformer coil 156 to the current test switch C through the C contact 180 to one conductor 136 of the test probe 110 through a connected wire to one side of a test instrument such as ammeter 166. The other side of the ammeter 166 is connected through a wire to the other conductor 134 of the test probe 110 which is in contact with A contact 182 of the current test switch C. The A contact 182 now serves as the connection to one side of the current element 164 of the watthour meter. In this way an accurate measure of current flow can be made while the circuit is in operation by reading the ammeter.
To disconnect the test instrument, the test probe 110 is removed from the opening 130 causing the C contact to spring toward the A contact keeping the current path closed. As the probe 110 is withdrawn, a boot 184 at the bottom portion of the spring of the C contact contacts the facing lower portion of the A contact retaining the current flow between the A and C contacts. See FIG. 9. After the probe 110 has been removed the current test switch C is rotated to its "normal" conductive position, the shaft is returned to its locking position and the retaining wires are inserted through the holes 149, 150.
The switch sections have alternative uses. One of these uses is to calibrate the watthour meter. To accomplish this, all of the switch sections P, C and C+ are rotated to the "test" position. This procedure isolates the potential transformer coil 154 and shorts the current transformer coil 156 as described above and open ends the potential coil 162 and the current element 164 of the watthour meter. A calibrated external source is now connected to the meter to impress a voltage across neutral strap N and D contact 170. A current source is supplied across D contact 174 and B contact 178. The watthour meter can now be calibrated in accordance with the external source. When the watthour meter has been calibrated, the external source is disconnected and the switches are returned to the "normal" conducting positions.
The present invention provides for a modular type test switch assembly which can be assembled and/or disassembled on site for easy repair or replacement of one or more burned out or broken switch sections. The ease with which the switches can be disassembled also allow for rearrangement of the sections or addition of new sections to the assembly without resort to total replacement of the switch assembly. The present invention also provides a locking feature which is not based on whether the cover of the switch is on or off but rather on the positions of the switch sections when returning the test switch assembly to normal operation. In order to insert the retaining wire, the shaft must be in its locked position. The present invention also provides for the use of a pair of rotatable disks, which can be made of either conducting or nonconducting material for bridging the contacts in the switches. If a non conducting disk is used, electrically conducting facing can be applied to the disk to provide a bridge between the contacts. The disks are so designed as to make contact before contact is broken when rotated. This does not apply to the P switch which is a single pole single throw type. In addition, these disks, being in parallel electrical relation to each other, provide a very low resistance so as to comply with the meter requirements of low resistances across the switches. Finally, the present invention provides for constant protection from the environment by sealing the switches when in the "normal" conducting state.
The present invention may be embodied in other specific forms without departing from the spirit of essential attributes thereof and, accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention. | An electrical test switch having a pair of spaced conductive rotors provided with matching cut-outs, the rotors being movable between a "normal" position and a "test" position. At least two spaced conductive contacts extend within a region between the rotors. The cut-outs and the conductive contacts are arranged so that the contacts wipe against the rotors when the rotors are in the "normal" position and at least one of the spaced contacts is aligned with the cut-outs when the rotors are in the "test" position. A shaft locks the switch in the "normal" position until manually released. | 7 |
TECHNICAL FIELD
This invention relates generally to cryogenic rectification and more particularly to cryogenic air separation employed with a blast furnace system.
BACKGROUND ART
The operators of blast furnaces have been switching to powdered coal injection to reduce the amount of coke necessary for the production of iron from iron ore. With powdered coal injection the air to the blast furnace, known as the blast air, must be enriched with oxygen in order to maintain the blast furnace production rate. A conventional method for enriching the blast air is to mix it with some high purity oxygen, having a purity of about 99.5 mole percent, which is generally available from an air separation which produces the oxygen for use in steel refining operations. Alternatively, lower purity oxygen may be employed to enrich the blast air. In either case, the cost of the oxygen is an important consideration in the economics of the production of the hot metal from the blast furnace.
Accordingly, it is an object of this invention to provide a system for enriching the blast air to a blast furnace with oxygen which is more efficient than heretofore available systems.
SUMMARY OF THE INVENTION
The above and other objects which will become apparent to those skilled in the art upon a reading of this disclosure are attained by the present invention one aspect of which is:
A method for producing oxygen-enriched blast air comprising:
(A) compressing air to produce blast air;
(B) dividing the blast air into a blast air portion and a feed air portion;
(C) at least partially condensing the feed air portion and passing the resulting feed air into a double column comprising a higher pressure column and a lower pressure column;
(D) producing intermediate oxygen by cryogenic rectification within the double column and passing intermediate oxygen from the double column into a side column;
(E) separating intermediate oxygen by cryogenic rectification within the side column into oxygen product fluid, having an oxygen concentration which exceeds that of the intermediate oxygen, and remaining vapor;
(F) passing remaining vapor from the side column into the lower pressure column of the double column;
(G) vaporizing some oxygen product fluid by indirect heat exchange with the feed air portion to carry out the said at least partial condensation of the feed air portion; and
(H) withdrawing oxygen product fluid from the side column and combining withdrawn oxygen product fluid with the blast air portion to produce oxygen-enriched blast air.
Another aspect of the invention is:
Apparatus for enriching blast air with oxygen comprising:
(A) a blast air blower having an output line;
(B) a side column having a bottom reboiler;
(C) a double column comprising a first column and a second column;
(D) means for withdrawing column feed from the output line, and passing the column feed to the bottom reboiler and from the bottom reboiler into the first column;
(E) means for passing fluid from the lower portion of the second column into the side column;
(F) means for passing fluid from the upper portion of the side column into the second column;
(G) means for withdrawing enriching fluid from the side column; and
(H) means for passing enriching fluid from the side column into the output line at a point downstream of the point where column feed is withdrawn from the output line.
A further aspect of the invention is:
A method for producing oxygen-enriched blast air comprising:
(A) compressing air to produce blast air;
(B) dividing the blast air into a blast air portion and a feed air portion;
(C) at least partially condensing the feed air portion and passing the resulting feed air into a double column comprising a higher pressure column and a lower pressure column;
(D) producing lower purity oxygen by cryogenic rectification within the double column and passing first lower purity oxygen from the double column into a side column;
(E) separating first lower purity oxygen by cryogenic rectification within the side column into higher purity oxygen fluid, having an oxygen concentration which exceeds that of the first lower purity oxygen, and remaining vapor;
(F) passing remaining vapor from the side column into the lower pressure column of the double column;
(G) vaporizing some higher purity oxygen fluid by indirect heat exchange with the feed air portion to carry out the said at least partial condensation of the feed air portion; and
(H) withdrawing second lower purity oxygen from the double column and combining withdrawn second lower purity oxygen with the blast air portion to produce oxygen-enriched blast air.
Yet another aspect of the invention is:
Apparatus for enriching blast air with oxygen comprising:
(A) a blast air blower having an output line;
(B) a side column having a bottom reboiler;
(C) a double column comprising a first column and a second column;
(D) means for withdrawing column feed from the output line, and passing the column feed to the bottom reboiler and from the bottom reboiler into the first column;
(E) means for passing fluid from the lower portion of the second column into the side column;
(F) means for passing fluid from the upper portion of the side column into the second column;
(G) means for withdrawing enriching fluid from the second column; and
(H) means for passing enriching fluid from the second column into the output line at a point downstream of the point where column feed is withdrawn from the output line.
As used herein, the term "column" means a distillation or fractionation column or zone, i.e., a contacting column or zone wherein liquid and vapor phases are countercurrently contacted to effect separation of a fluid mixture, as for example, by contacting of the vapor and liquid phases on a series of vertically spaced trays or plates mounted within the column and/or on packing elements such as structured or random packing. For a further discussion of distillation columns, see the Chemical Engineer's Handbook fifth edition, edited by R. H. Perry and C. H. Chilton, McGraw-Hill Book Company, New York, Section 13, The Continuous Distillation Process. The term, double column is used to mean a higher pressure column having its upper end in heat exchange relation with the lower end of a lower pressure column. A further discussion of double columns appears in Ruheman "The Separation of Gases", Oxford University Press, 1949, Chapter VII, Commercial Air Separation.
Vapor and liquid contacting separation processes depend on the difference in vapor pressures for the components. The high vapor pressure (or more volatile or low boiling) component will tend to concentrate in the vapor phase whereas the low vapor pressure (or less volatile or high boiling) component will tend to concentrate in the liquid phase. Partial condensation is the separation process whereby cooling of a vapor mixture can be used to concentrate the volatile component(s) in the vapor phase and thereby the less volatile component(s) in the liquid phase. Rectification, or continuous distillation, is the separation process that combines successive partial vaporizations and condensations as obtained by a countercurrent treatment of the vapor and liquid phases. The countercurrent contacting of the vapor and liquid phases is generally adiabatic and can include integral (stagewise) or differential (continuous) contact between the phases. Separation process arrangements that utilize the principles of rectification to separate mixtures are often interchangeably termed rectification columns, distillation columns, or fractionation columns. Cryogenic rectification is a rectification process carried out at least in part at temperatures at or below 150 degrees Kelvin (K).
As used herein, the term "indirect heat exchange" means the bringing of two fluid streams into heat exchange relation without any physical contact or intermixing of the fluids with each other.
As used herein the term "bottom reboiler" means a heat exchange device which generates column upflow vapor from column bottom liquid.
As used herein, the terms "turboexpansion" and "turboexpander" mean respectively method and apparatus for the flow of high pressure gas through a turbine to reduce the pressure and the temperature of the gas thereby generating refrigeration.
As used herein, the terms "upper portion" and "lower portion" mean those sections of a column respectively above and below the mid point of the column.
As used herein, the term "feed air" means a mixture comprising primarily nitrogen and oxygen, such as ambient air.
As used herein the term "blast furnace" means a furnace, generally used for the reduction of iron ore, wherein combustion is forced by a current of oxidant, i.e. the blast air, under pressure.
As used herein the term "blast air blower" means a turbocompressor that provides compressed feed air for blast furnace operation and for a cryogenic air separation plant.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of one preferred embodiment of the invention.
FIG. 2 is a schematic representation of another embodiment of the invention.
FIG. 3 is a schematic representation of another preferred embodiment of the invention wherein lower purity oxygen from the lower pressure column is used to enrich the blast air.
The numerals in the Drawings are the same for the common elements.
DETAILED DESCRIPTION
The invention comprises the integration of a cryogenic air separation plant with a blast furnace system. In the practice of the invention, the base load feed air compressor, which is a standard item of conventional cryogenic air separation plants, is eliminated. The feed air to the cryogenic air separation plant is taken from the blast air blower of the blast furnace system and enriching oxygen from the plant is passed into a downstream portion of the blast air train. The invention may also be used to produce another oxygen product at a higher purity than the enriching oxygen used with the blast air.
The invention will be described in detail with reference to the Drawings.
Referring now to FIG. 1, air 25 is compressed in blast air blower 125 to produce blast air 126 which is passed out of blower 125 in the blast air blower output line which runs from the blower ultimately to the blast furnace. Blast air 126 has a pressure within the range of from 35 to 100 pounds per square inch absolute (psia). The blast air is divided into blast air portion 127, comprising from 50 to 90 percent of blast air 126, and feed air portion 128, comprising from 10 to 50 percent of blast air 126. The feed air portion is withdrawn from the output line as the column feed. If desired, additional compressed air from an auxiliary compressor may be added to feed air portion 128. Feed air portion 128 is then cooled by passage through cooler 26 to remove heat of compression. Thereafter the pressurized feed air 27 is cleaned of high boiling impurities, such as water vapor and carbon dioxide, by passage through purifier 28 and resulting feed air stream 1 is cooled by indirect heat exchange with return streams in main heat exchanger 70. A minor portion 2, generally comprising from 2 to 20 percent of feed air portion 128, is turboexpanded through turboexpander 80 to generate refrigeration, further cooled by passage through heat exchanger 71 and passed into lower pressure column 200. Another portion 36 of feed air stream 1, generally comprising from 15 to 45 percent of feed air portion 128, is taken from stream 1 as a sidestream upstream of main heat exchanger 70, compressed through compressed 37, cooled through cooler 38, at least partially condensed, such as through main heat exchanger 70, and passed as stream 30 through valve 56 into higher pressure column 100 at or above the point where main feed air stream 29 is passed into column 100.
Portion 3, generally comprising from 35 to 83 percent of the feed air portion, is passed through bottom reboiler 350 which is usually located within side column 300 in the lower portion of this column. Within bottom reboiler 350 the compressed feed air is at least partially condensed and thereafter the resulting feed air stream 29 is passed through valve 50 and into higher pressure column 100.
Higher pressure column 100 is the first or higher pressure column of the double column which also comprises second or lower pressure column 200. Higher pressure column 100 operates at a pressure generally within the range of from 30 to 95 psia. Within higher pressure column 100 the feed air is separated by cryogenic rectification into nitrogen-enriched vapor and oxygen-enriched liquid. Nitrogen-enriched vapor is passed in stream 4 to main condenser 250 wherein it is condensed by indirect heat exchange with lower pressure column 200 bottom liquid. Resulting nitrogen-enriched liquid 31 is divided into streams 6 and 5. Stream 6 is passed into column 100 as reflux and stream 5 is cooled by passage through heat exchanger 72 and passed through valve 52 and into column 200 as reflux. Oxygen-enriched liquid is withdrawn from the lower portion of column 100 as stream 7, cooled by passage through heat exchanger 73 and then passed through valve 51 and into column 200. Column 200 operates at a pressure less than that of column 100 and generally within the range of from 16 to 25 psia. Main condenser 250 can be the usual thermosyphon unit, or can be a once through liquid flow unit, or can be a downflow liquid flow arrangement.
Within lower pressure column 200 the various feeds into this column are separated by cryogenic rectification into nitrogen-rich vapor and intermediate liquid oxygen. Nitrogen-rich vapor is withdrawn from the upper portion of column 200 as stream 8, warmed by passage through heat exchangers 72, 73, 71 and 70, and removed from the system as stream 33 which may be released to the atmosphere as waste or may be recovered in whole or in part. Stream 33 will generally have an oxygen concentration within the range of from 0.1 to 2.5 mole percent with the remainder essentially all nitrogen. Intermediate oxygen liquid, having an oxygen concentration within the range from 50 to 85 mole percent, is withdrawn from the lower portion of second or lower pressure column 200 and passed as stream 10 into the upper portion of side column 300.
Side column 300 operates at a pressure which is similar to that of lower pressure column 200 and generally within the range of from 16 to 25 psia. Within side column 300 the descending intermediate liquid oxygen is upgraded by cryogenic rectification against upflowing vapor into oxygen product fluid and remaining vapor. Some or all of the remaining vapor, generally having an oxygen concentration within the range of from 20 to 65 mole percent and a nitrogen concentration within the range of from 30 to 80 mole percent, is passed in stream 13 from the upper portion of side column 300 into lower pressure column 200.
The oxygen product fluid, having an oxygen concentration which exceeds that of the intermediate oxygen liquid and is within the range of from 70 to 99 mole percent, collects as liquid in the lower portion of side column 300 and at least a portion thereof is vaporized by indirect heat exchange against the condensing compressed feed air portion in bottom reboiler 350 which may be of the conventional thermosyphon type or may be a once through or downflow type unit. This vaporization serves to generate the upflowing vapor for the separation of the intermediate liquid oxygen within side column 300. The oxygen product fluid, which is used as the enriching fluid for the blast air, may be withdrawn from column 300 as gas and/or liquid.
In the embodiment illustrated in FIG. 1, the oxygen product fluid is withdrawn from column 300 as liquid. Oxygen product liquid stream 12 is increased in pressure by means of liquid pump 60 and pressurized liquid stream 14 is vaporized, such as by passage through main heat exchanger 70, to produce elevated pressure oxygen product gas stream 15. Generally, the elevated pressure oxygen product gas will have a pressure within the range of from 30 to 200 psia. Depending upon the heat exchanger design requirements, it may be preferred that the boiling of stream 14 against condensing stream 30 be carried out in a separate heat exchanger (not shown) located between liquid pump 60 and main heat exchanger 70.
Oxygen product fluid stream 15 is then combined with blast air portion 127 in the output line downstream of the point where the blast air is divided into blast air portion and feed air portion, i.e. a point downstream of the point where column feed is withdrawn from the output line, to form oxygen-enriched blast air 136 having an oxygen concentration within the range of from 21 to 40 mole percent. Stream 136 is heated in blast furnace stoves 140 to a temperature generally within the range of from 1500° to 2500° F. and resulting heated oxygen-enriched blast air 138 is passed on to blast furnace 144.
FIG. 2 illustrates another embodiment of the invention wherein oxygen product fluid used to enrich the blast air is withdrawn from column 300 as gas. In the embodiment illustrated in FIG. 2 sidestream 36 is not employed as there is no need to vaporize oxygen product fluid. The elements of this embodiment which are common with those of the embodiment illustrated in FIG. 1 will not be described again in detail.
Referring now to FIG. 2, oxygen product fluid is withdrawn as gas from column 300 in stream 11 warmed by passage through heat exchangers 71 and 70 to form stream 34, which is compressed by passage through compressor 234 to form pressurized oxygen product fluid stream 15, which is then further processed as described above. In this embodiment, if desired, some oxygen product fluid may be withdrawn from column 300 as liquid in stream 12, passed through valve 53 and recovered as oxygen product liquid in stream 35.
FIG. 3 illustrates another embodiment of the invention wherein the enriching fluid for the blast air is taken from the lower pressure column. In this embodiment the oxygen fluid produced in the lower portion of the lower pressure column is lower purity oxygen having an oxygen concentration within the range of from 60 to 99 mole percent, and the oxygen fluid produced in the side column is higher purity oxygen having an oxygen concentration which exceeds that of the lower purity oxygen and is within the range of from 90 to 99.9 mole percent. In this embodiment feed air portion 128 is further compressed by passage through compressor 130 to a pressure within the range of from 60 to 120 psia, and resulting further pressurized stream 129 is passed to cooler 26 and further processed as discussed above. In this embodiment, higher pressure column 100 may operate at a higher pressure than in the previously described embodiments. The elements of the embodiment illustrated in FIG. 3 which are common with those of one of the earlier described embodiments will not be described again in detail.
Referring now to FIG. 3, first lower purity oxygen stream 110 is passed from the lower portion of column 20 into the upper portion of side column 300 wherein it is separated by cryogenic rectification into higher purity oxygen and remaining vapor. Higher purity oxygen liquid is used to condense feed air portion 3 in bottom reboiler 350. At least some of the remaining vapor is passed from side column 300 into lower pressure column 200 in stream 113. Higher purity oxygen may be recovered from side column 300 as gas and/or liquid. Higher purity oxygen gas may be withdrawn from column 300 as stream 111, warmed by passage through heat exchangers 71 and 70 and recovered as stream 134. Higher purity oxygen liquid may be withdrawn from column 300 as stream 112, passed through valve 53 and recovered as stream 135.
Second lower purity oxygen, which is used as the enriching fluid for the blast air, is withdrawn from the lower portion of column 200 in stream 150 and warmed by passage through main heat exchanger 70. Resulting stream 151 is compressed in compressor 234 to a pressure within the range of from 30 to 200 psia to form pressurized enriching stream 152, which is analogous to stream 15 of the embodiments illustrated in FIGS. 1 and 2, and is further processed as therewith described.
Now, by the use of this invention, one may efficiently integrate a cryogenic air separation plant with a blast furnace system to produce oxygen-enriched blast air. Although the invention has been described in detail with reference to certain preferred embodiments, those skilled in the art will recognize that there are other embodiments of the invention within the spirit and the scope of the claims. | A system which integrates a cryogenic air separation plant with a blast furnace system enabling efficient oxygen enrichment of the blast air, and, if desired, production of additional higher purity oxygen. | 5 |
BACKGROUND OF THE INVENTION
This invention describes a process for the removal or reduction in concentration of acetylene and carbon monoxide from methane and ethane. These impurities are typically found in methane and ethane that is derived from synthetic sources but may also be found in natural gas or in other gas mixtures.
These organic oxidizable impurities can be removed or reduced in concentration by a wide variety of chemical or physical procedures. Physical procedures for removal from methane are represented by distillation and adsorption. Both methods are based on equilibrium processes which require multiple steps for each additional increment of impurity removal. In addition, the physical methods generally are operated under cryogenic conditions which are comparatively costly. As a consequence, physical methods of impurity separation are terminated at an economic barrier depending on the economic advantage of removing an additional increment of impurity or at the desired methane/ethane purity level which may be beyond the economic barrier. It is particularly costly to purify methane or ethane beyond the economic barrier.
An alternative to physical methods of impurity removal from methane is the use of catalytic reduction. In this process, excess hydrogen is mixed with the impure methane stream which is then fed to a catalytic reactor in which certain of these impurities, such as olefins, may be converted to methane. This procedure does not extract the value of the impurities but does reduce their concentration. However, hydrogen is a relatively expensive material and is not always conveniently available.
In many cases the impurity level of methane and/or ethane may not affect its use and in some cases it may even be beneficial. However, in certain cases, it is important that the purity level of the methane and/or ethane be extremely high and the complete absence of these impurities is preferred. To accomplish this control of the impurity concentration via the extant physical or chemical procedures would be complicated and expensive or both. Thus it can be seen that there is a need for a less expensive method which is capable of reducing the concentration of these impurities in methane and/or ethane to very low levels.
SUMMARY OF THE INVENTION
The present invention provides a method of purification of methane and/or ethane which is based on oxidation of the impurities in the methane and/or ethane. The oxidizing agent is oxygen and the process is conducted in a catalytic reactor operating in the temperature range of 200° to 375° C. Catalysts effective for this process contain silver as the active component.
The process consists of mixing a sufficient quantity of oxygen with the methane and/or ethane stream to permit combustion of the contaminants. This stream is then passed through a catalyst bed providing the required conditions of oxidation. The resulting products of the purification step are carbon dioxide and water. These may be removed via conventional processes or left in the methane and/or ethane stream as desired.
DETAILED DESCRIPTION OF THE INVENTION
When an impure methane and/or ethane stream containing oxygen and optionally an inert gas such as nitrogen is passed over a catalyst as described below, combustion occurs predominantly among the contaminants before methane and/or ethane combustion occurs. With the catalysts described herein, the combustion process is normally very efficient providing carbon dioxide and water as the sole products. Control of the reaction can be achieved by controlling the variables of oxygen concentration, reactor temperature, and flow rate. By proper adjustment of these parameters, the impurities can be removed with little effect on the methane and/or ethane concentration. If the oxygen concentration required for complete removal of the impurities is higher than the flammability limit of the mixture, then a multiple-step process may be conducted in which oxygen is added to the methane and/or ethane stream at a safe concentration in each step until the desired impurity level is reached.
It goes without saying that for economic reasons it would be preferred to remove all of the contaminants in a one-step process if that is possible. The process of the present invention can be performed in one step if the concentrations of the contaminants are such that the oxygen concentration required to oxidize them is below the flammability limit of the gas mixtures so that the purification can take place without fear of an explosion. The methane and/or ethane stream and the oxygen are led to a catalytic reactor wherein the reaction temperature is controlled within the range of 200° to 375° C. If the temperature is below 200° C., then the reactivity is insufficient and if the temperature is above 375° C., then too much methane and/or ethane is oxidized. The oxygen concentration should be maintained at a level higher than but close to the stoichiometric concentration required to oxidize the contaminants. Preferably, the oxygen concentration range is from 0.5% to 1% above the stoichiometric concentration because more oxygen provides no benefit and would bring the mix closer to the flammability limit.
The amount of time that the gas mixture is in contact with the catalyst is also an important variable. The contact time can be increased by increasing the size of the reactor. It can also be increased by slowing down the flow rate of the gases through the reactor. The contact time is generally measured in terms of space velocity in units of hour -1 . Thus, it is preferred that the space velocity be in the range from about 50 to about 1,000 hour -1 , preferably for the most practical operation 100 to about 500 hour -1 , if the reaction takes place at atmospheric pressure because it allows maximum use of the reactor. Higher flow rates can be used if the temperature is increased.
In situations where the concentration or type of the impurities requires an oxygen concentration which is above the flammability limit of the gas mixture, multiple oxidation steps are required. Preferably, for safety and economic reasons, two oxidations take place. In each oxidation step, the concentration of the oxygen is kept below the flammability limit to prevent explosive combustion.
A wide variety of silver-based catalysts can be used to advantage in the present invention. These catalysts generally comprise a silver salt deposited on a porous support material such as alumina, silica or other inert refractory material. The catalyst might also include promoters such as alkali metals and alkaline earth metals. Commercially existing ethylene oxide silver-based catalysts generally provide acceptable performance in this process. Catalysts of this type are described in U.S. Pat. No. 3,725,307, issued Apr. 3, 1973.
The process may be operated with inert gases such as nitrogen or argon in the methane and/or ethane stream. The combustion products of the oxidation reaction are carbon dioxide and water and may be removed by conventional purification techniques if their presence is not desired in the purified methane and/or ethane stream. For use in an ethylene oxide reactor, the presence of carbon dioxide or water in the methane and/or ethane stream should not be detrimental to the process as both components are normally present in the reactor. If oxygen is not totally consumed in the purification process, the unreacted oxygen may be used to supplement the oxygen feed to the reactor.
The process is particularly suited for the removal of acetylene and carbon monoxide from methane, ethane, and methane and ethane gas mixtures. Carbon monoxide may be present in methane or ethane which is derived from synthetic natural gas plants or from refineries. It, as well as acetylene, can be removed according to this process.
EXAMPLE I
Removal of Acetylene and Carbon Monoxide from Methane
Acetylene and carbon monoxide may be present in methane derived from an ethylene cracker. Both components should preferably be removed from the methane before it is used as ballast gas in an ethylene oxide reactor. Oxidative purification can be applied to the purification of the methane stream.
Complete combustion of acetylene to carbon dioxide and water requires 2.5 volumes of oxygen per volume of acetylene whereas complete combustion of carbon monoxide to carbon dioxide requires 0.5 volumes of oxygen per volume of carbon monoxide. For enhanced efficiency of contaminant removal, an excess of oxygen may be added to the methane stream with from 0.5 to 1% normally being adequate for optimum removal.
If the concentration of contaminants requires an oxygen concentration greater than the flammability limits of the gas mixture, then a multiple pass process should be conducted in which oxygen is mixed with the methane stream to a concentration below the flammability limit. This mixture is passed through the catalytic reactor in which combustion of some of the impurities occurs. The resulting partially purified methane stream is again admixed with oxygen at a concentration below the flammability limit and reacted for a second time. This process is repeated until the concentration of impurities is down to the desired level.
A methane stream containing acetylene, 1000 ppm, and carbon monoxide, 2000 ppm, is mixed with oxygen to give an oxygen concentration of 0.75%. The oxygenated methane stream is fed to a reactor at a space velocity of 200 per hour and in the temperature range of 230°-240° C. The acetylene and carbon monoxide concentration of the outlet stream is greatly reduced. | A method is disclosed for the purification of methane and/or ethane which comprises oxidizing acetylene and/or carbon monoxide in the gas with oxygen at 200° C. to 375° C. in the presence of a catalyst which contains silver as the active component. | 2 |
STATEMENT OF CONTINUING APPLICATIONS
This application is a continuation-in-part of application Ser. No. 08/539,233, filed Oct. 4, 1995, now U.S. Pat. No. 5,639,185, which is a continuation-in-part of application Ser. No. 08/182,971, filed Jan. 13, 1994, now U.S. Pat. No. 5,456,551.
BACKGROUND OF THE INVENTION
1. Invention Field
The present invention relates to underwater trenching systems, and more particularly to a self-guiding system for trenching water bottoms for the installation of a pipeline. The preferred embodiment of the present invention teaches a system which is configured to be mounted about the pipeline to be buried, and which further contemplates a uniquely configured, forward mounted trenching/drive mechanism incorporating a cutter wheel generally about the width of the desired trench, the mechanism configured to propel the system as well as trench the desired area. An alternative embodiment of the contemplates a frontal high pressure jet array in lieu of the cutter head.
The trenching/drive mechanism of the preferred embodiment of the present invention further includes a high pressure spray array mounted about the frontal cutter wheel area, and a suction/mud pump assembly to the rear of the cutter wheel. The high pressure spray array provides the dual purpose function of loosening the area to be, trenched, as well as cleaning and removing the trenched matter from the cutter wheel.
The present invention further includes first and second buoyancy chambers which are configured to be uniformly lowered to the lower periphery of the unit frame, to provide skids for utilization of the present system in shallow water.
Other features of the present invention which are taught, and which may be implimented, include G.P.S. (global positioning system) receiver/data transmission for precise monitoring of the system during operations, thruster propulsion, and bottom loading of pipe into the frame via hinged bottom rollers, which may be powered.
Another alternative embodiment of the present invention teaches the incorporation of a framed system similar to that as taught in the present invention, but without the trenching/drive mechanism, and with the addition of a pipe cutter mounted to the rear of the unit frame, for utilization of pipeline recovery and dismemberment operations.
GENERAL BACKGROUND DISCUSSION
While the prior art may have contemplated a variety of underwater trenching systems for utilization in conjunction with laying pipe and related operations, none are believed to have contemplated the combination trencher/drive system of the cutter mechanism contemplated by the present invention.
A list of prior patents which may be of interest is presented below:
______________________________________Patent No. Patentee(s) Issue Date______________________________________(Plough Trenchers):4992000 Doleshal 02/12/914980097 Lynch 01/22/914410297 Lynch 10/18/834245927 Wharton 01/20/814091629 Gunn et al 05/30/78(Cutter WheelTrenchers/Dredges):4416014 Satterwhite 09/26/784301606 Hofmeester 11/24/814329087 Satterwhite 05/11/824314414 Reynolds et al 02/09/824470720 Lennard 09/11/844149326 Rosa et aI 04/17/793023586 Morrison 03/06/620708583 Powell 09/09/020941050 Sykes 11/23/093605296 Dysart 09/20/711220197 Cowles 03/27/170814270 Burch 03/06/060737021 Roberts 08/25/030141752 Boschke 08/12/730171380 Hawley 12/21/18750158717 Kuhn 01/12/1875(Trenchers with LateralCutting Members):4280289 Bassompierre-Sewrin 06/28/814274760 Norman 06/23/814022028 Martin 05/10/774714378 Lincoln 12/22/874516880 Martin 05/14/854117689 Martin 01/03/784087981 Norman 05/09/784044566 Biberg 08/30/773995439 Hahlbrock 12/07/763887237 Norman 04/15/753670514 Breston et al 06/20/723583170 DeVries 06/08/71(Movable Bit Trencher):3978679 Lecomte 09/07/76(Fixed Propeller Trencher):3004392 Symmank 10/17/61______________________________________
The prior art contemplates various systems for trenching, including for the installation of pipelines, including the following general categories:
A. Plough Trenchers
B. Cutter Wheel Trenchers/Dredges
C. Trenchers with Lateral Cutter Members
D. Movable Bit Trenchers
E. Fixed Propeller Trenchers
The present, searched for invention, as described above, teaches a system for excavating a trench for the burial of a pipeline incorporating many components as set forth in the patents cited herein.
Referring to category "A", U.S. Pat. No. 4,992,000 teaches a trenching sled which includes forward jets for loosening the area, and a rearwardly directed suction means for removing the trenched material.
Referring to category "B". U.S. Pat. No. 4,301,606 issued 1981 to Netherlands Offshore Co. teaches a underwater trenching apparatus for pipelines utilizing a cutter wheel (15) and water jets (24) for loosening the trenched material and rearly situated suction (22) for removing said trenched material.
U.S. Pat. No. 4,374,760 in Category "C" teaches a "Self Propelled Underwater Trenching Apparatus." to Norman which teaches a drive system which may have some general pertinence to the anode jumper system of the present invention.
U.S. Pat. No. 4,280,289 teaches another trencher which utilizes lateral cutter members, claiming a means of manipulating the rollers to avoid obstacles.
As may be denoted by a review of the above, there have been several machines configured to dig a trench in the bottom of the water to bury pipe, cables, etc. However, unlike the prior art, the present invention has a unique cutter mechanism which provides propulsion or driving means during operation.
SUMMARY DISCUSSION OF THE INVENTION
The present invention overcomes these prior art problems by providing an underwater trenching system for laying pipe and related activities which is highly reliable, relatively economical and overall effective in a variety of environmental and operative conditions.
A believed persistent problem with prior art underwater pipeline trenchers is that the drive mechanism has been ineffective at best or inoperative at worst under many operative conditions, the prior art relying primarily upon powered rollers contacting the pipe to be laid, pulling the unit frame along as the independently operated cutting system removes the water bottom. It is asserted that such a system may be ineffective for propelling the system along under certain conditions, as such a system relies upon the frictional contact of the transport rollers with the pipeline, which may be coated with lubricants or a slippery plastic or other rust inhibiting coating.
Unlike the prior art, the present system teaches a combination cutting mechanism/drive mechanism for propelling the system along as it performs the trenching operation, pulling the unit frame as it trenches, and thereby preventing hang-ups.
The present invention further contemplates the utilization of high pressure suction for removing and dispersing the cut water bottom matter, and directing said pressurized matter from the rear of the unit frame, providing additional forward force to assist in the propulsion of the present system along during the trenching process.
The present invention is configured such that the pipe is positioned in the side of the machine. The bottom rollers are stationary on the machine making a solid foundation for the pipe rollers to fasten to. Only two rollers, one on the front and one on the back of the machine are adjustable. This is compared to the above indicated prior art machines, wherein all four rollers are moveable, and thereby tend to slip on the pipelines, causing damage to the coating.
The present invention, unlike the prior art, utilizes hydraulic powered screw jacks to apply pressure to the upper rollers for gripping the pipeline. The screw jacks may be controlled manually or via trip switches, which can be automatically situated to allow the loosening of the rollers for passage of pipe joints or the like through the rollers.
An alternative embodiment of the present invention, especially configured for utilization on water bottoms including sugar sand, light mud suspensions or the like, is also provided, contemplating a frame having front and rear ends, a top and a bottom, and a pipe passage formed therethrough enveloped by upper and lower rollers. The frontal portion of the frame includes forward emanating high pressure jets of water for trenching the water bottom, while the rear portion may include thrusters; alternatively, driven impellers or propellers may be provided affixed to first and second pontoon members, as will be further discussed. The thrusters, impellers, or propellers may be provided in pairs at opposing sides of the vessel, or in the case of pontoons, one on each pontoon, so as to allow one to maneuver, or steer the vessel, when desired, via selective powering of each of the thrusters, impellers, or propellers.
The alternative embodiment further contemplates a bottom entry system for the pipe, wherein the lower rollers are releasable at one end, and hingedly connected to the frame at the other end, so as to be manually or powered via hydraulic or other motor means from a pipe engaging, horizontal position to an open, generally vertical position, allowing passage of the pipe through the frame and up to or away from the upper rollers, for installation or de-installation of the frame about the pipeline, respectively.
Other options for the present invention include G.P.S. (global positioning satellite) navigational systems provided on the frame of the unit, to relay the position of the unit to the operating barge or other vessel.
In addition to having pipeline and cable installation capability, an alternative design is configured for removal of the pipeline as well.
It is thus an object of the present invention to provide an underwater trenching system which may be utilized in a variety of environmental and operative conditions.
It is another object of the present invention to provide an underwater trenching system which utilizes a cutting/propulsion mechanism for driving the unit frame along the pipeline.
It is still another object of the present invention to provide an underwater trenching system which does not rely upon powered traction rollers engaged to the pipeline for driving the system
It is another object of the present invention to provide an underwater trenching system which incorporates a buoyancy/pontoon system which may also be utilized as a sled/skid system in shallow water areas.
It is another object of the present invention to provide an underwater trenching system which includes bottom pipe entry means, propulsion via thrusters, propellers, or impellers or the like, G.P.S. position fixing, and a forward high pressure jet array, thereby providing a system which is suitable for trenching sugar sand, light suspension mud and other "soft" water bottoms.
These and other objects of the present invention will be further discussed in the detailed specification of the invention infra.
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 an isometric view of the preferred embodiment of the underwater trenching apparatus of the present invention.
FIG. 2 is a side view of underwater trenching apparatus of FIG. 1, illustrating the operation of the cutter/drive mechanism and jetting/dispersion of trenched material.
FIG. 3 is a frontal view of the underwater trenching apparatus of FIG. 1, illustrating the communication of the roller guide system with the pipeline, and positioning of the trench cutter mechanism and unit frame and ballast tanks.
FIG. 4 is a rear, close-up side, closed view of the reciprocating dispersion conduit of the suction array of the trenching apparatus of FIG. 1.
FIG. 5 is a side view of the reciprocating conduit of the suction array of FIG. 4, illustrating the reciprocating conduit in the open position to allow the pipeline to pass therethrough.
FIG. 6 is a side view of the underwater trenching apparatus of FIG. 1, illustrating the operative driving of the cutteridrive mechanism and jetting dispersion of the present system in operation.
FIG. 7 illustrates the operation of the rachet driven roller carriage to allow the passage of an exemplary pipe joint therethrough.
FIG. 8 illustrates the first and second exemplary pumps for providing high pressure spraying action for the spray array situated about the front end of the cutter mechanism.
FIG. 9 lilustrates a frontal view of the underwater trenching apparatus of FIG. 1, illustrating the positioning of the ballast tanks for use as skids in shallow water.
FIG. 10 is an isometric view of a removable shear module to be placed at the rear of the unit frame of the present invention when performing the alternate task of removin and cutting pipe from a buried pipeline.
FIG. 11 is a side view of an alternative embodiment of the present invention, illustrating a frame having high pressure jets provided at the forward end of the frame, a rear thruster for propulsion, G.P.S. position determination, and hinged lower rollers for bottom installation of the pipe through the frame.
FIG. 12 illustrates the alternative embodiment of FIG. 11, but with the implementation of propeller-driven pontoons as opposed to rear thrusters.
FIG. 13 illustrates the opening of the lower portion of the frame for the pipe, showing the lower rollers in their vertical position for passage of the pipe therethrough.
FIG. 14 and 14' illustrate an alternative embodiment of the invention of FIG. 11, illustrating powered lower rollers in closed and open positions, respectively.
FIG. 15 illustrates a side view of FIG. 14', providing a view of the power rollers in their open position.
DETAILED DESCRIPTION OF THE INVENTION
As can be seen in FIG. 1, the underwater trenching system of the preferred. exemplary embodiment of the present invention, includes a trenching apparatus T having a unit frame 2 having a lower 1 and upper end 3 with a medial area 6 therebetween, first 4 and second 5 sides, a front 13 and a rear 14.
As further illustrated, formed through the medial area 6 of the frame is a longitudinal opening forming a pipeline passage 7 passing through the front 13 and rear 14 sections of the frame, and surrounded on three sides by lower 8 and upper 9 support frames, communicating via the second side 5 of the frame. As shown, the first side 4 of the frame has a medial opening corresponding with the pipeline conduit 7, as will be more fully explained below.
As shown, affixed to the lower support frame 8 are forward 11A and rear 10B, longitudinally aligned rollers, while pivotally affixed to the upper support frame are forward 11A and rear 11B rollers, said rollers configured to, in conjunction with the lower rollers, envelope, grip and roll said unit frame 2 along a pipeline. Rollers 11A, 11B may further include drive/braking means, and are configured to pivotally adjust via screw jacks 31, 32, their detailed operation of which will be set forth infra.
Pivotally affixed to the lower 1 front 13 section of frame 2 is the cutterldriving mechanism, a "ditch digger", comprising a cutter housing 12 having an open front 18 and having situated about said open front's periphery a high pressure spray array 15 having a plurality of spray orifices emanating therefrom.
Situated within the front opening of said cutter housing is cutter wheel 19, having a width approximately that of the unit frame, and a further comprising a multitude of cutting members in axial alignment with said wheel, said wheel rotating about an axis generally transversal to the longitudinal axis of said unit frame. As will be further disclosed infra, debris trenched by said cutter wheel is directed via suction through said housing 12 and into a high pressure discharge conduit 16, where it is guided along the length of the unit frame, up lateral column 23 and out of the system via conduit 24.
Also removing trenched debris from the area are first 17 and second 20 lateral columns, configured to remove debris from the newly trenched bottom area via mud pumps 21, 22, respectively.
Providing buoyancy to the system are first 25 and second 26 pontoons, each spaced from the unit frame sides via first 27 and second 28 pivot arms, controlled by reciprocating pistons 29, 30, respectively.
As further shown, pistons 101 may be provided having first and second ends, the first end pivotally affixed to the front of the unit frame, the second affixed to the opposing 105, 104 sides of the cutter housing 12, for pivotally maneuvering said cutter housing. For example, retracting 102 piston 101 on side 104 of the cutter housing would urge the front of said housing generally toward 106 said piston 101, while extending 103 said piston would urge the front of said housing generally away from 107 said piston, effectively allowing the user to drive the present invention during the cutting operation. Load sensors 108 on either side of the cutter housing would allow an operator to monitor uneven pressures on the cutter housing, allowing monitoring of the progress of the system even in murky waters.
FIG. 2 illustrates a side view of the present invention in operation, cutting a trench T through the seabed S, installing a pipe P. As shown, in operation, the pipeline P is configured to pass through the pipeline passage via the opening (7) formed in the first side wall of the unit frame, as shown in FIG. 1. Referring to FIG. 4, the first 17 lateral column includes a lower end 36 having a lower suction opening 39 and upper end 37 having a mud pump 21 mounted thereon, and a discharge port.
Juxtaposed the upper and lower ends of the first lateral column is a medial area comprising a slidingly adjustable column 38 configured to slidingly migrate up U into the upper area of said lateral column via reciprocating piston 40, thereby providing an opening O for placement of the pipe P therethrough, as more fully shown in FIG. 5.
Returning to FIG. 2, once the pipeline is positioned within the conduit, the slidingly adjustable column 38 forming the medial area of the first lateral column 17 is lowered to communicate with the lower section, and the pipe P is positioned upon the fixed, lower rollers 10A, 10B. Lastly, the pivoting upper rollers 11A, 11B are lowered to frictionally engage pipe P via screw jacks 31, 32 engaging pivot support arms 43, 42 via threaded 46, 47 lateral adjustment shafts 44, 45, respectively. As shown, pivot support arms 41, 42 have rollers 11A, 11B connected to opposing first ends, and said second ends are connected to the medial area 43 of upper support frame 9.
As shown in FIGS. 2, 6, and 7, pivoting upper rollers 11A, 11B may have mounted thereon front 50 and rear 51 hydraulic motors and/or brakes, for assisting in driving the unit frame along the pipeline, or regulating same when the cutter wheel is in use. The rollers may be selectively raised and lowered 52, to allow the passage of anodes or the like therethrough, via the utilization of proximity switches 48, 49 to raise, and switches 48', 49' to lower the rollers via screw jacks 31, 32 respectively, selectively and automatically allowing the raising and lowering of the rollers 11A, 11B so that obstacles such anodes J, as shown in FIG. 6, may pass therethrough.
An alternative form of the present invention may utilize a single front and single rear proximity switch to raise and lower both the rollers 11A, 11B at the same time via their respective screw jacks 31, 32, to allow the passage of the anode or obstacle. This universal control for simultaneous raising and lowering of the rollers may be desirable where the independent operation of any one of the rollers without the other would mar or otherwise damage the protective coatings on the pipeline.
As shown, the cutter wheel housing tapers from a relatively wide, open area to a relatively narrow, rear area R, wherein said housing is pivotally connected to the lowver front portion of the unit frame via pivot point H which may comprise, for example, a ball hitch/socket arrangement.
Cutter wheel in cutter wheel housing 12 is driven via hydraulic motor which is supplied power via line 33 from the surface barge, and said cutter wheel housing 12 is controlled or steered via hydraulic pistons 34 mounted to each side of said housing, the underside of which is mounted to the lower portion of the unit frame, as shown in FIG. 6.
As shown in FIGS. 2, 6, 11, 12, and 13, the rear of the housing includes mud pump 35 are configured to provide suction to direct the trenched debris from said cutter wheel through the suction/discharge conduit 16, jettisoning via discharge conduit 24 situated at an angle dispersing the pressurized debris in an angled upward path 55 to the upper rear area of the unit frame, providing downward, forward propulsion on said frame, while directing the rear portion of said frame downward to allow the lower, suction openings 39 of the lateral conduits to communicate with the trench T bottom, wherein loose trench bottom is directed up said lateral conduits via mud motors 21, and out of discharge conduits 54, at a directly rearward discharge 54, providing additional forward propulsive force F. The cutter wheel revolves in a forwardly directed revolution 56 relative the unit frame, providing propulsive force forward in addition to cutting the water bottom to form a trench. FIG. 8 illustrates an exemplary series pump configuration for providing stepped, high pressure fluid for powering the spray array 15 formed about the periphery of the cutter wheel opening on the cutter wheel housing. As shown, sea water is taken in via suction opening 58 and pumped via first stage pump 59, through conduit 60 to second stage pump 61, prior to being directed to the array about the ditch digger 63 via hose 62.
FIG. 3 illustrates a front view of the present invention, illustrating the exemplary apparatus trenching a water bottom or seabed S. As shown, the cutter wheel 19 rotates in downwardly revolving, forward cutting and driving matter, with the spray array 15 configured to loosen and disperse trenched material, much of which is directed into the cutter wheel housing via the cutter wheel and suction therebehind.
As further shown in FIG. 3, the pontoons 26, 25 are at their upper position, held in place via pivot arms 27, 27", respectively, providing balanced buoyancy support to the system.
FIG. 9 illustrates an alternative position of the pontoons 26, 25 in the present invention, to allow said pontoons to perform as skids along the seabed S in shallow water where there is insufficient water depth to provide the desired buoyancy, or where a trench shallower than the height of said cutter wheel is desired. As shown, the reciprocating pistons 29', 29" have been extended to drive the pivot arms 27', 27" downward D, until said pontoons 26, 25, communicate with the seabottom S, supporting the unit frame and cutter wheel.
POWER SOURCE #1
The main power source of the present invention comes from the compulsion force of the three eight inch hydraulic driven pumps. Two of the pumps (21, 22) are mounted on the rear of the machine and the other one is on the Ditch Digger (35) and discharging from the rear of the machine, powering the machine forward.
The two pumps on the rear of the machine serve three purposes:
1. They pump the mud out of the ditch which the pipe will be buried in;
2. The compulsion force drives the machine forward; and
3. By regulating the speed of each pump individually, one can control the direction in which the machine travels.
POWER SOURCE #2
The Ditch Digger or cutter wheel (19) is powered by a hydraulic motor and gear reduction drive, which will serve two purposes:
1. The teeth of the Ditch Digger are arranged in such a manner as to cut the bottom (being mud) into small pieces
2. The eight inch pump (35) mounted on the rear of the cutter wheel will discharge the mud to the rear of the machine while forcing the machine forward. The teeth are grabbing and cutting the bottom causing this forward movement of the machine.
POWER SOURCE #3
The pipe is held on place by four rollers which may be the traditional hourglass shape, or may be somewhat grooved to fit the contour of the pipe. The two bottom rollers (10A,B) are mounted in a stationary position. The two top rollers (11A,B)are in a frame pivoted on one end controlled on the other each by hydraulic screw jacks (31, 32). Each screw jack applies force to the frame of the roller, in turn, the rollers hold the pipe in place in the frame of the machine. The rollers are also used as a power source to drive the machine forward or backward. They are powered by a hydraulic motor(50,51) on each roller.
When the machine comes to an obstacle on the pipeline, an air-over hydraulic or electric switch will cause the top, rear and front rollers to come off the pipeline until the obstacle passes through the machine, then an air-over hydraulic or electric switch mounted on the rear of the machine will reverse the direction at the hydraulic screw jacks to apply pressure once again on the pipeline. The screw jacks can be electro-mechanical or hydro-mechanical, as desired.
When the rollers are in the raised position, the machine is powered forward by compulsion force of the three eight inch hydraulic powered pumps and the Ditch Digger located in front of the machine, continuously digging the bottom and pulling the machine forward.
PONTOONS
The Underwater Ditch Digger has two pontoons (25, 26), one mounted on each side of the machine. They are adjustable to allow the machine to bury pipe in water depths from three feet.
The pontoons hold the machine in a vertical position when burying pipe. There are high pressure volume tanks built inside each pontoon to store air so that the water can be blown out of the bottom of each pontoon when the machine needs to be made lighter. A valve on top can be opened to let the air out and water in, to give it to more weight.
There are two hydraulic cylinders per pontoon. The cylinders are closed and the pontoons are in a vertical position for deep water. For shallow water the pontoons are in a ninety degree position, with the machine and the cylinders extended out.
The Ditch Digger cuts a ditch at a minimum of thirty inches deep, the height of the cutter wheel and spray array, in one pass. It pulls the machine forward as it is cutting the ditch. It has a jetting pipe or spray array (15) mounted around the housing of the cutter with nozzles. Two hydraulic cylinders (34) push the Ditch Digger down for a deeper ditch. It has an eight inch pump (35) mounted on the back end of the cutter housing (12) to pump the mud out and is also used for compulsion force to help move the machine forward. The blades are made of a material similar to the road grader blades material. The cutting blades are mounted inside a funnel to catch the mud. In doing this the eight inch suction pump will be able to pump it out to the rear of the machine.
JET PUMP
There is a high pressure water pump, or series of two pumps as shown in FIG. 8 driven by hydraulic motor, mounted on the machine, supplying high pressure water to the jet nozzles, which are mounted on a pipe around the Ditch Digger. This high pressure water helps soften the bottom and therefore makes it easier for the Ditch Digger to chop up mud, debris, etc.
FRAME
The unit frame (2) may be made out of square tubing and is designed so the pipe is placed in the machine from the side. It is designed to withstand the pressures put on it by the forward thrust of the pumps, the screw jacks applying pressure downward on the top rollers, the pontoons upward lifting and also the forward pulling of the Ditch Digger. It is designed to hold three mud pumps, a jet pump and the pontoons. The pipe burying equipment is removable so the frame can be used as a pipe retriever and by adding a hydraulic shear (FIG. 10) on the rear of the machine also cut up the salvage pipe into desired length. By removing the shear it can be used as a devise to lay pipelines.
HOSE REEL
A hose reel may be utilized in the present system, said reel designed to accommodate the bundle of hydraulic hoses going from the hose reel to the Ditch Digger allowing for three hundred to six hundred feet of extra hose. The shaft is drilled and grooved in such a manner that each pressure and return hose has its own port. The drum rotates on the shaft, which is stationary, the drum is powered by a hydraulic motor and chain drive with sprockets. The stand that the hose reel is housed is mounted on a barge or boat and enables an operation to let out or take up the hose as desired without disconnecting the hoses from the reel.
HYDRAULIC HOSES
The hydraulic hoses or power lines are strapped together in a bundle. There are approximately twenty hoses going to the machine. The pressure hoses are three thousand PSI hoses, and a two hundred fifty PSI air hose. The hoses have hydraulic quick disconnect on either end and are made up from three hundred to six hundred feet in length, the hoses are fastened to the hose reel on one end and the Ditch Digger machine on the other end.
CONTROL PANEL
The control panel is located upon a surface vessel, and has gauges and flow meters so an operator can monitor the machine at all times. There are directional valves to operate the machine, which one controls how fast the machine moves on the pipeline, how fast the Ditch Digger is turning, the amount of jet pressure, the mud pumps, the cylinder on the Ditch Digger to determine the depth of the ditch, the pontoons and the screw jacks, etc. The control panel may be connected to the hose reel with hydraulic disconnects on one end and the other to the power unit. The control panel is mounted on the deck of a barge of boat.
ANODE JUMPER
The anode jumper may consist of two toggle switches mounted on the machine, one on the front and one on the rear. The toggle switches are hooked to an air-over hydraulic or electrical directional valve that controls the direction. The hydraulic or electrical screw jack turns, either raising or lowering the rollers on the pipe. When the machine comes in contact with an anode, the screwjack will raise the rollers and let the anode pass through the machine, then lower the rollers back into position on the pipe, as this process is taking place, the mud pumps and the Ditch Digger propel the machine forward. By using this method, one set of rollers are not trying to power the machine forward by itself, which could spin on the slick pipe and damage the coating on the pipeline.
SCREW JACKS
The powered screw jacks are mounted in a vertical position over the frame in which the rollers are housed in. The frame is hinged on one end with pillow-block bearings, the rollers being on the opposite end. The screw jack powers the rollers up and down on the pipe with a pre-set amount of pressure. This pressure on the rollers hold the pipe in place in the frame and also keep the rollers from spinning on the pipe while the rollers are being used to force the machine forward. The screw jacks are controlled by the anode jumper switches and also by the operator on the barge when the pipeline is being placed in the machine.
An advantage of using screw jacks is that they will not loosen up on the pipeline (verses the hydraulic cylinder) until they are powered by hydraulic pressure, either from the anode jumper on the machine or the operator on the barge.
POWER UNIT
The power unit may consist of a diesel engine driving four or more hydraulic pumps. The diesel engine is compatible to a twelve cylinder Detroit engine. The pumps are mounted in a series on the rear of the engine. There is a volume tank for the hydraulic oil, a manifold to distribute the oil to the desired working positions, pressure setting and relief valves to set the desired pressure for each working component of the machine. The unit is built on-skid and is mounted on a barge or boat and supplies power through the control panel to the machine.
PONTOON CYLINDERS
There are two pontoons (25, 26), one on either side of the machine, each having two hydraulic cylinders. The hydraulic cylinders are attached from the frame of the machine to two arms extended to the pontoons. The arms will rotate the pontoons from ninety degrees of the machine to one hundred eighty degrees of the machine. Tthe hydraulic cylinders work independently in pairs, two for each pontoon, therefore one pontoon can be ninety degrees of the machine and the other one hundred eighty degrees with the machine. This enables the machine to stay in a vertical position when there is a cross current, when the pontoons are both extended to ninety degrees with the machine, it enables pipe to be buried in water as shallow as three feet.
SUCTION PIPES OR LATERAL COLUMN MUD LIFTS
There are two suction pipes or lateral column (17, 20) mud lifts on the rear of the machine, in a vertical position, extending from the bottom of the frame to above the frame, the frame being made into three sections: top, middle, and bottom. One of the suction pipes is made in three sections. A section mounted to the bottom and top sections of the frame, the center section of the suction pipe is grooved on each end for two "O" rings. The center section fits inside the top section and is powered downward to fit inside the bottom section of the suction pipe, forming a sealed fit on both ends of the center suction pipe. This forms a continuous length of pipe.
The hydraulic driven mud pumps are mounted on top of the suction pipes, with a discharge pipe (which is smaller) pointed to the rear and outward of the machine. This giving the machine a compulsion force forward and discharges the mud and debris out of the ditch. The two discharge pipes (54)are ninety degrees to the suction pipes. The third discharge pipe (24) comes from the rear of the Ditch Digger to the top rear of the machine and discharges the mud and debris to the rear and outward of the machine also causing a compulsion to push the machine forward.
DITCH DIGGER OR CUTTER WHEEL (19)
The Ditch Digger is the apparatus used on the machine to cut a ditch in the bottom of a body of water so that a pipeline can be buried or cable, etc. it is powered by a hydraulic motor and gear reduction drive by chain or shaft. The Ditch Digger blades are housed in a funnel opened on the forward end and an eight inch suction pump on the other. The pump serves two purposes: (1) To suck the mud and debris that the blades cut and extract them to the rear of the machine which causes also a compulsion force to help power the machine forward, (2) The blades have shaft through the center, a sprocket is positioned in the middle of the shaft, which is connected to the gear drive. The blades are made in two sections allowing a gap of approximately two inches between them for the driving chain or shaft. The chain has a coin guard built around it with seals in the shaft to keep the mud off the chain and sprockets. The blades are attached to the funnel by self sealed flange bearing, also there are two hydraulic cylinders attached to the funnel from the frame to dig a deeper ditch. The cylinders are extended and the funnel rotates on a shaft on the bottom rear of the funnel and is exerted downward to the required depth of the ditch being dug.
METHOD OF RETRIEVING AND LAYING PIPE
Remove the Ditch Digging equipment from the machine and mount the hydraulic shear (FIG. 11) on the rear of the machine. The four rollers grooved to the pipe size, guides and pulls the pipe off the bottom onto the barge or boat. It travels through the machine and the shear cuts the pipe to the desired length. The cut-off pieces fall into a rack mounted over a pan. The pan catches any oil spilled. When the desired amount is cut, it is banded up and ready for shipment to be disposed of.
This method eliminates spilled oil or gas out of the pipelines into the water and also fire from cutting the pipes with a torch.
By removing the dredging equipment and the hydraulic shear the machine becomes a tension device for laying pipelines.
Two machines can be used at one time. One used as a tension shoe, the other used to bury the pipe as it is being laid. Now two jobs can be done in the time it used to take to do one. Also, the job of retrieving and salvaging old abandoned pipelines is cleaner and safer, using the Ditch Digger, for the environment and for the men working on the project.
The invention embodiments herein described are done so in detail for exemplary purposes only, and may be subject to many different variations in design, structure, application and operation methodology. Thus, the detailed disclosures therein should be interpreted in an illustrative, exemplary manner, and not in a limited sense.
ALTERNATIVE EMBODIMENTS OF THE INVENTION
Referring to FIGS. 11-13, an alternative embodiment of the present invention, especially configured for utilization on water bottoms including sugar sand, light mud suspensions or the like, is also provided, contemplating a frame 201 having front 202 and rear 203 ends, a top 204 and a bottom 205, and a pipe passage 206 formed therethrough enveloped by upper and lower 207, 208 rollers. The frontal portion of the frame includes a forwardly emanating high pressure jet array 209 powered by a high pressure pump via hose 210, projecting water for trenching the water bottom, while the rear portion may include rearwardly emanating thrusters 210. The bottom of the frame is open, having no cross-members situated under the lower roller area, to allow the passage of pipe longitudinally through the frame via the bottom of the frame.
Other options for the present invention include a G.P.S. (global positioning satellite) navigational system 211 provided on the frame of the unit, configured to relay the position of the unit to the operating barge or other vessel via wire, sonar, or RF transmission or the like.
Referring to FIG. 12, alternatively, driven impellers or propellers 212 may be provided affixed to first 25 and second pontoon members, to provide controlled, steerable forward or rear propulsion of the system. The thrusters, impellers, or propellers may be provided in pairs at opposing sides of the vessel, or in the case of pontoons, one on eaci pontoon, so as to allow one to maneuver, or steer the unit, when desired, via selective? powering of each of the thrusters, impellers, or propellers. Thusly, the unit may be able to be controlled to some degree without communication with the pipe, such as in situations at the beginning or end of a pipeline, or installation or de-installation of the unit to commence or complete trenching operations.
As shown, the lower rollers have first and second ends which are supported by a roller frame having first and second ends, forming first and second roller support members, respectively. Each of the roller support members are hingedly attached to the frame at one end 213, 214, and releasably attached at the opposing end, via releasable bracket or the like, as shown in FIG. 13.
Continuing with FIG. 13, the roller support members 217, 218 are shown in a generally vertical, open position, so as to allow the passage of pipe P therethrough, the roller support member each having first and second ends, the first end hingedly connected 213, 214 to a side of the frame at one end, and supported by said hinged end when the opposing end is detached. Once opened, the frame may then be lowered 219, effecting installation of the frame about the frame, or raised 220, removing the frame from the pipe.
The hinged movement of the roller support members may be provided manually, via SCUBA divers or the like, or pneumatically, via motors or the like, as will be more fully discussed. Upon the positioning of the first and second roller support members in their generally horizontal, support, closed positions, the brackets at their respective second ends engage the frame at the opposing side of the first end, and the rollers thereby generally envelope the lower portion of the pipe P.
FIGS. 14, 14' illustrate a powered positioning system for positioning the roller support members in their generally closed, horizontal position 221 for closed rollers about the pipe, or the open, generally vertical position 222, providing an open passage for removal of the pipe, wherein the lower rollers are releasable at one end, and hingedly connected to the frame at the other end, end like the above embodiment of FIGS. 11-13, and further powered via hydraulic or other motor means from a pipe engaging, horizontal position to an open, generally vertical position, allowing passage of the pipe through the frame and up to or away from the upper rollers, for installation or de-installation of the frame about the pipeline, respectively.
Referring to FIG. 15, the alternative embodiment of FIGS. 14, 14' contemplate first and second roller support members 223, 224, respectively having first 225, 225' and second 226, 226' ends, the first 225, 225' ends hingedly attached to one side of the frame, the second ends 226, 226' releasably attached to the opposing side of the frame, via brackets 228, 228' or the like. Motors 227, 227' communicate with roller support members 223, 224 to effectuate remote pivoting of the roller support members about their respective hinged ends, while actuators 229, 229' may be provided to latch and unlatch brackets 228, 228' in place. | A self-guided system for trenching water bottoms for the installation of a pipeline. The preferred embodiment of the present invention teaches a system which is configured to be mounted about the pipeline to be buried, and which further contemplates a uniquely configured, forward mounted trenching/drive mechanism incorporating a cutter wheel generally about the width of the desired trench, the mechanism configured to propel the system as well as trench the desired area. An alternative embodiment of the contemplates a frontal high pressure jet array in lieu of the cutter head. The trenching/drive mechanism of the preferred embodiment of the present invention further includes a high pressure spray array mounted about the frontal cutter wheel area, and a suction/mud pump assembly to the rear of the cutter wheel. The high pressure spray array provides the dual purpose function of loosening the area to be trenched, as well as cleaning and removing the trenched matter from the cutter wheel. The present invention further includes first and second buoyancy chambers which are configured to be uniformly lowered to the lower periphery of the unit frame, to provide skids for utilization of the present system in shallow water. An alternative embodiment of the present invention teaches the incorporation of a framed system similar to that as taught in the present invention, but without the trenching/drive mechanism, and with the addition of a pipe cutter mounted to the rear of the unit frame, for utilization of pipeline recovery and dismemberment operations. Other features of the present invention which are taught, and which may be implemented, include G.P.S. (global positioning system) receiver/data transmission for precise monitoring of the system during operations, thruster propulsion, and bottom loading of pipe into the frame via hinged bottom rollers, which may be powered. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a foaming nozzle to be mounted in a sprayer such as a trigger sprayer. This sprayer is known as a spin sprayer having a spray nozzle for swirling a liquid at a high speed to inject a mist for fungusproofing a joint between tiles laid in a bath room or cleaning a window glass. A foaming nozzle is mounted in the spray nozzle of the spin sprayer so that a fungusproofing detergent may be injected in a foamed state by squeezing the sprayer.
2. Description of the Prior Art
In Japanese Utility Model Laid-open No. 69579/1988, for example, there is disclosed a trigger sprayer. If a foaming nozzle is mounted in the spin spray nozzle of the trigger sprayer and the trigger of the sprayer is squeezed, the mist cluster spin-injected from the spray nozzle impinges upon the inner wall face of the mouth of the foaming nozzle and is mixed with the ambient air and foamed so that a foam cluster is injected from the foaming nozzle mouth.
The foaming nozzle of the prior art is formed into the shape of a true circle cylinder so that the mist cluster injected through the spin passage of the trigger sprayer by squeezing the sprayer has its outer circumferential portion impinging upon the inner face of the foaming nozzle and is foamed until it is injected in the shape of a circular foam cluster. In the trigger sprayer, moreover, the amount of mist to be injected by the single triggering action is substantially fixed so that the foam cluster is injected in a crowd.
The foam cluster usually raises no trouble even if its shape is circular. In case, however, the fungusproofing detergent is to be sprayed along the initially white joints of tiles laid in a bath room, the range of the joints to be covered with the foam can be made wider if the foam is elongated along a joint than if the same is circular. In case, on the other hand, the detergent is to be sprayed on a window glass, the circular foam cluster would overflow and ooze the surrounding, if it is sprayed directly to the corners of the window glass. Thus, the foam cluster is desired to have angular portions. On the other hand, the foam cluster of the prior art is defective in that it will crowd to have a relatively small coverage.
The present invention contemplates to eliminate such defects and enables the foam cluster to be highly diverged by considering the positional relation between the spray nozzle and the foaming nozzle, to be formed into the shape of a transversely elongated band or an ellipse by forming the foaming nozzle into the shape of an elliptical cylinder, and to be injected in a rectangular or triangular shape by forming the foaming nozzle into the shape of a rectangular or triangular cylinder, so that the band-, rectangle- and triangle-shaped foams can be freely selectively injected together with the round foam of the prior art.
SUMMARY OF THE INVENTION
According to the present invention, a foaming nozzle having the shape of an elliptical cylinder is so fitted in the front of a spray nozzle for spin injection that a portion of the mist passing through said foaming nozzle may entrain and diffuse the foam, which is caused in the foaming nozzle, and may be injected in a mist-foam mixed cluster having a cross-section of a transversely elongated band shape. With this structure, it is possible to widen the spray range when a fungusproofing detergent is to be sprayed to the joints between tiles.
According to the present invention, moreover, baffle plates are protruded in the directions to oppose each other from the middle portions of the shorter-diameter peripheral wall portions of the foaming nozzle having the shape of the elliptical cylinder so that the mist-foam mixed cluster injected from the foaming nozzle may be formed into the shape of the transversely elongated band to have higher densities at the two end portions of the band-shaped portion and lower density at the middle portion. This shaping makes it convenient to spray the detergent or the like to the two parallel joints between the tiles and to the intervening tiles, for example.
According to the present invention, moreover, a partition plate for halving a nozzle port is extended between the middle portions of the shorter-diameter peripheral wall portions of the foaming nozzle having the shape of the elliptical cylinder so that the mist-foam mixed cluster injected from the foaming nozzle may be sprayed in two separated smaller circular clusters to the target face. This shaping makes it convenient to spray the aforementioned two parallel joints or the like.
According to the present invention, moreover, arcuate recesses for moving the mist-impinging portion to the front end of the foaming nozzle are formed in the front end face of the shorter-diameter peripheral wall portions of the elliptical cylinder. This shaping makes it possible to spray the aforementioned mist-foam mixed cluster with the elliptical sectional shape effectively to not only the aforementioned joints but also the corners of the window glass.
According to the present invention, moreover, a plurality of grooves for uniformly scattering the mist and foam in the nozzle are formed in the inner face of the shorter-diameter peripheral wall portions of the elliptical cylinder. This shaping makes it possible to scatter the mist and foam all over without being locally deviated.
According to the present invention, the foaming nozzle having the shape of a square cylinder is so fitted in the front of the aforementioned spray nozzle that a part of the mist passing through the foaming nozzle may entrain and diffuse the foam caused in said nozzle until it is injected in a mist-foam mixed cluster having a square section. This shaping makes it possible to spray the detergent to apply the angular portions of the mist-foam mixed cluster to the corners of the window glass, for example, thereby to avoid the wetting of the window frame with the mist-foam mixed cluster.
According to the present invention, moreover, arcuate recesses for moving the mist-impinged portion to the front end of the foaming nozzle having the aforementioned shape of the square cylinder are formed in the front end face of the foaming nozzle. This shaping makes it possible to enlarge the divergence of the mist-foam mixed cluster having the square section.
According to the present invention, moreover, the aforementioned foaming nozzle is formed to have the shape of a rectangular cylinder, and arcuate recesses are formed in the shorter-diameter side wall portions. This shaping makes it possible to form a mist-foam mixed cluster having the rectangular section thereby to convert the aforementioned spray of the joints conveniently into the spray of the window glass corners by making use of the angular portions.
According to the present invention, arcuate recesses are formed in the individual sides at the front end of a triangular cylinder in the front of the aforementioned spray nozzle. This shaping makes it possible to form a mist-foam mixed cluster having a triangular section and makes it convenient to spray the window glass corners or the like by making use of the angular portions.
According to the present invention, moreover, the aforementioned triangular cylinder is a regular triangular cylinder, and the arcuate recesses are formed in the individual sides of the front end of the triangular cylinder. This shaping makes it possible to form a mist-foam mixed cluster having the section of a regular triangle and makes it convenient to spray the window glass corners by making use of the angular portions.
According to the present invention, moreover, the foaming nozzle to be mounted in the front of the aforementioned spray nozzle is composed of a first foaming nozzle and a second foaming nozzle hinged to rise or fall to the front portion of said first foaming nozzle. Moreover, the first foaming nozzle is formed into the shape of an elliptical, rectangular or triangular cylinder, and the second foaming nozzle is formed into the shape of a true circular cylinder. The sectional shape of the mist-foam mixed cluster to be injected by the action of the sprayer with the aforementioned foaming nozzle is formed either into an ellipse other than the true circle by injecting it directly from the first foaming nozzle or into a foam cluster having the section of a true circle by attaching the second foaming nozzle so that the sectional shape of the mist-foam mixed cluster can be freely changed. Specifically, the injection liquid can be changed, in dependence upon the shape or the like of an object, into a mist-foam mixed group or a foam cluster. Moreover, the sectional shape of the mist-foam mixed cluster, i.e., the spray shape of the mist-foam mixed cluster on the sprayed surface can be changed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a section showing a trigger type sprayer nozzle portion, in which a foaming nozzle having the shape of an elliptical cylinder of the present invention is mounted;
FIG. 2A is a section showing the foaming nozzle shown in FIG. 1,
FIG. 2B is a front elevation of the same;
FIG. 3A is a section showing a foaming nozzle having the shape of an elliptical cylinder according to another embodiment and taken in the direction of the longer diameter;
FIG. 3B is a front elevation of the same;
FIG. 3C is a section taken in the direction of the shorter diameter;
FIG. 4A is a section showing a foaming nozzle having the shape of an elliptical cylinder according to another embodiment and taken in the direction of the longer diameter;
FIG. 4B is a front elevation of the same;
FIG. 4C is a section taken in the direction of the shorter diameter;
FIG. 5A is a section showing a foaming nozzle having the shape of an elliptical cylinder according to another embodiment and taken in the direction of the longer diameter;
FIG. 5B is a front elevation of the same;
FIG. 5C is a section taken in the direction of the shorter diameter;
FIG. 6A is a section showing a foaming nozzle having the shape of an elliptical cylinder according to another embodiment and taken in the direction of the longer diameter;
FIG. 6B is a front elevation of the same;
FIG. 6C is a section taken in the direction of the shorter diameter;
FIG. 7A is a section showing a foaming nozzle having the shape of an elliptical cylinder according to another embodiment and taken in the direction of the longer diameter;
FIG. 7B is a front elevation of the same;
FIG. 7C is a section taken along line C--C of FIG. 7A;
FIG. 8 is a section showing a trigger type sprayer mouth portion, in which a foaming nozzle having the shape of a square cylinder of another embodiment is mounted;
FIG. 9 is a front elevation showing the sprayer mouth portion;
FIG. 10 is a diagram for explaining the operation of the foaming nozzle mounted in the same sprayer;
FIG. 11 is a section showing a trigger type sprayer mouth portion, in which a foaming nozzle having the shape of a square cylinder of another embodiment is mounted;
FIG. 12 is a diagram for explaining the operation of the foaming nozzle mounted in the same sprayer mouth portion;
FIG. 13 is a diagram for explaining a foam cluster injected from the foaming nozzle;
FIG. 14 is a perspective view showing a foaming nozzle having the shape of a rectangular cylinder according to another embodiment;
FIG. 15 is a diagram for explaining the operations of the same foaming nozzle;
FIG. 16 is a diagram for explaining the operations of the same foaming nozzle;
FIG. 17 is a section showing a trigger type sprayer mouth portion, in which a foaming nozzle having the shape of a triangular cylinder of another embodiment is mounted;
FIG. 18 is a front elevation showing the same sprayer mouth portion;
FIG. 19 is a diagram for explaining the operation of the foaming nozzle mounted in the same sprayer;
FIG. 20 is a section showing a trigger type sprayer mouth portion, in which a foaming nozzle having the shape of an isosceles triangular cylinder of another embodiment is mounted;
FIG. 21 is a front elevation showing the same sprayer mouth portion;
FIG. 22 is a diagram for explaining a mist-foam mixed cluster injected from the same foaming nozzle;
FIG. 23 is a side elevation of the same foaming nozzle;
FIG. 24 is a front elevation showing the same foaming nozzle;
FIGS. 25A, 25B and 25C are diagrams for explaining the impinging ranges of the mist cluster upon the inner faces of the individual portions of the front end of the same foaming nozzle;
FIGS. 26A and 26B are sections showing the same foaming nozzle;
FIG. 27 is a section showing the state, in which a second foaming nozzle is mounted in the mouth portion of the trigger sprayer having the foaming nozzle of the embodiment of FIG. 7 mounted therein; and
FIG. 28 is a section showing the state, in which the same second foaming nozzle is raised.
In FIG. 29 showing the relations between the mist clusters spin-injected from the injection nozzle port and the foaming nozzle:
FIG. 29A is a diagram for explaining the portion in which a denser ring-shaped mist portion does not impinge upon the inner face of the foaming nozzle;
FIG. 29B is a diagram for explaining the portion in which only the outer peripheral portion of the same ring-shaped mist portion impinges; and
FIG. 29C is a diagram for explaining the portion in which the same ring-shaped mist portion impinges in its entirety.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will be described in more detail with reference to the accompanying drawings.
First of all, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. Reference numeral 1 designates a spray nozzle for a trigger type sprayer. This spray nozzle 1 is fitted in the front portion of a liquid injection tube 2 of the trigger type sprayer, for example. The injection tube 2 has its front end formed with a well-known spin passage 3, and a spray port 4 is so bored in the center of the front end face of the spray nozzle 1 as to communicate with the passage 3. From the outer circumference of the front end face of the spray nozzle 1, there is protruded forward a cylinder 5 for fitting a foaming nozzle member 6 therein.
This foaming nozzle member 6 has a rectangular base 7 to be fitted in the cylinder 5. The rectangular base 7 is formed in its central portion with an elliptical hole elongated to the right and left, from the peripheral edge of which is protruded forward a foaming nozzle 8 having the shape of an elliptical cylinder. The base 7 is further formed with air vent holes 9 and 9 above and below the nozzle 8. From the outer periphery of the base 7, on the other hand, there is protruded backward a clearance forming cylinder 11 for giving the air vent holes 9 and 9 and a foaming nozzle port 10 the communication with the spray port 4 at the back of the foaming nozzle member 6. The foaming nozzle and the spray nozzle 1 are disposed on a common axis. On the other hand, a denser ring-shaped mist portion 32 surrounding a mist cluster, which is spin-injected in the shape of a hollow cone from the spray port 4 by the squeezing action of the sprayer, is caused to wholly impinge upon the inner faces of shorter-diameter peripheral wall portions 8a and 8a positioned at the two shorter-diameter sides of the foaming nozzle 8, as shown in FIG. 29C. The denser ring-shaped mist portion 32 is also caused to pass substantially in its entirety over longer diameter peripheral wall portions 8b and 8b positioned at the two longer-diameter sides, as shown in FIG. 29A, without any impingement.
in the shown embodiment, the foaming nozzle port 10 has the longer diameter of 9 mm, the shorter diameter of 3.5 mm and a length of 4 mm.
With the structure thus made, the liquid is caused to pass through the well-known spin passage 3 formed inside of the spray port 4 so that it is injected forward while swirling at a high speed, if the spray nozzle 1 is directed forward and squeezed. Most of the mist droplets atomized by the high-speed swirls draw a helical locus while having their diameters enlarged the more by the centrifugal force resulting from the swirls as they leave the spray port the more. As a result, the mist cluster 31 formed of all the mist droplets is injected generally in the shape of a hollow cone at a constant injection angle. In other words, the mist cluster 31 is injected in the sectional shape of such a circle by the action of the aforementioned centrifugal force that the outer circumference is the denser ring-shaped mist portion 32 whereas the inside surrounded by the outer circumference is a thinner mist portion.
As described above, the denser ring-shaped mist portion 32 impinges in its entirety on the inner faces of the shorter-diameter peripheral wall portions 8a and 8a, as shown in FIG. 29C, but not at the longer-diameter peripheral wall portions 8b and 8b, as shown in FIG. 29A. As a result, the mist portion 32 has its outer peripheral portion impinging but its inner peripheral portion not, as shown in FIG. 29B, between the two end portions of the shorter-diameter peripheral wall portions and the longer-diameter peripheral wall portions 8b and 8b. At the time of the injection, the foam caused as the result of impingement is mixed with the mist, which is to pass as it is, into a mist-foam mixed cluster 35. The mixed cluster is injected in the sectional shape of a band, as shown in FIG. 1, since it takes the widest injection angle in the case of FIG. 29A, as indicated by blanked arrows 40, and the narrowest injection angle in the case of FIG. 29C. In this case, moreover, the band-shaped sectional portion may have more foam at its two end portions but less foam at the middle. The reason for this phenomenon could be explained in the following manner although not clearly. The injection velocity is decelerated by the foaming, which is caused by the impingement of the denser ring-shaped mist portion 32 at a more backward inner faces of the peripheral wall portions than the case of FIG. 29C, so that the mist will be entrained by the mist portion which is scattered at a high speed over the longer-diameter peripheral wall portions.
In a second embodiment, as shown in FIG. 3, a pair of baffle plates 13 are formed to protrude short in directions to oppose each other from the upper and lower middle portions of the shorter-diameter peripheral wall portions at the front end face of the foaming nozzle having the shape of an elliptical cylinder. If this foaming nozzle is mounted like the first embodiment and is subjected to the injection, the middle portion becomes further thinner with the two end portions being denser than the case of FIG. 2A.
In a third embodiment shown in FIG. 4, a partition plate 14 is extended at a middle between the shorter-diameter peripheral wall portions of the foaming nozzle having the shape of an elliptical cylinder so as to halve the nozzle port 10. With this structure, the mist-foam mixed cluster injected from the nozzle port 10 can be injected in two circular clusters 36 and 36 spaced at the righthand and lefthand sides, as shown in FIG. 4A.
In a fourth embodiment shown in FIG. 5, arcuate recesses 15 are formed in the front faces of the shorter-diameter peripheral wall portions at the front end of the foaming nozzle 8 having the shape of an elliptical cylinder so as to cause the denser ring-shaped mist portion 32 to impinge substantially in its entirety upon the front portion of the nozzle port at the longitudinal middle portions of the shorter-diameter peripheral wall portions 8a and 8a and to have a less impinging range 33 as the ends of these shorter-diameter peripheral wall portions are approached. At the same time, the ring-shaped mist portion 32 is allowed to pass without any impingement over the longer-diameter peripheral wall portions 8b and 8b. In this case, as shown in FIG. 5A, the mist-foam mixed cluster 35 to be injected has the shape of a transversely elongated generally elliptical shape. Incidentally, in case of the present embodiment, a more ring-shaped mist portion 32 does not impinge directly upon the inner face of the foaming nozzle port 10 so that the mist-foam mixed cluster to be injected from the foaming nozzle port 10 has its injection angle increased and is largely diverged.
In a fifth embodiment shown in FIG. 6, arcuate protrusions 16 are formed at the front end of the foaming nozzle shorter-diameter peripheral wall portions 8a having the shape of an elliptical cylinder so that the ring-shaped mist portion 32 may pass closely over the longer-diameter peripheral wall portions 8b. At the inner faces of the shorter-diameter peripheral wall portions 8a, therefore, the foam cluster is extruded along the inner faces of the protrusions 16 even after the mist portion 32 has impinged upon the inner faces of the shorter-diameter peripheral wall portions 8a and has been foamed. Moreover, the foam cluster is entrained by the ring-shaped mist scattered at a high speed toward the longer-diameter peripheral wall portions, so that the mist-foam mixed cluster 35 is injected in the shape of a cocoon, as shown in FIG. 6A.
in a sixth embodiment shown in FIG. 7, a plurality of grooves 17 are so formed in the inner faces of the foaming nozzle shorter-diameter peripheral wall portions 8a having the shape of an elliptical cylinder that they are radially dispersed forward from the back. The mist-foam mixed cluster 35 injected in the shape of a band, as shown in FIG. 7A, are dispersed by those grooves 17 into denser mist-foam mixed clusters 35a spaced generally at an equal distance.
The front end faces of the shorter-diameter peripheral wall portions 8a are formed into the arcuate recesses 15 but may be formed into the shape of a plane normal to the axis, as in the embodiment of FIGS. 1 and 2. In the shown embodiment, the grooves 17 are extended from the rear end of the foaming nozzle to just the front of the middle but not to the front portion. This is to facilitate the extraction and machining of the molding die when the foaming nozzle is integrally molded of a synthetic resin. For this, the inner face portion of the foaming nozzle to be formed with the grooves is tapered to have a reduced diameter rear end.
in a seventh embodiment shown in FIGS. 8 to 10, the foaming nozzle 8 is formed into the shape of a square cylinder. A cylinder 6b with the foaming nozzle 8 has its two front and rear end faces opened, and four support members 6a are equidistantly protruded from the inner face of the rear portion and connected to the individual corners of the outer face of the foaming nozzle 8. The inner face of the cylindrical wall of the foaming nozzle 8 may be formed with spray guide members 17a in place of the aforementioned grooves. The foaming nozzle 8 is so positioned that the denser ring-shaped mist portion 32 may impinge in its entirety upon the middles of the individual sides of the foaming nozzle having the shape of the square cylinder and may be foamed, as shown in FIG. 29C. At the corners of the front end of the foaming nozzle, on the other hand, the mist portion 32 is caused to pass without any impingement, as shown in FIG. 29A. As a result, the mist portion 32 is partially foamed while the remainder is allowed to pass between the middles of the individual sides and the corners of the front end of the foaming nozzles, as shown in FIG. 29B. As has been described, the aforementioned mist and foam are mixed into their mixed cluster 35, which has the shape of a square 38 circumscribed by a true circle 37 having the section of the extension of the outer circumference of the denser ring-shaped mist portion 32.
In case the foaming nozzle 8 is given the shape of a square cylinder, the arcuate recesses 15 are desirably formed between the two ends of the front faces of the individual sides of the square formed by the front end face of the foaming nozzle, as shown in FIGS. 11 to 13. By forming the impinging range 33 elongated along the arcuate recesses, the foaming can be effected all over the inner face of the mouth without any deviation, so that the mist and foam can be dispersed substantially uniformly, as shown in FIG. 13.
In an embodiment shown in FIGS. 14 to 16, the foaming nozzle 8 is formed into the shape of a rectangular cylinder. In this case, the arcuate recesses 15 are formed in the front faces of the longer sides of the rectangular cylinder so that the denser ring-shaped portion 32 of the mist cluster 31 injected through the foaming nozzle 8 may impinge more on the inner faces of the arcuate recesses 15 and less on the inner faces of the shorter sides but may pass closely over the front end portions of the four corners. In case of the foaming nozzle having the rectangular cylinder shape, the mist cluster impinging range 33 at the longer side, as shown in FIG. 16, is far longer than that at the shorter side, as shown in FIG. 15. This is because the distance from the spray port 4 is so different that the mist cluster 31 injected in the shape of a hollow cone having a denser ring-shaped mist portion impinges at its outer circumference upon the longer sides in an earlier stage in which the cluster has a small-diameter section, and upon the shorter sides at a later stage in which it has a larger-diameter section.
In an embodiment shown in FIGS. 17 to 19, the foaming nozzle 8 is formed into the shape of an equilateral triangle cylinder. In case of this embodiment, too, the cylinder 6b with the foaming nozzle 8 is fitted in the cylindrical portion 5 of the spray nozzle 1. The cylinder 6b is a cylinder having its front and rear end faces opened, and the foaming nozzle 8 is connected coaxially to the cylinder 6b by the three support members 6a protruded at an equal spacing from the inner face of the rear portion of the cylinder 6b. As shown, the spray guide members 17a may be formed on the inner face of the cylindrical wall portion defining the inner face of the foaming nozzle.
In case of the present embodiment having the mouth shaped in the equilateral triangle, as shown in FIG. 19, the arcuate recesses 15 of a common size are formed between the two ends of the individual sides with the most depression at the middle of each side. Most of the denser ring-shaped mist portion 32 impinges upon the middle portions of the individual sides, and its impinging range 33 is reduced the more the two ends of the individual sides are approached, until its outer side closely passes at the two ends of the individual sides, i.e., at the front ends of the corners of the triangular mouth, as shown in FIG. 29A.
In an embodiment shown in FIGS. 20 to 26, the foaming nozzle 8 is formed into the shape of a right angle triangle cylinder. In case of this embodiment, as different from the case of the equilateral triangle cylinder, the distances from the center of the inscribed circle 39 of the right angle triangle to an acute angle portion 18 and to a right angle portion 19 are different, and the distances from that center to the middle of the two sides containing the right angle and to the middle of the remaining side are different. In the structure in which the center of the inscribed circle 39 is positioned on the extension of the center axis of the spray port 4, therefore, the mist cluster 31 injected in the shape of the hollow cone from the spray port 4 has its outer circumference impinging at first upon the portion, in which the inscribed circle and the individual sides contact, and then radially enlarged so that the impinging range 33 is circumferentially extended to reach the front end of the inner face of the right angle portion 19 and further the front end of the inner face of the acute angle portion 18 as the outer circumference is moved forward.
Mist-foam mixed cluster 35 is formed by causing the spin-injected mist cluster to impinge upon the inner face of the mouth. In order that the sectional shape of the mist-foam mixed cluster 35 may be formed into the section of a right angle triangle and gradually enlarged, the denser ring-shaped mist portion passing without impingement has to be minimized at the mouth portion which is first hit by the outer circumference of the mist cluster 31, and the denser ring-shaped mist portion passing without impingement has to be maximized at the mouth portion which is hit the latest. Moreover, the outer side of the mixed cluster 35 of the foam or the like caused by the impingement has to be corrected in the scattering direction so that its section may have the shape of the right angle triangle as a whole and that its triangle may be gradually enlarged. For this, as shown in FIG. 23, the right angle portion 19 is made shorter than the acute angle portion 18 to form the arcuate recesses 15 in the front end portions of the individual sides. Incidentally, the acute angle portion 18 is so formed that the denser ring-shaped mist portion of the mist cluster 31 has its outer face come close to but passes angle portion 18 without any impingement.
FIG. 25 shows the ratio of the amount of the denser ring-shaped mist portion of the mist cluster that impinged upon the individual portions of the inner face of the mouth of the foaming nozzle 8, and the amount of the same that was scattered without any impingement. FIGS. 25A and 25B show the acute angle portion 18 and the right angle portion 19 of the foaming nozzle, respectively. FIG. 25C shows such a portion of each side, in which the inscribed circle 39 and the inner edge of each side contact, as shown, that the mist cluster impinges on the inner face of the mouth at the earliest stage. The blanked arrows 40 indicate the corrected injection direction of the outer side of the mixed cluster 35 of the foam or the like caused as a result of the impingement. In the case of FIG. 25A, the foam already caused at the portions of FIGS. 25C and 25B are scattered and mixed, as the mist comes closer to the front end of the acute angle portion 18 as the front end of the foaming nozzle 8, so that the denser ring-shaped mist portion has its density reduced and is injected as the mist-foam mixed cluster 35 from the mouth. FIGS. 26A and 26B show the impingement range 33 of the mist cluster on the inner face of the foaming nozzle mouth.
The regular triangle cylinder and the rectangular equilateral triangle cylinder are exemplified as the desired shape of the foaming nozzle of a triangular cylinder but can naturally be exemplified by another triangular cylinder. In this modification, arcuate recesses according to the individual sides of the mouth have to be formed in the front end faces of the side portions in accordance with the case of the rectangular equilateral triangular cylinder.
Since the mist injection angles of the mist clusters of the aforementioned individual embodiments are determined depending upon many conditions including the number of swirls of the spray pressure spin and the length and diameter of the spray port, the sprayer for mounting the foaming nozzle has to be equally sized. For fine adjustment of tills spray angle, moreover, the spray nozzle 1 may desirably be screwed in the injection tube 2, or the foaming nozzle member 6 may desirably be screwed in the spray nozzle 1 so that the spray nozzle 1 may be adjusted with respect to the injection tube or so that the aforementioned member 6 may be adjusted with respect to the spray nozzle.
In an embodiment shown in FIG. 27, the cylinder 5 having the foaming nozzle member 6 fitted therein has its upper portion notched, and a second foaming nozzle 20 formed with a nozzle hole having the cross-section of a true circle has its rear portion fitted in the front portion of the cylinder 5. The second foaming nozzle 20 has its rear portion which is so hinged to the cylinder 5 in the aforementioned notch portion, that said second foaming nozzle can be freely raised or fallen. In this embodiment, the first foaming nozzle 8 owned by the foaming nozzle member 6 and the second foaming nozzle 20 constitute together a foaming nozzle structure. The first foaming nozzle is formed into the shape having an elliptical cylinder so that the mist-foam mixed cluster 35 having the cross-sectional shape of an ellipse or band injected from the first foaming nozzle can be changed, if necessary, into a foam cluster having the cross-section of a true circle by mounting the aforementioned second foaming nozzle 20. In other words, the injected liquid can be freely changed into a foam cluster of a true circle or into a mist-foam mixed cluster of an ellipse or band by mounting or demounting the second foaming nozzle. The first foaming nozzle 8 of this embodiment is exemplified by the foaming nozzle having its inner face formed with the grooves 17, as shown in FIG. 7, but may be exemplified by the square or triangle foaming nozzles of the remaining embodiments. Incidentally, the cylinder 5 and the second foaming nozzle 20 are formed with retaining holes 21 and projections 22 for retaining the position of the second foaming nozzle when this nozzle is turned and fallen upward. Incidentally, an output cylinder 23 in the shown embodiment, is protruded in the shape of a double cylinder from the back of the second foaming nozzle.
To the front end portion of the spin spray nozzle of a sprayer, according to the present invention, there is so fitted coaxially with the spray nozzle a foaming nozzle having the shape of an elliptical, rectangular or triangular cylinder that the denser ring-shaped mist portion in the outer circumference of the mist cluster spin-injected in the shape of a hollow cone from the spray port 4 is partially refrained from impinging upon the inner face of the foaming nozzle whereas the remaining ring-shaped mist portion impinges upon the inner face of the foaming nozzle and is foamed until the foam and a portion of the mist are mixed and injected. As a result, depending upon the shape of the foaming nozzle, the mist-foam mixed cluster can be injected in the shape of a band, ellipse, rectangle or triangle so that it can be efficiently sprayed on a joint between tiles or a corner of a window glass. As has been described above, moreover, the denser ring-shaped mist portion is partially caused to pass as it is without impinging upon the inner face of the foaming nozzle and is mixed during the passage with the foam caused on the nozzle inner face so that the mist-foam mixed cluster is prepared. As a result, the mixed cluster can have its injection angle enlarged to extend the range of the area to be sprayed. If, moreover, the foaming nozzle is formed of the first foaming nozzle 8 having the shape of a non-circular section and the second foaming nozzle 20 having the section of a true circular section and if the second foaming nozzle 20 is removably attached to the first foaming nozzle 8, the injection liquid can be advantageously injected in the foam cluster having the sectional shape of a true circle or in the mist-foam mixed cluster having another shape such as a transversely elongated band, if necessary. | A foaming nozzle mounted in front of a spray nozzle of a sprayer so that a liquid detergent may be sprayed in a foamed state onto a window glass or tile for cleaning. The foaming nozzle has its mouth shaped so that a mixed cluster of the mist and foam from the foaming nozzle is injected in a band, elliptical, rectangular or triangular shape and at a wide angle. A predetermined relationship between a spray port and the foaming nozzle allows the mist spin-injected at a high swirling speed to be partially mixed with the foam. The foam is formed by the impingement of the mist upon an inner face of the mouth of the foaming nozzle. The mixture may be injected at a wide angle. The foaming nozzle can be composed of first and second nozzles wherein the second foaming nozzle is of a circular cylinder and hingedly mounted to the first foaming cylinder. The user can selectively inject either a mist-foam mixed cluster having the band section or a foam cluster having a circular section. | 1 |
TECHNICAL FIELD
The present patent application for industrial invention relates to an anchoring system of counterweights for washers and washer/dryer combos.
BACKGROUND
The peculiarities and advantages of the present invention will be more evident after a short description of the state-of-the-art.
With reference to FIG. 1 , the current models of washers and washer/dryer combos are provided with a plastic tub with composite structure, being formed of two separate parts ( 1 , 2 ) designed to be securely coupled by means of fixing means of known type.
The first part consists in a large concave cylindrical body ( 1 ) closed at one end by a bottom wall ( 10 ) with a central hole, connected on the back with a cylindrical nozzle ( 11 ) designed to exactly receive a metal bearing support with basically cylindrical shape.
The second part consists in a flange ( 2 ) provided with a large central opening ( 20 a ) designed to be mounted at the front open end of the concave cylindrical body ( 1 ).
Such a tub usually contains a cylindrical drum ( 3 ) designed to be loaded with dirty laundry through the opening ( 20 a ) of the front closing flange ( 2 ) of the tub.
The drum ( 3 ) is closed on the back by a bottom wall ( 30 ) with an axially protruding shaft ( 31 ) in central position, designed to be driven into rotation by the electrical motor that is normally mounted in the household appliance outside the tub.
In particular, the shaft ( 31 ) is designed to be inserted and supported, with the interposition of a pair of ball bearings with different diameter, inside the bearing support inserted in the nozzle ( 11 ) on the bottom wall ( 10 ) of the concave cylindrical body ( 1 ) of the tub.
The shaft ( 31 ) of the drum ( 3 ) is driven into rotation by a motor fixed in external position on the tub.
Moreover, such a traditional tub is fixed inside the cabinet of the washer by means of suitable elastic means, which are also designed to act as shock absorbers for the significant mechanical stress transmitted to the tub during the rotations of the drum, especially during spinning.
The presence of the elastic elements avoids the damages caused by the high stress to the structure of the tub.
The aforementioned tub-assembly is traditionally identified as “Oscillating Assembly”.
The tendency of the laundry loaded inside the drum ( 3 ) to be arranged in a totally random way during the rotation of the drum ( 3 ) originates an unbalanced rotational mass associated with a centrifugal force that can reach very high values.
To counterbalance the centrifugal force and avoid the contact with the cabinet, the oscillating assembly must be ballasted up to a total weight normally ranging between 32 and 60 kg.
To reach such a weight counterweights (normally two, sometimes one or three) usually made of concrete must be anchored to the tub.
With reference to FIG. 2 , to favour the anchoring and centring of the said counterweights ( 21 ), the cylindrical body ( 1 ), as well as the corresponding front flange ( 2 ), is externally provided with one or more cylindrical columns ( 22 ), each of them being internally provided with an axial rectilinear conduit ( 22 a ) designed to receive a corresponding self-tapping screw ( 24 ).
As shown in FIG. 2 , each column ( 22 ) protrudes from a corresponding enlarged base with cylindrical shape ( 23 ).
Each counterweight ( 21 ) is provided with a through hole ( 21 a ), with basically truncated-conical shape, designed to receive one of the said columns ( 22 ) when the counterweight is engaged against the upper side of the corresponding enlarged base ( 23 ).
In this way the upper end of each column ( 22 ) can be accessed from the upper opening of the hole ( 21 a ) of the counterweight ( 21 ) to allow for engagement with the self-tapping screw ( 24 ).
The self-tapping screw ( 24 ) is generally provided with a large washer ( 26 ) designed to be energetically engaged around the upper opening of the hole ( 21 a ) of the counterweight ( 21 ).
The careful examination of a similar prior technique has shown critical aspects that can be remedied by the present invention.
A first severe limitation of the said traditional columns ( 22 ) relates to the operation principle.
Reference is made to the fact that the mutual coupling between the column ( 22 ) and the hole ( 21 a ) of the counterweight ( 21 ) is obtained because of the compression and permanent deformation of the plastic material of the column ( 22 ).
More precisely, the said deformation is produced in the upper end of the enlarged base ( 23 ) of each column ( 22 ) because of the energetic interference produced by the lower opening of the hole ( 21 a ) of the counterweight ( 21 ) following to the progressive tightening of the screw for mutual fixing ( 24 ).
In fact, due to the tightening of the screw, the plastic material of the base ( 23 ) of the column ( 22 )—being generally reinforced or loaded polypropylene material—tends to be moulded and forcedly adhered against the surface of the counterweight ( 21 ).
In this condition the anchoring of the counterweight is not completely satisfactory, since the counterweight may be moved from its operational position without control.
Such a case could occur, for example, in case of anomaly of the electronic system that controls the rotation of the said drum with the laundry.
In case of such an anomaly, the inertial force generated on the oscillating assembly of the washer may be so high that it cannot be efficaciously opposed by the front interference established between the plastic material of the base ( 23 ) and the concrete material of the counterweight ( 21 ).
Moreover, the traditional columns ( 22 ) have a very complex geometry that requires the use of a large quantity of plastic material as well as long cooling time at the end of the moulding operations.
In view of the above, the parts of the tub provided with the said columns (reference is made to the cylindrical body and corresponding closing flange) cannot be extracted from the corresponding moulds, although perfectly cooled, until the longer cooling process of the columns has been completed.
Because of the said cooling difficulties, undesired unexpected internal cavities may be formed on the structure of the columns, thus impairing the resistance and correct fixing with the counterweights.
In the worst cases the presence of the said internal cavities totally impairs the capability of a column to guarantee the anchoring of a corresponding counterweight because the self-tapping screw engaged inside it cannot reach the expected torque and loses its thread.
SUMMARY
The purpose of the present invention is to devise an anchoring system for counterweights that renounces the use of the traditional columns that cooperate with corresponding self-tapping screws, in favour of corresponding tubular cylindrical pins made of plastic material, which are provided with intrinsic elastic deformability because of the presence of longitudinal notches.
Like traditional columns, also the deformable pins are incorporated in external position on the tub of a washer or a washer/dryer combo during the moulding of the tub, being designed to be inserted from down up inside the holes of the corresponding counterweights, in such a way that their end can be accessed from the upper opening of the same holes.
Moreover, it must be said that the holes of the counterweights are provided with truncated-conical shape with the end with lower cross-section facing the centre of the tub.
Once each pin is inserted into the hole of the corresponding counterweight, a suitable elastic insert (a sort of plug) with truncated-conical shape must be inserted inside it.
Considering that each pin is provided with longitudinal notches, it is evident that the forced engagement of the corresponding insert inside it causes elastic divarication that determines its truncated-conical shape.
In this way the external walls of the pin can be energetically compressed against the internal walls of the truncated-conical hole obtained in the corresponding counterweight.
The considerable divaricating force exerted by the elastic insert on the walls of a similar tubular pin, in combination with the truncated-conical shape of the hole of the counterweight, guarantees that the pin remains firmly locked in operational position, without the possibility to be accidentally removed from the hole or move inside it.
The higher reliability, in terms of anchoring of the counterweights, provided by the new divaricable pins compared to the traditional columns is due to the fact that, following to deformation, the section of the pins perfectly matches the truncated-conical shape of the hole of the counterweight, in such a way that a very large contact surface is established between the plastic is material of the pin and the concrete material of the counterweight, thus guaranteeing mutual stable anchoring also in extreme conditions and for long periods of time (in practical terms, for the entire operational life of the household appliance).
Moreover, it must be said that the use of the said divaricable pins in external position on a tub for washers or washer/dryer combos also involves other advantages both from the merely technical-functional and the economic viewpoint.
First of all, it must be noted that each pin has a less sophisticated leaner structure than traditional columns, being provided with lower thickness comparable with the thickness of the parts of the tub (cylindrical body and corresponding perforated closing flange) from which they protrude.
In view of the above, it appears evident that the use of a low thickness allows for reducing the total weight of a tub for washer, as well as reducing the quantity of plastic material to be used and the costs for design and construction of moulds for the two traditional parts of a tub for washers.
Additionally, because of the low thickness, the pins are characterised by rapid cooling after the completion of the moulding process of the two parts of the tub for washers where they are to be incorporated.
This prevents the risk for the structure of each tubular element to be affected by undesired microcavities and, moreover, it allows for considerably reducing the waiting time before extracting the cylindrical body and the perforated flange of a tub from the corresponding moulds.
BRIEF DESCRIPTION OF THE DRAWINGS
For purposes of clarity, the description of the invention continues with reference to the enclosed drawings, which are intended for purposes of illustration only and not in a limiting sense, wherein:
FIG. 1 is a perspective view of a plastic tub in conventional models of washers and washer/dryer combos;
FIG. 2 is an enlarged view showing a structure used in conventional models of washers and washer/dryer combos for anchoring and centering of counterweights;
FIG. 3 is an axonometric view of a tubular divaricable element with relevant divaricating insert in non-operational position;
FIG. 3A is a cross-section of FIG. 3 with a vertical plane;
FIG. 3B is the same as FIG. 3A , except for the divaricating insert in operational position;
FIGS. 4 , 4 A and 4 B correspond to the three aforementioned figures, except for they refer to an alternative embodiment of the tubular divaricable element;
FIGS. 5 , 5 A and 5 B correspond to FIGS. 3 , 4 A and 3 B, except they refer to an additional alternative embodiment of the tubular divaricable element.
DETAILED DESCRIPTION
With reference to FIGS. 3 , 3 A and 3 B, the new system used to anchor concrete counterweight in external position on a plastic moulded tub for washers is based on the presence of a series of cylindrical divaricable pins ( 40 ) obtained from the same material and during the same moulding process as the two traditional parts of the tub, that it to say the traditional cylindrical body ( 1 ) and the corresponding front closing flange ( 2 ).
Each pin ( 40 ), which is provided with a regularly spaced set of three longitudinal notches ( 40 a ), is designed to be inserted from down up into the hole ( 21 a ) of a counterweight ( 21 ) when the counterweight ( 21 ) is arranged against the external wall of the tub.
In particular, it must be noted that the hole ( 21 a ) of the counterweight ( 21 ) has a truncated-conical shape with the end with lower cross-section facing the centre of the tub.
Following to penetration inside the hole ( 21 a ), the pin ( 40 ) is given such a position that the free end can be accessed from the upper opening of the hole ( 21 a ), as shown in FIGS. 3A and 3B .
Now, a corresponding cylindrical truncated-conical insert ( 40 b ), which is practically a sort of plug provided with a short sharp point, is inserted exactly inside each pin ( 40 ).
With reference to FIG. 3B , the forced insertion of the insert ( 40 b ) generates a divarication of the pin ( 40 ) favoured by the presence of the said longitudinal notches ( 40 a ), in such a way that the pin ( 40 ) is given a truncated-conical shape that perfectly matches and strictly adheres to the shape of the hole ( 21 a ) of the counterweight ( 21 ).
The mutual perfect interference between the external walls of the tubular element made of plastic material ( 40 ) and the internal walls of the hole ( 21 a ) of the counterweight ( 21 ) guarantees mutual stable resistant coupling, thus providing the stable safe anchoring of the entire counterweight ( 21 ) to the tub of the washer.
To further stabilise the coupling of the divaricating insert ( 40 b ) inside the central cavity of the pin ( 40 ), the insert ( 40 b ) is provided towards the top with a perimeter retention tooth ( 40 c ) designed to create friction against the internal walls of the pin ( 40 ).
FIGS. 4 , 4 A and 4 B refer to a second embodiment of the said divaricable pin ( 41 ) that, while adopting the same structural and functional configuration, is characterised by the fact that it is designed to be coupled in “screw” configuration with the corresponding divaricating insert ( 41 b ) with truncated-conical shape.
To that purpose, the internal walls of the pin ( 41 ) and the external walls of the insert ( 41 b ) respectively incorporate corresponding threads (F, F 1 ).
In such a situation, the operator in charge of fixing the counterweight ( 21 ) in external position on the tub of a washer will screw the divaricated insert ( 41 b ) until the desired pressure against the internal walls of the hole ( 21 a ) of the counterweight ( 21 ) is obtained on the divaricable walls of the pin ( 41 ).
FIGS. 5 , 5 A and 5 B refer to a third embodiment of the divaricable pin ( 42 ) that is identical to the embodiment shown in FIGS. 4 , 4 A and 4 B and consequently provided with longitudinal notches ( 42 a ).
The peculiarity of the said embodiment of the pin ( 42 ) refers to the fact that it is provided with a divaricating insert consisting in a helical spring with truncated-conical shape ( 42 b ) designed to penetrate forcedly into the corresponding tubular element ( 42 ) to cause the usual divarication.
In this case, a thread compatible with the turns of the said helical spring ( 42 b ) can be realised on the internal walls of the pin ( 42 ) in order to additionally stabilise the operational position of the spring ( 42 b ) inside the said pin. | The present invention relates to an anchoring system of counterweights for washers and washer/dryer combos based on the presence of a plurality of tubular divaricable pins ( 40, 41,42 ) on the external walls of the plastic molded tubs ( 1 ) that, after being inserted into through holes ( 21 a ) obtained on the said counterweights, are designed to receive suitable divaricating inserts ( 40 b, 41 b, 42 b ) to prevent uncoupling from the holes. | 3 |
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates to a method for coating a creased appearance on fabric. More particularly the present invention relates to a method for forming vintage effect washer by blowing up by air on one to another synthetic fiber filament yarns of a fabric, dyeing and drying the fabric with the filament yarns blown up as described in the above, getting the synthetic fiber partially back to the condition prior to the blowing-up of the synthetic fiber, thereby naturally producing a creased appearance, and the present invention also relates to the vintage effect washer manufactured according to the method described in the above.
[0002] Recently, in both the East and the West, the vintage fashion is getting popular among youth. The vintage fashion means second-hand clothes such as trousers with the cloth-edge being worn out and the stitching having come undone, shirts pock-marked with holes, discolored clothes worn for long, etc., and/or it is defined as a trend or tendency showing that people enjoy wearing second hand clothes as such. Lately, clothes with numerous rumpled creases formed on such as old clothes are also included in the vintage fashion.
[0003] However, different from a natural fiber, a synthetic fiber is crease-resistant, and the reality is that the clothes made of synthetic fiber can hardly meet the demand arising from the vintage fashion.
SUMMARY OF THE INVENTION
[0004] Today the vintage fashion has been brought into fashion among some youths, the likes or dislikes of the vintage fashion being out of the question. Accordingly its demand has been steadily increased. In the meantime, the recent spread of the well-being trend has caused the demand for the natural fiber also to increase steadily. Nonetheless, the demand for the fiber is met mostly by the synthetic fiber, because of the high price and insufficient supply for the natural fiber. However, because the synthetic fiber is crease-resistant, it is very difficult to form creases on clothes made of synthetic fiber. Therefore, it is desirable to develop a method for forming creases on the clothes made of synthetic fiber.
[0005] The present invention is intended to solve the technical problem described in the above and enable to form on synthetic fiber creases tantamount to creases on natural fiber first by blowing up by air on one to another synthetic fiber filament yarns of a fabric, dyeing and drying the fabric with the filament yarns blown up, forming creases naturally on the synthetic fiber, that is, clothing fabric, and using the fabric to make clothes.
BRIEF DESCRIPTION OF THE DRAWING
[0006] The FIG. 1 illustrates a flow chart showing a process for forming creases on synthetic fiber.
DESCRIPTION OF THE MAJOR PARTS OF THE DRAWING
[0007]
[0000]
100
Fabric
110
Roll
200
Crease-forming Device
210
Air Nozzle
300
Crease-fixing Device
400
Dyeing Machine
410
Roll
420
Dyeing Liquid
500
Drying Machine
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0008] The present invention is described in detail as follows:
[0009] The FIG. 1 illustrates a flow chart showing a process for forming creases on synthetic fiber.
