description
stringlengths 2.98k
3.35M
| abstract
stringlengths 94
10.6k
| cpc
int64 0
8
|
|---|---|---|
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a divisional patent application based upon and claiming the benefit of patent application Ser. No. 10/776,034, filed Feb. 10, 2004, now U.S. Pat. No. 7,476,195, which is a divisional patent application of Ser. No. 09/965,762, filed Sep. 28, 2001, now U.S. Pat. No. 6,689,046, issued Feb. 10, 2004, and is a continuation-in-part of patent application Ser. No. 09/676,336, filed Sep. 29, 2000, now U.S. Pat. No. 6,527,701, issued Mar. 4, 2003, the contents of these applications and patents is incorporated herein by reference thereto.
FIELD OF THE INVENTION
The invention relates to an implantable medical device and a method for the control of fluid flow through a body host canal or vessel, such as a urethra.
BACKGROUND
Incontinence is a condition wherein persons lose control over their voluntary urinary function. The condition can arise from various causes, which include a variety of related and unrelated diseases, aging, and deterioration of the voluntary urethra sphincter muscle. The cost and inconvenience to persons suffering from this condition are great. Several remedies exist that are known in the prior art. Among these, the most common are surgical corrections both minor and major, drugs, devices and diaper capture systems which serve to capture discharges. Another solution is to place a patch over the urinary orifice to prevent unwanted discharge. Possibly, the most effective solution to date is the use of an artificial sphincter. This device is surgically installed and is hydraulically or pneumatically driven, operating by inflation of ballasts to suppress fluid flow. However, control of this device is sometimes difficult and is often inconvenient. Throughout the full range of the available treatment alternatives, the levels of efficacy, useful life, and complications vary greatly, with none of the current treatment alternatives being particularly effective in especially severe cases. Accordingly, there is a need for an improved apparatus to control the loss of voluntary urinary function.
SUMMARY OF THE INVENTION
The present invention overcomes and alleviates the above-mentioned drawbacks and disadvantages in the art through novel implantable body fluid flow control devices for the control of fluid flow through a host body canal or vessel, such as a urethra.
Generally speaking, and in accordance with a first aspect of the invention, an implantable apparatus for controlling fluid flow within a host body comprises a constricting member for allowing fluid flow within a body canal when in an open position and for reducing fluid flow within a body canal when in a closed position, an actuating member for operating the constricting member between said open and closed positions, and control means for operating said actuating member.
Preferably, the constricting member comprises a first engaging element and a second engaging element for coupling to the first engaging element to encircle a body canal. At least one of the first engaging element and the second engaging element preferably has apertures to allow tissue growth therethrough from and to the surface of the body canal. A locking member is preferably provided for locking the first engaging element and second engaging element into the locked position.
The constricting member preferably comprises a plunging member moveable such that the plunging member may apply pressure against said body canal to compress said body canal into said closed position. The actuating member preferably comprises a connector having first- and second ends. The first end of the connector is preferably attached to said plunging member and is axially moveable by said control means to move said plunging member.
The actuating member may comprise a housing whereby the second end of the connector extends slidably through an aperture in the housing and is coupled to an actuator provided in the housing, for example physically or by way of magnetic fields, such that movement of the actuator results in movement of said plunging member away from the body canal to allow at least some fluid flow therethrough. The actuating member preferably comprises a motor operatively coupled to the second end of the connector so that activation of the motor causes the second end of the connector to be axially pulled towards the motor resulting in movement of said plunging member away from the body canal to allow at least some fluid flow therethrough.
A trigger mechanism is preferably provided for activating the motor. The trigger mechanism may be a magnetically operated switch, a radio-controlled circuit, a manually operated button implanted under the patient's skin, or any other suitable trigger mechanism. A manual override system may also be included. The manual override system may include a magnet that can be used outside the patient's body.
A second aspect of the invention provides an implantable apparatus for controlling fluid flow within a host body comprising a constricting member for restricting fluid flow within a body canal when in a closed position, and for allowing fluid flow within the body canal when in an open position; a control mechanism for controlling movement of the constricting member between said open and closed positions; and a link member linking the constricting member and the control mechanism such that the constricting member and the control mechanism are implantable in different parts of the host body.
The control mechanism can be separable from said link member so that said control mechanism may be replaced without removal of the constricting member or the link member from the host body.
Preferably, the link member is adapted for moving said constricting member between said open and closed positions so as to alter fluid flow within the body canal, and an actuating member is preferably provided for actuating said link member. The link member may be a cable provided in a protective sleeve, or may be any other suitable link between the constricting member and the control member such as a wire carrying electronic control signals, a wireless radio communication system, etc.
The actuating member and the control mechanism are preferably provided in a housing separate from the constricting member. The actuating member is preferably a motor, most preferably with a remotely operated trigger mechanism, for example, a magnetically operated trigger mechanism, for activating the motor or magnetic unit from a position outside the patient's body.
The motor or magnetic unit preferably acts through a worm gear. Preferably, the worm gear defines an axis, and the link member is attached to a casing, the worm gear co-operating with a threaded aperture provided in said casing in order to move said casing in a direction parallel to the axis of the worm gear.
According to another aspect of the present invention, there is provided a seal for an elongated link member, the link member extending between an implantable apparatus for implantation in a host body and a control mechanism. The link member extends through an opening in a housing. The seal includes a tubular membrane having two openings, one opening being sealed to the housing, the other opening being sealed to the link member such that fluid entering the housing around the link member is trapped by the membrane. The membrane flexes to allow movement of the shaft.
The membrane is preferably sealed to said link member by gripping means extending around the membrane and the shaft. The gripping means may comprise a coil. The membrane preferably comprises a bellows that folds inwardly when the link member is moved axially away from an interior of the housing, and expands when the link member is moved axially into the housing. The bellows may include a reinforcing ring so that folding of the bellows may be controlled.
According to yet another aspect of the invention, there is provided an operating mechanism for a constricting member for controlling fluid flow in a body canal. The constricting member is actuable between open and closed positions. The operating mechanism includes an axially moveable link member operatively connected to the constricting member for actuating the constricting member. Operating means are provided for axially moving the link member. A coupling for selectively transmitting the axial movement is connected between the link member and the operating means.
The coupling acts so that in one direction there is positive engagement between the operating means and the link member, whereas in an other direction, some play is allowed between the operating means and the link member. The coupling may be used so that opening of the body canal may be achieved by direct actuation of the operating means acting on the link member, but on closing of the body canal, the coupling prevents pressure being directly applied to the body canal by the operating means, thus reducing the likelihood of damage to the body canal.
The coupling may include magnets or a compressible member. A magnet may be attached to the link member, and at least one other magnet may be attached to the operating means. The magnets may be physically moveable towards and away from each other, or they may be electromagnets such that they may be operated when required. The compressible member may be provided in a moveable casing. The link member may be operatively connected to the compressible member, the motor acting to move the casing, and the compressible member acting to move the link member. Alternatively, the coupling may include chain links or a jointed extensible framework, or other means of preventing direct application of pressure to the body canal.
In the case of a coupling comprising magnets, a manual override system may be included, which manual override system comprises a further magnet operable from outside the patient's body. The manual override magnet should be of sufficient strength to move the magnet attached to the link member against the magnetic force of the magnet attached to the operating means.
Another aspect of the invention provides a method of controlling fluid flow within a host body. The method includes implanting a constricting member around a body canal, the constricting member reducing fluid flow in the body vessel when in a closed position. The method further includes implanting a control mechanism in the host body; and providing and implanting a link member between the constricting member and the control mechanism to allow the control mechanism to control the constricting member. The control mechanism may be removed from the host body and replaced without removal of the constricting member and the linking member.
The constricting member may include engaging elements defining an opening therebetween, the method including surrounding the body canal with the engaging elements so that the body canal extends through the opening.
The method may further include suturing the engaging elements to the vessel. In addition, the control mechanism may be implanted remote from the body canal.
Yet a further aspect of the invention includes a remote telemetry system for an implantable apparatus, the telemetry system including a signaling mechanism capable of sending and receiving signals to and from a control unit implanted in a host body in order to monitor the operation of the implantable apparatus, the telemetry system being capable of altering operating settings of the implantable apparatus.
The signals are preferably electromagnetic radiation, most preferably radio signals. The implantable apparatus may include sensors to monitor actions of the implantable apparatus on the host body, and the telemetry system would include a mechanism to interrogate the sensors to provide feedback on the sensed data. Preferably, the sensors are capable of monitoring pressure exerted by a moveable part of the implantable apparatus on a part of the host body, the feedback on the sensed data including commands to alter the range of movement of the moveable part of the implantable apparatus.
Another aspect of the invention includes an implantable apparatus for controlling fluid flow in a host body. The implantable apparatus includes a constricting mechanism including a reciprocable member for selectively applying pressure to a canal of the host body in order to selectively constrict the canal. A pressure sensor is included for detecting the pressure applied by the reciprocable member to the canal. A feedback system is also included for altering movement of said reciprocable member in response to the pressure sensed by said pressure sensor in order to prevent damage to said canal.
The object and advantages of the implantable fluid flow control devices of the present invention permit implantation and use without severing the canal or vessel to be constricted. Moreover, because trauma is minimized with respect to the canal or vessel, and the devices of the present invention are relatively small, lightweight and made of corrosion-resistant material, such as durable plastics, titanium or stainless steel, the devices are suitable for use for extended periods of time to control fluid flow through numerous types of vessels to control, for example, urination, defecation, ejaculation, nutrition absorption for control of obesity, etc. Splitting the fluid flow control device and its control box also provides significant advantages. The surgery to implant the fluid flow control device is delicate and involved, whereas the surgery to implant the control box is much less involved as the control box may be implanted in an easily accessible place, just under the skin of the patient. Thus, when any part of the control box fails, the control box may be removed and replaced with a new control box without needing to adjust the fluid flow control device. The replacement of the control box does not therefore need to be done by a specialist surgeon, and may be performed in a large number of hospitals or even physicians offices under local anaesthetic. The surgery is thus much less traumatic for the patient and may be performed in a location that is convenient for the patient rather than in a hospital that is able to perform specialized urological surgeries.
These and other objects, features and advantages of the present invention may be better understood and appreciated from the following detailed description of the embodiments thereof, selected for purposes of illustration and shown in the accompany drawings. It should therefore be understood that the particular embodiments illustrating the present invention are exemplary only and not to be regarded as limitations of the present invention. In particular, the illustrated embodiment relates to an artificial sphincter for a urethra, but it should be understood that the device can be used with any body fluid flow canal or vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, advantages and features of the present invention, and the manner in which the same are accomplished, will become more readily apparent upon consideration of the following detailed description of the present invention taken in conjunction with the accompany drawings which illustrate a preferred and exemplary embodiment, and wherein:
FIG. 1 is a front exploded view of a body fluid flow control device according to the invention;
FIG. 2 is a side exploded view of the body fluid flow control device of FIG. 1 ;
FIG. 3 is a partial side view of the device of FIG. 1 in the closed position;
FIG. 4 is a partial front view of the device of FIG. 1 in the closed position;
FIG. 5 is a side exploded view of a control box and device for use with a body fluid flow control device;
FIG. 6 is a partial top view of the control box and device of FIG. 5 ;
FIG. 7 is a partial cross-sectional view of a motorized activating member for use with the device of FIG. 1 in the open position;
FIG. 8 is a partial cross-sectional view of the motorized activating member of FIG. 7 in an intermediate position;
FIG. 9 is a partial cross-sectional view of the motorized activating member of FIG. 7 in the closed position;
FIG. 10 is a top partial cross-sectional view of an alternative embodiment of control box and device;
FIG. 11 is an enlarged cross-sectional view of the joint between the cable and link member of FIG. 10 ;
FIG. 12 is a partial cross-sectional view of an alternative embodiment of motorized actuating member;
FIG. 13 is a top partial cross-sectional view of yet a further alternative embodiment of control box and device;
FIG. 14 is a partial cross-sectional view of the control device of FIG. 13 ;
FIG. 15 is a partial cross-sectional view of an alternative means of connecting a link member to a body fluid flow control device; and
FIG. 16 is a partial cross-sectional view of a further alternative means of connecting a link member to a body fluid flow control device.
DETAILED DESCRIPTION OF THE INVENTION
By way of illustrating and providing a more complete appreciation of the present invention and many of the attendant advantages thereof, the following detailed description is given concerning the novel implantable body fluid control device and uses thereof.
Referring now in more detail to the drawings, in which like numerals refer to like parts throughout several views, FIGS. 1-4 show a body fluid flow control device according to the present invention. The body fluid flow control device comprises a first engaging element 102 and a second engaging element 104 . When the first engaging element 102 is coupled with the second engaging element 104 , an inner diameter is formed which is suited for fitting around a host body canal, i.e., any tube or vessel V within the human or animal body, such as the urethra.
The body fluid flow control device also comprises a locking mechanism 106 for locking the first and second engaging elements 102 and 104 together. The locking mechanism 106 may be of any suitable form. In the illustrated embodiment, locking mechanism 106 is in the form of locking pins 108 located on the first engaging element 102 and locking holes 110 located on the second engaging element 104 . In the illustrated embodiment, two locking holes 110 are provided on each side of engaging element 104 . Each locking pin 108 is capable of being attached to either of the locking holes 110 . The inner diameter formed between parts 102 and 104 may thus be adjusted for use with different sized vessels. It should be understood that any other equivalent locking mechanism can be used for this purpose. Alternative locking mechanisms contemplated by the present invention include, but are not limited to, the use of a strap and snap pins or interconnecting molding on the first and second engaging elements 102 and 104 .
The body fluid flow control device of the present invention preferably further includes a piston-like or plunging member 112 located within the inner diameter formed by the coupling of the first and second engaging elements 102 and 104 such that the plunging member 112 may apply pressure against a body canal or vessel, such as a urethra. As can be seen most clearly from FIGS. 2 and 15 , plunging member 112 may have a curved profile such that only outer edges of the plunging member contact the vessel surface in use. This substantially reduces the likelihood of necrosis of the tissue of the vessel because it allows pressure to be placed on the vessel over a smaller area than would be possible with a flat plunging member. The curved profile of plunging member 112 may be provided on a removable plunger head, so that a surgeon may select an appropriately sized plunger head for the size of the vessel.
It should be appreciated that the fluid flow control device may take other forms than that illustrated. For example, instead of a plunging member provided in two engagement members, one of the engagement members could be moveable with respect to the other to compress the vessel in order to restrict fluid flow therein. Alternatively, a fluid flow control device in the form of an artificial external annular sphincter or other means for compressing the vessel may be applied to the vessel.
Apertures 113 may be provided in first engaging element 102 . The apertures 113 permit tissue growth therethrough from and to the surface of the vessel in order to anchor the body fluid control device onto the vessel. Further apertures (not shown) may be provided to allow dissolvable sutures to be used to secure the engaging element to the vessel on a temporary basis, until the engaging element is completely anchored in place by the tissue growth. Alternatively, the material of the engaging element may be such as to allow suturing therethrough, or the engaging element may be otherwise attached to the vessel. It has been found that tissue growth is achieved within a few weeks of implantation of the device into a host body and so it may also be possible to implant the device without any form of attachment to the vessel, and to simply let the tissue growth firmly attach the device to the vessel over time.
All components of the device are made from biologically inert and compatible materials. For example, the fluid flow control device may be made of polypropylene, silicone, titanium, stainless steel and/or Teflon.
An actuating member is utilized by the body fluid flow control device of the present invention to bias the plunging member 112 to apply pressure against the body vessel when the body fluid flow control device is in the closed position, and to pull the plunging member 112 away from the vessel to open the device. The actuating member may comprise a cable 114 covered by a protective sleeve or sheath 116 , the cable 114 having a first end 118 and a second end 120 . Cable 114 is preferably a braided stainless steel cable, although any suitable material may be used. Protective sleeve 116 is preferably made from a bio-compatible material having non-stick properties to discourage tissue growth thereon. A suitable material is Teflon. The cable 114 may be slidably moveable within sleeve 116 , or cable 114 and sleeve 116 may be slidably moveable together.
The first end 118 of the cable 114 runs slidably through an aperture (not shown) in the second engaging element 104 and is attached to the plunging member 112 . A collar 122 is provided around the sleeve 116 where it passes through the aperture in the second engaging element 104 , in order that any tissue growth on and around second engaging element 104 does not interfere with the movement of sleeve 116 through the aperture, if the sleeve 116 is designed to move with cable 114 . If cable 114 is slidably moveable within sleeve 116 , collar 122 prevents tissue ingress into the end of sleeve 116 .
FIGS. 5-9 illustrate a control box for the fluid flow control device that is connected to end 120 of cable 114 . The control box comprises a housing 202 , a motor 204 having a worm gear 206 , a spring 208 and bellows 210 to provide a seal around sleeve 116 . The housing 202 may be made of polypropylene or any other suitable biologically inert material. Batteries 212 are also provided, which should preferably be suitable for implantation in the body, such as batteries manufactured by Wilson Greatbatch Ltd, of Clarence, N.Y., USA. An operating mechanism (not shown) may be provided in the control box, or may be implanted separately in the host body in an easily accessible place.
The arrangement of the control box and cable 114 allows the control box to be implanted in the body separately from the fluid flow control device. For example, the control box may be implanted close to the patient's skin in their abdomen, with the cable 114 and sleeve 116 extending from the control box 202 to the fluid flow control device that is implanted around the urethra or other body vessel.
Cable 114 is attached at end 120 to a nut 216 which is located in the interior of a slidably moveable casing 214 in housing 202 . Spring 208 is also located within casing 214 , which has a threaded aperture 218 to allow worm gear 206 to pass into the interior of casing 214 .
Spring 208 is interposed between the motor 204 and cable 114 in order to provide a coupling for selectively transmitting axial movement from the motor 204 to the cable 114 and hence to the body vessel V, the operation of which is described with reference to FIGS. 7 to 9 below. In the illustrated embodiment, the motor 204 acts on casing 214 to move spring 208 and cable 114 by means of the nut 216 . However, any suitable compressible member may be used in the casing 214 to cushion the vessel from the action of the motor, for example, a resiliently deformable material may be used, or a compressible fluid such as a gas could be used if casing 214 was suitably sealed. Alternatively, a spring or other compressible member may be connected directly to or inserted in cable 114 . Such an arrangement would preferably use a compressible member that was stiff enough so that pushing and pulling motions were still imparted to the cable 114 on operation of the motor.
The slidable casing 214 and worm gear 206 allow axial movement to be imparted to cable 114 by motor 204 , but it should be appreciated that any suitable axial actuation of cable 114 may be used. For example, the motor 204 may have an axially moveable actuator, or suitable gearing could be provided to act on a toothed rack or other axially moveable element. Alternatively, the cable could have a flexible end that may be wound around an axle in housing 202 .
The sleeve 116 containing cable 114 should be sealed to housing 202 to prevent ingress of body fluids from damaging the motor and other components of the control box. Any suitable seal may be used, but it should be noted that where sleeve 116 is designed to be slidably moveable, it is not possible to seal tightly around sleeve 116 , as the sleeve needs to be axially moveable in order to impart movement to plunging member 112 . One method of sealing sleeve 116 to housing 202 is to use a bellows mechanism. A suitable bellows mechanism 210 is illustrated in FIGS. 7-9 . Bellows 210 is designed so that as sleeve 116 moves axially, bellows 210 expands or collapses in on itself so that fluid that seeps into housing 202 around sleeve 116 is captured by bellows 210 , and can be forced back out of the housing 202 when the device is moved to a closed position.
The sleeve 116 may be sealed to bellows 210 and housing 202 by means of a threaded bolt 220 , and a nut 222 . Bolt 220 is passed through an aperture in housing 202 with its head 224 in the interior of the housing. Sleeve 116 passes through and is a close fit with a central bore 226 in bolt 220 . Bellows mechanism 210 is generally tubular and is sealed to the underside of head 224 of bolt 220 by an the O-ring seal 228 . As the nut 222 is tightened on bolt 220 , compression of the O-ring seal 228 causes a tight seal to prevent ingress of fluid into housing 202 around the exterior of bolt 220 . Bellows 210 extends around the head 224 of bolt 220 and is sealed to sleeve 116 in the interior of housing 202 by a tightly wound spring 230 . The spring 230 may be placed onto the bellows 210 before the sleeve 116 is forced through the bellows 210 and spring 230 in order to obtain the tightest seal possible. Other methods of sealing bellows 210 to sleeve 116 include cable clamps, C-clips, adhesive, etc. A reinforcing ring 234 is provided on one surface of bellows 210 , to ensure that the bellows 210 collapses correctly as the sleeve 116 is moved axially. The reinforcing ring 234 may be a thickened area in the wall of the bellows 210 , or may be a separate ring that is attached to the bellows, by gluing or any other suitable means. Instead, or in addition to, the reinforcing ring 234 , the bellows may be pleated or folded in order to ensure correct folding when the fluid flow control device is moved to the closed position.
It should be noted that bellows 210 can be of any suitable shape, provided that a seal is made at the housing and around the sleeve, and that bellows allows movement of the sleeve into and out of the housing. For example, bellows 210 may be a simple tubular shape, with ends of the tube being sealed to the housing and sleeve. Alternatively, bellows 210 may be of a frustoconical shape, or a more complicated shape such as a bell-shape or could be folded or pleated. The seal to the housing could be close to the aperture in the housing through which the seal extends, as illustrated, either inside the housing or outside the housing. Alternatively, the seal could be made to the wall of the housing, around or behind the bolt 220 .
It is possible to seal the sleeve 116 and the housing 202 without using a bellows mechanism, but it has been found that energy losses are created as movement of the sleeve 116 creates friction against the seal. This can cut the battery life of the motor by up to ⅓. For example, a flexible annular ring may be sealed between the sleeve 116 and the housing 202 , the annular ring stretching as the sleeve is axially moved. Alternatively, a series of seals may be provided along sleeve 116 , each seal preventing some fluid ingress to housing 202 .
Control circuitry (not shown in FIGS. 7-9 ) is provided, which operates the motor on receipt of a signal from an operating mechanism. Any of the several well-known control devices can be used to control the operation of the body fluid flow control devices of the present invention by a user so long as the objectives of the present invention are not defeated. Suitable operating mechanisms include radio-control devices, or a magnetic devices that can be sensed by the control circuitry. With a magnetic device, the user may be provided with a separate magnet that they carry with them, and which they position adjacent the skin over the implanted switch when they wish to operate the device. The magnet may be of any suitable shape, and may be shaped for example like a pen or credit card so that its purpose is not immediately apparent to other people. The magnet should have a weak magnetic field so that it must be placed close to the switch in order to operate the device, in order to prevent accidental operation of the device if the magnet is carried in a pocket. Alternatively, a touch sensor, infrared, voice or sound activation may be used, or a manually operated switch may be implanted under the skin of the patient.
A remotely operated operating mechanism is preferred because the device can be operated without irritation to the skin, as would happen with a manually operated trigger. In the preferred embodiment, a manual override switch may be provided in addition to the remotely operated triggering mechanism. The manual override switch is designed to be used temporarily if the control box fails and the user is not close to a physician's office or hospital to have the control box changed. The manual override switch may be provided in the control box, and may be sealed from the interior of the control box until the first activation of the switch, for example by a membrane seal. Such a use of the manual override switch may eventually allow fluid ingress into the control box, which may then need to be replaced. Alternatively, no manual override switch may be provided, which would mean that the user would have to use incontinence pads until the control box could be replaced.
The control circuitry controls operation of the motor, and may detect the position of the plunging member, for example, via the position of the casing or via the drag exerted on the motor. Preferably, the control circuitry also monitors the level of charge in the battery. The control circuitry can be used to initiate opening or prevent closing of the fluid flow control device if a problem such as low battery or a defective motor is detected, so that the device can be caused to remain in the open position. For example, once the device has been opened, an abutment (not shown) may be caused to contact the casing 214 to prevent any further movement thereof. The motor may also be shut off. The device may still be operable by a manual override, as the spring 208 can be compressed and allowed to expand within casing 214 to allow movement of the cable 114 to open and close the device.
The control box 202 may also contain components that allow a physician to interrogate the control circuitry by a remote telemetry system without accessing the box itself. Such components may be interrogated and/or controlled by radio waves or other interactive signals transmitted and received by the telemetry system, or any other suitable mechanism. This allows the physician to check the charge in the batteries, any internal sensors, to alter the tension in the cable 114 , and to make other suitable adjustments. A pressure sensor may be provided on the plunger 112 to monitor the pressure between the plunger 112 and the vessel V when the plunger is in the closed position. The pressure sensor may also be interrogated by the telemetry system, which can then be used to alter the settings for the control device. For example, the number of turns that the motor 204 causes worm gear 206 to make on each operation of the device may be altered in order to set the correct distance of travel of the cable 114 , and hence plunger 112 for any particular patient so as to alleviate any excess pressure exerted on the vessel V. In addition, the telemetry system may include control commands to cause the motor to open and close the body fluid flow control device, either as an override system to the normal operating means, or in addition to the normal operating means in order to test the device in situ.
If the control box causes the device to fail or remain in the open position if a problem is detected, this will simply mean that the patient will return to the condition that they were in before implantation of the device, in other words, in a condition of incontinence. If the device failed in the closed position, the patient would need to be catheterized. However, a manual override system would allow the patient to operate the system manually for a considerable period of time or until medical aid was obtainable.
Actuation of the device is described with reference to FIGS. 7 to 9 . In the open position shown in FIG. 7 , the motor 204 has operated the worm gear 206 to draw casing 214 towards the motor 204 . This pulls nut 216 along with the casing 214 , and thus acts on cable 114 to pull the plunging member 112 away from the vessel V. Bellows 210 is also at its fully extended position. In order to close the fluid control device, the motor 204 is activated to turn worm gear 206 in the opposite direction to that used to open the device. As worm gear 206 is operated, casing 214 is moved away from the motor 204 , spring 208 pushing on nut 216 to bias plunging member 112 against the vessel V, as shown in FIG. 8 . As the motor 204 is operated further, the vessel V prevents plunger 112 moving, and prevents movement of cable 114 and hence nut 216 , due to the increased force needed to move cable 114 against the vessel V when the vessel V is already closed. Nut 216 presses against spring 208 , causing compression of the spring 208 , as shown in FIG. 9 . It can thus be seen that any further movement of worm gear 206 by motor 204 does not result in compression and injury of the vessel V, but the further compression of spring 208 . In this way, axial movement of casing 214 may be selectively transmitted to cable 114 . This protects the vessel V against failure of the device by continuous running of the motor 204 , as the vessel cannot be further compressed due to the interplay between the vessel V and the spring 208 .
An alternative embodiment of the control box is illustrated in FIGS. 10 and 11 . The control box comprises a housing 902 , a motor 904 having a worm gear 906 , a spring 908 and bellows 910 . Batteries 912 are also provided, along with control circuitry (not shown). The spring 908 is located in a slidable spring casing 914 . An operating mechanism (not shown) may be provided in the control box, or may be implanted separately in the host body in an easily accessible place. The spring, worm gear and motor arrangement are as described for FIGS. 5-9 , and will not be further described.
Housing 902 is preferably formed in two pieces, a main body 916 and an end lid 918 . End lid 918 includes a lip 920 that fits inside an end 922 of main body 916 . A groove 924 is provided around lip 920 , in order to receive an 0-ring 926 : End lid 918 is also sonically welded to main body 916 in order to provide a good seal. A groove 928 is provided around the exterior of end 922 of main body 916 , in order to allow for ease of removal of lid 918 with a suitable tool when necessary. An interior housing 930 extends along the length of housing 902 , to one side thereof, in order to separate the motor 904 , worm gear 906 , slidable casing 914 , bellows 910 and other moveable parts from the batteries 912 . Interior housing 930 has a flange 932 at an end 934 remote from end 922 of main body 916 , with an 0-ring groove 936 provided in flange 932 . A set screw 938 is also provided in interior housing 930 , in order to lock motor 904 . Electrical contacts 940 extend to motor 904 from end lid 918 . An internally directed collar 942 having an internal thread extends around flange 932 within housing 902 , and interior housing 930 is secured into housing 902 by means of an externally threaded nut 944 which is screwed into place to hold flange 932 in position. Nut 944 may have pin holes 946 to allow for tightening thereof. An externally directed collar 948 having an internal thread is also provided in housing 902 , in order to allow the cable 114 to pass into interior housing 930 .
Sleeve 116 has an end 950 which is attached to a hollow connector 952 having a first end 954 and a second end 956 . At end 954 , connector 952 has backwardly-directed teeth 958 around the circumference thereof which attach to the inside of sleeve 116 adjacent to end 950 , and act to prevent sleeve 116 from being pulled loose. The second end 956 of connector 952 has an external thread 960 , as well as a groove 962 suitable for receiving an 0-ring 964 . Thread 960 is screwed into the internal thread provided within collar 948 on housing 902 . Cable 114 extends into housing 902 through connector 952 , and is attached at its end 120 to a link member 966 which extends into casing 914 and terminates in nut 216 . The connection between cable 114 and link member 966 is shown enlarged in FIG. 11 . The cable end 120 is fitted into a connector piece 968 that has a tapered end 970 and a groove 972 for receiving a sealing ring. Link member 966 has an opening 974 for receiving connector piece 968 , opening 974 having an internal shoulder 976 . A metal 0-ring 978 is received by shoulder 976 and is held in place by a ring retainer 980 . Connector piece 968 is pushed into opening 974 until the metal 0-ring 978 seats in groove 972 to form a seal between connector piece 968 and link member 966 .
Bellows 910 are attached to housing 902 by means of nut 944 screwed into inwardly directed collar 942 . Bellows 910 has an end flange 982 , which extends adjacent to flange 932 of interior housing 930 , and has an integral 0-ring 984 to seal in 0-ring groove 936 of flange 932 so that bellows 910 is tightly sealed to housing 902 by interior housing 930 . Bellows 910 is also attached to cable link member 966 by means of a cable link 986 , and has a pleated conical shape above flange 982 so that it may fold easily when compressed. It should be noted that in the embodiment of FIG. 10 , the bellows 910 is not attached to the sleeve 116 , as the sleeve 116 is not axially moveable. Instead, cable 114 is axially moveable within sleeve 116 . In this embodiment, bellows 910 may not be necessary, as a good seal may be provided between connector 952 and control box 902 . However, it is advantageous to provide an additional seal, for example using bellows 910 , to prevent fluid ingress into control box 902 .
The operation of the control box of FIG. 10 is the same as for the control box of FIGS. 5 to 9 , and will not be further described.
A further alternative embodiment of a seal for the sleeve and an actuator for the cable is illustrated in FIG. 12 . In the illustrated embodiment, control box 1200 is completely sealed so that no fluid ingress into the box can take place. A hollow cylindrical bore 1202 that is sealed at one end 1204 is formed in control box 1200 . Bore 1202 has internal threads 1206 provided adjacent an outer surface of control box 1200 .
An end of sleeve 116 is attached to a hollow connector 1208 , connector 1208 having an end 1210 and an end 1212 . End 1210 of connector 1208 is dimensioned to pass into the end of sleeve 116 , connector 1208 having outwardly and rearwardly directed teeth 1214 at end 1210 to engage the interior of sleeve 116 , thereby securing connector 1208 to sleeve 116 . End 1212 of connector 1208 is dimensioned to be slightly larger in diameter than sleeve 116 , and has external threads 1216 . Connector 1208 may be screwed into bore 1202 of control box 1200 by means of threads 1216 and 1206 .
End 120 of cable 114 is located in bore 1202 , and is provided with a collar 1218 . An annular magnet 1220 is supported by collar 1218 around end 120 of cable 114 . Cable 114 is axially moveable within sleeve 116 , and therefore a bellows seal is not necessary around sleeve 116 . In addition, as sleeve 116 is not moveable, tissue growth around the sleeve cannot affect the operation of the device.
A motor 1222 has a threaded worm gear 1224 engaged with a casing 1226 through a screw-threaded aperture 1228 located in the bottom of the casing. Casing 1226 extends around bore 1202 , and an annular magnet 1230 is supported around the interior of an upper edge of casing 1226 . Magnet 1230 is aligned with magnet 1220 located on end 120 of cable 114 .
In order to actuate cable 114 to open and close the fluid flow control device, the motor 1222 operates the worm gear 1224 , which moves casing 1226 along the exterior of bore 1202 . Magnet 1230 acts through the plastic material comprising bore 1202 , and causes magnet 1220 to track its movement. This in turn causes cable 114 to be axially moved, operating the fluid flow control device. If the motor 1222 continues operating the worm gear 1224 towards the cable 114 when the body vessel has already been closed, the attraction of magnet 1220 for magnet 1230 is not enough to cause the cable 114 to be moved further, due to resistance from the vessel walls, thus preventing potential damage to the vessel. Thus, axial movement of casing 1226 is selectively transmitted to cable 114 . In addition, the casing 1226 will come to rest against bore 1202 or an interior surface of control box 1200 , preventing the magnets from getting too far out of alignment.
It should be appreciated that a magnetic link between the motor and cable may be achieved in many ways other than that illustrated in FIG. 12 . For example, the magnets need not be annular, but could be placed to one side of the cable. In addition, the magnets need not operate by mutual attractions, but could work by repelling each other to close the vessel, with a spring action or other means operating to open the, vessel once the motor-driven magnet was pulled back towards the motor. With a repelling action, magnets could be placed directly on the ends of the cable and an axially movable actuator driven by the motor.
An alternative embodiment of a magnetic coupling for selectively transmitting axial movement to the cable is illustrated in FIGS. 13 and 14 . These figures illustrate a control box 1300 that is completely sealed. A bore 1302 having a blind end 1304 is provided in the control box 1300 for receiving the end 120 of cable 114 . A connector 1306 is used to connect sleeve 116 to bore 1302 . The connector 1306 has a first end 1308 with rearwardly directed teeth 1310 , a central shoulder 1312 and a second end 1314 having external screw threads 1316 . End 1308 of connector 1306 is pushed into the end of sleeve 116 , the teeth 1310 acting on the inner surface of the sleeve. End 1314 of connector 1306 is connected to control box 1300 by means of an 0-ring seal 1318 and an internally threaded nut 1320 which is threaded onto threads 1316 . Nut 1320 is welded at 1322 to the control box 1300 to form a tight seal.
The cable 114 extends into bore 1302 . A cylindrical magnet 1324 is attached to end 120 of cable 114 by a collar 1326 which is deformed onto the magnet 1324 and cable end 120 for a tight fit. The control box 1300 includes a motor 1328 , a worm gear 1330 and batteries 1332 as described for the FIG. 10 embodiment. A casing 1334 having an annular magnet arrangement 1336 is threaded onto worm gear 1330 , and operates in the same manner as in the FIG. 10 embodiment so will not be further described. Control circuitry including IC's 1338 and other standard components 1340 including resistors and capacitors are also shown.
FIG. 15 illustrates an embodiment of a connector joining first end 118 of cable 114 to the body fluid control device. Connector 1500 has a first end 1502 having outwardly directed teeth 1504 which grip into the inner surface of sleeve 116 . A second end 1506 of connector 1500 has a collar with inwardly directed threads 1508 which are threaded onto outwardly directed threads 1510 on a collar 1512 attached to the body fluid flow control device. An 0-ring 1514 forms a tight seal to the collar 1512 .
FIG. 15 also illustrates plunger 112 in detail. Plunger 112 includes a perforated metal bracket 1516 attached to a metal collar 1518 . The main body of plunger 112 is formed of silicon that is molded onto the perforated bracket 1516 , the silicon extending through the perforations in the bracket to form a tight fit between plunger 112 , bracket 1516 and collar 1518 . Metal collar 1518 may be simply crimped onto end 118 of cable 118 .
FIG. 16 illustrates a further alternative method of connecting cable 114 and sleeve 116 to the body fluid flow control device. In the embodiment of FIG. 16 , the fluid flow control device has a collar 1600 with internal threads 1602 . A connector 1604 is used to connect sleeve 116 to collar 1600 . Connector 1604 has external threads 1606 , a central collar 1608 and outwardly directed teeth 1610 . It should be noted that connector 1604 may be the same as connector 1306 illustrated in FIG. 13 . This allows for economies in manufacture, as only one type of connector need be provided for both ends of the sleeve 116 . A metal collar 1612 is used to connect the plunger (not shown in FIG. 16 ) to end 118 of cable 114 . An 0-ring 1614 may seal between collar 1612 and connector 1604 .
It will be understood that various embodiments of the present invention have been disclosed by way of example and that other modifications and alterations may occur to those skilled in the art without departing from the scope and spirit of the appended claims. Thus, the invention described herein extends to all such modifications and variations as will be apparent to the reader skilled in the art, and also extends to combinations and subcombinations of the features of this description and the accompanying figures. Although preferred embodiments of the present invention have been illustrated in the accompanying figures. and described in the foregoing detailed description, it will be understood that the present invention is not limited the embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the spirit of the present invention as set forth and defined by the following claims, such as for example those embodiments described in non-provisional U.S. patent application Ser. No. 09/048,823, filed Mar. 26, 1998, which is incorporated hereinto in its entirety by reference.
|
An implantable apparatus and a method for controlling fluid flow within a host body, for example for use as an incontinence device. A constricting member is provided for reducing fluid flow within a body canal when in a closed position, and for allowing fluid flow within the body canal when in an open position. In addition, there is a control mechanism for controlling movement of the constricting member between said open and closed positions. A link member links the constricting member and the control mechanism such that the constricting member and the control mechanism are implantable in different parts of the host body. A coupling for selectively transmitting axial movement to the link member may be provided between the link member and the control mechanism so that the constricting member cannot apply a damaging amount of force to the body canal.
| 0
|
CROSS-REFERENCE
[0001] The present application claims the benefit of U.S. Provisional Application No. 60/664,128, filed Mar. 22, 2005, the disclosure of which is hereby incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to embossing seals and more particularly relates to mechanically assisted embossing seals.
BACKGROUND OF THE INVENTION
[0003] For many years, seals have been placed on documents to verify their authenticity. One of the earliest seals was created by placing wax on a document and then pressing the face of a ring into the wax. When the document was later presented to a third party, the authenticity of the document was verified by analyzing the image or symbol formed in the wax. Today, seals are created using a press-like device that stamps an image onto a document. Such seals are generally found on government documents such as birth certificates, death certificates and marriage licenses, as well as other documents such as architectural drawings and notarized documents.
[0004] Most conventional embossing seals have a die and an opposing counter that move toward one another for forming an image on an article. On the die, the image is depressed from a generally planar surface. The counter also has an image, which mirrors the image that is on the stamping die. The die and the counter can be made using a variety of methods that are well known to those skilled in the art. Typically the die and counter are arranged so that the image created on the document can be read from left to right. In the alternative, the image can be produced so that it can be read from left to right from the debossed side of the document.
[0005] In order to place a seal on a document, the item is placed between the die and the counter. The die and counter are then moved toward one another until the opposing elements are separated by only the thickness of the document. Further movement of the die and the counter toward one another results in the raised image on the counter forcing a portion of the article into the depressed image on the die. At maximum pressure, the raised image on the counter and the depressed image on the die are fully engaged with the article for selectively stretching and depressing the image onto the article. If the pressure applied is sufficient to cause the material of the article to stretch or yield, a permanent, precisely formed, raised image will result on one side of the article. The opposite side of the article will have a debossed mirror image of the raised image.
[0006] An embossed or debossed image can be formed on almost any type of flexible, deformable material. At one end of the spectrum, the deformable material may made of metal such as a malleable metal sheet or a metal block. At the other end of the spectrum, the deformable material may be gossamer-like paper. As noted above, the most common articles to be embossed include commercial paper stock used for legal documents, architectural or engineering drawings, government documents, letterhead, envelopes and the like.
[0007] There are generally two types of embossing seals: desk seals and pocket seals. Desk seals are typically large, ornate devices that are designed to both impress the observer and to effectively impress a seal onto a document. Size and portability are not major concerns with desk seals. As a result, mechanical features such as levers can be added to a desk seal to make the stamping procedure easier for an operator, without concern for the overall size or weight of the device.
[0008] The second type of seal, a pocket seal, offers the same functionality as desk seals, but in a more compact design. As the term suggests, pocket seals are small enough to fit inside a typical pocket. Pocket seals may also be small enough to fit within a briefcase, a pocketbook, or a three-ring binder. Because of their portability, pocket seals can be easily transported from one location to another, which provides a distinct advantage over stationary desk seals.
[0009] The small size of pocket seals is both an advantage and a drawback. While large desk seals can provide a significant mechanical advantage through various drive mechanisms, the operation of a pocket seal relies primarily on hand strength to create the embossed seal.
[0010] As noted above, the paper stock of the document to be sealed can vary greatly in weight and thickness, as well as in fiber type and content. The denser and thicker the paper, the more force that is required to produce an image. As a result, individuals using pocket seals are frequently faced with fatigue and potential repetitive motion injuries from the constant strain placed on the hand and wrist during the operation. Those afflicted with weak hand muscles, arthritis, or other physical ailments will be limited in their use of a conventional pocket seal. Some individuals may be forced into using the more cumbersome, stationary desk seals. In situations where the use of a desk seal is not possible, however, no other option is readily available.
[0011] When seals are placed on documents, it may be necessary to position and/or align the seal over a particular region of a document. For example, it may be necessary to place a seal at the bottom edge of a document. If the same seal were used to affix a seal to the top edge of another document, e.g. for letterhead, the image would be inverted. Likewise, if the seal were used on the right-hand edge of a document, the image would be turned 90 degrees from the normal reading position. In either of these two latter conditions, the seal image would be difficult to read.
[0012] Conventional pocket seal presses have two opposing arms that are pivotally connected with one another. The two arms are compressible toward one another for moving the sealing ends of the arms toward one another. The die and the counter are typically attached to the opposing arms, at the sealing ends of the respective arms. The die and the counter are normally held apart by one or more springs, which may include one or more leaf springs. The structure of the holder allows the opposing faces of the die and the counter to move normal to one another while preventing the opposing faces from moving parallel to one another. Thus, once the die and the counter are properly oriented and assembled with the holder, the die and counter cannot become misaligned.
[0013] With the die and counter thus connected, the one or more leaf springs define a throat that limits how far from the edge of a sheet the seal can be made. If the throat is not deep enough, the pocket seal cannot produce a correct-reading image located at an interior region of the embossed article. Even if a seal press could be built that has a sufficiently deep throat, a deep throat causes a myriad of insurmountable problems with the seal press as well as with the geometry between the die and counter.
[0014] Thus, there is a need for a seal that is easy to operate and that reduces the level of manual force required to produce a suitable raised image. There is also a need for an embossing seal having a die and counter that can be positioned in a number of different orientations to allow correctly aligned images to be produced on documents, regardless of the orientation of the seal press relative to the document. There is also a need for an embossing seal with a sufficiently deep throat to allow placement of a seal in an interior region of a document.
[0015] There is also a need for a seal that enables the die and the counter to be interchanged so that the counter comes in contact with the face of the document and displaces the article into the engraved areas of the die on the opposite side. By doing so, an image readable from left to right can be formed on the debossed side of the document.
[0016] There is also a need for a seal that embosses or debosses images into certain materials that are not in sheet form, such as a block of wood or metal. There is also a need for an embossing seal that can be used to form images on both documents, such as paper documents, and harder items such as metal blocks.
SUMMARY OF THE INVENTION
[0017] In certain preferred embodiments of the present invention, an embossing seal includes a frame, a die exposed at an underside of the frame, and a handle connected to the frame. The handle is desirably movable between an extended position and a depressed position. The embossing seal also desirably includes an impact element movable from a first position in contact with the die to a second position spaced from the die. A spring is preferably coupled with the impact element for normally urging the impact element into the first position, against the die. The spring is preferably deflectable for storing energy. The spring can have any design so long as it is able to store energy and release energy. The spring may include two or more springs in contact with the impact element. The spring may be a coil spring having one or more coils.
[0018] The embossing seal also preferably includes a lever linking the handle to the impact element. In operation, movement of the handle from the extended position toward the depressed position causes the lever to move the impact element from the first position to the second position for deflecting and storing energy in the spring. In other preferred embodiments, the handle may incorporate the features found in the lever so that there is not a need for an additional item such as a lever. After the initial downward movement of the handle, further movement of the handle toward the depressed position causes the lever to release the impact element so that the energy stored in the deflected spring is transferred to the impact element for moving the impact element back to the first position against the die. Due to the energy transferred from the spring to the impact element, the impact element strikes the die with a sufficient force to transfer an image from the die to an article abutted against the die.
[0019] In certain preferred embodiments, the die may include a die support that is attached to the frame and the die attached to the die support. The die is preferably detachably connected with the frame so that it can be removed from contact with the seal and later re-attached to the seal. In still other preferred embodiments, the angular orientation of the die relative to the frame may be changeable. In highly preferred embodiments, the angular orientation can be set at zero, 90, 180 and 270 degrees. I still other preferred embodiments, the angular orientation can be set at additional angles such as 45 degrees, 225 degrees, etc. In still other preferred embodiments having both a die and a counter, the energy transferred from the impact element to the die presses a seal on an article positioned between the die and the counter. The embossing seal may be a pocket seal or a desk seal. The counter is preferably detachably connected with the base and angularly rotatable relative to the base as described above for the die. The counter may be directly attachable to the base or may be coupled with the base using a counter support.
[0020] In certain preferred embodiments, the embossing seal includes a counter opposing the die. The counter and the die are desirably movable toward one another for embossing a seal on an item. The die may have a first image formed thereon and the counter may have a second image formed thereon that is a mirror image of the first image. One of the first and second images is preferably raised and one of the first and second images in preferably depressed. The die and the counter may be rotatable to one or more fixed positions for selectively aligning the first and second images of the respective die and counter with an item placed between the die and the counter. The die and the counter may have alignment tabs provided thereon that may be used to properly align the image with an article, such as a document.
[0021] The handle may be pivotally attached to the frame and the frame may be pivotally attached to a base that supports the seal device. In certain preferred embodiments, the spring has a first end connected to the impact element and a second end connected to the frame. The first and second ends of the spring may define a distance that is adjustable for adjusting the tension of the spring and/or the level of energy that may be stored in the spring. In other preferred embodiments, a second spring in contact with the impact element may be added. In still other preferred embodiments, more than two springs may be in contact with the impact element for normally urging the impact element to remain in contact with the die or die support.
[0022] The impact element can have any shape and/or size required for effectively transferring energy or striking force from a spring to the die. In certain preferred embodiments, the impact element has a bottom face that is adapted to selectively strike a backside of the die or die support for transferring energy from the impact element to the die. In certain preferred embodiments, the impact element includes an upper end, the bottom face, and a reduced diameter area between the upper end and the bottom face. The reduced diameter may be an undercut area or a neck that defines an upper shoulder and a lower shoulder. The lever desirably includes a tip end that is adapted to engage the reduced diameter area or the upper shoulder of the impact element for selectively moving the impact element away from the die. The lever is preferably adapted to pivot relative to the frame for urging the tip end of the lever into contact with the impact element, and providing leverage as the tip end urges the impact element away from the die.
[0023] In certain preferred embodiments, the embossing seal includes a lever return spring in contact with the lever for returning the lever from the depressed position to the extended position. The lever may have a first end including the tip end and a second end remote therefrom. The lever may have a notch adjacent the second end thereof that is adapted to receive the lever return spring.
[0024] The embossing seal may also have a base pivotally connected with the frame and a base return spring positioned between the frame and the base for urging the frame from a frame depressed position to a frame extended position.
[0025] In still other preferred embodiments of the present invention, an embossing seal includes a frame, a die exposed at an underside of the frame, and a base pivotally connected to the frame, the base including a counter that opposes the die. The embossing seal also desirably includes a handle pivotally connected to the frame, the handle being movable between an extended position and a depressed position, an impact element disposed in the frame and being movable from a first position in contact with the die to a second position spaced from the die, and a spring coupled with the impact element for normally urging the impact element against the die. The spring is preferably deflectable for storing energy. The embossing seal also preferably includes a lever pivotally attached to the frame and linking the handle to the impact element. During operation, initial movement of the handle from the handle extended position toward the handle depressed position causes the lever to lift the impact element away from the die for deflecting and storing energy in the spring that is coupled with the impact element. Further movement of the handle toward the handle depressed position causes the lever to release the impact element, thereby transferring the energy stored in the spring to the impact element for urging the impact element against the die with a striking force.
[0026] In certain preferred embodiments, the spring has a first end connected with the impact element and a second end connected with the frame, whereby the spring is deflectable for storing energy therein. The first and second ends of the spring are movable toward one another for adjusting the amount of energy that is storable in the spring.
[0027] Although the invention is primarily directed to use in pocket seals, there is also a need for such an effort-saving improvement for desk seals. Repetitive use of these devices can lead to physical strain, fatigue and possible injury. Thus, the present invention is appropriate for use in desk seals as well.
[0028] For simplicity, the discussion herein generally refers to the article being embossed as paper. It is understood, however, that the scope of the invention is broadly applicable to any resilient, flexible materials in sheet form. The present invention may also be used to place seals on larger items such as blocks of metal and wood. For these larger items, the base of the embossing seal may be rotated relative to the frame to enable the die to be abutted against a surface of the larger object.
[0029] A mechanical advantage may be obtained in the present invention through the use of one or more linkages or levers. In the embossing seal device disclosed in the present application, manual pressure is exerted on the seal press to urge the die and counter elements toward each other. Once the article (e.g. document) is securely pressed between the die and the counter, additional force applied to the seal device begins the embossing process and also begins to raise the impact element against the force of an energy-storing element. In one preferred embodiment, the energy-storing element is a torsion spring. However, the energy-storing element can be any component that effectively stores energy, and then releases energy to the impact element. When the impact element is at a predetermined distance or position relative to the die, the impact element is released for striking an area on the back of the die for imparting a striking force on the die. With appropriately chosen mechanical elements, the impact force delivered may be significantly higher than the force required to load the energy-storing element. In highly preferred embodiments of the present invention, the energy-storing element may be adjusted to selectively control the magnitude of the impact force applied by the impact element. The adjustment feature allows the user to select the force exerted on the document to achieve a desirable image on any type of paper stock or sheet material.
[0030] These and other preferred embodiments of the present invention will be described in more detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 shows a perspective view of an embossing seal having a depressible handle, in accordance with certain preferred embodiments to the present invention.
[0032] FIG. 2A shows a cross sectional view of the embossing seal shown in FIG. 1 .
[0033] FIG. 2B shows an expanded view of a portion of the embossing seal shown in FIG. 2A .
[0034] FIG. 3 shows another cross sectional view of the embossing seal shown in FIG. 1 with the handle being slightly depressed.
[0035] FIG. 4 shows a cross sectional view of the embossing seal of FIG. 3 after the handle has been depressed further from the position shown in FIG. 3 .
[0036] FIG. 5 shows a cross sectional view of the embossing seal of FIG. 4 after the handle has been depressed further from the position shown in FIG. 4 .
[0037] FIG. 6 shows a cross sectional view of the embossing seal of FIG. 5 after the handle has been depressed further from the position shown in FIG. 5 .
[0038] FIG. 7 shows a cross sectional view of the embossing seal of FIG. 1 with a base of the seal rotated relative to a frame of the seal.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0039] Referring to FIG. 1 , in certain preferred embodiments of the present invention, an embossing seal 10 includes a handle 20 that is pivotally connected to a frame 22 , which, in turn, is pivotally connected to a base 24 . The handle 20 includes a leading end 26 and a trailing end 28 remote therefrom. The frame 22 has a leading end 30 and a trailing end 32 remote therefrom. The leading end 26 of the handle 20 is pivotally connected with the leading end 30 of frame 22 via a pivot element 34 . The frame 22 has a first half 36 that may be assembled with a second half 38 . The two halves 36 , 38 may be assembled using any one of a number of attachment devices such as a tongue-in-groove arrangement, pins insertible into depressions, screws, adhesive, etc.
[0040] The base 24 preferably includes a leading end 40 and a trailing end 42 remote therefrom. The trailing end 42 of the base 24 includes a pair of vertically extending legs 44 , 46 . The base 24 also desirably includes a first half 48 that may be assembled with a second half 50 using the assembly elements described above. In other preferred embodiments, the base may be made of one piece or may be made of two or more pieces that are assembled together.
[0041] Any one of the handle 20 , the frame 22 and the base 24 may be made from structurally rigid materials such as, structurally rigid plastic resins. In certain preferred embodiments, any one of the handle 20 , frame 22 and base 24 components may be made from plastic resins such as polycarbonate, acrylonitrile butadiene styrene (ABS), glass-filled nylon, etc. In still other preferred embodiments of the present invention, the elements may be made from metal or metal alloys.
[0042] The pivot element 34 preferably projects from the frame 22 , at the leading end 30 of the frame 22 and perpendicular to a longitudinal axis of the frame 22 . The pivot element 34 may be a single pin that extends through the frame or may be formed as two components, with each half projecting from one of the halves 36 , 38 of the frame 22 . A second pivoting element (not shown) is provided at the trailing end 32 of the frame 22 for pivotally connecting the frame 22 to the trailing end 48 of base 24 .
[0043] Referring to FIGS. 1 and 2 A, handle 20 has a substantially U-shaped underside 52 . Referring to FIG. 2A , the inside surface 54 of handle 20 includes a boss 56 projecting therefrom. The boss 56 includes a first surface 58 that extends in a direction substantially parallel to the inside surface 54 of handle 20 . The boss 56 also includes a second surface 60 that extends diagonally relative to inside surface 54 and first surface 58 .
[0044] Referring to FIG. 2B , the base 24 has a top surface 62 and a bottom surface 64 . The base may be adapted for sitting atop a flat surface such as a tabletop. In other preferred embodiments, the base may be adapted for engagement by a user's hand. Thus, the seal disclosed in the present application may be a pocket seal or a desk seal. The leading end 40 of the base 24 desirably has a first recess 66 formed in the top surface 62 . The recess 66 also includes two or more pockets 68 that extend below the floor of recess 66 . The base also desirably includes a second recess 70 that extends from the bottom surface 64 toward the top surface 62 . The second recess is preferably centrally located relative to the first recess 66 . In other words, the second recess 70 may be located equidistant from the two or more pockets 68 .
[0045] The embossing seal 10 also desirably includes a counter support 72 having a top surface 74 and a bottom surface 76 . The bottom surface 76 includes one or more projections 78 extending therefrom that are adapted to fit within the two or more pockets 68 . The bottom surface of the counter support 72 also includes a centrally located anchoring element 80 projecting therefrom. During assembly, the central anchor 80 is received within centrally located second recess 70 and the one or more projections 78 are received within the two or more pockets 68 . As a result, the counter support 72 is reliably secured to the base 24 . In certain preferred embodiments, the counter support 72 is able to rotate relative to the base after being attached thereto.
[0046] The embossing seal 10 also preferably includes a counter 82 that is connected with the counter support 72 . The counter 82 has a top face 84 that preferably contains a portion of a seal.
[0047] The frame 22 preferably includes a die mounting surface 86 including a die mounting face 88 having die mounting pockets 90 formed therein. The seal 10 also desirably includes a die support 92 having one or more projections 94 formed on a first face 96 thereof. The one or more projections 94 are preferably received within the die mounting pockets 90 for holding the die support 92 affixed to the leading end 30 of the frame 22 . Embossing seal 10 also desirably includes die 98 having a face 100 adapted to oppose and abut against the top face 84 of counter 82 .
[0048] In other preferred embodiments of the present invention, the die is attached directly to the frame and the counter is attached directly to the base. In these particular preferred embodiments, there may be no die support and/or counter support.
[0049] In the particular preferred embodiment shown in FIGS. 1, 2A and 2 B, the die 98 and counter 82 are circular in shape. In other preferred embodiments, however, the die and counter have other shapes. The die and counter may be rotated so that they can be aligned with an article to be sealed. In certain preferred embodiments, the die and counter can be rotated at zero, 90, 180 and 270 degrees so that the seal image can be properly aligned with a document. The projections 78 , 94 on the respective counter support 72 and the die support 92 , are preferably received by the pockets 68 and 90 , for holding the counter and die at the particular zero, 90, 180 and 270 degree angle selected by a user.
[0050] In operation, the projections 78 on the bottom face of the counter support 72 are sized and shaped so that the counter support 72 can be displaced vertically and rotated relative to the base 24 without disengaging the central projection 80 from its attachment to central recess 70 . As a result, the counter support 72 is able to rotate relative to the base 24 without becoming disengaged from base 24 . The die support can be rotated in a similar manner. The counter and the die may have alignment marks that indicate the angle at which the counter and die have been set. The alignment marks preferably insure that the die and counter are properly aligned with one another and/or the document being sealed.
[0051] Referring to FIGS. 2A and 3 , the embossing seal 10 preferably includes a lever 102 having a leading end 104 and a trailing end 106 . The leading end 104 includes a lever tip 108 including a ledge 110 and the trailing end 106 includes a notch 112 . The lever 102 also includes a lever slot 114 having elongated sidewalls 116 . Embossing seal 10 also preferably includes a lever pivot element 118 that is captured within the lever slot 114 . The lever pivot element 118 enables the lever to move between the fully extended position shown in FIG. 2A and a depressed position shown in FIG. 6 .
[0052] Referring to FIGS. 2A and 3 , the embossing seal 10 also preferably includes a torsion spring 120 having a leading end 122 and a trailing end 124 . The torsion spring 120 has a center coil 126 that facilitates compression and expansion thereof. The center coil 126 of torsion spring 120 preferably does not engage lever pivot element 118 during operation of the seal.
[0053] In certain preferred embodiments, the torsion spring has a pair of leading ends that are spaced from one another and that are connected to the impact element. In other preferred embodiments, the center coil 126 may include two or more coils for increasing the amount of energy that may be stored in the torsion spring. In still other preferred embodiments, a first torsion spring may be provided on one side of the lever and a second torsion spring may be provided on another side of the lever for balancing the forces exerted upon the impact element.
[0054] Referring to FIGS. 2A, 2B and 3 , embossing seal 10 also preferably includes an impact element 128 having a lower end 130 , an upper end 132 , and a reduced diameter neck 134 defining an upper shoulder 136 and a lower shoulder 138 . The impact element 128 also desirably includes at least one opening 140 ( FIG. 2A ) that receives at least one leading end 122 of torsion spring 120 . The impact element 128 is adapted for sliding movement along a vertical axis designated X-X ( FIG. 3 ).
[0055] Referring to FIGS. 2A and 3 , the embossing seal 10 also preferably includes a lever return spring 142 having a first end 144 engaging notch 112 of lever 102 and a second end 146 secured to the frame 22 of the seal. The lever return spring 142 also includes one or more center coils 148 that enable the lever return spring to store energy for returning the lever to its original state after being compressed.
[0056] Embossing seal 10 also includes a frame return spring 150 having a lower end 152 in contact with base 24 and an upper end 154 in contact with frame 22 . The frame return spring 150 is adapted to return the frame to its original idle position after the handle and frame have been depressed.
[0057] Referring to FIGS. 2A and 2B , initially the strike face 100 of die 98 is not in contact with the top face 84 of counter 82 . In order to form a seal on an item such as a document or sheet, the item is placed between the die 98 and the counter 82 . Initially, when the handle is in the extended position shown in FIG. 2A , the lever pivot element 118 is located at the forward end of the slot 114 of lever 102 . When downward pressure is applied on the handle 20 , the lever 102 is urged forward so that the tip end 108 is urged into contact with the impact element. Referring to FIG. 3 , when tip 110 of lever 102 is positioned in engagement with the upper shoulder 136 of impact element 128 , the handle may be pivoted downwardly toward base 24 . The boss 56 of handle 20 urges the lever 102 to pivot about the lever pivot element 118 . Such action causes the tip 108 of the lever 102 to urge the bottom face 130 of the impact element 128 away from the die 98 .
[0058] Referring to FIG. 4 , further downward movement of the handle 20 urges the lever 102 and the tip end 108 of the lever to pivot further. This movement further elevates the bottom face 130 of the impact element 128 above the die 98 . As the lever 102 is being pivoted, the torsion spring 120 is being compressed, thereby storing energy in the torsion spring. In addition, compression force is being stored in lever return spring 142 . At this point, the energy cannot be released from the springs 120 , 142 because the tip end 108 of the lever 102 prevents the impact element 128 from moving back toward the die 98 .
[0059] Referring to FIGS. 4 and 5 , as the handle is depressed still further, the tip end 108 of the lever 102 moves toward the outer perimeter of the upper shoulder 136 of the impact element 128 . During this further movement, additional compression energy is stored in torsion spring 120 and lever return spring 142 .
[0060] Referring to FIG. 6 , after lever 102 pivots even further, the tip end 108 of the lever 102 releases the upper shoulder 136 of the impact element 128 . Once the tip end 108 releases the upper shoulder 136 , the impact element 128 is free to move downwardly along the axis designated X-X ( FIG. 3 ), due primarily to the energy that has been stored in torsion spring 120 . Once the tip end 108 of the lever 102 releases the upper shoulder 136 , the torsion spring 120 forces the impact element 128 downwardly toward the die support 92 which transfers the force to the die 98 intimately connected therewith. The force exerted upon the die 98 by the impact element 128 will emboss an item (not shown), such as a paper document, positioned between the die 98 and the counter 82 .
[0061] After an item has been sealed, the handle 20 can be released. At this time, the lever return spring 42 will release the energy stored therein for moving the handle back to the position shown in FIG. 1 . As shown in FIG. 6 , the first end 144 of the lever return spring 142 will push upwardly on notch 112 formed at the trailing end 106 of the lever 102 , which, in turn, forces the handle to return to the original position shown in FIGS. 1 and 2 A. In addition, the frame return spring 150 ( FIG. 2A ) will transfer stored energy to the frame and the base for returning the frame back to the idle or extended position shown in FIG. 2A .
[0062] Referring to FIG. 7 , in certain preferred embodiments of the present invention, the item to be embossed may be too large to fit between the frame 22 and the base 24 . For example, a seal may have to be placed on a block 200 . In this instance, the base 24 may be rotated to the position shown in FIG. 7 . After rotating the base 24 to the position shown in FIG. 7 , the die 298 may be positioned over a surface 202 of the block 200 . The embossing seal may then be operated as described above for forming a seal on the surface 202 of the block 200 .
[0063] As these and other variations and combinations of the features set forth above can be utilized, the foregoing description of the preferred embodiment should be taken by way of illustration rather than by limitation of the invention.
|
An embossing seal includes a frame, a die exposed at an underside of the frame, and a handle connected to the frame, the handle being movable between an extended position and a depressed position. The embossing seal includes an impact element movable from a first position in contact with the die to a second position spaced from the die, and a spring coupled with the impact element for normally urging the impact element into the first position, the spring being deflectable for storing energy. The embossing seal also has a lever linking the handle to the impact element. In operation, movement of the handle from the extended position toward the depressed position causes the lever to move the impact element from the first position to the second position for deflecting and storing energy in the spring. Further movement of the handle toward the depressed position causes the lever to release the impact element so that the energy stored in the deflected spring is transferred to the impact element for moving the impact element back to the first position so that the impact element strikes the die with a striking force.
| 1
|
BACKGROUND OF THE INVENTION
This invention relates to an austenitic, corrosion resistant steel alloy and in particular to such an alloy and articles made therefrom having good high temperature strength in combination with good wear resistance.
Efforts to improve the performance and durability of internal combustion engines have resulted in a demand for materials which can withstand the corrosive, high temperature, and high stress conditions of such engines. Of the many components which make up modern day gasoline and diesel engines, the exhaust valves are subjected to all of the foregoing conditions when in use. Among the properties desired of materials for fabricating exhaust valves for high performance, heavy duty, internal combustion engines are good high temperature strength and hardness, resistance to oxidation and hot corrosion, good wear resistance and good formability.
U.S. Pat. No. 3,969,109 granted July 12, 1976 to H. Tanczyn relates to an austenitic stainless steel having the following composition in weight percent (w/o). Here and throughout this application, percent will be by weight unless otherwise indicated.
______________________________________Element w/o______________________________________C 0.20-0.50Mn 0.01-3.0Si 2 max.P 0.10 max.S 0.40 max.Cr 18-35Ni 0.01-15N 0.30-1.0Fe Balance______________________________________
Included with the balance are the usual incidental amounts of other elements present in commercial grades of such steels. Tanczyn also suggests that up to 4 w/o molybdenum, or up to 3% tungsten can be added to the alloy. Tanczyn further states that columbium and/or vanadium may be added to the alloy in amounts up to 2% total. The alloy which is described in the Tanczyn patent has been used to make exhaust valves for high performance, heavy duty automotive engines.
An alloy designated as "23-8N" has been sold containing about 0.28-0.38% C, 1.5-3.5% Mn, 0.5-1.0% Si, 0.04% max. P, 0.03% max. S, 22.0-24.0% Cr, 7.0-9.0% Ni, 0.25-0.40% N, and the balance of essentially iron. "23-8N" alloy leaves something to be desired, however, with respect to wear resistance. Under severe service conditions, exhaust valves form the 23-8N alloy are subject to undesirable wear due to the metal-to-metal contact between the valve head and seat unless hard faced to obtain better wear resistance.
U.S. Pat. No. 3,561,953, granted February 9, 1971 to I. Niimi et al. relates to an austenitic steel alloy containing nickel, chromium, manganese, molybdenum and vanadium. The broad range of the alloy described in Niimi et al. is as follows:
______________________________________Element w/o______________________________________C 0.1-0.6Mn 3.0-15.0Si 0.1-2.0Cr 15.0-28.0Ni 1.0-15.0Mo 0.01-1.5V 0.01-1.5N 0.2-0.6W 0.01-2.0Cb 0.01-1.5Ca 0.001-0.020O <0.008Fe Balance______________________________________
The balance includes usual amounts of incidental elements present in commercial grades of such steels. Niimi et al states that the alloy is "for engine valves and similar applications". However, Niimi et al. does not address the problem of adhesive wear resistance in automotive exhaust valves. Furthermore, Niimi et al. states that V and Mo adversely affect the hot workability of the alloy. Niimi et al. is directed to an alloy in which oxygen content is severely limited and which relies on the use of a small amount of calcium to improve the hot workability of the alloy.
U.S. Pat. No. 3,366,472 granted on January 30, 1968 to H. Tanczyn et al. relates to an austenitic stainless steel alloy containing chromium, nickel, manganese, vanadium, carbon and nitrogen. The broad compositional range of the alloy described in Tanczyn et al. is as follows:
______________________________________Element w/o Range______________________________________C 0.20-1.50Mn 0.01-16.00Si 1.25 max.P 0.050 max.S 0.35 max.Cr 12-30Ni 0.01-7Mo 4.00 max.V 0.50-2.00N 0.15-0.75B Up to 0.005W 4.00 max.Cb 1.50 max.Cu 4.00 max.Fe Balance______________________________________
and in which the sum of w/o nickel and w/o manganese must be at least 6%. Included with the balance are the usual amounts of other elements present in commercial grades of such steels. The alloy described in the Tanczyn et al. patent is indicated as being heat hardenable and to have high strength at both room and elevated temperatures in both the solution treated and age-hardened condition, although only room temperature strength is indicated. However, the alloy of Tanczyn et al. is believed to provide less than desirable hardness and wear resistance at elevated temperatures. hardness and wear resistance at elevated temperatures.
SUMMARY OF THE INVENTION
In accordance with this invention, a precipitation strengthenable, austenitic steel alloy and article made therefrom, are provided having mechanical properties and corrosion resistance properties comparable to 23-8N but with improved heat resistance and elevated temperature wear resistance. The alloy of this invention consists essentially of, in weight percent, about:
______________________________________ Broad Intermediate Preferred______________________________________C 1.50 max. 0.35-0.90 0.40-0.80Mn 3.0-10.0 4.0-8.5 4.5-8.0Si 2.0 max. 0.75 max. 0.50 max.Cr 18-28 19.0-25.0 20.0-24.0Ni 3.0-10.0 4.5-8.5 5.0-8.5Mo Up to 10.0 Up to 8.0 0.5 max.V Up to 4.0 0.5-3.5 0.75-3.0B Up to 0.03 Up to 0.02 0.001-0.015N 1.0 max. 0.25-0.85 0.35-0.75W Up to 8.0 Up to 6.0 0.5 max.Fe Bal. Bal. Bal.______________________________________
Included with the balance (Bal.) are incidental impurities and additions which do not detract from the desired properties. For example, up to about 0.10 w/o, preferably 0.05 w/o max. phosphorus; up to about 0.05 w/o, preferably 0.015 w/o max. sulfur; and up to about 1.0 max. w/o, better yet no more than about 0.85 w/o, and preferably about 0.5 w/o max. niobium can be present. Up to about 0.05 w/o aluminum and up to about 0.01 w/o of each of the elements calcium and magnesium can be present as residuals from deoxidizing and/or desulfurizing additions. Varying amounts of titanium and/or zirconium may also be present in stoichiometric proportions as additional carbide, nitride and carbonitride forming elements.
The foregoing tabulation is provided as a convenient summary and is not intended thereby to restrict the lower and upper values of the ranges of the individual elements of the alloy of this invention for use solely in combination with each other or to restrict the broad, intermediate or preferred ranges of the elements for use solely in combination with each other. Thus, one or more of the broad, intermediate and preferred ranges can be used with one or more of the other ranges for the remaining elements. In addition, a broad, intermediate or preferred minimum or maximum for an element can be used with the maximum or minimum for that element from one of the remaining ranges.
In the iron base steel alloy of this invention carbon, nitrogen, vanadium and molybdenum are critically balanced to provide improved high temperature strength and wear resistance with a substantially austenitic microstructure. In this regard w/o C+w/o N must be at least about 0.7, preferably at least about 0.8 and w/o V+0.5 (w/o Mo)+0.25 (w/o W) must be about 0.8-9.0, preferably about 1.0-6.0. In order to provide the best properties the alloy is balanced in accordance with the following relationships:
(w/o C+w/o N)≧[0.65+0.15 (w/o V)+0.04 (w/o Mo+0.5 (w/o W))], and
(w/o C+w/o N)≦[0.65+0.38 (w/o V)+0.08 (w/o Mo+0.5 (w/o W))].
Additionally, w/o Mn+w/o Ni is about 6.0-16.0 and preferably about 10.00-15.00 to ensure an essentially austenitic structure.
DETAILED DESCRIPTION OF THE INVENTION
Vanadium and molybdenum, either individually or in combination, work to provide the desired high hardness, strength and wear resistance characteristic of this alloy at both room and elevated temperatures. To this end the amounts of vanadium and molybdenum when either or both are present are controlled so that the relationship 0.8≦w/o V+0.5 (w/o Mo)≦9.0 is satisfied. Excessive amounts of either or both of vanadium and molybdenum adversely affect the hot workability of the alloy, promote the formation of undesirable ferrite, and, at elevated temperatures promote the formation of undesirable secondary phases such as sigma and/or chi phase. Accordingly, vanadium is limited to no more than about 4.0 w/o better yet to about 3.5 w/o max., and preferably to about 3.0 w/o max. Preferably, at least about 0.5%, better yet at least about 0.75% vanadium is present. For best results about 1.0-2.5% vanadium should be present. While up to about 10.0 w/o molybdenum can be present, it is better to limit molybdenum to no more than about 8.0 w/o. Best results are attained when the amount of molybdenum present is less than about 0.5 w/o. The sum of w/o V+0.5 (w/o Mo) is advantageously limited to about 1.0-6.0
Within the stated ranges for the alloy according to this invention, tungsten can be substituted for up to one-half of the w/o Mo in excess of 1.0 w/o in the ratio 2 w/o W:1 w/o Mo. When present, tungsten is limited to no more than about 8.0 w/o and better yet to about 6.0 w/o max. because excessive amounts of tungsten promote the formation of undesirable sigma phase and needlessly increase the cost of the alloy. When tungsten is present in the alloy, the amounts of vanadium, molybdenum and tungsten are controlled so that the relationship 0.8≦w/o V+0.5 (w/o Mo)+0.25 (w/o W)≦9.0 is satisfied. Preferably, the sum w/o V+0.5 (w/o Mo)+0.25 (w/o W) is limited to about 1.0-6.0. When less than about 1.0 w/o molybdenum is present in the alloy, tungsten is limited to no more than about 0.5 w/o max., preferably to no more than about 0.2 w/o max.
Carbon and nitrogen are present in this alloy to provide the desired hardness and strength through solid solution strengthening and by combining with chromium, vanadium and molybdenum to form carbides, nitrides and carbonitrides during heat treatment. These hard phases benefit the high temperature strength and the wear resistance of the alloy. Accordingly, up to about 1.50 w/o, preferably up to about 0.90 w/o, carbon can be present for cast products, whereas a maximum of about 0.80 w/o, preferably about 0.70 w/o max. carbon should be observed for wrought products to avoid excessive loss in hot workability. Preferably, a minimum of about 0.35 w/o, better yet at least about 0.40 w/o, carbon is present in the alloy. For best results, at least about 0.45 w/o carbon should be present.
While up to about 1.0 w/o nitrogen can be present in this alloy when made with powder metallurgy processes, cast or wrought forms can contain nitrogen up to its solubility limit but not more than about 0.85 w/o, better yet not more than about 0.75 w/o to avoid excessive loss in hot workability. For best results nitrogen is limited to no more than 0.65 w/o. At least about 0.25 w/o, preferably at least about 0.35 w/o, nitrogen is present in the alloy to provide good elevated temperature stress rupture ductility and the high elevated temperature strength and ductility which are characteristic of the alloy. For best results at least about 0.45 w/o nitrogen should be present. Carbon and nitrogen can substitute for each other as interstitial solid solution strengthening agents. Additionally, carbon and nitrogen can substitute for each other in the formation of hard phase precipitates such as Cr 23 (C,N) 6 , Mo 2 (C,N), and V(C,N). The desired properties previously described are readily provided by the present alloy when the sum (w/o C+w/o N) is at least about 0.7, and preferably at least about 0.8.
In order to obtain the best properties carbon, nitrogen, vanadium and molybdenum, and tungsten when present, are critically balanced in this alloy. Thus, for best results, the alloy should be balanced in accordance with the following relationship:
(1) (w/o C+w/o N)≧[0.65+0.15 (w/o V)+0.04 (w/o Mo+0.5 (w/o W))](1)
(2) (w/o C+w/o N)≦[0.65+0.38 (w/o V)+0.08 (w/o Mo+0.5 (w/o W))](2)
The alloy of the present invention is preferably fully austenitic at room and elevated temperatures in the solution treated and age hardened condition. A small amount of ferrite, however, can be tolerated which does not objectionably impair the hot workability of the alloy and/or the desired properties, for example, wear resistance, for a given application. In this regard ferrite is limited to no more than about 5 v/o (volume percent), better yet to not more than about 1 v/o max.
Nickel is important in the alloy because it promotes the formation of austenite. To this end at least about 3.0 w/o, better yet at least about 4.5 w/o, and preferably at least about 5.0 w/o nickel is present. A fully austenitic microstructure is assured with at least about 6.0 w/o nickel present. Nickel is limited to about 10.0 w/o max., preferably up to about 8.5 w/o max., because excessive nickel adversely affects the sulfidation resistance of the alloy.
A minimum of about 3.0 w/o, better yet at least about 4.0 w/o., and preferably at least about 4.5 w/o manganese is present in the alloy because it contributes to increased solubility of nitrogen in the matrix. Too much manganese adversely affects the oxidation resistance of the alloy and needlessly increases the cost of the alloy without providing any additional benefit. Accordingly, manganese is limited to a maximum of about 10.0 w/o, better yet to about 8.5 w/o max., and preferably to about 8.0 w/o max. For best results manganese is kept within the range 5.0-7.5 w/o.
Manganese can be substituted for nickel as an austenite stabilizer within the aforesaid ranges. Accordingly, the sum of the weight percents of manganese and nickel in the alloy is about 6.0-16.0 w/o, and preferably about 10.00-15.00 w/o.
A minimum of about 18 w/o, better yet at least about 19.0 w/o, and preferably at least about 20.0 w/o, chromium is present in the alloy to provide good resistance to oxidation and hot corrosion. Chromium is beneficial to the hot hardness of the alloy because it provides solid solution strengthening. It also combines with carbon and/or nitrogen as discussed hereinabove, to form chromium carbides and nitrides which are beneficial to the wear resistance of the alloy. Chromium is limited to a maximum of about 28 w/o, better yet to no more than about 25.0 w/o, and preferably to about 24.0 w/o max., because it promotes formation of undesirable ferrite and secondary phases, such as sigma phase. Best results are provided with chromium in the range 21.0-23.5 w/o.
Up to about 2.0 w/o max. silicon can be present in this alloy when prepared as cast product. However, for the wrought product silicon is limited to about 0.75 w/o max. When present silicon improves the retention of oxide scale on in-service parts fabricated from the present alloy. Preferably silicon is limited to no more than about 0.50 w/o max. for good resistance to hot corrosion in environments containing lead oxide.
A small but effective amount of boron, up to about 0.03 w/o, better yet up to about 0.02 w/o, is present in this alloy. When present, this small amount of boron is believed to prevent the precipitation of undesirable phases in the grain boundaries and also to improve stress rupture life and ductility. For best results about 0.001-0.015 w/o boron is preferred.
Other elements may be present in the alloy as incidental amounts or as residuals as a result of the melting practice utilized. In this regard up to about 0.05 w/o max. aluminum, up to about 0.01 w/o max. calcium, and up to about 0.01 w/o max. magnesium can be present as residuals from deoxidizing and/or desulfurizing additions. Niobium is limited to about 1.0 w/o max., better yet to no more than about 0.85 w/o, and preferably to about 0.2 w/o max., because it adversely affects the aging response and hot hardness of the alloy. Varying amounts of titanium and/or zirconium may also be present in stoichiomeric proportions as additional carbide, nitride and carbonitride forming elements.
The balance of the alloy according to the present invention is iron except for the usual impurities found in commercial grades of alloys provided for the intended service or use. However, the levels of such impurity elements must be controlled so as not to adversely affect the desired properties of the present alloy. In this regard phosphorus is limited to about 0.10 w/o max., preferably to about 0.05 w/o max. sulfur is limited to about 0.05 w/o max., preferably to about 0.015 w/o max.
The alloy of this invention can be prepared using conventional practices. The preferred commercial practice is to prepare a heat using the electric arc furnace and refine it using the known argon-oxygen decarburization practice (AOD). When additional refining is desired the heat is cast into the form of electrodes. The electrodes are remelted in an electroslag remelting (ESR) furnace and recast into ingots. The alloy is readily hot worked from a furnace temperature of about 2000°-2250° F. and air cooled. Articles and parts are readily fabricated from the alloy by such hot working techniques as hot extrusion, hot coining, hot forging and others from a furnace temperature of about 2050°-2150° F.
The alloy of the present invention is useful in a wide variety of applications, for example, automotive applications, including, but not limited to, exhaust valves, combustion chamber parts, shields for exhaust system oxygen sensors, and other parts exposed to elevated temperature corrosive environments. It is contemplated that the alloy could be utilized in other applications where high temperature, oxidizing and/or corrosive environments are encountered, for example, gas turbine and jet engine applications such as buckets and chambers. The present alloy is also suitable for use in a variety of forms such as bars, billets, wire, strip, and sheet.
The alloy is preferably solution treated prior to hardening. Solution treatment is carried out at a temperature low enough to avoid excessive grain growth, but sufficiently high to dissolve secondary carbides, i.e., those carbides, nitrides and carbonitrides for example, formed during the hot working operation and the cooling immediately subsequent thereto. Solution treatment is preferably carried out at about 2150°-2250° F. for about 1 hour followed by quenching to room temperature in air or water. Preferably the formation of coarse carbide and/or nitride precipitates during cooling is prevented by rapid quenching. Precipitation strengthening (i.e. age hardening) of an article formed from the alloy is preferably carried out by heating to about 1200°-1500° F. for about 4-8 hours, followed by cooling in air to room temperature. It is contemplated that an article formed from the present alloy can be aged while in service when used in a high temperature application such as internal combustion engines, where the operating temperature is substantially within the temperature range 1000°-1500° F. Parts can be readily finish machined in the precipitation strengthened condition.
For purposes of illustration 15 small experimental heats of the alloy of the present invention and a small heat of the 23-8N alloy were vacuum induction melted with the final additions of nitrogen and manganese being made under an inert atmosphere. The heats were cast into 2.75 in square ingots, homogenized at 2150° F. for 16 hours, and then stabilized at 2050° F. Thereafter, the ingots were forged into 1.125 in square and 0.75 in square bars. The compositions of the heats are set forth in Table I.
TABLE I__________________________________________________________________________Ex. C Mn Si P S Cr Ni Mo V B N__________________________________________________________________________1 0.39 5.91 0.27 0.025 0.006 22.00 7.50 0.20 1.20 0.004 0.552 0.52 6.20 0.29 0.023 0.005 22.15 7.50 0.20 1.24 0.004 0.423 0.51 6.11 0.26 0.016 0.007 22.39 7.48 0.21 1.39 0.005 0.544 0.69 6.05 0.28 0.026 0.005 21.98 7.48 0.21 1.62 0.004 0.585 0.38 6.17 0.29 0.028 0.005 22.10 7.55 0.20 1.71 0.004 0.556 0.52 6.10 0.29 0.025 0.005 22.05 7.54 0.20 1.79 0.004 0.507 0.69 5.94 0.28 0.026 0.005 22.07 7.43 0.19 2.31 0.004 0.568 0.52 7.11 0.30 0.026 0.006 21.95 7.58 0.20 2.35 0.004 0.569 0.68 6.82 0.29 0.022 0.006 22.14 7.49 0.20 2.77 0.004 0.5810 0.39 6.19 0.29 0.026 0.006 22.21 7.41 2.21 0.10 0.005 0.4011 0.54 5.89 0.30 0.029 0.005 22.12 7.46 4.46 0.10 0.004 0.4212 0.51 6.21 0.27 0.021 0.006 22.01 7.72 5.17 0.13 0.006 0.5313 0.68 5.90 0.29 0.028 0.005 22.11 7.54 6.41 0.15 0.004 0.4414 0.51 6.16 0.29 0.021 0.007 22.15 7.63 2.64 0.65 0.005 0.5215 0.52 5.91 0.28 0.020 0.006 22.24 7.44 2.43 0.12 <0.005 0.4823-8N 0.35 3.28 0.72 0.020 0.006 22.08 7.46 0.21 0.12 0.005 0.32__________________________________________________________________________ Exampe 15 includes 5.14% W. The balance of each composition was essentially iron.
Lengths of the 0.75 in square bars of each heat were solution treated as indicated in Table II and machined to rough dimension for standard A.S.T.M. subsize smooth bar tensile and stress rupture specimens. The rough specimens were then age-hardened as indicated in Table II and then machined to finish size.
TABLE II*______________________________________Ex. Sol. Temp (°F.) Aging Temp. (°F.)______________________________________1 2250 14502 2250 13503 2170 14004 2250 13005 2170 13006 2250 13507 2250 13008 2250 13509 2250 130010 2170 150011 2225 140012 2170 140013 2225 150014 2170 150015 2170 150023-8N 2170 1500______________________________________ *In all cases solution (Sol.) treatment was carried out for 1 hour followed by water quenching. Aging was carried out for 8 hours followed b cooling in air. The particular solution treatments and aging heat treatments were selected on the basis of solution studies and aging studies.
Results of room temperature and 1200° F. tensile tests are shown in Table III, including the 0.2% offset yield strength (0.2% Y.S.) and ultimate tensile strength (U.T.S.), both in ksi, as well as the percent elongation (El. %) and the reduction in cross-sectional area (R.A. %).
TABLE III__________________________________________________________________________Room Temp. 1200° F. 0.2% 0.2%Ex. Y.S. U.T.S. El. % R.A. % Y.S. U.T.S. El. % R.A. %__________________________________________________________________________1 126.2 174.5 7.6 9.6 86.9 103.0 6.8 12.42 148.2 184.9 9.4 10.8 115.1 124.0 3.5 5.53 111.7 163.6 10.6 10.7 -- -- -- --4 153.7 184.0 8.7 13.6 120.9 129.3 3.4 7.65 138.6 178.5 19.4 22.2 105.3 118.7 7.8 19.96 149.8 182.7 7.2 6.6 118.3 125.4 3.4 5.77 157.8 184.6 4.7 7.3 120.1 129.4 4.2 8.88 147.1 180.0 6.8 6.5 111.5 120.0 3.4 5.99 156.2 185.1 6.3 8.7 124.5 131.7 4.3 8.510 97.3 141.9 11.6 11.5 57.4 91.5 16.4 21.111 121.0 179.9 8.5 13.1 77.9 108.0 13.6 26.812 117.5 174.4 6.8 7.0 -- -- -- --13 122.6 177.4 2.5 3.9 81.5 117.7 10.3 16.714 93.1 150.5 9.7 9.6 -- -- -- --15 95.7 151.7 9.4 9.3 -- -- -- --23-8N 93.6 151.3 24.8 25.3 -- -- -- --23-8N* 105.0 156.0 20.0 35.0 46.0 80.0 24.0 18.0__________________________________________________________________________ *Data presented in L. F. Jenkins et al., "The Development of a New Austenitic Stainless Steel Exhaust Valve Material", Soc. of Automotive Engrs. Tech. Paper Series; Paper No. 780245 (1978) for a nominal composition of 23-8N and shown here for comparison purposes.
Table III illustrates the high strength provided by the present alloy at both room and elevated temperatures and which at the elevated temperature of 1200° F. is significantly better than the 23-8N alloy.
Stress rupture testing was carried out on duplicate subsize smooth bar stress rupture specimens at 1300° F. by applying a constant load to generate an initial stress of 35 ksi. The results of the stress rupture tests are shown in Table IV as the average of duplicate tests, including time to failure (Rupt. Life) in hours (h), the percent elongation (% El.) and the reduction in cross-sectional area (% R.A.).
TABLE IV______________________________________ Rupt.Ex. Life (h) % El. % R.A.______________________________________1 273.3 4.1 3.62 624.0 2.6 0.8 (1)3 247.9 11.8 16.04 525.1 6.6 3.5 (2)5 273.9 10.4 16.76 626.1 3.3 0.0 (2)7 642.7 4.9 3.5 (3)8 401.9 4.7 4.7 (2)9 609.2 8.1 10.9 (2)10 343.7 36.3 43.7 (4)11 520.2 23.6 34.712 471.7 25.3 56.213 327.6 33.7 66.914 271.6 36.8 51.815 408.7 31.9 51.223-8N 151.0 6.7 7.6______________________________________ (1)One specimen broke at end; one specimen broke at punch mark. (2)Both specimens broke at end. (3)Both specimens broke at punch mark. (4)One specimen broke at end.
Table IV illustrates the good stress rupture life of the present alloy which is significantly better than the 23-8N alloy.
Hot hardness testing was performed on samples of heats 2-4, 6, 7, 9, 12, 14, 15 and a sample of the 23-8N heat all of which were solution treated and aged in accordance with Table II above. The hot hardness specimens each measured about 0.39 in rd.×0.195 in high and the surface of each specimen was polished to a 6 micron finish.
Hot hardness testing was performed using an Akashi Model AVK-HF hot hardness tester. Indentations were made using a 5 kg load, measured, and then converted to DPH hardness in accordance with the standard test procedures for the apparatus. For each specimen, up to six hardness measurements were made and recorded at room temperature, 1000° F., 1200° F., 1400° F., and 1500° F. Elevated temperature specimens were sttabilized for five minutes before hardnesses were measured.
The results of the hot hardness tests shown in Table V as Vickers hardness numbers (HV) are the lowest and the highest (low/high) for each specimen at each test temperature.
TABLE V______________________________________HVEx. R.T. 1000° F. 1200° F. 1400° F. 1500° F.______________________________________2 412/435 313/325 280/329 268/280 241/2493 396/423 274/293 251/268 221/244 208/2254 412/429 303/329 293/306 260/271 232/2416 407/423 303/317 293/313 268/280 232/2467 423/435 306/353 296/345 271/289 241/2519 412/435 321/336 303/321 274/313 241/25112 362/391 227/262 223/244 210/216 203/22714 345/362 216/227 195/216 193/206 165/18015 362* 249/268 229/241 208/223 201/22123-8N 332/362 199/212 190/197 168/183 156/175______________________________________ *One R.T. reading taken for Ex. 15.
Table V illustrates the high hardness and good heat resistance of the present alloy. It is noted that the room temperature and elevated temperature hardness of present alloy is as good to significantly better than the 23-8N alloy. The data of Table V is also indicative of the improved wear resistance of the alloy as described more fully hereinbelow.
Wear testing was performed at 800° F. on specimens of Examples 3, 12, 15 and a specimen of the 23-8N alloy. Ring specimens were machined from blanks cut from the solution treated bars and aged in accordance with the heat treatments specified in Table II. The wear test was carried out by mating a ring specimen for a given example against AISI type M2 high speed steel with a load of 100 lbs and rotating the ring specimen at 100 rpm for one hour at 800° F. The results of the wear tests are shown in Table VI as the mass of material lost (Mass Loss) in milligrams (mg). The mass loss of each specimen was determined by taking the difference between weighings made before and after testing. A smaller mass loss indicates better wear resistance.
TABLE VI______________________________________Ex. Mass Loss (mg)______________________________________ 3 4.3, 13.212 3.6, 4.315 0.4, 0.823-8N 9.7, 12.6______________________________________
Table VI illustrates the significantly better wear resistance of the present alloy overall in comparison with 23-8N although one of the weight loss values for Example 3 is higher.
It can be seen from the foregoing description and the accompanying examples, that the alloy according to the present invention provides a unique combination of room temperature and elevated temperature strength and excellent heat resistance well suited to a wide variety of uses. The alloy, because of its excellent elevated temperature wear resistance is especially advantageous for the fabrication of engine valves. The improved wear resistance of the alloy also makes it more economical to use than those alloys which must be hard faced to achieve comparable wear resistance.
The terms and expressions which have been employed are used as terms of description and not of limitation. There is no intention in the use of such terms and expression of excluding any equivalents of the features shown and described, or portions thereof. It is recognized, however, that various modifications are possible within the scope of the invention claimed.
|
A heat, corrosion and wear resistant austenitic steel and article made therefrom is disclosed containing in weight percent about
______________________________________
w/o______________________________________Carbon 0.35-1.50Manganese 3.0-10.0Silicon 2.0 max.Phosphorus 0.10 max.Sulfur 0.05 max.Chromium 18-28Nickel 3.0-10.0Molybdenum Up to 10.0Vanadium Up to 4.0Boron Up to 0.03Nitrogen 0.25 min.Tungsten Up to 8.0Niobium 1.0 max.______________________________________
the balance being essentially iron. To attain the unique combination of properties provided by the present alloy w/o C+w/o N must be at least about 0.7, w/o V+0.5 (w/o Mo)+0.25 (w/o W) must be about 0.8-9.0.
| 2
|
CROSS-REFERENCED TO RELATED APPLICATION
This application is a Divisional Application of U.S patent application Ser. No. 12/554,201, filed Sep. 4, 2009, which is a Continuation of National Stage entry of International Application PCT/JP2007/000218, filed Mar. 13, 2007, the disclosure of the prior applications being incorporated in their entirety by reference.
TECHNICAL FIELD
The present application relates to a multi-carrier communication apparatus in a multi-carrier communication system using a broad communication band.
BACKGROUND ART
In a multi-carrier communication using a plurality of carrier waves, a broad and stable frequency characteristic including a DC component is demanded for a transmitter/receiver. Additionally, the demand for a broad effective band and a narrow sub-carrier interval has been increasing in recent systems in order to implement a high data throughput. To meet such demands, a filter, an RF element, etc., which are included in a signal system, must be implemented at a stable frequency characteristic.
If measures for suppressing frequency distortion in a filter, etc. are taken, power consumption generally increases. Moreover, an element must be manufactured with a semiconductor process using SiGe, etc., of a high unit price in order to suppress 1/f noise in the vicinity of DC, leading to an increase in the cost of the system.
FIG. 1 illustrates a receiver for a multi-carrier communication according to conventional technology.