[0010] The synthetic fiber used in the present invention is polyester. And several sizes are available for the thickness of a filament, but it is desirable to use 50, 65 and 75 denier fibers, which are used most in the clothing manufacture.
[0011] The present invention is described in detail with reference to the drawing as follows:
[0012] The first step is to prepare a sufficient length of fabric ( 100 ) to convolve the roll ( 110 ). Normally a shipment is made for the unit of 50 m. However, taking into consideration that the fabric should go through a series of works, such as the crease-forming device ( 200 ) through the crease-fixing device ( 300 ) and the dying machine ( 400 ), where dying requires a plurality of circulation, to the drying machine ( 500 ), it is necessary to convolve the roll ( 110 ) with a sufficient length (e.g. 1000 m) of fabric ( 100 ), two or more units of fabric being connected. Various ways of connecting fabric to fabric such as sewing are available.
[0013] Subsequently, the fabric ( 100 ) convolved around the roll ( 110 ) is delivered to the crease-forming device ( 200 ). The interior temperature of the crease-forming device ( 200 ) ranges 70 to 90° C. and a plurality of the air nozzles ( 210 ) are installed inside the crease-forming device ( 200 ). A filament assembly of a synthetic fiber is composed of dozen filament yarns. And when air blows up hard on the fabric ( 100 ) delivered to the crease-forming device ( 200 ) for two to four hours, the spaces between the filaments yarns composing the filament widen, the filament yarns become twisted, and, as a result, a creased appearance is formed. The fabric ( 100 ) that has gone through the crease-forming device ( 200 ), being compared with the original fabric ( 100 ), becomes wider by 20 to 30%.
[0014] Further, the crease-formed fabric ( 100 ) with the spaces between the filament yarns widened as described in the above is delivered to the crease-fixing device ( 300 ), and heated under 90 to 100° C. for three to five hours, then the creases formed on the fabric are fabricated, that is, the creases embody the fabric ( 100 ), thereby, the creases are fixed, and not dissolved in the subsequent processing.
[0015] Further on, the fabric ( 100 ) with the creases formed as described in the above is delivered to the dying machine ( 400 ), and dyed for a color tone as desired. The dying machine ( 400 ) is of a kind that is used normally in the industry. And inside are installed a plurality of rolls ( 400 ) which are convolved by the fabric, and in the lower part is contained the dyeing liquid ( 420 ). The fabric ( 100 ) delivered to the dying machine ( 400 ) is dyed by going through a process for a number of times, in which the fabric ( 100 ) circulates between the rolls ( 410 ) in the dying machine ( 400 ) and gets under the dyeing liquid ( 420 ) under a high temperature of 130 to 140° C. for two to four hours. Although the fabric ( 100 ) goes through the dyeing process described above, the spaces between the filament yarns are maintained, and the embodied creases do not dissolve.
[0016] Lastly, the fabric ( 100 ) dyed as described in the above is delivered to the drying machine ( 500 ), and dried under a high temperature of 185 to 195° C. for five to seven minutes. The fabric ( 100 ) being dried in such manner in the above, the widening between the filament yarns in the crease-forming process turns back closely to the original width, but the creases formed on the fabric ( 100 ) do not dissolve. Therefore, the width of the dried fabric ( 100 ) is 5 to 10% bigger than the original width. The fabric ( 100 ) with the creases formed in such a process described in the above is convolved around the roll ( 100 ) and shipped out.
[0017] Accordingly, the method of the present invention for forming vintage effect washer (which means for forming creases on synthetic fiber, hereinafter called ‘vintage effect washer’) is accomplished through the following steps: the 1 st step for convolving a sufficient length of the fabric ( 100 ) around the roll ( 110 ); the 2 nd step for delivering the fabric convolved around the roll ( 110 ) in the above to the crease-forming device ( 200 ) and blowing up hard by air on the fabric for two to four hours to widen the spaces between the yarns composing the filament, in the meantime, the filament yarns become twisted, thereby forming creases; the 3 rd step for delivering the crease-formed fabric ( 100 ) in the above to the crease-fixing device, heating the crease-formed fabric ( 100 ) under 90 to 100° C. to fabricate the creases, thereby fixing the creases; the 4 th step for delivering the crease-fixed fabric ( 100 ) in the above to the dyeing machine ( 400 ), circulating the crease-fixed fabric ( 100 ) between the rolls ( 410 ) under a high temperature of 103 to 140° C. for two to four hours, thereby dyeing the crease-fixed fabric ( 100 ); and the 5 th step for delivering the fabric dyed as described in the above to the drying machine ( 500 ), and drying the dyed fabric under a high temperature of 185 to 195° C. for five to seven minutes, thereby drying the dyed fabric ( 100 ).
[0018] Although the fabric manufactured in such a way is a synthetic fiber, it is very soft and gives high grade feeling and warmth retentivity like a natural fiber. Besides, differently from a natural fiber, the creases formed on the synthetic fiber as such do not dissolve from laundry and hold the original appearance made when creases are formed. | The present invention relates to a method for forming vintage effect washer by blowing up by air on one to another synthetic fiber filament yarns of a fabric, dyeing and drying the fabric with the filament yarns blown up as described in the above, getting the synthetic fiber partially back to the condition prior to the blowing-up of the synthetic fiber, thereby naturally producing a creased appearance. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to textile machinery in general, and more particularly to knitting machines and devices for designing knit images for the same.
2. Description of the Related Art
There are already known various constructions of devices for designing knit images for reproduction in knit products to be produced on knitting machines, among them those disclosed, for instance, in the published European patent document EP 0 640 707 A1, German patent document DE 44 31 898 A1 and the international patent document WO 94/11794. A device of this kind typically includes at least one storage device for storing data required for the production of the knit products on the knitting machine, at least one display device for displaying design images for the knit products, and at least one input device for altering the design images. By using such devices, it is possible to fully exploit the knitting capabilities of fully automated knitting machines. By using such devices, it is possible to manufacture knit products with complicated structures, highly complex color schemes or patterns, as well as complex contours or textures.
In the presently known designing devices of this kind, the input of the parameters of the knit product to be manufactured occurs in various input groups that can or must be edited separately. These input groups basically include shape instructions, color instructions, structure instructions, Jacquard instructions as well as loop size instructions. In addition to this, there must be entered yarn properties as well as machine parameters. From these instructions or input data, there are formed, by resorting to data processing techniques, control data on the basis of which a respective knitting machine is able to manufacture the desired knit product. The knit product is visualized on the display device of the designing apparatus, as a rule, in the form of a thread course presentation that depicts the knitting process—row by row—by respective symbols. In most known arrangements, the knit product is also entered into the system in this form and this information is subsequently converted by a conversion program into the control data for the knitting machine. In addition to that, the designing devices known from the above references are also equipped with other converting programs that are capable of converting or translating the thread course representation into a loop image representation that is capable of being then displayed. However, a direct conversion of a loop image representation into a thread course representation is not possible in these conventional devices.
As a result of the fact that the aforementioned designing devices require, for the generation of the design data for the knit product, the input of knit product instructions and of machine parameters and primarily display the thread course presentation of the knit product, they are predominantly aimed at a technically oriented user. For a style designer, who creates his or her designs in actual loop images, these designing devices are not suitable designing tools in that the loop image presentations can be generated in the known devices only in an operation following and resulting from the creation of the thread course presentation, so that the generation of the latter must be learned and mastered in order to be able to effectively employ the knit product designing device.
OBJECTS OF THE INVENTION
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a knit product designing device that does not possess the drawbacks of the known devices of this type.
Still another object of the present invention is to devise a designing device of the type here under consideration which is suited for use not only by technically oriented, but also by more artistically leaning, users.
It is yet another object of the present invention to design the above designing device in such a manner as to allow its proficient use even by persons who are not familiar with thread course presentation symbols and generation techniques.
A concomitant object of the present invention is so to construct the device of the above type as to be relatively simple in construction, inexpensive to manufacture, easy to use, and yet reliable in operation.
SUMMARY OF THE INVENTION
In keeping with the above objects and others which will become apparent hereafter, one feature of the present invention resides in a device for designing knit products to be manufactured on a knitting machine. This designing device includes at least one storage device for storing data required for the production of the knit products on the knitting machine, at least one display device for displaying design images for the knit products, and at least one input device for altering the design images. In accordance with the present invention, the designing device further includes means for processing data to be exchanged between the storage, input and display devices, including means for generating at least one knit image presentation and at least one corresponding thread course presentation for display as the design images on the display device, and means for simultaneously correspondingly altering one of the presentations as the other is being altered by using the input device.
A particular advantage of the designing device as described so far is that it is now possible by using the above designing device to utilize either one of the thread course and knit image presentations for the entry and/or alteration of data relating to the elements of the knit product, while the respectively other of such presentations or at least the data describing the same is changed accordingly in a simultaneous or concurrent fashion. Consequently, the designing device of the present invention is suited for use both by style designers and technically oriented users. In this respect, it is particularly advantageous for the processing means to further include means for sending the knit image presentation and the thread course presentation to the display device for simultaneous display thereon. Of course, if so desired, other presentations, such as those that more closely depict the machine operations, can be displayed on the display device as well.
Additional advantages are obtained when the processing means further includes means for sending at least one of the knit image presentation and the thread course presentation of a plurality of sections of the respective knit product to the display device for simultaneous display thereon. Such a simultaneous display may be achieved by resorting to the well-known window display technique. All of such windows are or equal rank during the editing, and they display images that are based on the same instructions or information. The effect of any modification in the thread course presentation on the knit product can be immediately observed in the reality-close knit or loop image presentation or rendition. This facilitates the spotting or recognition of errors or undesired effects. It is also possible in accordance with the present invention for the processing means to further include means for sending at least one of the knit image presentation and the thread course presentation of respective front and rear surfaces of the respective knit product to the display device for simultaneous display thereon.
It is especially advantageous when, in accordance with a further facet of the present invention, the generating means includes means for generating the knit image presentation as a reality-resembling, three-dimensional image of all elements of such a presentation including at least one of at least the loop size, tuck and float, wherein the individual elements, by performing predetermined offsetting and wrap-around around operations, may be tied in into the overall structure of the eventual knit product in directions different from the prevailing direction of the stitches of such a product. This is especially convenient to achieve when the input device includes means for entering and altering, for each needle position of the knit product, the kind, the shape and the size of the loop to be displayed in the knit image presentation. To this, there may be added data describing the kind of yarn(s) to be used in the manufacture of the knit product. In addition, the processing means may further include means for calculating, for forwarding to the generating means, information concerning the shape of the respective loop in dependence on the kind, size and shape of respective adjacent loops and in dependence on the properties of the knitting yarns to be used in the manufacture of the knit product.
Structural designs such as braid, aran etc. have sections in which loops from the typically vertically extending loop columns are wrapped around laterally around the loops of other loop columns. As a result of this deviation from the regular course, forces come into being in the knit product which influence the orientations of the loops. In a currently preferred embodiment of the designing apparatus of the present invention, there are offered to the user several kinds of presentations. For one, the basic structure of the design for the knit product may be kept unaltered in the knit image presentation and just the loops that are wrapped around loops others than those around which they would have been wrapped in their basic positions, being offset either laterally or in the height, are depicted extended to the extent corresponding to the difference between their basic positions and their new wrapped-around positions. However, the knit image presentation may also be, in accordance with the present invention, constructed in a manner that is closer to reality by taking into account the forces that act in the knit product as a result of such loop deviations in that even the loops that are situated in the vicinity of such deviated loops are shortened or lengthened to some extent in response to such forces. Moreover, the user is given the opportunity to change the positions of individual elements, such as loops, tuck or float correspondingly to his or her visual perception for the overall loop or knit image.
For the manufacture of knit products with loops of different magnitudes and yarn thicknesses, these loops can be rendered even in the knit product design in close correspondence to reality both as to the yarn thicknesses and the loop sizes.
Advantageously, the generating means for the thread course presentation includes means for generating respective symbols for all elements of the knit product to be manufactured including at least one of at least the loop size, tuck and float as well as for the needles of the knitting machine and their activities including knitting, not knitting, transferring, taking over, shedding and the like, and the symbol-generating means may preferably further include means for generating symbols for the parameters of the knitting machine including at least one of at least thread-guide movements, carriage movements, product withdrawal, needle bed offset and the like.
A significant design simplification can be achieved when, in accordance with another aspect of the present invention,
the processing means further includes means for combining groups of symbols of a thread course presentation into modules, and means for combining groups of loops of a knit image presentation into modules, and when the storing means includes means for storing the modules. Such modules may then be used either at a different location of the knit product, or in a different knit product altogether as a unit. Furthermore, it is proposed that the processing means further include means for inserting at least one of the modules into at least one of the presentations of a basic knit product, including means for tying in the loops of the module into the loop structure of the basic knit product in a manner that is technologically correct. The connection or tying in of the loops of the module in the knit image presentation with those of the basic knit product then corresponds to the actual conditions encountered in the knit product.
The designing device of the present invention may further include means in its processing means for graphically superimposing a plurality of rows of the respective thread course presentation into a single loop row and/or for contracting a plurality of rows of the respective knit image presentation into a single loop row on the display device. By resorting to this expedient, several rows of the knit image presentation can be contracted in such a manner that they occupy, in their vertical dimension, the same amount of space as merely a single row or course of the knit product. As a result, appliqués that would create spatial formations in the knit product can be presented in the knit image presentation appearing on the display device in a manner that is very close to reality. These means offer special advantages in the creation of Jacquard patterns. So, for instance, during the design of a three-color Jacquard knit, the representations of the yarns of the three colors can be contracted into a single row on the display device. Herein, the loops of the Jacquard back side are so arranged behind the Jacquard front side as it would eventually correspond to the actual appearance of the Jacquard knit product. Even in other two-surface knit products, the loops of the underlying surfaces are partially visible when looping on the first or top surface.
If the knit product is to include a skew region, then the latter can be presented on the display device horizontally, in a row-by-row manner corresponding to the knitting progress that is to take place on the knitting machine. In this presentation, the loops that are not being knit in the skew region are extended in their lengths to such an extent as corresponds to the knitting progress prior to the recommencement of their involvement in the knitting process. However, even here, the presentation can be, in accordance with the present invention, so “pushed together” that there results a reality-close presentation in which the loop rows of the skew region extend at an angle to the loop rows or courses of the basic knit structure.
Even Jacquard patterns can be presented in a so-to-speak distended condition in which all of the color knit rows needed for forming a single view row in the final knit product are presented above one another in the vertical direction. To achieve this, the processing means further includes means for graphically separating a single superimposed loop row of the respective thread course presentation into a plurality of constituent rows for display on the displaying device and/or means for graphically separating a single contracted loop row of the respective knit image presentation into a plurality of constituent rows for display on the displaying device.
Considerable additional advantages are obtained when the processing means further includes means for generating multiplicates of the modules for display on the display device and/or means for generating mirror images of the modules for display on the display device. The number of needles per knitting module both in height and in width is arbitrary. The same is also valid about the outer shape of the module.
Any knit module can be formed in two different ways: either as a section of a knit structure in knit image presentation or thread course presentation, or as a separate knit structure that is created in the knit image presentation or in the thread course presentation. Both of these presentations are automatically available for these knit modules. So, a knit module generated in the thread course presentation can be inserted at any time into the knit image presentation of the basic knit structure and can then be seen there in its knit image presentation as well. It is also possible for the knit modules to form the edges of a knit product. The modules may be introduced into the design for the knit product in such a manner as to horizontally or vertically adjoin each other, be offset with respect to one another, or be paced at predetermined distances from each other. There can even be specified the size of the are that is to be filled by a certain module. If the area to be filled does not correspond in one direction or the other to a multiple of the size of such a module, the remaining parts of this area are then filled with fractional parts of this module.
With respect to each of such knit modules, there may be stored in the storage device additional attributes which indicate the conditions of use for such a module. These attributes may include, for instance, the capability of mirroring the module from left to right or from above to below, or the unity of the module, that is the instruction that the module may only be used in the knit product in its entirety. With the aid of these attributes, it can also be prescribed that the module must be knit by itself as the knit product is being knit. Even the machine resolution in which the module must be generated, or the maximum permissible offset of the module can be given as attributes.
The following criteria may be taken into consideration during the insertion of a module into the basic knit structure of a knit product:
When loops are being formed in the same row of the basic knit product and the module, then the loops of the module replace the corresponding loops of the basic knit product. When, on the other hand, loops are being formed in the basic knit product but loops are carried over or skipped in the module, then a carry-over row is inserted into the basic knit structure. When loops are being carried over in the basic knit product but loops are being formed in the knit module, then the loops of the module replace in their region the loops of the next-following row of the basic knit product. In the event that loops are being carried over in the same row both in the basic knit product and in the module, then the offsetting and transferring movements are being conducted in a predetermined rank order. When loops are thrown off in a module knit row, then a throw-away row is introduced into the basic knit product, provided that a throw-away row does not already exist in the basic knit structure. Elevation references can be indicated both in the basic knit structure and in the module at which the knitting operation must not be altered by the module integration routines.
It is especially advantageous when the processing means further includes means for inserting at least one module of any type into at least one of the presentations of a basic textile product of any type. In this context, the user may give instructions about how the automatic control of the operation is to react at the region of the module to the different knitting process control cards. Such instructions may be defined individually for each needle that lies immediately within or without the module contour. So, it can be preordained in the course of which knitting operation type—loop, tuck, no-loop—of the respective needle at the border region the modification of the knit structure is to take place. Besides, it can be specified how the basic knit structure of the border region is to be modified in dependence on the operation type of the needle at that region. To this end, it is proposed for the processing means to further include means for defining border modules between at least one of the presentations of the module and at least the corresponding one of the presentations of the basic knit product. Such a border or transition module may be situated directly at the boundary between the module and the basic knit structure; however, it may even be placed, when necessitated by knitting operation consideration, at a distance from this boundary.
The designing device may further include a Jacquard generator for the design of the connecting structure of the Jacquard front side with the Jacquard rear side of the knit product in at least one of the knit image and thread course presentations. The colors of the visible side can be predetermined either in the knit image or thread course presentation, or as a loop-rastered color image. All Jacquard connecting structures between the visible side and the back side, which embody the state of the art in the knitting technology, may already be contained in the storage device of the designing apparatus and be presented to the user in a menu form for utilization. Once the user has selected a connecting structure from the respective menu, the Jacquard generator automatically generates the desired connecting structure, depending on the visible Jacquard side. However, the user may also use the Jacquard generator to define his or her own connecting structure, and to store the same for future reference.
After the knitting instructions have been entered to alter either the knit image presentation or the thread course presentation, the processing means calculates from such data the control data for controlling the operation of the knitting machine. However, the translation of the knitting instructions into such control data is sometimes not unique. So, for instance, there may be several possibilities of implementation. Therefore, the designing device may, in accordance with another feature of the present invention, include interactive means for influencing the translation of the design images of the through the input device knit product into control data for the knitting machine. In this manner, it is possible to manually choose one of several translation possibilities of the design images into control data for controlling the operation of the knitting machine. Moreover, the storage device may advantageously include storage areas for storing frequently used translation algorithms between the design images and control data for the knitting machine as entered by the interactive means. This has the advantage that, when a designer of a new product encounters a certain translation problem, he or she may resort to the use of an already available algorithm, so that the latter need not be entered again. This interactive means may also be so set up that the user can determine for all detected translation problems if his or her interactively made selections and/or changes are to be automatically used throughout the particular knit product, or generally for all knit products to be manufactured.
The present invention is also directed to a method of designing knit products to be manufactured on a knitting machine, which method comprises the steps of generating at least one knit image presentation and at least one corresponding thread course presentation of the respective knit product, displaying such presentations, and simultaneously correspondingly altering one of the presentations when and as the other is being altered. There are advantageously also provided the further steps of converting the respective one of the knit image presentation and the thread course presentation into design data for the knit product, and storing such design data for shared use in both of the presentations. This means that a common set of data is generated and stored for both of such presentations of the product to be manufactured, which facilitates the simultaneous transfer of the alterations in one of the presentations into the other.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, 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 drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic view showing, in principle, a designing device embodying the present invention, together with a flat knitting machine;
FIG. 2 is another diagrammatic view presenting, in principle, a data storage unit as well as a loop image presentation and a thread course presentation of a knit section;
FIG. 3 is a front elevational view of a monitor with windows containing various loop image and thread course presentations;
FIG. 4 is a loop image presentation of a loop product;
FIG. 5 is a loop image presentation of a border region of a loop product;
FIGS. 6 a and 6 b are two different loop image presentations of a loop cross-over area of a knit product;
FIG. 7 is a loop image presentation of a knit product containing loops of different dimensions and yarn thicknesses;
FIGS. 8 a and 8 b are two different loop image presentations of a knit product with a wave appliqué;
FIGS. 9 a and 9 b are front and rear views of a two-color Jacquard knit product, in loop image presentations;
FIGS. 10 a and 10 b are two different possibilities of presenting a skew region of a knit product;
FIG. 11 is a thread course presentation of a braided knit region;
FIGS. 12 a and 12 b are thread course presentations of a two-color Jacquard knit product in exploded and superimposed forms;
FIGS. 13 a and 13 b are thread course presentations of a skew region of a knit product in exploded and contracted forms;
FIGS. 14 a to 14 c are diagrammatic representations of a knit product module with indications of boundary regions of the knit product module and of the surrounding basic knit product;
FIG. 15 is a diagrammatic representation of a knit product module with a boundary module inserted in a basic knit product;
FIG. 16 is a diagrammatic representation of an input mask of a Jacquard generator; and
FIGS. 17 a and 17 b are diagrammatic presentations of a knit product composed of several regions, in the original size and in an expanded size.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing in detail, and first to FIG. 1 thereof, it may be seen that it depicts one possible configuration of a device for designing products according to the present invention. Such products include a great number of adjacent and/or interengaging loops and are produced by machinery using a multitude of cooperating needles, so that they will be referred to throughout, sometimes interchangeably but typically without distinction, as loop or knit products regardless of which precise technique and/or machinery (knitting, flatbed, doubleknit, frame, Jacquard-controlled, etc. whether using a continuous thread or a plurality of threads) is being employed to produce the same. The designing device mentioned above includes a computer 1 , a monitor 3 to serve as a display device, as well as a keyboard 2 and a graphic tablet 4 to serve as input devices. Furthermore, an external mass storage device 6 , as well as a printer 5 to serves as an additional display device, are connected with the computer 1 . The control data that are generated by this designing device are supplied, in the illustrated example, to a flat knitting machine 8 , as indicated by an arrow 7 .
FIG. 2 shows two different design presentations that can be displayed on the display device 3 of the designing system or device. These presentations are a loop image presentation 11 and a thread course presentation 12 of a loop product. The two presentations 11 and 12 are generated from data stored in a shared storage device 10 that is indicated in the drawing only in a simplified, diagrammatic form. The very same data set is altered on the storage device 10 during the editing and alteration of any one of the two presentations 11 and 12 as well. In this manner, it is possible to achieve, when one of these two presentations is altered, a simultaneous corresponding change in the respective other of these presentations.
In FIG. 3, the monitor 3 shown in general terms in FIG. 1 is presented at a larger scale. Several display windows 20 , 21 , 22 and 23 are shown to be displayed on the monitor screen. Of these windows 10 to 23 , the windows 20 and 21 contain loop image presentations, while the remaining windows 22 and 23 contain thread course presentations. By resorting to this window technique, it is thus possible to simultaneously make visible loop image presentations as well as thread course presentations of several sections of the loop product.
FIG. 4 illustrates a section of a loop image presentation, from which the closeness-to-reality of this presentation type is evident. There are shown many and particularly identified several elements of the product, such as a plain stitch or loop 30 , a plain loop 31 pulled up or extending over two rows or courses of the product, a plain loop 32 that is hanged around one column to the left, and a loop 33 that is hanged around one column to the right. A further loop identified as 34 is a plain loop or stitch that is pulled up or extends over three rows or courses of the knit product. All of the loops are shown in three dimensions and they can, of course, also be rendered in colors; advantageously, the colors of the threads in the rendition appearing on the screen correspond to the colors of the threads or yarns used to make the actual product.
FIG. 5 reveals a loop image presentation of a boundary region of a loop or knit product. Two plain stitches 35 and 36 are connected with one another by a connecting loop 37 . In this manner, the presentation of FIG. 5 corresponds exactly to the actual thread course in the corresponding knit product piece.
FIG. 5 reveals a loop image presentation of a loop product with a loop cross-over, in two different presentation modes. In FIG. 6 a , only the loops that actually cross over are shown at an angle to the vertical, whereas all other loops, especially loops 40 and 41 that are situated directly below the mutually crossing loops, are drawn completely unchanged. In contradistinction to this, the conditions are shown more realistically in FIG. 6 b . Herein not only the loops or stitches that actually cross one another extend at respective angles to the vertical, but also the adjoining loops or stitches, for instance the loops 40 ′ and 41 ′, as it occurs in the actual knit product piece as a result of the forces acting on the various loops at the region of the loop cross-over.
In FIG. 7, there is shown a loop image presentation of a knit product with loops of different magnitudes of yarns with different thicknesses. Even here, the transition between relatively small plain stitches 45 made of relatively thin yarn and relatively large stitches 46 made of relatively thick yarns are shown in a manner close to the real-life conditions.
FIG. 8 relates to a loop image presentation of a knit product including a wave appliqué 51 indicated by a darker color. In FIG. 8 a , the two knit rows or courses of the wave appliqué 51 are shown in their normal sizes, while he loops 52 preceding and succeeding the wave appliqué 51 are shown in an extended form. Hence, FIG. 8 a is a rather theoretical presentation which, however, shows the wave appliqué 51 proper very well. In contrast, a presentation that is closer to reality has been chosen for FIG. 8 b . The two loop courses of the wave appliqué 51 ′ are contracted here and the remaining loops 50 ′ are shown in their original dimensions and not extended. In order to permit such kinds of presentations, the designing device or system of the present invention includes devices for graphical parting and superimposition of loops and loop rows.
FIG. 9 a shows a front side of a two-color Jacquard knit product in a loop image presentation, and FIG. 9 b a rear side of the corresponding loop product. It is possible to show both of these presentations simultaneously on the screen of the monitor 3 .
In FIG. 10, there are shown two different kinds of presentation of a skew region, indicated by loop symbols. In FIG. 10 a , two skew regions 61 and 63 are shown to extend horizontally, correspondingly to the way they are actually produced on the knitting machine. Region 60 is a loop region immediately preceding the first skew region 62 , whereas region 64 is the substantially triangular region immediately succeeding the second skew region 63 . The two skew regions 61 and 63 are separated from each other by an intervening region 62 exhibiting a full knit product width. Respective loops 65 and 66 situated in the skew regions 61 and 63 , which hang in the course of the manufacture on needles that temporarily do not participate in the knitting process of the knitting machine while the overall skew region is being formed, are shown to be extended in this particular presentation. The respective loop extensions stretch over as many rows as the number of knitting cycles during which the associated needles do not participate in the knitting process. In the reality-closer presentation of FIG. 10 b , the loops of the intervening region 62 ′ extend at a slant, whereas all of the loops in the skew regions 61 ′ and 63 ′ are shown in their unexpanded sizes.
FIG. 11 shows a first thread course presentation of a 2-by-3 braid knit product. Respective rows 1 , 2 , 4 and 8 contain knitting instructions for loop formation in a front and a rear needle bed V and H of a flat knitting machine, respectively. In rows 3 and 5 , there are provided loop-around instructions from the front needle bed V to the rear needle bed H for loops associated with needles 9 , 10 and 11 , or 6 , 7 and 8 , respectively. Rows 6 and 7 contain needle bed offset and loop-around instructions. Thus, in row 6 , the loops of the needles 6 , 7 and 8 from the read needle bed H are shifted by three columns or loops to the right and transferred to or hung around the corresponding needles of the front needle bed V. In the row 7 , there is indicated the looping of the loops of the needles 9 , 10 and 11 from the rear needle bed H around the corresponding needles of the front bed V as being shifted to the left by three columns or loops. In contrast to the loop image presentation, the thread course presentation is no longer close to what the knit product would look like in reality; rather, it is produced by utilizing respective symbols. Hence, the thread course presentation corresponds more closely to the operations that the respective knitting machine must perform during the production of the respective knit product.
In FIG. 12, there are presented two possibilities of the thread course presentation of a two-color Jacquard knit product. FIG. 12 a shows a separate knitting row for each of the two colors of the Jacquard knit product, wherein the rows 1 , 3 , 5 and 7 are associated with one of these colors whereas the rows 2 , 4 , 6 and 8 correspond to the other color. In FIG. 12 b , the respective associated ones of the aforementioned rows are superimposed and thus form respective appearance rows that correspond to the knit rows as they actually appear in the finished knit product. Herein, respective loops 70 are the loops that are of one of the colors, whereas loops 71 are loops that are formed in the other color.
FIG. 13 shows two possibilities of the thread course presentation of skew regions of a knit product piece. In FIG. 13 a , a first knit product region 80 extending over a full knit product width is adjoined by a first skew region 81 in which an increasing number of needles ceases to participate in the knitting process. Then, there comes a knit product region 82 extending over the entire width of the knit product, before there is encountered a further skew region 83 within which an increasing number of needles commences its participation in the knitting process, until the entire knit product width is reached again in a region 84 . The presentation shown in FIG. 13 b is closer to reality, though. Here, the loops of the intermediate region 82 ′ extend at a slant with respect to the knitting progress direction, akin to how they subsequently also behave in the finished knit product. The remaining regions 80 ′, 81 ′, 83 ′ and 84 ′ remain unchanged in their presentation with respect to their similarly designated counterparts in FIG. 13 a.
FIG. 14 a focuses on the insertion or incorporation of a knit module 110 that is delimited by a thick black line into a basic knit product 100 . Respective boundary loops of the knit module 110 relative to the basic knit product 100 are denoted by the reference numeral 111 , whereas the boundary loops of the basic knit product 100 with regard to the knit module 110 are designated as 101 . For the incorporation or tying-in of the knit module 110 into the basic knit product 100 , it is possibly necessary to make some advance changes in these boundary loops 101 and/or 111 to assure that the knit module 110 is correctly inserted and tied in into the basic knit product 100 . In FIG. 14 b , there is presented a stylized templet 200 for an arbitrary boundary loop 101 or 111 . Here, the symbol 201 characterizes the operation of a needle on a front needle bed V, whereas the symbol 203 is indicative of the operation of a needle located on the rear needle bed H. An inclined slash 202 serves merely as a separation symbol between the symbols 201 and 203 for the front and read needle beds V and H, respectively. However, FIG. 14 b contains not only the instructions for a boundary loop 200 , but also, in a logical AND operation coupling, even the instructions for the respective adjoining or neighboring needles and/or loops 200 ′ and 200 ″. In FIG. 14 c , there is shown an entire boundary module 300 which, in the illustrated example, consists of six needles or loops 300 ″. Depending on the pattern of the knit module 10 and that of the basic knit product 100 , such a boundary module may stretch over a greater or a lesser number of needles. This is indicated in FIG. 15 . In there, the knit module 110 has been already incorporated into the basic knit product 100 . The boundary needle 5/5 of the basic knit product 100 needs an entire boundary module 300 , which modifies the basic knit pattern, in order to be able to correctly tie-in the knit module 110 into the basic knit product 100 . The module 300 extends over three needles 5/5, 4/5 and 3/5.
FIG. 16 shows an input mask or templet 400 of a Jacquard generator, by means of which a three-color Jacquard knit product can be designed. Respective columns 410 , 420 and 430 of the mask 400 are respectively associated with the three colors. The pattern that had been chosen here for each of the three colors extends over two needles in width, for which reason each of the respective columns 410 , 420 and 430 are subdivided again into two sub-columns 411 and 412 ; 421 and 422 , and 431 and 432 , respectively. Respective rows 440 and 450 correspond to the respective appearance rows of the Jacquard pattern. These two rows 440 and 450 are repeated again and again over the height of the knit product. Each of the rows 440 and 450 is subdivided once more, this time in three sub-rows 441 to 443 and 451 to 453 , respectively corresponding to the three colors of the knitting threads being used. In the rectangular boxes obtained as a result of this fine subdivision of the columns 410 , 420 and 430 and of the rows 440 and 450 , which rectangles correspond to respective needle positions, it is indicated for each needle of the front and rear needle bed V and H whether or not a loop is to be produced. The instructions for the front and rear needle beds V and H are separated from each other in each instance by a forward slash 461 . So, for instance, a horizontal dash 460 in the last sub-row 443 in the first sub-column 411 is indicative of the instruction for the corresponding needle of the front needle bed V not to operate. However, a loop 450 is produced on the rear needle bed H at the same needle position ( 443 / 411 ). At the next adjacent needle position ( 443 / 412 ), neither the front nor the rear needle knits. At the following adjacent needle position ( 443 / 413 ), a loop 462 is formed once more on the read needle bed H; two positions later ( 443 / 415 ) another loop 463 is formed, this time on the front needle bed V. With the aid of this mask or templet, even very complex or intricate Jacquard patterns can be entered and a corresponding loop image presentation or thread course presentation may be displayed on the display device 3 on its basis.
A knit module 510 is shown in FIG. 17 a of the drawing; this module 510 is composed of several components, namely a central area 500 , edge areas 505 , 506 , 507 and 508 , and comer areas 501 , 502 , 503 and 504 . The knit module 510 is especially suited for stretching, that is its expansion in a knit product piece as indicated in FIG. 17 b . To this end, the central area 500 is duplicated or multiplicated as many times as needed to cover the desired region, and the edge areas 505 , 506 , 507 and 508 are extended correspondingly. The corner areas 501 , 502 , 503 and 504 remain unaltered, but are shifted in positions accordingly.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the type described above.
While the present invention has been described and illustrated herein as embodied in a specific construction of a device for designing and visualizing loop or knit products, it is not limited to the details of this particular construction, since various modifications and structural changes may be made without departing from the spirit of the present invention. So, for instance, other data, instructions or commands that are relevant to the production of a knit product of any imaginable shape and/or pattern may be entered into and processed by the system. Moreover, the designing device of the present invention is suited not only for the design of articles of apparel, but also for the design of technical knits.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.
What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims. | A device for designing knit products to be manufactured on a knitting machine includes at least one storage device for storing data required for the production of the knit products on the knitting machine; at least one display device for displaying design images for the knit products; and at least one input device for altering the design images. Data to be exchanged between the storage, input and display devices is processed to generate at least one knit image presentation and at least one corresponding thread course presentation for display as the design images on the display device, and one of the presentations is simultaneously correspondingly altered as the other is being altered by using the input device. | 3 |
[0001] Applicant claims, under 35 U.S.C. §119, the benefit of priority of the filing date of Apr. 11, 2003 of a German patent application, copy attached, Serial Number 103 16 870.2, filed on the aforementioned date, the entire contents of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a position measuring system.
[0004] 2. Discussion of Related Art
[0005] Such position measuring systems are used to measure travel distances or angles of a moving component. To detect the motion of the component, a detector device is accommodated in protected fashion in a housing. Via a cable, the position-dependent electrical measurement signals are carried to the outside from the interior of the housing and conducted onward to a subsequent electronic unit for measurement value processing.
[0006] From German Patent Disclosure DE 195 43 372 A1, one such position measuring system is known, in the form of an angle measuring device. A sheath is crimped around the shielding mesh of the cable; this sheath engages in a fit and as a result forms a tension relief for the cable. The sheath and the fit are covered by a cap.
[0007] A disadvantage of this device is the requirement for a sheath around the shielding mesh and the lack of tightness in the cable leadthrough.
OBJECT AND SUMMARY OF THE INVENTION
[0008] An object of the present invention is to disclose a position measuring system in which a shielded electrical cable is fixed especially simply to a housing of the position measuring system.
[0009] This object is attained according to the present invention by a position measuring system having a housing with a wall, the wall having an opening and including a deformation. A measurement device accommodated in the housing, the measurement device detects and/or processes measurement values and outputs a position-dependent measurement signal. A cable including a shield, wherein the cable is positioned within the opening and is electrically connected to the measurement device so as to carry the measurement signal. The deformation of the wall fixes the cable in the opening and for binding the shield to the housing.
[0010] The opening in the wall of the housing through which the shielded cable is passed is reduced in size by a deformation of the wall or a crimping, thereby fixing the cable in the opening.
[0011] In a preferred embodiment, the shielding mesh is upended or turned back onto the jacket of the cable, and the deformation has a first portion in which there is no shielding mesh between the deformed wall of the housing and the jacket, and the deformation has a second portion in which the deformed wall of the housing contacts the upended or turned back shielding mesh.
[0012] This has the advantage that the first portion assures the tightness of the cable leadthrough, and the second portion assures the binding of the shield to the electrically conductive housing.
[0013] With the present invention, simple, space-saving fixation and shielding binding of the cable to the housing of the position measuring system are possible.
[0014] The present invention will be described in further detail in terms of exemplary embodiments in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a cross-sectional view of an embodiment of an angle measuring device taken along an axis of a shaft of the angle measuring device in accordance with the present invention;
[0016] [0016]FIG. 2 is a cross-sectional view of the angle measuring device of FIG. 1 in the region of the cable leadthrough;
[0017] [0017]FIG. 3 is a cross-sectional view taken along line 3 - 3 of FIG. 2 of the housing of the angle measuring device of FIG. 2;
[0018] [0018]FIG. 4 is a cross-sectional taken along line 4 - 4 through the housing of FIG. 3;
[0019] [0019]FIG. 5 is a cross-sectional view through the housing of a second embodiment of an angle measuring device in accordance with the present invention; and
[0020] [0020]FIG. 6 is a cross-sectional view through the housing of a third embodiment of an angle measuring device in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] The position measuring systems shown in the drawings and described as examples here are angle measuring devices. These angle measuring devices have a shaft 1 for connection to a body to be measured, whose angular position is to be measured. The shaft 1 is rotatably supported in a base body 2 —also called a stator or flange. For angle measurement, the shaft 1 is connected for instance to a motor shaft and the base body 2 to the motor housing that is stationary relative to it.
[0022] On the shaft 1 , a code disk 3 with an incremental and/or absolute code is mounted in a manner fixed against relative rotation and can be scanned photoelectrically, magnetically, capacitively, or inductively. In the example, the code disk 3 is scanned photoelectrically. For this purpose, a light source 4 is used, which outputs a focus beam which is modulated as a function of position by the code disk 3 . The modulated light reaches a measurement device, such as detector device 5 , which is disposed on a printed circuit board 6 . Also located on the printed circuit board 6 is the stationary part 7 . 1 of a plug connection 7 . The corresponding part 7 . 2 of this plug connection 7 is secured to a cable 8 that leads to the outside.
[0023] For protecting the detector device 5 , there is a cylindrical or cup-shaped housing 9 , which is closed on its face end and is secured over the circumference to the base body 2 . Protection against electromagnetic interference is assured because the housing 9 comprises electrically conductive material and is in contact with the electrically conductive base body 2 . The housing 9 and the base body 2 are connected, via a shield in the form of a shielding mesh 8 . 1 of the cable 8 , to a reference potential for diversion of electrical charges. This connection is shown in detail in FIGS. 2-4.
[0024] An opening 10 extending transversely to the shaft axis A is made in the end wall 9 . 1 of the housing 9 . The metal shield is disposed in the form of a shielding mesh 8 . 1 around signal lines 8 . 2 of the cable 8 , and a plastic jacket 8 . 3 is located around the shielding mesh 8 . 1 . The shielding mesh 8 . 1 is stripped bare over a short length, and the stripped portion is upended/turned rearward or folded over rearward onto the outer circumference of the jacket 8 . 3 . In this state, the cable 8 is passed through the opening 10 . The length of the opening 10 for receiving the cable 8 is selected such that, viewed in terms of its length from the outside toward the housing interior, it has a first portion L 1 , in which a region of the cable 8 without the upended or turned back shielding mesh 8 . 1 is located, and a following second portion L 2 , in which one region of the cable 8 with the upended or turned back shielding mesh 8 . 1 is located over the jacket 8 . 3 .
[0025] By a plastic deformation, crimp or indentation 11 of the wall 9 . 1 of the housing 9 , in both portions L 1 , L 2 the opening 10 is reduced in diameter, and as a result the cable 8 is fixed in tension-proof fashion by positive engagement in the opening 10 of the housing 9 . The first portion L 1 guarantees a tight closure, since the wall 9 . 1 of the housing 9 directly contacts the elastic jacket 8 . 3 of the cable 8 over the entire circumference and thus securely seals off the opening 10 . The second portion L 2 guarantees a secure electrical contact of the shielding mesh 8 . 1 with the housing 9 and thus shielding of the housing 9 against electromagnetic interference. Damage to the signal lines 8 . 2 is prevented, since the deformation of the wall 9 . 1 in both portions L 1 , L 2 is made by plastic deformation of the jacket 8 . 3 .
[0026] To simplify installation and for secure positioning of the cable 8 in the opening 10 prior to the deformation, a step 12 is made in the opening 10 , as a stop for the end of the jacket 8 . 3 , as shown in FIG. 3.
[0027] As also particularly clearly shown in FIGS. 3 and 4, the end wall 9 . 1 that has the opening 10 is embodied with a greater thickness than the rest of the wall of the housing 9 . The deformation 11 is made on one side by a half-round form as a bead, for the sake of a good flow of material. To improve the flow of material, the deformation 11 also has a chamfer at both the beginning and end in the longitudinal direction of the opening 10 .
[0028] For an outer diameter of the jacket of the cable 8 of approximately 6 mm, a length of the deformation 11 of approximately 9 mm has proved good, in which case the first portion L 1 has a length of approximately 6 mm and the second portion L 2 has a length of approximately 3 mm.
[0029] The housing 9 is produced from electrically conductive metal, in particular aluminum or aluminum alloy, by extrusion or diecasting. The opening 10 , in extrusion, is a bore made afterward by metal-cutting machining, while in diecasting it can be provided in the mold.
[0030] In FIG. 5, a modified version of the angle measuring device of FIGS. 1-4 is shown. Unlike the first angle measuring device of FIGS. 1-4, in this second angle measuring device, an adhesive 13 is additionally placed between the jacket 8 . 3 of the cable 8 and the housing 9 . This adhesive 13 is advantageously provided over the entire circumference of the cable 8 in the opening 10 and assures even better sealing.
[0031] In FIG. 6, a further modification of the angle measuring device of FIGS. 1-4 is shown. In a distinction from the first angle measuring device of FIGS. 1-4, in this third angle measuring device there is an elastic intermediate ply 14 , for instance in the form of a rubber hose, between the jacket 8 . 3 of the cable 8 and the housing 9 . This intermediate ply 14 is thrust over the jacket 8 . 3 and partially under the upended or turned back shield 8 . 1 . The advantage of this kind of intermediate ply 14 is that an elastic deformation and thus good tightness are assured by a suitable choice of material for the intermediate ply 14 . The tightness is thus not exclusively dependent on the deformability of the jacket 8 . 3 of the cable 8 .
[0032] In all the exemplary embodiments shown in FIGS. 1-6, instead of the radial course of the cable 8 shown, an axial course of the cable 8 can be provided, by embodying one side wall of the housing in a swelled form and making an axially extending opening in this swelling of material for receiving and fixing the cable. The versions described at length and this alternative version have the advantage of a space-saving arrangement that does not enlarge the radial circumference of the housing, which is advantageous particularly for building the angle measuring device into the tubular interior of a housing of an electric motor.
[0033] The housing can also be a component of a scanning arrangement of a length measuring instrument. Then the housing can cover a device for detecting measurement values either in the form of a detector arrangement, or only in the form of an evaluation device for processing scanning signals of a detector arrangement disposed outside the housing.
[0034] Besides the exemplary embodiments described, it is understood that alternative variants also exist within the scope of the present invention. | A position measuring system having a housing with a wall, the wall having an opening and including a deformation. A measurement device accommodated in the housing, the measurement device detects and/or processes measurement values and outputs a position-dependent measurement signal. A cable including a shield, wherein the cable is positioned within the opening and is electrically connected to the measurement device so as to carry the measurement signal. The deformation of the wall fixes the cable in the opening and for binding the shield to the housing. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to safety interlock systems for pressure vessels and particularly to such systems which are operable with mechanisms for latching a lid to a pressure vessel and for preventing release of the latching mechanism while potentially hazardous pressure conditions exist within the vessel.
1. Description of the Prior Art
Pressure vessels have long been known to be useful in a wide variety of situations, such vessels invariably including a lid which allows access to the interior of the pressure vessel. Such lids must be sealed on closure of the vessel and positively latched by a mechanism which preferably allows ready opening and closure of the lid with a minimum of effort but with a maximum of safety. A common environment in which pressure vessels are used relates to the cooking of foods under pressure, such devices typically being referred to as pressure cookers or pressure fryers. In this use environment, foods are typically cooked in oil and, under the cooking conditions, moisture in the food is released into the oil and causes relatively high pressure conditions to exist within the vessel. While these pressure conditions primarily act to cook foods within the pressure cooker, the pressure conditions also represent potentially hazardous conditions which require care to be taken in the design of the pressure cooker to prevent inadvertent and abrupt removal of the pressure cooker lid during and immediately after the cooking operation when pressure conditions within the cooker are high. Such an inadvertent opening of the pressure cooker allows immediate expansion of the moisture entrapped in the oil, the result being an explosion of the hot oil through the opening normally secured by the lid. An inadvertent and untimely opening of a pressure cooker lid in this manner thus represents a substantial hazard to an operator of the cooker. While latching mechanisms have previously been devised for maintaining the lid of a pressure cooker in place against pressure conditions existing within the cooker, the use of a safety interlock system capable of preventing inadvertent operation of the latching mechanism to open the pressure cooker has been devised in order to prevent opening of a pressure cooker while hazardous pressure conditions exist within the cooker. The safety interlock thus provides an added check to the operator's decision as to whether conditions within the cooker allow safe opening of the cooker. Such a safety interlock must be reliable and relatively incapable of being fouled and thus rendered inoperable even under the conditions encountered in a commercial cooking operation.
Stoermer, in U.S. Pat. No. 3,976,218, provides a pressure fryer safety interlock which prevents operation of a screw spindle and maintains a closure bar in sealing engagement with the lid of a pressure fryer. The Stoermer safety interlock comprises a vertically extending pin which is biased upwardly into an effective engagement with the screw spindle by pressure within the fryer acting against a lid liner, the liner biasing the pin upwardly to prevent rotation of the screw spindle. Since the channel within which the pin is held is vertically disposed with the upper end thereof being essentially open to ambient, fouling of the locking mechanism due to dripping of congealable liquids as well as dropping of solid matter such as breading and the like associated with a cooking operation provides the potential for inadequate operation of the locking structure. Failure of such a safety interlock to operate is hazardous even though the operator of the pressure cooker must primarily rely upon his own personal judgment as to the safety of proceeding with the opening of the pressure cooker.
The present invention intends improvement over the prior art including the safety interlocks previously proposed for use with pressure fryers and the like, the invention particularly providing a safety interlock system operable with a latching mechanism typically employed in a lid closure system of a pressure cooker or similar vessel to positively prevent opening of a pressure vessel lid while hazardous pressure conditions exist within the vessel. According to the present invention, the safety interlock of the present invention is configured to inhibit fouling of the mechanism by congealable liquids and solids such as breading and the like. Further, the present safety interlock is configured to maintain locking capability even during power failure. The particular structure of the present safety interlock system allows essentially continuous operation but at minimum temperature and with minimum wear such that the failure potential of the safety interlock system is minimized. Accordingly, operation of a pressure vessel such as a pressure cooker or fryer is rendered safe to a degree not heretofore realized in the art through the use of the present invention.
SUMMARY OF THE INVENTION
The invention provides a pressure-activated safety interlock system for a pressure vessel, particularly a pressure fryer employed principally for cooking chicken or comparible foods in oil under pressure as is well known in the art. The safety interlock system of the present invention is particularly useful with the latching mechanism described in United States patent application Ser. No. 298,481, filed Sept. 1, 1981, the disclosure of which is incorporated hereinto by reference. The present safety interlock system particularly is intended to substitute for the pressure-operated safety lock described in the aforesaid United States patent application. The latching mechanism with which the present invention finds particular utility and which is disclosed in the aforesaid United States patent application is disposed at the distal or free end of a bar which extends across a lid of a cooker pot, the lid being adapted to sealingly engage upper edges of the pot. The bar is pivotally connected anteriorally to the cooker pot and is pivotally joined to the lid medially of the length of the bar and essentially centrally of the lid. An elongate spindle is mounted to the free end of the bar and has a hook element at one end thereof which is adapted to engage a catch or lug formed in the pot. Displacement of the spindle in a direction upwardly or outwardly of the lid causes the hook element to engage the catch and to force the lid over the peripheral edges of the pot opening to seal the opening in the manner described in the aforesaid United States patent application.
Use of the latching mechanism of Ser. No. 298,481 with the present safety interlock system does not require modification of the latching mechanism or of the lid and closure bar structures. In the system of Ser. No. 298,481, a pin is horizontally mounted within a cylindrical pressure receptacle, the receptacle being mounted upon the closure bar and communicating through a pressure tube with the interior of the cooking pot. A first end of the pin extends outwardly of a forward end of the pressure receptacle to engage one of a plurality of radially disposed slots formed in the hub of the latching mechanism, thereby to prevent operation of the latching mechanism and thus opening of the lid while the pin is engaged with the hub. The present safety interlock system continues use of the pin to engage the hub of the latching mechanism and thus prevent operation of said latching mechanism. However, the pin of the present safety interlock system is carried by a pull-type DC solenoid valve which maintains the pin out of engagement with the hub of the latching mechanism while power is supplied to the solenoid valve. The solenoid valve electrically connects to a pressure switch which discontinues power to the solenoid valve when the pressure within the cooker reaches a predetermined value. Discontinuation of electrical power to the solenoid valve thus results in a spring within the solenoid valve causing the pin to be biased outwardly in a direction toward the hub of the latching mechanism to allow engagement of the distal end of the pin with the radially disposed slots formed in said hub. Since the pin is directed into a locking position when power is discontinued to the solenoid valve, a power failure or other inadvertent discontinuation of power will cause the present safety interlock system to engage the latching mechanism and prevent opening of the pressure vessel, thereby providing additional operator safety even during periods of emergency power loss. The safety interlock system of the invention accordingly prevents opening of the pressure vessel while sufficient pressure exists within the pressure vessel to constitute a hazard in the event of inadvertent opening of the lid.
The pull-type solenoid valve preferably used according to the invention is operated by direct current, an AC/DC rectifier being interposed between the solenoid valve and the pressure switch which activates the solenoid valve. By operation of the solenoid valve with direct current, lower heat loading is experienced relative to the use of an AC solenoid, thereby increasing the useful life of the solenoid portion of the system and reducing the probability of service failure. In virtually continuous service, substantially reduced operating temperatures are encountered with the DC solenoid valve.
Accordingly, it is a primary object of the present invention to provide a simple, safe and reliable safety interlock system capable of preventing operation of a latching mechanism used to maintain the lid of a pressure vessel such as a pressure fryer in locked position while potentially hazardous pressure conditions exist within the pressure vessel.
It is another object of the present invention to provide a safety interlock system for a pressure vessel wherein the interlock system is resistant to wear and failure in use, including failure during inadvertent discontinuation of power.
It is a further object of the invention to provide a safety interlock system for a pressure fryer which cooperates with a latching mechanism to prevent operation of the latching mechanism in a lid-opening sense when hazardous pressure conditions exist within a cooking pot of the fryer, the safety interlock system comprising a pin disposed in a horizontal sense and which engages a hub of the associated latching mechanism to prevent operation of the latching mechanism while hazardous pressure conditions exist within the fryer or during power failure.
Further objects and advantages of the invention will become more readily apparent in light of the following detailed description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view in partial section of the safety interlock system of the present invention;
FIG. 2 is a plan view of the present safety interlock system; and,
FIG. 3 is a diagram illustrating the functional interrelationships of the several components of the present safety interlock system.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, the safety interlock system of the invention can be seen generally at 10 and is seen to be mounted generally on upper portions of cabinet 12 of a pressure cooker which includes a frying pot 14. Although not shown in the drawings, the cabinet 12 also houses conventional mechanisms such as oil filtration apparatus, control apparatus and the like in a well-known fashion, the pressure cooker being essentially conventional in structure and operation in essentials other than the structure and operation of the safety interlock system 10. In particular, the pressure cooker and latching mechanism shown and described in United States patent application Ser. No. 298,481, filed Sept. 1, 1981 are preferred for use with the present safety interlock system 10. In order to simplify description of the use environment of the safety interlock system 10, the disclosure of United States patent application Ser. No. 298,481 is incorporated hereinto by reference. It is further to be understood that the safety interlock system 10 of the present invention essentially substitutes in the disclosure of Ser. No. 298,481 for the pressure-operated locking mechanism 32 of the aforesaid patent application. As is the case with the pressure-operated locking mechanism 32 of the aforesaid patent application, the safety interlock system 10 acts in concert with the latching mechanism referred to generally at 30 in the aforesaid patent application to prevent opening of lid 16 when hazardous pressure conditions exist within the frying pot 14. For convenience, the latching mechanism shown at least in part herein will be referred to as the latching mechanism 30 in order to show correspondence to equivalent structure in the aforesaid patent application. Certain other structural elements shown in the aforesaid patent application will also be similarly referred to by like numerals in the present disclosure.
In order to complete description of structural portions of the pressure cooker directly operable with the safety interlock system 10, it is to be noted that the lid 16 of the frying pot 14 seals peripheral edges of the frying pot, which edges define the opening closed by the lid 16. A bar 18 is pivotally mounted to a rear exterior wall of the frying pot 14 in a conventional manner by means of spaced arcuate stanchions 20 and a mounting pin 22 received through the stanchions 20 and through mounting arms 24 extending from the bar 18. A spring 26 is mounted between the stanchions 20 and the bar 18 in a known manner to exert a force upwardly on the bar to cause upwardly pivoting movement of the bar 18 and thus opening of the lid on release of restraints to opening of the lid provided by the latching mechanism 30. The bar 18 is pivotally mounted to the lid 16 as is described in Ser. No. 298,481 to allow force to be exerted evenly over the lid 16 for effective sealing thereof.
Active portions of the safety interlock system 10 are seen to be mounted along upper surfaces of the bar 18, these active portions particularly comprising a pin 28 carried by a solenoid 32. The pin 28 is seen to correspond in structure and operation to the locking dowel 218 described in the aforesaid patent application, the pin 28 being constructed and usable according to the several embodiments thereof as indicated in the aforesaid patent application. The solenoid 32 is seen to be mounted to the bar 18 by means of a simple L-shaped mount 34 and is covered by cover 36 having an aperture 38 formed in a forward end thereof and through which solenoid arm 40 extends. While the solenoid arm 40 could be configured as having a length capable of functioning to include the functions of the pin 28, practical considerations typically dictate that the pin 28 be threaded at its anterior end to mate with a threaded recess formed in the distal end of the solenoid arm 40. The pin 28 thus extends toward the latching mechanism 30 and through an L-shaped pin guide 42. When the safety interlock system 10 is in the locked position, the distal end of the pin 28 engages one of the vertical slots 44 formed regularly in the exterior surface of hub 46 and radially about the periphery thereof. The slots 44 and the hub 46 of the present disclosure correspond to the slots 222 and the hub 100 of the disclosure of Ser. No. 298,481. When the distal end of the pin 28 is engaged with one of the slots 44, the latching mechanism 30 cannot be turned in order to release the lid 16 from a seated, sealed and latched position over the opening of the frying pot 14. According to the present invention, the pin 28 engages one of the slots 44 in the hub 46 when a sufficiently high pressure exists within the frying pot 14 to constitute a hazard or when power is discontinud to the system 10.
The solenoid 32 is preferably taken to be a pull-type DC solenoid valve which may preferably take the form of linear solenoid valve Model L12-A-M5-L-E4-208C-24 such as is manufactured by the G. W. Lisk Company and which is designed for continuous duty at 24 watts power. The preferred solenoid valve conveniently is provided with a 3/8 inch stroke, a 2 lb. pull and has a 4 ounce spring return. A pull-type solenoid is preferred according to the present invention in order that the conventional spring return within such a solenoid actually causes the pin 28 to be biased into locking engagement with the latching mechanism 30 on discontinuation of power to the solenoid 32 such as by operation of a pressure switch 48 which senses the build-up of pressure within the frying pot 14 to a predetermined level, such as one pound of pressure above atmospheric pressure. Essentially, electrical power acts to operate the solenoid 32 at all times when pressure within the frying pot 14 is either at atmospheric or at a level, such as below 8/10 pound of pressure, which allows safe operation of the latching mechanism 32 to open the lid 16. However, the existence of pressure conditions within the closed frying pot 14 which are at or above 1.0 pound of pressure, for example, causes the pressure switch 48 to discontinue power to the solenoid 32 and to thereby cause the spring portion of the conventional solenoid to direct the distal end of the pin 28 into locking engagement with the latching mechanism 30. As is seen in FIGS. 1 and 2, electrical leads 50 extending from the solenoid 32 to control box 52 are housed by tubing 54 which connect to the cover 36 and to the control box 52 by means of appropriate fittings 56.
An AC/DC rectifier is interposed in the circuitry between the solenoid 32 and the pressure switch 48. The rectifier thus converts the usual 240 volt AC current to 240 volt DC current so that a DC solenoid valve can be used as the solenoid 32. It is preferred to utilize a DC solenoid from the standpoint of practicality since conventional AC solenoid coils heat up more rapidly and operate at a higher temperature than corresponding DC powered solenoids. The useful life of the solenoid 32 is therefore increased and service failures are less likely when the solenoid 32 comprises a DC unit since the present system 10 is typically used on a nearly continuous basis. It is to be understood, however, that an AC solenoid can be used, though perhaps with reduced reliability, such use thereby eliminating the need for the rectifier 58.
The pressure switch 48 may conveniently be selected to compirse a Qualitrol Corporation Model 146 pressure switch. The switch 48 senses both pressure rise and fall and uses a normally closed terminal to open and close the linear solenoid 32. Pressure is seen to be transmitted to the diaphragm (not shown) of the pressure switch 48 through pressure tube 60 which may conveniently comprise a 1/4 inch outer diameter length of tubing which is connected to live steam within the frying pot 14 by means of an appropriate connection such as at the pressure gauge 62. It is to be understood that pressure connection between the pressure switch 48 and the interior of the frying pot 14 can be made in a variety of ways including direct connection into the frying pot or connection to any steam line brought to the frying pot 14 for any other purpose. A T-connection in the steam line leading to the pressure gauge 62 from the frying pot 14 can be utilized conveniently with one leg of the T connecting to the pressure tube 60 by means of appropriate fitting 66. Similar fittings 68 connect the pressure tube 60 to the control box 52 and to the pressure switch 48 in a conventional manner.
The pressure switch 48 normally allows completion of the electrical circuit which provides power to the solenoid 32, the solenoid 32 thus pulling the distal end of the pin 28 away from engagement with the latching mechanism 30. When power is off for any reason, including emergency conditions, the pin 28 is thus engaged with the latching mechanism 30 to prevent operation thereof. When the main power switch (not shown) is turned on during normal operation of the pressure cooker, the solenoid 32 pulls the pin 28 back from engagement with the latching mechanism 30, power always being required to pull the pin the required distance to be clear of the slots 44 in the hub 46. As indicated previously, discontinuation of the power to the system 10 either intentionally or in the event of a power failure or similar emergency, causes the pin 28 to move forwardly due to the bias of the spring (not shown) in the solenoid 32 such that the latching mechanism 32 becomes locked.
In normal operation, the main power switch (not shown) is activated and the usual timing mechanisms associated with the pressure cooker are set, including time and temperature settings. A frying basket (not shown) filled with a food which is to be fried is then placed in the frying pot 14 and the lid 16 is latched over the frying pot 14 in the manner described in the aforesaid patent application. During these operations, the solenoid 32 holds the pin 28 in an unlocked position out of engagement with the latching mechanism due to the fact that power is being supplied to the solenoid 32.
As the food product heats up within the frying pot 14, moisture is given off in the form of steam and pressure increases within the frying pot 14 past a predetermined value, such as one pound psig. The pressure rise within the frying pot 14 is experienced by one side of the diaphragm (not shown) of the pressure switch 48 since the pressure within the frying pot 14 is transmitted to the pressure switch 48 through the tube 60. At a predetermined pressure level, such as one pound of gauge pressure as noted, the pressure switch is "tripped" to close the power circuit to the rectifier 58 and thus to the solenoid 32 so that the spring function within the solenoid 32 pushes the pin 28 into the locked position such that one of the slots 44 in the hub 46 of the latching mechanism 30 is engaged either immediately or upon partial rotation of the latching mechanism 30 as is described in the aforesaid patent application. As long as the pin 28 is thus engaged with the latching mechanism 30, the lid 16 cannot be removed from sealing engagement with the opening of the frying pot 14. During the cooking operation, the internal pressure builds to an operational pressure of approximately 12 psig and, at the end of the timed cooking cycle, steam is discharged from the frying pot through a condensate stack (not shown) through conventional timers and steam solenoid valve discharge systems to thereby clear the frying pot 14 of accumulated steam pressure. When the pressure within the frying pot 14 reaches a pedetermined level, such as 0.8 psig, the pressure experienced by the pressure switch 48 once again causes power to be applied to the solenoid 32 thereby to pull the pin 28 out of engagement with the latching mechanism 30 such that the lid 16 can be removed from the frying pot 14.
The safety interlock system 10 of the present invention is thus seen to provide simple, inexpensive and wear-resistant structure capable of effective locking of a latching mechanism utilized to hold a lid over the opening of a frying pot such as commonly employed in a pressure cooker. The present system 10 is seen to be reliable in operation not only during normal conditions but also during conditions such as are experienced during power failures and the like due to the ability of the system 10 to function in a positive locking mode without the need for electrical power. While the system 10 has been explicitly described as detailed hereinabove, it is to be understood that the invention can be configured otherwise than as explicitly shown and described herein without departing from the intended scope of the invention and that the structure of the invention can be utilized in use environments other than the environment explicitly shown. Accordingly, the scope of the invention is seen to be defined by the recitations of the appended claims. | An improved pressure-activated interlock system for a pressure vessel such as a pressure fryer, the interlock system includes a safety lock which cooperates with a latching mechanism to prevent opening of the pressure vessel while potentially hazardous pressure levels exist within the vessel. The safety lock includes a pin and associated solenoid actuator mounted on an arm which both mounts the latching mechanism and also serves to lift the lid of the pressure vessel. The existence of pressure conditions of a given level within the pressure vessel causes the solenoid to force the pin into engagement with one of a plurality of spaced radial slots formed in a hub portion of the latching mechanism, thereby preventing operation of the latching mechanism and thus opening of the pressure vessel. The solenoid is actuated by means of a pressure switch which directly senses the pressure within the pressure vessel. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Ser. No. 61/434,862, filed Jan. 21, 2011, entitled, “SYSTEM FOR QUANTIFYING THE PRESENCE OF PHASE COUPLING USING THE BISPECTRUM,” U.S. Provisional Application Ser. No. 61/512,199, filed Jul. 27, 2011, entitled, “PHYSIOLOGICAL PARAMETER MONITORING FROM OPTICAL RECORDINGS WITH A MOBILE PHONE,” U.S. Provisional Application Ser. No. 61/434,856, filed Jan. 21, 2011, entitled, SYSTEM AND METHOD FOR THE DETECTION OF BLOOD VOLUME LOSS,” and U.S. Provisional Application Ser. No. 61/566,329, filed Dec. 2, 2011, entitled, “TIME-VARYING COHERENCE FUNCTION FOR ATRIAL FIBRILLATION DETECTION,” all of which are incorporated by reference herein in their entirety for all purposes.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This work was funded in part by the Office of Naval Research, Work Unit N00014-10-1-0640. The U.S. Government has certain rights in the invention.
BACKGROUND
[0003] These teachings relate generally to physiological parameter monitoring, and, more particularly, to physiological parameter monitoring with a mobile communication device.
[0004] There is a need for low-cost physiological monitoring solutions that are easy to use, accurate, and can be used in the home or in ambulatory situations. Smart phones are becoming more popular, more powerful and have a variety of sensors available to capture information from the outside world, process in real-time, and transfer information remotely using wireless communications. This makes them an ideal option as a ‘take-anywhere’ physiological monitor without the need for additional hardware, and their potential has been explored for many medical telemonitoring applications.
[0005] Optical video monitoring of the skin with a digital camera contains information related to the subtle color changes caused by the cardiac signal and can be seen to contain a pulsatile signal. Given illumination of the area with a white LED mobile phone flash, this type of imaging can be described as reflection photoplethysmographic (PPG) imaging. The dynamics of the HR signal that can be captured by PPG contain information that can be used to detect other physiological conditions.
[0006] Motion artifacts can affect the results of standard PPG. In the case of a mobile device and where there is no physical device ensuring a stable connection as is the case with pulse-oximeter clips or EKG electrodes, motion artifacts can be of more concern. There is a need for systems and methods for physiological monitoring with a mobile communication device that allow detection of motion artifacts.
BRIEF SUMMARY
[0007] The teachings described herein disclose systems and methods that enable physiological monitoring with a mobile communication device and that allow detection of motion artifacts so that the results reported are of acceptable quality are disclosed.
[0008] In one or more embodiments, the method of these teachings for physiological parameter monitoring includes providing a physiological indicator signal to a mobile communication device analyzing, using the mobile communications device, the physiological indicator signal to obtain measurements of one or more physiological parameters and detecting, using the mobile communications device, effects of motion artifacts in the measurements of the one or more physiological parameters and deciding whether to retain the measurements.
[0009] Other embodiments and instances of the method of these teachings are also disclosed.
[0010] In one or more embodiments of the system of these teachings, the system includes a physiological indicator signal sensing component (sensor) and a mobile communication device having an analysis component analyzing the physiological indicator signal to obtain measurements of one or more physiological parameters and a motion artifact detection component detecting effects of motion artifacts in the measurements of the one or more physiological parameters.
[0011] Other embodiments and instances of the system of these teachings are also disclosed.
[0012] Embodiments and instances of computer usable media having computer readable code embodied therein, where the computer readable code causes one or more processors to implement the embodiments of the method of these teachings are also disclosed.
[0013] For a better understanding of the present teachings, together with other and further objects thereof, reference is made to the accompanying drawings and detailed description and its scope will be pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a flowchart representation of one embodiment of the method of these teachings;
[0015] FIG. 1 a is a schematic flowchart representations of components of one embodiment of the method of these teachings;
[0016] FIG. 1 b is a schematic flowchart representations of components of another embodiment of the method of these teachings;
[0017] FIGS. 2 a - 2 c are schematic graphical representations of results for one exemplary embodiment of the method of these teachings;
[0018] FIGS. 3 a - 3 c are schematic graphical representations of results for another exemplary embodiment of the method of these teachings;
[0019] FIGS. 4 a - 4 b are schematic graphical representations of results for yet another exemplary embodiment of the method of these teachings;
[0020] FIG. 5 illustrates a schematic graphical representation of a resultant Time-Varying Coherence Function (TVCF) in a further exemplary embodiment of the method of these teachings;
[0021] FIGS. 6 a and 6 b are schematic graphical representations of the TVCF at different frequencies in the further exemplary embodiment of the method of these teachings;
[0022] FIGS. 7 a - 7 c illustrate schematic graphical representations of true AF annotation and the values of frequency variations (FV) for different databases in the further exemplary embodiment of the method of these teachings; and
[0023] FIG. 8 represents a schematic block diagram representation of one embodiment of the system of these teachings.
DETAILED DESCRIPTION
[0024] The following detailed description is of the best currently contemplated modes of carrying out these teachings. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of these teachings, since the scope of these teachings is best defined by the appended claims. Although the teachings have been described with respect to various embodiments, it should be realized these teachings are also capable of a wide variety of further and other embodiments within the spirit and scope of the appended claims.
[0025] As used herein, the singular forms “a,”“an,” and “the” include the plural reference unless the context clearly dictates otherwise.
[0026] Except where otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.”
[0027] To assist in the understanding of the present teachings the following definitions are presented.
[0028] A “mobile communication device,” as used herein, refers to a device capable of executing applications, and which is portable. In one instance, the mobile communication device has one or more processors and memory capability. Examples of mobile communication devices, these teachings not being limited to only these examples, include mobile phones, smart mobile phones, digital personal assistants, etc.
[0029] A “physiological indicator signal,” as used herein, refers to a signal that can be used to obtain measurements of one or more physiological parameters. Examples of physiological indicator signals, these teachings not being limited only to those examples, include photoplethysmograph (PPG) signals, electrocardiogram (EKG) signals and color video images obtained from a portion of a subject's body (for example, but not limited to, obtained using the camera in a mobile communication device), which behave as reflection PPG images.
[0030] “Volatility,” as used herein, refers to a measure of the probability of obtaining an extreme value in the future , such as measured by kurtosis and other statistical measures.
[0031] “Detrending,” as used herein, refers to the process of finding a best polynomial fit to a time series and subtracting that best polynomial fit from the time series.
[0032] “SpO2,” as used herein, refers to a measurement of the amount of oxygen being carried by the red blood cell in the blood. SpO2 is usually given in as a percentage and measures oxygen saturation.
[0033] In one or more embodiments, the method of these teachings for physiological parameter monitoring includes providing a physiological indicator signal to a mobile communication device (step 5 , FIG. 1 ), analyzing, using the mobile communications device, the physiological indicator signal to obtain measurements of one or more physiological parameters (step 10 , FIG. 1 ) and detecting, using the mobile communications device, effects of motion artifacts in the measurements of the one or more physiological parameters and deciding whether to retain the measurements (step 12 , FIG. 1 ).
[0034] The physiological indicator signal can, in one instance, be provided by placing a portion of a subject's body over an objective lens of a camera in a mobile communication device and obtaining video images of the portion of the subject's body. In another instance, the physiological indicator signal can be provided by a physiological monitoring sensor, for example, an external photoplethysmographic (PPG) sensor or an external electrocardiogram sensor. It should be noted that other manners of providing the physiological indicator signal are within the scope of these teachings.
[0035] Motion Artifacts
[0036] One embodiment of the method for detecting effects of motion artifacts in the measurements of the one or more physiological parameters and deciding whether to retain the measurements is disclosed hereinbelow. It should be noted that other embodiments are within the scope of these teachings.
[0037] In the embodiment shown in FIG. 1 a , the method for detecting effects of motion artifacts includes preprocessing a segment of a signal ( 15 , FIG. 1 a ) from a physiological measurement ( 29 , FIG. 1 a ), obtaining a value of one or more indicators of volatility for the preprocessed segment ( 25 , FIG. 1 a ) and determining from comparison of the value of the one or more indicators of volatility with a predetermined threshold whether or not noise/motion artifacts are not present. If noise/motion artifacts are not present, the segment is included in calculations quantities of interest ( 40 , FIG. 1 a ) and the method proceeds to another segment ( 50 , FIG. 1 a ), if another segment is available. If noise/motion artifacts are present, for most physiological parameters, the segment is discarded ( 45 , FIG. 1 a ) and the method proceeds to another segment ( 50 , FIG. 1 a ), if another segment is available. For the measurement of an indication of blood loss, as shown in FIG. 1 b , a time-frequency spectrum analysis is performed for the preprocessed segment ( 30 , FIG. 1 b ) and a predetermined measure of the time-frequency spectrum analysis is compared to a predetermined measure's threshold ( 35 , FIG. 1 b ). If the predetermined measure is within limits determined by the predetermined measure's threshold, the segment is included in calculations quantities of interest ( 40 , FIG. 1 b ) and the method proceeds to another segment, if another segment is available ( 50 , FIG. 1 b ). If the predetermined measure is not within the limits determined by the predetermined measure's threshold, the segment is discarded ( 45 , FIG. 1 b ) and the method proceeds to another segment ( 50 , FIG. 1 b ), if another segment is available.
[0038] In one instance, the measure of volatility used in the above disclosed embodiment includes kurtosis. In another instance, the measure of volatility includes Shannon entropy. In a further instance, the measure of volatility uses both kurtosis and Shannon entropy.
[0039] An exemplary embodiment of the application of the method for detecting motion artifacts is described herein below in order to further elucidate these teachings. However it should be noted that these teachings are not limited to only that exemplary embodiments.
[0040] Experimental Protocol for One Exemplary Embodiment
[0041] The algorithm has been tested on PPG signals obtained from two distinct scenarios as follows.
[0042] 1. Involuntary movements: Multi-site PPG signals recorded from 10 healthy volunteers under supine resting conditions for 5 to 20 minutes in clinical settings were used for our analysis. The data analyzed were a part of simulated blood loss experiments which consisted of baseline and lower body negative pressure application where the data from only the former condition was used for this study. Three identical reflective infrared PPG-probes (MLT1020; ADI Instruments, CO Springs, Colo., USA) were placed at the finger, forehead and ear. While the finger and ear PPG probes were attached with a clip, the forehead probe was securely covered by a clear dressing. The PPG signals were recorded at 100 Hz with a Powerlab/16 SPdata acquisition system equipped with a Quad Bridge Amp (ML795 & ML112; ADI Instruments) and a high-pass filter cut-off of 0.01 Hz. The subjects were not restricted from making any sort of movements during the recording procedure.
[0043] 2. Voluntary movements: Finger-PPG signals were obtained from 14 healthy volunteers in an upright sitting posture using an infrared reflection type PPG transducer (TSD200) and a biopotential amplifier (PPG100) with a gain of 100 and cut-off frequencies of 0.05-10 Hz. The MP100 (BIOPAC Systems Inc., Calif., USA) was used to acquire finger PPG signals at 100 Hz. After baseline recording for 5 minutes without any movements (i.e. clean data), motion artifacts were induced in the PPG data by left-right movements of the index finger with the pulse oximeter on it. The subjects were directed to produce the motions for time intervals that determined the percentage of noise within each 1 minute segment; varying from 10 to 50%. For example, if a subject was instructed to make left-right movements for 6seconds, that segment of data would contain 10% noise. Such controlled movements were carried out 5 times for each level of noise. In this protocol, we used the left-right movement of the index finger having the PPG clamp to induce movement artifacts since left-right movement was perpendicular to the plane of the PPG sensor orientation and thus generated significant noise as compared to up-down or arbitrary movements of the finger. The recorded PPG signals from both protocols were analyzed offline using Matlab®.
[0044] B. Data Preprocessing:
[0045] The PPG data were partitioned into 60s segments and shifted every 10s for the entire data. Each 60s PPG segment was subjected to a finite impulse response (FIR) band pass filter of order 64 with cut-off frequencies of 0.1 Hz and 10 Hz. To account for the time-dependent low-frequency trends associated with the PPG signal and depending on the type of data analysis, either a low- or high-order polynomial detrending was used. For the purpose of artifact detection, we used in some cases as high as the 32nd-order polynomial fit to eliminate nonstationary dynamics in the PPG signal. The use of a high-order polynomial detrend is important to an effective classification between clean and artifact-containing signals. For the time-frequency-spectral analysis during the second stage to determine usable data, a standard 2nd order polynomial detrend was used on the original PPG data (not on the data with a high-order polynomial detrend). Following detrend with either a low- or high-order polynomial fit, the PPG signal was zero-meaned. Before a computational analysis is conducted, the PPG waveforms in each data segment are visually examined and classified them into clean vs. corrupted segments. Any sort of disruption in the pulse characteristics was labeled as corrupted segments. This was done in order to later determine the accuracy of the method.
[0046] C. Computational Measures for Artifact Detection
[0047] Following the preprocessing of each PPG data segment, our approach for the detection of artifacts involves the computation of the following two parameters.
[0048] Kurtosis: Kurtosis is a statistical measure used to describe the distribution of observed data around the mean. It represents a heavy tail and peakedness or a light tail and flatness of a distribution relative to the normal distribution. The kurtosis of a normal distribution is 3. Distributions that are more outlier-prone than the normal distribution have kurtosis greater than 3; distributions that are less outlier-prone have kurtosis less than 3. The kurtosis is defined as:
[0000]
k
=
E
(
x
-
μ
)
4
σ
4
(
1
)
[0000] Where μ is the mean of χ, σ is the standard deviation of χ, and E(t) represents the expected value of the quantity t.
[0049] Shannon entropy: SE quantifies how much the probability density function (PDF) of the signal is different from a uniform distribution and thus provides a quantitative measure of the uncertainty present in the signal. SE can be calculated as
[0000]
SE
=
-
∑
i
=
1
k
p
(
i
)
*
log
(
p
(
i
)
)
log
(
1
k
)
(
2
)
[0000] Where i represents the bin number, and p(i) is the probability distribution of the signal amplitude. Presently, 16 bins (κ=16) have been used to obtain a reasonably accurate measure of SE.
[0050] D. Statistical analysis of computational measures:
[0051] The nonparametric Mann Whitney test was conducted on data from the involuntary motion protocol to find the significance levels (p<0.05) for the SE and kurtosis measures between clean vs. corrupted PPG segments. Meanwhile, the nonparametric Kruskal-Wallis test with Dunn's multiple comparison post test was conducted on data from the voluntary motion protocol to find the significance (p<0.05) between clean vs. noise-corrupted PPG segments for the two measures.
[0052] E. Detection of motion/noise artifacts:
[0053] By varying kurtosis values from 0 to 10 with an increment of 0.1, and SE values from 0.5 to 1.0 with an increment of 0.01, receiver-operator characteristic (ROC) analysis were conducted for the population of SE and kurtosis values obtained from the respective pool of clean and corrupted PPG segments of both protocols: The substantially optimal threshold values for kurtosis and SE that produced the substantially optimal sensitivity and specificity for the detection of artifacts. (see, for example, S. H. Park et. al., Receiver Operating Characteristic (ROC) Curve: Practical Review for Radiologists, Korean J Radiol. 2004 January-March; 5(1): 11-18, which is Incorporated by reference herein is entirety for all purposes) where evaluated.
[0054] The decision rules for the detection of artifacts were formulated as follows:
[0000]
DK
i
-
{
1
if
K
i
≤
K
Th
0
if
K
i
>
K
Th
(
3
)
[0000] where DK i refers to the decision for artifact detection based on K i , kurtosis for the i th segment. ‘1’ represents clean data, whereas ‘0’ represents corrupted data. K Th refers to the Kurtosis threshold.
[0000]
DS
i
-
{
1
if
SE
i
≥
SE
Th
0
if
SE
i
<
SE
Th
(
4
)
[0000] where DS i refers to the decision for artifact detection based on SE i , SE for the i th segment. ‘1’ represents clean data whereas ‘0’ represents corrupted data. SE Th refers to the SE threshold.
[0055] The fusion of kurtosis and SE metrics with their substantially optimal threshold values for the artifact detection was further consider and the sensitivity and specificity for the fusion of these two metrics was quantified. The decision rule for the detection of artifacts using a fusion of kurtosis and SE is:
[0000]
FD
i
-
{
1
if
DK
i
+
DS
i
=
2
0
if
DK
i
+
DS
i
≠
2
(
5
)
[0000] where FD i refers to the fusion decision for artifact detection based on both DK i and DS i for the i th segment. ‘1’ represents clean data whereas ‘0’ represents corrupted data.
[0056] Time-frequency spectral analysis for the assessment of severity of noise
[0057] In the second stage of this embodiment of the motion/Noise Artifact algorithm, where blood loss is being detected, how severe the noise must be to affect the dynamics of the signal in the HR frequency range is assessed (shown in FIG. 1 b ). Specifically, this second stage determines if some of the segments that were deemed to contain artifacts can be used for noninvasive blood loss detection, as these data may not be heavily contaminated.
[0058] This step first requires the computation of time-frequency analysis so that the amplitude modulations at each time point within the heart rate band can be obtained. This extracted amplitude modulation information is subsequently used to determine the state of usable data as detailed in the proceeding section. A time-frequency method known as the variable frequency complex demodulation method (VFCDM) to be described hereafter is used because it has been shown to provide one of the highest time-frequency resolutions.
[0059] VFCDM Analysis: The development of the VFCDM algorithm has been previously disclosed in K. H. Chon, S. Dash, and K. Ju, “Estimation of respiratory rate from photoplethysmogram data using time-frequency spectral estimation,” IEEE Trans Biomed Eng, vol. 56, no. 8, pp. 2054-63, August, 2009 and in U.S. Patent Application Publication 20080287815, published on Nov. 20, 2008, corresponding to U.S. patent application Ser. No. 11/803,770, filed on May 16, 2007, both of which are incorporated by reference herein in their entirety for all purposes. Thus the VFCDM algorithm will be only briefly summarized hereinbelow.
[0060] Consider a sinusoidal signal x(t) to be a narrow band oscillation with a center frequency f0, instantaneous amplitude A(t), phase Φ(t), and the direct current component dc(t):
[0000] x ( t )= dc ( t )+ A ( t )cos (2πƒ 0 t+Φ( t ) (6)
[0061] For a given center frequency, the instantaneous amplitude information A(t) and phase information Φ(t) can be extracted by multiplying (6) by e −j2πƒ0 0 (t) , which results in the following:
[0000]
z
(
t
)
=
x
(
t
)
-
j2π
f
o
t
=
c
(
t
)
-
j2π
f
o
t
+
(
A
(
t
)
2
)
jφ
(
t
)
+
(
A
(
t
)
2
)
-
j
(
4
π
f
o
t
+
φ
(
t
)
)
(
7
)
[0062] A leftward shift by e −j2πƒ 0 (t) results in moving the center frequency f0 to zero frequency in the spectrum of z(t). If z(t) in (7) is subjected to an ideal low-pass filter (LPF) with a cut-off frequency f 1 <f a , then the filtered signal z ip (t) will contain only the components of interest and the following can be extracted:
[0000]
z
lp
(
t
)
=
A
(
t
)
2
j
φ
(
t
)
(
8
)
A
(
t
)
=
2
z
lp
(
t
)
(
9
)
φ
(
t
)
=
tan
-
1
imag
(
z
lp
(
t
)
)
real
(
z
lp
(
t
)
)
(
10
)
[0063] The method can easily be extended to the variable frequency case, where the modulating frequency is expressed as ∫ 0 t 2πƒ(τ)dτ and the negative exponential term used for the demodulation is e −j∫ 0 τ 2πƒ(τ)dτ. The instantaneous frequency can be obtained using the familiar differentiation of the phase information as follows:
[0000]
f
(
t
)
=
f
0
+
1
2
π
φ
(
t
)
(
t
)
(
11
)
[0064] Thus, the VFCDM method involves a two-step procedure. At first, the fixed frequency complex demodulation technique identifies the signal's dominant frequencies, shifts each dominant frequency to a center frequency, and applies a low-pass filter (LPF) to each of the center frequencies. The LPF has a cutoff frequency less than that of the original center frequency and is applied to each dominant frequency. This generates a series of band-limited signals. The instantaneous amplitude, phase and frequency information are obtained for each band-limited signal using the Hilbert transform and are combined to generate a time-frequency series (TFS). Finally, the second step of the VFCDM method is to select only the dominant frequencies and produce a high-resolution TFS.
[0065] Once the TFS of the PPG signal is obtained via the VFCDM method, the largest instantaneous amplitude at each time point within the HR band (HR±0.2 Hz) of the TFS of the VFCDM are extracted as the so-called AMHR components of the PPG that reflect the time varying amplitude modulation (AM) of the HR frequency. The initial and final 5s of the TFS were not considered for the AMHR extraction because time frequency series have an inherent end effect that could produce false variability of the spectral power. The median value of the AMHR components was evaluated for each corrupted PPG segment.
[0066] Determination of usable PPG segments corrupted with insignificant artifacts:
[0067] The AMHR median values were computed separately for clean PPG segments of each probe site for involuntary artifacts as well as for the voluntary artifact protocols as described above. The mean±2*SD of the AMHR median population were determined as their respective 95% statistical limits for each clean PPG data set. If the AMHR median value of the corrupted PPG segment lies within the statistical limits of the clean data, the respective corrupted PPG segment was considered as usable data; otherwise it was rejected. Thus, the model of our algorithm outlined in FIG. 1 has been designed to function in two separate stages for the detection and quantification of usable data among those that contain artifacts in PPG signals. Referring to FIG. 1 a , a segment of a signal ( 15 , FIG. 1 ) from PPG is preprocessed (filtered) ( 55 , FIG. 1 a ), one or more indicators of volatility for the preprocessed segment are evaluated ( 60 , FIG. 1 a ) to determine from comparison of the value of the one or more indicators of volatility with a predetermined threshold whether or not noise/motion artifacts are not present. If noise/motion artifacts are not present, the segment is included in calculations quantities of interest ( 65 , FIG. 1 ) and the method proceeds to another segment, if another segment is available. If noise/motion artifacts are present, a time-frequency spectrum analysis is performed for the preprocessed segment and a predetermined measure of the time-frequency spectrum analysis, AMHR, is compared to a predetermined measure's threshold, the mean±2*Standard deviations (SD) of the AMHR median population of a clean sample. If the predetermined measure is within limits determined by the predetermined measure's threshold, the segment is included in calculations quantities of interest and the method proceeds to another segment, if another segment is available). If the predetermined measure is not within the limits determined by the predetermined measure's threshold, the segment is discarded and the method proceeds to another segment, if another segment is available.
[0068] Heart Rate And Heart Rate Variability Detection
[0069] In one instance, the physiological measurements are heart rate and heart rate variability. In one embodiment, the method of these teachings for obtaining measurements of heart rate and heart rate variability includes determining beats for the physiological indicator signal (examples of beat detection algorithm, these teachings not be limited to those examples, can be found in Beat Detection Algorithms, available at http://www.flipcode.com/misc/BeatDetectionAlgorithms.pdf and accessed on Jan. 17, 2012), determining beat to beat intervals and applying a cubic spline algorithm to obtain a substantially continuous beat to beat interval signal indicative of heart rate.
[0070] The method for detection of beat to beat variability disclosed in United States Patent Application No. 20110166466, entitled RR INTERVAL MONITORING METHOD AND BLOOD PRESSURE CUFF UTILIZING SAME, published on Jul. 7, 2011, which is incorporated by reference herein is entirety for all purposes, could be applied. Also the methods for detection of the autonomous system imbalance disclosed in United States Patent Application 20090318983, entitled Method And Apparatus For Detection And Treatment Of Autonomic System Imbalance, published on Dec. 24, 2009, which is Incorporated by reference herein is entirety for all purposes, could be applied.
[0071] In another instance, the physiological measurement is respiratory rate. One embodiment of the method for obtaining measurements of respiratory rate includes obtaining time-frequency spectrum of the physiological indicator signal utilizing variable frequency complex demodulation (VFCDM) and obtaining respiratory rates by extracting a frequency component that has a largest amplitude for each time point at a heart rate frequency band.
[0072] An exemplary embodiment of the measurement of heart rate and heart rate variability and respiratory rate is presented hereinbelow in order to further elucidate these teachings. It should be noted that these teachings are not limited to the exemplary embodiment.
[0073] In order to compare the exemplary embodiment of the present teachings to conventional methods, experiments were performed to measure the heart rate, heart rate variability and respiratory rate using conventional techniques. Electrocardiogram (EKG) recordings were made with an HP 78354A acquisition system using the standard 5-lead electrode configuration. A respiration belt was attached around the subject's chest to monitor breathing rate (Respitrace Systems, Ambulatory Monitoring Inc.). Respiratory and EKG recordings were saved using LabChart software (ADInstruments) at a sampling rate of 400 Hz.
[0074] Data were recorded during spontaneous breathing for a single subject. Data collection was initiated as follows: (1) initiate mobile phone video recording, (2) start recordings of EKG and respiration trace 10 seconds after initiation of mobile phone recording, and (3) set mobile phone down and place subject's left index finger over camera lens. This procedure allowed for alignment of data files to within 1 second.
[0075] Metronome breathing experiments were performed on a single subject with rates set at 0.2, 0.3, and 0.4 Hz (12, 18, and 24 Beats per Minute (BPM)). The subject was asked to inhale with each beat of the metronome. Metronome recordings were made for 2 minutes for each section.
[0076] For the measurements using the exemplary embodiment of these teachings, color changes of the finger were recorded using a Motorola Droid® (Motorola Mobility, Inc.) mobile phone. The palmar side of the left index finger was placed over the camera lens with the flash turned on. Subjects were instructed to rest their finger on the camera lens without pressing down with additional force, and to keep their finger still to reduce any motion artifacts. Videos were recorded with 720×480 pixel resolution at a sampling rate of 24.99 fps in 0.3 gpp file format. The 0.3 gpp videos were converted to Audio-Video Interleave (AVI) format at 720×480 pixel resolution and 25 fps using Pazera Free 3 gp to AVI Converter 1.3 (http://www.pazera-software.com/). All further analysis was performed on the AVI videos in Matlab R2010b (The Mathworks Inc.)
[0077] For experiments assessing HR, heart rate variability (HRV), and respiration rate, only the green band from the video recordings was used. A 50×50 pixel average of a region on the video signal at each frame was made for the green band. This signal is from herein referred to as GREEN.
[0078] R-wave peak detection was performed for the EKG signal using a custom peak detection algorithm. Beats were detected for the GREEN signal using a conventional algorithm. Beat-beat intervals were computed, and cubic splined to 4 Hz to obtain the continuous HR for each signal (HREKG and HRGREEN). The power spectral density (PSD) of HR was computed using Welch periodogram method.
[0079] A section 105 of an exemplary GREEN signal obtained during spontaneous breathing is shown in FIG. 2 a . The pulse signal is similar to a traditional PPG signal obtained from a pulse-oximeter. Peak detection was performed to identify the HR signal, shown in FIG. 2 b along with that obtained from an EKG after R-wave peak detection. The mean±SD was 92.2±5.3 for HREKG and 92.3±5.9 for HRGREEN.
[0080] The dynamics of the HR signals-HRGREEN 110 , HREKG 120 shown in FIG. 2 b were assessed by frequency analysis ( FIG. 2 c ). The dominant peak on both signals is seen to be at a low frequency<0.1 Hz. A second peak is seen on both signals in the sympathetic range (0.04-0.15 Hz), and a third peak at approximately 0.2 Hz is representative of the respiration rate. Additional high frequency components are seen in HRGREEN 112 compared to HREKG, possibly from the suboptimal low sampling frequency of the mobile phone recording.
[0081] Respiration Rate Detection
[0082] Frequency modulation (FM) and amplitude modulation (AM) sequences were extracted as described in K. H. Chon, S. Dash, and K. Ju, “Estimation of respiratory rate from photoplethysmogram data using time-frequency spectral estimation,” IEEE Trans Biomed Eng, vol. 56, no. 8, pp. 2054-63, August, 2009 and in U.S. Patent Application Publication 20080287815, published on Nov. 20, 2008, corresponding to U.S. patent application Ser. No. 11/803,770, filed on May 16, 2007, both of which are incorporated by reference herein in their entirety for all purposes, and used to estimate the breathing rate ( FIGS. 3 a & b ). Breathing rates were confirmed by taking the PSD of the respiration trace during 3 periods of metronome breathing recorded with the metronome set at 0.2, 0.3, and 0.4 Hz. Breathing rates from the respiration trace and GREEN signal using the FM sequence were estimated at the three metronome rates as 0.18 and 0.16, 0.30 and 0.32, and 0.40 and 0.38 Hz, respectively. The PSDs of the FM sequence 210 , 220 , 232 and respiration trace 212 , 222 , 230 for the three breathing rates are shown in FIG. 3 c.
[0083] Oxygen Saturation Detection
[0084] In yet another instance, the physiological measurement is a measure of oxygen saturation. In one embodiment, the physiological indicator signal is acquired by placing a portion of a subject's body over an objective lens of a camera in a mobile communication device and obtaining video images of the portion of the subject's body. In that embodiment, the method of these teachings for obtaining a measure of oxygen saturation includes obtaining an average intensity of a red component and a blue component of the video images of the portion of the subject's body, the average intensity of the red component and the average intensity of the blue component constituting DCRED and DCBLUE respectively, obtaining a standard deviation of the red component and the blue component, the standard deviation of the red component and the blue component constituting ACRED and ACBLUE respectively, and obtaining the measure of oxygen saturation (SpO2) by
[0000]
Sp
O
2
=
A
-
B
A
C
RED
D
C
RED
A
C
BLUE
D
C
BLUE
.
[0085] An exemplary embodiment of the measure of oxygen saturation is presented hereinbelow in order to further elucidate these teachings. It should be noted that these teachings are not limited to the exemplary embodiment.
[0086] In order to compare the exemplary embodiment of the present teachings to conventional methods, experiments were performed to measure oxygen saturation.
[0087] Breath holding experiments were performed to assess the impact of reduced oxygen saturation on the optical recordings on two subjects. A commercial reflectance pulse-oximeter (Radical SETTM, Masimo) was placed on the left ring finger to record 1 sec measurements of SpO2. The mobile phone camera lens was placed underneath the subjects' left index fingertip. A black cloth was placed around the finger on the camera lens to isolate the sensor from light emanating from the commercial pulse-oximeter. The data files were aligned by starting the data logging of the pulse-oximeter by verbal command after the mobile phone recording started, and using the audio file to determine the initiation time point.
[0088] Subjects were asked to breathe normally for approximately 30 seconds, exhale, and then to hold their breath till they felt discomfort. Two consecutive breath holding periods were recorded for each subject.
[0089] Oxygen Saturation Monitoring
[0090] The ratio of RED and BLUE in the equation for SpO provided hereinabove was computed and the A and B parameters were estimated for each subject using the commercial pulse-oximeter SpO2 values as a reference. For the subject shown in FIG. 4 a , A and B in
[0000]
Sp
O
2
=
A
-
B
A
C
RED
D
C
RED
A
C
BLUE
D
C
BLUE
[0000] and B in were determined to be 154.5 and 220.3, respectively, and for the subject in FIG. 4 b , A and B were determined to be 155.7 and 265.5. (In FIGS. 4 a and 4 b , measurements from the pulse oxymeter are labeled 310 , 312 , while measurements from these teachings are labeled 320 , 322 . It can be observed in FIGS. 4 a , 4 b that SpO 2 decreases monitored with the commercial pulse-oximeter appear to cause decreases in our computed SpO 2 value obtained from the mobile phone recording. For the subject in FIG. 4 a , a minimum SpO 2 level of 84% was recorded from the commercial pulse-oximeter and a minimum of 81% was computed with
[0000]
Sp
O
2
=
A
-
B
A
C
RED
D
C
RED
A
C
BLUE
D
C
BLUE
.
[0091] It should be noted that, although offline analysis we performed in the above exemplary embodiments, given the current processing power available in mobile phones (currently 1 GHz dual-core processors available), performing the analysis directly on a mobile phone is within the scope of these teachings.
[0092] Blood Loss Detection
[0093] In a further instance, the physiological measurement is a measure of blood loss. One embodiment of the method for obtaining a measure of blood loss includes obtaining time-frequency spectrum of the physiological indicator signal utilizing variable frequency complex demodulation (VFCDM), obtaining the amplitude modulation (AM) series from a set of the largest instantaneous amplitude at each time sample within the heart rate frequency band of the time-frequency spectrum and determining whether the amplitude modulation decreases, a decrease in the amplitude modulation indicating blood volume loss in the subject.
[0094] An exemplary embodiment of the method for obtaining a measure of blood loss is disclosed in U.S. Provisional Application Ser. No. 61/434,856, filed Jan. 21, 2011, entitled, SYSTEM AND METHOD FOR THE DETECTION OF BLOOD VOLUME LOSS” and in Nandakumar Selvaraj, Christopher G. Scully, Kirk H. Shelley, David G. Silverman, and Ki H. Chon, Early Detection of Spontaneous Blood Loss using Amplitude Modulation of Photoplethysmogram, 33rd Annual International Conference of the IEEE EMBS Boston, Mass. USA, Aug. 30-Sep. 3, 2011, both of which are incorporated by reference herein in their entirety for all purposes.
[0095] Other embodiments of the method for obtaining a measure of blood loss are disclosed in WIPO International Publication No. WO 2011/050066 A2, entitled “Apparatus And Method For Respiratory Rate Detection And Early Detection Of Blood Loss Volume,” published on Apr. 28, 2011, which is incorporated by reference herein in its entirety for all purposes.
[0096] Atrial Fibrillation Detection
[0097] In a further instance, the physiological measurement is a measure of atrial fibrillation. One embodiment of the method for obtaining a measure of atrial fibrillation includes obtaining a time-varying coherence function by multiplying two time-varying transfer functions (TVFTs), the two time-varying transfer functions obtained using two adjacent data segments with one data segment as input signal and the other data segment as output to produce the first TVTF, the second TVTF is produced by reversing the input and output signals and determining whether the time-varying coherence function (TVCF) is less than a predetermined quantity. In another embodiment, determining whether the time-varying coherence function is less than the predetermined quantity includes obtaining one or more indicators of atrial fibrillation and determining whether the one or more indicators of atrial fibrillation exceed predetermined thresholds. In one instance, the one or more indicators of atrial fibrillation include a variance of the time-varying coherence function. In another instance, the one or more indicators of atrial fibrillation also include Shannon entropy. In yet another instance, the predetermined thresholds are determined using receiver operator characteristic (ROC) analysis.
[0098] In the embodiment of the method for obtaining a measure of atrial fibrillation disclosed hereinabove, the TVCF is estimated by the multiplication of two time-varying transfer functions (TVTFs). The two TVTFs are obtained using two adjacent data segments with one data segment as the input signal and the other data segment as the output to produce the first TVTF; the second TVTF is produced by reversing the input and output signals. It has been found that the resultant TVCF between two adjacent normal sinus rhythm segments show high coherence values (near 1) throughout the entire frequency range. However, if either or both segments partially or fully contain AF, the resultant TVCF is significantly lower than 1. When TVCF was combined with Shannon entropy (SE), even more accurate AF detection rate of 97.9% are obtained for the MIT-BIH Atrial Fibrillation (AF) database (n=23) with 128 beat segments.
[0099] In the embodiment disclosed herein above, the TVCF is obtained by the multiplication of the two time-varying transfer functions. To demonstrate the use of the TVTF in obtaining the TVCF, the TVCF is first defined via the nonparametric time-frequency spectra as
[0000]
γ
(
t
,
f
)
4
=
S
xy
(
t
,
f
)
2
S
xx
(
t
,
f
)
S
yy
(
t
,
f
)
S
yx
(
t
,
f
)
2
S
yy
(
t
,
f
)
S
xx
(
t
,
f
)
(
12
)
[0000] where S xy (t,ƒ) and S xy (t,ƒ) represent the time-frequency cross-spectrum, and S xx (t,ƒ) and S yy (t,ƒ) represent the auto spectra of the two signals x and y, respectively. Specifically, the first term in Eq. (12) is the coherence function when x is considered as the input and y as the output. Similarly, the second term in Eq. (12) is the coherence function when y is considered as the input and x as the output. For a linear time varying (TV) system with x as the input and y as the output, the TVTF in terms of time-frequency spectra can be obtained as
[0000]
H
x
->
y
(
t
,
f
)
=
S
xy
(
t
,
f
)
S
xx
(
t
,
f
)
(
13
)
[0000] where H x→y (t,ƒ) is the TVTF from the input x to the output y signal. Similarly, for a linear TV system with y as the input and x as the output, the TVTF can be obtained as
[0000]
H
y
->
x
(
t
,
f
)
=
S
yx
(
t
,
f
)
S
yy
(
t
,
f
)
(
14
)
[0100] Thus, the time-varying magnitude |γ(t,ƒ)| 2 is obtained by multiplying the two transfer functions,
[0000] |H χ→ (t,ƒ)·H y→χ (t,ƒ)· (15)
[0101] Given the relationship of (15), a high resolution TVCF can be obtained from ARMA models:
[0000]
y
(
n
)
=
-
∑
i
=
1
P
2
a
(
n
,
i
)
y
(
n
-
i
)
+
∑
j
=
0
Q
2
b
(
n
,
j
)
x
(
n
-
j
)
(
16
-
1
)
x
(
n
)
=
-
∑
i
=
1
P
2
α
(
n
,
i
)
x
(
n
-
i
)
+
∑
j
=
0
Q
2
β
(
n
,
j
)
y
(
n
-
j
)
(
16
-
2
)
[0000] where (16-1) represents y(n) as the output and x(n) as the input. Similarly, (16-2) represents x(n) as the output and y(n) as the input. Given the ARMA models of (16), the two transfer functions of (15) can be obtained as
[0000]
H
x
->
y
(
n
,
j
w
)
=
B
(
n
,
j
w
)
A
(
n
,
j
w
)
=
∑
i
=
0
Q
1
b
(
n
,
j
)
-
j
w
1
+
∑
i
=
1
P
1
a
(
n
,
i
)
-
j
w
H
y
->
x
(
n
,
j
w
)
=
β
(
n
,
j
w
)
α
(
n
,
j
w
)
=
∑
i
=
0
Q
2
β
(
n
,
j
)
-
j
w
1
+
∑
i
=
1
P
2
a
(
n
,
i
)
-
j
w
(
17
)
[0102] Finally, the TVCF can be obtained by multiplying the two transfer functions as described in (17). For the parameter estimation, the time-varying optimal parameter search (TVOPS) criterion can be used, which has been shown to be accurate when applied to many diverse physiological signals. For the physiological signals considered, the TVOPS has been shown to be more accurate than the AIC, minimum description length (MDL) and the fast orthogonal search criterion. For TVOPS, time-varying coefficients are expanded onto a set of basis functions. It has been previously demonstrated that Legendre polynomials are a good choice for capturing dynamics that are smoothly changing with time.
[0103] AF Detection: Variance of TVCF
[0104] For AF detection, two adjacent beat segments with the length denoted as seg has been formulated using the following ARMA models:
[0000]
S
i
+
1
:
i
+
seg
(
n
)
=
-
∑
i
=
1
P
2
a
(
n
,
i
)
S
i
+
1
:
i
+
seg
(
n
-
i
)
+
∑
j
=
0
Q
2
b
(
n
,
j
)
S
i
+
seg
+
1
:
i
+
2
:
seg
(
n
-
j
)
S
i
+
seg
+
1
:
i
+
2
:
seg
(
n
)
=
-
∑
i
=
1
P
2
α
(
n
,
i
)
S
i
+
seg
+
1
:
i
+
2
:
seg
(
n
-
i
)
+
∑
j
=
0
Q
2
β
(
n
,
j
)
S
i
+
1
:
i
+
seg
(
n
-
j
)
(
18
)
[0000] where S i+1:i+seg (n) and S i+seg+1:i+2seg (n) are two adjacent RR interval time series from the (i+1) th to the (i+seg) th and from the (i+seg+1) th to the (i+2·seg) th , respectively. By substituting (18) into (17), the two transfer functions are obtained, and the TVCF is obtained by multiplication of the two TVCFs.
[0105] An exemplary embodiment of the measure of atrial fibrillation is presented hereinbelow in order to further elucidate these teachings. It should be noted that these teachings are not limited to the exemplary embodiment.
[0106] The detection algorithm was tested on four databases using 128 beat segments: the MIT-BIH AF database, the MIT-BIH normal sinus rhythm (NSR) database (n=18), the MIT-BIH Arrhythmia database (n=48), and a clinical 24-hour Holter AF database (n=15).
[0107] In order to illustrate AF detection, the TVCF are calculated using ARMA (P1=5,Q1=5) with the first order Legendre function for subject 8455 of the MIT-BIH AF database. The first order of Legendre polynomials was used as this choice resulted in the best accuracy for the MIT-BIH AF database (N=23). The optimal ARMA model order was found to be P1=5 and Q1=5 with seg=128, which will be explained in detail in the proceeding section. A 128 beat segment was used which was then shifted by 128 beats. A 64 point FFT was used, which resulted in a frequency resolution of 0.0156 Hz. FIG. 5 shows the resultant TVCFs according to each beat and normalized frequency (assuming a Nyquist frequency of 0.5 Hz). As shown in FIG. 5 , the TVCF values are close to one throughout the entire frequency range for the two adjacent normal sinus rhythm (NSR) data segments. However, the TVCF values significantly decreased when either or both segments partially or fully contained AF.
[0108] As shown in FIG. 5 , it is observed that the TVCF values are highly varying for different frequencies when the patient is in AF. That is, high frequencies tend to have lower coherence values than lower frequencies, in AF (see FIGS. 6 a , 6 b ). To illustrate this phenomenon in more detail, some of the TVCF values are shown selected at various frequencies from FIG. 5 as a function of time in FIG. 6( a ). FIG. 6( b ) shows the corresponding average values of TVCF according to each normalized frequency and each 128-beat segment for both the AF and NSR databases. It is noted that for AF data, TVCF values start close to one at low frequencies but they drop to low values quickly as the frequency increases. However, for NSR data, the TVCFs are nearly constant (slightly decreasing) at near unit values for all frequencies. This can be explained by the fact that the selected ARMA model terms for AF include largely self and its delay of one lag terms (e.g. x(n), x(n-1), y(n) and y(n-1)), as expected, thus, TVCF values will be high only at the low frequencies and become lower as frequencies increase. Also note in the left panel of FIG. 6 , it is observed that the variance of TVCF values is significantly high for AF but nearly constant for NSR.
[0109] Based on the latter observation as described above, AF detection is performed by examining the variance of TVCF through the entire frequency range. For each beat, the variance of TVCF values, termed the frequency variations (FV), is calculated among all frequencies. Using FV-TVCF, the AF detection performance was investigated on the entire MIT-BIH AF database.
[0110] Referring now to FIGS. 7A and 3B , FV-TVCF values and true AF annotation for three representative subjects 4048, 735 and 7162 of the MIT-BIH AF database are shown. In FIG. 7( a ), the data set 4048 contains seven AF episodes with lengths of 206, 66, 37, 34, 388, 40 and 42 beats, and the values of FV-TVCF increase in the beats where AF occurs. In FIG. 7( b ), the data set 735 contains one AF episode with a length of 332 beats whereas for the dataset 7162, AF episodes persist for the entire time segment shown. The FV-TVCF values reflect this by never returning to a value of zero.
[0111] Ectopic Beat Elimination and Shannon Entropy Combination
[0112] A NSR segment including premature or ectopic beats may also result in lower TVCF values. In order to reduce the effect of the premature and ectopic beats, we eliminated outliers and filtered ectopic beats. To summarize, premature or ectopic beats can be recognized by their signature short-long RR sequence between normal RR intervals. For each RR interval in the time series, the ratio RR(i)/RR(i-1) was computed, where RR(i) is the ith beat, and eliminated RR(i) and RR(i+1) when the following three conditions were satisfied: 1) RR(i)/RR(i-1)<perc1, 2) RR(i+1)/RR(i)>perc99 and 3) RR(i+1)/RR(i+2)×perc25, where perc1, perc25 and perc99 are the 1st, 25th and 99th percentiles based on a histogram of the RR interval values, respectively.
[0113] Shannon entropy (SE) as in (19) was also combined with FV-TVCF, to increase the accuracy of AF detection. SE has been shown to be a robust detector of AF and is estimated according to the following calculation:
[0000]
SE
=
-
∑
u
=
1
N
bin
p
(
u
)
log
(
p
(
u
)
)
log
(
1
N
bin
)
(
19
)
[0114] Note that N bin was selected for the best accuracy according to segment lengths while N bin =16 was selected.
[0115] Detector Optimization
[0116] In one embodiment, the condition for AF detection can be given by a simple logical AND condition:
[0117] If (FV≧TH var ) AND (SE≧TH SE ), then classify it as AF.
[0118] Else classify it as non-AF.
[0119] TH var and TH SE are the threshold values of the variance and the Shannon entropy, respectively, and are selected based on the best accuracy; specifically, we used receiver operator characteristic (ROC) analyses. For each combination of TH var and TH SE , the number of True Positives (TP), True Negatives (TN), False Positives (FP) and False Negatives (FN) were found, and used the accuracy (TP+TN)/(TP+TN+FP+FN) on the MIT-BIH AF database. In addition, the sensitivity TP/(TP+FN) and specificity TN/(TN+FP) were calculated. The procedure was repeated by changing the order of ARMA model and the lengths of segments. Note that the ARMA model order was restricted by setting P1=Q1. After finding the values of TH var and TH SE with each different number of model orders and lengths of segments, the same parameters were applied to the databases from MIT-BIH and the clinical AF database.
[0120] In another embodiment of the method for obtaining a measure of atrial fibrillation, the method, using the Root Mean Square of Successive Differences (RMSSD), disclosed in United States Patent Application No. 20110166466, entitled RR INTERVAL MONITORING METHOD AND BLOOD PRESSURE CUFF UTILIZING SAME, published on Jul. 7, 2011, which is incorporated by reference herein is entirety for all purposes, is applied.
[0121] In one or more embodiments, the system of these teachings for physiological parameter monitoring includes a physiological indicator signal sensing component (sensor) and a mobile communication device having an analysis component analyzing the physiological indicator signal to obtain measurements of one or more physiological parameters and a motion artifact detection component detecting effects of motion artifacts in the measurements of the one or more physiological parameters.
[0122] In one instance, the mobile communication device includes one or more processors and one or more computer usable media, where the computer usable media has computer readable code embodied therein that causes the processor to analyze the physiological indicator signal to obtain measurements of one or more physiological parameters and to detect effects of motion artifacts in the measurements of the one or more physiological parameters. In one or more embodiments, the computer readable code causes the processor to implement the methods described hereinabove.
[0123] It should be noted that other embodiments of the mobile communication device, such as the use of ASICs or FPGAs in order to implement the analysis component and/or the motion artifact detection component are within the scope of these teachings.
[0124] FIG. 8 is a block diagram representation of one embodiment of the system of these teachings. Referring to FIG. 8 , in the embodiment shown therein, a mobile communication system 280 includes a processor 250 and one or more memories 260 . A physiological indicator signal sensing component (sensor) 270 supplies a physiological indicators signal to the mobile communication device 280 . The sensor 270 can be a photoplethysmographic (PPG) sensor or an electrocardiogram (EKG) sensor. In the embodiment shown in FIG. 8 , a camera 265 , where the camera as an objective lens 267 , can also supply the physiological indicators signal to the mobile communication device 280 . The one or more memories 260 have computer usable code embodied therein that causes the processor 250 to that causes the processor to analyze the physiological indicator signal to obtain measurements of one or more physiological parameters and to detect effects of motion artifacts in the measurements of the one or more physiological parameters. In one or more instances, the computer readable code causes the processor 250 to perform the implement the methods described hereinabove.
[0125] The one or more memories 260 represent one embodiment of computer usable media having computer readable code embodied therein that causes a processor to implement the methods of these teachings. Embodiments of the method of these teachings are described hereinabove and the computer readable code can cause a processor to implement those embodiments.
[0126] In the embodiment shown in FIG. 8 , the mobile communication device 280 also includes an antenna 265 that enables communications through one or more of a variety of wireless protocols or over wireless networks. It should be noted that, although the sensor 270 is shown as being directly connected to the mobile communication device 280 , embodiments in which the sensor 270 provides the physiological indicators signal to the mobile communication device 280 through a wireless connection are also within the scope of these teachings.
[0127] For the purposes of describing and defining the present teachings, it is noted that the term “substantially” is utilized herein to represent the inherent degree of uncertainty that may be attributed to'any quantitative comparison, value, measurement, or other representation. The term “substantially” is also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
[0128] Elements and components described herein may be further divided into additional components or joined together to form fewer components for performing the same functions.
[0129] Each computer program may be implemented in any programming language, such as assembly language, machine language, a high-level procedural programming language, or an object-oriented programming language. The programming language may be a compiled or interpreted programming language.
[0130] Each computer program may be implemented in a computer program product tangibly embodied in a computer-readable storage device for execution by a computer processor. Method steps of the invention may be performed by a computer processor executing a program tangibly embodied on a computer-readable medium to perform functions of the invention by operating on input and generating output.
[0131] Common forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a CDROM, any other optical medium, any physical medium with patterns of holes, a RAM, a PROM, and EPROM, a FLASH-EPROM, any other memory chip or cartridge, all of which are non-transitory. As stated in the USPTO 2005 Interim Guidelines for Examination of Patent Applications for Patent Subject Matter Eligibility, 1300 Off. Gaz. Pat. Office 142 (Nov. 22, 2005), “On the other hand, from a technological standpoint, a signal encoded with functional descriptive material is similar to a computer-readable memory encoded with functional descriptive material, in that they both create a functional interrelationship with a computer. In other words, a computer is able to execute the encoded functions, regardless of whether the format is a disk or a signal.”
[0132] Although the invention has been described with respect to various embodiments, it should be realized these teachings are also capable of a wide variety of further and other embodiments within the spirit and scope of the appended claims. | Systems and methods that enable physiological monitoring with a mobile communication device and that allow detection of motion artifacts so that the results reported are of acceptable quality are disclosed. | 0 |
BACKGROUND OF THE INVENTION
It is known to provide spring motors having longitudinally symmetrical tapered flat tapes that produce variable reactive forces. Early examples are disclosed in a 1952 U.S. Pat. No. 2,609,193 to Foster, and in later U.S. Pat. Nos. 3,194,343 and 3,194,344 to Sindlinger. Foster discloses a so-called “A”-type spring motor, and Sindlinger discloses a so-called “B”-type spring motor.
In a B-type motor, a length of pre-stressed tape, or ribbon, is wrapped around first and second spools rotatable about spaced parallel axes. Each spool has a circular hub and a pair of circular flanges extending outwardly from the hub in spaced parallel relation. The tape is wrapped about the spool hubs such as in the manner described in referenced Sindlinger patents to form a spring motor assembly. In such an assembly, when one of the spools, such as the driver spool, is rotated about its axis, the tape element reacts as it separates from the driven spool, and causes either more, or less, torque to be required to rotate the driver spool. Either spool may be connected to a variety of prime mover mechanisms, such as a lanyard wrapped about a pulley, so that linear motion of the lanyard is converted to rotational motion. A simple practical application of this mechanism can be found in counterweighting window sashes and window treatments wherein the present invention also finds utility.
In published, but abandoned, U.S. Patent Application published as No. 2009/0108511 A1, several variations of a tapered spring tape are disclosed. In one such variation, illustrated in FIGS. 10 and 11 , the tape has a single longitudinal straight edge and a single tapered edge extending between opposite ends. While such a tape may provide some theoretical advantages, the Published Application does not disclose any information about how to manufacture such a tape efficiently.
While the disclosed patented and published flat tapered tape spring motor mechanisms may function satisfactorily for their intended purposes, none is capable of being manufactured efficiently. Thus, there is a need for a flat tapered tape spring that is capable of being manufactured efficiently using commercially available equipment employed in a novel process. Moreover, there is a need for a tapered flat tape B-motor that can be used effectively in product display tethering applications, such as currently provided by the PULLBOX® product manufactured by applicant's assignee Vulcan Spring and Manufacturing, Inc. of Telford, Pa.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view the major components of a so-called B-type spring motor;
FIG. 2 is a plan view of the motor illustrated in FIG. 1 ;
FIG. 3 is an elevational view of the motor illustrated in FIG. 2 ;
FIG. 4 is an end elevational view taken on line 4 - 4 of FIG. 3 ;
FIG. 5 is a sectional view taken on line 5 - 5 of FIG. 2 ;
FIG. 6 is a plan view of the spring tape form shown prior to winding into a form suitable for assembly into the motor of FIG. 1 ;
FIG. 7 is an elevational view similar to FIG. 3 but of a modified embodiment;
FIG. 8 is an end view similar to FIG. 4 but of the modified embodiment;
FIG. 9 is a sectional view similar to FIG. 5 , but of the modified embodiment;
FIG. 10 is a plan view similar to FIG. 6 but of a tape used in the modified embodiment;
FIG. 11 is a plan view of a length of tape prior to being cut to length to form the tape of FIG. 10 ; and
FIG. 12 is a schematic view illustrating the process for making spring tapes, such as the one illustrated in FIG. 10 .
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings, FIG. 1 illustrates in perspective the major elements of a B-type flat spring motor 10 . These elements include a drive spool 12 , a driven spool 14 , and a flat tape spring element 16 wrapped around the spools 12 , 14 in the manner illustrated. As best seen in FIG. 5 , each spool, such as spool 14 , is characterized by a central cylindrical hub 18 and a pair of circular flanges 20 , 22 extending radially outward in spaced parallel relation from the hub 18 . The gap between the hub and the inner surfaces of the flanges provides space for the tape spring 16 to occupy as it is displaced from one spool to the other during operation of the motor. By way of example, when a torque is applied to the driver spool 12 in the counter-clockwise direction of the arrow shown in FIG. 1 , the tape 16 advances rightward under the spool hub from a location over the hub on the driven spool 14 . The action and reaction of the spring tape is well known and need not be further discussed in detail at this juncture.
In one aspect of the invention, as best seen in FIG. 6 , the flat spring element 16 is elongate and has end portions 16 a and 16 b located at opposite ends of a tapered intermediate portion 16 c . The spring element 16 has an elongate guide edge 17 a that extends the full length of the spring element, and has a free edge 17 b that tapers relative to the guide edge 17 a between the opposite end portions 16 a and 16 b . One of the end portions 16 b has a short transverse edge portion that cooperates with the guide edge 17 a to define the minimum width of the tape at one end portion thereof. The opposite end portion 16 a extends transversely across the full width of the tape. This shape is that of a right trapezoid in plan. Preferably, as best seen in FIG. 5 , the hub 19 on the companion spool 12 is frustoconical. As seen in FIGS. 3 , 4 and 5 , the guide edge 17 a engages the inside surfaces of the spool flanges to keep the tape properly centered as the tape moves, and the frusto-conical surface of the spool hub 19 assists in this function.
If the motor is used in applications where low operating noise is desired, a tapered spring tape 24 of the configuration illustrated in FIG. 10 is desirable. This tape configuration possesses modified end portions that tend to cause the motor to run quietly. In this embodiment, the end portions 25 and 26 of tape 24 have full width sections at both opposite ends of the tapered section 27 . As in the FIG. 6 embodiment, the tapered section 27 has a guide edge 27 a and a free edge 27 b . The guide edge 27 a runs the full length L of the tape, and the free edge 27 b extends for less than the full length by the dimensions L1 and L2. The lengthwise extent, L1 and L2 of each end portion corresponds to at least X. π. D of the spool hub about which each end portion is to be wrapped. The letter “X” equals the number of complete wraps needed to provide adequate hub/flange/tape engagement for centering the tape ends between the spool flanges during initial periods of extension and retraction of the spring tape. The letter “D” equals the diameter of the spool hub. As seen in FIGS. 3 and 4 , the guide edge 17 a continually engages one flange on both driver and driven spools to provide proper centering of the tape as it advances and retracts. The free edge tapers at a constant rate and provides the force that varies with length. In this embodiment a frusto conical spool hub 19 ( FIG. 5 ) is not required.
Regardless, of which spring tape embodiment is desired, both can be produced by essentially the same process using the same equipment, as illustrated schematically in FIG. 12 . In the process, an indeterminate length 30 of flaccid metal tape, preferably of high tensile strength spring steel, is provided on a supply roll 32 . The tape 30 is unrolled and advanced lengthwise, such as horizontally, between support and drive rollers 31 and 33 . While being advanced, the tape 30 is cut by a laser beam B directed downwardly from a head 38 which is moveable transversely relative to the longitudinal path of movement of the tape 30 . The laser beam B makes a linear cut 40 in the tape to provide a free edge 40 that extends at an angle across the longitudinal medial axis M of the tape 30 , but does not extend all the way across the tape 30 . At predetermined intervals, the laser beam B makes a transverse cut 44 connected to the linear cut 40 . The transverse cut 44 forms a continuous free edge in a saw tooth configuration as illustrated in Section A-A downstream of the laser head 38 . To make this cut, either the longitudinal motion of the tape is briefly halted, or the laser head 38 is moved above the tape at a velocity that is synchronized with the velocity of the tape. It should be apparent that the rotational speeds of the drive rolls 31 and 33 are synchronized by suitable controls with the motion of the laser head 38 .
The continuous free edge cuts 40 and 44 form the tape into undulating complementary shapes on opposite sides of the medial axis M downstream of the laser beam B. As the cut tape advances, it engages a stationary separator nose 48 that splits the tape into two identical complementary shaped strips, Section B-B and Section C-C. One of the strips, Section C-C, advances downwardly onto a storage roll 46 for subsequent use. The other strip Section B-B advances horizontally into a spring coiler 50 which pre-stresses the strip by known techniques, and then cuts the stressed strip to a desired length. The operation of the spring coiler 50 is coordinated with the linear speed of the tape 30 . Also, a suitable slack provider may be emplaced between the separator nose 48 and the coiler 50 , as well known in the art. The thus-coiled tapered spring tape 30 is discharged into a collection bin 52 for further processing, such as customary heat treating, before being assembled into a spring motor. Preferably, the end portions of the tape are formed with keyholes for engaging fastener lugs on the spool hubs, as known in the art.
In the above-described process, the spring tape 30 is cut completely widthwise in the coiler 50 by means of a die 51 . When the cut is aligned with the transverse cuts, shown in Section B-B, the resulting strip has a wide end, and a narrow end, and yields a tape form as illustrated in FIG. 6 . Such a tape spring is useful in applications where a very quiet running motor is not required.
It is important to note that Section B-B is the complement to Section C-C. Thus, it can be further processed in the same manner as Section B-B, as by being removed from its storage reel and fed into the same, or a parallel, coiling machine. The point is that the complementary cutting ensures that none of the material of the flaccid starting tape material 30 is wasted.
In order to produce the spring tape embodiment of FIG. 10 , the laser cutting beam B is held stationary adjacent one, or the other, edges of the tape for brief periods of time as the tape advances. As a result, the laser beam B cuts the tape lengthwise for predetermined lengths L1 and L2 before resuming its transverse crosswise motion, as described above. This causes the opposite ends of the tape to have full width sections at both opposite ends, as shown in FIGS. 10 and 11 for purposes previously discussed.
In the illustrated embodiment, the undulating free edge is linear, having tapered sections and transverse sections. There may, however, be applications where these undulating free edges may have a long-wave sinusoidal shape. Whether the free edge is linear, or long-wave sinusoidal, or a is composed of combination of curved and straight sections, the important aspect of efficient production is to provide complementary shapes on opposite sides of the medial axis of the tape so that minimal material is wasted in making the finished tape element. | A spring tape suitable for use in spring motor applications where reactive torque varies with rotational deflection. An elongate elastic element is advanced lengthwise and is laser cut into longitudinally complementary shapes which are separated and subsequently pre-stressed into rolls which are cut to length for assembly into a spring motor. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to movie equipment dollies for transporting movie or television filming apparatus, such as cameras, during filming.
Movie dollies are moveable hoist apparatus that are used in the film industry to support and move cameras and other equipment during film sequences. Known designs of dollies have lift arms, often hydraulically controlled, for adjusting camera elevation, a camera head assembly attached to the end of the lift arm for adjusting the pitch and roll orientation of a camera affixed to the arm and preferably four steerable wheels for translation of the dolly, when a film crew wants to move the camera during film sequences. Three types of dolly steering modes have been traditionally desired in the film industry and they are shown in FIGS. 1-3:
FIG. 1 shows the so-called crab steering mode, wherein the rolling or steering axes of the four steerable wheels are oriented in parallel. In the crab steering mode, the dolly moves generally laterally, as shown by the arrow in FIG. 1, the degree of lateral movement being controlled by the steering handle.
FIG. 2 shows the so-called circular steering mode, wherein the rolling or steering axes of the four steerable wheels are oriented to intersect at a common point, which establishes a circular turning radius. In the circular steering mode, the dolly translates in a circle, as indicated by the arrow in FIG. 2, with the diameter of the steering circle being controlled by the steering handle.
FIG. 3 shows the neutral steering mode, wherein the rolling axes of all four wheels are independently orientable and they are not steered by the steering handle. Rather, the wheels ride on a set of pre-laid tracks, similar to railroad tracks. In the neutral steering mode, the dolly wheels must be disengaged from the steering mechanism.
Previous dolly designs have accomplished all three desired steering modes by use of a transmission coupled to the steering mechanism and the steerable wheels, having selectable crab or circular steering modes, and means to disengage the steerable wheels from the steering system for the neutral mode. Known designs of movie dollies are described in U.S. Pat. Nos. 2,950,121; 3,022,901; 3,168,284; 4,109,678; 4,257,619; and 4,360,187.
Unfortunately, known movie dollies suffer from shortcomings that hamper efficient use by film crew personnel. Known camera levelling heads utilize three or more adjustment screw to orient pitch and roll of the movie camera relative to the lift arm, to level the camera. With three or more adjusting screws, a cameraman can not simultaneously adjust camera pitch and roll, which delays adjustment--a critical flaw during fast-moving action film sequences. Known levelling head designs are bulky, which increases dolly weight and height. Levelling head height restricts how low a camera can be oriented to the ground. Very low film shots cannot be attained with known levelling heads, unless they are attached to the lifting arm with an offset bracket.
Known movie dolly transmissions are bulky, heavy and have complicated designs encompassing inordinate numbers of moving parts that complicate transmission maintenance. It is desirable to manufacture lighter weight movie dollies than previous designs, to reduce the labor required to lift dollies, for example, from transport vehicles to outdoor filming locations. One effective way to reduce dolly weight is to decrease transmission weight and bulk. When shifting known dollies into or out of neutral steering mode, the film crew must perform one of two procedures. In one known design, a separate clutch mechanism, located on each wheel, must be disengaged in order to select the neutral steering mode and to get out of the neutral mode, each wheel must be separately indexed for reconnection to the steering system by manually aligning index marks on each wheel assembly and re-engaging the clutch mechanism. In a second known design, a pin is removed from each wheel assembly to select neutral steering, but to get out of the neutral mode, each wheel must be separately indexed for pin alignment before reinserting the pins. Both known designs require time-consuming manual realignment of the dolly wheels, in order to disengage the neutral steering mode.
Another shortcoming in known movie dolly construction is poor operator ergonomics. Steering, hydraulic lift actuation and transmission steering mode shifting on known dollies are performed on at least two separate control handles or are not accessible without removing at least one hand from the steering handle. The dolly operator normally prefers to keep both of his or her hands on the steering handle and if a rapid vertical camera height adjustment is needed while steering, the operator cannot maintain both hands on the steering handle. Rapid action sequences in many of today's popular films require maximum dolly operator efficiency.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the shortcomings inherent in known movie dolly designs. Specifically, it is an object of the present invention to develop a movie equipment dolly levelling head having rapid, simultaneous roll and pitch adjustment capabilities, lightweight construction, and low vertical height, to allow the lowest possible angle film shots.
It is another object of the present invention to develop a compact, lightweight transmission that has multiple selectable steering modes with the fewest number of moving parts for ease of maintenance and service.
It is a further object of the present invention to develop a movie dolly with steerable wheels that can shift to or out of the neutral steering mode without the necessity of manually aligning components.
It is additional object of the present invention to develop an ergonomically efficient control handle that combines dolly steering, transmission steering mode selection and lifting arm height adjustment in a single control handle, so that the operator's hands can remain in one position. As part of this object, it is desirable to have each control function actuated by a different kind of gross hand movement, so that the operator is always cognizant of what type of control function he is performing.
Further, it is an object of the present invention to develop a movie dolly that can accomplish any one or more of the foregoing objects.
The foregoing objects are attained by the movie equipment dolly of the present invention, which is described and claimed in greater detail including reference to the drawings which form a part of this specification.
The movie equipment dolly of the present invention features a chassis; a lifting arm connected to the chassis; and a levelling head connected to the lifting arm, having a platform for mounting of a camera device thereon, and means for simultaneously orienting pitch and roll axes of the levelling head, connected to the platform and the lifting arm.
In certain embodiments, the movie equipment dolly of the present invention also features a chassis; at least two steerable wheels connected to the chassis for moving the dolly; means for the steering the steerable wheels; and a transmission for orienting the wheels into selectable steering modes connected to the chassis, having a selectively rotatable transmission shaft connected to the means for steering, a first transmission pulley connected to the shaft, and connected to a first one of the steerable wheels, a second transmission pulley connected to the shaft, and to a second one of the steerable wheels, and means for selectively varying the relative rotation of the first and second pulleys, so that the first and second wheels are separately oriented along selected relative steering axes by the means for steering.
The movie equipment dolly of the present invention also features a chassis; a plurality of steerable wheels connected to the chassis for moving the dolly; means for steering the wheels; and a plurality of slip idlers connected to the wheels and the chassis, having means for selectively connecting and disconnecting the slip idlers from the means for steering and means for simultaneously connecting and disconnecting in unison at least two of the slip idlers.
Lastly, the present invention also features a movie equipment dolly having a chassis; a lifting arm connected to the chassis; means for lifting the lifting arm upon actuation thereof and connected to the lifting arm; at least one steerable wheel connected to the chassis for moving the dolly; a transmission connected to the wheel for orienting the wheel into selectable steering modes upon actuation thereof; and a control handle having a rotatable steering shaft connected to the wheel for steering the wheel, at least one moveable grip portion connected to the steering shaft and the transmission for rotating the shaft and for actuating the transmission and a lever means connected to the steering shaft and the lifting means, for actuating the lifting means.
Any one or more of the features of the movie equipment dolly of the present invention may be combined.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows schematically a movie dolly in the crab steering mode.
FIG. 2 shows schematically a movie dolly in the circular steering mode.
FIG. 3 shows schematically a movie dolly in the neutral steering mode, mounted on a set of tracks.
FIG. 4 is a front perspective view of the movie equipment dolly of the present invention, with the lifting arm in a selected intermediate vertical position.
FIG. 5 is a front perspective view similar to FIG. 4, but showing the lifting arm in its lowermost position.
FIG. 6 is a front, partial cutaway, perspective view of the dolly chassis of the present invention, showing the transmission and steering systems.
FIG. 7 is an elevational, exploded view of the dolly transmission of the present invention.
FIG. 8 is an elevational, cross-sectional view of the dolly transmission shifted into the crab steering mode.
FIG. 9 is a cross-sectional view similar to FIG. 8, but with the transmission shifted into the circular steering mode.
FIG. 10 is an axial, cross-sectional, elevational view of the slip idler of the present invention, when the neutral steering mode is not selected.
FIG. 11 is a front axial, cross-sectional, elevational view of the slip idler of the present invention, when it is set in the neutral steering mode.
FIG. 12 is a front, partial cutaway, perspective view of the slip idler gear actuating lever assembly.
FIG. 13 is a front, partially exploded, perspective view of the lifting arm of the present invention.
FIG. 14 is a schematic diagram of the lifting arm hydraulic system, which provides means for lifting the lifting arm.
FIG. 15 is a elevational view of the levelling head of the present invention.
FIG. 16 is an exploded view of the levelling head of the present invention.
FIG. 17 is a front perspective, elevational, partial cut-away view of the control handle of the present invention.
FIG. 18 is a fragmentary, rear-elevational, perspective view of a portion of the control handle of FIG. 17, showing the middle tube coupled to the grip portion eccentric crank.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A better understanding of the present invention may be achieved by reference to the drawing figures which are part of this specification.
FIGS. 4 and 5 show generally a movie equipment dolly 1 constructed in accordance with the teachings of the present invention, having a chassis 2, and a lifting arm 3 coupled to the chassis and hydraulically actuated by hydraulic cylinders 4. A levelling head 5 is coupled to the lifting arm 3 and has a platform 6 for mounting of a movie equipment device thereon, such as a motion picture camera.
The movie dolly 1 has four steerable wheels 7, three of which are visible, and a control handle 8 for steering the wheels by rotating the handle 8, as shown. Alternatively, the equipment dolly may have three wheels. The control handle 8 can be used to select the crab or circular steering modes by twisting grip portion 9. Lifting arm 3 hydraulic system actuation is performed by rocking control lever 10 up to raise the arm and down to lower the arm. The neutral steering mode is selected by upwardly reciprocating the slip idler gear actuating levers Il.
FIG. 6 shows the means for coupling the steerable wheels 7 to the steering mechanism. To that end, a steering sprocket 12 is connected to a transmission 13 by drive chain 14. The control handle 8, shown in FIG. 4, is coupled to the steering sprocket 12 and is indicated by the shaft stub projecting upwardly from the steering sprocket.
The wheels 7 preferably are steered by chain drive means that couple them to the transmission 13 and in turn to the steering sprocket 12. More specifically, each wheel has a drive chain, connected to the transmission 13 and a slip idler 15; the slip idler and a corresponding wheel sprocket for the driven wheel are in turn connected by a driven chain. By placing a slip idler 15 between the drive and driven chains, a user can selectively disengage the slip idler so that the wheels 7 are no longer controlled by the control handle 8 when the neutral steering mode is desired. Normal idler sprockets 16 (not slip idlers) and chain tensioners 17 can be installed as needed to route chains in the chassis 1 and eliminate chain slack. The chain courses run as follows: The right front drive chain 18 for the right front wheel is coupled to the transmission 13 and slip idler 15 and right front driven chain 19 is coupled to the slip idler and to right front sprocket 20. The left front wheel is coupled to the transmission 13 by left front drive chain 21 which is routed to slip idler 15 and the left front driven chain 22 is in turn connected to the slip idler and the left front wheel sprocket 23.
The rear wheels are driven off a common transmission pulley, to be described in detail when referring to FIG. 7 herein, by a common rear drive chain 24 to a pair of slip idlers 15 (one for each rear wheel), with the right rear side slip idler connected to right rear driven chain 25 and in turn the right rear wheel sprocket 26, for the right rear wheel, and the left rear slip idler connected to left rear driven chain 27, and left rear wheel sprocket 28, for the left rear wheel.
While the preferred embodiment of the present invention utilizes chain drive means to couple the dolly wheels, transmission and steering, other forms of drive means can be used, such as cogged belts and pulleys, in which case, pulleys are substituted for the chain sprockets shown and described herein.
FIG. 7 shows an exploded view of the transmission of the present invention, which utilizes a small number of parts--only four pulleys, a pair of levers and four pins--and provides a compact, lightweight design suitable for movie dollies. In the preferred embodiment, the four pulleys are toothed sprockets for receipt of the three wheel drive chains 18, 21 and 24 and the steering drive chain 14.
Transmission 13 has a transmission shaft 29, over which is fitted first sprocket 30 having a center bore 31 that allows rotation of the sprocket thereon. The second sprocket 32 is rigidly attached to shaft 29 through center bore 33 by known means such as welding, splines or keys. The third sprocket 34 is rotatably mounted on shaft 29 at center bore 35. The third sprocket 34 has a cam groove 36 therein, having a varying radius relative to the sprocket's rotational center.
In the preferred embodiment, the transmission 13 has a fourth pulley sprocket 36A, which is coupled to steering chain 14, the steering sprocket 12 and the control handle 8. Sprocket 36A is rigidly coupled to the transmission shaft 29. First sprocket 30 is coupled to the left front wheel drive chain 21, to rotate the left front wheel. The second sprocket 32 is coupled to the right front drive chain 18, to steer the right front wheel. Third sprocket 34 is coupled to the rear wheels drive chain 24, to steer both rear wheels.
The transmission 13 also has a first lever 37 having a shaft 38, a lever arm 39 and a lever arm pin 40 that rotatably mates into a bore on the bottom of the first sprocket 30, which is not shown, thereby coupling the lever to the sprocket. First lever shaft 38 passes through lever bore 41 in the second sprocket 32 and is rotatable in the bore. Thus, rotation of the second sprocket 32 circularly translates the first lever shaft 38, which in turn rotates the first sprocket 30.
Transmission second lever 42 has a bore 43 that rigidly receives first lever shaft 38 (e.g. by welding, splines or a key and keyway) so that levers 37 and 42 maintain constant relative positions. The second lever 42 also has a second lever arm 44 with a second lever pin 45 that slidably rides in the cam groove 36 in the third sprocket 34. The first and third sprockets 30 and 34 freely rotate relative to the second sprocket 32. By virtue of the offset, rigidly coupled transmission levers 37 and 42, rotation of shaft 29, by turning the control handle 8, rotates the second sprocket 32 at one angular velocity, but the lever arrangement causes the first sprocket 30 to rotate at a different angular velocity than the second sprocket. The difference in angular velocity rates is controlled by the profile of cam groove 36 on the third sprocket 34. Thus, as one skilled in the art can appreciate, varying the profile of cam groove 36 changes the relative orientation of the left front wheel (coupled to the first sprocket), and the right front wheel (coupled to the second sprocket) so that both front wheels can be properly oriented in the circular steering mode.
Next, the shift actuation system is explained by reference to FIGS. 7-9. The first, second and third sprockets 30, 32, 34 each have pin bores 46, 47, 48, respectively, for reciprocable passage of transmission pins 49-52 therethrough. The transmission pins 49-52 are reciprocated by shift actuator 53 having a shift actuator shaft 54. Shift actuator 53 has a down position, shown in FIG. 8, when the dolly is in the crab steering mode and an up position, shown in FIG. 9, when the dolly is in the circular steering mode. A transmission stop plate 55 is slidable over shaft 54 and, in conjunction with the actuator 53, restrains the pins 49-52 therebetween.
The length of each transmission pin 49-52 is specifically chosen so that when the shift actuator is in the down, or crab steering mode, pin 49 is between sprockets 30 and 32, pin 50 is between sprockets 32 and 34 and pins 51 and 52 are in chassis bore 56 of chassis boss 57. Yet, the length of each pin 49-51 is also chosen so that when the shift actuator is in the up, or circular steering mode, pin 49 is only captured in sprocket 30, pin 50 is only captured in sprocket 32, pin 51 is captured between sprocket 34 and chassis boss 57 (thereby blocking rotation of sprocket 34) and pin 52 is captured within the chassis boss. One skilled in the art can appreciate that pins 51 and 52 can be combined into one single pin.
Thus, when the shift actuator 53 is in the down position or crab steering mode, the first, second and third sprockets 30, 32 and 34 are locked together for common rotation and the four wheels have parallel steering axes, as shown in FIG. 1. Rotating control handle 8 rotates steering sprocket 12 and drive chain 14, which rotates the fourth sprocket 36A and the first, second and third sprockets 30, 32 and 34 in unison, so that all four wheels are steered in parallel.
When the shift actuator is in the up, or circular steering mode, rotation of the .third sprocket 34 is blocked, along with rotation of the dolly rear wheels as shown in FIG. 2, but the first and second sprockets 30 and 32 are rotatable relative to the blocked third sprocket 34, subject to the mutual relative rotational constraints posed by the second lever 42 riding in the cam groove 36, which orients the steering axes of both the dolly front wheels to a common point of intersection with the rear wheels steering axes. Rotation of the steering control handle 8 steers only the left and right front wheels.
The slip idler 15 of the present invention, used to select the neutral steering mode, is shown schematically in FIGS. 10 and 11. It comprises a pair of opposed first and second idler sprockets 58 and 59, respectively, reciprocable from a first neutral position proximate each other (FIG. 10) when the slip idler is not in the neutral steering mode to a second position distal each other (FIG. 11), when the slip idler is in the neutral steering mode.
The first sprocket 58 has at least one dog 60 projecting from it towards the second idler sprocket 59 and the dog is engageable in a recess 61 defined by the second idler sprocket, when the sprockets are proximate each other. The positions of the dog 60 and recess 61 can be transposed from one sprocket to the other. Desirably, the sprockets 58 and 59 have a plurality of dogs and recesses configured so that each dog is engageable in only one recess, so that the idler sprockets are orientable only in a single indexed position relative to each other. The sprockets 58 and 59 receive a drive chain and a driven chain so that rotational torque is transmitted from the drive chain to the driven chain when the slip idler is not in the neutral steering mode.
The slip idler 15 has an idler shaft 62 that has an idler shaft flange 63. The slip idler 15 has first bearing means, a roller bearing 64 that connects the shaft 62 to the first sprocket 58 and a second bearing means, a roller bearing 65 that connects the second sprocket 59 to a slip idler base 66, which base is connected to the chassis 2. The shaft 62 reciprocates relative to the base 66.
As shown in FIG. 12, the slip idler shaft flanges 63 are captured to within idler forks 63A that are connected to the slip idler actuating lever 11 and the lever is pivotably attached to the chassis 2 by lever flanges 63B. In operation, upwardly reciprocating lever 11 shifts the wheels 7 into the neutral steering mode, by separating the opposed sprockets 58 and 59 and rotational torque is not transmitted from wheel drive chains to the driven chains. Thus, rotation of the steering control handle 8 only rotates the drive chains 18, 21 and 24, but not the corresponding driven chains 19, 22, 25 and 27.
Downwardly reciprocating the slip idler lever 11 urges the sprockets 58 and 59 toward each other, to enable the dogs 60 to mate in the recesses 61. After downwardly reciprocating the slip idler lever 11, rotation of the control handle 8 rotates idler sprocket 58 relative to sprocket 59 until the dogs 60 and recesses 61 index relative to each other and mate to allow rotational torque transmittal between the sprockets. As shown in the preferred embodiment, slip idler actuating lever 11 is a means for simultaneously connecting and disconnecting in unison two slip idlers 15.
While FIG. 12 only shows a lever for actuating the right side wheels slip idlers, an identical lever assembly is utilized for the left side wheels. If desired, both the right and left wheels levers can be combined into a common, centrally located handle. As a cost-saving measure, the lever assemblies 11 can be deleted, but selecting the neutral steering mode would require turning over the dolly 1 in order to reciprocate the slip idler shafts 62.
FIG. 13 shows an exploded view of the lifting arm 3 of FIGS. 4 and 5, which is a scissor-type arms the operation of which will be explained after setting forth the structural relationship of the arm components. Arm 3 has three main component groups: a right arm housing 67, a center arm housing 68 and a left arm housing 69. The center arm housing 68 contains a crank 70 that is connected to levelling head 5 and rotates about shaft 71 running through the housing on journals. Another arm of crank 70 is rotatably connected to the center levelling arm rod 72 which in turn rotatably connects to an arm of crank 73. Crank 73 is rigidly connected to crank 74 by shaft 75, which in turn rides in journaled shaft 76, but shaft 76 is rigidly mounted in center arm housing 68.
Shaft 75 may be extended on either side to accommodate a bracket for a cameraman's seat, which is not shown. Crank 74 rotatably connects to levelling rod 77, which is in turn rotatably connected to crank 78. Crank 78 is rigidly connected to shaft 79 that rigidly connects to the chassis, 2 but which is rotatably connected to housing 69. Shaft 80 is also rigidly attached to chassis, 2 but also rotatably connected to housing 67. Rigidly attached to shaft 80 are sector-shaped primary sprocket 81 and secondary sprocket 82, which may be either sector- or circular-shaped. Sector-shaped primary sprocket 83 and the secondary sprocket 84 are rigidly connected to shaft 76, with the secondary sprocket 84 having either a circular or sector shape.
The primary sprockets 81 and 83 are connected by primary chain 85, which rotates shaft 75 and the secondary sprockets 82 and 84 are connected by secondary chain 86, which takes slack out of the primary chain and prevents manual lifting of the arms.
Primary sprocket 81 and secondary sprocket 82 have twice the diameter of corresponding primary sprocket 83 and secondary sprocket 84, to insure that shaft 76 counter-rotates at twice the angular velocity of the left and right arm housings 67 and 69.
As those skilled in the art can appreciate, the object of a scissor-type lifting arm, such as that described herein, is to allow vertical translation of the levelling head 5 without changing orientation of the platform 6 relative to the ground upon which the dolly is situated. In the lifting arm 3, vertical translation is effected by the right, center and left arm housings, 67, 68 and 69, in conjunction with the sprockets and chains contained in the right housing and the hydraulic cylinders 4. The cranks and levelling rods contained in the center and left arm housing 68 and 69 maintain a constant orientation of the levelling head platform 6 relative to the ground.
To lift the arm 3, the hydraulic cylinders 4 are pressurized, thereby rotating the right and left arm housings 67 and 69 counterclockwise and the primary sprockets 81 and 83 and primary chain 85 counter-rotate the center arm housing 68 in a clockwise direction at twice the angular velocity of the left and right arm housings.
In contrast to the arm housings 67, 68 and 69, the shafts 71, 75 and 79, onto which the corresponding cranks 70, 73, 74 and 78 are rigidly attached, cannot change their angular orientation relative to the ground during arm housing rotation, because those shafts are rotatable relative to the housings. Shaft 79 is rigidly attached to the chassis 2 and by means of crank 78, levelling rod 77 and crank 74, and prevents angular rotation of shaft 75. Since shaft 75 cannot rotate, crank 73 and levelling rod 72 prevent angular rotation of crank 70, onto which the levelling head platform 6 is mounted. Accordingly, the levelling head platform 6 maintains the same angular orientation of shaft 79, which is rigidly attached to the chassis 2.
The means for lifting the lifting arm 3 is the hydraulic system shown in FIG. 14. The system works on the principle of a high pressure hydraulic accumulator 87 supplying the hydraulic cylinders 4 with pressurized fluid, that is in turn vented to an ambient pressure common reservoir 88. All components of the hydraulic system are of known construction. It is desirable, but not required, for both the accumulator 87 and the reservoir 88 to be mounted in the chassis for a more compact design.
The accumulator 87 connects to a bleed valve 89 for selective pressure discharging thereof and to a variable pressure relief valve 90 to prevent explosive overpressurization of the accumulator. The accumulator 87 is also connected in parallel to a hydraulic system actuator, which is preferably a manually-operated, spring-centered directional control valve 91 that is connected to a needle valve 92, for setting the desired arm raising and lowering speed, and the needle valve is in turn connected to the hydraulic cylinders 4. To relieve pressure in the hydraulic cylinders 4, they are connected back to the control valve 91 and in turn to the reservoir 88. Rocking an actuator lever on the control valve 91 in one direction routes more pressurized fluid to the cylinders 4 and rocking the valve lever in another direction allows pressurized fluid to escape the cylinders to the reservoir 88.
To charge the accumulator 87, it is connected by ball valve 93 to motorized pump 94, which pumps hydraulic fluid from the reservoir 88 to the accumulator 87. For safety, an electrical cutoff switch 95 is connected in parallel to the accumulator 87 and shuts off the pump motor 96 when a preset system pressure is attained. Gauge 97 allows reading of the system pressure. A manual pump 98 is selectively connectable to the hydraulic system by ball valve 99, in case of electrical motor failure or in locations without electricity. A common ball valve may be used for either the motorized pump 94 or the manual pump 98 and the operator would selectively connect the desired pump to the valve.
To lift the arm 3, the control valve 91 lever is rocked in the pressurization direction to add pressurized fluid to the hydraulic cylinders 4, which retracts the cylinder pistons into the cylinders and rotates the right and left arm housings 67 and 69 in a counterclockwise direction, shown in the right perspective view of FIG. 13. Rocking the control valve 91 lever in the depressurization direction allows pressurized fluid to escape the cylinders 4 and allows the arm housings 67 and 69 to pull the cylinders 4 pistons out of the cylinders, which rotates the arm housings in a clockwise direction, shown in the right perspective view.
FIGS. 15 and 16 show the dolly levelling head 5 of the present invention. The levelling head 5 has a platform 6 with pivot means for coupling the platform to the lifting arm crank 70, such as the universal joint 100 shown. Universal joint 100 is attached to crank 70 by pin 101 and the joint is captured by saddle blocks 102, which bolt to the platform 6. An alternative pivoting means is a ball and socket joint, not shown, or any other suitable device which allows at least two degrees of rotational movement freedom. A pair of reciprocable adjuster means is each coupled to the crank 70 and is shown in FIG. 15 as a female threaded screw adjuster wheel 103 which mates with male threaded member bolt 104.
As a desirable, but not required feature, the adjusting means has a pivoting means to insure proper alignment with the platform 6. As shown in FIG. 15, the adjusting means pivoting means is a universal joint and in FIG. 16, the pivoting means is a ball and socket joint 106.
Rotating both adjuster wheels 103 at the same rate changes the levelling head 5 pitch orientation and rotating only one or the other adjuster wheel changes the levelling head roll orientation. Changing the relative rotation rate of both adjuster wheels 103 simultaneously changes both the pitch and roll orientation of the levelling head 5.
As shown in FIG. 5, the compact design of the levelling head 5, in conjunction with the lifting arm 3, allows the head to be virtually flush with the top of chassis 2 and allows the lowest possible movie shooting angles, which advantageously increases the dolly's operational flexibility for enhanced filming creativity. FIG. 17 shows in detail the control handle 8 of the present invention. Handle 8 has a rotatable steering shaft 107 which is shown as tubular, and which is connected to the steering sprocket 12. As previously described, sprocket 12 translates drive chain 14, which is connected to transmission sprocket 36A. Rotation of the transmission sprocket 36A rotates the remainder of the chain-driven wheel steering means and turns the steerable wheels 7, when the slip idlers 15 are not in the neutral, disconnected mode. Bearing 108 is connected to the chassis 2 and supports the steering shaft 107.
The control handle 8 has a body onto which is attached at least one, but preferably two grip portions 9, at least one of which is shown as the left-most one (110) in FIG. 16. Attached to the grip portion 110 is an eccentric crank 111 having an eccentrically offset pin member 112, that is coupled to a middle tube 113, nested within the shaft 107, by riding in a groove 114 on the upper end of the middle tube, as shown in FIG. 18. The bottom end of the middle tube 113 is connected to the shift actuator 53. Twisting the grip portion 110 rotates the grip portion crank 111 and in turn reciprocates the middle tube 113 and the shift actuator 53. As shown in conjunction with FIGS. 8 and 9, twisting the grip portion 110 in either direction actuates the transmission into either the crab or circular steering mode.
The control handle 8 also has lever means 115 coupled to the control handle body 109, a bell crank 116 having a rotational axis coupled to the body and first and second arms 117, 118, with the first arm coupled to the lever 115 and the second arm coupled to a reciprocable inner member 119 nested within the middle tube 113. The inner member 119 is coupled to the hydraulic actuator lever 91A. Rocking the lever means 115 reciprocates the inner member 119 and in turn rocks the hydraulic actuator lever 91A to route more pressurized fluid to the hydraulic cylinders 4 or to let pressurized fluid escape from the cylinders, depending on which position the operator rocks the lever means 115.
Although the invention has been described with reference to the preferred embodiment, it should be apparent to those skilled in the art that various modifications and improvements may be made in and to the dolly, without departing from the spirit and scope of the invention. | The present invention relates to a movie equipment dolly with a chassis, a lifting arm coupled to the chassis, a hydraulic system for lifting the arm, a plurality of steerable wheels, a transmission for orienting the wheels into selected steering modes, a steering system, slip idlers for selectively disconnecting the wheels from the steering system and transmission, and a control handle that has steering, hydraulic system actuation and transmission steering mode selection operations on a common handle, so that the operator need not remove his or her hands from the control handle when performing any of the operations. The movie dolly also has a levelling head coupled to the lifting arm which allows simple, simultaneous orientation of the levelling head roll and pitch axes by manipulating a pair of adjusters. | 1 |
BACKGROUND
[0001] 1. Field of Invention
[0002] The present invention relates generally to a sealed container with an opening means enclosed within the container for releasing a fluid enclosed within the container.
[0003] 2. Description of Related Art
[0004] A variety of opening means exists for opening a container. Most opening means are in the form of a screw-on cap or a snap-on cap. Some opening means are in the form of a frangible seal or a score line on the container that will allow the contents of the container to be released upon fracturing of the frangible seal or the container at the score line. All of these opening means are either attached to the container externally, such as the screw-on cap and the snap-on cap, or are formed as part of the container, such as the frangible seal and the score line on the container. None of the opening means are designed to be enclosed within the container to seal a liquid in the container and yet still allow the release of the liquids easily and reliably. The availability of an effective and easy to use opening means is particularly lacking for a small elongated container with a small cross-sectional area.
BRIEF SUMMARY OF THE INVENTION
[0005] A container with push-pull opening means comprising an axially extendable and compressible elongated housing enclosing a fluid therein and with an enclosed opening means therein sealing the fluid in the elongated housing. The enclosed opening means is operated by stretching or compressing the elongated housing to open and close the enclosed opening means. In the preferred embodiment, the enclosed opening means comprises of a hollow tube with an applicator tip affixed to one end and an operable plug at the other end sealing one or more fluid flow path from the fluid within the elongated housing to the applicator tip.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 shows the preferred embodiment of the container with push-pull opening means in the closed position.
[0007] FIG. 2 shows another embodiment of the container with push-pull opening means.
[0008] FIG. 3 shows the preferred embodiment of the container with push-pull opening means in the open position after the elongated housing is stretched axially.
[0009] FIG. 4 shows the preferred embodiment of the container with push-pull opening means in the open position after the elongated housing is compressed axially.
[0010] FIG. 5 shows another embodiment of the container with push-pull opening means.
[0011] FIG. 6 shows another embodiment of the container with push-pull opening means.
[0012] FIG. 7 shows another embodiment of the container with push-pull opening means.
[0013] FIG. 8 shows another embodiment of the container with push-pull opening means.
[0014] FIG. 9 shows another embodiment of the container with push-pull opening means.
[0015] FIG. 10 shows another embodiment of the container with push-pull opening means.
[0016] FIG. 11 shows another embodiment of the container with push-pull opening means.
[0017] FIG. 12 shows another embodiment of the container with push-pull opening means.
[0018] FIG. 13 shows another embodiment of the container with push-pull opening means.
[0019] FIG. 14 shows another embodiment of the container with push-pull opening means.
[0020] FIG. 15 shows another embodiment of the container with push-pull opening means.
[0021] FIG. 16 shows another embodiment of the container with push-pull opening means.
[0022] FIG. 17 shows another embodiment of the container with push-pull opening means.
[0023] FIG. 18 shows another embodiment of the container with push-pull opening means.
[0024] FIG. 19 shows another embodiment of the container with push-pull opening means.
[0025] FIG. 20 shows another embodiment of the container with push-pull opening means.
[0026] FIG. 21 shows another embodiment of the container with push-pull opening means.
[0027] FIG. 22 shows another embodiment of the container with push-pull opening means.
[0028] FIG. 23 shows another embodiment of the container with push-pull opening means.
[0029] FIG. 24 shows another embodiment of the container with push-pull opening means.
[0030] FIG. 25 shows another embodiment of the container with push-pull opening means.
[0031] FIG. 26 shows another embodiment of the container with push-pull opening means.
[0032] FIG. 27 shows another embodiment of the container with push-pull opening means.
[0033] FIG. 28 shows another embodiment of the container with push-pull opening means.
[0034] FIG. 29 shows another embodiment of the container with push-pull opening means.
[0035] FIG. 30 shows another embodiment of the container with push-pull opening means.
[0036] FIG. 31 shows another embodiment of the container with push-pull opening means.
[0037] FIG. 32 shows another embodiment of the container with push-pull opening means.
[0038] FIG. 33 shows another embodiment of the container with push-pull opening means.
[0039] FIG. 34 shows another embodiment of the container with push-pull opening means.
[0040] FIG. 35 shows another embodiment of the container with push-pull opening means.
[0041] FIG. 36 shows another embodiment of the container with push-pull opening means.
[0042] FIG. 37 shows another embodiment of the container with push-pull opening means.
[0043] FIG. 38 shows another embodiment of the container with push-pull opening means.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0044] The following description and figures are meant to be illustrative only and not limiting. Other embodiments of this invention will be apparent to those of ordinary skill in the art in view of this description.
[0045] FIGS. 1, 2 , 3 , and 4 show the current preferred embodiment of the present invention. In the preferred embodiment, the container with push-pull opening means comprises of an elongated tubular housing 1 with a bellow section 2 between its two ends that can be stretched and compressed by pulling or pushing the elongated tubular housing 1 on either side of the bellow section 2 . A fluid 3 is disposed inside the elongated tubular housing 1 . One end of the elongated tubular housing is sealed and a hollow tube 4 with a sealed end and an open end is affixed at the other end of the elongated tubular housing 1 with the sealed end inside the elongated tubular housing 1 . An applicator tip 5 such as a cotton swab or a foam material may be affixed to the open end of the hollow tube 4 . An opening 6 such as a hole is formed on the cylindrical surface near the sealed end of the hollow tube 4 . A sealing plug 7 in the form similar to an o-ring is disposed around the hollow tube 4 sealing the opening 6 . The bellow section 2 is positioned between the sealing plug 7 and the open end of the hollow tube 4 . In one embodiment, the sealing plug 7 may be slidable inside the elongated tubular housing 1 along the length of the hollow tube 4 , opening and closing the opening 6 on the hollow tube 4 , by squeezing the elongated tubular housing 1 at the position of the sealing plug 7 thereby affix the position of the sealing plug 7 relative to the elongated tubular housing 1 and pulling or pushing the elongated tubular housing 1 on either side of the bellow section 2 . In another embodiment, the sealing plug 7 may be affixed to the elongated tubular housing 1 and slidable along the hollow tube 4 when the elongated tubular housing 1 is stretched or compressed.
[0046] As shown in FIG. 3 , when the elongated tubular housing 1 is stretched, the hollow tube 4 will be pulled away from the sealing plug 7 thereby exposing the opening 6 near its sealed end. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the resulting opening in the sealing plug 7 , into the opening 6 in the hollow tube 4 , and out through the hollow tube 4 into the applicator tip 5 by squeezing the elongated tubular housing 1 . The opening means may also be operated by compressing the bellow section 2 as shown in FIG. 4 , wherein the sealed end of the hollow tube 4 will be urged towards the fluid 3 and the opening 6 near the sealed end will be exposed. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the opening 6 near the sealed end of the hollow tube 4 and through the hollow tube 4 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0047] FIG. 2 shows a variation of the preferred embodiment of the present invention. In this embodiment, the opening 6 in the hollow tube 4 is positioned away from the sealed end of the hollow tube 4 wherein the opening 6 is position away from the sealing plug 7 and opposite of the fluid 3 in the elongated tubular housing 1 . In this embodiment, when the elongated tubular housing 1 is stretched, the hollow tube 4 will be pulled away from the sealing plug 7 thereby exposing the opening 6 to the fluid 3 . The fluid 3 enclosed within the elongated tubular housing 1 is then released through the resulting opening in the sealing plug 7 , into the opening 6 in the hollow tube 4 , and out through the hollow tube 4 into the applicator tip 5 .
[0048] In another embodiment, the sealed end of the hollow tube 4 has an enlarged section 8 that is greater than the opening in the sealing plug 7 as shown in FIG. 5 . In this configuration, when the elongated tubular housing 1 is compressed, the sealed end of the hollow tube 4 will be urged towards the fluid 3 and the opening 6 near the sealed end will be exposed. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the opening 6 near the sealed end of the hollow tube 4 and through the hollow tube 4 into the applicator tip 5 by squeezing the elongated tubular housing 1 . When the elongated tubular housing 1 is stretched back to its initial position, the enlarged section 8 at the sealed end of the hollow tube 4 will stop the travel of the hollow tube 4 at a position that enable the sealing plug 7 to positively re-seal the opening 6 on the hollow tube 4 thereby allow repeated opening and closing of the container.
[0049] FIG. 6 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 9 is in the form of a cup or a short section of a tube with a sealed end and an open end. The sealing plug 9 is removably affixed to the sealed end of the hollow tube 4 sealing the opening 6 near the sealed end of the hollow tube 4 . In one embodiment, the sealing plug 9 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . The sealing plug 9 is removed by squeezing the elongated tubular housing 1 at the position of the sealing plug 9 thereby affix the position of the sealing plug 9 relative to the elongated tubular housing 1 and pulling the elongated tubular housing 1 on either side of the bellow section 2 . In another embodiment, the sealing plug 9 may be affixed to the wall of the elongated tubular housing 1 and provided with fluid flow path from one side of the sealing plug 9 to the other side such as that shown in FIG. 8 . When the elongated tubular housing 1 is stretched, the hollow tube 4 will be pulled away from the sealing plug 9 thereby exposing the opening 6 near its sealed end. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the opening 6 in the hollow tube 4 and out through the hollow tube 4 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0050] The embodiment shown in FIG. 6 may also be provided with a snap-open safety feature wherein the sealing plug 9 is provided with a fracture line on the wall of the sealing plug 9 positioned above the opening 6 near the sealed end of the hollow tube 4 when the sealing plug 9 is placed over the sealed end of the hollow tube 4 . The open end of the sealing plug 9 is affixed to the hollow tube 4 above the fracture line. In this configuration, the sealing plug 9 cannot be pulled away from the hollow tube 4 by accident. The elongated tubular housing 1 must first be bent at the fracture line on the sealing plug 9 to separate the sealing plug 9 at the fracture line into two portions, a top portion that is affixed to the hollow tube 4 and a bottom portion that seals the opening 6 near the sealed end of the hollow tube 4 . The bottom portion may then be pulled away from the hollow tube 4 to expose the opening 6 near the sealed end and allow the fluid 3 to be released through the opening 6 .
[0051] Another embodiment of the container with push-pull opening means is shown in FIG. 7 . In this embodiment, the container with push-pull opening means comprises of an elongated tubular housing 1 with a bellow section 2 between its two ends that can be stretched and compressed by pulling or pushing the elongated tubular housing 1 on either side of the bellow section 2 . A fluid 3 is disposed inside the elongated tubular housing 1 . One end of the elongated tubular housing 1 is sealed and a hollow tube 10 is affixed at the other end of the elongated tubular housing 1 with an applicator tip 5 such as a cotton swab or a foam material affixed to the end of the hollow tube 10 outside of the elongated tubular housing 1 . The sealing plug 9 is in the form of a cup or a short section of a tube with a sealed end and an open end. The sealing plug 9 is removably affixed to the end of the hollow tube 10 enclosed in the elongated tubular housing 1 thereby sealing the open end. In one embodiment, the sealing plug 9 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . The sealing plug 9 is removed by squeezing the elongated tubular housing 1 at the position of the sealing plug 9 thereby affix the position of the sealing plug 9 relative to the elongated tubular housing 1 and then pulling the elongated tubular housing 1 on either side of the bellow section 2 . In another embodiment, the sealing plug 12 may be affixed to the wall of the elongated tubular housing 1 and provided with fluid flow path from one side of the sealing plug 12 to the other side such as that shown in FIG. 8 . When the elongated tubular housing 1 is stretched, the hollow tube 10 will be pulled away from the sealing plug 12 thereby exposing its open end. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the open end of the hollow tube 10 and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0052] The embodiment shown in FIG. 7 may also be provided with a snap-open safety feature wherein the sealing plug 9 is provided with a fracture line 11 on the wall of the sealing plug 9 positioned above the open end of the hollow tube 10 when the sealing plug 9 is placed over the open end of the hollow tube 10 . The open end of the sealing plug 9 is affixed to the hollow tube 10 above the fracture line 11 . In this configuration, the sealing plug 9 cannot be pulled away from the hollow tube 10 by accident. The elongated tubular housing 1 must first be bent at the fracture line 11 on the sealing plug 9 to separate the sealing plug 9 at the fracture line 11 into two portions, a top portion that is affixed to the hollow tube 10 and a bottom portion that seals the open end of the hollow tube 10 . The bottom portion may then be pulled away from the hollow tube 10 to expose the open end and allow the fluid 3 to be released through the open end of the hollow tube 10 .
[0053] FIG. 9 shows another embodiment of the container with push-pull opening means. In this embodiment, the container with push-pull opening means comprises of an elongated tubular housing 1 with a bellow section 2 between its two ends that can be stretched and compressed by pulling or pushing the elongated tubular housing 1 on either side of the bellow section 2 . A fluid 3 is disposed inside the elongated tubular housing 1 . One end of the elongated tubular housing 1 is sealed and a hollow tube 10 is affixed at the other end of the elongated tubular housing 1 with an applicator tip 5 such as a cotton swab or a foam material affixed to the end of the hollow tube 10 outside of the elongated tubular housing 1 . The sealing plug 13 is in the form of a cup or a short section of a tube with a sealed end and an open end. An opening 14 is provided on the wall of the sealing plug 13 near the sealed end. The sealing plug 13 is removably affixed to the end of the hollow tube 10 sealing the open end of the hollow tube 10 . In one embodiment, the sealing plug 13 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . The sealing plug 13 is urged to slide away from the open end of the hollow tube 10 by squeezing the elongated tubular housing 1 at the position of the sealing plug 13 thereby affix the position of the sealing plug 13 relative to the elongated tubular housing 1 and pulling the elongated tubular housing 1 on either side of the bellow section 2 . When the opening 14 in the wall of the sealing plug 13 slides past the end of the hollow tube 10 , a fluid flow path is exposed and the fluid 3 within the elongated tubular housing 1 may be released. The sealing plug 13 may remain at the end of the hollow tube 10 without obstructing the fluid flow path.
[0054] The embodiment shown in FIG. 9 may also be provided with a snap-open safety feature wherein the hollow tube 10 is provided with a fracture line on the wall of the hollow tube 10 positioned above the open end of the hollow tube 10 with the end of the hollow tube 10 affixed to the sealing plug 13 . In this configuration, the sealing plug 13 cannot be pulled away from the hollow tube 10 by accident. The elongated tubular housing 1 must first be bent at the fracture line on the hollow tube 10 to separate the end of the hollow tube 10 that is affixed to the sealing plug 13 from the remainder of the hollow tube 10 . The sealing plug 13 may then be pulled away from the hollow tube 10 to expose a fluid flow path through the opening 14 in the sealing plug 13 through the fractured open end of the hollow tube 10 and allow the fluid 3 to be released.
[0055] FIG. 10 shows another embodiment of the container with push-pull opening means. In this embodiment, the container with push-pull opening means comprises of an elongated tubular housing 1 with a bellow section 2 between its two ends that can be stretched and compressed by pulling or pushing the elongated tubular housing 1 on either side of the bellow section 2 . A fluid 3 is disposed inside the elongated tubular housing 1 . One end of the elongated tubular housing 1 is sealed and a hollow tube 10 is affixed at the other end of the elongated tubular housing 1 with an applicator tip 5 such as a cotton swab or a foam material affixed to the end of the hollow tube 10 outside of the elongated tubular housing 1 . The sealing plug 9 is in the form of a cup or a short section of a tube with a sealed end and an open end. The sealing plug 9 is removably affixed to the open end of the hollow tube 10 sealing the end of the hollow tube 10 . The sealing plug 9 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . A restriction 15 is affixed to the elongated tubular housing 1 above the sealing plug 9 wherein the sealing plug 9 is removed by simply pulling the elongated tubular housing 1 on either side of the bellow section 2 . The sealing plug 9 will be pulled away from the open end of the hollow tube 10 due to the resistance of the restriction 15 affixed to the elongated tubular housing 1 thereby exposing the open end of the hollow tube 10 . The fluid 3 enclosed within the elongated tubular housing 1 is then released through the open end of the hollow tube 10 and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0056] FIG. 11 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 16 is provided with a protrusion 17 with approximately the same outside diameter as the inside diameter of the hollow tube 10 . The protrusion 17 on the sealing plug 16 is inserted into the open end of the hollow tube 10 thereby sealing the end of the hollow tube 10 . When the sealing plug 16 is removed from the end of the hollow tube 10 by pulling the elongated tubular housing 1 as disclosed herein, a fluid flow path is exposed through the open end of the hollow tube 10 .
[0057] FIG. 12 shows a variation of the container with push-pull opening means shown in FIG. 11 . In this embodiment, the body of the sealing plug 18 is affixed to the elongated tubular housing 1 and provided with fluid flow path 19 from one side of the sealing plug 18 to the other side. When the elongated tubular housing 1 is stretched, the hollow tube 10 will be pulled away from the sealing plug 18 thereby exposing its open end. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the open end of the hollow tube 10 and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0058] FIG. 13 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 20 is in the form of a cup or a short section of a tube with a sealed end and an open end wherein the open end has approximately the same inside diameter as the outside diameter of the hollow tube 10 . An opening 21 is provided on the wall of the sealing plug 20 that is obstructed by the hollow tube 10 when the sealing plug 20 is placed over the end of the hollow tube 10 . In the center of the sealing plug 20 is a protrusion 22 with approximately the same outside diameter as the inside diameter of the hollow tube 10 and is shorter than the wall of the sealing plug 20 . When the sealing plug 20 is pulled away from the hollow tube 10 , the opening 21 in the wall of the sealing plug 20 and the open end of the hollow tube 10 will form a fluid flow path for the fluid 3 in the elongated tubular housing 1 to be released. The sealing plug 20 may remain at the end of the hollow tube 10 without obstructing the fluid flow path.
[0059] FIG. 14 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 16 is provided with a protrusion 17 with approximately the same outside diameter as the inside diameter of the hollow tube 10 . The protrusion 17 on the sealing plug 16 is inserted into the open end of the hollow tube 10 thereby sealing the end of the hollow tube 10 . The body of the sealing plug 16 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . A restriction 23 is affixed to the elongated tubular housing 1 above the sealing plug 16 wherein the sealing plug 16 is removed by simply pulling the elongated tubular housing 1 on either side of the bellow section 2 . The sealing plug 16 will be pulled away from the open end of the hollow tube 10 due to the resistance of the restriction 23 affixed to the elongated tubular housing 1 thereby exposing the open end of the hollow tube 10 . The fluid 3 enclosed within the elongated tubular housing 1 is then released through the open end of the hollow tube 10 and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0060] The embodiment shown in FIG. 12 may also be provided with a snap-open safety feature as shown in FIG. 15 wherein the hollow tube 10 is provided with a fracture line 24 positioned at the protrusion of the sealing plug 18 when the protrusion is inserted into the hollow tube 10 . The open end of the hollow tube 10 is affixed to the body of the sealing plug 18 at a position below the fracture line 24 . In this configuration, the sealing plug 18 cannot be pulled away from the hollow tube 10 by accident. The elongated tubular housing 1 must first be bent at the fracture line 24 on the hollow tube 10 to separate the hollow tube 10 and the sealing plug 18 at the fracture line 24 . The sealing plug 18 may then be pulled away from the hollow tube 10 to expose the open end of the hollow tube 10 and to allow the fluid 3 to be released through the opening. In a variation of this embodiment, the body of the sealing plug 18 may affixed to the elongated tubular housing 1 and provided with fluid flow path 19 from one side of the sealing plug 18 to the other side.
[0061] Another embodiment of the container with push-pull opening means is shown in FIGS. 16 and 17 . In this embodiment, the sealing plug 25 has a hollow body with a sealed end and an open end. An opening 26 is disposed near the sealed end of the sealing plug 25 . The sealing plug 25 is inserted with its sealed end into the hollow tube 10 . The opening 26 near the sealed end of the sealing plug 25 may be inside the hollow tube 10 as shown in FIG. 16 or outside of the hollow tube 10 as shown in FIG. 17 . When the elongated tubular housing 1 is stretched, the hollow tube 10 will be pulled away from the sealing plug 25 thereby exposing its open end. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the opening 26 near the end of the sealing plug 25 , through the open end of the hollow tube 10 , and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0062] Another embodiment of the container with push-pull opening means is shown in FIG. 18 . In this embodiment, the sealing plug 27 is disposed at a restriction 28 in the elongated tubular housing 1 . The restriction 28 has an opening approximately that of the outside diameter of the hollow tube 10 . The sealing plug 27 has approximately the same diameter as the outside diameter of the hollow tube 10 . The open end of the hollow tube 10 is inserted into one end of the restriction 28 in the elongated tubular housing 1 with the sealing plug 27 sealing the fluid flow path through the other end of the restriction 28 . When the elongated tubular housing 1 is compressed, the hollow tube 10 will be urged against the sealing plug 27 and push the sealing plug 27 out of the restriction 28 in the elongated tubular housing 1 thereby exposing a fluid flow path through the restriction 28 and the open end of the hollow tube 10 . The fluid 3 enclosed within the elongated tubular housing 1 is then released through the restriction 28 , through the open end of the hollow tube 10 , and out through the hollow tube 10 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0063] FIG. 19 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 27 is disposed within a cylinder 30 with a sealed end and an open end. The cylinder 30 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 . Multiple openings 31 are formed in the cylindrical walls near the sealed end of the cylinder 30 positioned between the sealing plug 27 and the sealed end of the cylinder 30 . The open end of the cylinder 30 is affixed to and sealed with its outside surface against the elongated tubular housing 1 sealing the fluid 3 near the sealed end of the elongated tubular housing 1 . The open end of the hollow tube 29 is formed at an angle such as by cutting the end of the open end at an angle. The open end with the angle is inserted into the cylinder 30 to just above the sealing plug 27 . When the elongated tubular housing 1 is compressed, the open end of the hollow tube 29 with the angle will urge the sealing plug 27 past the openings 31 in the cylindrical walls thereby exposing a fluid flow path. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the openings 31 in the cylindrical walls through the open end of the hollow tube 29 , and out through the hollow tube 29 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0064] FIG. 20 shows another embodiment of the container with push-pull opening means. In this embodiment, a tubular member 32 with one end affixed to and sealed by the sealed end of the elongated tubular housing 1 is disposed inside the elongated tubular housing 1 . The tubular member 32 extends to, overlaps, and seals against the open end of the hollow tube 10 . The inside diameter of the tubular member 32 at the overlap is approximately that of the outside diameter of the hollow tube 10 . A fluid 3 is sealed between the outside wall of the hollow member 32 /hollow tube 10 and the inside wall of the elongated tubular housing 1 . When the elongated tubular housing 1 is stretched, the tubular member 32 and the hollow tube 10 will separate and the seal between them is broken. The fluid 3 will then be release through the resulting opening at the open end of the hollow tube 10 .
[0065] FIG. 21 shows another embodiment of the container with push-pull opening means. In this embodiment, a tubular member 33 with one end affixed to the sealed end of the elongated tubular housing 1 is disposed inside the elongated tubular housing 1 . An opening 34 is provided on the wall of the tubular member 33 near the sealed end of the elongated tubular housing 1 . The tubular member 33 extends to, overlaps, and seals against a sealed end of the hollow tube 4 . An opening 6 is provided in the cylindrical wall of the hollow tube 4 near the sealed end. The inside diameter of the tubular member 33 at the overlap is approximately that of the outside diameter of the hollow tube 4 . When the elongated tubular housing 1 is stretched, the tubular member 33 and the hollow tube 4 will separate and the seal between them will be broken. The fluid 3 will then be release through the opening 6 in the cylindrical wall near the sealed end of the hollow tube 4 .
[0066] FIG. 22 shows another embodiment of the container with push-pull opening means. In this embodiment, the opening means comprises a first elongated hollow tube 36 with two ends wherein one end has a smaller diameter than the remainder of the first elongated hollow tube 36 . A second elongated hollow tube 35 with two ends wherein one end has a larger diameter than the remainder of the second elongated hollow tube 35 and also larger than the diameter of the end of the first elongated hollow tube 36 with the smaller diameter slidably engaged to the first elongated hollow tube 36 on a common axis with the larger diameter of the second elongated hollow tube 35 disposed inside the smaller diameter end of the first elongated hollow tube 36 . The two elongated hollow tubes 35 , 36 will form a seal at their interface as shown in FIG. 22 . A fluid 3 is sealed between the outside walls of the two elongated hollow tubes 35 , 36 and the inside wall of the elongated tubular housing 1 . In this configuration when the elongated tubular housing 1 is compressed the seal at the interface between the two elongated hollow tubes 35 , 36 will be broken. The fluid 3 enclosed within the elongated tubular housing 1 is then released through the second elongated hollow tube 35 into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0067] FIG. 23 shows another embodiment of the container with push-pull opening means. In this embodiment, a sealing plug 37 is affixed to the end of an elongated member 38 . The sealing plug 37 may also be formed as an integral part of the end of an elongated member 38 . The other end of the elongated member 38 is affixed to the sealed end of the elongated tubular housing 1 . The sealing plug 37 is disposed at a restriction 39 inside the elongated tubular housing 1 thereby sealing the fluid 3 within the elongated tubular housing 1 near the sealed end. When the elongated tubular housing 1 is stretched at the bellow section 2 , the sealing plug 37 will be pulled away from the restriction 39 thereby opening a fluid flow path from the fluid 3 to the hollow tube 10 at the other end of the elongated tubular housing 1 . The fluid 3 enclosed within the elongated tubular housing 1 is then released through the hollow tube 10 and into the applicator tip 5 by squeezing the elongated tubular housing 1 .
[0068] FIG. 24 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 40 is an elongated member with approximately the same outside diameter as the inside diameter of the hollow tube 10 . One end 41 of the elongated member is formed with a profile such that when that end of the elongated member is inserted into the hollow tube 10 it will not seal the fluid flow path from the fluid 3 through the hollow tube 10 . The non-sealing end 41 may have a square, triangular, or any other geometric profile other than a circle with approximately the same diameter as the inside diameter of the hollow tube 10 . The elongated member is inserted with the non-sealing end 41 and a short length of the sealing portion with approximately the same outside diameter as the inside diameter of the hollow tube 10 inside the hollow tube 10 . A length of the elongated member extends outside of the hollow tube such that it may be grasped by squeezing the elongated tubular housing 1 at the position of the elongated member that extends outside of the hollow tube 10 thereby affix the position of the elongated member relative to the elongated tubular housing 1 and pulling the elongated tubular housing 1 on either side of the bellow section 2 . When the elongated member is partially pulled out of the hollow tube 10 such that the non-sealing end is exposed to the fluid 3 , a fluid flow path is exposed to allow the fluid 3 to be release from the elongated tubular housing 1 . The non-sealing end will remain in the hollow tube 10 thereby retain the elongated member at the end of the hollow tube 10 .
[0069] FIG. 25 shows another application of the embodiment of the container with push-pull opening means shown in FIG. 24 . The structure shown in FIG. 24 is inverted and affixed within the elongated tubular housing 1 with the hollow tube 10 sealing against the inside wall of the elongated tubular housing 1 to seal the fluid 3 within the elongated tubular housing 1 . When the elongated member is partially pulled out of the hollow tube 10 such that the non-sealing end is exposed outside of the hollow tube 10 , a fluid flow path is exposed to allow the fluid 3 to be release from the elongated tubular housing 1 . The non-sealing end 41 will remain in the hollow tube 10 thereby retain the elongated member at the end of the hollow tube 10 .
[0070] The embodiments shown in FIGS. 24 and 25 may also be provided with a snap-open safety feature wherein the hollow tube 10 is provided with a fracture line positioned at the sealing portion of the elongated member. The end of the hollow tube 10 with the protruding elongated member is affixed to the elongated member. In this configuration, the elongated member cannot be pulled away from the hollow tube 10 by accident. The elongated tubular housing 1 must first be bent at the fracture line on the hollow tube 10 to separate the hollow tube 10 and the elongated member at the fracture line. The elongated member may then be pulled away from the hollow tube 10 to expose a fluid flow path and to allow the fluid 3 to be released through the fluid flow path.
[0071] FIG. 26 shows another embodiment of the container with push-pull opening means. In this embodiment, the sealing plug 40 is an elongated member with a profile such that when the elongated member is inserted at a restriction 42 in the elongated tubular housing 1 it will not seal the fluid flow path from the fluid 3 through the restriction 42 . The profile may be a square, triangular, or any other geometric profile other than a circle with approximately the same diameter as the inside diameter of the restriction 42 . One end of the elongated member has a sealing profile with approximately the same outside diameter as the inside diameter of the restriction 42 . The elongated member is inserted with the end with the sealing profile and a short length of the elongated member inside the restriction 42 . A length of the elongated member extends outside of the restriction 42 such that it may be grasped by squeezing the elongated tubular housing 1 at the position of the elongated member that extends outside of the restriction 42 thereby affix the position of the elongated member relative to the elongated tubular housing 1 . The elongated member may be urged to move through the restriction 42 by compressing the elongated tubular housing 1 on either side of the bellow section 2 . When the end of the elongated member with the sealing profile is pushed out of the restriction 42 , a fluid flow path is exposed to allow the fluid 3 to be release from the elongated tubular housing 1 . The elongated member will be retained at the restriction 42 .
[0072] FIG. 27 shows a variation of the container with push-pull opening means shown in FIG. 26 . In this embodiment, an opening 44 is provided on the cylindrical wall of a hollow tube 43 on the side of the end of the elongated member with the sealing profile opposite the fluid 3 . The hollow tube 43 has a smaller outside diameter than the inside diameter of the elongated tubular housing 1 and is sealed against the elongated tubular housing 1 at the end of the hollow tube 43 with the protruding elongated member. When the elongated tubular housing 1 is compressed, the end of the elongated member with the sealing profile will slide past the opening 44 in the cylindrical wall of the hollow tube 43 and expose a fluid flow path from the fluid 3 through the side of the elongated member, through the opening 44 in the cylindrical wall of the hollow tube 43 , through the space between the outside wall of the hollow tube 43 and the inside wall of the elongated tubular housing 1 , and out to the applicator tip 5 .
[0073] FIG. 28 shows a variation of the container with push-pull opening means shown in FIG. 27 . In this embodiment, the end of the hollow tube 45 opposite the protruding elongated member is sealed thereby limiting the travel of the elongated member past the opening 46 in the cylindrical wall of the hollow tube 45 .
[0074] FIG. 29 shows another embodiment of the container with push-pull opening means shown in FIG. 28 . In this embodiment, the hollow tube 47 that is affixed at the end of the elongated tubular housing 1 has a sealed end positioned inside the elongated tubular housing 1 . An elongated member 40 as shown and described in reference to FIGS. 24 through 28 is inserted with the end with the sealing profile into the hollow tube 47 and affixed to the sealed end of the hollow tube 47 . A snap-open safety feature in the form of a fracture line 48 is provided on the hollow tube 47 at the position of the end of the elongated member 40 with the sealing profile. The elongated member 40 cannot be pulled away from the hollow tube 47 by accident. The elongated tubular housing 1 must first be bent at the fracture line 48 on the hollow tube 47 to separate the hollow tube 47 and the elongated member 40 at the fracture line 48 . The elongated member 40 may then be pulled away from the hollow tube 47 to expose a fluid flow path and to allow the fluid 3 to be released through the fluid flow path.
[0075] FIG. 30 shows another application of the embodiment of the container with push-pull opening means shown in FIG. 29 . The structure shown in FIG. 29 is inverted and affixed within the elongated tubular housing 1 with the outside diameter of the open end of the hollow tube 49 sealing against the inside wall of the elongated tubular housing 1 to seal the fluid 3 within the elongated tubular housing 1 . When the elongated tubular housing 1 is bent at the fracture line 50 , the hollow tube 49 will be separated from the elongated member 40 and the elongated member 40 may then be partially pulled out of the hollow tube 49 . When the non-sealing end 41 of the elongated member 40 is exposed outside of the hollow tube 49 , a fluid flow path is exposed to allow the fluid 3 to be released from the elongated tubular housing 1 . The non-sealing end 41 will remain in the hollow tube 49 thereby retain the elongated member 40 at the end of the hollow tube 49 .
[0076] FIG. 31 shows another variation of the embodiment of the container with push-pull opening means shown in FIG. 30 . In this embodiment, the elongated member 51 extends a substantial length out of the open end of the hollow tube 49 . After the elongated tubular housing 1 is bent at the fracture line 50 to separate the hollow tube 49 into two sections, the elongated tubular housing 1 may then be compressed at the bellow section 2 , pushing the non-sealing end 52 of the elongated member 51 into the hollow tube 49 . The sealing end of the elongated member 51 will urge the sealed end of the hollow tube 49 to separate from the remainder of the hollow tube 49 thereby exposing a fluid flow path around the elongated member 51 , through the hollow tube 49 , exit the hollow tube 49 at the fracture 50 , and into the applicator tip 5 .
[0077] FIG. 32 shows another embodiment of the container with push-pull opening means. In this embodiment, a hollow tube 53 with a sealed end is affixed to the end of the elongated tubular housing 1 with the sealed end inside the elongated tubular housing 1 . A plug 54 with a shorter length than the hollow tube 53 is affixed to the sealed end of the hollow tube 53 inside the hollow tube 53 . An opening 55 is provided on the cylindrical wall of the hollow tube 53 at a position along the length of the plug 54 inside the hollow tube 53 . A fracture line 56 is formed on the hollow tube 53 below the opening 55 at a position along the length of the plug 54 inside the hollow tube 53 . When the elongated tubular housing 1 is bent near the fracture line 56 on the hollow tube 53 , the hollow tube 53 will be separated into two sections. The section with the plug 54 attached may then be pulled out of the remainder of the hollow tube 53 to open a fluid flow path through the opening 55 in the cylindrical wall of the hollow tube 53 by stretching the elongated tubular housing 1 at the bellow section 2 .
[0078] FIG. 33 shows another embodiment of the container with push-pull opening means. In this embodiment, the hollow tube 4 with a sealed end is inserted into the elongated tubular housing 1 with its sealed end inside the elongated tubular housing 1 extending into a restriction 57 in the elongated tubular housing 1 . An opening 6 is provided in the cylindrical wall of the hollow tube 4 near the sealed end positioned inside and sealed by the restriction 57 . The seal end of the hollow tube 4 is further provided with a protrusion 58 extending away from the sealed end with a profile such that when that protrusion 58 is inserted into the restriction 57 in the elongated tubular housing 1 it will not seal the fluid flow path from the fluid 3 through the restriction 57 . The protrusion 58 may have a square, triangular, or any other geometric profile other than a circle with approximately the same diameter as the inside diameter of the restriction 57 . In this embodiment, when the elongated tubular housing 1 is stretched at the bellow section 2 , the hollow tube 4 will be pulled away from the restriction 57 . When the opening 6 in the cylindrical wall of the hollow tube 4 is exposed outside of the restriction 57 , a fluid flow path will be opened. The fluid 3 may then be released through the opening between the protrusion 58 and the restriction 57 , out of the restriction 57 , into the opening 6 in the cylindrical wall of the hollow tube 4 , and out of the hollow tube 4 .
[0079] The restriction 57 in the elongated tubular housing 1 may be in the form of a sealing plug. The sealing plug may be affixed to the wall of the elongated tubular housing 1 and provided with fluid flow path from one side of the sealing plug to the other side such as that shown in FIG. 8 . The hollow tube 4 shown in FIG. 33 may also be sealed and affixed to the sealing plug at a location between the opening 6 in the cylindrical wall of the hollow tube 4 and the open end of the hollow tube 4 with the opening 6 disposed within the sealing plug. A fracture line is provided on the circumference of the sealing plug at a position between the opening 6 and where the hollow tube 4 is sealed and affixed to the sealing plug. With this embodiment, the sealing plug must first be separated into two sections at the fracture line by bending the elongated tubular housing 1 at the location of the fracture line before the hollow tube 4 maybe pulled out of the sealing plug by stretching the elongated tubular housing 1 at the bellow section 2 .
[0080] FIG. 34 shows another embodiment of the container with push-pull opening means. In this embodiment, a first hollow tube 59 with a thru bore and an outside dimension at one end 60 that is smaller than the inside diameter of a second hollow tube 61 with a sealed end is inserted into and affixed with the smaller end 60 to the sealed end of the second hollow tube 61 . A fracture line 62 is provided around the circumference at the smaller end 60 . After the elongated tubular housing 1 is bent at the location of the fracture line 62 , the two hollow tubes 59 , 61 may be pulled apart by stretching the elongated tubular housing 1 at the bellow section 2 . When the smaller end 60 of the first hollow tube 59 is revealed outside of the second hollow tube 61 , a fluid flow path is opened through the thru bore in the first hollow tube 59 .
[0081] If the first hollow tube 59 is not affixed to the second hollow tube 61 , the first hollow tube 59 must have a sealing outside diameter approximately that of the inside diameter of the second hollow tube 61 such that when it is inserted into the second hollow tube 61 , it will seal the fluid flow path between the two hollow tubes 59 , 61 . The two hollow tubes 59 , 61 may be pulled apart by stretching the elongated tubular housing 1 at the bellow section 2 . When the smaller end 60 of the first hollow tube 59 is revealed outside of the second hollow tube 61 , a fluid flow path is opened through the thru bore in the first hollow tube 59 . In a variation of this embodiment, the first hollow tube 59 may be sealed against and affixed to the second hollow tube 61 near the open end of the second hollow tube 61 and provided with a fracture line on the second hollow tube 61 between the open end of the second hollow tube 61 and the smaller end 60 of the first hollow tube 59 . In this variation, after the two hollow tubes 59 , 61 are separated at the fracture line, the sealed end of the second hollow tube 61 may be pulled away from the first hollow tube 59 to open a fluid flow path.
[0082] FIG. 35 shows another embodiment of the container with push-pull opening means. In this embodiment, an elongated member 63 is inserted into a restriction 64 inside the elongated tubular housing 1 and extends toward the open end of the elongated tubular housing 1 . When one squeezes the elongated tubular housing 1 at the position of the elongated member 63 and grasps both the elongated tubular housing 1 and the elongated member 63 , the elongated member 63 may be pulled away from the restriction 64 in the elongated tubular housing 1 by stretching the elongated tubular housing 1 at the bellow section 2 and open a fluid flow path through the restriction 64 in the elongated tubular housing 1 .
[0083] FIG. 36 shows another embodiment of the container with push-pull opening means. In this embodiment, two restrictions 64 , 67 are provided inside the elongated tubular housing 1 with one on either side of the bellow section 2 . The restriction 67 near the open end of the elongated tubular housing 1 is provided with one or more fluid flow paths 68 through it such as that shown in FIG. 8 . A hollow tube 65 with a sealed end is inserted with its open end towards the sealed end of the elongated tubular housing 1 through both of the restrictions 64 , 67 in the elongated tubular housing 1 and is affixed to the restriction 67 near the open end of the elongated tubular housing 1 . An opening 66 is formed in the cylindrical wall of the hollow tube 65 near the open end of the hollow tube 65 and positioned at the restriction 64 such that the restriction 64 will seal the opening 66 in the hollow tube 65 . When the elongated tubular housing 1 is stretched at the bellow section 2 , the hollow tube 65 will be pulled away from the restriction 64 near the sealed end of the elongated tubular housing 1 opening a fluid flow path. The fluid 3 may then be released through the open end of the hollow tube 65 , through the opening 66 in the hollow tube 65 , through the fluid flow path 68 through the restriction 67 near the open end of the elongated tubular housing 1 , and into the applicator tip 5 .
[0084] FIG. 37 shows a variation of the container with push-pull opening means shown in FIG. 36 . In this embodiment, the opening 66 in the hollow tube 65 is positioned between the two restrictions 64 , 69 in the elongated tubular housing 1 and no fluid flow path is provided through the restriction 69 near the open end of the elongated tubular housing 1 . When the elongated tubular housing 1 is stretched such that the sealed end of the hollow tube 65 passes the restriction 69 near the open end of the elongated tubular housing 1 , a fluid flow path is opened to release the fluid 3 . The fluid 3 is released through the open end of the hollow tube 65 , out of the opening 66 in the hollow tube 65 , and out of the open end of the elongated tubular housing 1 .
[0085] FIG. 38 shows another embodiment of the container with push-pull opening means. In this embodiment, two restrictions 64 , 67 are provided inside the elongated tubular housing 1 with one on either side of the bellow section 2 . The restriction 67 near the sealed end of the elongated tubular housing 1 is provided with one or more fluid flow paths 68 through it such as that shown in FIG. 8 . A hollow tube 65 with a sealed end is inserted with its open end towards the sealed end of the elongated tubular housing 1 through both of the restrictions 64 , 67 in the elongated tubular housing 1 . An opening 66 is formed in the cylindrical wall of the hollow tube 65 and positioned between the restriction 64 near the open end of the elongated tubular housing 1 and the open end of the elongated tubular housing 1 . A plug 70 in the form of a short section of a tube with a sealed end is placed over the open end of the hollow tube 65 sealing the open end. The plug 70 is affixed to the restriction 67 near the sealed end of the elongated tubular housing 1 . When the elongated tubular housing 1 is stretched at the bellow section 2 , the plug 70 will be pulled away from the hollow tube 65 thereby opening a fluid flow path. The fluid 3 may then be released through the open end of the hollow tube 65 , through the opening 66 in the hollow tube 65 , and into the applicator tip 5 .
[0086] A variation of the container with push-pull opening means shown in FIG. 38 affixes the open end of the plug 70 to the outside wall of the hollow tube 65 with a fracture line 71 provided between where the plug 70 is affixed to the hollow tube 65 and the sealed end of the plug 70 . In this embodiment, when the fracture line 71 is broken open by bending the elongated tubular housing 1 , the plug 70 may be separated from the open end of the hollow tube 65 by stretching the elongated tubular housing 1 at the bellow section 2 . Without fracturing the fracture line 71 , the plug 70 cannot be removed.
[0087] FIG. 39 shows another embodiment of the container with push-pull opening means. In this embodiment, two restrictions 64 , 67 are provided inside the elongated tubular housing 1 with one on either side of the bellow section 2 . The restriction 67 near the sealed end of the elongated tubular housing 1 is provided with one or more fluid flow paths 68 through it such as that shown in FIG. 8 . A hollow tube 65 with a sealed end is inserted with its open end towards the sealed end of the elongated tubular housing 1 through both of the restrictions 64 , 67 in the elongated tubular housing 1 . An opening 66 is formed in the cylindrical wall of the hollow tube 65 and positioned between the restriction 64 near the open end of the elongated tubular housing 1 and the open end of the elongated tubular housing 1 . A plug 72 in the form of a short section of a tube with a sealed end and a protrusion 73 inside the plug 72 at the sealed end is placed over the open end of the hollow tube 65 sealing the open end. The protrusion 73 has approximately the same outside diameter as the inside diameter of the hollow tube 65 and ends with a section 74 that has a smaller profile than the inside diameter of the hollow tube 65 . The plug 72 is affixed to the restriction 67 near the sealed end of the elongated tubular housing 1 . When the elongated tubular housing 1 is stretched at the bellow section 2 , the plug 72 will be pulled away from the hollow tube 65 thereby opening a fluid flow path. The fluid 3 may then be released through the open end of the hollow tube 65 , through the opening 66 in the hollow tube 65 , and into the applicator tip 5 .
[0088] A variation of the container with push-pull opening means shown in FIG. 39 affixes the open end of the plug 72 to the outside wall of the hollow tube 65 with a fracture line 75 provided between where the plug 72 is affixed to the hollow tube 65 and the sealed end of the plug 72 . In this embodiment, when the fracture line 75 is broken open by bending the elongated tubular housing 1 , the plug 72 may be separated from the open end of the hollow tube 65 by stretching the elongated tubular housing 1 at the bellow section 2 . Without fracturing the fracture line 75 , the plug 72 cannot be removed.
[0089] Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. | A container with push-pull opening means comprising an axially extendable and compressible elongated housing enclosing a fluid therein and with an enclosed opening means therein sealing the fluid in the elongated housing. The enclosed opening means is operated by stretching or compressing the elongated housing to open and close the enclosed opening means and comprises of a hollow tube with an applicator tip affixed to one end and an operable plug at the other end sealing one or more fluid flow path from the fluid within the elongated housing to the applicator tip. | 1 |
This application is a divisional of application Ser. No. 07/733,559, filed Jul. 22, 1991, now U.S. Pat. No. 5,304,032.
BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION
Efficiency of rotating aircraft turbine engines (as opposed to reciprocating) depends partially on the efficient air compressor section which, in turn, depends on the clearance control between blade tips and the adjacent surfaces. The analogy would be the fit up and clearance of a piston ring and cylinder wall for an efficient compression stroke.
Because of the close assembly tolerances and the thermal expansion of the parts, a close clearance is maintained by having an abradable material opposite the tips of the blades. The blades cut their own groove or path, thereby minimizing leakage of air around the tips of the blades. Each engine has rows of moving blades mounted on rotating disks with rows of stationary blades in between each rotation section to redirect the flow into the next rotating stage. The stationary blade tips cut their groove into the rotating seal attached to the rotating compressor disk.
The performance of the abradable seal material is such that while it must be abradable and not abrade the tips Of the blades, it cannot stick to the blades. It must also be able to stand the elevated temperature due to compression as well as the erosion of abrasive particles injected into the intake air. The dynamic seal material must also have excellent bond strength to withstand the centrifugal forces induced at 30 to 40,000 rpm. Moreover, when the unit is stopped and parts are in contact, a lower coefficient of friction would facilitate starting by reducing drag forces at the interfaces of the seal material and blade tips.
In titanium bladed auxiliary power units (A.P.U.) a problem exists that when the unit remains stationary, particularly in humid and/or salty atmospheres, the titanium blades tend to seize against the abradable seal. This is because the abradable seal material is about 85% aluminum, or aluminum bronze, which are very much apart on the anodic chart with titanium and hence there is accelerated galvanic-type erosion of the aluminum alloy causing a seizing at the seal interface. The solution appeared to be in a non-metallic abradable seal material.
The present commercial system that has been widely accepted by tile aerospace industry is a system which calls for thermal spraying a mixture of aluminum powder and resin (85% aluminum and 15% resin). The process includes grit blasting the surface, applying a bond coat by thermal spray for better adhesion, then thermal (plasma) spraying the aluminum or aluminum bronze powder, machining this deposit to dimensional requirements, then a seal coat of a resin is applied to impregnate the sprayed deposit. Because the spray process must spray the aluminum powder and resin separately into the plasma, there at at least 15 variables and Taguchi Statistical Process Control methods are constantly applied every time some of these variables are changed.
In other similar systems, the material is also an aluminum or aluminum bronze spray powder with a polyimide powder rather than a polyester powder. None of the versions address the galvanic problem.
A polytetrafluoroethylene (a synthetic resin polymer, solid lubricant) coating is placed over a high temperature resin microsphere mix after the substrate has been machined to allow a coating of 5 mils to be added to the surface. This type of abradable seal solved many of the above problems. However, if the polytetrafluoroethylene particles on the surface were fully nucleated or melted together rather than just sintered, the coating in the thicker areas would tend to peel rather than abrade. Moreover, due to the dimensional tolerances, and difficulty and economics of applying a thick (0.003" or over) coating of polytetrafluoroethylene, it was more realistic to assume that the wear of the blade tips would penetrate into substrate.
In a preferred embodiment of the invention, the tetrafluoroethylene coating is eliminated and solid lubricant polytetrafluoroethylene is incorporated into the microsphere and high temperature resin mix.
From wear tests and metallographic examinations of the surfaces, it appears that some of the polytetrafluoroethyiene or solid lubricant particles embedded in the resin break loose and are trapped in the cavities, nooks and crannies of the microspheres on the surface, thus producing a lower friction force. The friability and the frangibility of this system enables the wear to take place in the abradable seal material without wear or adherence to the titanium blade tips. This system has about 1/3 the variables that are in the present system and does not require the use of an expensive plasma or high velocity thermal spray system and associated equipment.
In a further preferred embodiment, ceramic fibers are incorporated into the resin, microspheres, polytetrafluoroethylene mix.
The basic objectives of the invention are to provide an improved abradable seal for rotating turbine engines and a method of producing same.
DESCRIPTION OF THE DRAWINGS
The above and other objects, advantages and features of the invention will become more apparent when considered with the following specification and attached drawings wherein:
FIG. 1 is a section through one stage of a turbine engine,
FIG. 2 is a section through the abradable seal on the stationary ring, and
FIG. 3 is a section through the abradable seal on the rotating compressor disc.
DETAILED DESCRIPTION OF THE INVENTION
A diagrammatic illustration of the abradable seals of a rotating aircraft turbine engine is shown in FIG. 1. The efficiency depends partially on an efficient air compressor section which, in turn, depends on the clearance control between rotating blade tips BT and adjacent stationary surfaces SC. Because of close assembly tolerances and thermal expansion of parts, a close clearance is maintained by having an abradable material opposite the tips of the blades on the adjacent surfaces so that the blades cut their own groove or path to thereby minimize leakage of air around the blade tips and thus enhance the efficiency.
Referring collectively to FIGS. 1, 2, and 3, a stage portion 10 of a air compressor section of a multistage turbine engine has a fixed housing 11, a shaft 12 carrying rotatable compressor rotor discs 13 having outwardly extending blades (which may be titanium or other compressor blade alloy), and an abradable seal ring 15 on rotating compressor disc ring 16. The tips 17 of rotor blades 14 engage stationary abradable seal ring 18 formed on the interior of housing 11 adjacent stationary blades 19 which are secured to housing 11 and have tips 20 which engage rotating abradable seal ring 15.
According to this invention, the abradable seal surfaces 15 and 18 are provided with a coating comprised of a mixture of polytetrafluoroethylene, hollow-microspheres of ceramic or glass and a high temperature resin (RTM). To form the seals 15 and 18, some of the polytetrafluoroethylene particles embedded in the resin break loose and are trapped in the cavities, nooks and undercuts of fractured microspheres on the surface to produce a lower friction non-galvanic surface. The friability and frangibility of this system enables the wear to take place in the seal material without wear or adherence to the blade tips, which may be titanium.
The high temperature resin has the character of gray viscous plaste polytetrafluoroethylene is a white powder and the microspheres are free flowing.
In a further preferred embodiment, ceramic fibers, which a needle-like pieces of ceramic 1/8" to 100 microns long, are incorporated into the high temperature resin, microsphere and polytetrafluoroethylene mix for additional strength especially in order to withstand the hoop stresses induced by the high rotational speeds of the compressor disks.
The use of a thermo-set resin, using a hardener, makes use of epoxy and polyamide-imide materials that have a high glass transition temperature (Tg) and a high heat deflection temperature (HDT). These properties are enhanced with the addition of the ceramic fibers, microspheres and polytetrafluoroethylene powders.
The resin, polytetrafluoroethylene and microspheres (RTM) formulation is preferably applied to the turbine's surfaces which have been heated to over 100 degrees Farenheit (125-150 degrees) and kept at that temperature by a hot air blower. The RTM mix should be applied in a manner to prevent folding in or entrapment of air, and an excess of material is added to allow for machining to final dimensions. However, excessive thickness may cause sagging which should be avoided. The parts are preferably rotated to allow major voids to surface and be eliminated, and then cured in an oven (3 hrs. @100 degrees C. and 180 degrees C. for 1 hr.) while the part or parts are rotated at about 6 rpm. At the end of the curing cycle the parts are cooled slowly to at least 70 degrees C. The RTM mix call be thermally sprayed while rotating the part on which the abradable seal is to be formed.
The following ratios of resin to fillers are percentages by weight of a preferred embodiment:
50/35 ratio of resin to microspheres to this is added 45 to 50% of polytetrafluoroethylene plus 12-13% ceramic fibers, example:
100 gms of resin +35% by weight of microspheres, i.e.
65 gms resin
35 gms microspheres
40-45 gms Teflon™
b 12-13 gms ceramic fibers
The Resin and Fillers are blended uniformly for 5 minutes. Slight warming will lower viscosity for easier handling, the resin mix is then vacuum degased for 3 minutes at 28" Hg.
Appropriate amounts are screed onto the surface to provide a minimum of about 0.060 thickness coating on the test samples described below.
Parts are placed in a curing oven for 3 hours at 100 degrees C. and 1 hour at 180 degrees C. and allowed to cool to 150 degrees before removing from oven.
Surface of samples are machined to a 120 micron finish and the surface is air blasted clean. The surface is inspected at 30× to 50× to insure removal of particles from the fractured microsphere cavities and undercuts.
TENSILE TESTING
Tensile tests are performed on each of the two sample pieces per conventional ASTM tensile tests.
Minimum tensile test results should average 2000 psi with no value lower than 1750 psi.
Five samples of abradable coatings were tested for tensile strength. The samples were as shown below:
______________________________________SAMPLE NO. RESIN TO TEFLON ™______________________________________1 2 to 12 3 to 13 4 to 14 4 to 15 45 to 23______________________________________
MICROEXAMINATION
The samples were cross-sectioned and prepared for examination. All five coatings showed good adhesion to the substrate. Porosity varied from approximately 15 to 20% on Samples No. 1 and 2 to approximately 50% on Sample 5. No cracking was present in any of the samples.
COEFFICIENT OF FRICTION
The coefficient of friction for the five samples was determined as shown below:
______________________________________ KINETIC STATICSAMPLE COEFFICIENT COEFFICIENT RESIN TONO. OF FRICTION OF FRICTION TEFLON______________________________________1 .173 .360 2 TO 12 .168 .312 3 TO 13 .190 .325 4 TO 14 .203 .302 4 TO 15 .190 .472 45 TO 23______________________________________
MECHANICAL TESTS
The samples were adhesively bonded with epoxy as shown in FIGS. 1-3 and mechanically tested to determine tensile properties and location of failure. The test results are shown below:
______________________________________ TENSILE STRENGTH LOCATION OFSAMPLE NO. PSI FAILURE______________________________________1 2700 COATING2 2550 COATING3 2700 COATING4 2750 COATING5 1150 COATING______________________________________
CONCLUSION
From the preceding examination we may make the following observations:
a. No disadhesion from the substrate or cracking was present on any of the samples.
b. The amount of porosity varied from approximately 15% to 50% between the samples.
c. The tensile strengths were consistent, ranging from 2550 to 2750 PSI, except on Sample 5, where the tensile strength was 1150 PSI.
While there has been shown and described a preferred embodiment of the invention, it will be appreciated that other embodiments will be readily apparent to those skilled in the art and it is desired to encompass such obvious modifications and variations within the spirit and scope of the claims appended hereto. | A turbine engine having an interior housing and one or more annular abradable seals for the turbine blades. The abradable seal comprises a resin having fractured hollow inorganic non-metallic microspheres forming nooks, crannies and undercuts in the resin and a solid lubricant in the resin and in the nooks and crannies and undercuts formed by the fractured hollow non-metallic inorganic microspheres. | 8 |
This is a continuation of application Ser. No. 139,004, filed Dec. 29, 1987, abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a flexible exhaust duct and more particularly to a system of flexible and rigid parts of an exhaust duct and means for attaching the duct to a clothes dryer.
2. Description of the Prior Art
In clothes dryers, a source of heat sufficient to dry the wet clothes in the dryer is drawn through the dryer by a blower. After the heat has been drawn through the dryer containing the clothes, it is necessary to vent the heated and humid air. To this end, an air exhaust conduit is provided that extends from the blower housing within the cabinet of the dryer to an area outside the dryer. For example, it is known to extend the air exhaust conduit from the cabinet to a window so that the heated air is vented outdoors.
Due to the construction of the basement or other location where the consumer may locate the dryer, it may be necessary or desirable to extend the air exhaust conduit from a specific side, rear or bottom of the dryer. To this end, plugged apertures are provided in the dryer cabinet side walls, rear walls and bottom wall to permit the consumer to move the exhaust conduit to exit through the appropriate panel as required by the particular installation characteristics.
Since the distance and direction from the blower exhaust opening to each of the panel apertures is different, it is necessary to provide a means for directing the exhaust air from the blower to each of the exhaust outlets. Rigid conduit is not useful since generally it is required to have a 90° turn for the side or bottom openings but a straight flow path for the rear opening. Therefore, this would require the user to assemble or disassemble an elbow within the limited access area within the dryer cabinet. To do so would most likely require removal of one or more of the panels to provide greater access for the required manipulations of the exhaust conduit. Preferably flexible exhaust ducts would be used.
Flexible exhaust ducts are known which are comprised of rigid end pipes attached to flexible corrugated tubing such as aluminum tubing. The connections between the end pipes and the flexible tubing has been accomplished in a variety of manners including securing the two members together by wrapping the joint with an adhesive tape, securing the two members together with metallic staples extending through the two pieces or by applying an adhesive between the two pieces to secure them together. Each of these methods has serious disadvantages, particularly where the exhaust duct is used in an environment such as a clothes dryer where the exhaust will include lint particles and air at an elevated temperature.
For example, the staple method of attachment results in protruding ends of the staples extending into the exhaust air flow stream which serve as collection points for the lint particles resulting in an accumulation of lint at that location which eventually results in restriction or blockage of the conduit. In addition to reduction in efficiency of the dryer due to reduced air flow, the accumulation of lint can increase the possibility of overheating. Similar problems develop with the use of adhesives and tape to secure the members together in that if a zone of adhesive material is exposed to the air stream, lint will collect at that zone and will result in an accumulation of lint as described above. Also, such a joint may fail over time either due to improper initial application of the adhesive or breakdown of the adhesive due to the high temperature environment of a dryer exhaust duct. Also, in each of these instances an edge of either the flexible conduit or end pipes remains exposed in the air stream and also serves as a catch point for lint.
Other problems develop with multi-venting installations in that movement of the conduit from one panel opening to another causes movement at the joint between the conduit and the blower exhaust opening which may cause a leak to develop at that joint. If a leak develops there, then hot, moist, lint-ladened air will be directed into the interior of the cabinet which could result in damage to various components within the dryer cabinet including the motor and controls. Attachment of the free end of the conduit to the panel through which the end piece projects also is critical so as to prevent the end piece from falling into the interior of the cabinet.
SUMMARY OF THE INVENTION
The present invention provides a flexible exhaust ducting system in which the end pipes and flexible tubing are joined by partially inserting the tubing into the end pipes and cold rolling the tubing and end pipes together to produce a cold rolled joint in which the terminal ends of the tubing are pressed against the inside surface of the end pipes in a recessed position relative to the air flow path and, due to the contour of the end pipe at the joint, the tubing is locked in place to the end pipes. This cold rolled joint recesses the sharp edges of the bare flexible aluminum duct, removing them from the air flow path and minimizing their ability to catch lint, and provides a rigid, secure and positive means of attachment of the tubing to the end pipes.
This ducting system results in reliability in that the joint is not adversely affected by temperature or age, the tensile strength of the joint exceeds that of the bare aluminum duct and since the cold rolled joint does not impede air flow at the connections, such as that described above with respect to conventional methods of attaching flexible tubing to end pipes, the performance of the duct system is greatly enhanced.
A U-shaped bracket with slotted mounting holes is used to secure the front end pipe to the dryer cabinet. This adjustable bracket assures that the connection to the blower housing is secure and virtually leak-free. The bracket is mounted to the cabinet base instead of the rear of the blower housing. This arrangement allows movement of the flexible aluminum duct during relocation of the duct to different cabinet vent holes and prevents transmission of this movement to the blower housing. This prevents deflection of the blower housing which could cause interference with the blower wheel as well as assures the maintenance of a tight seal between the conduit and the blower housing.
The rear end pipe is secured in the cabinet opening on one side by a fork bracket. The other side clamps the cabinet metal between a tab bracket and a screw and washer combination. This arrangement holds the end pipe securely and makes switching to the other cabinet openings an easy one tool operation. From the outside of the dryer, the installer will attach the exterior exhaust tubing to exhaust the dryer air to the outside. This would complete the system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the dryer embodying the principles of the present invention.
FIG. 2 is a top sectional view of the dryer taken below the dryer drum.
FIG. 3 is a sectional view taken generally along the line III--III of FIG. 2 showing the front end pipe mounting arrangement.
FIG. 4 is a top view illustrating the connection structure at the rear end pipe.
FIG. 5 is a sectional view taken generally along the line V--V of FIG. 4.
FIG. 6 is a side elevational view of the assembled flexible tubing and end pipes.
FIG. 7 is an enlarged sectional view of the connection of the flexible tubing with the front end pipe.
FIG. 7A is an enlarged sectional view prior to connection of the flexible tubing with the front end pipe.
FIG. 8 is a an enlarged sectional view of the connection of the flexible tubing with the rear end pipe.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a dryer 10 comprising a cabinet 14 having a front panel 15 with an openable door 16 revealing an access opening 18. The cabinet 14 also has side panels 37A and 37B, a rear panel 39 and a bottom panel 41. The console 20 has presetable controls 22 thereon allows an operator to preselect a program of automatic drying and tumbling in a laundry drying process. The door 16 in the front panel 15 of the cabinet 14 permits access through the access opening 18 into the interior of a drum 24 having open ends which is rotatably mounted within the cabinet 14.
Below the drum 24 but within the cabinet 14 there is provided an electric motor 26 which rotatablY drives the drum by means of a belt 28 and also drives a blower 29. The blower 29 draws heated air into the drum 24 which is used in the drying process.
As best seen in FIG. 2, the blower 29 comprises a housing 29A having a cylindrical portion 29B forming a first duct means located in the interior of the cabinet. The heated air that has been used in the drying process is vented from the blower duct means 29B through an air exhaust duct or conduit 31 which passes through one of a plurality of exhaust openings 35, located in a side panel 37A and 37B, rear panel 39 or bottom panel 41. The air exhaust conduit 31 is a flexible and expandable tube preferably comprising a corrugated aluminum tube 32 connected to a rigid front end pipe 33 and a rigid rear end pipe 34.
The assembly of the conduit 31 is shown in greater detail in FIGS. 6-8 where it is seen that the front end pipe 33 has a generally cylindrical forward end portion 36 having a diameter sized to provide a tight slip fit over a cylindrical extension 38 of the blower duct means 29B thereby to provide a tight fit between the duct extension 38 and the front end pipe 33. The front end pipe 33 has an enlarged diameter portion 40 which is connected to the cylindrical portion 36 by a first outwardly diverging wall 42. The enlarged diameter portion 40 is connected to a cylindrical rear end 44 by a second outwardly diverging wall 46. The rear end 44 has a slightly outwardly turned lip 48. The diameter of the cylindrical end portion 44 is slightly greater than that of the forward cylindrical end portion 36.
As seen in FIG. 7A, the flexible metal tubing 32 has a forward generally cylindrical end 50 having a diameter slightly less than that of the rear cylindrical end 44 of the front end pipe 33 so that it can be slipped into the open end of the front end pipe. The forward cylindrical end 50 of the tubing and the front end pipe 33 are joined together by cold rolling the pieces together to produce a joint shown in FIG. 7 wherein the forward end 50 of the tubing is radially deformed to conform to the shape of the end pipe. This step can be done after the end pipe has been shaped with the enlarged diameter portion 40 as illustrated in FIG. 7A, or the shaping of the end pipe can be done simultaneously with the formation of the joint between the end pipe 33 and the tubing 32.
In either event, a joint such as that illustrated in FIG. 7 is achieved wherein the tubing 32 is locked to the end pipe due to the contours formed, such that the tubing 32 is prevented from moving axially relative to the end pipe 33. This cold rolling process forms such a tight joint that relative rotational movement of the tubing and end pipe is also prevented. A terminal front edge 52 of the tubing 32 ends up in a protected area on the inside of outwardly expanding wall 42 so that the sharp edge is positioned out of the main air stream flowing through the conduit thereby minimizing the possibility that lint will catch and collect at that edge.