A carrier wave band reception signal that is received by an antenna 10 passes through a transmission/reception switch 11 , a carrier wave bandpass filter 12 , and a low noise amplifier 13 . Then, the frequency of the reception signal is converted by being multiplied in quadrature demodulators 14 - 1 and 14 - 2 by local carrier waves that are generated by adjusting the frequency of the output of a local oscillator 19 with a synthesizer 21 and are implemented as a 0° phase wave and a 90° phase wave with a phase shifter 22 . Moreover, the output of the local oscillator 19 is generated as a clock signal that is frequency-adjusted by a PLL (Phase Locked Loop) 20 , and given to AD converters 17 - 1 and 17 - 2 . The clock signal is used as a sampling signal in the AD converters 17 - 1 and 17 - 2 . As the frequency of the clock signal, a frequency double the band of a baseband signal is used. Thereafter, the signals pass through lowpass filters 15 - 1 and 15 - 2 , and baseband signals are extracted. Their relations are expressed with the following equations. Alphabets enclosed with parentheses respectively indicate a signal passing through a corresponding portion.
carrier wave band reception signal received by the antenna 10 (signal in a portion of (A))
[ mathematical expression 1 ] s ( t ) = ∑ n = 0 N - 1 [ a n cos { 2 π ( f c + n f 0 ) t } - b n sin { 2 π ( f c + n f 0 ) t } ]
where:
a n =A n cos θ n : InPhase component b n =A n sin θ n : QuadraturePhase component N: Number of: MultiCariier
local carrier waves generated by the synthesizer 21
[Mathematical Expression 2]
I-Branch Local Carrier Wave
( B )=cos(2 πf c t )
Q-Branch Local Carrier Wave
( C )=cos(2 πf c tπ/ 2)=sin(2 πf c t )
reception signals the frequency of which is converted by the quadrature demodulators 14 - 1 and 14 - 2
[Mathematical Expression 3]
(D) I-Branch Reception Signal
S I ( t ) = s ( t ) cos ( 2 π f c t ) = ∑ n = 0 N - 1 [ a n cos { 2 π ( f c + n f 0 ) t } cos ( 2 π f c t ) - b n sin { 2 π ( f c + n f 0 ) t } cos ( 2 π f c t ) ] = 1 2 ∑ n = 0 N - 1 [ a n cos ( 2 π nf 0 t ) - b n sin ( 2 π nf 0 t ) ] + 1 2 ∑ n = 0 N - 1 [ a n cos ( 4 π f c t + 2 π nf 0 t ) - b n sin ( 4 π f c t + 2 π nf 0 t ) ]
(E) Q-Branch Reception Signal
S
Q
(
t
)
=
s
(
t
)
{
-
sin
(
2
π
f
c
t
)
}
=
∑
n
=
0
N
-
1
[
a
n
cos
{
2
π
(
f
c
+
n
f
0
)
t
}
{
-
sin
(
2
π
f
c
t
)
}
-
b
n
sin
{
2
π
(
f
c
+
n
f
0
)
t
}
{
-
sin
(
2
π
f
c
t
)
}
]
=
1
2
∑
n
=
0
N
-
1
[
a
n
sin
(
2
π
nf
0
t
)
-
b
n
cos
(
2
π
nf
0
t
)
]
-
1
2
∑
n
=
0
N
-
1
[
a
n
sin
(
4
π
f
c
t
+
2
π
nf
0
t
)
-
b
n
cos
(
4
π
f
c
t
+
2
π
nf
0
t
)
]
baseband signals after passing through the lowpass filters 15 - 1 and 15 - 2
[Mathematical Expression 4]
(F) I-Branch Baseband Reception Signal
s ~ I ( t ) = 1 2 ∑ n = 0 N - 1 [ a n cos ( 2 π n f 0 t ) - b n sin ( 2 π n f 0 t ) ] = 1 2 ∑ n = 0 N - 1 [ A n cos ( 2 π n f 0 t + θ n ) ] ( 1 - 1 )
where:
a n =A n cos θ n
b n =A n sin θ n
(G) Q-Branch Baseband Reception Signal
s ~ Q ( t ) = 1 2 ∑ n = 0 N - 1 [ a n sin ( 2 π n f 0 t ) - b n cos ( 2 π n f 0 t ) ] = 1 2 ∑ n = 0 N - 1 [ A n sin ( 2 π n f 0 t + θ n ) ] ( 1 - 2 )
where:
a n =A n cos θ n
b n =A n sin θ n
The baseband signals converted from the multi-carrier signal pass through variable gain amplifiers 16 - 1 and 16 - 2 , are sampled by the AD converters 17 - 1 and 17 - 2 , and converted into information for respective sub-carriers by an FFT unit 18 . d( 0 ) to d(N−1):{d(n)=a n +jb n } at the right of FIG. 1 represent the reception signals of the respective sub-carriers. N is the number of sub-carriers used, and the similar to the size of the FFT.
FIG. 2 illustrates the spectrum of the multi-carrier communication reception signal received by the antenna 10 .
The sub-carriers are allocated at the frequency interval of fo[Hz], centering on the frequency of the carrier wave fc[Hz]. If N sub-carriers are used, the frequency band of the entire multi-carrier signal is Nfo[Hz] d( 0 ) to d(N−1) of FIG. 2 correspond to those of FIG. 1 , and represent the symbols of the respective sub-carriers. d( 0 ) and d(N−1) are unused sub-carriers called guard tones, and provided to prevent adjacent channels from being impeded. Here, the number of sub-carriers of the guard tones on both sides is two. However, guard tones the number of which is approximately two-tenth of the total number of sub-carriers are used in an actual system. For example, if there are 100 sub-carriers, the total of 20 sub-carriers are defined as being unused on both sides of the signal band.
In FIG. 2 , d( 2 ), d(N/2−1), d(N−3), etc. are known reference signals that are called pilot symbols and intended to detect synchronization. For the pilot symbols, a sub-carrier the frequency of which is the similar to the carrier wave frequency fc[Hz] is not used in normal cases. The reason is as follows: when being converted into a baseband signal, the carrier wave frequency fc becomes a DC component, on which 1/f noise is superimposed, an SNR therefore becomes small, and a signal error tends to occur despite the existence of a pilot symbol.
FIG. 3 illustrates the spectrum of the reception signal when a frequency characteristic exists in the receiver.
The example of FIG. 3 illustrates an influence exerted by 1/f noise existing in the vicinity of DC after the reception signal is frequency-converted into a baseband signal. The 1/F noise occurs in the quadrature demodulators 14 - 1 , 14 - 2 , etc. illustrated in FIG. 1 . Additionally, a frequency characteristic, or the like, which degrades the signal power, can possibly exist in the vicinity of a particular frequency. In the case illustrated in FIG. 3 , the symbols of d(N/2−1) and d(N/2+1) are degraded by the influence of the 1/f noise.
For data sub-carriers and the frequency selective fading of a transmission channel, there are effective measures such as a frequency interleaver, etc. With the frequency interleaver, not sub-carriers of a fixed frequency but sub-carriers of different frequencies are used when the data symbols of one sequence are respectively transmitted. However, for a synchronization detection method using a continuous pilot sub-carrier to which a particular frequency is allocated to transmit a pilot symbol, there are no effective measures although a high SNR is demanded for the pilot symbol. Also a scattered pilot sub-carrier, to which a temporally different frequency is allocated to transmit a pilot symbol, causes a similar problem if degradation is caused by a frequency characteristic in a range where the frequency of the pilot symbol changes.
SUMMARY
According to an aspect of the embodiments, a multi-carrier communication apparatus transmitting/receiving a signal including a plurality of sub-carriers includes
a local carrier wave generating unit for generating a local carrier wave for demodulation; an offset adding unit for adding to the local carrier wave a frequency offset of a constant multiple of a frequency interval of a sub-carrier; and an offset varying unit for cyclically varying the constant of the offset. In this apparatus, the signal is demodulated by using the local carrier wave to which the frequency offset is added.
The object and advantages of the invention will be realized and attained by means of the elements and combinations articularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 illustrates a receiver for a multi-carrier communication in conventional technology;
FIG. 2 illustrates the spectrum of a multi-carrier communication reception signal received by an antenna;
FIG. 3 illustrates the spectrum of a reception signal when a frequency characteristic exists in a communication device;
FIG. 4 is a first configuration example of a multi-carrier receiver according to an embodiment;
FIG. 5 illustrates a change in the spectrum of a reception signal, which is made by executing a process according to the embodiment; and
FIG. 6 is a second configuration example of the multi-carrier receiver according to the embodiment.
DESCRIPTION OF EMBODIMENTS
In an embodiment, the band of a baseband signal after being frequency-converted is shifted by cyclically varying the frequency of a local carrier wave used for down conversion performed in a mixer, etc. with an integer multiple of the frequency interval of a multi-carrier for each OFDM symbol, if an SNR is degraded by a particular frequency including DC (frequency 0 ) due to a circuit characteristic. By shifting the band, the frequency of a signal, which degrades the SNR, is converted to another frequency that does not degrade the SNR. As a result, the influence exerted by the degradation may be prevented from concentrating on a particular sub-carrier.
In a normal multi-carrier communication system, both ends of an allocated frequency band are not used as guard tones. For example, in the specifications of a WiMAX system, an effective band is 11.2 MHz×(841/1024)=9.19 MHz in the band of 11.2 MHz. In this case, an unused band of 995 KHz of 91 sub-carriers exists at both ends of the band.
Accordingly, it is not difficult in the system to add an offset of the maximum of the guard tone band to the frequency of a local carrier wave. However, adding the offset drifts the allocation of sub-carriers in the baseband. This drift is an integer multiple of the frequency interval of the multi-carrier. Therefore, in the embodiment, the drift is cancelled by correcting a sub-carrier index, and the signal is received as if it were received at a fixed local frequency.
FIG. 4 is a first configuration example of a multi-carrier receiver according to the embodiment.
In FIG. 4 , the same components as those of FIG. 1 are denoted with the same reference numerals, and their descriptions are omitted. This configuration is implemented by adding a divider 26 , a multiplier 27 and a counter 25 to the conventional receiver illustrated in FIG. 1 . In this configuration, the signal is multiplied by an integer multiple a (namely, an offset) of a sub-carrier frequency (the local carrier wave that is the output of the synthesizer 21 ) (the signal after being multiplied by the offset is a signal of (J)). Here, a is an offset control signal that cyclically vaires for each OFDM symbol, and may be obtained as the output of the counter 25 . For example, if an unused portion of 91 sub-carriers exists, the counter 25 executes, for example, a process for cyclically counting up the value of a from 0 to 91. Here, the output frequency Nfo (a signal of (H) in this figure) of a PLL 20 (cos(2πNf o t)) is used for the AD converters 17 - 1 and 17 - 2 . Namely, this is a doubled frequency of the central frequency of the signal band to the frequency at the end of the signal band, and is the same frequency (Nf o ) as the band of the entire signal band. In the meantime, this becomes a frequency (f o ) equivalent to the band width of one sub-carrier if it is divided by the number of sub-carriers N. Additionally, the frequency becomes an offset that shifts sub-carriers by the value of a (af o ). Accordingly, multiplying the output frequency of the PLL 20 by a/N generates a frequency offset (af o ) that shifts sub-carriers by the value of a. As a result, I=cos(2πaf o t) may be obtained, and the signal of (J) represented by a mathematical expression 7 may be obtained by being multiplied b y cos(2πf o t) of the synthesizer 21 .
FIGS. 5A and 5B illustrate a change in the spectrum of the reception signal, which is made by executing the above described process in the embodiment. In these figures, the horizontal and the vertical axes represent a frequency and an SNR, respectively. In FIGS. 5A and 5B , one guard tone is respectively provided for one sub-carrier at both sides of the signal band (portions of d( 0 ) and d(N−1)). Moreover, since the band is not shifted in FIG. 5A , 1/f noise is superimposed on the DC portion. Therefore, the SNR decreases (the portion where the device frequency characteristic drops), and one SNR of the pilot signal at d(N/2−1) decreases. In the embodiment, the baseband is shifted by shifting the frequency of a local carrier wave by af o (a=1 here) as illustrated in FIG. 5B . Therefore, the entire signal band moves by f o , and the SNR of the pilot signal at d(N/2−1) is not degraded any more. In the meantime, the portion of the signal degradation becomes closer to the sub-carrier signal at d(N/2+1) by the shift of the signal band. Therefore, the SNR of the signal at d(N/2+1) decreases, and is degraded. In the case of FIG. 5B , the pilot signal is prevented from being degraded if it is left unchanged. Actually, however, a pilot signal of a smaller SNR may newly occur due to the existence of the frequency characteristic in another portion in the state where the local carrier wave is shifted. Accordingly, in the embodiment, the amount of shift of the local carrier wave is sequentially varied, and the state where the local carrier wave is shifted, and the state where the local carrier wave is not shifted are cyclically repeated. In the case of FIG. 5B , a=1. Therefore, cyclically repeating the amount of shift means that the case where the amount of shift is 0, and the case where the amount of shift is f o are alternately repeated. Accordingly, the state where the local carrier wave is not shifted as illustrated in FIG. 5A and the pilot signal at d(N/2−1) is degraded, and the state where the local carrier wave is shifted by f o as illustrated in FIG. 5B are repeated. Relations of the signals are represented with the following equations. Alphabets enclosed with parentheses respectively represent a signal passing through a corresponding portion in a similar manner as in FIG. 1 .
the output of the PLL 20
[Mathematical Expression 5]
( H )=cos(2 πNf o t )
where:
N: number of multi-carriers f o : frequency interval of multi-carrier
the output of the divider 26
[Mathematical Expression 6]
( I )=cos(2 πaf o t )
where:
a={0, 1, 2, . . . (Max absolute value=number of Guard Tone)}: SubCarrier offset
the output of the multiplier 27
[Mathematical Expression 7]
(
J
)
=
cos
(
2
π
f
c
t
)
cos
(
2
π
a
f
0
t
)
-
sin
(
2
π
f
c
t
)
sin
(
2
π
a
f
0
t
)
=
cos
{
2
π
(
f
c
+
a
f
0
)
t
}
offset local carrier wave
[Mathematical Expression 8]
I-Branch Local Carrier Wave
( B )=cos {2π( f c +af 0 ) t}
Q-Branch Local Carrier Wave
( C )=cos {2π( f+af 0 ) t−π/ 2}=sin {2π( f+af 0 ) t}
reception signals the frequency of which is converted by the quadrature demodulators 14 - 1 and 14 - 2
[Mathematical Expression 9]
(D) I-Branch Reception Signal
S I ( t ) = s ( t ) cos { 2 π ( f c + a f 0 ) t } = ∑ n = 0 N - 1 [ a n cos { 2 π ( f c + n f 0 ) t } cos ( 2 π ( f c + a f 0 ) t } - b n sin { 2 π ( f c + n f 0 ) t } cos { 2 π ( f c + a f 0 ) t } ] = 1 2 ∑ n = 0 N - 1 [ a n cos { 2 π ( n - a ) f 0 t } - b n sin { 2 π ( n - a ) f 0 t } ] + 1 2 ∑ n = 0 N - 1 [ a n cos { 4 π f c t + 2 π ( n + a ) f 0 t } - b n sin ( 4 π f c t + 2 π ( n + a ) f 0 t ) ]
(E) Q-Branch Reception Signal
S
Q
(
t
)
=
s
(
t
)
{
-
sin
{
2
π
(
f
c
+
a
f
0
)
t
}
}
=
∑
n
=
0
N
-
1
[
a
n
cos
{
2
π
(
f
c
+
n
f
0
)
t
}
{
-
sin
{
2
π
(
f
c
+
a
f
0
)
t
}
}
-
b
n
sin
{
2
π
(
f
c
+
n
f
0
)
t
}
{
-
sin
{
2
π
(
f
c
+
a
f
0
)
t
}
}
]
=
1
2
∑
n
=
0
N
-
1
[
a
n
sin
{
2
π
(
n
-
a
)
f
0
t
}
-
b
n
cos
{
2
π
(
n
-
a
)
f
0
t
}
]
-
1
2
∑
n
=
0
N
-
1
[
a
n
sin
{
4
π
f
c
t
+
2
π
(
n
+
a
)
f
0
t
}
-
b
n
cos
{
4
π
f
c
t
+
2
π
(
n
+
a
)
f
0
t
}
]
baseband signals after passing through the lowpass filters 15 - 1 and 15 - 2
[Mathematical Expression 10]
(F) I-Branch Baseband Reception Signal
s ~ I ( t ) = 1 2 ∑ n = 0 N - 1 [ a n cos { 2 π ( n - a ) f 0 t } - b n sin { 2 π ( n - a ) f 0 t } ] = 1 2 ∑ n = 0 N - 1 [ A n cos ( 2 π ( n - a ) f 0 t + θ n ) ]
where:
a n =A n cos θ n
b n =A n sin θ n
(G) Q-Branch Baseband Reception Signal
s ~ Q ( t ) = 1 2 ∑ n = 0 N - 1 [ a n sin { 2 π ( n - a ) f 0 t } - b n cos { 2 π ( n - a ) f 0 t } ] = 1 2 ∑ n = 0 N - 1 [ A n sin ( 2 π ( n - a ) f 0 t + θ n ) ]
where:
a n =A n cos θ n
b n =A n sin θ n
In the example of FIG. 5 , the maximum value of the sub-carrier offset a is the number of guard tones 1 at one side. As a result, a cyclically takes the value of 0 to 1 to 0 to 1 . . . every OFDM symbol. The basband signals after passing through the lowpass filters 15 - 1 and 15 - 2 in the case of a=1 in FIG. 5 are represented with the following equations.
baseband signals after passing through the lowpass filters 15 - 1 and 15 - 2
[Mathematical Expression 11]
(F) I-Branch Baseband Reception Signal
s ~ I ( t ) = 1 2 ∑ n = 0 N - 1 [ a n cos { 2 π ( n - 1 ) f 0 t } - b n sin { 2 π ( n - 1 ) f 0 t } ] = 1 2 ∑ n = 0 N - 1 [ A n cos ( 2 π ( n - 1 ) f 0 t + θ n ) ] ( 2 - 1 )
where:
a n =A n cos θ n
b n =A n sin θ n
(G) Q-Branch Baseband Reception Signal
s
~
Q
(
t
)
=
1
2
∑
n
=
0
N
-
1
[
a
n
sin
{
2
π
(
n
-
1
)
f
0
t
}
-
b
n
cos
{
2
π
(
n
-
1
)
f
0
t
}
]
=
1
2
∑
n
=
0
N
-
1
[
A
n
sin
(
2
π
(
n
-
1
)
f
0
t
+
θ
n
)
]
(
2
-
2
)
where:
a n =A n cos θ n
b n =A n sin θ n
The equation 2-1 that represents the I-Branch baseband reception signal, and the equation 2-2 that represents the Q-Branch baseband reception signal respectively correspond to the equations 1-1 and 1-2 that represent the signals to which an offset is not added. Whether or not an offset exists is determined by whether the symbol information A n , θ n for each sub-carrier is extracted either as the frequency component of 2πnf o t or as the frequency component of 2π(n−1)f o t (a=1 here). This may be corrected by adding an offset of +1, namely, d(0+1)=d( 1 ) to d(N−1+1)=d(N) to the frequency component outputs d( 0 ) to d(N−1): {d(n)=a n +jb n } after being processed by the FFT unit. By adding the offset of +1, the frequency components start to be extracted not at d( 0 ) but at d( 1 ). However, since d( 0 ) is originally unused as a guard tone, it does not matter.
In the case of a=1 illustrated in FIG. 5 , the pilot sub-carrier {d(N/2−1)} influenced by SNR degradation before being processed is not influenced any longer, and the data sub-carrier {d(N/2+1)} is influenced by the degradation in turn. However, the influence of the SNR degradation is scattered with the effects of frequency interleaving and an error correction according to conventional technology.
FIG. 6 is a second configuration example of the multi-carrier receiver according to the embodiment.
In FIG. 6 , the same components as those of FIG. 4 are denoted with the same reference numerals, and their descriptions are omitted.
In the above described example of FIG. 4 , the output of the synthesizer 21 is multiplied by the output of the divider 26 in order to obtain an offset local carrier wave. There is also a method for adding an offset by controlling the output frequency itself of the synthesizer 21 . The configuration illustrated in FIG. 6 is implemented by removing the divider 26 and the multiplier 27 from the configuration of FIG. 4 , and by adding the input of the offset control signal a to the synthesizer 21 instead. Here, the value that the counter 25 gives to the synthesizer 21 is the similar to the above described value. The synthesizer 21 multiplies a by the bandwidth (interval) of a sub-carrier preset within the synthesizer 21 , and multiplies the local carrier wave by the offset. In this case, the offset local carrier wave represented below may be obtained as the output of the synthesizer 21 .
offset local carrier wave
[Mathematical Expression 12]
I-Branch Local Carrier Wave
( B )=cos {2π( f c +af 0 )t}
Q-Branch Local Carrier Wave
( C )=cos {2π( f c +af 0 ) t−π 2}=sin {2π( f c +af 0 ) t}
According to the above described embodiment, an influence of degradation caused by a frequency characteristic specific to a communication device on a pilot sub-carrier, the position of which may not be changed on a frequency axis, may be reduced with an offset cyclically added to a local carrier wave. At this time, the probability that the pilot sub-carrier allocated at a particular frequency is influenced by the degradation depends on the cycle of the offset added.
Accordingly, the SNR may be improved as follows as a communication system without using a special process such as SiGe, etc. while using an element having a frequency characteristic that consumes less power and has an un satisfactory frequency characteristic.
To which extent the SNR is improved according to the embodiment is described below.
As is known, a conventional relation between a frequency characteristic and the CNR n (Carrier to Noise Ratio) of each sub-carrier is given by the following equation.
[ mathematical expression 13 ] CNR n = CNR A × 1 1 + 1 / SNR f × N subchan ( N subchan - N pilot ) + N pilot × SNR ( 3 - 1 )
where
CNR A : CNR in total band SNR f : degradation ratio of frequency characteristic to pilot sub-carrier N subchan : repetitive number of sub-carriers into which pilot symbol is inserted N pilot : number of pilot sub-carriers per N subchan
The relation after the CNR is improved according to the embodiment is given by the following equation.
[ mathematical expression 14 ] CNR n = CNR A × 1 1 + 1 / ( SNR f / b ) × N subchan ( N subchan - N pilot ) + N pilot × ( SNR f / b )
where
b: repetitive cycle of L 0 frequency offset of a/N
Here, SNR f is one-bth. This results from the findings that the SNR is degraded only once among b offset changes in the repetitive cycle of the offset since degradation is not caused by shifting the frequency of a pilot signal.
The above described embodiment refers to the configurations where a frequency offset is added to a local carrier wave on the side of the receiver. However, a frequency offset may be directly added to a carrier wave of a transmission signal on the side of a transmitter, and the signal may be demodulated on the side of the receiver. In this case, a baseband signal after being demodulated is obtained with a frequency offset added. Therefore, the baseband signal is processed by being given an offset that cancels the offset on the transmission side to an extracted frequency component after being processed by the FFT unit. This method for canceling the offset may be the similar to the method described with reference to FIG. 5 .
According to aforementioned embodiments, a multi-carrier communication apparatus that receives a pilot signal with less errors is provided.
According to aforementioned embodiments, an SNR of a particular frequency component of an obtained baseband signal may be prevented from being constantly degraded by a frequency characteristic by adding an offset to a local carrier wave at the time of demodulation and by varying the offset, even if the SNR of the particular frequency component is degraded by the frequency characteristic of an element within a receiving device.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiment(s) has (have) been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
|
A local carrier wave output from a synthesizer to quadrature demodulators is multiplied by an offset that makes a frequency shift by an integer number of subcarriers in units of sub-carrier bands. The offset is set to a value obtained by multiplying the number sequentially counted up from 0 to the number of unused sub-carriers included in guard tones in a signal band by the bandwidth of a sub-carrier. By shifting the frequency of the local carrier wave at the time of quadrature demodulation with the offset, the SNR of a baseband signal is prevented from being constantly degraded by a frequency characteristic possessed by the circuit of a receiver in a particular sub-carrier signal. Especially, by preventing a pilot signal from being constantly degraded, the signal can be received with higher accuracy.
| 7
|
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
CROSS REFERENCE TO RELATED APPLICATION
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a system for the direct sequencing of polymers such as DNA and RNA by passing the polymer through a nanoscale pore and measuring a light signal modulated by the polymer.
[0002] Genetic information is encoded in a molecule of deoxyribonucleic acid (DNA) as a sequence of nucleotides: guanine, adenine, thymine, and cytosine. Discovering the sequence of these nucleotides in DNA and other similar molecules is a foundational technology in biological studies.
[0003] One promising method of sequencing is “nanopore sequencing” in which a single strand of DNA, forming half of the DNA helix, is passed through a nanoscale opening in a membrane between two reservoirs. This nanopore opening may, for example, be a protein channel held in a lipid bilayer. An electrical potential or other gradient (i.e. molar concentrations. thermal, etc.) may be applied across the reservoirs to produce an ion flow between the reservoirs pulling the strand of DNA through the nanopore. As the strand passes through the nanopore, it modulates the ion current through the nanopore as a function of the size of the nucleotide obstructing the nanopore. This alteration in the ion current may then be analyzed to determine the nucleotide sequence. An example system of nanopore sequencing is described in PCT patent WO/2008102120 entitled: “Lipid Bilayer Sensor System”, and in European patent 2695949 entitled: “Nucleic Acid-based Nano Pores or Transmembrane Channels and their Uses”, both hereby incorporated by reference.
[0004] The electrical signals produced by changes in ion current through a nanopore with different nucleotides are very small in amplitude and accordingly long sampling times are required to distinguish the signals from noise, resulting in a slowing down of the sequencing process. The ability to obtain required sampling times may not be available because of the high speed of motion of the DNA strand through the nanopore.
SUMMARY OF THE INVENTION
[0005] The present invention provides a sequencing apparatus using an optically active nanopore. The nanopore includes a semiconductor nanoscale structure near the pore opening exhibiting quantum confinement effects that are affected by the electrical field of the long chain molecule passing through. Field-induced changes in the band gap of the nanoscale structure, as different portions of the long chain molecule pass through the nanopore, cause the emission of light at different frequencies such as may be mapped to different structures of the long chain molecule.
[0006] More specifically, one embodiment the invention provides an apparatus for a measurement of biomolecules using a separator with a nanopore providing a passage through the separator, the nanopore incorporating a nanoscale semiconductor element proximate to the passage that is adapted to emit light with a frequency dependent on a charge of a portion of biomolecules passing through the nanopore. A reservoir system holds a fluid on opposite sides of the separator to provide a flow of biomolecules through the nanopore from one side of the separator to the other and a spectrometer receives emitted light from the nanoscale semiconductor element to measure frequency of that light as biomolecules flow through the nanopore. An electronic computer communicates with the spectrometer and executes a program to relate light frequency measured by the spectrometer to structure of the portion of the biomolecules thereby providing a sequencing of biomolecule structures as the biomolecules passes through the nanopore.
[0007] It is thus a feature of at least one embodiment of the invention to provide an improved (high-speed) sensing structure for sequencing biomolecules making use of local interaction between the biomolecule and a light-emitting quantum confinement structure.
[0008] The nanoscale semiconductor element may be a ring concentric with the nanopore and bounded by different materials on nanoscale dimensions to provide a structure exhibiting quantum confinement effects.
[0009] It is thus a feature of at least one embodiment of the invention to provide a “quantum ring” sensor that may maximize sensitivity of the quantum structure to the electrical field of a material within the ring.
[0010] The different materials bounding the ring may also be semiconducting materials potentially increasing the sensitivity of the detection mechanism.
[0011] It is thus a feature of at least one embodiment of the invention to provide a quantum structure that may be readily fabricated using integrated circuit techniques on semiconductor materials.
[0012] The nanoscale semiconductor element and different materials may be group III/V semiconductors but can also be group II/VI.
[0013] It is thus a feature of at least one embodiment of the invention to provide materials that may produce a light output more easily communicated from the nanopore to a measuring instrument.
[0014] The semiconductor may be selected from the group consisting of: gallium arsenide, aluminum gallium arsenide, and indium arsenide.
[0015] It is thus a feature of at least one embodiment of the invention to provide a nanoscale semiconducting structure employing well-characterized materials.
[0016] The apparatus may further include a light source for providing stimulating energy to the nanoscale semiconductor element to promote an emission of light from the nanoscale semiconductor element.
[0017] It is thus a feature of at least one embodiment of the invention to promote light emission by providing a source of stimulating energy that may be tailored to the hand gap of the nanoscale semiconductor element.
[0018] The separator may be a solid material substantially unbroken outside of the nanopore over an area contacting fluid of the reservoir structure.
[0019] It is thus a feature of at least one embodiment of the invention to eliminate the need for fragile lipid bilayers normally used as separators between reservoirs in favor of a substantially continuous and more robust solid-state separator.
[0020] The separator may be a membrane holding the nanopore and adhered to a substrate of different material, the substrate having an aperture aligned with the nanopore.
[0021] It is thus a feature of at least one embodiment of the invention to permit fabrication of separators with nanopores using techniques, such as a local droplet etching, which have limited working depth by attaching a thin membrane etched using these techniques to a thicker substrate while aligning an opening in the two.
[0022] The nanopore may be substantially circular or may be non-circular in cross-section, either sized to control an orientation of the biomolecule as it passes through the nanopore,
[0023] It is thus a feature of at least one embodiment of the invention to promote the sequencing of biomolecules by mechanically constraining the flow of biomolecules through the nanopore.
[0024] The invention also provides a method of manufacturing separators of the type that can isolate reservoirs of liquid across at least one optically active nanopore. In the method, a matrix material is fabricated on a sacrificial layer supported by a first substrate and subjected to local droplet etching in which metal droplets erode nanoscale holes through the matrix material to the sacrificial layer. A second substrate is then prepared with a plurality of apertures larger than the nanoscale holes, wherein the second substrate is thicker than the matrix material. The matrix material is then removed from the sacrificial layer and adhered to the second substrate so that at least one nanopore aligns with at least one aperture. The adhered matrix material and second substrate are then divided into multiple separator elements each including a continuous passage through a nanoscale hole and aperture.
[0025] It is thus a feature of at least one embodiment of the invention to provide a robust separator that can eliminate the need for bilayer lipid membranes and yet still provide nanoscale holes.
[0026] The method may include separating the matrix material into a plurality of tiles after the local droplet etching and independently attaching the tiles to the second supporting substrate.
[0027] It is thus a feature of at least one embodiment of the invention to accommodate the random distribution of nanoscale holes obtained by techniques such as local droplet etching.
[0028] The matrix material may be adhered to the second substrate by van-der-Waals forces.
[0029] It is thus a feature of at least one embodiment of the invention to provide a method of attaching the matrix material to a supporting structure that permits a period of adjustment before permanently affixing the matrix material to the supporting structure.
[0030] The method may include the step of coating the nanoscale hole with a semiconductor material different from a material of the walls of the nanoscale hole.
[0031] It is thus a feature of at least one embodiment of the invention to permit the construction of a quantum confinement element proximate to a nanoscale opening for use in sequencing biomolecules and other similar applications.
[0032] These particular features and advantages may apply to only some embodiments falling within the claims and thus do not define the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a block diagram of a sequencing apparatus employing an optically active nanopore in exaggerated scale as positioned in a separator between reservoirs of fluid;
[0034] FIG. 2 is a detailed cross-section of the nanopore of FIG. 1 during fabrication, showing a semiconductor matrix material supported on a sacrificial layer attached to a construction substrate immediately after being etched by local droplet etching;
[0035] FIG. 3 is an expanded cross-section of the nanopore during use showing additional layers applied to the opening of the nanopore to create a quantum structure having conduction and valence bands providing a bandgap that varies with electrical interaction between the quantum structure and a proximal molecule being analyzed, and further showing in an inset, a spectrum of emitted light such as varies with such electrical interaction;
[0036] FIG. 4 is a simplified flowchart showing the formation of a separator of FIG. 1 by the attachment of nanopores in a matrix material to the supporting substrate; and
[0037] FIG. 5 is a top plan depiction of an elliptical and circular nanopore such as may be created with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0038] Referring now to FIG. 1 , an apparatus 10 for characterizing molecules passing through a nanopore may comprise a generally rigid planar separator 12 extending along a plane 15 and having an opening 14 passing through the separator 12 generally perpendicular to the plane 15 .
[0039] A reservoir structure having first and second reservoirs 16 a and 16 b may be constructed on either side of the separator 12 about the opening 14 to be separated from each other by the separator 12 and communicating only through the opening 14 . These reservoirs 16 a and 16 b may be filled with a conductive fluid 20 such as a buffer solution, for example, KCl solution, as held by capillary attraction or a fluidic channel. Reservoir 16 a may have an introduced source of biomolecules 22 (for example, single DNA strands or double strand DNA helices and the necessary proteins and enzymes to separate the helix into strands) suspended therein.
[0040] Each of the reservoirs 16 a and 16 b may hold electrodes 23 (for example, silver/silver chloride electrodes) communicating between with the liquid of the reservoir structure and a voltage source 24 together to provide an electrical voltage across the opening 14 tending to produce an ionic flow from reservoir 16 a to reservoir 16 b. This flow may draw the biomolecules 22 along with it causing individual biomolecules 22 to thread through the opening 14 . As monomers 25 of the biomolecules 22 pass through the opening 14 , different electrical charges associated with each monomer 25 may influence a quantum structure 27 proximate to the opening 14 .
[0041] In particular, during the flow of the biomolecules 22 , the quantum structure 27 may be excited with a light beam 28 , for example, from ultraviolet light source 30 focusing a beam of ultraviolet light on the quantum structure 27 , for example, through microscope objective 32 . In response to this excitation, the quantum structure 27 will emit light 34 which may pass upward through the microscope objective 32 along the path of the light beam 28 and then be separated by a beam splitter 36 from the light beam 28 and then directed toward a spectrometer 38 . As will be discussed below, the frequency of this emitted light 34 will be affected by electrical charges associated with different monomers 25 of the biomolecules 22 as they pass through the nanopore 26 generating a unique fingerprint for each monomer 25 related to the light frequency.
[0042] The spectrometer 38 receiving the frequency modulated emitted light 34 provides a frequency output 40 indicating a center frequency of the emitted light 34 . This frequency output 40 is then received by an electronic computer 42 for analysis. As is generally understood in the art, the electronic computer 42 may include one or more processing elements 44 communicating with a memory 46 holding a stored program executable on the processing elements 44 to analyze the frequency output 40 . The computer 42 may also control the light source 30 both to turn it on and off and optionally to adjust its intensity and/or frequency to improve the signal-to-noise ratio of the measured emitted light 34 .
[0043] The computer 42 executing a stored program will in turn provide sequence information 48 , for example, presented on an electronic display 50 or the like, providing a time sequence 52 of measurements indicating the sequence of monomers 25 in the biomolecules 22 as a function of time thereby sequencing the biomolecules 22 . In the case of a DNA biomolecule 22 , the monomers 25 will be guanine, adenine, thymine and cytosine whose different electrical fields provide different frequency modulation of the emitted light 34 .
[0044] In one embodiment, the separator 12 holding the nanopore 26 through which the biomolecules 22 pass, may be a laminated structure, for example, including a tile 54 of a semiconductor matrix material 55 holding the actual nanopore 26 supported on a support substrate 56 having a larger aperture 60 having diameters from 1 to 10 micrometers.
[0045] The tile 54 of semiconductor matrix material 55 may be of relatively small area, for example, several tens of microns on each side of a square perimeter and may have a thickness between 20 and 400 nanometers. Tile 54 will be relatively flexible and in some manufacturing processes may include multiple nanopores 26 and for this reason is supported on the upper face of the larger support substrate 56 , for example, the latter constructed of borosilicate glass quartz of much greater thickness (measured perpendicularly to plane 15 ), for example, in a range from 0.1 millimeters to 1.2 millimeters or more.
[0046] As noted, the nanopore 26 will be aligned with the larger aperture 60 in the support substrate 56 , the latter such as may be fabricated using a laser according the technique described in U.S. Pat. No. 8,092,739 “Retro-Percussive Technique For Creating Nanoscale Holes” and U.S. Pat. No. 8,623,496 “Laser Drilling Technique for Creating Nanoscale Holes” assigned to the assignee of the present invention and hereby incorporated by reference. In this technique, an ultraviolet absorbent liquid is confined to the back-side of a quartz substrate to absorb energy when pulsed by an excimer laser passing through the substrate.
[0047] Referring now to FIG. 2 , the nanopore 26 may be formed in the matrix material 55 by means of local droplet etching (LDE) of the type described in “Local droplet etching of nanoholes and rings on GaAs and Al GaAs surfaces”, A. Steinmann, Ch. Heyn, T. Köppenl, T. Kipp and W. Hansen Appl. Phys. Lett. 93, 123108 (2008) and “Scaling of the structural characteristics of nanoholes created by local droplet etching”, Ch. Heyn, S. Schnüll and W. Hansen, J. Appl. Phys. 115, 024309 (2014), hereby incorporated by reference,
[0048] In this process, the matrix material 55 , for example, an aluminum gallium arsenide semiconductor, may be fabricated on a sacrificial layer 62 , for example, of silicon dioxide or aluminum arsenide, this sacrificial layer 62 in turn supported by a much thicker and substantially rigid fabrication substrate 64 , for example, a silicon wafer. Sacrificial layer 62 is selectively removable by a solvent such as hydrofluoric acid so as to permit release of the matrix material 55 from the fabrication substrate 64 without damage to the matrix material 55 ,
[0049] While the matrix material 55 is held on the fabrication substrate 64 by the sacrificial layer 62 , metal droplets 66 are then formed on its surface through a nucleation process described in the above-cited references. In one embodiment these metal droplets 66 may be gallium or indium. During a post-growth thermal annealing step, the droplets 66 create nanopits 67 into the matrix material 55 . While the inventors do not wish to be bound by a particular theory, it is believed that the central process for this etching is a diffusion of arsenic from the matrix material 55 into the metal droplet and subsequent droplet material removal.
[0050] The resulting nanopit 67 extends through the matrix material 55 into the sacrificial layer 62 and becomes a nanopore 26 when the sacrificial layer 62 is removed. When the droplet 66 is gallium on an aluminum gallium arsenide matrix material 55 , the inner walls 68 of the nanopore 26 will be predominantly gallium arsenide in contrast to the aluminum gallium arsenide of the matrix material 55 . When the droplet 66 is indium, the material of the inner walls 68 will be indium arsenide. This technique may also be used with a gallium arsenide matrix material 55 in which ease the material of the inner wall 68 may be gallium arsenide with a different material property than the matrix material 55 caused by higher amounts of gallium, or indium arsenide,
[0051] The average diameter of the nanopore 26 will be less than 1000 nanometers.
[0052] Referring now to FIG. 3 , this inner wall 68 may be covered with a coating 70 of aluminum gallium arsenide (in the case of an aluminum gallium arsenide matrix material 55 ) to sandwich the inner wall 68 between two dissimilar semiconducting materials of aluminum gallium arsenide. The thickness of the inner wall 68 measured in the plane 15 may be less than 10 nanometers to provide quantum structure 27 having quantum confinement effects as will be discussed and as are caused by the confining effects of the coating 70 and material of the matrix material 55 , In addition a capping layer 72 , for example, gallium arsenide may be placed over the coating 70 . Generally gallium arsenide is compatible with DNA and thus a suitable capping material for capping layer 72 ; however, other materials may be used to provide a nonreactive outer surface with different biomolecules 22 .
[0053] The semiconductor materials of matrix material 55 , inner walls 68 , and coating 70 including capping layer 72 create a set of adjacent conduction bands 74 and valence bands 76 of different energies that produce a quantum confinement in the inner walls 68 as bounded by inner walls 68 and capping layer 72 as is necessary for optical emissions. This bounding of the inner wall 68 provides quantum structure 27 .
[0054] Generally the semiconductor materials may be selected from group MN or group however other material such as strained silicon germanium may be used. The group MN materials may be selected from gallium arsenide, aluminum gallium arsenide, and indium arsenide.
[0055] A bandgap 78 between the conduction bands 74 and valence band 76 of the inner walls 68 define a bandgap energy which determines the frequency of light emitted from the inner wall 68 when electrons drop between the conduction bands 74 and valence band 76 . The value of this bandgap energy separating the valence and conduction bands 76 and 74 of the inner wall 68 will change slightly in response to the electric field 80 associated with monomers 25 of the biomolecule 22 proximate to the inner walls 68 . The result will be a change in the frequency 82 of emitted light 34 depending on the monomer 25 .
[0056] This change in emitted light frequency 82 is detected by the spectrometer 38 shown in FIG. 1 and a measurement of center frequency transmitted to the computer 42 . A program running on the computer 42 may employ a predetermined a set of frequency zones 84 which are empirically determined and then used in mapping frequency of emitted light 34 to different zones 84 associated with different monomers 25 . Accordingly, movement of the frequency 82 of the emitted light 34 among the zones 84 provides a characterization of the monomers 25 and hence a sequencing of the biomolecule 22 as it passes through the nanopore 26 .
[0057] Referring now to FIG. 4 , fabrication of the separators 12 is complicated by the largely random process of nucleation used in local droplet etching. Accordingly the present invention, in one embodiment, controls the local droplet etching to reduce the density of holes produced to be, for example, an average one nanopore 26 for every tile 54 (for example, one nanopore 26 for every 10 to 100 micrometer square). As will be discussed below, multiple nanopores 26 may be accommodated on an individual tile 54 . Separation of the matrix material 55 into the tiles for may be accomplished by defining on the matrix material 55 a grid using optical lithography to provide an etch mask for a dry etch along boundaries between the tiles 54 . Finally a selective wet edge step may be carried out so that the tiles 54 released float off the carrier surface.
[0058] The support substrate 56 is then prepared with the regular spacing of larger apertures 60 and the separated tiles 54 placed on the support substrate 56 so that the nanopores 26 align with larger apertures 60 with the tiles 54 . Adjustment of the tiles 54 on the support substrate 56 may be accomplished while the tiles 54 are wet and may float on a liquid layer held by capillary force between the tile 54 and the support substrate 56 . Once properly located, the tile 54 is firmly attached to the support substrate 56 by van-der-Waals forces, which come into play when the liquid layer between the tile 54 and the support substrate 56 evaporates.
[0059] Alternatively dry tiles 54 may be placed directly on the support substrate 56 with suction enabled micro-pipettes 63 aligning the dry tiles 54 with the larger apertures 60 per arrows 61 .
[0060] The support substrate 56 may then be cut into the final dimension of the separators 12 as described above, each separator 12 holding one tile 54 and providing one functioning nanopore 26 . It will be appreciated that each tile 54 may have multiple nanopores 26 and that the alignment of a single nanopore 26 with a single larger aperture 60 may serve to limit the number of channels passing through each separator 12 .
[0061] In one embodiment, the WE etched matrix material 55 may be bonded directly to the support substrate 56 without being separated into tiles 54 with the expectation that the randomly located nanopores 26 will randomly align with some of the larger apertures 60 . These locations of alignment may then be determined, for example, by observation using photoluminescence measurements or the like and used to guide the division of the matrix material 55 and support substrate 56 into the separators 12 .
[0062] It is contemplated that in some embodiments, separators 12 with multiple nanopores 26 aligned with larger aperture 60 may be provided to be used for parallel sequencing operations where multiple biomolecules 22 are sequenced in parallel using separate light collectors and separate spectrographic analysis.
[0063] Referring now to FIG. 5 , it will be appreciated that the nanopore 26 may have a circular opening 94 (seen along the viewing axis normal to the plane 15 ) or by taking advantage of anisotropic characteristics of the semiconductor matrix material 55 , for example, crystal axis directions, which may have an ellipsoidal opening 96 . This latter shape may be desirable for sequencing of bio-molecules that are not circular in cross-section. For example, this opening 96 may be sized to roughly conform to a lateral extension of the monomers 25 in the plane 15 thereby provoking a rotation of the biomolecule 22 as it passes through the nanopore 26 such as may assist in controlling the progression of the biomolecule 22 through the nanopore 26 Or to select among different biomolecules, Alternatively this orientation may assist in providing more standardized effects of the electrostatic field of the monomers 25 On the surrounding quantum structure 27 formed from inner wall 68 .
[0064] In this document, “different materials” refers to materials having different band energies and includes materials with different doping concentrations such as may be suitable for creating a quantum confinement structure.
[0065] Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference, which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and Words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context.
[0066] When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
[0067] References to a “processor” or “processor unit” should generally be understood to refer broadly to general-purpose computer processing elements for executing stored programs (software) comprised of sequences of arithmetic and logical operations stored in the general-purpose memory. The term “circuit” as used herein should be considered to broadly include both analog and digital circuitry together with associated firmware. The term “program” generally refers to a sequence of operations executed by a processor or circuit. References to memory, unless otherwise specified, can combinations of different memory structures including solid-state and electromechanical memories and may describe a distributed system of main memory and multiple cache layers.
[0068] It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties.
|
A nanoscale-sized pore positioned between two reservoirs may sequence biomolecules by detecting changes in the emitted light due to a change in charge of portions of the biomolecules as they pass through the pore such as affect an emission frequency of a quantum structure proximate to the pore opening. The nanopores may be fabricated using local droplet etching whose randomness is accommodated by lowering the droplet density to permit isolation of nanopores in tiles that may be adhered to an underlying supporting substrate having an aligned opening. The nanopore-tiles may be integrated with commonly applied glass chips and may be employed in microfluidic circuitry.
| 1
|
BACKGROUND AND SUMMARY OF THE INVENTION
Coal, as mined, contains various forms of impurities including ash-forming minerals which form ash when combusted (hereinafter referred to as "ash-forming mineral matter") and inorganic (or pyritic) and organic sulfur. In order to make coal a more acceptable fuel, a significant proportion of the impurities must be removed. The conventional coal cleaning techniques, such as dense medium baths, cyclones, jigs and tables, can remove relatively coarse-grained impurities from coal without too much difficulty. However, the clean coal product from these techniques still contains a large amount of impurities typically in the 6-10% ash and 0.6-1.7% sulfur ranges. These impurities are finely disseminated in the coal matrix and, therefore require fine grinding before any separation technique can be applied to further remove them.
The objective of the grinding step is to liberate the mineral matter from the coal matrix. In some cases, the coal must be pulverized to micron sizes to achieve sufficient liberation. However, the micronizing is an energy-intensive process requiring sometimes 100 kwh or more of energy to pulverize a ton of coal. Furthermore, the size reduction frequently leads to a substantial fraction still containing "composite particles" made of both coal and mineral matter which are difficult to separate, resulting in a substantial loss of coal.
A micronized coal produced with such a large expenditure of energy is difficult to handle, and it is hard to clean it of its impurities. Many new fine coal cleaning processes have been suggested, including conventional froth flotation, microbubble flotation, selective agglomeration, selective flocculation, etc. Some of these techniques have been known to produce super-clean coal containing less than 1 or 2% ash and reduced sulfur. However, these processes suffer from relatively high consumption of reagents, difficulty in dewatering and generally low recovery, which are typical problems in processing fine particles. Chemical cleaning techniques oan produce super-clean coal from a relatively coarse coal, but it is intrinsically more expensive than the physical cleaning processes mentioned above.
The present invention suggests a new concept for cleaning coal of its mineral matter, including both the ash-forming minerals and pyritic sulfur. Meyers (U.S. Pat. No. 3,768,988) showed that pyritic sulfur can be removed substantially by treating the coal with ferric ions. In this process, the pyritic sulfur is oxidized at about 100° C. to elemental sulfur and sulfate by the ferric ions, while the ferric ions are reduced to ferrous ions. In the Meyers process, the ferric ions are regenerated from the spent ferrous ions by blowing air or oxygen at a relatively high temperature. In a similar process, Lalvani et al. (1983) showed that ferric ions can be regenerated by an electrochemical method. Both Meyers and Lalvani showed that a significant amount of pyritic sulfur is removed from the coal, but neither of these processes showed any ash-forming mineral matter removal.
SUMMARY OF INVENTION
In the present invention, a coal containing said impurities is exposed to ferric ions. To keep the ferric ions from precipitating as ferric hydroxide, an acidic condition, below approximately pH 2 or 3, is preferred. The ferric ions are reduced to ferrous ions on the coal surface, which in turn makes the coal surface slightly oxidized. Since the coal oxidation involves a loss of electrons from the coal, the surface is positively charged. It is well known that in acidic pH, most of the inorganic mineral matter is also positively charged. This creates a situation in which the ash-forming mineral matter is electrostatically repelled from the surface of the coal which helps dislodge the mineral particles from the coal surface and creates crevices or pores. If the pores are large enough, the ash-forming mineral matter dislodged as such migrates out of the coal due to electrostatic repulsion or due to the potential gradient.
If the opening of the pore is too small for the ash-forming mineral matter to migrate out, there will be a build-up of osmotic pressure inside the pore by the following mechanism. Inside the pore, the positively charged surfaces of both the coal and the ash-forming mineral matter attract counter ions such as sulfate or chloride that may be present in the system, establishing a diffuse electrical double layer. The coal becomes positively charged by the adsorption of protons and, more importantly, by the reaction of ferric ions with the sessile bonds of the coal molecule. This process results in a reduction of the chemical potential of the water inside the crevices and pores to below that of the water outside. This chemical potential difference forces the water molecules from the bulk solution into the crevices, thereby increasing the osmotic pressure. The pressure will continue to increase as long as the ferric ions react with the coal surface. Due to this pressure, the crevices of the pores of the coal open up, allowing the dislodged ash-forming mineral matter particles to migrate out of the coal matrix. Also, the breakage of the sessile bonds helps open up the pore structure. Thus, this process is essentially a liberation process induced by surface chemical reactions. An important feature of this system of ash-forming mineral matter liberation is the remarkably "sharp" separation of coal-free mineral matter particles and, thus, good recovery of clean coal in the overall process. Usually, the ash-forming mineral matter particles liberated as such from coal are of micron sizes and, therefore, can be removed by a simple screening process. Other physical cleaning processes, such as froth flotation, oil agglomeration etc., may also be used to remove the liberated mineral matter.
There are many different methods of regenerating ferric ions from the spent ferrous ions. In addition to the aforementioned aeration and electrochemical methods, micro-organisms such as Thiobacillus ferooxidans or chlorine may be used. In general, these processes are relatively inexpensive to operate and require a relatively small capital expenditure. Since a continuous supply of ferric ions is an important part of the process and since ferric ions can be regenerated cheaply, the liberation and separation process is economically attractive. A distinct advantage of this process is that the coal can be cleaned without the costly step of micronization. A relatively coarse coal, as large as 1/4 inch in diameter, can be cleaned by this process to 1% ash. However the finer the coal size to be treated by this process, the less time is required to obtain a desired ash level and the lower the final ash content.
Further, the invention contemplates the utilization of a novel coal reactor in which coal particles are loosely packed in a container having first and second ends, which are closed off by porous diaphragms. An inlet chamber, including a working electrode, a reference electrode, a counter electrode and a fluid inlet, communicates with the diaphragm of the first open end of the container. The fluid outlet from the diaphragm of the second open end of the coal container communicates with the fluid inlet of the first chamber. A potential is applied to the electrodes, and electrolyte is continuously circulated into the fluid inlet, through the loosely-packed coal bed, and out the fluid outlet.
It is the primary object of the present invention to significantly reduce the ash content of coal with relatively low energy consumption and high coal recoveries (high Btu recovery. This and other objects of the invention will become clear from an inspection of the detailed description of the invention and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating the steps in the practice of an exemplary method according to the present invention;
FIG. 2 is a schematic side view, partly in cross-section and partly in elevation, of an exemplary apparatus for effecting coal cleaning in an acidic medium and for regenerating ferric ions by an electrochemical method in the practice of the present invention;
FIG. 3 is a schematic side view, partly in cross-section and partly in elevation, of an alternative exemplary construction for effecting coal cleaning in an acidic medium and for regenerating ferric ions by an electrochemical method according to the present invention;
FIGS. 4 and 5 are graphical representations of variations of coal ash percentage with respect to other variables; and
FIG. 6 is a schematic side view like that of FIG. 3, only another embodiment of the reactor according to the invention.
DETAILED DESCRIPTION
FIG. 1 schematically illustrates an exemplary method of practicing the present invention. Feed coal, previously washed or unwashed, is fed to station 10 where it is crushed or pulverized by conventional techniques. After the size reduction, the coal is fed to a ferric ion treatment station (12), after which separation of the coal from the ash-forming mineral matter liberated during Ferric Ion Treatment is practiced (in step 14). In this step, sulfur and some of the mineral matter dissolved into solution from coal during the Ferric Ion Treatment are also removed. Additional organic sulfur treatment may take place in step 16. The coal resulting after the ash and dissolved sulfur removal (step 14) is the final clean coal product.
In the Ferric Ion Treatment stage (12), the coal particles are subjected to intimate contact with a mildly acidic medium. The exact conditions of the ferric ion treatment will depend upon the type of coal, the required ash content of the product coal and other factors. Effective process variables include coal type, particle size, contact time, temperature, type of electrolyte, applied potential, electrode material, and the concentration and relative composition of the ferrous/ferric couple.
The mechanism of the ash removal process, according to the present invention, is believed to occur as a result of the Donnan equilibrium of ions between the interior and the exterior of the pore structure of the coal. A Donnan potential is established when there is an unequal distribution of ions across a membrane or a charged surface. The coal surface is charged positively primarily by an electrochemical mechanism involving a surface oxidation of the coal coupled with a reduction of ferric ions to ferrous ions. The ferric ions can be obtained from the leaching of the pyrite in the coal in an acidic medium or added extraneously. Since the ferric ions are reduced to ferrous state during the process, the ferric ions should be continually replenished if the total iron concentration is small. The spent ferric ions can be regenerated by various methods, including the electrochemical technique. In this method, an inert electrode is placed in the coal slurry, and a potential is applied. The potential should be higher than the equilibrium potential of the ferrous/ferric couple. In addition to oxidizing the ferrous ions to ferric ions, the applied potential also serves to provide an oxidizing environment for the leaching of coal pyrite.
The mechanism of ash rejection by this process may be explained as follows. When the coal surface is superficially oxidized by the electrochemical mechanism described above, the coal surface becomes positively charged because it loses electrons to the ferric ions. It is believed that the oxidation occurs preferentially on the sessile bonds of the coal molecules, which may help to break up a part of the cross-linked coal structure and open up the pores. Since most of the ash-forming minerals are also positively charged in very acidic solutions, this charging process of the coal surface helps dislodge the ash-forming mineral matter particles from the coal surface. If the pore size is large enough, these ash-forming mineral matter particles will migrate out of the pores due to the potential gradient that exists between the interior of the pore and the bulk solution. However, when the opening of the pore is small, the ash-forming mineral matter particles cannot migrate out of the pores and, therefore, contribute to the build-up of positive charge inside the pore.
The positively-charged surfaces of coal and mineral matter cause negatively-charged ions (such as sulphate) to migrate inside the pore, setting up a Donnan potential gradient. The high concentration of ions present inside the pore reduces the chemical potential of the solvent (water) inside the pore below that of the bulk water outside the pore and forces the water molecules to migrate into the pore, creating an osmotic pressure. The pressure will continue to build up inside the pore as long as the ferric ions react with the coal surface according to the aforementioned mechanism. When the pressure is large enough, the pore structure will open up and allow the trapped mineral matter to migrate out of the coal matrix. Electron micrographs of the coal samples tested actually show the morphological changes in the processed coal. It is important to note that this process is essentially a mineral liberation process, and one can actually see the liberated ash-forming mineral matter mixed with coal particles. It is also noted here that although most of the mineral matter is removed physically by the mechanism described above, a small portion of it is removed by chemical dissolution since the process is carried out in an acidic media.
FIG. 2 illustrates one exemplary form of apparatus that may be utilized to practice the Ferric Ion Treatment step (12) of FIGURE I. The apparatus of FIG. 2 comprises a water-jacketted (the water jacket is not shown) stirred reaction vessel. The temperature of the cell is maintained constant by a circulating water bath through the water jacket. The vessel (20) has a top portion (24) thereof, and a working electrode (22) is inserted through a stopper (23) in the top (24) into a slurry within the vessel (20). The reference electrode (26), disposed in chamber 27, which communicates via a Luggin capillary (28) with the interior of the vessel (20), is also operatively associated with the top (24). The counter electrode (30), disposed in the counter electrode-containing chamber (31) with the porous diaphragm (32) (e.g., glass frit) at the open bottom thereof, also extends into the vessel (20). Enlarged electrode portions (34,35) are provided at the bottoms of the working electrode (22) and counter electrode (30), respectively. A thermometer (37) may also pass through a stopper (38) in the top of the vessel, into the interior of the vessel. The coal slurry in the vessel (20) is kept in suspension by a Teflon-coated magnetic stirring bar (40) which is designed so that its spinning action does not pulverize the coal. The reference electrode (26), which preferably is a calomel reference electrode, provides a reference against which potentials are measured. In this reactor, the coal particles make contact with the working electrode. A potential (e.g., about 1 V SCE (the potential must be greater than 0.5 V SCE)) is applied to the electrodes.
The reactor (41) of FIG. 3 is the preferred form of reactor for treating coarser coal particles. In this reactor, the coal particles do not contact the electrode surface but, rather, a continuous flow of electrolyte through the reactor takes place. This reactor includes a container (50) which has open first and second ends closed off by porous diaphragms 51 and 52, respectively. The container (50) has a loosely-packed bed of coal particles therein and, preferably, is surrounded by a water jacket (53) to maintain the temperature therein constant.
Operatively associated with the porous diaphragm (52) at the first end of the container (50) is the inlet chamber (54), which includes a fluid inlet (55), working electrode (57) having enlarged operative portion 58 thereof, and a reference electrode (59). Operatively associated with the second diaphragm (51) is the fluid outlet (62). The counter electrode (64) is associated with the inlet chamber (54) through a glass frit (61). A pump (70) continuously circulates electrolyte from the outlet (62) to the inlet (55), past the working electrode (57), and through the coal particles in the container (50). A potential is applied to the electrodes by any suitable source.
In this embodiment, ferric ions are constantly regenerated at the working electrode, flow through the coal bed, and are subsequently reduced to the ferrous state by reaction with the coal. The ferrous ions are pumped back to the electrochemical chamber, where they are converted to ferric ions, and the process continues. The reactor (41) will normally be used for cleaning relatively coarse coal so that the particle bed formed can be porous enough to pass the electrolyte.
The embodiment illustrated in FIG. 6 is very similar to that illustrated in FIG. 3 except for the location of the counter electrode with respect to the working electrode 57. The operation is also basically the same. In the FIG. 6 embodiment, like structures are illustrated by the same reference numeral as in the FIG. 3 embodiment, only preceeded by a "1".
The ash removal stage (14) according to the present invention may comprise any suitable conventional equipment for separating the ash-forming mineral matter particles from the coal particles. If the coal particles are of size 325 mesh or greater, ash-forming mineral matter removal is preferably accomplished by utilizing conventional wet screening techniques. Alternatively, a cyclone-type separator could be utilized, possibly in combination with a microbubble flotation apparatus. Other conventional separation techniques are also utilizable, such as the oil agglomeration, selective flocculation and conventional froth flotation techniques. Essentially, in all these proposed schemes, the aforementioned costly micronizing step is replaced by the Ferric Ion Treatment step according to the present invention.
The invention will now be described with respect to several examples:
EXAMPLE 1
A coal sample from Glamorgan Coal Company, assaying 1.65% ash-forming mineral matter and 0.6% sulfur, was tested in the stirred-tank reaction vessel (FIG. 2). The experiments were carried out using a 3.63 moles/l sulfuric acid solution at 65° C. A potential of 1.0 V SCE was applied between the platinum and the calomel reference electrodes to regenerate the ferric ions. The results, given in FIG. 4, show that the ash removal improves with decreasing particle size and that a product coal assaying less than 0.8% ash can be obtained from a relatively coarse coal. Further tests were conducted by increasing the reaction time to 13 hours using a coarse (-16+20 mesh) and a fine (-100+140 mesh) fraction. As shown in FIG. 5, the ash removal improves with increasing reaction time. The ash removal curve for the coarse coal flattens out after approximately 7 hours, while that for the fine coal continues to improve after 13 hours of treatment.
Table I shows the results obtained with Glamorgan coals of finer size fractions using a 3.63 moles/l sulfuric acid solution and a potential of 1.0 V SCE at 65° C. The -140+270 mesh coal had its ash content reduced from 1.25% to 0.4% after 4 hours of treatment. The -270+325 mesh coal had its ash content reduced from 1.23% to 0.32% after 10.5 hours of treatment. Coal recoveries (i.e., recoveries of combustible material) were very high in both instances.
TABLE I______________________________________Results of the Ferric Ion Treatment Tests Conducted onGlamorgan Seam Coal Reaction Power Ash (% wt) CoalSize Time Consumption Pro- Recovery(mesh) (hours) (kwh/ton)* Feed duct (% wt)______________________________________-140 + 270 4 1.8 1.25 0.40 98.26-270 + 325 10.5 3.83 1.23 0.32 97.49______________________________________ *for regenerating spent ferric ions
The effect of different electrolytes on the removal of ash-forming mineral matter have been studied on relatively coarse fractions of Glamorgan coal. As shown in Table II, the best results were obtained when using a combination of 90% sulfuric and 10% hydrofluoric acid solutions by volume, both of 3.63 moles/l. In addition to these reagents, ferric sulfate solution was added in the amount of 1% by weight of the feed coal. After 4 hours of treatment at 80° C., the ash content was reduced from 1.28% to 0.51% with 96.2% coal recovery.
TABLE II______________________________________Effect of Various Electrolyte Combinations on the Ferric IonTreatment of Glamorgan Coal Temper- Ash (% wt) CoalSize ature Pro- Recovery(mesh) Electrolyte (°C.) Feed duct (% wt)______________________________________ -7 + 12 H.sub.2 SO.sub.4 (3.63 M) 60 1.45 1.06 98.6-20 + 60 H.sub.2 SO.sub.4 + HCl 60 1.28 0.96 96.5-20 + 60 90% H.sub.2 SO.sub.4 + 60 1.28 0.73 96.0 10% HF-20 + 60 90% H.sub.2 SO.sub.4 + 60 1.28 0.57 96.8 10% HF + 1% FeSO.sub.4 *-20 + 60 90% H.sub.2 SO.sub.4 + 80 1.28 0.51 96.2 10% HF + 1% FeSO.sub.4 *______________________________________ *% weight of coal
EXAMPLE 2
A coal sample from the Widow Kennedy seam was obtained from Wellmore Coal Company, Virginia. The -20+40 mesh fraction of the coal, assaying 23.4% ash, was treated in 3.63 moles/l sulfuric acid solution while applying a potential of 1.0 V SCE at 65° C. The working electrode used in these experiments was graphite. Table III shows the results of the two sets of experiments. In one experiment, the coal was treated continuously for 15 hours. In another, the feed coal was treated in three consecutive stages of 5, 6 and 4 hours each, for a total of 15 hours. After each stage of treatment, the coal was placed on a 40 mesh screen and sprayed with water to remove the liberated mineral matter.
TABLE III______________________________________Effect of Staged Ferric Ion Treatment on Widow Kennedy CoalReaction CoalTime Ash (% wt) Recovery(hours) Feed Product (% wt)______________________________________15 23.4 8.5 95.535,6,4 23.4 3.5 94.64______________________________________
The results show that the continuous treatment reduced the ash content to 8.5%, while the intermittent treatement reduced it to 3.5%. This example shows that a multi-stage treatment is advantageous for producing a lower ash coal.
In another experiment, the -3+7 mesh fraction of the Widow Kennedy coal was cleaned of its mineral matter in a laboratory scale dense medium bath to obtain 5.3% ash. The cleaned coal was treated by the present invention using the flow-through type reactor (FIG. 3). The test was carried out in sulfuric acid solutions of 2.4 and 3.63 moles/l at ambient temperature. The reaction time was 7 hours, and a potential of 1.0 V SCE was applied on a platinum electrode to regenerate the spent ferric ions. The results, given in Table IV, show that the present invention can reduce the ash to a very low level in a relatively coarse coal.
TABLE IV______________________________________Results of the Ferric Ion Treatment of Low-Ash WidowKennedy Coal Using the Flow-Through Cell CoalSulfuric Acid Concentration Ash (% wt) Recovery(moles/l) Feed Product (% wt)______________________________________2.4 5.3 1.01 98.253.63 5.3 0.99 98.12______________________________________
EXAMPLE 3
In this example, a Powell Mountain coal, assaying 2.6% sulfur and 9% ash, was treated without adding any acid extraneously. The test was made in distilled water at 65° C. Ferric ions were regenerated using a graphite electrode at 1.0 V SCE. It appears that with a high sulfur coal, enough sulfuric acid and ferric ions are generated from the dissolution of the coal pyrite. The test was carried out in three successive stages with intermittent wet-screening after each stage to remove the liberated mineral matter. The filtrate from the previous test was re-used in the subsequent stages. The currents were very low in the first stage, indicating slow reaction rates. After each stage, however the currents increased, indicating an improved reaction rate due to an increased amount of ferric ions derived from the coal pyrite. The results, given in Table V, show that the ash content was reduced from 8.2% to 5.7%.
TABLE V______________________________________Results of the Cleaning of Powell Mountain Coal Ash Sulfur Volatile Matter (% wt) (% wt) (% wt) Btu/lb______________________________________Feed 8.2 2.6 39.4 13,670Product 5.7 2.0 41.3 14,010______________________________________
Although the ash removal was not as significant as in the foregoing examples, this example demonstrates that the ash rejection is possible without using acids. Another significance of this example is that the present invention does not reduce the volatile matter content of the coal during processing.
EXAMPLE 4
A coal sample (-20+40 mesh) from the Middle Wyodak seam, assaying 4.7% ash and 0.44% sulfur, was tested in this example. In one experiment, the coal was treated at 66° C. for 5 hours in a standard manner using 3.63 moles/l of sulfuric acid and a potential of 1.0 V SCE on a platinum electrode. The product coal assayed 1.5% ash. In another test, a fresh coal sample was treated using the filtrate obtained from the first test. After 5 hours of reaction time, the ash was reduced from 4.7% to 1.4%. These results suggest that, in continuous operation, the reagent consumption can be minimized by recirculating the spent electrolyte.
EXAMPLE 5
A coal sample (-60+150 mesh) from the Upper Wyodak seam, assaying 8.6% ash and having a calorific value of 9,189 Btu/lb, was tested in this example. The sample was treated first in a mixture of 5% (by weight) hydrochloric and 15% sulfuric acid solutions at 65° C. using a platinum electrode at 1.0 V SCE. After 7.5 hours of treatment, the coal was placed on a 150 mesh screen and washed of its liberated mineral matter. The washed coal, containing 5.2% ash and 11,390 Btu/lb, was treated again with fresh electrolyte for another 7.5 hours under identical conditions. The ash was further reduced to 2.3%, and the calorific value was increased to 11,700 Btu/lb. This is another example showing that a multi-stage treatment is beneficial in obtaining lower ash coal. It is possible that some poisoning or passivating elements are removed during the water-washing step.
EXAMPLE 6
A Splashdam seam coal (-20+40 mesh) assaying 8.8% ash was treated at 68° C. in 1.8 and 3.6 moles/l sulfuric acid solutions. The reaction time was 6 hours, and a platinum electrode was used at a potential of 1.0 V SCE. The results, given in Table VI, show that the ash removal was improved at a higher sulfuric acid concentration.
TABLE VI______________________________________Results of Ferric Ion Treatment on Splashdam Coal at DifferentElectrolyte Concentrations Coal Ash (% wt) RecoveryElectrolyte Feed Product (% wt)______________________________________1.8 M H.sub.2 SO.sub.4 8.8 2.5 97.23.63 M H.sub.2 SO.sub.4 8.8 1.5 96.2______________________________________
EXAMPLE 7
A graphitic anthracite, containing 15% ash and 0.46% sulfur, was processed by the present invention. A particle size of -60+100 mesh was chosen for preliminary tests with the stirred-tank cell (FIG. 2). The coal was treated at 65° C. in a mixture of 5% by weight hydrochloric and 15% sulfuric acid solutions. A potential of 1 V SCE was applied to a platinum-calomel electrode pair to regenerate the ferric ions. After 3 hours of initial treatment, the coal was cleaned to 11.6% ash and 0.08% sulfur, as shown in Table VII. The cleaned coal was treated again for 9 hours to obtain a coal containing 7.6% ash and 0.02% sulfur.
TABLE VII______________________________________Effect of Reaction Time on Ash Removal from aGraphitic Anthracite CoalReaction Time Product (% wt) Recovery(hours) Ash Sulfur Btu/lb (% wt)______________________________________1st stage 3 11.6 0.08 11,903 96.22nd stage 9 7.6 0.02 12,243 94.3______________________________________
EXAMPLE 8
A refuse filter cake from Glamorgan Coal Company, assaying 44% ash was treated by the present invention. The coal sample was processed as received, so that it contained a large amount of fines. The electrolyte solution consisted of 5% hydrochloric acid and 15% sulfuric acid by weight. A potential of 1.0 Y SCE was applied on a platinum electrode in the stirred-tank reactor (FIG. 2). After 4 hours of treatment at 65° C. the processed coal was washed of its liberated ash in a 400 mesh screen and an final product assayed 9.3% ash and 13,900 Btu/lb. The recovery was only 52.1% because much of the fine coal passed through the screen. A higher recovery would have been obtained if the processed coal had been cleaned of its liberated mineral matter using a process such as froth flotation or oil agglomeration.
EXAMPLE 9
An Upper Freeport coal (-28 mesh×0), assaying 24.5% ash and 1.68% sulfur, was treated in 2 moles/l hydrochloric acid solution for 5 hours using the stirred-tank reactor (FIG. 2). The ferric ions were regenerated on a platinum electrode at 1.0 V SCE.
After the initial 5-hour treatment the processed coal was washed of its liberated mineral matter in a 400 mesh screen. The cleaned coal, obtained as such, assayed 7.7% ash and 0.64% sulfur, as shown in Table VIII. The recovery was relatively low (65%) because a significant amount of the fine coal particles passed through the screen along with the liberated mineral matter. The cleaned coal was treated in the second stage in the same manner; the ash content was further reduced to 3.7%, but the sulfur content remained about the same. The coal reoovery was high (86%) because most of the fines had already been removed in the first stage.
TABLE VIII______________________________________Results of Ferric Ion Treatment on Upper Freeport Coal CoalReaction Time Product (% wt) Recovery(hours) Ash Sulfur (% wt)______________________________________1st stage 5 7.7 0.64 652nd stage 5 3.7 0.63 86______________________________________
EXAMPLE 10
The same Upper Freeport coal used in Example 9 was processed in combination with froth flotation and the microbubble flotation process. The -28 mesh×0 coal was subjected initially to froth flotation using a Denver laboratory flotation machine. After two stages of flotation, consuming 1.0 lb/ton of kerosene and 0.2 lb/ton of Dowfroth M-150, a clean coal product assaying 4.8% ash with 82.8% recovery was obtained. The clean coal product was pulverized for 15 minutes in an attrition mill to liberate the mineral matter in a conventional way. The mill product was subjected to four stages of microbubble flotation, consuming a total of 1.0 lb/ton of kerosene and 4.0 lb/ton of Dowfroth M-150. The ash content of the coal has reduced to 1.8% with 73.2% recovery.
The cleaned coal product from the microbubble flotation was subjected to the invented process. It was treated in 2.0 moles/l hydrochloric acid solution for 4 hours under the same conditions as described in Example 9. After the treatment, the coal slurry was subjected to single-stage microbubble flotation using 1.0 lb/ton of kerosene and 0.6 lb/ton of Dowfroth M-150. The cleaned coal product, obtained as such, assayed 1.16% ash and the coal recovery was 82% for the microbubble flotation alone and 60% overall including conventional flotation, ferric ion treatment and microbubble flotation processes.
EXAMPLE 11
In the examples presented heretofore, the spent ferric ions were regenerated by oxidizing the ferrous ions on the surface of a graphite or platinum electrode; the potentials of the electrodes were set above the equilibrium potential of the oxidation reaction. It was considered, however that as long as there is a sufficient amount of ferric ions present in the system, the Ferric Ion Treatment process can be effective without the use of the electrode and applied potential. To demonstrate this effect a set of experiments have been carried out using a relatively high concentration (26.6% by weight) of hydrated ferric sulfate (Fe 3 (SO 4 ) 2 .nH 2 O) alone. No attempts have been made to regenerate the spent ferric ions during the treatment, and no acids were used.
Coal samples from Norton seam, Splashdam seam and Blair seam have been used. In each test, a 20-gram sample was mixed with 100 ml of the ferric sulfate solution and left in a water bath at 60° C. To prevent the breakage of the coal particles, no mechanical stirring was applied, except for occasional agitation by hand. After 12 hours of treatment, the coal sample was wetscreened by hand using plenty of tap water. The liberated ash particles passed through the screen while the coal particles were retained on the screen; the Norton seam coal was washed using a 230 mesh screen while the Splashdam and Blair seam coals were washed using a 200 mesh screen.
The clean coal products remaining on the screen were then subjected to a simple skin flotation experiment in which the coal particles floating on the surface of the water were carefully skimmed off and analyzed. The results are given in Table IX. As shown, the Ferric Ion Treatment process can be effective without applying potentials to the slurry by means of an electrode.
TABLE IX__________________________________________________________________________Results of Ferric Ion treatment Without Regenerating the Spent FerricIonsNorton Seam Splashdam Seam Blair Seam(-100 + 230 mesh) (-80 + 200 mesh) (-140 + 200 mesh)Ash Coal Recovery Ash Coal Recovery Ash Coal RecoveryProduct(% wt) (% wt) (% wt) (% wt) (% wt) (% wt)__________________________________________________________________________Float3.3 14.7 1.8 34.3 1.2 50.7Screen12.68 71.4 2.5 92.5 1.7 99.3Feed 16.9 100.0 3.6 100.0 2.0 100.0__________________________________________________________________________
It has, thus, been seen that according to the present invention, ashforming mineral matter can be removed from a coal in a simple, effective, and energy-efficient manner. While the invention has herein been shown and described in what is presently conceived to be the most practical and preferred embodiment thereof it will be apparent to those of ordinary skill in the art that many modifications may be made thereof within the scope of the invention, the scope of which is to be accorded the broadest interpretation of the appended claims so as to encompass all equivalent methods products, and apparatus.
|
By Ferric Ion Treatment of crushed and/or pulverized coal, the ash content of a coal can be significantly and efficiently reduced. This treatment of coal, preferably in an acidic medium, creates an increase in osmotic pressure inside the pores and crevices of the coal matrix until they open up, allowing the ash-forming mineral matter to be released from the coal. Also, the ferric ions preferentially attack the sessile bonds of the coal molecule and help open up the pores. The liberated mineral matter is then separated from the coal to obtain a clean coal. A flow-through reactor, utilizing working, reference and counter electrodes, and a loosely-packed coal bed through which the electrolyte flows, is particularly effective in facilitating the Ferric Ion Treatment.
| 1
|
FIELD OF THE INVENTION
This invention relates to the discovery of Benzodiazepine analogs of Formula I for use as antagonists of cholecystokinin (CCK) and gastrin when administered to animals, preferably humans.
BACKGROUND OF THE INVENTION
The Benzodiazepine analogs of Formula I of this invention are useful in treating various diseases caused by an excess of CCK or gastrin. Cholecystokinins (CCK) and gastrin are structurally related neuropeptides which exist in gastrointestinal tissue and in the central nervous system (see, V. Mutt, Gastrointestinal Hormones, G. B. J. Glass, Ed., Raven Press, N.Y., p. 169 and G. Nission, ibid, p. 127.
Cholecystokinins include CCK-33, a neuropeptide of thirty-three amino acids in its originally isolated form (see, Mutt and Jorpes, Biochem. J. 125,678 (1971)), its carboxyl terminal octapeptide, CCK-8 (also a naturally-occurring neuropeptide and the minimum fully active sequence), and 39- and 12-amino acid forms. Gastrin occurs in 34-, 17- and 14-amino acid forms, with the minimum active sequence being the C-terminal tetrapeptide, TrP-Met-Asp-Phe-NH 2 , which is the common structural element shared by both CCK and gastrin.
CCK's are believed to be physiological satiety hormones, thereby possibly playing an important role in appetite regulation (G. P. Smith, Eating and Its Disorders, A. J. Stunkard and E. Stellar, Eds, Raven Press, New York, 1984, p. 67), as well as also stimulating colonic motility, gall bladder contraction, pancreatic enzyme secretion, and inhibiting gastric emptying. They reportedly co-exist with dopamine in certain mid-brain neurons and thus may also play a role in the functioning of dopaminergic systems in the brain, in addition to serving as neurotransmitters in their own right (see: A. J. Prange et al., "Peptides in the Central Nervous System", Ann. Repts. Med. Chem. 17, 31, 33 [1982] and references cited therein; J. A. Williams, Biomed. Res. 3 107 [1982]; and J. E. Morley, Life Sci. 30, 479, [1982]).
The primary role of gastrin, on the other hand, appears to be stimulation of the secretion of water and electrolytes in the stomach, and, as such, it is involved in control of gastric acid and pepsin secretion. Other physiological effects of gastrin then include increased mucosal blood flow and antral motility. Rat studies have shown that gastrin has a positive trophic effect on the gastric mucosa, as evidenced by increased DNA, RNA and protein synthesis. See e.g. U.S. Ser. No. 452,023 filed Aug. 26, 1991, now abandoned.
Antagonists to CCK and to gastrin are useful for preventing and treating CCK-related and/or gastrin-related disorders of the gastrointestinal (GI) and central nervous (CNS) systems of animals, preferably mammals, and especially those of humans. Just as there is some overlap in the biological activities of CCK and gastrin, antagonists also tend to have affinity for both receptors. In a practical sense, however, there is enough selectivity for the different receptors that greater activity against specific CCK- or gastrin-related disorders can often also be identified.
Selective CCK antagonists are themselves useful in treating CCK-related disorders of the appetite regulatory systems of animals as well as in potentiating and prolonging opiate-mediated analgesia, thus having utility in the treatment of pain [see P. L. Faris et al., Science 226, 1215 (1984)]. Selective gastrin antagonists are useful in the modulation of CNS behavior, as a palliative for gastrointestinal neoplasms, and in the treatment and prevention of gastrin-related disorders of the gastrointestinal system in humans and animals, such as peptic ulcers, Zollinger-Ellison syndrome, antral G cell hyperplasia and other conditions in which reduced gastrin activity is of therapeutic value. See e.g. U.S. Pat. No. 4,820,834. It is further expected that the CCK antagonists of Formula I are useful anxiolytic agents particularly in the treatment of panic and anxiety disorders.
Since CCK and gastrin also have trophic effects on certain tumors [K. Okyama, Hokkaido J. Med Sci., 60, 206-216 (1985)], antagonists of CCK and gastrin are useful in treating these tumors [see, R. D. Beauchamp et al., Ann. Surg., 202,303 (1985)].
Distinct chemical classes of CCK-receptor antagonists have been reported [R. Freidinger, Med. Res. Rev. 9, 271 (1989)]. The first class comprises derivatives of cyclic nucleotides, of which dibutyryl cyclic GMP has been shown to be the most potent by detailed structure-function studies (see, N. Barlas et al., Am. J. Physiol., 242, G 161 (1982) and P. Robberecht et al., Mol., Pharmacol., 17,268 (1980)).
The second class comprises peptide antagonists which are C-terminal fragments and analogs of CCK, of which both shorter (Boc-Met-Asp-Phe-NH 2 , Met-Asp-Phe-NH 2 ), and longer (Cbz-Tyr(SO 3 H)-Met-Gly-Trp-Met-Asp-NH 2 ) C-terminal fragments of CCK can function as CCK antagonists, according to recent structure-function studies (see, R. T. Jensen et al., Biochem. Biophys. Acta., 757, 250 (1983), and M. Spanarkel et al., J. Biol. Chem., 258, 6746 (1983)). The latter compound was recently reported to be a partial agonist [see, J. M. Howard et al, Gastroenterology 86(5) Part 2, 1118 (1984)].
The third class of CCK-receptor antagonists comprises the amino acid derivatives: proglumide, a derivative of glutaramic acid, and the N-acyl tryptophans including para-chlorobenzoyl-L-tryptophan (benzotript), [see, W. F. Hahne et al., Proc. Natl. Acad. Sci U.S.A., 78, 6304 (1981), R. T. Jensen et al., Biochem. Biophys. Acta., 761, 269 (1983)]. All of these compounds, however, are relatively weak antagonists of CCK (IC 50 : generally 10 -4 M[although more potent analogs of proglumide have been recently reported in F. Makovec et al., Arzneim-Forsch Drug Res., 35 (II), 1048 (1985) and in German Patent Application DE 3522506A1], but down to 10 -6 M in the case of peptides), and the peptide CCK-antagonists have substantial stability and absorption problems.
In addition, a fourth class consists of improved CCK-antagonists comprising a nonpeptide of novel structure from fermentation sources [R. S. L. Chang et al., Science, 230, 177-179 (1985)] and 3-substituted benzodiazepines based on this structure [published European Patent Applications 167 919, 167 920 and 169 392, B. E. Evans et al, Proc. Natl. Acad, Sci. U.S.A., 83, p. 4918-4922 (1986) and R. S. L. Chang et al, ibid, p. 4923-4926] have also been reported.
No really effective receptor antagonists of the in vivo effects of gastrin have been reported (j. S. Morley, Gut Pept. Ulcer Proc., Hiroshima Symp. 2nd, 1983, p. 1), and very weak in vitro antagonists, such as proglumide and certain peptides have been described [(J. Martinez, J. Med. Chem. 27, 1597 (1984)]. Recently, however, pseudopeptide analogs of tetragastrin have been reported to be more effective gastrin antagonists than previous agents [J. Martinez et al., J. Med. Chem., 28, 1874-1879 (1985)].
A new class of Benzodiazepine antagonist compounds has further been reported which binds selectively to brain CCK (CCK-B) and gastrin receptors [see M. Bock et al., J. Med. Chem., 32, 13-16 (1989)]. One compound of interest reported in this reference to be a potent and selective antagonist of CCK-B receptors is (R)-N-(2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl)-N.sup.1 -(3-methylphenyl) urea (See U.S. Pat. No. 4,820,834.) One disadvantage of the new CCK-B compound reported in Bock et al., J. Med. Chem., 32, 13-16 (1989) and U.S. Pat. No. 4,820,834, is that these CCK-B compounds are poorly water soluble.
It is, therefore, an object of the present invention to provide antagonists of CCK and gastrin. If an antagonist compound could be prepared which would bind with the cell surface receptor of CCK or gastrin, then the antagonist compounds of this invention could be used to block the effect of CCK and gastrin. Another object of the present invention is to provide novel CCK and gastrin antagonist compounds which are water soluble. Other objects of the present invention are to provide methods of inhibiting the action of CCK and gastrin through the administration of novel benzodiazepine analog compounds. The above and other object are accomplished by the present invention in the manner more fully described below.
SUMMARY OF THE INVENTION
The present invention provides Benzodiazepine analogs of the formula: ##STR2## for use as antagonists of CCK and gastrin. The above-mentioned compounds can be used in a method of acting upon a CCK and/or gastrin receptor which comprises administering a therapeutically effective but non-toxic amount of such compound to an animal, preferably a human. A pharmaceutical composition comprising a pharmaceutically acceptable carrier and, dispersed therein, an effective but non-toxic amount of such compound is another aspect of this invention.
DETAILED DESCRIPTION OF THE INVENTION
Benzodiazepine analogs of Formula I provide antagonists of CCK and gastrin. The present invention further provides novel CCK and gastrin antagonist compound which are water soluble. The Benzodiazepine analogs of Formula I are useful in a method of antagonizing the binding of CCK to CCK receptors or antagonizing the binding of gastrin to gastrin receptors. The novel Benzodiazepine analogs of the present invention are illustrated by compounds having the formula: ##STR3## R is ##STR4## R 1 is C 1 -C 6 linear or branched chain alkyl or cyclopropyl; R 2 is unsubstituted or substituted phenyl where the substituent is fluoro, chloro, bromo, iodo, nitro, carboxy, hydroxy, amino, hydroxy C 1 -C 4 -alkyl, C 1 -C 4 -mono or di-alkyl amino; or cyclohexyl;
or the optical isomers, prodrugs or pharmaceutically acceptable salts thereof.
The preferred compounds of this invention as set forth in the Examples are as follows:
1. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-tertbutyloxycarbonylamino-2-methoxycarbonyl) ethylphenyl]urea},
2. N-{(3R )-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-{[3-((2S)-aminomethoxycarbonyl )ethylphenyl ]-urea},
3. N-{(3R )-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-carboxy)ethylphenyl ]-urea},
4. N-{(3R)-1, 3-Dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-tertbutyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea},
5. N-{(3R )-1,3-Dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl }-N'-{[3-((2S)-amino-2methoxycarbonyl)ethylphenyl]-urea},
6. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-carboxy)ethylphenyl]-urea},
7. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-tertbutyloxycarbonylamino-1-methoxycarbonyl)methylphenyl]-urea},
8. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-amino-1methoxycarbonyl)methylphenyl]-urea},
9. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-amino-1-carboxy)methylphenyl]-urea},
10. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R)-amino-1-carboxy)methylphenyl]-urea},
11. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R, S)-tertbutyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea},
12. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R, S)-amino-2methoxycarbonyl)ethylphenyl]-urea},
13. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R, S)-amino-2carboxy)ethylphenyl]-urea},
14. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[8-(methyl-2-(R, S)tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea},
15. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R, S)tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea},
16. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R, S)amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea},
17. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(2-(R, S)-amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea},
18. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(methyl-2-(R, S)tert-butyloxycarbonylamino-1,2,3,4-tetrahydronaphthoate)]-urea},
19. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(methyl-2-(R, S)amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea},
20. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea},
21. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(methyl-2-(R,S)tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea},
22. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(methyl-2-(R, S)amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}, or
23. N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea},
or the pharmaceutically acceptable salts thereof.
The most preferred compounds of this invention as set forth in the Examples are as follows: ##STR5## or the pharmaceutically acceptable salts thereof.
It will be appreciated that formula (I) is intended to embrace all possible isomers, including optical isomers, and mixtures thereof, including racemates.
The present invention includes within its scope prodrugs of the compounds of formula I above. In general, such prodrugs will be functional derivatives of the compounds of formula I which are readily convertible in vivo into the required compound of formula I. Conventional procedures for the selection and preparation of suitable prodrug derivatives are described, for example, in "Design of Prodrugs", ed. H. Bungaard, Elsevier, .1985.
The pharmaceutically acceptable salts of the compounds of Formula I include the conventional non-toxic salts or the quarternary ammonium salts of the compounds of Formula I formed, e.g., from non-toxic inorganic or organic acids. For example, such conventional non-toxic salts include those from inorganic acids such as hydrochloric, hydrobromic, sulfuric, sulfamic, phosphoric, nitric and the like; and the salts prepared from organic acids such as acetic, propionic, succinic, glycolic, stearic, lactic, malic, tartaric, citric, ascorbic, pamoic, maleic, hydroxymaleic, phenylacetic, glutamic, benzoic, salicylic, sulfanilic, 2-acetoxybenzoic, fumaric, toluenesulfonic, methanesulfonic, ethane disulfonic, oxalic, isethionic, and the like.
The pharmaceutically acceptable salts of the present invention can be synthesized from the compounds of Formula I by conventional chemical methods. Generally, the salts are prepared by reacting the Formula I compound with stoichiometric amounts or with an excess of the desired salt-forming inorganic or organic acid or base in a suitable solvent or various combinations of solvents.
The pharmaceutically acceptable salts of the acids of Formula I are also readily prepared by conventional procedures such as treating compounds of Formula I with an appropriate amount of a base, such as an alkali or alkaline earth metal hydroxide e.g. sodium, potassium, lithium, calcium, or magnesium, or an organic base such as an amine, e.g., dibenzylethylenediamine, trimethylamine, piperidine, pyrrolidine, benzylamine and the like, or a quaternary ammonium hydroxide such as tetramethylammonium hydroxide and the like.
The compounds of Formula I antagonize CCK and/or gastrin and are useful as pharmaceutical agents for animals, preferably for mammals, and most especially for humans, for the treatment and prevention of gastrointestinal disorders and central nervous system disorders.
Examples of such gastrointestinal disorders include ulcers, such as peptic and gastrointestinal ulcers, irritable bowel syndrome, gastroesophagenal reflux disease or excess pancreatic or gastrin secretion, acute pancreatitis, or motility disorders, Zollinger-Ellison syndrome, and antral and cell hyperplasia.
Examples of central nervous system disorders include central nervous system disorders caused by CCK interaction with dopamine, such as neuroleptic induced tardive dyskinesia, Parkinson's disease, schizophrenia, other psychosis or Gilles de la Tourerrs syndrome, and disorders of appetite regulatory systems.
The compounds of Formula I may further be useful in the treatment or prevention of additional central nervous system disorders including neurological and psychiatric disorders. Examples of such central nervous system disorders include anxiety disorders and panic disorders, wherein CCK and/or gastrin is involved. Additional examples of central nervous system disorders include panic syndrome, anticipatory anxiety, phobic anxiety, panic anxiety, chronic anxiety, and endogeneous anxiety.
The compounds of Formula I may further be useful in the treatment of oncologic disorders wherein CCK or gastrin may be involved. Examples of such oncologic disorders include small cell adenocarcinomas and primary tumors of the central nervous system glial and neuronal cells. Examples of such adenocarcinomas and tumors include, but are not limited to, tumors of the lower esophagus, stomach, intestine, colon and lung, including small cell lung carcinoma.
The compounds of Formula I may further be used to control pupil constriction in the eye. The compounds may be used for therapeutic purposes during eye examinations and intraocular surgery in order to prevent miosis. The compounds may further be used to inhibit miosis occurring in association with iritis, uveitis and trauma.
The compounds of Formula I are also useful for directly inducing analgesia, opiate or non-opiate mediated, as well as anesthesia or loss of the sensation of pain.
The compounds of Formula I may further be useful for preventing or treating the withdrawal response produced by chronic treatment or abuse of drugs or alcohol. Such drugs include, but are not limited to, cocaine, alcohol or nicotine.
The compounds of Formula I are also useful for directly inducing analgesia, opiade or non-opiade mediated, as well as anesthesia or loss of the sensation of pain.
The compounds of formula (I) may also be useful as neuroprotective agents, for example, in the treatment and/or prevention of neurodegenerative disorders arising as a consequence of such pathological conditions as stroke, hypoglycaemia, cerebal palsy, transient cerebral ischaemic attack, cerebral ischaemia during cardiac pulmonary surgery or cardiac arrest, perinatal asphyxia, epilepsy, Huntington's chorea, Alzheimer's disease, Amyotrophic Lateral Sclerosis, Parkinson's disease, Olivo-pontocerebellar atrophy, anoxia such as from drowning, spinal cord and head injury, and poisoning by neurotoxins, including environmental neurotoxins.
The compounds of Formula I may also be useful in the treatment of depression. Depression can be the result of organic disease, secondary to stress associated with personal loss, or idiopathic in origin. There is a strong tendency for familial occurrence in some forms of depression suggesting a mechanistic cause for at least some forms of depression. The diagnosis of depression is made primarily by quantification of alterations in a patients' mood. These evaluations of mood are generally performed by a physician or quantified by a neuropsychologist using validated rating scales such as the Hamilton Depression Rating Scale or the Brief Psychiatric Rating Scale. Numerous other scales have been developed to quantify and measure the degree of mood alterations in patients with depression, such as insomnia, difficulty with concentration, lack of energy, feelings of .worthlessness, and guilt. The standards for diagnosis of depression as well as all psychiatric diagnoses are collected in the diagnostic and Statistical Manual of Mental Disorders (Third Edition Revised) referred to as the DSM-III-R manual published by the American Psychiatric Association, 1987.
The present invention also encompasses a pharmaceutical composition useful in the treatment of CCK and/or gastrin disorders comprising the administration of a therapeutically effective but non-toxic amount of the compounds of Formula I, with or without pharmaceutically acceptable carriers or diluents.
The compounds of Formula I, may be administered to animals, preferably to mammals, and most especially to a human subject either alone or, preferably, in combination with pharmaceutically-acceptable carriers or diluents, optionally with known adjuvants, such as alum, in a pharmaceutical composition, according to standard pharmaceutical practice. The compounds can be administered orally or parenterally, including intravenous, intramuscular, intraperitoneal, subcutaneous and topical administration.
For oral use of an antagonist of CCK, according to this invention, the selected compounds may be administered, for example, in the form of tablets or capsules, or as an aqueous solution or suspension. In the case of tablets for oral use, carriers which are commonly used include lactose and corn starch, and lubricating agents, such as magnesium stearate, are commonly added. For oral administration in capsule form, useful diluents include lactose and dried corn starch. When aqueous suspensions are required for oral use, the active ingredient is combined with emulsifying and suspending agents. If desired, certain sweetening and/or flavoring agents may be added. For intramuscular, intraperitoneal, subcutaneous and intravenous use, sterile solutions of the active ingredient are usually prepared, and the pH of the solutions should be suitably adjusted and buffered. For intravenous use, the total concentration of solutes should be controlled in order to render the preparation isotonic.
When a compound according to Formula I is used as an antagonist of CCK or gastrin in a human subject, the daily dosage will normally be determined by the prescribing physician with the dosage generally varying according to the age, weight, and response of the individual patient, as well as the severity of the patient's symptoms. However, in most instances, an effective daily dosage will be in the range of from about 0.005 mg/kg to about 50 mg/kg of body weight, and preferably, of from about 0.05 mg/kg to about 50 mg/kg of body weight, and most preferably, of from about 0.5 mg/kg to about 20 mg/kg of body weight, administered in single or divided doses.
In the effective treatment of panic syndrome, panic disorder, anxiety disorder and the like, preferably about 0.05 mg/kg to about 1.0 mg/kg of CCK antagonist may be administered orally (p.o.), administered in single or divided doses per day (b.i.d.). Other routes of administration are also suitable.
For directly inducing analgesia, anesthesia or loss of pain sensation, the effective dosage range is preferably from about 100 ng/kg to about 1 mg/kg by intraperitoneal administration. Oral administration is an alternative route, as well as others.
In the treatment of irritable bowel syndrome, preferably about 0.1 to 10 mg/kg of CCK antagonist is administered orally (p.o.), administered in single or divided doses per day (b.i.d.). Other routes of administration are also suitable.
The use of a gastrin antagonist as a tumor palliative for gastrointestinal neoplasma with gastrin receptors, as a modulator of central nervous activity, treatment of Zollinger-Ellison snydrome, or in the treatment of peptic ulcer disease, an effective dosage is preferably from about 0.1 to about 10 mg/kg, administered one-to-four times daily is indicated.
Because these compounds antagonize the function of CCK in animals, they may also be used as feed additives to increase the food intake of animals in daily dosage preferably from about 0.05 mg/kg to about 50 mg/kg of body weight.
The compounds of Formula I may be prepared according to the reaction schemes as set forth below. ##STR6##
1. CCK Receptor Binding (Pancreas)
CCK-8 sulphated was radiolabelled with 125 I-Bolton Hunter reagent (2000 Ci/mmole). Receptor binding was performed according to Chang and Lotti (Proc. Natl. Acad. Sci. 83, 4923-4926, 1986) with minor modifications.
Male Sprague-Dawley rats (150-200 g) were sacrificed by decapitation. The whole pancreas was dissected free of fat tissue and was homogenized in 25 volumes of ice-cold 10 mM Hepes buffer with 0.1% soya bean trypsin inhibitor (pH 7.4 at 25° C.) with a Kinematica Polytron. The homogenates were centrifuged at 47,800 g for 10 min. Pellets were resuspended in 10 volumes of binding assay buffer (20 mM Hepes, 1 mM EGTA, 5 mM MgCl 2 , 150 mM NaCl, bacitracin 0.25 mg/ml, soya bean trypsin inhibitor 0.1 mg/ml, and bovine serum albumin 2 mg/ml, pH 6.5 at 25° C.) using a teflon homogenizer, 15 strokes at 500 rpm. The homogenate was further diluted in binding assay buffer to give a final concentration of 0.5 mg original wet weight/l ml buffer. For the binding assay, 50 μl of buffer (for total binding) or unlabeled CCK-8 sulfated to give a final concentration of 1 μM (for nonspecific binding) or the compounds of Formula I (for determination of inhibition of 125 I-CCK binding) and 50 μl of 500 pM 125 I-CCK-8 (i.e. 50 pM final concentration) Were added to 400 μl of the membrane suspensions in microfuge tubes. All assays were run in duplicate. The reaction mixtures were incubated at 25° C. for 2 hours and the reaction terminated by rapid filtration (Brandell 24 well cell harvester) over Whatman GF/C filters, washing 3×4 mls with ice-cold 100 mM NaCl. The radioactivity on the filters was counted with a LKB gamma counter.
2. CCK Receptor Binding (Brain)
CCK-8 sulphated was radiolabelled and the binding was performed according to the description for the pancreas method with minor modifications.
Male Hartley guinea pigs (300-500g) were sacrificed by decapitation and the cortex was removed and homogenized in 25 mL ice-cold 0.32M sucrose. The homogenates were centrifuged at 1000 g for 10 minutes and the resulting supernatant was recentrifuged at 20,000 g for 20 minutes. The P 2 pellet was resuspended in binding assay buffer (20 mM N-2-hydroxyethyl-piperazine-N'-2-ethane sulfonic acid (HEPES), 5 mM MgCl 2 , 0.25 mg/ml bacitracin, 1 mM ethylene glycol-bis-(B-aminoethylether-N,N'-tetraacetic acid) (EGTA)pH 6.5 at 25° C., using a teflon homogenizer (5 strokes at 500 rpm) to give a final concentration of 10 mg original wet weight 11.2 mls buffer. For the binding assay, 50 μl of buffer (for total binding) or unlabeled CCK-8 sulfate to give a final concentration of 1 μM (for nonspecific binding) or the compounds of Formula I (for determination of inhibition of 125 I-CCK-8 binding) and 50 μ l of 500 pM 125 I-CCK-8 (i.e. final concentration of 50 pM) were added to 400 μl of the membrane suspensions in microfuge tubes. All assays were run in duplicate. The reaction mixtures were incubated at 25° C. for 2 hours and then the reaction was terminated on Whatman GF/C filters by rapid filtration (Brandell 24 well cell Harvester) with 3×5 ml washes of cold 100 mM NaCl. The radioactivity on the filters was then counted with a LKB gamma counter.
5. Gastrin Antagonism
Gastrin antagonist activity of compounds of Formula I is determined using the following assay.
A. Gastrin Receptor Binding in Guinea Pig Gastric Glands
Preparation of guinea pig gastric mucosal glands
Guinea pig gastric mucosal glands were prepared by the procedure of Chang et al., Science 230, 177-179 (1985) with slight modification. Gastric mucosa from guinea pigs (300-500 g body weight, male Hartley) were isolated by scraping with a glass slide after washing stomachs in ice-cold, aerated buffer consisting of the following: 130 mM NaCl, 12 mM NaHCO 3 , 3 mM NaH 2 PO 4 , 3 mM Na 2 HPO 4 , 3 mM K 2 HPO 4 , 2 mM MgSO 4 , 1 mM CaCl 2 , 5 mM glucose and 4 mM L-glutamine, 50 mM HEPES, 0.25 mg/ml bacitracin, 0.10 mg/ml soya bean trypsin inhibitor, 0.1 mg/ml bovine serum albumin, at pH 6.5, and then incubated in a 37° C. shaking water bath for 40 minutes in buffer containing 1 mg/ml collagenase and bubbled with 95% O 2 and 5% CO 2 . The tissues were passed twice through a 5 ml syringe to liberate the gastric glands, and then filtered through Nitex #202 gauge nylon mesh. The filtered glands were centrifuged at 272 g for 5 minutes and washed twice by resuspension in 25 ml buffer and centrifugation.
B. Binding Studies
The washed guinea pig gastric glands prepared as above were resuspended in 25 ml of standard buffer. For binding studies, to 250 μl of gastric glands, 30 μl of buffer (for total binding) or gastrin (3 μM final concentration, for nonspecific binding) or test compound and 20 μl of 125 I-gastrin (NEN, 2200 Ci/mmole, 0.1 nM final concentration) were added. AV assays were run in triplicate. The tubes were aerated with 95% O 2 and 5% CO 2 and capped. The reaction mixtures after incubation at 25° C. for 30 minutes in a shaking water bath were rapidly filtered (Brandell 24 well cell harvester) over Whatman and G/F B filters presoaked in assay buffer and immediately washed further with 3×4 ml of 100mM ice cold NaCl. The radioactivity on the filters was measured using a LKB gamma counter.
In Vitro Results
Effect of The Compounds of Formula I on 125 I-CCK-8 receptor binding
The preferred compounds of Formula I are those which produced dose-dependent inhibition of specific 125 I-CCK-8 binding as defined as the difference between total and non-specific (i.e. in the presence of 1 μm CCK) binding.
Drug displacement studies were performed with at least 10 concentrations of compounds of formula 1 and the IC 50 values were determined by regression analysis. IC 50 refers to the concentration of the compound required to inhibit 50% of specific binding of 125 I-CCK-8.
The data in Table I were obtained for compounds of Formula I.
TABLE I______________________________________CCK RECEPTOR BINDING RESULTSIC.sub.50 (μM)Compound .sup.125 I-CCK .sup.125 I-CCKof Example Pancreas Brain______________________________________ 1. >3 0.0296 2. >>3 0.114 3. >>3 0.0613 4. 0.961 0.0039 5. 0.924 0.0092 6. 1.786 0.0011 7. >>3 1.98 8. >>3 0.958 9. >3 1.3310. >>3 3.5911. >3 0.38612. >>3 >313. >3 >314. >3 0.64715. >3 0.12616. >3 0.14817. >3 0.028418. >>3 >319. >3 >320. >3 3.5221. >3 1.6922. >3 2.1623. >>3 >3______________________________________
EXAMPLES
Examples provided are intended to assist in a further understanding of the invention. Particular materials employed, species and conditions are intended to be further illustrative of the invention and not limitative of the reasonable scope thereof.
EXAMPLE 1
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-tertbutyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]urea}
Part 1: Methyl 3-(4-Triflyl-3-nitrophenyl)-2(S)-tertbutyloxy carbonyl-aminopropionate (B)
To an ice cold solution of 25 ml of methylene chloride under nitrogen containing 3 g of 3-(4-hydroxy-3-nitrophenyl)-N.sup.α -Boc-L-alanine methyl ester A and 1.61 ml of diisopropylethylamine was added 1.55 ml of triflic anhydride over a 20 minute period. The reaction mixture was stirred at 0° C. for 30 minutes more and then was concentrated under reduced pressure. The residual material was plug-filtered through silica gel using ethyl acetate-hexane (1:1 v/v) as eluant. The title compound was obtained as a solid (1.624 g).
Part 2: Methyl 3-(3-Aminophenyl)-2(S)-tertbutyloxycarbonylaminopropionate (C)
Methyl 3-(4-triflyl-3-nitrophenyl)-2(S)-tertbutyloxycarbonylaminopropionate (730 mg), diisopropylethylamine (295 mL) and 365 mg of 10% palladium/carbon catalyst were combined in 50 mL of methanol and hydrogenated on a Parr apparatus at 55 p.s.i. for 60 minutes. The reaction mixture was filtered and concentrated. The residue was dissolved in a minimum amount of chloroform and applied to a silica gel column; flash chromatography (hexane-ethyl acetate elution 1:1, v/v) afforded 346 mg of the title compound.
Part 3.: N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]urea}
A solution of methyl 3-(3-aminophenyl)-2(S)tert-butyloxycarbonylaminopropionate(C) (332 mg>in 30 mL of tetrahydrofuran was stirred magnetically in an ice bath under a nitrogen atmosphere and treated in sequence with triethylamine (472 mL) and triphosgene (112 mg) under anhydrous conditions. The pH of the reaction mixture was adjusted to approximately 8 with the incremental addition of triethylamine. The reaction mixture was warmed to room temperature for 10 minutes and recooled to 0° C. A solution of 10 mL of tetrahydrofuran containing 270 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2- one was then added dropwise over a five minute period. The reaction mixture was stirred fifteen minutes more and was then partitioned between ethyl acetate-10% citric acid solution. The aqueous layer was extracted with ethyl acetate and the combined organic extracts were washed with brine, dried (sodium sulfate), and roto-evaporated. Flash chromatography of the crude reaction product on silica gel (ethyl acetate-hexane elution, 3:2 v/v) afforded the title compound (534mg) as a solid: m.p. 135°-138° C. (d).
HPLC=>99% pure at 214 nm; TLC R f =0.58 (CH 2 Cl 2 --CH 3 OH--HOAc--H 2 O, 90:10:1:1). NMR(CDCl 3 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 586 (M + +1). Analysis for C 32 H 35 N 5 O 6 •0.15H 2 O•0.55EtOAc: Calculated: C, 64.50; H, 6.28; N, 11.00. Found: C, 64.47; H, 6.30; N, 11.00.
EXAMPLE 2
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-methoxycarbonyl)ethylphenyl]-urea}
A solution of 350 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N,-{[3-((2S)-tert-butyloxycarbonylamino-2-methoxxcarbonyl)ethylphenyl]-urea}in 15 mL of ethyl acetate was cooled to 0° C. under nitrogen. A steady stream of hydrogen chloride gas was passed through the reaction mixture for 10 minutes during which time a precipitate was formed. The reaction vessel was sealed and the reaction mixture was stirred for an additional 30 minutes. All volatiles were removed under reduced pressure and the residual material was chromatographed on silica gel (chloroform:methanol:concentrated ammonium hydroxide, 90:10:1 v/v) to give 284 mg of the title compound as a solid: m.p. 127°-129° C. (d). HPLC=99% pure at 214 rim; TLC R f =0.23 (CH 2 Cl 2 --CH 3 OH--HOAc--H 2 O, 90:10:1:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 486 (M + +1). Analysis for C 27 H 27 N 5 O 4 •0.7CHCl 3 •0.2CH 3 OH: Calculated: C, 58.23; H, 4.99; N, 12.17. Found: C, 58.25; H, 4.94; N, 12.15.
EXAMPLE 3
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-carboxy)ethylphenyl]-urea}
Triethylamine (63 mL) and 217 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-methoxycarbonyl)ethylphenyl]-urea} were combined in a dioxane-water mixture (2:1, v/v) and stirred at room temperature. The progress of the reaction was monitored by HPLC. After 11 days the solvent was roto-evaporated and the crude product was purified by preparative thick layer chromatography on pre-coated silica gel plates (1 mm thickness, CHCl 3 --CH 3 OH--HOAc--H 2 O, 90:10:1:1). The product was extracted from the silica gel with chloroform-methanol (88:12 v/v) to give 72 mg of the title compound as its triethylamine salt. This material was further worked-up by preparative reverse phase HPLC (Vydac C-18 column, acetonitrile-water (containing 0.01% trifluoroacetic acid), 8 mL/min flow rate, 45 minute gradient) to yield, after lyophilization, 59 mg of the title compound as a solid: m.p. 195° C. (d). HPLC=99% pure at 214 nm; TLC R f =0.44 (EtOAc-pyridine--HOAc--H 2 O, 10:5:1:3). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 472 (M + +1). Analysis for C 25 H 25 N 5 O 4 •1.6 TFA•1.0 H 2 O: Calculated: C, 52.17; H, 4.29; N, 10.42. Found: C, 52.15; H, 4.25; N, 10.47.
EXAMPLE4
N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl}-N'-{[ 3-((2S)-tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea}.
A solution of methyl 3-(3-aminophenyl)-2(S)-tert-butyloxycarbonylaminopropionate(C) (108 mg) in 10 mL of tetrahydrofuran was stirred magnetically in an ice bath under a nitrogen atmosphere and treated in sequence with triethylamine (155 mL) and triphosgene (37 mg) under anhydrous conditions. The pH of the reaction mixture was adjusted to approximately 8 with the incremental addition of triethylamine. The reaction mixture was stirred for minutes at 0° C. warmed to room temperature for 8 minutes and recooled to 0° C. A solution of 3 mL of tetrahydrofuran containing 100 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-cyclohexyl-2H-1,4-benzo-diazepin-2-one was then added dropwise over a five minute period. The reaction mixture was stirred twenty minutes more and was then partitioned between ethyl acetate-10% citric acid solution. The aqueous layer was extracted with ethyl acetate-and the combined organic extracts were washed with brine, dried (sodium sulfate), and roto-evaporated. Preparative thick layer chromatography of the crude reaction product on pre-coated silica gel plates (1 mm thickness, CHCl 3 --CH 3 OH elution, 90:10 v/v) afforded the title compound as a solid: m.p. 139°-143° C. (d). HPLC=99% pure at 214 nm; TLC R f =0.50 (CH 2 Cl 2 --CH 3 OH--HOAc--H 2 O, 90:10:1:1). NMR(CDCl.sub. 3): Consistent with structure assignment and confirms presence of solvent. FAB MS: 592 (M + 1). Analysis for C 32 H 41 N 5 O 6 •0.10 CHCl 3 •0.50 EtOAc: Calculated: C, 63.24; H, 7.02; N, 10.81. Found: C, 63.25; H, 6.71; N, 10.58.
EXAMPLE 5
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5- cyclohexyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2-methoxycarbonyl)ethylphenyl]-urea}
A solution of 139 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3yl}-N'-{[3-((2S)-tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea} in 10 mL of ethyl acetate was cooled to 0° C. under nitrogen. A steady stream of hydrogen chloride gas was passed through the reaction mixture for 10 minutes. The reaction vessel was sealed and the reaction mixture was stirred for an additional 30 minutes. All volatiles were removed under reduced pressure to give 143 mg of the title compound as a solid: m.p. 184° C. (d). HPLC=>98% pure at 214 nm; TLC R f =0.50 (CHCl 3 --CH 3 OH--NHOH, 90:10:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 492 (M + 1). Analysis for C 26 H 33 N 5 O 4 •2.5 HCl•0.7 EtOAC: Calculated: C, 54.70; H, 6.55; N, 11.07. Found: C, 54.74; H, 6.19; N, 11.08.
EXAMPLE 6
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl }-N'-{[3-((2S )amino-2-carboxy)ethylphenyl]-urea}
Lithium hydroxide hydrate (26 mg) and 125 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-cyclohexyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((2S)-amino-2methoxycarbonyl)ethylphenyl]-urea} were combined in a tetrahydrofuran-water mixture (2:3, v/v) and stirred at room temperature for three hours. An additional 8 mg of lithium hydroxide hydrate was added and stirring was continued for 30 minutes more. The solvent was roto-evaporated and the crude product was purified by preparative reverse phase HPLC (Vydac C-18 column, acetonitrile-water (containing 0.1% trifluoroacetic acid), 8 mL/min flow rate, 45 minute gradient) to yield, after lyophilization, 59 mg of the title compound as a solid: m.p. 135°-139° C. (d). HPLC=99% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 478 (M + +1). Analysis for C 25 H 31 N 5 O 4 •1.95 TFA•0.7 H 2 O: Calculated: C, 50.40; H, 4.86; N, 9.83. Found: C, 50.37; H, 4.83; N, 10.10.
EXAMPLE 7
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-tert-butyloxycarbonylamino-1-methoxycarbonyl)methylphenyl]-urea}
Part 1: (S)-Amino-(3-nitrophenyl)acetic acid (D)
A solution of L-phenylglycine (10 g) in 40 mL of conc. sulfuric acid was cooled in an ice water/acetone bath. 90% Nitric acid (3.72 mL) was added dropwise over a 30 minute period at such a rate as to keep the internal temperature below 10° C. After addition was complete, stirring was continued for 1 hour at 0° C. and then the reaction mixture was allowed to warm to room temperature over 1.5 hours. The reaction mixture was poured onto 200 g of crushed ice and the resulting mixture was neutralized with sodium hydroxide to pH 7. The reaction mixture was diluted with 600 mL of water, Celite was added and the resulting suspension was filtered and concentrated to give the crude product D contaminated with sodium sulfate. This material was taken to the next step without further purification.
Part 2: Methyl (S)-tert-Butyloxycarbonylamino-(3-nitrophenyl)acetate (E)
Crude (S)-amino-(3-nitrophenyl)acetic acid (66 mmole) was mixed with 2.64 g of sodium hydroxide in 150 mL of water. The resulting slurry was filtered and the filtrate was concentrated and redissolved in 50 mL of water. .To this suspension was added 50 mL of tert-butanol, followed by the dropwise addition over a 30 minute period of 50 mL of tert-butanol containing 15.8 g of di-tert-butyldicarbonate. The reaction mixture was stirred at room temperature for 2 hours, was diluted with 250 mL of water, and then extracted with pentane (3×150 mL). The aqueous layer was acidified to pH 3 with sodium bisulfate approximately 9 g) and extracted with ethyl acetate. The combined organic extracts were dried (Na 2 SO 4 ) and concentrated. The crude product was azeotropically dried with toluene to afford 12 g of the (S)-tert-butyloxycarbonylamino-(3-nitrophenyl)acetic acid. This material was dissolved in 110 mL of N,N-dimethylformamide and treated with 55 g (10 equivalents) of sodium bicarbonate and 20.5 mL of iodomethane. The resulting suspension was stirred under nitrogen for 1.5 hours, filtered, and concentrated under reduced pressure. The residual product was partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate and the combined organic extracts were washed with brine, dried, and concentrated. Flash chromatography of the crude product on silica gel (ethyl acetate-hexane elution, 1:2 v/v) gave 11.07g of the pure title compound.
Part 3: Methyl (S)-tert-Butyloxycarbonylamino-(3-aminophenyl)acetate (F)
Methyl (S)-tert-butyloxycarbonylamino-(3-nitrophenyl)acetate (3 g) and 200 mg of 10% palladium on carbon catalyst were combined in 100 mL of methanol and hydrogenated on a Parr apparatus at 50 p.s.i. for 110 minutes. The reaction mixture was filtered and concentrated. The residue was azeotropically dried with toluene to give 2.4 g of the title compound.
Part 4: N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)tert-butyloxycarbonylamino-1-methoxycarbonyl)methylphenyl]urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl (S)-tert-butyloxycarbonylamino-(3-aminophenyl)acetate (F) (557 mg) in 50 mL of tetrahydrofuran was reacted with 197 mg of triphosgene, 832 mL of triethylamine, and 475 mg of 1,3-dihydro-l-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2-one in 15 mL of tetrahydrofuran. The crude reaction product was flash chromatographed on silica gel (ethyl acetatehexane elution, 3:2 v/v) to give the title compound (989 mg) as a solid: m.p. 164°-166° C. (d). HPLC=99% pure at 214 nm; TLC R f =0.51 (EtOAc-hexane,3:2). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 572 (M + +1). Analysis for C 31 H 33 N 5 O 6 •0.25 Hexane•0.6EtOAc: Calculated: C, 64.89; H, 6.44; N, 10.84. Found: C, 64.86; H, 6.59; N, 10.90.s
EXAMPLE 8
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S )-amino-1-methoxycarbonyl)methylphenyl]-urea}
Utilizing reaction conditions identical to those described in Example 2,737 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-tert-butyloxycarbonylamino-1-methoxycarbonyl)methylphenyl]-urea} was converted to the title compound which was obtained as a solid after chromatography on silica gel (chloroform: methanol:concentrated ammonium hydroxide, 90:10:1 v/v); yield 515 mg: m.p. 134°-136° C. (d). HPLC=99% pure at 214 nm; TLC R f =0.40 (CHCl 3 --CH 3 OH--NH 4 OH, 90:10:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 472 (M + +1). Analysis for C 26 H 25 N 5 O 4 •1.65 H 2 O: Calculated: C, 62.30; H, 5.69; N, 13.97. Found: C, 62.24; H, 5.30; N, 14.32.
EXAMPLE 9
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-amino-1-carboxy)methylphenyl]-urea}
Lithium hydroxide hydrate (24 mg) and 255 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-amino-2-methoxycarbonyl)methylphenyl]-urea} were combined in a 1:1 tetrahydrofuran-water mixture (4 mL) and stirred at room temperature for thirty minutes. The solvent was roto-evaporated and the crude product was purified by preparative thick layer chromatography on pre-coated silica gel plates (0.5 mm thickness) (initial elution with CHCl 3 --MeOH--HOAc--H 2 O, 90:10:1:1, then double elution with CHCl 3 --MeOH--HOAc--H 2 O, 85:15:1.5:1.5). Two components were isolated from the silica gel plates. The higher R f component was further purified by preparative HPLC (Vydac C-18 column, acetonitrile-water (containing 0.1% trifluoroacetic acid), 8 mL/min flow rate,45 minute gradient) to give the title compound (39 mg) as a homogeneous white solid: m.p 191° C. (d). HPLC=99% pure at 214 nm, Rf=0.44 (EtOAc:pyridine:HOAc:H 2 O; 10:5:1:3) NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 458 (M + +1). Analysis for C 25 H 23 N 5 O 4 •1.55 TFA•0.65 H 2 O: Calculated: C, 52.23; H, 4.03; N, 10.84. Found: C, 52.25; H, 4.06; N, 10.81.
EXAMPLE 10
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R)-amino-1 -carboxy)methylphenyl]-urea}
Lithium hydroxide hydrate (24 mg) and 255 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1S)-amino-2-methoxycarbonyl)methylphenyl]-urea} were combined in a 1:1 tetrahydrofuran-water mixture (4 mL) and stirred at room temperature for thirty minutes. The solvent was roto-evaporated and the crude product was purified by preparative thick layer chromatography on pre-coated silica gel plates (0.5 mm thickness) (initial elution with CHCl 3 --MeOH--HOAc-H 2 O, 90:10:1:1, then double elution with CHCl 3 --MeOH--HOAc--H 2 O, 85:15:1.5:1.5). Two components were isolated from the silica gel plates. The lower R f component was further purified by preparative HPLC (Vydac C-18 column, acetonitrile-water (containing 0.1% trifluoroacetic acid), 8 mL/min flow rate,45 minute gradient) to give the title compound (8 mg) as a homogeneous white solid: m.p. 203°-204° C. (d). HPLC=99% pure at 214 nm, Rf=0.36(EtOAc:pyridine:HOAc:H 2 O; 10:5:1:3) NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 458 (M + +1). Analysis for C 25 H 23 N 5 O 4 •1.45 TFA•0.50 H 2 O: Calculated: C, 53.02; H, 4.06; N, 11.08. Found: C, 53.05; H, 4.11; N, 10.96.
EXAMPLE 11
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1 H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R,S)-tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea}
Part 1: 3-Amino-3-(3-nitrophenyl)propionamide (G)
An autoclave was charged with 1.5 g of methyl 3-nitrophenylcinnamate, 15 mL of liquid ammonia, and 15 mL of 2-propanol. The autoclave was sealed and heated at 150° C. for 15 hours. The autoclave was cooled, vented, and the contents were concentrated under reduced pressure. The residual material was flash chromatographed on silica gel (chloroform-methanol-concentrated ammonium hydroxide elution, 90:10:1 v/v) to yield 617 mg of the title compound.
Part 2: Methyl 3-Amino-3-(3-nitrophenyl)propionate (H)
3-Amino-3-(3-nitrophenyl)propionamide (822 mg) and 12.3 g of Bio-Rad AG-MP-50 resin were combined in 25 mL of methanol and the resulting mixture was heated to reflux according to the literature procedure (J. Org. Chem. (1981) 46, 5351-5353). The crude reaction product was purified by flash chromatography (ethyl acetate elution) to yield 405 mg of the title compound.
Part 3: Methyl 3-tert-Butyloxycarbonylamino-3-(3-aminophenyl)propionate (I)
Methyl 3-amino-3-(3-nitrophenyl)propionate (400 mg) was dissolved in 5 mL of methylene chloride and treated with di-tert-butyldicarbonate (428 mg). The reaction mixture was protected from moisture and stirred at room temperature for one hour. Additional amounts of di-tert-butyldicarbonate (100 mg) were added to the reaction mixture after 1 and 2 hours, respectively. Finally, 131 μL of triethylamine was added and stirring was continued for 30 minutes more. The volatiles were removed under reduced pressure and the residual material was passed through a silica gel column (hexane-ethyl acetate elution, 1:1 v/v) to yield 423 mg of methyl 3-tert-butyloxycarbonylamino-3-(3-nitrophenyl)propionate. 383 mg of the latter compound was hydrogenated at atmospheric pressure employing 100 mg of 10% palladium on carbon catalyst in 15 mL of methanol. After two hours the reaction mixture was concentrated and the residue was azeotropically dried with toluene to give 333 mg of the title compound.
Part 4: Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}N'-{[3-((1R,S)-tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl 3-tert-butyloxycarbonylamino-3-(3-aminophenyl)propionate (I) (333 mg) in 28 mL of tetrahydrofuran was reacted with 112 mg of triphosgene, 472 μL of triethylamine, and 300 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2-one in 15 mL of tetrahydrofuran. The crude reaction product was flash chromatographed on silica gel (ethyl acetate elution) to give the title compound (551 mg) as a mixture of diasteriomers. The analytical material was obtained as a solid by dissolving the chromatographed material in ethyl acetate and precipitating it with hexane: m.p. 149°-151° C. HPLC=99% pure at 214 nm; TLC R f =0.43 (CH 2 Cl 2 --CH 3 OH--HOAc,90:10:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 586 (M + +1). Analysis for C 32 H 35 N 5 O 6 •0.2 Hexane•1.35 EtOAc: Calculated: C, 61.91; H, 6.95; N, 9.35. Found: C, 61.90; H, 6.71; N, 9.35.
EXAMPLE 12
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N,-{[3-((1R,S)-amino-2-methoxycarbonyl)ethylphenyl]-urea}
Utilizing reaction conditions identical to those described in Example 2,303 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R,S)-tert-butyloxycarbonylamino-2-methoxycarbonyl)ethylphenyl]-urea} was converted to the title compound which was obtained as a solid after chromatography on silica gel (chloroform-methanol elution, 9:1 v/v); yield 205 mg: m.p. 160°-162° C. (d). HPLC=98% pure at 214 nm; TLC R f =0.25 (CH 2 Cl 2 --CH 3 OH--HOAc--H 2 O, 90:10:1:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. Analysis for C 26 H 25 N 5 O 4 •1.65 H 2 O: Calculated: C, 63.89; H, 6.03; N, 12.94. Found: C, 63.90; H, 6.19; N, 12.96.
EXAMPLE 13
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R,S)-amino- 2-carboxy)ethylphenyl]-urea}
Lithium hydroxide hydrate (9 mg) and 100 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[3-((1R,S)-amino-2methoxycarbonyl)ethylphenyl]-urea} were combined in 4 mL of a tetrahydrofuran-water mixture (1:1, v/v) and stirred at room temperature for two hours. An additional 5 mg of lithium hydroxide hydrate was added and stirring was continued for 60 minutes more. The solvent was roto-evaporated and the crude product was purified by preparative reverse phase HPLC (Vydac C-18 column, acetonitrile-water (containing 0.1% trifluoroacetic acid), 8 mL/min flow rate,45 minute gradient) to yield the title compound as a solid after lyophilization: m.p. 178° C. (d); (shrinks at 133° C.). HPLC=98% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 472 (M + +1). Analysis for C 26 H 25 N 5 O 4 •2.0 TFA•0.3 H 2 O: Calculated: C, 51.09; H, 3.94; N, 9.93. Found: C, 51.09; H, 3.63; N, 10.29.
EXAMPLE 14
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl }-N'-{[8-(methyl-2(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
Part 1: R,S-5'-Nitrospiro[imidazolidine-4,2'(1H)-3',4'-dihydronaphthalene]-2, 5-dione; R,S-6'-nitrospiro[imidazolidine-4,2'(1H)-3',4'-dihydronaphthalene]-2, 5-dione; R,S-7'-nitrospiro[imidazolidine-4,2'(1H)-3',440 -dihydronaphthalene]-2,5-dione; and R,S-8'-nitrospiro[imidazolidine-4,2,(1H)-3',4'-dihydronaphthalene]-2,5-dione
7,8-Benzo-1,3-diazaspiro[4,5]decane-2,4-dione (20 g) was nitrated with 200 mL of 70% nitric acid according to the literature procedure in J. Med. Chem. (1987) 30, 542-547. Work-up of the reaction mixture afforded 20 g of a yellow solid which was characterized as a mixture of all four possible regioisomeric nitro derivatives.
Part 2: R,S-7'-Nitrospiro[imidazolidine-1-ethyl-4,2'-(3H)-3',4'-dihydronaphthalene]-2,5-dione and R,S-8'-Nitrospiro[imidazolidine-1-ethyl-4,2,-(3H)-3',4'-dihydronaphthalene]-2,5-dione (Mixture L); R,S-5'-Nitrospiro[imidazolidine-4,2'(1H)-3',4'-dihydronaphthalene]-2,5-dione and R,S-6'-nitrospiro[imidazolidine-4,2'(1H)-3',4'-dihydronaphthalene]-2,5-dione (Mixture M)
Four grams of the mixture obtained in Part 1, Example 14 was dissolved in 15.3 mL of 1N sodium hydroxide solution. The clear solution was concentrated to dryness under reduced pressure to give a solid which was azeotropically dried with toluene. This material was then combined with 900 mg of potassium iodide, 8.5 mL of ethyl bromide in 125 mL of absolute ethanol and heated to reflux for five hours. The solvent and excess reagent were removed in vacuo and the residue was partitioned between ethyl acetate and water. The organic phase was washed with water and brine, then dried (Na 2 SO 4 ), and concentrated. The crude reaction product was then flash chromatographed on silica gel employing an ethyl acetate-hexane gradient (1:2 to 1:1 v/v) to yield 1.16 g of an chromatographically inseparable mixture of the title compounds, mixture L and 1.63 g of mixture M.
Part 3: Methyl 2-(R,S)-tert-Butyloxycarbonylamino-8-(amino-1,2,3,4-tetrahydro-2-naphthoate (0) and Methyl 2-(R,S)-tert-Butyloxycarbonylamino-7-(amino-1,2,3,4-tetrahydro-2-naphthoate (P)
Mixture L (400 mg) was combined with 10 mL of 12N hydrochloric acid and heated to 140° C. in a sealed tube for three days. Concentration of the reaction mixture afforded 335 mg of the corresponding amino acid hydrolyzation products. This material was dissolved in 2.22 mL of 1N sodium hydroxide solution and treated in succession with 266 mg of di-tert-butyl dicarbonate, 5 mL of water, and 5 mL of tert-butanol. The pH of the reaction mixture was adjusted to 8-8.5 with the addition of sodium hydroxide solution. After 1 hour, an additional 100 mg of di-tert-butyl dicarbonate was added and stirring was continued for 20 minutes more. The reaction mixture was washed with pentane, rendered acidic to pH 3 with potassium hydrogen sulfate, and extracted with ethyl acetate. The combined organic extracts were washed with brine, then dried (Na 2 SO 4 ), and concentrated to give the protected amino acids. This material (104 mg) was dissolved in 5 mL of N,N-dimethylformamide and treated with 10 equivalents of solid sodium bicarbonate and 97 μL (5 equivalents) of iodomethane. After stirring 90 minutes at room temperature, an additional 97 μL of iodomethane was added. The reaction mixture was filtered after one hour, concentrated and the residue was partitioned between ethyl acetate and water. The crude product was chromatographed on pre-coated silica gel plates (1 mm thickness, hexane-ethyl acetate elution, 1:1 v/v) to yield the protected methyl esters as a chromatographically inseparable mixture. This material (60 mg) was hydrogenated at atmospheric pressure in 5 mL of methanol in the presence of 30 mg of 10% on carbon palladium catalyst. After 60 minutes the reaction mixture was filtered and the mixture was purified by preparative thick layer chromatography on pro-coated silica gel plates (0.5 mm thickness, hexane-ethyl acetate elution, 1:1 v/v) to afford 15 mg of the title compound 0 and 33 mg of the title compound P.
Part4: Methyl 2-(R,S)-tert-Butyloxycarbonylamino-6-(amino-1,2,3,4-tetrahydro-2-naphthoate (Q) and Methyl 2-(R,S)-tert-Butyloxycarbonylamino-5-(amino-1,2,3,4-tetrahydro-2-naphthoate (R)
By employing reaction conditions identical to those described in Part 3, Example 14, mixture M (500 mg) was transformed in the prescribed manner to give 30 mg of title compound Q and 44 mg of title compound R.
Part 5: N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N,-{[8-(methyl-2-(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl 2-(R,S)-tert-butyloxycarbonylamino-8-(amino-1,2,3,4-tetrahydro-2-naphthoate (0) (15 mg) in 1 mL of tetrahydrofuran was reacted with 4.6 mg of triphosgene, 20 μL of triethylamine, and 14 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2-one. The crude reaction product was purified by preparative thick layer chromatography on pre-coated silica gel plates (0.5 mm thickness, chloroform-methanol elution, 9:1 v/v) to give the title compound as a mixture of diasteriomers: m.p. 185°-189° C. HPLC=97.7% pure at 214 run. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 612 (M + +1). Analysis for C 34 H 36 N 5 O 6 •0.5 H 2 O: Calculated: C, 65.90; H, 6.02; N, 11.30. Found: C, 65.93; H, 6.22; N, 11.14.
EXAMPLE 15
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl 2-(R,S)-tert-butyloxycarbonylamino-7-(amino-1,2,3,4-tetrahydro-2-naphthoate (P) (33 mg) in 2.5 mL of tetrahydrofuran was reacted with 10 mg of triphosgene, 43 μL of triethylamine, add 30 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2one. The crude reaction product was purified by preparative thick layer chromatography on pre-coated silica gel plates (0.5 mm thickness, chloroform-methanol elution, 9:1 v/v) to give 40 mg of the title compound as a mixture of diasteriomers: m.p. 181°-185° C. HPLC=>99% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 612 (M + +1). Analysis for C 34 H 36 N 5 O 6 •0.2 CHCl 3 : Calculated: C, 64.73; H, 5.75; N, 11.04. Found: C, 64.97; H, 6.07; N, 10.69.
EXAMPLE 16
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
Utilizing reaction conditions identical to those described in Example 2, 38 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R,S)-tert-butyloxy- carbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea} was converted to the title compound which was obtained as a solid: m.p. 213°-218° C. (d). HPLC=99% pure at 214 nm; TLC R f =0.52 (CHCl 3 --CH 3 OH--NH 4 OH, 90:10:1). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 512 (M+1). Analysis for C 29 H 29 N 5 O 4 •2.6 H 2 O•1.0 HCl•0.6 CHCl 3 : Calculated: C, 56.43; H, 5.57; N, 11.12. Found: C, 56.45; H, 5.60; N, 10.76.
EXAMPLE 17
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7 -(2-(R,S)amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea}
Utilizing reaction conditions identical to those described in Example 6, 37 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[7-(methyl-2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea} was converted to the title compound which was obtained as a solid after preparative HPLC chromatography: m.p. 199° C. (d). HPLC=>94% pure at 214 nm; TLC R f =0.67 (EtOAc-pyridine-HOAc--H 2 O, 10:5:1:3 v/v). NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 498 (M+1). Analysis for C 28 H 27 N 5 O 4 •1.25 H 2 O •1.0 TFA: Calculated: C, 56.83; H, 4.85; N, 11.04. Found: C, 56.80; H, 4.84; N, 10.67.
EXAMPLE 18
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(methyl-2-(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl 2-(R,S)-tert-butyloxycarbonylamino-6-(amino-1,2,3,4-tetrahydro-2-naphthoate (Q) (30 mg) in 2.0 mL of tetrahydrofuran was reacted with 10 mg of triphosgene, 39 μL of triethylamine, and 27 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2one. The crude reaction product was purified by preparative thick layer chromatography on pre-coated silica gel plates (1.0 nun thickness, chloroform-methanol elution, 9:1 v/v) to give 36 mg of the title compound as a mixture of diasteriomers:.m.p. 173°-178° C. HPLC=99% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 612 (M + +1). Analysis for C 34 H 36 N 5 O 6 •0.7 H 2 O: Calculated: C, 65.41; H, 6.20; N, 11.22. Found: C, 65.44; H, 6.08; N, 10.90.
EXAMPLE 19
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(methyl-2-R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
Utilizing reaction conditions identical to those described in Example 2, 30 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl -1H-1,4-benzodiazepin-3-yl}-N,-{[6-(methyl-2-(R,S)-tert-butyloxycarbonyl- amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea} was converted to the title compound which was obtained as a solid. HPLC=>99% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 512 (M+1).
EXAMPLE 20
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl }-N'-{[6-(2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea}
Utilizing reaction conditions identical to those described in Example 6, 27 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[6-(methyl-2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate) ]-urea} was converted to the title compound which was obtained as a solid after preparative HPLC chromatography: m.p. 196° C. (d). HPLC=>99% pure at 214 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 498 (M+1). Analysis for C 28 H 27 N 5 O 4 •1.55 H 2 O •0.85 TFA: Calculated: C, 54.17; H, 4.42; N, 10.16. Found: C, 54.17; H, 4.40; N, 10.27.
EXAMPLE 21
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(methyl-2-(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
By employing reaction conditions identical to those in Example 1, Part 3, a solution of methyl 2-(R,S)-tert-butyloxycarbonylamino-5-(amino-1,2,3,4-tetrahydro-2-naphthoate (R) (4 mg) in 3.0 mL of tetrahydrofuran was reacted with 14 mg of triphosgene, 57 μL of triethylamine, and 40 mg of 1,3-dihydro-1-methyl-3(R)-amino-5-phenyl-2H-1,4-benzodiazepin-2one. The crude reaction product was purified by preparative thick layer chromatography on pre-coated silica gel plates (1.0 mm thickness, chloroform-methanol elution, 9:1 v/v) to give 54 mg of the title compound as a mixture of diasteriomers: m.p. 171°-175° C. HPLC=99% pure at 214 rim. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 612 (M + +1). Analysis for C 34 H 36 N 5 O 6 •0.25 H 2 O •0.8CHCl 3 : Calculated: C, 58.73; H, 5.42; N, 9.84. Found: C, 58.73; H, 5.45; N, 9.87.
EXAMPLE 22
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(methyl-2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea}
Utilizing reaction conditions identical to those described in Example 2, 49 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H -1,4-benzodiazepin-3-yl}-N,-{[5-(methyl-2-(R,S)-tert-butyloxycarbonylamino-1,2,3,4-tetrahydro-2-naphthoate)]-urea} was converted to the title compound which was obtained as a solid. HPLC=99% pure at 210 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 512 (M+1). Analysis for C 29 H 29 N 5 O 4 •2.7 H 2 O •2.0 HCl •0.6 EtOAc: Calculated: C, 54.98; H, 6.05; N, 10.21. Found: C, 54.99; H, 5.66; N, 10.13.
EXAMPLE 23
Synthesis of N-{(3R)-1,3-Dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoic acid)]-urea}
Utilizing reaction conditions identical to those described in Example 6, 46 mg of N-{(3R)-1,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl}-N'-{[5-(methyl-2-(R,S)-amino-1,2,3,4-tetrahydro-2-naphthoate)]-urea} was converted to the title compound which was obtained as a solid after preparative HPLC chromatography: m.p. 189° C. (d). HPLC=>99% pure at 210 nm. NMR(DMSO-d 6 ): Consistent with structure assignment and confirms presence of solvent. FAB MS: 498 (M+1). Analysis for C 28 H 27 N 5 O 4 •0.95 H 2 O •1.9 TFA: Calculated: C, 52.23; H, 4.25; N, 9.58. Found: C, 52.24; H, 4.24; N, 9.87.
|
Benzodiazepine analogs of the formula: ##STR1## are disclosed which are antagonists of gastrin and cholecystokinin (CCK).
| 0
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a pyrolysis process for treating sewage sludge, more particularly a pyrolysis process for sewage sludge which reduces the formation of harmful hexavalent chromium even if the sewage contains chromium.
2. Description of the Prior Art
The sewage sludge formed by treating sewage is generally dehydrated by adding a dehydrating agent, such as ferric chloride or calcium hydroxide and then incinerated at a temperature of 800°-900° C. under an oxidizing atmosphere and finally discharged as an incinerated ash for reclamation. However, when the sewage sludge contains chromium, trivalent chromium in the sludge is oxidized into harmful water soluble hexavalent chromium in the course of incinerating, so that if such an incinerated ash is discharged from reclamation, the harmful hexavalent chromium in the incinerated ash is released into underground water, rivers and the like by rain water, which constitutes a risk of environmental pollution. Therefore, in the incinerated ash containing hexavalent chromium, a post-treatment for preventing harm of hexavalent chromium is necessary. For this purpose, the incinerated ash is solidified into concrete by using cement, the hexavalent chromium in the incinerated ash is reduced by adding a reducing agent or the incinerated ash is fused and solidified at a high temperature of 1,300°-1,500° C., but such processes are complicated in the treating step and there is fear that secondary pollution is caused and furthermore these processes become commercially expensive.
An internal heating type or an external heating type of pyrolysis process, in which thermally decomposed gas of sewage sludge is not burned in a pyrolysis furnace, has been recently proposed. In these pyrolysis processes, the formation of hexavalent chromium can be reduced but the sewage sludge is treated only by the thermal decomposition, so that the treating capacity per unit time is small and a large amount of fuel for generating hot gas is needed and further tar contained in the exhaust gas discharged from the pyrolysis furnace deposits on pipes and instruments and trouble often occurs in view of the operation.
SUMMARY OF THE INVENTION
A main object of the present invention is to improve a pyrolysis process for treating sewage sludge containing chromium and to prevent environmental pollution.
Another object of the present invention is to provide a pyrolysis process for treating sewage sludge, by which the formation of hexavalent chromium is reduced.
A further object of the present invention is to provide a pyrolysis process for treating sewage sludge containing chromium by which the treating capacity is improved and the amount of fuel needed is decreased.
The other object of the present invention is to improve conventional incineration processes and pyrolysis processes for treating the sewage sludge containing chromium.
BRIEF DESCRIPTION OF THE DRAWING
The attached drawing is a view for explaining an embodiment of the process of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The invention will be explained in more detail with reference to the drawing. A dehydrated cake 1 of a sewage sludge containing chromium and having a water content of 65-80% or a dehydrated cake 1 in which the water content is reduced to about 10-50% by a preliminary drying, is charged from an upper portion of a vertical multi-hearth pyrolysis furnace 2.
The vertical multi-hearth pyrolysis furnace 2 is provided with a plurality of openings for supplying oxygen of less than the theoretical amount necessary for burning the sewage sludge into the furnace and a plurality of openings for supplying a hot gas containing no oxygen into the furnace. The dehydrated cake 1 fed into the vertical multi-hearth pyrolysis furnace 2 is heated to 700°-900° C. by the hot gas containing no oxygen supplied from the openings 4 and pyrolyzed while descending in the furnace to form a combustible thermally decomposed gas and the formed combustible decomposed gas is burned by a slight amount of oxygen supplied from the openings 3, which is controlled by an apparatus 5 for measuring the partial pressure of oxygen in the furnace always to keep said partial pressure substantially at zero. The amount of oxygen supplied must be less than the theoretical amount necessary for burning the sewage sludge and said amount is preferred to be less than 90% of the theoretical amount, more preferably 45-75%.
The raising of the temperature in the furnace due to the partial combustion of the decomposed gas is measured by an apparatus 6 for measuring temperature in the furnace and the amount of the hot gas supplied from the openings 4 is controlled by the indication of said apparatus 6.
The dehydrated cake 1 stays for 10-50 minutes in the furnace and is completely pyrolyzed and the exhaust gas containing the combustible gas is discharged from an opening 7 provided at the top of the furnace and the pyrolyzed residue is discharged from the bottom 8 of the furnace into water and quenched therein. The exhaust gas containing the combustible gas is burned in a combustion chamber 9 and is utilized as a heat source.
Since the partial pressure of oxygen in the furnace is kept substantially in zero, oxygen supplied from the opening 3 is consumed only for the partial combustion of the thermally decomposed gas and does not diffuse into the surface and the inner portion of the sludge to be pyrolyzed, so that trivalent chromium in the sludge is not substantially oxidized into hexavalent chromium. However, when the partial pressure of oxygen in the furnace is not zero but an oxidizing atmosphere is formed, oxygen diffuses from the surface of the sludge to be pyrolyzed into the inner portion and trivalent chromium in the sludge is oxidized into hexavalent chromium and therefore the harmful hexavalent chromium remains in the pyrolyzed residue. Accordingly, in order to reduce the formation of hexavalent chromium, the partial pressure of oxygen in the furnace must be always kept substantially at zero in any portion. When the pyrolyzed residue is contacted with air at a temperature higher than 150° C., the formation of hexavalent chromium increases, so that even when the pyrolyzed residue is cooled in air, it is preferred to cool said residue under a state where oxygen is not present but, in general, it is preferred to quench said residue in water.
By controlling the amount of oxygen supplied so that the concentration of carbon monoxide in the furnace is 1-5% by volume, the partial pressure of oxygen in the furnace also can be kept substantially at zero. As the pyrolysis furnace for the present invention, use may be made of a rotary kiln, a fluidized bed furnace and pyrolysis furnaces other than the above described vertical multi-hearth pyrolysis furnace.
The following example is given for the purpose of illustration of this invention and is not intended as any limitation thereof.
EXAMPLE
Dehydrated cake 1 of sewage sludge containing 0.1% by weight of trivalent chromium was preliminarily dried to an average water content of 30% and supplied into the vertical multi-hearth pyrolysis furnace 2 as shown in the attached drawing at a feeding rate of 2,100 Kg/hr. and subjected to pyrolysis for 20 minutes in the furnace heated at 800° C. by hot gas containing no oxygen obtained by burning heavy oil at air ratio of 0.95. Oxygen corresponding to 70% of the theoretical amount of oxygen necessary for burning the sewage sludge was supplied from the opening 3 to each stage to keep the partial pressure of oxygen in each hearth substantially at zero to burn the thermally decomposed gas and simultaneously to effect pyrolysis and then the pyrolyzed residue was discharged from the furnace bottom 8 into water without contacting with air to quench the pyrolyzed residue, whereby the pyrolyzed residue No. 1 according to the present invention was obtained.
For comparison, the same sewage sludge as described above was completely incinerated at 850° C. in a conventional incineration process wherein the concentration of oxygen in the furnace was 10% by volume by supplying oxygen of 1.5 times the theoretical amount of oxygen necessary for incinerating the sewage sludge to the furnace, to obtain an incinerated ash No. 4.
Furthermore, the same sewage sludge as described above was treated with an internal heating type pyrolysis process under a state where oxygen is not present, at 800° C. by supplying a hot gas containing no oxygen to obtain a pyrolyzed residue No. 2. Furthermore, the same sewage sludge was treated with an external heating type non-combustion pyrolysis process by using a rotary kiln type non-combustion pyrolysis furnace to obtain a pyrolyzed residue No. 3. The comparison of these treating processes is shown in the following Table 1.
Table 1__________________________________________________________________________ No. 1 No. 2 No. 3 No. 4__________________________________________________________________________ Present Invention Conventional Conventional Conventional__________________________________________________________________________ Internal heating Internal heating External heating type partial type non- type non- combustion combustion combustion Incineration pyrolysis process pyrolysis process pyrolysis process process__________________________________________________________________________ External heating Vertical 6-hearth Vertial 6-hearth type rotary kiln Vertical 6-hearth (Total area of (Total area of (Total surface (Total area of furnace bed) furnace bed) area of kiln) furnace bed)Treating apparatus 50 m.sup.2 50 m.sup.2 50 m.sup.2 50 m.sup.2Treating capacity(Kg dried cake/H) 2,100 1,200 900 2,300Ig.Loss of the residueor the incineratedash (%) 5.0 5.1 5.4 2.5Formed amount ofhexavalent chromium(mg/Kg) 1.4 1.0 1.1 510Concentration ofhexavalent chromiumdissolved off (mg/l) <0.1 <0.1 <0.1 18.4Trouble of deposit oftar on pipes andinstruments Substantially no much much Absolutely noOil consumption (Kg/H) 90 310 400 30__________________________________________________________________________
As seen from the above Table 1, the pyrolysis process of the present invention can provide a treating capacity of 2 times that of the conventional pyrolysis processes and is substantially equal to the treating capacity of the conventional incineration process. The formed amount of hexavalent chromium in the pyrolyzed residue according to the present invention is less than 1/200 of that of the conventional incineration process. The fuel amount for generating the hot gas necessary for the pyrolysis process in the present invention is less than 1/3 that of the conventional pyrolysis processes. The deposit and clogging of pipes due to formation of tar, which have been observed in the conventional pyrolysis processes, were not caused.
As mentioned above, the method for pyrolyzing sewage sludge according to the present invention can noticeably reduce the formation of hexavalant chromium as compared with the conventional incineration process. As compared with the conventional pyrolysis processes, the pyrolysis process of the present invention is larger in the treating capacity per unit time, although the used fuel is far smaller and the clogging of pipes and the deposit on instruments due to tar in the exhaust gas are not substantially caused. Accordingly, the pyrolysis process for treating sewage sludge according to the present invention is very useful.
|
A pyrolysis process for treating sewage sludge containing chromium by burning combustible gas produced by thermal decomposition of the sewage sludge in a pyrolysis furnace by supplying oxygen of less than the theoretical amount necessary for burning the sewage sludge and keeping a partial pressure of oxygen in the furnace substantially at zero reduces the amount of hexavalent chromium remaining in the pyrolyzed residue to a harmless degree, and does not pollute the environment, has a large treating capacity, and is small in the necessary amount of fuel.
| 2
|
FIELD OF THE INVENTION
The invention comprises an injection device for medical and veterinary use, having a single-use stabilizing sight which actuates a means serving as a safety valve at the level of the needle.
This apparatus is intended to perform intradermic, subcutaneous or intramuscular injections for medical or veterinary use, and more particularly in mesotherapy, hydropuncture, vaccinations or allergological tests.
1. The Known Prior Art
The state of the art may be defined by French patent 2,524,321, of the same author. This patent describes a "manual or mechanical" injection device for medical and veterinary use. This patent describes an injection device which comprises: a support stock having the form of a revolver, a removable injection syringe provided with a syringe piston, a single injection needle or a multi-injector bearing several injection needles, a syringe cradle integrating the syringe with the support stock, means for positioning the impact and predetermining the degree of penetration of the needle or needles, mechanical transmission means comprising a ratchet and a barrel transmitting the exerted thrust, to enable penetration of the needle or needles and injection of the liquid.
The state of the art may also be defined by a patent such as HALLER, U.S. Pat. No. 4,198,975 and LUCIANO, U.S. Pat. No. 3,790,048.
These patents describe in particular pistols for making punctures, one of which pistols is electric, namely that described in the LUCIANO patent, whereas the other is completely mechanical, namely that described in the HALLER patent. Another patent is capable of defining the state of the art, namely French patent FR.B2.2.390.175.
This patent FR.B2.2.390.175 describes a process for mesotherapy treatment and its injection device forming a micro-injector which is automatic as regards application.
2. Background of the Invention
Problems associated with rapidly-spreading contagious diseases require a revision of this type of pistol for medical and veterinary use. For medical use, this type of pistol is especially used in mesotherapy. It is important that all of the parts of the injection device which contact the patient to be treated be of the single-use type.
Another problem occurs as a practical matter with this type of injection device such as defined by the state of the art. The pressure exerted by the piston on the syringe creates a certain inertia due to overpressure, which implies that at each exit of the needle from the skin, there is a loss of liquid. Droplets spill out, which is disagreeable for the patient as well as for the person using the injection device. This leakage of liquid also represents, in the case where the injected liquid is relatively expensive, a significant loss of money.
Finally, in the case of specific treatment such as treatment of cellulite, the user of the device must actuate the trigger 4 to 600 times so that the said device injects the liquid. After several treatments, fatigue results from using the mechanical devices now on the market.
The invention tends to solve all of these problems.
SUMMARY OF THE INVENTION
The device according to the invention is an injection device of the electric type comprising a support stock, a syringe received on the upper horizontal surface of the support stock and maintained forwardly by its tip which rests on a stirrup and rearwardly by the head of the piston of the syringe which is housed in a movable slide actuated by an electric motor which transmits the thrust for enabling penetration of the needle and injection of the liquid, a stabilizing sight of the skin guides and predetermines the degree of penetration of the needle by an adjustment.
The stabilizing sight is of the removable type, a means serving as a spring assures its maintenance in a hollow micrometer screw itself housed in a movable cylinder; the said movable cylinder comprising a movable finger which acts on a means serving as a safety valve disposed at the level of the injection needle.
The head of the piston for the syringe is in contact with the head of a piston situated in the movable slide, the piston is provided with a spring mounted coaxially with the rod of the piston; the said spring is housed in the movable slide, the cursor and piston assembly is actuated by the electric motor which acts on a threaded shaft on which is mounted the body of the slide which forms, at this level, a manipulating screw.
The head of the piston is in meshing engagement with the manipulating screw via a threaded shaft whose end rests on a bearing situated in the support stock and whose other end terminates in a toothed pinion which meshes with a toothed pinion situated at the output of a reducer disposed in extension of the electric motor.
In the electric and electronic embodiment, the motor may be a stepping motor; the motor meshes, via its shaft and its toothed wheel, with another wheel directly geared to the threaded shaft; on the threaded shaft is mounted a slide which is geared with the head of the piston of the syringe.
An operating commutator is disposed in extension of the shaft of the chamber and of the cylinder which houses the stabilizing site, this operating commutator assures the enabling of the automatic operation, continuous or simultaneous, through the action of the sight which latter is in contact with the skin;
forward progress contact;
rearward progress contact;
forward interrupter;
rear interrupter;
start/stop contact.
The device is provided with a signal, which is a sound signal, which is emitted at each injection.
The stabilizing sight extends via its end into an orifice of the anterior portion of the support stock; this end is housed in a hollow micrometer screw; the said hollow micrometer screw is threaded on its exterior face so as to be able to be displaced in a chamber of a movable cylinder provided to this end; the said movable cylinder is terminated by a shaft; the said shaft penetrates in a bearing, fixed to the support stock; a return spring is disposed coaxially to the said shaft between the chamber and the end of its shaft; an adjusting knob permits the shaft and the chamber to return; the said chamber of the movable cylinder comprises a screw threading in its interior body; the screw threading corresponds to the threading on the exterior face of the micrometer screw; by turning the adjusting knob, the axis of the chamber turns whereas the micrometer screw is displaced in the said chamber of the movable cylinder; this adjusting knob thus permits adjusting the depth of entry of the end of the sight and thus regulates the degree of penetration of the needle into the skin.
The stabilizing sight is terminated by its end which is cruciform and which penetrates in the body of the cylinder which is slit along its longitudinal axis and solely in its anterior portion, whereas a retaining means is positioned about the body of the cylinder to serve as a fixing spring.
The retaining means is a retaining ring which is positioned around the body of the hollow micrometer screw.
The device is provided with a means acting as a safety valve, disposed at the level of the injection needle, the said safety valve being associated with a means acting as a detector of penetration of the needle into the skin.
The body of the mounting for the safety valve is disposed between the fixation end of the needle and the end of the syringe where the needle is conventionally encased.
The body of the mounting for the safety valve is provided with a means acting as a lever, which is actuated by a movable finger; the said movable finger is screwed on the anterior end of the chamber of the movable cylinder; the hollow micrometer screw may also be threaded at this level and comprise a stopping abutment; the movable finger is exterior whereas its body is cylindrical so as to fit between the chamber of the movable cylinder and the micrometer screw; the said body of the mounting for the safety valve is thus controlled by a means which acts as a detector of penetration of the needle into the skin; when the needle is withdrawn from the skin, the safety valve closes the opening of the body of the mounting for the safety valve which closes the passage of liquid from the syringe to the needle through the said opening.
The means acting as a detector of penetration of the needle into the skin is a lever, the said lever acts at the level of the wall of the body of the mounting for the safety valve; the said wall is, at this level, slightly thinner; the said lever thus acts directly on the safety valve which is freely mounted in the chamber, which allows a tilting which disengages the said safety valve from the opening, which permits circulation of liquid between the syringe and the needle.
The chamber of the body of the mounting for the safety valve may comprise pins which permit force-fitting the safety valve in the said chamber, but prevent this latter from exiting therefrom.
The safety valve has a frusto-conical shape.
BRIEF DESCRIPTION OF THE DRAWINGS
The attached drawings are given by way of explanatory and non-limiting example. They show a preferred embodiment according to the invention. They will permit ready understanding of the invention.
FIG. 1 is a sectional view of the injection device for medical and veterinary use, which displays the principal active members of the said device.
FIG. 1A is an enlarged fragment of FIG. 1, showing the means for securing the sight in the pistol.
FIG. 2 is a sectional view of the body of the mounting for the safety valve in closed position.
FIG. 3 is a sectional view showing the body of the mounting for the safety valve, its movable safety valve and the action of the lever which acts in the direction indicated by the arrows.
FIG. 4 is a sectional view of the injection device adapted for electric energization by rechargeable or non-rechargeable batteries or cells.
FIG. 5 is a schematic view of the injection device according to the invention, according to an electric or electronic embodiment.
FIG. 6 is a schematic view of the device according to the invention, according to another embodiment.
FIG. 7 is a sectional view along the line A--A of FIG. 6, of the support stock of the device showing the stirrup and the cruciform opening for the end of the stabilizing sight. In this embodiment the assembly is of single piece construction, formed by injection.
DETAILED DESCRIPTION OF THE INVENTION
The device according to the invention is an electric injection pistol. It comprises a support stock 1 having the form of a revolver. In its upper portion, and perpendicular to the handle 2 of the support stock 1, is disposed forwardly a stirrup 3 and rearwardly a movable slide 6. The syringe 4 is maintained at the level of its tip by the stirrup 3 on which the said tip rests and rearwardly by its piston 5 which is housed in a slide 6. The piston 5 of the syringe 4 is actuated by a piston 7 housed in the slide 6 whose rod is provided coaxially with a spring 8. The body of the slide 6 forms a manipulating screw 45, the said manipulating screw 45 of the movable slide 6 is in mesh with a threaded shaft 10 having an extremity 11 received in a bearing 12 situated in the support stock 1, and whose other extremity 13 terminates in a toothed pinion 14 which meshes with another toothed pinion 15 situated at the output of a reducer disposed in extension of the electric motor 17.
According to a preferred embodiment, the motor 17 and the reducer 16 are disposed in the handle 2 of the support stock 1.
The various operating contacts and commutators are as follows:
an operating commutator 18 is disposed in extension of the axis of the movable cylinder which houses the stabilizing sight, this operating commutator 18 assures the enabling of the automatic, continuous or simultaneous function, by action of the sight when this latter is in contact with the skin (this operating commutator may be a simple mechanical contact, or for example an optical detector);
19 is the forward progress contact;
20 is the rearward progress contact;
21, disposed in extension of the head 9 of the piston 7, is the forward interrupter;
22, integrated with the slide 6, is the rearward interrupter;
23 is the start/stop contact.
The device may be provided with a signal 44, which may be a sound signal or light signal.
In the embodiment shown, the said signal is a sound signal, as it may be interesting for the user to know the number of injections effected. Certain devices comprise counters which are difficult to read while manipulating the injection device. Other devices comprise display screens with light-emitting diodes which have the same disadvantage as a numerical counter.
The audible or luminous signal according to the invention has the advantage of familiarizing the practitioner with a rhythm, for example sound, which corresponds to a quantity of liquid in cubic millimeters, injected into the patient.
Without counting in a precise manner the number of injections, by the simple cadence and the elapsed time, the user knows that he has injected the necessary and sufficient quantity of liquid. The body of the slide 6 is extended beyond the axis of the syringe 4 so as to serve as a manipulating screw 45 with the threaded shaft 10.
As indicated in the preface of the invention, the stabilizing sight 24 is of the single-use type, which thus prevents problems due to contagious diseases.
The stabilizing sight 24 penetrates via its extremity 25 into an opening 26 of the anterior part of the support stock 1. This extremity 25 is housed in a hollow micrometer screw 46 whose exterior parts are threaded (see FIG. 1). The said micrometer screw 46 is threaded on its exterior surface so as to be able to be displaced in the chamber 27 of a movable cylinder 56 provided to this end. The said chamber 27 of the movable cylinder 56 is terminated by a shaft 28. The said shaft 28 is received in a bearing 29, integrated with the support stock. A return spring 54 is disposed coaxially with the said shaft 28 between the chamber 27 of the movable cylinder 56 and the end of its shaft 28. An adjusting knob 30 permits turning the shaft 28 and the chamber 27 of the movable cylinder 56. The said chamber 27 of the movable cylinder 56 comprises a screw threading in its interior body. The screw threading corresponds to the threading of the micrometer screw 46. By causing the adjusting knob 30 to turn, the shaft 28 and the chamber 27 of the movable cylinder 56 turn whereas the micrometer screw 46 is displaced in the said chamber 27 of the movable cylinder 56. This adjusting knob 30 thus permits adjusting the depth of entry of the extremity 25 of the sight 24 and thus adjusting the degree of penetration of the needle 31 in the skin. The said knob 30 thus adjusts the course of the stabilizing sight 24 and for guiding thus serves at the same time as a means for adjusting the penetration of the needle 31 in the skin. The assembly of the movable cylinder 56 and hollow micrometer screw 46 is maintained in the body of the support stock by a hollow threaded bolt 55 which permits the extremity 25 to extend from the stabilizing sight 24.
The stabilizing sight 24 is terminated at its extremity 25 which is cruciform and which penetrates into the cylindrical body 46 which is slit along its longitudinal axis and solely in its anterior portion whereas a retaining means 34 is positioned so as to assure the fixation of this extremity 25.
According to the embodiment of FIG. 1, the retaining means is a retaining ring 34 which is positioned around the body of the hollow micrometer screw 46.
The stabilizing sight 24 is thus removable, and may be securely received in or removed from its housing; it is thus adapted for a single use, and is disposable.
One of the characteristics of the invention resides in the fact that the injection device is provided with a means 35 acting as a safety valve disposed at the level of the injection needle 4.
This device acting as a safety valve prevents the problems of leakage of the injection fluid.
A mounting body for the safety valve 36 is disposed between the fixation cap 37 of the needle and the cap 38 of the syringe where the needle would conventionally be received.
The said mounting body for the safety valve 36 is provided with a means acting as a lever 39 which is actuated by a movable finger 40. The said movable finger 40 is screwed on the anterior end of the chamber 27 of the movable cylinder 56. To this end, the micrometer screw 46 may also be threaded at this level and comprise a stopping abutment 48. The movable finger 40 is exterior, whereas its body is cylindrical so as to be received between the chamber 27 of the movable cylinder 56 and the micrometer screw 46.
The said mounting body for the safety valve 36 is thus controlled by a means acting as a penetration detector for the needle 31 into the skin. When the needle 31 is withdrawn from the skin, the safety valve 35 closes the opening of the body of the mounting for the valve 36, which blocks the passage of liquid from the syringe 4 toward the needle 31 through the said opening.
The means acting as lever 39 is a detector of penetration of the needle into the skin. The said lever 39 acts directly on the wall 42 of the body of the mounting for the safety valve 36. The said wall 42 is, at this level, slightly thinner. The said lever 39 thus acts directly on the safety valve 35. The safety valve 35 is disengaged from the opening 41 which permits circulation of liquid between the syringe 4 and the needle 31. The constitution of the body of the mounting for the safety valve 36 may be of plastic whose performance characteristics are especially those known as "memory plastic" which resumes its shape after actuation of the lever 39 on the flexible wall 42, such that the said lever 39 may deform the said wall and act interiorly of the chamber 47 on the valve 35. The chamber 47 of the body of the mounting for safety valve 36 may comprise pins 43 which permit force-fitting the valve 35 in the said chamber 47, but prevent this latter from exiting therefrom. The said valve 35 is thus freely mounted in the chamber 47.
So as to be able to generate and regulate the injection pressure, the rod of the piston is terminated exteriorly of the piston by a threaded orifice 54 in which is received a screw 55 whose head is exterior to the slide 6. Action on the screw 55 permits adjusting the pressure of the spring 8 which is housed in the chamber of the slide 6. Adjustment of the tension of the spring 8 permits adjusting the injection pressure or power.
According to a preferred embodiment, the valve 35 has a frusto-conical shape, whose top is directed toward the syringe 4 and whose base closes the opening 41 of the chamber 47. The valve 35 may have a frusto-conical shape which facilitates the rocking and disengagement from the orifice 41 under the action of the lever 39.
FIG. 4 shows another electric and electronic embodiment, which permits a choice of programs for injection as a function of the diseases to be treated and of the choice of the apparatus based on the medicine. The motor 50 may in this case be a stepping motor and the power mechanism at the level of the piston of the syringe may be different. In the case shown in FIG. 4, the motor 50 meshes via its shaft and its toothed wheel 51, with another wheel 52 directly geared with the threaded shaft lo. On the threaded shaft 10 is mounted a slide 53 which engages with the head of the piston 5 of the syringe 4.
REFERENCES 1. Support stock 2. Handle 3. Stirrup 4. Syringe 5. Piston 6. Movable slide 7. Piston 8. Return spring 9. Piston head 10. Threaded shaft 11. Extremity of the shaft 12. Bearing 13. Extremity of the shaft 14. Toothed pinion 15. Toothed pinion 16. Reducer 17. Electric motor 18. Operating commutator 19. Forward travel contact 20. Rearward travel contact 21. Forward interrupter 22. Rear interrupter 23. Start/stop contact 24. Stabilizing sight 25. Extremity of the stabilizing sight 26. Orifice 27. Chamber of the movable cylinder 28. Shaft 29. Bearing 30. Knob 31. Needle 34. Retaining ring 35. Valve 36. Body of the support for the valve 37. Fixation cap for the needle 38. Cap for the syringe 39. Lever 40. Movable finger 41. Orifice 42. Flexible wall 43. Pins 44. Sound signal 45. Manipulating screw 46. Hollow micrometer screw receiving the extremity 25 of the stabilizing sight 24 47. Chamber of the body of the safety valve 48. Stoppage abutment situated on the exterior face of the micrometer screw 49. Cells or batteries 50. Electric stepping motor 51. Toothed wheel of the second embodiment 52. Wheel of the second embodiment 53. Slide of the second embodiment 54. Return spring 55. Hollow threaded bolt 56. Movable cylinder
|
An injection device comprising a support stock that supports a syringe having a plunger and a needle. The plunger is movable in an axial direction to force liquid from the syringe through the needle. A safety valve prevents flow of liquid from the syringe to the needle. A stabilizing sight is provided, for application against skin during an injection. The stabilizing sight is mounted on the device for movement relative to the device such that when the device is pressed against the skin the needle moves from a retracted position relative to the stabilizing sight to an advanced position relative to the stabilizing sight to penetrate the skin. The stabilizing sight is interconnected with the safety valve in such a way that when the needle is in that advanced position the safety valve is moved to an open position and when the needle is in that retracted position the safety valve is in a closed position.
| 0
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a capping apparatus for capping containers, such as bottles, and, in particular, to a constant-torque capping apparatus capable of capping a container at a predetermined tightening torque accurately at all times. This invention is related to U.S. Pat. No. 4,535,583 issued Aug. 20, 1985, entitled "Rotary Type Capping Apparatus".
2. Description of the Prior Art
Typically, a prior art capping apparatus includes a turn table having a plurality of container holders disposed along the periphery of the turn table and a plurality of capping heads which are each provided corresponding in position to the container holders and driven to move along a circular path together with the turn table. Each of the capping heads has a cap holder which releasably holds a cap at its bottom and which is driven to rotate so as to have the cap screwed onto the mouth of the container held by the corresponding container holder on the turn table. In such a prior art capping apparatus, a sun gear is commonly provided as fixed in position and coaxial with a rotary shaft of the turn table and a plurality of pinions are provided in mesh with and disposed around the sun gear. Each of the pinions is fixedly provided on a driving shaft which is operatively connected to the corresponding cap holder so that the cap holder may be driven to rotate when the corresponding pinion moves around the sun gear in mesh therewith, thereby causing the cap held by the cap holder to be screwed onto the mouth of the corresponding container. In this prior art structure, a clutch is typically provided in a power transmitting system between the pinion and the cap holder and a slippage is induced in the clutch when the cap tightening force has reached a predetermined value.
However, in such a prior art capping apparatus, since the rotation of each pinion around its own axis depends on the rotation of the turn table, a torque for screwing a cap onto a container is directly determined by the rotation of the turn table. As a result, if the rotation of the turn table varies for some reason, the screwing or tightening torque also varies accordingly. This has been found to be extremely disadvantageous because the rotational speed of the turn table is sometimes desired to be set at different levels to accomodate other processing stations in the same container handling line, such as a filling station where desired contents are filled in the containers and a labelling station where labels are glued onto the containers. Moreover, even if the capping apparatus itself is operated at constant speed, the magnitude of inertia torque applied to the cap at the final stage of the capping operation tends to fluctuate for various reasons so that there has been encountered a difficulty in maintaining the cap tightening torque at a constant value with high accuracy.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to obviate the above-described disadvantages of the prior art and to provide an improved capping apparatus.
Another object of the present invention is to provide an improved capping apparatus capable of capping containers, such as bottles, at predetermined tightening torque at high accuracy at all times.
A still further object of the present invention is to provide an improved capping apparatus for having caps tightly screwed onto the mouth of containers at constant tightening torque one after another in a continuous manner.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration showing the general flow of containers which are uncapped when supplied into a capping apparatus of the present invention and which are capped when discharged out of the capping apparatus;
FIG. 2 is a schematic illustration showing partly in cross-section the overall structure of the capping apparatus constructed in accordance with one embodiment of the present invention;
FIG. 3 is a schematic illustration showing the detailed structure of one of the capping heads of the capping apparatus shown in FIG. 2; and
FIG. 4 is a timing chart which is useful for explaining the operation of the present capping apparatus shown in FIGS. 2 and 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1, a capping apparatus 1 of the present invention receives containers 3 (see FIG. 2), such as bottles, as supplied from a transporting conveyor 2 via an inlet star wheel 4, and after having been capped within the capping apparatus 1, the containers 3 are discharged to another transporting conveyor 6 through an outlet star wheel 5. The detailed structure of these star wheels may be found in copending U.S. patent application, Ser. No. 06/537,465, which is also assigned to the assignee of this application and which is incorporated herein by reference.
As illustrated in FIG. 2, the capping apparatus includes a fixed shaft 7 which extends vertically from a base of the apparatus, and a rotary cylinder 8 which is rotatably fitted onto the fixed shaft 7 from above. The rotary shaft 8 is operatively coupled to a motor 9, which is fixedly mounted on the base of the apparatus, and, thus, the rotary cylinder 8 may be driven to rotate around the fixed shaft 7 when driven by the motor 9. It is to be noted that although not shown specifically, the motor 9 is driven in a manner which controls the rotational speed of the rotary cylinder 8 in association with the operating speed at other associated stations, such as filling and labelling stations, which are disposed in the same container handling line as the present capping apparatus.
A turn table 10 is provided as fixedly mounted on the rotary cylinder 8, and the turn table 10 is provided with a plurality of container holders 11 as arranged along the periphery thereof at an equally spaced interval. Also provided immediately above and integral with the rotary cylinder is a capping head assembly which includes a plurality of cap holders 13 corresponding in number to the container holders 11 and arranged above in registry in position with and movable closer to or away from the corresponding container holders 11 and torque motors 12 for driving to rotate the corresponding cap holders 13. The torque motors 12 are fixedly mounted on respective brackets 14, which are, in turn, slidably supported on guide rods 15 fixedly mounted on the rotary cylinder 8 and arranged therearound. And, thus, the brackets 14 are moved up and down as guided by the guide rods 15. A cam rail 16 having a predetermined shape is also provided as extending around the rotary cylinder 8 and fixed in position. The brackets 14 are engaged with the cam rail 16 so that the brackets 14 move up and down as guided not only by the guide rods 15 but also by the cam rail 16.
As shown in FIG. 3, the cap holder 13 is fixedly attached at the bottom end of a driving shaft 20 which is operatively coupled to a rotary shaft 21 of torque motor 12 through a cylindrical connector 22, which is fixedly mounted on the rotary shaft 21 and which is formed with a longitudinal groove in its inner peripheral surface. At the top end of the driving shaft 20 is provided a key 24 which is loosely fitted into the groove 23. Thus, the driving shaft 20 is in sliding contact with the connector 22 and thus may be moved up and down within a predetermined range with respect to the connector 22 while maintaining a power transmitting relation between the torque motor 12 and the cap holder 13. Also provided is a stopper ring 25 fixedly mounted on the driving shaft 20. The stopper ring 25 determines the lowermost position of the cap holder 13 and prevents the driving shaft 20 from slipping away.
The cap holder 13 is provided to temporarily hold a cap 29 to be tightly screwed onto the mouth of the container 3 which stands upright on the turn table 10 and is held in position by the container holder 11. As shown, the cap holder 13 is provided with a pressure chamber 30 a part of which is defined by a disc 31, which is forced to move downward when a pressurized gas is introduced into the pressure chamber 30. A ring-shaped elastic member 32 is also provided partly in contact with and below the disc 31, and the ring-shaped elastic member 32 has an opening whose diameter is slightly larger than the outer diameter of the cap 29 used. Since the disc 31 is provided with a circular ridge extending along the periphery at its bottom, the ridge is normally in contact with the ring-shaped elastic member 32, which is supported on a closure member provided with a center hole large enough for allowing the cap 29 to extend therethrough. Thus, when the disc 31 is pressed downward, the ring-shaped elastic member 32 deforms thereby making its opening smaller in diameter so that the cap 29 becomes temporarily held by the cap holder 13. The pressure chamber 30 is fluid-dynamically connectable to a pressure gas source 38 through passages 33, 34 and 35, conduit 36 and electromagnetic valve 37. It is to be noted that additional passages 39 and 40 are provided in the cap holder 13 from a point where the top surface of the cap 29 comes to be located when held by the ring-shaped elastic member 32 to the atmosphere, whereby the cap 29 is prevented from being stuck to the cap holder 13 due to creation of vacuum at its top.
The torque motor 12 is provided with a r.p.m. detector 45, such as a rotary encoder, and, as shown in FIG. 2, the capping apparatus includes a position detector 46 for detecting the rotary position of the rotary cylinder 8 mounted on its machine housing. Lead lines 47 from the detectors 45 are connected to a control unit 50, such as a microcomputer, through a rotary joint 48, and a lead line 49 from the other detector 46 is directly connected to the control unit 50. The control unit 50 controls an output of each of the torque motors 12 and thus the level of torque for tightening the cap 29 by the cap holder 13 by adjusting the level of electric current supplied to each of the torque motors 12. And, as will be described later in detail, depending on the rotary position of the rotary cylinder 8, during a first stage of the capping operation, a torque applied to the cap 29 by the cap holder 13 is set at a first level which is larger than a predetermined reference level. During the second stage of the capping operation, the torque is set at a second level which is smaller than the predetermined reference level, followed by a third stage of the capping operation in which the torque is set at the predetermined reference level.
With the above-described structure, when the rotary cylinder 8 is driven to rotate by the motor 9, the containers 3 standing on the transporting conveyor 2 still uncapped are lead into the corresponding container holders 11 on the turn table 10 one by one in sequence as regulated by the inlet star wheel 4 and temporarily secured in position on the turn table 10 standing upright. Meanwhile the caps 29 are supplied from a source (not shown) to be individually held by the cap holders 13 as indicated in FIG. 3. When cap 29 is inserted into the opening defined in the ring-shaped elastic member 32, a detection signal is supplied to the control unit 50 by means of a detector (not shown), and, thus, the control unit 50 supplies an activation signal to the electromagnetic valve 37 to have it energized thereby establishing the open condition. Thus, a gas under pressure is supplied into the pressure chamber 30 from the pressurized gas source 38, so that the ring-shaped elastic member 32 deforms thereby temporarily grabbing the cap 29 securely.
FIG. 4 shows, from right to left, a progression of steps which occur during a revolution of turn table 10. First, cam rail 16 moves lower to a starting position S, remains low through steps A, B, and C, and rises again after ending position E. Before reaching the starting position S, with the uncapped container 3 securely held by the container holder 11 in position on the turn table 10 and the cap 29 securely held by the cap holder 13, the torque motor 12 and cap holder 13 gradually descend with the rotation of turn table 10 as guided by the cam rail 16 so that the cap 29 now securely held by the cap holder 13 comes to be fitted onto the mouth of the corresponding container 3. The torque motor 12 is maintained inoperative until it is brought to its lower predetermined position. As indicated in FIG. 4, when the detector 46 detects the condition that the rotary position of the rotary cylinder 8 is at a screwing operation initiation position S, i.e., the condition in which the torque motor 12 is located at its lowered position with the cap 29 becoming fitted onto the mouth of the corresponding container 3, the detector supplies a detection signal to the control unit 50, and, thus, the control unit 50 supplies a first driving signal to the torque motor 12 thereby causing it to be driven at a first torque G which is higher in level than a closure torque F having a predetermined reference level.
The reason why the larger torque G is applied at the first stage of capping operation is to prevent the cap 29 from being improperly oriented, or inclined, with respect to the container 3 to be capped. That is, even if the cap 29 is initially inclined with respect to the mouth of the container 3 when brought into engagement by the downward motion of the cap holder 13, it can be properly oriented with respect to the mouth of the container 3 when driven at the larger torque G. The actual level of this larger driving torque G may be set advantageously in consideration of the material and shape of the cap 29.
Position A on FIG. 4 is that position in the rotation of turn table 10 reached when cap 29 has rotated a single revolution. When the cap 29 has rotated a little more than a single revolution from the initial position S, the cap 29 necessarily becomes engaged with a threaded section of the mouth of the container 3, so that the control unit 50 now supplies a second driving signal to the torque motor 12 whereby the torque motor 12 is driven at a second torque H which is lower in level than the closure torque F. Assuming that the cap 29 has been rotated over a predetermined number of revolutions from the initial position S, the screwing operation for having the cap 29 screwed onto the mouth of the container 3 terminates at least at a position prior to position B indicated in FIG. 4 if the thread engagement between the cap 29 and the mouth of the container 3 is normal. At this time, the rotation of the cap 29 ceases as indicated by a one-dotted line I shown in FIG. 4. At this moment, even if an inertia torque due to rotation, which is higher in level than the torque H, is applied to the cap 29, no problem arises in the present invention as long as the final closure torque F is set larger than such an inertia torque.
When the control unit 50 detects the fact that the cap 29 is not in rotation at position B by the detector 45, it supplies a third driving signal to the torque motor 12 so that the torque motor 12 becomes driven to rotate at the final closure torque F. Thus, the cap 29 can be tightly screwed onto the mouth of the container 3 always at the same torque level. Thereafter, when the control unit 50 detects the fact that the rotary cylinder 8 takes a position C indicated in FIG. 4, it causes the torque motor 12 to stop its rotation and to deenergize the electromagnetic valve 37 thereby releasing the cap 29 from the cap holder 13. Then, through the engagement with the cam rail 16, the cap holder 13 and torque motor 12 are returned to their original upper positions. Meanwhile, the container 3 now properly capped with the cap 29 is transferred from the container holder 11 to the transporting conveyor 6 via the outlet star wheel 5.
If the detector 45 detects at position A the condition that the cap holder 13 is not in rotation, the control unit 50 is preferably so structured to supply an alarm signal for activating an alarm device (not shown). Or, alternatively, it may be so structured that the corresponding container 3 when released from the container holder 11 is transported to a predetermined location through an appropriate mechanism for eliminating the container 3 in question from the normal process line.
On the other hand, if the cap holder 13 is detected to be in rotation at position B and also at position C, since this indicates a faulty condition, it is preferably so structured that the control unit 50 supplies an alarm signal or activates the above-described eliminating mechanism. In FIG. 4, a position E indicates the position which is determined to be prior to the position where the cap holder 13 and torque motor 12 return to their original upper positions through engagement with the cam rail 16 after a time period required for releasing the cap 29 by the cap holder 13. If the control operation by the control unit 50 still continues at position E for some reason, such as malfunctioning, its control operation is forcibly terminated thereby causing the cap 29 to be positively released from the cap holder 13. Instead of using the detector 46, there may be provided another detector for exclusively detecting this position E.
In the above-described embodiment, the level of the torque at the torque motor 12 is directly controlled. However, the present invention is also applicable to the previously described sun gear-pinion combination if a multilevel clutch is provided in the power transmitting system between the sun gear and the pinion, in which the clutch adjusts the level of torque to be transmitted by an appropriate means, such as air pressure. In this case, the clutch transfers torques of different levels depending on the level of air pressure supplied thereto.
While the above provides a full and complete disclosure of the present embodiments of the present invention, various modifications, alternate constructions and equivalents may be employed without departing from the true spirit and scope of the invention. Therefore, the above description and illustration should not be construed as limiting the scope of the invention, which is defined by the appended claims.
|
A capping apparatus includes a turn table which is supported to be rotatable and provided with a plurality of container holders for temporarily holding the containers securely, a plurality of cap holders for releasably holding caps to be screwed onto the mouth portion of the containers, a plurality of torque motors individually provided for rotating the corresponding cap holders and a microcomputer for controlling the level of torque applied to the cap holders by the torque motors. The torque applied to the cap holder during the screwing operation is set to be higher in level during the first revolution of the cap and lower in level during the remaining rotation of the cap than the torque applied upon completion of the screwing operation so that the caps can be screwed onto the threaded mouth portions of the containers all at the same tightening level.
| 1
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 14/382,192, which is the United States national phase under 35 U.S.C. §371 of PCT international application no. PCT/EP2012/000956, filed on Mar. 2, 2012.
BACKGROUND OF THE INVENTION
Field of the Invention
Embodiments relate to methods for automatically licensing features during the upgrade of a first communication system to a second communication system, a computer program and a licensing system to perform such method.
Background of the Related Art
Modern communication systems such as telephone systems for small, medium and large enterprises are configurable and scalable in many ways, for example using CTI (Computer Telephony Integration) and CSTA (Computer Supported Telecommunications Applications). Mostly, the determined features are activated by means of a file containing licensing data.
A change in the scope of features to be licensed is often associated to the upgrade of such a system. The reasons for this can be legal reasons (for example, required royalty payments to licensors), economic reasons (for example, if customers are to pay for a feature in a new version) or technical reasons (for example in old versions, as many TDM as available ports could connected while for a new system, a license is required for each TDM device). TDM stands for Time Domain Multiplex and refers to a telecommunication device which uses a time multiplex procedure as for example in “conventional” devices such as wireless phones, but not as in IP phones.
According to internal company procedures, the upgrade of telecommunication systems may typically be carried out manually according to the following procedure:
1. A special user (who in many cases is a product manager or PM) acquires a quantity of licenses also known as PM-licenses for new systems using standard procurement procedures. Different scenarios for “New Systems” are possible: It can be the hardware of a legacy system on which new software or new software features are updated or upgraded. It can be as well the use of new hardware which can operate new software with newly licensed features.
2. As a further step of the ordering procedure the license fees are paid.
3. After the ordering process is completed, the licenses become available on the PM's account.
4. Whenever a customer wants to upgrade an old system, he sends to the PM a proof of the presence of the features on the old system. This proof can be provided in the form of screenshots, a delivery slip for the TDM devices or the like.
5. The PM sends the new licenses manually to the customer's account.
6. This customer will then activate the new licenses.
The procedure described above has a number of disadvantages:
1. The PM must in each case estimate in advance how many are needed.
2. The royalty payment is made before the actual use or activation of the licenses, which is sooner than required.
3. Generally, the licenses are not immediately available, since the ordering process takes some time.
4. The required evidence is not safe and there is room for abuse.
5. It can be impossible or very difficult to ensure that new licenses are not enabled on systems that have not been upgraded. In other words, it is difficult to prevent that such licenses are used to upgrade an existing communication system on which no “old” license or software was installed and to configure and activate it as functional system.
Another fundamental problem is that the upgrade is a manual process requiring a significant effort and thus generating significant training and implementation costs as well as costs to correct errors and avoid errors.
BRIEF SUMMARY OF THE INVENTION
We provide a method for automatically licensing features during the upgrade of a first communication system to a second communication, a corresponding computer program, and a corresponding licensing system.
According to an embodiment of the invention a computer aided and computer-based method for automatically licensing features during the upgrade of a first communication system to a second communication system (where the first communication system does not necessarily have to be different from the second one in terms of hardware or software) includes the following steps: first, the features that need to be licensed are extracted from a database. This database can be built, for example, from existing features in the first communication system. Then, the features which have to be licensed are transmitted to a license server and a license file is created, which is then transmitted to the second communication system and is installed there also.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows schematically the components of a license system according to man exemplary embodiment of the invention and
FIG. 2 illustrates a flow chart of an exemplary embodiment of a method for automatically licensing service features during the upgrade of a first communication system to a second communication system.
DETAILED DESCRIPTION OF THE INVENTION
The method according to the invention replaces the usual manual workflow with an automated procedure. The method can be executed in a simple and cost-effective manner, and it eliminates the need for licenses that are used later to be purchased and paid for in advance. By extracting the features to be upgraded from existing databases and by transferring them to the license server, a simple and automated procedure is ensured.
According to an advantageous embodiment of the method, the step of extracting the features to be licensed from the database comprises a step of reading the features of the first communication system and depositing the data in a customer data memory. Thus, these data and features can be transferred as a compact unit, which can for example be done in binary format by means of an appropriate software tool.
It is advantageous to convert the content of the customer's data memory and to expand it with further information, such as, for example, as given by means of the MAC address. Furthermore, it is advantageous if the step of transmitting the features that need to be licensed to the license serve comprises a step of transmitting the converted content of the customer data memory to the second communication system, and in addition a step of generating and transmitting an inventory file to the license server. All the customer data (at least the essential customer data) are included as an “Inventory” for example in this inventory file. The security of the transmission and the protection against fraud can be substantially increased if the inventory file is cryptographically signed.
A particularly simple and safe process implementation is possible because a License Authorization Code is entered on the license server. This license authorization code specifies and determines the licensed features, and also which features need to be upgraded. The License Authorization Code can be used for an order to upgrade a version or to acquire additional licenses.
It may be advantageous if the license server could check first whether or not the first communication system is upgraded. So it can be prevented that an old system without any license would be upgraded through an upgrade license.
Furthermore, it may be advantageous that the license server runs a verification step to prevent another upgrade of a second communication system. This means that for example, when replacing old hardware with new hardware, systems cannot be upgraded via the license server. To this end, a lock table is created, and by doing so, the MAC address of the old hardware, that has to be retired and replaced with new hardware, is captured which prevents the upgrade of the old hardware with an upgrade license. This greatly reduces possible fraud.
Embodiments may also provide a computer program or computer program product according to claim 9 for carrying out any of the methods described above. The advantages and characteristics associated to the methods previously described are similarly applicable to the computer program, an therefore no separate description is provided.
Embodiments may also provide a licensing system. Such a licensing system includes a first communication system, a second communication system (which must not necessarily be different from the first communication system in terms of hardware and/or software), as well as a license server. The advantages and characteristics of the licensing system according to the invention are similar to those previously described with regard to the methods and are therefore not described again.
As already mentioned, no upfront licenses a required by the method and the computer program and licensing system according to the invention, which is why the royalty payment to the licensor does not take place until the date on which the licenses are needed. It is also possible that an upgrade may optionally be carried out without ordering licenses, provided this is allowed by the system. This would be the case, for example, that when switching to new hardware, the new or additional licenses will be provided free of charge.
It should also be noted that all transactions are documented and can be easily understood. The inventory file includes all previous features (excluding the upgrade newly added features.)
According to the invention it is thus possible to prevent in a simple way that new licenses are activated on systems that were not upgraded since proof of the presence on the old systems must first be provided.
Further advantages, features and characteristics of this invention will become apparent from the following description of an advantageous embodiment of both the method and the licensing system that can be appreciated from FIGS. 1 and 2 .
The license system 10 comprises a first communication system 11 and a second communication system 12 that are shown. The first communication system 11 is an old system and the second communication system 12 is a new one which includes hardware changes. As already stated, the two communication systems 11 , 12 can be the same and only differ in software and/or licenses.
A telecommunication system called OSO MX V3 by Siemens Enterprise Communications is used as an example for the first communication system 11 , while the next generation communication system called Next-GenSME is used as an example for the second communication system 12 . An application 14 for the administration of customer data (“ManagerE”), reads the customer data on the first communication system 11 and stores it in so-called customer data memory KDS. This KDS customer data memory is then transferred as a binary file to the ManagerE. Here a stored the number of the features that have not been licensed on the first communication system 11 , but that are defined by means of other features (e.g. a proper hardware system). In this example it is the number of physically installed TDM devices or TDM users. This feature previously available for free should be considered as part of the version upgrade since it needs to be licensed on the new version of the product (NextGenSME, for example).
The number of features that must be upgraded (e.g. TDM users) is determined from the customer data memory by using a KDS-conversion. Here, the customer data include additional information (in particular the MAC address of the system they belong to.)
The converted content KDS' of the customer data memory KDS is transferred to the second communication device 12 . A so-called inventory INV file is generated in the second communication system 12 and cryptographically signed.
The Inventory file INV is transferred to the license server (also called Central License Server) CLS using the WBM/CSCM interface for online licensing via the Internet. WBM stands for Web-Based Management, which is used for the administration of a communication system 11 or 12 on a web server with an interface to a browser. CSCm stands for Customer Site Components modular, which is an interface between the WBM and the license server and is used to establish a connection to the license server for the online licensing procedure. A license file LF is downloaded from the license server CLS and the content of the loaded license is displayed in the WBM. In addition, a license authorization code LAC is entered via the WBM. A license order for a version upgrade and optionally for additional licenses is issued. To ensure that the inventory file was not tampered with, the license server CLS can verify the signature and also ensure by means of the MAC address in the transferred Inventory File and of a revocation list created in a database DB that the original system has not been upgraded yet. The presence (payment) of the available licenses required for the planned upgrade can be checked by means of the transmitted License Authorization Codes LAC. The license server CLS generates the license file LF for the second communication system 12 taking into account the data in the inventory file, as well as the purchased licenses that are referenced via the License Authorization Code LAC. To avoid a further activation of the Inventory INV files on another system or in another communication system, the license server CLS records the MAC address from the inventory file in the revocation list. In case of an attempt to upgrade a communication system whose corresponding MAC address is listed in the revocation list, an error message appears, and the licensing process is canceled. This greatly enhances the security and protects against fraudulent licensing.
The generated license file LF (also called license data) will be sent via the Internet interface to the second communication system 12 where it is installed. Subsequently, the second communication system 12 can be used with all the upgraded features.
It should be noted that the described features of the invention with reference to the illustrated embodiment of the invention, such as sequence and exact execution of the individual method steps and the software and hardware components used, may be present in other embodiments and, except when otherwise indicated or prohibited for technical reasons.
|
The invention relates to a method for automatically licensing service features during the upgrade of a first communication system ( 11 ) into a second communication system ( 12 ), said method having the following steps: (a) extracting the service features to be licensed from a database, (b) transmitting the service features to be licensed to a License Server (CLS), (c) generating a license file (LF) in the License server (CLS), (d) transmitting the license file (LF) to the second communication system ( 12 ), and (e) installing the license file (LF) in the second communication system ( 12 ). This invention also relates to a corresponding computer program and corresponding licensing system.
| 7
|
CONTINUATION APPLICATION
This application is a continuation-in-part of application No. 07/402,628, Filed Sep. 9, 1989, which was a continuation-in-part of application No. 07/181,054, Filed Apr. 13, 1988, both now abandoned.
This invention relates generally to compositions and methods for cleaning, and more particularly, relates to a composition and method for cleaning and lubricating hair shears and the like.