The end pipe 34 has a forward end configuration substantially identical to the configuration of the rear end of the front end pipe 33 in that it has an enlarged diameter portion 60 connected to a cylindrical rear end 62 by a first outwardly diverging wall 64 and is connected to a generally cylindrical forward end 66 by a second outwardly diverging wall 68 such that an identical connection is provided by radially deforming the tubing 32 into close engagement with the rear end pipe 34 as is described above.
The benefits of this type of a joint are that the joint is highly reliable in that it is not adversely affected by temperature or age and the cold rolled joint does not impede air flow at the connections thus providing greatly improved performance of the duct over conventional methods of utilizing flexible metal ducts and connecting them to the rigid end pipes. Further, Applicants have tested this joint construction relative to its tensile strength and have determined that the tensile strength of the joint exceeds that of the bare aluminum duct. Therefore, failure of the joint during use is highly unlikely.
As best seen in FIGS. 2-5, the exhaust conduit 31 is secured in place by attaching the conduit to the cabinet 14 of the dryer by providing a U-shaped bracket 70 to secure the front end pipe 33 to the bottom panel 41 of the cabinet and by providing two diametrically opposed brackets 74, 76 at the rear end pipe 34 which clamp the rear end pipe to a selected one of the rear panel 39, right side panel 37A, left side panel 37B or bottom panel 41 as is required by the particular installation configuration.
The U-shaped bracket 70 is provided with a pair of outwardly extending end tabs 80, 82 each having a slotted mounting hole 84, 86 therethrough for receiving a threaded fastener 88. Attaching the adjustable bracket 70 to the floor panel 41 of the dryer cabinet assures that the connection from the exhaust conduit 31 to the blower housing 29A is secure and virtually leak free. Movement of the flexible duct 31 when relocating the rear end pipe 34 to an opening in a different panel of the dryer cabinet will not result in a transmission of this movement to the blower housing due to the connection to the floor panel thus assuring a continued leak-free connection between the conduit 31 and the blower housing 29A.
As described above, the rear end pipe 34 is secured to a panel of the dryer cabinet by means of two brackets 74, 76, the first bracket 74 being a fork bracket having one tab portion 88 separated from a second tab portion 90 by a recess 92. The two tab portions 88, 90 are offset from each other so as to occupy different planes such that the first tab portion 88 will overlie an interior surface 91 of the particular panel through which the end pipe 34 is projecting and the second tab 90 will overlie an exterior surface 93 of that panel. An edge as of the opening is received in the recess 92 so that the fork bracket will in effect be hinged to the panel. An aperture 94 is provided in the second tab for receiving a threaded fastener 96. Threaded fastener 96 is used to secure the fork bracket 74 to the panel when venting through the bottom panel 41 but is unnecessary for other exhaust openings 35. The fork bracket 74 is attached to the end pipe 34 by appropriate fastening means 98 such as a rivet.
The second bracket 96 is generally L-shaped which is designed to overlie the interior surface 91 of the panel through which the end pipe 34 is extending and the bracket includes an aperture 100 for receiving a threaded fastener 102, carrying a washer 103, which extends through the panel to clamp the bracket 76 against the panel. The bracket 76 is secured to the rear end pipe 34 by an appropriate fastening means 104 such as a rivet.
The conduit 31 can be easily repositioned by removing the two fasteners 96, 102, and the washer 103 pushing the end pipe 34 of the conduit into the interior of the dryer cabinet, redirecting it toward an opening in a different panel wall, rehinging the fork bracket onto the opening in the panel wall and refastening the two threaded fasteners 96 and 102 and the washer 103 to again secure the end pipe 34 to the cabinet panel.
Thus, it is seen that the present invention provides a flexible exhaust ducting system for a dryer wherein the dryer has a cabinet with a bottom panel and four side panels, at least two of the side panels having an opening means therethrough for passage of an exhaust duct, and the dryer also including a blower housing with an exhaust opening within the cabinet. The ducting system comprises a flexible and expandable tubing with two open ends and two rigid end pipes, one secured to each end of the tubing. One of the end pipes is sized to join to the blower housing exhaust opening and the other of the end pipes is sized to extend through one of the panel openings. The system also includes bracket means at each end pipe securing the end pipes to at least one of the panels. The end pipes and flexible tubing are joined by deforming the tubing into engagement with the end pipes, preferably by radially deforming the tubing outwardly into engagement with at least a portion of a varying diameter contour of the end pipes to securely lock the tubing and end pipes together. In this manner, a trouble free joint is provided between the tubing and end pipes which does not require any additional fastening devices and which is not affected by heat or age. By securing the conduit to the panels themselves rather than to any component such as the blower housing, movement between the end pipe and blower housing is prevented thereby assuring a continued tight seal between those two members.
As is apparent from the foregoing specification, the invention is susceptible of being embodied with various alterations and modifications which may differ particularly from those that have been described in the preceeding specification and description. It should be understood that we wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of our contribution to the art. | A flexible exhaust ducting system is provided for a dryer wherein the dryer has more than one opening through its cabinet panels for an exhaust outlet to accommodate differing installation configurations. The ducting system includes a flexible metal tubing which is radially deformed into contact with rigid metallic end pipes to provide a trouble free joint. The end pipes are secured to the cabinet bottom panel at an end connected to the blower and to the panel through which the conduit exits the cabinet at the other end to prevent accidental dislodging of the conduit. | 3 |
This application is a continuation of patent application Ser. No. 60/276,856 filed on Mar. 19, 2001.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to delayed coking processes and coke drums in particular. More particularly the invention related to a system for accurately determining the froth or foam level in a coke drum on a delayed coking unit.
2. Related Information
Delayed coking processes are used in petroleum refineries to convert residuum, vacuum tower bottoms or other asphaltic process streams—normally referred to as charge on a delayed coker—into more valuable refinery products such as gasoline, diesel and gas oils. Process equipment normally associated with a delayed coker are a main fractionating tower, furnaces, coke drums, fractionation equipment, pumps, a compressor, various heat exchangers, etc. One of the products produced on a delayed coker is petroleum coke which is formed in the coke drums.
In the delayed coking processes, the residuum or other asphaltic material is circulated through a furnace for heating to coking temperature and then delivered to the coke drum where a coke product as well as the more useful products form from the thermal cracking of the heated heavy hydrocarbons. The overhead of the coke drum is quenched and circulated to a combination or fractionating tower for separation of the overhead into gas, gas oil, fuel oil, naphtha and the like. When the coke drum is filled with coke, a mechanical process of removing the coke from the coke drum is begun. Generally during the process of removing the coke from the coke drum, the circulation of the heated heavy hydrocarbon is switched to a second coke drum which fills with coke as the first coke drum is being mechanically emptied. The time between switching coke drums is the coking cycle. Most delayed coking units are operated to maximize charge rate. The variable that generally controls or dictates the charge rate is the level in the coke drum. In the vernacular of the industry that level is referred to as the foam level.
Once the foam level has reached what is considered an optimum level the charge from the furnace is switched to a second drum. The filled drum is then steam stripped for removal of residual light hydrocarbons and then cooled with water. In the process of stripping, cooling, etc., the material in the coke drum solidifies into petroleum coke which is removed mechanically.
The coke drum is designed to contain the coke and any other phenomena associated with the formation of petroleum coke. An inherent part of that process is the formation of foam in the coke drum. Downstream equipment used to recover the higher valued products from the coking process are not designed to handle the foam hence the need to assure its containment within the coke drum.
Many theories abound as to the phenomena of what is taking place in an operating delayed coker coke drum. The common theory is that the coke forms from the bottom of the drum up as the heated charge passes from the furnace into the coke drum. This theory says that “rat holes” form in the coke which allows the subsequent material to pass up through the drum.
The inventor herein has noted that the material left in the coke drum which has not been properly cooled oozes out of a coke drum after the head is removed which contradicts the theory that solid coke has formed. Also large amounts of steam, which is a vapor at the process conditions (temperature and pressure) utilized in the coking process, are injected with the charge residuum at the furnaces. If the hot residuum formed solid coke with “rat holes” as soon as it entered the drum as previously describe, an inordinate amount of back pressure for the incoming charge would develop. Further, by design 45+% of the residuum vaporizes in the coking furnaces. Ultimately as much as 70% by weight of the charge is thermally cracked to hydrocarbon vapors in the coke drum which has to flow up through the material in the coke drum into downstream recovery equipment. This vapor flow would be impeded and aggravate the back-pressure problem if solid coke was forming from the bottom of the coke drum upward as the drum is fed.
SUMMARY OF THE INVENTION
The invention is based upon the hereto before undiscovered phenomenon that the material in the coke drum is a boiling, highly viscous and fluid mixture of hydrocarbon material in which thermal cracking is taking place. The thermal cracking, the vaporization that has occurred in the furnaces, and the steam injected at the furnaces result in the evolution of large bubbles of hydrocarbon gases and steam. The bubbles at the bottom of the drum are smaller and grow into larger bubbles as they flow upward through the boiling, cracking mass of hydrocarbon material being fed into the drum and combine with other cracked hydrocarbon vapors and steam. The entire mass of material in the drum is being continuously fed and is boiling much as viscous material boils on a kitchen stove. The boiling mass of material in the coke drum has a hydrocarbon vapor and steam-foam or a hydrocarbon vapor-bubble interface where the large bubbles are bursting. This interface moves up the drum as the drum is filled from the bottom. The material left in the drum after the bubbles burst is the material that forms the petroleum coke when cooled. If this material is carried out the top of the coke drum into downstream equipment serious fouling and upsets occur. Hence, after this hydrocarbon vapor-foam interface moves up the drum, it is extremely important to accurately monitor that interface to assure the foam does not go out the top of the drum with the hydrocarbon vapors.
The hydrocarbon vapors in a coke drum have a lower density immediately after switching to a new drum. After running into the drum for several hours the hydrocarbon vapors tend to get more dense for a few hours. The hydrocarbon vapors get even more dense near the foam front and the foam is very noticeably denser than the hydrocarbon vapors. Since the material in the coke drum is a boiling mass with larger bubbles at the top and smaller bubbles at the bottom, at steady state conditions the material in the drum has a density change that is fairly linear being less dense at the top and more dense at the bottom. At non-steady state conditions, though, the density at any given point in the drum changes.
The density of the foam or boiling hydrocarbon in the coke drum at any given elevation in the drum from the top of the hydrocarbon-foam interface down to the bottom of the drum and at any given time changes as a function of several factors. Some of these factors include the type of feed being fed to the coke drum, the velocity of the hydrocarbon vapor flow through the boiling mass as a result of the feed rate to the coke drum being changed (something not abnormal on a delayed coking unit), injection of an anti foam material into the coke drum which helps to collapse the bubbles at the hydrocarbon vapor and the steam-foam interface by reducing the surface tension of the bubbles, sudden changes of pressure inside the coke drum from switching the coke drums and other normal functions on a delayed coking unit, changes in temperature inside the coke drum, etc. This phenomenon had not been previously recognized by the industry, but it can be demonstrated by and likened to boiling viscous material in a pot on a kitchen stove.
The discovery and use of the heretofore unknown phenomenon enabled the inventor to determine the appropriate length, configuration and mounting of nuclear detectors and use, calibrate and display the output of those detectors in a distributive control system (D.C.S.) or computer to precisely track and monitor this phenomenon and which is the invention.
The system may most briefly be said to comprise:
(a) a plurality of linear radiation detectors mounted length wise along the height of the coke drum;
(b) a radiation source or sources mounted on the coke drum opposite said radiation detectors;
(c) each of said radiation detectors initially calibrated to read one hundred percent level when no radiation is detected.
The method of detecting the level comprises:
(a) placing a plurality of radiation detectors along the height of said drum;
(b) placing a radiation source on said drum opposite said radiation detectors;
(c) calibrating each of said radiation detectors to read zero percent of level at the radiation count transmitted when only hydrocarbon vapors are present in the drum
(d) Initially calibrating each of said radiation detectors to read one hundred percent when no radiation is detected
(e) correlating the detected radiation as a percentage of the height of each radiation detector as radiation is blocked by the foam level rising in the coke drum;
(f) transmitting the radiation count of each radiation detector to a distributive control system or computer for display;
(g) multiplying the percentage reading for each detector by the fraction of height each detector is in relation to the total height of all the detectors to give a product; and
(h) summing all of the resulting products to give a foam level.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic in plan view of a coke drum showing the location of the radiation source and detector tubes.
FIG. 2 is a schematic of the method of calculation of the foam level.
FIG. 3 is a schematic in plan view showing more detail of the mounting of the detector tubes on the coke drum.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Because of economic considerations it is important to safely utilize as much of the drum capacity as possible. In addition, the industry practice is to inject a material into a coke drum in an effort to minimize the height of the foam as previously described. The anti foam agent is typically a silicon based compound or chemical. The silicon is deleterious to downstream processing units and therefore its usage is generally limited to minimize that impact. Typically anti foam agents are injected when the foam front nears the top of the coke drum although some refiners inject the anti foam agent on a continuous basis. The level system of the present invention allows optimizing the amount of anti foam agent used to control the foam level in the drum.
Due to the importance of not allowing foam to flow out the top of the coke drum it is extremely important to accurately and continuously monitor the foam level as it approaches the top of the drum to assure that does not happen. Accurately and continuously monitoring the foam level has heretofore not been possible because the phenomenon of the boiling hydrocarbons which is happening in the coke drum was not understood. The present invention, however, provides a system which continuously monitors with extreme accuracy the foam level in the coke drum to within +/−one foot. Accuracy is only limited by changing dynamics at the hydrocarbon vapor-foam interface due to the numbers and size of the large bursting bubbles.
Based upon the “rat hole” theory the prior art drum level detection systems typically use back scatter radioactive devices which are normally referred to as point detectors, meaning each detector provides an indication at a precise point on a coke drum. The system works on the basis of the concentration of hydrogen ions or molecules in the material in the coke drum. Usually a point detector level system consists of four point detectors mounted at different elevations on the coke drum. Each detector has a radioactive source that emits radiation. The particular radiation emitted is absorbed in proportion to the concentration of hydrogen ions or molecules present. Each detector is capable of monitoring an area of the coke drum that is approximately a thirty six inch diameter circle. The measure of the amount of radiation absorbed is used to indicate more or less dense hydrogen rich material at that area of the coke drum. Since the material in the coke drum is hydrocarbon based material hydrogen ions or molecules are present and the concentration of the hydrogen ions or molecules are indicative of the density of the hydrocarbons. Since coke drums range from sixty to one hundred twenty plus feet in height and eighteen to thirty plus feet in diameter, four detectors such as these point detectors cannot monitor a long vertical distance of the drum to provide continuous measurement of the hydrocarbon vapor-foam interface. Consequently the drum cannot safely be utilized to the maximum.
The other prior art level system in use over the years consists of one long (16 to 20+ feet) detector (an ion chambers or other long linear detection device) mounted on the side of the coke drum which measures the amount of radiation emitted from a radioactive source which is mounted on the opposite side of the drum.
The output of a linear detector is the average radiation count over the entire length of the detector. Consequently the output of the detector can indicate the same radiation with a less dense material between the radioactive source and the entire length of the detector as with a more dense material between the source and the lower one fourth of the detector. Hence with a changing density in the coke drum one detector cannot provide an accurate indication of the foam level by the time the foam has reached the top of the detector tube.
The industry has not applied or used the heretofore undiscovered phenomenon noted by the inventor to develop a level system that is accurate. The assumption has been that the density of the foam in the coke drum is a constant and that the long detector accurately reflects the foam level once calibrated when it fact it does not. Industry has never configured the various components of a radioactive system to provide an accurate and continuous portrayal of the hydrocarbon vapor-foam interface phenomenon. Too, the prior art systems cannot be calibrated to provide a continuous indication of the hydrocarbon-foam interface that is accurate for the reasons indicated above.
Because of the size of the foam bubbles in a coke drum and varying density of the foam in a coke drum the invention requires a level system having multiple radioactivity detectors such as ionization tubes, scintillation detectors or other types of linear detectors of varying but relatively short lengths mounted vertically along the side of the coke drum to achieve the resolution necessary to provide accuracy of measurement. A long detector configured with switches or other devices to make it perform as several short detector tubes can also be used.
Each detector can be from one to two feet in length up to six feet or so in length depending on the total length of the level system and the diameter of the coke drum. The resolution needed to achieve the desired accuracy determines the length of each individual detector and requires that the level system is always to be comprised of multiple relatively short detectors mounted vertically along the side of the drum. The number of detector tubes used is determined by the vertical distance of the coke drum to be monitored. The detector tubes may be mounted end to end or be separated by some nominal distance determined by the drum diameter. Individual detectors mounted end to end but separated by a nominal distance provides greater accuracy for larger diameter drums. The strength and number of radioactive sources to be used with each level system is determined by the manufacturer of the radioactive source and the detectors. Suitable radioactive sources are Model No. SH-F2-01K-A30-M3-SOO-PO Radioactive Source Holder with a 1000 Mci Cesium 132 Source manufactured by OhmartVega Corporation of Cincinnati, Ohio. Suitable scintillation detectors include Model LSTH-060-HO-MO-SOO-PO also manufactured by OhmartVega Corporation of Cincinnati, Ohio.
The detectors are initially calibrated such that when the coke drum has hydrocarbon vapors in it, e.g., after the drum has been charged for three or four hours, the radiation count at that time will represent a zero foam level at the detectors. Whether it is done at that time or at some other time, the window on the radioactive source holder is closed such that no radiation is detected by the detector. Each individual detector is then calibrated such that this reading represent 100% for each detector. If there are five equal length detector tubes comprising the entire detector level system each tube at 100% will represent one fifth or 20% of the entire foam level.
After the drum is charged the level detectors are recalibrated to provide the extreme accuracy required to monitor the foam level. Foam rises in the coke drum as the drum is charged and passes the lowest detector which causes the radiation count transmitted from the detector to begin to fall. When the foam passes the top of a lower detector the radiation of the next highest detector will begin to fall. The lower detector will then be recalibrated to indicate 100 percent level at the radiation count it was reading at the time the radiation count on the next higher detector begins to fall. The remaining detectors are recalibrated accordingly. The radiation count used to reset the 100 percent level of all the lower detectors is linear and the radiation count determined from that linearity is used to recalibrate the top detector to indicate a 100 percent level of that detector.
Referring now to FIG. 1 a schematic of the coke drum 10 with the radiation sources 41 and 42 in place is shown. The coke drum 10 is shown to have an inlet 20 at the bottom where the heated residuum or hydrocarbon is fed. Vapors formed as a result of the thermal cracking are removed via an overhead line 30 . Flanged header 40 provides access after the coking cycle is complete. Opposite the radiation sources are the detectors 51 – 55 each having active lengths 51 A- 55 A within the tubes but generally not extending the entire length of the tube. The signals representing the radiation count from the detectors are carried to the control house and computer via electrical signal lines 61 – 65 .
Referring now to FIG. 3 more detail of the mounting of the detector tubes 51 – 55 is shown. A central mounting bracket 70 is secured to the outside of the coke drum 10 . Detector tube 51 with sensing element 51 A is mounted to the central bracket 70 by mounting brackets 71 and 72 . Detector tube 52 with sensing element 52 A is mounted to the central bracket 70 by mounting brackets 73 and 74 . Detector tube 53 with sensing element 53 A is mounted to the central bracket 70 by mounting brackets 75 and 76 . Detector tube 54 with sensing element 54 A is mounted to the central bracket 70 by mounting brackets 77 and 78 . Lastly detector tube 55 with sensing element 55 A is mounted to the central bracket 70 by mounting brackets 79 and 80 . The detector tubes 51 – 55 are mounted substantially end to end, however these can be mounted such that there is some space separating the sensing elements 51 A– 55 A.
When foam rises in the coke drum and begins to block or absorb the radiation such that the detector tube is sensing less than the zero setting, the indicated output of the detector for the tube will begin to show a foam level. As the foam level continues rising, the detector tube transmits less and less radiation and the indicated level of the foam rises toward 100% of that detector which accounts for a percentage of the total level. FIG. 2 indicates the calculation as the signals come into the calculator via electrical signal transmitters 16 – 65 . The raw count is then multiplied by the percentage of the whole that each tube is accountable and then summed to get the total level.
Although each tube has been calibrated to show 100% level when it detects no radiation, the foam at this time may not be dense enough to completely block the radiation and the detector may still be transmitting a radiation count. With the foam level completely covering a detector but yet the detector still transmitting a radiation count, the radiation count of the detector above may begin to fall indicating the foam has actually reached the next level. This resolution is part of the reason for the placement of a plurality of detectors along the length of the drum with some nominal distance between the active sensing area of each detector. The nominal distance may be a few inches to a foot depending upon the desired accuracy.
The number of detector tubes will depend upon the height of the drum and the desired level of accuracy and the vertical height of the drum that is to be monitored. | A foam level in a delayed coking drum is detected by utilizing the varying density of the boiling mass in the coke drum which has larger bubbles and is less dense at the top and smaller bubbles and a higher density at the bottom. A plurality of radiation detectors are disposed on the drum and calibrated such that zero radiation is equivalent to 100 percent level. The percentage reading for each detector is multiplied by the fraction of height each detector is in relation to the total height of all the detectors to give a product and the products summed to give a level. | 8 |
This application is a continuation-in-part of copending application Ser. No. 12/445,850, filed Apr. 16, 2009, which was the U.S. national stage of international application PCT/AU2007/001580, filed Oct. 17, 2007.
FIELD OF THE INVENTION
This invention relates generally to down-hole hammer drills and more particularly to a down-hole compressed fluid driven hammer drill as described below.
BACKGROUND OF THE INVENTION
Down-hole hammers generally comprise a drill bit as the lowermost component in the hammer assembly. The drill bit has a major diameter portion referred to as the bit head, and determines the diameter of the hole drilled. The bit head is traditionally integral with an upper, splined bit shank, which is slidably engaged and retained within a driver chuck. The driver chuck has an internal spline for engagement with the drill bit shank spline, and an outer threaded portion to engage a down-hole hammer barrel.
The bit shank splined section, when engaged within the driver chuck, is mechanically engaged rotationally, but is free to slide axially. To limit the extent of axial travel, and to prevent the drill bit from sliding out of engagement altogether, the drill bit shank has a section of reduced diameter above the spline, for a distance equivalent to the desired travel length of the spline plus the thickness of a retaining mechanism. This retaining mechanism is a bit retainer ring, made of two semi-circular sections with inner and outer diameters that are placed from each side around the reduced diameter of the bit shank thereby forming a near complete ring. The final section above the reduced diameter is the bearing land, which varies in form but is always of substantially larger diameter than the reduced diameter, so as to limit the axial travel as the bearing land comes to rest on the bit retainer ring.
In use, the driver chuck is lowered onto the drill bit shank, with the mating splines engaged. The two halves of the bit retainer ring are fit to the reduced diameter portion of the bit shank and rest atop the driver chuck. The drill bit, chuck and retainer ring sub assembly are threaded into the down-hole hammer casing/barrel. The bit retainer ring, now encased circumferentially within the down-hole hammer barrel, driver chuck below, and drill bit guide bush above, permits limited axial travel of the splined engagement.
It would be desirable to reduce the manufacturing cost of drill bits. The most effective way of doing so is to redesign the product so as to reduce its mass and length, while maintaining a robust and practical product.
EP1757769A1 discloses splines machined into the casing, a chuck fitted from above and a drill bit screwed into the chuck from below, providing for a shorter and more cost effective drill bit.
WO2008044458A2 discloses a type of drill bit for down-hole hammer use that is designed to be short and efficient to manufacture and use.
WO2009124051A2 discloses two embodiments of drill bits for down-hole hammer use that are designed to be short and efficient to manufacture and use.
WO2007077547A1 discloses a drill bit with a shorter shank than conventional types, also having threaded attachment.
My prior application, identified in the first paragraph above, disclosed embodiments of the invention illustrated in FIGS. 1-6 of the drawings. The description and claims below describe new embodiments, illustrated in FIGS. 7-9 .
SUMMARY OF THE INVENTION
In its broadest sense, the present invention includes: a hammer casing; a free piston motor in the casing; a drill bit having a separable bit shank extending from a bit head to an anvil end, the bit shank being keyed for reciprocating and driven rotation in the bore of a casing or chuck; and a number of keys or pins rotationally connecting the bit shank to the casing or chuck.
The check valve tube may comprise a perforate cylinder or the like functioning as a debris screen. Alternatively, the upper poppet check valve may be independent of the lower check valve in that the check valve tube and poppet valve may be associated with a spring and form a poppet valve assembly locatable at the upper end of the porting tube, seating onto said check valve tube and located directly adjacent the pressure supply ports of said porting tube, spring actuated from above by a connecting rod or from below by a spring supported by choke plug.
The pins may be considered sacrificial drive engagement pins, or keys, and may be of any suitable cross sectional shape as is practical and of any number as is practical. For example, the pins may be round section drive pins or may be of a section more like a keyway key.
In my prior application, I described the use of alternating long and short pins, whereas in the new embodiment of FIGS. 7-9 , the pins are all the same length and function, the drill bit's head and shank are now two separate parts; this enables the shank/anvil to fit into the casing in the new manner described below, and allows the pins to be of uniform length and function. This improvement eliminates the need for a driver, as does the embodiment of FIG. 6 , and provides a mechanically detachable drill head.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be further described with reference to a embodiments of the invention as illustrated in the accompanying drawings and wherein:
FIG. 1 shows an isometric exploded view of apparatus in accordance with the present invention;
FIG. 2A shows an axial section of the down-hole hammer assembly of FIG. 1 ;
FIG. 3A is the hammer assembly of FIG. 1 lifted away from contact with the rock;
FIG. 3B is a view of the top adapter sub through section 3 B of FIG. 3A .
FIG. 4A is a sectional elevation of the barrel porting construction of the down-hole hammer assembly of FIG. 1 ;
FIG. 4B is a view of the hollow porting tube of the apparatus of FIG. 1 ;
FIG. 4C is an elevation of the barrel and driver chuck exterior of the apparatus of FIG. 1 ;
FIG. 4D is a sectional view indicating the polygonal outer surface of the barrel and driver chuck exterior of the apparatus of FIG. 1 ;
FIG. 5 is a sectional elevation of an alternative embodiment of the present invention;
FIG. 6 is a sectional view of another embodiment in which the upper poppet is independent of the lower check valve; and
FIGS. 7 and 8 are sectional views of another alternative embodiment of the invention; and
FIG. 9 is an exploded perspective view thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the hammer of FIGS. 1 to 5 , a driver chuck 1 fits over a drill bit shank 2 and has a running fit, free to rotate. Longitudinal grooves 3 are machined on the inside of the driver chuck and on the outside of the drill bit shank The driver chuck is rotated on the drill bit shank until the grooves align. Shorter pins 4 are inserted into the visible holes formed by the alignment of the drill bit grooves and driver chuck grooves 3 , the chuck is indexed until the next alignment of the grooves, and the longer pins 5 are then inserted.
At this point the driver chuck and drill bit are engaged rotationally, and with the shorter pins 4 now no longer visible but engaged internally, extending axially and spaced circumferentially, the bit may freely slide a desired distance due to the internal engagement of the shorter pins. The shorter pins, which determine the allowable sliding movement, may be formed integral with either the drill bit or driver chuck. The longer pins, or keys, provide the majority of rotational drive engagement.
The embodiment of FIG. 6 is functionally identical to that of FIG. 5 , but for the elimination of the driver chuck, whose function has been integrated into the casing by means of simply duplicating the grooves 3 into the lower casing. The replaceable pins/keys as a drive and linear retention mechanism makes this synergy possible.
In operation, as shown in FIG. 2A , compressed air enters hollow port tube 6 through a central bore of top adapter sub 13 , and forces open pressure port check valve 11 against a spring 8 supported by choke plug 10 , simultaneously opening exhaust check valve 7 via connecting rod 9 . The compressed air passes through pressure port 12 , through conduit 12 a , aligning with feed port 12 b to pressurize porting channel 19 , to feed delivery ports 21 and 22 . Lower chamber 23 is energized by delivery port 22 to raise the piston 18 . As the piston rises, lower chamber 23 dumps to atmosphere via exhaust port 25 , delivery ports 21 and 22 begin to energize the piston compression chamber 14 via transfer ports 20 , the piston is forced down to impact the drill bit anvil, dumping the piston compression chamber to atmosphere when exhaust port 26 is exposed, and the cycle repeats continually while sufficient compressed fluid is supplied, or until the cycle is interrupted.
In FIG. 3A , the hammer has been lifted away from contact with rock, so the drill bit 2 is free to fall the distance permitted by the internally engaged shorter pins 4 shown in FIG. 1 , located within axial grooves 3 , followed by the reduced diameter striking end of piston 18 entering the upper portion of driver chuck 1 vacated by the drill bit 2 , thereby interrupting the percussive cycle as delivery port 21 becomes open to exhaust port 26 and dumps to atmosphere through exhaust check valve 7 until the cycle is reactivated. Note the hollow porting tube 6 remains in cooperation with the drill bit bore at all times.
The lower check valve arrangement is made possible by the hollow porting tube 6 extending from its upper support in the central bore of top adapter sub 13 into the central bore of drill bit 2 , and may be utilized as either an upper pressure check valve 11 or lower check valve 7 , or both in unison via connecting rod 9 . The co-operation of the porting tube within the drill fortifies alignment of the porting tube and permits an advantageous location of an exhaust check valve. The lower exhaust check valve positively and instantly prevents debris contamination at the first possible point of entry. This design is therefore considerably more resistant to entry of potentially damaging debris than prior down-hole hammers.
Additionally, the porting tube 6 controls the piston return chamber 23 volume, thereby eliminating requirement of a component known as a foot valve or exhaust tube, as described in prior art such as that described above.
In the present invention, cooperation of the hollow porting tube and drill bit is made practicable due to the driver chuck and drill bit combination design, in that the drill bit shank 2 is well supported in alignment within the driver chuck 1 , and has a substantial wall thickness and a bore able to accommodate a porting tube of sufficient cross-sectional area for the required airflow, the drill bit bore fashioned to provide sufficient cross-sectional area for passage of exhaust fluid through the check valve 7 .
A piston compression chamber 14 is formed integrally within the top adapter sub 13 . FIG. 2 shows a means for quickly and simply altering the piston compression chamber 14 volume. Within piston compression chamber 14 as part of the top adapter sub 13 are formed a series of axial holes 16 a . Any practical number of inserts 16 are inserted into the holes, thereby incrementally altering the volume capacity of said chamber, subsequently altering compressed fluid consumption and maximizing efficiency of the drill for any suitable compressor delivery output. The inserts are retained in the holes by known means, such as a circlip into groove 15
FIG. 4A shows the barrel porting. Ports 12 b , 21 , and 22 are radially through-drilled into the barrel 17 . Channel 19 is milled longitudinally at a depth and length suitable to encompass the drilled ports. Cap 24 is fixed in known manner to cover and seal the ports from the outside. Thus, ports 12 b , 21 and 22 are interconnected by a passage 19 formed between inner and outer surfaces of barrel 17 .
Internal transfer ports 20 are fly-cut into the barrel bore in a known manner. The effect on torsional rigidity is minimal and acceptable because only about six percent of the barrel circumference is affected per channel since the porting channel 19 need have only a cross sectional area equal to any one of the supply or delivery ports, and much of the removed metal is restored as a cover cap 24 . Furthermore, it is not necessary to fashion a cover cap flush fitting with the barrel outside diameter; however, it would be entirely acceptable to do so if the cover cap were to protrude the barrel outside diameter up to but not exceeding the diameter of the drill bit.
With this design, I have found there to be ample material thickness to accommodate a fluid conduit 19 in the manner described. This is advantageous in that material input is kept at a minimum since manufacturing of an inner cylinder is negated, as are the problematic methods of retaining the inner cylinder.
The present invention described thus far is of non-ported piston type design. While the general flow characteristics of this type of porting are known and not part of this patent application, it has a bearing on how some of the components are designed. Another embodiment of the invention, shown in FIG. 5 , maintains all of the essential features of the first embodiment, with some features altered according the porting arrangement of a ported piston. A further embodiment, illustrated in FIG. 6 , has the feature of independently actuated check valves and the elimination of a chuck by incorporating the function of the chuck into the casing. Yet another embodiment of the invention, shown in FIGS. 7-9 , maintains all of the essential features of the previous embodiment, with some feature altered according to the arrangement of a symmetrical piston incorporating a bush for guidance, timing and sealing, and a two-piece drill bit.
The embodiment of FIGS. 7-9 is substantially similar in construction and operation to the embodiments of FIGS. 1-6 , and like reference numbers denote like components.
Compressed air enters porting tube 6 and directly engages the hammer via pressure supply port 12 to begin operation. In turn, the check valve 7 is forced open by exhaust fluid against its spring 8 via connecting rod 9 . The spring is supported by choke plug 10 . The check valve arrangement may also be a sliding piston 11 atop the spring which is forced down against the spring by incoming compressed fluid, thus exposing the pressure supply port 12 . The check valve arrangement is thus mounted internally within the hollow porting tube, and may be either or both of the aforementioned arrangements in unison. See FIG. 4B .
With reference particularly to FIGS. 5-7 , a series of retainer circlip grooves 15 are formed within the piston compression chamber 14 as part of the top adapter sub 13 . An insert or inserts is placed in the piston compression chamber. The inserts are retained by a circlip (not shown) in an appropriate one of the grooves 15 , thereby altering the volume capacity of said chamber, subsequently altering compressed fluid consumption and maximizing efficiency of the present invention for any suitable compressor delivery output.
The piston 18 is ported from its upper and lower extremities via porting conduits 21 a and 22 a , such porting conduits cooperating with porting apertures in hollow porting tube 6 to effect reciprocal motion, and may be fashioned to slidably co-operate at the top of its stroke with the bore of said piston compression chamber at 14 a in FIG. 5 . A long standing problem associated with the use of known down-hole hammers is the difficulty of disassembly, due to the great torsional forces and vibration which cause the threads to become very tight and therefore difficult to undo. Hence there is a need for specialty equipment to grip and apply high force to disassemble the down-hole hammer for servicing, and often there is the persistent problem of the gripping tool or mechanism to slip, or fail to grip, on the hard outer cylindrical surface of a known down-hole hammer assembly.
In the present invention, for reasons of safety and ease of handling, are provided longitudinal flats on the outer surfaces of the barrel and driver chuck (see FIGS. 4C and 4D ), typically twelve in number. Such a peripheral shape creates no notable restriction to the passing by of exhaust air laden with crushed rock when drilling, but provides additional assurance of positive non-slip attachment of appropriate servicing tools, such as in Publication No. WO 2006015454.
The further embodiment of FIGS. 7-9 involves the integral rotation and retention means as displayed in FIG. 6 : the drive chuck is rendered obsolete by the longitudinal drive pin grooves/keyways being machined directly into the lower portion of the casing.
The further embodiment differs from that of FIG. 6 in that the drill bit head 2 b is made as a detachable component. The shank portion 2 a of the drill bit has an external helical thread 27 . While prior drills have had screw-on heads, the way in which the shank/anvil 2 a is located and supported and driven within the casing is new, and is explained in detail below.
The pin drive and linear retention mechanism design permits the loading of the shank/anvil 2 a from either end of the casing but preferably from the lower end, as would be generally convenient in field use. In that case, the drive/stroke limiting pins 5 a are inserted into the corresponding grooves within the casing, the shank/anvil 2 a then pulled downward to engage the pins, and thus the shank/anvil is engaged rotationally with the casing via the pins but may not be pulled out of the casing longitudinally due to the engagement of the pin ends in the lower end of the casing grooves and the upper end of the shank/anvil grooves.
The drive/stroke limiting pins 5 a of the embodiment of FIGS. 7-9 are sacrificial and replaceable, and are all the same length, thus simplifying assembly.
With the shank/anvil in place with the pins, the drill head may then be threadably attached to said shank/anvil, thus the assembly becomes complete.
The reader and those skilled in the art should be aware that in almost all cases, a worn drill bit of the down-hole hammer type is discarded because the drill bit head is worn to below serviceable diameter, while the shank/anvil portion is generally in good serviceable condition but must be discarded regardless, thus the advantages of the present chuckless, casing mounted, shank/anvil embodiment are evident:
1) A drill shank/anvil will outlast a drill bit head by approximately 5:1; therefore, material usage and waste disposal are reduced when only the drill head portion must be replaced. 2) There is no requirement to manufacture, maintain, or replace a driver chuck at all, it is obsolete, yet more synergy and economic efficiency. To replace a worn drill head becomes a simple matter of unscrewing the old and screwing on the new (or reclaimed) drill head, while the shank/anvil remains engaged within the casing, effectively “re-using” the shank/anvil that would otherwise have been discarded if the drill bit were a singular unitary item comprising drill head and drill shank/anvil. From the manufacturing perspective, one can make a drill head with about 50 percent of the drill bit material required for the embodiments of FIGS. 2 , 5 and 6 . 3) The shank/anvil may be threadably attached to the drill bit head, and as such the threads may be formed as parallel or tapered, male or female in either direction. Other means of mechanical engagement are possible and would be apparent to one skilled in the art.
Another feature of the embodiment of FIGS. 7-9 is that of a symmetrical piston 18 , so that if the striking surface is damaged, the piston is can be reversed end for end, thus effectively extending the service life instead of replacing a major component. This feature is made possible within this design by means of an inserted sealing/guidance/port timing bush 23 fitted to only the lower end bore of the piston. If the piston 18 is to be reversed then the bush must remain at the lower end, and the upper end remains open. Both ends of the piston bore are oversize relative to the port tube 6 on which the piston slides, the strike end being bushed for sealing and timing of the return stroke working chamber and the upper end permitting fluid flow in the drop-open condition (hammer cycle interrupted inducing full-flow bypass for flushing, indicated by arrows in FIG. 8 ).
A symmetrical, or double ended piston costs no more to produce and may provide up to double the usual service life.
A further feature of the embodiment of FIGS. 7-9 is that while the check valve(s) function in the same manner as the other embodiments, it can be seen that the upper check valve is able to be sprung (operated) from above via a connecting rod 9 a as well as from below ( FIG. 6 ). Therefore, the combination of check valve arrangements maintains the actual position of the poppet valves and seats as described throughout the disclosure but may be sprung in alternate ways.
FIGS. 7 and 8 show the embodiment in two phases, FIG. 7 being in the bit closed condition which is the operational mode, albeit shown with the check valve(s) closed whereas during normal operation they would be open as seen in FIG. 8 , illustrating the drop-open condition whereby operation is interrupted, and full flow bypass is enabled as indicated by arrows.
The description above, and the drawings, describe presently preferred embodiments of the invention. Inasmuch as the invention is subject to modification and improvement, the preferred embodiments should be regarded as examples of the invention defined by the claims below. | A down-hole hammer includes a two-piece drill bit retained in a casing having an interior surface with a plurality of longitudinal grooves formed therein. The bit shank and the casing are rotationally connected by a number of pins received in the grooves. A symmetrical free piston divides the casing into an upper working chamber and a lower working chamber. The piston slides on an air control assembly including a ported tube extending axially from said air supply to an axial bore in the shank of the bit to guide exhaust air through discharge ports at the cutting face of the bit, the bit reciprocating on the end of the tube. The upper and lower check valves in the air control assembly and openable by supply pressure against a spring bias in response to working fluid supply pressure. | 4 |
TECHNICAL FIELD
[0001] The present invention relates to a method and system for updating a plurality of computers, and particularly, but not exclusively a method of updating a plurality of computers that are located remotely to a source of the update.
BACKGROUND
[0002] During the past 10 years, IT infrastructures have experienced significant growth due to the increased availability of distributed computing environments and inexpensive and robust servers. Systems management refers to enterprise-wide administration of distributed computer systems. The main tasks involved in system management include:
deployment of new software components; update of software components (e.g., patch management); automation of standard procedures; centralised and delegated control of IT components; and monitoring of IT components; etc.
The task of system management is becoming increasingly difficult because of the ever-increasing complexity of today's IT environments and the growing use of pervasive devices (e.g. PDAs). There are a number of enterprise software distribution programs currently available (e.g., IBM's Tivoli Software Distribution program) which enable administrators to install, configure, and update software on networked systems. These software distribution programs can implement “push” (i.e. a reverse client/server or server-initiated) or “pull” (client initiated) procedures to identify non-compliant recipient devices and transmit messages thereto to cause disseminated agents on the recipient devices to execute a distribution command (e.g., installation code), possibly using associated distribution data, and thereby update their software. In a push communication procedure a request for a service is initiated by the service provider. In contrast, in a pull communication procedure, a request for a service is initiated by a requester.
[0008] It is an object of the present invention to provide an improved method and system which alleviate the drawbacks of the prior art.
SUMMARY OF THE INVENTION
[0009] According to the invention there is a method, system and product of updating a plurality of computers. A first message is created in an update source, where the first message includes a one or more instructions and an address of a message repository. The first message is transmitted to a first computer using either a Push or a Pull protocol. A second message is transmitted to the first computer using the Push or Pull protocol, the second message comprising data retrieved from the address in the first message. The first computer executes one or more of the instructions in the first message with at least some of the second message. The address in the first message is updated to match the address of the first computer. The updated first message is transmitting to a further one of the computers. Transmission of the second message is repeated to further ones in the plurality of computers until substantially all of a pre-defined number of computers have been updated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] An embodiment of the invention is herein described by way of example only, with reference to the accompanying Figures in which:
[0011] FIG. 1 is a block diagram of an exemplary enterprise network in which the method of the preferred embodiment would operate;
[0012] FIG. 2 is a block diagram of an information flow in a prior art peering distribution process;
[0013] FIG. 3 is a block diagram of an information flow in a prior art polling distribution process;
[0014] FIG. 4 is a flowchart of the method of the preferred embodiment;
[0015] FIG. 5 is a block diagram of an information flow in the Push paradigm implementation of the preferred embodiment;
[0016] FIG. 6 is a schematic diagram of a computer system adapted to support the preferred embodiment;
[0017] FIG. 7 is a flowchart of the method of the Pull paradigm implementation of the preferred embodiment;
[0018] FIG. 8 is a block diagram of an information flow in the Pull paradigm implementation of the preferred embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0019] One preferred embodiment addresses the problems of
minimizing network traffic over WAN links during a distribution process; with a pull protocol especially when there are no jobs for computers in a branch office; minimizing the use of management software and the need for management servers in branch offices, thereby reducing the operating costs of an enterprise network, since apart from their role in system management, management servers do not typically contribute to the running of a user's everyday business applications and thus, represent an expensive overhead in maintaining an enterprise network; guaranteeing scalability, reliability, high availability and resilience; and managing powered-off endpoint computers through a Wake-On-LAN (WOL) protocol.
[0024] More particularly, compared with a traditional per target distribution paradigm, a preferred embodiment avoids the need for a fan-out depot inside a branch office, since the preferred embodiment enables a first endpoint computer to:
[0025] acquire a distribution document (containing links to a repository of relevant distribution data);
[0026] download the relevant distribution data over a WAN link; and
[0027] provide other endpoint computers in the same branch office with the relevant commands and distribution data.
[0028] One preferred embodiment employs a two-way gossip protocol, which enables the status of the distribution process to be propagated to all of the endpoint computers in the branch office. More particularly, the preferred embodiment provides for the inclusion of a distribution status document in each endpoint computer in a branch office. The distribution status document effectively details the status (has/has not received distribution commands etc.) of each endpoint computer (in the branch office) to which the user has specified the distribution should occur. An endpoint computer is allowed (at any stage in the gossip protocol) to update its distribution status document to reflect the changes in its own status (or the status of other endpoint computers in the branch office). This approach has several benefits including:
enhancing the performance and scalability of the distribution process, because a management system can determine the status of the distribution in an entire branch office by a communication with a single endpoint computer therein (which, in turn, simplifies the management center protocol) strengthening the distribution process against failures of individual endpoint computers (since a management center can determine the status of the distribution from the other endpoint computers).
[0031] One preferred embodiment allows a distribution document to be resent to endpoint computers in which, for one reason or another, the distribution process has failed. Thus, any endpoint computers that failed to download the required distribution data, will have other chances to acquire the distribution document (and its links to another repository for the distribution data) from other endpoint computers participating in the gossip protocol. This adds resilience and robustness to the distribution process to enable it to withstand single failures without intervention of the management center.
[0032] Furthermore, as part of the gossip protocol of the preferred embodiment, a dormant endpoint computer can be awakened by a WOL packet, without intervention of the management center (i.e. since the endpoint computers are in the same LAN, there will be no problems of WOL packages crossing subnetwork boundaries).
[0033] On another note, one preferred embodiment is robust to distribution loss, and transient network disruptions. Finally, the preferred embodiment allows the use of simple and lightweight management centers, since the management center has a much smaller role in implementing the distribution process (i.e. since most of the communication in the distribution process is managed inside a branch office by peer endpoint computers). In particular, in its simplest implementation with a Push protocol, a management center need only send a distribution document to a randomly selected endpoint computer and wait for results (from the selected endpoint computer) detailing the status of the distribution process.
[0034] One preferred embodiment, in its pull protocol implementation, solves one problem of a conventional pull communication protocol which is that each endpoint computer polls a management centre over slow and unreliable WAN links (unless an intermediate manager, or caching server is located in the branch office) generating useless traffic most of the time. The preferred embodiment drastically reduces this traffic since in addition to propagating a distribution document to an entire branch office, an endpoint computer also informs the relevant endpoint computers when there are no distribution jobs therefor. This enables endpoint computers to reset their polling timeout to the next polling interval, so that at steady state, only one endpoint computer polls the management centre for jobs. Having reduced the traffic generated by useless polls, the polling interval can be shortened, thereby making it easier to provide immediate distributions.
[0035] Another advantage of one preferred embodiment in its Pull protocol implementation is its resilience and robustness, since there is no single point of failure. In particular, if an endpoint crashes, another endpoint computer will collect the failure in the gossip session and notify the management centre in a Distribution Results Document. In a traditional gossip system, if more than one endpoint polls a management centre for the same distribution document, a gossip session is initiated. However, in the preferred embodiment, gossip sessions are identified by a distribution ID code so that at some point, they may be joined in a single session.
1. Typical Enterprise Network Environment
[0036] Referring to FIG. 1 , an exemplary enterprise network 10 can be divided into a plurality of interconnected branch offices and data centers 14 . A branch office 12 comprises a plurality of endpoint computers 16 connected together through a branch office LAN 18 ; wherein the branch office LANs 18 are themselves connected through routers 20 to the Internet 22 . A data center 14 typically comprises a plurality of data center servers which run the applications (e.g., middleware) that handle the core business and operational data of the enterprise. The data center servers are connected together through a data center LAN 24 ; wherein the data center LANs 24 are themselves connected to the Internet 22 through routers 26 .
[0037] The enterprise network 10 is typically managed by a distributed software application known as a management system. A management system typically comprises a management center 28 , a plurality of fan-out depot servers and a plurality of management system agents. The management center 28 typically comprises a management server 30 and one or more fan-out depot servers 32 . The management server 30 provides interfaces (e.g., API, graphical user interface (GUI), command line, etc.) for administering the entire management system and for managing one or more of the endpoint computers 16 . The management server 30 and fan-out depot servers 32 are connected to each other through a management center LAN 34 , which is connected in turn to the Internet 22 through a router 36 . A management system may also include intermediate management centers for better scalability. Similarly, the management system may be capable of network segment traversal. One or more of the enterprise network data centers 14 may be configured to include fan-out depot servers 38 (connected to the data center LANs 24 ). One or more of the fan-out depot servers 38 are configured to host management system agents, wherein these agents are software components that are responsible for receiving and performing management actions (e.g., software installation, inventory data collection, operating system monitoring, etc.) in endpoint computers 16 . To this end, a management system agent is typically installed on each of the endpoint computers 16 in a branch office 12 .
[0038] Unfortunately, branch offices 12 are often located remotely to the management center 28 (and the data centers 14 housing the fan-out depot servers 38 ). To further aggravate the situation, the branch offices 12 are often connected to the management center 28 through, slow and unreliable, wide area network (WAN) links. Indeed, branch offices 12 are often disconnected from the management center 28 . Data centers 14 may also be located remotely to the management center 28 . However, in contrast with the branch offices 12 , the data centers 14 are typically connected to the management center 28 through reliable WAN/LAN links. In addition to software and data distribution, hardware and software inventories are performed on end-point computers, as are other tasks which are delivered and executed on these computers.
[0039] This architecture leads to difficulties in disseminating distribution commands and associated distribution data to branch offices and data centers. A distribution command relates to any management action (initiated from the management server), that must be performed by the management system agents (e.g., software installation, inventory data collection, upload of a data file from a managed computer to the management system). For example, a distribution command could be to invoke msiexec (which is a native Windows command used to install a software on windows platforms); or a task internally supported by agent code like “change configuration parameter x to y”. Distribution Commands are described in a distribution document. Thus, distribution commands are deployed to clients in distribution documents.
[0040] A distribution document contains information needed to perform a command (e.g., install software; run a program to remedy a problem on a client computer, etc.). In general, a distribution document fully describes the operation that an agent code must perform. Distribution documents are typically small in size, making them particularly suitable for exchange in a gossip session.
[0041] Distribution data is any data that is not contained in a distribution document and that might be required to execute a distribution command (e.g., software installation often requires software images to be deployed to endpoint computers and deleted therefrom when the installation is complete) in a distribution document. For example, to execute msiexec it is not necessary to download msiexec.exe because it is already on client computers. In contrast, ciccio.exe must be downloaded before it can be executed, because it is not in the client computer, nor is it a part of the operating system of the agent code. Fan-out distribution refers to the process of downloading distribution data from fan-out depot servers to endpoint computers. A distribution document describes a list of fan-out depot servers which contain distribution data and that can be contacted by the agent code for download.
2. Problems with Conventional Distribution Procedures
[0042] Modern approaches to solving the fan-out distribution problem include:
(i) Installing a Depot Server in a Branch Office
[0043] In this approach, the depot server receives bulk data and distributes it to the endpoint computers. However, this requires the deployment and maintenance of management servers in branch offices.
(ii) Enabling Peering Capabilities in Agent Software
[0044] Referring to FIG. 2 , in this approach, an endpoint computer (EC) can become the source of distribution commands and distribution data for other endpoint computers (EC) in the branch office. This has the advantage of limiting the traffic on the WAN links (between the endpoint computers and the management center) because comparatively few endpoint computers effectively acquire their distribution data from outside the branch offices (since the other endpoint computers acquire the distribution commands and distribution data from their peers in the branch office).
[0000] (iii) Polling
[0045] A polling paradigm has been recently used to achieve scalability in large-scale distributed environments. Referring to FIG. 3 , in this approach, endpoint computers EC 1 -EC 3 periodically poll the management center MC (or some intermediate cache servers) to acquire distribution documents.
[0046] On receipt of the distribution documents, the endpoint computers EC 1 -EC 3 contact a designated repository S for the relevant distribution data. This approach is the opposite of a push paradigm, wherein the management center MC effectively pushes the distribution documents to target endpoint computers EC 1 -EC 3 .
[0047] The polling paradigm allows scalable infrastructures to be implemented because the distribution load is spread across the management center MC and depot servers S. In particular, the polling paradigm ensures that all of the endpoint computers EC do not contact the management center MC at the same time, because the polling process is randomly distributed over time. While pull-based technology makes system management products more scalable and firewall-friendly than those based on push technology, nonetheless, it has a number of limitations that make it difficult to minimize network traffic and the use of management software in branch offices. In particular, because of the polling interval of the polling paradigm, it is difficult to immediately deliver a distribution document to endpoint computers. This facility is important for the installation of emergency security patches.
[0048] Similarly, whilst each endpoint computer polls a management center for distribution documents, since distribution documents are only periodically deployed, the endpoint computers rarely receive distribution jobs in response to their polls. Thus, most of the network traffic generated by polling is useless. Furthermore, users tend to shorten polling periods (in an effort to achieve “near” immediate distributions), thereby increasing polling traffic. A possible solution to this problem would be to install a caching server in branch offices. However, this would counter the aim of a reducing management apparatus in branch offices.
[0049] Furthermore, the push and polling paradigms have a fundamental limitation, namely a distribution document per target limit. In these prior art approaches a first computer which acquires distribution data from outside the branch office (from the depot server) will cache the data. Similarly, when another computer in the branch office acquires a distribution document, it will first try to get distribution data from a peer computer, and then from a depot server. Thus, all the endpoint computers effectively get their distribution documents from a management server. In other words, peering is not applied to the distribution commands to be executed but only to the distribution data that are needed to execute the distribution commands.
[0050] Accordingly, network traffic over slow links is only reduced for distribution data, since distribution documents still traverse WAN links for each target endpoint computer EC 1 -EC 3 in a branch office. This problem is emphasized with the polling paradigm, wherein network traffic over WAN links is increased (as compared with the push paradigm), because each endpoint computer EC 1 -EC 3 polls outside of the branch office (i.e. to the management center MC) for distribution commands and distribution data. On another note, with the polling paradigm it is impossible to send software and/or to a powered-off endpoint computer. In contrast, the push paradigm allows a dormant endpoint computer to be activated with a WOL packet.
3. Overview of the Preferred Embodiment
[0051] The preferred embodiment overcomes the above-mentioned problems with the distribution document per target paradigm by using a distribution document per branch office paradigm. In particular, the preferred embodiment addresses an entire branch office or a subset of endpoint computers therein, rather than its individual endpoint computers.
[0052] The preferred embodiment uses a gossip protocol, which is a computer-to-computer communication protocol inspired by the form of gossip seen in social networks (Agrawal et al., Advances in Multimedia 2007 (2007), Article ID 84150). More particularly, a gossip protocol is a protocol designed to mimic the way that information spreads when people gossip about something. For example, in a push gossip protocol a node communicates information to another node. In a human analogy, suppose that I know something and I am sitting next to Jim. If I tell Jim about that the topic, then two of us know about it. If later on, Jim tells John about the topic and I tell another person Mike about it, then four of us know about it; and so the information is disseminated rapidly through a group of people. A gossip protocol is said to be a pull gossip protocol if a node asks an information from another node. Finally, a gossip protocol is said to be push and pull gossip protocol, if it exhibits both of the above behaviors. In particular, a gossip protocol is said to be push and pull protocol when two nodes exchange information in an interactive fashion. For simplicity, a node which transmits information to another node, will be known henceforth as a gossiping node. Similarly, a node which receives the information will be known as a gossiped node.
[0053] In view of the present distribution application, a group of endpoint computers to whom a distribution is to be conducted, will be known henceforth as a distribution population. It will be understood, that a user may wish to select the members of a given distribution population by other criteria than their location. For example, a user may wish to perform a particular distribution operation on endpoint computers running a particular version of a software product, wherein the endpoint computers are located in different branch offices.
4. Push Paradigm Implementation of Preferred Embodiment
[0054] Referring to FIG. 4 and FIG. 5 in combination, a simplified example of a fan-out distribution using the push paradigm comprises the steps of:
[0055] (a) the management center partitioning a population distribution into a plurality of segments, wherein each segment corresponds with the members of a single branch office;
[0056] (b) the management center (MC) selecting 40 a first endpoint computer (EC 1 ) in a given segment;
[0057] (c) the management center (MC) transmitting 42 a distribution document (Dist_Doc) to the first endpoint computer (EC 1 ) wherein the distribution document (Dist_Doc) describes:
the other endpoint computers (EC 2 , EC 3 ) in the same segment; the distribution command to be executed in the endpoint computers (e.g., software installation, inventory collection); and a URL of the repository (S) for the relevant distribution data (e.g., fan-out depot server);
[0061] d) the first endpoint computer (EC 1 ) returning a distribution status document (Stat_Doc) to the source computer (i.e. the management center in this case) indicating whether the download was successful;
[0062] (e) the first endpoint computer (EC 1 ) contacting (Req) the designated repository (S) (using the fan-out URL from the distribution document [Dist_Doc]) and downloading 44 the distribution data (Data) therefrom; and simultaneously initiating a push and pull gossip protocol session with other endpoint computers (EC 2 , EC 3 ) in the segment by:
(1) amending 46 the distribution document (Dist_Doc) to add its own URL as the source for the distribution data (Data) so peer computers will download data from it rather than going out of the branch office (this ensures robustness because if the source client computer crashes, there are other sources of data indicated in the distribution document and only in that case will a client computer go out of its branch office to acquire data); (2) randomly selecting a second endpoint computer (EC 2 ) in the segment; and (3) sending 48 the amended distribution document (Dist_Doc) and its distribution status document (Stat_Doc) to the second endpoint computer (EC 2 );
[0066] (f) a management system agent in the first endpoint computer (EC 1 ) executing the distribution command(s);
[0067] (g) the second endpoint computer (EC 2 ) updating its distribution status document (Stat_Doc) to reflect the distribution status document (Stat_Doc) received from the first endpoint computer (EC 1 );
[0068] (h) the second endpoint computer (EC 2 ) returning a distribution status document (Stat_Doc) to the first endpoint computer (EC 1 ) indicating the success, or otherwise of the download operation;
[0069] (i) the first endpoint computer (EC 1 ) updating its distribution status document (Stat_Doc) to reflect the distribution status document (Stat_Doc) received from the second endpoint computer (EC 2 );
[0070] (j) the second endpoint computer (EC 2 ) contacting (Req) the first endpoint computer (EC 1 ) and downloading 49 therefrom distribution data (Data), whilst simultaneously amending the distribution document (Dist_Doc) to add its own URL as the source for the distribution data (Data); and sending the amended distribution document (Dist_Doc) to a third endpoint computer (EC 3 ) in the segment, in a similar fashion to step (e); and
[0071] (k) a management system agent in the second endpoint computer (EC 2 ) executing the distribution commands.
[0072] The above download and document exchange process is continued for several iterations until an endpoint computer receives distribution status document (Stat_Doc) indicating a final status condition (e.g. success, failure, endpoint computer unavailable). At this point, the relevant endpoint computer returns 50 a distribution status document (Stat_Doc) indicating the status condition to the management center (MC). The management center (MC) reviews the distribution status document (Stat_Doc) to determine whether the distribution data (Data) have been deployed to all of the members of the branch office. If so, the distribution operation is deemed to have been completed for the branch office; and the management center (MC) selects another segment of the distribution population and re-starts the distribution process therein. However, if the distribution data (Data) have not been deployed to all of the members of the branch office, the management center (MC) selects another candidate endpoint computer and re-transmits the original distribution document (Dist_Doc) (listing the URL of the repository as the source of the distribution data) thereto.
[0073] In another implementation, on receipt (by an endpoint computer) of a distribution status document (Stat_Doc) indicating an error condition, the endpoint computer reviews the nature of the error condition. In particular, if the distribution status document (Stat_Doc) indicates that all the endpoint computers in the segment received distribution data (Data), the endpoint computer will stop the gossip session and return the relevant distribution status document (Stat_Doc) to the management center (MC). Otherwise, the endpoint computer is switched to a dormant state and reawakened after a pre-defined time interval to randomly select another endpoint computer and transmit its distribution status document (Stat_Doc) and distribution document (Dist_Doc) thereto.
[0074] In addition, the management center (MC) may directly interrogate an endpoint computer to determine the status of the distribution operation, since because of the two-way nature of the gossip protocol, the distribution status document (Stat_Doc) in each endpoint computer essentially details the status of each of the other endpoint computers in their branch office.
[0075] In one possible implementation of this interrogation procedure, the management center (MC) switches to an inactive state after transmitting the distribution document (Dist_Doc) (listing the URL of the repository (S) as the source of distribution data (Data) to the selected first endpoint computer. The management center (MC) is then periodically reactivated, to interrogate the first endpoint computer and thereby determine the extent to which the required distribution process has been completed. If after a pre-defined period of time:
the distribution data (Data) have not been deployed to all of the endpoint computers in the branch office; or there has not been a significant change in the number of endpoint computers to which the distribution data (Data) have been deployed; the management center (MC) restarts the distribution process as discussed above. By restarting the distribution process in this fashion, the preferred embodiment ensures that the distribution data (Data) propagate through a branch office regardless of endpoint computer failures.
[0079] In yet another embodiment, a management center (MC) does not wait for the receipt of a distribution status document indicating an error condition before restarting the distribution process. Instead, the management center periodically wakes from a dormant state and automatically restarts the distribution process. In this embodiment, the endpoint computers do not themselves advise the management center of the success so far of the distribution process. Instead, the management center itself automatically acquires the results on receipt of a distribution status document (Stat_Doc) on restarting the distribution process.
5. Pull Paradigm Implementation of Preferred Embodiment
[0080] In essence, the method of the preferred embodiment involves a management centre publishing a distribution document for each branch office; and a first endpoint computer polling the management centre for distribution documents and propagating the information to the entire branch office. Referring to FIGS. 7 and 8 , an implementation of the preferred embodiment comprises the steps of:
[0081] (a) endpoint computers (EC 1 , EC 2 , EC 3 ) periodically polling (POLL 1 , POLL 2 , POLL 3 ) the management centre (MC) for jobs to do (the polling times of the endpoint computers being uniformly distributed in a polling interval, to spread the load on the management centre (MC));
[0082] (b) the management centre (MC) partitioning 740 a distribution job into a plurality of segments;
[0083] (c) the management centre (MC) creating 742 a distribution document (Dist_Doc) for each segment, wherein the distribution document (Dist_Doc) describes:
endpoint computers (EC 1 , EC 2 , EC 3 ) in the segment; distribution commands to be executed in the endpoint computers (e.g., software installation, inventory collection); and a URL of the repository (S) for associated distribution data (e.g., fan-out depot server).
[0087] (d) a first endpoint computer (EC 1 ) contacting the management centre (MC) and requesting 744 a distribution document (Dist_Doc);
[0088] (e) the management centre (MC) transmitting 746 the distribution document (Dist_Doc) to the first endpoint computer (EC 1 );
[0089] (f) the first endpoint computer (EC 1 ) suspending 748 its polling of the management centre (MC) for the duration of its distribution operation; and
[0090] (g) the first endpoint computer (EC 1 ) contacting (Req) the designated repository (S) (using the fan-out depot URL from the distribution document ((Dist_Doc)) and downloading 750 the distribution data (Data) therefrom; and simultaneously initiating a push and pull gossip protocol session with other endpoint computers (EC 2 , EC 3 ) in the segment by:
(1) amending 754 the distribution document (Dist_Doc) to add its own URL as the source for distribution data (Data), so peer computers will download data from it rather than going out of the branch office; (2) randomly selecting a second endpoint computer (EC 2 , EC 3 ) in the segment; and (3) sending 756 the amended distribution document (Dist_Doc) and the distribution status document (Stat_Doc) to the second endpoint computer (EC 2 );
[0094] (h) a management system agent in the first endpoint computer (EC 1 ) executing the distribution command(s);
[0095] (i) the second endpoint computer (EC 2 ) suspending 758 its polling of the management centre (MC) for the duration of its distribution operation;
[0096] (j) the second endpoint computer (EC 2 ) contacting the first endpoint computer (EC 1 ) and downloading 760 distribution data (Data) therefrom; and simultaneously initiating another iteration of the gossip session, using steps (g)(1) to (g)(3);
[0097] (k) the second endpoint computer (EC 2 ) updating its distribution status document (Stat_Doc) to reflect the distribution status document (Stat_Doc) received from the first endpoint computer (EC 1 );
[0098] (l) a management system agent in the second endpoint computer (EC 2 ) executing the distribution commands; and
[0099] (m) the second endpoint computer (EC 2 ) returning a distribution status document (Stat_Doc) to the first endpoint computer (EC 1 ) indicating the success, or otherwise of the download operation; and
[0100] (n) the first endpoint computer (EC 1 ) updating its distribution status document (Stat_Doc) to reflect the distribution status document (Stat_Doc) received from the second endpoint computer (EC 2 ).
[0101] At each stage in the gossip session, the endpoint computers receive copies of updated distribution status documents, (which provide information on the status of download process in the individual endpoint computers in the branch office). Accordingly, a given distribution status document provides a detailed overview of the status of the distribution operation in the branch office at a given time. An endpoint computer stops gossiping when it receives a distribution status document indicating a final status condition (e.g., success, failure, endpoint computer unavailable). The relevant endpoint computer then returns a distribution result document to the management centre (MC). If the required distribution is not complete, the endpoint computer requests a new distribution document from the management centre (MC). It should be noted that with this approach, the management centre does not receive information regarding the success of the distribution process, until the occurrence of an final status condition. Accordingly, this approach does not allow the management centre (MC) to report and track the progress of the distribution operation. However, in an alternative implementation, an endpoint computer is configured to gossip a distribution status document to the management centre (MC) in addition to their endpoint computer gossip partner.
[0102] In the event that no distribution document has been assigned to a branch office, an endpoint computer polling a management centre (MC) for a distribution document receives a Null Distribution Document, which lists the endpoint computers in the branch office. This information is useful, because in its absence, an endpoint computer would have no way of knowing the details of other endpoint computers in the branch office. On receipt of a Null Distribution Document, an endpoint computer initiates a push & pull gossip protocol session with the other endpoint computers in the branch office, passing the Null Distribution Document therebetween. A recipient endpoint computer resets its polling timeout choosing a random number (N) in the interval [T0+Dt; T0+2*Dt], wherein Dt=polling interval and T0=the present time. An endpoint computer stops gossiping when it receives feedback from all of the endpoint computers in the branch office (apart from unavailable endpoint computers).
[0103] Thus, in summary, a management centre (MC) transmits a distribution document to an endpoint computer (or a Null distribution document if there is no operation queued for the branch office). Similarly, an endpoint computer transmits a distribution result document to the management centre (MC).
[0104] An endpoint computer polls the management centre:
[0105] (a) when a polling timeout occurs (i.e. the endpoint computer was idle); or
[0106] (b) at the end of a distribution process, (when the endpoint computer collects the final distribution result document and needs to transmit it back to the management centre). After a polling session, an endpoint computer initiates a gossip session in the branch office during which propagates a new distribution document, or propagates a null distribution document, (whose effect is to reset the polling time of other endpoint computers as explained above). In both cases, an endpoint computer informs its peers if it transmits a last distribution result document to the management centre.
6. Generic Computer Structure
[0107] Referring to FIG. 6 , a generic computer system 51 adapted to support the preferred embodiments is formed by several units that are connected in parallel to a system bus 52 . In detail, one or more microprocessors (lP) 54 control operation of the computer 51 ; a RAM 56 is directly used as a working memory by the microprocessors 54 , and a ROM 58 stores basic code for a bootstrap of the computer 51 . Peripheral units are clustered around a local bus 60 (by means of respective interfaces). Particularly, a mass memory consists of a hard-disk 62 and a drive 64 for reading CD-ROMs 66 . Moreover, the computer 51 includes input devices 68 (for example, a keyboard and a mouse), and output devices 70 (for example, a monitor and a printer). A Network Interface Card (NIC) 72 is used to connect the computer 51 to the network. A bridge unit 74 interfaces the system bus 52 with the local bus 60 . Each microprocessor 54 and the bridge unit 74 can operate as master agents requesting an access to the system bus 52 for transmitting information. An arbiter 76 manages the granting of the access with mutual exclusion to the system bus 52 .
[0108] Similar considerations apply if the system has a different topology, or it is based on other networks. Alternatively, the computers have a different structure, include equivalent units, or consist of other data processing entities (such as PDAs, mobile phones, and the like).
[0109] Alterations and modifications may be made to the above without departing from the scope of the invention. | Updating a plurality of computers is accomplished. A first message is created in an update source, where the first message includes a one or more instructions and an address of a message repository. The first message is transmitted to a first computer using either a Push or a Pull protocol. A second message is transmitted to the first computer using the Push or Pull protocol, the second message comprising data retrieved from the address in the first message. The first computer executes one or more of the instructions in the first message with at least some of the second message. The address in the first message is updated to match the address of the first computer. The updated first message is transmitting to a further one of the computers. Transmission of the second message is repeated to further ones in the plurality of computers until substantially all of a pre-defined number of computers have been updated. | 7 |
CROSS-REFERENCE
[0001] The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/369,344, entitled ‘Transport Tank Baffle Assembly’, filed Jul. 30, 2010, the entirety of which is incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to baffle assemblies for transport tanks for trucks.
BACKGROUND
[0003] Many industries use trucks for the transportation of their goods. To transport a liquid, a truck is provided with a transport tank mounted to a frame of the truck or to a trailer of the truck. When the liquid is to be transported under pressure, the transport tank needs to be constructed to withstand this pressure. One example of such a liquid is a liquefied petroleum gas, such as propane. Typically, in order to withstand internal pressures, transport tanks are made of metal, such as carbon or stainless steel, and have a cylindrical central section and two generally curved ends. Although metal transport tanks such as the one described above are suitable for the transport of pressurized liquids they have some drawbacks.
[0004] In most jurisdictions, the total truck weight (truck plus payload) or total trailer weight (trailer plus payload) is not allowed to exceed a predetermined maximum weight. As a metal transport tank is heavy, the maximum weight of the payload that can be transported is less than could otherwise be transported if the transport tank was lighter. Also, a metal transport tank tends to corrode over time which requires maintenance, repair, and in some cases replacement of the tank.
[0005] One solution to the above-mentioned drawbacks of metal transport tanks consist in making the transport tank out of composite material. For tanks of the same volume, composite transport tanks are lighter than metal transport tanks. As a result, by using a composite transport tank, the maximum weight of the payload that can be transported can be increased. Also, composite materials are typically less susceptible to corrosion than metals.
[0006] When transporting liquids, tanks can be subjected to sloshing. Sloshing is the motion of liquid against the tank's walls, due to inertia forces. Sloshing appears, for example, when the truck accelerates or brakes. When a liquid sloshes, great forces are generated at the tank's wall on which the liquid is projected, which may render the truck unstable and/or difficult to control.
[0007] One way to decrease sloshing is to dispose within the tank one or more baffles. The baffles break the motion of the liquid, which in turn decreases the forces generated by sloshing. Some baffles are fixed to the tank. When fixed to the tank, the baffles have to be securely fixed to the tank wall with sufficient strength to sustain the forces generated by the sloshing. When the tank is made of metal, it is usual to weld the baffles or the baffle connectors to the tank. However, when the tank is not made of metal, welding, in the same manner as for metal tanks, can lead to zones of stresses at the weld which ultimately may break off the connection between the baffle and the tank when the baffles are subjected to the sloshing forces. In addition, it is desirable that the baffles be removable to allow inspection and cleaning of the tank.
[0008] Therefore, there is a need for a transport tank with a baffle, removably connected to the tank, where the divider or baffle would in addition be adapted for use in composite tanks.
SUMMARY
[0009] It is an object of the present invention to ameliorate at least some of the inconveniences present in the prior art.
[0010] In one aspect, a lined transport tank for mounting to a truck is provided. The tank comprises a lined tank body having an inner surface. A baffle is removably connected to the inner surface of the tank body. A retaining system is removably connecting the baffle to the inner surface of the tank body. The retaining system comprises a pair of elongated members fixedly connected to the inner surface of the tank body. The pair of elongated members is restraining movement of the baffle in a first direction. A retainer is connected to the pair of elongated members. The retainer is restraining movement of the baffle in a second direction. The second direction is different from the first direction.
[0011] In a further aspect, the tank body has a cylindrical section. The first direction is a longitudinal direction with respect to the cylindrical section. The second direction is a circumferential direction with respect to the cylindrical section.
[0012] In an additional aspect, the pair of elongated members is generally perpendicular to a longitudinal centerline of the tank body.
[0013] In a further aspect, when the tank is mounted onto the truck, the pair of elongated members is disposed vertically above a lowest point of the inner surface of the tank body.
[0014] In an additional aspect, the retainer is fixedly connected to the pair of elongated members.
[0015] In a further aspect, the retainer includes a pair of tabs. The tabs connect the elongated members together. The baffle is disposed at least in part between the tabs.
[0016] In an additional aspect, the baffle has a first end and a second end. The retaining system is a first retaining system. The first retaining system removably connects the first end of the baffle to the inner surface of the tank body. A second retaining system is removably connecting the second end of the baffle to the inner surface of the tank body.
[0017] In a further aspect, the retaining system further comprises a baffle connector having a first end and a second end. The first end of the baffle connector is removably connected to the baffle. The second end of the baffle connector is disposed at least in part between the pair of elongated members. The pair of elongated members restrains movement of the baffle connector in the first direction. The retainer restrains movement of the baffle connector in the second direction.
[0018] In an additional aspect, the second end of the baffle connector has outwardly extending tabs. The tabs are disposed radially between the retainer and the tank body.
[0019] In a further aspect, the retainer abuts the baffle connector for restraining movement of the baffle connector from moving in the second direction.
[0020] In an additional aspect, the first end of the baffle connector is fastened to the baffle.
[0021] In a further aspect, the baffle connector is spaced from the inner surface of the tank body.
[0022] In an additional aspect, a wear element is disposed between the second end of the baffle connector and the inner surface of the tank body. The second end of the baffle connector is abutting the wear element.
[0023] In a further aspect, the baffle comprises a first sub-baffle and a second sub-baffle. The first and second sub-baffles are removably connected to the baffle connector.
[0024] In an additional aspect, the baffle is received at least in part between the pair of elongated members.
[0025] In a further aspect, the baffle has outwardly extending tabs, and the tabs are disposed radially between the retainer and the tank body.
[0026] In another aspect, a retaining system for removably connecting an element to a surface is provided. The retaining system comprises a connector having a first end and a second end. The first end is adapted to be removably connected to the element. A pair of elongated members is adapted to be fixedly connected to the surface. The second end of the connector is disposed at least in part between the pair of elongated members. The pair of elongated members is restraining movement of the connector in a first direction. A retainer is connected to the pair of elongated members. The retainer is restraining movement of the connector in a second direction. The second direction is different from the first direction.
[0027] For purposes of this application, the adjective “composite”, such as in “composite tank body”, indicates that the associated element is made at least in part of composite materials. Examples of composite materials include, but are not limited to, carbon fibers with epoxy resin and aramid fibers with acrylate-based resin. The term “baffle” refers to an obstruction for deflecting the flow of liquid.
[0028] Embodiments of the present invention each have at least one of the above-mentioned aspects, but do not necessarily have all of them.
[0029] Additional and/or alternative features, aspects, and advantages of embodiments of the present invention will become apparent from the following description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] 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:
[0031] FIG. 1 is a left side elevation view of a truck having a transport tank;
[0032] FIG. 2 is a perspective view taken from a rear, right side of the transport tank and a portion of a frame of the truck of FIG. 1 ;
[0033] FIG. 3 is a left side elevation view of the transport tank of FIG. 1 ;
[0034] FIG. 4 is a bottom plan view of the transport tank of FIG. 3 ;
[0035] FIG. 5 is a rear elevation view of the transport tank of FIG. 3 ;
[0036] FIG. 6 is a rear elevation view of a liner of the transport tank of FIG. 3 ;
[0037] FIG. 7 is a right side elevation view of the liner of FIG. 6 ;
[0038] FIG. 8 is an exploded view of a pipe and valve assembly for attachment to a spray fill fitting of the transport tank of FIG. 3 ;
[0039] FIG. 9 is an exploded view of a pipe and valve assembly for attachment to a vapor fitting of the transport tank of FIG. 3 ;
[0040] FIG. 10 is a cross-sectional view of the tank taken along line 10 - 10 of FIG. 3 , revealing a baffle assembly according to a first embodiment;
[0041] FIG. 11 is a perspective close-up view of the baffle assembly and tank of FIG. 10 ;
[0042] FIG. 12 is an exploded view of a baffle and a retaining system of the baffle assembly of FIG. 10 ;
[0043] FIG. 13 is a schematic, partial side view of the connection to the tank of the baffle assembly of FIG. 10 ;
[0044] FIG. 14 is an exploded view of a baffle and a retaining system of a baffle assembly according to a second embodiment;
[0045] FIG. 15 is an exploded view of a baffle and a retaining system of a baffle assembly according to a third embodiment;
[0046] FIG. 16 is an exploded view of a baffle and a retaining system of a baffle assembly according to a fourth embodiment;
[0047] FIG. 17 is an exploded view of a baffle and a retaining system of a baffle assembly according to a fifth embodiment; and
[0048] FIG. 18 is a schematic, partial side view of a connection to the tank of the baffle assembly of FIG. 17 .
DETAILED DESCRIPTION
[0049] A truck 10 having a transport tank 12 in accordance with aspects of the present invention will be described with respect to FIG. 1 . The truck 10 has a frame 14 to which a cabin 16 , two axles 18 , an engine (not shown), and the tank 12 are connected. The engine is covered by a hood 20 . The engine drives at least one of the two axles 18 . A plurality of wheels 22 are mounted to the axles 18 . It is contemplated that the truck 10 could have more than two axles 18 .
[0050] As seen in FIG. 2 , the tank 12 is connected to the frame 14 of the truck 10 via three cradle assemblies 24 . It is contemplated that more or less than three cradle assemblies 24 could be used. The cradle assemblies 24 are bonded to an outer side of a body 26 of the tank 12 . Two L-bars 28 are connected to the cradle assemblies 24 and are fastened to the frame 14 . It is contemplated that the cradle assemblies 24 could alternatively be fastened or otherwise connected to the tank 12 . It is also contemplated that the cradle assemblies 24 could be connected to the frame 14 by other means, such as by welding the cradle assemblies 24 directly to the frame 14 .
[0051] It is contemplated that the truck 10 could have a flatbed mounted to the frame 14 . In such an embodiment, the tank 12 would be mounted to the flatbed. It is also contemplated that the tank 12 could be mounted to a truck of a different type than the truck 10 shown in FIG. 1 . For example, the truck could be a tractor-trailer consisting of a tractor and of a full trailer or semitrailer hooked to the tractor. In such an embodiment, the tank would be mounted to the full trailer or semitrailer.
[0052] Turning now to FIGS. 2 to 5 , the tank 12 will be described in more detail. The tank body 26 has a cylindrical central section 30 closed by two generally curved ends 32 , 34 . It is contemplated that the tank body 26 could be shaped so as to have a non-circular lateral cross-section, such as an ellipsoidal lateral cross-section. A man-way is formed in the rear end 32 of the tank body 26 to permit the passage of a person inside the tank 12 for maintenance, cleaning, and assembly of components of the tank 12 . The man-way is closed by a cover 36 which is fastened by a plurality of threaded fasteners 38 . As best seen in FIG. 5 , a float gauge 40 is inserted in an aperture in the center of the cover 36 . The float gauge 40 provides an indication of the level of liquid in the tank 12 . A temperature gauge 42 is inserted in another aperture in the cover 36 . The temperature gauge 42 provides an indication of the temperature of the liquid in the tank 12 .
[0053] A number of fittings 44 , 46 and 48 are provided in the rear end 32 of the tank body 26 below the man-way cover 36 . The fittings 44 , 46 and 48 are made of carbon steel. However, it is contemplated that the fittings 44 , 46 and 48 could be made of other types of metal or of plastic, such as fiber reinforced plastic.
[0054] The two fittings 44 are referred to as spray fill fittings 44 . A pipe and valve assembly 50 , shown in FIG. 8 , is connected to the outer end of the fittings 44 . As shown in FIG. 8 , the assembly 50 has a back pressure check valve 52 . The valve 52 is threaded into the spray fill fitting 44 and prevents vapor from flowing out of the tank 12 . A bushing 54 is threaded into the valve 52 . A pipe 56 has one end threaded in the bushing 54 and another end threaded in an end of a manually operated valve 58 . An adaptor 60 is threaded in the other end of valve 58 . A plug 62 fits into a hole 64 in the side of the adaptor 60 . The hole 64 gives an operator of the truck 10 the ability to install a vent valve and release pressure between the valve 58 and a removable cap 66 before connecting a fill hose. The removable cap 66 is threaded on the end of the adaptor 60 . The cap 66 is connected to the tank 12 or truck 10 by a chain 68 to prevent the cap 66 from being misplaced when it is removed from the end of the adaptor 60 . In the interior of the tank 12 , pipes (not shown) are connected to the spray fill fittings 44 . The pipes are suspended from the top of the tank body 26 , as described in greater detail below, such that the outlets of the pipes are higher than the fittings 44 . To fill the tank 12 , the cap 66 is removed from the adaptor 60 . A fill hose from a storage tank holding the liquid to be put in the tank 12 is connected to the adaptor 60 . The valve 58 is then opened and a pump turned on to pump liquid through the assembly 50 into the pipe and is finally sprayed inside the tank 12 (hence the name spray fill fitting for the fitting 44 ). Once the desired amount of liquid is in the tank 12 , the pump is turned off, the valve 58 is closed and the cap 66 is threaded back on the adaptor 60 . The above is simply a general description of the major steps necessary to fill the tank 12 . It should be understood that additional steps could be necessary. By providing two spray fill fittings 44 , it is possible to fill the tank 12 faster.
[0055] The fitting 46 is referred to as a vapor fitting 46 . A pipe and valve assembly 70 , shown in FIG. 9 , is connected to the outer end of the fittings 46 . As shown in FIG. 9 , the assembly 70 has a valve 72 . The valve 72 is threaded into the vapor fitting 46 and prevents vapor from accidentally releasing from the tank 12 . A pipe 74 has one end threaded in the valve 72 and another end threaded in an end of a manually operated valve 76 . An adaptor 78 is threaded in the other end of valve 76 . A removable cap 80 is threaded on the end of the adaptor 78 . The cap 80 is connected to the tank 12 or truck 10 by a chain 82 to prevent the cap 80 from being misplaced when it is removed from the end of the adaptor 78 . In the interior of the tank 12 , a pipe (not shown) is connected to the vapor fitting 46 . By removing the cap 80 from the adaptor 78 and by opening the valve 76 , the operator can release vapor pressure from inside the tank 12 .
[0056] The fitting 48 receives a pressure gauge (not shown) connected to a tube (not shown) disposed inside the tank 12 and a manual valve (not shown). The tube has an opened end disposed inside the tank 12 at a level corresponding to 85% of the volume of tank body 26 . When the level of liquid inside the tank body 26 reaches the end of the tube, the tank body 26 is 85% full. The operator can see that this volume is reached by opening the manual valve and determining if liquid is present in the valve. It is contemplated that this level may vary depending on local regulations.
[0057] A number of fittings 84 and 86 are provided in the top of the tank body 26 along the longitudinal centerline of the tank 12 . It is contemplated that the fittings 84 and 86 could be offset from the centerline of the tank 12 . The fittings 84 and 86 are made of carbon steel. However, it is contemplated that the fittings 84 and 86 could be made of other types of metal or of plastic, such as fiber reinforced plastic.
[0058] The two fittings 84 each hold a hanger (not shown) which extends inside the tank body 26 . The hangers hold the various pipes and tubes described above inside the tank body 26 .
[0059] The fitting 86 receives a pressure relief valve (not shown). The pressure relief valve opens when a predetermined pressure is reached inside the tank body 26 thus preventing the tank body 26 from becoming over pressurized.
[0060] As seen in FIGS. 3 to 5 , a pump 88 is mounted to a bottom of the tank body 26 . The pump 88 is used to pump liquid out of the tank 12 . The pump 88 is laterally offset from the longitudinal centerline of the tank 12 in order to facilitate operation of the pump 88 and so as not to interfere with other components of the truck 10 such as the frame 14 . However, it is contemplated that the pump 88 could be mounted along the longitudinal centerline or at any other position on the tank body 26 depending on the structure of the truck 10 on which the tank 12 is mounted. The pump 88 is mounted to the tank body 26 via a pump mounting assembly 90 .
[0061] Since the pump 88 is offset from the longitudinal centerline of the tank 12 , the inlet to the pump 88 provided in the pump mounting assembly 90 is located higher than the lowest portion of the tank body 26 . As such, the pump 88 cannot pump all of the liquid out of the tank body 26 . To allow removal of all of the liquid from the tank body 26 , a drain fitting 92 ( FIG. 4 ) is provided in the bottom of the tank body 26 along the longitudinal centerline of the tank 12 . The drain fitting 92 is made of carbon steel. However, it is contemplated that the drain fitting 92 could be made of other types of metal or of plastic, such as fiber reinforced plastic. The drain fitting 92 is closed by a threaded plug 94 ( FIG. 4 ). By removing the threaded plug 94 , the content of the tank body 26 can be drained by the drain fitting 92 .
[0062] The structure and construction of the tank 12 will now be described in more detail. The tank body 26 is made of a liner 96 , shown in FIGS. 6 and 7 , disposed inside a composite outer shell 98 , shown in FIG. 10 , thus forming a composite tank body 26 .
[0063] As shown in FIG. 7 , the liner 96 has a cylindrical central section 100 and two generally curved ends 102 , 104 . The liner 96 is made of high density polyethylene (HDPE) and is formed by a rotational molding process. The liner 96 is non-permeable. It is contemplated that the liner 96 could be made of another type of polymer. It is also contemplated that the liner 96 could be made of metal or other material. It is also contemplated that the liner 96 could be made by another type of process, such as blow-molding. It is also contemplated that the liner 96 could be permeable. A man-way fitting (not shown) is bonded around an aperture in the end of the generally curved end 102 of the liner 96 . In the finished tank 12 , the man-way cover 36 is bolted onto the man-way fitting.
[0064] The outer shell 98 is then formed by winding carbon fibers impregnated with epoxy resin around the liner 96 . The carbon fibers are wound helically (i.e. at an acute angle to the longitudinal central axis of the liner 96 ) and circumferentially (i.e. generally perpendicularly to the longitudinal central axis of the liner 96 ) around the liner 96 so as to cover the liner 96 . The angles at which the carbon fiber helical and circumferential windings are applied and the number of layers to be applied depend on the size of the tank body 26 , the amount of internal pressure that the tank body 26 needs to withstand, and the specific material characteristics of the carbon fiber and resin being used. It is contemplated that other types of composite materials could be used, such as aramid fibers impregnated with resin. It is contemplated that the fibers could be wound dry and that resin could be applied to the fibers as they are being wound or after a certain number of windings have been wound around the liner 96 . Some of the windings cover portions of the man-way fitting and hold it in place.
[0065] A number of outer bosses 108 , 110 , 112 and 114 are mounted on the outer side of the tank body 26 in the areas where the fittings 44 , 46 , 48 , 84 , 86 , and 92 will be located. The outer bosses 108 , 110 , 112 and 114 are formed by laying additional layers of carbon fibers impregnated with epoxy resin to these areas. The number of layers and the angles at which the fibers are laid for each outer boss 108 , 110 , 112 and 114 depend on the dimensions of the apertures to insert each of the fitting 44 , 46 , 48 , 84 , 86 , and 92 and the strength characteristics of the tank body 26 in the area where each of the fittings 44 , 46 , 48 , 84 , 86 , and 92 will be located. It is contemplated that the outer bosses 108 , 110 , 112 and 114 could also be formed by polymeric, metallic, or composite cores covered by carbon fibers and resin or other composite material. It is contemplated that the outer bosses 108 , 110 , 112 and 114 could also be formed by interspersing layers of carbon fiber and resin between windings forming the outer shell 98 of the tank body 26 .
[0066] Due to the relative proximity of the apertures for the fittings 44 , 46 and 48 , these apertures are provided with a common outer boss 108 . However, it is contemplated that individual outer bosses could be provided for each one of the fittings 44 , 46 and 48 . The apertures for the fittings 84 , 86 and 92 are each provided with their own outer boss 110 , 112 and 114 , respectively.
[0067] It is contemplated that the aperture provided for the pump mounting assembly 90 could also be provided with an outer boss formed by laying additional layers of carbon fibers impregnated with epoxy resin to the region of the aperture.
[0068] Once the outer bosses 108 , 110 , 112 , and 114 have been laid on the tank body 26 , the tank body 26 and the outer bosses 108 , 110 , 112 , and 114 are cured. Once cured, the apertures for the fittings 44 , 46 , 48 , 84 , 86 , and 92 are cut through the outer bosses 108 , 110 , 112 , and 114 , the outer shell 98 and the liner 96 . The aperture for the pump mounting assembly 90 is also cut.
[0069] Once the apertures for the fittings 44 , 46 , 48 , 84 , 86 , and 92 and for the pump mounting assembly 90 are cut, the fittings 44 , 46 , 48 , 84 , 86 , and 92 and the pump mounting assembly 90 are mounted to the tank body 26 .
[0070] Turning now to FIG. 10 , a baffle assembly 200 of the tank 12 will be described. The baffle assembly 200 is a removable structure used for decreasing liquid sloshing in the tank 12 . As will be described below, the baffle assembly 200 is adapted to be inserted though the man-way and assembled inside the tank body 26 by an operator. The baffle assembly 200 is secured to the tank body 26 by four retaining systems 300 A. The retaining systems 300 A will be described in detail below. It is contemplated that the tank 12 could have more than one baffle assembly 200 . Although the baffle assembly 200 and retaining systems 300 A for the baffle assembly are described herein for the tank 12 having a liner 96 , it is contemplated that some aspects could be used on a tank having no liner.
[0071] The baffle assembly 200 includes two baffles 210 crossing each other at their mid-length. The baffle assembly 200 forms a generally X-shape. The baffle assembly 200 is disposed inside the tank body 26 at about mid-length of the cylindrical central section 100 of the liner 96 . The baffle assembly 200 is disposed vertically on a vertical cross-sectional plane 11 (shown in FIGS. 3 and 4 ). The baffles 210 are disposed so as to leave a clearance at the bottom of the tank body 26 for liquid to drain toward the pump 88 and drain fitting 92 . It is contemplated that only one or more than two baffles 210 could be included in the baffle assembly 200 . It is also contemplated that the baffles 210 could be disposed somewhere else in the tank body 26 . It is contemplated that the baffles 210 could be disposed differently in the tank body 26 . For example the baffles 210 could be disposed vertically and not crossing each other. It is also contemplated that the baffles 210 could cross each other at locations other than their mid-length. It is contemplated that the baffles 210 could not be disposed on a vertical cross-sectional plane. It also contemplated that the two baffles 210 could be different from each other.
[0072] The baffles 210 are elongated boards that are retained at each end relative to the liner 96 by the retaining systems 300 A. It is contemplated that the baffles 210 could be retained at one end only or could be retained additionally at their sides by one or more retaining systems 300 A or by another retaining mean. It is also contemplated that the baffles 210 could have a shape different from an elongated board.
[0073] Each baffle 210 is composed of two sub-baffles 212 , each of equal width 214 (shown in FIG. 12 ) smaller than a width of the baffle 210 . The narrower sub-baffles 212 can be inserted in the man-way. In an exemplary embodiment shown in the Figures, the man-way has a diameter of 16 inches (40.64 cm), an interior of the tank body 26 has a diameter 27 of about 82 inches (208.2 cm), the sub-baffles 212 have the width 214 of about 14.5 inches (36.83 cm), a thickness of about 0.27 inch (0.68 cm), and a length 216 of 70 inches (177.8 cm) (shown in FIG. 12 ). Once assembled, the baffle 210 is of 29 inches (73.6 cm) in width and 70 inches in length (177.8 cm). Each baffle 210 is disposed at an angle 203 of 45 degrees with respect to a vertical 211 . It is also contemplated that the sub-baffles 212 could not be all identical to each other. It is contemplated that only one or more than two sub-baffles 212 could be part of each baffle 210 . It is contemplated that the dimensions of the sub-baffles 212 could be different. It is contemplated that the baffles 210 could be disposed at an angle 203 other than 45 degrees from the vertical 211 . It is also contemplated that the baffles 210 could not be disposed at a same angle 203 with respect to the vertical 211 .
[0074] The sub-baffles 212 have a flange 218 (shown in FIG. 11 ) on each side 213 (shown in FIG. 12 ) along their length 216 to form a generally squared U-shaped channel. In the exemplary embodiment shown in the Figures, the flanges 218 are each 3 inches (7.62 cm) high. The flanges 218 provide structural resistance to the sub-baffles 212 . It is contemplated that the flanges 218 could have a different height. It is also contemplated that the flanges 218 could be omitted or could be disposed only on a portion of the sides 213 of the sub-baffles 212 . The sub-baffles 212 are made of the same composite material as the outer shell 98 of the tank body 26 . It is contemplated that the sub-baffles 212 could be made of a different composite material. It is also contemplated that the sub-baffles 212 could be made of a material different from a composite. For example, the sub-baffles 212 could be made of metal, such as aluminum.
[0075] The sub-baffles 212 have four apertures 239 at each end 217 (shown in FIG. 12 ). The apertures 239 are used as removable bolted connections to the retaining system 300 A, as will be described below. In the exemplary embodiments shown in FIGS. 10 to 16 , the apertures 239 are spaced by 3.5 inches (8.89 cm) from each other. It is contemplated that the sub-baffles 212 could have more or less than four apertures 239 , and that they could have a different spacing. It is also contemplated that the apertures 239 could be slots. The sub-baffles 212 also each have two apertures 231 at about their mid-length laterally positioned toward a center of the baffle 210 . The apertures 231 are used for bolting the sub-baffles 212 to each other to form the baffle assembly 200 . It is contemplated that more or less than two apertures 231 could be used and that the apertures 231 could be positioned somewhere else on the sub-baffles 212 . It is contemplated that systems other than bolting could be used to secure the sub-baffles 212 to each other and to the retaining systems 300 A. It is contemplated that the apertures 231 could be slots.
[0076] Turning now to FIGS. 11 to 13 , a first embodiment of the retaining systems 300 A for the baffle assembly 200 will be described. The four retaining systems 300 A being identical, only one retaining system 300 A will be described. It is contemplated that more or less than four retaining systems 300 A could be used to connect the baffle assembly 200 to the tank body 26 . Although the retaining system 300 A is described for use with the baffle 210 in the tank 12 , it is contemplated that the retaining system 300 A could be used for elements other than a baffle 210 .
[0077] The retaining system 300 A comprises a baffle connector 310 A for removably connecting to the sub-baffles 210 , two elongated members 320 A receiving the baffle connector 310 A and being fixedly connected to the tank body 26 , and two tabs 330 A for preventing motion of the baffle connector 310 A with respect to the elongated members 320 A. The baffle connector 310 A, the two elongated members 320 A and the two tabs 330 A are dimensioned to be insertable through the man-way and the retaining system 300 A is adapted to be assembled inside the tank 12 .
[0078] The baffle connector 310 A is made of aluminum. It is contemplated that the baffle connector 310 A could be made of a material other than aluminum. For example, the baffle connector 310 A could be made of the same material as the elongated members 320 A. As best seen in FIG. 12 , the baffle connector 310 A has a horizontal top 311 A, a horizontal bottom 336 A, two curved portions 334 A on the ends of the horizontal bottom 336 , and two flanges 332 A extending from sides 337 A of the baffle connector 310 A. The flanges 332 A will be described below. It is contemplated that the baffle connector 310 A could not have the curved portions 334 A. The two curved portions 334 A have a curvature corresponding to a curvature of the tank body 26 . The flat bottom 336 A is spaced (see clearance 350 A in FIG. 13 ) from the liner 96 when the baffle connector 310 A is disposed between the elongated members 320 A. It is contemplated that the bottom 336 A could not be flat. It is also contemplated that the bottom 336 A could have a curvature corresponding to that part of the tank body 26 . It is also contemplated that the clearance 350 A could be omitted, and that the clearance 350 A could be filled. In the exemplary embodiment shown in FIGS. 10 to 13 , a distance from the top 311 A to the bottom 336 A is about 6 inches (15.24 cm), a thickness 313 A (shown in FIG. 13 ) of the baffle connector 310 A is 1 inch (2.54 cm), and the top 311 A of the baffle connector 310 A has a length of 29.25 inches (74.3 cm). It is contemplated that the baffle connector 310 A could have dimensions different from recited above.
[0079] The baffle connector 310 A has height apertures 339 for removably connecting to the four apertures 239 of two of the sub-baffles 212 via bolts (not shown). The apertures 339 are spaced so as to be aligned with the four apertures 239 of the sub-baffles. In the exemplary embodiment shown in FIGS. 10 to 13 , the height apertures 339 are disposed at 3.5 inches (8.89 cm) from each other, except for the two centrally disposed ones which are at 4 inches (10.16 cm) from each other. The apertures 339 are disposed at 1.25 inches (3.17 cm) from the top 311 of the baffle connector 310 A. The sub-baffles 212 are not bolted to each other but form a connection through the baffle connector 310 A. When connected to the baffle connector 310 A, the sub-baffles 212 have two of the sides 213 adjacent to each other with flanges 218 abutting each other. It is contemplated that the sub-baffles 212 could be connected directly to each other. It is contemplated that the apertures 339 could be slots. It is contemplated that the apertures 339 could be disposed at other locations on the baffle connector 310 A. It is also contemplated that the number of apertures 339 could be different. It is contemplated that the sub-baffles 212 could be bolted to each other or secured to each other additionally to being bolted to the baffle connector 310 A. It is also contemplated that the sub-baffles 212 could not be abutting each other at the flanges 218 , but could have a space between them. It is contemplated that more than one baffle connector 310 A could be used. It is contemplated that the sub-baffles 212 could be connected permanently to the baffle connector 310 A and that the retaining system 300 A could have a removable portion to remove both the baffles 210 and the baffle connector 310 A. It is also contemplated that the baffle connector 310 A could be omitted.
[0080] The flanges 332 A of the baffle connector 310 A are used for restricting motion of the baffle connector 310 A within the elongated members 320 A through abutment against the tabs 330 A, as will be described below. In an exemplary embodiment shown in FIG. 12 , the flanges 332 A extend about 1.4 inches (3.55 cm) from each side 337 A of the baffle connector 310 A. The flanges 332 A are at 3 inches (7.62 cm) vertically below the top 311 A. It is contemplated that more than one flange 332 A could be located on each side of the baffle connector 310 A. It is contemplated that the flanges 332 A could have other dimensions.
[0081] The elongated members 320 A will now be described. The elongated members 320 A are two elongated beams disposed adjacent to each other. Although the elongated members 320 A are two separate beams, it is contemplated that the elongated members 320 A could be connected to each other. For example, the elongated members 320 A could be the vertically extending flanges of a U-shaped channel. It is also contemplated that the elongated members 320 A could each be composed of several beams of lesser length or tabs disposed next to each other along their length so as to generally form a beam.
[0082] The elongated members 320 A have a height 329 A (shown in FIG. 13 ), and a thickness 325 A (shown in FIG. 13 ). The height 329 A is selected so as to allow the clearance 350 A between the bottom 336 A of the baffle connector 310 A and the liner 96 . In the exemplary embodiment shown in the Figures, the height 329 A is about 5.5 inches (13.97 cm) and the thickness 325 A is about 1 inch (2.54 cm). It is contemplated that the height 329 A and the thickness 325 A could be different from the height and thickness recited above.
[0083] The elongated members 320 A have a length 323 A (shown in FIG. 12 ) greater than the length of the baffle connector 310 A. In the exemplary embodiment shown in the Figures, the length 323 A is of 32 inches (81.3 cm). It is contemplated that the elongated members 320 A could be shorter than or have the same length as the baffle connector 310 A. It is contemplated that the elongated members 320 A could be longer than illustrated in FIG. 12 such that the same elongated members 320 A could be used to retain two different baffle connectors 310 A. For example, the elongated members 320 A could span a majority of the circumference of the liner 96 such that the baffle connectors 310 A disposed at each end of the baffle 210 could be received between the same two elongated members 320 A.
[0084] The elongated members 320 A have a curved top 326 A and a curved bottom 328 A. The curvature of the curved bottom 328 A corresponds to a curvature of the liner 96 at a location where the elongated members 320 A are connected to the liner 96 . In the exemplary embodiment shown in FIG. 12 , a radius of curvature of the top 326 A is about 38 inches (95.62 cm), and a radius of curvature of the d bottom 328 is about 41 inches (104.14 cm). It is contemplated that the top 326 A and bottom 328 could have different radii of curvature. It is contemplated that the top 326 A could be flat.
[0085] The elongated members 320 A have flat surfaces 322 A extending from each end of the top 326 A. The flat surfaces 322 A receive the tabs 330 A thereon. In the exemplary embodiment shown in the Figures, the flat surfaces 322 A have a length of about 2.5 inches (6.35 cm). It is contemplated that the flat surfaces 322 A could have a different length.
[0086] The curved bottom 328 A of the elongated members 320 A is welded by welds 327 A (schematically shown in FIG. 13 ) to the liner 96 . The clearance 350 allows for the welds 327 A not to interfere with the baffle connector 310 A. The elongated members 320 A are made of the same material as the liner 96 (HDPE), and welding is achieved by heating beads of HDPE at an interface between the liner 96 and the elongated members 320 A. The materials used for the elongated members 320 A, the baffle assembly 200 and the welds 327 A are compatible with the liner 96 and with one another in terms of thermal expansion and contraction so that the retaining system 300 A is not overly stressed because of thermal expansion and contraction. It is contemplated that the elongated members 320 A could be made of a material different from that of the liner 96 . It is also contemplated that connection of the elongated members 320 A to the liner 96 could be done differently. It is contemplated that the elongated members 320 A could be bonded to the liner 96 by an adhesive.
[0087] Turning to FIG. 13 , the elongated members 320 A are spaced from each other so as to allow the baffle connector 310 A and a shim 360 to be inserted therein. The shim 360 is used for ease of manufacturing and tolerances purposes. The shim 360 will be described below. In the exemplary embodiment shown in FIG. 13 , a distance 345 A between the two elongated members 320 A is about 1.5 inches (3.81 cm), and a thickness 314 of the shim 360 is 0.5 inch (1.27 cm). As mentioned above, the thickness 313 A of the baffle connector 310 A is 1 inch (2.54 cm). It is contemplated that the distance 345 A between the elongated members 320 A and the thicknesses 314 of the shim 360 and the baffle connector 310 A could be different. It is contemplated that more than one shim 360 could be used. It is contemplated that the shim 360 could be omitted, should the thickness of the baffle connector 310 A correspond to the distance 345 A between the elongated members 320 A.
[0088] The shim 360 is made of HDPE. It is contemplated that the shim 360 could be made of a different material. The shim 360 runs along the length 323 A of the elongated members 320 A. It is contemplated that the shim 360 could be shorter than the elongated members 320 A.
[0089] Referring back to FIG. 12 , the tabs 330 A will now be described. The tabs 330 A are generally rectangular and flat and are dimensioned to connect to each of the two adjacent elongated members 320 A. The tabs 330 A are made of the same material as the elongated members 320 A, and are welded to the elongated members 320 A. It is contemplated that the tabs 330 A could be connected to the elongated members 320 A by other means. For example, the tabs 330 A could be connected to the elongated members 320 A by an adhesive. It is also contemplated that the tabs 330 A could be removably connected to the elongated members 320 A. For example, the tabs 330 A could be bolted to the elongated members 320 A. In the exemplary embodiment shown in FIGS. 10 to 13 , the tabs 330 A have a width 331 A (shown in FIG. 12 ) of 3.5 inches (8.89 cm), a thickness of about 0.75 inch (1.9 cm), and a length 333 A (shown in FIG. 12 ) of 1.38 inches (3.5 cm). The width 331 A of the tabs 330 A corresponds to a distance between two external sides of the elongated members 320 A. The length 333 A of the tabs 330 A is smaller than the length of the flat surfaces 322 A. It is contemplated that the tabs 330 A could be smaller or longer than the flat surfaces 322 A. It is also contemplated that the tabs 330 A could have dimensions different from those recited above.
[0090] As mentioned above, it is contemplated that the baffle connector 310 A could be omitted from the retaining system 300 A, and that the baffle 210 could be directly and removably retained by the elongated members 320 A. The tabs 330 A could be removably connected to the elongated members 320 A so that, once the tabs 330 A removed, the sub-baffles 212 could be detached from the elongated members 320 A. The sub-baffles 212 could have an end free of the flange 218 so as to be snugly insertable in between the elongated members 320 A. The end without flange 218 could feature a side flange similar to the flange 332 A for providing abutment with the tabs 330 A. The two sub-baffles 212 could or could not be secure to each other. Other designs are contemplated.
[0091] Referring to FIG. 12 , assembly of the retaining system 300 A will be described. The sub-baffles 212 , the baffle connector 310 A, the tabs 330 A, the elongated members 320 A, the bolts, the shim 360 , and necessary tools are introduced through the man-way before proceeding to the assembly. It is contemplated that the above elements could be introduced as they are needed during the assembly.
[0092] First, two elongated members 320 A are disposed adjacent to each other at the distance 345 A from each other and in a location in the tank body 26 so as to be located about the vertical cross-sectional plane 11 of the tank body 26 . Once positioned, the elongated members 320 A are welded to the liner 96 . The welds 327 A are achieved by heating the beads of HDPE. The two elongated members 320 A are spaced from each other so as to allow snug insertion of the baffle connector 310 A and shim 360 .
[0093] Second, the baffle connector 310 A and the shim 360 are inserted in between the two adjacent elongated members 320 A. The baffle connector 310 A is positioned so that the side flanges 332 A are generally levelled with the flat surfaces 322 A of the two adjacent elongated members 320 A. The shim 360 is positioned to be generally levelled with the flat surfaces 322 A of the two adjacent elongated members 320 A. It is contemplated that the baffle connector 310 A and the shim 360 could not be levelled with the elongated members 320 A, as long as the shim 360 and the side flanges 332 A are disposed within the elongated members 320 A. The baffle connector 310 A is held by friction-fit between the elongated members 320 A. The elongated members 320 A restrain motion in a longitudinal direction (illustrated by arrows 420 in FIG. 11 ). It is contemplated that one or both of the adjacent elongated members 320 A could be welded to the liner 96 after positioning the baffle connector 310 A and shim 360 .
[0094] Third, once the baffle connector 310 A and the shim 360 are positioned within the elongated members 320 A, the tabs 330 A are welded to the flat surfaces 322 A. The tabs 330 A prevent the baffle connector 310 A to move in circumferential and radial directions (illustrated by arrows 400 and 410 respectively in FIG. 10 ). Once the tabs 330 A are welded to the elongated members 320 A, the baffle connector 310 A is securely retained to the liner 96 .
[0095] The above operation is repeated for the three other retaining systems 300 A. Each retaining systems 300 A is positioned so that the baffles 210 can be disposed in the X shape (shown in FIG. 10 ) on the vertical cross-sectional plane 11 . To achieve this, two of the retaining systems 300 A may be offset from the vertical plane 11 by a distance corresponding to the thickness of the baffles 210 in order to allow the baffles 210 to cross-each other. It is contemplated that one could start with assembling only two of the retaining systems 300 A so as to secure one baffle 210 across the tank body 26 , before proceeding with two other retaining systems 300 A so as to secure the other baffle 210 across the tank body 26 .
[0096] To assemble one of the baffles 210 , two sub-baffles 212 are disposed next to each other and bolted at their ends 217 to two opposite baffle connectors 310 A. The two sub-baffles 212 are disposed so that the flanges 218 extend toward a same direction, but each baffle 210 is disposed so that the flanges 218 are facing away from each other. Once in position, the apertures 231 of the four sub-baffles 212 are aligned with each other, and the sub-baffles 212 are bolted to each other via the apertures 231 .
[0097] When desired, the operator can unbolt the sub-baffles 212 from each other and from the baffle connector 310 A, leaving the retaining systems 300 A connected to the tank body 26 .