BACKGROUND OF THE INVENTION
Shears that are used for grooming hair have blades that are used to clip or cut the hair. Cutting is effected by movement or oscillation of the blades relative to one another. Through use, the blades of the shears become fouled by hair particles, dirt, body oils, hair grooming preparations and other miscellaneous, undesirable particles that may become lodged in the hair.
Fouling of the blades hinders the efficient operation and use of the shears. Material which fouls blades can be abrasive enough to dull the blades as they move or oscillate. Dull blades do not cut hair efficiently. They tend to pull hair rather than cut, causing pain and discomfort to the person whose hair is being cut. The pulling action can then cause the shears' blades to pinch or abrade the scalp. This causes additional pain and discomfort and also creates the possibility for germs to infect the scalp through the pinched or abraded area. As can be seen, fouling requires that blades be sharpened more frequently.
The operation of shears is further hindered by fouling in that there is greater friction between fouled blades than clean blades. There is a certain amount of friction and temperature increase which is caused by general movement of the blades relative to one another; however, the greater friction causes the temperature of blades to increase even more, possibly beyond design parameters. The hotter blades are more easily dulled by abrasive foreign particles. In addition, if there is sufficient friction caused, the blades can become so warm as to create discomfort for the person whose hair is being cut.
When there is an increase in the amount of friction that takes place between blades of electric shears, the amount of work which must be done by the motor which drives the shears also increases. The increased load places an extra burden upon the motor that reduces its efficiency and decreases its life.
Fouling of blades of hair shears causes another problem in that the fouling material, namely, oils, dirt, hair particles and the like, inhibit the free flow or air through the blades. The free flow of air is important because that is the primary manner in which heat is dissipated from moving blades. Thus, inhibited air flow increases the problems arising from an excessive increase in operating temperature.
It can be seen that it is important to keep the blades of shears clean. It can also be seen that it would be advantageous to lubricate the blades to decrease friction. Accordingly, it would be highly desirable to have a cleaning composition and method for cleaning and lubricating the blades of shears.
There are problems involved in cleaning shears. One problem is that body oils and oils from hair grooming aids are difficult to remove from the blades. In addition, these oils mix with dirt and other undesirable particles and make the mixture extremely difficult to remove from the blades. In general, oily substances cling to the blades and are not easily removed by wiping or agitation.
Another problem in cleaning shears is that the cutting blades are very closely positioned with respect to one another. The close alignment of blades is essential for optimal cutting but hinders effective wiping or brushing of the spaces between the blades.
The two problems discussed immediately above may be solved by using a liquid to penetrate the hard-to-reach areas between the blades and dissolve and remove the oily fouling material. Accordingly, it would be highly desirable to have a cleaning composition and method that effectively removes oily substances from hard-to-reach areas of shears.
Water and aqueous solutions unsuitable for cleaning the blades of shears for several reasons. Water alone will have virtually no effect on oils or oily substances. The water in aqueous solutions causes oxidation or corrosion of metal blades. Oxidized or corroded blades will not perform desirably. Water or water-based solutions are particularly unsuitable for cleaning electric shears because the electricity-conductive properties of water may cause electrical shock or short circuiting of clipper components.
A solvent which is capable of dissolving oily substances and dirt which does not exhibit the harmful characteristics or water described above would be most appropriate for a cleaning solution. A petroleum based solvent would meet these requirements. Kerosene, in particular, has been used to clean shears. However, kerosene has a strong, unpleasant odor which makes it an undesirable cleaning product. Also, kerosene alone is ineffective as a lubricant. Accordingly, it would be highly desirable to have a cleaning composition that both cleans and lubricates and also has a pleasing aroma.
Human hair normally contains germs. It is undesirable to transmit these germs from one person to another. Thus, it is prudent to both clean hair shears and apply an antiseptic to the shears after each use to prevent the spread of germs. The use of an antiseptic also helps prevent the infection of any cut or abrasion that comes about when a person is having his or her hair groomed. Accordingly, it would be highly desirable to have an antiseptic cleaning composition that not only cleans and lubricates but also inhibits the spread of germs and infections caused by germs.
U.S. Pat. Nos. 4,759,867; 4,654,374; 4,632,72 and 3,882,038; and U.K. Patent Application GB 2 173 508A, disclose hard surface cleaners. While the metal surfaces of the blades of hair shears are hard surfaces, these hard surface cleaners are unsuitable for cleaning hair shears because these cleaners contain acid or water. The reasons why an aqueous solution is unsuitable as a cleaner have been enumerated above. An acid cleaner is unsuitable in and of itself because it would corrode the metal blades. Acid may also be harmful to the plastic casing which houses most shears' motors and mechanisms.
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, a cleaning solution contains an aliphatic hydrocarbon with a small amount of fragrance, and an antimicrobial agent. Shears are cleaned, in general, by immersing the blades of the shears in the cleaning compound, placing the blades in motion for five or six seconds while they are immersed in the compound and, finally, removing the shears and wiping off excess cleaner from the shear.
It is an object of the present invention to provide a cleaning composition that cleans and lubricates the blades of shears. This object is achieved by adding a silicone lubricant to a nonchlorinated aliphatic solvent.
It is also an object of the present invention to provide a cleaning composition that cleans blades and is a good lubricant at low and high temperatures. This object is achieved by adding a silicone lubricant and mineral oil to a nonchlorinated aliphatic solvent.
Another object of the present invention is to provide a cleaning composition that cleans and lubricates and has a pleasing aroma. A pleasant aroma is given to the compound by the addition of a small amount of fragrance to the nonchlorinated aliphatic solvent.
Still another object of the present invention is to provide a cleaning composition with antiseptic properties that inhibits the spread of germs. This object is achieved by the addition of a small amount of an antimicrobial agent.
A further object of the present invention is to provide a cleaning composition that does not rust or corrode the blades of shears which are cleaned. The solution of the present invention does not contain water and is non-acidic. The solution does not promote rust or corrosion on the metal blades of shears.
A still further object of the present invention is to provide a method for cleaning and lubricating hair shears. An additional object of the present invention is to provide a simple, easy method for cleaning and lubricating hair shears. The present invention provides a method of immersing shears in a cleaning, lubricating antimicrobial compound.
BRIEF DESCRIPTION OF THE DRAWING
The drawing illustrates a pair of electric clippers being immersed into a container filled with a cleaning solution in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing, the cleaning solution 10 of the present invention is a highly refined petroleum-based cleaner developed for everyday maintenance of hair shears, especially electric hair clippers 12. The cleaner 10 helps electric clippers 12 run cooler and more efficiently. The cleaning solution 10 will also prolong the life of electric shears and help keep the blades 14 sharp by removing dirt from the teeth of the blades 14. The cleaner 10 contains a petroleum-based solvent which easily dissolves the oil that causes hair and dirt to adhere to the teeth of the blades 14 of the clippers 12. The cleaner 10 is also suitable for manually-operated hair shears which are susceptible to the same dirt and debris as electric hair shears 12.
The cleaning solution 10 contains an aliphatic hydrocarbon as its base solvent. An aliphatic hydrocarbon is preferred over an aromatic, or cyclic, hydrocarbon as a base solvent for the cleaning solution because the latter type of hydrocarbon is likely to dissolve or distort the plastic casings of electric shears. A non-chlorinated solvent is used in the solution because chlorine is also likely to dissolve or distort the plastic casings of electric shears. The hydrocarbon can be further described as a petroleum distillate having a boiling range of from about 350 degrees to about 555 degrees F., a natural flash point greater than or equal to 140 degrees F., and a kauri butanol value of less than or equal to 30. An example of a suitable solvent is Low Odor Base Solvent manufactured by Ashland Chemical, Inc. By volume, the cleaning solution 10 contains about 85 to 95 percent aliphatic hydrocarbon. Using less than about 85 percent aliphatic hydrocarbon increases the cost of the solution because the costs of the other additives necessary to comprise the solution in sufficient total volume to be effective is comparatively greater.
The cleaning solution 10 also contains about 4 to 12 percent silicone. The silicone should have a viscosity in the range of 100-1,000 cs. measured at 77 degrees F. Preferably, the silicone is a 350 cs. viscosity dimethylpolysiloxane, such as DOW CORNING 200 fluid. When more than about 12 percent silicone is used the cost of the cleaning solution increases with no great increase in lubricity. When less than about 4 percent silicone is used a loss of lubricity is possible. The silicone is a good metal to nonmetal lubricant.
The cleaning solution also contains about 1 to 20 percent mineral oil. Mineral oil mixes well with the other ingredients in the compound and is a good metal to metal lubricant. When more than about 20 percent mineral oil is used, the solution becomes too oily. When less than about 1 percent is used, the mineral oil becomes ineffective. Preferably, the mineral oil is pharmaceutical grade. The combination of both lubricants provide lubrication over a wide range of temperatures.
A fragrance can be added to the cleaning solution to impart a very pleasing aroma. Suitable fragrances are H-8607 Unisex and H-8593 Baby Powder. These are common denotations in the chemical industry for artificial fragrances. Preferably, the fragrance comprises from about 0.05 to about 0.8 percent by volume of the cleaning solution. At volumes below about 0.05 percent, the fragrance is not very noticeable, and at volumes about 0.8 percent, the fragrance is very strong and unnecessarily increases the cost of the solution.
An antimicrobial agent can also be added to the cleaning solution to kill and inhibit the growth of microbes. Preferably, the antimicrobial agent comprises from about 0.1 about to 5.0 percent by volume of the cleaning solution. At volumes below about 0.1 percent, the antimicrobial agent is ineffective, and at volumes above about 5.0 percent no additional benefits are gained.
The cleaning solution cleans, conditions and lubricates shears. The cleaning solution does not contain hazardous chlorinated solvents and has a flash point greater than or equal to 140 degrees F., making it a safer cleaner that leaves the shears thoroughly cleansed and lubricated. A fragrance added to the cleaning solution give the cleaning solution a very pleasant aroma.
The cleaning solution also contains a very proficient antimicrobial agent. The cleaner is designed for cleaning at ambient temperatures for dip, brush, wipe or spray methods of cleaning. The solution of the invention is a cleaner with a very mild fragrance that helps the shears run cooler longer and cut better, and helps the blades stay sharp by removing hair, grease, oil and dirt from the teeth of the blades. The solution is substantially free of water because non of the ingredients contain more than about 500 parts per million of water. The solution has a non-acidic, neutral pH because of the ingredients used. Thus, the solution does not promote rusting or corrosion or short circuiting of electrical components when electric shears are cleaned.
The clipper cleaning solution can be made by mixing 55 gallons of aliphatic hydrocarbon (deodorized) with 1 gallon, 350 cs. viscosity dimethylpolysiloxane such as DOW CORNING 200 fluid and 5 gallons of NF grade light mineral oil.
The aroma can be improved by adding 0.25 gallons (or 32 ounces) of a fragrance such as H-8607 Unisex or H-8593 Baby Powder. The microbe-inhibiting properties of the cleaning solution may be improved by adding about 2 to 10 pounds of an antimicrobial agent, for example an O-phenylphenol, such as DOWICIDE 1.
The cleaning solution is used to clean electric shears 12 by submerging cool electric hair clipper blades 14 in the cleaner 10, turning the clippers 12 on and letting the clipper blades 14 stand in the cleaner 10 for five to six seconds. The clippers are then turned off, excess cleaning solution 10 is wiped, shaken or similarly removed from the blades, and the clippers are ready for use.
While the invention has been described with particular reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements of the preferred embodiment without departing from the letter and spirit of the invention. For example, while the invention has been described with particular emphasis on electric hair shears, the cleaning solution is equally effective for other tools, electrical motors, implements and devices. In addition, many modifications may be made to adapt a particular situation and material to a teaching of the invention without departing from the essential teachings of the present invention.
As is evident from the foregoing description, certain aspects of the invention are not limited to the particular details of the examples illustrated, and it is therefore contemplated that other modifications and applications will occur to those skilled in the art. It is accordingly intended that the claims shall cover all such modifications and applications as do not depart from the true spirit and scope of the invention.
|
A solution for cleaning and lubricating hair shears and the like contains a nonchlorinated aliphatic hydrocarbon, dimethylpolysiloxane, mineral oil, a small amount of fragrance and a small amount of an antimicrobial agent. The blades (14) of hair shears (12) are immersed in the solution (10) and oscillated to loosen and remove fouling particles. The shears are then withdrawn from the solution and excess solution is removed to ready the clippers for use.
| 0
|
TECHNICAL FIELD
[0001] The present invention relates generally to stimulating subterranean hydrocarbon reservoirs and injector wells in the oilfield services industry. More specifically, this invention relates to proppant pack cleaning.
BACKGROUND OF THE INVENTION
[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0003] Stimulation of subterranean hydrocarbon reservoirs and injector wells are widely carried out in the oilfield services industry. The most common techniques, including matrix acidizing, hydraulic fracturing, acid-fracturing, sand control, enhanced oil-recovery, etc. use aqueous fluids to impact hydrocarbon productivity. However, the majority of the aqueous fluids are executed with little knowledge of or consideration for the wettability (water-wet or oil-wet) or the partial water/oil saturation of the rock being treated. In fact, a large number of impediments to production can be attributed to improper formation-wettability.
[0004] Water-blocks often result from increased water-production occurring through any of the well-known water-problem types. Water-blocks in the formation are one of the most well-known formation damage mechanisms that diminish hydrocarbon productivity. However, many water-control and water-block remediation treatments are not designed for long-term formation wettability. Issues of wettability are particularly critical in the porous matrix of sandstone reservoirs, where the pore throat diameters are often very small (<10 μm) and thin water-wet/oil-wet coatings of the formation can constrain those pore throat diameters even further. In matrix acidizing, reactive acid fluids are intended to dissolve damaging mineral deposits or other induced particulate damage that may be, at the time of treatment, oil-wet, leaving the immiscible aqueous acid incapable of contacting a large portion of the damaging minerals. In acidizing fluids, “mutual solvents” are often added to temporarily reduce the interfacial tension between the acid and hydrocarbon; amphiphilic surfactants are often added to the acid to leave the formation water-wet enabling more efficient acid/mineral contact. In hydraulic fracturing, formation-wettability is generally considered less important because a) the exposed formation surface area is greatly increased due to the formation of a large fracture and 2) because the hydraulic fracturing fluid is not needed to dissolve mineral damage, consideration of the wettability of the formation adjacent to the fracture is generally not taken into consideration.
[0005] However, a large volume of aqueous fracturing fluid leaks off into the formation through the fracture-faces and as a result of its immiscibility with hydrocarbon can be very slow to return to the surface due to the sandstone being preferentially water-wet. A major failure to achieve expected stimulation from a fracturing treatment is through imbibement of water in the formation and proppant pack that is detrimental to hydrocarbon production. The same types of amphiphilic surfactants that are used in acidizing fluids are often added to fracturing fluids for reduced interfacial tension and wettability modification. However, these same surfactants have been used for many decades in stimulation fluids and their mechanism of action is ill-understood and is rarely tailored to formation or fluid properties. These surfactants have been widely proposed as additives for fracturing fluids that will absorb to solid substrates (such as formation or proppant) rendering those surfaces hydrophobic. Capillary pressure in the matrix or pack treated by these surfactants is impacted by both altered wettability and reduced surface tension after their absorption. However, surfactants do not form a persistent or covalent coating on the surface of the formation or proppant and offer only a temporary modification to the formation wettability. They are often swept from the formation surface with aqueous treatment fluid flowback or with the onset of hydrocarbon production.
[0006] Improved methods to resolve wettability issues inside the proppant pack of a fracture generated during a hydraulic fracturing treatment are needed. Though the porosities of propped-fractures are much higher than a sandstone matrix/formation, and issues of wettability are less critical in affecting production through the proppant pack. However, certain properties of the proppant pack and fluid filter-cakes could impact the wettability of the proppant pack. For example, resin-coated proppants are used frequently for proppant-flowback control and are generally oil-wet. However, resin-coated proppants have a number of incompatibilities with a number of carrier fluids due to the polymer coating-chemistry and certain fines that are formed in the manufacturing of the resin-coated proppant.
[0007] In general, the understanding of sandstone and other formation wettability has greatly advanced in recent years. However, the identity and chemical properties of additives to affect and control wettability (including the chemistry of surfactant additives to stimulation fluids) has not changed. Methods and compositions to tailor wettability properties are desirable.
SUMMARY OF INVENTION
[0008] Some embodiments provide a method and composition for treating a subterranean formation with a fluid, including forming a fluid including a particulate and an organosilane with the chemical formula R n SiX 4-n, wherein n is equal to 1, 2, or 3, R is an organic functional group, and X is a halogen, alkoxy, or acetoxy group, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of a surface of the particulate or subterranean formation or both. Some embodiments provide a method and composition for treating a subterranean formation with a fluid including forming a fluid comprising a particulate and an organosilane, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of the proppant or surfaces or both, wherein the wettability modification degrades. Some embodiments provide a method and composition for producing hydrocarbon from a subterranean formation, including providing a wellbore in a subterranean formation, forming a fluid including a particulate and an organosilane with the chemical formula R n SiX 4-n, wherein n is equal to 1, 2, or 3, R is an organic functional group, and X is a halogen, alkoxy, or acetoxy group, introducing the fluid into the subterranean formation with exposed surfaces, modifying the wettability of a surface of the particulate or the subterranean formation or both, and producing hydrocarbon from the wellbore in the subterranean formation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a chemical formula of an embodiment.
[0010] FIG. 2 is a summary chart of example 1.
[0011] FIG. 3 is a summary chart of example 2.
[0012] FIG. 4 is a schematic illustration of equipment used to test an sample of an additional embodiment.
[0013] FIG. 5 is a plot of peak area as a function of days of an additional embodiment.
[0014] FIG. 6 is a plot of peak area as a function of days of an additional embodiment.
[0015] FIG. 7 is a plot of absorbance as a function of a wavenumber of an additional embodiment.
[0016] FIG. 8 is a plot of peak area as a function of days of an additional embodiment.
[0017] FIG. 9 is a plot of peak area as a function of days of an additional embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Methods of forming and applying fluids, slurries, or coatings that include compositions of specific classes of organosilanes may be used to control and tailor the wettability properties of a proppant pack and surrounding surfaces. These classes of organosilanes include a hydrophobic moiety, a hydrophilic moiety, an amphiphilic moiety, or a hydrophobic or hydrophilic group with a terminal reactive functionality or other tailored chemical property or a combination thereof. The length of the alkyl (organic) portion of an organosilane, the concentration of silicon within the organosilane, the presence of a spacer within the organosilane and other factors may influence how the organosilane tailors the hydrophobic or hydrophilic nature of the proppant pack and surfaces and influence the wettability of the system.
[0019] In the following detailed description, reference is made to the accompanying drawings that show, by way of illustration, specific 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. It is to be understood that the various embodiments of the invention, although different, are not necessarily mutually exclusive. For example, a particular feature, structure, or characteristic described herein in connection with one embodiment may be implemented within other embodiments without departing from the spirit and scope of the invention. In addition, it is to be understood that the location or arrangement of individual elements within each disclosed embodiment may be modified without departing from the spirit and scope of the 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, appropriately interpreted, along with the full range of equivalents to which the claims are entitled. In the drawings, like numerals refer to the same or similar functionality throughout the several views.
[0020] It should also be noted that in the development of any such actual embodiment, numerous decisions specific to circumstance must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
[0021] Four families of organosilanes may be used in subterranean applications to provide tailored fluids or coatings for controlling wettability. These silanes are based on the general chemical formula: R n SiX 4-n, where “R” is the organic functionality that will be exposed terminally from the solid (quartz or sand) substrate after reaction, and X may include halogens (X═Cl − , F − , Br − , or I − ) or alkoxy groups (a nonexclusive list of examples includes methoxy, ethoxy, or oligo(ethyleneglycol)oxy groups). Alkoxy groups may be slower acting than the halogens. Most often, n is 1 and the resulting additives are trihalo or trialkoxysilanes. N may also be 2 or 3. However, other organosilanes have multiple organic functionalities.
[0022] The first group of organosilanes occur when R is a hydrophobic moiety, such as a linear, branched, or polymeric alkane. Hydrophobically modified silanes are well known for imparting a hydrophobic character to SiO 2 surfaces. In subterranean applications, this would be considered an “oil-wetting” modification to the surface. Examples of hydrophobic R groups include linear (such as methyl, octyl, octadecyl, etc.), branched (t-butyl, 2-ethylhexyl, etc), or polymeric alkanes. Other hydrophobic alkyl modifications include phenyl, benzyl, tolyl, or other partially-unsaturated alkyl groups. A desirable group of hydrophobic R groups includes partially or fully fluorinated alkyl derivatives. Suitable silanes may include linear alkyl silanes (such as methyltrimethoxysilane, hexyltrimethoxysilane, heptyltrimethoxysilane, and octadecyltrimethoxysilane), alkyl silanes with 2 or less hydrolysable groups (such as propylmethyldimethoxysilane, propyldimethylmethoxysilane, and trimethylmethoxysilane), branched alkyl organosilanes (such as isooctyltrimethoxysilane and cyclohexyltrimethoxysilane), partially unsaturated organosilanes (such as phenylethtrimethoxysilane, benzyltriethoxysilane, and p-tolyltrimethoxysilane), and partially fluorinated organosilanes (such as 1H,1H,2H,2H-perfluorodecyltrimethoxysilane, nonafluorohexyltrimethoxysilane, and 3,3,3-trifluoropropyltrimethoxysilane).
[0023] The second group of organosilanes occur when R is a hydrophilically functionality that is generally polar (non-hydrogen-bonding), polar (hydrogen-bonding), hydroxylic, or ionic charged; these groups may include oligo(ethylene glycol) groups, oligo(propylene glycol) groups, polar groups (substitution), or polymers, or polyamide groups. These organosilanes may also include dipodal or polypodal organosilanes (with multiple silane attachments to the surface for each organic group. Examples of polar, non hydrogen-bonding organosilanes may include 2-cyanoethyltrimethoxysilane or Bis[(3-methyldimethoxysilyl)propyl]-polypropylene oxide. Examples of polar hydrogen-bonding organosilanes may include 2-[methoxy(polyethyleneoxy)propyl[-trimethoxysilane and Bis[N,N′-(triethoxysilylpropyl)aminocarbonyl]polyethylene oxide. Examples of hydroxylic organosilanes may include Bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, N-(3-triethoxysilylpropyl)gluconamide, and N-(triethoxysilylpropyl)-O-polyethylene oxide urethane. Examples of charged hydrophilic organosilanes may include carboxyethylsilanetriol, octadecyldimethyl(3-trimethoxysilylpropyl)ammonium chloride, and 3-trihydroxysilylpropylmethylphosphonate. The action of these hydrophilically-modified silanes would be to impart a preferential “water-wet” character to the surface.
[0024] The third group of silanes includes amphiphilically-modified organosilanes, occurring when R is a diblock modification where a hydrophobic (linear or branched) alkane is attached to a hydrophilic group (including the polar, hydrogen-bonding, hydroxylic, or charged groups as described above, such as oligo(ethylene glycol) and oligo(propylene glycol) groups) through a linkage that breaks or degrades with time at conditions (including temperature) that are experienced downhole (such as through ester, amide, persulfate, or peroxide groups). With a terminal hydrophobe and internal hydrophilic group, a surface treated with this family of additives would be initially oil-wet and would switch to water-wet through degradation of the diblock linkage. The initial oil-wet character of the placed proppant pack is useful for both simplified proppant suspension and for rapid unloading of the aqueous carrier fluid after fracturing (once production from the fracture has begun). The hydrophilic surface character after the degradation reaction should be nearly as hydrophilic or more hydrophilic compared to unmodified proppant surface (which is generally understood as hydrophilic). One proposed degradation of a model degradable-diblock organosilanes is shown below in FIG. 1 , though other degradation reactions (such as amide hydrolysis) exist.
[0025] In FIG. 1 , the terminal moiety is the hydrophobic group and the oligo(ethylene glycol) group represents the hydrophilic group. In this example, hydrolysis of the ester linkage between the two blocks will turn the initially hydrophobically-coated substrate into a hydrophilically-modified coating. Examples of suitable diblock degradable coatings may include 2-[acetoxy(polyethyleneoxy)-propyl]triethoxysilane, acetamidopropyltrimethoxysilane, N,N-dioctyl-N′-triethoxysilylpropyl urea, (3-triethyxysilylpropyl)-t-Butylcarbamate, and S-(octanoyl)mercaptopropyltriethoxysilane.,
[0026] A second means to achieve degradation of the initial hydrophobic surface character is through degradation of the organosilane coating at the silane surface. That is, slow removal of the organosilane molecule could occur in such a way to remove the organosilane/organosilanol rendering a surface that behaves chemically comparable to its original uncoated character and wettability.
[0027] The fourth family of organosilanes includes silanes, occurring when R is a hydrophobic or hydrophilic group with a terminal reactive functionality, including a vinyl, sulfate, sulfonate, phosphonate, carboxylate, tertiary ammonium, or similar reactive or charged moieties.
[0028] The X-functionality in organosilanes depends on the moisture-sensitivity of the silane as imparted by the X group. Trihalosilanes are notoriously water-sensitive and when exposed to water will self-condense through equation (1), to form a polysiloxane:
[0000] RSiX 3 +RSiX 3 +H 2 O→2HX+RX 2 SiOSiX 2 R (1)
[0029] However, equation (1) only depicts a condensation of 2 organosilanes and the removal of only 1 X group from each; this reaction is very favorable when X is a halogen such as chloride. Most often, all “X” leaving groups would hydrolyze similarly, possibly leading to a final R—SiO 3 Si—R species (or larger polysiloxane oligomer). Further polycondensation will react all of the X groups of a large number of organosilanes at the same time leading to such larger polysiloxane oligomers. Because the subterranean environment is so rich in water, it is likely that this polycondensation would be too rapid and may occur prior to the organosilane reaction with the quartz or proppant substrate. However, organosilanes when X is an alkoxy or acetoxy group are much slower-reacting in self-condensation and are therefore less moisture-sensitive and are often desirable for subterranean applications. Moreover, some alkylalkoxysilanes are so moisture-insensitive that they are water-soluble and are deployed in aqueous media. The principal advantage of organosilanes for wettability-modification compared to surfactant additives is that their reaction with the SiO 2 substrate forms a permanent covalent bond, leading to a long-term modification of the wettability.
[0030] Methods of using coated proppants may be formed with a coating to promote faster cleanup of aqueous fracturing fluid. SiO 2 -based sand used as a proppant in hydraulic fracturing could be coated either in commercial facilities or on the surface at the wellsite with hydrophobically modified organosilanes (including alkyltrihalosilanes (such as octadecyltrichlorosilane, OTS) or alkyltrimethoxysilane derivatives). Conversely, stable organosilanes could be injected in the carrier fluid along with the proppant and could simultaneously coat the proppant pack and the formation (through fluid leakoff). The hydrophobically-modified surface is oil-wet and as such, repels the aqueous carrier fluid. This both minimizes the ability of the (often polymeric) fracturing fluid to condense to form a filtercake directly on the proppant and encourages the aqueous fracturing fluid to efficiently flowback to the surface after the treatment.
[0031] Also, a water-wet coating on proppant particles promotes more efficient hydrocarbon production through the proppant pack. Again, hydrocarbon production through the proppant pack is more efficient when controlled wettability and repulsive forces between a preferentially water-wet proppant and the immiscible hydrocarbon phase (during production) is controlled. Siliceous surfaces such as sand, quartz, glass, and many clays are already water-wet and it would be desired to return that water-wet character after the aqueous fluid is returned to recover efficient hydrocarbon productivity.
[0032] Additionally, diblock-silane coated proppants, with degradable linkage between the blocks, as illustrated in FIG. 1 , exploit the favorable properties of the variety of organosilanes described above. Diblock coated-proppants which are treated on the surface initially have a terminal hydrophobic coating to encourage efficient aqueous carrier-fluid flowback through the proppant pack and efficient proppant-carrying by the aqueous carrier-fluid. After shut in, degradation of the block-block connection, such as through an ester bond-hydrolysis, illustrated in FIG. 1 , or surface degradation leads to the coating of the proppants changing to a hydrophilic coating, which promotes efficient hydrocarbon production through the pack. Note also that the reaction byproducts of the ester degradation are a carboxylic acid (could break polysaccharide gel) and an organic alcohol, which could act as a breaker for a viscoelastic surfactant (VES) carrier fluid.
[0033] Finally, some systems may benefit from adding a stable diblock silane as a solution-phase additive to a fracturing fluid. This addition act as a wettability-modifier for the formation matrix adjacent to the fracture faces, through which aqueous fluid leakoff would occur. This additive may or may not necessarily be used in conjunction with coated proppants. Water-soluble diblock organosilane forms a permanent coating on the quartz grains of the matrix adjacent to the fracture during leakoff. Here, the initial hydrophobic coating of the formation allows for fast initial unloading of aqueous fracturing fluid that has leaked off into the formation. After sufficient flowback, a extended exposure to downhole conditions such as temperature (shut in) breaks the degradable diblock linkage leaving the matrix adjacent to the propped fracture preferentially water-wet for efficient hydrocarbon production into the fracture through the lifetime of production into the fracture.
[0034] In some embodiments, the permeability through a cross section of a portion of an agglomeration of the particulate is at least about 1 percent higher than if no organosilane is present and in some additional embodiments the permeability through a cross section of a portion of an agglomeration of the particulate is about 1 percent to about 50 percent higher than if no organosilane is present. Further, in some embodiments, the conductivity through a cross section of a portion of an agglomeration of the particulate is about 1 percent to about 50 percent higher than if no organosilane is present.
[0035] In some embodiments, at least about 50 percent of the wettability modification degrades upon exposure to a pH of about 7.5 or higher after at least about 2 hours. In some additional embodiments, at least about 50 percent of the wettability modification degrades upon exposure to a temperature of about 50° C. or higher after at least about 2 hours.
EXAMPLES
[0036] The following examples are presented to illustrate the preparation and properties of fluid systems, and should not be construed to limit the scope of the invention, unless otherwise expressly indicated in the appended claims. All percentages, concentrations, ratios, parts, etc. are by weight unless otherwise noted or apparent from the context of their use.
Example 1
[0037] (See FIG. 2 ): Contact angle measurements were carried out using a CAM101 contact angle instrument from KSV Instruments. For each contact angle measurement, the camera was calibrated using a 4 mm calibration ball. The water used to make droplets in the contact angle experiments was deionized water. All slides used in the contact angle measurements were 1×3 cm glass slides.
[0038] Prior to contact angle measurement or prior to coating (with organosilane), uncoated glass slides were rinsed sequentially with ethyl alcohol and deionized water. The slides were then stored on their side and were cured/dried in an oven set to 75° C. overnight (at least 12 hours).
[0039] For coating slides with organosilane, dry toluene was the solvent in which deposition occurred. Prior to the coating protocol, the toluene was stored over activated 4A molecular sieves. For the coating reaction, 300 mL of the dried toluene was combined with 2 weight percent organosilane (purchased from Sigma Aldrich or Gelest) and 1 weight percent triethylamine. The liquid components were combined and placed into a round-bottom-flask connected to a reflux-condenser. The glass slide was suspended in a wire cage fully submerged in the liquid reaction (so that no glass surfaces were flat against the flask) over a small stir-bar, stirring the reaction at 300 rpm. The reaction was maintained under a nitrogen-atmosphere (applied using laboratory nitrogen source) and the reaction was heated to reflux, greater than 112° C. for 6 hours. After the reaction, the glass slide was removed from the wire cage and was rinsed thoroughly with ethyl alcohol and water in sequence. After the rinsing protocol, the slide was cured overnight (>12 hours) in an oven at 75° C. After the overnight cure, the slide was sealed in a test tube and was stored in a dessicator.
[0040] Contact angle measurements on the coated surfaces show significantly higher contact angles to water compared to uncoated surfaces. This finding suggests that the coated surfaces are significantly more hydrophobic than the unmodified surface. The wettability of the treated-surface could be further modified through the spectrum of hydrophilicity/hydrophobicity through manipulation of the organic character in the organosilane used to treat the surface.
Example 2
[0041] (See FIGS. 2 and 3 ): Coating protocol for the proppants used in conductivity measurements for Example 2 are very similar to those used to coat the glass slides in Example 1. The proppant used in all conductivity measurements was a 20/40-mesh size Ottawa sand sample. The same batch of sieved 20/40 Ottawa sand was used in the blank tests (uncoated proppant) and in the coating protocols.
[0042] Uncoated proppant samples were rinsed sequentially with ethyl alcohol and deionized water on a vacuum filter. The proppant samples were then stored in a jar and were cured/dried in an oven set to 75° C. overnight (at least 12 hours).
[0043] For coating the Ottawa sand samples with organosilane, dry toluene was the solvent in which deposition would occur. Prior to the coating protocol, the toluene was stored over activated 4A molecular sieves. For the coating reaction, 200 mL of the dried toluene was combined with 2 weight percent organosilane (purchased from Sigma Aldrich or Gelest) and 1 weight percent triethylamine. The liquid components were combined and placed into a round-bottom-flask connected to a reflux-condenser. 70-80 grams of the rinsed Ottawa sand was poured into the reaction flask in addition to a stir-bar, stirring the liquid/proppant mixture at 300 rpm. The reaction was maintained under a nitrogen-atmosphere (applied using laboratory nitrogen source) and the reaction was heated to reflux greater than 112° C. for 6 hours. After the reaction, the reaction components were cooled to near room temperature. After cooling, the contents were vacuum-filtered and the proppant (caught on the filter was rinsed sequentially with more than 100 ml each of toluene, ethyl alcohol, and deionized water). After the rinsing protocol, the proppant was cured overnight (>12 hours) in an oven at 75° C. After the overnight cure, the proppant was sealed in ajar and was stored in a dessicator.
[0044] Conductivity Test (See FIGS. 3 and 4 ): 2% KCl (aq) and enough proppant to achieve 2 lb/ft 2 are confined against precision machined core faces 302 in a modified API conductivity cell 301 . Briefly, the proppant pack undergoes overnight shut-in (shut-in at temperature & closure stress) and next day flowback (to 2% KCl solution) while being subjected to closure stresses and temperatures necessary to simulate a packed hydraulic fracture at depth. After the proppant pack is leveled and assembled in the cell 301 , it is placed on the conductivity press 303 . The proppant pack is placed under a minimum of 250 psig hydrostatic pressure which will remain constant throughout the test. Proppant-pack heat-up rates are selected to achieve 80% of the desired temperature increase from the ambient temperature within thirty minutes. Bottomhole static temperature will be achieved within 50 minutes of initial heat-up, which is the final test temperature. All proppant samples (uncoated or coated) used 20/40 mesh Ottawa sand (common in fracturing) as base proppant.
[0045] Once the fracture is closed, the shut-in phase is initiated. The proppant-pack will be shut-in for 12 hours at interim closure stress and final temperature. The permeability recovery phase begins with pack-width measurements, temperature conditioning of flowback fluid and injection of 2% KCl (aq) flowback fluid into the cell. Aqueous flowback is initiated at a rate of 3.00 mL/min by flowing laterally through the proppant-pack while closure stress is raised to final closure stress (3000 psi) at 100 psi/min. Permeability is monitored for cell inlet flowback. Cell inlet flow 304 will continue until steady state differential pressure measurements 305 , 306 , 307 , 308 are attained, often at least for 2 hours. A steady state condition exists when at least ten pore volumes of cleanup fluid have flowed without a significant change in differential pressure readings. This is achieved when the permeability varies by less than 4% for a 60 minute period. Experiments 1 and 2 were carried out at 175° F., closure stress of 3000 psi, and back pressure of 250 psi.
[0000] Experimental parameters for Example 2:
[0046] Temperature: 175° F.
[0047] Closure Stress: 3,000 psi
[0048] Flow Rate (Q): 3 mL/min
[0049] Proppant loading: 2 lb/ft2
[0050] Proppant coated with 2-[methoxy(polyethyleneoxy)propyl]-trimethoxy silane[hydrophobic] leads to similar conductivity as that of uncoated sand. Here, pack of coated-proppant (1H,1H,2H,2H-perfluorodecyl silane) with the highest deionized water-contact angle has highest conductivity in a series of sand-blank experiments.
[0051] The conductivity and permeability measurements in FIG. 4 illustrate several trends. The proppant sample coated with 2-[methoxy(polyethyleneoxy)propyl]-trimethoxy silane shows very similar permeability and conductivity (under comparable conditions) to 2% KCl aqueous solution as uncoated sand. This indicates that the coating imparts a comparable hydrophilicity as the unmodified proppant or that the coating has degraded after exposure to the shut-in conditions at temperature and yields an unmodified proppant surface. In comparison, the hydrophobically-modified proppant coated with 1H,H,2H,2H-perfluorodecyltriethoxysilane yields significantly higher permeability and conductivity to 2% KCl (aq). This improved permeability can be attributed to the hydrophobic surface and resulting lower capillary pressure in the hydrophobic proppant. These results can be extrapolated to field scenarios, where the hydrophobic (perfluorodecyl) coatings could impart higher pack-permeability to facilitate recovery of any injected aqueous fluids.
Example 3
[0052] (See FIGS. 5-10 ) In this set of experiments, samples of coated proppants were aged in solutions of water at the specified pH values and the specified temperatures. These experiments were carried out to qualify the degradation behavior of a number of coatings that were prepared on proppant samples per the preparation described in Example 2. Periodically, samples of the coated solid were taken out of the varied-pH solutions and were analyzed with DRIFTS spectroscopy. The spectra were obtained on a Nicolet NEXUS FTIR spectrometer with a DRIFTS accessory (Manufactured by Thermo Electron Corporation). A portion of the DRIFTS spectrum attributable to alkyl stretches (2923 cm −1 ) of the organic chain of the organosilane coating was observed and the changes in peak area are attributed to coating degradation.
[0053] FIG. 5 is a plot of peak area as a function of days of an additional embodiment. The proppant used was coated with 3-aminopropyltriethoxysilane and the sample was aged at pH 10 at a temperature of 70° C. This hydrophilic coating (whose hydrophilicity is imparted by the amino moiety) undergoes rapid degradation at this moderate temperature and high pH.
[0054] FIG. 6 is a plot of peak area as a function of days of an additional embodiment. The proppant used was coated with 2-[methoxy-(polyethyleneoxy)propyl]-trimethoxysilane and the samples of coated proppant were aged at 70° C. in pH 6 and pH 10 solutions. This coating undergoes rapid degradation at both moderate and high pH and a temperature of about 70° C.
[0055] FIG. 7 is a plot of various DRIFTS spectra of the octadecyltrimethoxysilane-coated proppant (aged at pH 10 at 70° C. for varied periods of time) as a function of a wavenumber of an additional embodiment as illustrated by FIG. 8 . The presence of peak area at 2923 cm −1 indicates the presence of CH 2 groups on the proppant surface. In the current invention, this is imparted by the formation of a stable organosilane monolayer on the proppant surface. The persistence of the peak heights and peak area at 2923 cm −1 indicates that the coating is resistant to hydrolysis at this temperature and pH condition for extended periods of time.
[0056] FIG. 8 is a plot of peak area as a function of days of an additional embodiment. The proppant used was coated with octadecyltrimethoxysilane. These samples were held at 120° C. and 70° C. and a pH of about 10. The data in FIG. 7 was used to plot the trace of peak area here at 70° C. This coating, while hydrophobic, does undergo degradation only at the high temperature (120° C.) at this pH.
[0057] FIG. 9 is a plot of peak area as a function of days of an additional embodiment. The proppant used was coated with 1H,1H,2H,2H-perfluorodecyltriethoxysilane. This hydrophobic coating undergoes slow if any degradation at these aggressive conditions of high temperature and high pH.
[0058] The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. In particular, every range of values (of the form, “from about A to about B,” or, equivalently, “from approximately A to B,” or, equivalently, “from approximately A-B”) disclosed herein is to be understood as referring to the power set (the set of all subsets) of the respective range of values. Accordingly, the protection sought herein is as set forth in the claims below.
|
A method and composition for treating a subterranean formation with a fluid, including forming a fluid including a particulate and an organosilane with the chemical formula R n SiX 4-n, wherein n is equal to 1, 2, or 3, R is an organic functional group, and X is a halogen, alkoxy, or acetoxy group, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of a surface of the particulate or subterranean formation or both. A method and composition for treating a subterranean formation with a fluid including forming a fluid comprising a particulate and an organosilane, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of the proppant or surfaces or both, wherein the wettability modification degrades. A method and composition for producing hydrocarbon from a subterranean formation, including providing a wellbore in a subterranean formation, forming a fluid including a particulate and an organosilane with the chemical formula R n SiX 4-x, wherein n is equal to 1, 2, or 3, R is an organic functional group, and X is a halogen, alkoxy, or acetoxy group, introducing the fluid into the subterranean formation with exposed surfaces, modifying the wettability of a surface of the particulate or the subterranean formation or both, and producing hydrocarbon from the wellbore in the subterranean formation.
| 2
|
BACKGROUND OF THE INVENTION
To provide markers for airport runways and taxiways, it has become customary to employ light fixtures along the edges of runways and taxiways to facilitate guidance of aircraft during take-off, landing and taxiing operations. Conventional runway and taxiway elevated edge light fixtures typically consist of an upright support member or pedestal with a lamp assembly and prismatic globe mounted at its upper end. The support member is threadably or otherwise evgageable at its lower end with a base plate permanently mounted in or adjacent to the runway or taxiway. The globe provides a protective cover for the lamp assembly and can be optically configured as a lens to transmit light in a predetermined direction.
Such airport light fixtures are subjected to severe vibrations and high wind velocity, especially during aircraft operations. To preserve the desired directional alignment of these light fixtures, it is imperative that such fixtures be able to withstand such vibrations adn wind velocity without becoming tilted, misaligned or otherwise out of adjustment. However, for convenience and efficiency in the initial installation of such light fixtures and the subsequent correction of any misalignment which may occur, such fixtures should be readily adjustable externally while in place and without disassembly. To provide increased flexibility in leveling, such fixtures should be adjustably tiltable to plus or minus 7 degrees from horizontal at any point on a 360 degree horizontal plane. Moreover, such light fixtures should be provided with an optical globe which is firmly secured but conveniently removable for facilitating repair and/or replacement of the lamp, the lamp assembly, and the globe, as necessary.
As mentioned, precise angular orientation of the globe, i.e. position accuracy, is essential in such airport light fixtures. This is particularly so in bidirectional applications, in which horizontal aiming is critical. Convenience and efficiency in installation, repair and replacement of the globe may, thus, not be achieved at any sacrifice to position accuracy.
In order to provide the precise light pattern required, it is important that the lamp assembly of the light fixture be accurately and rigidly located. In the airport light fixture disclosed, for example, in U.S. Pat. No. 4,104,711, such precise location of the lamp assembly is achieved by mounting the electric lamp in an electrical socket which is supported by a mounting bracket which, in turn, is rigidly secured to the lamp base. Typically, such electrical sockets are secured by conventional nut and bolt type assembly hardware which is time-consuming to assemble and/or disassemble.
An additional problem arises from the fact that the design of electrical socket mounting brackets in conventional airport light fixtures has not adequately taken into account the applicable thermal considerations, and in particular, the need to minimize heat absorption by the bracket and heat transfer to the bracket.
An airport light fixture for mounting on a substantially cylindrical support column, comprising a lamp structure for providing illumination; an optical globe for covering the lamp and for directing the light emanating therefrom; and a base member for securely mounting the globe and the lamp structure in an adjustable, substantially upright position on the support column, the globe being releasably securable to the base member and substantially sealed over the lamp structure for protecting the lamp structure, the base member including, at its bottom, a mounting hub for mounting the base member on the upper end of the support column, the mounting hub including: (a) a substantially annular planar support surface positioned on the upper end of the support column when the base member is mounted thereon; (b) a substantially cylindrical collar depending downwardly from the planar support surface and having a plurality of leveling screws extending transversely therethrough for contacting the peripheral surface of the support column when the base member is mounted thereon for adjusting the tilt of the base member, as necessary, to obtain and securely maintain the desired vertical positioning of the globe; and (c) a plurality of guide ribs depending downwardly from the planar support surface and interiorly of the collar, the guide ribs being spaced around the support surface, and the interior surface of each of the ribs facing the support column when the base member is mounted thereon being equivalently tapered such that an imaginary surface passing through each of the individual surfaces is frustro-conically shaped and has its smaller diameter end adjacent the planar support surface, the smaller diameter being substantially equal to the outer diameter of the upper end of the support column for guiding the planar support surface of the mounting hub to the desired position above such upper end during mounting of the base member on the support column; the taper and positioning of each of the guide ribs, and the positioning of the collar and the leveling screws, being selected to permit adjustment of the tilt of the support member at any point on the circumference of the support column, as necessary to obtain the desired vertical positioning of the globe.
Additionally, a lamp socket mounting bracket comprising a pair of rigid, substantially upright, spaced apart support legs, each of the legs being secured at its bottom to the top portion of the base member in substantially parallel relationship at opposite sides thereof, each of the legs having at least two substantially upright stops projecting laterally therefrom in parallel relationship, the upper ends of each pair of stops being adjoined by a cross piece which forms a shelf for supporting the socket, the mounting bracket further having two, parallel, spaced apart retainer flanges connecting the upper ends of the legs and extending substantially orthogonally thereto for contacting the upper surface and the respective side surfaces of the socket when the socket is supported on the shelves for substantially preventing upward and lateral movement of the socket, respectively, each of the stops on one of the legs having an elongated surface inclined inwardly from the bottom, and the stops on the other of the legs each having similarly inclined elongated surfaces, the legs and the stops being situated such that, during upward insertion of the socket into the mounting bracket from below, the socket operatively engages the inclined surface of each of the stops, causing the legs to flex outwardly away from one another for permitting the socket to pass upwardly along and then beyond the inclined surfaces, the legs, the retainer flanges, and the junction therebetween being adapted to permit the legs to resiliently return to substantially their original positions, with the socket then resting on the shelves.
Also, a base member for mounting a globe and lamp assembly of an airport light fixture on a support column, including at least one resilient finger-like member having its free end normally extending upwardly a preselected distance above the globe support surface for engaging at least one of the globe tongues to deter or retard rotation of the globe on the base member in a rotational direction opposite to the one direction, the free end being displacable towards the globe support surface when the finger-like member is resiliently flexed downwardly for permitting desired rotation of the globe in such opposite direction.
SUMMARY OF THE INVENTION
The present invention, as embodied and broadly described herein, overcomes the above-noted problems and disadvantages of the prior art and achieves the objectives outlined above by providing an airport light fixture for mounting on a substantially cylindrical support column, comprising lamp means for providing illumination; an optical globe for covering the lamp means and for directing the light emanating therefrom; and a base member for securely mounting the globe and the lamp means in an adjustable, substantially upright position on the support column, the globe being releasably securable to the base member and substantially sealed over the lamp means for protecting the lamp means, the base member including, at its bottom, a mounting hub for mounting the base member on the upper end of the support column, the mounting hub including: (a) a substantially annular planar support surface positioned on the upper end of the support column when the base member is mounted thereon; (b) substantially cylindrical collar means depending downwardly from the planar support surface and having a plurality of leveling screws extending transversely therethrough for contacting the peripheral surface of the support column when the base member is mounted thereon for adjusting the tilt of the base member, as necessary, to obtain and securely maintain the desired vertical positioning of the globe; and (c) a plurality of guide ribs depending downwardly from the planar support surface and interiorly of the collar means, the guide ribs being spaced around the support surface, and the interior surface of each of the ribs facing the support column when the base member is mounted thereon being equivalently tapered such that an imaginary surface passing through each of the individual surfaces is frustro-conically shaped and has its smaller diameter end adjacent the planar support surface, the smaller diameter being substantially equal to the outer diameter of the upper end of the support column for guiding the planar support surface of the mounting hub to the desired position above such upper end during mounting of the base member on the support column; the taper and positioning of each of the guide ribs, and the positioning of the collar means and the leveling screws, being selected to permit adjustment of the tilt of the support member at any point on the circumference of the support column, as necessary, to obtain the desired vertical positioning of the globe. Typically, at least three leveling screws are provided, the screws being spaced around the support column, and at least three, and preferably six, guide ribs are provided, the ribs also being spaced around the support column.
As broadly embodied herein, the present invention further comprises a mounting bracket for mounting a lamp socket and a lamp received therein on a base member of an airport light fixture, the bracket comprising a pair of rigid, substantially upright, spaced apart support legs, each of the legs being secured at its bottom to the top portion of the base member in substantially parallel relationship at opposite sides thereof, each of the legs having at least two substantially upright stops projecting laterally therefrom in parallel relationship, the upper ends of each pair of stops being adjoined by a cross piece which forms a shelf for supporting the socket, the mounting bracket further having two, parallel, spaced apart retainer flanges connecting the upper ends of the legs and extending substantially orthogonally thereto for contacting the upper surface and the respective side surfaces of the socket when the socket is supported on the shelves for substantially preventing upward and lateral movement of the socket, respectively, each of the stops on one of the legs having an elongated surface inclined inwardly from the bottom, and the stops on the other of the legs each having similarly inclined elongated surfaces, the legs and the stops being situated such that, during upward insertion of the socket into the mounting bracket from below, the socket operatively engages the inclined surface of each of the stops, causing the legs to flex outwardly away from one another for permitting the socket to pass upwardly along and then beyond the inclined surfaces, the legs, the retainer flanges, and the junction therebetween being adapted to permit the legs to resiliently return to substantially their original positions, with the socket then resting on the shelves. The legs are typically spaced from the outer periphery of the socket by spacer ridges situated on the inner surface of each leg.
Broadly, the invention also comprises a base member for mounting a globe and lamp assembly of an airport light fixture on a support column, comprising a mounting hub for mounting the base member on the support column; a generally circular globe support surface having a plurality of peripherally spaced flanges providing inwardly facing channels, the globe having a generally circular base provided with a plurality of peripherally spaced outwardly projecting tongues for rotatable assembly into the channels to secure the globe to the base member, at least one of the flanges having a projection for engaging at least one of the tongues to limit rotation of the globe on the base member in one direction; and at least one resilient finger-like member having its free end normally extending upwardly a preselected distance above the globe support surface for engaging at least one of the globe tongues to deter or retard rotation of the globe on the base member in a rotational direction opposite to the one direction, the free end being displacable towards the globe support surface when the finger-like member is resiliently flexed downwardly for permitting desired rotation of the globe in such opposite direction.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only, and are not intended to be restrictive of the invention as claimed.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one embodiment of the invention and, together with the description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic vertical section view of an airport light fixture constructed in accordance with the present invention;
FIG. 2 is a plan view of the embodiment shown in FIG. 1 in partial cut-away form to reveal details of its construction;
FIG. 3 is a partial diagrammatic vertical section view of the airport light fixture base member of the present invention showing the details of construction of the mounting hub;
FIG. 4 is a partial cross-sectional view of the airport light fixture base member of the present invention taken along line 4--4 of FIG. 2, showing the resilient finger-like member for providing retention of the light fixture globe on the base member; and
FIG. 5 is a diagrammatic partial vertical section view of an airport light fixture support column and a coupling therefor constructed in accordance with a further embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference will now be made in detail to the presently preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings.
The presently preferred embodiment of the airport runway/taxiway elevated edge light fixture of the present invention is shown in FIG. 1, and is represented generally by the numeral 10. This fixture includes lamp means 20; a prismatic globe 30 for covering the lamp means and for directing the light emanating therefrom in the desired direction; a substantially cylindrical support column 40; and a base member 50 (globe support) for securely mounting globe 30 and lamp means 20 in an adjustable, substantially upright position on support column 40. Base member 50 includes, at its bottom, a mounting hub 51 for mounting the base member on the upper end of support column 40.
Referring to FIGS. 1-3, mounting hub 51 includes a generally planar support surface 52 which extends annularly and rests on the upper end 41 of support column 40 when base member 50 is mounted on the support column. A generally cylindrical collar 53 extends downwardly from support surface 52 so as to surround the upper end 41 of support column 40. Typically, collar 53 is between 1 and 3 inches long, the outer diameter of upper end 41 is on the order of 1 inch, and the inner diameter of collar 53 is about 11/2 inches.
Leveling set screws 54 pass through holes 55 which extend transversely through collar 53. Preferably, at least three holes 55 are spaced equidistantly around collar 53, with a leveling screw 54 passing through each such hole. It is preferable, for strengthening purposes, to provide collar 53 with regions of increased thickness immediately surrounding holes 55, as shown. The inner ends of leveling screws 54 firmly contact the peripheral surface of support column 40 upon tightening the screws, so as to provide positive and rigid fastening of base member 50 to support column 40. The degree of tightening of each leveling screw 54 determines the horizontal tilt of base member 50. Thus, the tilt of base member 50 may be controlled at any point on the circumference of support column 40, as necessary, to obtain the desired leveling of base member 50 and attached globe 30.
In practice, base member 50 and attached globe 30 are leveled to the desired position through the use of a conventional leveling device, as well known in the art. The desired position is maintained by individually adjusting the degree of tightening of each of the three leveling screws 54 as necessary. As can be seen, leveling screws 54 are readily accessible externally for easy, rapid, and efficient adjustment.
A plurality of guide ribs 56 (flutes) depends downwardly from planar support surface 52 on the inner circumference of mounting hub 51. Guide ribs 56 are situated interiorly of collar 53 and typically are between about 1/4 inch and about 2 inches long. Preferably, at least three, and more preferably, six guide ribs 56 are spaced around support surface 52. The interior surface 57 of each rib 56 is equivalently tapered (see FIGS. 1 and 3) such that an imaginary surface passing through each of said surfaces 57 is frustro-conically shaped, with its smaller diameter end adjacent support surface 52 when base member 50 is mounted on support column 40. Such smaller diameter is preferably substantially equal to the outer diameter of the upper end 41 of support column 40, and the interior surface of each rib 56 is preferably tapered from vertical at a slope of between about 5 degrees and about 10 degrees, and most preferably at about 8 degrees. As a result of the aforesaid construction of guide ribs 56, they serve to guide substantially planar support surface 52 of mounting hub 51 to the desired position above the upper end 41 of support column 40 during the mounting of base member 50 on the support column. That is, the six tapered guide ribs 56 on the inner circumference of mounting hub 51 provide, at their base portions adjoining planar support surface 52, the minimum clearance required to centrally locate support column 40 beneath base member 50. Preferably, the tapered surfaces and the positioning of guide ribs 56, as well as the arrangement of collar 53 and leveling screws 54, are selected to permit adjustment of the tilt of base member 50 to plus or minus 7 degrees from horizontal at any point on a 360 degree horizontal plane for leveling purposes, while still maintaining centering at the top of support column 40.
As an alternative to providing six separate tapered guide ribs 56, the mounting hub 51 may be constructed with a single tapered guide ring having an inner profile (surface) equivalent to the profile of interior surface 57, but extending the entire 360° of the inner circumference of mounting hub 51.
In the preferred embodiment of the invention, base member 50, including mounting hub 51, is of one-piece rigid non-metallic construction, preferably constructed of polymeric materials, or derivatives thereof, having suitable physical properties for the desired application and being moldable by injection or compression molding, or another appropriate molding process. Examples of such polymeric materials include, without limitation, thermosetting and thermoplastic resins and mixtures thereof, such as, for example, the following resins: polycarbonate, polyester, phenol, urea, furfural, allyl, epoxy, silicon, borosilicone, carbosilicone, and mixtures thereof, with one or more of the following reinforcing fillers: glass fibers, mica and asbestos.
Preferably, base member 50 is constructed of a material which will provide the following base member property characteristics (a) U.L.® Temperature Index Rating of at least about 102° C.; (b) Izod Impact Strength (notched) of at least about 2.0 ft. lb./in.; (c) Tensile Strength of about 23,000 psi; (d) Flexural Strength of about 37,000 psi; and (e) Compressive Strength of about 25,000 psi.
Referring to FIGS. 1 and 2, base member 50 is typically circular, when viewed from above, and globe 30 typically includes a circular base portion having a flat surface 31 for mating with a corresponding flat upper surface 58 of base member 50. As shown in FIG. 1, a static seal 65 of round, square or other cross section is preferably provided between such mating surfaces 31 and 58 for providing a fluid-tight seal to protect lamp means 20 against dust, wind, rain and other weather-related damage.
As shown in FIG. 1, globe 30 is preferably dome-shaped in configuration. It can be made of transparent, colored material such as, for example, glass or polymeric material, so as to emit only light of the desired color. The surface of globe 30 is preferably configured so as to provide the desired optical properties, e.g., distributing light in particular directions. As shown in FIG. 2, globe 30 preferably includes three outwardly projecting tongues 32, 33, 34 at its base portion. One of the tongues, e.g., tongue 32, is preferably substantially wider than the others to facilitate the desired orientation of globe 30 on base member 50.
Referring to FIGS. 1 and 2, base member 50 preferably includes three upstanding flanges 59, 60, 61 spaced about the periphery of its generally circular top surface 58. The flanges are elongated and extend tangentially along the periphery of the base member. In addition, flanges 59, 60, 61 have radially inward facing channels for receiving tongues 32, 33, 34, respectively, of globe 30. In the assembly of globe 30 to base member 50, the globe is placed on the top surface 58 of the base member with its tongues 32, 33, 34 located in the spaces between flanges 59, 60, 61, respectively, and globe 30 is then rotated in a clockwise direction, as viewed in FIG. 2, to move tongues 32, 33, 34 into the corresponding channels defined by flanges 59, 60, 61, respectively. Preferably, a stop is provided on at least one of the flanges 59, 60, 61 to limit rotational movement of at least one of the tongues in its channel. As shown in FIG. 2, flange 61 may, for example, include a stop 62 extending radially inward to block clockwise movement of tongue 34 beyond flange 61.
As broadly embodied herein, the present invention further comprises a light fixture base member 50 having at least one vertically resilient finger-like member 70 (see FIGS. 2 and 4) having a free end 71 normally extending above base member top surface 58. When tongues 32, 33, 34 are located in the corresponding channels defined by flanges 59, 60, 61, respectively, the free end 71 is situated such that tongue 32 is deterred or retarded from rotating counter-clockwise, thus deterring or retarding rotation of globe 30 in the counter-clockwise direction.
Removal of globe 30 from base member 50 is readily accomplished by manually applying a downward force to finger-like member 70 to lower it a sufficient distance to permit counterclockwise rotation of the globe to a point where tongues 32, 33, 34 are disengaged from flanges 59, 60, 61, so that the globe may be lifted off base member 50. Alternatively, base member 50, finger-like member 70, and globe 30 may be designed such that counter-clockwise rotation of the globe will cause a force to be transmitted through the globe to displace the finger-like member downwardly to permit removal of the globe.
Globe 30 is mounted on base member 50 by placing the globe on the base member top surface 58, as described above, and applying a downward force to finger-like member 70 to depress it to substantially the same level as top surface 58 by simply exerting downward pressure on globe 30 and then rotating the globe clockwise as previously discussed. At the point when globe tongue 32 rotates clockwise sufficiently to disengage from above the free end 71 of finger-like member 70, the free end will resiliently return to nearly its original position so as to interpose the edge of the globe tongue.
The above-described retarding mechanism permits precise angular orientation and facilitates removal and replacement of globe 30, while maintaining sufficient position accuracy. This is important in bidirectional applications in which horizontal aiming is required.
Preferably, finger-like member 70 is integral with the remainder of base member 50, with both being of one-piece resilient non-metallic construction.
As an alternative to the aforementioned globe snap lock feature, proper location of globe 30 on base member 50 may be optionally maintained by assembling a retaining screw 72 vertically into a hole provided on the side of base member flange 61 opposite stop 62 (or in an equivalent side of flanges 59 or 60) after globe 30 has been fully rotated to the desired installed position. Similarly to finger-like member 70, screw 72 precludes counter-clockwise rotation of globe 30 by blocking the path through which the globe tongue must travel, thereby assuring proper positioning of the globe.
As embodied herein, and referring to FIGS. 1 and 2, the lamp means 20 includes an electrical lamp 21 provided with prongs (not shown) and an electrical socket 22 for receiving the prongs. Socket 22 is securely mounted on a mounting bracket 23 secured by two self-tapping binding screws 24 at its opposite ends to mounting bracket supports 66 formed on the top portion of base member 50. Mounting bracket supports 66 are situated inside globe support surface 58. A pair of electrical leads 80 extends downwardly from socket 22 through a grommet 81 provided in a central opening in the annular mounting hub support surface 52 of base member 50. The leads 80 extend further downwardly through the hollow interiors of support column 40 and a suitable conventional coupling 82. As shown in FIG. 1, coupling 82 preferably comprises a tubular frangible coupling which serves to securely support support column 40 by means of a securing screw 83 and to facilitate connection of leads 80 to an external power line (not shown). The light fixture is installed by connecting the bottom end of connector 82 to a base plate, a mounting stake, or the like, in the conventional manner. Preferably, coupling 82 and support column 40 are constructed of either metal or a nonmetallic material suitable for this application.
As embodied herein, mounting bracket 23 of the present invention includes a pair of rigid, substantially upright and parallel, spaced apart legs 25. Each of the legs 25 is provided with at least two substantially upright stops 26 projecting laterally therefrom in substantially parallel relationship. The upper ends of each pair of stops 26 are adjoined by a cross piece 27 which forms a shelf 27 for supporting socket 22.
Mounting bracket 23 further includes two parallel, spaced apart retainer flanges 28 connecting the upper ends of legs 25 and extending substantially orthogonally thereto for contacting the upper surface and the respective side surfaces of socket 22 when the socket is supported on shelves 27 for substantially preventing upward and lateral movement of socket 22, respectively. Retainer flanges 28 preferably have a right angle contour (FIGS. 1 and 2) to complementarily overlap the sides of socket 22. The socket is preferably rectangular in form, when viewed from its sides.
Each of said stops 26 has an elongated surface 26' inclined inwardly from the bottom. In accordance with the invention, stops 26 and legs 25 are situated such that, during the upward insertion of socket 22 into mounting bracket 23 from below, socket 22 operatively engages the inclined surface 26' of each stop 26, which causes legs 25 to flex outwardly away from one another for permitting socket 22 to pass upwardly along and then beyond inclined surfaces 26'. Legs 23, retainer flanges 28 and the junction therebetween are constructed so as to permit legs 23 to resiliently return to their original positions, with socket 22 then resting on shelves 27. This is accomplished, for example, by constructing bracket member 23 as a rigid, one piece nonmetallic structure, using, for example, polymeric materials, or derivatives thereof, with one or more reinforcing fillers. The bracket member 23 is preferably injection molded, compression molded, extruded, pressed, or formed through a sequence of these processes to a thickness within the range of from about 0.02 to about 0.09 inch, more preferably on the order of about 0.06 inch thick.
Preferably, bracket member 23 is constructed of a material which will provide the following bracket member property characteristics: (a) U.L.® Temperature Index Rating of at least about 150° C.; (b) Izod Impact Strength (notched) of at least about 1.4 ft. lb./in.; (c) Tensile Strength of about 19,000 psi; (d) Flexural Strength of about 26,800 psi; and (e) Compressive Strength of about 21,000 psi.
Preferably, the surface of each leg 25 and each retainer flange 28 which faces socket 22 includes at least one inwardly projecting, elongated ridge 29 for contacting socket 22 when it is mounted on mounting bracket 23. Ridge 29, by providing substantially point contact with socket 22, serves to position socket 22 on mounting bracket 23, while also facilitating ventilation around the socket and the bracket to aid in cooling them. Moreover, each leg 25 preferably includes at least two ribs 25' extending outwardly from its base and terminating in an integral tongue portion 25" for securing mounting bracket 23 on opposite sides of the top portion of base member 50.
The lamp socket mounting bracket 23 of the present invention, as described above, thus incorporates a resilient socket mounting feature that eliminates conventional nut and bolt type assembly hardware and facilitates assembly of the light fixture, as well as providing precise location of the parts involved. The mounting bracket provides both a minimum amount of horizontal cross-sectional surface area exposed to the radiant lumens emanating from the lamp for minimum heat absorption and point contact location of the socket for minimizing conductive heat transfer, thus maximizing its cooling properties. Furthermore, the design and assembly geometry assure accurate and rigid location of the lamp socket, as required to provide the precise light pattern necessary in airport light fixtures.
It will be apparent to those skilled in the art that various modifications and variations can be made in the airport light fixture of the present invention without departing from the scope or spirit of the invention. For example, the above-described locating and leveling features of mounting hub 51 may optionally be substituted and incorporated into coupling 82A, rather than mounting hub 51, as shown in FIG. 5 (features analogous to those shown in FIG. 1 bear the same reference numerals plus the suffix "A"). In such an embodiment, the inside diameter of mounting hub 51 will be uniform and will be similar to that of coupling 82 of FIG. 1. Mounting hub 51 will then require only a single binding screw to secure the hub to the upper end of support column 40, while three leveling screws 54A will be required on coupling 82A.
Thus, it is intended that the present invention cover such modifications and variations of this invention, provided they come within the scope of the appended claims and their equivalents.
|
The present invention relates to an airport light fixture, and more particularly to an improved light fixture which finds particular utility as a runway or taxiway elevated edge light.
| 5
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] The present invention relates in general to cannulas and in particular to an infiltration cannula that allows for intermittent infiltration of fluids, such as a local anesthetic.
[0004] Many medical procedures require infiltration of fluids, such as a local anesthetic. One method of infiltration of local anesthetic is via an infiltration cannula. Infiltrators currently on the market are known as sprinkler-tip or Klein (the present applicant) needle infiltrators. These cannulas are constructed out of a rigid stainless steel and have one or more apertures, which are typically round or oval, and are distributed about the distal end of the cannula. The apertures are distributed over about 15% to 25% or less than 5.0 cm. of the distal end of the cannula needle. These traditional infiltration cannulas are intended to be inserted through a small incision in the patient's skin and then moved in and out through the subcutaneous tissue while a dilute solution of local anesthetic (or other pharmaceutical solution) is ejected through the distal apertures. Such infiltrators typically have a blunt tip and require the placement of a small hole (made by a one mm skin-biopsy punch or a small surgical blade) through which the blunt tipped cannula can be passed. The piston-like in and out motion of the cannula causes the patient discomfort.
[0005] Another method of fluid insertion is via a peripherally inserted central catheter, also called a PICC line comprising an elongate plastic tube that is placed inside a vein of the patient. PICC lines are typically used for procedures requiring delivery of fluids over a prolonged period of time. For example, a PICC line may be used when a patient needs to receive intravenous (IV) fluids. such as medication or nutrients over a prolonged period of time, such as a week or more.
[0006] The On-Q® Pain Management System marketed by I-Flow® Corporation employs a PICC line type system for continuously providing local anesthetic. This system provides prolonged local anesthesia by means of an elastomer (elastic container) device that continuously infiltrates a solution of local anesthesia over many hours. The On-Q® device is a long soft flexible tube with many small holes arranged along a significant portion of the tube. The On-Q® device is designed to be positioned within a surgical wound at the time of surgery; after the surgical wound is closed the On-Q® device permits slow steady infiltration of a local anesthetic solution into the wound, thereby attenuating post-operative pain. The On-Q® device cannot be inserted through a tiny hole in the skin into subcutaneous tissue. Thus there is a need for a simple device that can permit the direct percutaneous insertion of a multi-holed infiltration cannula into subcutaneous tissue for the localized delivery of medications such as local anesthetics, chemotherapeutic agents, or crystalloids for parenteral hydration.
[0007] Traditional techniques for subcutaneous injection of local anesthetic solutions use a high-concentration/low-volume of local anesthetic. This is associated with a rapid systemic absorption of the local anesthetic. In order to achieve a prolonged local anesthetic effect, the traditional techniques for using local anesthetics necessitate either frequent repeated injections or slow continuous subcutaneous infusion of the local anesthetic. As described above, repeated injections or piston-like movement of the cannula causes patient discomfort. Slow continuous infiltration may not be desirable in certain situations. Furthermore, continuous infiltrations restrict patient movement for extended periods of time which also cause the patient discomfort. Thus, there is a need for a system for infiltration of a local anesthetic into subcutaneous tissue which decreases patient discomfort, and allows prolonged local anesthesia.
BRIEF SUMMARY OF THE INVENTION
[0008] An infiltration cannula and method of using the infiltration cannula during an infiltration procedure are disclosed herein. The infiltration cannula includes: a tubular needle and a hub. The tubular needle has a proximal end and a distal end. The tubular needle also has a plurality of apertures disposed in a pattern about the distal end. The apertures are configured to infiltrate fluid into the subcutaneous tissue of a patient. The hub is configured to be held by a person performing the infiltration procedure. The hub has a first end and an opposing second end. The first end is attached to the proximal end of the tubular needle and the second end includes a connector configured to connect to an input source for receiving the fluid to be infiltrated into the subcutaneous tissue of the patient. The fluid flows from the connector, through the hub and into the tubular needle.
[0009] The tubular needle may be manufactured of stainless steel or plastic.
[0010] The apertures may be arranged in a helical pattern or in a spiral pattern.
[0011] The apertures may be distributed over about 33% to about 90% of the distal end of the tubular needle.
[0012] The apertures may be round or oval.
[0013] The fluid may be a local anesthetic.
[0014] The infiltration procedure may be performed in conjunction with a liposuction procedure.
[0015] A method of infiltrating fluid into subcutaneous tissue of a patient using an infiltration cannula, such as the one described above may include the following steps: (1) inserting an infiltration cannula through a patient's skin and into the subcutaneous tissue of the patient at a desired site; (2) receiving fluid from the fluid source via the connector; (3) transporting the fluid from the connector through the hub and into the tubular needle; and (4) ejecting the fluid from the tubular needle into the subcutaneous tissue of the patient via the apertures. The infiltration cannula used in performing the method includes: a connector for receiving the fluid from a fluid source, a hub in communication with the connector and a tubular needle in communication with the hub. The tubular needle has a plurality of apertures disposed in a pattern about a distal end. The apertures are configured to infiltrate the fluid into the subcutaneous the tissue of the patient.
[0016] Steps (1)-(4) may be repeated intermittently. The steps may be repeated at intervals between about eight hours and twelve hours.
[0017] After the desired amount of fluid has been infiltrated at a given site, the infiltration cannula is removed.
[0018] The infiltration cannula may be inserted at a new site.
[0019] Multiple infiltration cannulas (e.g., two) may be used simultaneously. Use of multiple infiltration cannulas prevents disruption of the method infiltration process when one infiltration cannula is removed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] These as well as other features of the present invention will become more apparent upon reference to the drawings wherein:
[0021] FIG. 1 is a side elevation view of a stainless steel infiltration cannula shown inserted in subcutaneous tissue shown in partial cross section;
[0022] FIG. 2 is a section view of the infiltration cannula shown in FIG. 1 ;
[0023] FIG. 3 is a side elevation view of a plastic infiltration cannula shown inserted in subcutaneous tissue shown in partial cross section;
[0024] FIG. 4 is an exploded view of the infiltration cannula shown in FIG. 3 ; and
[0025] FIG. 5 is a flow diagram illustrating an exemplary procedure for using an infiltration cannula such as the one shown in FIG. 1 or the one shown in FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
[0026] As described in further detail below, the present invention takes advantage of the tumescent technique in order to provide intermittent infiltration of local anesthetic. The present invention results in a significant decrease in patient discomfort due to the elimination of the piston-like in and out motion of the cannula. Once the cannula is in place, there is no need to push the cannula through the tissue in order to deliver the fluid to a wide area. Using the tumescent technique, the time needed in order to complete the infiltration of a targeted anatomic area is reduced to nearly half of the time required when using traditional prior art cannulas. The device and method described herein can use multiple (e.g., two) infiltration cannulas simultaneously. While one cannula is actively dispersing tumescent fluid into the subcutaneous tissue, the surgeon can reposition a second infiltration cannula. This allows the infiltration process to proceed without interruption, whereas prior art techniques of infiltration must be ceased each time the cannula is withdrawn from the skin and re-inserted into another direction.
[0027] The tumescent technique was discovered by Jeffrey Alan Klein, M.D. (the applicant) in 1985. Dr. Klein first published a description of the tumescent technique in 1987 when he described the use of dilute lidocaine and epinephrine to permit liposuction totally by local anesthesia. A detailed description of the tumescent technique has not been published in anesthesiology literature, and therefore, the unique benefits of the tumescent technique are not well recognized by anesthesiologists.
[0028] The tumescent technique is a drug delivery system that takes advantage of a recently discovered reservoir effect of injecting a relatively large volume of relatively dilute solution of a drug into the subcutaneous tissue.
[0029] The present invention takes advantage of the tumescent reservoir phenomenon. It has many novel applications, an example of which is pain management. This technique eliminates the need for a continuous infiltration of local anesthetic and allows for intermittent injections. In exemplary embodiments, the intermittent injections are administered every eight to twelve hours.
[0030] With the tumescent technique, a large volume of dilute solution of local anesthesia and epinephrine is injected into the subcutaneous space resulting in a large bolus (or reservoir) of solution. The profound vasoconstrictive effect (shrinking of the capillaries) of the dilute epinephrine produces a dramatic delay in the systemic absorption of the local anesthetic, which prolongs the anesthetic effects of tumescent anesthesia for eight to sixteen times longer than traditional techniques.
[0031] Referring now to the drawings wherein the showings are for purposes of illustrating preferred embodiments of the present invention only, and not for purposes of limiting the same, FIGS. 1 and 2 illustrate a stainless steel (reusable) infiltration cannula 10 and FIGS. 3-4 illustrate a (single use) plastic infiltration cannula 30 . The cannula 10 , 30 can be inserted under the skin 52 and into the subcutaneous tissue 50 and tumescent local anesthesia can be infiltrated once every eight to twelve hours.
[0032] Stainless steel infiltration cannulas 10 , such as the one shown in FIGS. 1 and 2 , are precision high quality and reusable. These cannulas can be used to provide tumescent local anesthesia for surgical procedures, such as liposuction, which require tumescent local anesthesia over a relatively large area.
[0033] The cannula 10 includes a tubular needle portion 12 which has a proximal end 14 and a distal end 16 . The proximal end 14 of the tubular needle 12 is attached to a hub 20 that is used by the anesthesiologist or surgeon to hold the cannula 10 during the infiltration procedure. The hub 20 is connected to the tubular needle 12 at a first end 22 and has a connector 24 , such as a luer lock, at an opposing second end. The connector 24 is connected to a fluid source, such as tubing connected to an IV bag. Fluid enters the cannula 10 via the connector 24 .
[0034] In exemplary embodiments, the tip at the distal end 16 is closed. The local anesthetic is infiltrated into the patient via apertures 18 located proximate the distal end 16 of the tubular needle 12 of the cannula 10 . In exemplary embodiments, the apertures 18 are disposed along the distal end 16 of the cannula 10 in a spiral or helical pattern and are distributed over the distal 33% to 90% of the tubular needle 12 of the cannula 10 . For example, if the length of the tubular needle D is 15 cm and the apertures 18 at the distal end 16 cover a length d 1 of 5 cm, the pattern of apertures of the cannula 10 are distributed over 33% of the tubular needle 12 of the cannula 10 .
[0035] The proximal portion 14 of the cannula 10 is devoid of apertures in order to prevent fluid from leaking out of the cannula insertion site in the skin.
[0036] Plastic infiltration cannulas 30 , such as the one shown in FIGS. 3 and 4 , are single use cannulas and can be used in one of several unique ways. First, an anesthesiologist or surgeon can insert an infiltration cannula 30 with stylet 46 into the subcutaneous tissue 50 , remove the stylet 46 , then attach an IV tubing to the infiltrator and inject tumescent local anesthesia into the targeted area without subsequent repositioning of the infiltration cannula 30 . The plastic flexible nature of the tubular needle 32 of the disposable plastic cannula 30 allows the patient to move or change position of the body without risk of injury that might result if a patient moves while a rigid steel cannula is inserted. Preferably, the stylet 46 is metal, e.g., stainless steel. The plastic cannula 30 can be blunt-tipped with the metal stylet tip 48 covered by the rounded tip 39 of the plastic cannula 30 . Alternatively, the plastic cannula 30 can be open-ended with the stylet 46 extending a short distance past the end 39 of the plastic cannula. 30 . In the case of an open-ended cannula, the metal stylet 46 can be either blunt-tipped (requiring a skin incision to permit insertion into the subcutaneous space), or sharp-tipped (permitting the cannula to be inserted directly through the skin and into the subcutaneous space without requiring a preparatory skin incision.
[0037] The plastic cannula shown in FIGS. 3 and 4 is similar to an IV catheter except the sharp hollow stylet used for the insertion of an IV catheter is replaced by a solid obturator/stylet 46 that can be either sharp or blunt tipped. Except for the removable stylet 46 , the plastic cannula 30 is similar to the stainless steel cannula 10 shown in FIGS. 1 and 2 and described above. The plastic cannula 30 includes a flexible tubular needle 32 having a proximal end 34 and a distal end 36 . The distal end has apertures 38 and the proximal end 34 is devoid of apertures. As stated above, in exemplary embodiments, the pattern of apertures 38 in the cannula 30 are distributed over the distal 33% to 90% of the tubular needle 32 of the cannula 30 . For example, if the tubular needle 32 of cannula 30 shown in FIGS. 3 and 4 has a length D of 15 cm and the pattern of apertures are distributed over a length d 1 of 13.5 cm, then the apertures 38 are distributed over 90% of the cannula.
[0038] A typical infiltration cannula 10 , 30 might be 20, 18, 16 or 14 gauge (i.e., 20, 18, 16 or 14 cm in length) with small apertures 18 , 38 placed every 5 mm d 2 along the cannula in a spiral or helical pattern. It will be appreciated that the dimensions used herein are exemplary and that the cannula dimensions, range of gauge, relative size shape and pattern of apertures can vary greatly depending upon clinical preference.
[0039] The proximal end 34 of the tubular needle 32 shown in FIGS. 3 and 4 is attached to a hub 40 that is used by the anesthesiologist or surgeon to hold the cannula 30 during the infiltration procedure. The hub 40 is connected to the tubular needle 32 at a first end 42 and has a connector 44 at an opposing second end. The connector 44 is connected to a fluid source. As described above and shown in FIG. 4 , the stylet 46 can be inserted and removed from the cannula 30 .
[0040] Infiltration using a plastic infiltration cannula 30 , such as the one shown in FIGS. 3 and 4 , can be accomplished using an infiltration pump. Alternatively, the force of gravity could be used to push the tumescent fluid into the tissues by hanging a reservoir plastic bag of tumescent local anesthesia (or other dilute drug, such as a chemotherapeutic agent or antibiotics) on an IV pole and connecting bag to the infiltration cannula by an IV line.
[0041] Another application is the injection of tumescent local anesthesia into a localized area through which a surgeon plans to make a surgical incision. The effects of vasoconstriction within the tumesced tissue minimizes surgical bleeding. The effects of tumescent local anesthesia produce prolonged post operative analgesia and also reduce the risk of surgical wound infections.
[0042] Yet another application is to provide an easily accessible route for systemic administration of crystalloid fluids/electrolytes for systemic hydration or for other types of drug therapy. Potential clinical applications include emergency resuscitation with systemic fluids in situations where insertion of an IV catheter into a vein cannot be readily achieved. Examples of situations where emergency access for intravenous delivery of fluids might not be possible include acute trauma or burn wound in civilian or military situations. Another application might be the emergency treatment of dehydration associated with prolonged vomiting or diarrhea (e.g., epidemic cholera) such as among pediatric patients in rural (e.g., third world) settings. A subcutaneous infiltration catheter can easily be placed by a layman, whereas inserting an IV catheter into a patient that is severely dehydrated can be difficult even for a skilled physician. Delivery of systemic fluids by subcutaneous infiltration is safer in a zero gravity situation (for example, the Space Station). The addition of a small amount of capillary vasodilator (e.g., methylnicotinamide) to the subcutaneous fluid can be used to accelerate the systemic absorption of the fluid or drug into the intravascular space.
[0043] The cannula 10 , 30 is intended to be inserted far enough through the skin 52 so that all of the apertures 18 , 38 are within the fat 50 of the patient. Once the cannula 10 , 30 is properly positioned, it can remain stationary while the local anesthetic (or other pharmaceutical) solution is injected.
[0044] After one portion of the targeted area has been tumesced, the infiltration is briefly terminated (either by turning off the pump or by clamping the IV tubing) while the cannula 10 , 30 is repositioned into another area of the subcutaneous tissue. The infiltration is then restarted with the cannula stationary in its new position.
[0045] The infiltrator 10 , 30 can also be used in the traditional mode whereby the cannula 10 , 30 is moved through the targeted tissue while the fluid is simultaneously pumped through the cannula 10 , 30 and into the subcutaneous tissue 50 .
[0046] Another unique aspect of the tumescent technique's reservoir effect is that one can conveniently achieve a long slow steady absorption of a drug delivered to the subcutaneous space 50 using periodic injections of a tumescent solution. In certain situations, using a slow IV infusion, the alternative technique, can achieve a slow systemic absorption of a drug but may be difficult, require greater clinical expertise, be more expensive, and therefore, less practical than the technique described herein.
[0047] FIG. 5 is a flow diagram illustrating steps performed in an exemplary infiltration procedure using a cannula 10 , 30 such as the one shown in FIGS. 1 and 2 or the one shown in FIGS. 3 and 4 , respectively. The procedure begins by inserting the tubular needle 12 , 32 of the infiltration cannula 10 , 30 into a desired subcutaneous tissue site 50 , e.g., via an incision in the patient's skin 52 (block 100 ). Fluid is then transported from the fluid source (e.g., an IV bag) into the cannula 10 , 30 via the connector 24 , 44 that is connected to the fluid source. The fluid is transported from the connector 24 , 44 through the hub 20 , 40 and into the tubular needle 12 , 32 (block 102 ). The fluid is then ejected from the cannula 10 , 30 into the subcutaneous tissue 50 of the patient via the apertures 18 , 38 at the distal end 16 , 36 of the tubular needle 12 , 34 of the cannula 10 , 30 (block. 104 ).
[0048] The fluid is transported (block 102 ) and ejected (block 104 ) until infiltration at the current site is completed (yes in decision block 106 ). The fluid can be injected into multiple sites in order to distribute the solution over a greater area.
[0049] Infiltration at a particular site may be deemed complete upon emptying of the fluid source or based on the anesthesiologist or surgeon's decision to stop the infiltration at the current site. After one portion of the targeted area has been tumesced, the infiltration can be briefly terminated (either by turning off the pump or by clamping the IV tubing) while the cannula 10 , 30 is repositioned into another area of the subcutaneous tissue. The infiltration is then restarted with the cannula stationary in its new position. If the infiltration at a site is complete (yes in decision block 106 ), the cannula is removed from the current site (block 108 ). If the infiltration at the current site is not complete (no in decision block 106 ), fluid is transported from the fluid source (block 102 ) and ejected into the subcutaneous tissue (block 104 ) until infiltration at the site is complete (yes in decision block 106 ).
[0050] If infiltration is complete at the current site (yes in decision block 106 ) but infiltration is not complete (no in decision block 110 ), the tubular needle 12 , 32 of the infiltration cannula 10 , 30 is inserted into a new area of subcutaneous tissue 50 . The process described above is performed until the infiltration process is complete (yes in decision block 110 ). This process can be repeated intermittently, for example every eight to twelve hours as described above.
[0051] As described above, multiple infiltration cannulas (e.g., can be used at once). Thus, a second cannula can be inserted (block 100 ) at the same time as a first cannula is being removed (block 108 ). Thus, the infiltration process need not be interrupted in order to reposition a single cannula.
[0052] Additional modifications and improvements of the present invention may also be apparent to those of ordinary skill in the art. Thus, the particular combination of parts described and illustrated herein is intended to represent only a certain embodiment of the present invention, and is not intended to serve as a limitation of alternative devices within the spirit and scope of the invention.
|
An infiltration cannula and method of using the infiltration cannula during an infiltration procedure are disclosed herein. The infiltration cannula includes: a tubular needle and a hub. The tubular needle has a proximal end and a distal end. The tubular needle also has a plurality of apertures disposed in a pattern about the distal end. The apertures are configured to infiltrate fluid into the subcutaneous tissue of a patient. The hub is configured to be held by a person performing the infiltration procedure. The hub has a first end and an opposing second end. The first end is attached to the proximal end of the tubular needle and the second end includes a connector configured to connect to an input source for receiving the fluid to be infiltrated into the subcutaneous tissue of the patient. The fluid flows from the connector, through the hub and into the tubular needle.
| 0
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to gelled diethylene glycol to be used as a heat source or fuel. More particularly, this invention relates to a composition of matter consisting essentially of diethylene glycol and a fumed silica product.
2. Description of the Prior Art
Portable heat sources have been used for many years including, campers and military personnel. To avoid the bulk and impracticality of liquid sources inherent in camp stoves, a number of devices have been invented to provide a source of fuel in a gelled or colloidal form. One such device is a gelled alcohol marketed as STERNO. Because of its volatile characteristics inherent in alcoholic compositions, this device suffers from several limitations and disadvantages. First, when ignited, the heat degenerates the gel to a liquid form, which may spread a fire rapidly if spilled. Further, due to its volatile nature, it emits fumes and a considerable odor when burned which are harmful to the health of those in close proximity.
Another gelled heat source is disclosed and defined in U.S. Pat. No. 4,302,208. This invention relates to a fuel for fuel air explosive devices for military uses and its composition consists of a polar fuel, silicon dioxide and a mixture of two alcohols. One of the alcohol compositions contains an ether linkage, with volatile characteristics with such limitations as described above.
Another fuel source is disclosed and defined in U.S. Pat. No. 4,756,719. This invention relates to a composition consisting of a combustible polymer, an organic solvent and a course powder of fiber material. The disadvantage and limitations inherent in organic based fuels are its tendencies to evaporate quickly and emit fumes and odors which may be poisonous or noxious.
It is therefore, an object of the present invention to provide a small efficient gelled fuel heat source primarily for field use in heating food and which is neither poisonous or noxious and which does not evaporate quickly. It is a further object of the present invention to provide a fuel source which maintains its high degree of viscosity over a long shelf life and during turbulent handling and shipping conditions.
The present invention represents an improved and novel composition. It is characterized by a number of advantages which increases its utility over prior art heat sources. These and other objects and advantages of the present invention will become evident from the following disclosure to those skilled in the art to which this invention pertains.
SUMMARY OF THE INVENTION
The preferred embodiment of the present invention relates to a gelled fuel heat source consisting of diethylene glycol and a fumed silicon product. Use of diethylene glycol as a fuel source has many advantages over the prior art such as alcohol and organic based fuel sources. Diethylene glycol burns clearly without fumes or odor. When mixed with a fumed silica product as a gelling agent, a gel forms with a high degree of viscosity capable of being packaged in an envelope, can, or tube. Addition of the fumed silica product produces good wicking characteristics with a high flash point. Further, the diethylene glycol contributes a high caloric value to the gel which requires only a small portion for each use. The composition may be used directly a field use includes fuel for heating food or as a starter for igniting firewood.
This is a mechanical means for gelling, however, several chemical means have also been found to produce desirable results.
One chemical means for gelling or solidifying the diethylene glycol was to react the diethylene glycol with stearic acid. When 5 percent to 40 percent by weight of stearic acid is heated with the diethylene glycol until dissolved, upon cooling, a wax-like candle is formed. Because the material is semi-solid, a conventional wick can be used to ignite the material. If I to 5% of fumed silica is added to the total mixture, sufficient wicking is provided by the silica alone. One added feature of this mixture, if reacted long enough, is that the material can be used as a soap in addition to being a fuel source.
A second means of chemically gelling or solidifying diethylene glycol is to react it with 10 percent to 40 percent by weight of polyethylene glycol. This mixture must also be heated to dissolve the polyethylene glycol. If 1 percent to 5 percent by weight of fumed silica is added for wicking, an easily ignitable mixture can be prepared which burns with a pale blue flame, that is very difficult to extinguish.
Another means of chemically gelling diethylene glycol is to react it with 10 percent to 40 percent by weight of polyvinyl alcohol. When heated to 200° F to 300° F and cooled to room temperature, the mixture forms a rubbery semi-solid material. While burning it melts like a wax candle.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The composition of this invention is made up by mixing diethylene glycol and a fumed silica product. This very fine silica product increases the viscosity of the diethylene glycol from a liquid to a gelled form. Such silica products are commercially available under the trade names CAB-0-SIL and AEROSIL. Even though the vapor pressure is very low for diethylene glycol, the fumed silica acts like a wick for the mixture and can be easily ignited with a match. The product when heated does not melt or soften but remains in its semi-solid condition. It burns clean with no smoke or odor and leaves only the silica residue.
It has been discovered that while this composition has desirable viscous characteristics upon formulation, it has a tendency to become less viscous with severe agitation. A trace quantity of a caustic compound when added to the aforementioned composition will stabilize the viscous characteristics of the gelled mixture. Examples of caustic compounds suitable for use include sodium hydroxide, potassium hydroxide, and calcium oxide. Tests have disclosed that traces of a caustic compound in the range of about 0.05 to 0.5 percent by weight is sufficient to retain the gel's viscous characteristics.
The preferred weight percentages for the composition consists of 5 to 25 percent of fumed silica, 75 to 95 percent diethylene glycol and 0.05 to 0.5 percent of a caustic compound.
In an alternative composition, fly ash may be used to replace some of the more expensive fumed silica in a range of I0 to 40 percent by weight. This substitution may result in more than a 50 percent formulation cost savings using a mix by weight of fly ash of 40 percent and a 2 percent mix by weight of fumed silica. Additionally, the fly ash provides the caustic characteristics which retains the viscous quality of the gelled composition.
The composition may be packaged with military field rations where a simple envelop would be used to heat water for soup and coffee. The tubes will also find ready application among the military, scouters, and campers. The canned material can be used.
The compositions of the present invention when prepared according to the ranges of weight percentages set forth above, may be packaged in a variety of manners. For single use applications, the gel may be packaged in envelopes of aluminum foil, plastics, or plastic lined paper. For multiple use applications, the gel may be packaged in plastic or foil tubes (like toothpaste), and the desired amount can be squeezed out and ignited. Additionally, the gel may also be packaged in metal cans of various shapes.
|
A stable gelled material used as a fuel which consists of a composition of diethylene glycol mixed with a gelling agent of fumed silica. Polyethylene glycol may also be added to improve its burning characteristics.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional filing from commonly owned, application Ser. No. 13/402,983, filed 23 Feb. 2012, now U.S. Pat. No. 8,999,909, the disclosure of which is hereby incorporated herein by reference.
FIELD OF THE INVENTION
The present invention pertains to azeotropic or azeotrope-like compositions of 1,1,1,3,3-pentachloropropane (HCC-240fa or 240fa) and hydrogen fluoride (HF).
BACKGROUND OF THE INVENTION
Chlorofluorocarbon (CFC) based chemicals have been widely use in industry in a variety of different applications including as refrigerants, aerosol propellants, blowing agents and solvents, among others. However, certain CFCs are suspected of depleting the Earth's ozone layer. Accordingly, more environmentally friendly substitutes have been introduced as replacements for CFCs. For example, 1,1,1,3,3-pentafluoropropane (HFC-245fa) is recognized as having favorable physical properties for certain industrial applications, such as foam blowing agents and solvents, and therefore is consider to be a good substitute for the CFCs previously used for these applications. Unfortunately, the use of certain hydrofluorocarbons, including HFC-245fa, in industrial applications is now believed to contribute to the global warming. Accordingly, more environmentally friendly substitutes for hydrofluorocarbons are now being sought.
The compound 1-chloro-3,3,3-trifluoropropene, also known as HCFO-1233zd or simply 1233zd, is a candidate for replacing HFC-245fa in some applications, including uses as blowing agents and solvents. 1233zd has a Z-isomer and an E-isomer. Due to differences in the physical properties between these two isomers, pure 1233zd (E), pure 1233zd (Z), or certain mixtures of the two isomers may be suitable for particular applications as refrigerants, propellants, blowing agents, solvents, or for other uses.
The compound 1,1,1,2,3-pentachloropropane (240fa) is a reactant useful in the production of both 245fa and 1233zd. Processes for making these compounds are well known in the art. See for example, U.S. Pat. Nos. 5,763,706 and 6,844,475. See also, U.S. Patent Publication No. 2011-0201853, which provides an integrated process and methods of producing 1233zd (E).
It has now been found that an important intermediate in the production of both 245fa and 1233zd, is an azeotrope or azeotrope-like mixture of 1,1,1,3,3-pentachloro-propane (240fa) and hydrogen fluoride (HF). This intermediate, once formed, may thereafter be separated into its component parts, for example, by extraction or distillation techniques. HCC-240fa has a boiling point of about 178.5° C. and HF has a boiling point of about 20° C. at standard atmospheric pressure. These azeotropic or azeotrope-like compositions find use not only as reactor feeds in the production of 245fa and 1233zd, but they are additionally useful as solvent compositions useful for removing surface oxidation from metals.
SUMMARY OF THE INVENTION
The present invention is directed to azeotropic or azeotrope-like mixtures of 1,1,1,3,3-pentachloropropane (240fa) and hydrogen fluoride. Such compositions are useful as an intermediate in the production of HFC-245fa and HCFO-1233zd.
In certain embodiments of this mixture, the composition comprises effective amounts of 1,1,1,3,3-pentachloro-propane (240fa) and hydrogen fluoride (HF).
In certain embodiments of this mixture, the azeotropic or azeotrope-like composition of the invention consists essentially of from about 90 to about 97 weight percent hydrogen fluoride and from about 10 to about 3 weight percent 1,1,1,3,3-pentachloropropane (240fa), which composition has a boiling point of about 24° C. to about 60° C. at pressure of about 17.8 psia to pressure of about 55.4 psia.
In certain embodiments of this mixture, the composition consists of hydrogen fluoride and 1,1,1,3,3-pentachloropropane (240fa).
In certain embodiments of this mixture, the composition comprises from about 99 to about 1 weight percent HF.
In certain embodiments of this mixture, the composition comprises from about 40 weight percent to about 97 weight percent HF.
In certain embodiments of this mixture, the composition comprises from about 60 to about 3 weight percent 240fa.
In certain embodiments of this mixture, the composition comprises from about 90 weight percent to about 95 weight percent 240fa.
In certain embodiments of this mixture, the composition comprises from about 10 weight percent to about 5 weight percent 240fa.
In certain embodiments of this mixture, the composition has a boiling point of about from 24° C. to about 60° C. at a pressure from about 17.8 psia to about 55.4 psia.
In certain embodiments of this mixture, the invention is directed to an azeotropic or azeotrope-like composition having about 92±2 weight percent HF and about 8±2 weight percent 240fa has a boiling point of about 24° C. at 17.8 psia.
Another aspect of the present invention is directed to a method of forming an azeotropic or azeotrope-like composition which comprises blending hydrogen fluoride and 1,1,1,3,3-pentachloropropane (240fa), which composition has a boiling point of about 24° C. to about 60° C. at pressure of about 17.8 psia to pressure of about 55.4 psia.
In certain embodiments of this method, the composition consists essentially of from about 90 to about 97 weight percent hydrogen fluoride and from about 10 to about 3 weight percent 1,1,1,3,3-pentachloropropane (240fa).
In certain embodiments of this method, the composition consists of hydrogen fluoride and 1,1,1,3,3-pentachloropropane (240fa).
In certain embodiments of this method, the composition consists essentially of about 92±2 weight percent HF and about 8±2 weight percent 240fa and has a boiling point of about 24° C. at 17.8 psia.
Another aspect of the present invention is directed to a method of forming a heterogeneous azeotropic or azeotrope-like composition which comprises blending from about 0.2 to about 97 weight percent hydrogen fluoride and from about 99.8 to about 3 weight percent 1,1,1,3,3-pentachloropropane (240fa), which composition has a boiling point of about from 24° C. to about 60° C. at pressure of about from 17.8 psia to about 55.4 psia.
In certain embodiments of this method, the composition comprises from about 99 to about 1 weight percent HF.
In certain embodiments of this method, the composition comprises from about 40 weight percent to about 97 weight percent HF.
In certain embodiments of this method, the composition comprises from about from about 90 to about 97 weight percent HF.
In certain embodiments of this method, the composition comprises from about 60 to about 3 weight percent 240fa.
In certain embodiments of this method, the composition comprises from about 90 weight percent to about 95 weight percent 240fa.
In certain embodiments of this method, the composition comprises from about 10 weight percent to about 3 weight percent 240fa.
In certain embodiments of this method, the composition has a boiling point of about from 24° C. to about 60° C. at a pressure from about 17.8 psia to about 55.4 psia.
Another aspect of the present invention is directed to a method of separating 240fa from the azeotropic like mixture of 240fa and HF comprising the step of extracting the HF from the mixture.
In certain embodiments of this method, the extraction of HF is accomplished using water or other aqueous solution.
In certain embodiments of this method, the extraction of HF is accomplished using sulfuric acid.
In certain embodiments of this method, the extraction of HF is accomplished by distillation.
In certain embodiments of this method, the distillation comprises extractive distillation.
In certain embodiments of this method, the distillation comprises pressure swing distillation.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a plot of the vapor pressures of the mixtures formed in Example 1 and Example 2 as measured at 30° C. and 60° C.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a heterogeneous azeotropic composition consisting essentially of 1,1,1,1,3-pentachloropropane (240fa) and hydrogen fluoride (HF).
The invention further provides an azeotropic or azeotrope-like composition which consists essentially of from about 90 to about 97 weight percent hydrogen fluoride and from about 10 to about 3 weight percent 1,1,1,3,3-pentachloropropane (240fa), which composition has a boiling point of about 24° C. to about 60° C. at pressure of about 17.8 psia to pressure of about 55.4 psia.
The invention also provides a method of forming a heterogeneous azeotropic or azeotrope-like composition which consists essentially of blending from about 0.2 to about 97 weight percent hydrogen fluoride and from about 99.8 to about 3 weight percent 1,1,1,3,3-pentachloropropane (240fa), which composition has a boiling point of about—from 24° C. to about 60° C. at pressure of about from 17.8 psia to about 55.4 psia.
When 1,1,1,3,3-pentachloropropane (240fa) and HF were added to a vessel, it was observed that 240fa forms an azeotropic or azeotrope-like mixture with HF. The unreacted 240fa/HF intermediate was found in the vapor space of the vessel.
The thermodynamic state of a fluid is defined by its pressure, temperature, liquid composition and vapor composition. For a true azeotropic composition, the liquid composition and vapor phase are essentially equal at a given temperature and pressure. In practical terms this means that the components cannot be separated during a phase change.
For the purpose of this invention, an azeotrope is a liquid mixture that exhibits a maximum or minimum boiling point relative to the boiling points of surrounding mixture compositions. An azeotrope or an azeotrope-like composition is an admixture of two or more different components which, when in liquid form under given pressure, will boil at a substantially constant temperature, which temperature may be higher or lower than the boiling temperatures of the components and which will provide a vapor composition essentially identical to the liquid composition undergoing boiling.
For the purpose of this invention, azeotropic compositions are defined to include azeotrope-like compositions, which means, a composition that behaves like an azeotrope, i.e., has constant-boiling characteristics or a tendency not to fractionate upon boiling or evaporation. Thus, the composition of the vapor formed during boiling or evaporation is the same as or substantially the same as the original liquid composition. Hence, during boiling or evaporation, the liquid composition, if it changes at all, changes only to a minimal or negligible extent. This is in contrast with non-azeotrope-like compositions in which during boiling or evaporation, the liquid composition changes to a substantial degree.
Accordingly, the essential features of an azeotrope or an azeotrope-like composition are that at a given pressure, the boiling point of the liquid composition is fixed and that the composition of the vapor above the boiling composition is essentially that of the boiling liquid composition, i.e., essentially no fractionation of the components of the liquid composition takes place. Both the boiling point and the weight percentages of each component of the azeotropic composition may change when the azeotrope or azeotrope-like liquid composition is subjected to boiling at different pressures. Thus, an azeotrope or an azeotrope-like composition may be defined in terms of the relationship that exists between its components or in terms of the compositional ranges of the components or in terms of exact weight percentages of each component of the composition characterized by a fixed boiling point at a specified pressure.
The present invention provides a composition which comprises effective amounts of hydrogen fluoride and 240fa to form an azeotropic or azeotrope-like composition. By effective amount is meant an amount of each component which, when combined with the other component, results in the formation of an azeotrope or azeotrope-like mixture. The inventive compositions preferably are binary azeotropes which consist essentially of combinations of only hydrogen fluoride with 240fa.
In the preferred embodiment, the inventive composition contains from about 99 to about 1 weight percent HF, preferably from about 1 weight percent to about 99 weight percent and most preferably from about 40 weight percent to about 97 weight percent. In the preferred embodiment, the inventive composition contains from about 60 to about 3 weight percent 240fa preferably from about 90 weight percent to about 95 weight percent and most preferably from about 10 weight percent to about 5 weight percent. The composition of the present invention has a boiling point of about from 24° C. to about 60° C. at a pressure from about 17.8 psia to about 55.4 psia. An azeotropic or azeotrope-like composition having about 92±2 weight percent HF and about 8±2 weight percent 240fa has been found to boil at about 24° C. and 17.8 psia.
EXAMPLES
The following non-limiting examples serve to illustrate the invention.
Example 1
9 g of 1,1,1,3,3-pentachloropropane (240fa) were dissolved in 14.7 g of HF to form a heterogeneous azeotrope mixture. This experiment was done at 24° C., and at 17.8 psia.
Example 2
Binary compositions containing solely 1,1,1,3,3-pentachloropropane (240fa) and HF are blended to form a heterogeneous azeotrope mixtures at different compositions. The vapor pressures of the mixtures are measured at about 29.9° C., 30° C. and 60° C. and the following results are noticed.
Tables 1 and 2 show the vapor pressure measurement of 240fa and HF as a function of composition of weight percent HF at constant temperatures of about 29.9° C., 30° C. and 60° C.
TABLE 1
P-T-X of 240fa/HF at T = 30° C. and 60°
P (Psia)
Wt. % HF
T = 30° C.
T = 60° C.
0
0.4
0.69
9.7
21.4
53.9
17.4
21.6
54.6
91.3
21.3
55.4
100
21.1
52.9
As shown in Table 1, variation of the amount of HF in the composition shows no significant (+/−0.3 psia or less) change in pressure at 30° C., and similarly no significant change in pressure (+/−0.8 psia) at 60° C., supporting the azeotrope-like nature of the composition over this range of HF in the composition.
TABLE 2
P-T-X of 240fa/HF at T = 29.9 c
Wt. % HF
P (psia)
0
0.4
10.7
20.6
27.1
21.2
40.4
21.3
47.8
21.6
51.6
21.5
65.4
21.6
70.8
21.3
81.0
21.2
100
21.1
As shown in Table 2, variation of the amount of HF in the composition shows no significant (+/−1 psia or less) change in pressure at 29.9° C., supporting the azeotrope-like nature of the composition over this range of HF in the composition.
These data show that the mixture is an azeotrope or azeotrope-like since the vapor pressures of mixtures of 240fa and HF are higher, at all indicated blend proportions, than 240fa and HF alone, i.e., as indicated in the first and last rows when HF is 0.0 wt % and 240fa is at 100.0 wt % as well as when 240fa is at 0.0 wt % and HF is at 100.0 wt. %. The data from Table 1 are shown in graphic form in FIG. 1 .
Example 3
The azeotropic composition of the 240fa/HF mixture is also verified by Vapor-Liquid-Liquid Equilibrium (VLLE) experiment.
62.6 g of 1,1,1,3,3-pentachloropropane (240fa) are dissolved in 31.6 g of HF to form a heterogeneous mixture (visual observation) at 24° C. The vapor compositions of the mixture were sampled at room temperature of 24° C. The result shows that the azeotropic composition is about 92±2 wt % HF at 24° C.
As used herein, the singular forms “a”, “an” and “the” include plural unless the context clearly dictates otherwise. Moreover, when an amount, concentration, or other value or parameter is given as either a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope of the invention be limited to the specific values recited when defining a range.
It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.
|
Provided are methods for forming azeotropic or azeotrope-like mixtures of 1,1,1,3,3-pentachloro-propane (240fa) and hydrogen fluoride. Such compositions are useful as an intermediate in the production of HFC-245fa and HCFO-1233zd.
| 2
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a frequency division circuit using a flip-flop circuit combining therein bipolar transistors and MOS transistors and a buffer circuit.
[0003] 2. Description of the Related Art
[0004] FIG. 2 shows a conventional frequency division circuit comprising a flip-flop circuit 21 using bipolar transistors and a buffer circuit 22 . The reference numerals 211 - 228 stand for bipolar transistors, 231 —a power source voltage terminal, 201 - 204 —load resistors, 205 - 208 —resistors determining the current of a constant current source. Pairs of transistor 211 and transistor 214 , transistor 212 and transistor 213 , transistor 215 and transistor 218 , transistor 216 and transistor 217 , transistor 221 and transistor 222 , and transistor 223 and transistor 224 form respective differential pairs. A data signal D is inputted to the base of the bipolar transistor 211 , and a data signal ND is inputted to the base of the bipolar transistor 214 . As for the clock signals Ck and NCk, the clock signal Ck is inputted to the bipolar transistors 222 , 223 , and the clock signal NCk is inputted to the bipolar transistor 221 , 224 .
[0005] The operation principle will be described below. When a HIGH signal is inputted as a clock signal to a clock input terminal 234 (clock signal LOW is inputted to the clock input terminal 235 ), the bipolar transistors 221 , 224 are switched ON and the differential pair formed by the bipolar transistors 211 , 214 and the differential pair formed by the bipolar transistors 216 , 217 become operative. Owing to the operation of the differential pair formed by the bipolar transistors 211 , 214 , the output of the load resistors 201 , 202 is outputted in response to signals of data signals D, ND inputted to the data input terminals 232 , 233 . The output data of the load resistors 201 , 202 are inputted to the differential pair formed by the bipolar transistors 215 , 218 . The operation of the bipolar transistors 215 , 218 is OFF, the operation of the bipolar transistors 216 , 217 is ON, and the output signal of the load resistors 203 , 204 holds the data preceding the input of the clock signals to the clock input terminals 234 , 235 .
[0006] When a HIGH signal is inputted as a clock signal to a clock signal input terminal 235 (clock signal LOW is inputted to the clock input terminal 234 ), the bipolar transistors 222 , 223 are switched ON and the differential pair formed by the bipolar transistors 212 , 213 and the differential pair formed by the bipolar transistors 215 , 218 become operative. Owing to the operation of the differential pair formed by the bipolar transistors 212 , 213 , the output of the load resistors 201 , 202 holds the previous output state. The output signals of the load resistors 201 , 202 are inputted to the differential pair formed by the bipolar transistors 215 , 218 . The operation of the bipolar transistors 215 , 218 is ON, the operation of the bipolar transistors 216 , 217 is OFF, and the output signal of the load resistors 203 , 204 is outputted in response to the clock signals inputted from the clock input terminals 234 , 235 and data signals outputted from the load resistors 201 , 202 .
[0007] Furthermore, when the output terminal of the frequency division circuit does not shift the level of the output signal voltage, output terminals 241 , 242 are used. When the output voltage of the flip-flop circuit 21 is level shifted and outputted, the output voltage is shifted and outputted by using the buffer circuit 22 . This buffer circuit 22 comprises bipolar transistors 219 , 220 , 227 , 228 with a short delay time.
[0008] In the case of a bipolar transistor three-stage structure shown in FIG. 2 , the base-emitter voltage Vbe of each transistor is 0.7 V, the base-collector voltage Vbc is 0.1 V, and when the voltage applied to the load resistor of the flip-flop circuit is taken as 0.3 V, the minimum necessary power source voltage becomes 0.7×3+0.1×3+0.3=2.7 V. As a result, the flip-flop circuit 21 with the bipolar transistor three-stage structure is inadequate for low-voltage operation.
[0009] FIG. 3 shows a conventional frequency division circuit comprising a flip-flop circuit 31 using MOS transistors and a buffer circuit 32 . The reference numerals 311 - 328 stand for MOS transistors and the reference numerals 301 - 304 stand for load resistors. Pairs of MOS transistor 311 and MOS transistor 314 , MOS transistor 312 and MOS transistor 313 , MOS transistor 315 and MOS transistor 318 , MOS transistor 316 and MOS transistor 317 , MOS transistor 321 and MOS transistor 322 , and MOS transistor 323 and MOS transistor 324 form respective differential pairs. A data signal D is inputted to the base of the MOS transistor 311 , and a data signal ND is inputted to the base of the MOS transistor 314 . As for the clock signals Ck and NCk, the clock signal Ck is inputted to the MOS transistors 322 , 323 , and the clock signal NCk is inputted to the bipolar transistor 321 , 324 .
[0010] The operation principle will be described below. When a HIGH signal is inputted as a clock signal to a clock input terminal 334 (clock signal LOW is inputted to the clock input terminal 335 ), the MOS transistors 321 , 324 are switched ON and the differential pair formed by the MOS transistors 311 , 314 and the differential pair formed by the MOS transistors 316 , 317 become operative. Owing to the operation of the differential pair formed by the MOS transistors 311 , 314 , the output of the load resistors 301 , 302 is outputted in response to signals of data signals D, ND inputted to the data input terminals 332 , 333 . The output data of the load resistors 301 , 302 are inputted to the differential pair formed by the MOS transistors 315 , 318 . The operation of the MOS transistors 315 , 318 is OFF, the operation of the MOS transistors 316 , 317 is ON, and the output signal of the load resistors 303 , 304 holds the data preceding the input of the clock signals to the clock input terminals 334 , 335 .
[0011] When a HIGH signal is inputted as a clock signal to a clock signal input terminal 335 (clock signal LOW is inputted to the clock input terminal 334 ), the MOS transistors 322 , 323 are switched ON and the differential pair formed by the MOS transistors 312 , 313 and the differential pair formed by the MOS transistors 315 , 318 become operative. Owing to the operation of the differential pair formed by the MOS transistors 312 , 313 , the output of the load resistors 301 , 302 holds the previous output state. The output signals of the load resistors 301 , 302 are inputted to the differential pair formed by the MOS transistors 315 , 318 . The operation of the MOS transistors 315 , 318 is ON, the operation of the MOS transistors 316 , 317 is OFF, and the output signal of the load resistors 303 , 304 is outputted in response to the clock signals inputted from the clock input terminals 334 , 335 and data signals outputted from the load resistors 301 , 302 .
[0012] Furthermore, when the output terminal of the frequency division circuit does not shift the level of the output signal voltage, output terminals 341 , 342 are used. When the output voltage of the flip-flop circuit 31 is level shifted and outputted, the output voltage is shifted and outputted by using the buffer circuit 32 . This buffer circuit comprises MOS transistors 319 , 320 , 327 , 328 .
[0013] In the case of a MOS transistor three-stage structure shown in FIG. 3 , the minimum required source voltage becomes lower than that of the configuration using bipolar transistors. In particular, the minimum required source voltage of a MOS with a low threshold voltage decreases and the flip-flop circuit 31 is suitable for low-voltage operation. However, because MOS transistors have a frequency characteristic worse that that of the bipolar transistors, the operation frequency decreases.
[0014] Further, because MOS transistors are provided in the buffer circuit 32 , the delay time of input and output signals of the buffer circuit 32 becomes much longer than that of the buffer circuit 22 comprising bipolar transistors.
[0015] A flip-flop circuit of another embodiment disclosed in Japanese Patent Application Laid-open No. H9-69759A (shown in FIG. 4 ) was suggested as a frequency division circuit comprising a flip-flop circuit using bipolar transistors and capable of operating at a low voltage.
[0016] The conventional circuit shown in FIG. 4 constitutes a latch circuit comprising a first transistor differential pair Q 1 -Q 3 , a second transistor differential pair Q 4 -Q 6 , first and second load resistors R 11 , R 12 , and constant current sources Q 13 , R 19 , Q 14 , R 20 . Similarly, another latch circuits is composed of a third transistor differential pair Q 7 -Q 9 , fourth transistor differential pair Q 10 -Q 12 , third and fourth load resistors R 13 , R 14 , and constant current sources Q 15 , R 22 , Q 16 , and R 21 . This conventional flip-flop circuit reads the data of data input D, D bar when a clock input T is HIGH and outputs the read-out data to Q and Q bar when the clock input T is LOW.
[0017] In this conventional circuits, the transistors Q 1 , Q 4 , Q 7 , and Q 10 into which the clock signals are inputted and the emitters of transistors Q 2 , Q 3 , Q 5 , Q 6 , Q 8 , Q 11 , and Q 12 into which the data input signals are inputted are connected via emitter return resistors R 15 -R 18 to conduct switching. As a result, the number of stacking stages of transistors Q 1 -Q 12 and Q 13 -Q 16 connected between the power source and GND is reduced by one. Reducing by one the number of transistor stages between the power source and GND enables the low-voltage operation.
[0018] In the conventional flip-flop circuit 21 using bipolar transistors shown in FIG. 2 , the minimum necessary power source voltage is high, making the circuit inadequate for low-voltage operation. Furthermore, the conventional flip-flop circuit 31 using MOS transistors shown in FIG. 3 is adequate for low-voltage operation, but the operation frequency in the frequency characteristic decreases with respect to that of the flip-flop circuit using bipolar transistors. Furthermore, in the conventional example shown in FIG. 4 , in order to produce a low-voltage flip-flop circuit comprising only bipolar transistors, the clock signal input uses the output of the differential circuit and the flip-flop circuit itself has a folded-type structure. Therefore, the electric current apparently increases over that of a three-stage longitudinally stacked structure of transistors.
SUMMARY OF THE INVENTION
[0019] The present invention was achieved to resolve the above-described problems and it is an object thereof to obtain a flip-flop circuit suitable for low-voltage operation and having a high operation frequency and a frequency division circuit using such flip-flop circuit.
[0020] In order to attain the above-described object the flip-flop circuit in accordance with the present invention has a three-stage configuration of transistors connected between the power source voltage and GND, this configuration being identical to the conventional configuration. In this configuration, using bipolar transistors for the upper-stage transistors of the three-stage structure enables the circuit to operate in a frequency range up to a high frequency, and using MOS transistors with a low threshold for the transistors of the medium and lower stages of the three-stage structure of the flip-flop circuit ensures low-voltage operation.
[0021] The flip-flop circuit of the first invention comprises a MOS transistor ( 121 ) to which a clock input NCk shown in FIG. 1 is input, bipolar transistors ( 111 , 114 ) having emitters thereof commonly connected to the MOS transistor, executing a differential operation after being input with data input signals (D, ND), and outputting signals of load resistors ( 101 , 102 ), a MOS transistor ( 122 ) to which a clock input (Ck) is input, bipolar transistors ( 112 , 113 ) having emitters thereof commonly connected to this MOS transistor, executing a differential operation after being input with output signals of load resistors ( 101 , 102 ), and holding the signals of load resistors ( 101 , 102 ), a MOS transistor ( 123 ) to which a clock input (Ck) is input, bipolar transistors ( 115 , 118 ) having emitters thereof commonly connected to this MOS transistor, executing a differential operation after being input with output signals of load resistors ( 101 , 102 ), and outputting signals of load resistors ( 103 , 104 ), a MOS transistor ( 124 ) to which a clock input (NCk) is input, and bipolar transistors ( 116 , 117 ) having emitters thereof commonly connected to this MOS transistor, executing a differential operation after being input with output signals of load resistors ( 103 , 104 ), and holding the signals of load resistors ( 103 , 104 ).
[0022] In the flip-flop circuit of the second invention, the layout of transistors of each pair in four sets of bipolar transistors ( 111 , 112 ), ( 113 , 114 ), ( 115 , 116 ), ( 117 , 118 ) forming differential pairs is such that they have common collector electrodes.
[0023] A MOS transistor with a low threshold is comprised as the MOS transistor comprised in the flip-flop circuit of the third invention.
[0024] The frequency division circuit of the fourth invention comprises the flip-flop circuit of the first to third inventions and a buffer circuit comprising bipolar transistors ( 119 , 120 ) and has MOS transistors ( 127 , 128 ) in the current sources.
[0025] The frequency division circuit comprising the flip-flop circuit in accordance with the present invention and the buffer circuit enables low-voltage and high-frequency operation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a circuit diagram of a flip-flop circuit and a frequency division circuit of one embodiment of the present invention;
[0027] FIG. 2 is a circuit diagram of a conventional flip-flop circuit using bipolar transistors;
[0028] FIG. 3 is a circuit diagram of the conventional flip-flop circuit using MOS transistors; and
[0029] FIG. 4 is a circuit diagram of another conventional flip-flop circuit using bipolar transistors.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] The preferred embodiments of the present invention will be described below with reference to FIG. 1 .
[0031] FIG. 1 is a structural drawing illustrating a frequency division circuit of the embodiment of the present invention, this circuit comprising a flip-flop circuit 11 and a buffer circuit 12 . Referring to FIG. 1 , the reference numerals 101 - 104 stand for load resistors, 111 - 120 —bipolar transistors, 121 - 128 —MOS transistors. The MOS transistors 121 - 128 comprise low-threshold MOS transistors.
[0032] The flip-flop circuit 11 is produced by connecting the load resistors 101 - 104 , bipolar transistors 111 - 118 , and MOS transistors 121 - 126 as shown in FIG. 1 . The buffer circuit 12 is provided by connecting the bipolar transistors 119 , 120 and MOS transistors 127 , 128 as shown in FIG. 1 .
[0033] The bipolar transistor 111 and bipolar transistor 114 , bipolar transistor 112 and bipolar transistor 113 , bipolar transistor 115 and bipolar transistor 118 , bipolar transistor 116 and bipolar transistor 117 , MOS transistor 121 and MOS transistor 122 , and MOS transistor 123 and MOS transistor 124 represent differential pairs.
[0034] The bipolar transistor 111 and bipolar transistor 112 , bipolar transistor 113 and bipolar transistor 114 , bipolar transistor 115 and bipolar transistor 116 , and bipolar transistor 117 and bipolar transistor 118 have common collectors, and load resistors 101 - 104 are connected between a power source voltage terminal 131 and respective common collectors.
[0035] Further, a data input terminal 132 is connected to the base of the bipolar transistor 111 , and the data input terminal 133 is connected to the base of the bipolar transistor 114 . Furthermore, the emitter of the bipolar transistor 111 and the emitter of the bipolar transistor 114 are connected, and the emitter of the bipolar transistor 112 and the emitter of the bipolar transistor 113 are connected. The base of the bipolar transistor 112 is connected to the collector of the bipolar transistor 113 ( 114 ) and the base of the bipolar transistor 118 . The base of the bipolar transistor 113 is connected to the collector of the bipolar transistor 111 ( 112 ) and the base of the bipolar transistor 115 .
[0036] Further, the emitter of the bipolar transistor 115 and the emitter of the bipolar transistor 118 are connected, and the emitter of the bipolar transistor 116 and the emitter of the bipolar transistor 117 are connected. Furthermore, the base of the bipolar transistor 116 is connected to the base of the collector of the bipolar transistor 117 ( 118 ), and the base of the bipolar transistor 117 is connected to the base of the collector of the bipolar transistor 115 ( 116 ). Further, the collector of the bipolar transistor 115 ( 116 ) is connected to an output terminal 141 , and the collector of the bipolar transistor 117 ( 118 ) is connected to the output terminal 142 .
[0037] The drain of the MOS transistor 121 is connected to the emitter of the bipolar transistor 111 ( 114 ), the gate of the MOS transistor 121 is connected to the clock input terminal 134 , the drain of the MOS transistor 122 is connected to the emitter of the bipolar transistor 112 ( 113 ), the gate of the MOS transistor 122 is connected to the clock input terminal 135 , and the MOS transistor 121 and MOS transistor 122 have common sources.
[0038] Furthermore, the drain of the MOS transistor is connected to the emitter of the bipolar transistor 115 ( 118 ), the gate of the MOS transistor 123 is connected to the clock input terminal 135 , the drain of the MOS transistor 124 is connected to the emitter of the bipolar transistor 116 ( 117 ), the gate of the MOS transistor 124 is connected to the clock input terminal 134 , and the MOS transistor 123 and MOS transistor 124 have common sources.
[0039] Gates of the MOS transistor 125 and MOS transistor 126 are connected to a bias terminal 136 of a low-current source, the drain of the MOS transistor 125 is connected to the source of the MOS transistor 121 ( 122 ), the drain of MOS transistor 126 is connected to the source of the MOS transistor 123 ( 124 ), and the sources of the MOS transistor 125 and MOS transistor 126 are connected to a GND terminal 137 .
[0040] In the buffer circuit 12 , the collectors of the bipolar transistor 119 and bipolar transistor 120 are connected to the power source voltage terminal 131 , the collector of the bipolar transistor 115 ( 116 ) is connected to the base of the bipolar transistor 120 , the collector of the bipolar transistor 117 ( 118 ) is connected to the base of the bipolar transistor 119 , the emitter of the bipolar transistor 119 is connected to the output terminal 138 and the drain of the MOS transistor 127 , and the emitter of the bipolar transistor 120 is connected to the output terminal 139 and the drain of the MOS transistor 128 .
[0041] Further, the bias terminal 136 of the low-current source is connected to the gate of the MOS transistor 127 , 128 , and the sources of MOS transistor 127 and MOS transistor 128 are connected to the GND 137 .
[0042] Thus, in the present embodiment the differential pair of the bipolar transistors 111 , 114 , the differential pair of the bipolar transistors 112 , 113 , the differential pair of bipolar transistors 115 , 118 , and the differential pair of bipolar transistors 116 , 117 comprise bipolar transistors of a differential model with a common collector electrode, thereby reducing the parasitic capacitance of the collector. The MOS transistors 125 - 128 are the current sources.
[0043] The operation principle is described below. When a HIGH signal is inputted as a clock signal to a clock signal input terminal 134 (clock signal LOW is inputted to the clock input terminal 135 ), the bipolar transistors 121 , 124 are switched ON and the differential pair formed by the bipolar transistors 111 , 114 and the differential pair formed by the bipolar transistors 116 , 117 become operative. Owing to the operation of the differential pair formed by the bipolar transistors 111 , 114 , the output of the load resistors 101 , 102 is outputted in response to signals of data signals D, ND inputted to the data input terminals 132 , 133 . The output data of the load resistors 101 , 102 are inputted to the differential pair formed by the bipolar transistors 115 , 118 . The operation of the bipolar transistors 115 , 118 is OFF, the operation of the bipolar transistors 116 , 117 is ON, and the output signal of the load resistors 103 , 104 holds the data preceding the input of the clock signals to the clock input terminals 134 , 135 .
[0044] When a HIGH signal is inputted as a clock signal to a clock signal input terminal 135 (clock signal LOW is inputted to the clock input terminal 134 ), the bipolar transistors 122 , 123 are switched ON and the differential pair formed by the bipolar transistors 112 , 113 and the differential pair formed by the bipolar transistors 115 , 118 become operative. Owing to the operation of the differential pair formed by the bipolar transistors 112 , 113 , the output of the load resistors 101 , 102 holds the previous output state. The output signals of the load resistors 101 , 102 are inputted to the differential pair formed by the bipolar transistors 115 , 118 . The operation of the bipolar transistors 115 , 118 is ON, the operation of the bipolar transistors 116 , 117 is OFF, and the output signal of the load resistors 103 , 104 is outputted in response to the clock signals inputted from the clock input terminals 134 , 135 and data signals outputted from the load resistors 101 , 102 .
[0045] Furthermore, when the output terminal of the frequency division circuit does not shift the level of the output signal voltage, output terminals 141 , 142 are used. When the output voltage of the flip-flop circuit 11 is level shifted and outputted, the output voltage is shifted and outputted by using the buffer circuit 12 . This buffer circuit 12 comprises bipolar transistors 119 , 120 with a short delay time. However, the transistors of the current source comprise the MOS transistors 127 , 128 for unification with the transistors of the current source of the flip-flop circuit.
[0046] The flip-flop circuit operating in the above-described manner comprises a differential pair of the bipolar transistors 111 , 114 , a differential pair of the bipolar transistors 112 , 113 , a differential pair of the bipolar transistors 115 , 118 , and a differential pair of the bipolar transistors 116 , 117 . Thus, it comprises bipolar transistors of a differential model with common collector electrode that have excellent high-frequency characteristics. As a result the parasitic capacitance of the collector is reduced. The reduction of the collector capacitance enables the operation with the output signal of the load resistance 101 - 104 having a higher frequency.
[0047] Furthermore, the MOS transistors 121 - 124 are provided as the inputs of the clock signals 134 , 135 , and MOS transistors 125 - 128 are provided as current sources. Thus, low-threshold MOS transistors are provided. As a result, the operation is possible at a minimum necessary power source voltage which is lower that that of the structure using only bipolar transistors, as in the conventional example shown in FIG. 2 .
[0048] Thus, employing bipolar transistors of a differential model and low-threshold MOS transistors and using a structure in which the transistors are stacked in three stages makes it possible to realize a frequency division circuit comprising the flip-flop circuit 11 capable of operating at a low power voltage and providing for a high frequency characteristic and a buffer circuit 12 .
[0049] As explained hereinabove, the present invention provides a frequency division circuit comprising a flip-flop circuit and suitable for low-voltage and high-frequency operation.
|
An object of the present invention is to obtain a frequency division circuit including a flip-flop circuit capable of low-voltage and high-frequency operation. The frequency division circuit has bipolar transistors and MOS transistors. Thus, the circuit includes transistors that are connected to the transistor to which the clock input is input, that execute the differential operation after being input with data input signals, and that output signals of resistors, and also transistors that are similarly connected to the transistor to which Ck is input and that hold signals of resistors, transistors that are connected to the transistor to which Ck is input and that output signals of resistors, and transistors that are connected to the transistor to which NCk is input and that hold signals of resistors.
| 7
|
FIELD OF THE INVENTION
The present invention relates to a method for operating an internal combustion engine, in particular of a motor vehicle, in which method fuel is injected into the cylinders of the internal combustion engine, the fuel quantity injected into the individual cylinders being adjusted and in which method a lambda value is detected in the exhaust pipe of the internal combustion engine. Moreover, the present invention relates to an internal combustion engine that is suitable for carrying out this method.
BACKGROUND INFORMATION
For pollutant minimization in catalytic aftertreatment of exhaust gases with the aid of a closed-loop, three-way catalytic converter, it is known in the art that the air-fuel mixture should have a specific mass ratio. This ratio is indicated by the so-called excess-air factor “lambda”, and can be detected by a lambda sensor located in the exhaust pipe.
In known methods, the values measured by the lambda sensor are fed to a control loop which controls the injection quantities of the individual cylinders as a function of the lambda value during operation of the internal combustion engine.
However, in the case of a single lambda sensor located in the exhaust pipe, this closed-loop control is based only on the lambda value that is averaged over the individual cylinders.
Mixture differences in the individual cylinders which arise in spite of equal injection quantities or equal setpoint values of a control unit for the injection quantities, due to component tolerances and aging effects, cannot be predetermined or taken into account with respect to the calculation of the cylinder-specific injection quantity.
Some methods provide for a temporal assignment of the exhaust gases flowing through the exhaust pipe, and the lambda values thereof, to the individual cylinders. In this manner, the injection quantity can, in principle, be controlled individually for each cylinder by a single lambda sensor, but the measuring accuracy is impaired by mixing effects and turbulences of immediately successive exhaust quantities of different cylinders in the exhaust pipe.
Design approaches in which each cylinder is assigned a lambda sensor are technically very complex.
It is therefore an object of the present invention to provide a method for cylinder-specific adjustment of the injection quantity in internal combustion engines with one lambda sensor located in the exhaust pipe.
SUMMARY
This objective is achieved by a method according to the present invention in which statistical design of experiments theory is utilized to determine the influence of the injection quantities metered to the individual cylinders on the excess-air factor, which is measured in the exhaust pipe and averaged over all cylinders.
In this context, the injection quantities selected by a control unit are gradually changed for each individual cylinder, following an orthogonal experimental plan. After each step of the experimental plan, the lambda value in the exhaust pipe resulting from the change in the injection quantity is measured, and, upon completion of the experimental plan, a correction value for the injection quantity is determined individually for each cylinder using these measured values.
These correction values are used individually for each cylinder to adjust the injection quantities for subsequent injection processes so that the optimum air-fuel mixture is substantially always achieved in each cylinder.
The important advantage of the method according to the present invention is that the optimum injection quantity can be determined for each cylinder of the internal combustion engine using a single lambda sensor.
This is achieved by mathematically modeling the lambda value. To this end, the influence of several independent variables on the value of lambda is determined using a polynomial formulation for the dependent variable lambda.
The independent variables correspond to the injection quantities that are individually metered to each cylinder, so that the mathematical model yields lambda as a function of the injection quantities of the individual cylinders, with coefficients of the polynomial weighting the influence of the injection quantities of the cylinders.
The coefficients can be determined, for example, from the values established within the framework of the orthogonal experimental plan. However, coefficients can also be estimated or established by plausibility considerations.
Depending on the degree of the polynomial selected for the formulation, it is also possible to determine interactions between injection quantities of several cylinders.
Using a setpoint selected for lambda, for example, lambda=1, and solving the resulting equation, a mathematical model for lambda obtained in this manner allows calculation of the injection quantities for each cylinder for which the specified setpoint is reached.
The injection quantities calculated using the mathematical model generally differ from injection quantities selected by the control unit. This difference is essentially due to different combustion conditions and tolerances in the valve control, that is, of the valves of the individual cylinders, and represents the correction value for injection quantity adjustment.
One advantage of the present invention is the possibility of using injectors with far larger tolerances.
In conventional injection systems, the requirements on the flow tolerance of injectors are very high, resulting in correspondingly high reject quantities during manufacturing.
The adjustment method according to the present invention allows proper adjustment of the injection quantities of the individual cylinders even in the case of markedly different flow characteristics of different injectors, making it possible to set lambda to the optimum value for exhaust-gas aftertreatment.
Thus, the method according to the present invention also reduces the manufacturing costs of injection systems and, at the same time, improves the emission performance by using more cost-effective injectors with larger tolerances, and eliminates the influences of these tolerances on the lambda value using the method according to the present invention.
Moreover, the adjustment method according to the present invention has the advantage of not having to be executed during the entire operating time of the internal combustion engine or of the control unit controlling the internal combustion engine. This results in savings in cycle time of the processor of the control unit, which saved cycle time can be used for other purposes.
An embodiment of the method according to the present invention provides to store the determined correction values in the control unit and to retrieve them the next time the vehicle is started. Thus, it is possible to carry out a new adjustment at regular intervals, such as when the vehicle is serviced, and to make the newly determined correction values available for the further operation of the vehicle.
It is also conceivable to determine the correction values periodically during vehicle operation, which allows the system to also respond to short-term changes in the characteristics of the injectors, such as contamination of a nozzle, and to adapt the injection quantities to the new situation individually for each cylinder.
It is also suitable to carry out an adjustment at the manufacturer's site immediately after the manufacture of the motor vehicle.
A further embodiment of the method according to the present invention incorporates the use of a broadband lambda sensor, which allows the lambda value to be determined in an interval from 0.7 <lambda <4 in continuous values.
A further embodiment of the method according to the present invention uses a so-called “voltage-jump sensor,” a lambda sensor with a voltage jump in the characteristic. When using this inexpensive sensor type, a change in the lambda value resulting from a change in the injection quantity has to be determined indirectly, for example, from the deviation of a lambda controller, because the voltage-jump sensor has only a voltage jump in the characteristic at lambda=1, i.e., unlike broadband lambda sensors, it does not allow lambda to be determined in continuous values.
Another embodiment of the method according to the present invention provides that the order of a regression polynomial underlying the orthogonal experimental plan is selected as a function of lambda. If, after an adjustment procedure using a regression polynomial of lower order, the desired value of lambda cannot be adjusted with sufficient accuracy, this embodiment allows selection of a higher-order regression polynomial to improve the accuracy of the adjustment method.
The method according to the present invention may be implemented in the form of a computer program which is designed for a control unit of an internal combustion engine, in particular of a motor vehicle. In this context, the computer program is executable, in particular, on a microprocessor, and suitable for carrying out the method according to the present invention. The computer program can be stored on an electric storage medium, such as a flash memory or a read only memory.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic block diagram of an exemplary embodiment of an internal combustion engine according to the present invention.
FIG. 2 is a flow chart of an example embodiment of the method according to the present invention.
FIG. 3 shows a chart illustrating a part of an orthogonal experimental plan including four influence variables.
DETAILED DESCRIPTION
FIG. 1 shows an internal combustion engine 1 of a motor vehicle, in which a piston 2 is able to move back and forth in a cylinder 3 . Cylinder 3 is provided with a combustion chamber 4 , which is bounded, inter alia, by piston 2 , an intake valve 5 , and an exhaust valve 6 . An intake pipe 7 is coupled to intake valve 5 , and an exhaust pipe 8 is coupled to exhaust valve 6 .
In the region near intake valve 5 and exhaust valve 6 , an injector 9 and a spark plug 10 extend into combustion chamber 4 . Injector 9 can also be located in intake pipe 7 .
Fuel can be injected into the combustion chamber 4 through injector 9 . The fuel in combustion chamber 4 can be ignited by spark plug 10 .
Accommodated in intake pipe 7 is a rotatable throttle blade 11 , by means of which air can be supplied to intake pipe 7 . The quantity of supplied air depends on the angular position of throttle blade 11 . The exhaust connectors of the individual cylinders 3 merge upstream of catalytic converter 12 , forming the exhaust pipe 8 , in which is located a lambda sensor 13 . Catalytic converter 12 serves to clean the exhaust gases resulting from the combustion of the fuel, and lambda sensor 13 measures the air-fuel ratio in exhaust pipe 8 .
During the operation of internal combustion engine 1 , fuel is injected through injectors 9 of the individual cylinders 3 into the associated combustion chambers 4 . Spark plugs 10 are used to create combustions in combustion chambers 4 , causing pistons 2 to reciprocate. These movements are transmitted to a crankshaft (not shown), and exert a torque thereon.
A control unit 15 receives input signals 16 representative of performance quantities of internal combustion engine 1 , which are measured by sensors. For example, control unit 15 is connected to an air-mass sensor, a speed sensor, and to lambda sensor 13 . Control unit 15 is also connected to an accelerator pedal sensor, which generates a signal that indicates the position of an accelerator pedal capable of being operated by a driver, and which signal thus indicates the requested torque. Control unit 15 generates output signals 17 , with which the performance of internal combustion engine 1 can be influenced via actuators. For example, control unit 15 is connected to injector 9 , spark plug 10 , and throttle blade 11 , and the like, and generates the signals required for the control thereof.
Control unit 15 is designed, inter alia, to control the performance quantities of internal combustion engine 1 in open loop and/or in closed loop. For example, the fuel mass injected by injector 9 into combustion chamber 4 is controlled by control unit 15 in open loop and/or in closed loop with a view to low fuel consumption and/or low pollutant emissions. For this purpose, control unit 15 is provided with a microprocessor, in which a computer program is stored in a storage medium, e.g., in a flash memory, the computer program being suitable for carrying out the aforementioned open-loop or closed-loop control.
FIG. 2 shows a flow chart of an example embodiment of the method according to the present invention for cylinder-specific adjustment of the injection quantity in an internal combustion engine, which method includes three method steps a), b), and c).
Method step a) of FIG. 2 includes the execution of an orthogonal experimental plan, of which the first four steps a1 through a4 are shown, by way of example, in the table of FIG. 3 .
The entire experimental plan has N steps (not all shown) and, according to the number of cylinders of a four-cylinder internal combustion engine 1 selected by way of example, includes four influence variables Z 1 through Z 4 , each of which acts on an associated output variable L_ai (i=1, . . . , N).
Influence variable Zk (k=1, . . . , 4) denotes the injection quantity of cylinder k, that is, the amount of fuel that is metered to cylinder k within the framework of the experimental plan.
Output variable L_ai corresponds to the lambda value of step i (i=1, . . . , N) of the orthogonal experimental plan, which is measured by a lambda sensor 13 in exhaust pipe 8 , and averaged over a sufficiently long period of time.
The purpose of the orthogonal experimental plan is to establish an analytical relationship between the lambda value in exhaust pipe 8 and the injection quantities of the individual cylinders 3 in as few steps as possible.
To this end, a quadratic regression function is defined using a polynomial formulation, the quadratic regression function being intended to model lambda as a function of the injection quantities.
A portion of a quadratic regression polynomial for the lambda value in exhaust pipe 8 as a function of the injection quantities of the four cylinders 3 is given below. For the sake of clarity, among higher-order terms in the expression, only those which contain the factor Z1 are shown.
lambda( Z 1 , Z 2 , Z 3 , Z 4 )= b 0 + b 1 * Z 1 + b 2 * Z 2 + b 3 * Z 3 + b 4 * Z 4 + b 11 * Z 1 * Z 1 + b 12 * Z 1 * Z 2 + b 13 * Z 1 * Z 3 + b 14 * Z 1 * Z 4 +. . .
To be able to determine the unknown coefficients bi (i=0, . . . , N), bij (i, j=1, . . , N, i<j), and bii (i=1, . . . , N), it is necessary to carry out N+1 steps of the experimental plan.
A step ai is to change the injection quantities for the four cylinders 3 , following the scheme Z 1 , Z 2 , Z 3 , Z 4 shown in FIG. 3 . After that, the lambda value L_ai resulting from this change is measured.
The change in the injection quantity is symbolized by ‘+’ and ‘−’, respectively, with ‘+’ describing an increase in the injection quantity of the corresponding cylinder 3 by, for example, 4%, and ‘−’describing a reduction by the same factor. The value selected by control unit 15 for the normal operation of internal combustion engine 1 is to be taken in each case as the initial value for this change in the injection quantity.
For example, in step a1 of FIG. 3 , the first three cylinders are charged with an injection quantity of only 96%, while the fourth cylinder receives 104%. The associated lambda value L 13 a1 is detected to be, for example, 1.03. This leads to the following equation:
L — a 1 =103%= b 0 + b 1 *96%+ b 2 *96%+ b 3 *96%+ b 4 *104%+ O ( Z*Z )
For the sake of clarity, the terms of the order Z*Z are combined to form the addend O(Z*Z).
Given a sufficiently high number N+1 of experimental steps yielding N+1 equations of the type mentioned above, it is possible to determine coefficients bi, bij, bii of the regression polynomial.
Usually, it is even possible to neglect several coefficients, e.g., coefficients of the higher-order terms, thus reducing the computational effort, which means that not all N experimental steps need to be carried out to determine the coefficients.
Knowing the coefficients of regression polynomial lambda(Z 1 , Z 2 , Z 3 , Z 4 ), it is possible to determine correction values for the injection quantity of each cylinder 3 in method step b) of FIG. 2 illustrating the adjustment method according to the present invention. These correction values correspond to the difference between the injection quantities determined as a solution of the equation lambda(Z 1 , Z 2 , Z 3 , Z 4 )=1 and the injection quantities selected by control unit 15 .
In method step c) of FIG. 2 , provision is made to adjust the injection quantity selected by control unit 15 for each cylinder 3 , using the correction values.
This adjustment process allows the use of more cost-effective injectors with far larger tolerances because it is possible to compensate for even extreme deviations of the properties of an injector by correcting the corresponding injection quantity.
The accuracy of the adjustment can be further increased by selecting a regression polynomial of higher order. Moreover, the order of the regression polynomial is selected as a function of the control performance of the lambda controller.
The measurement of the lambda value is carried out using a broadband lambda sensor 13 , which allows lambda to be determined in continuous values in an interval between lambda=0.7 and lambda=4.
The lambda value can also be measured using a voltage-jump sensor, whose characteristic shows a voltage jump at lambda=1. The voltage-jump sensor does not allow lambda to be determined in continuous values, but only detection of the transition from lambda <=0 to lambda >0, and vice versa.
To detect lambda with such a voltage-jump sensor, the injection quantity has to be increased, for example, starting from a first lambda value in the so-called “lean operation” (lambda >1) until the next voltage jump in lambda occurs, i.e., until the change from lambda >1 to lambda <1 takes place.
The increase in the injection quantity required for this is a measure for the first lambda value.
The correction values determined in method step b) of FIG. 2 illustrating the adjustment method according to the present invention are stored in control unit 15 , and can be retrieved when starting the motor vehicle, and used to correct the injection quantities.
The correction values can, for example, be stored in an EEPROM memory, which is frequently used for storing performance quantities in control units.
The adjustment method can be carried out for the first time immediately after the manufacture of the motor vehicle. It can also be carried out periodically during vehicle operation, or during maintenance, to allow short-term changes in the injection system to be taken into account in the adjustment.
|
A method for cylinder-specific adjustment of the injection quantity in internal combustion engines is provided, as well as an internal combustion engine with which the method may be implemented. The injection quantity per cylinder selected by the engine management is changed in a controlled manner following an orthogonal experimental plan. The effect of this change on the excess-air factor “lambda” is analyzed, allowing the formulation of a regression polynomial to determine necessary corrections of the injection quantity, which injection quantity is adjustable individually for each cylinder with a view to optimum combustion.
| 5
|
FIELD OF THE INVENTION
[0001] This invention relates to portable containers for diverse products such as food, paint, cleaning solutions, and construction materials and more particularly to providing a container that is designed to prevent a child from drowning in the event the child should happen to fall into the container when it is partially filled with water or other liquid.
BRIEF DESCRIPTION OF THE PRIOR ART
[0002] Bucket-like containers, notably those commonly referred to as “five gallon plastic pails” are used to various consumer products such as foods, paint, cleaning substances, and construction materials (note: as used herein the terms “bucket” and “pail” are synonymous). Five gallon plastic pails are open-head containers with a rated capacity of about 4.5 to about 5.5 gallons and are generally about 14 to about 15 inches high and between about 10.25 to about 11.25 inches in diameter. They have nearly straight sides and usually are manufactured of high density polyethylene. When emptied of their original contents, such plastic containers are often reused as pails by consumers. It has been determined that a five gallon pail with some liquid in it is a potential drowning hazard if left unattended where it can be reached by a curious toddler A toddlers as young as 8-months may be strong enough to pull him or her self up far enough to lean over the pail. Because toddlers are top heavy. As a consequence, when a toddler leans over to peer into a pail, there is a tendency for the child to topple head first. Because of its shape, size and sturdiness, a conventional flat bottom five gallon plastic pail containing some liquid may not tip over when a toddler falls into it. Should that occur, the toddler may be unable to extricate itself, with the result that he or she drowns in the liquid in the pail. It has been determined that such drownings can occur with only a few inches of liquid in the bottom of the pail. The United States Consumer Safety Product Commission has determined from reports of deaths and non-fatal incidents associated with 5 gallon buckets that the ages of victims ranges from 7 months to 24 months, with a median age of 11 months. The height and weight of the reported victims averaged about 28 inches and 22 pounds respectively. The average height of the liquid in the buckets was about 6 inches.
[0003] In view of such drowning incidents, efforts have been made to provide protection against drowning. Three such efforts are disclosed in U.S. Pat. Nos. 5,183,179, 5,513,770 and 6,024,244. In U.S. Pat. No. 5,183,179, the container is formed with a child drowning protection guard in the shape of a tapered tube that is integral with the bottom wall of the container and extends upwardly from the bottom wall. The projection has a height and a diameter such as to prevent the child from drowning in liquid in the container. In U.S. Pat. No. 5,513,770, the drowning protection feature is in the form of an insert which can be screwed into a pail and is operable to prevent a child's head from entering the pail while allowing conventional household implements to be inserted into and withdrawn from the pail. In U.S. Pat. No. 6,024,244, the protection against drowning is achieved by a weighted convex safety attachment for the bottom of a container. All of the foregoing attempts, while laudable, suffer from limitations. In the case of U.S. Pat. No. 5,513,179, the projection in the container complicates the manufacture of the container and limits the size of implements that can be inserted into the container to the side of the projection. In the case of U.S. Pat. No. 5,513,770, the addition of an insert adds to the cost. Also, that feature suffers from the limitation that the user may forget to apply the drowning protection insert, with the result that a child may still peer into the container and run the risk of drowning as described above. The weighted convex safety attachment for the bottom of a container disclosed in U.S. Pat. No. 6,024,244 suffers from the fact that it introduces an increased cost since it is a separate component that is added to a standard flat bottom container. Also although it introduces more weight to lower the center of gravity, it does so by an increase in the overall height. Also the convex base of the safety attachment has a flat center portion that rests on a floor or other supporting surface for the container and has a small diameter, with the combination of that small diameter and the convex shape insuring that the container is unstable when left unattended. Accordingly when the container is in normal use, e.g., when it is standing alone, a removable stabilizing collar, sized and shaped to-fit around both the lower side of the container and the convex safety attachment, is utilized to provide stability and prevent the container from tipping. The stabilizing collar adds to the cost and also complicates warehousing and shipping since the presence of the stabilizing collars hampers the stacking of filled containers one upon the other and the storing and/or shipping of empty containers in nested relation, i.e., one empty container inside of another.
OBJECTS AND SUMMARY OF THE INVENTION
[0004] The object of the invention is to provide an open-head, nestable container of circular cross-sectional configuration that is shaped so that (a) it will stand upright on a flat support such as a floor, shelf or shipping pallet and (b) in the event that the container contains some water or other liquid and a toddler leans forward into the container, e.g., in an attempt to retrieve a toy that has fallen into the container, the weight of the child on the container will cause the container to tip over, thereby spilling the contents and preventing the child from drowning in the container.
[0005] Another object is to provide a container design with child drowning protection that can be made in different sizes without requiring different size covers.
[0006] The foregoing objects are achieved by providing a container with a bottom wall that is contoured in a manner that provides positional stability for the container when it is empty or partially or fully filled, yet makes it easy for the container to tip over when a toddler leans over and reaches into the container. Containers embodying the invention may be provided with covers that facilitate stacking covered containers one on top of the other. Additionally, the containers are formed with an inclined sidewall, whereby to permit the open empty containers to be nested one inside the other. Other features of the invention are described or rendered apparent by the following detailed description of a preferred embodiment of the invention which is to be considered together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 is a side view in elevation of a container embodying the present invention;
[0008] [0008]FIG. 2 is fragmentary vertical sectional view of the same container displaced 90d degrees from the viewpoint of FIG. 1.
[0009] [0009]FIG. 3 is a plan view of the same container;
[0010] [0010]FIG. 4 is a sectional view of a cover for the container;
[0011] [0011]FIG. 5 is a bottom view of the cover;
[0012] [0012]FIG. 6 is a cross-sectional view of the upper end of the container with the cover attached; and
[0013] [0013]FIG. 7 is an enlarged view illustrating how the bottom end of one container is accommodated by the cover of another container.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] Referring to FIGS. 1 and 2, the illustrated container 2 comprises a sidewall 4 that is circular in cross-sectional configuration but is tapered with a slight draft, preferably a draft of approximately 4.5°, in order to facilitate nesting of one container inside of another container. As seen best in FIGS. 1 and 3, the upper end of the container is formed with a peripheral lip 6 that is undercut so as to serve as a catch for a cover 8 as described hereinafter. The outer side of the sidewall is formed with several radially-extending flanges 10 adjacent its top eng and below lip 6 . Two outwardly projecting ears 12 are formed integral with two of the flanges 10 at diametrically-opposed regions of the container. Ears 12 have holes 14 for receiving the ends of a curved bail (not shown) that serves as a handle and allows the container to function as a bucket or pail.
[0015] Still referring to FIG. 1, the bottom end of the container is curved and recessed so as to have an annular convex projecting section 20 that forms a continuation of the side wall and a recessed circular center section 22 that is substantially flat. For convenience of understanding, the junction of the convex section 20 with side wall 4 is indicated by the broken line 21 in FIG. 1. Preferably contoured section 20 has a single radius of curvature with the center of that radius being eccentric to the longitudinal axis of the container, i.e., the vertical center axis of the container as viewed in FIGS. 1 and 2. That radius of curvature has a magnitude that does not exceed and preferably is less than the diameter of recessed center section 22 . Center section 22 has a diameter that is between about 30% to about 50% of the minimum diameter of side wall 4 . Convex section 20 makes a circular line contact when rested on a flat supporting surface, e.g., a storage shelf, floor, deck or shipping pallet. The low point of convex section 20 , i.e., the portion of that section that makes a circular line contact with a flat supporting surface, has an effective diameter that does not exceed one-half of the maximum diameter of the container and preferably has a smaller value. Additionally that effective diameter of the low point of convex section 20 is no less than 25% of the maximum diameter of the container but less than the minimum diameter of side wall 4 . Preferably the low point of convex section 20 has a diameter of approximately 40-50% of the maximum outside diameter of the container. The foregoing requirements hold true for a container having a side wall of constant diameter and also a side wall that is inclined with a draft angle not exceeding about 5 degrees. If the side wall has a larger draft angle, the effective diameter of convex section 20 is increased as required to provide the proper balance of stability and tiltability when liquid is present in the container. Preferably center section 22 is recessed about 0.300 inch above the low point of convex section 20 but it may be recessed more or less than that amount.
[0016] In a preferred embodiment of the invention, the maximum inner diameter of the container at its top end is approximately 11.8 inches, its overall height is approximately 14.2 inches measured from the low point of the convex section 20 to its top end, side wall 4 has a draft angle of about 4.5 degrees, the minimum inside diameter of the side wall (i.e., where the side wall meets the convex section 12 ) is approximately 10.4 inches, the radius of curvature of convex section 20 in cross-section is approximately 2.5 inches, and recess section 22 has a diameter of about 3 inches and is recessed about 0.300 inch. With that design, the convex section 20 joins the side wall about 2.4 inches above the lowermost point of convex section 20 , and a virtual projection of the outer surface of the side wall has a diameter of approximately 10.3 inches at the level of the lowermost point of the convex section 20 . At the lip 6 the outside diameter of the container is approximately 12.0 inches and the thickness of the side wall is approximately 0.092 inch. The tiltability of the container when upright is a function of the effective diameter of the container measured at the low point of convex section 20 , and in the preferred embodiment that effective diameter is approximately 5 inches. A bucket having the foregoing dimensions holds approximately 5 gallons of water and is identified herein as a “five gallon” container.
[0017] It has been determined that the amount of horizontal force required to tip a bucket incorporating the present invention varies with the amount of water in the container. Measurements were conducted with a “five gallon” container having the dimensions described above with different amounts of water to determine the amount of horizontal force required to tip the bucket. The results of those tests are set forth in table I:
TABLE I Depth of Water Horizontal Force 6 inches 7 lbs 10 inches 8 lbs 13.5 inches 10 lbs
[0018] A conventional five gallon plastic container having a substantially flat bottom, e.g., a container an inner diameter of 11.8 inches at its top end, an inner diameter of 10.1 inches at its bottom end, a wall thickness of about 0.090 inch, and a height of about 14.1 inches, cannot not achieve comparable results for the reason that application of a horizontal force merely causes the container to slide horizontally on its flat bottom. In this connection it is to be noted that such flat bottom containers have a tendency to slide toward a toddler as the toddler grips it and tries to pull himself or herself up on it, causing a forward momentum of the toddler and increasing the likelihood that the toddler will fall into the container without it tipping over.
[0019] It is to be noted that the U.S. child safety laws with regard to pails contemplates a toddler of 22 months of age being able to stand up and access a pail filled with water, and a toddler of that age would weight approximately 26 lbs. Accordingly, the amount of force resulting from a toddler leaning into a container of the type described would be much greater than the 10 lbs. noted in Table I. Consequently if a child in the age of 22 months should stand up next to a pail made according to the present invention and then attempt to reach into or bend over into the pail, the pail would tip before the toddler could be put in danger of drowning in the contents of the container.
[0020] Turning now to FIGS. 4-7, the cover 8 comprises a crown section 30 and a rim section 32 . The latter section portion includes a depending skirt 34 that is formed with an inwardly directed projection 36 on its inner side for engagement with the lip 6 on the upper end of the container. The crown section of the cover is formed with a peripheral portion 38 that is recessed below the level of the upper surface of rim section 32 , a flat circular center portion 40 , and an annular portion 42 having a concave cross-sectional configuration disposed between sections 38 and 40 . The crown also has a circular depending flange 44 that is sized to make a close fit within the upper end of container 2 . Flange 44 acts to support the upper end of the container against radial compression. The concave annular portion 42 is shaped, sized and positioned to mate with the annular convex section 20 on the bottom side of a container 2 like the one shown in FIGS. 1-3, thereby allowing like containers 2 with like covers 8 to be stacked one upon the other. When so stacked, the nesting of the convex section 20 on the bottom of an upper container in the concave annular depression of annular portion 42 of a cover 8 on a lower container helps to restrain the covered containers from shifting laterally relative to one another in the stack. Additionally, since preferably the container sidewall is formed with a draft angle of approximately as herein illustrated and described, if the containers do not have their covers on, they may be nested inside one another to save space for shipping and storing purposes.
[0021] By way of observation, in the preferred embodiment of the invention the container has a height that is approximately 1.4 times the diameter of the virtual straight line projection of the side wall down at the level of the lowermost point of the annular convex bottom wall section 20 , and the portion of that annular protuberance that makes a circular line contact with a flat supporting surface has a diameter that is approximately 0.6 times the diameter of that virtual projection of the side wall at the level of the lowermost point of the convex annular protuberance. That ratio is offered as a guideline rather than a restriction with respect to practicing the invention.
[0022] An interesting aspect of the invention is that the capacity of the container described above may be changed without requiring a different size cover or altering the shape or dimensions of the bottom end of the container, i.e., the portion of the container below the bottom end of side wall 4 as represented by line 21 . More specifically, the container describe above can be modified to provide a capacity ranging from about 3.5 to about 6.5 gallons, without changing the diameter at the upper end of the container or the dimensions or contour of the convex projecting section 20 and/or recessed center section 22 , by (1) altering the height of the side wall 4 and (2) making an appropriate change in the draft angle of side wall 4 . It is contemplated that such change in capacity may involve providing side wall 4 with a single draft angle or a draft angle that changes from top to bottom, e.g., a first draft angle commencing where side wall 4 joins convex section 20 and extending for a limited distance along the length of side wall, and a second draft angle extending for the remainder of the length of the side wall. It is to be noted that, regardless of whether side wall 4 has a single or plural draft angle, modifying the container to provide a capacity of 3.5 or 6.5 gallons, for example, can be accomplished according to the invention without changing the diameter of the bottom end of side wall 4 , i.e., the diameter at the level of line 21 . Hence the specific mold design for the bottom of a 5 gallon container embodying the invention may be used unaltered for other containers of different total holding capacity.
[0023] A primary advantage of the invention is that it provides drowning protection for a child. Additionally, it offers the advantage that existing container designs may be modified to incorporate a contoured bottom wall as herein described, and that such containers embodying the invention would be no more expensive to manufacture than that of a conventional flat-bottomed container of comparable size and of like purpose. Furthermore the containers may be filled and the covers attached thereon using conventional filling and capping machinery. Still another advantage is that although the invention as been described and illustrated in connection with so-called 5 gallon pails, it may be embodied in containers of other sizes and also containers that lack ears as shown as 12 for accommodating bails or handles and hence are not designed to serve as pails or buckets. For example, the containers may be formed with a pair of diametrically opposed projecting portions that can serve as grips or handles for lifting the container. Accordingly the particular dimensions and curvature values set forth above may be changed for containers of smaller or greater dimensions. It also is contemplated that the invention may be practiced with containers having straight rather than tapered side walls.
[0024] Other possible modifications and advantages will be obvious to persons skilled in the art.
|
A container is provided with child drowning protection in the form of a bottom wall that is contoured in a manner that (1) allows it to stand upright on a flat support such as a floor, shelf or shipping pallet, and (2) in the event that the container contains some water or other liquid and a toddler leans forward into the container, e.g., in an attempt to retrieve a toy that has fallen into the container, the weight of the child on the container will cause the container to tip over, thereby spilling the contents and preventing the child from drowning in the container. Containers embodying the invention may be provided with covers that facilitate stacking covered containers one on top of the other. Additionally, the containers may be formed with an inclined sidewall, whereby to permit a plurality of open empty containers to be nested one inside the other.
| 1
|
BACKGROUND OF THE INVENTION
[0001] The present invention relates to improvements in polyester fiberfill batts, structures and articles made therefrom, and in particular, where the fiberfill comprises a copolymer of polyethylene terephthalate and poly(ethylene napthalate) (PETN). These articles provide superior bulk retention on exposure to high temperature.
FIELD OF INVENTION
[0002] The present invention relates to improvements in polyester fiberfill batts, structures and articles made therefrom. These articles provide superior bulk retention on exposure to high temperature. The articles are suitable for both domestic and industrial end uses, such as pillows, sleeping bags, car seats, boil-washable bedding, insulation, quilts, apparel, filters and the like.
BACKGROUND OF THE INVENTION
[0003] Japanese patent JP 11335452A discloses fibers from naphthalene dicarboxylic and aromatic diol alkylene oxide having improved fatigue resistance. U.S. patent 20020132960A1 discloses binary and ternary blends by mixing of cellulose esters and aliphatic/aromatic copolyesters to obtain fibers. However, neither of these references discloses fibers which are made from a copolymer of poly(ethylene terephthalate) and poly(ethylene napthalate), (PETN). In addition, neither of these references discloses filling materials obtained from the fibers produced.
[0004] Combining a flake of poly(ethylene napthalate) and a flake of poly(ethylene terephthalate) has been done to form articles such as bottles and films. With this process, a blend is produced. However, the compositon of the blend depends on the degree of transesterification which occurs during the extrusion process between the poly(ethylene napthalate) and the poly(ethylene terephthalate). Incorporation of naphthalate groups in to the poly(ethylene terephthalate) improves the strength modulus, heat resistance, gas barrier and UV barrier properties.
[0005] It is also known in the art that exposure to filling material at high temperature (50-100° C.) greatly reduces bulk retention. This is a major deficiency in applications where the material is subject to high temperatures, e.g., car seats and boil-washable bedding for medical end use. In addition the incumbent material such as polyurethane foam can be difficult to recycle.
SUMMARY OF THE INVENTION
[0006] Applicants have found that fibers comprising a copolymer of poly(ethylene terephthalate) and poly(ethylene napthalate), (PETN) can be used to produce articles which provide superior bulk retention on exposure to high temperature. Preferably, such fibers have a dpf in the range of 1-15. The fibers may be of round and hollow, scalloped oval, trilobal or four-hole cross section. These fibers comprise 5 mole % to 20 mole % naphthalate groups and the remainder of the dicarboxylate groups as terephthalate. Such fibers show the property of superior compression performance of initial bulk (BL 1 ) and residual bulk (BL 2 ) than incumbent homopolymer polyester fiberfill.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 shows the property of compression performance of initial bulk, BL 1 , performance of batts as a function of concentration and of unit naphthalate group (mole %) and temperature.
[0008] FIG. 2 shows the the property of compression performance of residual bulk, BL 2 , of batts as a function of concentration and of unit napthalate group (mole %) and temperature.
DETAILED DESCRIPTION OF THE INVENTION
[0009] The present invention is directed to fibers comprising a copolymer of poly(ethylene terephthalate) and poly(ethylene napthalate), (PETN). Dimethyl terephthalate (DMT) and naphthalene di carboxylate (NDC) are reacted with ethylene glycol (EG) to form such PETN copolymers. Specifically, DMT is reacted with an excess of EG in the presence of a manganese catalyst. Methanol is distilled from the mixture to give a low molecular weight polyethylene terephthalate (PET) oligomer. Phosphoric acid is then added to this oligomer to deactivate the ester interchange manganese catalyst. Antimony trioxide is added as polycondensation catalyst for the next stage of the reaction. Cobalt acetate is added at this point as a blue color toner for the polymer. The next stage occurs under reduced pressure, and the oligomer chains combine, evolving ethylene glycol. The reaction is complete once the required viscosity of the polymer is achieved.
NDC shown below reacts in an analogous manner to DMT.
[0011] PETN polymers containing 5, 10, 15 and 20 mole % of the acid units as naphthalate may be prepared according to the present invention. PETN5 is taken to mean 5% of the acid units are naphthalate groups, and similar designations can be given for the 10, 15 and 20 % of the acid units being naphthalate groups. The polymer of the present invention is formed into a flake. The flake is then crystallized in a fluid bed to prevent sticking/sintering, then dried and spun into fibers. The fibers of the present invention comprise in the range of 1 mole % to 30 mole % napthalene di-carboxylate and the remainder of the dicarboxylate moieties as terephthalate. The fibers have a denier per filament in the range of 1-30. The fibers may have a round, scalloped oval, hollow, trilobal hollow or four-hole cross section.
[0012] The fibers may be drawn and cut to the desired dpf and cut length. The cut fibers are then converted into clusters. The clusters may comprise a blend of dry PETN fibers of the present invention and slickened PETN fibers of the present invention. The clusters are carded and converted into a batt of either a cross-lapped or a vertical folded configuration. The bulk properties of batts of this invention are determined by compressing the clusters ooon an Instron tester and determining the height under load. The test, which is hereinafter referred to as the total bulk range measurement (TBRM) test, is described below, in the Test Methods section. Initial bulk, BL 1 , and a residual bulk, BL 2 , are measured with this TBRM test. It has been found that preferably, the batts of the present invention have an initial bulk, BL 1 , in the range of 4.2 to 5.1, and a residual bulk, BL 2 , in the range of 0.47 to 0.50.
[0013] In general, Applicants have found that the use of fibers according to the present invention in batts resulted in the following:
[0014] BL 1 improves strongly on the addition of naphthate groups.
[0015] BL 1 reduces as temperature increases.
[0016] BL 1 is insensitive to time of exposure.
[0017] BL 2 improves strongly with the addition of naphthalate groups.
[0018] BL 2 is insensitive to temperature and time of exposure.
[0019] Applicants have found that the optimum concentration for BL 1 is 10 mole % PEN, while for BL 2 it is 20 mole %. This optimum behavior can be linked to the shrinkage properties of the polymer. The amount of polymer chain mobility is linked to the amount the temperature is above T g . As the level of napthalate in the polymer increases, T g increases. Therefore, the polymer chain mobility will decrease for a given temperature above T g with increasing naphthalate content. This reduction in chain mobility could reduce the shrinkage seen in fibers at a given temperature above T g . Therefore, Applicants have found that increasing napthalate content can reduce shrinkage and improve the bulk performance.
[0020] Alternatively, increasing the level of naphthalate will reduce the crystallinity that is developed in the polymer. This will reduce the number of pinning points holding the orientated polymer chains in position, so on exposure to heat some of these orientated chains will relax, and the polymer will shrink. In this case increasing the naphthalate level will increase shrinkage and will worsen the bulk properties. With these alternative mechanisms occurring at the same time, one can expect to see a maximum in the bulk performance with increasing naphthalate level.
[0021] The invention will be described in greater detail with reference to the following examples which are intended to illustrate the invention without restricting the scope thereof.
Test Methods
[0022] Total bulk range was measured as follows with the TBRM test. This test is carried out by cutting 6-inch (15.25 centimeters) squares from a carded web and adding them to a stack in a cross-lapped manner until their total weight is 20 grams. The entire area is then compressed in an Instron under a load of 50 pounds (22.7 kilograms). The stack height is recorded (after one conditioning cycle under a load of 2 pounds) for heights at loads of 0.001 (for BL 1 ) and 0.2 (for BL 2 ) pounds per square inch (0.00007 and 0.014 kilograms per square centimeter, respectively) gage. BL 1 is the initial height, or bulk, and is a measure of filling power, and BL 2 is the height under load, or residual bulk, and is a measure of support.
EXAMPLE 1
[0023] PETN10 was prepared as follows. PETN polymers containing 10 mole % of the end units as naphthalate were prepared in the 40-gallon autoclave and crystallized using the fluid bed. Dimethyl terephthalate (DMT) (63 kg), dimethyl 2,6-naphthalene dicarboxylate (8.8 kg), ethylene glycol (42 L) and manganese acetate. 4H 2 O (430 ppm, 29.7 g) were placed in a 40-gallon polymerization reactor under nitrogen. The mixture was heated slowly with stirring and the reflux column mid-point set to 90° C. to enable the methanol generated to be evolved from the reaction. After 20 L of methanol were collected, the column mid-point was set to 220° C. and the reaction temperature increased to 230° C. Once a temperature of 230° C. was achieved 85% phosphoric acid (250 ppm, 20.6 g) in 200 ml ethylene glycol was added and allowed to react in to the mixture for 5 minutes prior to transfer to a second autoclave. Antimony trioxide (400 ppm, 27.8 g) cobalt acetate4H 2 O (150 ppm, 10.4 g) in 700 ml ethylene glycol were then added to the reaction mixture. The mixture was heated to 290° C. under vacuum and the polymerization continued until a stirrer kW load of 4.4 was achieved at 40 rpm. The polymer was finally cast into water and chipped to yield approximately 57 kg amorphous polymer.
[0024] The flake was crystallized in a fluid bed to prevent sticking/sintering then dried prior to spinning into fibers. The fluid bed conditions were gradually increased from 40-100° C. in 30 min, 110-150° C. in 8 hours, 150-100° C. in 1 hour and 100° C. to 40° C. in 1 hour. The crystallized flake was spun at 280° C. into 18 dpf (nominal) fiber and subsequently drawn to 6 dpf (nominal) fiber. The physical properties were: LVR=16.97, Mod=29.8 gpd, TEN=2.75 g/d, CPI=6.4, CTU=30.8%, BOS=1.2%. The Tg of the flake was 83.4° C. relative to 75° C. for control homopolymer PET of LRV=21.
[0025] The drawn fibers were cut, carded and made into batts.
[0026] Batts were prepared and then exposed to the following conditions:
0≦Naphthalate Conc(mol %)≦20
40° C.≦Temperature (° C.)≦90° C.
0≦Time (hours)≦72
The samples were withdrawn from the oven at 8-hour frequency. BL 1 , initial bulk, at a load of 0.001 lbs, and BL 2 , residual bulk at a load of 0.2 lbs, were measured. The results are illustrated in FIGS. 1 and 2 .
[0028] The performance of the control (batts made from fibers comprising a homopolymer versus batts made from fibers comprising PETN10) on exposure to high temperature at various time intervals is indicated below:
Temp. 8 hrs. 24 hrs. 48 hrs. 72 hrs. ° C. BL1 BL2 BL1 BL2 BL1 BL2 BL1 BL2 TDM#8239A 40 3.751 0.338 4.024 0.348 4.116 0.348 4.018 0.345 (Control) TDM#8239C 40 5.196 0.470 5.117 0.477 5.091 0.473 5.064 0.467 (PETN10) TDM#8239A 80 3.866 0.350 3.822 0.351 3.570 0.360 3.832 0.374 (Control) TDM#8239C 80 4.535 0.485 4.428 0.487 4.440 0.490 4.465 0.493 (PETN10) TDM#8239A 90 3.588 0.355 3.496 0.371 3.420 0.345 3.358 0.363 (Control) TDM#8239C 90 4.518 0.498 4.366 0.505 4.640 0.509 4.239 0.501 (PETN10)
[0029] The results indicate that PETN10 fibers show a greater than 25% improvement in BL 1 and greater than 35% improvement on BL 2 on exposure to high temperature versus control.
EXAMPLE 2, 3 AND 4
[0030] PETN5, 15 and 20 copolymers were also prepared in a similar manner to that described above in Example 1. The levels of DMT and NDC were as follows: 66.5 kg of DMT and 4.4 kg of NDC were used; for PETN15, 59.5 kg of DMT and 13.2 kg of NDC were used; and for PETN20, 56 kg of DMT and 17.6 kg of NDC were used. For all of these polymers, and for the polymers prepared in Example 1, a mole ratio of 2.1:1 was used, i.e., 2.1 moles of alcohol were added for every mole of dimethylester.
[0031] Drawn fibers were produced, cut, carded and made into batts. BL 1 and BL 2 were measured as described above, and the measurements are shown in FIGS. 1 and 2 .
|
The present invention is directed to fibers comprising a copolymer of polyethylene terephthalate and poly(ethylene napthalate) (PETN). These fibers are used in polyester fiberfill batts, structures and articles made therefrom. Such articles provide superior bulk retention on exposure to high temperature.
| 3
|
FIELD OF THE INVENTION
The present invention relates to a device for drawing in a printing material web into a rotary printing press. One end of the printing material web can be connected to a draw-in element by using at least one reinforcement element.
A device for drawing in a printing material web is known from DE 297 10 607 U1. In this device, a wedge-shaped reinforced element is used for forming a draw-in tip.
U.S. Pat. No. 4,063,505 describes a device for drawing in a web of material by means of two tapes. A start of the web of material is maintained in a frictionally connected manner between the two tapes.
GB 2 256 854 A discloses a device for drawing in a printing material web by means of a reinforcement element. Here, the reinforcement element and the printing material web are connected by means of staples.
Later published DE 198 16 510 A1 discloses a draw-in tip, which is wrapped by the corners of the start of a web.
SUMMARY OF THE INVENTION
The object of the present invention is directed to creating devices and a method for the drawing in a printing material web.
In accordance with the present invention, this object is attained by a device and method in which one end of the printing material web which is to be drawn into a rotary printing press can be connected to a draw-in element by using at least one reinforcement element. This reinforcement element has catches on its side facing the web, or has a closable loop. The end of the printing material web and the reinforcing element are connected by the catches or by the loop.
A simply produced draw-in tip with a small number of adhesives is achieved, in an advantageous manner, by the device in accordance with the present invention. Only a small portion of the tractive forces is transmitted by the adhesives. An interlocking connection occurs between the reinforcement element and the free end of the material to be imprinted.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention are represented in the drawings and will be described in greater detail in what follows.
Shown are in:
FIG. 1, a schematic representation of a device for drawing in a printing material web in accordance with a first preferred embodiment of the present invention,
FIG. 2, an enlarged section in accordance with FIG. 1 in the area of the draw-in means,
FIG. 3, the schematic representation of a device for drawing in a printing material web in accordance with a second preferred embodiment,
FIG. 4, an enlarged portion in accordance with FIG. 3 in the area of the draw-in means,
FIG. 5, a schematic representation of a device for drawing in a printing material web in accordance with a third preferred embodiment, and in
FIG. 6, a schematic section in accordance with claim 5 in the area of an engagement element.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The start of a printing material web 01 , for example a paper web, is provided with a draw-in tip 02 for drawing this printing material web 01 along a prepared guide path into a web-fed rotary printing press, for example. This draw-in tip 02 has a reinforcement element 03 . In the present preferred embodiment, this reinforcement element 03 is embodied as a generally wedge-shaped plate having a thickness d 03 of, for example 1 mm and having a length 103 along its linear edge 17 of, for example 1.5 m, all as seen in FIGS. 1 and 2. This reinforcement element 03 can be deformed, for example vertically reversible in respect to the conveying plane, and is made using a rubber-elastic material. The reinforcement element 03 preferably is made, for example, of a foil-like plastic material, such as, for example PA, PE, PVC, PTFE.
T-shaped or L-shaped reinforcement elements can also be used in place of a generally wedge-shaped reinforcement element 03 . All of the contemplated shapes of the reinforcement element 03 have in common that a first, or attachment end 04 of a first width bO 4 , for example of 150 mm, is greater in comparison with a second or coupling end 06 , having a second width bO 6 of, for example 50 mm, of the reinforcement element 03 .
The second or coupling end 06 of the reinforcement element 03 is provided with a coupling device for the selective fastening of the reinforcement element 03 to a draw-in element 07 of, for example, a web-fed rotary printing press.
This coupling device can be designed, for example, as a coupling loop 08 , or as a coupling eye, which is able to be fastened to a catch 09 of the draw-in element 07 .
In the present first preferred embodiment, the coupling loop 08 is formed by turning over or doubling back the second, free coupling end 06 of the reinforcement element 03 . A turned-over or doubled back portion 11 of the second, free coupling end 06 of the reinforcement element 03 is again connected with the reinforcement element 03 . This connection can be made by means of a hook-and-eye strip 12 , as depicted in FIG. 2 . In this case, in its stretched state the second, free coupling end 06 has on one side both of the partial elements; i.e.the hook strip 13 and eye strip 14 of the hook-and-eye strip 12 , which partial elements 13 and 14 are arranged at a distance from each other. After turning the end 06 over, thus doubling it back on itself, the hook strip 13 is connected with the eye strip 14 . In this way, a loop 08 is formed, which loop 08 can then be selectively opened and closed.
The opening and closing of the loop 08 can take place multiple times without destroying the material of the reinforcement element 03 in the process.
A magnetically acting connection, such as two magnets acting together, or one magnet acting together with a metal piece, or a snap fastener connection can be provided in place of a hook-and-eye strip 12 for forming such a loop 08 , which magnetically acting connection or snap fastener connection is selectively opened and closed.
To form the draw-in tip 02 , the reinforcement element 03 , together with a front edge 18 of the free end 16 of the printing material web 01 extending transversely in respect to the conveying direction, forms an opening angle a in the range between 45° to 85°. A corner 21 of the printing material web 01 , defined by the lateral edge 19 facing away from the front edge 18 and remote from the draw-in element 07 , is temporarily held manually on the reinforcement element 03 or is connected with the reinforcement element 03 by means of an adhesive strip or an insertable tongue.
Starting at this remote corner 21 , the reinforcement element 03 is turned over several times, so that the printing material web 01 is wrapped at least once completely around the reinforcement element 03 . The free end 16 of the printing material web 01 is preferably wrapped around the reinforcement element 03 in several layers. In the course of this enwrapment, the reinforcement element 03 travels or moves laterally across the web 01 from the remote lateral edge 19 of the printing material web 01 , which faces away from the draw-in element 07 , to the proximal lateral edge 22 of the printing material web 01 , which is close to the draw-in element 07 .
The reinforcement element 03 turned-over or enwrapped in web 01 in this way is joined together with web 01 , for example by means of an adhesive strip 23 , so that the layers 24 of the printing material web 01 which surround reinforcement element 03 are connected with the free end 16 of the printing material web 01 .
A proximal corner 26 of the free end 16 of the printing material web 01 , which faces or is proximal to the draw-in element 07 , can be folded in, to now be facing away from the draw-in element 07 , and can also be secured on the free end 16 of the material web 01 by means of the adhesive strip 23 , all as seen in FIG. 1 .
The draw-in tip 02 formed in this way is now connected with the draw-in element 07 .
This draw-in element 07 can be embodied, for example, as a chain 28 as depicted in FIG. 1, and has catch 09 , embodied as a suspension clip 29 , which extends out from chain 28 in the axial direction, i.e. perpendicularly in relation to the conveying direction T. An opening 31 or a hook for fastening the draw-in tip 02 is provided in this suspension clip 29 .
The draw-in element 07 can also be embodied as a tape 32 , as shown in FIG. 3 and in FIG. 4, for example, on which loops 33 , or in which slits are arranged.
Now the second, free or coupling end 06 of the draw-in tip 02 can be threaded through the opening 31 or the loop 33 of the draw-in means 28 , 32 , respectfully. This second, free or coupling end 06 , once passed through the opening 31 , 33 of the draw-in means 28 , 32 , is now turned over in the direction toward the draw-in tip 02 and is joined or doubled back on itself by means of the hook-and-eye strip 12 to form the coupling loop 08 .
In a further preferred embodiment as seen in FIG. 5 and in FIG. 6, catches 36 , which penetrate through the printing material web 01 , are attached to a first side of a reinforcement element 34 facing the printing material web 01 . The catches 36 are of a length 136 which is of at least the maximal thickness d 01 of a printing material web 01 to be drawn in, a thickness d 36 , of for example 0.1 mm, extending in the conveying direction T, and a width b 36 , for example 10 mm, extending perpendicularly in respect to the conveying direction, as seen in FIGS. 5 and 6.
A counter element, acting as a female element 37 , is associated with this reinforcement element 34 , which acts as a male element 34 and which is provided with the previously discussed catches 36 . This female element 37 has openings 38 matched to the catches 36 . To form a draw-in tip 39 , the free end 16 of the printing material web 01 , for example, is placed on the female element 37 , and the printing material web 01 is penetrated by means of the catches 36 of the male element 34 . Now the female element 37 and the male element 34 are releasably connected with each other, for example magnetically, or by means of snap closures or by means of a hook-and-eye strip.
While preferred embodiments of a device for inserting a strip of fabric to be printed or for drawing in the strip of fabric or the printing material web into a rotary printing press, in accordance with the present invention have been set forth fully and completely hereinabove, it will apparent to one of skill in the art that a number of changes in, for example the specific rotary printing press, the drive for the draw-in device and the like could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the following claims.
|
A material web to be printed is drawn into a rotary printing press by securing a reinforcement element to a leading end of the material web. The reinforcement element can be enwrapped in the material web or held to the web by suitable catches. An openable and closable loop is formed in the reinforcement element and is used to connect the element to the web draw-in device of the printing press.
| 1
|
BACKGROUND OF THE INVENTION
[0001] The invention relates to a method for recognizing and avoiding premature combustion events.
DESCRIPTION OF THE PRIOR ART
[0002] In known applications of knocking control systems, internal combustion engines are operated permanently with variable ignition angles that are individual to the cylinder, with the ignition angle being adjusted in the direction of “early” from knock-free operation until knocking is recognized. Then there is a reversal of the ignition point in the direction of “late”, leading to the avoidance of knocking as a result of the thus ensuring temperature reduction in the combustion chamber. After the adjustment to late of the ignition to secure knock-free operation, the same is adjusted again in the direction to “early” according to an up-regulation strategy, i.e. in the direction of the increased tendency towards knocking.
[0003] By using a knocking sensor for recognizing knocking and the associated optimized feedback control strategy, the internal combustion engine is operated as close as possible to the knocking threshold. As a result of a too quick adjustment to early of the ignition angle to the knocking threshold after a knocking event for example, there may be an increase in the thermal load in the combustion chamber as a result of the reduced cooling period. This feedback control strategy which is designed to minimize efficiency losses can initiate a premature combustion after a certain period of time. Premature combustions also additionally occur especially in charged high-performance spark-ignition engines through deposits for example or by unburned fuel or oil in the combustion chamber.
[0004] These premature combustions do not cause typical knocking features and are therefore not detected by currently used knocking sensors and their signal processing systems. Since a premature combustion entails a strong pressure increase in the compression phase and strongly increased combustion temperatures, such abnormal combustion processes lead to engine damage within a short period of time.
[0005] It is known from DE 100 43 700 A1 and DE 199 08 729 A1 to reduce knocking, i.e. abnormal combustion processes, by knock-reducing measures such as shifting the ignition point to late or by performing multiple injections. These measures influence only abnormal combustion processes which are initiated by the ignition spark, but not the premature combustions which are more hazardous to the internal combustion engine and which are not initiated by the ignition spark. Premature combustions cannot be influenced by shifting the ignition to late.
[0006] It is further known to reduce knocking by increased exhaust gas recirculation, see JP 58-025559 A.
[0007] JP 62-251450 A describes a device for reducing knocking, with different knock-prevention measures being taken in the high-load range and under acceleration in the part-load range. The quantity of the air intake is reduced in the full-load range and in the part-load range there is a shift of the ignition point to late.
SUMMARY OF THE INVENTION
[0008] It is the object of the invention to perform a secure and simple recognition of premature combustion for an internal combustion engine and to subsequently avoid premature combustion.
[0009] This is achieved in accordance with the invention by the following steps:
Providing at least one sensor and/or an electronic evaluation circuit for the immediate and direct recognition of premature combustion; direct recognition of premature combustion; performing at least one measure for avoiding premature combustion when premature combustion is recognized.
[0013] It may be provided that the recognition of premature combustion occurs by permanent monitoring of the sensor signal within a defined measuring window and by evaluation of the sensor signal, preferably by means of an integral process and/or maximum evaluation process. In a simple embodiment of the invention it can be provided that a cylinder pressure sensor signal, an acceleration sensor signal and/or a knock sensor signal is used as a sensor signal, with a premature combustion preferably being detected when cylinder pressure detected prior to the ignition point and/or the rise of the cylinder pressure before the ignition point exceeds a defined threshold value.
[0014] Preferably, the immediate and direct recognition occurs by monitoring at least one engine parameter influenced directly by the premature combustion, preferably the pressure curve in the cylinder. The invention makes use of the fact that a premature combustion is linked to a strong rise in pressure in the compression phase. It is possible to draw clear conclusions to premature combustion through the occurrence of this characteristic strong rise in pressure in the compression phase. It is irrelevant for the recognition of the premature combustion whether the premature combustion occurs with or without knocking.
[0015] The permanent monitoring can also occur by means of an electronic evaluation circuit by evaluating the ionic current at the spark plug. A cylinder pressure sensor is not mandatory here. It is possible to draw conclusions for premature combustion based on the progress of the ionic current signal after the end of the ignition spark. In the case of normal combustion there is a certain known distance between the end of the ignition spark and the time of maximum peak pressure (ionic current signal). The ionic current signal has a characteristic curve, with the ionic current dropping suddenly after the end of the ignition spark and with the drop being followed by a first maximum value that can be associated to chemical ionization and, at a distance from the spark end, a higher second maximum value that can be associated with thermal ionization. In the case of irregular combustion, this distance is considerably reduced or even smaller than or equal to zero. It is possible to deduce irregular combustion from this signal too. An additional possibility is offered by the amplitude of the ionic current signal. The higher the signal, the higher the thermal load. In the case of progressing (continued) irregular combustion, the ionic current signal would rise strongly. Measures can also be derived from this effect.
[0016] If very early combustion occurs (start of combustion very clearly before the ignition point or early in the compression phase), these two maximum values are not very distinctive. In the case of very early combustion, which typically occurs without any knocking because at the time of exceeding the knocking threshold the entire fuel has been combusted or the flame has reached the combustion chamber wall, the ionic current signal curve has a substantially continually dropping progress after the spark end by the falling thermal signal, without extreme values. If premature combustion occurs in combination with knocking (knocking as a consequence of premature combustion, but still with unburned mixture in the combustion chamber after exceeding the knocking threshold), then a maximum value in the ionic current signal can be determined as a consequence of thermal ionization which occurs much earlier than in the case of normal combustion and whose amplitude is substantially higher than in the case of regular combustion.
[0017] Premature combustion without knocking events can thus be determined in such a way that the ionic current signal after the spark end drops continually within the measuring window, without maximum values occurring.
[0018] A premature combustion with knocking events can be recognized when a maximum value of the ionic current signal which can be allocated to the combustion peak pressure lies above a defined threshold value and/or occurs within a defined period after the end of the spark.
[0019] It is further possible that an acceleration sensor signal is used as a sensor signal, with the evaluation of the sensor signal preferably occurring by a maximum evaluation process.
[0020] A fourth embodiment of the invention provides that a knock sensor is used as a sensor signal, with the evaluation of the sensor signal preferably occurring by a maximum evaluation process.
[0021] It can further be provided that a speed signal is used as a sensor signal, with the recognition of premature combustion occurring as a result of angular acceleration values derived from the speed sensor signal. Premature combustion leads to a rise in the cylinder pressure clearly before top dead center. As a result of this clearly too early rise in the cylinder pressure, the force acting via the connecting rod on the crankshaft changes. The torque generated by this one cylinder decreases or rises depending on the starting position of the combustion relative to the optimum. The rotational non-uniformity of the crankshaft changes, which means that the angular acceleration of the crankshaft decreases or increases as a reaction to the premature combustion in a cylinder. It is possible to define a bandwidth of permissible rotational non-uniformity, outside of which irregular combustion can be diagnosed. The detection of irregular combustion via rotational non-uniformity can be used together with other measures of detection of irregular combustion or later combustion (recognition of misfires).
[0022] An effective measure for preventing premature combustion consists of reducing the engine load of at least the pertinent cylinder. It can preferably be provided that the reduction of the engine load is performed at least partly by leaning out or enriching the respective cylinder.
[0023] As an alternative to this or in addition it can be provided that the reduction of the engine load occurs at least partly by reducing the intake manifold pressure.
[0024] If the premature combustions exceed a certain frequency, there must be reduction in the engine load in order to avoid endangering the internal combustion engine.
[0025] In an older patent application of the applicant it was proposed to perform at least one examination step for distinguishing between a spark-induced normal knocking event and a premature combustion only in the case of the occurrence of a knocking event.
[0026] It was checked whether the amplitude of the knocking event lies above a first knocking threshold for normal knocking. It was further checked whether the amplitude of the knocking event lies above a defined second knocking threshold for premature combustion. The knocking event was only identified as premature combustion on exceeding the second knocking threshold. By providing a knocking sensor and through the joint use of the evaluation circuit and amplifying steps there are certain limitations in the recognition of premature combustion, which in the worst case leads to the failure to recognize premature combustion.
[0027] The performance of such examination steps is not necessary in the present method because the recognition of premature termination occurs directly through the pressure increase during the compression phase and by the ionic current progress after the end of the spark, and not by comparing the amplitudes with defined knocking thresholds. This allows recognizing premature combustion relatively quickly and implementing respective countermeasures immediately. Damage as a consequence of premature combustion can thus be prevented especially effectively.
[0028] Furthermore, as a result of this method of immediate recognition of premature combustion, the likelihood of false recognitions decreases (initiation of measures without occurrence of premature combustion).
[0029] The recognition of premature combustion occurs preferably completely independently of the recognition of a knocking combustion. That is why premature combustion can occur only when no knocking event occurs.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The invention is now explained in closer detail by reference to the drawings, wherein:
[0031] FIG. 1 shows the pressure curve in a spark-induced combustion with knocking;
[0032] FIG. 2 shows the pressure curve in a premature combustion with knocking;
[0033] FIG. 3 shows the pressure curve during a premature combustion without knocking;
[0034] FIG. 4 a shows the cylinder pressure signals for regular and irregular combustions, and
[0035] FIG. 4 b shows ionic current signals for regular and irregular combustion processes.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] FIGS. 1 to 4 a show the cylinder pressure p entered over the crank angle KW.
[0037] As is clearly shown in FIG. 1 , a pressure increase occurs only after the ignition point ZZP in the case of knocking combustion 2 . This increase in pressure after the ignition point ZZP is thus a characteristic feature of knocking combustion.
[0038] The reference pressure curves with regular combustion are designated with reference numeral 1.
[0039] The pressure curve in the case of premature combustion 3 , 4 differs substantially from the same, as is shown in FIGS. 2 and 3 .
[0040] FIG. 2 shows a premature combustion 3 with knocking. The feature of this premature combustion is that the pressure increase occurs before the ignition point ZZP. A too strong pressure increase before the ignition point ZZP leads to the consequence that a strongly superimposed knocking is initiated when at the time of the exceeding of the knocking threshold there is still unburned mixture in the combustion chamber.
[0041] FIG. 3 shows a premature combustion 4 without knocking. In this case too, the pressure increase occurs clearly before the ignition point ZZP. Since in this first phase of the combustion the ignitable mixture has been combusted entirely, there is no superimposed knocking.