[0098] Turning now to FIG. 14 , a second embodiment of a retaining system 300 B for the baffle assembly 200 will be described.
[0099] The retaining system 300 B comprises a baffle connector 310 B, two elongated members 320 B, two caps 330 B, and the shim 360 . The baffle connector 310 B, the two elongated members 320 B and the two caps 330 B are dimensioned to be insertable through the man-way and the retaining system 300 B is adapted to be assembled inside the tank 12 , as will be described below. It is contemplated that the shim 360 could be omitted.
[0100] The baffle connector 310 B is similar to the baffle connector 310 A except that it does not have the side flanges 332 A and the curved portions 334 A. It is contemplated that the baffle connector 310 B could have side flanges and/or curved portions. Common elements between the baffle connectors 310 B and 310 A will not be described again.
[0101] The elongated members 320 B are similar to the elongated members 320 A except that their tops 326 B is flat. It is contemplated that the elongated members 320 B could have their tops 326 B curved. Common elements between the elongated members 320 A and 320 B will not be described again.
[0102] The caps 330 B are similar to the tabs 330 A except that they are dimensioned to cover ends 321 B of the elongated members 320 B instead of tops of the elongated members 320 B. The caps 330 B are dimensioned to have a height 331 B corresponding to about a height of the elongated members 320 B and width 333 B corresponding to a distance between two external sides of the elongated members 320 B. The caps 330 B have a flat bottom 335 B. The caps 330 B prevent the baffle connector 310 B to move in the circumferential direction, and the friction-fit provided by the elongated members 320 B restrain the baffle connector 310 B from moving in the radial direction. It is contemplated that the baffle connector 310 B could have, in addition, flanges to abut against tabs similar to the tabs 330 A, to further prevent motion of the baffle connector 310 B in the radial direction. It is also contemplated that the caps 330 B could have other dimensions. It is contemplated that the bottom 335 B could be curved.
[0103] It is contemplated that the baffle connector 310 B could be omitted from the retaining system 300 B and that the baffle 210 could be directly and removably retained by the elongated members 320 B. The caps 330 B could be removably connected to the elongated members 320 B so that, once the caps 330 B removed, the sub-baffles 212 could be rotated so as to be removed from the elongated members 320 B. The sub-baffles 212 could have an end free of flange 218 so as to be snugly insertable in between the elongated members 320 B. The ends without flange 218 could feature a side flange similar to the flange 332 A for providing abutment with the caps 330 B. The two sub-baffles 212 could or could not be secured to each other. Other designs are contemplated.
[0104] The retaining system 300 B is assembled in a way similar to the retaining system 300 A and will not be described in details herein again. The elongated members 320 B are welded to the liner 96 , the baffle connector 310 B and the shim 360 are inserted in between the elongated members 320 B, the caps 330 B are welded to the ends 321 B of the elongated members 320 B and the sub-baffles 212 are bolted to the baffle connector 310 B.
[0105] Turning now to FIG. 15 , a third embodiment of a retaining system 300 C for the baffle assembly 200 will be described.
[0106] The retaining system 300 C comprises a baffle connector 310 C, two elongated members 320 C, four tabs 330 C, and the shim 360 . The elongated members 320 C are similar to the elongated members 320 B and will not be described herein again. The baffle connector 310 C, the two elongated members 320 C and the tabs 330 C are dimensioned to be insertable through the man-way and the retaining system 300 C is adapted to be assembled inside the tank body 26 , as will be described below. It is contemplated that the shim 360 could be omitted.
[0107] The baffle connector 310 C is similar to the baffle connector 310 A except that it has four rectangular apertures 338 C defined therein and has no side flanges. Elements common to the baffle connectors 310 A and 310 C will not be described again. It is contemplated that more or less than four apertures 338 C could be provided, and that the apertures 338 C could not be rectangular. The apertures 338 C are disposed vertically below the apertures 339 so that once in place, the apertures 339 are accessible for bolting the baffle connector 310 C to the sub-baffles 212 .
[0108] The tabs 330 C are used to retain the baffle connector 310 C between the elongated members 320 C. The tabs 330 C are adapted to be inserted into the apertures 338 C and welded to a top 326 C of the elongated members 320 C. It is contemplated that the tabs 330 C could be removably connected to the elongated members 320 C. The tabs 330 C prevent motion of the baffle connector 310 C in both the radial and the circumferential directions.
[0109] It is contemplated that the baffle connector 310 C could be omitted from the retaining system 300 C and that the baffle 210 could be directly and removably connected to the elongated members 320 C by providing the apertures 239 in the sub-baffles 212 . The tabs 330 C could be removably connected to the elongated members 320 C so that, once the tabs 330 C removed, the sub-baffles 212 could be detached from the elongated members 320 C. The sub-baffles 212 could have an end free of flange 218 so as to be snugly insertable in between the elongated members 320 C. The two sub-baffles 212 could or could not be secured to each other. Other designs are contemplated.
[0110] The retaining system 300 C is assembled in a way similar to the retaining system 300 A, and will not be described in details herein again. The elongated members 320 C are welded to the liner 96 , the baffle connector 310 C and the shim 360 are inserted in between the elongated members 320 C with apertures 239 extending right above the top of the elongated members 320 C. The tabs 330 C are inserted into the apertures 239 and have their ends welded to the tops 326 C of the elongated members 320 C.
[0111] Turning now to FIG. 16 , a fourth embodiment of a retaining system 300 D for the baffle assembly 200 will be described.
[0112] The retaining system 300 D comprises a baffle connector 310 D, two elongated members 320 D, two caps 330 D, and the shim 360 . The caps 330 D are similar to the caps 330 B and will not be described herein again. The baffle connector 310 D, the two elongated members 320 D and the two caps 330 D are dimensioned to be insertable through the man-way and the retaining system 300 D is adapted to be assembled inside the tank body 26 , as will be described below. It is contemplated that the shim 360 could be omitted.
[0113] The baffle connector 310 D is similar to the baffle connector 310 B except that it has two flanges 332 D extending outwardly. The flanges 332 D are dimensioned to abut against flanges 355 D of the elongated members 320 D.
[0114] The elongated members 320 D are similar to the elongated members 320 B except that they each have one flange 355 D located at a top of the elongated members 320 D. The elongated members 320 D are to be disposed facing each other so that the flanges 335 D create a rail therebetween. The flanges 335 D prevent the baffle connector 310 D from moving in the radial and longitudinal directions. The caps 330 D prevent the baffle connector 310 D to move in the circumferential direction by sliding out of the rail. It is contemplated that each flange 335 D could comprise two flanges vertically aligned so as to brace one of the flange 332 D of the baffle connector 310 D.
[0115] It is contemplated that the baffle connector 310 D could be omitted from the retaining system 300 D and that the baffles 210 could be directly and removably retained by the elongated members 320 D. The caps 330 D could be removably connected to the elongated members 320 D. To allow a secure connection between the sub-baffles 212 and the elongated members 320 D, the sub-baffles 212 could be modified to have an end free of flange 218 . The baffle connector 310 D could be omitted and the sub-baffles 212 could have flanges similar to flanges 332 A to be retained by the elongated members 320 D so that, once the caps 330 D removed, the sub-baffles 212 could be slid in and out the elongated members 320 D. The two sub-baffles 212 could or could not be secured to each other. Other designs are contemplated.
[0116] The retaining system 300 D is assembled in a way similar to the retaining system 300 A, and will not be described again in details herein again. The elongated members 320 D are welded to the liner 96 with flanges 335 D facing each other and spaced so as to allow the baffle connector 310 D to be received therebetween. The baffle connector 310 D and the shim 360 are inserted in between the elongated members 320 D. The baffle connector 310 D is inserted from a side of the elongated members 320 A (as illustrated in FIG. 16 ) so as to insert the flanges 332 D vertically below the flanges 335 D. The shim 360 is disposed between a side of the flanges 332 D and the elongated members 320 D. It is contemplated that the shim 360 could be disposed somewhere else. For example, the shim 360 could be disposed between the flanges 332 D and 355 D. The caps 330 D are welded or fastened to the sides of the elongated members 320 D, once the baffle connector 310 D is disposed inside the elongated members 320 D.
[0117] Turning now to FIGS. 17 and 18 , a fifth embodiment of a retaining system 300 E for a second embodiment of the baffle assembly 200 E will be described. The retaining system 300 E is described for retaining a pair of sub-baffles 212 E. The sub-baffles 212 E are similar to the sub-baffles 212 except that they each have two apertures 239 E each instead of four. Each aperture 239 E is a slot. The slot is about 1 inch (2.54 cm) long. The apertures 239 E of a same sub-baffle 212 E are spaced from each other by 9.5 inches (24.13 cm). The sub-baffles 212 E also each have two apertures 231 E which are similar to the apertures 231 of the sub baffle 212 except that they are slots. It is contemplated that the sub-baffles 212 E could have more or less than two apertures 239 E each. It is also contemplated that the apertures 239 E could be at a distance from each other different from the one recited above.
[0118] The retaining system 300 E comprises a baffle connector 310 E, two elongated members 320 E, two caps 330 E, and a wear element 361 . The baffle connector 310 E, the two elongated members 320 E and the two caps 330 E are dimensioned to be insertable through the man-way and the retaining system 300 E is adapted to be assembled inside the tank 12 , as will be described below. It is contemplated that the wear element 361 could be omitted.
[0119] The baffle connector 310 E is similar to the baffle connector 310 A, and common elements between the baffle connectors 310 E and 310 A will not be described again. The baffle connector 310 E has four apertures 339 E to connect with the four apertures 239 E of the sub-baffles 212 E, and has two apertures 340 E, one on each flange 332 E. The apertures 339 E, 340 E are slots. The baffle connector 310 E has a flat portion 334 E. It is contemplated that the baffle connector 310 E could have more or less than four apertures 339 E and/or two apertures 340 E. It is also contemplated that the apertures 339 E and/or 340 E could not be slots. It is contemplated that the apertures 340 E could be omitted. It is contemplated that the portion 334 E could be curved.
[0120] The elongated members 320 E are similar to the elongated members 320 A except that they each have two apertures 341 E and two apertures 342 E. Common elements between the elongated members 320 A and 320 E will not be described again. As will be described below, the wear element 361 is bolted between the elongated members 320 E via the apertures 341 E and to the baffle connector 310 E via apertures 342 E. It is also contemplated that the elongated members 320 E could have none, more than one or two apertures 341 E.
[0121] The caps 330 E are U-shaped to cover a top and parts of external sides of the elongated members 320 E. The caps 330 E have each two apertures 343 E (only one being shown on each cap 330 E) for receiving bolts (not shown) to secure the caps 330 E to the elongated members 320 E via the apertures 342 E. The caps 330 E are dimensioned to provide a snug fit with the elongated members 320 E. In the exemplary embodiment shown in FIG. 17 , a height 333 E of the caps 330 E is 2.5 inches (6.35 cm) and a length 331 E of the caps 330 E is of 4 inches (10.16 cm). The caps 330 E are each disposed at 0.25 inch (0.63 cm) from a corresponding one of the ends 322 E of the elongated members 320 E. The caps 330 E prevent the baffle connector 310 E to move in the radial direction, and the friction-fit provided by the elongated members 320 E restrain the baffle connector 310 E from moving in the radial and circumferential directions. It is contemplated that the retaining system 300 E could further have tabs similar to the caps 330 B, to further prevent motion of the baffle connector 310 E in the circumferential direction. It is contemplated that the caps 330 E could be disposed more or less close to the ends 322 E. It is also contemplated that the caps 330 E could have more or less than two apertures 343 E each. For example, the caps 330 E could have no aperture 343 E, and could be welded to the elongated members 320 E during assembly of the retaining system 300 E. It is contemplated that the baffle connector 310 E could be omitted from the retaining system 300 E and that the sub-baffle 212 E could be directly and removably retained by the elongated members 320 E. Once the caps 330 E removed, the sub-baffles 212 E could be rotated so as to be removed from the elongated members 320 E. The sub-baffles 212 E could have an end free of flange 218 so as to be snugly insertable in between the elongated members 320 E. The ends without flanges 218 could each have side flanges similar to the flanges 332 A for providing abutment with the caps 330 E. The two sub-baffles 212 E could or could not be secured to each other. Other designs are contemplated.
[0122] The wear element 361 is adapted to be disposed between the elongated members 320 E. The wear element 361 has two apertures 367 for receiving bolts (not shown) to secure the wear element 361 to the elongated members 320 E. It is contemplated that the wear element 361 could have only one or more than two apertures 367 . The wear element 361 is bolted to the elongated members 320 E to present the liner 96 from being worn by movements of the wear element 361 during use of the transport tank 12 . It is contemplated that the wear element 361 could be secured to the elongated members 320 E by ways other than bolting. For example, the wear element 361 could be held by friction fit to the elongated members 320 E. The wear element 361 has a curved bottom 363 congruent with the liner 96 . The wear element 361 is made of a material similar to the one of the liner 96 . It is contemplated that the wear element 361 could be made of a material different from the one of the liner 96 . The wear element 361 has a shorter length 365 and a shorter height 362 than the ones of the elongated members 320 E, but has a thickness 364 corresponding to a distance 345 E between the elongated members 320 E. In the exemplary embodiment shown in FIGS. 17 and 18 , the length 365 of the wear element 361 is 23 inches (58.42 cm), the thickness 364 (shown in FIG. 18 ) of the wear element 361 is 1 inch (2.54 cm), and the height 362 of the wear element 361 is 1.63 inches (4.14 cm), smaller than a height 329 E (shown in FIG. 18 ) of the elongated members 320 E to allow the baffle connector 310 E to be inserted between the elongated members 320 E. It is contemplated that the wear element 361 could have dimension different from the ones recited above.
[0123] The retaining system 300 E is assembled in a way similar to the retaining system 300 A and will not be described in details herein again. The elongated members 320 E are welded to the liner 96 by welds 327 E (shown in FIG. 18 ). The welds 327 E are similar to the welds 327 A. The wear element 361 is inserted between the elongated members 320 E. The apertures 367 of the wear element 361 are aligned with the apertures 341 E of the elongated members 320 E. The wear element 361 is welded to the liner 96 . It is contemplated that the wear element 361 could not be welded to the liner 96 . Bolts are slid into the apertures 341 E, 367 and are secured by nuts (not shown) so that the wear element 361 is secured to the elongated members 320 E. The baffle connector 310 E is inserted between the elongated members 320 E to rest onto the wear element 361 . The caps 330 E are disposed at the ends 322 E of the elongated members 320 E. For each side of the elongated members 320 E, a bolt is inserted through the apertures 343 E of the caps 330 E, the apertures 342 E of the elongated members and the apertures 340 E of the baffle connector 310 E so as to secure the baffle connector 310 E with the elongated members 320 E and the caps 330 E. The caps 330 E are welded to the elongated members 320 E. It is contemplated that the caps 330 E could not be welded to the elongated members 320 E. The sub-baffles 212 are bolted to the baffle connector 310 E, in a way similar to what has been described above for the retaining system 300 A.
[0124] 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. | A lined transport tank for mounting to a truck is provided. The tank has a lined tank body. The tank body has an inner surface. A baffle is removably connected to the inner surface of the tank body. A retaining system is removably connecting the baffle to the inner surface of the tank body. The retaining system has a pair of elongated members fixedly connected to the inner surface of the tank body. The pair of elongated members is restraining movement of the baffle in a first direction. A retainer is connected to the pair of elongated members. The retainer is restraining movement of the baffle in a second direction. The second direction is different from the first direction. A retaining system for removably connecting an element to a surface is also provided. | 8 |
This is an con of Ser. No. 07/764,706 Sept. 24, 1991 U.S. Pat. No. 5,301,326.
TECHNICAL FIELD
This invention relates generally to methods for controlling the execution of an application program, and more specifically a method and system for providing a user interface for controlling the performing of specialized tasks by the application program.
BACKGROUND OF THE INVENTION
There currently exists a plethora of general-purpose application computer programs. These general-purpose application programs include word processors, desk top publishers, spreadsheets, and data base products. The field is very competitive for producing these products. When these general-purpose application programs were first developed for personal computers, they were unsophisticated by today's standards. Due in part to competitive pressures, these programs evolved into very sophisticated programs that provide many features and options. For example, the original spreadsheet products basically provide a grid of cells for numerical calculations. Spreadsheet products today provide many more capabilities such as graphing data, storing and retrieving data, and programming functions.
Unfortunately, as these general-purpose application programs get more sophisticated, the user also needs to be more sophisticated to take advantage of advanced features. These advanced features often make tasks that were previously simple more complicated to perform. Consequently, users must devote a considerable amount of time to learning the product to perform these previously simple tasks. This complexity also affects the efficiency of tasks that are performed for the first time on an infrequent basis. For example, a user may want to quickly produce a quarterly newsletter using a desktop publishing product, but the user may not have design skills or skills in using all the necessary parts of the application. Also, a user may produce a quarterly newsletter using a desktop publishing product. However, the user may forget how to use many of the features of the publisher in between issues of the newsletter. Thus, the user must spend a certain amount of re-learning time each quarter.
A feature that has recently been added to several general-purpose computer programs is interprocess communications. Interprocess communications allows computer programs to transmit data to each other through communications channels. Interprocess communications has typically been used to synchronize programs, to request data from a program, and send data to a program. Microsoft Corporation has developed a standard interprocess communications mechanism for application programs. The mechanism is called the Dynamic Data Exchange (DDE). The DDE provides a means for interprocess communications for programs that are developed for the Windows windowing environment. The DDE feature of Windows is described in the “Microsoft Systems Journal,” November, 1987 and the “Microsoft Windows Programmer's Reference.” The DDE is implemented through message passing. The DDE is typically used to allow two application programs to share data. For example, a user may want to incorporate a quarterly chart that is developed in a graphics package into a newsletter. Using DDE, the publisher product could request a new chart to be generated by the graphics product. The publisher product could then automatically incorporate the new chart into the current newsletter. The DDE thus provides a mechanism for one program to share and update data with another program.
Typically, developers of application programs that use the DDE will publish their DDE interface. For example, the developer of a spreadsheet product will publish a list of messages that it will recognize and how it will respond to those messages. Some general-purpose application programs define these messages so that each function that can be accomplished through the user interface to the application program can be accomplished through the DDE.
It would be desirable to have an easy-to-use method and system for using theses sophisticated general-purpose programs.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method and system for performing a specialized task in a general-purpose application program.
It is another object of the present invention to provide a new user interface to a preexisting application program to control the execution of a task.
It is another object of the present invention to provide a method and system that allows third parties to extend and customize the features of an existing application program.
It is another object of the present invention to provide an interface program that has expert knowledge relating to the performance of a specialized task.
It is another object of the present invention to provide a system architecture for the performing of specialized task in an application program.
These and other objects, which will become apparent as the invention is more fully described below, are obtained by a method and system for controlling the execution of an application program to effect the performing of a specialized task. In preferred embodiments, an interface computer program gathers status information from the application computer program, collects user input relating to the specialized task, generates commands to send to the application program, and sends the commands to the application program to effect the execution of the specialized task.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a block diagram of an application program and an interface program.
FIG. 1B illustrates a user interface program that interacts with two application programs.
FIG. 2 is a flow diagram of typical communication sequence between an interface program and an application program
FIG. 3 shows a display for the Calendar PageWizard.
FIG. 4 is a flow diagram of the main window procedure for a PageWizards.
FIGS. 5A, 5 B, and 5 C are flow diagrams of the message processing procedure for the PageWizard main window.
FIG. 6 is a flow diagram of the procedure GoPage.
FIGS. 7A, 7 B, and 7 C are a flow diagrams of a preferred window procedure for a page.
FIG. 8 is a flow diagram of the AskPublisher procedure.
FIG. 9 is a flow diagram of the TellPublisher procedure.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides methods for implementing a user interface to one or more application programs. According to the methods, an interface program interacts with an application program and a user to effect the performance of a desired task. An interface program is referred to as a wizard. For example, in one embodiment of the present invention, several user interface programs, called PageWizards, provide new user interfaces to a desktop publishing application program, called Publisher. Each PageWizard provides a user interface to perform a specific task with the Publisher. One such PageWizard, called Calendar PageWizard, supports creating calendars. The Calendar PageWizard collects formatting and date information from the user. The Calendar PageWizard interacts with the Publisher to effect the creation of a calender by Publisher.
FIG. 1A is a typical block diagram of an application program 102 and an interface program 101 . The programs communicate through interprocess communications channel 105 . In a preferred embodiment, interprocess communications channel is the Dynamic Data Exchange (DDE) of Windows. However, other methods of interprocess communications are acceptable. The interface program 101 comprises a user interface portion 104 and an application interface portion 103 . The user interface portion 104 provides the user with a task-specific interface. In the example of Calendar PageWizard, the tasks is to use the Publisher to create calendars. The user interface displays calendar information to the user and collects formatting data from the user. The application interface, portion 103 prepares commands to send to the application program 102 and controls communications with the application program 102 . Alternatively, an interface program may interact with-several application programs to effect a specific task. For example, a user interface program may support a mail merge. Such a user Interface program could interact with a data base application program and a word processing application program. The mail merge interface program would collect names and addresses from the data base product based on user-entered criteria and send the data to a word processing program to merge with a user-entered document. FIG. 1B illustrates a user interface program that interacts with two application programs. The interface program 111 has a user interface portion 114 and two application interface portions 115 , 116 . Each application interface portion interfaces with one of the application programs 112 , 113 through one of the interprocess communications channels 117 , 118 .
FIG. 2 is a flow diagram of typical communication sequence between an interface program and an application program. The blocks in the right column 210 represent processing that is performed by the application program. The blocks in the left column 220 represent processing that is performed by the interface program. Initially, the application program is started. The user of the application program selects to start the interface program. In block 211 , the application programs starts the selected interface program. In other embodiments, the user could start an interface program which would then start the application program or both the application program and the interface program could be started independently of each other. In block 221 , the interface program creates status commands. These status commands request the application program to send status information to the interface program. In block 222 , the interface program sends the status commands to the application program. In block 212 , the application program processes the status commands. In block 213 , the application 25 program sends the status to the interface program. In block 223 , the interface program inputs data from the user describing the task to be performed. In block 224 , the interface program creates task commands to perform the desired task. In block 225 , the interface program sends 30 the task commands to the application program. In block 214 , the application program executes the task commands.
In a preferred embodiment, the application program and interface program operate in the Windows windowing environment. The interface program provides 35 windows through which to display information to the user and receive information from the user. FIG. 3 shows a display for the Calendar PageWizard, which interfaces with the Publisher application program. PageWizards interface with the user through a series of “pages.” The user “navigates” through these pages to input and view data. Window 301 is the main Publisher window. Window 302 is the main PageWizard window, which overlays window 301 . Window 302 comprises page-specific controls 303 , a graphic item 304 , and main navigation controls 305 . The main navigation controls 305 allow the user to select the various pages that the Calendar PageWizard provides. The “Next >” control 306 indicates to go to the next page. The “<” control 307 indicates to go to the previous page. The “|<<” control 308 indicates to go to the first page. The “Cancel” control 309 indicates to exit the Calendar PageWizard and return to the Publisher.
The pages are defined in a page resource file with user-defined resources. For each page, the resource file contains the following information:
PAGEn
PAGE
BEGIN NextPageNum, cControls,
control information,
control information,
. . .
control information,
END
where n in PAGEn specifies the page number, NextPageNum specifies the page to be displayed when the next page is selected, and cControls is the count of the control information lines that follow. The format of the control information lines is
controltype, text, id, x, y, width, height, nextpage
where the format is same as the standard dialog controls except for the item nextpage. The item nextpage specifies the next page to go to when the control is selected. This allows the navigation sequence of the pages to vary based on the control the user selects.
The graphics for the pages are defined in a resource file with user-defined resource items. There are two types of graphic items: a metafile and a text object. Each graphic item has an entry in the graphics resource file. The format for the metafile entry is
GRNAME
METAFILE
grname.wmf
GRNAME
BOUNDS
BEGIN
x, y, width, height
END
where grname.wmf specifies the name of the associated metafile (each metafile is stored in a separate file) and variables x, y, width, and height specify the positioning of the metafile on the page. The format for a text object entry is
TXNAME
TEXTOBJECT
BEGIN
stringID, x, y, width, height,
fontname, ptsize., fontstyle,
R 1 , G 1 , B 1 , R 2 , G 2 , B 2 ,
fBorder, leftindent, rightident, align
END
where stringID contains the id of a string that is stored in a string resource file. The string resource file contains stringID and the associated text string. The other variables define the position and display characteristics of the string.
In a preferred embodiment, all wizards that interact with a certain application program share common architectural features. For example, all wizards that interface with the Publisher use pages as described above. A PageWizard has a main window procedure and a window procedure for each page. The main window procedure sends messages to the pages to control the navigation through the pages. FIG. 4 is a flow diagram of the main window procedure for a PageWizards. In block 401 , the procedure opens the communications channel with the application program. In another embodiment, the communications channel is opened just before the first communications data is sent. In block 402 , the procedure initializes an internal data structure with display information from the resource files. In block 403 , the procedure requests and receives status information from the application program. In block 404 , the procedure creates the main window. In blocks 405 and 406 , the procedure executes the main message loop. The procedure waits for a message and then dispatches the message.
FIGS. 5A, 5 B, and 5 C are flow diagrams of the main window procedure for the PageWizard. This procedure displays the main window, processes the termination character, controls the navigation through the pages, and handles other miscellaneous windowing functions. Blocks 510 , 520 , 530 , 540 , 550 , and 560 decode the message. In block 510 , if the message is a WM_CREATE, then the procedure displays the main window in block 511 through 513 . In block 511 , the procedure adjusts the system menu by removing non-applicable menu commands and adding an “Abort . . . ” menu command. In block 512 , the system determines the appropriate font based on the video configuration, and then scales the size of the main PageWizard window based on the size of this font. In block 513 , the procedure displays the main window and returns. In block 520 , if the message is WM_CHAR, then the procedure continues at block 521 . In block 521 , if the WM_CHAR message indicates that the escape key was pressed, then the procedure effects the exiting of the PageWizard. In block 530 , if the message is a WM_COMMAND, a WM_ENTERPAGE, or a WM_LEAVEPAGE message, then the procedure continues at block 531 . In block 531 , if the message is for a main navigation control, then the procedure continues at block 535 , else the procedure continues at block 532 . In block 532 , the procedure passes the message to the window procedure for the page currently displayed. Each page has a corresponding window procedure to handle the messages for that page. In block 533 , the procedure updates a variable to track the current page. In block 534 , the procedure enables or disables the navigation controls to reflect whether there is no next page or no previous page and returns. In block 535 , the procedure calls procedure GoPage (described below), which effects the switching of pages and returns. In block 540 , if the message is WM_PAINT, then the procedure continues at block 541 . In block 541 , the procedure paints the main Pagewizard window and returns. In block 550 , if the message is WM_CLOSE, then the procedure continues at block 551 . In block 551 , the procedure exits the PageWizard. In block 560 , if the message is WM_SYSCOMMAND, then the procedure continues at block 561 . In block 561 , the procedure displays the about dialog box and returns.
FIG. 6 is a flow diagram of the procedure GoPage. This procedure receives a-page number and effects the changing from the current page to the received page. In block 601 , if the received page number is valid, then the procedure continues at block 602 , else the procedure returns. A page number is valid if it is defined in the page resource file. In block 602 , the procedure sends a WM_LEAVEPAGE message to the previous page. In block 603 , the procedure saves the previous page in a list of previous pages. This list is used to navigate through previous pages. In block 604 , the procedure destroys the controls of the previous page. In block 605 , the procedure creates the controls for the new page. In block 606 , the procedure sends a WM_ENTERPAGE message to the window procedure for the new page.
FIGS. 7A, 7 B, and 7 C are flow diagrams of a preferred window procedure for a page. In a preferred embodiment, the page windows are architecturally similar in the way they handle navigation controls. In block 710 , if the message is WM_ENTERPAGE, then the procedure continues at block 711 . The WM_ENTERPAGE message is sent from the procedure GoPage. In block 711 , the procedure draws the graphics objects for the page. In block 712 , the procedure initializes the controls. In block 713 , the procedure perform page-specific initialization and returns. In block 720 , if the message is WM_COMMAND, then the procedure continues at block 721 . The WM_COMMAND message is sent from the procedure GoPage. In block 721 , the procedure updates page-specific controls. In block 722 , the procedure updates page-specific graphics. In block 723 , the procedure performs page-specific processing and return. In block 730 , if the message is WM_LEAVEPAGE, then the procedure continues at block 731 . The WM_LEAVEPAGE message is sent by the procedure GoPage. In block 731 , the procedure validates the user-entered page data. In block 732 , the procedure removes page-specific graphics from the display. In block 733 , the procedure performs page-specific processing and returns.
In a preferred embodiment, the application interface portion of the interface program controls the gathering of status information from the application program, the creating of task commands, and the sending of the task commands to the application program. The application interface code creates the task commands based on the user-entered information and status information supplied by the application program. For Calendar PageWizards, the application interface generates task commands to create a calendar in the Publisher based on the user data and designs built into Calendar PageWizards. The user data specifies size, font, date, arrangement, and other options for calendar creation.
In a preferred embodiment, the application interface communicates with the application program through the dynamic data exchange (DDE) facilities of Windows. The interface program functions as a DDE client to the application program, which functions as a DDE server. The interface program initiates a conversation with the application program by sending a DDE_INITIATE message specifying the application and topic. The application program responds with a DDE_ACK message. To request status information, the interface program sends a DDE_REQUEST message with the item to the application program. The application program responds with a DDE_DATA message with the requested item. The interface program sends a request for each item it needs from the application program. The interface program sends commands to the application program by sending a DDE_EXECUTE message with the command to the application. The application program returns a DDE_ACK message when it completes processing the command. If the interface program interacts with multiple application programs, then this communications occurs with each application program.
FIGS. 8 and 9 show flow diagrams of procedures that support the DDE communications in PageWizards. FIG. 8 is a flow diagram of the AskPublisher procedure. The AskPublisher procedure opens the DDE channel if not already open and requests status information from the Publisher. This procedure receives as input parameter the item to request from the Publisher. In block 801 , if the DDE channel is not open, then the procedure opens the channel in block 802 (as described above) and continues at block 803 . In block 803 , the procedure sends a DDE_REQUEST message with the item to the Publisher. In block 804 , the procedure waits for a DDE_DATA or DDE_ACK message to be received from the Publisher. This waiting ensures that Publisher will process the request before AskPublisher returns to the invoking routine. In block 805 , if the DDE_ACK message indicates an error, then the procedure reports the status to the user in block 806 . The procedure then returns.
FIG. 9 is a flow diagram of the TellPublisher procedure. The TellPublisher procedure opens the DDE channel if not already open and send commands to execute to the Publisher. This procedure receives as input parameter the command to send to the Publisher. In block 901 , if the DDE channel is not open, then the procedure opens the channel in block 902 (as described above) and continues at block 903 . In block 903 , the procedure sends a DDE_EXECUTE message with the item to the Publisher. In block 904 , the procedure waits for the DDE_ACK message to be received from the Publisher. This waiting ensures that Publisher will process the command before TellPublisher returns. In block 905 , if the DDE_ACK message indicates an error, then the procedure reports the status to the user in block 906 and returns.
Although the methods and systems of the present invention have been disclosed and described with respect to preferred embodiment, it is not intended that the present invention be limited to such embodiments. Rather, the present invention is intended to include all legally equivalent embodiments. Modifications within the spirit of the invention will be apparent to those skilled in the art. The scope of the present invention is defined by the claims that follow. | A method and system for controlling the execution of an application program to effect the performing of a specialized task is provided. In preferred embodiments, an interface computer program gathers status information from the application computer program, collects user input relating to the specialized task, generates commands to send to the application program, and sends the commands to the application program to effect the execution of the specialized task. The interface computer program communicates with the application computer program preferably through the dynamic data exchange of Windows. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to commercial display refrigerators having glass doors for allowing viewing of merchandise contained within the refrigerator. More particularly, this invention relates to fluorescent lights that are employed within commercial display refrigerators for illuminating the merchandise contained therein.
[0003] 2. Description of the Background Art
[0004] Presently, display refrigerators are commonly used in retail stores such as grocery and convenience stores for refrigerating merchandise such as beverages behind glass doors allowing the discriminating shopper to view the merchandise while shopping. Once the selection is made, the shopper may then open the glass door and remove the product from the refrigerator.
[0005] In order to maximize the shopper's viewing convenience while minimizing the tendency of the shopper to open the glass doors during the selection process, it has been desirable to fully illuminate the merchandise located within the refrigerated display. In this manner, the shopper will hopefully not stand with the display door open while making the selection. Rather, the shopper will mentally make the selection with the door closed and then open it to withdraw the selection. In this way, heat loss to the interior as well as potential fogging of the doors, is minimized. Hence, there has been a desire in the industry for illumination systems that fully illuminate the merchandise contained within the display refrigerator without obstructing the view thereof.
[0006] Presently, there exist various configurations of lighting systems for display refrigerators in which the fluorescent lamp fixture is positioned horizontally at the top or bottom of the merchandise shelving area. More recently, lighting systems have been positioned behind the end frames that support the respective glass doors and the mullions therebetween. By positioning the lighting system behind the end frames and mullions, they are generally concealed from view by the shopping consumer and therefore do not otherwise hinder the presentation of the merchandise to the consumer.
[0007] Moreover, various lens systems, covers and reflectors have been developed for directing the light rays from the fluorescent light in a direction toward the leading edge of the display shelves so that even the merchandise in the center of the shelf midway between the end frames and mullions is fully illuminated. Such lenses and reflectors have also been designed so as to minimize the reflection of light toward the glass doors themselves that would otherwise create a distracting glare on the glass doors (i.e., a “zebra” effect) and thereby not present as pleasing of a shopping environment for the consumer.
[0008] U.S. Pat. Nos. 5,016,146 and 5,471,372 the disclosures of which are hereby incorporated by reference herein, illustrate various types of mullion-mounted lighting systems for display refrigerators.
[0009] The various configurations of lenses and reflectors employed in mullion-mounted lighting systems have achieved wide acceptance in the industry. Unfortunately, the specific designs for such lighting systems vary from manufacturer to manufacturer. Moreover, the design of such lens covers typically requires that the lens be removed in its entirety in order to change the fluorescent lamp contained therein.
[0010] The fluorescent lamp lens assembly of commonly-owned U.S. Pat. No. 6,179,443, the disclosure of which is hereby incorporated by reference herein, presented a marked improvement to the aforementioned lens assemblies by affixing a universal lighting system to the rear inside of the end frames and mullions to illuminate the leading edge of the shelving while minimizing door glare. More particularly, as shown in FIGS. 1 and 2 , the fluorescent lens assembly was generally tubular in configuration and included a length generally approximating the length of the fluorescent lamp. The fluorescent lamp was positioned into the lens assembly and held in concentric relation therein by means of a pair of end caps securing the fluorescent lamp within the tubular lens. Both of the caps allowed the terminal pins of the fluorescent lamp to extend outwardly allowing the pins to connect to the lamppost of a conventional fluorescent lamp fixture. One of the ends (e.g., the top end) was provided with a removable cap allowing a spent lamp to be removed therefrom and replaced with a new one. This allowed the convenient replacement of the fluorescent lamp as needed when they become spent (i.e., burned out).
[0011] The fluorescent lamp lens assembly of U.S. Pat. No. 6,179,443 has achieved significant commercial success. However, as noted above, it was employed by affixing it to the rear surface of the end frames and mullions of the doorway. By being affixed to the rear inside surface of the end frames and mullions, the heat produced by the lamps unavoidably escaped from the lamp assembly into the interior of the refrigerated space. The escaping heat served no purpose and merely increased the costs of maintaining the low temperature of the refrigerated space.
[0012] At the same time, heating strips are often employed inside the end frames and mullions to heat the same and reduce condensation that would otherwise occur due to the difference in temperatures between the refrigerated space and the ambient air. Thus, while heat is added to the end frames and mullions for a meaningful purpose, heat from the lamp assemblies is wasted. Typically, the wasted heat increases the energy bill on the order of $50 or more per door per year.
[0013] Accordingly, there presently exists a need in the commercial refrigerator art to use the unavoidable heat that escapes from a lamp assembly that illuminates the shelving to heat the end frame or mullion to which it is affixed and thereby eliminate or reduce the need for internal heating strips in the end frame or mullion.
[0014] Therefore, it is an object of this invention to provide an improvement which overcomes the aforementioned inadequacies of the prior art devices and provides an improvement which is a significant contribution to the advancement of the commercial display refrigerator art.
[0015] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly including a lamp assembly that is integrated into an end frame or mullion of a commercial display refrigerator such that the waste heat from the lamp is constructively used to heat the end frame or mullion to prevent condensation.
[0016] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly that results in a lamp being positioned closer to the end frame or mullion and therefore further away from the shelves such that lighting of the shelving is improved.
[0017] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly that may accommodate different-diameter fluorescent lamps.
[0018] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly with a protected lamp thereby minimizing lamp breakage.
[0019] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly having a lamp that will remain stable in cold temperatures.
[0020] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly that includes a lens that redirects the light to the product and out of the customer's eyes.
[0021] Another object of this invention is to provide an integrated mullion and fluorescent lamp assembly that largely constitutes a sealed assembly that provides insulation for the lamp, thus allowing greater light output, while also providing heat to heat the mullion and prevent condensation.
[0022] The foregoing has outlined some of the pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
[0023] For the purpose of summarizing this invention, this invention comprises an integrated mullion and fluorescent lamp assembly for commercial display refrigerators including a lamp assembly that is integrated into an end frame or mullion of a commercial display refrigerator such that the otherwise waste heat from the lamp is constructively used to heat the end frame or mullion to prevent condensation. In lieu of the prior art separate lamp assemblies that are merely affixed to the surface of the end frame or mullion, the integrated mullion and fluorescent lamp lens assembly includes an end frame or mullion that has a longitudinal interior cavity extending from one end to the other. Fluorescent lamp posts are affixed at each end inside a longitudinal cavity to operatively receive a conventional fluorescent lamp. A longitudinal lens is snapped into the longitudinal edges of the end frame or mullion to cover the longitudinal cavity and define a closed cavity for fluorescent lamp. Notably, the lamp is positioned further away from the shelving such that lighting of the leading edge of the shelving is improved.
[0024] Importantly, front and sides of the end frame or mullion serve as heat sinks to absorb the heat discharged from the fluorescent lamp and to thereby heat the end frame or mullion. The heat absorbed by the end frame or mullion reduces the amount of condensation that might otherwise occur on the end frame or mullion due to the difference in temperatures. Indeed, the need for heat strips in the end frame or mullion may be eliminated, or at least the wattage of the heat strips contained therein may be reduced.
[0025] Ancillary benefits to the integrated mullion and fluorescent lamp assembly of the invention include the ability to accommodate different-diameter fluorescent lamps, the ability to protect the lamp to minimize lamp breakage, the ability to stabilize the temperature of the lamp in cold temperatures and the ability to redirect the light to the product on the shelves and out of the customer's eyes.
[0026] The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings in which:
[0028] FIG. 1 is an exploded view of the prior art fluorescent lamp assembly of U.S. Pat. No. 6,179,443 to be affixed to the inside surface of a mullion.
[0029] FIG. 2 is a cross-sectional view of the prior art fluorescent lamp assembly of U.S. Pat. No. 6,179,443 affixed to the rear surface of a mullion;
[0030] FIG. 3 is a cross-sectional view of the integrated mullion and fluorescent lamp assembly of the invention showing a lamp assembly that is integrated into an end frame and into a mullion of a commercial display refrigerator such that the otherwise waste heat from the lamp is constructively used to heat the end frame and mullion to prevent condensation; and
[0031] FIG. 4 is a cross-sectional view of FIG. 3 along lines 4 - 4 showing the reflector and frame plugs that create a chimney effect within the ceiling.
[0032] Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0033] Referring to FIGS. 1 & 2 , the prior art fluorescent assembly 10 taught by U.S. Pat. No. 6,179,443 was intended to be utilized by affixing it to the planar rear surface 12 of an end frame 13 or mullion 14 facing the shelving supports 16 . Such a mullion-mounted fluorescent assembly 10 projected light onto the leading edge of the display shelves while minimizing glare on the glass refrigerator door 16 . Unfortunately, however, due to the fact that the fluorescent assembly 10 was merely affixed to the rear planar surface 12 of the end frame 13 or mullion 14 , the waste heat generated by the lamp 18 contained therein would escape to the interior of the refrigerated space. The waste heat would therefore increase the heat load on the refrigerated space and wastefully increase the energy needed to maintain the refrigerated space at the desired constant cool temperature.
[0034] Referring now to FIG. 3 , the integrated mullion and fluorescent lamp assembly 20 of the invention is integrated into the end frame 21 and/or mullion 22 by reconfiguring the end frame 21 and mullion 22 to each be open-ended along its rear side to removably accept a longitudinal lens 24 . More particularly, the integrated mullion and fluorescent lamp assembly 20 comprises the end frame 21 and mullion 22 having an integral front wall 26 , and opposing side walls 28 , preferably parallel to each other. The front wall 26 is configured to provide a seal with the door seal 30 when the door 32 is closed. The side walls 28 are configured with appropriate grooves or the like to allow cosmetic flashing strips 29 , preferably of a non-thermally conductive material such as plastic, to be mounted thereon that insulate the surfaces of the end frame 21 and mullion 22 . The front wall 26 combined with the side walls 28 are appropriately configured to form part of the door frame 34 of the display refrigerator 36 .
[0035] The leading longitudinal edges 38 of the side walls 28 of the end frame 21 and mullion 22 (or of the flashing strip 29 ) and the corresponding longitudinal edges 40 of the lens 24 are complementarily configured to be removably snapped together. While many configurations may exist, as shown in FIG. 3 , one configuration comprises forming a longitudinal undercut 42 along the leading edges 38 of the side walls 28 or flashing strip 29 . Complementarily, longitudinal tabs 44 with a hook 46 are provided along the longitudinal edge 40 of the lens 24 . The opposing tabs 44 and hooks 46 of the lens 24 are dimensioned relative to the longitudinal undercuts 42 of the side walls 28 of the end frame 21 and mullion 22 such that the lens 24 may be aligned and then push inwardly to snap into place with the hooks 46 engaging underneath the respective undercuts 42 , thereby removably securing the lens 24 about the rear opening across the side walls 28 of the end frame 21 and mullion 22 and defining a closed interior within the end frame 21 and mullion 22 .
[0036] Positioned between the opposing side walls 28 of the end frame 21 and mullion 22 is a lamp assembly 50 comprising one or more fluorescent tubular lamps 52 operatively mechanically and electrically connected between respective lampposts 54 . Preferably, if two or more shorted fluorescent lamps 52 are employed in lieu of a longer lamp 52 , they are installed collinearly. Multiple long lamps 52 may alternatively or in combination be employed with a short lamp if desired in which case they may be positioned parallel to each other. Also, the interior cavity defined by the front and side walls 26 & 28 may be dimensioned to accommodate different-diameter fluorescent lamps 52 . In each case, the heat produced by the lamp(s) 52 is substantially contained with the end frame 21 and mullion 22 by virtue of the closed system created by the lens 24 , and is therefore absorbed by the front and side walls 26 & 28 thereof to heat the same and reduce or prevent condensation that might otherwise occur. Furthermore, the closed system serves to stabilize the temperature of the lamp(s) 52 and therefore maximize their light efficiency. Finally, the fact that the lens 24 protects the lamp(s) 52 minimizes lamp breakage should a product pulled from the shelving be inadvertently knocked against the end frame 21 or mullion 22 .
[0037] The lens 24 preferably comprises a prismatic transparent or translucent lens of the type disclosed in U.S. Pat. No. 6,179,443 to direct the light emitted from the lamp(s) 52 onto the front of the shelving supported by the shelving supports 16 .
[0038] As shown in FIG. 3 , a longitudinal reflector 60 may optionally be installed between the side walls 28 to reflect light from the lamp 52 outwardly toward the shelving 16 . Preferably, the longitudinal reflector 60 is installed by snapping it into place between appropriate longitudinal grooves found in the snap-on flashing strips 29 to maintain the arcuate shape of the reflector 60 . As shown in FIG. 4 , the reflector 60 may be shortened to not extend fully from top to bottom. Foam plugs 62 may be installed between the lens 24 and the mullion 22 to block air flow. As a result, a chimney effect is created with heat from the lamp 52 flowing upwardly to then pass between the upper foam plug 62 and the reflector 60 and then into mullion 22 , to then flow downwardly along the mullion to flow underneath the lower plug 62 to return to the lamp 52 , thereby creating a circulatory flow of air to increase the warming of the mullion 22 .
[0039] As used in the claims, the term “mullion” shall mean an end frame and/or a center frame between two doors.
[0040] The present disclosure includes that contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.
[0041] Now that the invention has been described, | An integrated mullion and fluorescent lamp assembly for a display refrigerator comprising a mullion including an open-ended rear side, a longitudinal lens removably positioned over the open-ended rear side of the mullion and a lamp assembly positioned within the mullion, whereby heat from the lamp assembly heats the mullion. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a modified gas gauge of simple yet highly effective construction which has numerous advantages including convenience, compactness and easy portability. More particularly, it is concerned with a modified gas gauge having a conduit, coupling structure for inserting the gauge into a gas meter and structure for simulating first and second flow conditions pertaining to a gas supply system. In this fashion, the user may perform multiple gas flow tests from a single location outside of a house or other building without the need for many trips into the building to establish different gas flow situations.
2. Description of the Prior Art
Field personnel for natural gas companies must perform many tests when connecting a gas line, such as when initiating service for a commercial or residential customer. Typically, numerous trips into the premises are required in the course of the turn-on procedure. For example, when turning on the gas supply for a residential customer, the meter must be checked while the pilot light for one of the gas appliances is lit, with all the other appliances shut off. This meter test requires two additional trips into the house for the purpose of lighting and then extinguishing the pilot light in a selected appliance. What is needed is a device which will simulate, at the test site, conditions within the house such as the consumption of gas by a pilot light so that multiple time consuming trips in and out of buildings may be eliminated.
SUMMARY OF THE INVENTION
The problems outlined above are in large measure solved by the modified gas gauge flow tester in accordance with the present invention. That is to say, the gauge hereof serves to simulate selected flow conditions so as to reduce the number of trips to and from a test site.
The present invention broadly includes a fluid conveying conduit having two ends, structure for coupling one of the ends to a fluid transfer assembly (e.g., a conventional gas meter), and apparatus operably connected with the conduit for simulating first and second flow conditions of different magnitude. The second simulation apparatus has first and second positions such that in the second position the second simulation apparatus effectively controls the flow rate through the conduit at a relatively lower second level, while in the first position the first simulation apparatus effectively controls the flow rate at a relatively higher first level.
In preferred forms the second simulation apparatus includes an apertured, shiftable valve body which cooperatively permits the first flow condition when in the open setting and restricts flow to the second level in the closed position. In an alternative embodiment, a conventional valve body is utilized, and the second flow rate is accomplished by positioning an aperture between the first end of the conduit and the valve body.
As one example, the modified gas gauge device can be used in the course of a turn-on order for a residential gas supply system including a meter and a house line. The service technician disconnects the meter from the house line and inserts the device into the meter. The valve body is then shifted to the closed position to simulate the consumption of gas caused by the pilot light of one appliance at the end of the house line. By such shifting of the valve body the technician avoids two trips into the house which would otherwise be necessary to light and extinguish a pilot light.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic view of a typical residential gas system;
FIG. 2 is a side elevational view of the modified gas gauge/tester in accordance with the present invention;
FIG. 3 is an exploded view of a stopcock valve assembly utilized in the present invention;
FIG. 4 is a sectional view taken along line 4--4 of FIG. 2, illustrating the valve body in the closed position;
FIG. 5 is the sectional view of FIG. 4 with the valve body in the open position;
FIG. 6 is a view similar to that of FIGS. 4 and 5 for another embodiment, illustrating the alternative valve body in the closed position; and
FIG. 7 is a partial, elevational view of the embodiment of FIG. 6, which illustrates the alternative placement of the second aperture on the exterior of the conduit.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing in general, and FIG. 2 in particular, a modified gas gauge or device 10 in accordance with the invention broadly includes a conduit 12, coupling structure 14, first simulation apparatus 16, second simulation apparatus 18 and gauge assembly 20. Device 10 is adapted for insertion into fluid systems (e.g., metered gas systems) for the purpose of monitoring fluid flow therethrough and thereby checking the reliability of the gas meters.
In more detail, conduit 12 includes three 1/4 inch, externally threaded, black pipe nipples 22-26 which can be alternatively constructed of any suitable metal or synthetic resin. Conduit 12 could also be integrally formed. Internally threaded tee piece 28 has three ports, two of which are mated with nipples 22 and 24 as shown. Conduit 12 presents a first end 30 and a second end 32, with the two ends being in fluid communication.
Coupling structure 14 includes hollow, tapered, resilient, rubber-like plug 34 which is mated with nipple 22 at first end 30 in a manner to allow fluid to flow thereinto. Coupling structure 14 may be made from any resilient material such as a synthetic resin and is adapted for insertion into a standard gas meter. It will be readily understood that other dimensions and materials could be used for constructing coupling structure for other kinds of fluid systems.
First simulation apparatus 16 includes an internally threaded, 1/4 inch black pipe cap 36 having an aperture 38 therethrough. Aperture 38 is formed by using a number 33 size drill bit to drill a hole into cap 36 which is then threaded onto end 32 of conduit 12. The diameter of first aperture 38 is about 113 mils.
Referring to FIG. 3, second simulation apparatus 18 includes a stopcock valve assembly 40. Assembly 40 have a hollow valve frame 42 with valve ports 44 and internally threaded nipple ports 46 for respectively coupling with nipples 24 and 26 (as shown in FIG. 2). Still referring to FIG. 3, assembly 40 further includes valve member 48 having a frustoconical valve body 50, two aligned apertures 52, slot 53, operating lever 54 and threaded end 56 integrally formed on valve body 50. Washer 58 and nut 60 secure valve member 48 within valve frame 42 to complete assembly 40. Each of apertures 52 presents an identical diameter which is predetermined and relatively smaller than that of aperture 38. The diameter of each aperture 52 is preferably about 16 mils.
Referring once again to FIG. 2, gauge assembly 20 includes an externally threaded, 1/4 inch nipple 62 coupled with the third port of tee piece 28 and an internally threaded collar 64 which is mated to an externally threaded gauge 66. Gauge 66 is conventional in nature and suitable for measuring a range of gas pressures found in commercial and residential systems. Gauge 66 is in fluid communication with first end 30 of conduit 12.
Referring now to FIGS. 6 and 7, portions of an alternative embodiment of the present invention, namely device 110, are shown. Device 110 is in all respects and structure the same as device 10 except for two instances noted below. The first difference is ascertained by comparing FIGS. 4 and 6. The second is ascertained by comparing FIG. 7 with FIG. 2.
As to the first difference and referring now to FIGS. 4 and 6, the respective second positions of valve bodies 50 and 150 are shown. These are the closed position for both respective devices and it will be noted by observing lever 54 that the second simulation apparatus as depicted in FIG. 2 is in such a closed or second position. By comparing FIGS. 4 and 6 it will be readily understood that device 10 includes two opposed apertures 52 on valve body 50 (only one of which is visible in FIG. 4) while valve body 150 of device 110 includes no such apertures. Of course, if valve body 50 were solid rather than having a slot 53, one second aperture spanning the valve body would be sufficient.
As to the second difference, FIG. 7 depicts a portion of nipple 124, in all respects analogous to nipple 24 of device 10 except that a second aperture 152 is formed, having dimensions exactly the same as that of second apertures 52 of device 10. By referring to FIG. 2 it will be appreciated that nipple 24 contains no exterior apertures.
Referring now to FIG. 1, a gas supply system 68 suitable for supplying gas to a residential consumer is shown. The system 68 includes a gas main line (not shown), service line 70 connected to the main, shut-off valve 72, regulator 74, meter 76, and house line 78. House line 78 is in turn return operatively coupled with gas burning appliances 79 within the house. The system 68 services residence 80 equipped with gas-burning appliances (not shown) located therein. The gas main line, service line 70, shut off valve 72, regulator 74 and meter 76 collectively constitute a fluid transfer assembly 82 which must be tested and monitored independently from house line 78 as discussed below. Meter 76 includes a visually observable test mechanism such as an analog hand, and conventional flowpreventing seals (not shown). The appliances within residence 80 one each connected to house line 78 so as to be supplied thereby.
FIG. 1 is illustrative rather than exhaustive of the type of fluid system suitable for a device in accordance with the present invention. For example, a commercial gas system would be suitable for such use-also an industrial setting would be appropriate. Hence, the scope of this invention covers not only turn-on orders for residential gas customers but also includes diagnostic and repair procedures. Indeed, the invention is applicable to any fluid flow system, whether liquid or gas, which requires simulation of a plurality of predetermined flow rates by selectively utilizing apertures of various dimensions suitably corresponding to the required flow rates. Thus, the detailed procedure described below is meant simply as an illustration of one specific use for the present invention.
Referring now to the drawing in general, with specific attention to FIG. 1, a field technician (such as a gas service representative or the like) will arrive at the site of system 68 to turn on gas at residence 80. The procedure used by the technician will be described briefly by way of overview and then in more detail. In the course of turning on a residential gas supply associated with system 68, the technician will:
(a) disconnect meter 76 from house line 78 and remove any flow-preventing seals from meter 76;
(b) insert device 10 into meter 76;
(c) turn on shut-off valve 72 so that gas flows through meter 76 and device 10;
(d) check the amount of pressure created by the regulator 74 by reading gauge 66 with valve body 50 in the first (open) position;
(e) recheck regulator 74 by covering the first aperture 38 and reading gauge 66;
(f) remove device 10 from meter 76 and reconnect meter 76 to house line 78;
(g) check house line 78 by reading the meter test-hand;
(h) disconnect meter 76 from house line 78 and insert device 10 into meter 76;
(i) place valve body 50 in the second (closed) position;
(j) read the meter test-hand;
(k) remove device 10 from meter 76 and reconnect meter 76 to house line 78;
(l) read the meter test-hand twenty minutes later; and
(m) light the appliances.
All disconnecting and reconnecting of meter 76 and house line 78 is done at a suitable juncture such as shown by reference numeral 84, this being referred to as the downstream on output side of meter 76. Once the flow-preventing seals are removed from the meter 76, they are never reinserted therein. Any time the device 10 is inserted into meter 76 it is done by mating coupling structure 14 with meter 76 as at juncture 84.
After the shut-off valve 72 has been turned on in step (c) and gas is therefore flowing through meter 76 and device 10 out first aperture 38 into the atmosphere, step (d) is performed to check the regulator pressure. The technician expects a reading of about 4.0 ounces of pressure on gauge 66. This situation, referred to as a first flow rate, simulates the amount of gas flowing through system 68 to be delivered to the appliances when the appliances are operating at a typical flow rate (i.e. fluid transfer assembly 82 is delivering about 50 cubic feet per hour to the atmosphere at this point). The purpose of delivering gas to the atmosphere outside the house rather than checking the regulator pressure with the house line 78 connected to meter 76, is to prevent any accidents (within the house) which might arise from irregular flow pressure. Hence, it is more prudent to check the regulator pressure prior to performing tests involving house line 78.
Regulator 74 is rechecked in step (e) by covering the first aperture 38 (such as the service technician covering first aperture 38 with his thumb) and reading gauge 66. This is the so-called "lock-up" test, wherein the technician expects to get a reading of about 4.25 ounces of pressure as opposed to the 4.0 ounces expected in step (d) when the first flow rate is being simulated.
To digress briefly and referring to FIG. 5, the first position (i.e. open position) is shown wherein gas freely flows from first end 30 to first aperture 38 via slot 53. In this first position, the first flow rate is being simulated, wherein first aperture 38 is the smallest orifice within conduit 12 controlling gas flow from first end 30 to aperture 38. By casual inspection it will be noted that first aperture 38 is of relatively smaller diameter than slot 53, so that first aperture 38 controls the rate of gas flow in the first position. As mentioned above, the diameter of first aperture 38, which is about 113 mils, causes a first flow rate of about 50 cubic feet per hour. This first flow rate corresponds with a typical residential gas consumption rate and is suitable for checking pressure delivered by regulator 74. Thus it will be seen that the diameter of first aperture 38 is preselected to simulate the flow of natural gas through house lines 8 when gas-burning appliances within residence 80 are consuming gas at typical levels.
Referring to FIG. 4, the second position i.e. closed position) of device 10 is depicted. In this second position all gas must flow through aligned apertures 52 (only one of which is visible in FIG. 4. The diameter of each second aperture 52 is identical and relatively smaller than the diameter of first aperture 38; thus second apertures 52 control the rate of gas flow in the second position. The diameter of second apertures 52 causes a second flow rate of about 0.75 cubic feet per hour. This second flow rate corresponds with a typical residential gas consumption rate when the pilot light of one appliance only is lit. Thus it will be seen that the diameter of second apertures 52 is preselected to simulate the flow of natural gas through house line 78 when one gas burning appliance has its pilot light lit.
Returning to the procedure at step (f), the technician restores the configuration of FIG. 1 with the exception of leaving out the flow-preventing seals and the changed condition of the shut-off valve which is now in the open position. At step (g), there should be no movement of the meter testhand, since at this stage all appliances are shut off-there fore movement of the test-hand would indicate a leak within the house line 78 or connections between the house line 78 and the appliances. Thus, no meter test-hand deflection at step (g) is a confirmatory indication of a substantially leak-free house line.
Step (h) is analogous to steps (a) and (b). The act of placing valve body 50 in the second position in step (i) saves going into the residence 80 to turn on a pilot light of one appliance. The step of turning on a pilot light with the house line 78 connected to meter 76 was the prior technique for creating the second flow condition.
In step (j) a slight movement of the meter test hand is expected in order to determine that meter 76 is operating with sufficient sensitivity. That is to say, a slight deflection of meter 76 indicates that the meter is detecting a slight flow of gas in the second flow rate (i.e. the simulation of one pilot light lit in residence 80).
Step (k) is performed exactly as step (f). In the old method, an additional trip was required into the house, this time to shut off the pilot light previously lit in step (i) of the old method. Thus, steps (i) and (j) of the new method eliminate two time consuming, burdensome trips into the residence 80 in accordance with the present invention.
Step (l) involves waiting an appropriate amount of time to determine that there are no significant gas leaks within the house line 78. As an example, regulations might require that the house line lose no more than two cubic feet of natural gas per hour in which case a two-foot test-hand would be watched for twenty minutes. At the end of that time if the test-hand had been deflected one third or more of its total range, then an unsatisfactory leak rate would be indicated. Continuing with the regulatory example having a two-cubic-feet-per-hour standard, if the meter had a one-foot test-hand the waiting period in step (1) would be ten minutes. If the meter had a half-foot test-hand, the waiting period would be five minutes. In each case a testhand deflection of one third or more indicates violation of the two-feet-per-hour standard.
At step (m), and assuming that positive results have been attained on all previous steps, the pilot lights on all the appliances are lit so that the consumer may begin normal usage thereof.
With reference to device 110, partially illustrated in FIGS. 6 and 7, it will be noted that the exact procedure as above described will also be performed. While the steps will be identical, the difference will be in the second flow rate condition. At FIG. 6, showing the second position of valve body 150, it will be seen that no gas may flow out first aperture 38 in the closed position, therefore, the second flow rate condition will be simulated by the delivery of about 0.75 cubic feet of natural gas per hour to the atmosphere via second aperture 152 (see FIG. 7). Thus, devices 10 and 110 have identical second flow rate simulations, but device 10 vents gas via first aperture 38 while device 110 vents gas through aperture 152. The purpose of placing aperture 152 on the exterior of nipple 124 is to avoid possible problems that might arise with second aperture 52 in device 10. In particular, what is avoided is the accumulation of graphite, grit, dirt and the like at aperture 52. It will readily be understood that such a collection of debris is much less likely with second aperture 152 given its positioning on the exterior of nipple 124.
It will also be noted that in the first flow condition, device 110 will vent gas from both first aperture 38 and second aperture 152, resulting in a minutely greater first flow condition for device 110 than that of device 10. However, given the large difference in diameters for first aperture 38 and second aperture 152, there will be virtually no practical difference between the respective first flow conditions of devices 10 and 110. | Device (10) is provided for insertion into meter (76) in the course of testing gas system (68). Device (10) advantageously allows a technician to make fewer trips into residence (80) in the course of a gas turn-on procedure. House line (78) is first disconnected from meter (76) and device (10) is then inserted into meter (76) at (84). After an initial full flow check by passage of gas through aperture 38, valve body (50) is shifted to a closed position wherein gas flow is controlled by smaller apertures (52) so that a second flow rate is achieved simulating the pilot light of one appliance being lit in residence (80). In this fashion, two trips into residence (80), respectively to turn on and turn off one pilot light, are avoided. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a propellant charge igniter for insertion into a propellant charge carrier, e.g., a cartridge, said igniter having a flame guide tube leading from an ignition charge to a lead fuze, an ignition guide tube surrounding the lead fuze and means for completely expelling the ignition guide tube from the charge igniter to avoid undesirable glowing residue which can escape from the barrel of a weapon when the bottom of the cartridge is removed.
In order to be able to fire a projectile with a propellant charge as far as possible from a firing tube, it is necessary to ignite, in a controlled fashion, the propellant charge located in a propellant charge carrier, for example a cartridge. An effort is made in this regard to ignite the entire propellant charge in such fashion that a high initial pressure is rapidly produced and the pressure is then kept at a high level for as long as possible. Pressure peaks occurring locally within the propellant charge are undesirable in this context, since such peaks negatively affect the subsequent burning of the propellant charge and also have a negative effect on the lifetime of the firing tube. Propellant charges are therefore not only ignited at one end, but special propellant charge igniters with ignition guide tubes are used.
A propellant charge igniter is known from DE 38 29 657 Al in which a lead fuse located in an elongated ignition guide tube (wound tube) is ignited by means of an igniting charge. The ignition guide tube, located concentrically with respect to a flame guide tube, has its end at a bottom-part side projecting into a bottom part. A separating charge is located within the outline of the bottom part of the flame guide tube. The propellant charge igniter also has a metal jacket located between the separating charge and the ignition guide tube. An annular seal is located in a circumferential recess in the flame guide tube at the end of the metal jacket facing away from one bottom end of the bottom part, the seal acting as a valve with the metal jacket and the flame guide tube and, in the open position, permitting the hot combustion gases of the separating charge to flow toward the ignition guide tube.
Ignition of a propellant charge with the propellant charge igniter according to DE 38 29 657 Al takes place in such fashion that the ignition charge initially ignites the lead fuse composed of annular ignition-material tablets. Then the lead fuse ignites the propellant charge through openings in the ignition guide tube, the propellant charge, in turn, then igniting the separating charge through priming holes in the bottom part. The hot gases from the separating charge force the annular seal aside and separate the ignition guide tube in the area of the end of the bottom part facing away from the bottom side. The separated part of the ignition guide tube is then hurled out of the firing tube by the gases flowing out of the firing tube, while the other part of the ignition guide tube remains connected to the bottom part.
This arrangement has the disadvantage that an undesirable glowing residue can still escape from the barrel of the weapon when the cartridge bottom is pulled out or removed.
SUMMARY OF THE INVENTION
An object of the invention is to provide a propellant charge igniter in which the danger of afterglow is avoided.
The solution to this problem is provided in accordance with the propellant charge igniter of the present invention wherein means are provided for effecting complete expulsion of the ignition guide tube from an annular chamber provided between a base of the igniter and the flame guide tube.
In the propellant charge igniter according to the invention, a powder train comprises an expeller charge for completely expelling the ignition guide tube out of the annular chamber, which commensurates with a combustion chamber at an end facing toward the bottom end of the igniter. Through the transition of the annular chamber to the combustion chamber, the gases generated in the combustion chamber by the combustion of the expeller charge can press against an end of the ignition guide tube facing the bottom end and expel it from the annular chamber. As a result, after firing, only metal parts remain on the bottom part or base of the igniter and the bottom part itself remains in the barrel of the weapon, which cool rapidly because of the good heat conduction of the metal parts. As a result of the complete expulsion of the ignition guide tube, afterglow of material in the bottom part or base of the igniter is avoided.
Since the combustion chamber and the annular chamber are located one behind the other in the lengthwise direction, it is not necessary to provide a metal jacket separating the two chambers and to provide a valve arrangement between the chambers. The annular chamber is preferably delimited by a conical inner surface of the bottom part which essentially tapers toward the bottom end or face of the igniter. This conical inner surface cooperates with a conical outer surface of the ignition guide tube, whose angle of inclination to the lengthwise axis of the propellant charge igniter corresponds to the taper angle of an inner surface of the bottom part in the annular chamber area, in such a way that a secure connection of the ignition guide tube with the bottom part before firing is guaranteed. The conical surfaces transmit impact or pressure forces on the tip of the propellant charge tube safely to the bottom part. As a result, insertion of the propellant charge igniter into a jacket filled with a propellant charge is also facilitated. The two conical surfaces also permit, however, an especially reliable separation of the ignition guide tube from the bottom part, since when the ignition guide tube is expelled, frictional forces between the ignition guide tube and the bottom part are effective only over a short area.
Preferably the bottom part, at its end facing away from the bottom side, has a toothed area on the inside meshing with the ignition guide tube. As a result of these teeth, the bottom part hooks into the ignition guide tube in such fashion that a reliable connection is provided during the transport of the propellant charge igniter. For a secure connection between the bottom part and the ignition guide tube, the bottom part can also be pressed inward at its end away from the bottom side, squeezing the ignition guide tube. This squeezing, which takes place after the ignition guide tube and the bottom part have been fitted together, creates in the ignition guide tube, the zone which abuts the end of the bottom part. The hooking and the zone formed by the squeezing create a situation such that the ignition guide tube cannot be slid further into the bottom part or be pulled out as a result of axial upsetting or by a defined axial tensile stress. As a result, the frictional force provided during the manufacture of the propellant charge igniter and adjusted to the strength of the expeller charge remains intact so that ammunition provided with the propellant charge igniter according to the invention can even be dropped by parachute. In addition, the inner surface of the bottom part can be glued to the outer surface of the ignition guide tube. One or more of the above measures for connecting the ignition guide tube with the bottom part ensures that the propellant charge igniter will display the required strength in drop tests.
In order to prevent ignition of the expeller charge by the combustion gases of the lead fuse, an immovable annular seal is located in an annular groove in the flame guide tube, said seal being in the annular groove and abutting the ignition tube and sealing the flame guide tube from the ignition guide tube surrounding it.
The expellable ignition guide tube of the propellant charge igniter, which is preferably a wound tube made of a fiber material with a plastic matrix, can be made of a combustible, consumable material which therefore largely burns up during ignition and burning of the propellant charge of the cartridge.
If especially resistant jacketing of the lead fuse is desired, the ignition guide tube can be wound from a glass-fiber-reinforced plastic.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional advantageous embodiments and improvements on the invention will be apparent from the following detailed description with reference to the accompanying drawings wherein:
FIG. 1 is a longitudinal section through the bottom-end and of a propellant charge igniter, built into a bottom part of a cartridge;
FIG. 2 shows the entire propellant charge igniter shown partially in FIG. 1 in longitudinal section, and
FIG. 3 shows an enlarged partial sectional view of the bottom end of an ignition guide tube built into a bottom piece.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a propellant charge igniter 10 assembled into a cartridge bottom part or base 12 which has a cylindrical shape turned from metal. Cartridge bottom part 12 is open at its upper end away from the bottom end 14. A combustible cartridge jacket 16 abuts the upper end of cartridge bottom part 12 facing away from bottom end 14, said jacket containing at its forward end a projectile (not shown). Cartridge bottom part 12 and cartridge jacket 16 are filled with a propellant charge 18 composed of individual pourable propellant charge grains or particles 20, thus together forming a propellant charge carrier.
A centrally disposed opening 22 with a thread is provided in the cartridge base 12, into which the opening the propellant charge igniter 10 is threaded. Propellant charge igniter 10 has a bottom part or base 24 with a bottom end or surface 26 which extends coaxially with respect to the cartridge bottom part 12 and another end facing away from the bottom end 26 which other end does not project beyond an edge 30 of the cartridge bottom part 12 facing away from the bottom end 14. A fuse 32 with a cylindrical fuse housing 33 is screwed into bottom part 24, said fuse having an electrically ignitable primary ignition element 34 and a triggering charge 36 ignitable thereby. Ignition charge 36 is provided in a hollow chamber 38 in the bottom part 24, which is open in a direction away from the bottom face 26 and makes a transition there to a flame channel 42 extending along a lengthwise axis 40 of propellant charge igniter 10, said channel formed by a flame guide tube 44 made of metal. Flame guide tube 44 is permanently attached to the bottom part 24.
An outer surface 46 of the end area of flame guide tube 44 facing away from bottom face 26 and an inner surface 48 of bottom part 24 located opposite this area delimit an annular chamber 49 into which an ignition guide tube in the form of a wound tube 50 projects. An end of the annular chamber 49 facing toward the bottom face 26 is abutted by a combustion chamber 52 in which an expeller charge 54 is located. Expeller charge 54 consists of annular propellant tablets surrounding a tapered area of the flame guide tube 44. Wound tube 50 consists of fiber-reinforced plastic, especially of plastic reinforced with high strength textile fibers consumable by combustion, and has at its end facing bottom face 26 a thickened portion 56, whose outer surface 58 tapers towards the bottom face 26. The slope angle of the outer surface 58 relative to the lengthwise axis 40 of the propellant charge igniter corresponds to that of the inner surface of the bottom part 24 in the vicinity of the annular chamber 49. Wound tube 50 has an annular end face 60 facing combustion chamber 52. A lead fuse 64 is located in the wound tube 50 which has radially extending openings 62. Wound tube 50 surrounding a portion of the flame guide tube 44, which is essentially circularly cylindrical in the vicinity of annular chamber 49, is sealed off from the flame guide tube 44 by means of an annular seal 68 located in an outer annular groove 66 of the flame guide tube 44. Annular groove 66 and annular seal 68 are designed such that the annular seal 68 is immovable in the annular groove 66.
In order to facilitate assembly of the propellant charge igniter 10, bottom part 24 has a metal intermediate part or element 70 into which flame guide tube 44 is screwable in such fashion that the expeller charge 54 is held around the flame guide tube 44 between a shoulder 72 and the intermediate part 70. Intermediate part 70 is located in a concentric lengthwise bore 74 of the bottom part 24 and is held by pins 76 which project through the bottom part 24 into the intermediate piece 70. The essentially hollow cylindrical bottom part 24 also has radially extending priming openings 78, through which combustion chamber 52 communicates with the inner chamber of the cartridge, filled by propellant charge 18 and surrounding bottom part 24.
In order to make the connection between wound tube 50 and bottom part 24 as resistant to impact as possible, bottom part 24, at its end 28 facing away from the bottom face 26, has teeth 80, preferably a shallow thread as shown in FIG. 3. The teeth engage wound tube 50. Bottom part 24 is also crimped or compressed radially inward at its end 28 facing away from the bottom face 26 and surrounding the wound tube 50. Compression forms a crimped zone 81 in the wound tube 50 which abuts upper end 82 of the bottom part 24. Between the conical outer surface 58 of the wound tube 50 and the conical inner surface 48 of bottom part 24, a layer of adhesive 83 can also be provided. In order to seal off the wound tube 50 at the end 28 facing away from the bottom face 26, a plug 84 is provided as shown in FIG. 2. In addition, the wound tube 50, at its forward end 28 facing away from the bottom face, is provided with a tip 86 which facilitates insertion of propellant charge igniter 10 into poured propellant charge 18. In addition, fitting of the propellant charge igniter 10 is facilitated by a thin covering 88 made of thermoplastic plastic, preferably a shrink tube, which extends over the entire wound tube 50 and over the area of bottom part 24 containing the priming openings 78, and protects the propellant charge igniter 10 against the penetration of moisture.
The electrically actuatable ignition-triggering element 34 is triggered to ignite propellant charge 18. Element 34 ignites ignition charge 36 whose hot gases then pass through flame channel 42 to lead fuse 64. The hot compressed gases from lead fuse 64 break the covering 88 over openings 62 and ignite propellant charge 18. The propellant charge gases then accelerate the projectile and, breaking through the covering 88 arranged over priming openings 78, pass through the openings into combustion chamber 52. Expulsion charge 54 located in combustion chamber 52 then ignites, and its gases act on the annular end 60 of wound tube 50, which then breaks loose from its frictional connection with bottom part 24. The thickness of expulsion charge 54 is selected so that the force generated by the compressed gases overcomes the force of friction, the force in adhesive layer 83, and the force of teeth 80. Wound tube 50, after coming loose from its connection with bottom part 24, is expelled by the suction effect of the propellant charge gases out of the impact bottom area of the weapon in order to burn better in the erosive gas stream. Undesirable early ignition of expulsion charge 54 is prevented by annular seal 68 in propellant charge igniter 10. | The invention relates to a propellant charge igniter mountable in a propellant charge carrier or in a cartridge. Propellant charge igniter is provided with an expulsion charge to avoid breech flash, said charge being suitable for driving an ignition guide tube completely out of an annular chamber formed between a bottom part and a flame guide tube of the propellant charge igniter. | 5 |
BACKGROUND OF THE INVENTION
[0001] The volume of information, such as data or multimedia content, for example, exchanged in mobile radio networks based on packet transmission is growing all the time. Since requesting information using the keypad of a mobile radio receiver is not very convenient, it is possible to request the desired information using so-called push services. In this case, information is automatically delivered by a server to the mobile radio receiver without the latter having explicitly requested the specific data.
[0002] The mobile radio user typically specifies a group of topics or a general information field, according to which the desired information is then delivered to the user on his/her mobile radio receiver. In technical terms, push services are network-initiated point-to-point services.
[0003] The basic design of a possible push service system is described in the TR 23.974 specification of the 3GPP (3rd Generation Partnership Project) organization.
[0004] Problems emerge, however, because the information transmitted using the push service is not delivered to the mobile radio user following an actual request by the user. Mobile radio receivers only have a limited storage capacity for incoming information. Problems therefore can arise because the sender of the information does not know whether he/she can still send the information to the mobile radio receiver.
[0005] Incoming information is usually indicated by the mobile radio receiver with the aid of an acoustic signal. If information is continually arriving in the mobile radio receiver, this constitutes an annoyance for the mobile radio subscriber. It is therefore desirable to find a way of receiving push services with which the user of this service is not constantly disturbed by incoming messages.
[0006] Moreover, with known push services there is the problem that, when a large volume of data is received, the user has difficulty deciding which data is important for him/her and which is less important. It is therefore desirable for the user of push services to receive the data in accordance with its relative importance.
[0007] An object of the present invention is, therefore, to provide an improved system for the transmission of data that has not been explicitly requested in a mobile radio system.
[0008] Accordingly, the system of the present invention for the transmission of data that has not been explicitly requested in a mobile radio system includes an application computer, a transmission network and a mobile radio receiver. The application computer may be, for example, an application server which sends the push services to the mobile radio receiver via a transmission network; for example, an Internet protocol connection.
[0009] The transmission network is a network which enables the connection between the application computer and the mobile radio receiver. The transmission network may be, for example, a GPRS (General Packet Radio Service) network.
[0010] The mobile radio receiver is a terminal which supports the use of push services.
[0011] If information is to be forwarded from the application computer to the mobile radio receiver, it is only sensible if the transmission network knows how much storage space is available to the mobile radio receiver to store push service information. For this reason, the mobile radio receiver indicates to the transmission network how much storage space is still available to it for storing the push services.
[0012] In a preferred embodiment of the present invention, the mobile radio receiver also indicates to the transmission network when no more storage space for data is available in the mobile radio receiver.
[0013] If the need should nevertheless arise to send information to the mobile radio receiver even though storage space is no longer available in the mobile radio receiver, there are basically two options. On the one hand, information not sent can be buffered. As soon as storage space becomes available in the mobile radio receiver once again, the buffered information is forwarded to the mobile radio receiver.
[0014] On the other hand, according to one embodiment of the present invention, it is also possible for the mobile radio receiver to release already occupied storage areas for overwriting with received information. This is conceivable, for example, for storage areas to which less relevant information has been written. The user has the option here of defining which information he/she considers less important, or which particular storage areas are to be released for overwriting with more important information, respectively.
[0015] In another preferred embodiment of the present invention, the transmission network has a storage area for buffering data received from the application computer. The storage area may be any known type of known storage system. The information of the push service is forwarded from the application computer to the transmission network. If it is not immediately possible to forward the information to the particular mobile radio receiver, the information is buffered in the storage area. Thus, it is always possible to send data from the application computer to the transmission network. As soon as the mobile radio receiver is ready to receive again, the buffered data is forwarded from the storage area to the mobile radio receiver.
[0016] The forwarding of the buffered data depends on the information indicated by the mobile radio receiver. For instance, if the mobile radio receiver indicates to the transmission network that no storage is currently available for receiving information, then the storage area stores the data intended for the mobile radio receiver until the mobile radio receiver indicates to the transmission network that sufficient storage space is again available for receiving the data. The information is exchanged here via the air interface.
[0017] In a further preferred embodiment of the present invention, the transmission network has a network computer which initiates the transmission of data to the mobile radio receiver. The network computer receives from the mobile radio receiver information relating to its available storage capacity. The initiation of a transmission by the network computer is performed depending on the information indicated by the mobile radio receiver. The network computer thus executes certain control functions in the transmission system. The network computer knows which data is buffered in the storage area, or which data transmission to the mobile radio receiver has not yet been executed.
[0018] The present invention also relates to a system for the transmission of data that has not been explicitly requested in a mobile radio system, in which the mobile radio system includes an application computer, a transmission network and a mobile radio receiver, wherein the mobile radio receiver notifies the transmission network of information relating to the transmission of data.
[0019] In a preferred embodiment of the present invention, the information of the mobile radio receiver indicates to the transmission network when the data is to be sent to the mobile radio receiver. For this purpose, the transmission network is notified of a time window which is best for the data of the push service to be sent to the mobile radio receiver. The background of this is that the user does not want to be continually disturbed by receiving the push services. As a result of this procedure, the user always knows exactly when new push service data may arrive. In this case, the mobile radio subscriber determines the time of transmission via an input on his/her mobile radio receiver. It is also conceivable, however, for the network operator to determine the time of transmission; e.g., depending on the network load.
[0020] In another preferred embodiment of the present invention, the mobile radio receiver transmits the desired time of transmission of the data to a network computer, which initiates the transmission accordingly.
[0021] In a further preferred embodiment of the present invention, the information of the mobile radio receiver indicates to the transmission network the order in which the data is to be sent to the mobile radio receiver. If a user has subscribed to a number of push services, he/she can assign a particular value to each push service. If several push services arrive, the data is transmitted to the mobile radio receiver in accordance with their relative value; that is to say, with a higher or lower priority. For instance, it is possible to assign stock market information a higher priority than sports information. A new item of stock market information is then forwarded to the user more quickly than a new item of sports information. It is also possible for the network operator to specify the relative values.
[0022] The same applies analogously when a storage area is used to buffer information received from the application computer. The processing, or forwarding, of the buffered information is again performed on the basis of the relative values assigned to the push service to which the user has subscribed.
[0023] The buffered data is forwarded depending on the information indicated by the mobile radio receiver. The user thus determines in which way he/she wishes to receive the push services.
[0024] The network computer receives the information relevant for the time, or order, of transmission from the mobile radio receiver. The network computer thus executes certain control functions in the transmission system. For instance, it initiates the transmissions from the transmission network (i.e., the storage area), to the mobile radio receiver.
[0025] Additional features and advantages of the present invention are described in, and will be apparent from, the following Detailed Description of the Invention and the figures.
BRIEF DESCRIPTION OF THE FIGURES
[0026] FIG. 1 shows a schematic representation of a system for the transmission of data that has not been explicitly requested in a mobile radio system.
[0027] FIG. 2 shows a schematic representation of a system for the transmission of data that has not been explicitly requested in a mobile radio system in the case of transmission dependent on relative values.
DETAILED DESCRIPTION OF THE INVENTION
[0028] FIG. 1 shows an application computer 1 , a transmission network 2 having a storage area 4 , and a network computer 5 . FIG. 1 also shows a mobile radio receiver 3 . Push service data is, as indicated by the arrow 7 , sent from the application computer 1 to the transmission network 2 . The data is then buffered in the storage area 4 . As indicated by the arrow 8 , the network computer 5 receives from the mobile radio receiver 3 information relating to the available storage capacity in the mobile radio receiver. Depending on this information, the data stored in the storage area 4 is sent, as shown by the arrow 10 , to the mobile radio receiver 3 .
[0029] If, for example, a large amount of information is to be sent from the application computer 1 to the transmission network 3 , and the network computer 5 has learned from the mobile radio receiver 3 that the latter currently does not have sufficient storage space available for receiving the information of the application computer 1 , the data is buffered in the storage area 4 . As soon as sufficient storage space is once again available to the mobile radio receiver 3 , (e.g., because the user has read old information and then deleted it), the information is sent to the network computer 5 . Accordingly, network computer initiates a forwarding of the information buffered in the storage area 4 to the mobile radio receiver 3 .
[0030] In addition, if the mobile radio receiver 3 indicates to the network computer 5 that there is no longer sufficient storage space available to it for receiving new information, it is possible for the mobile radio receiver 3 to release storage areas for overwriting with newly received data. It is also possible for information already read by the user, but which nevertheless continues to be stored in the mobile radio receiver, to be overwritten. The information as to which storage areas can be overwritten is forwarded to the network computer 5 under the user's control. The network computer 3 initiates the further transmission accordingly.
[0031] FIG. 2 shows a further exemplary embodiment of the system according to the present invention for the transmission of data that has not been explicitly requested in a mobile radio system. The elements of application computer, transmission system, storage area, network computer and mobile radio receiver are represented in FIG. 2 analogously to those explained above with reference to FIG. 1 . Arrows 6 , 7 , 8 indicate that information may arrive from the application computer 1 sequentially in the transmission network 2 ; i.e., the storage area 4 .
[0032] In one exemplary embodiment, data buffered in the storage area 4 is sent sequentially in series from a particular point in time to the mobile radio receiver 3 . As such, the first data stream 9 is sent first, followed by the data stream 10 and finally the data stream 11 . In this case the user specifies to the network computer 5 via the mobile radio receiver 3 the time information relating to when he/she wishes to receive the data of the push service.
[0033] In another exemplary embodiment, data relating to different push service topics is sent from the application computer 1 to the transmission network 2 . For instance, traffic bulletins are received first via the data stream 6 . This is followed by weather reports via the data stream 7 , and finally politics news via the data stream 8 . The data is buffered in the storage area 4 . Since weather information has the highest priority for the user, and politics news is more important to him/her than traffic bulletins, the user has accordingly notified the network computer 5 that, in the case of buffered information, he/she always wishes to receive the weather information first, then the politics news, and finally traffic bulletins. Accordingly, weather information is sent first via the data stream 9 , then politics news is sent via the data stream 10 , and finally traffic bulletins are sent via the data stream 11 from the storage area 4 to the mobile radio receiver 3 .
[0034] This procedure also may be configured for use only if buffering is used because of a lack of storage capacity in the mobile radio receiver 3 . Furthermore, it is possible for push service information always to be buffered for a given period of time so that a selection based on its relative importance may be made. Moreover, a combination with a time-dependent transmission is accordingly also possible.
[0035] Although the present invention has been described with reference to specific embodiments, those of skill in the art will recognize that changes may be made thereto without departing from the spirit and scope of the present invention as set forth in the hereafter appended claims. | A system and method are provided for transmitting data that has not been explicitly requested in a mobile radio system which includes an application computer, a transmission network, and a mobile radio receiver. The mobile radio receiver indicates to the transmission network how much storage space is available in the mobile radio receiver for storing data. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to cotton cleaning devices, and particularly to a cotton cleaning machine mountable directly on a cotton gleaner or scraper for separating dirt and debris from scrap cotton gathered by the scraper.
2. Description of the Prior Art
Devices generally referred to as cotton gleaners or cotton scrapers are commonly employed to traverse ground between cotton plants in order to recover cotton from a field after normal picking procedures have been completed. Such a gleaner or scraper is disclosed in U.S. Pat. No. 2,670,584, issued Mar. 2, 1954 to W. E. Rood, Jr. et al. Basically, these cotton scrapers employ an endless belt conveyor which engages cotton on the ground as the belt passes over a lower pulley on which the belt is mounted, and carries the gathered cotton upwardly along the lower run of the belt. While the cotton thus gathered can be merely deposited in a bin adjacent the upper end of the run of the belt, generally a further arrangement is provided for taking the gathered cotton from the endless belt and transmitting the cotton to a further point for ultimate discharge from the scraper. This is accomplished in cotton scrapers made under U.S. Pat. No. 2,670,584 in several manners, with a model manufactured in approximately 1960 or 1961 employing a drag chain device to achieve such further conveyance. Models manufactured immediately after the drag chain model use additional series of belts, with perhaps three belts being employed in all, and the intake end of each subsequent, or downstream, belt being disposed beneath the discharge, or upper end, of the previous, or upstream, belt from which the particular belt receives the cotton. In this manner, each belt after the first, or gathering, belt carries the gathered cotton on the upper run thereof, instead of the lower run as in the case of the initial belt.
Around 1964 or 1965, a basket was attached to the then current model of these cotton scrapers for catching the cotton as it is discharged.
A difficulty encountered with the continued use of older models of the cotton scraper, and particularly those made under U.S. Pat. No. 2,670,584 during the years 1960 to 1965, is that current EPA requirements placed on the ginning of cotton have made it economically necessary that the cotton gathered by a cotton scraper be cleaned prior to insertion into the gin in order to reduce ginning costs and increase the growers net yield of cotton per acre, while complying with the increasingly stringent requirements imposed on ginning operations by the Federal Government.
It should also be mentioned that although in theory the cotton scrapers as discussed above will operate with only a single endless belt at each stage of the scraper, from gathering to discharge, in practice it has been found that a plurality of belts disposed in parallel advantageously form each stage of such scrapers. These parallel belts are spaced slightly from one another so as to form gaps between them.
Cotton is conventionally cleaned by the use of a sawtooth drum used in combination with a doffer which removes the clean cotton from the drum. Examples of such cleaners can be found in U.S. Pat. No. 3,528,138, issued Sept. 15, 1970 to R. L. Elder; U.S. Pat. No. 3,382,544, issued May 14, 1968 to F. A. Moore; and U.S. Pat. No. 3,150,417, issued Sept. 29, 1964 to H. C. Word. These known cleaners, however, are specifically intended for use on the discharge of a conventional cotton-picker, and are not suitable for use with a cotton scraper. Further, the devices set forth in the aforementioned prior patents rely on fluid pressure to feed cotton into them, which pressure is not available on a cotton scraper, and which pressure in any event tends to create uneven feed into the device, and generally make inefficient the operation of the cleaner.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an attachment for an existing cotton scrapers which will permit cotton recovered by a scraper to be thoroughly cleaned prior to the cotton being fed to a cotton gin.
It is another object of the present invention to provide an attachment readily adaptable for use with several different models of existing cotton scrapers.
It is yet another object of the present invention to provide a cotton cleaning device capable of receiving cotton, dirt and debris or trash, under the fall of gravity, and without compaction of the cotton caused by the pressure of a fluid current feed of the cotton.
These and other objects are achieved according to the present invention by providing a cotton cleaning attachment having: a separator section mountable on a scraper at the discharge end of the scraper for receiving scrap cotton, dirt and debris or trash downwardly under the force of gravity from the scraper, and separating the dirt and trash from the cotton so as to clean the latter; and a transfer section also mountable on the scraper and arranged adjacent the separator section for removing clean cotton from the separator section and feeding the cotton as appropriate for further processing of the recovered and cleaned material.
The separator section preferably includes a drum rotatably mounted on the scraper, and provided with an outer circumferential surface having sawteeth aranged thereon for grasping the scrap cotton while permitting the dirt and trash to fall away from the cotton. A cage is arranged extending beneath the drum from adjacent the discharge end of the scraper for facilitating in retention of cotton on the drum while permitting the dirt and debris to fall away from the drum. The cage advantageously includes a plurality of spaced, substantially parallel rods arranged so as to curve around the adjacent lower periphery of the drum and in spaced relationship therefrom.
The cage further includes a pipe mounted on the scraper and disposed between an adjacent end one of the rods and the discharge end of the scraper. This pipe has a diameter larger than the diameter of the rods, and acts as a guide for directing the cotton, dirt and trash dischargd from the scraper into the space between the outer circumference or periphery of the sawtooth drum and the rods which form the combing portion of the cage.
The transfer section includes a fan rotatably mounted adjacent the drum, and also adjacent end one of the rods so as to be spaced from the discharge end of the scraper, and from the pipe associated with the cage. This fan acts as a doffer for removing cotton from the sawteeth of the drum, with the latter being disposed between the fan and the pipe portion of the cage.
A housing is mounted on the scraper so as to receive the fan, with the housing including a substantially horizontal surface arranged above the fan for diverting the cotton downwardly toward a blower carrying the cleaned cotton to a conventional storage bin, and the like.
These, together with other objects and advantages which will become subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings formimg a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary, schematic, perspective view showing a cotton scraper provided with a cleaning attachment according to the present invention.
FIG. 2 is an enlarged, fragmentary, section view taken generally along the line 2--2 of FIG. 1.
FIG. 3 is a fragmentary, sectional view taken generally along the line 3--3 of FIG. 2.
FIG. 4 is a fragmentary, schematic, perspective view showing the principal parts of a cleaning attachment according to the present invention together with the head pulley of an associated scraper.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to the Figures of the drawings, a cotton scraper 10 of conventional construction is shown as having a belt 12 at the uppermost portion thereof, which belt 12 includes a plurality of spaced, substantially parallel strands disposed about a head pulley 14 provided with a plurality of flanges which cause the belts to track with a predetermined spacing. Head pulley 14 is rotatably mounted on a frame 16 including a pair of substantially parallel, spaced sidewalls 18 and 18'. This construction as so far discussed of scraper 10 is conventional, and forms the upper, discharge portion or end of a cotton gleaner or scraper operating on the principle as disclosed in U.S. Pat. No. 2,670,584, issued Mar. 2, 1954 to W. E. Rood, Jr. et al. Further, while cotton scraper 10 is shown as terminating in a belt 12 disposed on a head pulley 14, it is to be understood that even those models of such cotton scrapers that employ drag chains (not shown) and the like can be employed with an attachment 20 according to the present invention. This attachment 20 is mounted on frame 16 of scraper 10 adjacent head pulley 14, and includes a separator assembly 22 which receives scrap cotton, dirt and debris or trash downwardly under the force of gravity from belt 12 and separates the dirt and trash from the cotton so as to clean the cotton, and a transfer assembly 24 shown mounted on frame 16 as by attachment to sidewalls 18 and 18', and disposed adjacent the separator assembly 22 for removing cotton from the assembly 22 and feeding same toward a storage bin (not shown) which can be disposed above the scraper 10 and supported by frame 16 thereof.
Separator assembly 22 includes a drum 26 rotatably mounted on frame 16 of scraper 10, and having an outer circumferential surface formed by a cylindrical wall 28 on which a plurality of sawteeth 30 are provided, which sawteeth 30 are arranged for grasping the scrap cotton fed to drum 26. The latter is journaled on sidewalls 18 and 18' as by shaft 32 disposed in bearings 34 and 34'. Rotation of shaft 32, and therefore drum 26, can be effected in a suitable manner, not shown, such as by connecting shaft 32 to the drive system of scraper 10.
Separator assembly 22 further includes a cage 36 arranged extending beneath drum 26 from adjacent the discharge end of scraper 10 substantially 180° from a point say 30° above a horizontal center line through shaft 32. This cage 36 acts to retain cotton (not shown) on the sawteeth 30 of drum 26, and includes a plurality of spaced, substantially parallel rods 38 curved around wall 28 of drum 26 and in spaced relation therefrom so as to permit the cotton to be retained by sawteeth 30. The rods 38, which function in the manner of a comb to permit dislodgment of dirt and trash from the cotton, are anchored on sidewalls 18 and 18' in a suitable manner, such as by the use of the illustrated perforated curved rails 40 and 40' attached to the inner surface of the associated walls 18 and 18'.
Cage 36 further includes a pipe 42 mounted on sidewalls 18, 18' and disposed extending between same so as to be adjacent an end one of the rods 38 and between such one of the rods 38 and head pulley 14. This pipe 42 has a diameter larger than a diameter of rods 38, and is arranged for guiding the cotton, dirt and trash from belt 12 onto drum 26 so that the cotton will pass between drum 26 and cage 36.
Transfer assembly 24 includes a fan 44 rotatably mounted adjacent drum 26 and the other of the end ones of the rods 38, that being the ones spaced furthest from head pulley 14, for removing cotton from sawteeth 30 of drum 26. The latter is disposed between fan 44, which functions as a doffer, and pipe 42 of cage 36.
Fan 44 includes a plurality of blades, with four perpendicularly extending blades being shown, which blades are affixed to a shaft 48 journaled in the sidewalls of a housing 50. This housing 50 is mounted on scraper 10 and includes a substantially horizontal surface 52 arranged above fan 44 for diverting the cotton downwardly through a chute 54 and into a blower 56 which can carry the cleaned cotton in a conventional manner upwardly to a holding bin (not shown) or similar shown mounted overhead of the scraper 10. Housing 50 is itself attached to frame 16 of scraper 10 as by the cantilever mounted brackets 58 and 58' attached to respective sidewalls 18 and 18'.
A screen 60, or similar dividing wall structure, is advantageously disposed extending from the portion of housing 50 closest to wall 28 of drum 46 for cooperating with fan 44 during removal of cotton from drum 26, and also for preventing any cotton not removed from drum 26 by fan 44 from being thrown away from separator assembly 22.
In operation, attachment 20 receives cotton, dirt and trash from belt 12 over head pulley 14, with the pipe 42 directing the material against the wall 28 of drum 26. The cotton will be grasped by sawteeth 30 while the dirt and trash will be knocked from the cotton by the combing action of cage 36, and permitted to fall through the gaps in cage 36 formed by the spacing between the rods 38. The now clean cotton will be brought around to fan 44 which acts to doff the cotton from sawteeth 30, and simultaneously create an air flow current due to rotation of blades 46 which causes the cotton to be directed downwardly due to the presence of wall 52, and to pass downwardly through chute 54 and into blower 56.
As can be readily understood from the above description and from the drawings, a cotton cleaning attachment according to the present invention permits existing cotton scrapers to be updated and to remain competitive with newer scrapers. Further, a cotton cleaner construction according to the present invention can be employed with newly constructed cotton scrapers as an integral part thereof so as to add an efficient cleaning capability to the scraper.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | A cotton cleaning attachment for a cotton scraper has a separator section mountable at a discharge end of a conventional scraper so as to receive scrap cotton, dirt and debris downwardly under the force of gravity from the discharge end of the scraper and separating the dirt and debris from the cotton. A transfer section, also mountable on the scraper and disposed downstream of the separator section, removes the cleaned cotton from the separator section, and causes the cotton to be fed to a subsequent stage of handling for further processing. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a freezing apparatus and, more particularly, to a novel improvement for increasing the freezing efficiency of a rotary compressor employed in the freezing apparatus.
2. Description of the Prior Art
Heretofore, reciprocating compressors were generally used in freezing units such as refrigerators or ice making machines. Recently, however, the use of rotary compressors has also been suggested as a way to save space in such devices.
It is generally known that, in a rotary compressor, the inside of the shell thereof is maintained at a relatively high pressure, so that the lubricating oil is charged at the high pressure side, and that, when the compressor is at a standstill, the refrigerant is mixed into the compressor oil. When the compressor is started with the refrigerant thus mixed into the oil, the refrigerant remains in the oil since the pressure in the oil chamber of the compressor is not lowered contrary to conventional reciprocating compressors. The result is that a shortage in the amount of refrigerant circulated through the refrigerant system occurs and increases in pressure at the high pressure side are not achieved smoothly. The effect of the shortage of refrigerant is more pronounced in a compressor charged with only a limited amount of refrigerant. Thus, since it is difficult to increase the pressure at the high pressure side in this manner, the pressure at the low pressure side becomes extremely low and a vacuum running phenomenon occurs in which the amount of the refrigerant in circulation is significantly reduced.
One of the reasons why the pressure increase at the high pressure side of the compressor is retarded is that the compressor at ambient temperature acts to cool the refrigerant due to its large thermal capacity and because heat radiation from the shell surface is also considerable due to the fact that the higher pressure side is in the compressor shell.
As a result of the above described phenomenon, the cooling properties at the beginning of the compressor starting operation will be lowered especially at lower ambient temperatures. This causes a refrigerating or ice making operation to be continued for an extended time, so that energy loss is correspondingly increased. For example, when the ice making machine performs the ice making operation in the above-described condition, the shape of the ice product(s) formed on the freezing mold at the inlet side of the evaporator may differ considerably from that of the ice products at the outlet side of the evaporator. The reason for this is that the pressure at the low pressure side becomes unusually low from the time the ice starts, the temperature at the inlet of the evaporator or the vaporization temperature being extremely low, and the temperature at the outlet side not being significantly lowered, thus resulting in an undesirable temperature balance between the inlet and the outlet of the evaporator.
The above-described phenomenon will become more pronounced when a lower ambient temperature prevails about the ice making machine. However, the same phenomenon occurs from time to time at a room temperature of about 10° C., which temperature is in excess of the sensing temperature (4° C. to 8° C.) of the defrosting or harvesting completion sensor thermostat so far used as means for sensing the completion of the harvesting cycle. The above-described problem, due to the undesirable temperature balance, cannot be solved even when the harvesting cycle start is controlled by a conventional control system. That is, when the harvesting thermostat is set to a higher temperature, the harvesting operation is protracted even during normal operation thus causing a loss in time. On the other hand, the pressure at the low pressure side during harvesting may be occasionally increased to an unusual value so that problems with respect to the durability of the compressor occur.
An advantageous feature of the rotary compressor is that it is lighter and more compact than a reciprocating compressor. However, its small thermal capacity resulting from its lightness proves to be a disadvantage when employed in an ice making machine using hot gas for defrosting. More specifically, during the defrosting cycle of the ice making machine, the ice formed by an evaporator is detached from the freezing mold by heating. During this defrosting cycle, the refrigerant gas is condensed and turned into a refrigerant liquid which is sucked in a large quantity into the compressor resulting in the cooling of the compressor. The rotary compressor having a smaller thermal capacity than the conventional reciprocating compressor is cooled more quickly than the reciprocating compressor. This indicates that the rotary compressor has an extremely low hot gas effectiveness as compared to the reciprocating compressor thus markedly affecting the defrosting ability at the lower temperature of the rotary compressor.
SUMMARY OF THE INVENTION
It is a principal object of the present invention to provide a freezing apparatus free of the aforementioned deficiencies of the prior-art apparatus.
It is another object of the present invention to provide a freezing apparatus exhibiting an improved cooling performance at the initial stage of the freezing operation.
It is a further object of the present invention to provide an ice making machine wherein the shape of the ice products is not markedly different at the inlet and outlet sides of the evaporator at the initial ice making cycle at lower temperatures, and wherein the initial ice making cycle may be terminated within a reasonably shorter time interval to thus improve the energy efficiency thereof.
According to the present invention, there is provided a freezing apparatus comprising a closed loop freezing circuit including a compressor having a refrigerant outlet and a refrigerant inlet, said closed loop circuit also including a condenser, expansion means and an evaporator disposed sequentially from said refrigerant outlet towards said refrigerant inlet, and a bypass conduit having one end connected to said closed loop circuit between the outlet side of said compressor and the inlet side of said condenser and having the other end connected to said closed loop circuit between the outlet side of said expansion means and the inlet side of said evaporator, said bypass conduit including first valve means, characterized in that the freezing apparatus further comprises a sensor for sensing the temperature or the pressure of the refrigerant in said closed loop circuit, and control means connected to said sensor to control the opening and closing of said first valve means in said bypass conduit in such a manner that, when the temperature or the pressure sensed by the sensor is below a prescribed value, the cooling operation of the freezing apparatus is effected only after the first valve means in said bypass conduit is opened and the compressor is actuated for elevating its temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
In the course of the following detailed description, reference will be made to the attached drawings in which the same reference numerals denote the same or similar parts in the several figures and in which:
FIG. 1 is a diagrammatic view showing a freezing circuit of the freezing apparatus according to a first embodiment of the present invention;
FIG. 2 is a connection diagram of the freezing circuit shown in FIG. 1;
FIG. 3 is a diagrammatic view showing a freezing circuit of the freezing apparatus according to a third embodiment; and
FIG. 4 is a diagrammatic view showing a freezing circuit of the freezing apparatus according to a fourth embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, and more particularly to FIG. 1, there is shown a freezing circuit according to a preferred embodiment of a freezing apparatus using a well-known rotary compressor, and FIG. 2 shows its control circuit. The numeral 1 denotes the rotary compressor having an insulating layer 1a on its outer surface. The compressor 1 has its outlet side 1b connected through a first pipe section 2 to a condenser 3 associated with a cooling fan 4 while the condenser 3 is connected through a capillary 5 and an evaporator 6 to an inlet side 1C of the compressor 1 by way of a second pipe section 7. If necessary, a well-known accumulator, not shown, may be provided at the inlet side of the compressor 1. The compressor 1, condenser 3, capillary 5 and the evaporator 6 are connected in sequentially in this order to comprise a closed loop circuit through which the freezing medium or refrigerant circulates, via the first and second pipe sections 2 and 7, in a direction of freezing medium flow through these sections.
A hot gas conduit 12 having a hot gas valve 11 has one end connected to a junction 10 provided in the first pipe section 2 between the output side 1b of the compressor 1 and the inlet side of the condenser 3. The hot gas conduit 12 has its other end connected to the second pipe section 7 between the output side of the capillary 5 and the inlet side of the evaporator 6. This hot gas conduit 12 comprises a bypass circuit 13 for supplying the freezing medium exiting from the compressor 1 directly to the evaporator 6.
A well-known type sensor 8 is provided in the first high pressure pipe section 2 upstream of the junction 10 with respect to the direction of the flow of the freezing medium and in the vicinity of the outlet side 1b, and the sensor 8 is connected to a switch 9 that may be a thermostat, an electronic temperature switch or a pressure switch. This sensor 8 senses the temperature or the pressure of the gaseous freezing medium and the switch 9 is actuated depending upon the sensed value of the temperature or pressure for controlling the hot gas valve 11, as described later.
The switch 9 is provided in a control circuit 14 shown in FIG. 2 and has first and second contacts 9a and 9b. The first contact 9a of the switch 9 is connected to a well-known type controller 15 for an ice making machine, and is also connected to a normally open contact 15a and a normally closed contact 15b, both being controlled by the controller 15. The contact 15a is serially connected to the hot gas valve 11, while the contact 15b is serially connected to the cooling fan 4. The second contact 9b of the switch 9 is serially connected to the hot gas valve 11 while the compressor 1 is connected to an electrical power source by way of an ice storage switch 16 sensing the quantity of ice contained in an ice stocker of the ice making machine, not shown.
During operation, when the ice storage switch 16 senses that the ice quantity in the ice stocker falls short of a prescribed amount, the switch 16 is turned on, so that the compressor 1 begins operating. The operation of the compressor is continued until the ice storage switch 16 is turned off. When the temperature and/or the pressure of the freezing medium as sensed by the sensor 8 associated with the switch 9 is in excess of a predetermined value, for example a temperature of 50° C. to 60° C., the second contact 9b is turned off to close the hot gas valve 11, while the first contact 9a is turned on to supply current to the controller 15 of the ice making machine, so that the usual freezing cycle is continued. However, when the temperature or the pressure sensed by the sensor 8 is lower than the preset value, the hot gas valve 11 is opened to open the first bypass circuit 13 so that the operation is switched to a bypass operation in which the hot gas is supplied from the compressor 1 to the evaporator 6 through the hot gas valve 11.
During this bypass operation, which is a hot gas cycle operation for the freezer and a defrosting or harvesting cycle operation for the ice making machine, the cooling fan 4 adapted to cool the condenser 3 is at a standstill. It is noted that, during the bypass operation, the compressor 1 as a whole becomes heated due to the heat from the compressor motor and due to the compression process of the freezing gas, and therefore the temperature of the compressor 1 is effectively increased, this increase being prolonged by the thermal insulation of the insulator 1a. The reason for this is that, since the hot gas valve 11 is now opened, the quantity of the cooling medium flowing through the bypass is larger than that when flowing in the capillary 5 so that the work load of the compressor 1 is also increased.
Hence, with the increase in the temperature of the compressor 1, the temperature or the pressure of the gaseous freezing medium is increased. When the temperature or the pressure sensed by the sensor 8 exceeds the prescribed value, the first and second contacts 9a, 9b of the switch 9 are turned on and off, respectively, for reinitiating the freezing cycle. At the time of initiation of the freezing cycle, the freezing medium is at its normal elevated pressure, so that ice having the desired shape may be produced right at the beginning of the freezing cycle.
Although the sensor is provided in the present embodiment at the high pressure side of the freezing circuit, a similar effect may be attained when the sensor is provided at the low pressure side for sensing the temperature or pressure of the freezing medium flowing through the circuit.
FIG. 3 shows a further modification of the present invention. The present modification is also similar to the embodiment shown in FIG. 1 except that a well-known three-way valve 20 is used instead of the hot gas valve 11, which is provided at the junction 10 between the first pipe section 2 and the bypass conduit 12. When one of the flow channels of the three-way valve 20 is opened for establishing communication between the outlet side 1b of the compressor 1 and the bypass conduit 12, the other flow channel is closed for interrupting communication of the gaseous refrigerant or freezing medium from the compressor 1 towards the condenser 3. In the reverse case, the other flow channel is opened. In the present embodiment, the flow of the refrigerant gas into the condenser 3, where the volume of heat radiation is at the maximum at the high pressure side of the freezing device, is inhibited during the bypass operation, the refrigerant gas being liquefied in the condenser 3 when the pressure or the temperature in the condenser 3 is lower than the saturation pressure or temperature of the refrigerant. Thus, any remnant refrigerant in a portion of the first piping section 2 downstream of the condenser 3 and the three-way valve 20 is supplied to the evaporator 6 through capillary 5, such that almost all of the refrigerant may be utilized for the bypass operation, resulting in that the time necessary for elevating the temperature of the compressor 1 is further reduced. It is therefore possible to compensate for the lesser heat volume of the compressor while avoiding situations such as those resulting in incapacitated harvesting during the normal operating cycle, the prolongation of the harvesting time with resulting over-melting of ice products, or excess energy consumption.
FIG. 4 shows a further modification of the present invention. The present modification differs from the embodiment shown in FIG. 1 only in that a separate valve 21 is provided in the first pipe section 2 downstream of the junction 10. The valve 21 is closed and opened when the hot gas valve 11 is opened and closed, respectively, so that the operation is similar to that of the embodiment shown in FIG. 3.
With the above-described freezing apparatus making use of the rotary compressor according to the present invention, the compressor is heated rapidly even when the compressor is at ambient temperature and it is only after the shell temperature is increased that the freezing apparatus performs the ice making operation. The result is that higher pressure is substantially equivalent to the pressure during the rated operation thereof, while the lower pressure is not lowered excessively at the time of initiation of the freezing operation. With an ice making machine employing the present invention, the ice formed on the freezing plate has the same shape at both the inlet side and the outlet side of the evaporator so that ice products having a uniform shape and hence, a higher commercial value, may be produced within a normal ice making time from the first freezing cycle so that energy efficiency is improved. With a refrigerator, air conditioner or a vehicle air conditioner in which the teachings of the present invention are incorporated, the cooling effect is markedly improved due to the improved dehumidification, de-frosting or cooling at the initiation of the operation.
While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof. | A refrigerating apparatus includes a compressor, a condenser, a capillary and an evaporator. A bypass conduit with a valve is arranged so that the refrigerant discharged from the compressor will bypass at least the condenser and the capillary so as to return to the inlet side of the compressor. The pressure or the temperature of the refrigerant in the apparatus is sensed by a sensor. When the sensed value is less than a prescribed value, the valve is opened to return the hot gas to the compressor. The compressor is driven for elevating its temperature. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application is a division of U.S. patent application Ser. No. 09/821,240, filed on Mar. 29, 2001, which is a division of U.S. patent application Ser. No. 09/350,601, filed on Jul. 9, 1999, now issued as U.S. Pat. No. 6,240,622, the specifications of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates to inductors, and more particularly, it relates to inductors used with integrated circuits.
BACKGROUND OF THE INVENTION
[0003] Inductors are used in a wide range of signal processing systems and circuits. For example, inductors are used in communication systems, radar systems, television systems, highpass filters, tank circuits, and butterworth filters.
[0004] As electronic signal processing systems have become more highly integrated and miniaturized, effectively signal processing systems on a chip, system engineers have sought to eliminate the use of large, auxiliary components, such as inductors. When unable to eliminate inductors in their designs, engineers have sought ways to reduce the size of the inductors that they do use.
[0005] Simulating inductors using active circuits, which are easily miniaturized, is one approach to eliminating the use of actual inductors in signal processing systems. Unfortunately, simulated inductor circuits tend to exhibit high parasitic effects, and often generate more noise than circuits constructed using actual inductors.
[0006] Inductors are miniaturized for use in compact communication systems, such as cell phones and modems, by fabricating spiral inductors on the same substrate as the integrated circuit to which they are coupled using integrated circuit manufacturing techniques. Unfortunately, spiral inductors take up a disproportionately large share of the available surface area on an integrated circuit substrate.
[0007] For these and other reasons there is a need for the present invention.
SUMMARY OF THE INVENTION
[0008] The above mentioned problems and other problems are addressed by the present invention and will be understood by one skilled in the art upon reading and studying the following specification. An integrated circuit inductor compatible with integrated circuit manufacturing techniques is disclosed.
[0009] In one embodiment, an inductor capable of being fabricated from a plurality of conductive segments and interwoven with a substrate is disclosed. In an alternate embodiment, a sense coil capable of measuring the magnetic field or flux produced by an inductor comprised of a plurality of conductive segments and fabricated on the same substrate as the inductor is disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1A is a cutaway view of some embodiments of an inductor of the present invention.
[0011] [0011]FIG. 1B is a top view of some embodiments of the inductor of FIG. 1A.
[0012] [0012]FIG. 1C is a side view of some embodiments of the inductor of FIG. 1A.
[0013] [0013]FIG. 2 is a cross-sectional side view of some embodiments of a highly conductive path including encapsulated magnetic material layers.
[0014] [0014]FIG. 3A is a perspective view of some embodiments of an inductor and a spiral sense inductor of the present invention.
[0015] [0015]FIG. 3B is a perspective view of some embodiments of an inductor and a non-spiral sense inductor of the present invention.
[0016] [0016]FIG. 4 is a cutaway perspective view of some embodiments of a triangular coil inductor of the present invention.
[0017] [0017]FIG. 5 is a top view of some embodiments of an inductor coupled circuit of the present invention.
[0018] [0018]FIG. 6 is diagram of a drill and a laser for perforating a substrate.
[0019] [0019]FIG. 7 is a block diagram of a computer system in which embodiments of the present invention can be practiced.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0020] In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that logical, mechanical and electrical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.
[0021] [0021]FIG. 1A is a cutaway view of some embodiments of inductor 100 of the present invention. Inductor 100 includes substrate 103 , a plurality of conductive segments 106 , a plurality of conductive segments 109 , and magnetic film layers 112 and 113 . The plurality of conductive segments 109 interconnect the plurality of conductive segments 106 to form highly conductive path 114 interwoven with substrate 103 . Magnetic film layers 112 and 113 are formed on substrate 103 in core area 115 of highly conductive path 114 .
[0022] Substrate 103 provides the structure in which highly conductive path 114 that constitutes an inductive coil is interwoven. Substrate 103 , in one embodiment, is fabricated from a crystalline material. In another embodiment, substrate 103 is fabricated from a single element doped or undoped semiconductor material, such as silicon or germanium. Alternatively, substrate 103 is fabricated from gallium arsenide, silicon carbide, or a partially magnetic material having a crystalline or amorphous structure. Substrate 103 is not limited to a single layer substrate. Multiple layer substrates, coated or partially coated substrates, and substrates having a plurality of coated surfaces are all suitable for use in connection with the present invention. The coatings include insulators, ferromagnetic materials, and magnetic oxides. Insulators protect the inductive coil and separate the electrically conductive inductive coil from other conductors, such as signal carrying circuit lines. Coatings and films of ferromagnetic materials, such as magnetic metals, alloys, and oxides, increase the inductance of the inductive coil.
[0023] Substrate 103 has a plurality of surfaces 118 . The plurality of surfaces 118 is not limited to oblique surfaces. In one embodiment, at least two of the plurality of surfaces 118 are parallel. In an alternate embodiment, a first pair of parallel surfaces are substantially perpendicular to a second pair of surfaces. In still another embodiment, the surfaces are planarized. Since most integrated circuit manufacturing processes are designed to work with substrates having a pair of relatively flat or planarized parallel surfaces, the use of parallel surfaces simplifies the manufacturing process for forming highly conductive path 114 of inductor 100 .
[0024] Substrate 103 has a plurality of holes, perforations, or other substrate subtending paths 121 that can be filled, plugged, partially filed, partially plugged, or lined with a conducting material. In FIG. 1A, substrate subtending paths 121 are filled by the plurality of conducting segments 106 . The shape of the perforations, holes, or other substrate subtending paths 121 is not limited to a particular shape. Circular, square, rectangular, and triangular shapes are all suitable for use in connection with the present invention. The plurality of holes, perforations, or other substrate subtending paths 121 , in one embodiment, are substantially parallel to each other and substantially perpendicular to substantially parallel surfaces of the substrate.
[0025] Highly conductive path 114 is interwoven with a single layer substrate or a multilayer substrate, such as substrate 103 in combination with magnetic film layers 112 and 113 , to form an inductive element that is at least partially embedded in the substrate. If the surface of the substrate is coated, for example with magnetic film 112 , then conductive path 114 is located at least partially above the coating, pierces the coated substrate, and is interlaced with the coated substrate.
[0026] Highly conductive path 114 has an inductance value and is in the shape of a coil. The shape of each loop of the coil interlaced with the substrate is not limited to a particular geometric shape. For example, circular, square, rectangular, and triangular loops are suitable for use in connection with the present invention.
[0027] Highly conductive path 114 , in one embodiment, intersects a plurality of substantially parallel surfaces and fills a plurality of substantially parallel holes. Highly conductive path 114 is formed from a plurality of interconnected conductive segments. The conductive segments, in one embodiment, are a pair of substantially parallel rows of conductive columns interconnected by a plurality of conductive segments to form a plurality of loops.
[0028] Highly conductive path 114 , in one embodiment, is fabricated from a metal conductor, such as aluminum, copper, or gold or an alloy of a such a metal conductor. Aluminum, copper, or gold, or an alloy is used to fill or partially fill the holes, perforations, or other paths subtending the substrate to form a plurality of conductive segments. Alternatively, a conductive material may be used to plug the holes, perforations, or other paths subtending the substrate to form a plurality of conductive segments. In general, higher conductivity materials are preferred to lower conductivity materials. In one embodiment, conductive path 114 is partially diffused into the substrate or partially diffused into the crystalline structure.
[0029] For a conductive path comprised of segments, each segment, in one embodiment, is fabricated from a different conductive material. An advantage of interconnecting segments fabricated from different conductive materials to form a conductive path is that the properties of the conductive path are easily tuned through the choice of the conductive materials. For example, the internal resistance of a conductive path is increased by selecting a material having a higher resistance for a segment than the average resistance in the rest of the path. In an alternate embodiment, two different conductive materials are selected for fabricating a conductive path. In this embodiment, materials are selected based on their compatibility with the available integrated circuit manufacturing processes. For example, if it is difficult to create a barrier layer where the conductive path pierces the substrate, then the conductive segments that pierce the substrate are fabricated from aluminum. Similarly, if it is relatively easy to create a barrier layer for conductive segments that interconnect the segments that pierce the substrate, then copper is used for these segments.
[0030] Highly conductive path 114 is comprised of two types of conductive segments. The first type includes segments subtending the substrate, such as conductive segments 106 . The second type includes segments formed on a surface of the substrate, such as conductive segments 109 . The second type of segment interconnects segments of the first type to form highly conductive path 114 . The mid-segment cross-sectional profile 124 of the first type of segment is not limited to a particular shape. Circular, square, rectangular, and triangular are all shapes suitable for use in connection with the present invention. The mid-segment cross-sectional profile 127 of the second type of segment is not limited to a particular shape. In one embodiment, the mid-segment cross-sectional profile is rectangular. The coil that results from forming the highly conductive path from the conductive segments and interweaving the highly conductive path with the substrate is capable of producing a reinforcing magnetic field or flux in the substrate material occupying the core area of the coil and in any coating deposited on the surfaces of the substrate.
[0031] [0031]FIG. 1B is a top view of FIG. 1A with magnetic film 112 formed on substrate 103 between conductive segments 109 and the surface of substrate 103 . Magnetic film 112 coats or partially coats the surface of substrate 103 . In one embodiment, magnetic film 112 is a magnetic oxide. In an alternate embodiment, magnetic film 112 is one or more layers of a magnetic material in a plurality of layers formed on the surface of substrate 103 .
[0032] Magnetic film 112 is formed on substrate 103 to increase the inductance of highly conductive path 114 . Methods of preparing magnetic film 112 include evaporation, sputtering, chemical vapor deposition, laser ablation, and electrochemical deposition. In one embodiment, high coercivity gamma iron oxide films are deposited using chemical vapor pyrolysis. When deposited at above 500 degrees centigrade these films are magnetic gamma oxide. In an alternate embodiment, amorphous iron oxide films are prepared by the deposition of iron metal in an oxygen atmosphere (10 −4 torr) by evaporation. In another alternate embodiment, an iron-oxide film is prepared by reactive sputtering of an Fe target in Ar+O 2 atmosphere at a deposition rate of ten times higher than the conventional method. The resulting alpha iron oxide films are then converted to magnetic gamma type by reducing them in a hydrogen atmosphere.
[0033] [0033]FIG. 1C is a side view of some embodiments of the inductor of FIG. 1A including substrate 103 , the plurality of conductive segments 106 , the plurality of conductive segments 109 and magnetic films 112 and 113 .
[0034] [0034]FIG. 2 is a cross-sectional side view of some embodiments of highly conductive path 203 including encapsulated magnetic material layers 206 and 209 . Encapsulated magnetic material layers 206 and 209 , in one embodiment, are a nickel iron alloy deposited on a surface of substrate 212 . Formed on magnetic material layer layers 206 and 209 are insulating layers 215 and 218 and second insulating layers 221 and 224 which encapsulate highly conductive path 203 deposited on insulating layers 215 and 218 . Insulating layers 215 , 218 , 221 and 224 , in one embodiment are formed from an insulator, such as polyimide. In an alternate embodiment, insulating layers 215 , 218 , 221 , and 224 are an inorganic oxide, such as silicon dioxide or silicon nitride. The insulator may also partially line the holes, perforations, or other substrate subtending paths. The purpose of insulating layers 215 and 218 , which in one embodiment are dielectrics, is to electrically isolate the surface conducting segments of highly conductive path 203 from magnetic material layers 206 and 209 . The purpose of insulating layers 221 and 224 is to electrically isolate the highly conductive path 203 from any conducting layers deposited above the path 203 and to protect the path 203 from physical damage.
[0035] The field created by the conductive path is substantially parallel to the planarized surface and penetrates the coating. In one embodiment, the conductive path is operable for creating a magnetic field within the coating, but not above the coating. In an alternate embodiment, the conductive path is operable for creating a reinforcing magnetic field within the film and within the substrate.
[0036] [0036]FIG. 3A and FIG. 3B are perspective views of some embodiments of inductor 301 and sense inductors 304 and 307 of the present invention. In one embodiment, sense inductor 304 is a spiral coil and sense inductor 307 is a test inductor or sense coil embedded in the substrate. Sense inductors 304 and 307 are capable of detecting and measuring reinforcing magnetic field or flux 309 generated by inductor 301 , and of assisting in the calibration of inductor 301 . In one embodiment, sense inductor 304 is fabricated on one of the surfaces substantially perpendicular to the surfaces of the substrate having the conducting segments, so magnetic field or flux 309 generated by inductor 301 is substantially perpendicular to sense inductor 304 . Detachable test leads 310 and 313 in FIG. 3A and detachable test leads 316 and 319 in FIG. 3B are capable of coupling sense inductors 304 and 307 to sense or measurement circuits. When coupled to sense or measurement circuits, sense inductors 304 and 307 are decoupled from the sense or measurement circuits by severing test leads 310 , 313 , 316 , and 319 . In one embodiment, test leads 310 , 313 , 316 , and 316 are severed using a laser.
[0037] In accordance with the present invention, a current flows in inductor 301 and generates magnetic field or flux 309 . Magnetic field or flux 309 passes through sense inductor 304 or sense inductor 307 and induces a current in spiral sense inductor 304 or sense inductor 307 . The induced current can be detected, measured and used to deduce the inductance of inductor 301 .
[0038] [0038]FIG. 4 is a cutaway perspective view of some embodiments of triangular coil inductor 400 of the present invention. Triangular coil inductor 400 comprises substrate 403 and triangular coil 406 . An advantage of triangular coil inductor 400 is that it saves at least a process step over the previously described coil inductor. Triangular coil inductor 400 only requires the construction of three segments for each coil of inductor 400 , where the previously described inductor required the construction of four segments for each coil of the inductor.
[0039] [0039]FIG. 5 is a top view of some embodiments of an inductor coupled circuit 500 of the present invention. Inductor coupled circuit 500 comprises substrate 503 , coating 506 , coil 509 , and circuit or memory cells 512 . Coil 509 comprises a conductive path located at least partially above coating 506 and coupled to circuit or memory cells 512 . Coil 509 pierces substrate 503 , is interlaced with substrate 503 , and produces a magnetic field in coating 506 . In an alternate embodiment, coil 509 produces a magnetic field in coating 506 , but not above coating 506 . In one embodiment, substrate 503 is perforated with a plurality of substantially parallel perforations and is partially magnetic. In an alternate embodiment, substrate 503 is a substrate as described above in connection with FIG. 1. In another alternate embodiment, coating 506 is a magnetic film as described above in connection with FIG. 1. In another alternate embodiment, coil 509 , is a highly conductive path as described in connection with FIG. 1.
[0040] [0040]FIG. 6 is a diagram of a drill 603 and a laser 606 for perforating a substrate 609 . Substrate 609 has holes, perforations, or other substrate 609 subtending paths. In preparing substrate 609 , in one embodiment, a diamond tipped carbide drill is used bore holes or create perforations in substrate 609 . In an alternate embodiment, laser 606 is used to bore a plurality of holes in substrate 609 . In a preferred embodiment, holes, perforations, or other substrate 609 subtending paths are fabricated using a dry etching process.
[0041] [0041]FIG. 7 is a block diagram of a system level embodiment of the present invention. System 700 comprises processor 705 and memory device 710 , which includes memory circuits and cells, electronic circuits, electronic devices, and power supply circuits coupled to inductors of one or more of the types described above in conjunction with FIGS. 1 A- 5 . Memory device 710 comprises memory array 715 , address circuitry 720 , and read circuitry 730 , and is coupled to processor 705 by address bus 735 , data bus 740 , and control bus 745 . Processor 705 , through address bus 735 , data bus 740 , and control bus 745 communicates with memory device 710 . In a read operation initiated by processor 705 , address information, data information, and control information are provided to memory device 710 through busses 735 , 740 , and 745 . This information is decoded by addressing circuitry 720 , including a row decoder and a column decoder, and read circuitry 730 . Successful completion of the read operation results in information from memory array 715 being communicated to processor 705 over data bus 740 .
Conclusion
[0042] Embodiments of inductors and methods of fabricating inductors suitable for use with integrated circuits have been described. In one embodiment, an inductor having a highly conductive path fabricated from a plurality of conductive segments, and including coatings and films of ferromagnetic materials, such as magnetic metals, alloys, and oxides has been described. In another embodiment, an inductor capable of being fabricated from a plurality of conductors having different resistances has been described. In an alternative embodiment, an integrated test or calibration coil capable of being fabricated on the same substrate as an inductor and capable of facilitating the measurement of the magnetic field or flux generated by the inductor and capable of facilitating the calibration the inductor has been described.
[0043] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement which is calculated to achieve the same purpose may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. Therefore, it is manifestly intended that this invention be limited only by the claims and the equivalents thereof. | The invention relates to an inductor comprising a plurality of interconnected conductive segments interwoven with a substrate. The inductance of the inductor is increased through the use of coatings and films of ferromagnetic materials such as magnetic metals, alloys, and oxides. The inductor is compatible with integrated circuit manufacturing techniques and eliminates the need in many systems and circuits for large off chip inductors. A sense and measurement coil, which is fabricated on the same substrate as the inductor, provides the capability to measure the magnetic field or flux produced by the inductor. This on chip measurement capability supplies information that permits circuit engineers to design and fabricate on chip inductors to very tight tolerances. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to weighing scales and more particularly to scales of the beam balance type in which a scale beam is pivotably supported on a beam fulcrum post and a load-receiving platform and support therefor are pivotably carried by the scale beam or beams.
Weighing scales of the type to which this invention pertains are customarily constructed to possess a predetermined load capacity and are initially calibrated to zero through the use of counterweights which are suspended on the beam at some convenient and effective location. The load-receiving area of the weighing platform is given a predetermined and fixed shape and value. Although such scales can obviously be employed in the weighing of particulate and fibrous materials it has been found that when fibrous materials of low bulk density are weighed frequently strands or fibers drape over the periphery of the weighing platform and adversely affect the accuracy of the measurement. To the contrary, relatively high bulk density material present little or no problem in terms of the accuracy of the measurement since the center of gravity of such materials coincides substantially with the vertical or longitudinal axis of the weighing platform and its support as well as with the pivot axis on the scale beam. It is not possible with existing scales to modify the size of the weighing platform to eliminate the draping over of the low bulk density fibrous materials without dissassembly of the scale and replacement of the weighing platform. In such event it would also be necessary to recalibrate the scale to zero thereby requiring that the scale be shipped back to the manufacturer and entailing additional time and expense.
SUMMARY OF THE INVENTION
It is one object of this invention to provide an extension platform for a weighing scale which can be mounted atop the existing scale platform and which will increase the accuracy of the scale when used in the weighing of low bulk density fibrous materials.
It is another objcet of the invention to provide an extension platform for a weighing scale of the character stated which can be installed on the scale without the need to recalibrate the scale to zero.
It is yet another object of this invention to provide the combination of a weighing scale of the beam balance type and an extension platform releasably mountable on the original weighing platform whereby to assure the accuracy of the scale even in connection with the weighing of low bulk density fibrous materials and obviating the need for factory recalibration of the scale to zero.
Other objects and advantages of the invention will become readily apparent to persons versed in the art to which the invention pertains from the ensuing description of the invention.
According to the present invention there is provided an extension platform for a beam balance scale comprising a generally planar upper surface, a lower surface having a grid of reinforcing ribs formed thereon subdividing the lower surface into a plurality of compartments, and a seating projection depending from the lower surface configured and dimensioned to snap over the peripheral rim of the weighing platform of a beam balance scale of preselected size to be mounted thereon releasably.
According to the present invention there is also provided the combination of a beam balance scale having a base, a beam fulcrum post carried on the base, at least one beam balance mounted pivotably on said post, and a load-receiving weighing platform and support therefor pivotably carried by the beam balance and an extension platform for the weighing platform aforestated, such extension platform comprising a generally planar upper surface, a lower surface having a grid of reinforcing ribs formed thereon subdividing the lower surface into a plurality of comparyments, and a seating projection depending from the lower surface configured and dimensioned to snap over the peripheral rim of the weighing platform of the scale so as to releasably mount the extension platform thereon.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be more fully comprehended it will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a beam balance weighing scale and an extension platform therefor shown in position to be mounted upon the weighing platform of the scale;
FIG. 2 is a bottom plan view of the extension platform shown in FIG. 1;
FIG. 3 is an end elevational view, in cross-section, of the extension platform shown in FIG. 2 taken along line B--B thereof;
FIG. 4 is a perspective view of a balance weight to be used in conjunction with the extension platform of FIG. 2; and
FIG. 5 is a perspective view of a counterweight to be used with the scale shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings there is shown generally, as indicated by reference numeral 10, a weighing scale of the beam balance type. The scale includes a base 12 at one end of which a pedestal 16 projects upwardly and is provided with a reference mark to indicate the zero state of the scale. One or more beam balances 14 are mounted pivotably upon a fulcrum post 15, and a slidable weight 20 is carried by each of such beams as is known. In a triple beam scale one of the beams provides a range of up to 10 grams, a second of the beams up to 100 grams, and the third beam up to 500 grams. It will be understood, of course, that the capacity of the individual beams and their associated slidable weights as well as the total capacity of the scale is predetermined.
There is mounted pivotably on the beams, such as on an end extension thereof opposed to the end terminating adjacent pedestal 16, a support member 18 surmounted by a load-receiving platform 22. One or more post elements 23 may be provided on a header member 42 common to the beams 14, such post elements being able to accomodate counterweights thereon (not shown). The scale construction so described is conventional. The platform 22 is not readily removable for any purpose and, as will be appreciated, has pre-established dimensions so as to present an upper load-receiving area of predetermined size. One of the inherent deficiencies of scales of this type is the susceptibility to error when the weighing platform is subjected to a tilting action due to an offset in the load resting upon the platform. Because of the limited area available for deposit of fibrous low bulk density materials the platform is subjected to such eccentric loading conditions.
The improvement provided by this invention stems from the use of an extension platform 26 in cooperation with a counterweight 24 configured and dimensioned to be carried upon header member 25. The extension platform is desirably disc-shaped with an upper generally planer surface 27, a peripherally extending stiffening rim or flange 28, and an under or lower surface 31 which is subdivided into a plurality of compartments 36 by a grid of reinforcing ribs comprising one or more circular ribs 30, an inner seating projection 32 and radially extending ribs 34. It will be observed that the outer extremities of such radial ribs terminate in stiffening rim 28 to thereby afford optimum strength for the extension platform. The platform is shown as being disc-shaped; however, it will be understood that other shapes may be employed provided they are symmetrical so as not to create any unbalanced moment forces which would produce the imbalance discussed above and thereby contribute to the inaccuracy of the scale.
As may be seen from FIGS. 2, 3 and 4 of the drawings there is provided a balance weight 38 of such configuration and dimensions that it is positionable within a selected one of compartments 36. Preferably the balance weight is given overall dimensions such that it fits snugly within the selected compartment for securement therewithin as will be described. The balance weight is a member having a generally planar peripherally extending marginal section 50 which, as aforestated, is configured to complement the configuration of the compartments so as to facilitate positioning of the balance weight therewithin. A chamber or pocket 54 is formed inwardly of the marginal section 50 and is defined by a plurality of side walls 52 which are integral with the project substantially perpendicularly from the marginal section. In its preferred form the balance weight and the extension platform are molded as one piece components from the same type of synthetic plastics material, the reinforcing ribs being formed in situ during the molding step. A quantity of pellet-like elements 56 are positioned within the pocket of the balance weight during the zero calibrating procedure to be described. Once the specific compartment is selected for positioning of the balance weight, and the correct number of pellets placed within the pocket of the balance weight, the balance weight is mounted within the compartment and permanently secured therewithin in any conventional manner. Thus, a suitable adhesive may be employed or the marginal section may be heat-sealed to the overlying surface of the platform. FIG. 3 illustrates a portion of the platform with the balance weight in position in the compartment formed between a pair of adjacent radial ribs 34 and between seating projection 32 and outer concentric reinforcing rib 30.
Referring to FIG. 1 it will be seen that the ends of the beams 14 terminate in common header 42 and that a common beam extension 40 continues outwardly to terminate adjacent pedestal 16 with its zero reference marking constituted by the arrowhead in the upper region of the pedestal. In initially calibrating the scale for use with the extension platform counterweight 24 is mounted atop header 42 such that its elongated body 44 rests upon beam extension 40 and its end retainer head is disposed on the opposite side of header 42. A slot or recess is formed between the retainer head and body of the counterweight and the head and body are connected by a shank 46 which extends integrally therebetween. Once the counterweight is so positioned the extension platform 26 is placed upon weighing platform 22 of the scale and snapped in releasable mounted relation thereon. The platform is oriented azimuthally such that one of its compartments 36 straddles the longitudinal axis of the scale. The balance weight is placed upon the upper surface of the platform 26 in registry with the thus oriented compartment, and a sufficient quantity of pellets or like elements 56 are inserted into the pocket 54 of the balance weight until observation of the outer end of the beam indicates (in cooperation with the zero reference marking on pedestal 16) that the scale has been calibrated to zero. The balance weight is thereafter mounted within the compartment 36 so selected and secured permanently therewithin as described above. Thus, whenever the extension platform is to be employed it simply is positioned on the weighing platform 22 of the scale with the compartment 36 having the balance weight 38 therein oriented across the longitudinal axis of the scale as described and outwardly of support member 18. There is no need to effect any further calibration of the scale.
It scales of the type described there is conventionally provided a check rod which is connected pivotably between the depending support for the weighing platform and the lower section of the beam fulcrum post so as to form a parallelogram linkage. The provision of the extension platform with its balance weight and the counterweight for the end of the beam, i.e. counterweight 24, is believed to minimize any moment forces imposed on such linkage and thereby reduce the inherent inaccuracy of the scale when low bulk density fibrous materials are to be weighed which would ordinarily extend beyond the peripheral edge of the permanent platform of the scale, such overhang tending to result in an inaccurate reading.
Although the invention has been described in specific terms it will be understood that various changes may be made in size, shape, materials and in the arrangement of the components without departing from the spirit and scope of the invention as claimed. | An extension platform for a beam balance scale and the combination of such a platform with a beam balance scale. The extension platform includes a generally planar upper surface and a lower surface having a grid of reinforcing ribs formed thereon subdividing the lower surface into a plurality of compartments. The lower surface is given a seating projection which depends therefrom and is configured and dimensioned to snap in place over the peripheral rim of the load-receiving platform of a beam balance scale of preselected size. The beam balance scale is thus rendered more accurate when used in the weighing of fibrous low bulk density materials. | 6 |
TECHNICAL FIELD
The present invention relates to a technique that provides an organoiridium complex suitable as an organic electroluminescent (EL) element, and particularly relates to an organoiridium complex useful as a green to yellow emitting material.
BACKGROUND ART
Technical development of the organic electroluminescent (EL) element is expected as next-generation displays and lighting. The features have advantages of low energy consumption, being capable of making thinner, excellent response speed, being capable of clear image display in both dark and bright places, and the like.
The basic structure of the organic EL element is a sandwich-like structure in which an organic compound of sole layer or multiple layers is sandwiched by a pair of electrodes. Specifically, there is proposed an element having a structure which uses, as a main configuration, a sandwich structure of a cathode/electron transport layer/emission layer/positive hole transport layer/anode/glass substrate, and which is obtained by appropriately adding a positive hole (electron) injection layer, buffer layer, interlayer insulating film, and the like in order to further enhance the properties. The emission layer which is a center of the sandwich structure uses various emitting materials, and the properties of the emission layer are required to easily flow electrons and positive holes which are transported from the cathode and anode, to have excellent light emission efficiency, to be durable, and the like.
Because of those demanded properties, development of phosphorescent materials has been required instead of the fluorescent materials having been conventionally applied as the emitting materials for the organic EL element. Since a generation probability ratio of excited molecule of an excited singlet to that of an excited triplet is 1:3 in the organic EL element, the phosphorescent material which exhibits phosphorescence by transition from the excited triplet state to the ground state is focused on in contrast to the fluorescent material which emits light by transition from the excited singlet to the ground state. Various organometallic complexes have been developed as such phosphorescent materials, and for example, there has been proposed an organometallic complex, as represented by the following Formula, in which a ligand (C—N ligand) having a heterocyclic ring and a C—N structure, and a ligand such as β-diketone are coordinated with a metal atom such as platinum or iridium. Specifically, PTL 1 discloses an organoiridium complex having a ligand with two benzene rings (diphenyl diketone) as the β-diketone ligand (SO 2 , etc. in PTL 1). In addition, PTL 2 discloses an organoplatinum complex or the like having a ligand with two butoxy-substituted benzene rings (tetra-butoxydiphenyl diketone) as the β-diketone ligand (PTL 2, Formula [1-1]). The light emission efficiency of the organometallic complexes described in the aforementioned PTLs is enhanced by application of the ligands having benzene ring as the β-diketone ligand.
CITATION LIST
Patent Literature
PTL 1: Japanese Patent Laid-Open Publication No. 2005-35902
PTL 2: Japanese Patent Laid-Open Publication No. 2008-222635
SUMMARY OF INVENTION
Technical Problem
Incidentally, “current efficiency (cd/A)” and “quantum efficiency (%)” are known as a basis for evaluating the light emission efficiency of the organic EL element. The current efficiency exhibits a luminance (or light strength considering visibility) with respect to an amount of current per unit, whereas the quantum efficiency is a percentage of the number of photons capable of being taken out as light energy with respect to an electric power consumption (the number of the injected carriers). In the quantum efficiency, there can be eliminated a part of consumed power which cannot be emitted as light energy (for example, a part of loss due to resistance), of the consumed power. Therefore, when evaluating the light emission efficiency by the quantum efficiency rather than the current efficiency, it is possible to evaluate the light emission efficiency of the organic EL element as a value close to the actual efficiency. Under these circumstances, when considering the organometallic complexes described in PTLs 1 and 2, the complexes do not necessarily have high quantum efficiency although there has been examined the complexes having high current efficiencies as the light emission efficiency.
In addition, it is effective that the aforementioned quantum efficiency shows a high value in a polymer (solid) such as a thin film. The reason is that usually an organometallic complex is not introduced in a solution or solvent, but is doped in a polymer thin film and is utilized as a emission layer in implementation to the organic EL element. In this point, many of the organometallic complexes described in PTLs 1 and 2, etc. showed a quantum efficiency to a certain degree in the solution of the organic solvent and the like, but the quantum efficiency was lowered in the polymer (solid) such as a thin film in many cases, and thus those did not show a high quantum efficiency in the thin film.
Accordingly, the present invention is aimed at providing an organometallic complex that has high quantum efficiency even in a (polymer) thin film as a emitting material for the organic EL element, and particularly provides an organometallic complex which can produce an organic EL element having high quantum efficiency with respect to a green to yellow electroluminescence.
Solution to Problem
For solving the aforementioned problems, the present inventors have focused on an organoiridium complex having iridium as a center atom. Although platinum complexes have also been developed as the organometallic complexes as described in PTL 2, the platinum complex has a high flatness and has an unoccupied ligand in the platinum atom that is the center element, and thus energy loss is easily generated. Specifically, the platinum complex is affected by various interactions including: intermolecular interaction (so-called self-organization) such as association-excimer formation; interaction with a medium such as solvents or matrix (mother materials); furthermore, association with other coexisting molecules; and the like. On the other hand, in the organoiridium complex, since the three ligands have a steric conformation, the aforementioned various interactions as in the platinum complex are not generated, and the energy loss is not easily caused, and thus it is considered that a material having high quantum efficiency is easily obtained.
Moreover, with respect to the quantum efficiency, attention has been focused on a “photoluminescence (PL) quantum yield” of the emitting material which is one of the factors that determines the quantum efficiency. When the quantum efficiency is roughly divided into “external quantum efficiency” and “internal quantum efficiency”, this PL quantum yield is, as shown in the following equations, one of the factors that determine the internal quantum efficiency. High internal quantum efficiency is required for the emitting materials, and particularly, influences of “exciton generation efficiency” and “PL quantum yield” are large as the factor that determines the internal quantum efficiency. Among them, since the “exciton generation efficiency” is determined depending on the difference in a fluorescent material and a phosphorescent material, the height of the PL quantum yield is important in order to enhance the internal quantum efficiency. Note that carrier balance in the following equation is a factor determined by combination of the materials and element structure such as film thickness control.
[Quantum Efficiency]
External quantum efficiency=(Efficiency of light extraction)×Internal quantum efficiency
Internal quantum efficiency=(Exciton generation efficiency)×(PL quantum yield)×(Carrier balance)
Accordingly, the present inventors have intensively studied organoiridium complexes showing a high photoluminescence (PL) quantum yield particularly in the polymer thin film. In the way of the study, the inventors have focused on organoiridium complexes which generate so-called “rigidchromism” where the emitted light in the polymer thin film is changed to be different from the emitted light in a solvent of solution, and have found that some complexes which generate such a rigidchromism show a high photoluminescence quantum yield in the polymer thin film, and then have completed the present invention. Here, the “chromism” means a phenomenon that optical properties of a substance are changed reversibly by an external stimulation. The “rigidchromism” indicates the case that the external stimulation which induces the chromism depends on the kind of the medium molecule, and the color of the emitted light is changed depending on whether the medium molecule is solution or solid. On the basis of the above studies, the present inventors have completed the present invention as an organoiridium complex which generates the rigidchromism.
Namely, the present invention relates to an organoiridium complex for an organic electroluminescent element represented by the following Formula; wherein a C—N ligand including two atomic groups (A 1 , A 2 ), and a β-diketone ligand in line symmetry having two tert-butyl-substituted phenyl groups are coordinated with an iridium atom.
(In the aforementioned Formula, R 1 , R 2 , and R 3 are each a tert-butyl group or a hydrogen atom, and have at least one tert-butyl group; they may bond each other to thereby form a saturated hydrocarbon ring, when having two tert-butyl groups; A 1 and A 2 are each an unsaturated hydrocarbon ring, at least one is a single ring, and at least one is a heterocyclic ring.)
The primary feature of the present invention is that, while assuming that the β-diketone as a ligand has a phenyl group and is in line-symmetry, it further has tert-butyl group as a substituent. An organoiridium complex having such a β-diketone tends to have a high photoluminescence quantum yield. However, even in the organoiridium complex having such a tert-butyl group, when a surrounding medium molecule was a solid polymer thin film, the quantum efficiency was not always to be high. As a result of further study by the present inventors as to the organoiridium complex having a high photoluminescence quantum yield even in the polymer thin film, the present invention has been completed by employing the following structure as the C—N ligand. On the other hand, for the design of the structure of an organometallic complex in the conventional techniques, the C—N ligand may be optionally selected from many mentioned structures as long as the desired luminescent color (red, blue, green, etc.) can be emitted, mainly in consideration of the wavelength sift. Namely, in the conventional technique, only the structure of β-diketone was characterized with almost no limitation of the C—N ligand.
As explained above, according to the present invention, the aforementioned β-diketone ligand is employed and, at the same time, the C—N ligand is also limited to the ligand having the following structure. When providing the organoiridium complex having a high photoluminescence quantum yield even in the polymer thin film, the present inventors have thought that the reason why the structure of the C—N ligand is to be specified is that the light emitting excited state of the iridium complex having a high photoluminescence quantum yield in the thin film is based on the charge transfer transition from the O—O ligand to the C—N ligand, and the C—N ligand preferably has a structure having a high electron accepting property. Here, when the polarity of the iridium complex is different between ground state and excited state, it is one factor of rigidchromism that the energy level (band gap) ΔE varies by the influences of the surrounding medium molecule. And, when creating the excited state of a charge transfer type by the aforementioned electron accepting C—N ligand, the rigidchromism may be realized. As a result, the present inventors have thought that an organoiridium complex, which makes the photoluminescence quantum yield varying with ΔE in the thin film high, would be available.
From the above studies, the present inventors have completed the present invention which is an organoiridium complex having a high photoluminescence quantum yield particularly in the thin film by specifying not only the feature of the β-diketone ligand but also the kind of the structure of the C—N ligand. The rigidchromism occurred in the organoiridium complex of the present invention is that in a peak of emission spectrum, a wavelength (λ PL ) in the polymer thin film shifts more to the short wavelength side, than a wavelength (λ PL ) in an organic solvent. When the wavelength shift (Δλ PL ) due to this rigidchromism is 15 nm or more and 100 nm or less, the organoiridium complex tends to have a particularly high light emission quantum efficiency. Further, the Δλ PL is particularly preferably 25 nm or more and 60 nm or less.
Hereinafter, the organoiridium complex of the present invention will be explained in detail.
The organoiridium complex of the present invention is obtained by coordinating the two C—N ligands and the β-diketone with the trivalent iridium atom. The two C—N ligands have the same structure, and the β-diketone has the line-symmetrical structure. The specific structures of the C—N ligand and the β-diketone ligand will be explained below.
The β-diketone ligand applied to the present invention is the compound having two tert-butyl-substituted phenyl groups represented by the following Formula.
In the above Formula, R 1 , R 2 , and R 3 are each tert-butyl group or hydrogen atom. One phenyl group has at least one tert-butyl group, preferably two or more tert-butyl groups. The two tert-butyl groups may bond each other to thereby form a saturated hydrocarbon ring.
The structure of the particularly preferable β-diketone ligand is shown below. In the following Formula, t-Bu represents tert-butyl group.
Next, the C—N ligand will be explained. A general formula of the C—N ligand applied to the present invention is represented by the following Formula.
In the above C—N ligand, the upper-side atomic group A 1 is the unsaturated hydrocarbon ring, and is preferably a 6-membered ring. The A 1 is preferably a single heterocyclic ring or a single benzene ring, and the heteroatom in the heterocyclic ring is preferably nitrogen. Further, A 1 may have any substituent in the side chain, and the substituent is preferably fluorine atom (F), trifluoro (—CF 3 ) group, or cyano (—CN) group.
Specifically, as the atomic group A 1 , any one shown in the following Formulae is preferable. In the following Formulae, the bonding site of A 1 to A 2 is designated by a downward dotted line.
The atomic group A 2 of the C—N ligand in the lower side is preferably a single heterocyclic ring, and the hetero atom is preferably nitrogen. Further, the A 2 may have any substituent in the side chain, and the preferred substituent includes fluorine atom (F), trifluoro (—CF 3 ) group, an alkyl group (—R, having 1 or more and 10 or less, preferably 1 or more and 4 or less carbons), an alkoxy group (—OR, having 1 or more and 4 or less carbons). Note that the A 2 is also an unsaturated hydrocarbon similar to the A 1 , and is preferably a 6-membered ring.
Specifically, as the atomic group A 2 , any one shown in the following Formulae is preferable. In the following Formula, the bonding site of A 2 to A 1 is designated by a downward dotted line.
In the aforementioned Formula, R is an alkyl group having 1 or more and 10 or less carbons.
The C—N ligand having the aforementioned atomic groups A 1 and A 2 includes the following compounds, for example.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
In the Formula, the symbol * shows the carbon which bonds to iridium.
The organoiridium complex of the present invention mentioned above has high light emission efficiency, and when 0.05 mmol/g doping is performed in a polymer thin film, the internal quantum efficiency φ PL is 0.45 or more. Therefore, the organoiridium complex is suitable for implementation to the organic electroluminescent element as the emission layer.
Furthermore, the organoiridium complex of the present invention tends to show a particularly high photoluminescence quantum yield in the polymer thin film in the range of the emission light color of yellow to green. Specifically, a light emission wavelength (λ PL ) in the polymer thin film is suitably 510 nm or more and 580 nm or less, particularly suitably 510 nm or more and 550 nm or less.
The organoiridium complex can be synthesized by reacting an iridium salt and a nitrogen-containing compound that constitutes the C—N ligand with each other by heating to thereby give a precursor, and then by reacting the precursor and a β-diketone compound with each other by heating. Alternatively, the organoiridium complex can also be synthesized by reacting a metal salt with a β-diketone compound, and then by reacting the resultant compound with a nitrogen-containing compound. The heating reaction for obtaining the precursor is preferably carried out at 80° C. or more and 130° C. or less for 12 hours or more and 24 hours or less, and the heating reaction with the β-diketone is preferably carried out at 60° C. or more and 130° C. or less for 0.5 hour or more and 12 hours or less. The reactions are preferably carried out in the presence of a solvent. The preferred iridium salt to be used in the aforementioned synthetic reaction is a chloride (IrCl 3 ). Furthermore, a hydrate of the chloride can be used as the form of use.
When the organoiridium complex mentioned above is applied to the organic EL element, the emission layer can be formed by a method such as spin coating method or vacuum deposition method. An element can be easily and inexpensively formed in the spin coating method.
Advantageous Effects of Invention
The organoiridium complex of the present invention is suitable as a emitting material of the organic EL element because of high photoluminescence quantum yield in the polymer thin film.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows the results of the light emission property of the organoiridium complex according to the embodiment.
FIG. 2 is a cross-sectional schematic view of the organic EL element produced in the embodiment.
FIG. 3A and FIG. 3B shows the results of the light emission property of the organic EL element according to the embodiment.
DESCRIPTION OF EMBODIMENTS
Hereinafter, there will be explained the preferred embodiments according to the present invention.
The following organoiridium complexes having the respective ligands were synthesized, and the emission spectrum of the obtained complexes was measured and the photoluminescence quantum yield was evaluated. X is a β-diketone ligand in the conventional example. Each iridium complex was synthesized by reacting an iridium salt and a nitrogen-containing compound to obtain a precursor, and then reacting the precursor and the β-diketone compound.
First, summary of the synthetic method of each of the aforementioned iridium complexes is explained. Firstly, each of the β-diketone compounds and each of the C—N ligands (1: 2′,6′-difluoro-2,3′-bipyridine), (2: 2-(3,5-bis(trifluoromethyl)phenyl)pyridine), (3: 2-(2,4-bis(trifluoromethyl)phenyl)pyridine) was synthesized. Then, each of the C—N ligands was reacted respectively with iridium chloride to synthesize precursors (1), (2) and (3). Each iridium complex described above was obtained by reacting each precursor with the β-diketone compound.
All of the starting materials, the reagents and solvents used for the synthesis were those having commercially available reagent grades without purification. Also with respect to dibenzoylmethane (β-diketone (X)), the commercially available compound was used as it was for the complex synthesis. The commercially available dehydrated THF was used as the dry THF as it was. In addition, a spherical silica gel (neutral) manufactured by KANTO CHEMICAL CO., INC. was used as a filler to be used for a column chromatography.
A proton nuclear magnetic resonance ( 1 H NMR) spectrum and a mass analysis (mass (MS) spectrum) were used for identification of the synthesized complexes. Jeol JNM-ECX400 spectrophotometer (400 MHz) or Jeol JNM-ECS400 spectrophotometer (400 MHz) was used for measurement of the 1 H NMR spectrum. The MS spectrum was measured by subjecting a sample ionized by an electro-spray ionization method (ESI method), or a matrix-assisted laser desorption ionization method (MALDI method) to the time-of-flight (TOF) type mass spectrometry (ESI-TOF-MS and MALDI-TOF-MS spectrum). Note that, in the MALDI-TOF-MS spectrum, α-cyano-4-hydroxycinnamic acid (CHCA) was used as a matrix. For the ESI-TOF-MS measurement, Jeol JML-T100LP mass spectrometry analyzer was used, and for the MALDI-TOF-MS measurement, Shimadzu-Kratos AXIMA-CFR PLUS TOF Mass mass spectrometry analyzer was used. Elemental analysis was performed by J-Science MICRO CORDER JM10 analysis machine by using acetanilide as a standard substance.
Synthesis of β-Diketone Compound (A)
After methyl 3,5-di(tert-butyl)benzoate and 3′,5′-di(tert-butyl)acetophenone were synthesized from 3,5-di(tert-butyl)benzoic acid, the β-diketone compound (A) was obtained by the synthetic reaction using these two compounds.
Synthesis of methyl 3,5-di(tert-butyl)benzoate
A concentrated sulfuric acid (0.9 mL) was dropped onto a mixture of 3,5-di(tert-butyl)benzoic acid (3.00 g, 12.8 mmol) and methanol (9 mL) under a nitrogen atmosphere at 0° C., followed by heating and refluxing the resulting substance for 1 hour with stirring. After being allowed to cool, chloroform (100 mL) was added, and further water (100 mL) was added, with the result that an organic layer was separated by shaking in a separating funnel. After repeating this procedure again, the separated organic layers were combined into one. After further washing the organic layer with a saturated aqueous sodium bicarbonate solution (50 mL) and a saturated saline (50 mL), the organic layer was then dried by addition of an appropriate amount of anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, methyl 3,5-di(tert-butyl)benzoate was obtained by distilling the solvent with an evaporator, and by drying the residue in a desiccator under a reduced pressure. The obtained compound was a white solid, and a yield was 92% (2.92 g, 11.8 mmol). The properties ( 1 H NMR, TOF MS) of the compound thus synthesized were as follows.
1 H NMR (CDCl 3 ): δ1.35 (s, 18H), 3.91 (s, 3H), 7.62 (t, J=2.0 Hz, 1H), 7.89 (d, J=2.0 Hz, 2H)
MALDI-TOF MS: m/z 249 ([M+H] + )
Synthesis of 3′,5′-di(tert-butyl)acetophenone
3,5′-di(tert-t-butyl)benzoic acid (3.00 g, 12.8 mmol) was added to a dry tetrahydrofuran (120 mL), and was cooled to 0° C. or less with stirring under a nitrogen atmosphere. 3.0 M methyl lithium solution in diethoxymethane (15 mL) was dropped onto the mixture, and after raising the temperature to a room temperature, was stirred for 2 hours. After adding a 6 M hydrochloric acid to the reaction mixture to be acidic, extraction with chloroform (100 mL×2) was carried out. The obtained organic layers were combined into one, and after washing with water (50 mL×2), a saturated aqueous sodium bicarbonate solution (50 mL) and a saturated saline (50 mL), an appropriate amount of anhydrous magnesium sulfate was added for drying. After removal of the magnesium sulfate by filtration, 3′,5′-di(tert-butyl)acetophenone was obtained by distilling the solvent with an evaporator, and by purifying the residue with a silica gel column chromatography (development solvent; chloroform). The obtained compound was a colorless liquid, and a yield was 75% (2.23 g, 9.60 mmol). The properties of the thus obtained compound were as follows.
1 H NMR (CDCl 3 ) δ1.37 (s, 18H), 2.60 (s, 3H), 7.64 (t, J=1.6 Hz, 1H), 7.80 (d, J=1.6 Hz, 2H)
MALDI-TOF MS: m/z 232 (M + )
Synthesis of β-Diketone Compound (A)
Methyl 3,5-di(tert-butyl)bezoate (2.92 g, 11.8 mmol) and sodium hydride (60% oil dispersion; 1.27 g, 31.8 mmol) were added to a dry THF (23 mL), and were stirred at a room temperature under a nitrogen atmosphere. Then, a solution obtained by dissolving the 3′,5′-di(tert-butyl)acetophenone (2.23 g, 9.60 mmol) in a dry THF (23 mL) was dropped onto the resultant substance for 30 minutes. Subsequently, the obtained reaction mixture was stirred for 24 hours at 60° C. After being allowed to cool, and after adding a 1 M hydrochloric acid to be acidic, extraction with chloroform (100 mL×2) was carried out. The obtained organic layers were combined into one, and after washing with water (50 mL×2), a saturated aqueous sodium bicarbonate solution (50 mL) and a saturated saline (50 mL), an appropriate amount of anhydrous magnesium sulfate was added for drying. After removal of the magnesium sulfate by filtration, 1,3-bis(3,5-di-(tert-butyl)phenyl) propane-1,3-dion(β-diketone A) was obtained by distilling the solvent with an evaporator, and by purifying the residue with a silica gel column chromatography (development solvent; chloroform). The obtained compound was an amber syrup substance, and a yield was 49% (2.12 g, 4.73 mmol). The properties of the thus obtained compound were as follows.
1 H NMR (CDCl 3 ) δ1.38 (s, 36H), 6.78 (s, 1H), 7.63 (t, J=2.0 Hz, 2H), 7.78 (d, J=2.0 Hz, 4H), 16.9 (brs, 1H)
MALDI-TOF MS: m/z 449 ([M+H] + )
Synthesis of β-Diketone Compound (B)
The β-diketone compound (B) was obtained by the synthetic reaction of 1,2,3,4-tetrahydro-1,1,4,4-tetramethylnaphthalene and malonyl chloride.
Synthesis of β-Diketone Compound (B)
1,2,3,4-tetrahydro-1,1,4,4-tetramethylnaphthalene (5.00 g, 26.6 mmol), malonyl chloride (1.35 g, 9.58 mmol) and aluminum chloride (5.51 g, 41.3 mmol) were added to carbon disulfide (27 mL), and were heated and stirred at 50° C. Next, a cooled 2 mol/L hydrochloric acid (27 mL) was added, and after transferring to a separating funnel, extraction was carried out with chloroform. The organic layer was further washed with water, and after distilling the solvent with an evaporator, a concentrated hydrochloric acid (3.5 mL) and chloroform (35 mL) were added, and were then heated and refluxed for 9 hours. After being allowed to cool, the mixture was transferred to a separatory funnel, and was washed with water and a saturated saline. The solvent was distilled off with a rotary evaporator after drying the organic layer by using an anhydrous magnesium sulfate. The β-diketone (B) was obtained in a yield of 39% (1.66 g, 3.74 mmol) by purifying the residue with a silica gel column chromatography (development solvent; ethyl acetate:hexane=1:2 (v/v)). The properties of the thus obtained compound were as follows.
1 H NMR (CDCl 3 ): δ1.30 (s, 12H), 1.34 (s, 12H), 1.71 (m, 8H), 6.76 (s, 1H), 7.40 (d, J=8.0 Hz, 2H), 7.68 (dd, J=8.0 and 2.0 Hz, 2H), 7.94 (d, J=2.0 Hz, 2H), 16.96 (brs, 1H)
MALDI-TOF MS: m/z 445 ([M+H] + )
Next, the C—N ligands (1) to (4) were synthesized according to the following manner.
Synthesis of C—N Ligand (1)
In accordance with the following formula, a C—N ligand (1) was obtained by reacting 2,6-difluoropyridineboronic acid with 2-bromopyridine. A mixture of 2,6-difluoropyridineboronic acid (2.08 g, 13.1 mmol), 2-bromopyridine (1.34 g, 8.48 mmol), THF (65 mL), water (26 mL), K 2 CO 3 (1.51 g, 10.9 mmol) and Pd(PPh 3 ) 4 (0.67 g, 0.580 mmol) was heated and refluxed for 16 hours under a nitrogen atmosphere. After being allowed to coot, the mixture was concentrated to approximately ⅓ in solution volume by a rotary evaporator, and then the obtained mixture was transferred to a separating funnel. After diluting with an appropriate amount of chloroform, the mixture was washed with water and a saturated saline, and the organic layer was dried on anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The C—N ligand (1) was obtained in a yield of 93% (1.51 g, 7.86 mmol) by purifying the residue with a silica gel chromatography (development solvent; ethyl acetate:hexane=1:3 (v/v)). The 1 H NMR property of the thus synthesized compound was as follows.
1 H NMR (CDCl 3 ): δ6.93 (dd, J=3.2, and 8.4 Hz, 1H), 7.20-7.32 (m, 1H), 7.68-7.86 (m, 2H), 8.56-8.73 (m, 2H)
Synthesis of C—N Ligand (2)
In accordance with the following formula, a C—N ligand (2) was obtained by reacting 3,5-bis(trifluoromethyl)phenylboronic acid with 2-iodopyridine. A mixture of 3,5-bis(trifluoromethyl)phenylboronic acid (2.00 g, 7.75 mmol), 2-iodopyridine (1.17 g, 5.71 mmol), THF (30 mL), water (10 mL), K 2 CO 3 (4.50 g, 32.6 mmol) and Pd(PPh 3 ) 4 (0.261 g, 0.226 mmol) was heated and refluxed for 48 hours under a nitrogen atmosphere. After being allowed to cool, the mixture was concentrated to approximately ⅓ in solution volume by a rotary evaporator, and then the obtained mixture was transferred to a separating funnel. After diluting with an appropriate amount of chloroform, the mixture was washed with water and a saturated saline, and the organic layer was dried on anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The C—N ligand (2) was obtained in a yield of 51% (0.850 g, 2.92 mmol) by purifying the residue with a silica gel chromatography (development solvent; chloroform). The 1 H NMR property of the thus synthesized compound was as follows.
1 H NMR (CDCl 3 ): δ7.34-7.38 (m, 1H), 7.81-7.87 (m, 2H), 7.92 (s, 1H), 8.49 (s, 2H), 8.76 (dt, J=2.2 and 5.0 Hz, 1H)
Synthesis of C—N Ligand (3)
In accordance with the following formula, a C—N ligand (3) was obtained by reacting 2,4-bis(trifluoromethyl)phenylboronic acid with 2-iodopyridine. A mixture of 2,4-bis(trifluoromethyl)phenylboronic acid (2.31 g, 8.96 mmol), 2-iodopyridine (1.16 g, 5.66 mmol), benzene (25 mL), ethanol (10 mL), K 2 CO 3 (7.31 g, 52.9 mmol) and PdCl 2 (PPh 3 ) 2 (0.383 g, 0.546 mmol) was heated and refluxed for 16 hours under a nitrogen atmosphere. After being allowed to cool, the reaction mixture was transferred to a separating funnel. After diluting with an appropriate amount of chloroform, the mixture was washed with water and a saturated saline, and the organic layer was dried on anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent was distilled off with a rotary evaporator. The C—N ligand (3) was obtained in a yield of 59% (0.978 g, 3.36 mmol) by purifying the residue with a silica gel chromatography (development solvent; chloroform). The 1 H NMR property of the thus synthesized compound was as follows.
1 H NMR (CDCl 3 ): δ7.33 (ddd, J=7.8, 7.7 and 1.1 Hz, 1H), 7.42 (d, J=7.8 Hz, 1H), 7.64 (d, J=7.7 Hz, 1H), 7.76 (ddd, J=7.7, 7.7 and 1.9 Hz, 1H), 7.86 (d, J=8.3 Hz, 1H), 8.01 (s, 1H)
Synthesis of C—N Ligand (4)
In accordance with the following formula, a C—N ligand (4) was obtained by reacting 2,4-difluoro-3-cyanophenylboronic acid with 2-iodopyridine. A mixture of 2,4-difluoropyridineboronic acid (0.976 g, 5.34 mmol), 2-iodopyridine (0.733 g, 3.58 mmol), benzene (15 mL), ethanol (6 mL), water (15 mL), K 2 CO 3 (4.56 g, 33.0 mmol) and Pd(PPh 3 ) 2 Cl 2 (0.215 g, 0.306 mmol) was heated and refluxed for 18 hours under a nitrogen atmosphere. After being allowed to cool, the mixture was concentrated to approximately ⅓ in solution volume by a rotary evaporator, and then the obtained mixture was transferred to a separating funnel. After diluting with an appropriate amount of chloroform, the mixture was washed with water and a saturated saline, and the organic layer was dried on anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The C—N ligand (4) was obtained in a yield of 80% (0.620 g, 2.87 mmol) by purifying the residue with a silica gel chromatography (development solvent; chloroform). The 1 H NMR property of the thus synthesized compound was as follows.
1 H NMR (CDCl 3 ): δ7.18 (ddd, J=1.4, 7.8 and 9.2 Hz, 1H), 7.33 (ddd, J=1.4, 5.0 and 7.3 Hz, 1H), 7.76-7.84 (m, 2H), 7.86 (td, J=6.4 and 8.7 Hz, 1H), 8.72 (m, 1H)
Precursor (1) to (3) were obtained by casing each of the thus synthesized C—N ligands and iridium chloride to react with each other.
Synthesis of Precursor (1)
In accordance with the following formula, a precursor (1) was obtained by casing the C—N ligand (1) and iridium chloride to react with each other. A mixture of 2′,6′-difluoro-2,3′-bipyridine (0.500 g, 2.60 mmol), iridium chloride trihydrate (0.442 g, 1.25 mmol), water (17 mL) and 2-ethoxyethanol (48 mL) was stirred for 12 hours at 100° C. After being allowed to cool, the mixture was concentrated by a rotary evaporator, water (50 mL) was added to the mixture. The resulting precipitant was recovered by suction filtration, and then the precursor (1) was obtained in a yield of 73% (0.580 g, 0.475 mmol) by washing with an appropriate amount of methanol. The thus obtained compound was an insoluble solid. Without further purification, the compound was used for the following synthesis of an iridium complex.
Synthesis of Precursor (2)
In accordance with the following formula, a precursor (2) was obtained by casing the C—N ligand (2) and iridium chloride to react with each other. A mixture of 2-(3,5-bis(trifluoromethyl)phenyl)pyridine (0.850 g, 2.92 mmol), iridium chloride trihydrate (0.430 g, 1.22 mmol), water (20 mL) and 2-ethoxyethanol (48 mL) was stirred for 12 hours at 100° C. After being allowed to cool, the mixture was concentrated by a rotary evaporator, water (50 mL) was added to the mixture. The resulting precipitant was recovered by suction filtration, and then the precursor (2) was obtained in a yield of 79% (0.930 g, 0.575 mmol) by washing with an appropriate amount of methanol. The thus obtained compound was an insoluble solid. Without further purification, the compound was used for the following synthesis of an iridium complex.
Synthesis of Precursor (3)
In accordance with the following formula, a precursor (3) was obtained by casing the C—N ligand (3) and iridium chloride to react with each other. A mixture of 2-(2,4-bis(trifluoromethyl)phenyl)pyridine (0.431 g, 1.48 mmol), iridium chloride trihydrate (0.264 g, 0.749 mmol), water (10 mL) and 2-ethoxyethanol (28 mL) was stirred for 12 hours at 100° C. After being allowed to cool, the mixture was concentrated by a rotary evaporator, water (30 mL) was added to the mixture. The resulting precipitant was recovered by suction filtration, and then the precursor (3) was obtained in a yield of 55% (0.329 g, 0.204 mmol) by washing with an appropriate amount of methanol. The thus obtained compound was an insoluble solid. Without further purification, the compound was used for the following synthesis of an iridium complex.
Synthesis of Precursor (4)
In accordance with the following formula, a precursor (4) was obtained by casing the C—N ligand (4) and iridium chloride to react with each other. A mixture of 2,6-difluoro-3-(pyridine-2-yl)benzonitrile (0.612 g, 2.83 mmol), iridium chloride trihydrate (0.492 g, 1.40 mmol), water (21 mL) and 2-ethoxyethanol (64 mL) was stirred for 25 hours at 100° C. After being allowed to cool, the mixture was concentrated by a rotary evaporator, water (50 mL) was added to the mixture. The resulting precipitant was recovered by suction filtration, and then the precursor (4) was obtained in a yield of 83% (0.762 g, 0.579 mmol) by washing with an appropriate amount of methanol. The thus obtained compound was an insoluble solid. Without further purification, the compound was used for the following synthesis of an iridium complex.
The thus synthesized precursors (1) to (4) and β-diketones (A), (B), and (X) were reacted with each other respectively to give respective iridium complexes.
Synthesis of Iridium Complex (1-A)
In accordance with the following formula, the iridium complex 1-A was obtained by reacting the precursor (1) and the β-diketone (A) with each other.
Synthesis of Iridium Complex (1-A)
The precursor (1) (0.244 g, 0.200 mmol), 1,3-bis(3,5-di(tert-butyl)phenyl)propane-1,3-dione (β-diketone (A)), (0.131 g, 0.292 mmol) and sodium carbonate (1.90 g, 17.9 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 30 minutes at 80° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 1-A was obtained in a yield of 25% (73.5 mg, 0.0719 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; methylene chloride), and by further performing recrystallization using acetonitrile. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.26 (s, 36H), 5.81 (t, J=1.8 Hz, 2H), 6.58 (s, 1H), 7.19-7.22 (m, 2H), 7.53 (m, 6H), 7.85-7.89 (m, 2H), 8.29 (d, J=7.6 Hz, 2H), 8.57 (dd, J=0.80 and 6.0 Hz, 2H)
ESI-TOF MS: m/z 1045 ([M+Na] + )
Anal. Calcd for C 51 H 53 F 4 IrN 4 O 2 : C, 59.92; H, 5.23; 5.48. Found: C, 60.10; H, 5.03; 5.50.
Synthesis of Iridium Complex (1-B)
In accordance with the following formula, the iridium complex 1-B was obtained by reacting the precursor (1) and the β-diketone (B) with each other.
Synthesis of Iridium Complex (1-B)
The precursor (1) (0.246 g, 0.201 mmol), β-diketone (B), (0.129 g, 0.290 mmol) and sodium carbonate (1.90 g, 17.9 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 30 minutes at 80° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 1-B was obtained in a yield of 25% (75.1 mg, 0.0738 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; methylene chloride), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.23 (s, 12H), 1.25 (s, 12H), 1.66 (s, 8H), 5.76 (s, 2H), 6.58 (s, 1H), 7.17-7.21 (m, 2H), 7.29 (d, J=8.0 Hz, 2H), 7.49-7.52 (m, 2H), 7.71 (d, J=2.0 Hz, 2H), 7.83-7.87 (m, 2H), 8.27 (d, J=8.8 Hz, 2H), 8.53 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 1041 ([M+Na] + )
Anal. Calcd for C 51 H 49 F 4 IrN 4 O 2 : C, 60.16; H, 4.85; 5.50. Found: C, 60.12; H, 4.61; 5.45.
Synthesis of Iridium Complex (1-X)
In accordance with the following formula, the iridium complex 1-X was obtained by reacting the precursor (1) and the β-diketone (X) with each other.
Synthesis of Iridium Complex (1-X)
The precursor (1) (0.500 g, 0.410 mmol), β-diketone (X), (0.435 g, 1.94 mmol) and sodium carbonate (0.389 g, 3.67 mmol) was added to 2-ethoxyethanol (77 mL), and the resulting mixture was stirred for 2 hours at 105° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 1-X was obtained in a yield of 38% (250 mg, 0.313 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; methylene chloride), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ5.75 (s, 2H), 6.66 (s, 1H), 7.23-7.25 (m, 2H), 7.35 (t, J=7.8 Hz, 4H), 7.45-7.47 (m, 2H), 7.77 (dd, J=1.2 and 7.8 Hz, 4H), 7.88 (t, J=7.8 Hz, 2H), 8.29 (d, J=8.0 Hz, 2H), 8.52 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 821 ([M+Na] + )
Anal. Calcd for C 35 H 21 F 4 IrN 4 O 2 : C, 52.69; H, 2.65; 7.02. Found: C, 52.92; H, 2.73; 7.01.
Synthesis of Iridium Complex (2-A)
In accordance with the following formula, the iridium complex 2-A was obtained by reacting the precursor (2) and the β-diketone (A) with each other.
Synthesis of Iridium Complex (2-A)
The precursor (2) (0.245 g, 0.152 mmol), 1,3-bis(3,5-di(tert-butyl)phenyl)propane-1,3-dione (β-diketone (A)), (0.129 g, 0.288 mmol) and sodium carbonate (1.90 g, 17.9 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 2 hours at 100° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 2-A was obtained in a yield of 5.8% (20.3 mg, 0.0166 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform:hexane=1:1 (v/v)), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.24 (s, 36H), 6.34 (s, 1H), 6.94-6.97 (m, 2H), 7.30 (d, J=1.6 Hz, 4H), 7.48 (t, J=1.6 Hz, 2H), 7.55 (brs, 2H), 7.78 (dt, J=1.6 and 7.8 Hz, 2H), 8.05 (d, J=7.6 Hz, 2H), 8.16 (brs, 2H), 8.27 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 1243 ([M+Na] + )
Anal. Calcd for C 57 H 55 F 12 IrN 2 O 2 : C, 56.10; H, 4.54; 2.30. Found: C, 55.93; H, 4.49; 2.26.
Synthesis of Iridium Complex (2-B)
In accordance with the following formula, the iridium complex 2-B was obtained by reacting the precursor (2) and the β-diketone (B) with each other.
Synthesis of Iridium Complex (2-B)
The precursor (2) (0.154 g, 0.0953 mmol), β-diketone (B), (0.200 g, 0.450 mmol) and sodium carbonate (0.0900 g, 0.849 mop was added to 2-ethoxyethanol (18 mL), and the resulting mixture was stirred for 3 hours at 105° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 2-B was obtained in a yield of 39% (90.0 mg, 0.0740 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.16 (s, 12H), 1.23 (s, 12H), 1.64 (s, 8H), 6.32 (s, 1H), 6.91-6.95 (m, 2H), 7.22 (d, J=7.8 Hz, 2H), 7.30 (dd, J=2.0 and 7.8 Hz, 2H), 7.43 (d, J=2.0 Hz, 2H), 7.55 (s, 2H), 7.73-7.78 (m, 2H), 8.01 (d, J=8.0 Hz, 2H), 8.16 (s, 2H), 8.22 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 1239 ([M+Na] + )
Anal. Calcd for C 57 H 51 F 12 IrN 2 O 2 : C, 56.29; H, 4.23; 2.30. Found: C, 56.60; H, 4.40; 2.26.
Synthesis of Iridium Complex (2-X)
In accordance with the following formula, the iridium complex 2-X was obtained by reacting the precursor (2) and the β-diketone (X) with each other.
Synthesis of Iridium Complex (2-X)
The precursor (2) (0.331 g, 0.205 mmol), β-diketone (X), (0.220 g, 0.981 mmol) and sodium carbonate (0.195 g, 1.84 mmol) was added to 2-ethoxyethanol (39 mL), and the resulting mixture was stirred for 3 hours at 105° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 2-X was obtained in a yield of 30% (120 mg, 0.121 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ6.43 (s, 1H), 6.94-6.98 (m, 2H), 7.29 (t, J=7.8 Hz, 4H), 7.41 (t, J=7.8 Hz, 2H), 7.55-7.57 (m, 6H), 7.74-7.78 (m, 2H), 8.00 (d, J=8.4 Hz, 2H), 8.13 (s, 2H), 8.21 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 1019 ([M+Na] + )
Anal. Calcd for C 41 H 23 F 12 IrN 2 O 2 .H 2 O: C, 48.57; H, 2.49; 2.76. Found: C, 48.76; H, 2.60; 2.67.
Synthesis of Iridium Complex (3-A)
In accordance with the following formula, the iridium complex 3-A was obtained by reacting the precursor (3) and the β-diketone (A) with each other.
Synthesis of Iridium Complex (3-A)
The precursor (3) (0.240 g, 0.149 mmol), 1,3-bis(3,5-di(tert-butyl)phenyl)propane-1,3-dione (β-diketone (A)), (0.129 g, 0.288 mmol) and sodium carbonate (1.91 g, 18.1 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 2 hours at 100° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 3-A was obtained in a yield of 44% (154 mg, 0.126 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform:hexane=1:1 (v/v)), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.25 (s, 36H), 6.53 (s, 1H), 6.70 (s, 2H), 7.20-7.24 (m, 2H), 7.44 (d, J=2.0 Hz, 4H), 7.50 (t, J=2.0 Hz, 2H), 7.54 (s, 2H), 7.86-7.91 (m, 2H), 8.44 (d, J=8.0 Hz, 2H), 8.67 (dd, J=1.4 and 5.8 Hz, 2H)
ESI-TOF MS: m/z 1243 ([M+Na] + )
Anal. Calcd for C 57 H 55 F 12 IrN 2 O 2 : C, 56.10; H, 4.54; 2.30. Found: C, 56.27; H, 4.74; 2.41.
Synthesis of Iridium Complex (3-B)
In accordance with the following formula, the iridium complex 3-B was obtained by reacting the precursor (3) and the β-diketone (B) with each other.
Synthesis of Iridium Complex (3-B)
The precursor (3) (0.241 g, 0.149 mmol), β-diketone (B), (0.129 g, 0.290 mmol) and sodium carbonate (1.90 g, 18.0 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 2 hours at 100° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 2-B was obtained in a yield of 17% (59.7 mg, 0.0491 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform:hexane=1:1 (v/v)), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.16 (s, 6H), 1.18 (s, 6H), 1.22 (s, 6H), 1.23 (s, 6H), 1.64 (s, 8H), 6.52 (s, 1H), 6.64 (s, 2H), 7.20 (t, J=6.0 Hz, 2H), 7.27 (d, J=7.8 Hz, 2H), 7.43 (dd, J=2.0 and 7.8 Hz, 2H), 7.53 (s, 2H), 7.61 (d, J=2.0 Hz, 2H), 7.83-7.88 (m, 2H), 8.41 (d, J=8.0 Hz, 2H), 8.63 (d, J=6.0 Hz, 2H)
ESI-TOF MS: m/z 1239 ([M+Na] + )
Anal. Calcd for C 57 H 51 F 12 IrN 2 O 2 : C, 56.29; H, 4.23; 2.30. Found: C, 56.30; H, 4.05; 2.28.
Synthesis of Iridium Complex (3-X)
In accordance with the following formula, the iridium complex 3-X was obtained by reacting the precursor (3) and the β-diketone (X) with each other.
Synthesis of Iridium Complex (3-X)
The precursor (3) (0.200 g, 0.124 mmol), β-diketone (X), (0.128 g, 0.571 mmol) and sodium carbonate (0.115 g, 1.09 mmol) was added to 2-ethoxyethanol (23 mL), and the resulting mixture was stirred for 3 hours at 105° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then chloroform was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous sodium sulfate. After removal of the sodium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 3-X was obtained in a yield of 10% (25.0 mg, 0.0251 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ6.60 (s, 2H), 6.61 (s, 1H), 7.21-7.24 (m, 2H), 7.32 (t, J=7.4 Hz, 4H), 7.44 (t, J=7.4 Hz, 2H), 7.54 (s, 2H), 7.72 (d, J=7.4 Hz, 4H), 7.85-7.90 (m, 2H), 8.41 (d, J=8.8 Hz, 2H), 8.64 (dd, J=0.8 and 5.8 Hz, 2H)
ESI-TOF MS: m/z 1019 ([M+Na] + )
Anal. Calcd for C 41 H 23 F 12 IrN 2 O 2 : C, 49.45; H, 2.33; 2.81. Found: C, 49.60; H, 2.70; 2.70.
Synthesis of Iridium Complex (4-A)
In accordance with the following formula, the iridium complex 4-A was obtained by reacting the precursor (4) and the β-diketone (A) with each other.
Synthesis of Iridium Complex (4-A)
The precursor (4) (0.243 g, 0.185 mmol), 1,3-bis(3,5-di(tert-butyl)phenyl)propane-1,3-dione (β-diketone (A)), (0.133 g, 0.296 mmol) and sodium carbonate (1.90 g, 17.9 mmol) was added to 2-ethoxyethanol (50 mL), and the resulting mixture was stirred for 2 hours at 100° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then ethyl acetate was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 4-A was obtained in a yield of 12% (0.0459 g, 0.0429 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; chloroform), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ 1.26 (s, 36H), 5.98 (d, J=8.6 Hz, 2H), 6.56 (s, 1H), 7.22 (td, J=1.4 and 5.9 Hz, 2H), 7.49 (d, J=1.8 Hz, 4H), 7.54 (t, J=1.8 Hz, 2H), 7.90 (td, J=1.4 and 8.2 Hz, 2H), 8.32 (d, J=8.2 Hz, 2H), 8.55 (dd, J=1.4 and 5.9 Hz, 2H)
ESI-TOF MS: m/z 1093 ([M+Na] + )
Anal. Calcd for C 55 H 53 F 4 IrN 4 O 2 : C, 61.72; H, 4.99; N, 5.23. Found: C, 61.72; H, 5.03; N, 5.23.
Synthesis of Iridium Complex (4-B)
In accordance with the following formula, the iridium complex 4-B was obtained by reacting the precursor (4) and the β-diketone (B) with each other.
Synthesis of Iridium Complex (4-B)
The precursor (4) (0.106 g, 0.0805 mmol), β-diketone (B), (0.0884 g, 0.199 mmol) and sodium carbonate (0.0531 g, 0.501 mmol) was added to 2-ethoxyethanol (25 mL), and the resulting mixture was stirred for 1 hour and 30 minutes at 40° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then methylene chloride was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 4-B was obtained in a yield of 22% (0.0378 g, 0.0355 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; methylene chloride), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ1.24 (m, 24H), 1.66 (m, 8H), 5.92 (d, J=8.6 Hz, 2H), 6.58 (s, 1H), 7.21-7.24 (m, 2H), 7.29 (d, J=8.6 Hz, 2H), 7.48 (dd, J=1.8 and 8.6 Hz, 2H), 7.69 (d, J=1.8 Hz, 2H), 7.86-7.90 (m, 2H), 8.30 (d, J=8.6 Hz, 2H), 8.50 (dd, J=1.4 and 5.9 Hz, 2H)
ESI-TOF MS: m/z 1089 ([M+Na] + )
Anal. Calcd for C 55 H 49 F 4 IrN 4 O 2 : C, 61.96; H, 4.63; N, 5.25. Found: C, 61.94; H, 4.59; N, 5.25.
Synthesis of Iridium Complex (4-X)
In accordance with the following formula, the iridium complex 4-X was obtained by reacting the precursor (4) and the β-diketone (X) with each other.
Synthesis of Iridium Complex (4-X)>
The precursor (4) (0.0980 g, 0.0745 mmol), β-diketone (X), (0.0496 g, 0.221 mmol) and sodium carbonate (0.0650 g, 0.613 mmol) was added to 2-ethoxyethanol (7 mL), and the resulting mixture was stirred for 30 minutes at 40° C. under a nitrogen atmosphere. After being allowed to cool, the solvent was distilled off by a rotary evaporator, and then methylene chloride was added to the residue. The obtained mixed solution was washed with water and a saturated saline, and was then dried by adding an appropriate amount of anhydrous magnesium sulfate. After removal of the magnesium sulfate by filtration, the solvent of the filtrate was distilled off with a rotary evaporator. The iridium complex 4-X was obtained in a yield of 21% (0.0254 g, 0.0300 mmol) by purifying the obtained residue with a silica gel column chromatography (development solvent; methylene chloride), and by further performing recrystallization using methanol. The properties of the thus synthesized compound were as follows.
1 H NMR (CDCl 3 ): δ5.91 (d, J=8.8 Hz, 2H), 6.65 (s, 1H), 7.26-7.28 (m, 2H), 7.35 (t, J=7.7 Hz, 4H), 7.45-7.49 (m, 2H), 7.75-7.77 (m, 4H), 7.90 (td, J=1.4 and 8.4 Hz, 2H), 8.32 (d, J=8.4 Hz, 2H), 8.49 (dd, J=1.4 and 5.6 Hz, 2H)
ESI-TOF MS: m/z 869 ([M+Na] + )
Anal. Calcd for C 39 H 21 F 4 IrN 4 O 2 : C, 55.38; H, 2.50; N, 6.62. Found: C, 55.38; H, 2.74; N, 6.74.
[Evaluation of Photoluminescence (PL) Spectrum and PL Quantum Yield]
The photoluminescence (PL) spectrum and the PL quantum yield φ PL of each iridium complex obtained above were measured. Fluorolog-3 spectrometer manufactured by HORIBA, Ltd. was used for measuring the PL spectrum. C9920-12 Quantum yield measuring machine manufactured by HAMAMATSU Photonics K.K. was used for measuring the PL quantum yield. The evaluation of these PL spectrum and PL quantum yield were conducted in a polymer thin film (polymethyl methacrylate, PMMA), as medium. Note that the solution sample sealed with argon gas was measured as a deoxidized solution, and the polymer thin film sample was measured under a nitrogen atmosphere. The polymer thin film sample was measured by 0.05 mmol/g (4 wt %) doping of each iridium complex into PMMA. The results are shown in the following Table.
TABLE 1
Wavelength
PL
λ PL
Quantum yield
(nm)
φ PL
1-A
537
0.58
2-A
545
0.52
3-A
545
0.49
4-A
543
0.45
1-B
537
0.62
2-B
548
0.47
3-B
548
0.68
4-B
537
0.53
1-X
550
0.23
2-X
561
0.17
From the above Table, the iridium complexes having the tert-butyl-substituted phenyl group as the β-diketone (1-A, 2-A, 3-A, 4-A, 1-B, 2-B, 3-B, 4-B) showed photoluminescence quantum yields higher than 0.45 in the polymer thin film.
Next, with respect to the iridium complexes 1-A, 2-A, 1-B, 2-B, the PL spectrum and PL quantum yield were evaluated in an organic solvent (dichloromethane (CH 2 Cl 2 )), as medium. The results are shown in the following Table and in FIG. 1 . In the following Table, the results in the polymer thin film are shown together, and also calculated values of difference (wavelength shift Δλ PL ) between the position of wavelength peak in the organic solvent and the position of wavelength peak in the polymer thin film are shown.
TABLE 2
In organic solvent
In polymer thin film
λ PL
λ PL
Wavelength shift
(nm)
φ PL
(nm)
φ PL
Δλ PL
1-A
573
0.19
537
0.58
36
2-A
595
0.11
545
0.52
50
1-B
567
0.28
537
0.62
30
2-B
596
0.18
548
0.47
48
From the above Table and FIG. 1 , with respect to the iridium complexes having the tert-butyl-substituted phenyl group as the β-diketone (1-A, 2-A, 1-B, 2-B), the rigidchromism was observed where the position of the wavelength peak in the polymer thin film shifted to the short wavelength side relative to the wavelength peak in an organic solvent. In the viewpoint of luminescent color, the light emission wavelength of yellowish green to orange in the organic solvent changed to the light emission wavelength of green to yellow in the polymer thin film.
From the aforementioned results, it has been found that the iridium complexes having the tert-butyl-substituted phenyl group as the β-diketone had the PL quantum yield φ PL of 0.45 or more when doping to the polymer thin film at a dose of 0.05 mmol, and showed the rigidchromism where the light emission wavelength in the polymer thin film shifted to the short wavelength side relative to the light emission wavelength in an organic solvent.
[Production and Property Evaluation of Organic EL Element]
The iridium complexes were used to produce the organic EL element (1) shown in FIG. 2 in the following procedures, and its properties were evaluated.
<Production of Organic EL Element>
(a) Formation of Hole Injection Layer (5)
An anode (2) was prepared by subjecting an ITO-glass substrate (manufactured by SANYO Vacuum Industries Co., Ltd., ITO, film thickness 150 nm) to patterning treatment and then by performing washing. Next, the ITO thin film was surface-treated by ozone. After the surface treatment, a hole injection layer (5) having a thickness of 40 nm was formed by rapid film formation of a hole injection material on the ITO film through the use of the spin coating method, and by baking at 120° C. for 1 hour. An electrically conductive polymer (P VP CH8000 manufactured by Heraeus Clevios) containing PEDOT and PSS was used as the hole injection material.
(b) Formation of Emission Layer (4)
An ink Ink (1-A) for the emission layer was prepared by dissolution of poly(9-vinylcarbasol) (PVCz, manufactured by Sigma-Aldrich, Number average molecular weight Mn, 25000-50000, purified by re-precipitating from THF-methanol), 2-(4-biphenilyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD) and the iridium complex 1-A in a dehydrated toluene, and by filtration with a membrane filter (0.2 μm Millex-FG manufactured by Merck Millipore Corporation). The concentrations of the PBD and the iridium complex to be doped to 1 g of PVCz were 850 μmol and 98 μmol, respectively, and 0.7 ml of the toluene was used to 10 mg of PVCz as a solvent for the ink. Through the use of the obtained ink (1-A) for the emission layer, a emission layer 4 having a thickness of 80 nm was formed on the hole injection layer (5) by film formation using the spin coating method, and then by baking at 120° C. for 1 hour.
(c) Formation of Electron Injection Layer (6) and Cathode (3)
A thin film of cesium fluoride (electron injection layer (6), thickness 1 nm) as the electron-injecting material was formed by the vacuum deposition, through the use of a shadow mask, and then, a thin film of aluminum (cathode (3), thickness 250 nm) was produced. At this time, the electron injection layer (6) and the cathode (3) were produced so that the area of the light-emitting portion was 10 mm 2 (2 mm×5 mm). In this way, the organic EL element EL(1-A) was completed.
<Production of Organic EL Element Used Each Iridium Complex as Emitting Material>
An ink Ink (2-A) for the emission layer was prepared by using the iridium complex 2-A instead of the iridium complex 1-A. An organic EL element EL(2-A) was obtained in the similar way to the above procedures except that the ink Ink (2-A) was used for the emission layer. The organic EL elements EL(3-A), EL(4-A), EL(1-B), EL(2-B), EL(3-B), EL(4-B), EL(1-X), EL(2-X), EL(3-X), EL(4-X) were also produced by using the complexes 3-A, 4-A, 1-B, 2-B, 3-B, 4-B, 1-X, 2-X, 3-X, 4-X instead of the complex 1-A.
<Evaluation of Organic EL Element Properties>
Samples for evaluating the organic EL properties were produced with the organic EL element obtained by the above steps sealed into a cavity glass by using an ultraviolet curable resin.
The organic EL element properties such as EL spectrum, maximum luminance L max (cd/m 2 ), maximum external quantum efficiency η ext.max (%), and CIE standard colorimetric system (x,y) were measured by a luminance goniophotometer (C-9920-11, manufactured by HAMAMATSU Photonics K.K.).
Table 2 shows the results of the peak wavelength λ EL (nm), the maximum luminance L max (cd/m 2 ), the maximum external quantum efficiency η ext.max (%), the maximum current efficiency η j,max (cd/A), the maximum power efficiency η p,max (Im/W), and CIE standard colorimetric system (x,y). The L max and η ext,max are shown along with the applied voltage (V) at the time of measurement in brackets. Note that the luminescence starting voltage V turn-on represents the voltage at which the luminance reaches 1 cd/m 2 .
Furthermore, FIG. 3A and FIG. 3B shows the electroluminescent (EL) spectrum of the organic EL element EL(1-A), EL(2-A), EL(3-A), EL(4-A), EL(1-B), EL(2-B), EL(3-B), EL(4-B), EL(1-X), EL(2-X), EL(3-X), EL(4-X). The EL spectrum was measured at the maximum luminance L max .
TABLE 3
Maximum
Maximum
Maximum
Maximum
external
current
power
Luminescence
luminance
quantum
efficiency
efficiency
starting
L max /
efficiency
η j, max /
η p, max /
voltage
cd m −2
η ext. max /%
cd A −1
lm W −1
λ EL /
CIE
Element
V turn-on /V
(@V)
(@V)
(@V)
(@V)
nm
(x, y)
EL (1-A)
4.0
6200
(14.0)
3.0
(8.5)
9.5
(8.5)
4.1
(7.0)
550
(0.43, 0.54)
EL (1-B)
4.5
4500
(15.0)
1.8
(8.0)
5.8
(6.5)
3.8
(4.5)
539
(0.42, 0.54)
EL (1-X)
5.0
2900
(15.0)
1.3
(9.5)
4.0
(9.5)
1.2
(7.0)
564
(0.45, 0.53)
EL (2-A)
4.0
4900
(14.0)
1.7
(9.5)
5.1
(9.5)
1.8
(8.0)
555
(0.44, 0.52)
EL (2-B)
4.5
3200
(15.5)
1.5
(9.5)
4.3
(11.0)
1.4
(9.5)
555
(0.44, 0.52)
EL (2-X)
5.5
1500
(15.0)
0.51
(9.0)
1.4
(8.5)
0.58
(7.0)
568
(0.48, 0.50)
EL (3-A)
6.0
2700
(17.0)
1.1
(11.5)
3.7
(11.5)
1.1
(10.0)
545
(0.46, 0.53)
EL (3-B)
5.0
3700
(15.5)
1.2
(10.0)
4.1
(11.0)
1.2
(10.0)
543
(0.46, 0.53)
EL (3-X)
8.5
1000
(18.0)
0.37
(12.5)
1.3
(12.5)
0.31
(12.5)
545
(0.46, 0.53)
EL (4-A)
4.0
8300
(15.5)
2.9
(10.5)
9.4
(9.5)
3.1
(9.5)
549
(0.42, 0.54)
EL (4-B)
4.0
11000
(15.0)
2.9
(10.0)
9.0
(10.0)
2.8
(10.0)
551
(0.41, 0.54)
EL (4-X)
3.5
4400
(15.5)
1.1
(11.0)
3.1
(11.0)
0.98
(9.0)
569
(0.45, 0.52)
From the above results, the organic EL elements produced by using complexes 1-A, 2-A, 3-A, 4-A, 1-B, 2-B, 3-B, and 4-B exhibit improved organic EL properties in comparison with the organic EL elements produced by using the complexes 1-X, 2-X, 3-X, and 4-X.
INDUSTRIAL APPLICABILITY
The organoiridium complex of the present invention is suitable as a emitting material of the organic EL element because of high photoluminescence quantum yield in the polymer thin film. Particularly, the present invention is suitable as a yellow to green emitting material. | The present invention provides an organometallic complex having a high quantum efficiency even in a polymer thin film as a emitting material for organic electroluminescent (EL) element. The present invention relates to an organoiridium complex for an organic electroluminescent element represented by the following Formula; wherein a C—N ligand including two atomic groups (A 1 , A 2 ), and a β-diketone ligand in line symmetry having two tert-butyl-substituted phenyl groups are coordinated with an iridium atom. The organoiridium complex of the present invention has a high quantum efficiency even in a polymer thin film with respect to green to yellow electroluminescence.
(In the aforementioned Formula, R 1 , R 2 , and R 3 are each a tert-butyl group or a hydrogen atom, and have at least one tert-butyl group; they may bond each other to thereby form a saturated hydrocarbon ring, when having two tert-butyl groups; A 1 , A 2 are each an unsaturated hydrocarbon ring, at least one is a single ring, and at least one is a heterocyclic ring). | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a motion-picture screen for projection of an optical image.
Recently, in accordance with the improvement of the video image technique, the picture (film) for family tends to be shown with a large-sized screen. This tendency requires that the audio system is arranged to provide a sound having an excellent tone quality and a powerful reproduction suitable for the large-sized screen. FIG. 1 is an illustration of an example of AV systems which, in addition to a projector 5 and a screen 10, comprises a central loud speaker 3 principally corresponding to a speech channel, left and right loud speaker 2 and 4 corresponding to background-music-channels, and several surround loud speakers placed at the rear side or the left and right sides of the screen 10. Here, as illustrated in FIG. 2, the screen 10 is constructed with a vinyl chloride sheet 1'a, a white coating 1'b applied on a surface of the vinyl chloride sheet 1'a and a reflection material such as glass beads 1'c, and the screen 10 itself does not have an acoustic permeability.
As disclosed in "About Theater THX system and Home THX system", JAS Journal November 1989, written by Tomlinson Holman, for the picture sound reproduction in a theater, the front-channel loud speaker is disposed at the rear side of the acoustic-permeability type screen so that the image is substantially coincident in position with the picture. On the other hand, since the conventional home-use screen does not have the acoustic permeability as described above, there is a problem which arises with the FIG. 1 AV system, however, in that difficulty is encountered to dispose the central-channel loud speaker 3 at the rear side of the screen 10 as well as in the theater. Accordingly, the central-channel loud speaker 3 is required to be placed at a position which does not cause blocking the projection light from the projector 5 disposed at the front side of the screen 10. This limitation of the placing position can result in the lack of powerful reproduction because the screen position and the sound position are different from each other.
Even if as illustrated in FIG. 3 sound holes 1"a are formed in a screen 1" at a predetermined rate in a screen 1", the air permeability to be obtained is generally about 40 (Frazier type measuring apparatus for air permeability, cm 3 /cm 2 •sec) only. As obvious from FIG. 4, the sound-pressure transmission characteristic in the case that the air permeability is 40 is clearly lower than the sound-pressure transmission characteristic in the case that it is 100. In the case that the air permeability is 100, the sound pressure attenuation is approximately 1 to 2 dB in the band of above 1 kHz and this scarcely provide a problem in practice. On the other hand, in the case that the air permeability is 40, the sound pressure is attenuated such that large peak dips successively occur from the vicinity of 1 kHz. The average sound pressure attenuation is approximately 6 dB and the maximum sound pressure attenuation is above 10 dB. This fact is disclosed in "Sound Transmission Through Perforated Screens" SMPTE Journal, December 1982, written by Michael Rettinger. In this case, difficulty is encountered to perform the characteristic correction by means of electrical circuits or the like.
One possible solution for improving the acoustic transmission characteristic is that the size of the sound-transmission holes is increased and the number of the sound-transmission holes is increased. In this case, there is no problem in the case of being used in the theater, that is, in the case that the screen is placed at a position away from the audience, while in the case of the home-use screen, that is, in the case that the screen is placed at a position relatively close to the audience, the sound-transmission holes can offer a visual problem because of being clearly visible as black spots. One known approach for eliminating such a problem involves using a screen constructed with a weaved knit screen having a predetermined air permeability as disclosed in Japanese Patent Provisional Publication No. 61-98336. Although eliminating the problem due to the sound-transmission holes, this provides a new problem that light penetrates the screen. That is, as illustrated in FIG. 5, a projection light 9 penetrates a screen 1 before being reflected on a wall 7 or the like presented at the rear side of the screen 1. The reflection light 9a illuminates the back of the screen 1 and returns to the projector side. This cause deterioration of the contrast of the image. In FIG. 5, numeral 8 represents a sound wave from the loud speaker 2. In addition, the aforementioned publication also discloses a technique in which a screen is made by performing the aluminium vacuum deposition with respect to a surface of a cloth. However, according to an test, there is a problem which arises with such a technique, however, in that the screen gain is considerably lowered to darken the image. Moreover, the image quality is extremely deteriorated because of the irregularity which appears on the surface of the screen due to the texture of the cloth.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a screen having a high acoustic permeability and a high visual performance.
According to a present invention there is provided a motion-picture screen comprising a weaved knit which has a predetermined air permeability and whose color is substantially white. A dark-colored thin film is formed on one surface of the weaved knit and the other surface of the weaved knit is used as a surface onto which an optical image is projected by a projector. The weaved knit itself can offer an adequate air permeability to ensure an excellent acoustic permeability, and the dark-colored thin film formed on the one surface of the weaved knit can shut light from a wall or the like existing at the rear side of the screen to obtain an excellent contrast. Further, since the surface of the weaved knit itself whose color is substantially white is used as the projection surface of the screen, it is possible to provide a high image quality with less deterioration of the screen gain.
Also, according to this invention there is provided a screen where a metallic thin film is formed on one surface of a weaved knit and the other surface of is weaved knit is used as a surface onto which an optical image is projected by a projector. The formation of the metallic thin film is made by means of the sputtering technique to thereby heighten the adhesion between the formed thin film and the weaved knit to keep a high reliability for a long time.
In this invention, the predetermined air permeability is set to be substantially above 100 cm 3 /cm 2 •sec (when measured by Frazier type measuring apparatus for air permeability).
Further, in accordance with the present invention, there is provided a screen for projecting an optical image, comprising a first weaved knit which has a first predetermined air permeability and whose color is substantially white and a second weaved knit which has a second predetermined air permeability and whose color is substantially black, one surface of the first weaved knits and one surface of the second weaved knit being overlapped one upon another so that the other surface of the first weaved knit is used as a surface onto which said image is projected. Still further, there is provided a screen for projecting an optical image, comprising first and second weaved knits which have first and second predetermined air permeabilities and whose colors are substantially white, a metallic coat which has a dark color being formed on one surface of the second weaved knit, and the first and second weaved knits being overlapped one upon another so that the metallic-coat-formed surface of the second weaved knit is disposed to be in opposed relation to one surface of the first weaved knit and the other surface of the first or second weaved knit is used as a surface onto which the image is projected.
BRIEF DESCRIPTION OF THE DRAWINGS
The object and features of the present invention will become more readily apparent from the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings in which:
FIG. 1 schematically shows an arrangement of an AV system using a conventional sound non-transmitting screen;
FIG. 2 is a partially cross-sectional view showing a structure of a conventional screen;
FIG. 3 is a perspective view showing a conventional screen having sound holes;
FIG. 4 is an illustration of the general relation between the air permeability and the acoustic permeability, i.e., the sound-pressure transmission characteristic;
FIG. 5 partially illustrates an AV system using a general knit as the screen;
FIG. 6 is an illustration of arrangements of screens according to first and second embodiments of the present invention;
FIG. 7 is a schematic illustration of an AV system equipped with a screen according to the present invention;
FIG. 8 is an illustration for describing the functions of the first and second embodiments of this invention;
FIG. 9 is a graphic illustration for describing the sound transmission characteristic to be obtained by this invention;
FIGS. 10 and 11 are illustrations of fibers constituting threads of a screen;
FIG. 12 is a perspective and cross-sectional view showing an arrangement of a screen according to a third embodiment of the present invention;
FIG. 13 is a schematic illustration for describing the function of the third embodiment of this invention; and
FIG. 14 is a perspective and cross-sectional view showing an arrangement of a screen according to a fourth embodiment of this invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 6, there is illustrated a screen according to a first embodiment of the present invention. In FIG. 6, the screen designated at numeral 1 comprises a weaved knit formed by knitting threads whose color is substantially white, the the surface 1a is a projection surface. The surface 1b (opposite surface of 1a) is constructed by forming a colored (deep color) thin film, the surface 1b being arranged so as not to spoil the air permeability of the screen 1. Here, let it be assumed that the screen 1 thus arranged is used in an AV system as illustrated in FIG. 7 where numeral 2 represents a left-side loud speaker, 3 depicts a central loud speaker, 4 designates a right-side loud speaker and 5 denotes a projector. The loud speakers 2 to 4 are placed at the rear side of the screen 1. In FIG. 8, the sound wave 8 generated from the loud speaker 2, 3 or 4 placed at the rear side of the screen 1 can easily pass through the screen without a great deterioration so as to reach the audience 6. At this time, the audience 6 can be exposed to a powerful sound as well as in the theater sound reproduction system because the image position is substantially coincident with the sound position. On the other hand, the light 9 projected from the projector 5 to the screen 1 is reflected on the surface 1a constructed with the substantial white-color threads. A portion of the projected light 9 passes through the screen 1 to reach a wall 7 or the like which exists at the rear side of the screen 1 so as to be reflected thereon. The reflected light directs to the colored thin film (coated surface) 1b side of the screen 1. Here, the reflected light from the wall 7 is absorbed and reflected by the colored thin film 1b so as to prevent it from reaching the audience 6, whereby it is possible to improve the contrast as compared with the conventional screen. In addition, since the surface 1a to be projected with the light 9 is kept substantially white color, the screen gain is scarcely lowered so as to provide an excellent image quality. In cases where the air permeability of the screen 1 is arranged to be substantially above 100, as obvious from FIG. 9, particularly the acoustic permeability is increased.
Here, a description will be made with reference to the following table 1 in terms of the knit cloth with substantial white color which constitutes the screen 1.
TABLE 1______________________________________ Weight of Number AirSample Thread of fibers Number Permea- ScreenNo. (g/1000 m) of Thread of Gages bility Gain______________________________________1 150 48 18 85 0.82 150 48 18 155 0.73 150 48 28 40 14 150 48 28 140 1.4______________________________________
In the table 1, the screen gain is the relative values under the condition that the screen gain of the sample 3 is 1, and the samples 1 to 4 are different in knitted state from each other. The air permeability which is in the correlation to the acoustic permeability cannot be determined only by the size of the thread used and the number of gages but changed in accordance with the knitted states. Thus, for selection of the cloth of the screen, it is first required to select a cloth having a high air permeability.
The number of gages is a value indicating the number of stitches per 1-inch width, and when the number of gages is small, the number of stitches becomes small so that the area of the screen for reflecting the projection light is reduced to lower the screen gain. This is obvious from the fact that in the table 1 the screen gain (1.0) of the sample 3 whose gage number is 28 is higher than the screen gains (0.8, 0.7) of the samples 1 and 2 whose gage number is 18. Further, in the case that the number of gages is small, the concave portions on the surface of the cloth are easily visible as holes, whereby the reproducibility of the outline of the image can be deteriorated. Also in view of the fact that the surface onto which the image is projected is preferable to be flat, the samples 3 and 4 are more preferable in image quality as compared with the samples 1 and 2. Accordingly, the cloth with a larger number of gages is more preferable for constructing the screen.
Further, a description will be made hereinbelow in terms of the fiber constituting the thread. In the table 1, the color of the cloth indicated as the sample 3 is substantially milky and the gloss hardly appear on the surface of the cloth. The fibers constituting each of the threads of the cloth are twisted as illustrated in FIG. 10 so that small irregularities are formed on the surface of the cloth. Accordingly, the light incident on the cloth is diffused by the small irregularities so as to reduce the reflection light toward the audience. On the other hand, the surface of the cloth indicated as the sample 4 has the gloss and is substantially white. The fibers constituting each of the threads of the cloth have substantial bar-like configurations (not twisted) as shown in FIG. 11 so that the small irregularities are are more reduced as compared with the sample 3. Thus, the diffusion of the incident light is suppressed whereby the reflection light to the audience is more increased as compared with the sample 3. This fact is also obvious by the comparison between the screen gains of both the samples 3 and 4 in the table 1, that is, the screen gain of the sample 4 is higher than that of the same 3. Accordingly, it is preferable that the fiber making up the threads of the cloth has a bar-like configuration.
Further, a second embodiment of the present invention will be described hereinbelow. One difference between the first embodiment and the second embodiment is that a metallic thin film is used instead of the above-described dark-colored thin film constituting the screen 1. The second embodiment can also provide an effect to improve the image contrast and the acoustic permeability as well as the first embodiment. The description of the second embodiment will be made with reference to the following table 2 in view of the fact that the screen contrast and screen gain varies in accordance with the thickness of the thin film to be formed on the back of the cloth. Here, the formation of the the metallic thin film is made by means of the stainless sputtering technique.
TABLE 2______________________________________Set Thicknessof Thin Film(angstrom) Contrast Screen Gain______________________________________200 0.7 1.3300 1 1.2400 1.1 1.0______________________________________
In the table 2, the set thickness of the thin fimm shows a set value of a thin-film forming apparatus (a sputtering apparatus), the contrast represents the relative values when the contrast corresponding to the thin-film set thickness is 300, and the screen gain designates the relative values under the condition that the screen gain of the sample 3 in the table 1 is 1.
Unlike the case that the sputtering is effected with respect to a smooth surface such as a resin surface, the thickness of the metallic thin film formed on a surface of a knit in accordance with the sputtering technique is not constant. If the set value of the thickness of the thin film is low, the thin film is partially formed only on the convex portions of the knit surface with a large irregularity and most of the knit surface remains as it is without being coated with the thin film. If this knit is used as the screen 1 in FIG. 8, a portion of the light 9a reflected on the wall 7 after passed through the screen 1 is cut by the thin film 1b so as not to be directed to the audience, while most of the reflection light 9a is directed thereto because of passing through the surface on which the thin film is not formed. As a result, the contrast of the image to be formed on the screen 1 is deteriorated. This is also obvious from the table 2 where the contrast ratio becomes more increased as the set thickness of the thin film becomes more thickened. On the other hand, if the set value of the thickness of the thin film is high, the thin film is formed not only in the gaps between the threads but also in the gaps between the fibers of the threads so that the color (dark color) of the thin film itself is developed on the image-projected surface of the screen 1, thereby lowering the screen gain. Accordingly, the thickness of the thin film is required to be adequately determined in consideration of the screen gain, contrast ratio and others. The table 2 shows the thin film thickness, screen gain and contrast in the case that the sample 4 in the table 1 is used as the screen and these values vary in accordance with the cloth used as the screen.
According to the second embodiment, if the number of gages is set to be large and the fiber constituting the thread is arranged to have a substantial bar-like configuration, it is possible to provide a screen having a high acoustic permeability and allowing a high image quality as well as the above-described first embodiment. In addition, since the metallic thin film is formed in accordance with the sputtering deposition technique, the adhesion between the knit and the thin film is high, and if a rust-proof metal such as a stainless is used as the material of the thin film, the reliability of the screen can be kept for a long time irrespective of cleaning.
Further, a third embodiment of this invention will be described hereinbelow with reference to FIG. 12. In FIG. 12, designated at numeral 1 is a screen according to the third embodiment constructed with a cloth which comprises a weaved knit 1a formed by knitting threads whose color is substantially white and a weaved knit 1b whose color is substantially black. The description will be made with reference to FIG. 13 in terms of the case that the screen 1 thus constructed is used in the AV system as illustrated in FIG. 7. In FIG. 13, the sound wave 8 from the loud speaker 2 (3, 4) placed at the rear side of the screen 1 passes through the screen 1 to reach the audience without the deterioration of the characteristic, whereby the image position is coincident with the sound position and hence a powerful image and sound effect can be obtained as well as the theater sound reproduction system. On the other hand, most of the projection light 9 projected onto the screen 1 is adequately reflected on the white screen surface 1a, but portions 9a and 9b of the projection light 9 penetrate the screen 1 to reach a wall 7 or the like which exists at the rear side of the screen 1. Although the penetration light 9a and 9b are reflected on the wall so as to again reach the screen surface 1b, the reflection light are shut by the weaved knit 1b so as not to be directed to the audience. Further, since the back surface of the white weaved knit 1a is not directly illuminated with the reflection light due to the black weaved knit 1b, the contrast can be improved as compared with the case that the screen 1 is constructed only with the white weaved knit 1a. Still further, since the white weaved knit is kept as it is, the screen gain is scarcely lowered and an excellent image quality can be obtained. As well as the above-described first and second embodiments, in the case that the air permeability of the cloth is set to be above 100, the acoustic permeability can be obtained as shown in FIG. 9 to provide the sound pressure frequency characteristic substantially similar to that of the case of only the loud speaker. Moreover, if the number of gages is arranged to be large and the fiber constituting the thread is arranged to substantially have a bar-like configuration, it is possible to provide a screen having a high acoustic permeability and the screen gain and further allowing a high image quality.
Furthermore, in addition to the effects of the above-described first and second embodiments, the third embodiment can provide the following effects. That is, if the weaved knit is surface-processed with a different material, the surface which is not processed slightly becomes darkened so as to slightly lower the light reflection performance. Since in the case of the third embodiment the surface process is not performed with respect to the projected surface (white weaved knit) 1a, the color of the projection surface of the screen can be kept to be substantially white, thereby keeping the light reflection performance to the value of the weaved knit itself.
A description will be made hereinbelow with reference to FIG. 14 in terms of a fourth embodiment of the present invention. In FIG. 14, designated at numeral 1 is a screen which comprises a weaved knit 1a formed by threads whose color is substantially white and a weaved knit where a dark-color metallic coat or the like is adhered on its surface by means of an adhesion technique. The weaved knits 1a and 1b are overlapped each other so that the metallic-coat adhered surface 1b' of the weaved knit 1b is at the inner side, in other words, both the weaved knits 1a and 1b are piled up on upon another so that the metallic-coat adhered surface 1b' is interposed therebetween as illustrated in FIG. 14. In the case that the cloth thus arranged is used as the screen 1 of the AV system as shown in FIG. 7, this screen 1 can offer the function and effect similar to that of the above-described third embodiment. In addition, this fourth embodiment can provide an advantage that both surfaces of the screen 1 can be used as the image projection surface (1a') under the condition that the weaved knit 1b substantially has white color as well as the weaved knit 1a.
It should be understood that the foregoing relates to only preferred embodiments of the present invention, and that it is intended to cover all changes and modifications of the embodiments of the invention herein used for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention. | A motion-picture screen for projecting an optical image, which comprises a weaved knit having an adequate air permeability. One surface of the weaved knit is coated with a colored material so as to keep a high acoustic permeability concurrently with shutting the light from a wall or the like existing at the rear side of the screen. The other surface of the weaved knit is used as a surface onto which the optical image is projected by a projector, thereby providing an excellent contrast and a high image quality on the screen. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 12/724,021, filed on Mar. 15, 2010, which is a continuation of U.S. patent application Ser. No. 11/589,608, filed on Oct. 30, 2006, now issued as U.S. Pat. No. 7,680,535, which is a continuation of U.S. patent application Ser. No. 10/291,934, filed on Nov. 11, 2002, now issued as U.S. Pat. No. 7,130,688, which is a continuation of U.S. patent application Ser. No. 09/748,798, filed on Dec. 26, 2000, now issued as U.S. Pat. No. 6,480,742, the priority of each of which is claimed, and of each of which is incorporated by reference herein in its respective entirety.
FIELD OF THE INVENTION
[0002] This invention pertains to methods and apparatus for cardiac rhythm management. In particular, the invention relates to methods and apparatus for providing cardiac resynchronization therapy.
BACKGROUND
[0003] Cardiac rhythm management devices are implantable devices that provide electrical stimulation to selected chambers of the heart in order to treat disorders of cardiac rhythm and include pacemakers and implantable cardioverter/defibrillators. A pacemaker is a cardiac rhythm management device that paces the heart with timed pacing pulses. The most common condition for which pacemakers are used is in the treatment of bradycardia, where the ventricular rate is too slow. Atrio-ventricular conduction defects (i.e., AV block) that are permanent or intermittent and sick sinus syndrome represent the most common causes of bradycardia for which permanent pacing may be indicated. If functioning properly, the pacemaker makes up for the heart's inability to pace itself at an appropriate rhythm in order to meet metabolic demand by enforcing a minimum heart rate. Pacing therapy may also be applied in order to treat cardiac rhythms that are too fast, termed anti-tachycardia pacing. (As the term is used herein, a pacemaker is any cardiac rhythm management device with a pacing functionality, regardless of any other functions it may perform such as the delivery cardioversion or defibrillation shocks to terminate atrial or ventricular fibrillation.)
[0004] Also included within the concept of cardiac rhythm is the degree to which the heart chambers contract in a coordinated manner during a cardiac cycle to result in the efficient pumping of blood. The heart has specialized conduction pathways in both the atria and the ventricles that enable the rapid conduction of excitation (i.e., depolarization) throughout the myocardium. These pathways conduct excitatory impulses from the sin θ-atrial node to the atrial myocardium, to the atrio-ventricular node, and thence to the ventricular myocardium to result in a coordinated contraction of both atria and both ventricles. This both synchronizes the contractions of the muscle fibers of each chamber and synchronizes the contraction of each atrium or ventricle with the contralateral atrium or ventricle. Without the synchronization afforded by the normally functioning specialized conduction pathways, the heart's pumping efficiency is greatly diminished. Patients who exhibit pathology of these conduction pathways, such as bundle branch blocks, can thus suffer compromised cardiac output.