[0042] Since a premature combustion, with or without knocking, is linked to a strong pressure increase in the compression phase, a distinct recognition of premature combustion with or without knocking can occur at a very early stage, namely in real time, by monitoring the pressure curve in the compression phase.
[0043] As an alternative or in addition to the evaluation of the cylinder pressure, the recognition of the premature combustion can also be made on the basis of an ionic current signal i at the spark plug, as is shown in FIGS. 4 a and 4 b . The cylinder pressure signals p and the ionic current signals i are shown over the crank angle KW for regular combustion 1 and premature combustion 3 , 4 .
[0044] It is possible to conclude premature combustion from the curve of the ionic current signal i after the end EZ of the spark. In the case of a normal combustion 1 , the ionic current signal i has a characteristic curve, with the ionic current signal i dropping suddenly after the end EZ of the spark. The drop of the ionic current signal i is followed by a first maximum value 1 a which can be allocated to chemical ionization. A higher second maximum value 1 b which can be allocated to thermal ionization follows at a distance a to the spark end EZ, the occurrence of which coincides with the combustion peak pressure. When a premature combustion 3 , 4 occurs, these two maximum values 1 a , 1 b are not distinct.
[0045] When premature combustion 3 occurs in combination with knocking, a maximum value 3 a can be noticed in the ionic current signal i as a result of thermal ionization, which occurs however earlier than in the case of normal combustion 1 . The amount of maximum value 3 a is substantially larger than the maximum values 1 a and 1 b during normal combustion. A premature combustion 3 with knocking events can be recognized when a maximum value 3 a of the ionic current signal i which can be allocated to thermal ionization lies over a defined threshold value and/or occurs within a defined period a after the spark end EZ. The threshold value can be formed for example by the highest maximum value 1 b of the ionic current signal occurring under regular combustion after the spark end EZ.
[0046] When extremely premature combustion 4 occurs without knocking, the ionic current signal curve i has a substantially continually dropping progress (without extreme values) after the spark end EZ. A premature combustion without knocking events can thus be recognized in such a way that the ionic current signal i after the spark end EZ decreases continually at least within the chosen measuring window a, without maximum values occurring.
[0047] By recognizing the position of the combustion with ionic current measurement or by recognizing the time difference between the ignition spark and the peak pressure position it is possible to reliably distinguish between normal combustion 1 and premature combustion 3 , 4 .
|
The invention relates to a method for recognizing and avoiding premature combustion events. In order to avoid damage to the engine, the invention provides the following steps:
providing at least one sensor and/or an electronic evaluation circuit for recognizing premature combustion; direct recognition of premature combustion; performing at least one measure for avoiding premature combustion when premature combustion is recognized.
| 5
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method for setting the clamping force exerted by a parking brake.
2. Description of Related Art
Automatic parking brakes (APBs), with which a braking force is continuously exerted in a vehicle while it is stationary, are known. The parking brake is locked, and released again, by way of an actuation element in the vehicle; the actuation generated by the driver results, in a closed- or open-loop control device, in an actuating signal with which control is applied to a braking apparatus, for example an electric motor or a hydraulic pump, to generate braking force at the wheels of the vehicle. Electric motor-based braking apparatuses encompass an electric motor that is disposed on the brake caliper and that acts via a linkage, for example a step-down linkage having a spindle drive, directly on the brake cylinder of the hydraulic brake system. The electric motors are dimensioned so that with them alone, it is possible to set a clamping force with which a vehicle can be held in energyless fashion on 20% slopes. In the case of electric motors of smaller dimensions, or a smaller linkage step-down ratio, the hydraulic braking apparatus is additionally actuated in order to increase the clamping force to the necessary value.
BRIEF SUMMARY OF THE INVENTION
An object of the present invention is to make the requisite clamping force available in a parking brake in reliable and at the same time economical fashion.
The method according to the present invention refers to the setting of a clamping force exerted by a parking brake in a vehicle, such that the parking brake encompasses an electric motor-based braking apparatus and moreover an additional braking apparatus, and a portion of the total clamping force can be generated by each of the two braking apparatuses, the magnitude of the respective portion being modifiably settable between zero and a maximum value. It is thus possible in particular to apply the requisite clamping force exclusively via the electric motor-based braking apparatus, provided it is capable thereof based on its dimensions and the prevailing boundary conditions and ambient conditions. The clamping force portion that is generated via the additional braking apparatus accordingly fluctuates between zero and a maximum value.
With the method according to the present invention, during an actuation phase of the electric motor-based braking apparatus, the motor resistance and the motor constant are determined from the present motor voltage, the present motor current, and the present motor rotation speed; and the clamping force achievable by way of the electric motor-based braking apparatus is ascertained therefrom. The magnitude of the electric motor-based clamping force that can be generated in the instantaneous situation is thus directly identified, which force depends on a variety of parameters or characteristic values or state values, e.g. the temperature in the braking system or in the electric motor-based braking apparatus. Other influencing variables are also sensed directly by way of the magnitude of the maximum attainable electric motor-based clamping force, for example aging in the electric motor. The presently achievable clamping force that is maximally attainable by way of the electric motor-based braking apparatus fluctuates as a result of such influencing variables; the maximum value of the electric motor-based clamping force can be ascertained from the aforesaid measurable or determinable variables.
If it is ascertained that the electric motor-based clamping force alone is not sufficient to establish the requisite target clamping force, the additional braking apparatus is actuated and generates an additional braking force that is superimposed on the electric motor-based clamping force. As a rule, the electric motor-based clamping force and the additional force add to one another; instead of a linear superimposition, a nonlinear superimposition is also a possibility. Because the maximum electric motor-based clamping force can be ascertained with comparatively high accuracy, the additional braking force can also be set with a correspondingly high accuracy in order to attain the target clamping force, so that no, or only a slight, excess of braking force is generated and, correspondingly, only the minimum energy output necessary for the clamping force needs to be generated. Economical operation can thereby be implemented.
Also possible, in addition to this, is an operating mode having an adjustable ratio between electric motor-based braking force and additional braking force, which ratio is oriented not toward the maximum value of the presently attainable electric motor-based braking force but toward other criteria, for example reducing stress on the electric motor. For example, an electric motor-based braking force can be set that is below the maximum settable value, and a correspondingly greater portion can be generated by way of the additional braking apparatus.
The electric additional braking apparatus is in particular a hydraulic braking apparatus, either the hydraulic vehicle brake that has control applied to it by way of actuating signals of a closed- or open-loop control device, or an additionally provided hydraulic braking apparatus. Also possible in principle, however, are other additional braking apparatuses, for example pneumatic or electrically actuable additional braking apparatuses such as electric motors or other electrical actuators.
According to a useful embodiment, provision is made that the achievable electric motor-based clamping force is calculated as a function of the electric motor-based motor torque, which is determined from the present values for motor voltage, motor current, and motor rotation speed, and as a function of the motor resistance and motor constant. The motor constant and motor resistance are in turn determined, based on correlations known per se, from the present values for motor voltage, motor current, and motor rotation speed, which preferably are determined during motor ramp-up directly after the motor is started. The phase during which the motor resistance and motor constant are ascertained refers, for example, to the time period from 5 to 7 tau, 1 tau being the mechanical time constant after which the motor has reached approximately 63% of its final speed. Motor ramp-up is usually almost complete (99.3%) after 5 tau.
If applicable, a shorter consideration time period of, for example, 3 tau is also sufficient, if lower estimation accuracy can be accepted.
It is useful also to incorporate into the determination of the motor torque, which is the basis for calculating the electric motor-based clamping force, the idle torque of the motor; this is ascertained, during an idle phase of the electric motor-based braking apparatus, from the associated idle current. It is moreover useful to take into account, in the context of the electric motor-based clamping force, not only the motor torque but also the linkage step-up ratio with which the motor motion is transferred to the brake calipers of the wheel brakes, as well as the efficiency of the step-down linkage.
Using the method according to the present invention, the current of the electric motor-based braking apparatus can be regulated to an at least approximately constant value, for example in such a way that the attainable electric motor-based clamping force has associated with it a lead current to which regulation occurs, the difference with respect to the target clamping force being generated by way of the additional braking force of the additional braking apparatus. Instead of the lead current, a variable derivable therefrom can also be employed as a lead variable for closed-loop control, for example the lead speed of the electric motor, which speed is inversely proportional to the lead current.
The method preferably executes in a closed- or open-loop control device in which measured variables, in particular electric motor-based measured variables, are processed, and actuating signals for setting the various components of the parking brake are generated therefrom. The closed- or open-loop control device either is a constituent of the parking brake in a vehicle or communicates with the parking brake.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the change over time in various operating variables of a parking brake in the context of a brake application operation.
FIG. 2 schematically depicts the calculation of a reference distance (s ch0 ) to be traveled by the brake piston.
FIG. 3 schematically depicts a motor current control operation.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the change over time in various operating variables of a parking brake in the context of a brake application operation. The application operation can be subdivided substantially into four phases:
At the beginning of a phase 1 , an application request is detected and electric motor 1 installed on the wheel brake is switched on. A switch-on current peak is visible as electric motor 1 is switched on. The current i of electric motor 1 then subsequently drops until, at the end of phase 1 , an idle current is established. The rotation speed ω of electric motor 1 rises in phase 1 , i.e. electric motor 1 is accelerated. At the end of phase 1 , the rotation speed ω of electric motor 1 reaches an idle rotation speed. The voltage u of electric motor likewise rises. At the end of phase 1 an idle voltage is established. As a result of the rotation of a spindle, a nut is moved toward a brake piston of the wheel brake, Because the nut is not yet in contact with the piston base, the clamping force F is equal to zero. The pressure p of hydraulic pump 7 is likewise zero in this phase.
Phase 2 is an idle phase in which an idle current, an idle voltage, and an idle rotation speed are established. The clamping force of the wheel brake continues to be zero in this phase, since the nut is not yet in contact with the piston base. The pressure p of hydraulic pump 7 continues to be equal to zero.
In phase 3 , force buildup occurs. The nut is in contact with the piston base, and the piston is pressed against the brake disk by the rotation of the spindle; the current i of electric motor 1 rises. Because of the load on electric motor 1 , in this phase the voltage u of electric motor 1 drops slightly from the idle voltage level. The rotation speed ω of electric motor 1 likewise drops with increasing clamping force buildup. Shortly before a predetermined target clamping force F m is reached, hydraulic pump 7 is brought on-line and a hydraulic pressure p is thus built up. The target clamping force F m can have, for example, a value that is close to the maximum clamping force of electric motor 1 .
Phase 4 begins when the target clamping force F m is reached. In this phase, both braking systems are active and electric motor 1 is being assisted by hydraulic pump 7 . The total clamping force in this context is made up of a portion from electric motor 1 and a portion from hydraulic pump 7 . In phase 4 , the current i o of electric motor 1 is regulated to a substantially constant value. The hydraulic pressure p rises until a predetermined total clamping force is reached. After that, electric motor 1 and the pump motor of the hydraulic braking apparatus are switched off. As a consequence thereof, the hydraulic pressure p, current i, voltage u, and rotation speed ω of electric motor 1 drop to zero. The total clamping force F ges is maintained in this context.
FIG. 2 schematically depicts the calculation of a reference distance (s ch0 ) to be traveled by the brake piston. The reference distance is the distance that is still to be traveled by the piston, after the target braking force F m is reached, in order to reach a specific total clamping force.
In the exemplifying embodiment depicted, the actual motor torque is estimated from the measured current value i, a rotation speed ω (block 2 ) estimated from the current i, and further motor parameters (block 3 ) such as, for example, a present motor constant k M and a motor resistance R M . If the step-down ratio of the linkage and the efficiencies of the mechanical chain are known, the instantaneous clamping force F est can thus be estimated in step 13 . A suitable iterative algorithm 4 is provided for this purpose. This algorithm 4 additionally calculates, in step 14 , the slope m of the clamping force over the distance s.
As soon as the estimated clamping force has reached the value of the target clamping force F m , the present current value is stored in step 15 , and in step 16 is outputted as a setpoint i 0 for closed-loop current control. When the target clamping force F m is reached in step 16 the present slope m=m 0 and the present clamping force F est =F 0 =F m are also saved. From the slope m and the desired total clamping force F ges , i the reference distance S ch0 that the piston must still travel in order to reach the desired total clamping force is then calculated n steps 17 and 18 . The reference distance S ch0 is obtained in step 18 from a calculation S ch0 =(F ges −F m )/m=F h /m, where F ges is the desired total clamping force, F m the target clamping force of the electromechanical braking apparatus, F h the hydraulically generated additional braking force constituting the difference between the total clamping force F ges and the electromechanical target clamping force F m , and m the slope of the force increase over the distance s traveled by the piston.
FIG. 3 schematically depicts a motor current control operation in which the pump motor of the hydraulic braking apparatus is used as an actuating member. By varying the hydraulic pressure it is possible to relieve the load on electric motor 1 of the parking brake to a greater or lesser extent. The drive torque of electric motor 1 , and thus also the power consumption, can thereby be held to a substantially constant value.
The closed-loop control system encompasses a node 11 at which the system deviation (i 0 −i), or alternatively (ω 0 −ω), is calculated. This difference is delivered to a controller 6 (pump motor control system) that outputs a specific manipulated variable depending on the control algorithm. In the present example, pump motor 7 of the hydraulic pump constitutes the actuating member of the closed-loop control system. The controlled system further encompasses brake caliper 8 and electric motor 1 . A specific current of electric motor 1 is thereby established depending on the degree of hydraulic assistance.
In block 9 , the rotation speed ω of electric motor 1 is also estimated from current i. Using the estimated rotation speed value, the distance s ch traveled by the brake piston can then be calculated (block 10 ). The desired total clamping force is reached when the distance s ch traveled by the brake piston is equal to the reference distance s ch0 . To check this, a difference value Δs between the actual and reference distance is continuously calculated at a further node 12 . As soon as the difference value is equal to zero, electric motor 1 and pump motor 7 are automatically switched off.
The electric motor-based parking brake is preferably hydraulically assisted only in those situations in which it is necessary for proper operation, for example when the slope of the road is greater than a specific value, e.g. 15%, or when a determination is made that the purely electric motor-based clamping force that is made available is not alone sufficient for reasons of voltage or temperature. As long as the driver remains in the vehicle and the slope is, for example, less than 15%, the hydraulic system will preferably not be brought online.
The electric motor-based parking brake could, however, also be designed in such a way that the clamping force is sufficient to hold the vehicle stationary, for example, on slopes of up to 20%. The hydraulic assistance would in this case be brought online only if the slope is, for example, greater than 20%, or if a braking force reserve needs to be provided, for example when the brakes are hot.
A description will be given below of the control application strategy for applying control to the parking brake, which is made up of the electric motor-based braking apparatus and the additional braking apparatus that is preferably embodied hydraulically. The sequence is divided into the four above-described phases of motor startup, the idle phase, force buildup, and the overlay of electric motor-based braking force and additional braking force.
During phase 1 (motor start with motor run-up), the present motor constant k M and the present motor resistance R M are calculated, for example using iterative estimation methods. The calculated motor resistance R M is used to determine the minimum current required to reach the parking clamping force at the present voltage.
During the idle phase (phase 2 ), an idle current I idle is established which is an indication of the idle torque M idle Of the motor. In the force buildup phase (phase 3 )—making use of the motor constant k M and motor resistance R M parameters ascertained in the preceding phases as well as the idle torque M idle of the motor and the present values for current I, voltage U, and rotation speed ω—the actual motor torque M Mot is estimated using a mechanical and electrical motor differential equation:
M Mot =f ( U,I,ω,k M ,R M ,M idle ).
The spring stiffness of the brake caliper is also ascertained in phase 3 , the increase in clamping force being evaluated by comparison with the distance traveled.
If the voltage is insufficient or in the case of a very hot electric motor, a situation may occur in which the required clamping force cannot be made available in exclusively electromechanical fashion. In this case, in phase 3 there is an electromechanical application of a clamping force that is obtained from a modified lead current I Lead or a variable derivable therefrom, for example a lead rotation speed ω Lead of the electric motor. The lead current is defined in this context, independently of the gradient, at a value which is less than the lead current that would theoretically be necessary in order to achieve the required clamping force by way of the electric motor-based braking apparatus; a prefactor that contains measurement inaccuracies and safety margins can additionally be taken into account.
If the lead current I Lead or modified lead current results in an electric motor-based clamping force that is too low to establish the required target clamping force F ges , then in phase 4 (superposition) the additional braking force F h of the additional braking apparatus is overlaid. The present braking force F, which takes into account both the electric motor-based portion and the hydraulic portion, is calculated here from the instantaneous electric motor-based clamping force F est in consideration of the mechanical efficiency, and the additive superposition of the hydraulic clamping force F h in consideration of the hydraulic efficiency. The electric motor-based clamping force F est is calculated as a function of the electric motor-based motor torque M Mot , a linkage step-up ratio i, and the mechanical efficiency η:
F est =f ( M Mot ,i,η ).
The hydraulically provided clamping force F h is calculated from an additional spring distance that is traveled during superposition, and from the spring stiffness of the brake caliper, which is preferably ascertained in phase 3 .
In summary, the hydraulic pressure assistance is carried out not in fixed fashion, but rather dynamically, as a function of the operating conditions of the electric motor-based braking apparatus and the vehicle electrical system. If applicable, phase 4 begins at a point in time at which the rotation speed of the electric motor-based braking apparatus has fallen below a defined limit. This detects, independently of power demand, that the motor is being too severely braked and cannot make available the required torque.
Alternatively, phase 4 begins at a point in time when the electric motor-based clamping force exceeds the product of the motor constant and modified lead current. Also possible is a compensation of the two criteria, in particular such that the beginning of phase 4 occurs at a point in time at which one of the criteria is met.
|
In a method for setting the clamping force exerted by a parking brake, which force is applied by an electric motor-based braking apparatus and, if necessary, by an additional braking apparatus, during an actuation phase of the electric motor-based braking apparatus, the motor resistance and the motor constant are determined from the present motor voltage, the present motor current, and the present motor rotation speed, and the clamping force achievable by the electric motor-based braking apparatus is ascertained therefrom. If the electric motor-based braking force does not reach a required target clamping force, an additional braking force is generated by the additional braking apparatus.
| 1
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a pharmaceutical solid preparation containing a poorly soluble drug for the purpose of improvement of dissolution and a process for the production thereof, and more particularly, to the pharmaceutical solid preparation obtained by delivering and discharging/spraying an aqueous solution and/or a water dispersion of a water soluble polymer as well as a plasticizer solution wherein a poorly soluble drug is dissolved, from nozzle outlets simultaneously and separately, and the process for the production thereof.
[0003] 2. Description of the Invention
[0004] In light of efficiency and safety, it has been regarded as important that significantly high bioavailability is set in the designs for pharmaceutical solid preparations. One of important factors which affect bioavailability of medicines includes solubility of drugs, and numerous studies have been carried out regarding the relationship of solubility and digestive tract absorption. In particular, it has been known that the dissolution behavior of a poorly soluble drug is a key determinant of its oral bioavailability. Various methods have been studied for formulation techniques of solubility improvement in poorly soluble drugs, and among them, a solid dispersion element method has shown promise. This method is defined as a method in which a single molecular drug is dispersed in an inert carrier of a drug in a solid state. Several methods have been proposed for the process of production, and especially, a solvent method and a mixed pulverization method are included as practical methods.
[0005] The solvent method is a method for producing a solid dispersion by dissolving a drug and a water-soluble polymer which is a carrier in a solvent such as an organic solvent, and subsequently distilling off the solvent, or by dissolving the drug in the solvent, dispersing in the carrier followed by distilling off the solvent. It is believed that solubility and bioavailability can be improved because the drug becomes amorphous by dissolving the poorly soluble drug in the solvent and is dispersed in the carrier in such a state.
[0006] As specific examples of the solvent method, Japanese Patent Publication (JP-B) Nos. 3-1288/1991 and 3-28404/1991 have reported that the solid dispersion is obtained as follows. Lactose or the like is granulated with a water-soluble polymer such as hydroxypropylcellulose to make fine particles. Nifedipine which is a poorly soluble drug and a polymer base such as poly(vinylpyrrolidone), hydroxypropylmethylcellulose and methylcellulose are dissolved in the organic solvent to form a solution. The solution was sprayed on the fine particles. The sprayed particles are dried to yield the solid dispersion. Also, in Japanese Patent Provisional Publication (JP-A) No. 281561/2000, the solid dispersion is prepared by dissolving a poorly soluble drug such as cycloheptadines and the water-soluble polymer such as poly(vinylpyrrolidone), hydroxypropylmethylcellulose and hydroxypropylcellulose in a water/alcohol system, and subsequently spraying on lactose followed by granulating.
SUMMARY OF THE INVENTION
[0007] Among conventional methods for producing solid dispersions, those obtained by the solvent method are excellent in terms of solubility and bioavailability of the poorly soluble drug. However, in this solvent method, because organic solvents such as dichloromethane, acetone and alcohol are frequently used, considerable problems have arisen, including problems of organic solvents residue in products, environmental pollution by organic solvents and safety in operation, and corporate problems such as capital investment required to avoid such concerns.
[0008] As a result of an intensive study to solve the above problems, the present inventors have found a method for preparing a pharmaceutical solid preparation without use of an organic solvent which is frequently used in the conventional solvent method. That is, the inventors have found that a pharmaceutical solid preparation which is excellent in dissolution improvement of a drug can be made by being formulated by spraying an aqueous solution and/or water dispersion of a water-soluble polymer as well as a plasticizer solution in which a poorly soluble drug is dissolved from nozzle outlets simultaneously and separately in the pharmaceutical solid preparation. The formulation includes spray granulation and coating treatment of the preparation. For example, granulated materials or coated particles obtained by granulation or coating treatment become pharmaceutical solid preparations which are excellent in dissolution improvement of the drug. According to the present invention, the pharmaceutical solid preparation can be prepared without use of a conventional organic solvent and by using existing equipment and techniques. Also, it was confirmed that the resultant pharmaceutical solid preparation affords a similar improvement effect of dissolution as those of the conventional solvent methods.
[0009] According to the present invention, a solid solution preparation of a poorly soluble drug can be simply prepared using the existing equipment and without use of an organic solvent. Also, preparation of the present invention has the improved dissolution of a poorly soluble drug compared to the solid dispersion obtained by the conventional physically mixed method, and has solubility equivalent to the solid dispersion obtained by the conventional solvent method.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows a cross-sectional drawing of the three fluid nozzle used in a step of fluid bed granulation.
[0011] FIG. 2 shows the changes (average values) of dissolution rate of nifedipine with correlation to time from Examples 1 to 3 and Comparative Examples 1 and 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The poorly soluble drug used in the present invention is a drug of which solubility in water is extremely low and of which absorbability is inferior in normal oral administration, and is referred to, for example, as the drug defined as “nearly insoluble” or “extremely difficult to be dissolved” in Japanese Pharmacopoeia. In Japanese Pharmacopoeia, the solubility of a drug is defined as the degree of dissolvability within 30 minutes when the drug is placed in a solvent and shaken for 30 seconds every 5 minutes at 20±5° C. after making powder in the case of the drug being solid. “Nearly insoluble” is referred to the characteristic where an amount of 10,000 ml or more of the solvent is required to dissolve 1 g or 1 ml of the drug. “Extremely difficult to be dissolved” is referred to the characteristic where a solvent amount of 1,000 to 10,000 ml is required to dissolve 1 g or 1 ml of the drug. Specifically, for example, such drugs include nifedipine, phenacetin, phenytoin, digitoxin, nilvadipine, diazepam, griseofulvin and chloramphenicol.
[0013] Plasticizers used in the present invention include propylene glycol, polyethylene glycol, triethyl citrate, acetyl monoglyceride, glycerine, tributyl citrate, triacetin, diacetin, monoacetin and diethyl phthalate, which may be used alone or in combination of two or more.
[0014] These plasticizers are added aiming at improving the plasticity of polymer films and added for the purpose of improving the uniformity of granulations or coating films. Amounts are not especially limited as long as it is an additional amount required to achieve the purpose. However, it is desirable that the minimum weight part to significantly dissolve the drug in the plasticizer is added ranging from 1 to 20 weight parts, preferably from 7 to 15 weight parts based on one weight parts of the drug used.
[0015] The solution in which the drug used in the present invention is dissolved in the plasticizer is preferably the solution in which the drug and the plasticizer are dissolved at the above weight ratio. However, surfactants, oils, fats or the like can be included for the purpose of further improving the solubility of the drug.
[0016] The water-soluble polymers used in the present invention include, for example, cellulose derivatives such as methylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose acetate succinate, ethylcellulose, hydroxyethylcellulose and sodium carboxymethylcellulose; poly(vinylpyrrolidone); and poly(vinyl alcohol). Among them, hydroxypropylmethylcellulose acetate succinate, hydroxypropylmethylcellulose phthalate, hydroxypropylmethylcellulose and poly(vinylpyrrolidone) are polymers effective for dissolution of the drug. Also, a mixture of these water-soluble polymers can be used as appropriate.
[0017] The fineness of these water-soluble polymers is not especially limited as long as it does not block up a spray gun when used as a dispersion, and the average particle diameter may be 100 μm or less, and preferably 50 μm or less.
[0018] The aqueous solutions of the water-soluble polymers include the aqueous solution obtained by dissolving in a weak alkali aqueous solution such as an ammonia solution. It is desirable that the solution is prepared at 5 to 30% by weight. In the dispersion of the water-soluble polymer, said polymer can be dispersed in a given amount of water with stirring, and the concentration is not especially limited but a concentration at 5 to 30% by weight may be preferred.
[0019] The combination ratio of the poorly soluble drug to the water-soluble polymer in the pharmaceutical solid preparation of the present invention is appropriately determined depending on the types of the poorly soluble drug and water-soluble polymer. It may be from (1:0.1) to (1:10), and preferably from (1:0.5) to (1:5) as a weight ratio. When the combination ratio of the water-soluble polymer is lower, recrystallization of the drug may be precipitated in the pharmaceutical solid preparation resulting in lowering the dissolution. When it is higher, it may not be preferable because dissolution may not be significantly improved and the pharmaceutical solid preparation may be bulky leading to increased dosages.
[0020] Formulation of the present invention includes coating treatment and spray granulation of the preparation. The types of preparations subjected to coating are not especially limited, but solid preparation such as tablets, granules or capsules may be preferable for performing uniform coating. Those subjected to spray granulation include powder bodies and nuclei of lactose, sucrose, glucose, trehalose, fructose, dextrin, starch, pullulan, carboxymethylcellulose and salts thereof, carboxymethylstarch and salts thereof, cellulose, poly(vinylalcohol) and hemicellulose.
[0021] The amount of coating varies depending on the types of solid preparation. An amount of 3 to 50% by weight as the solid content may be preferable based on the weight of the solid preparation. In the case of coating the solid preparation, coating of the solid preparation may be carried out using another coating agent such as hydroxypropylmethylcellulose prior thereto.
[0022] The process for producing the solid dispersion preparation of the present invention can advantageously produce the pharmaceutical solid preparation when, for example, the spray gun shown in FIG. 1 is used.
[0023] This has a construction such that the water-soluble polymer dispersion and/or the water-soluble polymer solution and the plasticizer solution are appropriately selected and inserted via a pump through a liquid A inlet 1 and a liquid B inlet 2 , respectively. The liquid A inlet 1 and liquid B inlet 2 are linked to a nozzle outlet of A nozzle 4 and a nozzle outlet of B nozzle 5 , respectively, and liquid A and B are discharged/sprayed. Air from an air inlet 3 is discharged through a nozzle outlet of an air nozzle (cap) 6 . In FIG. 1 , the nozzle outlets of A nozzle 4 , B nozzle 5 and air are in approximately concentric circles and arranged from the inside to the outside. FIG. 1 also shows an O ring 7 and a gasket 8 . There may be an embodiment where the water-soluble polymer dispersion and/or water-soluble polymer solution is used as liquid A and the plasticizer solution is used as liquid B. Conversely, there may be also an embodiment in which the plasticizer solution is used as liquid A and the water-soluble polymer dispersion and/or water-soluble polymer solution is used as liquid B.
[0024] The pump to insert the water-soluble polymer dispersion and/or water-soluble polymer solution and the plasticizer solution is not especially limited, and a commonly available one is used. It may be preferable to use a gear pump or a tube pump.
[0025] Materials of the spray gun used in the present invention are not especially limited as long as they are water-proof and are not dissolved and melted in the plasticizer at a temperature from room temperature to around 100° C. Heat-resistant materials such as stainless steel, which resists rust, and silicone may be preferable.
[0026] The shape and diameter of the nozzle are not especially limited as long as they are capable of spraying. A diameter for ease in spraying or a distance of 0.1 to 5 mm between the tube walls may be preferred.
[0027] The rate of the delivered solution from the spray gun is not especially limited, but the rate of a few g/min to some 100 g/min may be preferred as a rough standard to be easily formulated in general. There may be no concerns even in the case of a construction where air or gas for spraying can be supplied to the nozzle. The supplied amount of air or gas is not especially limited as long as it is in a range capable of spraying, but the amount of some 10 liters/min to some 100 liters/min may be preferable. Types of gas other than air are not especially limited, but a inert gas such as nitrogen or helium which is less interactive with the drug may be preferable.
[0028] By using this spray gun, common formulation machines equipped with the system to spray/dry the liquid may be used as such.
[0029] Fluid bed granulation equipment, pan coating equipment, coating equipment incorporated with a ventilation dry system, and fluid coating equipment can be used as equipment for formulation.
[0030] In order to further make the prepared solid preparation into tablets, those usually used thereafter in the field of preparations, other than the poorly soluble drug and water-soluble polymer, for example, an excipient such as lactose, corn starch, crystalline cellulose, D-mannitol and erythritol; a disintegrant such as low substituted hydroxypropyl cellulose, cross carmellose sodium, carmellose calcium and cross povidone; a pigment; perfume; a sweetener; may appropriately be added to the pharmaceutical solid preparation of the present invention if necessary.
[0031] Examples and Comparative Examples are shown below, and the present invention is described in detail, but the invention is not limited thereto.
EXAMPLE 1
[0032] The poorly soluble drug, nifedipine (10 g)(supplied by Daito Co., Ltd.) was dissolved in a mixture solution of the plasticizer, polyethylene glycol 400 (96 g) and triethyl citrate (4 g) to make Spray A solution. As the water-soluble polymer solution, a dispersion made of 6 g of talc, 0.2 g of sodium lauryl sulfate and 107.1 g of purified water for 20 g of hydroxypropylmethylcellulose acetate succinate (HPMCAS)(AS-MF: supplied by Shin-Etsu Chemical Co. Ltd.) was prepared to make Spray B solution. Lactose (200 g) (lactose 200M: supplied by DMV Co., Ltd.) was fluidized in a fluidized-bed granulation machine (equipment name: Multiplex: supplied by Freund Industrial Co., Ltd.: Multiplex MP-01), and both Spray A and B solutions were sprayed to granulate in a manner of side spraying using three fluid nozzles (spray gun) shown in FIG. 1 . Spray A solution, Spray B solution and compressed air were supplied to three fluid nozzles by a tube pump from the outside. Solutions A and B and compressed air were passed through the solution lead-in path A and B nozzles and the air lead-in path (cap), respectively, and were sprayed as spray solutions which spread over concentric circles.
[0033] After granulation, the granules were selected by a 14-mesh sieve to yield preparation containing nifedipine.
[0034] The manipulation condition was as follows.
[0035] Spray gun: identical to the spray gun shown in FIG. 1 . One having an internal diameter of 2.5 mm as A nozzle and one having an external diameter of 2.0 mm and the internal diameter of 1.0 mm as B nozzle were used.
[0036] Temperature of Spray A and B solutions: 27° C.
[0037] Dry air temperature: 70 to 80° C.
[0038] Rate of supplying air to the spray gun: 2.5 liters/min
[0039] Rate of supplying Spray A solution: 5 g/min
[0040] Rate of supplying Spray B solution: 4.1 g/min
[0041] Manipulation: 40 minutes
[0042] Used amount of HPMCAS: 2 fold by weight based on major component (nifedipine)
EXAMPLE 2
[0043] Granulation was carried out to obtain the nifedipine containing preparation in the same manner as that in Example 1, except that the aqueous solution of the water-soluble polymer was made by dissolving 20 g of hydroxypropylmethylcellulose (TC-5R: supplied by Shin-Etsu Chemical Co. Ltd.) in 180 g of purified water to render Spray B solution.
EXAMPLE 3
[0044] Granulation was carried out to obtain the nifedipine containing preparation in the same manner as that in Example 1, except that 200 g of lactose in Example 1 were replaced with the mixed powder of 170 g of lactose and 30 g of Hydrated Silicon-Dioxide (Carplex #80: supplied by Shionogi & Co. Ltd.).
COMPARATIVE EXAMPLE 1
[0045] 10 g of Nifedipine and 20 g of hydroxypropylmethylcellulose acetate succinate were dissolved in 300 g of mixed solvents of dichloromethane and ethanol (weight ratio 1:1) to render a spray solution. Lactose (200 g) was fluidized in a fluid bed granulation machine, and the spray solution was sprayed to granulate in the manner of side spraying followed by being selected by a 14-mesh sieve to yield a preparation containing nifedipine.
COMPARATIVE EXAMPLE 2
[0046] 10 g of Nifedipine, 20 g of hydroxypropylmethylcellulose acetate succinate and 200 g of lactose were mixed in a mortar to yield the nifedipine containing preparation physically mixed and powdered.
TEST EXAMPLE
[0047] The following test was carried out for the preparations of Examples 1 to 3 and Comparative Examples 1 and 2.
[0048] (1) Samples: preparations of Examples 1 to 3 and Comparative Examples 1 and 2.
[0049] (2) Test method: as the test solution, 500 ml of the second solution (pH 6.8) described in Japanese Pharmacopoeia was used. Each sample corresponding to 10 mg of nifedipine was added thereto, and a test was carried out according to the second method of the dissolution test method (paddle method) of Japanese Pharmacopoeia. The rotational frequency of the paddle was 100 rpm. For each constant time elapsed (0, 10, 20, 40, 80 minutes), 2 ml of solution was collected, to which a second solution was added up to a total volume of 10 ml to dilute 5 times. Subsequently, the dissolution amount of nifedipine was determined by measuring an absorbance at wavelengths of 325 nm and 500 nm using an automatic dissolution tester (Shimadzu UV-160: supplied by Shimadzu Corporation).
[0050] For an evaluation of dissolution rate improvements, those which provided a supersaturated solubility which exceeds the saturated solubility of nifedipine (10 mg/ml) and showed an dissolution rate of 75% or more of the drug in preparation in the results of the above dissolution test were considered “good”.
[0051] (3) Results of the test: changes of dissolution rate of nifedipine with correlation to the time elapsed (mean values of three points) are shown in FIG. 2 .
[0052] As is obviously shown in FIG. 2 , the preparation according to the present invention can provide a supersaturated solution which exceeds the saturated solubility of nifedipine (Comparative Example 2), and maintain the supersaturated concentration without a decrease with correlation to the time elapsed. Also it has been shown that preparation of the present invention has a drug solubility improvement effect comparative to that of the preparation (Comparative Example 1) by the solvent method using an organic solvent of which the effect has been confirmed.
|
Among the conventional processes for producing solid dispersion, the solid dispersion obtained by a solvent method is excellent in terms of solubility and bioavailability of a poorly soluble drug. However, due to frequent uses of organic solvents in the solvent method, problems have arisen such as organic solvent residue in products, environmental pollution and operational safety as well as corporate problems such as capital investment and the like required to avoid such events. The present invention provides a process for preparing pharmaceutical solid preparations without use of organic solvents frequently used in conventional solvent methods. Specifically, the present invention provides a process for producing a pharmaceutical solid preparation, which is formulated by spraying a solution wherein a poorly soluble drug is dissolved in a plasticizer, and an aqueous solution and/or water dispersion of a water-soluble polymer from nozzle outlets simultaneously and separately in the process for producing the pharmaceutical solid preparation.
| 0
|
FIELD OF THE INVENTION
[0001] The present invention relates to a process for preparation of optically pure or optically enriched enantiomers of sulphoxide compounds, such as omeprazole and structurally related compounds, as well as their salts and hydrates.
BACKGROUND OF THE INVENTION
[0002] Substituted 2-(2-pyridinylmethylsulphinyl)-1H-benzimidazoles of formula (I) are useful
[0000]
[0000] as inhibitors of gastric acid secretion.
wherein R 1 , R 2 and R 3 are the same or different and selected from hydrogen, alkyl, alkylthio, alkoxy optionally substituted by fluorine, alkoxyalkoxy, dialkylamino, and halogen; R 4 -R 7 are the same or different and selected from hydrogen, alkyl, alkoxy, halogen, halo-alkoxy, alkylcarbonyl, alkoxycarbonyl, and trifluoroalkyl.
[0003] For example, the compounds with generic names omeprazole, lansoprazole, rabeprazole, pantoprazole are used in the treatment of peptic ulcer. These compounds have a chiral center at the sulphur atom and thus exist as two optical isomers, i.e. enantiomers.
[0004] It has been well recognized in several pharmacologically active compounds that one of the enantiomer has superior biological property compared to the racemate and the other isomer.
[0005] For example, omeprazole (CAS Registry No. 73590-58-6), chemically known as 5-methoxy-2-{[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulphinyl}-1H-benzimidazole, is a highly potent inhibitor of gastric acid secretion. It has a chiral center at the sulphur atom and exists as two enantiomers (S)-(−)-omeprazole and (R)-(+)-omeprazole. It has been shown that the (S)-enantiomer of omeprazole has better pharmacokinetic and metabolic properties compared to omeprazole. The (S)-enantiomer of omeprazole having generic name esomeprazole is marketed by Astra Zeneca in the form of magnesium salt under the brand name NEXIUM®. Therefore, there is a demand and need for an industrial scale process for manufacturing esomeprazole.
[0006] The methods of synthesis of racemic sulphoxide compounds of formula (I) are very successful for a large-scale industrial manufacture. However, the production of optically pure sulphoxide compounds of formula (I) is not easy.
[0007] The prior art methodologies for the preparation of single enantiomers of sulphoxides of formula (I) are based on enantioselective or chiral synthesis, optical resolution of the racemate, separation by converting the racemate to diastereomers, or by chromatography.
[0008] For example, some of the earliest prior art on enantioselective synthesis of the single enantiomers of sulphoxides of formula (I) described in Euro. J. Biochem. 166, (1987), 453, employed asymmetric sulphide oxidation process developed and reported by Kagan and co-workers in J. Am. Chem. Soc. 106 (1984), 8188. The process disclosed therein provides sulphoxide products in an enantiomeric excess of only about 30%, which upon several recrystallization steps yielded optically pure sulphoxide upto an e.e. of 95%. The oxidation was performed by using tert-butyl hydroperoxide as oxidizing agent in the presence of one equivalent of a chiral complex obtained from Ti(OiPr) 4 /(+) or (−)-diethyl tartrate/water in the molar ratio of 1:2:1. A minimum of 0.5 equivalent of titanium reagent was found to be a must for obtaining very high enantioselectivity.
[0009] An improvement in the above oxidation process to obtain higher enantioselectivity was reported by Kagan and co-workers in Tetrahedron (1987), 43, 5135; wherein tert-butyl hydroperoxide was replaced by cumene hydroperoxide. In their further study reported in Synlett (1990), 643; Kagan and co-workers found that high enantioselectivity can be obtained if the temperature is maintained between −20° C. to −40° C., and methylene chloride is used as a solvent.
[0010] In contrary to Kagan's observation of requirement of low temperature and chlorinated solvent like methylene chloride for high enantioselectivity of the chiral oxidation, Larsson et al in U.S. Pat. No. 5,948,789 (equivalent to PCT publication WO 96/02535) have described an enantioselective process for the synthesis of the single enantiomers of compound of formula (I) by the chiral oxidation of the pro-chiral sulphide of formula (Ia) utilizing a chiral titanium (IV) isopropoxide complex in solvent systems such as toluene, ethyl acetate at 20-40° C., and most importantly a base like amine such as triethyl amine or diisopropyl amine.
[0000]
[0011] Although the formation of % e.e. of the desired isomer is satisfactory, the method suffers from the disadvantage (a) of low chemical conversion; (b) formation of undesired sulphide and sulfone impurities in substantial amounts, necessitating further purification by one or more tedious crystallization.
[0012] It is obvious from the above that such conversions which result in low chemical conversion and require costly metal complex and protracted purification, surely, is not desirable process for making a product such as optically active prazole in an industrial scale.
[0013] WO 96/17076 teaches a method of enantioselective biooxidation of the sulphide compound (Ia), which is effected by the action of Penicillium frequentans, Brevibacterium paraffinolyticum or Mycobacterium sp.
[0014] WO 96/1707 teaches the bioreduction of the racemic omeprazole to an enantiomer or enantiomerically enriched sulphide of formula (Ia), which is effected by the action of Proteus vulgaris, Proteus mirabilis, Escherichia coli, Rhodobacter capsulatus or a DMSO reductase isolated from R. capsulatus.
[0015] The separation of enantiomers of omeprazole in analytical scale is described in Marie et al.; J. Chromatography, 532, (1990), 305-19. WO 03/051867 describes a method for preparation of an enantiomerically pure or optically enriched enantiomer of either omeprazole, pantoprazole, lansoprazole, or raberpazole from a mixture containing the same using means for simulated moving bed chromatography with a chiral stationary phase such as amylose tris(S)-methylbenzycarbanmate. However, chromatographic methods are not suitable for large-scale manufacture of these prazoles.
[0016] The optical resolution methods taught in the art for separating the enantiomers of certain 2-(2-pyridinylmethylsulphinyl)-1H-benzimidazoles of formula (I) utilizes the diastereomer method, the crystallization method or the enzyme method.
[0017] The resolution process disclosed in DE 4035455 and WO 94/27988 involve converting the racemate 2-(2-pyridinylmethylsulphinyl)-1H-benzimidazoles to a diastereomeric mixture using a chiral acyl group, such as mandeloyl, and the diastereomers are separated and the separated diastereomer is converted to the optically pure sulphoxide by hydrolysis.
[0018] The method suffers from the following disadvantages,
(i) the resolution process involves additional steps of separation of diastereomeric mixture, and hydrolysis of the N-substituent in separated diastereomer, (ii) the conversion of the racemate to diastereomeric acyl derivative is low yielding (˜40%), (iii) the diastereomer from the unwanted (R)-enantiomer is separated and discarded,
WO 2004/002982 teaches a method for preparation of optically pure or optically enriched isomers of omeprazole by reacting the mixture of optical isomers with a chelating agent (D)-diethyl tartrate and transition metal complex titanium (IV) isopropoxide to form a titanium metal complex in an organic solvent such as acetone in presence of a base such as triethyl amine, which is then converted to salt of L-mandelic acid. The mandelic acid salt of the titanium complex of optical isomer derived from (S)-enantiomer of omeprazole gets precipitated, which is separated and purified to obtain chiral purity of about 99.8%.
[0022] Optically active 1,1′-bi-2-naphthol (BINOL) and its derivatives are useful as chiral ligands in catalysts for asymmetric reactions to hosts for molecular recognition and enantiomer separation, and often intermediates for the synthesis of chiral molecules.
[0023] BINOL is known to form crystalline complexes with a variety of organic molecules through hydrogen bonding. The (S) and/or (R) BINOL was found to be useful as a chiral host for enantioselective complexation. The application of BINOL in resolution of omeprazole is disclosed Deng et al in CN 1223262.
[0024] The Chinese patent application CN 1223262 (Deng et al) teaches the utility of chiral host compounds such as dinaphthalenephenols (BINOL), diphenanthrenols or tartaric acid derivatives in the resolution of prazoles. The method consists of formation of 1:1 solid complex between the chiral host and one of the enantiomer of the prazole, the guest molecule. The other enantiomer remains in the solution. The racemic prazole is treated with the chiral host in a mixture of solvent comprising of aromatic hydrocarbon solvents such as benzene, alkyl substituted benzene or acetonitrile and, hexane. The solid complex is separated from the solution, and dissolved again in afresh solvent system by heating to 60-130° C. and then keeping at −20-10° C. for 6-36 hrs to obtain higher e.e. value for the solid complex. The process is repeated many times to obtain high e.e. values for the solid complex. The host and the guest in the solid complex are separated by column chromatography. The final separated single enantiomer of the prazole is then recrystallized from a mixture of methylene chloride or chloroform and, ether.
[0025] In a later publication in Tetrahedron Asymmetry 11 (2000), 1729-1732 the inventors of the above mentioned Chinese patent application reported the resolution of omeprazole using (S)-BINOL. An inclusion complex of (S)-BINOL and (S)-omeprazole was obtained as a grey-blue complex with 90.3% e.e. by mixing racemate omeprazole and (S)-(−)-BINOL in the mole ratio 1:1.5, in a solvent mixture of benzene:hexane (v/v=4:1) at 110° C. The inclusion complex obtained was further purified by recrystallization in benzene:hexane (v/v, 1:1) and separated on a silica gel column to yield (S)-(−)-omeprazole with 98.9% e.e. and 84.1% overall yield. The (S)-(−)-omeprazole so obtained was recrystallized in water to obtain as a white powder with 99.2% e.e.
[0026] In this publication, the authors have reported their observation of criticality of the benzene:hexane solvent ratio in obtaining the inclusion complex and the enantioselectivity. The authors reportedly have obtained the best enantioselectivity of 90.3% e.e. when the solvent ratio of benzene:hexane is 4:1 and the mole ratio of racemate omeprazole and (S)-(−)-BINOL is 1:1.5.
[0027] Further, by comparing the IR stretching frequencies observed for S═O bond in racemate omeprazole (1018 cm −1 ) and its inclusion complex with (S)-(−)-BINOL (1028 cm −1 ), the authors have concluded that the S═O bond which involved in a N—H . . . O═S hydrogen bond does not attribute the formation of hydrogen bonding in the inclusion complex, and the chiral recognition in the inclusion complex may occur via formation of hydrogen-bonded supramolecular chiron.
[0028] The method described in the above-mentioned Chinese patent application suffers in that,
(i) due to very low e.e. value for the solid complex obtained for the first time, the complexation process has to be repeated till the desired e.e. value is obtained, (ii) to separate the host and the guest, one has to take recourse to tedious chromatographic methods, (iii) overall the resolution involves several operations of complex formation, separation, purification by chromatography and recrystallization, (iv) For the purpose of chromatography the amount silica and the solvent required is exorbitant (v) with more operation steps, there is considerable material loss leading to lowering of the overall yield, which is not satisfactory for a commercial scale production, (vi) the use of hexane with low flash point is not recommended for industrial processes, (vii) volumes of the solvents to be handled having low flash point are quite large, necessitating special design of plant and machinery for safety, (viii) benzene is carcinogenic and is listed as a class 1 solvent in ICH guideline.
[0037] Taking these considerations, the process disclosed in the CN 1223262 (Deng et al) does not give cost effective and eco-friendly method of manufacture.
[0038] It is evident from the above that there is a need for synthesizing optically pure sulphoxide compounds of formula (I), their salts, and their hydrates by a process that is (a) cost effective (b) simple (c) easy to operate (d) eco-friendly, (e) consistently give good yields and purity with minimum variables (e) highly reproducible.
[0039] The present invention provides such a solution.
OBJECT OF THE INVENTION
[0040] The object of the invention is to provide an improved method for the manufacture of single enantiomers of the sulphoxide compounds of the formula (I) and their pharmaceutically acceptable salts and hydrates, thereby resulting in significant economic and technological improvement over the prior art methods.
[0041] More specifically, the object of the invention is to manufacture single enantiomers of Omeprazole, Rabeprazole, Lansoprazole or Pantoprazole covered by the formula (I), and pharmaceutically acceptable salts and hydrates.
SUMMARY OF THE INVENTION
[0042] Thus, according to one aspect of present invention there is provided a process for preparation of an optically pure or optically enriched enantiomer of a sulphoxide compound of formula (I), said process comprises:
a) providing, a mixture of optical isomers of the sulphoxide compound of formula (I) as starting material, in an organic solvent; the different optical isomers having R and S configurations at the sulfur atom of the sulphoxide group; b) reacting the mixture of optical isomers, in the organic solvent, with a chiral host; c) separating the adduct formed by the enantiomer and the chiral host; d) if desired, repeating the operation of step (b); e) treating the adduct obtained in step (c) or (d) with a metal base selected from Group I or Group II metal, thereby obtaining the metal salt of the enantiomer of the sulphoxide compound in a substantially optically pure or optically enriched form; f) optionally, converting the Group I metal salt of substantially optically pure or optically enriched enantiomer of the sulphoxide compound obtained in step (e) to magnesium salt.
DETAILED DESCRIPTION OF THE INVENTION
[0049] The invention is directed to a process for preparation of an optically pure or optically enriched enantiomer of a sulphoxide compound of formula (I). Intermediates in the processes of this invention are also part of this invention, as are their salts and hydrates. The sulphoxide compounds suitable as substrates for the process of this aspect of the invention include, for example, omeprazole, lansoprazole, pantoprazole, rabeprazole In a preferred embodiment in step (b), the chiral host is optically pure or optically enriched (S)-(−)-BINOL or (R)-(+)-BINOL.
[0050] In a more preferred embodiment, the invention provides a specific process for preparing a substantially optically pure or optically enriched form of omeprazole and its pharmaceutically acceptable salts. In other preferred aspect, the invention also provides an amorphous form of magnesium salt of esomeprazole trihydrate.
[0051] The process is depicted in the following Scheme 1
[0000]
[0052] In their endeavor to obtain optically pure enantiomer of the sulphoxide compounds of the formula (I), for example the (S)-omeprazole from racemate omeprazole or optically enriched omeprazole by resolution method using BINOL, the present inventors surprisingly found that,
(i) use of mixture of toluene and cyclohexane significantly improved the e.e. value of the inclusion complex of (S)-BINOL and (S)-omeprazole, (ii) the inclusion complex of (S)-BINOL and (S)-omeprazole can be directly converted to Group I or Group II metal salt of (S)-omeprazole without any further purification of the complex by recrystallization and separation of the host and the guest by chromatography, (iii) the (S)-BINOL and the other isomer (R)-omeprazole could be recovered and recycled, (iv) the methodology could be conveniently adopted for other sulphoxide compounds such as Rabeprazole, Lansoprazole, or Pantoprazole,
[0057] The present method addresses the drawbacks of the resolution using chiral host disclosed in the CN 1223262 by,
(i) providing the chiral complex in very high e.e. in minimum number of operational steps, (ii) obviates the usage of hexane which is having low flash point, (iii) utilizes cyclohexane which is a preferred solvent over hexane as the allowed limit of residual solvent for cyclohexane is 3880 ppm, while it is 290 ppm for hexane, in the ICH guideline, (iv) significantly increases the overall yield through recovering of the chiral material and racemization of the undesired isomer,
[0062] In one embodiment of the process aspect of the invention, the starting material is a compound of the formula (I). In one variant, R 1 , R 2 are methyl; R 2 and R 5 are methoxy; and R 4 , R 6 , and R 7 are hydrogen. In another variant R 4 , R 5 , R 6 , and R 7 are hydrogen; R 1 is hydrogen; R 3 is methyl, and R 2 may be —O(CH 2 ) 3 OCH 3 or —OCH 2 CF 3 . In a further variant, R 1 , R 4 , R 6 and R 7 are hydrogen; R 5 is difluoromethoxy; and R 2 and R 3 are methoxy. Specific starting materials that are suitable include omeprazole, lansoprazole, rabeprazole, and pantoprazole.
[0000]
[0063] Initially, a solution of the racemic mixture of the sulphoxide compound of formula (I) is provided in an organic solvent, by suspending or dissolving the compound of formula (I). As used herein, the term “solvent” may be used to refer to a single compound or a mixture of compounds. Suitable organic solvents are preferably alkyl benzenes and cyclohexane. Among the alkyl benzenes, toluene and xylene are preferred. Preferably, the organic solvent is at least a mixture of alkyl benzene such as toluene or xylene and cyclohexane. More preferably, the organic solvent is a mixture of toluene and
[0000]
[0000] cyclohexane.
[0064] Suitable chiral host include 1,1′-bi-2-naphthol (BINOL), diphenanthrenols or tartaric acid derivatives. Preferably, the (S)-(−)-BINOL or (R)-(+)-BINOL are used. The (S)-(−)-BINOL or (R)-(+)-BINOL may be used in optically pure or optically enriched form.
[0065] By mixing the chiral host with the racemate sulphoxide of formula (I) (guest molecules) in the solvent and gently warming to about 50-55° C., the chiral host forms an adduct with one of the enantiomer by a chiral recognition or molecular recognition process. The adduct known as a host-guest inclusion complex is formed via selectively and reversibly including the chiral guest molecules in host lattice through non-covalent interactions such as hydrogen bonding.
[0066] The host-guest inclusion complex crystallizes out as solid compound upon lowering the temperature, from ambient to about 0-10° C. The complex was separated out, washed with the solvent. If desired, the separated host-guest inclusion complex may be re-dissolved in the solvent and crystallized out.
[0067] By these operations, the process achieves the physical separation of the two enantiomers of the sulphoxide compound of formula (I), one enantiomer in the form of a host-guest inclusion complex and the other enantiomer remains in the solution.
[0068] If only one enantiomer is desired, the other may be racemized, in any way known to those skilled in the art, to obtain the starting material sulphoxide of formula (I). The racemization permits increased utilization of the material since the racemized product may be re-used in the process as described.
[0069] The adduct is treated with a metal base (MB) where M is the metal of Group I or Group II in an alcoholic solvent selected from methanol, ethanol, isopropanol, and tent-butyl alcohol or mixtures thereof to obtain the corresponding metal salt of optically pure optically enriched enantiomer of the sulphoxide compound of formula (I).
[0070] In one embodiment, the adduct is treated with a metal base of Group I metal to obtain an alkali metal salt of optically pure optically enriched enantiomer of the sulphoxide compound of formula (I). The alkali metal salt is then converted to the magnesium salt.
[0071] The preferred metal base of Group I metal are potassium hydroxide or sodium hydroxide.
[0072] In another embodiment, the adduct is directly converted to the magnesium salt of optically pure optically enriched enantiomer of the sulphoxide compound of formula (I), for instance, by treating with magnesium in methanol.
[0073] In a further embodiment, the adduct is first converted to an alkaline earth metal salt such as barium or calcium by treating with their oxide or hydroxide in an alcoholic solvent, and subsequently converted to the magnesium salt.
[0074] The preferred embodiment of the process aspect of the invention involves preparation of the (S) enantiomer of omeprazole, known as esomeprazole, and its salts. The scheme 2 illustrates the preferred process contemplated by the inventors.
[0075] Racemic omeprazole, was treated with the chiral host (S)-(−)-BINOL, in toluene-cyclohexane (4:1 v/v). A bluish gray adduct, the inclusion complex was formed between the (S)-BINOL and (S)-isomer of omeprazole, which was separated by filtration and washed with a mixture of cyclohexane and toluene. The optical purity of esomeprazole in the complex as measured by HPLC was not less than 99.5% e.e.
[0076] The IR-spectra of racemic omeprazole, (S)-BINOL and the host-guest inclusion complex is provided in FIGS. 1 , 2 , and 3 respectively. There is no significant difference in the stretching frequency of S═O bond in racemate omeprazole (1017 cm −1 ) as compared to the stretching frequency of 1028 cm −1 in the inclusion complex.
[0077] The adduct isolated is treated with potassium hydroxide or sodium hydroxide in an alcoholic solvent selected from methanol, ethanol, isopropanol, and tent-butyl alcohol or mixtures thereof to obtain the potassium or sodium metal salt of optically pure optically enriched enantiomer of the sulphoxide compound of formula (I).
[0078] The sodium or potassium salt of optically pure optically enriched enantiomer of the sulphoxide compound of formula (I) is converted to magnesium salt by treating with MgSO 4 .
[0079] In another embodiment the (S)-omeprazole-(S)-(−)-BINOL adduct is converted directly to its magnesium salt by treating with magnesium in methanol as depicted in Scheme 2.
[0080] The esomeprazole magnesium obtained by the process is in an amorphous form characterized by powder X-ray diffraction pattern given in FIG. 5 .
[0000]
[0081] Alternatively, if (R)-enantiomer of omeprazoele is desired, (R)-(+)-BINOL may be used in the process described above.
[0082] The following examples illustrate the practice of the invention without being limiting any way.
Example 1
Preparation of (S)-omeprazole-(S)-(−)-BINOL complex
[0083] Omeprazole (100 g, 0.2898 mole) was added to a mixture of toluene (1600 ml) and cyclohexane (400 ml) in a round bottom flask kept at 25-30° C. (S)-(−)-BINOL (124.3 g, 0.4346 mole) was added and the content warmed to about 50-55° C. with stirring for 30-45 minutes. The content of the flask was allowed to attain the ambient temperature and then cooled to 0-5° C. with stirring for about an hour. The (S)-omeprazole-(S)-(−)-BINOL complex crystallizes out, filtered and washed with a mixture of cyclohexane/toluene (1:4, v/v) pre-cooled to 0-5° C. The (S)-omeprazole-(S)-(−)-BINOL complex was dried at 35-40° C. under reduced pressure. The e.e. of (S)-omeprazole in the complex was found to be 99.5%. Yield: 85%.
[0084] The IR spectrum of the complex is given in FIG. 3 . The powder X-ray diffraction pattern is given in FIG. 4
Example 2
Preparation of Esompeprazole Potassium Salt
[0085] To a solution of potassium hydroxide (31 g, 0.5535 mole) in methanol (500 ml) kept in a round bottom flask was added (S)-omeprazole-(S)-(−)-BINOL complex (100 g, 0.1584 mole) with stirring at 25-30° C. The content of the flask were stirred for about 2-2.5 hrs at 25-30° C. and then cooled to 0-5° C. and stirred for a further period of about 1-1.5 hrs. The potassium salt of esomeprazole was filtered, washed with cold methanol (50 ml), followed by washing with cold acetone (100 ml) and dried under suction. The optical purity of esompeprazole potassium as tested by HPLC was not less than 99.5%. Yield: 80%.
Example 3
Preparation of Esomeprazole Magnesium Salt
[0086] To a solution of esomeprazole potassium salt (100 g, 0.261 mole) in methanol (500 ml) kept in a round bottom flask, was added magnesium sulphate heptahydrate (64.1 g, 0.26 mole) at 25-30° C. and stirred for 1.5-2 hrs. The insoluble material formed was filtered off and the filtrate was passed through a 0.45 micron membrane filter. To the filtrate, water (1300 ml) was added and stirred at 25-30° C. for 1-1.5 hrs, cooled to 0-5° C., and stirred for a further period of 1-1.5 hrs. The solid formed was collected by filtration and washed with water and dried under reduced pressure at 40-45° C. to obtain the esomeprazole magnesium salt.
Yield: 45%.
[0087] Optical purity: 100%
Optical rotation: [α] D =−142.04° at 25° C. and c=0.5% in methanol
e.e.: 100%
[0088] The esomeprazole magnesium salt obtained is in an amorphous form as characterized by its powder X-ray diffraction pattern given in FIG. 5 .
[0089] The moisture content of the product is 7.5% by TGA, indicating that the product is a trihydrate.
Example 4
Preparation of Esomeprazole Magnesium Salt
[0090] To a suspension of Magnesium turnings (0.5 g, 0.0208 mole) in methanol (15 ml) was added methylene chloride (0.5 ml), stirred for about 1.5-2 hrs at 55-60° C. (S)-omeprazole-(S)-(−)-BINOL complex (2 g, 0.0030 moles) was added and stirred for 45-60 minutes. The insoluble salts were filtered off. To the combined filtrate was added water (30 ml), stirred for about 45-60 minutes and cooled to 0-5° C. to obtain a solid, which was collected by filtration and dried.
Yield: 35.4%
[0091] e.e.: 99.6%
optical purity: 99.8%
Example 5
Preparation of (S)-rabeprazole-(S)-(−)-BINOL complex
[0092] To a mixture of toluene (100 ml) and cyclohexane (150 ml) in a round bottom flask was added rabeprazole (10 g, 0.0278 mole), and gently warmed to 48-52° C. for 30-45 minutes. The reaction mass was cooled to 25-30° C. and further cooled to 3-8° C., stirred for 45-60 minutes to isolate a solid product, which was washed with cold cyclohexane-toluene (1:1 v/v). The product was dried at 35-40° C. under reduced pressure.
Yield: 55.6%
[0093] e.e.: 99.8%
optical purity: 99.9%
|
A process for preparation of optically pure or optically enriched enantiomers of sulphoxide compounds of formula (I), such as omeprazole and structurally related compounds, as well as their salts and hydrates. The said process comprises
a) providing, a mixture of enantiomers of the sulphoxide compound of formula (I) as starting material, in an organic solvent; said enantiomers having R and S configurations at the sulfur atom of the sulphoxide group; b) treating the mixture of enantiomers, in the organic solvent, with a chiral host; c) separating the adduct formed by the enantiomer and the chiral host; d) if desired, repeating the operation of step (b); e) treating the adduct obtained in step (c) or (d) with metal base selected from Group I and Group II metal, thereby obtaining metal salt of one of the optical isomers of the sulphoxide compound in optically pure or optically enriched form; f) optionally, converting the Group I metal salt of optically pure or optically enriched form the optical isomers of the sulphoxide compound obtained in step (e) to magnesium salt.
| 2
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a 35 U.S.C. §371 national phase entry of, and claims priority to, PCT Application No. PCT/US2014/055862, filed Sep. 16, 2014, and entitled “Multistage Stacked Disc Choke” which is hereby incorporated in its entirety by reference herein for all purposes.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] Chokes have been used for decades in oilfield operations to reduce the fluid pressure of high pressure flowing fluids. The life of a choke is significantly reduced by cavitation and/or flashing that occurs when high pressure fluids are decompressed. Cavitation occurs when the pressure of a fluid drops below its vapor pressure and then recovers to above its vapor pressure. The desired pressure drop across a choke can cause cavitation, resulting in voids, such as small bubbles, in the fluid. When the pressure recovers to above its vapor pressure near the outlet, the voids can implode and collapse. The repetitive implosions near metal surfaces of the outlet can cause material loss.
[0005] Various attempts have been made to reduce cavitation and flashing in chokes. Multiple stages can be used to spread the overall desired pressure drop across the stages to help the pressure remain above its vaporization pressure as the pressure is reduced. Some of the challenges of multistage chokes are the price of the choke, which may be 10-15 times greater than a single stage choke, the short wear life of the choke when solids are present, and clogging of very fine labyrinth passages within a choke.
[0006] Multiple concentric cages or multiple stacked disks may be used to define a torturous path through a choke. Stacked disks are disclosed, for example, are made by Weir Power & Industrial in the USA under the brand X-Stream choke. However, the cost of manufacturing multiple disks with varying diameter staggered cylinders extending from the disk face is a significant drawback to these designs.
[0007] Therefore, there remains a need for an improved system and method for a multiple stacked disk choke that can be efficiently produced.
SUMMARY OF THE INVENTION
[0008] The invention provides an improved multistage stacked disc choke that can be manufactured from a sintering process. The choke includes a plurality of stacked disks that are produced in a “green” sintered state, then stacked, and sintered into a monolithic assembly. The stacked disk monolithic assembly is fitting into a steel cage with porting that aligns with porting on the outside surface of the stacked disks. A seat can be inserted into the steel cage and the assembly inserted into the choke. A plug is then able to be moved axially within the choke to adjust the opening and closing of the porting in the stacked disk assembly. The radial flow paths through the disks are offset from stage to stage, so that the flow impinges on surfaces as the flow progresses through the disks. The porting has a circular cross section to minimize wear and reduce stress risers.
[0009] The disclosure provides a multistage stacked disk choke, comprising: a housing having a high pressure inlet port and a low pressure outlet port; a monolithic assembly of at least two sintered disks comprising a circular tubular inlet port in fluid communication with an outer periphery of the monolithic assembly and in fluid communication with the housing inlet port, a circular circumferential galley formed between the outer periphery and an inner periphery of the monolithic assembly and formed to intersect the circular tubular inlet port, and a circular tubular outlet port in fluid communication with the circular circumferential galley, and an internal bore radially inward from the tubular outlet port and in fluid communication with the tubular outlet port; a cage having a bore with a cross section sized to receive the monolithic assembly within the bore, the cage having a cage inlet port in fluid communication with the circular tubular inlet port of the monolithic assembly; a seat in the choke configured to longitudinally support the monolithic assembly, the seat having a seat bore in fluid communication with the low pressure outlet port of the choke; and a plug sized to move longitudinally inside the bore of the monolithic assembly and selectively restrict flow through the tubular outlet port, the tubular inlet port, or a combination thereof, such that in operation fluid flows from the high pressure inlet port through the cage inlet port into the circular tubular inlet port of the monolithic assembly, and is redirected into the circular circumferential galley intersecting the circular tubular inlet port and into the circular tubular outlet port offset from the circular circumferential galley, into the bore of the monolithic assembly to the bore in the seat, and out through the low pressure outlet port.
[0010] The disclosure provides a method of flowing fluid through a choke, the choke with a housing having a high pressure inlet port and a low pressure outlet port; a monolithic assembly of at least two sintered disks comprising a circular tubular inlet port in fluid communication with an outer periphery of the monolithic assembly and in fluid communication with the housing inlet port, a circular circumferential galley formed between the outer periphery and an inner periphery of the monolithic assembly and formed to intersect the circular tubular inlet port, and a circular tubular outlet port in fluid communication with the circular circumferential galley, and an internal bore radially inward from the tubular outlet port and in fluid communication with the tubular outlet port; a cage having an internal bore with a cross section sized to receive the monolithic assembly within the bore, the cage having a cage inlet port in fluid communication with the circular tubular inlet port of the monolithic assembly; a seat in the choke configured to longitudinally support the monolithic assembly, the seat having a seat bore longitudinally aligned with the bore of the monolithic assembly and fluid communication with the low pressure outlet port of the choke; a plug sized to move longitudinally inside the bore of the monolithic assembly and selectively restrict flow through the tubular outlet port, the tubular inlet port, or a combination thereof, the method comprising: allowing fluid to flow from the high pressure inlet port through the cage inlet port into the circular tubular inlet port of the monolithic assembly, into the circular circumferential galley intersecting the circular tubular inlet port and into the circular tubular outlet port offset from the circular circumferential galley, into the bore of the monolithic assembly to the bore in the seat, and out through the low pressure outlet port.
[0011] These and further features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a partial cross-sectional schematic view of one embodiment of a multistage stacked disk choke having a monolithic assembly.
[0013] FIG. 2 is a schematic view of an enlarged portion of the exemplary choke of FIG. 1 .
[0014] FIG. 3 is a perspective schematic view of a plurality of disks to form the monolithic assembly of stacked disks for the choke.
[0015] FIG. 4 is a side view schematic of an exemplary monolithic assembly of stacked disks assembled for sintering in an oven.
[0016] FIG. 5 is a partial cross-sectional schematic view of a monolithic assembly.
[0017] FIG. 6 is an alternative embodiment of a multistage stacked disk choke having a combination of zones.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0018] The Figures described above and the written description of specific structures and functions below are not presented to limit the scope of what Applicant has invented or the scope of the appended claims. Rather, the Figures and written description are provided to teach any person skilled in the art to make and use the inventions for which patent protection is sought. Those skilled in the art will appreciate that not all features of a commercial embodiment of the inventions are described or shown for the sake of clarity and understanding. Persons of skill in this art will also appreciate that the development of an actual commercial embodiment incorporating aspects of the present disclosure will require numerous implementationspecific decisions to achieve the developer's ultimate goal for the commercial embodiment. Such implementation-specific decisions may include, and likely are not limited to, compliance with system-related, business-related, government-related and other constraints, which may vary by specific implementation, location and from time to time. While a developer's efforts might be complex and time-consuming in an absolute sense, such efforts would be, nevertheless, a routine undertaking for those of ordinary skill in this art having benefit of this disclosure. It must be understood that the inventions disclosed and taught herein are susceptible to numerous and various modifications and alternative forms. The use of a singular term, such as, but not limited to, “a,” is not intended as limiting of the number of items. Also, the use of relational terms, such as, but not limited to, “top,” “bottom,” “left,” “right,” “upper,” “lower,” “down,” “up,” “side,” and the like are used in the written description for clarity in specific reference to the Figures and are not intended to limit the scope of the invention or the appended claims. Where appropriate, one or more elements may have been labeled with an “A” or “ 8 ” to designate various members of a given class of an element. When referring generally to such elements, the number without the letter can be used. Further, such designations do not limit the number of members that can be used for that function.
[0019] The disclosure provides an improved multistage stacked disc choke that can be manufactured from a sintering process. The choke includes a plurality of stacked disks that are produced in a “green” sintered state, then stacked, and sintered into a monolithic assembly. The stacked disk monolithic assembly is fitting into a steel cage with porting that aligns with porting on the outside surface of the stacked disks. A seat can be inserted into the steel cage and the assembly inserted into the choke. A plug is then able to be moved axially within the choke to adjust the opening and closing of the porting in the stacked disk assembly. The radial flow paths through the disks are offset from stage to stage, so that the flow impinges on surfaces as the flow progresses through the disks. The porting has a circular cross section to minimize wear and reduce stress risers.
[0020] FIG. 1 is a partial cross-sectional schematic view of one embodiment of a choke. FIG. 2 is a schematic view of an enlarged portion of the exemplary choke of FIG. 1 . The figures will be described in conjunction with each other. A choke 10 includes a housing 12 having a high pressure inlet port 14 and a low pressure outlet port 16 . A cap 38 can be coupled to the housing 12 and an actuator 32 coupled to the cap. The actuator 32 can be manual or powered, and can be remotely controlled. As an exemplary actuator, a handle 36 is shown to turn elements in a gear assembly 34 to longitudinally raise and lower the plug 28 .
[0021] A cage 18 is positioned within the housing 12 and has an internal bore 19 . A monolithic assembly 20 can be formed of pressure reducing disks and mounted in the cage 18 at least partially within the bore 19 . A choke seat 20 may be coupled to the housing 12 to receive the cage 18 and/or the monolithic assembly 20 . The cage 18 may be shrunk fit or otherwise secured to the choke seat 22 . The monolithic assembly 20 is formed with an internal bore 24 fluidicly coupled with the low pressure outlet port 16 . A plug 28 can longitudinally move by motion of the actuator 32 along the centerline 58 within the monolithic assembly bore 24 to control the flow through the monolithic assembly by at least partially blocking portions therein. In FIG. 1 , the plug 28 is shown on the left side of the centerline 58 partially blocking the flow through the monolithic assembly in a partially open position on the choke, and the plug is shown on the right side of the centerline 58 in a raised position that is not at least partially blocking flow through the monolithic assembly so that the choke is in a fully open position.
[0022] The monolithic assembly 20 generally includes a stack of disks with internal ports formed therein by the combined assembly of the disks. In at least one embodiment, the longitudinal middle portion of the monolithic assembly include one or more disks 42 that have partial passageways formed on both faces of the disks that when coupled together form the whole passageways. The top and bottom of the monolithic assembly include one or more end disks having partial passageways formed on one face to be coupled with the face of an adjacent disk 42 to form the whole passageways, while the other face of the end disks may have no partial passageways formed thereon. Further details are described herein.
[0023] In operation, generally fluid would enter through the side of the housing 12 through the inlet port 14 and flow into an annulus in the housing around the cage 18 and through the cage inlet ports 40 . The fluid can enter the monolithic assembly 20 and flow therethrough for a pressure reduction, and then into the bore 24 of the monolithic assembly, subject to restricted flow from the plug 28 positioned in the bore. The fluid can exit through the outlet port 16 at a reduced pressure.
[0024] FIG. 3 is a perspective schematic view of a plurality of disks to form the monolithic assembly of stacked disks for the choke. A disk 42 has several semicircular flow passageways for forming the different flow passages therein. In the exemplary embodiment, three stages are shown. However, it is understood that any number of stages (lesser or greater) can be used and the exemplary embodiment is for illustrative purposes.
[0025] Starting from the outer periphery 44 of the disks that collectively form the monolithic assembly, a plurality of semi-circular tubular inlet ports 46 are formed radially around the outer periphery 44 as a first stage in the disk 42 A and ultimately the monolithic assembly 20 . The inlet ports 46 intersect a semi-circular first circumferential galley 48 . The galley 48 provides a pathway for flow from the inlet ports 46 to be distributed in a circumferential manner.
[0026] On a distal side of the galley 48 from the inlet ports, a plurality of semicircular access ports 50 are formed radially around the galley 48 as a second stage of flow in the disk. The semi-circular access ports 50 are generally offset from a radial alignment with the inlet ports 46 . The offset provides an obstruction of the galley wall to the incoming flow from the inlet ports to cause turbulence and pressure reduction as the fluid impinges on the galley wall from the inlet ports and must turn several angles by first turning into the galley, and then turning into the radially offset access port 50 . In at least one embodiment, one or more ports on one side of the galley can be offset about halfway between one or more ports on the other side of the galley. Further, the cross-sectional size of the ports in the different stages can vary as may be determined from flow considerations.
[0027] The disk face 45 can further be formed with a semi-circular second circumferential galley 52 , so that the semi-circular access port 50 intersects the semicircular second circumferential galley 52 to distribute flow from the access port into the second galley.
[0028] A semi-circular tubular outlet port 54 is formed to intersect the semicircular second circumferential galley 52 as a third stage. Likewise, the semi-circular tubular outlet ports 54 can be formed around the disk face 45 in an alignment that is radially offset from the access ports 50 . The offset alignment similarly allows fluid flowing through the access port 50 to encounter resistance as the fluid impinges the wall of the galley 52 and must turn at angles in the galley to exit through the outlet ports 54 , thus causing turbulence, further flow resistance, and pressure reduction. The disk 42 A includes an inner periphery 56 that forms a bore 60 of the disks 42 , where the bore is generally aligned with a centerline 58 . The cumulative bores 60 of multiple disks 42 can form the bore 24 of the monolithic assembly described above.
[0029] Disk 42 B can generally be formed in the same manner as disk 42 A. For example, the underside face 45 A of the disk 42 A can be formed similarly as the upper face 45 B of the disk 42 B, so that a semi-circular tubular inlet port 46 A on disk 42 A has a mating semi-circular tubular inlet port 46 B on disk 42 B, and likewise a semi-circular first circumferential galley 48 A has a mating semi-circular first circumferential galley 48 B, a semi-circular access port 50 A has a mating semi-circular access port 50 B, a semi-circular second circumferential galley 52 A has a mating semi-circular second circumferential galley 52 B, and a semi-circular tubular outlet port 54 A has a mating semi-circular tubular outlet port 54 B. When the disks are mounted together and properly aligned face to face, the semi-circular portions of the disk 42 A coupled to the semi-circular portions of the disk 42 B complete the cross-sectional circular shapes to form the circular ports and flow passages described herein. Other disks could be used and are contemplated, so that for example, the underside face of disk 42 B could be formed in a similar manner as the top face of disk 42 A and further stacked on top or under other disks to form additional flow passages as described herein. The circular shapes assist in reducing erosion that would otherwise be encompassed by sharp angles and corners. The term “circular” is used broadly herein and includes generally round, oval, and elliptical shapes, and other shapes that are absent 90-degree corners of a cross-section of a square or rectangle.
[0030] FIG. 4 is a side view schematic of an exemplary monolithic assembly of stacked disks assembled for sintering in an oven. The disks are generally formed from tungsten carbide or other abrasive resistant (but generally brittle) material, such as hardened stainless or nickel-based metals. Due to difficulties in machining such materials, it is envisioned that the individual disks 42 be formed as molded shapes through powder metallurgy or other fabrication processes. However, the disks 42 are prepared to a “green” state, such that they can retain their shapes for temporary handling, but require further processing for completion. When the disks are formed in a green state so that they can be handled, the disks can be assembled together, for example, in the manner shown in FIG. 4 . To retain the stack of green disks in a proper alignment and shape, the disks can be held in position with an exemplary fixture 76 . The assembly of the several disks and fixture 76 can be placed in a sintering oven 74 , using for example a sintering hot isostatic pressing operation, for completion of the process to sinter the green disks together into the monolithic assembly 20 . Thus, when the disks are assembled, the face of one disk with its semicircular portions of the flow passageways mates with a corresponding face of an adjacent disk and its semi-circular portions to form the full circular passageways shown therein. For example, a semi-circular tubular inlet port 46 A of disk 42 A can be aligned with a semi-circular tubular inlet port 46 B of the disk 42 B, so that the semicircular tubular inlet ports 46 A, 46 B form in combination a circular tubular inlet port 62 A.
[0031] In some embodiments, the monolithic assembly will include one or more end disks 70 . The end disks 70 are similar to the disks 42 with the primary difference being that the end disks have only one face formed with the semi-circular flow passageways. The other face is generally absent such flow passageways, because no choking function through the valve is contemplated across the end faces 72 A and 72 B of the end disks 70 A and 70 B, respectively.
[0032] FIG. 5 is a partial cross-sectional schematic view of a monolithic assembly, more specifically, a partial cross section of the monolithic assembly 20 to the left side of the centerline 58 of monolithic bore 24 . The monolithic assembly 20 has been sintered from the assembly of green disks 42 , and thus the lines shown in FIG. 5 and the demarcations of each of the disks described in FIG. 5 , are for illustrative purposes and may not in fact exist as separate units or discreet surfaces between the disks after the sintering process in the produced article. \
[0033] Starting from the left of the sheet with the outer periphery 44 of disks of the monolithic assembly, the top end disk 70 A is coupled to the disk 42 A with flow passageways aligned to allow flow therethrough. The end disk 70 A can have an end face 72 A which generally will not have partial flow passages formed thereon, because no flow is expected to be controlled over the end face. In this particular cross-section, the tubular inlet port 62 B at the interfaces between the end disk 70 A and disk 42 A is shown existing in a different plane from the particular cross-section chosen. The circular tubular inlet port 62 B intersects the circular tubular first galley 64 A formed by the mating coupling of the semi-circular first circumferential galleys 48 A and 48 B. In the plane of the particular cross-section chosen for FIG. 5 , the semi-circular access ports 50 A and 50 B are shown in solid lines and form the circular tubular access port 66 A. In the exemplary embodiment with optional other stages, a circular tubular second galley 67 is formed from the semi-circular second circumferential galleys 52 A and 52 B. A circular tubular outlet port 68 A is formed radially inward from the second galley 67 A by the mating coupling of semi-circular tubular outlet ports 54 A and 54 B. Thus, the circular tubular inlet port 62 B and the circular tubular outlet port 68 A are generally not aligned radially with the circular tubular access port 66 A. Further, the circular tubular inlet port 62 B may also not be radially aligned with the circular tubular outlet port 68 A.
[0034] In a similar fashion, the faces of the disks 42 A and 42 B can be coupled together in the sintering process to form flow passageways therebetween. In the particular cross-section shown, the circular tubular inlet port 62 A is formed from the two semi-circular tubular inlet ports 46 A and 46 B. In the embodiment shown, the circular tubular inlet port 62 A may not be radially aligned with the inlet port 62 B. Also, the access port 66 B on the distal side of the circular tubular first galley 64 will generally not be radially aligned with the inlet port 62 A. The outlet port 68 B on the other side of the circular tubular second galley 67 will generally not be aligned with the access port 66 B, and mayor may not be aligned with the inlet port 62 A.
[0035] An end disk 70 B may be coupled with the disk 42 B to form the flow passages therethrough similarly as described above relative to the end disk 70 A and disk 42 A. The inlet port 62 C is generally not aligned with the access port 66 C and the access port 66 C is generally not aligned with the outlet port 68 C. In the embodiment shown, the access port 66 A can be radially aligned with the access port 66 C. The end disk 70 B has an end face 72 B that may not have access ports formed thereon, because no flow is expected to be directed across the end face 72 B for control and pressure reduction.
[0036] Thus, the monolithic assembly 20 can form flow passageways from the outer periphery 44 to the inner periphery 56 of the monolithic assembly with radially offset passageways for pressure reduction across multiple stages, but in a manner that is cost effective by preforming certain portions of the assembly and then sintering the portions into a final monolithic assembly.
[0037] FIG. 6 is an alternative embodiment of a multistage stacked disk choke having a combination of zones. The choke 10 is similar to the choke described above, but includes a zoned monolithic assembly 78 and related flow passages through the cage. There are flow regimes when a high flow does not need multistages for a choke, such as to avoid cavitation, but other flow regimes through the same choke can use multistages for the choke. A combination choke having different flow zones for the stages can be used to satisfy the multiple flow regimes.
[0038] In the exemplary choke 10 , the housing 12 includes a high pressure inlet port 14 and a low pressure outlet port 16 . A cage 18 is disposed in the choke housing and has a bore 19 to receive the zoned monolithic assembly 78 having a bore 24 . A seat 22 is positioned below the assembly 78 and has a bore 26 in fluid communication with the bore 24 . A plug 28 is coupled to a stem 30 and selectively moveable along a longitudinal centerline 58 within the bore 24 of the zoned monolithic assembly 78 . The cage 18 has at least one cage inlet port 84 for a first zone of the zoned monolithic assembly 78 and at least one cage inlet port 40 for a second zone of the zoned monolithic assembly 78 .
[0039] The zoned monolithic assembly 78 includes a first zone 80 having an assembly inlet port 86 in fluid communication with the cage inlet port 84 on an upstream side and the bore 24 on a downstream side. The first zone 80 can have larger, more open flow passageways than the second zone to allow higher flows with less flow resistance in the choke in a first flow regime. For illustrative purposes and without limitation, the embodiment shown in FIG. 6 is representative of a single stage for the first zone 80 in the zoned monolithic assembly 78 .
[0040] The zoned monolithic assembly 78 also includes a second zone 82 having the inlet ports and other ports in the monolithic assembly that are described in more detail in reference to FIGS. 3, 4, and 5 . The inlet ports of the second zone 82 are in fluid communication with the cage inlet port 40 on an upstream side and the bore 24 on a downstream side. The second zone 82 can have smaller, more restrictive and circuitous flow passageways than the first zone 80 to cause more pressure drop at lower flows through the choke in a second flow regime. For illustrative purposes and without limitation, the embodiment shown in FIG. 6 is representative of a multistage assembly having three stages in the zoned monolithic assembly 78 .
[0041] Optionally, the zoned monolithic assembly 78 can be split into separate assemblies of the first zone 80 and the second zone 82 and are included herein as a “monolithic assembly.”
[0042] In operation, when a high flow rate occurs, the stem 30 can move the plug 28 longitudinally upward in the bore 24 to allow higher flows through the cage inlet port 84 and first zone 80 of the monolithic assembly, and generally through the second zone as well. As more pressure drop in the flow is desired, the plug can be extended into the bore 24 to at least partially restrict the flow through the first zone and force a higher percentage of the flow through the second zone causing a greater pressure drop. The plug 38 can be further extended to restrict entirely flow through the first zone and at least partially or fully restrict flow through the second zone.
[0043] The monolithic assembly can be made without requiring stacked disks by using recent technological advances in additive manufacturing also known as three-dimensional printing. Under such technology, additive manufacturing or 3 D printing refers to any of various processes for making a three-dimensional object primarily through additive processes in which successive layers of material are laid down under computer control. Such processes can use metal sintering forms of additive manufacturing, including without limitation, selective laser sintering and direct metal laser sintering. Thus, the lines in FIG. 4 representing the prior stacked disks would not be present in such an embodiment.
[0044] Other and further embodiments utilizing one or more aspects of the invention described above can be devised without departing from the spirit of Applicant's invention. For example and without limitation, it is possible to have any number of stages, any number of zones for different flow regimes, to have an assembly without end disks with the understanding that any semi-circular flow passages existing on the top and bottom faces of the monolithic assembly may not be used for flow reduction, to not have multiple sets of access ports for various stages between the inlet and outlet ports, or to have no access ports so that the inlet ports and outlet ports are separated by a galley directly.
[0045] Further, the various methods and embodiments of the system can be included in combination with each other to produce variations of the disclosed methods and embodiments. Discussion of singular elements can include plural elements and vice-versa. References to at least one item may include one or more items. Also, various aspects of the embodiments could be used in conjunction with each other to accomplish the understood goals of the disclosure. Unless the context requires otherwise, the word “comprise” or variations such as “comprises” or “comprising,” should be understood to imply the inclusion of at least the stated element or step or group of elements or steps or equivalents thereof, and not the exclusion of a greater numerical quantity or any other element or step or group of elements or steps or equivalents thereof. The device or system may be used in a number of directions and orientations. The term “coupled,” “coupling,” “coupler,” and like terms are used broadly herein and may include any method or device for securing, binding, bonding, fastening, attaching, joining, inserting therein, forming thereon or therein, communicating, or otherwise associating, for example, mechanically, magnetically, electrically, chemically, operably, directly or indirectly with intermediate elements, one or more pieces of members together and may further include without limitation integrally forming one functional member with another in a unity fashion. The coupling may occur in any direction, including rotationally.
[0046] The order of steps can occur in a variety of sequences unless otherwise specifically limited. The various steps described herein can be combined with other steps, interlineated with the stated steps, and/or split into multiple steps. Similarly, elements have been described functionally and can be embodied as separate components or can be combined into components having multiple functions.
[0047] The invention has been described in the context of preferred and other embodiments and not every embodiment of the invention has been described. Obvious modifications and alterations to the described embodiments are available to those of ordinary skill in the art. The disclosed and undisclosed embodiments are not intended to limit or restrict the scope or applicability of the invention conceived of by the Applicant, but rather, in conformity with the patent laws, Applicant intends to protect fully all such modifications and improvements that come within the scope or range of equivalent of the following claims.
|
A multistage stacked disk choke includes a housing having a high pressure inlet port and a low pressure outlet port, an assembly, a cage, a seat, and a plug. The assembly includes: a tubular inlet port, a galley intersecting the tubular inlet port, a tubular outlet port, and a bore inward from the tubular outlet port. The cage has an inlet port in communication with the tubular inlet port. The seat is configured to support the assembly. The plug moves inside the assembly bore and restricts flow through the tubular outlet port and/or the tubular inlet port. Operation fluid flows from the high pressure inlet port through the cage inlet port into the tubular inlet port and is redirected into the galley and into the tubular outlet port into the bore of the assembly to a bore in the seat, and out through the low pressure outlet port.
| 5
|
TECHNICAL FIELD
This invention relates to a multi-tank/multi-pump water pressure system, particulary the application of the pump control mechanism.
BACKGROUND ART
The prior art researched has clearly shown a number of techniques used to provide water through various booster systems. These techniques offer a number of options with various levels of success, in providing controlled water booster systems.
U.S. Pat. No. 4,344,741 (TOMOHIKO TAKI) shows an automatic supply system with a single tank having a controlled air charge, preventing the release of water from the pneumatic tank from a single pump supply to maintain a constant source of water.
U.S. Pat. No. 4,290,735 (SULKO) shows a plurality of pumps each being of a capacity to provide high head and volume disposed into a common manifold to provide pressure boosted water in a highrise building using a pressurestatic switch as means of control consisting of various control switches and relays, with an auxiliary pump having an accumulator tank.
U.S. Pat. No. 3,775,025 (MAHER & MAHER) shows a constant pressure pumping system unit consisting of two pumps, one being of variable speed providing a constant pressure, whereas the second pump provides constant speed with control switches providing the perimeters of the system.
U.S. Pat. No. 3,746,471 (GRAY & ANDERSON) shows a water pressure booster system using auxiliary pump to super charge pressurized reservoir, with a plurality of pumps controlled by various relays and sensing switches.
U.S. Pat. No. 3,744,932 (PREVETT) shows an automatic sequence control system for pump motors. This system provides automatic controlling of a plurality of pumps using various control switches, flow meters, relays along with logic gates thus providing a complex control system.
U.S. Pat. No. 3,639,081 (GRAY & ANDERSON) shows a liquid pressure booster system with cutoff for minimum flow levels consisting of a plurality of constant speed pumps and pressure-regulating valves along with time delay relays and a single pressurized tank with various other complex electrical controls.
To the contrary, none of the references show a "MULTI-TANK/MULTI-PUMP WATER PRESSURE BOOSTER SYSTEM" presented by the inventor.
BACKGROUND AND SUMMARY
The present invention relates to tank type water pressure booster systems employing constant speed pumps, and more specifically it relates to water pressure booster systems employing hydropneumatic bladder or diaphragm type tanks and constant speed electrically driven pumps automatically sequenced to operate to satisfy water system flow demand requirements throughout the full system multi-pump capacity without the utilization of control or timing relays or solid state electrical/electronic timing/controlling devices or flow actuated devices to provide water throughout the full system design range at a specified increase of pressure and maintained within acceptable tolerances of a specified design pressure to suit domestic water system service requirements. The term constant pressure is purposely avoided as it is in reality a misnomer in the pumping industry and is both highly impractical and virtually unobtainable in economical domestic water pressure booster systems. Actual system pressure variation of plus five percent, minus ten percent in low pressure (up to 150 PSI design pressure) booster applications is not only acceptable, but quite common and frequently utilized in establishing design parameters of control. In high pressure applications a lesser percentage of pressure variation usually will be found, although a pressure variation of plus 10 PSI, minus 20 PSI on a 250 PSI system is not uncommon. Multipump water booster systems of both tank and tankless types are supplied with inlet pressure either from a conduit or reservoir source of supply at a pressure that is usually lower than is required to meet the domestic water service requirements of the facility being supplied. The pumps are parallel connected and fitted with appropriate isolation and discharge check valves to permit individual operation or simultaneous operation while pumping from a common source into a common conduit, and providing a specified increase in pressure. When required or desired, these pumping systems may be furnished with pressure reducing valves connected either one on the discharge of each pump before entering the common high pressure conduit, or in any desired arrangement of parallel connected pressure reducing valves installed between the common high pressure conduit and the service to the facility. The systems are designed to sequence the pumps as required to satisfy the flow demand of the facility being supplied; automatically selecting the pump or any combination of pumps best suited to satisfy system flow demand at any given time, and (when furnished with auto shut off feature) to turn all pumps off under conditions of no demand. When a system is designed having two or more equally sized pumps, a means of automatic or manual alternation or sequencing selection is usually provided in order to equalize wear and operating time.
Systems furnished with the design features as described above have been found to be highly energy efficient and economical of operation since they have the ability to select the smallest energy consuming combination of pumps required to be in operation to suit the system demand at any given time and (when so equipped) to shut off with zero demand. The application of a hydropneumatic tank (usually an optional item) to such systems further enhances the energy conservation aspect of these systems, since it enables the reservoir capacity of the tank to supply low volume usage to the facility while allowing the system pressure to be reduced from the maximum high value when the pump shuts off at zero demand (+≡to + PSI) to an acceptable low value for system operation (generally -10 to -°PSI). Thus a volume of water can be furnished to the facility without starting a pump. The disadvantages found in most of the above described systems are that the tank and zero or low demand shut off feature is provided only as extra cost options, there are some systems lacking in the ability of the controls to perform a claimed function, and in virtually all systems the method to attain the functions is by means of costly control and timing relay circuitry or solid state electronic control devices coupled with also costly flow sensing devices. Flow and current sensing devices are the most commonly used items for sequencing control of present day state of the art multi-pump automated pump control systems. Both have the common disadvantage of working in combination with timing relays which function to start the next pump of the system instantaneously when the signal from the flow or current sensing device is received, and to maintain the pump in operation for a predetermined period of time. During this transition, the prior operating pump is usually sequenced off.
Brief surge demands are extremely common in many types of buildings, such as hotels, schools, office buildings, apartments, hospitals, entertainment centers, etc. With each occurence, a larger pump may be sequenced on for the predetermined time setting of the timing device while a smaller pump is sequenced off. In extreme cases continuous back and forth cycling between a small pump and a larger pump in a system may continue without cessation throughout the greater part of a day. This is not only hard on the equipment but also wasteful of energy. It is not uncommon to employ time clock control to prevent such cycling from occuring.
Most equipment users desire and specify a type of pump failure feature that will provide an alarm indication and start an alternate pump in the event of failure to a pump while in the operational sequence. This feature is a standard extra cost option for failure of the lead (number one) pump in most designed pumping systems, however most manufacturers do not offer a feature to protect from failure to a main pump except on a custom engineered basis. Another occasionally requested feature by system users is the high suction pressure shut off. With this feature, the pumps are programmed to shut off and remain off if the inlet pressure to the system reaches a predetermined high level sufficient to supply the facility without the boost in pressure provided by the pumps. This too is usually offered as an extra cost option, it is highly desireable for installations wherein the input pressure has wide variation since it automatically prevents the pumps from running unnecessarily.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 shows the basic piping arrangement of the water booster system constructed in accordance with an embodiment of the inventor;
FIG. 2 is a combined circuit and systematic diagram of the control system according to the present invention;
FIG. 3 is as FIG. 1, showing pressure reducing values added to the system;
FIGS. 4 and 5 show the controls for adding additional pumps to the system with the means of tank three;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a diagramatic form of the present invention. Inlet source 15 provides water to suction manifold connected to pumps indicated respectively as 1, 2, 3, which are connected for parallel operation when energized. The output of pump number 1 flows through check valve 36 and through gate valve 39, into service line 6; pump 2 flows through check valve 37 and through gate valve 40 into line 6; pump 3 flows through check valve number 38 and through gate valve 41 into line 6. Primary tank 4 is connected to line 6 by line 30 with a service valve 42 adjacent to line 6 and an orifice check valve 11 between tank 4 and service valve 42 with sensing point 51 directly adjacent to discharge of primary tank 4. Secondary tank 5 is connected to line 6 by line 32 which flows through solenoid valve 13 and intersects line 31 and flows into line 30 between orifice check valve 11 and servicing valve 42, and into line 6. Line number 32 has a sensing point 52 adjacent to secondary tank 5 and a bypass line 33 with check valve 12 around solenoid valve 13 returning into line 32. Pressure sensing switch two 8, pressure sensing switch three 9 and pressure sensing switch four 10 are all connected to sensing point 52 by line 34. Pressure switch one and the high pressure side of pressure differential switch 14 are connected to the sensing point 51 by line 35. The low pressure side of pressure differential switch 14 is connected to sensing point 53 by line 79.
FIG. 2 is an electrical schematic which is verbally defined in the SEQUENCE OF OPERATION describing the function of each component in operating detail.
FIG. 3 is a diagramatic form of the present invention as described in FIG. 1 with the addition of the following: pressure reducing valves 47, 48, 49 and 50 which are placed in lines 70, 73, 71 and 72 respectively.
FIGS. 4 and 5 is an electrical and piping schematic which is verbally defined in the sequence of operation describing the function of each component in operating detail.
SEQUENCE OF OPERATION
For explanatory purposes, let it be assumed that electrical power is being provided to the system, the system is properly connected hydraulically to inlet and outlet plumbing, water is being supplied to the inlet by a regulated source of supply, and the system is set up for automatic operation. Present system demand is zero, both primary and secondary tanks are fully charged and all pumps are idle due to the zero demand condition. This can be referred to as static or standby service condition. Referring to the drawings, FIGS. 1 and 2, the sequence which will occur when demand is placed on the system will be as follows: Water will be drawn from the primary tank FIG. 1, (4) to service needs, FIG. 1, (6) until the pressure in the primary tank is reduced to the set point of pressure switch PSI, FIG. 1, (7) this is usually 10 to 20 PSI below the pressure at which PSI, FIG. 1, (7) opens to stop the number one pump, FIG. 1, (1). When pressure switch one closes its contacts (refer now to FIG. 2, (7) it completes an electrical circuit through the normally closed auxiliary starter contacts FIG. 2, (16 and 17) of motor starters M2 and M3 FIG. 2, (18 and 19) and through the closed contacts of hand off auto selector switch FIG. 2, (21) to energize motor starter one FIG. 2, (18) and its running indicator lamp FIG. 2, (24). Simultaneously energized by pressure switch one is the secondary tank solenoid valve FIG. 1, (13) and FIG. 2, (13). Pump number one is started in the conventional manner by closure of the motor starter contacts, supplying power to the motor windings (as will be pumps 2 and 3 FIG. 1, in later descriptions).
Water will now be supplied to the service both from the number one pump and from the secondary tank through the now opened normally closed solenoid valve FIGS. 1 and 2, (13). The primary tank FIG. 1, (4) places no appreciable draw on the system because the fill rate is restricted to a small volume by the orificing through the seat of the check valve FIG. 1, (11). If the demand is small, the pressure in the secondary tank FIG. 1, (5) will be reduced only slightly, and the number one pump will continue in operation to supply service demands and recharge the primary tank FIG. 1, (4). When demand is increased beyond the capacity of the number one pump the secondary tank pressure will quickly be reduced by the discharge of water to service needs through the open solenoid valve FIGS. 1 and 2, (13). When pressure is reduced to the set point of pressure switch two FIGS. 1 and 2, (8) the contacts close to complete a circuit through the closed contacts of the electric alternator FIG. 2, (28) and through the closed contacts of the auto section of the number two pump hand off auto selector switch FIG. 2, (22) to the coil FIG. 2, (19) of the number two pump magnetic motor starter, placing number two pump FIG. 1, (2) into operation and energizing the number two pump running indicator lamp FIG. 2, (25). Simultaneously with closure of pressure switch two contacts, the coil of the electric alternator FIG. 2, (27) will become energized. Simultaneous with actuation of magnetic motor starter number two the auxiliary starter contact M2 FIG. 2, (16) opens to break the operating circuit to pump number one. Pump number one stops and service demand is now supplied by the output of pump number two through the 20 to 40 percent system design capacity range.
Both primary and secondary tanks accept recharge pressure when service pressure is greater than tank pressure, through the orifice check valve FIG. 1, (11) to the primary tank and through the small bypass line FIG. 1, (33) and check valve, FIG. 1, (12) to the secondary tank. Conversely with increasing service demands and reducing pressure, both the primary and secondary tanks will supply water as available to service needs; the primary tank through the unrestricted direction of flow through the orifice check valve FIG. 1, (11) and the secondary tank through the open solenoid valve FIG. 1, (13). With increased demand and further reduction in pressure to the set point of pressure switch three FIGS. 1 and 2, (9) the contacts close to complete an operating circuit to the number three magnetic motor starter FIG. 2, (20) and to the number three pump running indicator lamp FIG. 2, (26). Pressure switch three also completes a redundant operating circuit to pump number two, through the upper set of contacts FIG. 2, (9) which has no effect since pump two is already in operation. Likewise the normally closed M3 auxiliary contact FIG. 2, (17) opens but performs no function because the required function (stopping the number one pump) was previously performed by the M2 auxiliary contact FIG. 2, (16). The number three pump is started by the magnetic starter in the conventional manner and the number two and three pumps operate in parallel to provide service requirements through the 40 to 80 percent range of system design capacity. While in this mode of operation, both primary and secondary tanks continue to function as previously described to charge and discharge to stabilize system output pressure and assist the pumps in meeting service demands. As additional demand is placed upon the system, the pressure will be further reduced to the set point of pressure switch four FIGS. 1 and 2, (10) upon closing its contacts, pressure switch four completes a second operating circuit to the motor starter number one FIG. 2, (18) bypassing the initial start circuit and the cut-out circuit of the M2, M3 FIG. 2, (16) and (17) normally closed auxiliary starter contacts. Starter number one operates, placing number one pump into operation and number one pump running lamp FIG. 2, (24) will be simultaneously lighted. The system is now operating at full design capacity to meet service damands of 80 to 100 percent of full system design capacity and will continue in this mode of operation until service demand is reduced.
When flow demand is reduced, system pressure in both the primary and secondary tanks will increase. Pressure switches PS4, PS3 and PS2 FIG. 2, (7) (8) (9) will be opened in reverse order from that in which they closed. As each switch opens the pump that was being controlled by the respective switch will be stopped. When pressure switch two opens FIG. 2, (8) it will also deenergize the coil of the alternator FIG. 2, (27). When the coil deenergizes the alternator contacts FIG. 2, (28) shift to the opposite position, thereby selecting the number three pump to be the first sequence main pump for the next cycle of operation. When the number two magnetic starter FIG. 2, (19) is deenergized its normally closed auxiliary contact M2 FIG. 2, (16) which completes the restart circuit to number one pump through the previously closed (when pump three was stopped) M3 auxiliary motor starter contact FIG. 2, (17). Pump number one restarts to provide low system demand and recharge the primary and secondary tanks. When the primary tank pressure is increased to the actuation point of switch one FIGS. 1 and 2, (7) the switch opens to stop the pump and return the system to the static service condition where it will remain until such time as demand is placed upon it to begin a new cycle of operation.
STAGING ADDITIONAL PUMPS AS IN FIGS. 4 AND 5 WITH SEQUENCE OF OPERATION
The invention is readily adaptable to controlling additional pumps within a common system without extensive modifications. FIGS. 4 and 5 are provided as an example for field addition of two pumps to the previously described three pump system. To facilitate control, a third tank FIG. 5, (67) of equal or slightly less capacity than the secondary tank is piped in parallel to the secondary tank FIG. 1, (5) and is provided with similar flow control devices consisting of normally closed solenoid valve FIG. 5, (65) and bypass check valve FIG. 5, (55). The check valve and the tank combination are selected to provide a slightly faster rate of recharge than the secondary tank. With the arrangement shown, the added pumps will be controlled by magnetic motor starters M4 and M5 FIG. 4, (56 and 57) and will be entered into the systems operational sequence after the second sequence main pump of the three pump system is started. Control power for the two pumps being added is from the common source supplying the basic three pump system FIGS. 2 and 4, (58 and 59). The only electrical components required to be added to the basic triplex control panel are the auxiliary motor starter contacts M2A and M3A FIG. 4, (60 and 61). Magnetic motor starters M4 and M5 FIG. 4, (56 and 57) with the associated hand off auto control switches FIG. 4, (62 and 63) and the alternator FIG. 4, (64) are used for controlling the pumps being added and can be provided in a separate duplex pump control panel.
When the second sequence main pump of the basic three pump system is started, auxiliary motor starter contacts M2A and M3A FIg. 4, (60 and 61) will both be in the closed position. Power is then applied to the normally closed solenoid valve FIG. 4, (65) on the discharge line FIG. 5, (66) of tank three FIG. 5, (67). Water from tank three is now discharged to augment the output of pumps two and three, FIG. 1, (2 and 3). When pressure drops to the set point of pressure switch PS5 FIGS. 4 and 5, (68) its contacts will close, the alternator coil FIG. 4, (64) will become energized, and power will be applied through the closed contacts FIG. 4, (69) of the alternator and through the closed contacts of the hand off auto selector switch FIG. 4, (62) set in the auto position to the coil of magnetic motor starter M4 FIG. 4, (56). When the main contacts of M4 close, pump number four will be placed into operation to supply additional water to the service. With additional service demand the pressure in tank three FIG. 5, (67) will be reduced further. When it reaches the set point of pressure switch PS6 FIGS. 4 and 5, (77) its contacts will be closed to energize magnetic motor starter M5 FIG. 4, (57) through the closed contacts of hand off auto selector switch FIG. 4, (63). Pumps two, three, four and five now operate simultaneously to supply system demands. If pressure continues to be reduced, pressure switch PS4 FIG. 2, (10) of the basic system will close its contacts at the set point and restart pump number one FIG. 1, (1) of the basic system. Pumps one through five will now operate simultaneously to supply maximum system design capacity to service needs, and will remain in operation until service demand is reduced. When service demand is reduced, the pressure in the secondary tank FIG. 1, (5) and in tank number three FIG. 5, (67) will be increased. Pressure switches PS4, FIG. 2, (10) PS5 FIG. 4, (68) and PS6 FIG. 4, (77) will reopen in reverse order from that in which they closed and stop the respectively controlled pump. When pressure switch PS5 FIG. 4, (68) opens its contacts, the alternator FIG. 4, (64) will become deenergized and shift the contacts FIG. 4, (69) to the opposite position to select pump number five for the first sequence of operation when the next operational cycle requiring pump four or five is required.
GENERAL COMMENTS ON SYSTEM OPERATION
When pump number one is started in the first sequence, the primary tank charge is depleted by approximately 90 percent, and the system pressure is at its lowest operating value. At the instant of pump number one starting, pressure in the system begins to increase, not only from the pump output, but also from the charge in the secondary tank. System control is transferred from the static mode of the primary tank to the dynamic mode of the secondary tank. Thus, the ability to combine the advantage of the large reservoir capacity of the primary tank, and the ability to accurately sequence and provide timing control to the pumps, while operating without overloading, and at the system design pressure, is achieved. More simply stated, the secondary tank controls pump sequencing at system design pressure, while the primary tank controls the static system pressure which is allowed to vary through the optimum differential range of the primary tank. The dual tank feature enables dual pressure sensing to suit the mode of operation, and provides dual range control.
The ability of the two hydropneumatic tanks to augment pump output during dynamic operation provides a high degree of stability and efficiency to the system. Under conditions of varying flow demand, the tanks continually charge or discharge water to assist the pumps in meeting system requirements. Brief surge demands can be supplied by the tank output without switching to a larger pump or starting an additional pump (as occurs with flow activated switching devices). Minimum run periods for the pumps are established by the differential band of the pressure switches employed, and the time period required to increase the pressure in the secondary tank through the range of pressure switch differential. This eliminates the possibility of the pump short cycling (and also eliminates the need for electrical or electronic minimum run timers). In effect, the secondary tank becomes a dampened switching chamber, protected from the effects of surge demands (which can be supplied by the tanks reservoir capacity), is not at all effected by pressure spikes, and provides as the end result a highly stable, accurate and simple means to sequence pumps in automated multipump systems.
The degree of accuracy in switching/sequencing the pumps is limited primarily by the quality and design of the pressure switches and the size of the secondary tank. By sizing the lead pump for a slightly higher pressure than the main pumps, the tanks can be charged to a pressure of 5 to 10 PSI above system design requirements, which then permits sequencing to the first main pump at system design pressure, starting the second main pump slightly (2 to 5 PSI) below system design pressure, and the restart of the lead pump at 5 to 10 PSI below system design pressure. Thus a very narrow band for switching control can be established, and is limited only by the degree of sophistication of the switching devices and the size of the secondary tank.
PUMP FAILURE MODE OF OPERATION
With competitive systems this feature is usually offered as an extra cost option and consists of a relay logic circuit actuated by a pressure switch. The logic is such that should the pressure at any time be reduced to the set point of the pressure switch, conclusion is drawn that the pump that should be operating has failed; usually the conclusion is also drawn that the pump that should have been in operation at the particular time of the occurence was the number one or lead pump. Therefore the title "lead pump failure" is commonly applied to this optional feature. The relay logic applied functions to start the first sequence main pump and lock it into continuous operation until such time as a manual reset button is pressed. An audible or visual alarm is also actuated on this condition. The relay logic may function to remove the failed lead pump from service but does not in all cases do so.
Pump failure feature of the invention is an inherent design characteristic. Because the dynamic control of this system is exercised by means of a pressure being maintained within the secondary tank, the system will simply bypass any pumps in the operating sequence which fail to provide proper output, and select the pump in the next sequence position of operation to meet service requirements. In selecting this alternate pump to provide service demand, it will not be sequenced into continuous operation until manually reset, but will be placed into operation only for so long as is required to meet service demands. The pump will then be shut off in the normal manner and the system will automatically be reverted into the static service condition. The only observable effect will be that if the number one pump was the failed unit, the primary and secondary tanks will not be recharged to the full pressure normally attained when the system sequences into the static service condition. The total system capacity will of course be reduced by the capacity of the failed pump.
HIGH SUCTION PRESSURE SHUT OFF
This is an energy saving feature which is normally offered as an extra cost option on competitive systems. It functions to prevent the pumps from operating at any time that the system inlet (supply) pressure is high enough to supply service needs without requiring a pressure boost. This is a standard design characteristic of the invention and is furnished on all systems. Function is quite simple and is performed by pressure with PSI FIGS. 1 and 2, (7). Since the inlet pressure will pass directly through all pumps and into the primary tank FIG. 1 (4) at any time that the inlet pressure is higher than the set point of pressure switch PSI FIGS. 1 and 2, (7) PSI will remain in the open position and the pumps will not be started. Service demands will be provided by the inlet pressure.
CONTROL OF SYSTEM HAVING VARIABLE INLET (SUCTION) PRESSURE AND NOT FURNISHED WITH PRESSURE REDUCING VALVES
When a water booster system must operate under conditions of having a variable inlet pressure, the minimum inlet pressure must be utilized as the base value in determining the set points for all of the pressure switches used for starting and sequencing the pumps. This is essential to prevent the pumps from failing to shut off under conditions of minimum inlet pressure. For installations wherein the inlet pressure fluctuates through a wide range of variation, efficiency of such systems can be improved by the addition of a differential pressure switch FIGS. 1 and 2, (14). The differential pressure switch functions to prevent the pumps from shutting off as a result of an increase in the inlet pressure. It maintains the number one pump in operation until such time as the primary tank pressure FIG. 1, (4) equals the combined pressure of the inlet pressure plus the set pressure of the differential pressure switch. In this manner, both the primary tank, FIG. 1, (4) and the secondary tank, FIG. 1, (5) will be charged to the maximum pressure attainable at the time at which the differential pressure switch opens to stop the number one pump and place the system into static mode of operation. Hydraulic connections of the differential pressure switch are to the suction manifold FIG. 1, (15) for the low pressure side and to the pressure sensing point of the primary tank FIG. 1, (51) for the high pressure side. The electrical power for the maintaining circuit to the number one pump is through the closed contacts of the differential pressure switch, FIG. 2, (14), through the closed M1 auxiliary starter contact, FIG. 2, (29) and then through the normal operating circuit for motor starter number one FIG. 2, (18) as previously described.
EXPANSION CAPABILITY
The operational description provided for staging additional pumps as in FIGS. 4 and 5 illustrates; The basic operational simplicity with which additional pumps may be controlled by applying the same principle of operation as the basic invention employs. This method of staging and controlling with a specific design pressure range, a virtually unlimited number of pumps without requiring complex relay or electronic circuitry is a unique advantage of the invention. The basic features derived by this means of control are retained throughout the full operational range of the system. Heretofore a five pump automated pump control system providing the standard design features of this system could only be undertaken by employing the highest state of the art technology utilizing costly and complex relay and electronic controlling devices. The cost of such control systems can far exceed the cost of the pumps. This is not a forseeable occurence with this method of control. There are varied methods in which additional pumps can be staged and sequenced into the system. Depending upon system design tolerances it is conceivable that as many as four or more pumps could be controlled by a single dynamic control tank. The method of alteration/sequencing the pumps to equalize operating hours is totally flexible. Any type of multi-pump sequencing device could be employed. In undertaking the design of this system, basic simplicity of control combined with highest reliability and minimum cost has been a foremost objective.
|
A multiple pump supply system having multiple pumps placed in parallel and having a plurality of reservoirs connected to acommon discharge line. The pumps are operated sequentially on demand sensed by a pressure sensor located at the mouth of the first reservoir and controlling a first pump. Multiple sensors located at the mouth of a second reservoir control the subsequent pumps sequentially.
| 4
|
TECHNICAL FIELD
This invention relates to various structural elements, such as poles for supporting electric power lines; and more particularly it relates to solid and hollow poles and other structural elements made of plastic materials that are reinforced in strength by filaments encased in the solid plastic of the pole or element and running lengthwise of the pole or element.
BACKGROUND OF THE INVENTION
The applicant has shown in U.S. Pat. Nos. 5,004,574 and 5,405,668 various structural shapes of plastic rods and tubes which are reinforced in strength by the presence of fibers or filaments running lengthwise and being encased in the plastic. Methods for making such items are also disclosed in these patents. Among the uses for such technology is the making of poles to replace wooden poles that are getting more costly as less wood is available for such uses. Wooden poles are subject to deterioration from the atmosphere and from being buried in the soil. Plastic materials can readily replace wooden poles in many, if not all uses, and it accordingly is the primary purpose of this invention to provide a method for preparing poles, beams or other structural load bearing elements from plastic materials. In order to reduce weight and cost it is preferred that such poles, beams or elements be made hollow; and in order to provide sufficient strength for minimum volumes, it is preferred that the plastic material be reinforced by fibers or filaments generally running lengthwise of the element so as to provide flexural strength. This invention is useful for structural cantilever members, e.g., in airplane wings, spars or the like; masts or poles of any size or shape, e.g., power poles for high tension electricity, poles for lights, fence poles and poles and beams for all sorts of building or construction supports.
BRIEF SUMMARY OF THE INVENTION
This invention relates to an article of manufacture and to a method for preparing that article. The article of manufacture is a tapered load-bearing structural member, such as a pole or beam with a large diameter end that may be buried in the ground or otherwise supported in a fixed manner or cantilevered out from a structure and a small diameter end that may be vertically above ground for supporting any of a variety of objects, e.g., power lines, telephone lines, illuminating lights or merely a wire fence. A preferred structural element is a pole made of two concentric, generally rigid sleeves separated by a space filled with a solid plastic material having dispersed therethrough reinforcing fibers or filaments running lengthwise of the pole and being present at a generally uniform density of filaments to resin at any transverse cross-section of the pole. The sleeves may be of any convenient thickness, depending on the overall size of the pole, e.g., 0.25-1.0 inch thick for a pole 6-40 feet tall. The core of plastic and dispersed reinforcing fibers or filaments may be 0.5 to 3.0 or more inches thick depending on the strength required in the pole and its dimensions. The diameter of the central hollow may vary with the specific design of the pole. Generally the materials employed for the sleeves are thermoplastic resins that may be readily extruded into hollow tubular forms and blow molded or rotationally molded into conical elements. The central core is generally made of a reactive resin, such as an amine-formaldehyde resin. The reinforcing fibers or filaments may be glass, metal, carbon, natural fibers or filaments or synthetic fibers or filaments. A particularly good combination employs polyvinyl chloride sleeves, polyester, epoxy or phenolic reactive resin in the core and glass fibers for reinforcements.
The hollow structural member of this invention may be made by a variation of the process of U.S. Pat. No. 5,004,574 in which preformed inner and outer sleeves are aligned so as to relatively move the sleeves with respect to each other, as by pulling the inner sleeve into the outer sleeve while filling the space between those sleeves with a resin in liquid form, and simultaneously pulling fibers or filaments into that circumferential space so as to extend throughout the length of the pole and thereafter capping the ends.
Another preferred structure of this invention is a solid tapered pole with only one sleeve which is an outer covering for a solid core of plastic material in which are dispersed lengthwise fibers or filaments.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a side elevation view of a long pole of this invention having a smooth tapering outside surface and a smooth tapering inside surface around a central tapering hollow;
FIG. 2 is a side elevational view of a long pole of this invention having a smooth tapering outside surface and a stepped tapering inside surface around a central tapering hollow;
FIG. 3 is a side elevational view of a long pole of this invention having a stepped, tapering outside surface and a smooth tapering inside surface around a central tapering hollow;
FIG. 4 is a side elevational view of a long pole of this invention having a stepped tapering outside surface and a stepped tapering inside surface around a central tapering hollow;
FIG. 5 is a side elevation of a long tapered pole of this invention which has a solid interior;
FIG. 6 is a schematic illustration of the beginning of a process of this invention whereby the small end of a hollow stepped tapering inside sleeve is being introduced into the large end of a hollow stepped tapering outside sleeve to be pulled into place as liquid resin and reinforcing filamentary material is introduced into the space between the outer and inner sleeves;
FIG. 7 is a schematic illustration of the middle of he process described above with respect to FIG. 6;
FIG. 8 is a schematic illustration of the end of the process depicted in FIGS. 6 and 7;
FIG. 9 is a longitudinal cross-section of a long hollow pole made by the process shown in FIGS. 6-8;
FIG. 10 is an enlarged transverse cross-section of the long hollow pole shown in FIG. 9;
FIG. 11 is a schematic illustration of a process of this invention similar to those shown in FIGS. 6-8 except that the product is a solid article;
FIG. 12 is a transverse cross-section of a solid pole, such as shown in FIG. 5 and made by the process at FIG. 11;
FIG. 13 is a longitudinal cross-section of the pole of FIG. 12;
FIG. 14 is illustration of the initial bundle of filaments saturated with resin being pulled into the tapered outer casing;
FIG. 15 is an illustration similar to FIG. 14 and showing additional filaments being carried by a looped filament at a successive length spaced from the forward small end of the casing; and
FIG. 16 is an illustration similar to FIG. 15 and showing spaced looped filaments carrying additional filament bundles into and along the length of the casing.
DETAILED DESCRIPTION OF THE INVENTION
The process and product of this invention are best understood by reference to the attached drawings which show preferred embodiments of this invention.
The drawings of FIGS. 1-4 show typical examples of the articles made according to this invention. There are shown four varieties of poles 51-54 that taper from a small end at 55 to a large end at 16 and each having a central hollow 38 extending the entire length of the pole. Each of these poles 51-54 in FIGS. 1-4 has at any transverse cross-section a circular external shape and a circular internal shape. Other shapes, however, are contemplated in accord with this invention. In some instances the surface (internal or external) may be smooth; and in other instances the surface may be stepped. "Stepped" herein means a series of cylindrical surfaces, each succeeding step being of a slightly smaller or larger diameter than the preceding step while the surface in any one step is a single diameter. In the instance of FIG. 5 where both inside and outside surfaces are stepped, it is preferred to offset the juncture 17 between adjoining steps in the interior surface from that similar juncture in the exterior surface so as to avoid any weakened locations in the pole. If there were no offset, the thickness of the pole wall might at each step be thinner than desired; and by offsetting that juncture so that the inside and outside steps do not occur at the same location, that potential weakness is avoided. "Stepped" herein also relates to shapes other than cylindrical.
There are shown here poles with circular cross-sections. It is to be understood, however, that this invention contemplates other shapes, such as described more fully in my U.S. Pat. No. 5,004,574 with respect to FIGS. 3-5 of such patent, e.g., triangular, rectangular, square, pentagonal, hexagonal, and the like. These shapes of outside skins or sleeves may be combined with similar inside shaped sleeves, or other dissimilar inside skins or sleeves, such as is shown by poles 52 and 53 in FIGS. 2 and 3 of this application. Other structures, such as masts, beams, spars, rods, tubes, etc. are encompassed in this invention.
The process of preparing the poles of FIGS. 1-4 is shown in FIGS. 6-8, and the pole made by this process is shown in FIGS. 9-10. In FIG. 6 there may be seen the general features of the manufacturing process which starts by positioning an inside generally rigid sleeve 19 and an outside generally rigid sleeve 18 along a common longitudinal axis which is an extension of the direction of cable 34 and supporting these sleeves (by means not shown) as they are telescoped together to make the final product as shown in FIGS. 9-10. The larger and smaller sleeves 18 and 19 are formed by ordinary extrusion methods which are not part of this invention. These sleeves may be of whatever thickness that is appropriate, probably from 0.25 to 1.0 or more inches in thickness, and are made from a suitable thermoplastic material, a preferred type being polyvinyl chloride. The larger sleeve 18 is positioned in a generally horizontal position, preferably tilted downward toward the small end (to the right in FIGS. 6-8) so that liquid reactive resin introduced inside the sleeve will gravitate toward the small end. The smaller sleeve 19 is aligned so as to enter inside the larger sleeve 18 and be pulled to align both ends and thereby produce a hollow tapered pole when the process is completed. The smaller end of the smaller sleeve 19 is fitted with a plug 32 having an eye 33 through which pulling cable 34 is threaded and wound onto drum 23 which can be driven like a windlass to wind up cable 34 on drum 23 as smaller sleeve 19 is pulled completely into larger sleeve 18. For the sake of simplicity no details are shown as to how to support sleeves 18 and 19 during this process, but it will be appreciated that such may be accomplished by movable belts, a plurality of freely rotatable drums or discs, or other more complicated means. There may also be a second plug 41 at the smaller end of larger sleeve 18 to prevent too much leakage of liquid reactive resin, if such a plug is needed; although the liquid reactive resin is quite viscous and will begin hardening sufficiently to minimize any such leakage and may obviate the need for second plug 41.
Mounted above the larger end 16 of sleeve 18 is a supply of liquid reactive resin 21 in reservoir 20 that empties into hopper 22 supported on frame 35 and drains through channels into the space between larger sleeve 18 and smaller sleeve 19 at the large end 16 of sleeve 18. That liquid reactive resin is fed slowly to match the slow forward movement (to the right in FIGS. 6-8) of smaller sleeve 19 into larger sleeve 18. Simultaneously there is introduced into that same space between sleeve 19 and sleeve 18 reinforcing filaments represented by 26 and 27. These filaments 26 and 27 are unwound from spools 24 and 25 and passed through pools 30 and 31 of liquid reactive resin 21, so as to wet the filament before it is immersed in resin 21 which fills the space between sleeves 18 and 19. Pools 30 and 31 may contain spools or pulleys 28 and 29 to assure that filaments 26 and 27 are totally immersed in pools 30 and 31 and totally wetted by the liquid resin therein. There are shown in FIGS. 6-8 only two spools 25 and 26 and their separate wetting pools 30 and 31, but it is to be understood that this process will include several other similar spools of filament and pools of wetting resin sufficient to introduce reinforcing filaments throughout the circumferential space 50 between sleeves 18 and 19 so as to produce the finished pole structure of FIGS. 9 and 10. As may be seen in FIG. 10 the cross-section shows outer sleeve 18 and inner sleeve 19 around a hollow center 38. The space 56 between sleeves 18 and 19 is filled with a solid reactive resin 21 through which are dispersed a large number of individual filaments such as 26 and 27 running the entire length of the pole and after solidifying form a reinforced core 39. It is important for this invention that the tapered structural and load bearing article have more filaments in the larger end than in the smaller end so that the density of filaments at any cross-section of the article will be generally equal and preferably substantially equal to provide uniform flexural strength in any direction at respective cross-sections. The "reactive resin" as used herein is preferably a liquid thermoplastic resin which is used as a liquid and sets to a hard solid. Such materials are technically known as polyester, epoxy, phenolic, or urea resins which solidify from a liquid form to a hard insoluble final product. Heat is frequently applied to accelerate the hardening or setting of the resin.
FIG. 7 shows the process as started at FIG. 6 and which has progressed until small end of inner sleeve 19 with plug 32 is about half way into larger sleeve 18. FIG. 8 shows the process completed when the smaller ends of both sleeves 18 and 19 are aligned. The introduction of resin 21 is then stopped, the feeding of filaments from reels 24 and 25 is stopped, and windlass 23 is stopped. As soon as the resin in the space 56 between inner sleeve 19 and outer sleeve 18 hardens into a solid core 39, plugs 32 and 41 can be removed and the article will be that shown (in larger scale) in FIGS. 9 and 10. Generally the proportion of filament to resin in the space 39 between sleeves 18 and 19 will be about 50-60% by weight of filament and 40-50% by weight of resin for maximum flexural strength. Other ratios of filament-to-resin are generally operable for other purposes. For a 40-foot pole used as a support for power lines the outer diameter at the larger end of the outer sleeve 18 might be 5"-10" and the inner diameter of the inner sleeve 19 at the larger end might be 4"-6" leaving a space 56 between sleeves 18 and 19 of 1"-4" thick to be filled with reactive resin and filaments in a ratio of 50-75% filament and 50-25% resin by weight.
It should be noted that it may be advantageous to employ end caps 40 and 42 (see FIG. 9 herein) over the ends of such poles as shown in FIG. 10 of U.S. Pat. No. 5,004,574 to protect the resin-and-filament structure in the space between outer sleeve 18 and inner sleeve 19 from the damaging effects of weather, air, moisture, sunshine, etc. End caps 40 and 42 are shown over the ends of the finished pole in FIG. 9 of the attached drawings. Such end caps 40 and 42 are preferably sealed by adhesives or other means to outside sleeve 18 so as to prevent moisture or other destructive materials from contacting core 39. The end caps 40 may be generally flat or slightly convex with a single surrounding flange 43. The end cap 42 may have a hollow 46 generally medially with a pair of spaced surrounding flanges 44 and 45 lying against and sealed to sleeves 19 and 18 respectively.
FIG. 11 shows a process for preparing the solid interior pole of FIG. 5. This pole has only one sleeve, that being an outer sleeve, that being an outer sleeve 18 which is filled with a solid core 48 of reactive resin 21 and lengthwise filaments 36, 37 dispersed throughout the reactive resin. The process of manufacturing this solid pole is similar to that described above with respect to FIGS. 6-8 except that there is no inner sleeve nor a central hollow. The outer sleeve 18 is positioned in a generally horizontal position with plug 32 attached through eye 33 to windlass 23 by cable 34. Plug 32 has a plurality of reinforcing fibers, such as 36 and 37, attached thereto and these filaments are pulled from large end 16 to small end 55 of the sleeve 18 as it is filled with reactive resin 21 fed from reservoir 20 into hopper 22 supported on frame 35 and thence into large end 16 of sleeve 18 at large end 16. When this process is completed the cross-section of sleeve 18 filled with a solid core 48 of resin 21 and filaments 36, 37 is that shown in FIG. 12 as a transverse cross-section and in FIG. 13 as a longitudinal cross-section also showing end caps 47 similar to end cap 40 of FIG. 9.
Any convenient method may be used in introducing an increasing number of reinforcing filaments into space 56 between inner sleeve 19 and outer sleeve 18 as the process proceeds from inserting small end 55 of inner sleeve 19 into large end 16 of sleeve 18 to the end of the process when sleeve 19 is completely inserted into sleeve 18. One preferred method is depicted in FIGS. 14-16 and includes tying at several spaced locations along the first reinforcing filaments 26, 27 introduced into space 56 a loop 58 of filament tied to, for example, filaments 26 and 27 and others, to which are tied bundles of other filaments 59 that will extend from that loop 58 to the large end of sleeves 18 when the process is completed. the next bundle of filaments 60 tied to successive loop 61 are distributed circumferentially within sleeve 18 so as to fill that space 56 with reinforcing filaments. Additional bundles of filaments 62 are similarly introduced by being tied to successive loops 63 farther along the length of sleeve 18 (or sleeves 18 and 19) as they are pulled together in the process. In this way there are more reinforcing filaments at the large end of space 56 than at the small end of space 56 to provide greater flexural strength at the large end where it may be fixed, as with a high tension electric pole or the like. Ideally, the filaments will be distributed at any cross-section such that the density thereof in the core 39 or core 48 will be uniform.
In the event that cross-arms are needed for the poles of this invention the process described herein can readily be employed to prepare nontapered lengths for such uses, and such arms could be equipped with end caps as described above, in order to prevent any rapid deterioration of the core due to weathering in the atmosphere. Such cross-arms may have an upper surface to minimize the accumulation of snow or ice thereon.
While the invention has been described with respect to certain specific embodiments, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.
|
A tapered pole for supporting electric power lines, telephone lines, or an electric lamp which includes two tapered plastic, generally rigid sleeves positioned concentric to a longitudinal axis with the space between the sleeves being filled with a plurality of longitudinal generally continuous filaments encased in a solid plastic material; and a method of preparing such a pole by pushing or pulling the inside sleeve into an outside sleeve while filling the space between the sleeves with a liquid plastic material with reinforcing fibers or filaments being positioned into the space as movement occurs and the liquid plastic fills that space. The fibers are generally continuous and the per inch distribution between the ends of the pole are generally equal. End caps seal the ends against the weather elements.
| 4
|
This invention relates generally to beverage dispensing machines and more particularly to an ice bank control system used in beverage dispensing machines.
The invention is particularly applicable to and will be described with specific reference to an improved sensing probe having particular application to controlling formation of ice in the ice water tank of a beverage dispensing system. However, those skilled in the art will recognize that the invention may have broader application and could be used to control the formation of ice or solids of any liquid bath in which the liquid undergoes a phase change which is to be controlled.
INCORPORATION BY REFERENCE
The following United States patents are incorporated by reference herein and made a part hereof so that details of beverage dispensing machines conventionally known in the art and also details of conventional ice bank controls used in such machines need not be set forth in detail herein:
U.S. Pat. No. 5,022,233 issued Jun. 11, 1991 entitled "Ice Bank Control system for Beverage Dispenser".
U.S. Pat. No. 4,823,556 issued Apr. 25, 1989 entitled "Electronic Ice Bank Control".
U.S. Pat. No. 4,008,832 issued Feb. 22, 1977 entitled "Three Drink Gravity Dispenser for Cool Beverages"
U.S. Pat. No. 4,497,179 issued Feb. 5, 1985 entitled "Ice Bank Control System for Beverage Dispenser"
The patents incorporated by reference herein do not form part of the present invention.
BACKGROUND OF THE INVENTION
Beverage dispensing machines conventionally employ an ice water tank in which the evaporator coil of a refrigeration unit is placed as well as beverage tubing coils through which beverage product (syrup, carbonated water and water) flows. The temperature of the ice water tank is ideally maintained at 32° F. to chill the water and syrup when dispensed through the machine's dispensing valve. Chilling of the beverage product occurs by conductive heat transfer across the tubing wall. To satisfy peak demand, the refrigeration unit is operated to build an ice bank about the evaporator coils so that the ice will provide an additional heat sink or cold storage to compensate for increased flow of the warmer fluids in the water and syrup coils. Chilling of the beverage product causes some of the ice to melt. The compressor of the refrigeration unit is then operated to replenish the ice.
The ice bank size must be controlled within a specified size range. For example, if the ice bank is too small, there may not be enough cold storage to satisfy periods of high cooling demand. However, if the ice bank becomes too large, it may grow into the beverage product coils causing the beverage product to freeze and rendering the beverage dispenser inoperable.
An ice bank control is conventionally used to cycle the refrigeration compressor and maintain the ice bank within an acceptable size range. Conventional ice bank controls use a sensor immersed at a preset location in the ice water tank to detect the presence of ice. As ice surrounds the sensor, the control detecting the presence of ice switches the compressor off. As the ice gradually melts away from the sensor, the control no longer detects ice and switches the compressor on. The cycle repeats itself indefinitely.
Two types of ice bank controls, mechanical and electronic, are in conventional use. The most popular are the mechanical controls which have been used for several decades. These controls typically employ a sensing bulb immersed in the ice water tank. The bulb is filled with water which itself freezes when surrounded by ice. When the bulb water freezes, the water (now ice) expands and pushes against a rubber diaphragm constructed in the sensing bulb. The diaphragm in turn pushes against a non-freezing ethylene glycol solution and pressure developed in the glycol solution is transmitted via a capillary tube to a piston assembly. The piston assembly, located outside the ice water tank, expands a rubber cup to push a piston against a spring lever mechanism which in turn actuates an electrical switch to deenergize the compressor. As the ice bank melts away from the sensing bulb, the reverse process occurs and the switch closes to actuate the compressor.
The mechanical control has been popular for many years because of its low cost and simplicity of operation. However, the control is very unreliable due to manufacturing variances and simply inherent mechanical wear. For example, faulty diaphragms or seals, leaking glycol, sticking pistons and improperly formed levers often cause intermittent compressor cut-in or cut-out. In a worst case failure mode, the mechanical control may cause the compressor to run continuously. This can cause the entire ice water tank to freeze up and extensively damage the beverage dispenser.
Electronic ice bank controls have been developed in recent years to provide increased reliability and this invention relates to an electronic control. Electronic control systems use an electrode assembly immersed in the ice water tank to sense the presence of ice. In its basic application, a low alternating current voltage (typically 9 volts) is applied to one pole of the electrode. Some electronic controls use pulsed direct current. Another electric pole is referenced to ground. Ice having a much higher electrical resistance than water, can be detected by comparison of electrical resistance across the electrode poles. A control board electrically connected to the electrode assembly is used to make the resistance comparisons and provide output switching action to operate the compressor.
U.S. Pat. Nos. 4,008,832 and 4,497,179 illustrate conventional electronic controls in which two probes are placed in the ice water tank in closely spaced alignment with the evaporator coil. The probe furthest from the evaporator senses water and the probe positioned closest to the evaporator senses ice. The compressor is cycled on when the ice probe detects water and off when the water probe detects ice. .While such arrangements as disclosed in the '832 and '179 patents have proven more reliable than the mechanical sensor arrangement described above, they are susceptible to failures in that contaminants, such as syrup within the ice water tank, can lower the freezing point of the tank. Water in the water coil then freezes rendering the dispenser inoperable. Still further, as a function of time, deposits from the ice water tank, resulting from evaporation for example, varies the resistivity of the probes adversely affecting their readings. In this connection, U.S. Pat. No. 4,823,556 teaches the use of four separate probes, two of which generate a resistance signal depending on the actual ice water tank conditions which then serves as the basis upon which ice and water probe signals are compared against to cycle the compressor off and on. The assumption is that all the probes will uniformly degrade so that the comparison will be viable. U.S. Pat. No. 5,022,233 offers another solution to the drift and/or probe degradation problem. In the '233 patent only one probe, precisely positioned where the desired ice-water interface is desired to occur, is used and the circuitry for shutting off and on the compressor includes a programmable microprocessor that compares the readings obtained over time and automatically correlates or adjusts them to the desired beta curve to account for drift.
In summary, a number of problems arise in conventional, electronic ice bank control systems which can be attributed to the fact that the sensor or the probe is in contact with the contents of the ice water tank. As noted, water deposits lead to contamination of the probe affecting its readings. Impurities such as syrup in the tank adversely affects the controls by lowering the freezing temperature of the tank. Because the sensor must be immersed in the tank an electrical short between the lead wires, caused by faulty insulation, can result. Stray voltage in the ice water tank can be transmitted to the electrodes. The prior art teaches to address the problems by using circuitry and/or software downstream of the probe in the control circuit. This approach increases the price of a system which is already more expensive than the mechanically equivalent system discussed above. Fundamentally though, the prior art reacts to the problem instead of addressing the problem. Should the control circuit be designed to not accurately respond to the problem encountered by the probe, or worse yet, fail to address the specific malfunction of the probe, the system will fail.
In addition to this inherent problem present in the electronic control systems of the prior art, special steps must be taken by means of specially designed bracket/spacers to accurately place the probe in desired spaced and orientation relationship to the evaporator coil. This necessitates disassembly or removal of the refrigeration deck of the beverage dispenser to gain access to the evaporator coils. The bracket has to be designed and applied in such a manner that the sensor doesn't move while ice grows and dissipates about it. When several sensors are used, typically encased in a bulb attached to the evaporator coil, care must be taken to assure that the sensors extend on a radial line from the center of the evaporator tubing. Such requirements make it difficult and/or expensive to retrofit mechanically equipped ice bank control beverage dispensers with electronic ice bank controls. It also makes replacing failed sensors difficult.
SUMMARY OF THE INVENTION
Accordingly it is a principal object of the invention to provide an electronic ice bank control in a beverage dispensing system which is consistently reliable because it avoids the contamination or degradation problems afflicting prior art systems resulting from exposure of the sensor to the contents of the ice water tank.
This object along with other features of the invention is achieved in a conventional beverage dispenser which includes at least one dispensing valve for dispensing a beverage, an ice water tank, at least one beverage coil carrying at least one beverage constituent in fluid communication with the dispensing valve and extending at least partially within the ice water tank, and a mechanical refrigeration unit. The refrigeration unit includes a compressor, an evaporator coil within the ice water tank, an ice sensing probe within the ice water tank for generating electrical signals to indicate the presence of ice and a control circuit or mechanism including a first circuit for cycling the compressor off and on in response to the probe's electrical signals. The ice sensing probe of the ice bank control system has a sealed tubular member containing a water well therein, a signal electrode extending into the water well and a ground electrode within the water well whereby the probe senses the presence of ice at a precise point within the tank while being insulated from contact with the contents of the ice water tank thus avoiding all the problems of the prior art system resulting from or attributed to contact with the contents of the ice water tank.
In accordance with another important feature of the invention, the tubular member is a cylindrical tube having a closed bottom end situated within the ice water tank and containing the water well and an open top end outside the ice water tank, and a cap closing the top end of the cylindrical tube and hermetically sealing the cylindrical tube whereby the cylindrical tube isolates the water well from the ice water tank while maintaining thermal conductive contact with the contents thereof.
In accordance with yet another important aspect of the invention, the control system additionally includes a thermistor in contact with the water well and the control mechanism or circuit further includes a second circuit effective when sensing an electrical signal from the thermistor indicative of a lower temperature than that sensed by the electrode to stop the compressor thus providing a fail safe mechanism preventing excessive ice formation within the ice water tank should a failure preventing the first circuit from cycling the compressor off occur for any reason.
In accordance with still yet another important feature of the invention, the dispenser has a refrigeration deck covering the ice water tank and an opening is provided within the refrigeration deck allowing the cylindrical tube to extend therethrough in spaced relationship to the evaporator coil. A mounting arrangement adjacent the top end of the cylindrical tube is provided for securing the cylindrical tube to the deck whereby the probe can be retrofitted to existing beverage dispensers without dismantling the dispenser or requiring that the probe be positioned with a precise orientation of the electrodes with respect to the evaporator coil.
It is thus an object of the invention to provide a reliable, electronic ice bank control system by use of a probe which is isolated from the contents of the ice water tank while maintaining thermal contact therewith.
It is another object of the invention to provide an electronic ice bank control system for a beverage dispenser which has a fail safe mode to prevent excessive ice formation in the ice water tank.
It is yet another object of the invention to provide an electronic ice bank control system which can be easily applied and is ideally suitable for retrofit installation to beverage dispensers.
Still another object of the invention is to provide an improved ice bank control system which uses simple control circuitry to cycle the compressor off and on.
Still yet another object of the invention is to provide an ice bank control system for a beverage dispenser which is relatively inexpensive.
Still another object of the invention is to provide a beverage dispenser ice bank control system which is more responsive and better able to control the size of the ice bank of the ice water tank in the beverage dispenser than conventional systems.
Another important object of the invention is to provide an ice bank electronic control system which has a long life and greatly improved reliability.
These and other objects of the invention will become apparent to those skilled in the art upon reading and understanding the Detailed Description of the Invention set forth below together with the drawings described below.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take form in certain parts and arrangement of parts, preferred and alternative embodiments of which will be described in detail in this specifications and illustrated in the accompanying drawings which form a part hereof and wherein:
FIG. 1 is a schematic elevational view of a conventional beverage dispenser which also shows the dispenser and dispenser valve taken from another plane view of the dispenser;
FIG. 2A is a partial elevational view of a prior art probe conventionally mounted to the evaporator coil of a refrigeration unit used in a beverage dispenser;
FIG. 2B is a schematic construction of the alignment of the prior art probe shown in FIG. 2A viewed from the top;
FIG. 3 is a schematic representation of the preferred embodiment of the ice bank control of the present invention;
FIG. 4 is a schematic view similar to FIG. 3 but of an alternative embodiment of the present invention;
FIG. 5 is a schematic elevational view showing the probe of the present invention applied to an ice water tank of a beverage dispenser; and,
FIG. 6 is a view similar to FIG. 4 showing a third embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings wherein the showings are for the purpose of illustrating a preferred embodiment as well as alternative embodiments of the invention, there is shown in FIG. 1 a conventional beverage dispensing machine or simply beverage dispenser 10 having a housing including an ice water tank 12 insulated as at reference numeral 13 and covered by a removable shroud 14. Ice water tank contains an ice water bath, the top surface of which is indicated by reference numeral 15 in FIG. 1. Covering the top of ice water tank 12 is a refrigeration deck 16 upon which is mounted a mechanical refrigeration unit 17.
Refrigeration unit 17 conventionally includes a compressor driven by an electric motor (motor and compressor indicated schematically by reference number 18) which conventionally operates to discharge a refrigerant through an expansion valve or capillary tube into an evaporator coil 20 positioned within ice water tank 12. Conventionally secured to evaporator coil 20 is a conventional ice sensor 21 having a lead 22 extending through the top surface of the ice water bath 15 and connected to an ice bank control 23 mounted within a control housing 24 secured to refrigeration deck 16. Conventional sensor 21 and ice bank control 23 operate in a known manner to control the size of an ice bank, the outer boundary of which is shown by the dot-dash line indicated by reference numeral 25.
Also positioned within ice water bath 15 are beverage product coils. A syrup coil is shown by reference numeral 27 and a carbonated water coil is shown by reference numeral 28. Beverage product passing through syrup and water coils 27, 28 is chilled by thermal conduction with ice water bath 15 and transmitted through beverage lines 29, 30 to a conventional dispensing valve 32 which mixes and discharges the drink through nozzle 34.
Also positioned within ice water tank 12 is an agitator 35 driven by electric motor 36. It is known to control the operation of agitator 35 (on-off) through ice bank control 23 in accordance with the presence or absence of ice sensed by conventional sensor 21. It is similarly contemplated to likewise control agitator through the ice bank control of the present invention.
Everything described thus far is conventional and prior art to the present invention except for the improved combination resulting therefrom.
Referring now to FIGS. 2A and 2B, there is shown a conventional electronic ice bank control sensor 21 mounted within a sensor housing 40 and having three electrodes, namely an ice electrode 41 extending along axis 42, a water electrode 43 extending along axis 44 and a ground electrode 44 extending along axis 46. Conventional ice bank control 23 cycles compressor 18 off and on to control the size of ice bank 25 within the positions of ice electrode 41 and water electrode 43. That is, with compressor 18 off, heat transfer between beverage coils 27, 28 raise the temperature of ice water bath 15 reducing the size of ice bank 25 as the ice melts. When ice bank 25 shrinks to a dimension exposing ice electrode 41 to water, the resistance between the ice electrode 41 and the ground electrode 45 changes and ice bank control 23 senses the change to cycle compressor 18 on. Refrigerant expands within evaporator coil 20 lowering its temperature to about 15° F. and ice begins again to build around the evaporator coil 20 within ice water bath 15. When ice bank 25 grows and reaches water electrode 43, the resistance between the water electrode 43 and the ground electrode 45 changes and conventional ice bank control 23 turns the compressor off. The cycle repeats itself indefinitely. It should also be noted that ground electrode 45 is furthest removed from evaporator coil 20 and is always exposed to water in ice bath 15. This arrangement, when operating as described inherently provides a dead or null zone during the time the ice grows and contracts between the ice and water electrodes 41, 43 which in turn prevents compressor 18 from rapidly cycling off and on. Thus when compressor 18 is on, it is on for a sufficient time length to permit steady state, efficient refrigeration operation to occur which won't happen if compressor 18 is subject to quick on-off cycles.
Conventional electronic ice bank control sensors 21 are rigidly and firmly mounted to evaporator coil 20 by any number of spacer/mounting arrangements such as shown by reference numeral 48 in FIG. 2A. As can be readily seen in FIG. 2A, ice bank 25 is maintained at its maximum dimension so long as space/mounting arrangement 48 maintains electrode centerline 42, 44 and 46 parallel with evaporator coil centerline 49. Should the spacer/mounting arrangement 48 permit sensor housing 40 to pivot about evaporator coil 12 in the plane of FIG. 2A the ice bank dimension will be smaller than shown. FIG. 2B shows that the same problem can occur in a plane orthogonal to the plane of FIG. 2A. It is possible over time, because the ice bank is growing and contracting to move the position and/or attitude of sensor housing 40 and thus adversely affect the cooling capacity of ice water tank 15.
The conventional electronic ice bank control system now described in some detail is subject to the defects discussed above besides those just described relating to its installation. The sensor leads, while insulated, extend from within ice water bath 15 to control housing 24. Should the insulation be defective either when made, installed or during use, sporadic failures will occur. As noted, should syrup or other substances leak into or contaminate ice water bath 15, the freezing point of the resultant mixture will be lowered with the result that the electronic control will drive the temperature of ice water bath below 32° F. When this happens water coil 28 freezes water flowing through the coil. The electrolyte composition in ice water bath 15 is unpredictable and could cause erroneous readings of conventional sensors 21 triggering failures of ice bank control 23. Similarly stray voltages sporadically appearing in ice water bath 15 could trigger the same result. As noted above chemical deposits resulting from evaporation and other events can also adversely affect the resistance readings of conventional temperature sensors 21. Also, as noted above, prior art approaches to this problem have been to provide additional circuitry or sophisticated electronics in ice bank control 23 to interpret the resistance readings in a "smart" manner to either discard or modify the reading to that which the "smart" logic dictates.
The present invention will be shown to overcome all such problems and reference should be had first to FIG. 4 which, while an alternative embodiment, nevertheless discloses the underlying principle of the invention. There is shown in FIG. 4 a sensing probe 50 (referred to as "probe" to conveniently distinguish from the prior art devices discussed above which have been referred to as "sensor") having a tubular member 52 with a closed bottom end 53 and an open top end 54. In the alternative embodiment of FIG. 4, tubular member 52 is electrically conductive and is preferably metal, preferably copper. In all embodiments, tubular member 52 is preferably cylindrical. When tubular member 52 is metal, it is preferably electrically insulated from ice water bath 15 by a coating or encapsulation 55 of plastic. Co-incident with longitudinal centerline 57 of tubular member 52 or coaxially positioned within tubular member 52 is an electrically conductive electrode 58. Electrode 58 is accurately positioned within tubular member 52 by being inserted into dielectric cylindrical bushings 60 (rubber based, neoprene or plastic) having a central opening 61 snugly receiving the electrode and a dielectric, plastic end cap 63. Plastic end cap 63 has bottom end 64 and an annular shoulder 65 which abuts the edge surface of open end 54 of electrode 58 as well as a central opening 67 through which electrode 58 extends. As noted electrode 58 is positioned within bushings 60 and extends a precise distance from bottom end 64 of cap 63. When the electrode assembly is fitted into tubular member 52, bottom end 59 of electrode 58 will be positioned a precise fixed distance from bottom end 53 of tubular member 52. Before electrode 58, bushings 60 and end cap 63 are fitted into tubular member 52 a quantity of water is placed into the bottom of tubular member 52 filling tube member 52 to a fixed height shown as letter H in FIG. 4. This water comprises a water well providing an electrically conductive path between electrode 58 and tubular member 52. Importantly the water is distilled and treated with a desired concentration of electrolyte so that the water has desired electrical characteristics producing desired resistance to temperature characteristics for ice bank probe 50. When the electrode assembly as defined is inserted into tubular member 52 electrode 58 is precisely positioned within water well 70 and cap 63 is thoroughly sealed by an appropriate glue such as epoxy to tubular member 52 (as well as sealing cap opening 67) sufficient to establish an air or hermetic seal of tubular member 58 preventing any contamination or degradation of water well 70.
A ground wire 71 is soldered to tubular member 52 and an electrode wire 72 is soldered to electrode 58. Ground and electrode wires 71, 72 are plumbed into an electrical control board 74 which is functionally equivalent to prior art ice bank control 23 and employs conventional circuits similar to those used in prior art ice bank controls to measure the resistance readings generated by probe 50 and cycle compressor 18 on and off in response to such readings.
Line voltage i.e. (120 v. AC) is supplied at L1 and L2 to electrical control board 74 and switched on and off to compressor 18 via lines 76, 77 by means of an electrically powered relay 78 which in turn is actuated by a control circuit 80. The control circuit 80 senses resistance changes of probe 50 via leads 72, 71. A voltage conditioning circuit 81 provides a low AC voltage supply (typically 6-8 volts) through control circuit 80 to electrode 58 and similarly provides a voltage supply for biasing control circuit 80. Grounding may be provided as desired. "Ground" is used herein generally to mean a signal reference point. Control circuit 80 establishes the level of resistance between electrode 58 and tubular member 52 (when metallic) through leads 71-72. A "low" resistance indicates the presence of water in water well 70 and a "high" resistance establishes the presence of ice in water well 70. When a low resistance is sensed, control circuit 80 actuates relay 78 to close the switch and power compressor 18. When a high resistance is sensed, control circuit 80 deenergizes power relay 78 and opens the switch to shut off compressor 18. The only moving part in the system is power relay 76. With electrode 58 centered, as is preferred, the sensing electrodes are axially symmetrical. The orientation of the probe is not critical.
FIG. 5 illustrates ice bank probe 50 applied to tank 12. Tubular member 52 including plastic encapsulation 55 extends beyond ice water bath 15 through refrigeration deck 16 so that electrode leads 72 and 71 do not extend through ice water bath 15 and are thus not subject to the lead wire failures attributed to ice water bath 15 which afflicts prior art sensors. Ice bank probe 50 is positioned so that well water 70 is at any desired distance from evaporator coil 20 whereat the boundary of ice bank 25 is desired. Only one probe 50 need be used. Well water 70 is in direct thermal contact with the contents of ice water bath 15 by conduction through tubular member 52 (and plastic encapsulation 55) and conduction is uniform from ice water bath 15 to well water 70. At the same time well water is isolated from direct as well as electrical contact with ice water bath 15. Sediments and foreign contaminants will not affect probe 50 since well water 70 is shielded therefrom and it is not likely that such contaminants will adversely affect thermal conductivity between well water 70 and ice water bath 15. Stray voltages within ice water bath will not adversely affect probe 50 because of plastic encapsulation 55. Importantly, should the ice water bath 15 become contaminated and its freezing point drop below 32° F., the probe 50 will continue to maintain the ice water bath at 32° F. At this temperature, probe 50 will detect the presence of ice in well water 70 even though the water bath has not frozen to form an ice bank. Thus freeze up of water within water coil 28 will not occur.
Importantly the problem discussed with the prior art with reference to FIGS. 2A and 2B does not exist with probe 50. This is because water well 70 is essentially a point source. Radial orientation about longitudinal axis 57 does not affect the ability of ice bank probe 50 to accurately detect the presence of water and ice within a well member 70. Because of this feature, inherent in the design of probe 50, the probe can be applied to ice water tank 12 by simply fastening the top end of tubular member 52 to refrigeration deck 16 without consideration to radial orientation about its longitudinal axis 57. A hole 84 is simply drilled into refrigeration deck 16 and probe dropped through a selected vertical distance and secured at its top to refrigeration deck 16. No tie with evaporator coil 20 is necessary. Retrofit application of probe 50 to existing beverage dispensers 10 is easy.
It is preferred that the position of the probe 50 within the ice water bath 15 be fixed with respect to distance from the evaporator coil 20. This can be accomplished by sliding the probe 50 into a ring or tube which is fixed to the evaporator coil 20. This precisely fixes the probe's distance from the evaporator and assures optimal ice bank size control. The radial orientation of the probe about longitudinal axis 57 is not critical once its distance from the evaporator is established.
The probe 50 may be mounted to the refrigeration deck 16 near its top end. A collar 85 having a set screw can be applied to the probe 50. The collar rests on the deck 16 and the set screw holds the probe in place. The collar 85 also has a portion of reduced diameter 84 which sits in the opening in the deck. Other mounting arrangements will suggest themselves to those skilled in the art.
Another embodiment of the present invention is shown in FIG. 3 and like reference numbers will be used to describe the same parts and components used with reference to FIGS. 4 through 6B. In the preferred embodiment, probe 50 has a dielectric tubular member 52. The metallic tubular member 52 and plastic encapsulation 55 shown in FIG. 4 has been replaced by a plastic tubular member 52 and an insulated second electrode 93 extending into water well 70 and connected to a second lead 71. The second electrode has an exposed tip 92 directly below the tip 59 of the first electrode 58. The remainder of the second electrode 93 is covered with insulation, such as a plastic coating 97. This arrangement materially simplifies and reduces the cost of probe 50. Control circuit 80 is functionally the same as that shown in FIG. 3. In addition, a time delay circuit 94 (having a delay of, for example 4 minutes)is added to control circuit 80. The time delay circuit 94 keeps the relay 78 closed for a minimum period of time at each actuation. This prevents damage to the compressor.
A fail safe control feature takes the form of thermistor 95 (or a resistive temperature device, i.e., RTD) having a sensing element 96 potted within or on the probe preferably positioned at the bottom of water well 70. Leads 98, 99 for thermistor sensing element 96 are threaded through additional openings in bushings 60 and end cap 63 and connected to a fail safe control circuit 100 on control circuit board 74. Fail safe control circuit 100 is similar to control circuit 80 but does not employ any time delay circuit so that it is instantly activated. Fail safe control circuit 100 operates independently of control circuit 80 and is set to deenergize power relay 78 when the temperature of ice formed in water well 70 reaches a preset level, typically 20° F. Should there be a failure for whatever reason in electrode 58, second electrode 93 or first control circuit 80 which causes compressor 18 to remain on and build excessive ice, thermistor 95 will sense abnormally low temperature and override control circuit 80 and shut off compressor 18. The thermistor 95 exhibits a precise resistance to temperature relationship and therefore small resistance changes at the lower temperature, i.e., 20° F. will accurately and repeatedly occur. The fail safe control circuit 100 can set a specific resistance value correlated to a specific ice temperature within the water well and shut off the compressor at that temperature.
A third embodiment of the invention is shown in FIG. 6. The embodiment of FIG. 6 is identical to that of FIG. 3 except for the arrangement of the first and second electrodes. The first electrode 58 is a straight rod. An insulating tube 97 surrounds the first electrode 58. The second electrode 93 surrounds the insulating tube 97. The electrodes 58, 93 are fabricated from stainless steel to provide long term chemical stability in the probe 50. The first electrode 58 extends beyond both ends of the insulating tube 97. The insulating tube 97 extends beyond both ends of the second electrode 93. The second electrode 93 is provided with crimps 101 to maintain the electrode structure. The spacing between the tip 59 of the first electrode 58 and the tip 92 of the second electrode 93 is uniform about the axis of the probes. This embodiment is preferred as it eases manufacturing. The electrodes are assembled, crimped and placed more easily and accurately than in the other embodiments.
It is not necessary to use extensive circuitry which may store probe readings over time, compare the reading to obtain rate of change and contrast such readings to look-up tables stored in memory, etc. because of probe reading variations which would otherwise occur in conventional sensors. Because probe 50 can accurately detect minute resistance changes due to phase changes from ice to water and vice versa, a variety of sophisticated control techniques can be applied in electrical control board 74 which, in turn, can control the rate of growth and propagation of ice bank 25. The scope of this invention contemplates such applications.
The invention has been explained with reference to a preferred and. alternative embodiments. Modifications and alterations will occur to those skilled in the art upon reading and understanding the Detailed Description of the invention set forth above. For example end cap 63 could have a thermal insulation barrier applied to its end surface to make sure that ambient temperature does not adversely affect the temperature of well water 70. Two probes 50 could be utilized in a system if desired especially if the system is used to control ice growth at specific locations in ice water tank 15. Microprocessor controls could be utilized in electrical control board 74. It is intended to include all such modifications and alterations insofar as they come within the scope of the present invention.
|
An ice bank control for use in controlling the size of an ice bank in an ice water tank in a beverage dispenser utilizes an especially constructed probe having a sealed tubular member containing an electrolyte treated water well therein. An electrode extends into the water well and a ground is in contact with the water well so that the probe senses the existence of ice at a point within the tank while the tubular member insulates the electrode and ground from contact, electrical and physical, with the contents of the ice water tank.
| 5
|
RELATED APPLICATIONS
This application claims the benefit of Provisional Patent Application Ser. No. 60/154,057, filed Sep. 16, 1999 and Provisional Patent Application Ser. No. 60/157,811, filed Oct. 4, 1999.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method of and means for raising both the base rim and the cover of a manhole, catch basin, or other cast structure surrounded by pavement. The geometry of the rim and cover permit the use of a one-piece adapter which is itself cast entirely of the same material as the rim and cover. Further, the adapter allows the rim and cover elevation to be quickly raised by an amount less than the thickness of the cover, without requiring the removal of the surrounding pavement.
2. The Prior Art
Castings in newly paved areas ordinarily have rim elevations equal to the finished elevation of the pavement adjacent to the structure. If the pavement includes a bituminous section, the final lift of pavement (the wearing course) may not be installed for a year or more. During this time, castings which are in the bituminous pavement are left high to accommodate the ultimate placement of the wearing course. Such castings constitute an obstacle to pedestrian and vehicular traffic. Further, the lip created by the raised casting obstructs street scraping and cleaning operations as well as snow plowing, and impedes storm water drainage if the structure is part of the storm system.
One method of renovating the surface of a road is to place a bituminous overlay over the existing paving. Unless the overlay is thicker than the respective covers of structures within the overlay, the existing pavement must be removed from around the structure to allow the rim and cover elevation to be raised with shims. The adjusted structure elevation will then accommodate the placement of the overlay. Pavement that was removed to facilitate placement of the shims is replaced prior to placement of the overlay, which then serves as a new wearing course. This process is both time-consuming and costly, and causes additional congestion and potential for liability for workers renovating the road and for drivers frequenting the road.
An alternate method of renovating the surface of a road consists of removing the top layer of the road's surface and replacing the top layer with a new bituminous wearing course. The removal of the top layer of paving can be accomplished by milling the road's surface, but paving immediately adjacent to the structure requires hand work to remove. This process also involves extra time, additional expense, and increases traffic congestion and potential for liability.
In an effort to diminish such traffic congestion and potential for liability, and at the same time to reduce paving budgets, some municipalities have begun to use adapters which incorporate relatively thin steel segments. Alternately, the municipality or developer simply directs the paver to taper the overlay to meet the rim of the structure at its original grade.
The thin steel segments allow a method of quickly raising rim elevations a minimal amount, but introduce possible problems with regard to structural strength, access, and corrosion resistance.
The structural strength of the new adapters which incorporate thin steel segments is suspect, given the pounding the structure is subject to while the asphalt overlay is being placed, and impacting by snow plows and vehicle traffic. The adapter may not fail entirely, but may warp sufficiently to make removal and replacement of the cover problematic. Many such adapters require the use of protruding setscrews to secure the adapter to the rim below. The setscrews reduce the effective open area of the casting, and can be the cause of injury or damage to personnel or equipment entering or exiting the manhole.
Similarly, introducing a dissimilar metal such as steel between the rim and the cover is an invitation to galvanic corrosion, particularly in those areas which use rock salt or a similar material to treat snow and ice buildup on road surfaces.
Numerous solutions have been proposed in an effort to facilitate the adjustment of the rim elevation, as follows:
Pavement is removed adjacent to the structure, and shims are inserted under the casting to bring it to the proposed elevation of the wearing course. This method is commonly practiced on construction sites now, and further refinements are disclosed in patents such as U.S. Pat. No. 5,934,820 to Vernon W. Hinkle, U.S. Pat. No. 5,564,855 to Dennis C. Anderson, and U.S. Pat. No. 5,470,172 to Dwight G. Wiedrich.
Manipulation of the casting within the pavement, a method which purports to allow vertical adjustment of the rim elevation without disturbing the surrounding pavement, frequently fails in the field, possibly resulting in delays in paving the surrounding area. This technique is taught in U.S. Pat. No. 5,451,119 to John L. Hondulas, U.S. Pat. No. 5,318,376 to Everett J. Prescott, Sr., and U.S. Pat. No. 5,095,667 to Chester Ryan.
The casting is raised by manipulation of threaded bolts, as shown in U.S. Pat. No. 5,344,253 to Cesare Sacchetti, U.S. Pat. No. 4,925,337 to Hansruedi Spiess and Francoix Galvanetto, and U.S. Pat. No. 4,149,816 to Johannes L. Piso. These designs subject the casting to extreme point loading at each of the adjustment bolts, and create an opportunity for both mechanical failure and/or corrosion at each such bolt. Similarly, designs have been proposed which allow convenient adjustment of the elevation of the rim by the incorporation of steps in castings which mate in making up the rim as a whole. U.S. Pat. No. 5,360,131 to Guy M Phillipps and Wayne A Harris, U.S. Pat. No. 5,211,504 to Roger Trudel, and U.S. Pat. No. 4,906,128 to Roger Trudel all propose variations of steps in adjoining castings; and all impose point loading at the step locations in a manner similar to the point loading caused by the adjustment bolts as indicated above.
The cover elevation is raised by the insertion of a cylindrical shim under the cover. Here, a cylindrical section is added outside the perimeter of the cover to raise the elevation of the rim. Prior-art teachings frequently show the shim for the rim to be made of an insubstantial material, either disassociated from the cover shim entirely or connected with a thin strip of metal to facilitate the re-use of the original cover. U.S. Pat. No. 5,899,024 to Edward C. Stannard, U.S. Pat. No. 5,769,564 to David John Drake Hawkins, and U.S. Pat. No. 5,308,189 to Jean-Louis Claing all teach the use of such designs. The rim shim is prone to damage or destruction by vehicular traffic, snow plows, etc., due to its light section and marginal connection to the underlying cover shim. In many instances, the construction of the shim assembly results in the mating of dissimilar metals, and subsequently suffers the accelerated corrosion attendant upon such mating.
Numerous other methods have been advocated to facilitate the adjustment of structure elevations within pavement areas; none have achieved widespread acceptance for a variety of reasons, some of which are mentioned above. The ideal solution would permit the structure to remain flush with the surrounding pavement for an indeterminate period, and would permit the rapid adjustment of the elevation of both the rim and the cover immediately prior to milling or paving, without causing excessive delays to traffic and unnecessary expenses to the developer or municipality. Perhaps most importantly, the danger to motorists dodging traffic barricades and to workers protected by the barricades will be minimized, as casting elevations can be adjusted in minutes rather than days.
SUMMARY OF THE INVENTION
The invention provides an assembly for adjusting the elevation of a structure such as a manhole or a catch basin having a base rim surrounded by pavement, the base rim comprising an outer wall and a support shoulder extending inwardly from the wall and spaced downwardly from an upper end thereof. The assembly comprises a cover, and an adapter formed in a single piece to support the cover thereon and having upper and lower members. The lower member is receivable within the wall of the base rim to be supported on the shoulder thereof, the upper member extending outwardly of the lower member to receive the cover therewithin and upwardly to engage the upper end of the base rim and form an upward extension thereof. The lower member is formed with a plurality of inwardly extending protrusions distributed to form spaces therebetween and interconnecting the upper and lower members to form steps at the protrusions. The cover is receivable within the upper member to be supported on the lower member, the cover being formed with a plurality of indentations in a lower surface thereof, the indentations being dimensioned and disposed to receive the adapter protrusions therewithin. Portions of the cover above the indentations are dimensioned and disposed to be supported on the steps. With this construction, the elevation of the structure may be increased by supporting the assembly on the base rim of the structure and decreased by removing the adapter from between the base rim shoulder and the cover.
The vertical dimensions of the adapter may be calculated to raise the elevation of the structure through a distance smaller than the thickness of the cover when the adapter is inserted between the base rim and the cover.
The assembly may include one or more additional adapters of identical construction with the first, all the adapters being formed to nest within one another, the elevation of the structure thus being dependent upon the number of adapters inserted between the base rim and the cover.
Where the structure is a manhole, the base rim, the adapter and the cover are of generally cylindrical form.
On the other hand, where the structure is a catch basin, the base rim, the adapter and the cover are of generally rectangular form.
As described above, the assembly may be applied to an existing structure in which the base rim is of conventional configuration. However, for new installations, a base rim may be provided in accordance with the invention in which the base rim shoulder is formed with a plurality of upwardly extending protrusions dimensioned and disposed to be received in the spaces formed by the adapter protrusions in alternating relation with them.
Use of the invention allows pavement to be installed in new road sections without the necessity of leaving structures protruding from the initial lift or lifts pending installation of the final wearing course, which may not occur for a year or more
The invention facilitates adjustment of the rim elevation of structures in paved areas which are to receive an overlay, without requiring the removal of pavement around the structure
The invention also facilitates removal of the top layer of pavement adjacent to structures in paved areas by milling rather than requiring handwork.
The invention provides complete drainage around storm structures in the above circumstances, including those structures which may be located partially in a concrete curb and gutter and partially in a bituminous paving section
The invention allows rim elevation adjustment to be accomplished quickly and accurately minutes before the wearing course or overlay is placed
In short, the unique geometry of rims, covers, and adapters according to the invention permits the rapid adjustment of the elevation of manholes, catch basins, and other structures within paved areas. Such elevation adjustment can be accomplished without having to remove pavement or curb and gutter. Further, the unique geometry allows the adjustment to be carried out in minutes, just before the placement of new paving adjacent to the structure.
This ability reduces the danger to highway construction crews and motorists, reduces necessary funding for paving projects, and reduces traffic congestion caused by road repairs.
These and other features and advantages of the invention will be apparent from the ensuing description in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a plan view of a typical prior-art manhole cover assembly;
FIG. 1A is a cross-sectional view of the prior-art assembly of FIG. 1, showing a cover supported by an internal shoulder of a rim;
FIG. 2 is a view similar to FIG. 2, showing the placement of a prior-art height adapter in cross section;
FIG. 3 is a plan view of an embodiment of a manhole cover assembly according to the invention;
FIG. 3A is a sectional view taken along any one of lines A—A of FIG. 3;
FIG. 3B is a sectional view taken along any one of lines B—B of FIG. 3;
FIG. 4 is a view similar to FIG. 3;
FIG. 4A is a sectional view taken along any one of lines A—A of FIG. 4 and shows an adapter according to the invention installed beneath the cover;
FIG. 4B is a sectional view taken along any one of lines B—B of FIG. 4;
FIG. 4C is a perspective view of the assembly of FIG. 4;
FIG. 4D is an exploded view of the assembly of FIG. 4;
FIG. 5 is a view similar to FIG. 4A but shows an additional adapter according to the invention installed;
FIG. 5A is a perspective view of the assembly of FIGS. 5 and 6;
FIG. 5B is an exploded view of the assembly of FIGS. 5 and 6;
FIG. 6 is a view similar to FIG. 4B but shows the additional adapter of FIG. 5;
FIG. 7 is a sectional view similar to FIG. 4A but shows a second embodiment of an adapter according to the invention within a prior-art manhole rim;
FIG. 8 is a sectional view similar to FIG. 4B but shows the adapter of FIG. 7;
FIG. 9 is a plan view of an assembly including a manhole cover and a rim having a perimeter of constant radial section, the upper portion of the perimeter having reduced thickness;
FIG. 9A is a sectional view taken along line A—A of FIG. 9;
FIG. 10 is a view similar to FIG. 9A, but shows a third embodiment of an adapter according to the invention;
FIG. 11 is a view similar to FIG. 10, but shows an additional adapter conforming to the third embodiment thereof;
FIG. 12 is a sectional view, similar to FIG. 9A, of an assembly including a manhole cover having a perimeter of constant radial section, but shows a fourth embodiment of an adapter according to the invention within a prior-art manhole rim;
FIG. 13 is a plan view of an assembly including a manhole cover equipped with bolts to seal the cover to a rim;
FIG. 13A is a sectional view taken along line A—A of FIG. 13;
FIG. 13B is a sectional view taken along line B—B of FIG. 13;
FIG. 14A is similar to FIG. 13A, but shows a fifth embodiment of an adapter according to the invention;
FIG. 14B is similar to FIG. 13B, but shows a fifth embodiment of an adapter according to the invention;
FIG. 15 is a plan view of an embodiment of a catch-basin rim and cover assembly according to the invention;
FIG. 15A is a sectional view taken along line A—A of FIG. 15, and also shows a partial curb and gutter section;
FIG. 15B is a sectional view taken along line B—B of FIG. 15, and also shows the curb and gutter section;
FIG. 15C is a sectional view taken along line C—C of FIG. 15, and also shows a partial section of asphalt pavement;
FIG. 16 is a plan view identical with FIG. 15, but rotated to show a section line at right angles to lines A—A, B—B, and C—C of FIG. 15;
FIG. 16A is a sectional view taken along line A—A of FIG. 16;
FIG. 17 is a view similar to FIG. 16A, but shows a sixth embodiment of an adapter according to the invention;
FIG. 18 is a view similar to FIG. 16A, but shows a seventh embodiment of an adapter according to the invention;
FIG. 19 is a vertical sectional view of a typical prior-art catch basin assembly;
FIG. 20 is a view similar to FIG. 19, but shows an eighth embodiment of an adapter and a cover, both according to the invention, assembled with the catch- basin rim of the prior art;
FIG. 21 is a plan view of a second catch basin rim and cover assembly according to the invention;
FIG. 21A is a sectional view taken along line A—A of FIG. 21, and also shows a partial curb and gutter section;
FIG. 21B is a sectional view taken along line B—B of FIG. 21, and also shows the partial curb and gutter section;
FIG. 21C is a sectional view taken along line C—C of FIG. 21, and also shows a section of asphalt pavement;
FIG. 22 is a plan view identical with FIG. 21, but rotated to show a section line at right angles to lines A—A, B—B, and C—C of FIG. 21;
FIG. 22A is a sectional view taken along line A—A of FIG. 22;
FIG. 23 is a view similar to FIG. 22A, but shows a ninth embodiment of an adapter according to the invention;
FIG. 24 is a plan view of a third and preferred embodiment of a catch-basin cover according to the invention;
FIG. 24A is an elevational view taken along line A—A of FIG. 24;
FIG. 24B is an elevational view taken along line B—B of FIG. 24;
FIG. 25 is a plan view of a tenth and preferred embodiment of an adapter according to the invention;
FIG. 25A is an elevational view taken along line A—A of FIG. 25; FIG. 25B is an elevational view taken along line B—B of FIG. 25;
FIG. 26 is a perspective view of a catch-basin assembly according to the invention installed in a curb and gutter;
FIG. 27 is an exploded view of the assembly of FIG. 26;
FIG. 28 is a perspective view of a catch-basin assembly including a prior-art catch-basin rim and installed in a curb and gutter; and
FIG. 29 is an exploded view of the assembly of FIG. 28 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The prior art shown in FIG. 1 sought to provide a means of adjusting the elevation of a manhole or catch basin (or other structure) in a paved area by using a cover 30 , a rim 40 , and an overlay adapter 60 (FIG. 2 ). The cover shown is depicted as a circular disk, and is typically fabricated of cast iron. The rim is also typically cast iron and comprises a cylindrical wall provided with an internal shoulder 42 (FIG. 1A) which supports the cover at the elevation of the pavement adjacent to the rim. The rim shown in FIG. 1 is cylindrical, and fits snugly around the perimeter of the cover. The bottom of the rim is typically flared, and rests on a masonry structure (not shown) which is itself part of a larger underground infrastructure. A rim extension 44 extends upward beyond the internal shoulder, adjacent to and flush with the upper surface of the cover.
FIG. 1A shows the prior-art cover 30 and rim extension 44 above a leveling course 50 of asphalt and level with a wearing course 70 of asphalt. The overlay adapter 60 (FIG. 2) is used to support the cover at a higher elevation, and to provide an adapter extension 64 (FIG. 2) above the rim extension. The overlay adapter effectively increases the elevation of both the cover and the rim extension to allow the placement of an overlay 70 A (FIG. 2) of asphalt. The overlay adapter is also typically made of cast iron, and consists of a cylindrical support 62 interposed between the internal shoulder integral to the rim and the bottom of the cover in its elevated position, as well as the adapter extension. It will be noted that the necessity of an integral structural connection between the adapter extension and the cylindrical support dictates that the thickness of the overlay be somewhat greater than the thickness of the cover.
The prior art depicted in FIGS. 1, 1 A, and 2 requires that old pavement be cut from around the rim if the thickness of the overlay is less than or equal to the thickness of the cover, and that the rim be raised by inserting masonry and mortar between the rim and its masonry support. Any voids created by removal of old pavement and shimming the rim are typically filled with concrete, asphalt, or compacted granular material prior to the installation of the asphalt overlay, as an alternative to incurring the substantial expense of laying unusually thick asphalt overlays. The work preparatory to the placement of the asphalt overlay (cutting, shimming, and filling) often takes longer than the placement of the asphalt overlay, and creates additional expense, traffic congestion, and potential for liability.
In addition to the prior art shown in FIGS. 1, 1 A and 2 , a prior-art catch basin casting is depicted in FIG. 19 . It should be noted that the vertical section of the prior-art cover shown in FIG. 19 is not rectangular, as would be the case if the cover were truly cylindrical. Rather, it is trapezoidal, and represents a tapered edge where the cover meets the rim. Such a taper may be present in any of the casting designs (manhole, catch basin, etc.) shown and described herein, without affecting application of the invention. The invention may be similarly applied to catch basins (both those from the prior art and those according to the invention), and to manholes (again, both those from the prior art and those according to the invention), and to various other cast structures within paved areas (handholes, etc.). The invention's application to catch basins will be examined after considering its application to manholes.
An embodiment of a casting (such as a manhole) according to the invention, to be placed in a paved area, is shown in FIG. 3, as the casting would be initially installed. Similar to the prior art shown in FIG. 1, a rim extension 44 A and a cover 30 A are initially flush with the surrounding pavement. However, the cover 30 A and a rim 40 A have crenellated mating surfaces, as shown in FIGS. 3A, 3 B, 4 D and 5 B. The cover varies in thickness around its perimeter, providing full structural strength at section A—A, as shown in greater detail in FIG. 3 A. This section is identical in appearance with the prior-art section shown in FIG. 1A, having an internal shoulder 42 A 1 which supports the cover and any design load on it. The thickness of the perimeter of the cover is reduced at section B—B, as shown in greater detail in FIG. 3 B. This reduced section mates with a raised step 42 A 2 in the internal shoulder.
The embodiment of the invention shown in FIG. 4 demonstrates the manner in which the structure in FIG. 3 can be raised in minutes, rather than requiring hours (or days) using the technique described for the prior art. A laborer merely removes the cover 30 A, lays an overlay adapter 60 A on rim 40 A, and replaces the cover on the overlay adapter immediately prior to placement of the asphalt overlay. The overlay adapter consists of two sections, as shown in FIGS. 4A and 4B, which mate with the assembly sections shown in FIGS. 3A and 3B in the following manner.
The overlay adapter consists of two cylindrical members, the lower of which supports the cover at a new, higher elevation. This bottom cylindrical member is supported by internal shoulder 42 A 1 while supporting the cover on its upper surface, at support 62 A 1 (FIG. 4 A). Similarly, FIG. 4B shows the bottom cylindrical member supported by raised step 42 A 2 while supporting the cover on its upper surface, a support 62 A 2 . The second cylindrical member, an adapter extension 64 A, rests on the rim extension 44 A, and raises the elevation of the rim to match that of the cover. In FIG. 4A, these cylindrical members are separated. Note, however, that the cylindrical members making up the overlay adapter are structurally connected, as shown in FIG. 4B, which allows the fabrication of the overlay adapter as a single piece which can be cast entirely of the same material as the cover and rim. The overlay adapter can be secured to the rim using bolts or setscrews (not shown), or it can have a flange on its outermost diameter (not shown) to ensure that it is secured in place by the overlay. (Such methods of securing an adapter are known to one having ordinary skill in the design and fabrication of overlay adapters.)
In accordance with the invention, the geometries of the rim, the cover, and the overlay adapter allow the placement of an overlay of asphalt of thickness less than the thickness of the cover, while allowing the use of a one-piece, all-cast overlay adapter. The thick sections of the cover (FIG. 4A) ensure that design loads are transmitted to the rim, while the thin sections of the cover (FIG. 4B) permit an adequate structural connection between the two cylindrical sections of the overlay adapter. It should be noted that the overlay adapters can be stacked to accommodate successive adjustments to the elevation of the rim and cover without reducing the clear opening of the rim, as shown in FIGS. 5 and 6, which correspond to FIGS. 4A and 4B, respectively.
An overlay adapter 60 B, depicted in FIGS. 7 and 8, is intended for installation in existing, conventional structures and affords many of the same advantages as those described above in connection with FIGS. 4A to 5 B. The overlay adapter 60 B is similar in structure to overlay adapter 60 A in having a support 62 B 1 (FIG. 7) and a support 62 B 2 (FIG. 8) which correspond to supports 62 A 1 (FIG. 4A) and 62 A 2 (FIG. 4 B), respectively, of overlay adapter 60 A (FIGS. 4 to 4 B). Overlay adapter 60 B accommodates the conventional rim 40 by providing a thicker section under cover 30 A at support 62 B 2 . Overlay adapter 60 B and cover 30 A mate in the same manner as previously described in connection with FIGS. 4A and 4B.
Alternative means for raising the elevation of a manhole structure in pavement by a minimal amount are illustrated in FIGS. 9, 9 A and 10 . A rim 40 B is provided with a rim extension 44 B which is flush with the surface of the adjacent wearing course, and the rim supports a cover 30 B flush with the rim extension. The rim and cover differ from those disclosed in FIGS. 3 to 6 , however, in that the cover is supported on an internal shoulder 42 B 1 and a raised step 42 B 2 which extend around the entire perimeter of the cover, as shown in FIG. 9 A. FIG. 10 shows how the step provided between internal shoulder 42 B 1 and support 42 B 2 allows an overlay extension 64 C to be structurally connected to a support 62 C 2 , which is in turn structurally connected to a support 62 C 1 . These structural connections ensure that an overlay adapter 60 C can be used to raise the cover to the elevation of the overlay. The cylindrical members 64 C, 62 C 2 , and 62 C 1 making up the overlay adapter 60 C allow the fabrication of the overlay adapter as a single piece which can be cast entirely of the same material as the cover and rim. FIG. 11 illustrates how a plurality of overlay adapters 60 C can be stacked without reducing the clear opening of the structure.
Returning for the moment to FIGS. 7 and 8, it will be clear how an existing, conventional rim 40 can be augmented minimally to accommodate the placement of an asphalt overlay by discarding the original cover 30 and installing a cover 30 A on an overlay adapter 60 B, both being constructed in accordance with the invention. FIG. 12 discloses similar means for raising the existing rim 40 minimally, by discarding the original cover and installing a new cover 30 B, together with an overlay adapter 60 D. Overlay adapter 60 D is similar to overlay adapter 60 C, with the exception that a support 62 D 2 is thicker, to fit snugly against interior shoulder 42 of the prior-art rim 40 . A support 62 D 1 provides support under the bottom of the cover, as shown in FIG. 12 . The cover 30 B is supported at the same elevation as the adjacent overlay, and an overlay extension 64 D effectively raises the rim elevation (between the cover and the overlay) to that of the overlay. The cylindrical members 64 D, 62 D 2 , and 62 D 1 making up the overlay adapter 60 D allow the fabrication of the overlay adapter as a single piece which can be cast entirely of the same material as the cover and rim.
FIGS. 13 to 14 B address the application of the invention to a manhole which is to be sealed against infiltration. A cover 30 C is secured to rim 40 A by one or more bolts 32 , as shown in FIG. 13 . FIG. 13A shows a location for an O-ring 34 around the perimeter of the cover. FIG. 13B shows the same O-ring, and indicates how the O-ring passes through that section of the rim having reduced thickness. FIG. 14A corresponds to FIG. 13A but shows an overlay adapter 60 E in place. FIG. 14B corresponds to FIG. 14 B and shows the same overlay adapter. The overlay adapter 60 E is quite similar to that shown in FIGS. 4A and 4B, having an overlay extension 64 E, a support 62 E 2 , and a support 62 E 1 , which together allow the fabrication of the overlay adapter as a single piece which can be cast entirely of the same material as the cover and rim. The overlay adapter has provision for an additional O-ring 66 , however, which ensures that the overlay adapter 60 E will be sealed to the rim 40 A. The O-ring 34 in cover 30 C ensures the cover is sealed to the adapter; together, cover 30 C, overlay adapter 60 E, and bolt(s) 32 seal the structure to prevent infiltration.
The invention can be used to allow the adjustment of a variety of shapes of structures within paved areas. The rectangular catch basin shown in FIG. 15 shows how the invention can be applied to a rim 40 C which allows a rim extension 44 C of the rim 40 C to be installed flush with a concrete gutter 80 (FIGS. 15 A and 15 B), while allowing a cover 30 D to be structurally supported at a level suitable to drain the leveling course of asphalt in new roads, parking lots, etc.
The rectangular cover 30 D is typically made of cast iron, and is fabricated with a number of openings to admit liquid into the catch basin. The concrete gutter acts as a drainage channel in conveying liquid to the cover 30 D. The rim 40 C is also typically made of cast iron, and has an internal shoulder 42 C 1 (FIG. 15B) which provides structural support of the cover 30 D. The internal shoulder 42 C 1 has a raised step 42 C 2 (FIGS. 15A and 15C) which mate with reduced sections of the cover 30 D, in the same manner as previously described for crenellated rim 40 A and cover 30 A. The rim 40 C also has a rim extension 44 C along its uppermost edge, which rim extension is flush with the concrete gutter, as shown FIGS. 15A and 15B, and is flush with the leveling course of asphalt, as shown in FIG. 15 C.
FIG. 16A represents a section through rim 40 C and cover 30 D taken at right angles to the three sections represented in FIGS. 15A, 15 B and 15 C. FIG. 16A shows the rim extension 44 C flush with the concrete gutter where the rim is installed in the concrete. The section further shows a step down in the rim extension 44 C where the rim extends into the asphalt leveling course. The step in the rim extension 44 C, together with the support of the cover 30 D by the internal shoulder 42 C 1 at an elevation flush with that of the leveling course of asphalt, permits the asphalt to be drained readily into the cover 30 D.
Many municipalities prefer not to install the upper layer of asphalt while heavy construction traffic is using the pavement. When construction is nearing completion, the wearing course of asphalt is placed. Referring to FIG. 17, a wearing course adapter 60 F is shown placed between the rim 40 C and the cover 30 D. The wearing course adapter 60 F is supported on internal shoulder 42 C 1 and raised step 42 C 2 , and provides support for the cover 30 D on a support 62 F 1 and a support 62 F 2 , raising the cover to the elevation of the wearing course. The application of the inventive matter in raising covers of manholes, catch basins, etc. does not require that the support of the cover be contiguous around the perimeter of the cover. The wearing course adapter 60 F shown provides support of three sides of the cover 30 D; no support is provided along the rear side of the cover. A wearing course adapter extension 64 F raises the elevation of the rim extension 44 C to that of the wearing course. It will be noted that the presence of raised step 62 F 2 adjacent to the wearing course extension 64 F allows an integral structural connection between the components of the wearing course adapter 60 F, and further allows the wearing course adapter to be cast of a homogeneous material. It will be further noted that the placement of rim 40 C, wearing course adapter 60 F, and cover 30 D may be advantageous even in areas which receive the wearing course of asphalt immediately, as removal of the wearing course adapter 60 F will facilitate the milling of the wearing course, should the municipality or developer decide to remove and replace the wearing course. Similarly, installation of a wearing course adapter on manholes and other structures within the pavement will eliminate time and expense when the pavement is renovated by milling and replacing the wearing course.
Over time, the pavement surface is typically repaired a number of times. It may become necessary to place an asphalt overlay over existing paving (concrete, asphalt, etc.) which is nearing the end of its serviceability. FIG. 18 shows the installation of an overlay adapter 60 G which allows the cover 30 D to be raised to an elevation flush with the proposed elevation of the overlay. The overlay adapter provides support for the cover on a support 62 G 1 and a support 62 G 2 , raising the cover to the elevation of the overlay. The overlay adapter itself is supported by support 62 F 1 and 62 F 2 of the wearing course adapter 60 F. The overlay adapter also provides an overlay extension 64 G, which raises the elevation of the wearing course extension 64 F to that of the proposed elevation of the overlay. It will be apparent that the presence of raised step 62 G 2 adjacent to the overlay extension 64 G will allow an integral structural connection between the components of the overlay adapter 60 G, and further allows the overlay adapter to be cast of a homogeneous material. The similarity of the respective mating surfaces (of the rim, the wearing course adapter, the overlay adapter, and the cover) for new manholes (FIGS. 3 to 6 ) and for new catch basins (FIGS. 15 to 18 ) will be apparent when each of the respective components are compared.
FIG. 19 shows a prior-art catch basin rim and cover, typical of many presently installed in paved areas throughout the country. An internal shoulder 42 D integral to a rim 40 D supports a cover 30 E flush with the surface of the wearing course. A rim extension 44 D similarly extends the elevation of the rim itself, and ensures it is flush with the wearing course. The arduous conventional process of cutting the old pavement from around the structure, raising the casting by inserting masonry and mortar under the casting, and pouring a concrete collar around the structure prior to the installation of the new pavement can be averted using the teachings above, although the old cover must be discarded to take advantage of the adapter according to the invention.
FIG. 20 shows the same conventional rim 40 D, and illustrates placement of an overlay adapter 60 H, which has been modified to accommodate the conventional rim. This modification consists of thickening a support 62 H 2 of the overlay adapter to provide structural support of cover 30 E. The overlay adapter also provides a support 62 H 1 , which supports the cover, and an overlay extension 64 H, which raises the elevation of the rim extension 44 D to that of the proposed elevation of the overlay. It will be noted that the presence of raised step 62 H 2 adjacent to the overlay extension allows an integral structural connection between the components of the overlay adapter, and further allows the overlay adapter to be cast of a homogeneous material. As indicated above, the old cover is not compatible with the support surface of the adapter and must be discarded. Neither the new cover nor the overlay adapter will diminish the clear opening of the structure, however, and will be reusable should additional adapters be placed to accommodate additional asphalt overlays.
The method of draining the leveling course of asphalt which was discussed in relation to FIGS. 15 to 18 is also feasible if the municipality or developer mandates the use of steel segments in the wearing course adapters. FIG. 21 shows a rim 40 E, a cover 30 F, and a rim extension 44 E which are similar to those disclosed in FIGS. 15A to 15 C. The latter Figures show that cover 30 D is supported on internal shoulder 42 C 1 and on raised step 42 C 2 , while FIGS. 21A to 21 C show cover 30 F to be supported on an internal shoulder 42 E, there being no raised step present. Comparison of the two sets of figures will also reveal that the mating surfaces of the cover and the rim in FIGS. 21A to 21 C are slightly tapered. FIG. 23 shows how this slight taper allows the use of one or more steel connectors 68 J in wearing course adapter 60 J, between a wearing course extension 64 J and a support 62 J. The presence of a step in rim extension 44 E permits the use of a variant of the prior-art overlay adapters as disclosed in FIG. 23, permitting their use as wearing course adapters.
An embodiment of the invention perhaps preferred above the others previously described is shown in FIGS. 24 to 25 B. The previously described embodiments have more than one bearing surface (for example, internal shoulder 42 A 1 and raised step 42 A 2 shown in FIGS. 3 A and 3 B), and the cover may be prone to rocking as the casting wears. This rocking is due to differing degrees of support offered by the various bearing surfaces.
A cover 30 G shown in FIG. 24 is intended to prevent any such rocking. The cover is modeled after cover 7045 M 1 available from East Jordan Iron Works, Inc., but the front and rear corners of the cover have been removed. FIG. 24A shows a load bearing surface 130 along the side of the cover and a load bearing surface 120 at the front of the cover. FIG. 24B is a view of the front edge of the cover, and shows load bearing surface 130 at the left side, load bearing surface 120 at the front, and a load bearing surface 110 at the right side of the cover.
An overlay adapter 60 K, shown in FIG. 25, is designed to support the cover in the following manner. Load bearing surface 130 of the cover is supported by a load bearing surface 131 of the adapter, load bearing surface 120 of the cover is supported by a load bearing surface 121 of the adapter, and load bearing surface 110 of the cover is supported by a load bearing surface 111 of the adapter.