[0005] Patients with conventional pacemakers can also have compromised cardiac output because artificial pacing with an electrode fixed into an area of the myocardium does not take advantage of the above-described specialized conduction system. The spread of excitation from a single pacing site must proceed only via the much slower conducting muscle fibers of either the atria or the ventricles, resulting in the part of the myocardium stimulated by the pacing electrode contracting well before parts of the chamber located more distally to the electrode, including the myocardium of the chamber contralateral to the pacing site. Although the pumping efficiency of the heart is somewhat reduced from the optimum, most patients can still maintain more than adequate cardiac output with artificial pacing.
[0006] Heart failure is a clinical syndrome in which an abnormality of cardiac function causes cardiac output to fall below a level adequate to meet the metabolic demand of peripheral tissues and is usually referred to as congestive heart failure (CHF) due to the accompanying venous and pulmonary congestion. CHF can be due to a variety of etiologies with ischemic heart disease being the most common. Some CHF patients suffer from some degree of AV block or are chronotropically deficient such that their cardiac output can be improved with conventional bradycardia pacing. Such pacing, however, may result in some degree of incoordination in atrial and/or ventricular contractions due to the way in which pacing excitation is spread throughout the myocardium as described above. The resulting diminishment in cardiac output may be significant in a CHF patient whose cardiac output is already compromised. Intraventricular and/or interventricular conduction defects (e.g., bundle branch blocks) are also commonly found in CHF patients. In order to treat these problems, cardiac rhythm management devices have been developed which provide electrical pacing stimulation to one or more heart chambers in an attempt to improve the coordination of atrial and/or ventricular contractions, termed cardiac resynchronization therapy.
[0007] In order for cardiac resynchronization therapy to be effective, resynchronization pacing pulses should be delivered as often as possible. If the pacemaker is operating in a mode where pacing is inhibited by intrinsic cardiac activity, this means that a pace must be delivered before such intrinsic activation takes place. Pacemakers have various programmable pacing parameters that affect the extent to which paces are delivered and not inhibited by intrinsic beats. In order to optimally adjust these parameters, an informative record of sensing and pacing events over a period of time is needed. It is toward this general problem that the present invention is directed.
SUMMARY OF THE INVENTION
[0008] The present invention is a system and method for recording sensing and pacing events in a cardiac pacemaker that provides useful information for adjusting pacing parameters in order to optimally deliver cardiac resynchronization therapy. In accordance with the invention, paces delivered to a heart chamber occurring as a result of the expiration of different escape intervals or trigger events are separately counted. Each event that may cause a pace is assigned an isolated counter to count the number of paces that occur by reason of that event. For example, in the case of ventricular pacing, separate counters may be provided for expiration of the lower rate limit ventricular escape interval, the atrio-ventricular interval expiration in atrial-tracking ventricular pacing modes, and a ventricular sense in the case of a ventricular-triggered mode. The count of the paces due to each event may be expressed as a percentage of total cardiac cycles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a system diagram of a pacemaker configured for biventricular pacing and sensing.
[0010] FIGS. 2 through 5 illustrates examples of data produced by separate and non-separate pace counters.
DESCRIPTION OF THE INVENTION
[0011] In order to properly deliver ventricular resynchronization therapy, it is important to pace the ventricles to as great an extent as possible. If the pacemaker is operating in a synchronous mode where paces are inhibited by intrinsic activity, this can be brought about by optimal adjustment of pacing parameters such as the length of escape intervals. A clinician may properly set the parameters initially, but changes in the patient's condition over time may render those parameter values inappropriate for optimally delivering resynchronization therapy. Pacemakers typically collect diagnostic data over time which can be downloaded by an external programmer using a data link. This data includes counts of senses received from sensing channels and counts of paces delivered. In order to optimally configure the pacemaker for delivering resynchronization therapy, however, more information than that is needed. Specifically, information is needed that enables a clinician to determine the reasons why paces are or are not being delivered. The present invention provides this by separately counting pacing events using isolated pace counters.
[0012] 1. Hardware Platform
[0013] Pacemakers are typically implanted subcutaneously and have leads threaded intravenously into the heart to connect the device to electrodes used for sensing and pacing. A programmable electronic controller causes the pacing pulses to be output in response to lapsed time intervals and sensed electrical activity (i.e., intrinsic heart beats not as a result of a pacing pulse). Pacemakers sense intrinsic cardiac electrical activity by means of internal electrodes disposed near the chamber to be sensed. A depolarization wave associated with an intrinsic contraction of the atria or ventricles that is detected by the pacemaker is referred to as an atrial sense or ventricular sense, respectively. In order to cause such a contraction in the absence of an intrinsic beat, a pacing pulse (either an atrial pace or a ventricular pace) with energy above a certain pacing threshold is delivered to the chamber.
[0014] FIG. 1 shows a system diagram of a microprocessor-based pacemaker physically configured with sensing and pacing channels for both atria and both ventricles. The controller 10 of the pacemaker is a microprocessor which communicates with a memory 12 via a bidirectional data bus. The memory 12 typically comprises a ROM (read-only memory) for program storage and a RAM (random-access memory) for data storage. The pacemaker has atrial sensing and pacing channels comprising electrode 34 A-B, leads 33 A-B, sensing amplifiers 31 A-B, pulse generators 32 A-B, and atrial channel interfaces 30 A-B which communicate bidirectionally with microprocessor 10 . The device also has ventricular sensing and pacing channels for both ventricles comprising electrodes 24 A-B, leads 23 A-B, sensing amplifiers 21 A-B, pulse generators 22 A-B, and ventricular channel interfaces 20 A-B. In the figure, “A” designates one ventricular or atrial channel and “B” designates the channel for the contralateral chamber. In this embodiment, a single electrode is used for sensing and pacing in each channel, known as a unipolar lead. Other embodiments may employ bipolar leads which include two electrodes for outputting a pacing pulse and/or sensing intrinsic activity. The channel interfaces 20 A-B and 30 A-B include analog-to-digital converters for digitizing sensing signal inputs from the sensing amplifiers and registers which can be written to by the microprocessor in order to output pacing pulses, change the pacing pulse amplitude, and adjust the gain and threshold values for the sensing amplifiers. An exertion level sensor 330 (e.g., an accelerometer or a minute ventilation sensor) enables the controller to adapt the pacing rate in accordance with changes in the patient's physical activity. A telemetry interface 40 is also provided for communicating with an external programmer 500 which has an associated display 510 . A pacemaker incorporating the present invention may possess all of the components in FIG. 1 and be programmable so as to operate in a number of different modes, or it may have only those components necessary to operate in a particular mode.
[0015] The controller 10 controls the overall operation of the device in accordance with programmed instructions stored in memory. The controller 10 controls the delivery of paces via the pacing channels, interprets sense signals from the sensing channels, implements timers for defining escape intervals and sensory refractory periods, and performs the pace counting functions as described below. It should be appreciated, however, that these functions could also be performed by custom logic circuitry either in addition to or instead of a programmed microprocessor.
[0016] 2. Bradycardia Pacing Modes
[0017] Bradycardia pacing modes refer to pacing algorithms used to pace the atria and/or ventricles when the intrinsic atrial and/or ventricular rate is inadequate due to, for example, AV conduction blocks or sinus node dysfunction. Such modes may either be single-chamber pacing, where either an atrium or a ventricle is paced, or dual-chamber pacing in which both an atrium and a ventricle are paced. The modes are generally designated by a letter code of three positions where each letter in the code refers to a specific function of the pacemaker. The first letter refers to which heart chambers are paced and which may be an A (for atrium), a V (for ventricle), D (for both chambers), or O (for none). The second letter refers to which chambers are sensed by the pacemaker's sensing channels and uses the same letter designations as used for pacing. The third letter refers to the pacemaker's response to a sensed P wave from the atrium or an R wave from the ventricle and may be an I (for inhibited), T (for triggered), D (for dual in which both triggering and inhibition are used), and O (for no response). Modern pacemakers are typically programmable so that they can operate in any mode which the physical configuration of the device will allow. Additional sensing of physiological data allows some pacemakers to change the rate at which they pace the heart in accordance with some parameter correlated to metabolic demand. Such pacemakers are called rate-adaptive pacemakers and are designated by a fourth letter added to the three-letter code, R.
[0018] Pacemakers can enforce a minimum heart rate either asynchronously or synchronously. In asynchronous pacing, the heart is paced at a fixed rate irrespective of intrinsic cardiac activity. There is thus a risk with asynchronous pacing that a pacing pulse will be delivered coincident with an intrinsic beat and during the heart's vulnerable period which may cause fibrillation. Most pacemakers for treating bradycardia today are therefore programmed to operate synchronously in a so-called demand mode where sensed cardiac events occurring within a defined interval either trigger or inhibit a pacing pulse Inhibited demand pacing modes utilize escape intervals to control pacing in accordance with sensed intrinsic activity. In an inhibited demand mode, a pacing pulse is delivered to a heart chamber during a cardiac cycle only after expiration of a defined escape interval during which no intrinsic beat by the chamber is detected. If an intrinsic beat occurs during this interval, the heart is thus allowed to “escape” from pacing by the pacemaker. Such an escape interval can be defined for each paced chamber. For example, a ventricular escape interval can be defined between ventricular events so as to be restarted with each ventricular sense or pace. The inverse of this escape interval is the minimum rate at which the pacemaker will allow the ventricles to beat, sometimes referred to as the lower rate limit (LRL).
[0019] In atrial tracking pacemakers (i.e., VDD or DDD mode), another ventricular escape interval is defined between atrial and ventricular events, referred to as the atrio-ventricular interval (AVI). The atrio-ventricular interval is triggered by an atrial sense or pace and stopped by a ventricular sense or pace. A ventricular pace is delivered upon expiration of the atrio-ventricular interval if no ventricular sense occurs before. Atrial-tracking ventricular pacing attempts to maintain the atrio-ventricular synchrony occurring with physiological beats whereby atrial contractions augment diastolic filling of the ventricles. If a patient has a physiologically normal atrial rhythm, atrial-tracking pacing also allows the ventricular pacing rate to be responsive to the metabolic needs of the body.
[0020] A pacemaker can also be configured to pace the atria on an inhibited demand basis. An atrial escape interval is then defined as the maximum time interval in which an atrial sense must be detected after a ventricular sense or pace before an atrial pace will be delivered. When atrial inhibited demand pacing is combined with atrial-triggered ventricular demand pacing (i.e., DDD mode), the lower rate limit interval is then the sum of the atrial escape interval and the atrio-ventricular interval.
[0021] Another type of synchronous pacing is atrial-triggered or ventricular-triggered pacing. In this mode, an atrium or ventricle is paced immediately after an intrinsic beat is detected in the respective chamber. Triggered pacing of a heart chamber is normally combined with inhibited demand pacing so that a pace is also delivered upon expiration of an escape interval in which no intrinsic beat occurs. Such triggered pacing may be employed as a safer alternative to asynchronous pacing when, due to far-field sensing of electromagnetic interference from external sources or skeletal muscle, false inhibition of pacing pulses is a problem. If a sense in the chamber's sensing channel is an actual depolarization and not a far-field sense, the triggered pace is delivered during the chamber's physiological refractory period and is of no consequence.
[0022] Finally, rate-adaptive algorithms may be used in conjunction with bradycardia pacing modes. Rate-adaptive pacemakers modulate the ventricular and/or atrial escape intervals based upon measurements corresponding to physical activity. Such pacemakers are applicable to situations in which atrial tracking modes cannot be used. In a rate-adaptive pacemaker, for example, the LRL is adjusted in accordance with exertion level measurements such as from an accelerometer or minute ventilation sensor in order for the heart rate to more nearly match metabolic demand. The adjusted LRL is then termed the sensor-indicated rate.
[0023] 3. Cardiac Resynchronization Therapy
[0024] Cardiac resynchronization therapy is pacing stimulation applied to one or more heart chambers in a manner that restores or maintains synchronized bilateral contractions of the atria and/or ventricles and thereby improves pumping efficiency. Certain patients with conduction abnormalities may experience improved cardiac synchronization with conventional single-chamber or dual-chamber pacing as described above. For example, a patient with left bundle branch block may have a more coordinated contraction of the ventricles with a pace than as a result of an intrinsic contraction. In that sense, conventional bradycardia pacing of an atrium and/or a ventricle may be considered as resynchronization therapy. Resynchronization pacing, however, may also involve pacing both ventricles and/or both atria in accordance with a synchronized pacing mode as described below. A single chamber may also be resynchronized to compensate for intra-atrial or intra-ventricular conduction delays by delivering paces to multiple sites of the chamber.
[0025] It is advantageous to deliver resynchronization therapy in conjunction with one or more synchronous bradycardia pacing modes, such as are described above. One atrial and/or one ventricular pacing sites are designated as rate sites, and paces are delivered to the rate sites based upon pacing and sensed intrinsic activity at the site in accordance with the bradycardia pacing mode. In a single-chamber bradycardia pacing mode, for example, one of the paired atria or one of the ventricles is designated as the rate chamber. In a dual-chamber bradycardia pacing mode, either the right or left atrium is selected as the atrial rate chamber and either the right or left ventricle is selected as the ventricular rate chamber. The heart rate and the escape intervals for the pacing mode are defined by intervals between sensed and paced events in the rate chambers only. Resynchronization therapy may then be implemented by adding synchronized pacing to the bradycardia pacing mode where paces are delivered to one or more synchronized pacing sites in a defined time relation to one or more selected sensing and pacing events that either reset escape intervals or trigger paces in the bradycardia pacing mode. Multiple synchronized sites may be paced through multiple synchronized sensing/pacing channels, and the multiple synchronized sites may be in the same or different chambers as the rate site.
[0026] In bilateral synchronized pacing, which may be either biatrial or biventricular synchronized pacing, the heart chamber contralateral to the rate chamber is designated as a synchronized chamber. For example, the right ventricle may be designated as the rate ventricle and the left ventricle designated as the synchronized ventricle, and the paired atria may be similarly designated. Each synchronized chamber is then paced in a timed relation to a pace or sense occurring in the contralateral rate chamber.
[0027] One synchronized pacing mode may be termed offset synchronized pacing. In this mode, the synchronized chamber is paced with a positive, negative, or zero timing offset as measured from a pace delivered to its paired rate chamber, referred to as the synchronized chamber offset interval. The offset interval may be zero in order to pace both chambers simultaneously, positive in order to pace the synchronized chamber after the rate chamber, or negative to pace the synchronized chamber before the rate chamber. One example of such pacing is biventricular offset synchronized pacing where both ventricles are paced with a specified offset interval. The rate ventricle is paced in accordance with a synchronous bradycardia mode which may include atrial tracking, and the ventricular escape interval is reset with either a pace or a sense in the rate ventricle. (Resetting in this context refers to restarting the interval in the case of an LRL ventricular escape interval and to stopping the interval in the case of an AVI.) Thus, a pair of ventricular paces are delivered after expiration of the AVI escape interval or expiration of the LRL escape interval, with ventricular pacing inhibited by a sense in the rate ventricle that restarts the LRL escape interval and stops the AVI escape interval. In this mode, the pumping efficiency of the heart will be increased in some patients by simultaneous pacing of the ventricles with an offset of zero. However, it may be desirable in certain patients to pace one ventricle before the other in order to compensate for different conduction velocities in the two ventricles, and this may be accomplished by specifying a particular positive or negative ventricular offset interval.
[0028] Another synchronized mode is triggered synchronized pacing. In one type of triggered synchronized pacing, the synchronized chamber is paced after a specified trigger interval following a sense in the rate chamber, while in another type the rate chamber is paced after a specified trigger interval following a sense in the synchronized chamber. The two types may also be employed simultaneously. For example, with a trigger interval of zero, pacing of one chamber is triggered to occur in the shortest time possible after a sense in the other chamber in order to produce a coordinated contraction. (The shortest possible time for the triggered pace is limited by a sense-to-pace latency period dictated by the hardware.) This mode of pacing may be desirable when the intra-chamber conduction time is long enough that the pacemaker is able to reliably insert a pace before depolarization from one chamber reaches the other. Triggered synchronized pacing can also be combined with offset synchronized pacing such that both chambers are paced with the specified offset interval if no intrinsic activity is sensed in the rate chamber and a pace to the rate chamber is not otherwise delivered as a result of a triggering event. A specific example of this mode is ventricular triggered synchronized pacing where the rate and synchronized chambers are the right and left ventricles, respectively, and a sense in the right ventricle triggers a pace to the left ventricle and/or a sense in the left ventricle triggers a pace to the right ventricle.
[0029] As with other synchronized pacing modes, the rate chamber in a triggered synchronized pacing mode can be paced with one or more synchronous bradycardia pacing modes. If the rate chamber is controlled by a triggered bradycardia mode, a sense in the rate chamber sensing channel, in addition to triggering a pace to the synchronized chamber, also triggers an immediate rate chamber pace and resets any rate chamber escape interval. The advantage of this modal combination is that the sensed event in the rate chamber sensing channel might actually be a far-field sense from the synchronized chamber, in which case the rate chamber pace should not be inhibited. In a specific example, the right and left ventricles are the rate and synchronized chambers, respectively, and a sense in the right ventricle triggers a pace to the left ventricle. If right ventricular triggered pacing is also employed as a bradycardia mode, both ventricles are paced after a right ventricular sense has been received to allow for the possibility that the right ventricular sense was actually a far-field sense of left ventricular depolarization in the right ventricular channel. If the right ventricular sense were actually from the right ventricle, the right ventricular pace would occur during the right ventricle's physiological refractory period and cause no harm.
[0030] As mentioned above, certain patients may experience some cardiac resynchronization from the pacing of only one ventricle and/or one atrium with a conventional bradycardia pacing mode. It may be desirable, however, to pace a single atrium or ventricle in accordance with a pacing mode based upon senses from the contralateral chamber. This mode, termed synchronized chamber-only pacing, involves pacing only the synchronized chamber based upon senses from the rate chamber. One way to implement synchronized chamber-only pacing is to pseudo-pace the rate chamber whenever the synchronized chamber is paced before the rate chamber is paced, such that the pseudo-pace inhibits a rate chamber pace and resets any rate chamber escape intervals. Such pseudo-pacing can be combined with the offset synchronized pacing mode using a negative offset to pace the synchronized chamber before the rate chamber and thus pseudo-pace the rate chamber, which inhibits the real scheduled rate chamber pace and resets the rate chamber pacing escape intervals. One advantage of this combination is that sensed events in the rate chamber will inhibit the synchronized chamber-only pacing, which may benefit some patients by preventing pacing that competes with intrinsic activation (i.e., fusion beats). Another advantage of this combination is that rate chamber pacing can provide backup pacing when in a synchronized chamber-only pacing mode, such that when the synchronized chamber pace is prevented, for example to avoid pacing during the chamber vulnerable period following a prior contraction, the rate chamber will not be pseudo-paced and thus will be paced upon expiration of the rate chamber escape interval. Synchronized chamber-only pacing can be combined also with a triggered synchronized pacing mode, in particular with the type in which the synchronized chamber is triggered by a sense in the rate chamber. One advantage of this combination is that sensed events in the rate chamber will trigger the synchronized chamber-only pacing, which may benefit some patients by synchronizing the paced chamber contractions with premature contralateral intrinsic contractions.
[0031] An example of synchronized chamber-only pacing is left ventricle-only synchronized pacing where the rate and synchronized chambers are the right and left ventricles, respectively. Left ventricle-only synchronized pacing may be advantageous where the conduction velocities within the ventricles are such that pacing only the left ventricle results in a more coordinated contraction by the ventricles than with conventional right ventricular pacing or biventricular pacing. Left ventricle-only synchronized pacing may be implemented in inhibited demand modes with or without atrial tracking, similar to biventricular pacing. A left ventricular pace is then delivered upon expiration of the AVI escape interval or expiration of the LRL escape interval, with left ventricular pacing inhibited by a right ventricular sense that restarts the LRL escape interval and stops the AVI escape interval.
[0032] In the synchronized modes described above, the rate chamber is synchronously paced with a mode based upon detected intrinsic activity in the rate chamber, thus protecting the rate chamber against paces being delivered during the vulnerable period. In order to provide similar protection to a synchronized chamber or synchronized pacing site, a synchronized chamber protection period (SCPP) may be provided. (In the case of multi-site synchronized pacing, a similar synchronized site protection period may be provided for each synchronized site.) The SCPP is a programmed interval which is initiated by sense or pace occurring in the synchronized chamber during which paces to the synchronized chamber are inhibited. For example, if the right ventricle is the rate chamber and the left ventricle is the synchronized chamber, a left ventricular protection period LVPP is triggered by a left ventricular sense which inhibits a left ventricular pace which would otherwise occur before the escape interval expires. The SCPP may be adjusted dynamically as a function of heart rate and may be different depending upon whether it was initiated by a sense or a pace. The SCPP provides a means to inhibit pacing of the synchronized chamber when a pace might be delivered during the vulnerable period or when it might compromise pumping efficiency by pacing the chamber too close to an intrinsic beat. In the case of a triggered mode where a synchronized chamber sense triggers a pace to the synchronized chamber, the pacing mode may be programmed to ignore the SCPP during the triggered pace. Alternatively, the mode may be programmed such that the SCPP starts only after a specified delay from the triggering event, which allows triggered pacing but prevents pacing during the vulnerable period.
[0033] In the case of synchronized chamber-only synchronized pacing, a synchronized chamber pace may be inhibited if a synchronized chamber sense occurs within a protection period prior to expiration of the rate chamber escape interval. Since the synchronized chamber pace is inhibited by the protection period, the rate chamber is not pseudo-paced and, if no intrinsic activity is sensed in the rate chamber, it will be paced upon expiration of the rate chamber escape intervals. The rate chamber pace in this situation may thus be termed a safety pace. For example, in left ventricle-only synchronized pacing, a right ventricular safety pace is delivered if the left ventricular pace is inhibited by the left ventricular protection period and no right ventricular sense has occurred.
[0034] As noted above, synchronized pacing may be applied to multiple sites in the same or different chambers. The synchronized pacing modes described above may be implemented in a multi-site configuration by designating one sensing/pacing channel as the rate channel for sensing/pacing a rate site, and designating the other sensing/pacing channels in either the same or the contralateral chamber as synchronized channels for sensing/pacing one or more synchronized sites. Pacing and sensing in the rate channel then follows rate chamber timing rules, while pacing and sensing in the synchronized channels follows synchronized chamber timing rules as described above. The same or different synchronized pacing modes may be used in each synchronized channel.
[0035] 4. Ventricular Rate Regularization
[0036] Ventricular rate regularization (VRR) is a ventricular pacing mode in which the LRL of the pacemaker is dynamically adjusted in accordance with a detected intrinsic ventricular rate. When a pacemaker is operating in a ventricular pacing mode (e.g., VVI or DDD), intrinsic ventricular beats occur when the instantaneous intrinsic rate rises above the LRL of the pacemaker. Thus, paces are interspersed with intrinsic beats, and the overall ventricular rhythm as a result of both paces and intrinsic beats is determined by the LRL and the mean value and variability of the intrinsic ventricular rate. VRR regularizes the overall ventricular rhythm by adjusting the LRL of the pacemaker in accordance with changes in the measured intrinsic rate.
[0037] 5. Pace Counter Isolation
[0038] Resynchronization therapy is only as effective as to the extent to which paces are delivered and not inhibited by intrinsic activity. In order to provide a clinician with diagnostic information enabling proper adjustment of pacing parameters to optimally deliver cardiac resynchronization therapy, data needs to be collected by the pacemaker which reflects the events responsible for causing paces to be delivered or inhibited over a period of time. In accordance with the present invention, isolated pace counters are provided for separately counting different pacing events in each pacing channel. Depending upon the pacing mode which is being used, separate counters are provided for separately counting paces due to expiration of different escape intervals and triggering events. In a ventricular resynchronization pacing mode, for example, counters are provided for separately counting paces delivered to rate ventricular rate chamber due to expiration of a ventricular escape interval corresponding to the lower rate limit setting and due to expiration of the atrio-ventricular interval in an atrial tracking mode. Separate counters are also provided to count paces delivered to the rate and/or synchronized ventricles that are triggered by ventricular senses in a ventricular triggered mode. Separate counts of senses from each sensing channel may be also maintained.
[0039] FIGS. 2 through 5 illustrate examples of how the separate pace counters can be used for diagnostic purposes in order to optimally deliver ventricular resynchronization therapy. Each figure shows the sense and pace counts as they would be collected by non-separated counters, and the same data as reflected by isolated counters in accordance with the invention. The counts are shown for sensing and pacing events in each ventricular sensing/pacing channel. In all cases, the counts are presented as a percentage of total cardiac cycles.
[0040] FIG. 2 shows exemplary counts collected by a pacemaker operating in an atrial tracking mode with one ventricular sensing/pacing channel. It is desirable in such a situation that ventricular paces should track the atria as much as possible. The non-separated counter column shows that the ventricle is being 100% paced. However, the isolated counters reveal that the reason for the ventricular pacing is all due to expiration of the LRL escape interval. This indicates that the LRL setting is inappropriately programmed in order for the pacing rate to be controlled by intrinsic atrial activity.
[0041] FIG. 3 shows another example of data collected by a pacemaker with one sensing/pacing channel operating in an atrial tracking mode. The non-separated counters indicate that the ventricles are being 100% paced, which is what is desired in ventricular resynchronization pacing. However, the separated pace counters reveal that many of the ventricular paces are not occurring at the expiration of the atrio-ventricular interval indicating too high an atrial rate, the effect of VRR, or other condition interfering with proper AV sequential pacing.
[0042] FIG. 4 shows data collected by a pacemaker with right and left ventricular sensing channels operating in a left ventricular-only pacing mode that includes ventricular rate regularization and biventricular triggering. FIG. 5 shows the same data as in FIG. 4 , but presented to show the total pace counts due to all events for each ventricular channel and separate counts for each type of pacing event expressed as a percentage of the total paces in that channel. In this example, what is desired is left ventricular pacing due to expiration of the LRL ventricular escape interval. The non-separated counters show that the left ventricle is paced frequently, but not at the ideal of 100%. Also, the percentage of right ventricular paces is quite high, and it is clear that this is due to frequent left ventricular senses occurring (i.e., right ventricular safety paces are being delivered). The separated counters help to diagnose the situation. The right ventricular counters reveal that there has been a right ventricular safety pace on 25% of the cycles which indicated oversensing of the left ventricle. The right ventricular counters also show that 60% of the cycles were triggered right ventricular paces, while the left ventricular counters show that only 45% of the cycles had a triggered left ventricular pace. This further indicates a left ventricular oversensing situation. Finally, it can be seen that only 15% of the cycles were of the type desired, a left ventricular pace due to expiration of the LRL escape interval.
[0043] The above-described embodiments dealt with ventricular resynchronization pacing modes in which the right and left ventricles were designated as the rate and synchronized chambers, respectively. Embodiments may similarly be constructed in which contralateral heart chambers are designated as the rate and synchronized chambers or in which a plurality of synchronized channels are utilized to provide synchronized pacing to multiple sites of a single chamber. In each of these cases, separate counters may be maintained for each sensing/pacing channel.
[0044] Although the invention has been described in conjunction with the foregoing specific embodiment, many alternatives, variations, and modifications will be apparent to those of ordinary skill in the art. Such alternatives, variations, and modifications are intended to fall within the scope of the following appended claims. | A system and method for recording sensing and pacing events in a cardiac rhythm management device. The method may be particularly useful in assessment of pacing parameters for ventricular resynchronization therapy. | 0 |
[0001] This application incorporates by reference Taiwanese application Serial No. 90100657, filed Jan. 11, 2001.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to a driving method for a plasma display panel (hereinafter referred to as PDP) and a circuit thereof, particularly to a driving method for reducing a voltage difference of the sustaining electrode and circuit thereof.
[0004] 2. Description of the Related Art
[0005] Please refer to FIG. 1, it shows a cross-sectional view of a conventional PDP structure. There are several sustaining electrodes X and scanning electrodes Y alternately disposed on the surface of the front glass substrate 102 and are parallel to each other. Each of the sustaining electrode X or scanning electrode Y comprises a transparent electrode 106 and an auxiliary electrode 108 . The auxiliary electrode 108 is used to increase the conductivity of the transparent electrode 106 . A dielectric layer 110 is positioned on the transparent electrode 106 and the auxiliary electrode 108 , and a protective layer 112 covers the dielectric layer 110 .
[0006] A plurality of address electrodes 114 , which are perpendicular to the sustaining electrodes X and the scanning electrodes Y, are positioned on the surface of the rear glass substrate 104 . Each address electrode 114 is formed below a fluorescent layer 116 and ribs (not shown in FIG. 1). The discharge space 118 is formed between the protective layer 112 and the fluorescent layer 116 . The discharge space is filled with discharge gas, for instance, inert gases.
[0007] Referring to FIG. 2, it is the diagram of the electrode arrangement of the conventional PDP. The sustaining electrode X and the scanning electrode Y are alternately disposed, that is, these electrodes are arranged by the order of scanning electrode Y( 1 ), sustaining electrode X( 1 ), scanning electrode Y( 2 ) and sustaining electrode X( 2 ). The address electrodes A( 1 ), A( 2 ), A( 3 ) and A( 4 ) are perpendicular to the sustaining electrodes X and the scanning electrodes Y. Each discharge cell E 1 , can be turned on and off, is defined by the sustaining electrode X, scanning electrode Y and address electrode A.
[0008] Referring to FIG. 3, it is the diagram showing another electrode arrangement of the conventional PDP. The sustaining electrode X and the scanning electrode Y are arranged by the order of YXXY, that is, the electrodes are arranged by the order of the scanning electrode Y( 1 ), sustaining electrode X( 1 ), sustaining electrode X( 2 ) and the scanning electrode Y( 2 ). The address electrode A( 1 ), A( 2 ), A( 3 ) and A( 4 ) are perpendicular to the sustaining electrodes X and the scanning electrodes Y. Each discharge element E 2 , can be selectively turned on and off, is defined by each sustaining electrode X, scanning electrode Y and address electrode A.
[0009] Referring to FIG. 4, it is the diagram of the driving waveform for driving the conventional PDP in FIG. 2 or FIG. 3. In this driving method, there are three periods in each subfield, including a reset period P 1 , an address period P 2 , and a sustain period P 3 . The following description is the operation of a PDP having n sustaining electrodes X( 1 )˜X(n), n scanning electrodes Y( 1 )˜Y(n) and m address electrodes A( 1 )˜A(m).
[0010] To make sure that the data can be addressed correctly in the pixels, in the reset period P 1 , a priming pulse 402 of 340V is applied to the sustaining electrodes X( 1 )˜X(n), and an erase pulse 404 with a positive voltage, a reset pulse 406 with a negative voltage and a stabilizing priming pulse 408 are sequentially applied to the scanning electrodes Y( 1 )˜Y(n). The wall charges of the discharge cells are reset to a certain energy state by the pulses described above. Those pulses also reduce the ionized charges in the discharge space 118 .
[0011] During the address period P 2 , lots of scanning pulses 410 of−180V are inputted to the scanning electrodes Y( 1 ) 1 ˜Y(n). A voltage V 1 , about 60V, is applied to the sustaining electrodes X( 1 )˜X(n). According to the image data to be displayed, the address pulse 412 of 60V is selectively inputted to the address electrodes A( 1 )˜A(m) for producing wall charges. Therefore, the wall charges can be increased in the selected discharge cells, and are used as the initial charges for a subsequent sustain period P 3 .
[0012] During the sustain period P 3 , the discharge cells emit UV light and the user will see visible light as UV photons hit the fluorescent layer 116 . By the memory effect of the wall charges, the discharge cells are lighted after applying an alternating current with opposite polarities to the scanning electrodes Y( 1 )˜Y(n) and the sustain electrodes X( 1 )˜X(n). The signals applied to the scanning electrodes Y( 1 )˜Y(n) and the sustain electrodes X( 1 )˜X(n), are in a range between 180V and 0V, and these signals include a plurality of discharge sustaining pulse 414 .
[0013] Please refer to FIG. 5 which is a block diagram of the circuit and used to drive the conventional PDP in FIG. 2 or FIG. 3. Take n=8 as an example. The Y driving circuit 502 includes a reset/scan circuit 504 and a Y sustaining circuit 506 . The reset/scan circuit 504 should provide at lease one signal with a positive voltage and one signal with a negative voltage, so the reset/scan circuit 504 is a positive/negative polarity circuit. During the reset period P 1 or the address period P 2 , the reset/scan circuit 504 provides signals with voltages of 180V, −90V or −180V to the scanning electrodes Y. During the sustain period P 3 , the sustaining circuit 506 provides signals with voltages of 180V or 0V to the scanning electrodes Y. During the address period P 2 and the sustain period P 3 , the Y driving circuit 502 provides the signals to the multiplexer 508 and the scanning IC 510 which is electrically connected to all of the scanning electrodes Y( 1 )˜Y( 8 ). The scanning IC 510 sequentially outputs the scanning pulse 410 to the scanning electrodes Y( 1 )˜Y( 8 ) during the address period P 2 , and simultaneously provides discharge sustaining pulses 414 to the scanning electrode Y( 1 )˜Y( 8 ) during the sustain period P 3 . Moreover, all of the sustaining electrodes X are coupled to the X driving circuit 514 . The X driving circuit 514 includes a reset circuit 516 and a X sustaining circuit 512 . The reset circuit 516 only provides signals with a positive voltage, so the reset circuit 516 is a positive polarity circuit.
[0014] Referring to FIG. 6, it shows the current IX of the sustaining electrode X, and the voltage of the sustaining electrode X and the scanning electrode Y during the sustain period P 3 in FIG. 4. After the discharge sustaining pulse 414 is applied, the discharge cell is discharged, and a current Ids will pass through the sustaining electrode X, scanning electrode Y, X sustaining circuit 512 and Y sustaining circuit 506 . The X sustaining circuit 512 and the Y sustaining circuit 506 include a lot of transistors, every transistor has its resistance, and the total resistance of these transistors is defined as Rds. When the current Ids is formed, a voltage difference V=Ids*Rds is occurred within a very short time because of the resistances Rds of these transistors. When the electric current flows out of one electrode, the voltage difference V is negative, and a notch may appear in the voltage waveform of the electrode. When the electric current flows in the electrode, the voltage difference V is positive, and a peak may appear in the voltage waveform of the electrode. In addition, whether a notch or a peak is formed may depend on the signals applied on these electrodes. When the sustaining electrode X is in a positive voltage (e.g. 180V) and the scanning electrode is in a relative negative voltage (e.g. 0V), the instant voltage difference V cause a voltage notch 602 a in the voltage waveforms of the sustaining electrode X and a peak 602 b in the voltage waveforms of the scanning electrode Y. The voltage difference V can be as higher as 60V. Therefore, the actual voltage waveforms of the sustaining electrode X and the scanning electrode Y are different from these of the inputted signals of the driving circuits. The voltage operation margin of the PDP is then reduced, and the electromagnetic radiation interference (EMI) becomes seriously when the notch or the peak is formed.
[0015] U.S. Pat. No. 6,072,449 discloses a method for driving the PDP and a method can reduce the instant voltage difference V. The voltage and the current waveforms for the sustaining electrode X and the scanning electrode Y are shown in FIG. 7. First, the scanning electrodes Y are divided to two groups including first scanning electrodes Y 1 and second scanning electrodes Y 2 . Take a first scanning electrode Y 1 and a second scanning electrode Y 2 as the example, the discharge sustaining pulses with different phases are applied, respectively. Therefore, on the sustaining electrode X, the displacement current 702 caused by the voltage difference of the first scanning electrode Y 1 , the displacement current 702 ′ caused by the voltage difference of the sustaining electrode X, the discharge current 704 of the sustaining electrode X and the first scanning electrode Y 1 , the displacement current 706 caused by the voltage difference of the second scanning electrode Y 2 , and the discharge current 708 of the sustaining electrode X and the second scanning electrode Y 2 will appear at different times. Therefore, the discharge currents 704 , 708 become smaller. According to the above-mentioned equation V=Ids*Rds, the instant voltage difference can be reduced when the current is reduced. The voltage notches 710 , 712 or peaks 714 , 716 formed by the instant voltage difference V can also be reduced. However, the circuit is very complex, and thereby the cost is very high.
[0016] Referring to FIG. 8, it shows the block diagram of the driving circuit to produce the waveform in FIG. 7. The first scanning electrode Y 1 and the second scanning circuit Y 2 are respectively coupled to the scanning IC 810 and the scanning IC 820 . There are many transistors in the Y driving circuit 802 , so the scanning ICs 810 , 820 can't couple to only one Y driving circuit 802 . Every scanning IC must couple to a corresponding Y driving circuit to output a different driving waveform. Therefore, the scanning ICs 810 and 820 are respectively coupled to the Y driving circuits 802 and 812 through the multiplexer 808 and 818 . The Y driving circuit 802 includes a reset/scan circuit 804 and a Y sustaining circuit 806 , and the Y driving circuit 812 includes a reset/scan circuit 814 and a Y sustaining circuit 816 . The reset/scan circuits 804 , 814 are negative/positive polarity reset circuits. A X driving circuit 826 includes a reset circuit 828 and a X sustaining circuit 824 . Moreover, the Y driving circuits 802 and 812 respectively receive control signals C_Y( 1 ) and the C_Y( 2 ) from the phase shift controller 822 to produce different discharge sustaining pulses. The phase shift controller 822 further transmits one control signal C_X( 1 ) to the X sustaining circuit 824 to maintain the synchronization of the sustaining circuit 806 , 816 and 824 . However, there are so many components in the above-mentioned circuit, the prior circuit would be very complicated and the manufacturing cost is high.
SUMMARY OF THE INVENTION
[0017] From the above description, the object of the present invention is to provide a driving method of a Plasma Display Panel (PDP)and circuit thereof. The driving method and circuit of the PDP reduces the voltage difference effectively and increases the operation margin. Especially, the driving method reduces the electromagnetic interference of the PDP efficiently. The object of the present invention is achieved with only a simple circuit.
[0018] According to the object of the present invention, a driving method of the PDP is disclosed. The PDP includes a first sustaining electrode, a second sustaining electrode, a scanning electrode and a data electrode. The scanning electrode is parallel to the first sustain electrode and the second sustain electrode. The data electrode is perpendicular to the first sustaining electrode. The driving method includes steps of: (a) providing an address period, (b) applying a scanning pulse to the scanning electrode during the address period and selectively applying a data pulse to the data electrode for writing in an image data, (c) providing a sustain period, and (d) applying a first pulse and a second pulse with different phases to the first sustaining electrode and the second sustaining electrode, and applying a third pulse to the scanning electrode for maintaining the image data. The first pulse and the second pulse produce a first discharge current and a second discharge current on the first sustaining electrode and the second sustaining electrode, and an time interval is formed between the second discharge current and the first discharge current to reduce an instant power consumption of the PDP.
[0019] According to another object of the present invention, a PDP driving circuit is also disclosed. The PDP includes a scanning electrode, a first sustaining electrode, a second sustaining electrode and a data electrode. The scanning electrode is parallel to the first sustain electrode and the second sustain electrode. The data electrode is perpendicular to the first sustaining electrode. The driving circuit of the PDP includes a Y driving circuit, a scanning IC, a first X sustaining circuit, a second X sustaining circuit and a phase shift controller. The scanning IC is coupled to the scanning electrode and the Y driving circuit. The first X sustaining circuit is coupled to the first sustaining electrode X 1 , and the second X sustaining circuit is coupled to the second sustaining electrode X 2 . The phase shift controller is coupled to the first X sustaining circuit and the second X sustaining circuit, the phase shift controller is commanded the first X sustaining circuit and the second X sustaining circuit to output a first and a second pulse, and the first and second pulse are in different phases.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above objects and other advantages of the present invention will become more apparently by describing in detail the preferred embodiment of the present invention with reference to the attached drawings in which:
[0021] [0021]FIG. 1 is the cross section showing the conventional structure of a Plasma Display Panel (PDP);
[0022] [0022]FIG. 2 is the diagram of the electrode arrangement for the YXYX-type according to the conventional PDP;
[0023] [0023]FIG. 3 is the diagram of the electrode arrangement for the YXXY-type according to the conventional PDP;
[0024] [0024]FIG. 4 is the diagram of the driving waveform used to drive the conventional PDP in FIG. 2 or FIG. 3;
[0025] [0025]FIG. 5 is the block diagram of the circuit used to drive the conventional PDP in FIG. 2 or FIG. 3;
[0026] [0026]FIG. 6 shows the waveforms of the current IX for the sustaining electrode X and the voltage for the sustaining electrode X and the scanning electrode Y during the sustain period P 3 in FIG. 4;
[0027] [0027]FIG. 7 shows the voltage and the current waveforms for the sustaining electrode X and the scanning electrode Y according to the method for driving the PDP in U.S. Pat. No. 6,072,449;
[0028] [0028]FIG. 8 shows the block diagram of a circuit for forming the waveform in FIG. 7;
[0029] [0029]FIG. 9 shows the current waveforms of the first sustaining electrode X 1 , the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 according to the preferred embodiment in the present invention;
[0030] [0030]FIG. 10 shows the block diagram of a driving circuit used for a PDP having the YXYX-type electrode arrangement according to the preferred embodiment in the present invention;
[0031] [0031]FIG. 11 shows block diagram of a driving circuit used for a PDP having the YXXY-type electrode arrangement according to the preferred the embodiment in the present invention;
[0032] [0032]FIG. 12A shows a part of the X sustaining circuit according to the conventional method in FIG. 8;
[0033] [0033]FIG. 12B shows a part of the first X sustaining circuit according to the driving circuit of FIG. 10 in the present invention;
[0034] [0034]FIG. 13 shows the enlargement of a part of the waveform in FIG. 9;
[0035] [0035]FIG. 14 shows the sustain discharge waveform according to the second embodiment in the present invention; and
[0036] [0036]FIG. 15 shows block diagram of a driving circuit using two different scanning ICs.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] In the present invention, the sustaining electrodes X are divided into two groups, including the first sustaining electrodes X 1 and the second sustaining electrodes X 2 . The scanning electrodes Y are also divided into two groups including the first scanning electrodes Y 1 and the second electrodes Y 2 . Take a first sustaining electrode, a second sustaining electrode, a first scanning electrode, and a second scanning electrode as the example in the follow description.
[0038] During the sustain period P 3 , the first and second discharge sustaining pulses with different phases are applied to the first sustaining electrode X 1 and the second sustaining electrode X 2 , respectively. The third discharge sustaining pulse is applied to the first scanning electrode Y 1 and the second scanning electrode Y 2 . Thus, the first discharge current and the second discharge current are outputted from the first sustaining electrode X 1 and the second sustaining electrode X 2 . The second discharge current appears after the first discharge current for a delay time. The instant power consumption of the PDP is reduced and the voltage differences (notches or peaks) of the first sustaining electrode X 1 , the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 are also reduced.
[0039] Referring to FIG. 9, it shows the voltage and current waveforms of the first sustaining electrode X 1 , the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 in the preferred embodiment. Several sustaining signals IN _Y 1 , IN_Y 2 , IN_X 1 and IN_X 2 are inputted from the outer circuits (not shown) to the first scanning electrode Y 1 , the second scanning electrode Y 2 , the first sustaining electrode X 1 , the second sustaining electrode X 2 , respectively. Then, the voltage waveforms of the first scanning electrode Y 1 , the second scanning electrode Y 2 , the first sustaining electrode X 1 , the second sustaining electrode X 2 are shown as VY 1 , VY 2 , VX 1 , VX 2 . The current waveforms of the first scanning electrode Y 1 , the second scanning electrode Y 2 , the first sustaining electrode X 1 , the second sustaining electrode X 2 are shown as IY 1 , IY 2 , IX 1 , IX 2 , respectively.
[0040] In FIG. 9, the first discharge sustaining pulse 902 applied to the first sustaining electrode X 1 and the second discharge sustaining pulse 904 applied to the second sustaining electrode X 2 have different phases. Therefore, the first rising edge 906 of the first discharge sustaining pulse 902 and the second rising edge 908 of the second discharge sustaining pulse 904 are staggered. The first rising edge 906 appears before the falling edge 912 of the third discharge sustaining pulse 910 . The second rising edge 908 appears after the falling edge 912 of the third discharge sustaining pulse 910 . The third discharge sustaining pulse 910 is the signal inputted to the first scanning electrode Y 1 and the second scanning electrode Y 2 .
[0041] As voltage differences of the first sustaining electrode X 1 and the first scanning electrode Y 1 happen, first displacement currents 922 and 924 are generated. A first discharge current 926 will appear when the voltage difference between the first sustaining electrode X 1 and the first scanning electrode Y 1 is larger than a threshold voltage. Moreover, as voltage differences of the second sustaining electrode X 2 and the second scanning electrode Y 2 happen, second displacement currents 932 and 934 appear. A second discharge current 936 will be generated if the voltage difference between the second sustaining electrode X 2 and the second scanning electrode Y 2 is larger than the threshold voltage.
[0042] The first discharging current 926 and the second discharging current 936 are staggered because the phases of the first sustain discharging pulse 902 and the second sustain discharging pulse 904 are different. A delay time D 1 is formed between the second discharging current 936 and the first discharging current 926 . Therefore, the instant power consumption of the PDP can be reduced. The voltage differences (notches or peaks) 940 , 942 , 946 , 948 of the first sustaining electrode X 1 , the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 can be reduce, and so as the electromagnetic interference (EMI) do.
[0043] In FIG. 10, it shows the block diagram of the driving circuit used in the PDP having a YXYX-type electrode arrangement according to the preferred embodiment in the present invention. The sustaining electrodes X are divided into two groups, including a first sustaining electrodes X 1 and a second sustaining electrodes X 2 . Those electrodes are alternately disposed. For example, the first sustaining electrodes X 1 include the first sustaining electrode X 1 ( 1 ), X 1 ( 2 ), X 1 ( 3 ), X 1 ( 4 ), and the second sustaining electrodes X 2 include the second sustaining electrode X 2 ( 1 ), X 2 ( 2 ), X 2 ( 3 ) and X 2 ( 4 ). All first sustaining electrodes X 1 are coupled to the first sustaining circuit 1002 , and all second sustaining electrodes X 2 are coupled to the second X sustaining circuit 1004 . These X sustaining circuits 1002 and 1004 are used to provide the driving waveforms. Furthermore, a phase shift controller 1006 is coupled to the first X sustaining circuit 1002 and the second X sustaining circuit 1004 to provide the first discharge sustaining pulse 902 to the first X sustaining circuit 1002 and provide the second discharge sustaining pulse 904 to the second X sustaining circuit 1004 . The first and second discharge sustaining pulses 902 , 904 are in different phases. Only one reset circuit 1005 is coupled to the first X sustaining circuit 1002 and the second X sustaining circuit 1004 . The reset circuit 1005 is a positive polarity reset circuit.
[0044] The first scanning electrode Y 1 and the second scanning electrode Y 2 are both coupled to the scanning IC 1008 , and the scanning IC 1008 is further connected with the multiplexer 1010 of the Y driving circuit 1012 . The Y driving circuit 1012 includes a reset/scan circuit 1014 and a Y sustaining circuit 1016 . The reset/scan circuit 1014 is a negative/positive polarity reset circuit. During the reset period P 1 and the address period P 2 , the reset/scan circuit 1014 provides a voltage, for instance 180V, −90V or −180V, to the first scanning electrode Y 1 and the second scanning electrode Y 2 . During the sustain period P 3 , the Y sustaining circuit 1016 provides a voltage of 180V or 0V to the first scanning electrode Y 1 and the second scanning electrode Y 2 .
[0045] By a control signal (not shown in FIG. 10), the Y sustain scanning driving circuit 1012 provides different driving signals to the first scanning electrode Y 1 and the second scanning electrode Y 2 during the address period P 2 and the sustain period P 3 . These driving signals are transmitted to the scanning IC 1008 via the multiplexer 1010 .
[0046] During the address period P 2 , scanning pulses are outputted to the first scanning electrodes Y 1 ( 1 )˜Y( 4 ) and the second scanning electrodes Y 2 ( 1 )˜Y 2 ( 4 ) in order by the scanning IC 1008 . During the sustain period P 3 , several sustain discharging pulses 910 are applied to the first scanning electrode Y 1 ( 1 )˜Y 1 ( 4 ) and the second scanning electrode Y 2 ( 1 )˜Y 2 ( 4 ) by the scanning IC 1008 simultaneously.
[0047] Please refer to FIG. 11, it shows the block diagram of another driving circuit used in the PDP having a YXXY-type electrode arrangement in the present invention. The sustaining electrodes X are divided into two groups, including a first sustaining electrodes X 1 and the second sustaining electrodes X 2 . The scanning electrodes Y are divided into two groups, including first scanning electrodes Y 1 and second scanning electrodes Y 2 . For example, the first sustaining electrodes X 1 include the first sustaining electrode X 1 ( 1 ), X 1 ( 2 ), X 1 ( 3 ), X 1 ( 4 ), the second sustaining electrodes X 2 include the second sustaining electrode X 2 (l), X 2 ( 2 ), X 2 ( 3 ) and X 2 ( 4 ), the first scanning electrodes Y 1 include the first scanning electrode Y 1 ( 1 ), Y 1 ( 2 ), Y 1 ( 3 ), Y 1 ( 4 ), and the second scanning electrodes Y 2 include the second scanning electrode Y 2 ( 1 ), Y 2 ( 2 ), Y 2 ( 3 ) and Y 2 ( 4 ). These electrodes are arranged by the order of Y( 1 ), X 1 ( 1 ), X 1 ( 2 ), Y 1 ( 2 ), Y 2 (l), X 2 ( 1 ), X 2 ( 2 ), Y 2 ( 2 ), Y 3 (l), . . . etc. Meanwhile, all first sustaining electrodes X 1 are coupled to a first X sustaining circuit 1102 , and all second sustaining electrodes X 2 are coupled to a second X sustaining circuit 1104 . The phase shift controller 1106 is coupled to the first X sustaining circuit 1102 and the second X sustaining circuit 1104 . Only one reset circuit 1105 is coupled to the first X sustaining circuit 1002 and the second X sustaining circuit 1004 .
[0048] Please refer to FIGS. 12A and 12B. FIG. 12A shows a part of the conventional X sustaining circuit 824 in FIG. 8, and FIG. 12B shows a part of the first X sustaining circuit 1002 of FIG. 10 in the present invention. In FIG. 12A, the conventional X sustaining circuit 824 must use at least 4 transistors Q 1 , Q 2 , Q 3 , and Q 4 , which are controlled by control signals S 1 , S 2 , S 3 , and S 4 to provide the currents to all the sustaining electrodes X. In the present invention, the sustaining electrodes X are divided into two groups, only two transistors Q 1 ′ and Q 2 ′, controlled by the control signals S 1 ′, S 2 ′, are used to drive the first sustaining electrode X 1 because the number of the first sustaining electrode X 1 is reduced. The total transistors of the first X sustaining circuit 1002 and the second X sustaining circuit 1004 are the same as that in the conventional X sustaining circuit 824 although two sustaining circuits are used in the present invention. Therefore, the number of the transistors for driving the sustaining electrode X will not be increased.
[0049] Please refer to FIG. 13, it shows the enlargement of the waveforms in FIG. 9. The scanning signals IN_Y 1 and IN_Y 2 , the sustaining signals IN_X 1 and IN_X 2 , the current signals IX 1 , IX 2 , IY 1 , IY 2 are further explained below.
[0050] The sustain period P 3 is further divided into several periods. During a period T 1 , a sustaining voltage is provided to the first sustaining electrode X 1 , for example, the voltage of the first sustaining electrode X 1 is raised from 0 V to a high voltage of 180V. At the same time, the second sustaining electrode X 2 , the first scanning electrode Y 1 , and the second scanning electrode Y 2 are maintained at constant voltages. The second sustaining electrode X 2 is maintained at a first voltage, such as a low voltage of 0V. The first scanning electrode Y 1 and the second scanning electrode Y 2 are maintained at a scanning voltage, such as a high voltage of 180V.
[0051] During a period T 2 , the voltages of the first scanning electrode Y 1 and the second scanning electrode Y 2 are reduced from the scanning voltage to a second voltage. The second voltage is a low voltage, for example, the voltages of these electrodes are reduced from 180V to 0V. The first sustaining electrode X 1 and the second electrode X 2 are maintained at the sustaining voltage and the first voltage, respectively. After this period T 2 , the plasma between the first scanning electrode Y 1 and the first sustaining electrode X 1 is triggered and a first discharge current 926 is produced because the voltage difference between the first scanning electrode Y 1 and the first sustaining electrode X 1 is larger than a threshold voltage.
[0052] During a period T 3 , a sustaining voltage is provided to the second sustaining electrode X 2 . The voltage of the second sustaining electrode X 2 is increased from 0V to 180V. At the same time, the first scanning electrode Y 1 and the second scanning electrode Y 2 are remained at the second voltage (0V). The first sustaining electrode X 1 still maintains at the sustaining voltage (180V). After the period T 3 , the plasma between the second scanning electrode Y 2 and the second sustaining electrode X 2 is triggered and the second discharge current 936 is produced. The second discharge current 936 is produced after the first discharge current 926 is produced for a delay time D 1 . The first and second discharge currents are not occurred at the same time, so the instant power consumption of the PDP may be reduced.
[0053] Generally, the first discharge current 926 appears after a delay of 0.5˜1ì s from the end of the period T 2 and the second discharge current 936 appears after a delay of 0.5˜1ì s from the end of the period T 3 in FIG. 13.
[0054] Then, during a period T 4 , the voltage of the first sustaining electrode X 1 is reduced from the sustaining voltage to a third voltage. The third voltage is a low voltage, such as 0V. At the same time, the first scanning electrode Y 1 and the second scanning electrode Y 2 are maintained at the second voltage (0V), and the second sustaining electrode X 2 is maintained at the sustaining voltage (180V) during the period T 4 . Similarly, during a period T 5 , the voltages of the first scanning electrode Y 1 and the second scanning electrode Y 2 are increased to the scanning voltage, such as 180V. The first sustaining electrode X 1 and the second sustaining electrode X 2 are maintained at the third voltage and the sustaining voltage during the period T 5 , respectively. During a period T 6 , the voltage of the second sustaining electrode X 2 is reduced to a fourth voltage. The fourth voltage is a low voltage, the voltage of the second sustaining electrode X 2 is reduced from the high voltage of 180V to the low voltage of 0V. The first sustaining electrode X 1 is maintained at the third voltage (0V), the first scanning electrode Y 1 and the second scanning electrode Y 2 are remained at the scanning voltage (180V) during the period T 6 . Therefore, a third discharge current 928 having an opposite phase to the first discharge current 926 is produced on the first sustaining electrode X 1 . A fourth discharge current 938 with an opposite phase to the second discharge current 936 is also produced on the second sustaining electrode X 2 . A delay time D 2 is happened during the third discharge current 928 and fourth discharge current 938 .
[0055] Please refer to FIG. 14, it shows another sustain discharge waveform according to the second embodiment in the present invention. During the period T 1 ′, T 2 ′ and T 3 ′, the variation of the voltages of the first sustaining electrode X 1 , the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 are the same as that during the first, second, third periods T 1 , T 2 , and T 3 in FIG. 13. In the periods T 4 ′, T 5 ′, and T 6 ′, the voltage variations of these electrodes are different. During the period T 4 ′, the first sustaining electrode is maintained at the sustaining voltage (180V), but the voltage of the second sustaining electrode X 2 is reduced to a low voltage such as 0V. At the same time, the first scanning electrode Y 1 and the second scanning electrode Y 2 are maintained at the low voltage of 0V.
[0056] Next, during a period T 5 ′, the first scanning electrode Y 1 and the second scanning electrode Y 2 are increased to the scanning voltage (180 V). At the same period, the voltages of the first sustaining electrode X 1 and the second sustaining electrode X 2 are maintained at the sustaining voltage (180V) and the low voltage (0V), respectively. Similarly, during a period T 6 ′, the first sustaining electrode X 1 is decreased to the low voltage such as 0V. The voltages applied to the second sustaining electrode X 2 , the first scanning electrode Y 1 and the second scanning electrode Y 2 maintain at constant values (0V, 180V, 180V) during the period T 6 ′. Therefore, the third discharge current 928 , having an opposite phase to the first discharge current 926 , is produced on the second sustaining electrode X 2 . And the fourth discharge current 938 with the opposite phase to the second discharge current 936 is produced on the first sustaining electrode X 1 .
[0057] All scanning electrodes Y are connected to one scanning IC 1008 or 1108 as shown in FIG. 10 or FIG. 11. However, it will not limit the scope of the present invention. In FIG. 15, it shows block diagram of another driving circuit for the PDP. These scanning electrodes are divided into two groups, including a first scanning electrode Y 1 and a second scanning electrode Y 2 , and coupled to different scanning ICs. The first scanning electrode Y 1 is coupled to the scanning IC 1508 , and the second scanning electrode Y 2 is coupled to the scanning IC 1518 . The sustain Y driving circuit 1512 includes a reset/scan circuit 1514 , a sustaining circuit 1516 , and a multiplexer 1510 . The Y driving circuit 1522 includes a reset/scan circuit 1524 , a sustaining circuit 1526 , and a multiplexer 1520 . The scanning IC 1508 and 1518 are coupled to the multiplexer 1510 , 1520 , respectively. The first sustaining electrode X 1 is coupled to the X sustaining circuit 1502 and the second sustaining electrode X 2 is coupled to the X sustaining circuit 1504 . The phase shift controller 1506 is coupled to the X sustaining circuit 1502 , X sustaining circuit 1504 , the sustain Y driving circuit 1512 and Y driving circuit 1522 . The scanning IC 1508 and the scanning IC 1518 output the third discharge sustaining pulse and the fourth discharge sustaining pulse. The phases of the third sustain discharge and the fourth sustain discharge can be the same or different.
[0058] Based on the scope of the present invention, the sustaining electrode X can be divided into N set, and N>2. As long as the phases of the discharge sustaining pulses applied to the N set electrodes are different, the purpose of the present invention is achieved.
[0059] From the above description, the driving method and circuit of the sustaining electrode in the present invention can reduce the voltage notch effectively, increase the operation margin, and reduce the electromagnetic interference of the PDP. And the purpose in the present invention is achieved with a simple circuit.
[0060] Once given the above disclosure, many other features, modifications, and improvements will become apparent to the skilled artisan. Such other features, modifications, and improvements are, therefore, considered to be a part of this invention, the scope of which is to be determined by the following claims. | A driving method of a plasma display panel and a driving circuit thereof are disclosed. In the method, image data is inputted by applying a scanning pulse to the scanning electrode and selectively applying a data pulse to the data electrode during an address period. Then, a first pulse and a second pulse of different phase are respectively applied to the first sustaining electrode and the second sustaining electrode during a sustain period. A third pulse is applied to the scanning electrode to sustain the image data. A first discharge current and a second discharge current are occurred, an time interval is formed between the discharge currents to reduce an instant power consumption of the PDP. The driving method is also used to reduce the electromagnetic interference and increases the operation margin. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device preferably used for pumping oil or other fluid from a drill hole in the ground, the device including a pump with a driving motor under it and connected to the pump, which are lowered into the drill hole.
The pump comprises a hydraulic screw machine including a screw array including a drive screw and at least one running screw co-acting therewith, arranged in a housing with the drive screw connected to a shaft extending outside the housing on the low pressure side of the device, the screws being provided on the low pressure side of the screw array with mutually co-acting balancing pistons adapted for hydraulically balancing the screws against axially acting forces.
2. Description of the Prior Art
In pumping such as crude oil from deep drill holes in the ground it is known to use centrifugal pumps and piston pumps lowered in the holes. The use of such pumps is associated with certain disadvantages, however. The disadvantages limiting the use of centrifugal pumps are that they have long extension in the longitudinal direction of the drill hole, since they must be provided with several stages connected in series for pumping up from great depths, and also that they have relatively poor efficiency when used for high oil viscosities. A disadvantage limiting the use of piston pumps is that they can only be used at relatively small depths since piston stroke will otherwise be unacceptably long.
Attempts have also been made to utilize screw pumps for conveying oil from drill holes, but these attempts have not been very successful, since it has been found to be very difficult to manufacture an effectively functioning pump with a radial inlet and an axial outlet at the end of the pump opposite the inlet, which is a requirement for its use as a drill hole pump.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a device preferably for pumping oil or other fluid up from a drill hole in the ground, said device including a screw machine which can be used at very large depths and there take up large hydrostatic pressure, and which also can pump liquid with extremely large inlet and outlet pressures, with different viscosities and with relatively large gas content, the machine having a relatively small axial extension and a rotation of direction which may be temporarily reversed for cleaning a strainer or the like covering the inlet of the machine.
This object is achieved by the invention having been given the distinguishing features disclosed in the characterizing portions of the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, partially cut-away side view of a device in accordance with the invention in use in a drill hole in the ground, and
FIG. 2 is a side view, showing planes cutting each other at right angles, of a screw machine included in the device illustrated in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A drill hole made in the ground is denoted by B in FIG. 1. A typical drill hole may be 12,7 cm in diameter and 5,000 m deep. A pipe 1 is driven into the drill hole B, which is partially filled with such as crude oil and gas. Under its prevailing pressure oil is supplied to the interior of the pipe 1 via openings 1a at its lower end. There are means 2 at the upper end of the pipe, inter alia for pumping away oil from the drill hole and for retaining and operating the equipment used to pump oil up from the drill hole. This equipment includes an electric motor 3 with power supply from the means 2 via a cable 6, a hydraulic screw machine 4 rigidly bolted to the motor and acting as a pump, as well as a pipe string 5 bolted to the pump and consisting of a plurality of jointed pipes extending to the means 2.
A central portion of the pump 4 is illustrated in FIG. 2. The end members denoted by 7 and 8 of the pump are bolted to the motor 3 and the pipe string 5, respectively, as illustrated in FIG. 1. The end members 7 and 8 are threaded into the pipe housing 9. The end member 7 is provided with an opening 10 disposed directly opposite a radial inlet opening 11 to the interior of the housing 9, and the opening 10 is covered by a strainer 12 attached to the circular surface of the member 7.
The pump housing 9 is provided with a passage formed by three mutually intersecting cylindrical bores, the central one of which accommodates a drive screw 13, and both the outer bores accommodate running screws meshing with the drive screw, only one running screw 14 being illustrated in FIG. 2.
The passage formed by the bores extends with a constant cross-section through the entire housing 9 from one end to the other, one end being open towards a space 16 between the pump and motor and the other end being open towards a space 15 between the pump and the pipe string 5.
The drive screw 13 is made conventionally with convex threads and the running screws 14 with concave threads, the crests of the threads being sealingly surrounded by the bores with the threads sealing against each other. Between the threads and the housing there are thus formed mutually sealed chambers wherein oil is conveyed through the screw array. In the illustrated case the openings 10, 11 are at the downward end of the housing 9 in FIG. 1, which is the left-hand end in FIG. 2, and the screws rotate such that the oil is conveyed through the openings 10, 11 which communicate with the space between the pipe 1 and pump 4, the oil coming in radially and being conveyed by the screws towards the space 15 and further up through the pipe string 5 for further conveying via the means 2.
The unthreaded end portions of the running screws 14 form balancing pistons 22, which radially engage against the walls of the outer bores and form narrow gaps towards the axial surface of the drive screw end portion. The drive screw 13 is provided with a balancing piston 24 of the same diameter as the crests thereof and engaging radially against the wall of the central bore. The piston 24 is located outside the pistons 22 and its face 23 towards the drive screw thread is situated adjacent the faces 25 of the pistons 22 remote from the running screw threads so that a variable gap A is formed between them.
The drive screw 13 continues outside the balancing piston 24 with a shaft 20 which is journalled in a bearing 21 arranged in a part of the housing 9 formed as a cover 30. The shaft 20 is provided with splines for enabling removable coupling to the output shaft of the electric motor 3.
A balancing collar 26 is attached to the drive screw 13 adjacent the face of the balancing piston 24 remote from the drive screw. The left-hand (in FIG. 2) radial side of the collar 26, together with the cover 30, the axial surface of the drive screw 13 and wear ring 27 (on the cover 30) and 29 (on the collar 26), defines a first pressure chamber 28, and the radial side (to the right in FIG. 2) of the collar 26 defines, together with the axial surface of the balancing piston 24, the faces 25 of the balancing pistons 22 and the wall of the passage in the housing 9, a second pressure chamber 32.
The inlet of the first pressure chamber 28 is in communication with the pump outlet at 15 via an axial bore 36 through the drive screw and a radial bore 38 communicating therewith through the drive screw and opening out into the pressure chamber 28 at the axial surface of the drive screw. The outlet of the first pressure chamber 28 consists of a variable gap C between the wear rings 27 and 29.
The inlet to the second pressure chamber 32 comprises a through, axial hole 34 in the balancing collar 26 and the inlet at the gap C, which thus connects the first and second pressure chambers, while the outlet of the second pressure chamber 32 consists of the gap A.
Oil is introduced to the first pressure chamber 28 via the bores 36 and 38 at a pressure substantially corresponding to the outlet pressure at 15 of the pump, this pressure also acting on the substantially radial end surfaces of the screws 13 and 14, to the right in FIG. 2, and strives to displace the screws to the left in this FIGURE. The left, annular side surface of the collar 26, between the axial surface 13 of the drive screw and the wear ring 29, is greater than the combined radial sectional surfaces of the three bores in the housing 9, and therefore the oil pressure acting on this side surface strives to displace the drive screw to the right.
The gap C, which forms a hydrostatic bearing between the washer 26 and the housing part 30, will vary in width in response to the pressure in the pressure chamber 28 and in response to the axial forces acting on the drive screw. For an increased axial force to the left on the drive screw, the pressure in the pressure chamber 28 will increase, since the gap C becomes less, which results in that the drive screw via the collar 26 strives to return to the right.
There is a pressure in the second pressure chamber 32 substantially comprising the sum of the pressure at the low pressure or inlet side of the pump and the pressure provided by the communication, via the hole 34 and the gap C, with the first pressure chamber 28, which is also in communication with the high pressure or outlet side of the pump. The hole 34 is dimensioned such that the pressure in the pressure chamber 32 will always be so much greater than the axial pressure acting on the running screws 14 that the output flow gap A between the balancing pistons 22 and 24 is maintained and mechanical contact between their surfaces 23 and 25 is avoided. The dimension of the hole 34 may be regulatable for adjusting the pump to different operating conditions.
The screw machine in accordance with the invention has been described above in conjunction with pumping oil up out of a drill hole B, the electric motor 3 driving the screw array 13, 14 in one direction of rotation. However, the rotational direction of the electric motor is reversible for temporarily being able to reverse the rotational direction of the screw array so that oil is pumped in through the outlet (at 15) and out through the inlet (at 10, 11). Foreign matter which may have collected on the outside of the strainer 12, making it more difficult, or even preventing oil from being sucked in through the inlet 10, 11, is thus forced away from the strainer so that it becomes clear again. Due to the balancing described above, the screw array will not be subjected to unpermitted, large axial stresses during its rotation in the opposite direction.
By the implementation of, and co-action between, the different parts and pressure chambers of the machine, it is ensured that the screw machine described above may be used as a drill hole pump, in which the axial forces acting on the drive and running screws are balanced for ensuring an effective and reliable mode of operation under the special conditions existing in a deep drill hole.
Although only one embodiment of the invention has been described above and illustrated on the drawings, it will be understood that the invention is not limited to this embodiment, but only by the disclosures in the claims. | A device preferably utilized for pumping oil or other fluid from a drill hole in the ground, said device including a pump lowered into the hole and coupled to a drive motor situated under it. The pump comprises a hydraulic screw pump including a housing in which there is mounted a screw array in the form of a drive screw provided with a shaft coupled to the drive motor, and at least one running screw meshing with the drive screw. The rotational direction of the drive motor is such that the screw array pumps the liquid from an inlet, made radially in the housing and in communication with the liquid in the drill hole, to an outlet arranged at the end of the screw array remote from said shaft. | 4 |
This application is a continuation of application Ser. No. 08/416,884, filed as PCT/GB93/02191 Oct. 22, 1993, published as WO94/09234 Apr. 28, 1994, now abandoned.
The present invention relates to a locking mechanism, notably to a latch mechanism for a display container.
BACKGROUND TO THE INVENTION
Compact discs, audio and video tapes are usually put up for sale in a plastic case or the like, which carries information about the disc or tape as well as carrying sales promotional material or artwork to attract a purchaser. The case is often displayed at the point of sale in an open access rack or other display so that a would-be purchaser can browse through the display and select the discs or tapes he wishes to purchase. However, in order to reduce the risk of theft from such an open access display, the actual disc or tape is not held within the displayed case, but is stored separately. Therefore, when the disc or tape is purchased, the sales person has to identify the disc or tape from the empty case, to locate the disc or tape in the store and to marry the disc or tape up with the empty case. This is time consuming and may also require that the sales person leaves the sales counter un-manned whilst locating the disc or tape in the store.
In order to reduce these problems, it has been proposed to fit the case into a display container fitted with a lock mechanism which secures the case for the disc or tape within the container so that a thief cannot readily gain access to the disc or tape without breaking the container or removing the container from the shop. The container can be fitted with alarm means so that it cannot be removed from the display or shop without actuating an audible or visual alarm. Typically, the container is locked by means of a spring loaded pin which engages a recess or the like in a wall of the case. The pin is retracted by applying a strong magnet to the pin mounting, for example at the sales counter, so as to release the case from the container. However, such mechanisms are either bulky and obtrusive, or can be accessed externally so that the security of the container is compromised. Furthermore, the pin must register with a recess in the wall of the case and this limits the range of cases which can be used within a given container, notably where the design of the case is altered by the manufacturer. The pin must also be retracted when the case is loaded into the display container, which again is time consuming.
In my PCT Application No GB 92/00633, I have described and claimed a novel form of security container which reduces the above problems and which is adapted to contain one or more articles, which container has access means whereby the article(s) can be inserted into or removed from the container, the container being provided with a detent mechanism adapted to retain the article within the container, which detent mechanism comprises:
a. a sole plate member located adjacent the interior of one wall of the container and adapted to move axially substantially parallel to the plane of that wall and to bear against a face of the article which is to be inserted into or removed from the container through said access means;
b. a biassed member adapted to move between an operative position at which the member engages the sole plate member so as to retain it against axial movement, and an inoperative position at which the biassed member permits axial movement of the sole plate member; and
c. a stop member, preferably carried by said sole plate member, adapted to engage said article and to retain said article within the container when said biassed member engages the sole plate member in its operative position.
Preferably there is a second stop member carried by the sole plate member which is adapted to engage said article as it is inserted into the container, whereby the sole plate member is moved axially by said article as it is inserted into the container so that the first stop member prevents removal of the article from the container when the sole plate is carried by the article to the position at which the sole plate member is engaged by the biassed member.
I have now devised a simplified form of the detent mechanism which can be made in a modular form so as to fit a number of different forms of existing container without the need to modify those containers. The simplified form of detent mechanism can be applied to the container during manufacture thereof, or can be applied as a retro-fit component with little or no modification to existing containers.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides a detent mechanism adapted to be mounted on a container which is to contain one or more articles, which container has an access aperture through which the article(s) can be inserted into or removed from the container, the detent mechanism being adapted to retain the article within the container, which detent mechanism comprises:
a. a mounting member adapted to be carried externally of the container and, preferably, adjacent the access aperture of the container;
b. a latch member adapted to be carried externally of the container by the mounting member and adapted to move between a retracted position at which at least the distal end thereof is adapted retain an article within the container, preferably by engaging the article, and an extended position at which the latch member permits removal of the article through the access aperture by being located out of the line of travel of an article as the article is withdrawn from the container; and
c. a locking member adapted to move from an operative position at which it retains the latch member in its retracted position and an inoperative position at which it permits extension of the latch member.
The invention also provides a container which is to contain one or more articles, which container has an access aperture through which the article(s) can be inserted into or removed from the container, provided with a detent mechanism of the invention mounted externally upon a wall of the container and adjacent to the access aperture of the container whereby the latch member is adapted to retain the article within the container when in its retracted position and to permit removal of the article through the access aperture when the latch member is in its extended position.
The invention can be applied to retaining a wide range of types of article within a wide range of shapes and sizes of container. However, the invention is of especial application in retaining a single generally rectangularly shaped article within a correspondingly shaped chamber within a container into which the article is a sliding fit through an open end face of the container. Thus, the invention is of use in retaining a book or similar article within a clear walled container so that the book is protected within the container and yet cannot be removed until the latch member is moved to its extended or inoperative position. For convenience, the invention will be described hereinafter in terms of a compact disc (CD) in its case to be retained within a clear plastic walled display container.
Preferably, the mounting member is provided in the form of a base plate or housing which is adapted to be located externally upon the container, for example by being welded, snap fitted or otherwise secured to the container. The base plate or housing is adapted to receive one or more of the other components of the detent mechanism and to secure them to the wall of the container adjacent the access aperture. The latch member is journalled for axial movement upon the base plate or within the housing. For example, the housing can carry internal guide ribs or projections which support the latch member laterally and guide the axial movement of the latch member. Preferably, the ribs or projections are formed so as to allow the distal end of the latch member to drop away from the container as the latch member is extended axially so that the distal end of the latch member is carried out of the line travel of an article as it is withdrawn from the container through the access aperture.
Accordingly, from one preferred aspect, the present invention provides a detent mechanism adapted to be mounted on a container which is to contain one or more articles, which container has an access aperture through which the article(s) can be inserted into or removed from the container, the detent mechanism being adapted to retain the article within the container, which detent mechanism comprises:
a. a plate member adapted to be located externally upon the container and adjacent the access aperture to the container so as to form part of, or to be mounted parallel to, a wall of the container;
b. a housing member carried by said plate member externally of the container;
c. a latch member carried by said housing and adapted to move axially externally of and substantially parallel to the plane of the said wall of the container between axially retracted and extended positions, said latch member having a recess intermediate the ends thereof and at at least the distal end thereof a stop member adapted to engage an article located within the container when the latch member is in its axially retracted position within the housing, the latch member being configured so that when the latch member is in its axially extended position the stop member is carried clear of the line of travel of the article as the article is withdrawn from the container; and
d. a biassed locking member adapted to move from an operative position at which it engages the said recess so as to retain the latch member in its axially retracted position and an inoperative position at which it permits axial extension of the latch member.
Alternatively, the base plate or the base of the housing can carry one or more upstanding lugs which engage co-operating slots or recesses in the under side of the latch member so that the latch member is slidably mounted by the inter-engagement of the lugs and slots or recesses. The engagement at the distal end of the latch member can be such that it disengages as the latch member is extended so as to allow the latch member to pivot and thus carry the distal end of the latch member clear of the withdrawal path of an article through the access aperture.
From another aspect, the present invention provides a detent mechanism which serves to retain an article within a container as described above, the detent mechanism comprising:
a. a latch member mounted on the exterior surface of one of the walls of the container in the vicinity of the access aperture, said latch member being capable of adopting a position to inhibit the removable of the article through the access aperture or a position to permit the removal of the article through the access aperture;
b. guide means for guiding the latch member for sliding and pivotable movement in relation to the said exterior wall of the container to move from one position to the other; and
c. a spring loaded locking member which is moveable between a locking position whereby movement of the latch member is restrained and a release position whereby movement of the latch member is permitted. Preferably, the guide means also provide the mounting means by which the latch member is mounted on the container.
It is within the scope of the present invention to form the mounting member or the lugs or other mountings for the latch member integrally with the wall of the container. For convenience, the invention will be described hereinafter in terms of a demountable detent mechanism rather than one which has part thereof formed integrally with the container.
Preferably, the latch member comprises an axially extending arm slidably journalled upon the mounting member or within the housing. The arm preferably carries or is formed with a transverse stop member at its distal end which extends into the path of travel of an article through the access aperture when the arm is in its retracted position and either bears against the article in the container or provides a stop which prevents withdrawal of the article. Where the latch member is slidably mounted upon upstanding lugs or the like, the arm preferably takes the form of an inverted channel member carrying the slots or recesses which are to engage the lugs in the inner base wall of the channel. When the lugs are engaged with the slots or recesses, the arm is secured to the base plate or the wall of the container by a bayonet type of mounting and the walls of the channel surround the mounting and prevent tampering with the mounting.
The movement of the arm from its retracted position to its extended position to release the article from the container is prevented by means of the locking member. Preferably, the locking member is a spring loaded stud which engages an appropriate recess, one of the stud or recess being carried by the latch member and the other by the mounting member. Thus, for example, the arm has a transverse recess into which a spring loaded stud carried by the mounting member or the housing locates when the arm is in the axially retracted position. Alternatively, the arm can carry the spring loaded stud and the mounting member or housing can have the recess into which the stud locates. Preferably, the pin is magnetic so that it can be withdrawn against the spring bias to release the arm for axial movement.
Preferably, the proximal end of the latch member is provided with a second stop member which engages the locking member or a co-operating stop carried by the mounting member so as to prevent excessive withdrawal of the latch member.
The detent mechanism can be mounted at any appropriate position on the container walls so that the stop carried by the latch member can obstruct the line of travel of an article as it is removed from the container. Typically, the detent mechanism will be mounted adjacent the base or top corner of the container and adjacent the access aperture. However, where the latch member is elongated, it may be possible to mount the detent mechanism at other locations on the container wall.
The detent mechanism of the invention can readily be made by extruding the component parts from a suitable plastic and securing them together by adhesive, sonic welding or any other suitable technique. In the case where the latch member is mounted upon the container or base plate by inter-engagement of lugs and slots or recesses as described above, such engagement can be a snap fit to prevent accidental separation of the latch member from the container or base plate and such a construction avoids the need for adhesive or welding, notably where the upstanding lugs are formed integrally with the wall of the container.
As indicated above, the detent mechanism can be made so that it forms an integral part during the manufacture of a security case for a CD disc, an audio or video tape or other article. However, the invention readily lends itself to the production of a standard detent mechanism which can then be adhered or otherwise secured to the base, side wall or top face of a standard display case to convert that case into a security case, thus avoiding the need to fabricate a specific security mechanism to fit a given case or to incorporate a security mechanism during the manufacture of the case.
DESCRIPTION OF THE DRAWINGS
A preferred form of the detent mechanism of the invention will now be described by way of illustration only with respect to the accompanying drawings in which
FIG. 1 is a diagrammatic side section of a security display container for a CD case incorporating one form of the detent mechanism of the invention;
FIG. 2 is a plan sectional view from below of the detent mechanism of FIG. 1;
FIG. 3 is a perspective view of a CD security case carrying another form of the detent mechanism of the invention with the detent mechanism in the axially extended position;
FIG. 4 is an exploded view of the detent mechanism of FIG. 3;
FIG. 5 is a vertical section through the detent machanism of FIG. 3 showing a partially engaged position of the lugs and slots of the mounting of the latched member;
FIG. 6 is a vertical section through the detent mechanism of of FIG. 3 showing a partially engaged position of the lugs and slots of the mounting of the latched member;
FIG. 7 is a vertical section through the detent mechanism of FIG. 3 showing a fully engaged position of the lugs and slots of the mounting of the latched member;
FIG. 8 shows the device of FIG. 3 with the latch member in the axially retracted position;
FIG. 9 shows an alternative form of the detent mechanism of FIG. 1 in the axially retracted position;
FIG. 10 shows an alternative form of the detent mechanism of FIG. 1 in the axially extended position;
FIG. 11 shows a magnetic device for releasing the locking member in the detent mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The container typically comprises a generally rectangular box having clear plastic or similar side walls 1 and an open end face 2 giving a closed ended rectangular chamber within the container. The side walls 1 can be solid or partially open so that the contents of the container can be inspected externally. The side walls can also carry magnetic or other labels which actuate an alarm system if the container is removed from the display or shop. The container is, apart from the detent mechanism, of conventional design and construction.
The container is dimensioned so that a case for a CD, shown dotted in FIGS. 1 and 2, is a sliding fit within the container. If desired, the container can be provided with a snap or clip on extension (not shown) so that the overall dimensions of the container thus formed can be axially enlarged to conform to the dimensions of the display rack.
The basal wall of the container adjacent the open front face is provided with a mounting plate 3 for the detent mechanism which is welded or otherwise secured to the container. As shown in FIG. 1, the mounting plate 3 and the detent mechanism can be provided as a separate retrofitted component which is welded or otherwise secured to the outer face of the basal wall of an existing container so that it lies parallel to but externally of the basal wall of the container. Alternatively, the detent mechanism can be incorporated into the container during the manufacture of the container. As shown in FIG. 1, the detent mechanism can extend for only part of the length of the wall on which it is mounted. However, as shown in FIGS. 9 and 10, it may be desired to provide greater areas of adhesive or welding contact between the detent mechanism and the container wall and to form the detent mechanism of the same length as the container wall. In this case, the base plate 3 may be omitted and the detent mechanism provided with a housing 4 which is welded along its basal periphery to the container as shown in FIGS. 9 and 10.
As shown in FIG. 1, the base plate 3 carries an external housing 4 which is dimensioned so that it slides within the transverse groove 24 of a magnetic release actuator device 20 as shown in FIG. 11 as used to withdraw the locking pins in present designs of container. Typically, such an actuator device comprises a base plate 21 having screw holes 22 by which it is secured to a worksurface (not shown). The base plate carries a circular magnet 23 having a transverse diametric groove 24 cut in it. When the housing 4 is inserted into the groove 24, the magnet 23 pulls the locking pin within the housing axially and releases the latch member in the detent mechanism. It is also preferred that the housing 4 corresponds in width to the width of the CD case or other article the container houses so that the housing can be mounted in existing article display systems.
The housing 4 is typically of a generally rectangular shape and has one open end face located adjacent the open end face of the container. Within the housing 4 is slidably journalled an arm which can move axially within the housing 4 from an axially extended position shown in FIG. 1 to an axially retracted position shown in FIG. 2. The distal end of arm 5 is provided with an upstanding stop member 6 which provides a transverse stop member which obstructs the removal of the CD case from the container when the arm 5 is in the axially retracted position as shown dotted in FIG. 1.
Preferably, arm 5 is formed with a bow so that as it is extended the distal end will droop as shown dotted in FIG. 1 to drop the stop member 6 out of the withdrawal path of the CD case. If desired, the side walls of the housing 4 can carry inwardly projecting ribs or the like which serve to locate and guide the movement of arm 5; or slots can be formed in the side walls into which transverse lugs carried by the arm 5 engage. However, as shown in FIG. 1, it is preferred to provide the under lip of the distal end of arm 5 with a tapering ramp member 7 which rides over the bottom lip of the open end of the housing to cause the arm 5 to rise as the arm is retracted into the housing. The ramp 7 can also be connected to the stop member 6 to impart rigidity thereto as shown in FIG. 1.
The arm 5 forms a sliding carrier for the stop member 6, to carry the stop member 6 in and out of the path of withdrawal of the CD from the container 1. The underside of arm 5 carried a recess 10 into which a pin 11 locates so as to prevent axial movement of the arm when in the axially retracted position. The recess 10 is conveniently formed as a cut out in an axial rib 12 on the underside of arm 5, the rib 12 imparting rigidity to the arm 5. The pin 11 is located within a sleeve 13 upstanding from the outer wall of the housing 4 and is biassed upwardly by a spring 14 located within the sleeve 13, pin 11 is retained in the sleeve by the arm 5 which in turn is a sliding fit against the underside of the inner face of the housing, which is preferably provided by the base plate 3. Arm 5 preferably carries a stop 15 at its proximal end, i.e. that end deepest into the housing, which butts against the upstand of sleeve 13 to prevent the arm 5 from being withdrawn excessively from the housing. It will be appreciated that the pin 11 and the spring 14 can be carried by the arm 5 and the pin can engage in a recess in the base wall of the container, the base plate 3 or the outer wall of the housing 4.
In use, the housing 4 is located in the slot 24 of the magnetic release device 20 which retracts pin 11 into the sleeve 13 and allows arm 5 to be axially extended to allow stop 6 to drop out of the line of travel of a CD case through the open and of the container. The CD case is inserted into the container and arm 5 is then axially retracted, for example by pressing the exposed end face of stop 6, until pin 11 engages the recess 10 on the underside of arm 5. Stop 6 engages the exposed front bottom corner of the CD case and prevents it from being withdrawn from the container until pin 11 is retracted by the magnetic release device 20 to allow arm 5 to be extended again.
As stated above, the detent mechanism comprising the sole plate 3, the housing 4, the arm 5 and stops 6 and 15, the sleeve 13 and pin 11 and spring 14 can all be formed as a separate assembly which is secured to the base of an existing container; or the detent mechanism can be incorporated into a container during manufacture of the container, in which case the sole plate 3 can form part or all of the container basal wall. Furthermore, as shown in FIGS. 9 and 10, the housing 4 can extend for the full length of the container wall, in which case the housing can incorporate one or more internal walls 16 to impart rigidity to the construction.
As shown in FIGS. 3, 4 and 8, a container 30 for storing a CD case 31, represented in dotted outline, is generally in the form of an open-sided rectangular box with continuous upper and lower walls 32, 33 and rear wall 34. A side strip 35 extends between walls 32, 33 adjacent an opening 36 at the front of the container 30 through which the CD case 31 can be inserted (arrow A, FIG. 3) or from which the CD case 31 can be withdrawn. At the same side, but spaced from the strip 35 so as to lie adjacent the rear wall 34, there are a pair of upper and lower flanges 37, 38. At the opposite side, the container 30 has further strips 39 extending between the upper and lower walls 32, 33 but adjacent the rear wall 34 and further walls defining a window 40 lined with a narrow edge strip 41. The side structures 35, 37, 38, 39, 40 serve to guide the CD case 31 laterally when it is being slid in or out of the container 30. Base feet 42 are provided beneath the lower wall 33 to permit the container 30 to be disposed in an upstanding display position. Adjacent the opening 36 there is a locking mechanism generally designated 43 which serves selectively to release and lock the article 11 within the container 10.
FIG. 3 shows the locking mechanism 43 in the open or released state when the CD case 31 can be freely introduced into the container in the direction of arrow A or withdrawn in the opposite direction. In contrast, FIG. 8 shows the locking mechanism 43 in the retention state where the CD case 31 is prevented from being withdrawn from the container 30.
The locking mechanism 43 is shown in more detail in FIGS. 4 to 7. The mechanism 43 comprises an L-shaped latching arm 44 with the minor arm of the L forming a dependent stop 45. The major arm of the L may have a partial U-shaped cross-section at least at the rear with a top wall 46 and side walls 47 which merge into the minor arm 45. As can be appreciated from FIGS. 3, 4 and 8, the minor arm 45 hooks and fits over an upper corner region of the CD case 31 when the CD case is locked into the container 30.
The L shaped latching arm 44 is mounted upon the container 30 by means of a pair of blocks 50, 51 which are mounted on top of the upper wall 32 of the container 30. These blocks can be secured to wall 32 by adhesive, welding or any other suitable means. Alternatively, the blocks 50 and 51 can be moulded integrally with the wall 32 during manufacture of the container
As shown in FIGS. 3 to 8, the rear block 51 has a forwardly projecting tongue 52 which slidably engages in recesses or slots 53 in the side walls 47 at the rear of the major arm of the L shaped latching arm 44. The tongue 52 adjoins an projection 54 at the rear of block 51 and the recesses 53 have enlarged angled and stepped portions 55 at their rear.
The front guide block 50 has a somewhat T-shaped side profile with tongues 56, 57 projecting forwardly and rearwardly respectively. The rearwardly projecting tongue 57 of the block 50 is somewhat narrower than the forwardly projecting tongue 56. A rectangular recess 58 in the forward portion of arm 44 is shaped to fit onto the tongues 56, 57 and a narrow slot 59 extends forwardly from recess 58 and is shaped to receive the forwardly projecting tongue 56 when the arm 44 is moved rearwardly with respect to wall 32. A blind bore 60 in the upper wall 32 of the container 30 is disposed between the blocks 50, 51 and receives a pin 61. A compression spring 62 is held in a complementary blind bore 63 in the arm 44 and acts to urge the pin 61 downwardly into the bore 60.
The arm 44 can be snap fitted onto the blocks 50, 51 with the spring 62 and the pin 61 trapped therebeneath during assembly. When fitted, the arm 44 can adopt one of three working positions depicted in FIGS. 5 to 7. In the locked or retaining position depicted in FIG. 7 the tongue 52 is fully engaged in the slots 53 and the rear wall 54 engages in the recessed portions 55 in the rear of arm 44 and lies flush or substantially flush with the rear face of the arm 44. The forward tongue 56 of the block 50 is likewise engaged in the slot 59. This prevents the arm 44 from being lifted clear from the upper wall 32 and the stop 45 provided by the short arm of the L prevents the CD case within the container 30 from being withdrawn. The pin 61 is engaged in the aligned bores 60, 63 and thus prevents axial movement of the arm 44.
To unlock the arm 44 and permit the release of the CD case 31, the container is inverted and the arm 44 placed into the groove 24 of the device 20 of FIG. 11. Pin 61 is attracted by the magnetic field fully into the bore 63 to compress the springe 62 and draw the pin out of the bore 60 in the wall 32 of the container 30. The arm 44 can now be moved axially forwardly with respect to the blocks 50 and 51 to adopt the forward position shown in FIG. 5 where the tongue 56 is released from the slot 59. The forward motion of the arm 44 can be accomplished by moving the CD case 31 forwardly to push on the stop 45 carried by arm 44. When the arm 44 has been moved forwardly, the plunger 61 is now supported on the wall 32 and the container 30 can be removed from the device 20. To release the CD case 31 from the container 30, the arm 44 is pivoted about the tongue 52 on the rear block 51 so that the stop 45 is lifted clear of the CD case 31 as shown in FIG. 6.
To insert a fresh CD case 31 into the container 30, the sequence is simply reversed so that from the open position of FIG. 6 the CD case 31 is inserted through the open face 36 of the container 30 and the arm 44 is swung down to engage on the top corner region of the CD case 31 as shown in FIG. 5. The CD case 31 and the arm 44 are then pushed rearwardly to relocate the arm 44 in the position shown in FIG. 7 when the pin 61 will re-engage in bore 60 in wall 32 to lock the arm in position.
The components of the container 30 including the locking mechanism 43, except for the pin 61 and the spring 62, can all be fabricated from injection moulded plastics material which may be transparent or translucent. It is also envisaged that, as known per se, the interior of the container 30 would be provided with a magnetic strip or the like which activates an alarm system if the CD case 31 is removed along with the container without proper authorization. | The present invention provides a detent mechanism adapted to be mounted on a container which is to contain one or more articles, notably CD cases, which container has an access aperture through which the article(s) can be inserted into or moved from the container. The detent mechanism is adapted to retain the article within the container and is formed from a mounting member adapted to be carried externally in the container, preferably at or adjacent the access aperture of the container. A latch member is adapted to be carried externally of the container by the mounting member and is movable between a retracted position at which at least the distal end of which is adapted to retain an article within the container. The latch member is also movable to a extended position in which latch member permits removal of the article through the access aperture by being located out of the line of travel of the article as the article is withdrawn from the container. A locking member, such as a spring loaded pin, is movable from an operative position at which it retains the latch member in its retracted position and an inoperative position in which it permits extension of the latch member. | 8 |
BACKGROUND OF THE INVENTION
(a) Field of the Invention:
The present invention relates generally to a pneumatic tool, and more particularly to a multi-purpose pneumatic tool.
(b) Description of the Prior Art:
There are numerous kinds of pneumatic tools using compressed air as power, such as air blow guns, tire chucks, stapling guns, etc. But, as is well known, these pneumatic tools generally have only a single function. One such pneumatic tool is shown in FIG. 1. A pneumatic stapling gun 99 is connected to an air hose 90 by means of a connector 91, and compressed air is conducted into the interior of the stapling gun 99 for use. However, there have been known at least the following drawbacks with such prior art:
1. As use of the connector 91 to associate the stapling gun 99 with the air hose 90 is to fixedly secure them both. Therefore, in use, the air hose 90 cannot revolve to match the jobs, and the connector 91 is also immovable. As a result, the air hose 90 may easily get entangled, causing inconvenience to the operator.
2. The connector 91 itself does not have other functions than as a means of connection. It often has to be replaced when serving for other purposes. Even in the case of air blow guns, it has to be mounted anew, which is very inconvenient indeed.
3. As the connector 91 has to be removed from or coupled to pneumatic tools in different jobs, the connector 91 will wear fast, which may result in air leakage and reduce the life of the connector 91.
4. Different pneumatic tools require different amount of air flow. As the air flow from the air hose 90 cannot be controlled, the components of the pneumatic tools may be easily damaged, affecting the life thereof.
SUMMARY OF THE INVENTION
Accordingly, a primary object of the present invention is to provide a multi-purpose pneumatic tool which has the advantages of extensive applications, convenience and good effects, thus eliminating the drawbacks with the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features and advantages of the present invention will be more clearly understood from the following detailed description and the accompanying drawings, in which,
FIG. 1 is a schematic view of a prior pneumatic tool;
FIG. 2 is an elevational, exploded view of the present invention;
FIG. 3 is a top plan view of the present invention in section;
FIG. 4 is a side plan view of the present invention in section;
FIG. 5(A) is a schematic view illustrating the present invention held by the palm of the operator;
FIG. 5(B) illustrates operation of the air blow gun according to the present invention;
FIG. 6 is a schematic view illustrating use of the tire chuck according to the present invention in inflation;
FIG. 7(A) is a schematic view illustrating rotation of the controlled mechanism according to the present invention; and
FIG. 7(B) is a schematic view illustrating rotation of the air blow gun according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIGS. 2, 3 and 4, the present invention essentially comprises a casing tool body 10, a control body 20, and a bolt assembly.
The casing 10 is substantially a circular structure having an air intake connector 11 disposed at its periphery. The air intake connector 11 is provided with a tapered screw hole 111 at its end and may be screwably locked with a connector 91 of an air hose 90. An axial through coupling hole 12 is formed at the center of the casing 10, and an air path 13 is formed connecting the screw hole 111 to the coupling hole 12.
The control body 20 is provided with a blind hole 201 of a suitable depth at the center of its bottom side. The end of the blind hole 201 is configured to have a screw hole 202 for screwably locked with the bolt assembly 30. An air regulator hole 203 and a control button hole 204 are respectively provided at opposite peripheral ends of the control body 20 for receiving an air regulator 21 and an air flow control button 22 respectively, the air regulator hole 203 and the control button hole 204 both pass through the blind hole 201. A first connector 205 and a second connector 206 are protrudently provided at opposite peripheral ends of the control body 20, respectively having a receiving hole 2051, 2061 of a suitable depth for receiving an air blow gun 24 and a tire chuck 23 respectively. The outer side of the first connector 205 is provided with a screw hole 2052 for receiving a screw 2053. The receiving hole 2051 of the connector 25 is connected to both the air regulator 203 and the control button hole 204 by respective ducts 28, 29. The receiving hole 2061 is connected to the coupling hole 12 by means of an air path 2062.
The above-mentioned air regulator 21 includes a locking sleeve 211 screwably clocked into the air regulator hole 203. The locking sleeve 211 in turn has a bolt 212 locked therein. The bolt 212 has one end projecting from the locking sleeve 211 with its extreme end screwably linked-up with a button 213 and the other end provided with a valve cock 214. A rear end of the valve cock 214 is provided with a ball cock 215, which will be caused by the button 213 to control the opening or closing between the air regulator hole 203 and the blind hole 201.
The air flow control button 22 includes a button body 221 having one end provided with a packing pad 222 and the other end provided with a receiving hole 2210, and has a push-button 225 linked to a valve rod 223 fitted with a spring 224. The valve rod 223 has a rear end provided with a valve cock 2231 which may close the button body 221. The control button 22 is screwably locked onto the control body 20.
The air blow gun 24 comprises a tubular body provided with an annular groove 241. A rear section of the tubular body is provided with a plurality of O-rings 242 and is screwably locked into the screw hole 2052 of the first connector 205 by means of a screw 2053, engaging the annular groove 241, thereby the air blow gun 24 is retained and prevented from slipping out of the first connector 205. The air blow gun 24 is coupled to the first connector 205 such that a suitable space is left between the first connector 205 and the rear section.
The tire chuck 23 includes a screw cap 233 and a valve rod 231. The valve rod 231 is disposed inside the receiving hole 2061 of the second connector 206. The valve rod 231 is fitted with a packing ring 232 and secured by the screw cap 233 locked into the receiving hole 2061. By means of the air inside the air path 2062, the valve rod 231 may urge against the packing ring 232 to achieve prevention of possible air leakage.
The bolt assembly 30 is provided with an air path 33 of a suitable depth at a rear section thereof. The rear section is provided with a plurality of external threads on its outer peripheral surface for engaging the screw hole 202 of the control body 20. The bolt assembly 30 further has an annular groove 31 disposed at a suitable position at a middle section thereof. A U-shaped ring 35 is disposed both above and below the annular groove 31. The annular groove 31 is provided with an air hole 32 passing axially through the air path 33. The bolt assembly 30 is assembled to the casing 10, which is in turn coupled to the control body 20. Both the casing 10 and the control body 20 may freely turn to match the free rotation of the air blow gun 24 so that they form a swivel connector capable of three-dimensional free rotation like a universal connector.
The operation and effects of the present invention will be described below with reference to the accompanying drawings.
OPERATION OF THE AIR BLOW GUN
With reference to FIGS. 5(A) and 5(B), the operator may use his/her palm 5 to directly hold the palm-sized control body 20 with his/her thumb 51 on the push-button 225 to control release of air. The other four fingers, on the other hand, grip the control body 20 to stabilize it and to prevent it from dropping during operation. To operate the air blow gun 24, it is only necessary to push the push-button 225 so that the valve cock 2231 of the valve rod 223 linked-up with the push-button 225 pushes into the control button hole 204 and compresses the spring 224 inside the receiving hole 2210, thereby compressed air is released and passes from the air hose 90 into the air path 13 of the casing 10 and, via the air hole 32 and air path 33 of the bolt assembly 30, into the blind hole 201 of the control body 20, where it continue to pass through the control button hole 204 via the air hole 2210 into the air path 28 to the air blow gun 24 for blowing purposes. At this point, both the air regulator 21 and the tire chuck 207 are closed, so that air can only flow out from the control button 22. As the control button 22 is an independent element, if it is damaged, it can be repaired or replaced conveniently.
OPERATION OF THE TIRE CHUCK
With reference to FIG. 6, to pump air into a tire 6, it is only necessary to align the tire chuck 23 provided on the control body 20 with an inflation valve 61 of the tire 6 so that a valve rod 62 of the tire 6 and the valve rod 231 of the tire chuck 23 presses against each other. The valve rod 231 will then retreat into the receiving hole 2061 and the valve rod 62 will also retreat into the inflation valve 61, so that there is a clearance between them, allowing air from the air path 2061 into the tire 6 to inflate the latter.
OPERATION OF THE SWIVEL CONNECTOR
For conventional pneumatic tools 4, it has been known that it is necessary to move or turn the tool to prevent the air hose 90 from getting entangled and that the operator has to bend his arm this way or that to operate the tool. Referring to FIGS. 7(A) and 7(B), the control body 20 is disposed on the casing 10 by means of the bolt assembly 30 so that the control body 20 may longitudinally rotate about 360° on the casing 10 with the bolt assembly 30 as center. Referring to FIG. 7(B), the air blow gun 24 is screwably locked into the first connector 205 using the screw 2053 and is retained by the annular groove 241 so that the air blow gun 24 may horizontally rotate about 360°. In addition, the invention may also allow the operator to achieve free rotation of a third dimension using the palm, i.e., using the elbow as the center of rotation. In this way, it is only necessary to rotate the control body 20 and the air blow gun 24 when operating the air blow gun 24. It is not necessary to bend or turn the arm and the air hose 90 through large angles during operation.
OPERATION OF THE AIR REGULATOR
Reference is made to FIG. 7(B). The air blow gun 24 is used in conjunction with the other pneumatic tools 4. But different pneumatic tools require different amount of air flow. The flow of compressed air must therefore be controlled. By means of adjusting the air regulator 21 to alter the clearance between the ball cock 215 and the air regulator hole 203 so as to control the air flow from the blind hole 201 to the air path 28, the amount of compressed air into the pneumatic tool 4 may be controlled so that different pneumatic tools 4 may achieve optimum performance and have longer life.
In summary, the present invention has the following advantages:
1. That the control body and the casing are mounted in a concentric manner on the bolt assembly allows free rotation and convenient operation.
2. The circular shape of the control body allows a best design of space to accommodate four most commonly used tools on a single body.
3. The arrangement of the air blow gun and the control button provides air blow effects like ordinary air blow guns.
4. The air regulator controls the amount of compressed air into the air blow gun or other pneumatic tools, preventing possible damage to the tool parts or the workpieces due to excessive compressed air flow.
5. The arrangement of the casing, the control body, and the air blow gun allows free rotation to make operation easy and convenient.
6. The tire chuck provided on the control body may be used for inflation purposes.
7. The present invention has multiple functions, in particular, the air blow gun may be used in conjunction with other pneumatic tools, eliminating the problem of changing connectors in the prior art.
8. The present invention is less costly to manufacture.
Although the present invention has been illustrated and described with reference to the preferred embodiment thereof, it should be understood that it is in no way limited to the details of such embodiment but is capable of numerous modifications within the scope of the appended claims. | A multi-purpose pneumatic tool combining the functions of an air blow gun, an air regulator, a tire chuck and a swivel connector includes a casing, a control body and a bolt assembly. The control body is provided with respective holes and connectors for screwably locking an air blow gun, a control body, a tire chuck and a control button. A bolt assembly couples the casing to the control body such that the control body and the casing may rotate freely with the bolt assembly as a pivotal center. The air blow gun may also perform free rotation along another axis. The multi-purpose pneumatic tool may also assembly to other tool to widen its applications. | 1 |
FIELD OF THE INVENTION
The present invention relates to clothes dryers. More particularly, the invention relates to a clothes dryer having a vacuum pump integral therewith to create sub-atmospheric pressures within the drum, thereby facilitating the drying of clothing and/or reducing the energy costs associated therewith.
BACKGROUND OF THE INVENTION
The desire for time and energy conservation has led to many useful developments of household appliances. In particular, a clothes dryer with an integral vacuum source has been proven to be more energy efficient that a conventional clothes dryer. A directly proportional relationship between temperature and pressure allows the evaporation temperature of the water in the clothing to be reduced as barometric pressure within the dryer is decreased. This phenomenon provides many advantages, including reduced drying times and temperatures as well as less damage to clothing.
In the past, others have taken advantage of this phenomenon in an attempt to produce a more efficient clothes dryer. For example, U.S. Pat. No. 5,724,750 issued Mar. 10, 1998 to Burress (“Burress”) discloses a clothes dryer with infrared heating and vacuum drying capabilities in which a stationary vacuum pump is capable of reducing the vacuum pressure inside the drum to a sub-atmospheric pressure. Likewise, U.S. Pat. No. 4,057,907 issued Nov. 15, 1777 to Rapino et al. (“Rapino”) details an apparatus having a vacuum pump that reduces the air pressure within a chamber, while a microwave emitter excites the water molecules. The apparatus of Burress and Rapino, however, each employ a rotating shaft and/or bearing assembly at their interface between internal regions of atmospheric and sub-atmospheric pressure.
Unfortunately, Applicant has found that the embodiments exemplified by the prior art are extremely difficult to implement. In order to obtain the tight seal necessary for maintaining the apparatus' internal vacuum, a soft bushing material, such as rubber or the like, must be utilized. Such a soft material, however, quickly wears, ultimately resulting in disintegration of the seal. On the other hand, hard materials that are impervious to wear are highly susceptible to tiny vacuum leaks, which in turn destroy the object of the invention.
It is therefore an overriding object of the present invention to provide a clothes dryer that incorporates vacuum assistance without the disadvantages inherent in the prior art. It is a further object of the present invention to provide such a clothes dryer that eliminates the need for a sealed bearing or rotating shaft extended between regions of atmospheric and sub-atmospheric pressure, thereby increasing the reliability of the appliance. Finally, it is an object of the present invention to provide such a clothes dryer that is economical to manufacture.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects, the present invention—a vacuum assisted dryer for accelerated drying of clothing—generally comprises a fixed frame, a rotatable drum within the fixed frame for holding and tumbling clothing within a vacuum sealable interior space, a vacuum source fixedly attached to the drum and a power delivery system for communicating electrical power from the fixed frame to the vacuum source on the drum. Preferably, the vacuum source comprises a vacuum pump and the power delivery system comprises a slip ring assembly about a spindle utilized to maintain the drum upon its axis of rotation inside the fixed frame.
In at least one embodiment, a plurality of heating pads are provided about the interior of the drum for imparting increased temperature to the clothing held therein, thereby further facilitating drying of the clothing. The heating pads may be conveniently located within paddles conventionally placed for the tumbling of clothing and may be powered through the same slip ring assembly as powers the vacuum source. A lint screen is also preferably interposed the vacuum source and the interior space of the drum, thereby preventing harm to the vacuum source from lint and the like.
The vacuum source exhausts to the interior space of the fixed frame, where moist air may be evacuated from the system with a blower assembly. The blower assembly maintains airflow from without the frame, about the interior of the frame and into and out of a duct to a conventional household dryer vent.
A vacuum relief for relieving vacuum pressure from within the drum is also preferably provided. Such a vacuum relief may comprises a valve in fluid communication with the interior space of the drum. In particular, Applicant has found suitable the use of a stopcock-type valve.
Finally, many other features, objects and advantages of the present invention will be apparent to those of ordinary skill in the relevant arts, especially in light of the foregoing discussions and the following drawings, exemplary detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the scope of the present invention is much broader than any particular embodiment, a detailed description of the preferred embodiment follows together with illustrative figures, wherein like reference numerals refer to like components, and wherein:
FIG. 1 shows, in a left side cross-sectional view taken through line 1 — 1 of FIG. 2, the vacuum assisted clothing dryer of the present invention;
FIG. 2 shows, in a top cross-sectional view taken through line 2 — 2 of FIG. 1, the dryer of FIG. 1;
FIG. 3 shows, in a front elevational cross-sectional view taken through line 3 — 3 of FIG. 1, the dryer of FIG. 1; and
FIG. 4 shows, in a top cross-sectional view taken through line 4 — 4 of FIG. 1; details of the drive mechanism and blower assembly of the dryer of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims appended hereto.
Referring now to the figures, the clothes dryer 10 of the present invention is shown to generally comprise a drum 20 rotatably enclosed within a fixed housing 11 . A vacuum pump 36 is utilized to reduce the atmospheric pressure within an interior space 28 of the drum 20 , thereby facilitating the drying of clothing held therein. As will be better understood further herein, the vacuum pump 36 is fixedly attached to and rotates with the drum 20 , which eliminates the requirement for vacuum sealed bearings and the like for communication of vacuum pressure to the interior space 28 of the drum 20 . This limitation eliminated, the clothes dryer 10 of the present invention is adapted to utilize principles of vacuum assisted drying without the high maintenance costs associated with the prior art.
As typical of currently available clothes dryers, the clothes dryer 10 of the present invention comprises a drum support system 45 for rotatably supporting the drum 20 within the fixed housing 11 . In particular, a plurality of rollers 46 are provided upon which the drum 20 rests. Additionally, however, provision is made in the present invention for maintaining the drum 20 on its axis of rotation. As shown in FIGS. 1 and 2, a vacuum door 22 through the front end 21 of the drum 20 is centrally fitted with a spherical bearing 25 for engaging a socket 16 at the distal end of a support arm 24 extending from an access door 13 through the front panel 12 of the fixed housing 11 . Similarly, a spindle 34 extending from the rear end 33 of the drum 20 engages a bearing 35 fixedly attached to the interior face of the rear panel 17 of the fixed housing 11 . As will be appreciated by those of ordinary skill in the art, the spherical bearing 25 engages the socket 16 in the axis of rotation of the drum 20 . Likewise, the spindle 34 engages the bearing 35 in the same axis of rotation, thereby cooperating with the spherical bearing 25 and socket 16 combination to retain the drum 20 within its axis of rotation upon the drum support system 45 . In this manner, as will be better understood further herein, delivery of electrical power from the fixed housing 11 to the rotating drum 20 is facilitated.
As previously discussed, a vacuum pump 36 is utilized to reduce the atmospheric pressure within the interior space 28 of the drum 20 . As also previously discussed, it is critical to the present invention to avoid sealed bearings, rotating shafts or the like between regions of subatmospheric atmospheric and pressure inside and outside, respectively, of the drum 20 . To this end, the vacuum pump 26 is dependently affixed directly to the drum 20 and rotates therewith. As particularly shown in FIG. 1, the vacuum pump 36 comprises a vacuum inlet 37 in fluid communication with the interior space 28 of the drum 20 through a provided vacuum line 39 . Preferably, the vacuum line 39 terminates in an exterior pocket 26 at the front end 21 of the drum 20 . In this manner, a lint filter 27 may be interposed the interior space 28 and the vacuum line 39 to the vacuum pump 36 , thereby preventing the introduction to the vacuum pump 36 of lint and/or other foreign objects.
Because, contrary to currently available vacuum assisted clothes dryers, the vacuum pump 36 of the present invention is directly affixed to the rotating drum 20 , it is necessary to deliver electrical power from the fixed housing 11 to the drum 20 for operation of the vacuum pump 36 . To this end, a power delivery system is implemented between a power source 41 (which my simply comprise the switched power from a conventional power cord 51 and electrical plug 52 ) on the fixed housing 11 and the drum 20 . According to the preferred embodiment of the present invention, a slip ring assembly 42 is implemented about the spindle 34 extending between the rear end 33 of the drum 20 and the fixed housing 11 . As is known to those of ordinary skill in the art, such a slip ring assembly 42 generally comprises a system of brushes 43 and rings 44 through which electrical power may be conveyed to a rotating object such as the drum 20 . Exemplary of the slip ring assemblies suitable for implementation of the present invention are those slip assemblies commercially available from the Airflyte Electronics Company of Bayonne, N.J. Because the rotating drum 20 is maintained in its axis of rotation as previously described, power delivery through the slip ring assembly 42 is easily within the ability of one of ordinary still in the art.
As in currently available clothes dryers, it is desirable to provide heat to the interior space 28 of the rotating drum 20 to facilitate drying of clothing held therein. Unlike currently available clothes dryers, however, the clothes dryer 10 of the present invention contemplates no airflow to or from the interior space 28 of the rotating drum 20 other than the vacuum pressure communicated through the vacuum line 39 from the vacuum pump 36 . As a result, the preferred embodiment of the present invention comprises a plurality of heating elements 30 distributed within the interior space 28 . Although those of ordinary skill in the art will recognize the many alternatives available, Applicant has found it convenient to locate the heating elements 30 on the interior faces of paddles 29 provided for tumbling of the clothing held within the interior space 28 .
While those of ordinary skill in the art will recognize the many substantial equivalents, Applicant has found suitable for implementation of the present invention the silicon rubber heater products commercially available from Watlow Columbia, Inc. of Columbia, Mo. Those products provide a reliable low-power source of heat at a temperature appropriate for use within the clothes dryer 10 with minimal risk for heat damage to the clothing held therein. As also will appreciated by those of ordinary skill in the art, the slip ring assembly 42 is readily adaptable for delivery of electrical power from the power source 41 to the heating elements 30 .
As is also typical of currently available clothes dryers, the clothes dryer 10 of the present invention must contend with the moisture removed from the drying clothing. In the present invention, however, the moisture evaporated from the drying clothing is removed from the interior space 28 of the rotating drum 20 through the vacuum pump 36 . In particular, an exhaust 38 from the vacuum pump 36 discharges water vapor into the interior of the fixed housing 11 . As a result, the preferred embodiment of the present invention comprises an exhaust blower 49 adapted to force air from within the fixed housing 11 through an exhaust duct 50 , which is preferably adapted for interface with a conventional household dryer vent. To ensure adequate air flow through the exhaust duct 50 for removal of the moist air within the fixed housing 11 an air intake grill 18 is preferably provided in the rear panel 17 of the fixed housing 11 , thereby ensuring a continuous volume of airflow. Additionally, in the preferred embodiment of the present invention, the exhaust blower 49 is operated by an electric drive motor 47 , which also preferably interfaces with and operates the drive assembly 48 rotating the drum 20 .
In order to ensure that the vacuum seal 23 about the vacuum door 22 may be broken for access to the interior space 28 of the drum 20 , a vacuum release 31 is preferably provided integral with the drum 20 . As will be appreciated by those of ordinary skill in the art, a valve 32 , which may be a stopcock valve, can economically perform this function. The user may then open the access door 13 by pulling the door 13 about its hinge 15 by a conventionally provided handle 14 . The support arm 24 is also hinged to the front panel 12 of the fixed housing 11 such that the vacuum release 31 may be accessed prior to opening of the vacuum door 22 .
While the foregoing description is exemplary of the preferred embodiment of the present invention, those of ordinary skill in the relevant arts will recognize the many variations, alterations, modifications, substitutions and the like as are readily possible, especially in light of this description, the accompanying drawings and claims drawn thereto. For example, conventional leveling glides 19 may be provided as shown in the figures. Likewise, the clothes dryer 12 of the present invention may be provided with an automatic shut-off switch integral with the access door 13 through the fixed housing 11 as well as a timer for conventional shut-off of the dryer. Additionally, those of ordinary skill in the art will recognize that it may be desirable to provide a counterweight 40 opposite the spindle 34 from the vacuum pump 36 for insuring balanced rotation of the drum 20 upon the drum support system 45 . In any case, because the scope of the present invention is much broader than any particular embodiment, the foregoing detailed description should not be construed as a limitation of the scope of the present invention, which is limited only by the claims appended hereto. | A vacuum assisted dryer for accelerated drying of clothing generally comprises a fixed frame, a rotatable drum within the fixed frame for holding and tumbling clothing within a vacuum sealable interior space, a vacuum pump fixedly attached to the drum and a power delivery system for communicating electrical power from the fixed frame to the vacuum source on the drum. The power delivery system comprises a slip ring assembly about a spindle utilized to maintain the drum upon its axis of rotation inside the fixed frame. A plurality of heating pads are provided about the interior of the drum to facilitate drying of the clothing. A blower assembly evacuates to a conventional dryer vent moist air exhausted from the vacuum pump. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a multiple magnetic pump system in which driving force is magnetically transmitted to an impeller.
2. Description of the Related Art
FIGS. 1 and 2 show in combination a conventional magnetic pump 10, disclosed in, for example, Japanese Utility Model Publication No. 20340/1970, which is employed to pump a processing liquid used in a photographic developing apparatus.
The pump 10 is arranged such that a driving magnetic material 16 which is secured to a driving shaft 14 of a motor 12 rotates around the outer periphery of a partition tubular member 15 provided in a casing 26 to drive a driven magnetic material member 20 buried in an impeller 18 located in a pump chamber 17 so that the impeller 18 is rotated. A lubricating member 19 which also serves as a spacer is disposed between the outer periphery of the impeller 18 at which the driven magnetic material member 20 is positioned and the inner periphery of the tubular member 15 for the purpose of enabling the impeller 18 to rotate smoothly. The rotation of the impeller 18 causes a processing liquid to be sucked in from an inlet port 22 provided on the prolongation of the axis of the driving shaft 14, the processing liquid then being discharged from an outlet port 24 by means of centrifugal force.
In the pump 10 having such a structure, the motor 12 and the pump chamber 17 are shut off from each other by the tubular member 15 provided in the casing 26 so that no processing liquid in the pump chamber 17 leaks out.
Since a photographic developing apparatus is generally provided with a plurality of processing tanks for containing, for example, a developer, a fixer, water for rinsing and so forth, it is necessasry to provide a number of pumps 10 corresponding to the number of the processing tanks. In the pump 10 with the above-described structure, however, the inlet port 22 is provided on the prolongation of the axis of the driving shaft 14 of the motor 12, and this permits only one pump 10 to be provided for a single motor 12. Accordingly, it is necessary to provide a number of motors 12 corresponding to the number of required pumps 10.
SUMMARY OF THE INVENTION
In view of the above circumstances, it is a primary object of the present invention to provide a multiple magnetic pump system which is so designed that a plurality of pumps can be activated by the operation of a single motor.
According to the present invention, the above object can be accomplished by a multiple magnetic pump system comprising: a plurality of casings each defining a pump chamber; a pair of inlet and outlet ports provided in the pump chamber; an impeller rotatably supported in the pump chamber and having a driven magnetic material member; and a driving magnetic material member connected to a driving source so as to drive the impeller via the driven magnetic material member, characterized in that there is provided a single driving shaft of the driving source, that each pump chamber has a tubular member which defines a through hole therein and partitions the through hole from the pump chamber so as to allow the single driving shaft to be inserted into each through hole of the plurality of casings, and that the impeller is rotatably mounted on each tubular member.
In the above arrangement, the respective through holes of the plurality of casings are aligned on the same axis. Thus, it is possible for all the driving magnetic material members disposed on the same axis to transmit driving force to the corresponding driven magnetic material members diposed in the respective pump chambers defined inside the casings.
Since the driven magnetic material members are provided on the respective impellers, the driving magnetic material members cause the corresponding impellers to rotate via the driven magnetic material members. In consequence, centrifugal force is produced in each pump chamber. This centrifugal force causes each processing liquid to be sucked in from the inlet port of the corresponding pump and discharged from the outlet port.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present invention will become more apparent from the following description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, in which like reference numerals denote like elements, and in which:
FIG. 1 is a front elevational view of a conventional magnetic pump;
FIG. 2 is a sectional view taken along the line II--II of FIG. 1;
FIG. 3 is a perspective view of a first embodiment of the multiple magnetic pump system according to the present invention;
FIG. 4 is an exploded perspective view of the motor and the first pump employed in the first embodiment;
FIG. 5 is a front elevational view of the first embodiment of the multiple magnetic pump system according to the present invention;
FIG. 6 is a sectional view taken along the line VI--VI of FIG. 5;
FIG. 7 is a perspective view of a second embodiment of the multiple magnetic pump system according to the present invention;
FIG. 8 is an exploded perspective view of the second embodiment shown in FIG. 7;
FIG. 9 is a front elevational view of the second embodiment of the multiple magnetic pump system according to the present invention; and
FIG. 10 is a sectional view taken along the line X--X of FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 3 and 4 show in combination a multiple magnetic pump system 28 in accordance with a first embodiment of the present invention.
The multiple magnetic pump system 28 includes a plurality of pumps, including first and second pumps 30 and 32, which are operably connectable to a motor 34. It is to be noted that the second pump 32 is not shown in FIG. 4.
A ring-shaped flange 36 is secured to the motor 34 so that the center of the flange 36 coincides with the axis of a driving shaft 38 of the motor 34. Four parallel relatively long bolts 40 (two of them are not shown) project from the flange 36 for the purpose of mounting the pumps 30 and 32. A driving magnetic material member 42 is rigidly fitted on the driving shaft 38 of the motor 34.
The first pump 30 has a casing 48 formed from a base member 44 and a cover member 46, and an impeller 50. The base member 44 and the cover member 46 are each made of a plastic material and formed such as to have a dish-like configuration. The base and cover members 44 and 46 are connected together so that their respective indented sides face each other, whereby a pump chamber 51 (see FIG. 6) is defined inside the casing 48. When the base and cover members 44 and 46 are connected together, two pins 52 provided on the base member 44 are respectively fitted into two pin receiving holes 54 provided in the cover member 46, whereby the base and cover members 44 and 46 are accurately positioned relative to each other. Further, an O-ring 56 formed of an elastic material is disposed at a part of the area of contact between the respective abutment surfaces of the base and cover members 44 and 46 so that the airtightness of the interior of the pump chamber 51 is enhanced.
A thin-walled tubular member 58 is provided at the axial center of the base member 44 so as to project toward the cover member 46. A circular bore 60 having an inside diameter substantially equal to the inside diameter of the tubular member 58 is provided at the axial center of the cover member 46. Thus, when the base and cover members 44 and 46 are connected together, a through hole 62 is defined by the tubular member 58 and the circular bore 60, the through hole 62 being partitioned from the pump chamber 51. The tubular member 58 is integrally molded with the base member 44. The distal end portion of the tubular member 58 is fitted into a ring-shaped groove (not shown) provided along the circumference of the circular bore 60 of the cover member 46, whereby the through hole 62 and the pump chamber 51 is isolated from each other.
The impeller 50 is disposed on the outer periphery of the tubular member 58, that is, within the pump chamber 51, through a lubricating member 64 for enabling the impeller 50 to rotate smoothly. The lubricating member 64 is formed from a thin sheet of a synthetic resin such as Teflon and is bent in a cylindrical shape when disposed between the outer periphery of the tubular member 58 and the inner periphery of the impeller 50. A driven magnetic material member 66 is buried in the impeller 50 (see FIG. 6) so as to receive driving force from the driving magnetic material 42 member. The impeller 50 is rotated by the driving force transmitted thereto via the driven magnetic material member 42, thus causing centrifugal force within the pump chamber 51.
As also shown in FIGS. 5 and 6, a first communicating pipe 68 which is communicated with the pump chamber 51 is connecting to the base member 44 so as to extend tagentially with respect to the pump chamber 51, thereby providing an outlet port 70. A second communicating pipe 72 which is communicated with the pump chamber 51 is connected to the cover member 46 so as to extend tangentially with respect to the pump chamber 51, thereby providing an inlet port 74.
Four bores 76 are provided in the peripheral wall of the casing 48 defined by the respective peripheral walls of the base and cover members 44 and 46 when connected together. The aforementioned bolts 40 are respectively inserted into these bores 76, whereby the respective through holes of the first and second pumps 30 and 32 can be disposed on the same axis, and the first and second pumps 30 and 32 are secured to the flange 36 by means of the bolts 40 and nuts (not shown).
If the length of the bolts 40 is increased, it becomes possible to mount a correspondingly increased number of pumps.
The following is a description of the operation of the above-described embodiment.
Although the multiple magnetic pump system in accordance with this embodiment has two pumps, that is, the first and second pumps 30 and 32, the operation of the first pump 30 alone will be described hereinunder.
As the motor 34 rotates, the driving magnetic material member 42 provided on the driving shaft 38 rotates. Since the driving magnetic material member 42 is inserted into the through hole 62 of the casing 48, the driving force from the driving shaft 38 is magnetically transmitted to the driven magnetic material member 66 located within the pump chamber 51, thus causing the impeller 50 to rotate inductively. The rotation of the impeller 50 generates centrifugal force in the liquid within the pump chamber 51, and this causes new liquid to be sucked into the pump chamber 51 from the inlet port 74. The liquid within the pump chamber 51 is centrifugally accelerated and delivered toward the outlet port 70 along the inner peripheral wall of the pump chamber 51. Since the outlet port 70 is provided so as to be tangential with respect to the pump chamber 51, the liquid is smoothly discharged from the outlet port 70 by means of the centrifugal force.
Accordingly, the impeller 50 in the pump chamber 51 continuously rotates in response to the rotation of the motor 36, and the liquid is thereby continuously pumped in and out by means of the centrifugal force.
If a plurality of pumps, including the second pump 32 with the same configuration as the first pump 30, are disposed so that the respective through holes 62 are aligned on the same axis, it is possible to produce centrifugal force in the liquid within each pump chamber 51 by means of the driving force transmitted from the driving magnetic material member 42. In this case, it is preferable to additionally provide driving magnetic material members 42 on the driving shaft 38 in correspondence with the number of added pumps.
It is to be noted that since each driving magnetic material member 42 and the corresponding pump chamber 51 are partitioned from each other by the associated tubular member 58 and driving force is magnetically transmitted, there is no risk of the liquid within the pump chamber 51 leaking out. As has been described above, the multiple magnetic pump system according to the present invention includes a plurality of casings each provided with a through hole which allows a driving magnetic material member to be inserted thereinto, so that it is possible to activate a plurality of pumps by the operation of a single motor.
Referring next to FIG. 7, there is shown a multiple magnetic pump system 128 in accordance with a second embodiment of the present invention in which two magnetic pumps are provided for one driving magnetic material member.
The multiple magnetic pump system 128 includes a motor 130 which serves as a driving means and which has a flange 132 secured to the outer periphery thereof. The motor 130 is secured to a given base by rigidly fastening the flange 132 to the base by bolts or other fastening means (not shown). A ring-shaped flange 136 is secured to the end face of the motor 130 on the side thereof from which a driving shaft 134 projects. The center of the flange 136 is coincident with the axis of the driving shaft 134.
As shown in FIG. 8, four through holes 140 are provided in the flange 136 so as to extend from one end face to the other end of the flange 136. One of each of the relatively long bolts 142 is fitted into the corresponding through hole 140. An external thread 144 is formed on the other end portion of each of the bolts 142. A disk-shaped driving magnet 146 which serves as a driving magnetic material member is rigidly fitted on the longitudinally central portion of the driving shaft 134 of the motor 130. In consequence, as the driving shaft 134 of the motor 130 rotates, the driving magnet 146 rotates together with the driving shaft 134 in one unit. Thin-walled spacers 148 made of a material with a relatively low coefficient of friction are respectively disposed on both faces of the driving magnet 146. Two magnetic pumps 150 are respectively installed on both sides of the driving magnet 146 across the corresponding spacers 148. It is to be noted that FIG. 8 shows only the spacer 148 and the magnetic pump 150 on the left-hand side of the driving magnet 146, and the spacer 148 and the magnetic pump 150 on the right-hand side of the magnet 146 are not shown for the purpose of simplifying the illustration.
Each of the magnetic pumps 150 has a casing 152 composed of a base member 160 and a cover member 162. The respective peripheral edges 160A and 162A of the members 160 and 162 on their indented sides are brought into close contact with each other so that a pump chamber 158 is defined inside the casing 152. A circular bore 154 is provided in the center of the cover member 162 of the casing 152. A tubular member 156 is provided at the center of the base member 160, that is, on the same axis as the bore 154, so as to project toward the cover member 162. Thus, one through hole is defined by the tubular member 156 and the bore 154 when connected together, and the driving shaft 134 extends through this through hole. The pump chamber 158 is isolated from the through hole by the tubular member 156.
An O-ring 164 is disposed in the area of the contact between the peripheral edge 160A of the base member 160 and the peripheral edge 162A of the cover member 162. The distal end portion of the tubular member 156, which is integrally formed with the base member 160, is fitted into a groove (not shown) formed in the cover member 162, whereby the pump chamber 158 is hermetically sealed.
Each of the peripheral edges 160A and 162A has a relatively large wall thickness and is provided with circular bores 165 for respectively receiving the bolts 142. More specifically, a plurality of magnetic pumps 150 are integrally secured to the motor 130 in such a manner that the driving shaft 134 of the motor 130 is rotatably inserted into the respective through holes of the casings 152 of the pumps 150, while the bolts 142 are inserted into the respective bores 165, and the nuts (not shown) are screwed onto the external threads 144.
Through holes are respectively provided in the outer peripheries of the base and cover members 160 and 162, and tubular pieces are formed at the respective through holes so as to project tangentially with respect to the pump chamber 158, thereby providing an outlet port 166 and an inlet port 167, respectively, for a processing liquid.
An impeller 168 is disposed within the pump chamber 158 and is rotatably supported by the outer periphery of the tubular member 156 through a lubricating member 170 for allowing the impeller 168 to rotate smoothly. The lubricating member 170 is formed from a thin sheet of a synthetic resin such as Teflon and is bent in a cylindrical shape when disposed beween the outer periphery of the tubular member 156 and the inner periphery of the impeller 168. The impeller 168 has a rotary base 172 and a plurality of vanes 174, described hereinafter. The rotary base 172 is composed of a tubular portion 176 rotatably supported on the outer periphery of the tubular member 156, and a disk portion 178 integrally secured to one end face of the tubular portion 176. The rotary base 172 is so disposed that the disk portion 178 faces the driving magnet 146 across the side wall of the cover member 162. A disk-shaped driven magnet 180 which serves as a driven magnetic material is buried in the disk portion 178. The driven magnet 180 is magnetically rotated in response to the rotation of the driving magnet 146.
One end of each of a plurality of vanes 174 extending radially of the tubular portion 176 is secured to the outer periphery of the tubular portion 176 at equal spacings. The intermediate portion of each vane 174 is circularly bent and has a width gradually reduced toward the distal end of the vane 174. One lateral edge of each vane 174 is secured to the disk portion 178.
When the impeller 168, formed as described above, is rotated by virtue of the magnetic attraction force acting between the driving magnet 146 and the driven magnet 180, centrifugal force is generated in the processing liquid within the pump chamber 158. In other words, in response to the rotation of the impeller 168, new processing liquid is sucked in from the inlet port 167 and is delivered to the outlet port 166 along the inner peripheral wall of the pump chamber 158.
In this embodiment, two magnetic pumps 150 are disposed so as to respectively face both end faces of the driving magnet 146, and the disk portion 178 of the impeller 168 of each pump 150 is disposed on the side of the pump 150 which is closer to the driving magnet 146. It is therefore possible for the two magnetic pumps 150 to be simultaneously driven by the operation of a single driving magnet 146.
The following is a description of the operation of the second embodiment.
As the driving shaft 134 of the motor 130 rotates, the driving magnet 146 rotates. Since the spacer 148 with a relatively small coefficient of friction is disposed between the driving magnet 146 and the casing 152 of each pump 150, the driving magnet 146 can rotate smoothly.
The impellers 168 are rotatably supported on the respective tubular members 156 within the pump chambers 158 of the two magnetic pumps 150 so that the disk portions 178 face the driving magnet 146. Accordingly, the driving magnet 146 can apply magnetic attraction force to both the driven magnets 180, so that the driving force from the driving shaft 134 can be transmitted to the two impellers 168.
Each impeller 168 is smoothly rotated by virtue of the corresponding lubricating member 170, and the rotation of the impeller 168 causes centrifugal force to be generated in the pump chamber 158. This centrifugal force causes new processing liquid to be sucked in from the inlet port 167 and delivered to the outlet port 166 along the inner peripheral surface of the pump chamber 158. Since the outlet port 166 is extended tangentially with respect to the inner peripheral surface of the pump chamber 156 and in the direction of the flow of the processing liquid, the liquid is smoothly discharged. In other words, when the impeller 168 continuously rotates in response to the rotation of the driving shaft 134, the processing liquid is continuously pumped in and out.
Further, the pump chamber 158 through which the processing liquid passes is hermetically sealed except for the outlet port 166 and the inlet port 167 by employing the O-ring 164 or the like which seals the joint between the base and cover members 160 and 162, and the impeller 168 in each pump chamber 158 is magnetically rotated. There is therefore no risk of the processing liquid leaking out from the pump chamber 158. In addition, since the processing liquid is isolated from the driving shaft 134 and the motor 130, there is no adverse effect on the processing liquid.
Further, in this embodiment, the driving magnetic pump disposed so as to face the end face of the magnetic pump 150. Accordingly, unlike the first embodiment in which a driven magnet is buried in the tubular portion 176 and a driving magent is disposed in the through hole, it is possible according to the second embodiment to carry the driving shaft 134 in such a manner that it is rotatably supported directly by the through hole. It is therefore possible to reduce the diameter of the driving shaft 134.
Although in this embodiment two magnetic pumps 150 are provided for on driving magnet 146 and disposed so as to respectively face both end faces of this driving magnet 146, three or more magnetic pumps 150 may be provided. In such a case, as shown by the imaginary line in FIG. 10, another driving magnet is additionally disposed between the second and third magnetic pumps, and the driven magnet 80 of the impeller 168 of the third magnetic pump is disposed so as to face the second driving magnet.
Alternatively, another set of the multiple magnetic pump system such as that shown in FIG. 8 in which two magnetic pumps are provided for one driving magnet may be mounted on an extended driving shaft.
Further, the outlet and inlet ports 166 and 167 may be provided at any position on the outer periphery of the casing 152. | A multiple magnetic pump system comprises a plurality of pump chambers; a pair of inlet and outlet ports provided in each of the pump chambers; an impeller rotatably supported in each of the pump chambers and having a driven magnetic material; and a driving magnetic material connected to a driving source so as to drive the impeller via the driven magnetic material. There is provided a single driving shaft of the driving source, and each of the pump chambers has a tubular member which defines a through hole therein and partitions the through hole from the pump chamber so as to allow the single driving shaft to be inserted into each of the through hole of the plurality of casings. The impeller is rotatably mounted on each of the tubular members. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a process for the preparation of the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt which is largely free from impurities.
BACKGROUND OF THE INVENTION
[0002] The preparation of the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is known per se (DE A 440 96 89). The process can be explained by the following equation:
[0003] Phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is then carried out at a temperature of about 120° C. at a reaction time of one hour. Hydrolysis in ice water is then carried out, phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt crystallizing out; the crystallizate is filtered off. The still moist crystallizate is then taken up and dissolved in an alkaline hydroxide solution, such as sodium hydroxide solution, then treated with activated carbon and heated. The activated carbon is filtered off, and the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is precipitated out by adding sulfuric acid. Drying gives pulverulent phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt with a purity of 99% by weight.
[0004] During the performance testing of the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt prepared in this way, it is found that the use of this product prepared in accordance with the above process leads to unacceptable discolorations in the formulations.
[0005] A cause of the discolorations are, inter alia, diphenylamine, 3,4-diamino-benzenesulfonic acid and 2-(4′-carboxy-phenyl)-benzimidazole-6-sulfonic acid.
SUMMARY OF THE INVENTION
[0006] An object of the present invention is the preparation of phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt in high purity which, in particular, does not contain any discoloring components.
[0007] We have found a process for the preparation of phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt by reacting o-phenylenediamine with terephthalic acid and chlorosulfonic acid in the presence of strong acids, which is characterized in that the reaction time is 10 to 15 hours.
DETAILED DESCRIPTION OF THE INVENTION
[0008] The process according to the present invention gives phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt in a purity greater than 98% by weight. By-products are merely
[0009] The by-products are safe and cause no discoloration of the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt.
[0010] The preferred reaction time for the process according to the present invention is 11 to 12 hours.
[0011] In a preferred embodiment of the process according to the present invention, the phenylene-bis-benzimidazole-tetrasulfonic acid obtained in the reaction or after hydrolysis is, in a first step, dissolved in water and treated with activated carbon, which is then separated off, and where the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is precipitated out of the filtrate with sodium chloride and separated off, and, in a second step, is again dissolved in water and sodium hydroxide solution and again treated with activated carbon, which is then again separated off, where pure phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt precipitates out of the filtrate by acidification and is then optionally also purified.
[0012] The phenylene-bis-benzimidazole-tetrasulfonic acid obtained in the reaction or after hydrolysis is dissolved in the first step in water in the temperature range from 40 to 80° C., preferably 45 to 55° C..
[0013] Preference is given here to preparing a 1 to 30% by weight, preferably 5 to 7% by weight, solution of phenylene-bis-benzimidazole-tetrasulfonic acid.
[0014] Activated carbon for the process according to the present invention (first and second step) can be all commercially available types.
[0015] To precipitate out the sodium salt, a 1 to 15, preferably 3 to 10, equimolar amount of sodium chloride is generally added.
[0016] The phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt obtained in the first step is dissolved in the second step in water in the temperature range from 30 to 80° C., preferably from 45 to 50° C.
[0017] Preference is given here to preparing a 5 to 25% by weight, preferably 15 to 20% by weight, solution of phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt.
[0018] The phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt obtained in the first step is dissolved and, after treatment with and removal of the activated carbon, precipitated out by acidification to about pH 3. The acidification is preferably carried out using hydrochloric acid. Surprisingly, the disodium salt precipitates out here as well.
[0019] The phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt obtained in the second step can be washed again with phosphoric acid in a preferred embodiment.
[0020] The process according to the present invention can be carried out, for example, as follows:
[0021] Sulfuric acid, terephthalic acid and o-phenylenediamine are initially introduced and the mixture is heated to, for example, 110° C. under a nitrogen atmosphere. Then, over the course of 4 h, chlorosulfonic acid is metered in at a temperature between 110 and 120° C., and then the mixture is further stirred for 12 h. The phenylene-bis-benzimidazole-tetrasulfonic acid obtained after hydrolysis is dissolved at 35-40° C. in water, treated with activated carbon and stirred for about 30 min at the same temperature. The activated carbon is filtered off, and the filtrate is admixed with sodium chloride and slowly cooled to room temperature with stirring over the course of about 2 hours for precipitation. The resulting phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is then filtered off and after-washed with 5 percent strength sodium chloride solution.
[0022] The resulting phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is again introduced into water and, for dissolution, 45 percent strength sodium hydroxide solution is added to a pH of 5, then activated carbon is added again. The mixture is maintained at 55° C. and stirred for about 2 hours. The activated carbon is separated off and the filtrate is acidified with pure hydrochloric acid to pH 3 to precipitate out the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt again. The mixture is stirred for about 2 hours and cooled to room temperature. The phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is separated off in a manner known per se, e.g. by filtration.
[0023] The resulting phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt can then also be washed with a 2% by weight aqueous sodium chloride solution which has been adjusted to pH 3 using small amounts of phosphoric acid; drying is then carried out, for example, at 140° C. and 2 mbar.
[0024] Use of the process according to the present invention gives a product which is analytically perfect in the trace region, which is best suited for use in cosmetic formulations and does not have the discoloration disadvantages detailed in the introduction. Surprisingly, the presence of problematical trace components is prevented.
[0025] Phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt can be used as UV-A filters in cosmetic products.
EXAMPLE
[0026] 1,703 g of sulfuric acid, 96% are initially introduced and 232 g of terephthalic acid are introduced, then, after the system has been flushed with nitrogen, 302 g of o-phenylenediamine are added in portions, which causes the temperature to increase to 97° C. The temperature is then increased to 110° C. 2,200 g of chlorosulfonic acid are then metered in over the course of 4 h, the temperature being maintained between 1 10-120° C., and, after the metered addition, the mixture is stirred for a further 12 h at said temperature.
[0027] The reactor contents are cooled to room temperature, and 4,000 g of water at 5° C. are metered in over the course of 4 h, which causes the temperature to increase to about 47° C., then the mixture is after-stirred for a further 2 h and then filtered, giving 1,200 g of moist phenylene-bis-benzimidazole-tetrasulfonic acid.
[0028] This press cake is introduced into 11,000 g of water at 40° C. and dissolved, then 30 g of activated carbon are added. The mixture is stirred for 30 min under nitrogen and then filtered. The filtrate is admixed at 50° C. with 600 g of sodium chloride and stirred for 2 h at this temperature, the temperature being reduced to 25° C. towards the end of the stirring period; and then the mixture is filtered. The resulting product is washed with 2,800 g of 5% by weight sodium chloride solution, giving 1,362 g of phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt.
[0029] The resulting phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is introduced into 4,500 g of water at 50° C. and suspended (pH 2.4); then, at 50° C., 168 g of 45 percent strength sodium hydroxide solution is added to adjust the pH to 5 and to dissolve the product, then 30 g of activated carbon are added, the mixture is heated to 55° C. and after-stirred for 2 h and filtered, the filtrate is treated with 162 g of pure hydrochloric acid, then the temperature is maintained at 50° C. and a pH of 3 is adjusted, the mixture is stirred for 2 h under nitrogen and cooled to 25° C.; the mixture is then filtered and the filter cake is then washed with 4,000 g of 2 percent strength sodium chloride solution which has been adjusted to pH 3 using a small amount of phosphoric acid, giving 1,155 g of the thus purified phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt.
[0030] The thus purified phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt is then dried for 10 h at 140° C. and 2 mbar, giving 700 g of end-product (residual moisture 2%). The resulting phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt has a purity of 98% by weight and comprises as by-products merely
[0031] The by-products are safe and cause no discoloration of the phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt.
[0032] Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims. | Phenylene-bis-benzimidazole-tetrasulfonic acid disodium salt which is largely free from impurities can be prepared by reacting o-phenylenediamine with terephthalic acid and chlorosulfonic acid in the presence of strong acids with a reaction time of 10 to 15 hours. | 2 |
FIELD
[0001] The subject matter herein generally relates to a device and a method for monitoring people, and a method for monitoring and counting people.
BACKGROUND
[0002] To monitor a plurality of persons, their individual features can be established and the individual people tracked.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] Implementations of the present technology will now be described, by way of example only, with reference to the attached figures.
[0004] FIG. 1 is a block diagram of an embodiment of a monitoring device of the present disclosure.
[0005] FIG. 2 is a schematic diagram of an embodiment of an extracting module of the monitoring device in FIG. 1 .
[0006] FIG. 3 is another schematic diagram of the embodiment of the extracting module in FIG. 2 .
[0007] FIG. 4 is a schematic diagram of an embodiment of a first process of a computing module of the monitoring device in FIG. 1 .
[0008] FIG. 5 is a schematic diagram of a second process of the computing module in FIG. 4 .
[0009] FIG. 6 is a schematic diagram of a third process of the computing module in FIG. 4 .
[0010] FIG. 7 is a schematic diagram of a fourth process of the computing module in FIG. 4 .
[0011] FIG. 8 is a schematic diagram of a fifth process of the computing module in FIG. 4 .
[0012] FIG. 9 is a schematic diagram of a sixth process of the computing module in FIG. 4 .
[0013] FIG. 10 is a schematic diagram of a seventh process of the computing module in FIG. 4 .
[0014] FIG. 11 is a schematic diagram of an eighth process of the computing module in FIG. 4 .
[0015] FIG. 12 is a schematic diagram of an embodiment of the monitoring device for counting people.
[0016] FIG. 13 is a schematic diagram of an embodiment of the monitoring device for counting people.
[0017] FIG. 14 is a flow chart of an embodiment of a monitoring method of the present disclosure.
[0018] FIG. 15 is a flow chart of an embodiment of a counting method of the present disclosure.
DETAILED DESCRIPTION
[0019] It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.
[0020] Several definitions that apply throughout this disclosure will now be presented.
[0021] The term “coupled” is defined as connected, whether directly or indirectly through intervening components, and is not necessarily limited to physical connections. The connection can be such that the objects are permanently coupled or releasably coupled. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like.
[0022] The disclosure will now be described in relation to a monitoring device.
[0023] FIG. 1 illustrates a monitoring device 100 .
[0024] The monitoring device 100 can comprise a storing module 10 , an extracting module 11 , a computing module 12 , and a signal acquisition module 13 .
[0025] The signal acquisition module 13 is configured to provide a first signal of image or video.
[0026] In one embodiment, the signal acquisition module 13 can comprise a camera.
[0027] In one embodiment, the signal acquisition module 13 may get the first external signal.
[0028] The storing module 10 is configured to store personal information of persons to be monitored. The personal information can comprise color information.
[0029] The extracting module 11 is configured to receive the first signal from the signal acquisition module 13 . The extracting module 11 is also configured to extract images of persons from the first signal.
[0030] The computing module 12 is configured to process the images of persons extracted by the extracting module 11 .
[0031] In one embodiment, the computing module 12 compares the extracted images of persons to personal information stored in the storing module 10 , to establish a mapping relationship. Thus, the computing module 12 matches the extracted images of persons to personal information stored in the storing module 10 .
[0032] FIG. 2 illustrates an embodiment of the extracting module 11 . The extracting module 11 is configured to remove a background of an image of the first signal.
[0033] The extracted images of persons can comprise a first image 1 and a second image 2 . The first image 1 is on the left-hand-side of FIG. 2 corresponding to the second image 2 .
[0034] The extracting module 11 analyzes pixels which may be comprised in the images of persons through connected component analysis-labeling. The extracting module 11 crops or cuts the images of persons from the image of the first signal.
[0035] FIG. 3 illustrates an image-cutting process that the extracting module 11 uses to cut the images of persons off from the image of the first signal.
[0036] In the embodiment, the extracting module 11 marks four endpoints of the first image 1 .
[0037] The four endpoints are configured to indicate the leftmost, the rightmost, the topmost, and the bottommost points of the first image 1 .
[0038] Similarly, the extracting module 11 marks four endpoints of the second image 2 . The four endpoints are configured to indicate the leftmost, the rightmost, the topmost, and the bottommost of the second image 2 .
[0039] The extracting module 11 cuts the first image 1 and the second image 2 off from the image of the first signal.
[0040] FIG. 4 illustrates a first process used by the computing module 12 to establish the centers of the first image 1 and of the second image 2 .
[0041] A central attachment point of the four endpoints of the first image 1 is regarded as the center of the first image 1 . Coordinates of the center of the first images are defined as (a1, b1).
[0042] A central attachment point of the four endpoints of the second image 2 is regarded as the center of the second image 2 . Coordinates of the center of the second images are defined as (a2, b2).
[0043] FIG. 5 illustrates a second process used by the computing module 12 to process the first image 1 to achieve a value of Hue and a value of Hue level of the first image 1 .
[0044] The computing module 12 processes RGB (red, green, blue) information of the first image 1 . The computing module 12 gets a HSV (hue, saturation, value) information of the first image 1 , according to a preset formula, based on RGB information of the first image 1 .
[0045] A value of hue can be used to distinguish different persons.
[0046] In the embodiment, a value of hue level can be obtained through multiplying the value of hue by four.
[0047] In a histogram of the value of hue of the first image 1 in FIG. 5 , a small difference in the value of hue can be regarded as not affecting the value of hue level. Thus, errors caused by light or lighting angles can be reduced.
[0048] The histogram of the value of hue of the first image 1 is similar to a histogram of the value of hue level of the first image 1 . Thus, the hue level of the first image 1 can be configured to distinguish between persons.
[0049] FIG. 6 illustrates a third process that the computing module 12 uses to process the second image 2 to get a value of Hue and a value of Hue level of the second image 2 .
[0050] In a histogram of the value of hue of the second image 2 in FIG. 6 , a small difference in the value of hue can be regarded as not affecting the value of hue level. Thus, errors caused by light or lighting angles can be reduced.
[0051] The histogram of the value of hue of the second image 2 is similar to a histogram of the value of hue level of the first image 1 . Thus, the hue level of the second image 2 can be configured to distinguish between persons.
[0052] FIG. 7 illustrates a process employed by the computing module 12 to compare the images.
[0053] The extracting module 11 extracts a plurality of frames of images from the first signal. The extracting module 11 provides the plurality of frames of images to the computing module 12 .
[0054] When the storing module 10 does not store information of persons to be monitored, the computing module 12 determines that the first image 1 and the second image 2 are introducing new persons to be monitored.
[0055] The computing module 12 defines the coordinates (a1, b1) of the center of the first image 1 to be a center of the coordinates of a first person A to be monitored.
[0056] The computing module 12 defines the coordinates (a2, b2) of the center of the second image 2 to be a center of the coordinates of the second person B to be monitored.
[0057] The coordinates of persons to be monitored may be changed in other frames of images. The computing module 12 monitors the coordinates of persons as indications of their presence.
[0058] In one embodiment, the extracting module 11 extracts a plurality of images from a second frame. The computing module 12 compare coordinates of images in a second frame to the coordinates (a1, b1) of the first person A in the first frame. The computing module 12 calculates a distance between the coordinates (a1, b1) of the first person A to coordinates of images from the extracting module 11 . The computing module 12 compares and finds an image which has a smallest distance to the first person A first because a person's movement between two frames must be small.
[0059] In at least one embodiment, the computing module 12 selects three images which are closest to the person to be monitored between two frames.
[0060] FIG. 8 illustrates a comparison of values of hue level of images between two frames based on the first person A. Parts which are not overlap are a different value.
[0061] The computing module 12 defines an image of a value of hue level which has a smallest difference in value to be an image of the first person A in a next frame.
[0062] In one embodiment, the computing module can get an image of the first person A in the next frame through the comparison of values of hue level only.
[0063] In one embodiment, when an image in a frame is established to be an image of a person x, the image in the frame and the image of the person x are deleted from all queues awaiting comparison.
[0064] FIG. 9 illustrates that when the computing module 12 determines that a second image 2 of a t+ 1 frame is the second person B, the computing module 12 deletes all comparisons about the second person B of the t+ 1 frame in the waiting queue.
[0065] FIG. 10 illustrates that when all persons to be monitored are established in one frame and there are still images of persons in respect of whom a mapping has not yet been established, the computing module 12 defines the images as images of new persons and stores information of them as new persons to be monitored. The computing module 12 also numbers the new persons to be monitored.
[0066] In one embodiment, when the computing module 12 adds a new person L to be monitored and the person L undergoing monitoring cannot be mapped in next or future frames, the computing module 12 deletes information of the person L.
[0067] FIG. 11 illustrates that when coordinates of a person C to be monitored is unchanging in next or future frames, the computing module 12 deletes information of the person C.
[0068] FIGS. 12-13 show an embodiment that the monitoring device 100 for counting people.
[0069] The computing module 12 set a counting line 121 in a monitoring area 1000 .
[0070] In one frame, the first image 1 and the second image 2 are in the monitoring area 1000 . Each of the first image 1 and the second image 2 has a first endpoint F and a second endpoint S. The first endpoint F is closer to the counting line 121 than to the second endpoint S. When the first endpoint F and the second endpoint S pass the counting line 121 , in that order, in future frames, the computing module 12 determines that the person has passed the counting line 121 and thus increases the count by 1.
[0071] FIG. 14 illustrates a flowchart of a monitoring method 200 . The example method is provided by way of example, as there are a variety of ways to carry out the method. The method described below can be carried out using the configurations illustrated in FIG. 1 , for example, and various elements of these figures are referenced in explaining the example method. Each block shown in FIG. 14 represents one or more processes, methods, or subroutines carried out in the example method. Furthermore, the illustrated order of blocks is by example only, and the order of the blocks can be changed. Additional blocks can be added or fewer blocks can be utilized without departing from this disclosure. The example method can begin at block 201 .
[0072] Block 201 , removing background to extract images of persons.
[0073] Block 202 , computing coordinates of centers of images of persons and value of hue level of images of persons.
[0074] Block 203 , comparing distances between coordinates of persons to be monitored and coordinates of centers of images of persons.
[0075] Block 204 , comparing value of hue level of persons to be monitored and value of hue level of images of persons.
[0076] Block 205 , adding images of persons which are not establish mapped with persons to be monitored as new persons to be monitored.
[0077] Block 206 , eliminating errors.
[0078] The monitoring method 200 can comprise: deleting an image in a frame and an image of a person from all queues of comparison when the image in the frame is established to be the image of the person.
[0079] The monitoring method 200 can comprise: deleting information of a person when the person monitor cannot be mapped with images of persons in next frames.
[0080] The monitoring method 200 can comprise: deleting information of a person when a coordinate of the person is not changed in next frames.
[0081] FIG. 15 illustrates a flowchart of a counting method 300 . The example method is provided by way of example, as there are a variety of ways to carry out the method. The method described below can be carried out using the configurations illustrated in FIG. 1 , for example, and various elements of these figures are referenced in explaining the example method. Each block shown in FIG. 15 represents one or more processes, methods, or subroutines carried out in the example method. Furthermore, the illustrated order of blocks is by example only, and the order of the blocks can be changed. Additional blocks can be added or fewer blocks can be utilized, without departing from this disclosure. The example method can begin at block 301 .
[0082] Block 301 , setting a counting line in a monitoring area.
[0083] Block 302 , monitoring movement of persons in the monitoring area.
[0084] Block 303 , determining whether both of a first endpoint and a second endpoint are across the counting line. When both of a first endpoint and a second endpoint are across the counting line, the method proceeds to block 304 . When not both of a first endpoint and a second endpoint are across the counting line, the method proceeds to block 302 .
[0085] Block 304 , increasing the count.
[0086] Block 305 , determining whether a person to be monitored has left the monitoring area. When the person has left the monitoring area, the method ends. When the person has not left the monitoring area, the method proceeds to block 302 .
[0087] While the disclosure has been described by way of example and in terms of the embodiment, it is to be understood that the disclosure is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the range of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. | A monitoring device to monitor and to count people in a certain area includes an extracting module to extract images of persons from a first signal; and a computing module to process the images of persons from the extracting module. The extracting module removes background of the first signal and extracts images of persons for the computing module. The computing module obtains coordinates of a center of each image of persons and a value of hue of each image of persons. The computing module can match images of persons to persons to be monitored and can constantly determine the instant number of persons being monitored. | 6 |
BACKGROUND OF THE INVENTION
Structurally, polymers are classified as either linear or branched wherein the term "branched" generally means that the individual molecular units of the branches are discrete from the polymer backbone, yet may have the same chemical constitution as the polymer backbone. Thus, regularly reacting side groups which are inherent in the monomeric structure and are of different chemical constitution than the polymer backbone are not considered as "branches"; that is, for example, the methyl groups pendant on a polydimethylsiloxane chain or a pendant aryl group in a polystyrene are not considered to be branches of such polymers. All descriptions of branching and backbone in the present application are consistent with this meaning.
The simplest branched polymers are the comb branched polymers wherein a linear backbone bears one or more essentially linear pendant side chains. This simple form of branching, often called comb branching, may be regular wherein the branches are distributed in non-uniform or random fashion on the polymer backbone. An example of regular comb branching is a comb branched polystyrene as described by T. Altores et al. in J. Polymer Sci., Part A, Vol. 3 4131-4151 (1965) and an example of irregular comb branching is illustrated by graft copolymers as described by Sorenson et al, Preparative Methods of Polymer Chemistry, 2nd Ed., Interscience Publishers, 213-214 (1968).
Another type of branching is exemplified by cross-linked or network polymers wherein the polymer chains are connected through the use of bifunctional compounds; e.g., polystyrene molecules bridged or crosslinked with divinylbenzene. In this type of branching, many of the individual branches are not linear in that each branch may itself contain side chains pendant from a linear chain and it is not possible to differentiate between the backbone and the branches. More importantly, in network branching, each polymer macromolecule (backbone) is cross-linked at two or more sites to other polymer macromolecules. Also the chemical constitution of the cross-linkages may vary from that of the polymer macromolecules. In this cross-linked or network branched polymer, the various branches or cross-linkages may be structurally similar (called regular cross-linked) or they may be structurally dissimilar (called irregularly cross-linked). An example of regular cross-linked polymers is a ladder-type poly(phenylsisesquinone) [sic] (poly-(phenylsilsesquioxane)). Sogah et al, in the background of U.S. Pat. No. 4,544,724, discusses some of these types of polymers and gives a short review of the many publications and disclosures regarding them. U.S. Pat. No. 4,435,548, discusses branched polyamidoamines; U.S. Pat. Nos. 4,507,466, 4,558,120, 4,568,737, 4,587,329, 4,713,975, 4,871,779, and 4,631,337 discuss the preparation and use of dense star polymers, and U.S. Pat. Nos. 4,737,550 and 4,857,599 discuss bridged and other modified dense star polymers.
Other structural configurations of macromolecular materials that have been disclosed include star/comb-branched polymers, such disclosure being found in U.S. Pat. Nos. 4,599,400 and 4,690,985, and rod-shaped dendrimer polymers are disclosed in U.S. Pat. No. 4,694,064.
Hutchins et al, in U.S. Pat. Nos. 4,847,328 and 4,851,477, deal with hybrid acrylic-condensation star polymers and Joseph et al, in U.S. Pat. Nos. 4,857,615, 4,857,618, and 4,906,691, with condensed phase polymers having regularly, or irregularly, spaced polymeric branches essentially on the order of a comb structure macromolecules.
M. Gauthier et al, Macromolecules, 24, 4548-4553 (1991) discloses uniform highly branched polymers produced by stepwise anionic grafting. M. Suzuki et al, Macromolecules, 25, 7071-2 (1992) describes palladium-catalyzed ring-opening polymerization of cyclic carbamate to produce hyperbranched dendritic polyamines. Macromolecules, 24, 1435-1438 (1991) discloses comb-burst dendrimer topology derived from dendritic grafting. U.S. Pat. No. 5,041,516 discloses other dendritic macromolecules.
The various architectures of these macromolecules results in a variety of end product uses. It is desirable to produce macromolecules that are hyperbranched (containing 2 or more generations of branching) so as to enable the production of highly functional macromolecules. Increasing the functionality of a macromolecule at a multiplicity of sites within the macromolecule can make it a much more useful molecule.
Dendrimers and hyperbranched polymers have received much attention recently due to their unusual structural features and properties. In the early 1950's, Flory, J. Am. Chem. Soc., 74, 2718 (1952) discussed the potential of AB 2 monomers, in which A and B are different reactive groups which react with each other to form a chemical bond, for the formation of highly branched polymers. However, the formation of high molecular weight hyperbranched polymers from AB 2 monomers containing one group of type A and two of type B was not accomplished until 1988 when Kim et al., Polym. Prep., 29(2), 310 (1988) and U.S. Pat. No. 4,857,630 reported the preparation of hyperbranched polyphenylene.
Numerous other hyperbranched polymers have been reported since that time by Hawker et al., J. Am. Chem. Soc., 113, 4583, (1991); Uhrich et al, Macromolecules, 25, 4583 (1994); Turner et al, Macromolecules, 27, 1611 (1994); and others. See also U.S. Pat. Nos. 5,196,502; 5,225,522; and 5,214,122. All of these hyperbranched polymers are obtained by polycondensation processes involving AB 2 monomers. In general, these hyperbranched polymers have irregularly branched structures with high degrees of branching between 0.2 and 0.8.
The degree of branching DB of an AB 2 hyperbranched polymer has been defined by the equation DB=(1-f) in which f is the mole fraction of AB 2 monomer units in which only one of the two B groups has reacted with an A group.
In contrast to hyperbranched polymers, regular dendrimers are regularly branched, macromolecules with a branch point at each repeat unit. Unlike hyperbranched polymers that are obtained via a polymerization reaction, most regular dendrimers are obtained by a series of stepwise coupling and activation steps. Examples of dendrimers include the polyamidoamide (PAMAM) Starburst™ dendrimers of Tomalia et al, Polym. J., 17, 117 (1985) or the convergent dendrimers of Hawker et al, J. Am. Chem. Soc., 112, 7638 (1990).
Recently, some highly branched polymers have been prepared in multistep processes involving a graft on graft technique that leads to a dramatic increase in molecular weight as a result of successive stepwise grafting steps. Examples of such polymers are the Combburst™ polymers of Tomalia et al., Macromolecules, 24, 1435 (1991); U.S. Pat. No. 4,694,064; and the "arborescent" polymers of Gauthier et al., Macromolecules, 24, 4548 (1991) and Macromolecular Symposia, 77, 43 (1994).
The preparation of hyperbranched polymers by a chain growth vinyl polymerization has not been accomplished previously.
DISCLOSURE OF THE INVENTION
Accordingly, the present invention is directed to a process for preparing highly branched or "hyperbranched" polymers by a chain-growth polymerization process using AB monomers. An AB monomer is one that contains two reactive groups A and B, which react independently of each other within a molecule; reaction onto A is not required to trigger the reaction of B. The A group is preferably a polymerizable vinyl group that is able to react with an active moiety such as an anion, a cation, or a conventional initiating or propagating moiety of the type well known in the art of vinyl polymerization such as those described in Principles of Polymerization, 3rd Ed., by G. Odian (Wiley) or in Polymer Synthesis 2nd Edition by P. Rempp and E. Merrill (Huthig & Wepf) to produce a new activated group A* that is capable of further reaction with any A-containing moiety present in the polymerization mixture to give an A'-A* unit in which A' is an inactive group derived from A that acts as a building block of the final polymer.
The B group is preferably a reactive group that can be activated by an activator such as one or more external activator molecules like (i) alkyl aluminum halides, e.g. EtAlCl 2 and Et 1 .5 AlC 1 .5, (ii) SnCl 4 , (iii) SnCl 4 combined with Bu 4 NCl, (iv) HI combined with I 2 , or (v) CH 3 SO 3 H combined with Bu 4 NCl and SnCl 4 or SnCl 4 combined with 2,6-di-tert-butylpyridine. Other external activators include Lewis acids, bases such as hydroxides, butyl lithium, amines and carbanions, heat, light, or radiation, which activate to produce an anion, cation, or conventional initiating or propagating moiety well known in the art of vinyl polymerization such as those described by Aoshima et al, J. Polymer Science, A, Polymer Chemistry, 32, 1729 (1994) or in Ishihama et. al. Polymer Bulletin 24 201 (1990) or in Higashimura et. al. Macromolecules 26, 744 (1993). Once activated, B becomes B*. Any B* group present in the polymerization mixture may react with any A-containing moiety present in the polymerization mixture to afford a B'-A* unit in which B' is an inactive group derived from B that acts as a building block of the final polymer.
This invention represents a new concept whereby hyperbranched polymers are obtained not from an AB 2 type monomer as described in the prior art, but from an AB monomer. The process comprises "self-constructing" polymers that contain throughout their growth a single polymerizable group A and a multiplicity of propagating species such as A* or B*, for example, a carbenium ion. In effect, an AB monomer becomes an AB* x -type macromonomer in which x increases as the polymerization proceeds.
In the process of the present invention, the "monomer" consists of polymerizable initiator molecules (AB molecules) that are activated by an external event to produce activated polymerizable initiator molecules (AB* molecules). Not all AB molecules need to be activated to A-B* since both A* and B* can add to any available A group, and any B group that remains inactivated may become activated later as a result of an exchange process. These molecules grow by adding to any available polymerizable A group present in the reaction mixture in a process that involves successive and repeated couplings of growing polymer chains with A-containing moieties, including the growing chains themselves, until the concentration of A groups is so reduced that the chain polymerization process no longer proceeds at an appreciable rate.
According to one embodiment of the present invention, an A--A monomer is added during the polymerization, commonly in the later stages of polymerization, prior to its completion or quenching, to couple pre-formed molecules of hyperbranched polymer to increase the molecular weight of the final hyperbranched polymer. An A--A monomer is added in an amount and at a time such that precipitation of the polymer does not occur. Too much A--A may lead to undesirable crosslinking. If used, a suitable amount of A--A monomer is about 0.1 to 10 mole % of total monomer. As the amount of A--A increases, the reaction generally requires greater monitoring to terminate it prior to crosslinking or insolubilization. Suitable A--A monomers may be selected from any of divinyl ether, 1,1'-bis(2-vinyloxyethoxy)-4,4'-isopropylidene diphenol, diethyleneglycol divinylether, butanediol divinyl ether, cylohexanedimethanol divinylether, hexanediol divinyl ether, cyclohexanediol divinyl ether, poly(THF) divinyl ether, polyethyleneglycol divinyl ether, ethylene glycol divinyl ether, triethyleneglycol divinyl ether, tetraethyleneglycol divinyl ether, divinylbenzene, bis-(4-ethenylphenyl)methane, bis-1,2-(4-ethenylphenyl)ethane, ethyleneglycol dimethacrylate, bis-1,2-(4-ethenylphenoxy)ethane, or bis-1,4-(4-ethenylphenoxy)butane. Particularly preferred A--A monomers are di-vinyl ether and bis-ethenylbenzene.
The process of the present invention has a "living-like" character, whereby side reactions such as chain transfer and elimination producing a double bond, (i.e. another A group) are substantially eliminated. If such side reactions are not substantially eliminated the polymerization would result in a crosslinked polymer, which is highly branched but not soluble. Such a polymer would be quite different from those of the present invention which retain their living-like character and solubility. The ultimate end uses of the polymers of the invention are also different from those of the highly crosslinked insoluble polymers that would result if side reactions were not substantially eliminated.
Because growing chains combine with each other, their number decreases as the polymerization proceeds. However, the total number of propagating species remains very high and essentially constant because each growing polymer chain sees the number of its propagating ends multiply as the polymerization proceeds while the total number of individual chains decreases.
The "self-constructing" polymerization will generally not provide a degree of branching of 1.0, because of thermodynamic, kinetic, and steric factors that may prevent some sites from reacting in regular fashion. Therefore, a hyperbranched polymer with a degree of branching below 1.0, generally about 0.05-0.95, preferably above about 0.2, more preferably above about 0.3, and still more preferably above about 0.5, will result in all but ideal conditions, i.e. when there are absolutely no side reactions and growth follows a regular geometric pattern not affected by any steric or similar factor. The degree of branching of an AB hyperbranched polymer is the mole fraction of monomer units at branch points or chain ends.
The hyperbranched polymers of the present invention retain their living-like character in that the final polymer still contains many active sites A* and B* that could be polymerized further by addition of more A or AB monomer to produce larger hyperbranched structures or star-like polymers with hyperbranched cores. Moreover, the active sites A* and B* may be quenched to produce many functionalized chain-ends. For cationic polymerizations, suitable quenching agents are generally nucleophiles such as methanol, amines, halides, water, the sodium salt of diethyl malonate, or substituted phenyl lithium. In the case of anionic polymerizations, suitable quenching agents are generally electrophiles such as aldehydes, ketones, substituted alkyl or benzyl halides, alcohols, or water. As a result, the hyperbranched polymers have and can be designed for numerous end uses, many of which are not possible for other polymers.
The hyperbranched polymers are useful in the formulation of adhesives, carriers for drugs or biological materials, slow release formulations, crosslinking agents, paints, rheology modifiers, additives for coatings and plastics, inks, lubricants, foams, components of cosmetic formulations, hairspray, deodorents and the like, components of separation media, porosity control agents, complexing and chelating agents, carriers for chiral resolution agents, components of medical imaging systems, carriers for gene transfection, and resist or imaging materials.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An example of the process of the present invention whereby a hyperbranched polymer is prepared from AB monomer 1 is described in Reaction Scheme 1: ##STR1## wherein R is ##STR2##
The A group of monomer 1 is a vinyloxy group that is known to polymerize under cationic conditions. The B group is an α-acetoxy alkyl ether that may be activated by addition of a Lewis acid such as ethyl aluminum sesquichloride (C 2 H 5 ) 1 .5 AlCl 1 .5 to afford AB* "living" moieties that can initiate their own self-polymerization.
As is well known in the art, the living-like polymerization of vinyl ethers requires that special conditions be maintained to ensure that undesirable side-reactions such as crosslinking, chain transfer or termination are avoided. The use of standard precautions, such as those described for example in the review by Sawamoto, Prog. Polym. Sci., 16, 111-172 (1991), are preferred. For example, polymerization is generally carried out in the absence of water and in the presence of agents such as ethers or heterocyclic compounds that help stabilize the "living-like" chain ends (propagating groups). Conditions must also be maintained to prevent elimination reactions. Suitable conditions are well known in the art and include the absence of water, selection and strength of a Lewis acid and the complex formed between the Lewis acid and the carbocationic center, the addition of a "basic" or "nucleophilic" additive such as tetrahydrofuran, dioxane, ethyl acetate, or tetrabutyl ammonium chloride, to stabilize the carbocationic propagating center, and the like. For an anionic process, suitable conditions include the use of a dry solvent such as tetrahydrofuran or cyclohexane and the absence of water or electrophilic impurities such as alcohols, aldehydes, ketones, bencylic or aliphatic halides. The use of additives such as glymes or cyclic ethers including tetrahydrofuran or dioxane, or tetramethyl ethylenediamine (TMEDA), or hexamethyl phosphoramide (HMPA) or crown ethers and cryptants (molecule-like crown ethers that can complex ionic species) that help stabilize the prepagating center is also well known in the art. (See, for example, P. Rempp and E. Merrill in "Polymer Synthesis" 2nd Edition, chapter 5, (Huthig & Wepf).
To simplify the representation in Reaction Scheme 1, it is assumed that all AB molecules are transformed into AB* molecules at the start of the process. This is not a requirement because both A* and B* can react with any molecule containing a reactive A group.
Once the polymerization is complete, the activated A* and B* sites can be terminated by addition of a suitable reagent. In the case of a cationic polymerization as shown in Reaction Scheme 1, this reagent could be a nucleophile like methanol, water, halide ion, amine, or the sodium salt of diethyl malonate, or a substituted phenyl lithium. In the case of an anionic polymerization, the reagent could be an electrophile such as an aldehyde, ketone, substituted alkyl or benzyl halide, alcohol, or water.
In Reaction Scheme 1, the active chain-ends or propagating sites (A* and B* groups) are shown by a "+" sign indicating their cationic nature. The counterions represented by the letter "X" and a "-" sign may be any suitable counterion such as Et 1 .5 AlCl 1 .5 (OAc), C 2 H 5 AlCl 2 OAc, and I 3 - .
Reaction Scheme 2 shows a cascade of branches resulting from the cationic polymerization of monomer 1. ##STR3##
This representation is used to convey the hyperbranched nature of the polymer and it also illustrates the involvement of both A* and B* groups in growth of the hyperbranched polymer.
Reaction Scheme 3 shows the structure of the polymer of Reaction Scheme 2 after termination by the addition of methanol as described in greater detail in the Examples. Other reagents may also be used to effect termination. ##STR4## In this fashion, a hyperbranched polymer containing numerous reactive groups at its chain ends is obtained.
AB molecules useful in the present invention are best represented by the formula A--(S) p --B in which A and B are as defined above, S is a spacer group separating A from B, and p is an integer of 0, 1, or 2. In the specific compositions shown below a bond is shown on A and B to show the point of attachment of either to the other or to S. The term AB monomer as used herein means A--(S) p --B In this formula, if p is 2, there may two of the same S groups or two different S groups. When p is 0, S is not present. A spacer group S changes the distance between branch points and may contribute to the final polymer properties such as resistance to oil, elongation, shape, rigidity, or the like, or it may be used to introduce reactive pendant groups, e.g. acrylic groups, masked amines, masked alcohols or protected carboxylic groups. Any such pendant group must be inert to the polymerization reaction used to prepare the hyperbranched polymer. While any A, B, and S groups may be used, they must be compatible with each other. The compatibility of A, B, and S groups is related to the reactivity of A, B, S, A* and B*. Compatible groups are those for which the reactivity of both A* and B* with an A group will be substantially similar such that the polymerization may proceed through either A* or B*. The compatibility of the S group with A and B relate to its inability to react chemically with A, B, A* or B* moities for example to cause the formation of a new active propagating center through processes such as addition, chain transfer, or elimination reaction. Since certain A, B, and S groups may not be compatible with each other, preferred such groups are specified below by compatible groups.
The first AB monomer grouping is represented by the formula A 1 (S 1 ) p B 1 , wherein A 1 is selected from any of ##STR5## R 1 is H or C 1 -C 4 alkyl, preferably H. R 2 is H or C 1 -C 4 alkyl, preferably H.
A suitable companion B 1 group for A 1 groups may be represented by the general formula: ##STR6## R 3 is selected from any of C 1 -C 4 alkyl, di-phenyl, aryl such as phenyl or naphthyl, optionally substituted with one or more substituent such as halo, cyano, C 1 -C 4 alkyl, and C 1 -C 4 alkoxy. Preferably, R 3 is C 1 -C 4 alkyl, most preferably methyl. R 4 is selected from any of H or C 1 -C 4 alkyl. More preferably R 4 is H. X 1 is O. "t" is 0 or 1. X 2 is OR 5 , OCOR 5 , or halo, preferably chloro. R 5 is C 1 -C 4 alkyl, haloalkyl, aryl, or aralkyl, more preferably methyl.
A suitable S 1 group which may be used with the above described companion A 1 and B 1 groups may be selected from any of C 2 -C 12 alkylene, substituted C 2 -C 12 alkylene wherein the substituents are selected from any of C 1 -C 4 alkyl or aralkyl wherein the alkyl is C 1 -C 4 ; ##STR7## wherein m and n are the same or different and are each integers from 0 to about 18, Ar 1 and Ar 2 are the same or different and are aryl selected from phenyl, naphthyl, biphenyl, optionally substituted with one or more substituents selected from C 1 -C 4 alkyl, C 1 -C 4 alkoxy, halo, or acetoxy; ##STR8## wherein y=0 or 1, and X 3 is selected from any of O, S, SO 2 , CH 2 or CO; ##STR9## wherein R 5 is C 1 -C 4 alkyl or aryl; ##STR10## polystyrene, polyisobutylene, polyester, polyether, polyolefin, polyetherketone, polycarbonate, polysulfone; or ##STR11## wherein W is ##STR12##
More preferably, S 1 is selected from any of ##STR13##
Alternatively, the A, B and S groups in an AB monomer may be represented by the formula A 2 (S 1 )B 2 wherein A 2 is selected from ##STR14## wherein R 6 is H or C 1 -C 4 alkyl, preferably H; Ar 3 is aryl or N-alkyl-3-carbazoyl wherein the alkyl is C 1 -C 8 , preferably phenyl; (X 4 ) y is O or CH 2 , preferably, X 4 is O attached to a phenyl Ar 3 at the para position; and y is 0 or 1; B 2 is selected from ##STR15## wherein R 7 is selected from any of H, CH 3 , C 1 -C 8 alkyl or aryl, preferably H; R 8 is H or C 1 -C 8 alkyl, preferably methyl; X 5 is halo, O--R 9 , or OCH 3 OCO--R 9 wherein R 9 is selected from any of C 1 -C 8 alkyl, C 1 -C 8 haloalkyl or aryl, preferably X 5 is chloro.
B 2 may also be: ##STR16## wherein R 10 is selected from any of C 1 -C 8 alkyl or aryl, preferably methyl; X 6 is halo, preferably chloro.
Alternatively, the A, B and S groups in an AB monomer may be represented by the formula A 3 (S 2 )B 3 wherein: A 3 is selected from any of ##STR17## B 3 is selected from any of ##STR18## wherein S 2 is C 1 -C 8 alkyl, aryl, aralkyl substituted aralkyl or --(CH 2 --CH 2 --O--) r , wherein r is 1-12.
Alternatively, the AB monomer is a halo-alkylsubstituted styrene of the formulas: ##STR19## wherein X 6 is chlorine or bromine and R 11 is H or C 1 -C 6 alkyl. Preferably R 11 is H or CH 3 .
Currently preferred AB monomers may be selected from any of 1-(2-vinyloxyethyloxy)-1'-[2-(1-acetoxyethoxy)-ethyloxy]-4,4'-iso propylidene diphenol; 1-vinyloxymethyl-4-(1-acetoxy)ethyloxymethylcyclohexane; 1-(2-vinyloxyethyl)-4-[1-acetoxyethyloxy)ethyl]terephthalate; 2-(2-vinyloxyethyl)-2-[(1-acetoxyethyloxy)ethyl]diethyl malonate; 1-(2-vinyloxyethyl)-3-[(1-acetoxyethyloxy)ethyl]-5-(2-methacryloyoxyethyl)-1,3,5-benzenetricarboxylate; 1-[(4-ethenyl)phenoxymethyl]-4-[4-(1-chloroethyl)phenoxymethyl]benzene; 4-(2-(1-chloroethyloxy))ethyloxystyrene; 4-(1-bromoethyl)styrene; and 4-(1-chloroethyl)styrene and chloromethylstyrene.
As used herein, unless otherwise noted alkyl and alkoxy whether used alone or as part of a substituent group, include straight and branched chains. For example, alkyl radicals include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, 3-(2-methyl)butyl, 2-pentyl, 2-methylbutyl, neopentyl, n-hexyl, 2-hexyl and 2-methylpentyl. Alkoxy radicals are oxygen ethers formed from the previously described straight or branched chain alkyl groups.
The term "aryl" as used herein alone or in combination with other terms indicates aromatic hydrocarbon groups such as phenyl or naphthyl. The term "aralkyl" means an alkyl group substituted with an aryl group.
While certain currently preferred substituents are identified above, these are not intended in any manner to limit the substituents which may be present on the various AB and C compounds, provided that they do not interfere in the primary polymerization reactions.
EXAMPLES
In the Examples, the following abbreviations have the meanings recited: DMSO=Dimethyl sulfoxide; THF=Tetrahydrofuran; CEVE=2-Chloroethyl vinyl ether; TLC=Thin layer chromatography; Et=ethyl and SEC=Size-exclusion chromatography; Bu=butyl; Ac=acetyl.
EXAMPLE I
Preparation of Vinyl Ether-Type A-B Molecule (1) 1-(2-vinyloxyethyloxy)-1'-[2-(1-acetoxyethoxy)-ethyloxy]-4,4'-isopropyllidenediphenol ##STR20##
A mixture of bisphenol A (23g), powdered NaOH (12g), and DMSO (45ml) were heated at 70°-75° C. with stirring under nitrogen for 1.5 hours. To the mixture, CEVE (39g) was added slowly over 2 hours. An additional 20ml of DMSO was added to this viscous mixture. Then the solution was heated for another 5 hours at 70°-75° C., and was allowed to stand overnight at room temperature. The reaction mixture was washed with water, and the isolated crude product was purified by crystallizing twice from ethanol. The aromatic bisvinyl ether (2) was obtained as a white-pale yellow solid in 75% yield. The preparation of acetic acid-adduct of aromatic bisvinyl ether was carried out as follows. To the solution of aromatic bisvinyl ether 2 (7.4g) in toluene (15ml), was added a slight excess of glacial acetic acid (1.4g). The mixture was heated at 70° C. under nitrogen for 8 hours. After cooling the mixture was evaporated to remove toluene and unreacted acetic acid. A yellowish oil was obtained almost quantitatively (>95%). TLC showed that the crude products contained three major materials: unreacted 2, mono-adduct of acetic acid to 2 vinyl ether 1, and di-adduct of acetic acid. The mono-adduct of acetic acid to 2 (1), an A-B type molecule, was separated from the mixture by flash chromatography eluting with hexane/diethyl ether (60/40); the Rf values of three fractions are 0.56, 0.31, 0.14, respectively. The eluent was then removed on a rotary evaporator and vacuum dried for 1 hour. A colorless transparent oil was obtained (43% yield based on 2).
Cationic Polymerization of 1 as an A-B Trade Molecule
Purified 1 was dissolved in dry THF and the solution was allowed to stand overnight over granular CaH 2 , to remove trace amounts of water. The transparent supernatant fraction was then transferred to the reaction vessel and used to prepare the monomer solution. Polymerization was carried out under dry nitrogen in a baked glass vessel equipped with a three-way stopcock. The reaction was initiated by addition of Et 1 .5 AlCl 1 .5 in toluene used as an activator to the monomer solution in THF at 0° C. ([Et 1 .5 AlCl 1 .5 ]0=[1] 0 =0.15mol/l, total scale of the reaction: 5ml). THF was used as a solvent to stabilize the propagating carbocations by its nucleophilic interaction and prevent the occurrence of various side reactions such as crosslinking, chain transfer reaction etc. After 24 hours, the reaction was quenched by 2ml of 0.3wt % ammonia in methanol. The quenched reaction mixture was diluted with ethyl acetate and then washed with dilute hydrochloric acid (0.6mol/l) and water to remove the initiator residues. After neutralization, the polymer product was recovered by evaporation of the solvents under reduced pressure, and vacuum dried overnight. The colorless polymer is isolated quantitatively as a thicks liquid. The polymer is completely soluble in THF, ethyl acetate, and chloroform. The weight average molecular weight measured by SEC with polystyrene standard (THF, 40° C.) was MW=10 4 . The molecular weight distribution curve showed a significant shoulder extending to 10 5 . The structure of the polymer was confirmed by NMR and IR.
EXAMPLE II
Preparation of Hyperbranched Poly(1) with Higher Molecular Weight
The polymerization of 1 was carried out as above with addition of a small amount of 2 (A--A type molecule, 0.01 mol/l) after 24 hours followed by quenching. The work up process was similar to that of Example I. The polymer was obtained in 90% yield. The polymer is completely soluble in THF, ethyl acetate, chloroform. The SEC of the polymer shows a value of MW=3×10 5 .
EXAMPLE III
Preparation of Vinyl Ether-Type A-B Molecule (3) 1-vinyloxymethyl-4-(1-acetoxy)ethyloxymethyclohexane ##STR21##
Vinyl ether-type A-B molecule 3 was prepared by the following two steps that include the synthesis of bisvinyl ether 4 by vinyl transetherification and the reaction with acetic acid. To a solution of distilled ethyl vinyl ether (29ml, 0.3mol), 1,4-cyclohexyldimethanol (11g, 0.075mol), and 1,4-dioxane (15ml) were added mercury(II) acetate (0.75g, 0.0024mol) as a catalyst and molecular sieves 4A (20g) as an adsorbent of ethanol. The reaction was carried out at room temperature for 5 hours with occasional shaking. The reaction was then stopped by adding 2g of anhydrous potassium carbonate. The reaction mixture was washed with water, dried over Na 2 SO 4 , and fractionated by flash chromatography eluting with hexane/diethyl ether (50/50) (yield ˜20%).
The reaction of 4 (5.2g) with acetic acid (1.9g) was carried out at 70° C. under nitrogen. After 4 hours, the reaction mixture was allowed to cool, and evaporated to remove unreacted acetic acid. A colorless oil was obtained. The mono-adduct of acetic acid to 4, an A-B type molecule (3), was separated from the mixture by flash chromatography eluting with hexane/diethyl ether (80/20). The eluent was removed on a rotary evaporator and vacuum dried for 1 hour. The product was obtained as a colorless transparent oil (40% yield based on 4).
Cationic Polymerization of 3 as an A-B Type Molecule
Purified 3 was dissolved in dry ethyl acetate and the solution was allowed to stand overnight over granular CaH 2 to remove trace amounts of water. The transparent supernatant fraction was transferred to the reaction vessel and used to prepare the monomer solution. The polymerization process was similar to that of compound 1 (see Example I) except for the use of EtAlCl 2 as the activator instead of Et 1 .5 AlCl 1 .5. The reaction was initiated by addition of EtAlCl 2 in hexanes to a monomer solution in ethyl acetate at 0° C. ([EtAlCl 2 ] 0 =[3] 0 =0.15mol/l, total scale of the reaction: 5ml). Ethyl acetate was used as a solvent to stabilize the propagating carbocations by its nucleophilic interaction and prevent the occurrence of various side reactions such as crosslinking, chain transfer reaction etc. The polymerization reaction progressed homogeneously. After 2 hours, the reaction was quenched by 2ml of 0.3 wt % ammonia in methanol. Work up was as described for compound 1 (see Example I). The polymer was obtained in 97% yield as a viscous liquid. The polymer was completely soluble in THF, ethyl acetate, chloroform. The weight average molecular weight measured by SEC with polystyrene standard (THF, 40° C.) was MW=15,000. The molecular weight distribution curve showed a shoulder extending above 10 5 . The structure of the polymers was confirmed by NMR and IR.
EXAMPLE IV
Preparation of Vinyl Ether-Type A-B Molecule (5) 1-(2-vinyloxyethyl)-4-[1-acetoxyethyloxy)ethyl]terephthalate
A solution of terephthaloyl chloride (10g, 0.05mol) in diethyl ether (60ml) was added slowly to the solution of 2-hydroxyethyl vinyl ether (11g, 0.12mol) in pyridine (17g) at 0° C. with stirring under nitrogen. The reaction mixture was allowed to react for another 15 min at 0° C., and then left overnight at room temperature ##STR22## with stirring under nitrogen. The solution was poured into water (300 ml) with stirring, and the product was extracted with diethyl ether. The organic layer was washed with water, and dried over MgSO 4 . The product was recovered by evaporation of the solvent under reduced pressure, to yield a white solid (15g, 96% based on terephthaloyl chloride). The compound was purified by flash chromatography eluting with CH 2 Cl 2 to give 12g of compound 6. The preparation of the acetic acid-adduct was carried out as previously described for compound 1 (see Example I). To the solution of 6 (5g) in toluene (14ml), was added a slight excess of glacial acetic acid (1.2g), and the mixture was heated at 70° C. under nitrogen for 10 hours. The reaction mixture was then allowed to cool and evaporated to remove toluene and unreacted acetic acid. The colorless oil was obtained almost quantitatively (>95%).
The mono-adduct of acetic acid to 6, an A-B type molecule 5, was separated from the mixture by flash chromatography eluting with hexane/diethyl ether (50/50). The eluent was then removed on a rotary evaporator and vacuum dried for 1 hour. A white solid was obtained (41% yield based on terephthaloyl chloride).
Cationic Polymerization of 5 as an A-B Type Molecule
Purified 5 was dissolved in dry THF and allowed to stand overnight over granular CaH 2 to remove trace amounts of water. The polymerization and following work up processes were similar to those for compound 3 (Example III). The polymer was obtained in 95% yield. The polymer was completely soluble in THF, ethyl acetate, chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE V
Preparation of Vinyl Ether-Type A-B Molecule (7) 2-(2-vinyloxyethyl)-2-[(1-acetoxyethyloxy)ethyl]diethyl malonate ##STR23##
To a solution of sodium ethoxide (8.7g) in absolute ethanol (71ml) was added at room temperature, ethyl malonate (19g) and CEVE (24ml) in this order. The solution was heated at reflux with stirring under nitrogen for 5 hours. After most of the ethanol was evaporated under reduced pressure, the reaction mixture was diluted with diethyl ether, and the sodium chloride was filtered off. The organic layer was washed with 10% aqueous NaCl, then dried over MgSO 4 , and evaporated under reduced pressure to give a liquid product in almost quantitative yield.
Compound 9 was prepared by the reaction of CEVE (10g) and a slight excess of glacial acetic acid (7g) at 40° C. under nitrogen overnight, to give a slightly yellowish liquid almost quantitatively. Quantitative addition of acetic acid was also confirmed by 1H NMR. The solution of sodium salt of 8 was prepared by treating distilled 8 with sodium hydride in THF at 40° C. under nitrogen for 1 hour. The reaction with excess distilled compound 9 was carried out at 40° C. under nitrogen for 24 hours. The resulting reaction mixture was washed with water, dried with MgSO 4 , and then evaporated. The crude product was purified by chromatography, to give compound 7 in 48% yield.
Cationic Polymerization of 7 as an A-B Type Molecule
Purified 7 was dissolved in dry THF and the solution was allowed to stand overnight over granular CaH 2 just before use as a monomer solution, to remove trace amounts of water. The polymerization and the following work up process were similar to those for compound 3 (see Example III). The polymer was obtained in a 95% yield. The polymer was completely soluble in THF, ethyl acetate, and chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE VI
Preparation of Vinyl Ether-Type with a Functional group (10) 1-(2-vinyloxyethyl)-3-[(1-acetoxyethyloxy)ethyl]-5-(2-methacryloyloxyethyl)-1,3,5-benzene tricarboxylate ##STR24##
A solution of 1,3,5-benzenetricarbonyl trichloride (1.8g), purified by recrystallization from hexanes, in CH 2 Cl 2 (20ml) was slowly added to the solution of 2-hydroxyethyl vinyl ether (1.2g) and 2-hydroxyethyl methacrylate (0.8g) in pyridine (60ml) at 0° C. with stirring under nitrogen, and the mixture was allowed to stir overnight at room temperature. The solution was diluted with CH 2 Cl 2 , washed with water, and dried over MgSO4, and the solvent was removed under reduced pressure. The compound having two vinyloxy groups and one methacrylate group 11 was separated by flash chromatography eluting with hexane/diethyl ether to give compound 11 (35% based on 1,3,5-benzenetricarbonyl trichloride).
The preparation of the acetic acid-adduct was carried out in a manner similar to that for compound 1 (see Example I). To the solution of 11 (3.2g) in toluene (14ml), was added a slight excess of glacial acetic acid (0.6g), and the mixture was heated at 70° C. under nitrogen for 10 hours. The reaction mixture was then allowed to cool and evaporated to remove toluene and unreacted acetic acid. The colorless oil was obtained almost quantitatively (>95%).
The mono-adduct of acetic acid to 11, an AB-type molecule having a pendant functional group (10), was separated from the mixture by chromatography. The eluent was then removed on a rotary evaporator and vacuum dried for 1 hour. A white solid was obtained (41% based on 11).
Cationic Polymerization of 10 as an A-B Type Molecule
Purified 10 was dissolved in dry THF and the solution was allowed to stand overnight over granular CaH 2 to remove trace amounts of water. The polymerization and the following work up process were similar to that for compound 3 (see Example III). The polymer was obtained in 95% yield. The polymer was completely soluble in THF, ethyl acetate, and chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE VII
Preparation of Styrene-Type A-B Molecule (12) 1-[(4-ethenyl)phenoxymethyl]-4-[4-(1-chloroethyl)phenoxymethyl]benzene ##STR25##
A mixture of freshly prepared p-hydroxystyrene (12g), α,α'-dibromo-p-xylene (13.2g), dried potassium carbonate (17.3g), and 18-crown-6 (2.6g) in dry acetone (100ml) was heated to reflux and stirred vigorously under nitrogen for 20 hours. The reaction mixture was allowed to cool and evaporated to dryness. The residue was partitioned between CH 2 Cl 2 and water, and the aqueous layer was further extracted with CH 2 Cl 2 . The combined organic layers were then dried and evaporated to dryness. After purification by chromatography a 26% yield of compound 13 was isolated.
The HCl-adduct was prepared by bubbling dry HCl gas through a solution of 13 in toluene at 0° C. The formation of mono-adduct of HCl 12 was followed by TLC, which showed that the crude product contained four materials. Any remaining HCl in the solution was removed by bubbling dry nitrogen gas. The mono-adduct of HCl to 13 (12), an A-B type molecule, was separated from the mixture by chromatography. After evaporation of the solvent under reduced pressure and vacuum drying, 12 was obtained in 31% yield.
Cationic Polymerization of 12 as an A-B Type Molecule
Purified 12 was dissolved in dry toluene. The polymerization process was similar to that of compound 1 (Example I), except for the use of different activator. Polymerization was carried out under dry nitrogen in a baked glass vessel equipped with a three-way stopcock. The reaction was initiated by mixing the of ZnCl 2 in diethyl ether to the monomer solution in toluene at 0° C. ([12] 0 =0.15 mol/l, [ZnCl 2 ] 0 =0.03mol/l, total scale of the reaction: 5ml). The work up process was also similar to that of compound 1 (Example I). The polymer was obtained in 85% yield. The polymer was completely soluble in THF, ethyl acetate, and chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE VIII
Preparation of Styrene-Type A-B Molecule (14) 4-(2-(1-chloroethyloxy))ethyloxystyrene ##STR26##
A mixture of p-hydroxystryrene (12g), powdered NaOH (6g), and DMSO (40ml) was heated at 70°-75° C. with stirring under nitrogen for 1.5 hours. To the mixture, CEVE (20g) was added slowly over 2 hours. Then the solution was heated for another 5 hours at 70°-75° C., and was allowed to stand overnight at room temperature. The reaction mixture was washed with water, and the isolated crude products were purified by crystallization. Compound 15 was obtained in 70% yield. The HCl-adduct to 15 was prepared by bubbling dry HCl gas through a solution of 15 in toluene at 0° C. The formation of mono-adduct of HCl (14) was followed by TLC. Any remaining HCl in the solution was removed by bubbling dry nitrogen gas. The mono-adduct of HCl to 15, an A-B type molecule, was separated from the mixture by chromatography. After evaporation of the solvent under reduced pressure and vacuum drying, 14 was obtained in 46% yield.
Cationic Polymerization of 14 as an A-B Type Molecule
Purified 14 was dissolved in dry toluene. The polymerization process was same as that of compound 12 (Example VII). The reaction was initiated by mixing the ZnCl 2 in diethyl ether used as an activator and the monomer solution in toluene at 0° C. ([14] 0 =0.15 mol/l, [ZnCl 2 ] 0 =0.06mol/l, total scale of the reaction: 5ml). The work up process was also the same as that for compound 12 (see Example VII). A viscous polymer was obtained in 80% yield. The polymer was completely soluble in THF, ethyl acetate, chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE IX
Copolymerization of Two Different A-B Type Molecules
The copolymerization of two different A-B type molecules of comparable reactivities was carried out similarly to Examples I and III. Purified 1 and 3 were dissolved in dry THF and the solution was allowed to stand overnight over granular CaH 2 to remove trace amounts of water. The transparent supernatant fraction was transferred to the reaction vessel and used as the monomer solution. The polymerization process was similar to those for compound 3 (see Example III). The reaction was initiated by addition of EtAlCl 2 in hexanes to a monomer solution in THF at 0° C. ([EtAlCl 2 ] 0 =[1] 0 +[3] 0 =0.15mol/l, total scale of the reaction: 5ml). THF was used as a solvent to stabilize the propagating carbocations by its nucleophilic interaction and prevent the occurrence of various side reactions such as crosslinking, chain transfer reaction etc. After 10 hours, the reaction was quenched by 2ml of 0.3 wt % ammonia in methanol. Work up was as described for compound 1 (see Example I). The polymer was obtained in 97% yield as a viscous liquid. The polymer was completely soluble in THF, ethyl acetate, chloroform. The polymer was characterized as described in Examples I and III.
EXAMPLE X
Polymerization of 4-(1-chloroethyl) styrene.
A freshly dried glass apparatus was used for this polymerization under nitrogen atmosphere. A solution of 4-(1-chloroethyl) styrene (0.55g, 3.3 mmoles) in dichloromethane (4.5ml) was cooled to 0° C. then pre-cooled SnCl 4 (0.5ml of 1M solution in dichloromethane) was added under nitrogen. A color change was observed upon mixing and after 8 hours the polymerization was quenched by addition of pre-chilled methanol (2ml) containing a trace of ammonia. The color was discharged and the mixture diluted with dichloromethane (30ml) then washed with 2% aqueous HCl, (40ml) and distilled water (5 times, 40 ml each). The organic layer was concentrated and the polymer (80% yield) isolated by precipitation. The polymer was soluble in THF. After reprecipitation into hexane its molecular weight measured by standard GPC with polystyrene standards was approximately 90,000 daltons while the molecular weight obtained by universal calibration using in-line viscometry was 300,000 daltons, confirming the hyperbranched character of the product. The structure of the polymer was further confirmed by NMR in CDCl 3 and by infrared analysis.
EXAMPLE XI
Polymerization of 4-(1-chloroethyl) styrene.
The polymerization of the same monomer was also accomplished as described above using inverse addition of the pre-chilled monomer solution (4 mmoles) in dichloromethane (5ml) to a solution containing SnCl 4 (2 mmoles) and tetrabutylammonium chloride (1 mmole) in dichloromethane cooled to -30° C. Once the addition was complete the mixture was brought slowly from -30° C. to 0° C. with occasional mixing until the polymerization was quenched after 12 hours as described above. The polymer was processed and characterized as described above in Example X. | A process for preparing hyperbranched polymers from AB monomers using a self constructing approach is disclosed. Hyperbranched polymers of a living-like character produced by such process are also disclosed. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the priority of German Patent Application, Serial No. 10 2010 012 831.7-56, filed Mar. 25, 2010, pursuant to 35 U.S.C. 119(a)-(d), the content of which is incorporated herein by reference in its entirety as if fully set forth herein.
[0002] This is one of five applications all filed on the same day. These applications deal with related inventions. They are commonly owned and have the same inventive entity. These applications are unique, but incorporate the others by reference. Accordingly, the following U.S. patent applications are hereby expressly incorporated by reference: “CROSS MEMBER”, representative's docket no.: PELLMANN-2; “SIDE RAIL”, representative's docket no.: PELLMANN-3; “AUTOMOBILE COLUMN”, representative's docket no.: PELLMANN-5; and “METHOD FOR PRODUCING A MOTOR VEHICLE COMPONENT, AND A BODY COMPONENT”, representative's docket no.: PELLMANN-6.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to a transmission tunnel, and more particularly to a transmission tunnel for installation in a motor vehicle body. The invention also relates to a floor group of a motor vehicle, which includes a transmission tunnel.
[0004] It would be desirable and advantageous to provide an improved transmission tunnel which obviates prior art shortcomings and can be produced at low cost in industrial-scale production while still being reliable in operation.
SUMMARY OF THE INVENTION
[0005] According to one aspect of the invention, a transmission tunnel is made of a sheet steel blank and has a first region which underwent heat treatment, a second region which is not heat-treated, and a transition zone between the first and second regions. The transition zone is defined by a width which is smaller than or equal to 50 mm.
[0006] According to another aspect of the invention, a floor group of a motor vehicle includes a transmission tunnel and at least one component coupled with the transmission tunnel.
[0007] According to another advantageous feature of the present invention, the transmission tunnel can be produced by hot-forming and press-hardening of a steel sheet blank, with the first region undergoing heat treatment after press-hardening.
[0008] In accordance with the present invention, the material property in certain regions of the transmission tunnel of the invention can be produced with a reliable process and with desired properties. After hot-forming and press-hardening of a steel sheet blank made from high-strength hardenable steel, a particular area of the transmission tunnel is targeted to undergo a heat treatment. Heat-treating a particular area of the transmission tunnel, will hereinafter also be referred to a “partially” heat-treating or “partial” heat treatment. The heat treatment is carried out below the austenitic transition temperature, so that ductile material structures are produced in the heat-treated regions of the transmission tunnel.
[0009] A transmission tunnel according to the invention is integrated in a motor vehicle body centrally in the floor group of the motor vehicle body. The transmission tunnel is integrated through coupling to other components of the floor group, for example floor panels, side rails, cross beams, rocker panels and/or engine supports. As a result, a transmission tunnel is of particular and central importance in the event of a crash. The transmission tunnel is able to safely counter a deformation of the floor group in the event of a crash. Moreover, an intentional deformation can be facilitated by targeted heat treatment in certain regions, without causing the formation of cracks or tearing. The crash energy can then be particularly advantageously converted into deformation energy in these regions of intentional deformation. In addition, coupled add-on components are secured on the transmission tunnel, thereby guaranteeing a strong passenger compartment.
[0010] With the transmission tunnel according to the invention, the energy absorption capacity of the entire motor vehicle body is increased while maintaining high stiffness. In a motor vehicle equipped with the transmission tunnel according to the invention, considerable energy is absorbed by converting kinetic energy from the impact into deformation energy while retaining a high stiffness of the passenger compartment.
[0011] According to one advantageous embodiment of the transmission tunnel of the invention, due to the regions that remain intentionally unchanged after press-hardening, components of the drive train, of the transmission bell housing and/or of the motor may be prevented from penetrating the motor vehicle body. The high hardness in certain regions attainable in this manner therefore may prevent an undesirable deformation in these regions.
[0012] In yet another advantageous feature of the present invention, the width of the transition zone may be less than 30 mm, in particular less than 20 mm. Within the context of the present invention, the transition zone from a heat-treated region to a non-heat-treated region is comparable to a zone affected by heat from a weld seam. Moreover, the material structure is changed in the transition zone which is not necessarily desirable.
[0013] According to another advantageous feature of the present invention, a transition zone of less than 15 mm may advantageously be realized on the transmission tunnel. Accordingly, those regions on the individual components, in particular on the transmission tunnel, which are designed to deform in the event of a crash and those regions which can essentially retain their shape in the event of a crash, can already be designated in the manufacture of a crash-optimized motor vehicle body.
[0014] In yet another advantageous embodiment, the width of the heat-treated region may correspond to 0.2-times to 3.0-times the width and/or the height of the heat-treated region. In relation to the distribution of the total stress inside the component, a particularly advantageous embodiment for the crash and stiffness structure of the motor vehicle body is attained.
[0015] According to another advantageous feature of the present invention, joining flanges may be partially heat-treated. The heat-treated region, in particular embodied as joining flange, is advantageous for the crash property and stiffness of the body, such as an exemplary integral body-frame body. As already described above, parts of the floor assembly, rocker panels, side rails, engine supports and various components for coupling the drive train may be arranged on the joining flanges of a transmission tunnel. The attachment may be produced by gluing, riveting, welding, brazing or similar coupling processes.
[0016] The region which has been partially heat-treated does not have a tendency to tear or detach in the event of the accident and therefore holds the surrounding and connected structural and safety-related components together. This is particular advantageous for the stability of the passenger compartment and hence the protection of occupants.
[0017] Another advantage relates to regions subjected to an intentional deformation in the event of an accident. The regions defined for intentional deformation can be deformed without tearing. This increases also the overall energy absorption capability of the entire motor vehicle body accompanied by a small penetration depth into the passenger compartment.
[0018] According to another advantageous feature of the present invention, due to the intentionally remaining hardened regions, the transmission tunnel may also a high torsional stiffness and connection stiffness and can also hence be used for transmitting large drive forces of a drive train extending, for example, through the transmission tunnel. Another advantage in conjunction with the intentional partial heat treatment is that vibrations in the drive train, for example by stick-slip-behavior of a motor vehicle, can be attenuated to a certain degree as a result of the targeted softer heat-treated regions. This improves the driving comfort due to a reduction of the vibrations of the body.
[0019] Another application is, for example, the intentional deformation of individual regions to facilitate lower cost repairs after an accident. This deformation is intended to transfer energy to be dissipated into the body, thereby once more improving the safety for the vehicle occupants in the event of a crash.
[0020] The regions heat-treated with the method of the invention may deform in the event of a crash so as to produce intentional wrinkles accompanied by intentional absorption of energy. Additionally, the heat-treated regions tend to form less cracks due to their rather ductile structure compared to the hot-formed and press-hardened, hard and brittle structure.
[0021] The partial heat treatment of joining flanges has the additional advantage that the joining flanges have ductile material properties. With a material connection produced by thermal joining, a structural change takes place in a subsequent process in the zone affected by heat generated by the joining method. A ductile section of the transmission tunnel is particularly advantageous for the welding process and the material structure created in the zone affected by heat of the welding process. This is particularly advantageous for the durability of the connected weld seams of the motor vehicle in the event of an accident.
[0022] According to another advantageous feature of the present invention, openings in the transmission tunnel may be partially heat-treated. These openings may be incorporated in the component, for example, to reduce weight or for passing through other components, for example a wiring harness or an actuator for seat adjustment and the like. Cracks can form in an accident particularly in the region of the openings and also in the end region of openings due to stress in the components, in particular surface stress, which may extend over the entire component. By reducing the surface stress, a ductile material structure is obtained in this region. This counters the formation of cracks and hence also an easier unintentional deformation of the transmission tunnel.
[0023] According to another advantageous feature of the present invention, an end region of the transmission tunnel may be partially heat-treated, wherein a joining flange arranged on the end region is not heat-treated. This has the advantage that when incorporating the transmission tunnel in a motor vehicle body, the heat-treated regions can attenuate loads caused by reverse bending stresses, which may be introduced into the body by, for example, body torsion or other driving parameters, for example drive train vibrations and the like. This has a beneficial effect particularly with respect to the durability of the motor vehicle body by reducing the surface stress in the end regions, positively affecting the required crash properties of the joining flanges connected to the motor vehicle body that are not heat-treated.
[0024] According to another advantageous feature of the present invention, spot-shaped regions of the transmission tunnel may be partially heat-treated, wherein the spot-shaped regions have dimensions of less than 50 mm, suitably less than 30 mm. For connecting the transmission tunnel to a motor vehicle body, these spot-shaped regions may be advantageously intentionally heat-treated, thereby allowing spot welding or other local laser welding within the spot-shaped regions of a type frequently performed in the production of motor vehicles. In the event of a motor vehicle crash, the transmission tunnel with the coupled components has again high connection strength in these connected spot-shaped regions. Crack formation or tearing or disconnection is significantly reduced with the heat-treated spot-shaped regions.
[0025] According to another advantageous feature of the present invention, the heat-treated regions may have a yield strength between 300 N/mm 2 and 1300 N/mm 2 , suitably 400 N/mm 2 to 800 N/mm 2 . Currently preferred is a yield strength of 400 N/mm 2 to 600 N/mm 2 . In addition, the heat-treated regions may advantageously have a tensile strength between 400 N/mm 2 and 1600 N/mm 2 , suitably 500 N/mm 2 to 1000 N/mm 2 . Currently preferred is a tensile strength of 550 N/mm 2 to 800 N/mm 2 , and advantageously a ductility between 10% and 20%, and suitably 14% to 20%. The material still has the required high-strength mechanical properties; however, due to the reduced tensile strength, elongation limit and the increased ductility the material is sufficiently ductile to produce wrinkles, instead of breaking or tearing, under a suitable load. This advantageously counters potential crack formation in the heat-treated region of the material.
[0026] According to another advantageous feature of the present invention, the yield strength and/or tensile strength may decrease in the transition zone from heat-treated region to non-heat-treated region with a gradient of more than 100 N/mm 2 per 1 cm, suitably of more than 200 N/mm 2 per 1 cm. Currently preferred is a gradient of more than 400 N/mm 2 per 1 cm. According to another advantageous feature of the present invention, very small local regions may be heat-treated, whereas the transition zones are kept smaller in relation thereto. The transition zone resulting from the gradient between the hot-formed and press-hardened, non-heat-treated region and the partially heat-treated region has a therefore a dimension of less than 50 mm, currently preferred between 1 mm and 20 mm. This produces small local heat-treated regions with sharp edges and smaller transition zones compared to the heat-treated regions.
[0027] According to another advantageous feature of the present invention, the transmission tunnel may be partially heat treated by heating the region to be heat-treated to a heat-up temperature, holding the heat-up temperature during a holding time, and cooling down from the heat-up temperature in at least two phases.
[0028] According to another advantageous feature of the present invention, the component may be heated up to and held at the heat-up temperature in a temperature range between 500° C. and 900° C. The temperature range between 500° C. and 900° C. for heat-up and holding the heat-up temperature intentionally and reliably reduces stress in the heat-treated regions during production.
[0029] According to another advantageous feature of the present invention, heat-up may occur over a time period of up to 30 seconds, suitably of up to 20 seconds, currently preferred of up to 10 seconds, in particular of up to 5 seconds. The short heat-up phase for reaching the heat-up temperature is, in combination with a subsequent holding phase, particularly advantageous for the process reliability of the produced component.
[0030] According to another advantageous feature of the present invention, the holding time may extend over a time period of up to 30 seconds. Advantageously, the holding time extends over a time period of up to 20 seconds, currently preferred of up to 10 seconds, in particular of up to 5 seconds. Within the context of the invention, the hardening and tempering process can be particularly reliably performed by intentionally controlling the material structure transformation at a constant temperature and is only affected by the duration of the holding time. The attained heat-up temperature is held substantially constant.
[0031] According to another advantageous feature of the present invention, the first cooldown phase may have a longer duration than the second cooldown phase. This is particularly advantageous for the material structure to be produced and for the related processing steps. The transmission tunnel according to the invention can be post-processed immediately following processing. It is therefore feasible within the context of the invention that the heat-treated regions as well as the transmission tunnel have a component temperature of 200° C. when transferred to a post-processing process.
[0032] Moreover, the second phase may advantageously be performed in a time period of up to 120 seconds, suitably of up to 60 seconds.
[0033] In the context of the invention, a transmission tunnel also refers to an assembled transmission tunnel. The transmission tunnel here consists of at least one hot-formed and press-hardened steel component which after press-hardening is sold-wise heat-treated at least in one region, coupled with various other components. Partial heat treatments of the other components may possibly have also been performed after press-hardening; alternatively, untreated sheet steel components may also be considered for coupling. Additionally, for example milled components or fiber composite components may be suitably within the context of the invention for coupling with a hot-formed and press-hardened transmission tunnel that is partially heat-treated after press-hardening.
[0034] If coupling with other sheet steel components is contemplated, the transmission tunnel according to the invention may also be partially heat-treated in the coupling regions of the coupling. This provides similar advantages as a non-piece transmission tunnel of the type described above.
[0035] According to another advantageous feature of the present invention, the floor group is characterized in that the coupling regions between transmission tunnel and component may be, after coupling, heat-treated at least in zones.
BRIEF DESCRIPTION OF THE DRAWING
[0036] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:
[0037] FIG. 1 shows a detail of a transmission tunnel according to the invention;
[0038] FIG. 2 shows a transmission tunnel of an unillustrated motor vehicle;
[0039] FIG. 3 shows a floor assembly according to the invention with a centrally arranged transmission tunnel;
[0040] FIG. 4 shows an assembled transmission tunnel;
[0041] FIG. 5 shows another perspective view of a transmission tunnel from below; and
[0042] FIGS. 6 a ), b ), c ) show different temperature curves during manufacture of a transmission tunnel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0043] Throughout all the figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.
[0044] Turning now to the drawing, and in particular to FIG. 1 , there is shown a detail of a transmission tunnel. As can be seen, a heat-treated region WB is according to the present invention formed in a non-heat-treated region NWB. A transition zone UB is disposed between the non-heat-treated region NWB and the heat-treated region WB. A material structure having the tendency to be ductile is created in the heat-treated region WB, whereas the material structure in the non-heat-treated region NWB is hard and brittle. The transition zone UB is inherently created during treatment of the heat-treated region WB. In the context of the present invention, the transition zone UB has essentially a width a, which extends from the heat-treated region WB to the non-heat-treated region NWB, which is particularly small in relation to the heat-treated region WB and which has substantially sharp edges.
[0045] FIG. 2 shows a transmission tunnel 1 of an unillustrated motor vehicle. The transmission tunnel 1 has and opening 2 disposed on its upper center section 3 . The marginal regions 4 of the opening 2 in the transmission tunnel 1 according to the invention are partially heat-treated, thereby reducing existing surface stress.
[0046] The transmission tunnel 1 according to the invention also has joining flanges F extending along its sides. The joining flanges F can hereby, as illustrated, adapted in a front section 6 of the transmission tunnel 1 to the geometric features for coupling with an unillustrated floor group. As illustrated, the front part 7 of the joining flange F is arranged at an angle α relative to the rear part 8 of the joining flange F. The transition segment 9 from the front to the rear part 7 , 8 is according to the invention partially heat-treated. Conversely, the front part 7 of the joining flange F is still in the material state attained after press-hardening, to prevent unillustrated engine components from entering or penetrating the passenger compartment.
[0047] FIG. 3 shows a floor arrangement 10 according to the invention with a centrally arranged transmission tunnel 1 . Floor panels 11 are coupled to corresponding sides 5 of the transmission tunnel 1 . A splash guard 12 is arranged in the front section 6 of the transmission tunnel 1 which separates the passenger compartment 13 from the unillustrated drive components. The number of recesses 14 , beads 15 and openings are arranged in the transmission tunnel 1 itself as well as in the floor panels 11 . According to the invention, these regions are also partially heat-treated, thereby providing an optimized crash response of the motor vehicle with the overall design of the floor group 10 . This simultaneously produces a high deformation stiffness of the passenger compartment, while also being able to absorb energy by converting kinetic crash energy into deformation energy.
[0048] FIG. 4 shows an assembled transmission tunnel 1 . The transmission tunnel 1 includes an upper hot-formed, press-hardened component 16 which is partially heat-treated after press-hardening, and a lower hot-formed, press-hardened component 17 which is also partially heat-treated after press-hardening. The upper component 16 and lower component 17 have each joining flanges F disposed at the respective side regions 18 . These joining flanges F are coupled with each other via a coupling process. The coupling locations 19 are according to the invention partially heat-treated after the joining process, for example a formal joining process.
[0049] FIG. 5 shows another perspective view of a transmission tunnel 1 from below. This embodiment of the transmission tunnel 1 has a number of recesses 14 , beads 15 and openings, which are partially heat-treated in their regions or in the surrounding regions. Moreover, the transmission tunnel 1 in FIG. 5 has spot-shaped heat treatment zones 20 which according to the invention are heat-treated after press-hardening end have only a narrow transition zone UB to the press-hardened regions.
[0050] FIG. 6 a shows a temperature curve as a function of time, with the time intervals heat-up time (t 1 ), holding time (t 2 ), cooldown time first phase (t 3 ) and cooldown time second phase (t 4 ). Also shown on the temperature axis are the heat-up temperature (T 1 ) and a first cooldown temperature (T 2 ).
[0051] Starting with a blank of sheet steel which is hot-formed and press-hardened to produce a transmission tunnel which is essentially at a temperature below 200° C., this vehicle component is heated during the heat-up time to the heat-up temperature (T 1 ). With a starting temperature of below 200° C., but still above room temperature, the residual thermal energy from the hot-forming and press-hardening process is used for the partial heat treatment within the context of the invention.
[0052] Heat-up includes a linear temperature increase as a function of time. After the heat-up time (t 1 ), the heat-up temperature (T 1 ) is maintained during a holding time (t 2 ). The heat-up temperature (T 1 ) is held essentially constant during the entire holding time (t 2 ). Temperature variations in form of a temperature increase or a temperature decrease are not illustrated, but may be implemented within the context of the invention during the holding time (t 2 ) to affect the desired changes in the material structure, but also for cost reasons of the production process.
[0053] At the end of the holding time (t 2 ), a first cooldown to a cooldown temperature (T 2 ) occurs. The temperature hereby decreases linearly during the cooldown time of the first phase (t 3 ) to the cooldown temperature (T 2 ). The cooldown temperature (T 2 ) may be in a range between 100° C. and the heat-up temperature (T 1 ).
[0054] In a subsequent second cooldown phase, an additional linear temperature decrease takes place during the cooldown time of the second phase (t 4 ). The temperature can hereby essentially be lowered to room temperature or to a desired (unillustrated) target temperature. It would also be feasible within the context of the invention to include additional cooldown phases, which are not illustrated.
[0055] FIG. 6 b shows a substantially similar temporal arrangement of the heat treatment, with the difference to FIG. 6 a that the temperature increases progressively during the heat-up time (t 1 ), whereas the temperature steadily decreases with time (t 3 , t 4 ) during the first and second phase of the cooldown.
[0056] FIG. 6 c shows, in addition to FIGS. 6 a and 6 b , that the temperature curve has a diminishing temperature increase during the heat-up time (t 1 ) and that the functional dependence of the temperature decrease over time (t 3 , t 4 ) is progressive during each of the various cooldown phases.
[0057] In the context of the invention, it would also be feasible to combine the temperature dependence over time in mixed forms, such as progressive, linear and diminishing, and to realize a temperature change with progressive, diminishing or linear functional dependence during the holding time (t 2 ).
[0058] While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit and scope of the present invention. The embodiments were chosen and described in order to explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.
[0059] What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims and includes equivalents of the elements recited therein: | A transmission tunnel, in particular for installation in a motor vehicle body, is produced by hot-forming and press-hardening a sheet steel blank, and has a first region which underwent heat treatment, a second region which is not heat-treated, and a transition zone between the first and second regions. The transition zone is hereby defined by a width which is smaller than or equal to 50 mm. At least one component can be coupled to the transmission tunnel to form a floor assembly. | 1 |
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