Loading imposed on the cover is therefore transmitted from the cover's load bearing surfaces to load bearing surfaces 111 , 121 , or 131 of the overlay adapter. The loading passes through the adapter to a load bearing surface 62 K 1 , which rests within rim 40 C (FIGS. 15 to 15 C). The upper surface of the overlay adapter which is adjacent to the overlay constitutes an overlay extension 64 K, and the thickened sections of the upper surface of the overlay adapter (which make up the front and rear comers of the cover which were removed) constitute an upper surface 62 K 2 .
Allowing the overlay adapter to extend completely to the surface of the cover in this manner eliminates the possibility that the cover will rock on adjacent supports (for example, on support 42 C 1 and support 42 C 2 in FIGS. 15B and 15A, respectively). It will be noted that while the embodiment of FIGS. 24 to 25 B has been illustrated as an overlay adapter for a catch basin, the same geometry is suitable for a wearing course adapter for a catch basin, or for either type of adapter for a manhole or other assembly within a paved area.
FIGS. 26 and 27 illustrate a catch basin assembly according to the invention which is similar in all essential respects to the catch basin assembly shown in FIGS. 24 to 25 B, whereas FIGS. 28 and 29 show a similar catch basin assembly installed in an existing, conventional catch basin rim. In FIGS. 26 to 29 , reference characters taken from FIGS. 24 to 25 B identify elements identical with or analogous to elements shown in those Figures.
In conclusion, it will be understood that the use of the structures according to the invention disclosed herein will permit the rapid adjustment of the elevation of various types of structures within paved areas. The speed with which the adjustments can be made will reduce the danger to highway workers and motorists, decrease the amount of time sections of roads will be closed or congested, and reduce the budgetary requirements necessary for either initial road paving or road restoration.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.
|
An assembly for adjusting the elevation of a structure such as a manhole or a catch basin to be surrounded by pavement. A one-piece is formed to be inserted between a base rim and a cover of the structure. A lower member of the adapter is received in the base rim to be supported on an internal shoulder. An upper member extends outwardly of the lower member to receive the cover and upwardly to engage the upper end of the base rim and form an upward extension of the rim. The elevation of the structure may be increased by inserting the adapter between the base rim shoulder and the cover and decreased by removing the adapter from between the base rim shoulder and the cover. Additional adapters of identical construction may be inserted to further increase the elevation of the structure, all the adapters being nestable within one another.
| 4
|
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] This invention was made with government support under contract number W56HZV-08-C-0525 awarded by the U.S. Army Tank Automotive Research, Development and Engineering Center. The United States government has certain rights in the invention.
BACKGROUND
[0002] The present invention relates to a wire neutralization system, and more specifically to a wire neutralization system for buried wires used to detonate explosive devices.
[0003] Military convoys occasionally travel through areas which may have explosive devices. These explosive devices may be triggered by a target presence sensor, a timer, or by a user controlled detonator. Examples of target presence sensors are trip wires, pressure plates, tilt sensors, and motion detectors, all of which infer the presence of a target from an input signal and automatically send a detonation signal, often through a control wire, to detonate the explosive device. Timers detonate an explosive device, usually by sending a detonation signal through a control wire, at a preselected time or within a preselected passage of time from a start time. User controlled detonators are operated by a human operator and may send the detonation signal via a control wire connected to the explosive device. The present invention is concerned with any type of explosive device that uses a buried wire of any kind to transmit a detonation signal or otherwise trigger the detonation of the explosive device. The buried wire may be buried in the terrain to mask the presence of the explosive device.
[0004] It would be useful to have a wire neutralization system that could neutralize buried wires. It would further be useful to be able to operate such a wire neutralization system while driving a vehicle designed to protect a driver from explosions. Such a vehicle could, for example, lead a military convoy to reduce the likelihood that the personnel and contents of the convoy will be harmed by an explosive device that uses a buried wire.
SUMMARY
[0005] In one aspect, the invention provides a wire neutralizing system for use with a vehicle, the wire neutralization system comprising: a frame adapted to be hitched to the vehicle; at least one wheel supporting the frame, a bottom of the wheel rolling over terrain having buried wires; and a blade movable between a stowed position in which the blade is above the bottom of the wheel and a deployed position in which the blade is below the bottom of the wheel; wherein the blade plows through the terrain to disable the buried wires when in the deployed position.
[0006] In some aspects of the invention, the wire neutralization system further comprises a wheel suspension unit permitting vertical travel of the wheel with respect to the frame in response to rough terrain. In some aspects of the invention, the wire neutralization system further comprises a suspension lockout feature that prevents relative vertical travel of the wheel with respect to the frame while the blade is deployed. In some aspects of the invention, the wire neutralization system further comprises a hydraulic system for moving the blade between the stowed and deployed positions. In some aspects of the invention, the blade comprises a plurality of blades; the wire neutralization system further comprising a hydraulic system for simultaneously moving the plurality of blades between the stowed and deployed positions. In some aspects of the invention, the wire neutralization system further comprises a blade trip biasing member biasing the blade toward the deployed position and accommodating movement of the blade toward a tripped position upon the blade meeting a tripping resistance while in the deployed position. In some aspects of the invention, the wire neutralization system further comprises a blade lift biasing member biasing the blade toward the deployed position and accommodating movement of the blade toward a lifted position upon the blade meeting a lifting resistance while in the deployed position.
[0007] In some aspects of the invention, the wire neutralization system further comprises a blade plate moveable mounted to the frame; and a blade station attached to the blade plate, the blade station including: a blade arm mounted to the blade plate; and a blade holder mounted to the blade arm and supporting the blade. In some aspects of the invention, the blade is movable between the stowed position and the deployed position by moving the blade plate with respect to the frame. In some aspects of the invention, the blade plate is pivotably interconnected to the frame and the blade arm is pivotably interconnected to the blade plate such that the blade moves between the stowed and deployed positions in response to the blade plate being pivoted relative to the frame. In some aspects of the invention, the blade plate further includes a blade station mounting tab to mount the blade station to the blade plate.
[0008] In another aspect, the invention provides a wire neutralizing system for use with a vehicle, the wire neutralization system comprising: a frame adapted to be hitched to the vehicle; at least one wheel supporting the frame, a bottom of the wheel rolling over terrain having buried wires; a blade plate movably mounted to the frame; and a blade station attached to the blade plate including: an blade arm mounted to the blade plate; a blade holder mounted to the blade arm; and a blade supported by the blade holder; wherein the blade is movable between a stowed position in which the blade is above the bottom of the wheel and a deployed position in which the blade is below the bottom of the wheel by moving the blade plate with respect to the frame; wherein the blade plows through the terrain to disable the buried wires when in the deployed position.
[0009] In some aspects of the invention, the wire neutralization system further comprises a wheel suspension unit permitting vertical travel of the wheel with respect to the frame in response to rough terrain; and a suspension lockout feature that prevents relative vertical travel of the wheel with respect to the frame while the blade is deployed. In some aspects of the invention, the suspension lockout feature includes a lockout engagement groove, the lockout engagement groove engageable by the blade plate such that a force pathway is created between the wheel and the frame through the blade plate. In some aspects of the invention, the blade plate is movable relative to the frame via a hydraulic system. In some aspects of the invention, the blade plate is pivotably interconnected to the frame and the blade arm is pivotably interconnected to the blade plate such that the blade moves between the stowed and deployed positions in response to the blade plate being pivoted relative to the frame.
[0010] In some aspects of the invention, the blade plate includes a blade station mounting tab to mount the blade station to the blade plate. In some aspects of the invention, the wire neutralization system further comprises a blade lift biasing member connected to the blade station mounting tab and the blade arm to bias the blade toward the deployed position and accommodating movement of the blade toward a lifted position upon the blade meeting a lifting resistance while in the deployed position. In some aspects of the invention, the blade arm includes a stop member that engages a portion of the blade station mounting tab to prevent further movement of the blade while in the lifted position.
[0011] In some aspects of the invention, the wire neutralization system further comprises a blade trip biasing member connected to the blade holder and the blade arm to bias the blade toward the deployed position and accommodating movement of the blade toward a tripped position upon the blade meeting a tripping resistance while in the deployed position.
[0012] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a wire neutralization system of the present invention attached to a military vehicle.
[0014] FIG. 2 is a rear perspective view of a bank assembly from the wire neutralization system of FIG. 1 .
[0015] FIG. 3 is a front perspective view of the bank assembly of FIG. 2 .
[0016] FIG. 4 is a rear view of the bank assembly of FIG. 2 without a cover plate.
[0017] FIG. 5 is a perspective view of a portion of the bank assembly of FIG. 2 illustrating the trailing arms.
[0018] FIG. 6 is a perspective view of a blade station from the bank assembly of FIG. 2
[0019] FIG. 7 is a side view of the bank assembly of FIG. 2 with the blade in a stowed position.
[0020] FIG. 8 is a side view of the bank assembly of FIG. 2 with the blade in a deployed position.
[0021] FIG. 9 is a side view of the bank assembly of FIG. 2 with the blade in a lifted position.
[0022] FIG. 10 is a perspective view of a portion of the bank assembly of FIG. 2 illustrating an engagement bar in a lockout groove.
DETAILED DESCRIPTION
[0023] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
[0024] FIG. 1 illustrates a wire neutralization system 100 configured to be attached to a vehicle 104 . Generally, the wire neutralization system 100 is configured to roll over rough terrain that may contain buried wires 108 ( FIG. 7 ) attaching one or more explosive devices to a respective detonator. The term “wire” refers to any wire of any kind that can transmit a detonation signal or otherwise trigger the detonation of the explosive device. The system 100 is attached to the front of the vehicle 104 , such that as the vehicle 104 is driven over the terrain, the system 100 is pushed along the terrain in front of the vehicle 104 . Alternative, the system 100 may be pulled along the terrain by the vehicle 104 (e.g., towed behind the vehicle 104 ). The wire neutralization system 100 includes one or more blades 112 that may be deployed into the ground to plow through the terrain and neutralize the buried wires 108 . The term “neutralize” and its variants will be used herein to mean uprooting, cutting, or otherwise deactivating or rendering inoperable a wire for its intended purpose, and to mean exposing a wire or a portion of a wire to make the wire more easily detectable. In the illustrated embodiment, the vehicle 104 is a military vehicle 104 designed to protect a user or driver from harm in the event that a close proximity explosion is triggered while neutralizing the wires 108 coupled to any explosive devices. Alternatively, other vehicles 104 that are sufficient for a desired application may be used in conjunction with the wire neutralization system 100 .
[0025] The wire neutralization system 100 includes an attachment base 116 that hitches one or more bank assemblies 120 to the front of the vehicle 104 . Each of the bank assemblies 120 attaches to the base 116 via a caster pin 124 . The bank assemblies 120 are able to freely rotate about the caster pins 124 with respect to the base 116 , such that bank assemblies 120 are able to pivot in the desired direction when the vehicle 104 turns or the landscape slopes. Additionally, the attachment base 116 and the bank assemblies 120 each have a rolling degree of freedom that allows for rotation about a horizontal axis. The rolling degree of freedom allows the system 100 to balance or adjust to laterally undulating terrain.
[0026] FIGS. 2-4 illustrate one bank assembly 120 according to an embodiment of the present invention. The illustrated bank assembly 120 includes a bank frame 128 , a plurality of trailing arms 132 supporting one or more wheels 134 , a blade plate 136 , and one more blade stations 140 attached to the blade plate 136 . The bank assembly 120 also includes a plurality of bank roll shocks 122 , which may stabilize bank flutter at high speeds (e.g., speed greater than 20 mph). In the illustrated embodiment, the bank assembly 120 includes two trailing arms 132 and two wheels 134 , but in alternative constructions the bank assembly 120 may include more or fewer than two trailing arms 132 and wheels 134 . The blade plate 136 is moved relative to the bank frame 128 by hydraulically moving or operating a hydraulic actuator 142 (i.e., extending and retracting the actuator's piston relative to its cylinder) attached to both the blade plate 136 and the bank frame 128 . As a result, the blade stations 140 are also moved relative to the bank frame 128 when the hydraulic actuator 142 is moved. The bank assembly 120 also includes a cover 144 ( FIG. 1 ) attached to the bank frame 128 that prevents dirt and debris being kicked-up from the wheels 134 from obscuring the view of the vehicle operator. Additionally, the cover 144 ( FIG. 1 ) may also be formed of a material that helps protect the driver from harm in the event of a triggered explosion.
[0027] The bank frame 128 of the bank assembly 120 includes a substantially planar bank plate 148 supporting a plurality of blade plate pivot mounts 152 ( FIGS. 2 and 3 ) on a top surface and a plurality of trailing arm mounts 156 ( FIGS. 2 and 3 ) on a bottom surface. As mentioned earlier, the bank frame 128 is attached to the base 116 via the caster pin 124 , which hitches the bank frame 128 to the vehicle 104 . Specifically, the caster pin 124 is attached to the plate 148 via gussets 160 . The gussets 160 also support a plurality of suspension mounts 164 . Further, a cylinder mount 166 ( FIG. 5 ) extends from the bottom surface of the plate 148 for attachment to the hydraulic actuator 142 .
[0028] FIGS. 3 and 5 illustrate the trailing arms 132 of the bank assembly 120 . The trailing arms 132 have a first end supporting the attached wheels 134 for rotational movement and a second end that is pivotally attached to the bank frame 128 at the trailing arm mounts 156 . The trailing arms 132 , including the wheels 134 , are also connected to the bank frame 128 through multiple suspension units 168 to further support the bank frame 128 and for permitting vertical travel of the wheels 134 with respect to the bank frame 128 in response to rough terrain. As the bank assembly 120 encounters rough terrain, the trailing arms 132 are able to pivot relative to the bank frame 128 about the mounts 156 when a force exerted on the wheels 134 overcomes the biasing force of the suspension units 168 . The suspension units 168 include various energy absorbing features (e.g., a spring, viscous fluid, etc.) that enable the suspension units 168 to help dissipate the force exerted on the wheels 134 as a result of the rough terrain.
[0029] In reference to FIG. 2 , the blade plate 136 includes a plurality of attachment arms 172 extending toward the bank frame 128 . The attachment arms 172 pivotally connect the blade plate 136 to the blade plate pivot mounts 152 of the bank frame 128 . The blade plate 136 is then connected to the hydraulic actuator 142 by a pair of mounting tabs 176 so that the blade plate 136 is raised when the hydraulic actuator 142 is extended and the blade plate 136 is lowered when the hydraulic actuator 142 is refracted. The hydraulic actuator 142 is fluidly coupled to the remainder of a hydraulic system by hydraulic lines and actuated by a control panel mounted within the vehicle 104 for manipulation by a user. In reference to FIG. 10 , when the hydraulic actuator 142 is fully retracted, and the blade plate 136 is fully lowered or deployed, an engagement bar or portion 232 of the blade plate 136 engages a suspension lockout feature or groove 180 ( FIGS. 5 and 10 ) formed in the trailing arms 132 . The engagement of the blade plate 136 with the lockout groove 180 prevents substantially vertical travel of the wheels 134 relative to the bank frame 128 . When the blade plate 136 is engaged with the lockout groove 180 , a force pathway is created between the wheel 134 and bank frame 128 that is primarily directed through the blade plate 136 , and not the suspension units 168 . The alternative force pathway prevents the suspension units 168 from compressing, thereby assisting in the wire neutralizing capabilities of the system 100 , as will be described below. Although the lockout feature 180 is illustrated as a groove 180 , it is to be understood that the lockout feature 180 could be any other structure or feature that is capable of preventing the full use of the suspension units 168 . The blade plate 136 additionally includes a plurality of blade station mounting tabs 184 , which are used to attach the blade stations 140 .
[0030] FIG. 6 illustrates a single blade station 140 according to an embodiment of the present invention with portions removed to illustrate various enclosed features. The blade station 140 includes a blade arm 188 pivotally connected to the blade station mounting tab 184 and a blade holder 192 pivotally connected to the blade arm 188 . The blade holder 192 supports a blade 112 , which extends past the blade holder 192 to expose a cutting edge 204 for insertion into the terrain to neutralize the buried wires 108 . The blade station 140 also includes an overload trip biasing member 208 coupled to both the blade holder 192 and the blade arm 188 . Additionally, the blade station 140 includes an overload lift biasing member 212 coupled to both the blade arm 188 and the blade station mounting tab 184 . The purpose of the biasing members 208 , 212 will be described in detail below.
[0031] In continued reference to FIG. 6 , the blade 112 includes two sets of cutting edges 204 (i.e., first and second cutting edges 204 at opposite ends of the blade 112 ) such that the blade 112 can be oriented in two positions. The double-edged blade 112 allows the user to change the orientation of the blade 112 between first and second orientations. In the first orientation, the first cutting edge 204 is use while the second cutting edge 204 is in reserve within the blade holder 192 . The operator may switch to the second orientation of the blade 112 when the first cutting edge 204 becomes dull or damaged. In the second orientation, the second cutting edge is placed into use and the first cutting edge is in reserve. The cutting edge 204 that is in use extends beyond the blade holder 192 so it can engage and cut through the terrain. While in either the first or second orientation, the position of the blade 112 is fixed relative to the blade holder 192 . Specifically, the blade 112 is attached to the blade holder 192 by a mount or fastener 216 while two blocks 220 prevent rotation of the blade 112 about the fastener 216 . Further, the cutting edges 204 are made from a carbide material to help prevent excessive wear of the cutting edges 204 and extend the lifetime of the blade 112 . Alternatively, or in addition, other types of blades 112 not illustrated (e.g., singled-edged blades, etc.) may be used with the wire neutralization system 100 .
[0032] FIG. 7 illustrates the wire neutralization system 100 with the blade 112 in a retracted or stowed position. To move the blade 112 into the stowed position, the hydraulic actuator 142 is extended, causing the blade plate 136 and the blade station 140 to be lifted relative to the bank frame 128 so that the blade 112 is above the bottom of the wheel 134 . FIG. 8 illustrates the wire neutralization system 100 with the blade 112 in the deployed position. The blade 112 is moved from the stowed position ( FIG. 7 ) into the deployed position ( FIG. 8 ) by retracting the hydraulic actuator 142 , which lowers the blade plate 136 and the blade station 140 relative to the bank frame 128 . The illustrated wire neutralization system 100 fails into the deployed position because if hydraulic fluid is lost the hydraulic actuator 142 will retract under the weight of the assembly it supports. In other configurations, the wire neutralization system 100 can be made to fail into the stowed position as a matter of design preference.
[0033] When the blade station 140 is lowered, a portion of the blade 112 , including the cutting edge 204 , is inserted into the ground. In the illustrated embodiment, the blade 112 extends below the bottom of the wheel 134 by approximately two inches while in the deployed position. In other embodiment, the blade 112 may extend more or less than two inches below the bottom of the wheel 134 . While the blade 112 is extended into the ground and the vehicle 104 is moving, the blade 112 is subjected to drag loads.
[0034] As illustrated in FIG. 8 , the drag loads cause the blade 112 to pivot relative to the blade arm 188 into an operating position (shown with solid lines) from a non-operating position (shown with phantom lines). During typical operation, the blade 112 and blade holder 192 are pushed back to a position in a range from 90 degrees to 135 degrees in relation to the blade arm 188 , depending on the drag load exerted on the blade 112 by the terrain or ground. This may result in a forward sweeping motion of the blade 112 toward the non-operating position when the blade 112 transitions from hard terrain to soft terrain or a hole.
[0035] Additionally, the blade 112 may encounter hard objects (e.g., rocks) while it is extended into the ground that may exert a large impact force or resistance on the blade 112 . A large impact force may cause damage to the blades 112 . Therefore, the plurality of overload biasing members 208 , 212 are provided to allow controlled movement of the blade 112 relative to the bank frame 128 during such an impact force. The impact force may have a horizontal force component, or tripping resistance, that causes the blade 112 and blade holder 192 to rotate relative to the blade arm 188 into a tripped position (rotated further than the operating position) causing the overload trip biasing member 208 to compress and absorb some of the impact. After impact, the biasing force of the trip biasing member 208 forces the blade 112 back into the typical deployed or operating position.
[0036] Similarly, the impact force caused by a hard or dense objet may have an upward force component, or lifting resistance, on the blade 112 . The upward force causes the blade arm 188 to rotate relative to the blade station mounting tab 184 into a lifted position ( FIG. 9 ) causing the overload lift biasing member 212 to compress and absorb some of the impact. The blade arm 188 includes a stop member or cylindrical stop 224 that engages with an arcuate groove 228 formed in the blade station mounting tab 184 to prevent further vertical movement of the blade 112 past the lifted position. After the impact, the biasing force of the lift biasing member 212 forces the blade 112 back into the deployed or operating position. The impact force acting on the blade 112 may also cause both the biasing members 208 , 212 to be compressed, allowing the blade 112 to move vertically and horizontally in relation to the bank frame 128 .
[0037] In operation, the blades 112 of the bank assemblies 120 are positioned in the deployed position. While the blades 112 are in the deployed position, the blade plate 136 engages with the lockout groove 180 (i.e., the engagement bar 232 is received by the lockout groove 180 ) to provide constant engagement of the blades 112 with the ground or terrain, as illustrated in FIG. 10 . As such, the suspension units 168 are prohibited from compressing such that wheel 134 will not move vertically relative to the bank frame 128 and the blades 112 , keeping the blade 112 deployed at the intended depth, which may be approximately two inches. Once the blades 112 are deployed, the vehicle 104 may drive along a desired route to neutralize wires 108 attached to explosive devices that are buried in the ground. While driving, the blades 112 are able to move relative to the bank frame 128 in response to varied terrain density or in reaction to hard objects, as described above. Once the vehicle 104 has arrived at its destination, and the plowing of terrain is no longer necessary, the blades 112 are lifted into the stowed position, the engagement bar 232 is removed from the lockout groove 180 , and the suspension units 168 are operational. While the blades 112 are in the stowed position, the vehicle 104 may drive on any type of road (e.g., paved, gravel, etc.) without causing damage to the road as a result of the blades 112 . It is to be understood that the wire neutralization system 100 of the present invention is capable of being pushed, pulled, or moved at high speeds while attached to the vehicle 104 . In some embodiment, the wire neutralization system 100 may be driven at a speed in excess of 20 mph (miles per hour). In other embodiments, the system 100 may be driven at a speed in excess of 45 mph. In yet another embodiment, the system 100 may be driven at a speed in excess of 60 mph.
[0038] Various features and advantages of the invention are set forth in the following claims.
|
A wire neutralizing system for use with a vehicle including a frame adapted to be hitched to a vehicle. At least one wheel supports the frame while a bottom of the wheel rolls over terrain having buried wires. The system also includes a blade movable between a stowed position in which the blade is above the bottom of the wheel and a deployed position in which the blade is below the bottom of the wheel, such that the blade plows through the terrain to disable buried wires when in the deployed position.
| 5
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of provisional patent Ser. No. 61/491,290, filed 2011 May 30 by the present inventor.
BACKGROUND
[0002] This application relates to grip and finger strength, particularly to methods to build finger and grip strength
PRIOR ART
[0003] The following is a tabulation of some prior art that presently appears relevant:
[0000]
US Patents
Pat. No.
Kind Code
Issue Date
Patentee
D558,283 S
B1
2007-12-25
Mollet
D484,929 S
B1
2006-01-06
Mollet
6,022,299
B1
200-02-08
Stewart
[0004] Finger strength is an important part of many sports including but not limited to climbing, weightlifting and self defense. Many enthusiasts of these and other sports train on exercise machines in gyms or at home. They also use many forms of training that utilize resistance, whether it be the weight of their own body or the weight of metal plates on a cable pulley exercise machine or a rubber strap, band or tube. Many climbers utilize hangboards that are placed over a doorway in their home, exercise gym or artificial climbing facility. Many artificial climbing facility's provide climbers with training methods to promote and develop finger strength.
[0005] Although hangboards are useful for climbers to build finger strength they are limited. This is due to fact that they are designed to hang from. When hanging from a hangboard using finger strength, only slow twitch muscles are engaged. When someone is actively climbing, both fast twitch and slow twitch muscle groups are required to hold on and pull oneself upwards.
[0006] Cable pulley machines are useful in developing arm strength. While training on a cable machine the user can develop and strengthen fast twitch muscles. This however does not train finger strength, as the handle is usually a round steel bar that the whole hand can easily wrap around.
SUMMARY
[0007] In accordance with one embodiment, the finger strengthening device is comprised of but not limited to a molded shape that has various edges, ledges and cavities with a ring or u bolt connector embedded that can be attached to a resistance training device.
Advantages
[0008] The finger strengthening device can be attached to a variety of resistance training devices. In some cases this allows the user to set a chosen amount of weight while training finger strength or pinch strength. This minimizes the risk of injury associated with hangboards or resistance training that utilizes body weight. It also provides a methodical way to incrementally develop finger strength, by conditioning the small tendons and pulleys in the fingers.
DRAWINGS
FIGS. 1 A, 1 B, 1 C 1 D—First Embodiment
[0009] FIG. 1A shows a side view of this embodiment of the device.
[0010] FIG. 1B shows a back view of this embodiment of the device.
[0011] FIG. 1C shows a front view of this embodiment of the device.
[0012] FIG. 1D shows a perspective view of this embodiment of the device with the connector ring component shown outside the main body.
REFERENCE NUMERALS
FIGS. 1 A, 1 B, 1 C and 1 D—First Embodiment
[0013]
[0000]
101
Connector ring ⅜ × 5″ Eye Bolt
102
⅜ Nut mounted on 5″ Eye bolt
103
⅜ Washer mounted on 5″ Eye bolt
104
⅜ Nut mounted on 5″ Eye bolt
105
⅜ Nut mounted on 5″ Eye bolt
106
⅜ Washer mounted on 5″ Eye bolt
107
⅜ Nut mounted on 5″ Eye bolt
108
Vertical pinch grip
109
Large finger ledge
110
Small finger ledge
111
Cavity for medium width pinch
112
Wide pinch
113
Cavity for medium width pinch
114
Medium sloped finger ledge
115
Medium flat finger ledge
116
Thumb catch for sloper
117
Sloper area
DETAILED DESCRIPTION
FIGS. 1 A, 1 B, 1 C and 1 D—First Embodiment
[0014] The finger strengthening device is made up of two main components: the main body and the connector ring. The connector ring component is comprised of a ring with nuts and washers. The main body is shaped so that it is suitable to be gripped by a human hand for the purpose of training grip and finger strength.
[0015] One embodiment of the finger strengthening device is illustrated in FIGS. 1A , 1 B, 1 C and 1 D. This embodiment includes a 101 connector ring, 102 , 104 , 105 , 107 four ⅜ nuts, 103 , 106 two ⅜ washers, a 108 vertical pinch area, 109 , 110 , 114 , 115 four finger ledges of varied size, a 111 , 113 medium sized horizontal pinch area, a 112 wide horizontal pinch area and a 117 sloped area with a 116 thumb catch.
Operation
FIGS. 1 A, 1 B, 1 C, 1 D
[0016] The 101 connector ring can be attached to a resistance device and hung vertically. While in the vertical position the 108 vertical pinch area and the 109 , 110 , 114 , 115 four finger ledges and the 117 sloped area with 116 thumb catch can be utilized while the device is pulled downwards on any type of resistance.
[0017] The 101 connector ring can be attached to a horizontal resistance device. While on a horizontal resistance device the 111 , 113 medium sized pinch and the 112 wide sized pinch can be utilized while pulling in a horizontal direction.
Fabrication
[0018] The finger strengthening device can be made through the technique of casting and molding. The main body shape is carved and then a mold is made from the carving.
[0019] The connector ring is embedded in the mold. The martial to be used is then poured into the mold cavity as a liquid where it surrounds the nuts and washers on the connector ring or u-bolt prior to hardening. The connector component cannot be pulled out of the main body once the material hardens.
Additional Embodiments
2 A, 2 B, 2 C, 2 D—Additional Embodiments
[0020] FIG. 2A shows a side view of an additional embodiment.
[0021] FIG. 2B shows a front view of an additional embodiment.
[0022] FIG. 2C shows a perspective view of an additional embodiment with the connector u-bolt component shown outside the main body.
[0023] FIG. 2D shows a perspective view of an additional embodiment with the connector u-bolt component mounted.
Reference Numerals
FIGS. 2 A, 2 B, 2 C, 2 D—Additional Embodiments
[0024]
[0000]
201
Connector U-bolt
202
⅜ Nut mounted on U-bolt
203
⅜ Nut mounted on U-bolt
204
Plate mounted on U-bolt
205
⅜ Nut mounted on U-bolt
206
⅜ Nut mounted on U-bolt
207
Medium pinch grip
208
Wide pinch grip
209
Medium pinch grip
210
Wide pinch grip
211
Sloper grip area
Detailed Description
FIGS. 2 A, 2 B, 2 C and 2 D—Additional Embodiment
[0025] This embodiment of the finger strengthening device is made up of two main components: the main body and the connector u bolt. The connector u bolt component is comprised of a u bolt with nuts and a plate. The main body is shaped so that it is suitable to be gripped by a human hand. This embodiment is rectangular on one axis and has a curved surface leading up to the connector u-bolt as seen in FIG. 2A .
Operation
FIGS. 2 A, 2 B, 2 C and 2 D—Additional Embodiment
[0026] The 201 connector u-bolt can be attached to a resistance device and hung vertically or horizontally. While in the vertical position the 211 Sloper grip area can be held while the device is pulled downwards on any type of resistance. The 207 , 209 medium pinch grip areas and 208 , 210 wide pinch grip areas can be used with fingers and thumb inserted on each side to create a wide grip for the hand and pulled on vertically or horizontally
3 A, 3 B, 3 C and 3 D—Additional Embodiments
[0027] FIG. 3A shows a side view of an additional embodiment.
[0028] FIG. 3B shows a front view of an additional embodiment.
[0029] FIG. 3C shows a perspective view of an additional embodiment with the connector u-bolt component shown outside the main body.
[0030] FIG. 3D shows a perspective view of an additional embodiment with the connector u-bolt component mounted.
Reference Numerals
FIGS. 3 A, 3 B, 3 C, 3 D—Additional Embodiments
[0031]
[0000]
301
Connector U-bolt
302
⅜ Nut mounted on U-bolt
303
⅜ Nut mounted on U-bolt
304
Plate mounted on U-bolt
305
⅜ Nut mounted on U-bolt
306
⅜ Nut mounted on U-bolt
307
Thumb catch/palm stabilizer
308
Sloper grip area
Detailed Description
FIGS. 3 A, 3 B, 3 C and 3 D—Additional Embodiment
[0032] This embodiment of the finger strengthening device is made up of two main components: the main body and the connector u bolt. The connector u bolt component is comprised of a u bolt with nuts and a plate. This embodiment is spherical in shape and the u-bolt is centered in the sphere.
Operation
FIGS. 3 A, 3 B, 3 C and 3 D—Additional Embodiment
[0033] The 301 connector u-bolt can be attached to a resistance device and hung vertically or horizontally. While in the vertical position the 308 Sloper grip area can be held while the device is pulled downwards on any type of resistance while the 307 palm stabilizer is against the palm of the users hand. The sphere can also be held like a ball and pulled towards the users body.
Alternative Embodiments
[0034] There are many possibility's for alternative embodiments. Although the descriptions above contain many specificities, these should not be construed as limiting the scope of the embodiments but as merely providing illustrations of some of several embodiments. For example, the molded shape can be square, rectangular, spherical, triangular, ovular or any other shape that creates a grip able part that is beneficial for training grip strength. The connector point can be a ring, a loop, hook, a u shape or any shape that is suitable for connecting to a resistance device.
[0035] Thus the scope of the embodiments should be determined by the appended claims and their legal equivalents, rather than by the examples given.
|
Disclosed herein is a device for finger and grip strength exercise. The finger strengthening device comprises a molded shape with ledges and cavity's suitable for gripping by a human hand with a connector ring or u-bolt mounted therein whereby connector ring can be attached to resistance training device.
| 0
|
This application is a continuation of application Ser. No. 08/348,222 filed Nov. 28, 1994, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a developing device which is used in an image forming apparatus such as a copying machine, a printer, or the like, and which develops an electrostatic latent image on an image carrier.
2. Related Background Art
As conventional electrophotography methods, a large number of methods are known, as described in U.S. Pat. No. 2,297,691, Japanese Patent Publication Nos. 42-23910 and 43-24748, and the like. In general, an electrical latent image is formed on a photosensitive body consisting of a photoconductive material, by one of various means, a toner image is formed using a toner, the toner image is transferred onto a transfer medium such as a paper sheet, as needed, and the toner image transferred onto the transfer medium is fixed by heat, a vapor of a solvent, or the like, thus obtaining a copy. Also, various methods of visualizing an electrical latent image using a toner are known.
As developing methods, a large number of developing methods, for example, a magnetic brush developing method described in U.S. Pat. No. 2,874,063, a powder cloud method described in U.S. Pat. No. 2,221,776, a fur brush method, a liquid developing method, and the like, are known.
Of these developing methods, a magnetic brush method, a cascade method, a liquid developing method, and the like, which use a developing agent mainly consisting of a toner and a carrier, have widely been put into practice. These methods are excellent in that they can relatively stably obtain satisfactory images, but have common drawbacks associated with a two-component developing agent, i.e., degradation of the carrier and a variation in mixing ratio of the toner and carrier.
In order to avoid such drawbacks, various developing methods using a one-component developing agent consisting of only a toner have been proposed. For example, U.S. Pat. No. 3,909,258 proposes a method of developing an image using a magnetic toner having conductivity. In this method, a conductive magnetic toner is supported on a cylindrical conductive sleeve having a magnetism therein, and an electrostatic latent image is developed by bringing the sleeve into contact with the latent image. In this case, a conductive path is formed between the surface of a recording medium and the surface of the sleeve by toner particles on a developing region, an electric charge is guided from the sleeve to the toner particles via the conductive path, and the toner particles become attached to an image portion by a Coulomb force with the electrostatic latent image portion, thereby developing the image. The developing method using a conductive magnetic toner is an excellent method since it can avoid conventional problems associated with a two-component toner. However, since the toner is conductive, it is difficult to electrostatically transfer the developed image from the recording medium to a final support member such as a normal paper sheet.
In order to solve this problem, as a developing method using a high-resistance toner which can be electrostatically transferred, a developing method utilizing dielectric polarization of toner particles is described in Japanese Laid-Open Patent Application No. 52-94140. However, this method has drawbacks such as a low developing speed at which the developed image cannot have a sufficient density, and it is difficult to put this method into practical use. As another method using a high-resistance toner, a method of developing an image by triboelectrification, i.e., electrification of toner particles by friction between toner particles themselves or friction between toner particles and a sleeve, and bringing the charged toner particles into contact with an electrostatic holding member, is known. However, this method has the following drawbacks. That is, the number of times of contact between the toner particles and the friction member is small, and the toner particles are often insufficiently triboelectrified. In addition, when the Coulomb force between the charged toner particles and the sleeve is strong, the toner particles easily cohere. Thus, it is pointed out that many practical problems remain unsolved.
Japanese Laid-Open Patent Application No. 54-43036 proposes a novel developing method which can eliminate the above-mentioned drawbacks. In this method, a very thin toner layer is coated on a developing sleeve, is triboelectrified, and is brought very close to an electrostatic latent image under the influence of a magnetic field to face the image without contacting it, thereby developing the image.
According to this method, since a very thin layer of a magnetic toner is coated to increase the number of times of contact between the magnetic toner and the developing sleeve, a triboelectrification electric charge amount required for development can be developed in the toner.
However, even in the above-mentioned method, it is known that the number of times of contact between the developing sleeve and the magnetic toner is smaller than that between the toner and carrier in a two-component type developing agent.
Also, it is well known that the number of times of contact between the magnetic toner and the developing sleeve required for the magnetic toner to acquire a triboelectrification electric charge amount required for development varies depending on the composition of the magnetic toner, and the like.
Therefore, in the above-mentioned method, in a system which requires a larger number of times of contact to acquire a required triboelectrification electric charge amount, a phenomenon caused by charging instability tends to occur.
Furthermore, it is well known that the number of times of contact between the magnetic toner and the developing sleeve required for the magnetic toner to acquire a triboelectrification electric charge amount required for development varies depending on the composition of the magnetic toner, and the like.
Therefore, in the above-mentioned method, in a system which requires a larger number of times of contact to acquire a required triboelectrification electric charge amount, a phenomenon caused by charging instability tends to occur.
The present inventors examined electric charges generated by the one-component developing method, and found that the toner behaved as follows in an electric charge developed portion of the one-component developing method.
In FIG. 1, a developing device 20 comprises a toner container 3 for storing a magnetic one-component toner, a developing sleeve 1a which is arranged in the opening portion of the toner container 3 to be rotatable in the direction of an arrow in FIG. 1, and uses a non-magnetic member, a permanent magnet 1b fixed in the interior of the developing sleeve 1a, a magnetic blade 2 which is fixed to the toner container 3 and uses a magnetic member for regulating the thickness of a toner layer, and a toner convey member 4 arranged in the toner container 3. The magnetic blade 2 is arranged to have a constant distance value W from the developing sleeve 1a. In general, the distance is often set to fall within a range from 100 μm to 1 mm.
In the developing device shown in FIG. 1, a magnetic one-component toner is coated as a thin layer on the developing sleeve 1a. The thickness of the toner layer is determined by the position of a cut line L shown in FIG. 2.
According to the examinations of the present inventors, it was found that an electric charge was developed in a magnetic toner T when the magnetic toner T passed between the developing sleeve 1a and the magnetic blade 2. It was also found that the magnetic toner behaved as follows.
As shown in FIG. 3, planes perpendicular to a line connecting the developing sleeve 1a and the magnetic blade 2 are assumed, the plane closer to the magnetic blade 2 is represented by S1, and the plane closer to the developing sleeve 1a is represented by S2. In general, since the width of the magnetic blade 2 is set to be smaller than that of the permanent magnet 1b, the magnetic flux densities on the planes S1 and S2 are set, so that the magnetic flux density on the plane S1 becomes larger than that on the plane S2. Therefore, the magnetic toner T receives a force in the direction of an arrow in FIG. 3, i.e., a force toward the magnetic blade 2 side, between the developing sleeve 1a and the magnetic blade 2.
Therefore, as shown in FIG. 2, magnetic toner particles T form ears (state B), and these ears are formed from the magnetic blade 2 in the direction of the magnetic sleeve 1a. The magnetic toner T is charged as follows. That is, when the developing sleeve 1a contacts a toner particle t1 at the distal end of the ear formed from the magnetic blade 2, an electric charge is developed in the distal end.
Furthermore, it was found that the toner was conveyed as follows between the developing sleeve 1a and the magnetic blade 2.
As described above, since an electric charge is developed in the toner particle t1 at the distal end of the ear which contacts the developing sleeve 1a, a force in the direction of the developing sleeve 1a based on a reflection force acts on the toner particle t 1 , and a convey force in the rotational direction of the developing sleeve 1a acts on the toner particle t 1 by a frictional force with the developing sleeve 1a.
Since a given cohesive force acts between toner particles, a convey force also acts on a toner particle t2, which is in contact with the toner particle t1, via the cohesive force. Furthermore, a convey force via the cohesive force similarly acts on a toner particle t3 in an upper layer portion.
However, the magnetic force in the direction of the magnetic blade 2 acts on the toner between the developing sleeve 1a and the magnetic blade 2, as described above. Therefore, the toner ear is torn off at a position where the convey force acting on the toner overcomes the magnetic force, i.e., at the position of the cut line L in FIG. 2, and the toner particles remaining on the developing sleeve 1a are conveyed in the rotational direction of the developing sleeve 1a.
Therefore, as is apparent from the toner behavior and a process for developing an electric charge in the toner in the example using the magnetic blade, an electric charge can only be developed in toner particles near the developing sleeve 1a.
In the above-mentioned example, toner particles in which an electric charge is not developed conglomerate, as indicated by C in FIG. 2, and if this conglomerate of toner particles becomes large, the magnetic force continuously holding the toner particles on the magnetic blade 2 side weakens. For this reason, some toner particles in the conglomerated toner particles are conveyed in the rotational direction of the developing sleeve 1a. As a result, some toner particles conveyed on the sleeve 1a do not develop electric charges, and a phenomenon caused by charging instability tends to occur in the prior art.
In order to solve the above-mentioned problem, the present inventors proposed a developing device which can stably develop an electric charge in a magnetic toner by returning insufficiently charged magnetic toner particles into a developing container by a developing agent regulating member in Ser. No. 250,682.
More specifically, as shown in FIG. 4, as a member for regulating a toner layer coated on the developing sleeve 1a, a developing agent regulating member 6a, which consists of a non-magnetic member, is rotatably arranged near the developing sleeve 1a to face it. In the developing agent regulating member 6a, a permanent magnet 6b is arranged near a magnetic pole N11 of the permanent magnet 1b. Furthermore, a magnetic pole S61 of the permanent magnet 6b in the developing agent regulating member 6a faces the magnetic pole N11 of the permanent magnet 1b in the developing sleeve 1a, and the rotational direction of the developing agent regulating member 6a is set to be the same as that of the developing sleeve 1a. With this arrangement, magnetic toner particles which do not contact the surface of the developing sleeve 1a can be returned into the developing container, and only sufficiently charged magnetic toner particles can be conveyed, thus stabilizing a charging operation of the toner.
As described above, when the developing agent regulating member 6a, which includes the permanent magnet 6b therein, is rotatably arranged near the developing sleeve 1a, the charging operation of the magnetic toner can be stabilized.
However, in the above-mentioned proposal, a sufficiently wide latitude in the arrangement for coating only sufficiently charged magnetic toner particles onto the surface of the developing sleeve cannot often be assured depending on the combination of the magnetic pole N11 in the developing sleeve 1a and the magnetic pole S61 in the developing agent regulating member 6a, cohesion of magnetic toner particles, and the like.
Depending on the combination of the magnetic pole N11 in the developing sleeve 1a and the magnetic pole S61 in the developing agent regulating member 6a, or when the developing agent regulating member 6a consists of a magnetic member, and the width of the member 6a is set to be smaller than the width of the magnetic pole N11, if the rigidity of the developing agent regulating member 6a is low, then the developing agent regulating member 6a flexes by a magnetic force, resulting in coating nonuniformity of a toner layer.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a developing device which can convey only sufficiently charged toner particles to a developing region.
It is another object of the present invention to provide a developing device which can prevent flexure of a regulating member for regulating the toner amount due to a magnetic force.
It is still another object of the present invention to provide a developing device comprising: a toner carrier which moves while carrying a toner on a surface thereof; and a regulating member for regulating an amount of toner on the toner carrier by applying a moving force to the toner in a direction opposite to a moving direction of the toner carrier, wherein in a regulating portion defined by the regulating member, a moving force received by toner which is not in contact the surface of the toner carrier, from the regulating member, is larger than a convey force received from the toner carrier.
It is still another object of the present invention to provide a developing device comprising: a toner carrier which faces an image carrier for carrying an electrostatic latent image, and which rotates while carrying a toner on a surface thereof; and a regulating rotary member for regulating an amount of toner on the toner carrier by rotation, wherein a regulating portion of the regulating rotary member is arranged on a side of the regulating member opposite the image carrier with respect to a line in a direction of gravity which passes through the center of rotation of the toner carrier.
It is still another object of the present invention to provide a developing device comprising: a toner carrier, having a magnet therein, for carrying a magnetic toner; a regulating rotary member, having a magnet therein, for regulating an amount of toner on the toner carrier; and magnetic field generating means for applying, to the regulating rotary member, a magnetic force in a direction substantially opposite to a direction of a magnetic force received by the regulating rotary member from the magnet in the toner carrier.
Other objects of the present invention will become apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a conventional developing device;
FIG. 2 is an enlarged sectional view of a layer thickness regulating portion in the device shown in FIG. 1;
FIG. 3 is a view for explaining the concentration of a magnetic field in the device shown in FIG. 1;
FIG. 4 is a sectional view showing another conventional developing device;
FIG. 5 is a schematic view showing the arrangement of an image forming apparatus to which a developing device of the present invention can be applied;
FIG. 6 is a sectional view of a developing device according to a first embodiment of the present invention;
FIG. 7 is a sectional view of a developing device according to a second embodiment of the present invention;
FIG. 8 is an enlarged sectional view of a layer thickness regulating portion in the embodiment shown in FIG. 6;
FIG. 9 is a sectional view of a developing device according to a third embodiment of the present invention;
FIG. 10 is a sectional view of a developing device according to a fourth embodiment of the present invention;
FIG. 11 is a sectional view of a developing device according to a fifth embodiment of the present invention;
FIG. 12 is a sectional view of a developing device according to a sixth embodiment of the present invention;
FIG. 13 is a sectional view of a developing device according to a seventh embodiment of the present invention;
FIG. 14 is a sectional view of a developing device according to an eighth embodiment of the present invention;
FIG. 15 is a sectional view of a developing device according to a ninth embodiment of the present invention;
FIG. 16 is a sectional view of a developing device according to a tenth embodiment of the present invention;
FIG. 17 is a view showing the relationship among a sleeve, a regulating member, and a magnet in the embodiment shown in FIG. 16, and
FIG. 18 is a sectional view of a developing device according to an eleventh embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 5 is a schematic view of an electrophotographic image forming apparatus to which a developing device according to each embodiment of the present invention can be applied.
As an electrostatic latent image carrier, a drum-shaped electrophotographic photosensitive body constituted by coating a photoconductive layer on a conductive substrate, i.e., a photosensitive drum 15, is rotatably arranged. The photosensitive drum 15 is uniformly charged by a charger 12, and an electrostatic latent image is formed on the drum 15 by exposing an information signal using a light-emitting element 13 such as a laser. The electrostatic latent image is then visualized by a developing device 20. The visualized image (toner image) is transferred onto a transfer member 19 by a transfer charger 14, and the transferred image is fixed by a fixing device 16, thus obtaining a permanent image. Note that the residual toner on the photosensitive drum 15 after the transfer operation is removed by a cleaning device 11.
First Embodiment!
FIG. 6 is a sectional view of a developing device according to the first embodiment of the present invention.
Referring to FIG. 6, the developing device 20 has a developing sleeve 1a as a toner carrier (1), which faces the photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 6. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. Convey members 4a and 4b are arranged in the developing container 3 to be rotatable in the directions of arrows in FIG. 6 so as to convey a magnetic toner in the direction of the developing sleeve 1a. Furthermore, a developing agent (toner) amount regulating member 6 is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. Moreover, a scraper 7, which has one end contacting the toner amount regulating member 6, is attached to the developing container 3.
The toner amount regulating member 6 is constituted by a cylindrical non-magnetic member 6a and a permanent magnet 6b fixed inside the non-magnetic member 6a, and is arranged near the developing sleeve 1a at the upstream side in the rotational direction of the developing sleeve 1a with respect to a developing region D. The non-magnetic member 6a is arranged to be rotatable in the same rotational direction as that of the developing sleeve 1a, as indicated by an arrow in FIG. 6.
The permanent magnet 6b is designed to have at least one magnetic pole, which has a polarity different from that of at least one of the magnetic poles of the permanent magnet 1b arranged in the developing sleeve 1a.
The permanent magnet 6b is designed so that a magnetic pole (N1) in the permanent magnet 1b arranged in the developing sleeve 1a is close to and faces a magnetic pole (S4) of the permanent magnet 6b, which pole has a polarity different from that of the magnetic pole (N1).
Furthermore, the width of the magnetic pole (S4) of the permanent magnet 6b, which is arranged to be close to and to face the magnetic pole (N1) in the developing sleeve 1a is set to be smaller than that of the magnetic pole (N1) in the developing sleeve 1a, so that the magnetic flux density of a magnetic field formed between the magnetic poles (N1) and (S4) increases from the developing sleeve 1a toward the toner amount regulating member 6 side.
With the above-mentioned arrangement, a force based on a magnetic force from the developing sleeve 1a toward the toner amount regulating member 6 side acts on a magnetic toner T present between the toner amount regulating member 6 and the developing sleeve 1a.
In this embodiment, since the non-magnetic member 6a is rotated in the direction of the arrow in FIG. 6, which is the same as the rotational direction of the developing sleeve 1a, as shown in FIG. 6, a convey force from the toner amount regulating member 6 in the direction of the interior of the developing container 3 acts on the magnetic toner T on the basis of the force of the magnetic field, a frictional force with the non-magnetic member 6a, and a frictional force between magnetic toner particles.
As described above, magnetic toner particles T which contact the developing sleeve 1a are charged by an electric charge generated by triboelectric charging with the developing sleeve 1a, a force in the direction of the developing sleeve 1a based on a reflection force that acts on the electrically charged magnetic toner particles T, and a convey force in the rotational direction of the developing sleeve 1a that acts on the charged magnetic toner particles T due to a frictional force with the developing sleeve 1a.
Therefore, in the developing device 20 with the arrangement shown in FIG. 6, magnetic toner particles t1, contacting the developing sleeve 1a, of the magnetic toner T present in a toner amount regulating portion receive a convey force (F1S) acting from the toner carrier 1 depending on the triboelectric charge amount of the magnetic toner and a convey force (F2) acting from the toner amount regulating member 6 as principal forces of the convey force, as shown in FIG. 8.
Also, magnetic toner particles t2, which do not contact the developing sleeve 1a, receive a convey force (F1) acting from the toner carrier 1 and the convey force (F2) acting from the toner amount regulating member 6 via a cohesive force among magnetic toner particles as principal forces of the convey force.
Therefore, if the following relations are satisfied, magnetic toner particles conveyed to a developing region are only those which are sufficiently charged:
F1S≧F2 (1)
F1<F2 (2)
Although the arrangement which satisfies the above-mentioned relations varies depending on the characteristics of a magnetic toner, in this embodiment, when the magnetic flux density of the magnetic pole (S4) of the permanent magnet 6b, which is arranged to be close to and face the magnetic pole (N1) in the developing sleeve 1a, is set to be 800 Gausses, the magnetic flux density in the magnetic pole (N1) in the developing sleeve 1a is set to be 900 Gausses, the ratio between the widths (to be referred to as 50% values hereinafter for the sake of simplicity) of regions indicating the peak values of the magnetic flux densities of the magnetic poles is set to satisfy the following relation:
(50% value of magnetic pole S4)/(50% value of magnetic pole N1)≅0.8
and the width of the magnetic pole (S4) is set to be smaller than that of the magnetic pole (N1), so that the magnetic flux density of a magnetic field formed between the magnetic poles (N1) and (S4) increases from the developing sleeve 1a toward the toner amount regulating member 6 side.
It was confirmed that when a distance W between the toner amount regulating member 6 and the toner carrier 1 was set to be 1 mm, and the absolute value of the peripheral velocity of the developing sleeve 1a was set to be equal to that of the non-magnetic member 6a, a magnetic toner, which had a weight-average particle size of 5 μm or more, and contained 10% by weight or more of an internally added magnetic member, satisfied the above-mentioned conditions (1) and (2).
However, as described above, the convey force (F1) from the developing sleeve 1a, which acts on the magnetic toner in the regulating region, changes depending on the cohesive force of the magnetic toner, and the cohesive force of the magnetic toner depends on the amount of magnetic toner present in the toner amount regulating region (a region C in FIG. 6) formed between the toner amount regulating member 6 and the toner carrier 1.
Therefore, in order to stably satisfy the conditions (1) and (2), the magnetic toner amount in the regulating region must always be controlled to be an appropriate amount, and in order to control the amount of magnetic toner held in the regulating region, the amount of magnetic toner conveyed in the direction of the regulating region must be set to be equal to that of magnetic toner conveyed from inside to outside the regulating region.
Therefore, the arrangement for conveying the magnetic toner in the direction of the regulating region and conveying the magnetic toner from inside to outside the regulating region must be adopted. In this embodiment, by adjusting the strengths and arrangement angles of the magnetic poles (N1, S3) in the developing sleeve 1a and the strengths and arrangement angles of the magnetic poles (S4, N4) in the toner amount regulating member 6, the toner amount regulating region (the region C in FIG. 6) formed between the toner amount regulating member 6 and the toner carrier 1 is adjusted. In addition, the arrangement which satisfies the conditions (1) and (2) is adopted near the toner amount regulating member 6 inside and outside the regulating region, so that the convey force (F2) acting from the toner amount regulating member 6 on the magnetic toner serves as a principal force, thereby conveying the magnetic toner from inside to outside the toner amount regulating region.
Also, since a scraper portion for scraping the magnetic toner conveyed by the convey force (F2), which is received from the toner amount regulating member, from the toner amount regulating member using the scraper 7 is arranged outside the toner amount regulating region, a predetermined amount of magnetic toner circulates, as indicated by an arrow a in FIG. 6.
With the above-mentioned arrangement, the amount of magnetic toner conveyed into the toner amount regulating region C and the amount of magnetic toner conveyed from inside to outside the region can be controlled, and the conditions (1) and (2) can be stably satisfied.
In order to stabilize the control of the amount of magnetic toner conveyed into the toner amount regulating region C and the amount of magnetic toner conveyed from inside to outside the region, it is preferable that the magnetic toner scraped by the scraper 7 be not immediately conveyed by gravity in the direction of the regulating region C. Therefore, in this embodiment, the arrangement positions of the regulating region C, the toner amount regulating member 6, and the scraper 7 are adjusted, so that the direction of the convey force depending on gravity and acting on the magnetic toner does not point in the direction of the toner amount regulating region C in a region where the convey force received from the toner amount regulating member 6 substantially disappears, and the magnetic toner is no longer conveyed by the toner amount regulating member 6.
The present invention is not limited to the above-mentioned arrangement, and it is preferable that the magnetic flux densities and 50% values of the magnetic poles, the distance W between the toner amount regulating member 6 and the toner carrier 1, the peripheral velocities of the developing sleeve 1a and the non-magnetic member 6a, and the like be appropriately adjusted in correspondence with the characteristics of the magnetic toner used so as to satisfy the conditions (1) and (2).
As described above, since the developing device shown in FIG. 6 is arranged to satisfy the conditions (1) and (2), only sufficiently charged magnetic toner particles can be carried on the developing sleeve 1a, and can be conveyed to the developing region.
Second Embodiment!
The second embodiment of a developing device for an image forming apparatus according to the present invention will be described below with reference to FIG. 7. Note that since this embodiment has substantially the same arrangement as that of the first embodiment, a detailed description of the same portions will be omitted, and only the characteristic portions will be explained below.
As has been described in the description of the first embodiment, in order to stably satisfy the conditions (1) and (2), it is preferable that the magnetic toner scraped by the scraper 7 be not immediately conveyed in the direction of the regulating region C. Therefore, it is preferable that the convey force acting from the toner carrier 1 on the magnetic toner also substantially disappears near the scraper 7 portion. The convey force received by magnetic toner particles, which do not contact the toner carrier 1, from the toner carrier 1 is transmitted by contact among the magnetic toner particles, as described above. Therefore, when the magnetic toner particles near the scraper 7 portion are prevented from contacting the magnetic toner particles contacting the toner carrier 1 near the scraper 7 portion, the magnetic toner scraped by the scraper 7 is not immediately conveyed in the direction of the regulating region.
Therefore, in this embodiment, in the arrangement of the developing device of the first embodiment, a toner convey guide 10 is arranged near the scraper 7, so that the convey force acting from the toner carrier 1 on the magnetic toner also substantially disappears in a region where the convey force received from the toner amount regulating member 6 substantially disappears, and the magnetic toner is no longer conveyed by the toner amount regulating member 6.
With the above-mentioned arrangement, the amount of magnetic toner conveyed into the toner amount regulating region C and the amount of magnetic toner conveyed from inside to outside the region can be controlled, and the conditions (1) and (2) can be stably satisfied.
Third Embodiment!
The third embodiment of a developing device for an image forming apparatus according to the present invention will be described below with reference to FIG. 9.
Referring to FIG. 9, a developing device 20 has a developing sleeve 1a as a toner carrier (1), which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 9. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. Convey members 4a and 4b for conveying a magnetic toner in the direction of the developing sleeve 1a are arranged in the developing container 3 to be rotatable in the directions of respective arrows in FIG. 9. Furthermore, a toner amount regulating member 62 is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a.
The toner amount regulating member 62 is constituted by a rotatable permanent magnet 62a which has at least two magnetic poles, and a non-magnetic member 62b, which is arranged between the developing sleeve 1a and the permanent magnet 62a to separate them from each other. The toner amount regulating member 62 is arranged in the vicinity of a position between magnetic poles of the permanent magnet 1b arranged in the developing sleeve 1a.
The toner amount regulating member 62 is arranged near the developing sleeve 1a at the upstream side in the rotational direction of the developing sleeve 1a, and the permanent magnet 62a is arranged to be rotatable in the direction of the arrow in FIG. 9 opposite to the rotational direction of the developing sleeve 1a.
With the above-mentioned arrangement, a magnetic toner T present between the toner amount regulating member 62 and the developing sleeve 1a receives the convey forces as in the first embodiment from the permanent magnet 62a of the toner amount regulating member 62 and the developing sleeve 1a. Therefore, the same effect as in the first embodiment can be expected by appropriately adjusting the number of magnetic poles, and the magnetic flux densities and 50% values of the magnetic poles of the permanent magnet 62a, a distance W between the permanent magnet 62a and the developing sleeve 1a, the rotational speeds of the permanent magnet 62a and the developing sleeve 1a, and the like in correspondence with the characteristics of the magnetic toner used, so as to satisfy:
F1S≧F2 (1)
F1<F2 (2)
The arrangement which satisfies the above-mentioned relations varies depending on the characteristics of a magnetic toner. In this embodiment, it was confirmed that when the permanent magnet 62a had a four-pole arrangement, the magnetic flux densities of the magnetic poles were set to be 400 Gausses or higher, the 50% values of the magnetic poles had 30° or more in an angle, the distance W between the permanent magnet 62a and the toner carrier 1 was set to be about 1 mm, and the absolute value of the peripheral velocity of the developing sleeve 1a was set to be twice or more that of the permanent magnet 62a, a magnetic toner, which had a weight-average particle size of 5 μm or more, and contained 10% by weight or more of an internally added magnetic member, satisfied the above-mentioned conditions (1) and (2).
As has been described in the first embodiment, in order to stably satisfy the conditions (1) and (2), it is preferable that the magnetic toner which drops when the convey force received from the toner amount regulating member 62 substantially disappears be not immediately conveyed in the direction of the regulating region.
Therefore, in this embodiment, a toner convey guide 10 is arranged between the toner carrier 1 and the toner amount regulating member 62, so that the convey force acting from the toner carrier 1 on the magnetic toner also substantially disappears in a region where the convey force received from the toner amount regulating member 62 substantially disappears, and the magnetic toner is no longer conveyed by the toner amount regulating member 62.
With the above-mentioned arrangement, the amount of magnetic toner conveyed into the toner amount regulating region and the amount of magnetic toner conveyed from inside to outside the region can be controlled, and the conditions (1) and (2) can be stably satisfied.
Note that this embodiment is not limited to the above arrangement, and it is preferable that the arrangement conditions be appropriately adjusted to satisfy the conditions (1) and (2) in correspondence with the characteristics of the magnetic toner used.
As described above, since the developing device shown in FIG. 9 is arranged to satisfy the conditions (1) and (2), only sufficiently charged magnetic toner particles can be carried on the developing sleeve 1a and can be conveyed to the developing region as in the first embodiment.
In this manner, insufficiently charged magnetic toner particles can be prevented from being conveyed to the developing region, and only sufficiently charged magnetic toner particles can be conveyed to the developing region. Therefore, the problem associated with charging instability can be solved, and a high-quality image can be obtained.
Fourth Embodiment!
The fourth embodiment of the present invention will be described below with reference to FIG. 10.
Referring to FIG. 10, a developing device 20 has a developing sleeve 1a as a toner carrier, which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 10. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member 4 is arranged in the developing container 3 to be rotatable in the direction of an arrow in FIG. 10 so as to convey a magnetic toner in the direction of the developing sleeve 1a. Furthermore, a toner regulating member 6a is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3.
In this embodiment, a regulating portion defined by the toner regulating member 6a is arranged on the side opposite to the photosensitive drum 15 with respect to a line in the direction of gravity, which passes the center of the developing sleeve 1a, i.e., on the side of the developing container 3.
Also, the regulating portion is arranged above a line in the horizontal direction, which passes the center of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the widths (to be referred to as 50% values hereinafter for the sake of simplicity) of regions indicating values of 50% or higher with respect to the peak values of the magnetic flux densities of the magnetic poles is set to satisfy the following relation:
(50% value of magnetic pole S61)/(50% value of magnetic pole N11)≅0.8
and the width of the magnetic pole S61 is set to be smaller than that of the magnetic pole N11, so that the magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 changes to increase from the developing sleeve 1a toward the toner regulating member 6a side. Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 10, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of an arrow b in FIG. 10, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
Since the arrangement position of the toner regulating member 6a is set in the first quadrant (see FIG. 8) on a two-dimensional coordinate system having the center of the developing sleeve 1a as an origin, the direction of a convey force depending on gravity and acting on the magnetic toner is set not to coincide with the direction of a toner amount regulating region A in a convey path of the magnetic toner which is scooped up from the developing sleeve 1a side in the developing container 3 and is returned into the developing container 3 by the toner regulating member 6a, thereby stably returning insufficiently charged magnetic toner particles from the toner amount regulating region A into the developing container.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is stirred with the remaining toner portion by the convey member 4, and is conveyed along the surface of the developing sleeve 1a again to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 10.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a wide latitude in the arrangement for stably coating only a sufficiently charged magnetic toner layer on the surface of the developing sleeve, and conveying the toner to the developing region can be obtained.
Fifth Embodiment!
Referring to FIG. 11, a developing device 20 has a developing sleeve 1a as a toner carrier, which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 11. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. Furthermore, a toner regulating member 6a is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3.
In this embodiment, a regulating portion defined by the toner regulating member 6a is arranged on the side opposite to the photosensitive drum 15 with respect to a line in the direction of gravity, which passes the center of the developing sleeve 1a, and below a line in the horizontal direction, which passes the center of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the 50% values of the magnetic poles is set to satisfy the following relation:
(50% value of magnetic pole S61)/(50% value of magnetic pole N11)≅0.8
and the width of the magnetic pole S61 is set to be smaller than that of the magnetic pole N11, so that the magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 increases from the developing sleeve 1a toward the toner regulating member 6a side. Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 11, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of an arrow b in FIG. 11, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
Since the arrangement position of the toner regulating member 6a is set in the fourth quadrant on a two-dimensional coordinate system having the center of the developing sleeve 1a as an origin, the direction of a convey force depending on the gravity and acting on the magnetic toner is set not to coincide with the direction of a toner amount regulating region A in a convey path of the magnetic toner which is scooped up from the developing sleeve 1a side in the developing container 3 and is returned into the developing container 3 by the toner regulating member 6a, thereby stably returning insufficiently charged magnetic toner particles from the toner amount regulating region A into the developing container.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is stirred with the remaining toner portion by a convey member 4, and is conveyed along the surface of the developing sleeve 1a again to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 11.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a wide latitude in the arrangement for stably coating only a sufficiently charged magnetic toner layer on the surface of the developing sleeve, and conveying the toner to the developing region can be obtained.
Sixth Embodiment!
Referring to FIG. 12, a developing device 20 has a developing sleeve 1a as a toner carrier, which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 12. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member 4 is arranged in the developing container 3 to be rotatable in the direction of an arrow in FIG. 12 so as to convey a magnetic toner in the direction of the developing sleeve 1a. Furthermore, a toner regulating member 6a is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3.
Note that the toner regulating member 6a is arranged to be rotatable in the same direction of an arrow b as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the 50% values of the magnetic poles is set to satisfy the following relation:
(50% value of magnetic pole S61)/(50% value of magnetic pole N11)≅0.8
and the width of the magnetic pole S61 is set to be smaller than that of the magnetic pole N11, so that the magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 changes to increase from the developing sleeve 1a toward the toner regulating member 6a side.
In order to set a toner regulating region A at the upstream side in the rotational direction of the toner carrier from the opposing position between the developing sleeve 1a and the toner regulating member 6a, the magnetic poles N11 and S61 are arranged at the upstream side in the rotational direction of the toner carrier with respect to the opposing position.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 12, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of an arrow b in FIG. 12, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
Since the toner regulating region A is set at the upstream side in the rotational direction of the developing sleeve 1a with respect to the opposing position between the developing sleeve 1a and the toner regulating member 6a, insufficiently charged magnetic toner particles can be prevented from being conveyed to the opposing position and passing the opposing position by, e.g., the cohesive force among the magnetic toner particles.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is stirred with the remaining toner portion by the convey member 4, and is conveyed along the surface of the developing sleeve 1a again to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 12.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a wide latitude in the arrangement for stably coating only a sufficiently charged magnetic toner layer on the surface of the developing sleeve, and conveying the toner to the developing region can be assured.
Seventh Embodiment!
Referring to FIG. 13, a developing device 20 has a developing sleeve 1a as a toner carrier, which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 13. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. Furthermore, a toner regulating member 6a is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3.
Note that the toner regulating member 6a is arranged to be rotatable in the same direction of an arrow b as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the 50% values of the magnetic poles is set to satisfy the following relation:
(50% value of magnetic pole S61)/(50% value of magnetic pole N11)≅0.8
and the width of the magnetic pole S61 is set to be smaller than that of the magnetic pole N11, so that the magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 increases from the developing sleeve 1a toward the toner regulating member 6a side.
In order to set the arrangement position of the toner regulating member 6a in the fourth quadrant (see FIG. 8) on a two-dimensional coordinate plane having the center of the developing sleeve 1a as the center, and to set a toner regulating region A at the upstream side in the rotational direction of the toner carrier from the opposing position between the developing sleeve 1a and the toner regulating member 6a, the magnetic poles N11 and S61 are arranged at the inner side of the developing container 3 with respect to the opposing position.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 13, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of an arrow b in FIG. 13, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
Since the arrangement position of the toner regulating member 6a is set at the side opposite to the photosensitive drum 15 with respect to a line in the direction of gravity, which passes the center of the developing sleeve 1a, and below a line in the horizontal direction, the direction of a convey force depending on the gravity acting on the magnetic toner is set not to coincide with the direction of the toner amount regulating region A in a convey path of the magnetic toner which is scooped up from the developing sleeve 1a side in the developing container 3 and is returned into the developing container 3 by the toner regulating member 6a. In addition, the toner amount regulating region is set at the upstream side in the rotational direction of the developing sleeve 1a with respect to the opposing position between the developing sleeve 1a and the toner regulating member 6a. For these reasons, insufficiently charged magnetic toner particles can be stably returned from the toner amount regulating region A into the developing container 3, and can be prevented from being conveyed to the opposing position and passing the opposing position by, e.g., the cohesive force among magnetic toner particles.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is stirred with the remaining toner portion by a convey member 4, and is conveyed along the surface of the developing sleeve 1a again to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 13.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a wide latitude in the arrangement for stably coating only a sufficiently charged magnetic toner layer on the surface of the developing sleeve, and conveying the toner to the developing region can be warranted.
Still other preferred embodiments of the present invention will be described below.
Eighth Embodiment!
Referring to FIG. 14, a developing device 20 has a developing sleeve 1a as a toner carrier, which has a diameter of 32 mm, faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 14. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member 4 for conveying a toner in the direction of the developing sleeve 1a is arranged in the developing chamber 3 to be rotatable in the direction of an arrow in FIG. 14. Furthermore, a toner regulating member 6a having a diameter of 10 mm is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3. In addition, a planar permanent magnet 7 having one end facing the toner regulating member 6a is attached to the developing container 3.
The toner regulating member 6a is arranged to be rotatable in the direction of an arrow b1 which is the same as the direction of an arrow b2 as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the widths (to be referred to as 50% values hereinafter for the sake of simplicity) of regions indicating values of 50% or higher with respect to the peak values of the magnetic flux densities of the magnetic poles is set to satisfy the following relation:
{(50% value of magnetic pole S61)×(diameter of developing sleeve 1a)}/{(50% value of magnetic pole N11)×(diameter of toner regulating member 6a)}<1.0
The magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 increases from the developing sleeve 1a toward the toner regulating member 6a side.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The planar permanent magnet 7 has a magnetic pole S7 facing a magnetic pole N61 in the permanent magnet 6b, and a magnetic pole N7. The magnetic pole S7 is set to be 800 Gausses, and the magnetic pole N61 is also set to be 800 Gausses.
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 14, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of the arrow b1 in FIG. 14, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
In this embodiment, in order to prevent the toner regulating member 6a from being flexed by the magnetic force from the permanent magnet 1b, the magnetic pole S7 of the permanent magnet 7 is arranged at the position facing the magnetic pole N61 of the permanent magnet 6b in the toner regulating member 6a, and applies a magnetic force from the magnetic pole S7 in a direction opposite to that of the magnetic force from the above-mentioned permanent magnet 1b, thereby preventing the toner regulating member 6a from being flexed. As a result, a toner coating nonuniformity caused by flexure of the toner regulating member 6a can be prevented.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is attracted on the surface of the developing sleeve 1a by the magnetic force, and is conveyed to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 14.
The magnetic toner is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a along the surface of the developing sleeve 1a by the magnetic force in the developing container 3. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction to the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a toner coating nonuniformity caused by flexure of the toner regulating member 6a can be eliminated.
Ninth Embodiment!
Referring to FIG. 15, a developing device 20 has a developing sleeve 1a as a toner carrier, which has a diameter of 32 mm, faces a photosensitive drum 15 as the latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 15. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member 4 for conveying a toner in the direction of the developing sleeve 1a is arranged in the developing chamber 3 to be rotatable in the direction of an arrow in FIG. 15. Furthermore, a toner regulating member 6 having a diameter of 8 mm is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a, and a scraper 5 is attached to the developing container 3 to have one end contacting the toner regulating member 6. In addition, a planar permanent magnet 7 having one end facing the toner regulating member 6 is attached to the developing container 3.
The toner regulating member 6 is arranged to be rotatable in the direction of an arrow b1 which is the same as the direction of an arrow b2 as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole N11 in the developing sleeve 1a is set to be 900 Gausses, and the 50% value of the magnetic pole N11 is set to fall within a range from 40° to 60°, and the width of the toner regulating member 6 is set to be smaller than that of the magnetic pole N11. With this arrangement, the magnetic flux density of a magnetic field formed between the toner regulating member 6 and the magnetic pole N11 increases from the developing sleeve 1a toward the toner regulating member 6 side.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6 is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6 is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The planar permanent magnet 7 is arranged at the side opposite to the magnetic pole N11 to sandwich the toner regulating member 6 therebetween on a line passing the centers of the developing sleeve 1a and the toner regulating member 6, and its magnetic pole S7 is set to be 1,000 Gausses.
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 15, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6 side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6 acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6 side.
In this embodiment, since the toner regulating member 6 is rotated in the direction of the arrow b1 in FIG. 15, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6 by the magnetic force, receive a convey force from the toner regulating member 6 into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6.
In this embodiment, in order to prevent flexure of the toner regulating member 6 by the magnetic force from the permanent magnet 1b, the magnetic pole S7 of the permanent magnet 7 is arranged at the position facing the toner regulating member 6, and applies a magnetic force from the magnetic pole S7 in a direction opposite to that of the magnetic force from the above-mentioned permanent magnet 1b.
As a result, a toner coating nonuniformity caused by flexure of the toner regulating member 6 can be prevented.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6 by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is stirred with the remaining toner portion by the convey member 4, and is conveyed along the surface of the developing sleeve 1a again to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 15.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6 into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6 are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a toner coating nonuniformity caused by flexure of the toner regulating member 6 can be eliminated.
10th Embodiment!
Referring to FIG. 16, a developing device 20 has a developing sleeve 1a as a toner carrier, which has a diameter of 32 mm, faces a photosensitive drum 15 as the latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 16. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member 4 for conveying a toner in the direction of the developing sleeve 1a is arranged in the developing chamber 3 to be rotatable in the direction of an arrow in FIG. 16. Furthermore, a toner regulating member 6a having a diameter of 10 mm is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a. A permanent magnet 6b having a plurality of magnetic poles is fixed in the member 6a. Moreover, a scraper 5, which has one end contacting the toner regulating member 6a, is attached to the developing container 3. In addition, a planar permanent magnet 7 having one end facing the toner regulating member 6a is attached to the developing container 3.
The toner regulating member 6a is arranged to be rotatable in the direction of an arrow b1 which is the same as the direction of an arrow b2 as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole S61 in the permanent magnet 6b, which is arranged to be close to and face a magnetic pole N11 in the permanent magnet 1b located at the opposing position between the developing sleeve 1a and the toner regulating member 6a is set to be 800 Gausses, and the magnetic flux density of the magnetic pole N11 is set to be 900 Gausses. Also, the ratio between the 50% values of the magnetic poles is set to satisfy the following relation:
{(50% value of magnetic pole S61)×(diameter of developing sleeve 1a)}/{(50% value of magnetic pole N11)×(diameter of toner regulating member 6a)}<1.0
and the width of the magnetic pole S61 is set to be smaller than that of the magnetic pole N11, so that the magnetic flux density of a magnetic field formed between the magnetic poles S61 and N11 increases from the developing sleeve 1a toward the toner regulating member 6a side.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6a is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6a is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6a)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
In the planar permanent magnet 7, a magnetic pole S7 is arranged within a width of ±2 cm at the central portion, in the longitudinal direction, of the toner regulating member 6a to face a magnetic pole N61 in the permanent magnet 6b, as shown in FIG. 17. The magnetic pole N61 is set to be 800 Gausses, and the magnetic pole S7 is set to be 800 Gausses.
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 16, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6a side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6a acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6a. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6a side.
In this embodiment, since the toner regulating member 6a is rotated in the direction of the arrow b1 in FIG. 16, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6a by the magnetic force, receive a convey force from the toner regulating member 6a into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6a.
In this embodiment, in order to prevent the toner regulating member 6a from being flexed by the magnetic force from the permanent magnet 1b, the following arrangement is adopted.
Since a flexure caused by the magnetic force from the permanent magnet 1b becomes largest at the central portion of the toner regulating member 6a, the magnetic pole S7 of the permanent magnet 7 is arranged to face the magnetic pole N61 of the permanent magnet 6b in the toner regulating member 6a within the width of ±2 cm at the central portion, in the longitudinal direction, of the toner regulating member 6a, and a magnetic force from the magnetic pole S7 is applied to the central portion of the toner regulating member 6a in a direction opposite to that of the magnetic force from the above-mentioned permanent magnet 1b, thereby preventing the flexure of the toner regulating member 6a. As a result, a toner coating nonuniformity caused by the flexure of the toner regulating member 6a can be prevented.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6a.
A magnetic toner portion returned into the developing container 3 is scraped from the surface of the toner regulating member 6a by the scraper 5. The magnetic toner portion, which is returned into the developing container 3 in this manner, is attracted on the surface of the developing sleeve 1a by the magnetic force, and is conveyed to the opposing position between the magnetic poles N11 and S61. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 16.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6a. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6a into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6a are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction toward the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a toner coating nonuniformity caused by flexure of the toner regulating member 6a can be eliminated.
11th Embodiment!
Referring to FIG. 18, a developing device 20 has a developing sleeve 1a as a toner carrier which faces a photosensitive drum 15 as a latent image carrier via the opening portion of a developing container 3, consists of a non-magnetic metal member, and is rotated in the direction of an arrow in FIG. 18. A permanent magnet 1b having a plurality of magnetic poles is fixed in the developing sleeve 1a. A convey member for conveying a toner in the direction of the developing sleeve 1a is arranged in the developing chamber 3 to be rotatable in the direction of an arrow in FIG. 18. Furthermore, a toner regulating member 6 having a diameter of 8 mm is arranged in the vicinity of the developing sleeve 1a to extend in the same direction as the extending direction of the sleeve 1a.
A roller 9 is arranged adjacent to the toner regulating member 6, and a film 8 is looped between the roller 9 and the toner regulating member 6.
Note that the toner regulating member 6 is arranged to be rotatable in the direction of an arrow b1 which is the same as the direction of an arrow b2 as the rotational direction of the developing sleeve 1a.
In this embodiment, the magnetic flux density of a magnetic pole N11 in the developing sleeve 1a is set to be 1,000 Gausses, and the 50% value of the magnetic pole N11 is set to fall within a range from 40° to 60°, and the width of the toner regulating member 6 is set to be smaller than that of the magnetic pole N11. With this arrangement, the magnetic flux density of a magnetic field formed between the toner regulating member 6 and the magnetic pole N11 increases from the developing sleeve 1a toward the toner regulating member 6 side.
Furthermore, a distance W between the developing sleeve 1a and the toner regulating member 6 is set to fall within a range from 100 μm to 2 mm, and the ratio between the absolute values of the peripheral velocities of the developing sleeve 1a and the toner regulating member 6 is set to satisfy:
(Absolute value of peripheral velocity of toner regulating member 6)/(absolute value of peripheral velocity of developing sleeve 1a)>0.5
The film 8 comprises a 100-μm thick capton film, and is rotated in the direction of an arrow c upon rotation of the toner regulating member 6 in the direction of the arrow b1.
The magnetic toner has a weight-average particle size of 5 μm or more, and contains 10% by weight or more of an internally added magnetic member.
In the developing device with the arrangement shown in FIG. 16, since the magnetic flux density becomes higher from the developing sleeve 1a toward the toner regulating member 6 side, a magnetic force from the developing sleeve 1a toward the toner regulating member 6 acts on the magnetic toner present between the developing sleeve 1a and the toner regulating member 6. Therefore, magnetic toner particles which have a smaller reflection force with the developing sleeve 1a than the magnetic force and are not sufficiently charged are held at the toner regulating member 6 side.
In this embodiment, since the film 8 is rotated in the direction of the arrow c in FIG. 18, which is the same as the rotational direction of the developing sleeve 1a, magnetic toner particles, which are insufficiently charged and held on the surface of the toner regulating member 6 by the magnetic force, receive a convey force from the toner regulating member 6 into the developing container 3 on the basis of the force of the magnetic field and a frictional force with the surface of the toner regulating member 6.
In this embodiment, in order to prevent flexure of the toner regulating member 6 by the magnetic force from the permanent magnet 1b, the toner regulating member 6 is pulled by the film 8 in a direction opposite to the direction of the magnetic force from the permanent magnet 1b. As a result, a toner coating nonuniformity caused by flexure of the toner regulating member 6 can be prevented.
Therefore, insufficiently charged magnetic toner particles are not conveyed to the developing region beyond the opposing position between the developing sleeve 1a and the toner regulating member 6.
When a restriction force of the magnetic force disappears, the magnetic toner returned into the developing container 3 drops from the surface of the film 8 by its own weight.
A magnetic toner portion, which is returned into the developing container 3 in this manner, is attracted on the surface of the developing sleeve 1a by the magnetic force, and is conveyed to the opposing position between the magnetic pole N11 and the toner regulating member 6. The circulating path of the magnetic toner in the developing container 3 in this case is as indicated by an arrow a in FIG. 18.
The magnetic toner is charged by friction with the surface of the developing sleeve 1a in the developing container 3. The charged magnetic toner becomes attached to the surface of the developing sleeve 1a by a reflection force based on the electric charge of the toner itself, and is conveyed to the opposing position between the developing sleeve 1a and the toner regulating member 6. When the toner is conveyed to the opposing position, insufficiently charged magnetic toner particles are returned from the opposing position between the developing sleeve 1a and the toner regulating member 6 into the developing container 3 for the above-mentioned reason.
Therefore, magnetic toner particles which are conveyed to the developing region via the opposing position between the developing sleeve 1a and the toner regulating member 6 are only sufficiently charged magnetic toner particles, which have acquired a reflection force with the developing sleeve 1a, which exceeds the convey force in the direction to the interior of the developing container 3.
More specifically, according to the arrangement of this embodiment, a toner coating nonuniformity caused by flexure of the toner regulating member 6 can be eliminated.
The embodiments of the present invention have been exemplified. However, the present invention is not limited to these embodiments, and various modifications may be made within the spirit and scope of the invention.
|
A developing device for an image forming apparatus such as a copying machine, a printer, or the like to develop an electrostatic latent image on an image carrier includes a toner carrier which moves while carrying a toner on its surface, and a regulating member for regulating the amount of toner on the toner carrier by applying a moving force to the toner in a direction opposite to the moving direction of the toner carrier. In a regulating portion defined by the regulating member, a convey force received by a toner portion, which does not contact the surface of the toner carrier, from the regulating member is larger than a convey force received from the toner carrier.
| 6
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method of mounting, to a printed circuit board, an electronic component having connection leads or pins that extend from the electronic component.
2. Description of the Background Art
FIGS. 4A and 4B illustrate a conventional method of mounting an electronic component, for example, a flat-package IC, as disclosed in Japanese Patent KoKoKu Publication No. 60-58600. FIG. 4A is a plan view showing solder paste as it has been applied to a printed circuit board. FIG. 4B is an enlarged perspective view of section A, which is encircled by a broken line in FIG. 4A.
In the figures, reference numeral 11 denotes a printed circuit board; 14a and 14b denote pads arranged on the printed circuit board 11 to form four rows 24 parallel to the four sides of an electronic component such as a flat-package IC device, which is to be mounted and which is not shown. Pads 14b which are positioned at the ends of the rows 24 are wider than pads 14a. The pads 14a and the wide pads 14b are arranged at an equal interval or pitch so as to allow contact with connection leads projecting at an equal interval from each side of the electronic component. Element 15 is a strip of solder paste applied linearly, uniformly, and in the direction of each pad row 24.
An electronic component such as a flat-package IC device is mounted on the printed circuit board 11 in the following manner. First, solder paste 15 is applied in a strip across each pad row 24. Here, the solder paste is applied linearly, uniformly, and, so that a suitable amount may be applied, with its width adjusted in accordance with the dimensions of pads 14a, the dimensions of wide pads 14b, and the dimensions of connection leads protruding from the IC device to be mounted. Next, the IC device connection leads are bonded to the corresponding pads (pad 14a or wide pad 14b) by reflow soldering.
In reflow soldering, the previously applied solder paste 15 agglomerates (draws in together) on each pad upon melting and through an action of surface tension; by this, solder near one pad draws away from solder near adjacent pads. Afterwards, the solder solidifies, thereby binding or fixing the IC device to the printed circuit board 11.
However, this conventional method of mounting an electronic component has the following problems the amount of solder paste to be the amount of solder paste to be applied is determined in accordance with the dimensions of the pads and the dimensions of the connection leads of the component and is adjusted by adjusting the width of the strip of solder paste applied in advance. Consequently, if the width of the strip is made too large (i.e., if the amount of solder paste applied is excessive), an excess of solder paste may occur in components; and upon reflow soldering, the solder may not agglomerate sufficiently on top of a pad, thereby causing "solder bridging" and necessitating corrective work after soldering. On the other hand, if, in order to prevent the occurrence of solder bridging, the width of the solder is made too small, there may occur an insufficiency of solder.
Furthermore, there is often a need to position, between adjacent ends of pad rows orthogonal to each other, other circuit patterns; however, should the last pad in each pad row be a wide pad, it is often difficult to obtain space sufficient to dispose such other circuit pattern.
SUMMARY OF THE INVENTION
The invention seeks to solve the above problems and has as its purpose the attainment of a method for mounting an electronic component on a printed circuit board in such a way that an amount of solder suitable for the dimensions of the pads and the dimensions of the connection leads of the electronic component can be applied; unsuccessful soldering (insufficient solder, solder bridging, etc.) can be prevented; and placement of other circuit patterns is not obstructed.
The method of this invention is for mounting by reflow soldering, onto a printed circuit board, an electronic component having a plurality of connection leads protruding from that component, and includes the steps of:
applying a plurality of strips of solder on a group of pads arranged in a line on the printed circuit board, disposed in correspondence to said connection leads; and
bonding the connection leads of the electronic component to the corresponding pads by reflow soldering.
By the invention, the amount of solder applied can be optimized for the dimensions of the pads and the dimensions of the connection leads by adjusting the number of stripes of solder. As a result, solder bridging can be avoided.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitative of the present invention and wherein:
FIG. 1 is a perspective view showing a flat-package IC mounted on a printed circuit board in an embodiment of the invention;
FIG. 2 is a plan view showing solder paste as it has been applied to the printed circuit board of FIG. 1;
FIG. 3 is a plan view showing another embodiment of the invention;
FIG. 4A is a plan view showing solder paste as it has been applied to a conventional printed circuit board, and
FIG. 4B is an enlarged perspective view of section A, which is encircled by a broken line in FIG. 4A.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the invention will now be described below with reference to the drawings.
FIG. 1 is a perspective view showing a typical flat-package IC device mounted on a printed circuit board in an embodiment of the invention. FIG. 2 is a plan view showing solder paste as it has been applied to a printed circuit board in the embodiment of FIG. 1.
In FIG. 1, reference numeral 1 denotes a printed circuit board, 2 denotes an IC device, and 3 denotes connection leads or pins projecting from four sides of IC device 2 at an equal interval. Elements 14a and 14c are pads of the same shape which are provided on printed circuit board 1; these pads are arranged in four rows 34 on printed circuit board 1 which are parallel to the sides of the IC device 2 to be mounted on the printed circuit board 1. The pads 14a and 14c have an interval and arrangement corresponding to those of connection leads 3. The pads 14a and 14c are elongated in a direction at right angles to the direction of each pad row 34. In FIG. 2, continuous strips (in this example, two strips) of solder paste 5 are applied linearly, uniformly, and in the direction of each pad row 34.
Described below is a method of mounting an electronic component on a printed circuit board according to an embodiment of the invention.
First, solder paste 5 is applied linearly and uniformly in two strips across pad row 34 and in the direction of pad row 34. The number of strips of solder paste 5 to be applied as well as the width of each solder paste strips is determined in accordance with the dimensions of pads 14a, the dimensions the connection leads 3 of IC device 2, and the like, so that a proper amount of solder paste 5 is applied. Furthermore, strips of solder paste 5 are applied up to a certain distance projecting past outer ends 14d of pads 14c, situated on both ends of pad row 34. This distance or projection is equal to half of the spacing between adjacent pads. Next, connection leads 3 are placed in contact with the respective pads 14a and 14c, and reflow soldering, in which the solder is heated to be melted, is performed. By this, connection leads 3 are bonded to pads 14a and 14c; and IC device 2 is secured in place.
In the method of mounting described above, two strips of solder paste 5 melt during reflow soldering; the molten solder then agglomerates (draws in together) on pads 14a and 14c through an action of surface tension. By adjusting the number of strips of solder paste 5, one can apply an amount of solder paste 5 appropriate for the dimensions of the pads 14a and 14c and the dimensions of connection leads 3 of IC device 2.
Furthermore, by providing a plurality of strips of solder paste 5 as in the above embodiment, one can adjust, in accordance with the dimensions of pads 14a and connection leads 3, the width of the strips of solder paste 5 to a range within which no excess of solder occurs upon reflow soldering; thereby, solder will agglomerate sufficiently on the pads 14a and 14c, and solder bridges will not occur. On the other hand, an insufficiency of solder can be prevented by adjusting the number of strips of solder 5 as required to assure a suitable amount.
Furthermore, as for pads 14c on both ends of each pad row 34, by applying strips of solder paste 5 out past each outer end 14d of pad 14c over a distance equal to half of the spacing between adjacent pads, one can assure a suitable amount of solder paste 5 during reflow soldering; specifically, one can assure that, upon melting, solder paste 5, equal in amount to solder paste which agglomerates on pads 14a, agglomerates on pad 14c through an action of surface tension. In addition, there is no need to utilize a wide pad like that of the prior art; thereby, a relatively large gap S can be obtained in an area on printed circuit board 1 between adjacent ends of pad rows 34 orthogonal to each other; consequently, a relatively large space is provided in which to position another circuit pattern (not shown).
Described below is another embodiment of the invention.
FIG. 3 is a plan view of another embodiment of the invention. Structural elements identical to those of FIG. 1 are indicated with the same numeral. FIG. 3 shows solder paste as it has been applied to mount an IC device that has connection leads projecting from its sides at an incongruous spacing. In this embodiment, each pad row 34 parallel with each of the sides of the IC device 2 to be mounted comprises two groups of pads 36 and 38. The pad group 36 is made of up pads 16 arranged in a line at an equal interval. The pad group 38 is similarly made up of pads 18 in a line at an equal intervals. The interval at between pads 16 are different than the intervals between pads 18. A pair of strips 6 of solder paste are applied to the pad group 36. Another pair of strips 8 of solder paste are applied to the pad group 38. In other words, each pair of strips 6 or 8 of solder paste are applied over pad group 36 or 38 composed only of equally spaced pads 14a and does not extend to the other pad group 38 or 36. On both ends of each pad group 36 or 38, strips 6 or 8 of solder paste are applied out past each outer end of the pad at the end of each pad group, over a distance equal to half of the spacing between adjacent pads in the same pad group. It does not matter if the strips of solder paste of each pad group are in contact with the strips of solder paste of the other pad group, since the solder paste will agglomerate during reflow soldering. In other respects, this embodiment is the same as that described in reference to FIGS. 1 and 2.
In the embodiments described above, solder paste was as illustrative; however, the invention is not limited to the use of solder paste, formed solder and the like may also be used.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
|
In a method of mounting an electronic component onto a printed circuit board by reflow mounting, the electronic component having a plurality of connection leads protruding from the component, a plurality of strips of solder are applied on a group of pads arranged in a line on the printed circuit board. The pads are disposed on the circuit in correspondence to the connection leads, and the connection leads of the electronic component are bonded to the corresponding pads by reflow soldering. By applying solder in strips, their widths need not be excessive, thereby avoiding solder bridging.
| 7
|
STATEMENT OF GOVERNMENT INTEREST
[0001] The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.
BACKGROUND OF THE INVENTION
[0002] The memristor, or “memory resistor,” was first theorized by Leon Chua at the University of California-Berkeley in 1971[1]. Only theoretical for more than 30 years, researchers at Hewlett-Packard recently announced the discovery of memristors fabricated in their lab [2, 3]. In terms of its behavior, a memristor is a device whose resistance changes under given toggle conditions (e.g., exceeding some voltage) and then holds that resistance until another toggle condition is met. In this way, memristors can, be thought of as reconfigurable resistors with memory. However, given the nature at which Chua arrived at this particular switching property, relating charge (q) and flux linkage (φ), the memristor is a new fundamental electronic device in the same way resistors, capacitors and inductors are fundamental.
[0003] Memristors are promising devices for a wide range of potential applications from digital memory, logic and analog circuits, and even some bio-medical applications. Of particular interest for the invention described here memristors can also be applied in the development of neural networks. More specifically, memristor behavior is very similar to that of the synapses found in biological neural networks.
OBJECTS AND SUMMARY OF THE INVENTION
[0004] Treating nanoscale memristors as artificial synapses it becomes feasible to construct neuromorphic circuits dense enough to realize many applications such as image and voice recognition in hardware. The present invention uses memristors as artificial synapses in conjunction with a CMOS based neuron circuit that can be used in the construction of hybrid CMOS-memristor neuromorphic systems.
[0005] It is therefore an object of the present invention to provide an apparatus that behaves as a trainable neuromorphic circuit.
[0006] It is a further object of the present invention to provide an apparatus that weights and sums the outputs of a plurality of memristor-based artificial synapses into the input of a, neuron.
[0007] It is yet a further object of the present invention to provide an apparatus that trains a neuromorphic circuit through the application of externally-supplied signals.
[0008] It is yet still an object of the present invention to detect whether the output of a neuromorphic circuit matches an expected output, and to train said neuromorphic circuit to accomplish the same.
[0009] It is yet a further object of the present invention to provide a neuromorphic circuit that functions as a logic gate.
[0010] Briefly stated, the present invention provides an apparatus comprising a CMOS-memristor circuit which is constructed to behave as a trainable artificial synapse for neuromorphic hardware systems. The invention relies on the memristance of a memristor at the input side of the device to act as a reconfigurable weight that is adjusted to realize a desired function. The invention relies on charge sharing at the output to enable the summation of signals from multiple synapses at the input node of a neuron circuit, implemented using a CMOS amplifier circuit. The combination of several memristive synapses and a neuron circuit constitute a neuromorphic circuit capable of learning and implementing a multitude of possible functionalities.
INCORPORATED BY REFERENCE
[0000]
[1] L. O. Chua, “Memristor—the missing circuit element,” IEEE Trans. on Circuit Theory, vol. CT-18, no. 5, pp. 507-519, September 1971.
[2] D. B. Strukov, G. S. Snider, D. R. Stewart, and R. S. Williams, “The missing memristor found,” Nature, vol. 453, pp. 80-83, May 2008.
[3] R. S. Williams, “How we found the missing memristor,” IEEE Spectrum, vol. 45, no. 12, pp. 28-35, December 2008.
[4] J. Stine, I. Castellanos, M. Wood, J. Henson, F. Love, W. R. Davis, P. D. Franzon, M. Bucher, S. Basavarajaiah, J. Oh, and R. Jenkal, “FreePDK: An Open-Source Variation-Aware Design Kit,” in Proceedings of the 2007 IEEE International Conference on Microelectronic Systems Education, 2007.
[5] R. E. Pino, J. W. Bohl, N. McDonald, B. Wysocki, P. Rozwood, A. Campbell, A, Oblea, and A. Timilsina, “Compact method for modeling and simulation of memristor devices,” in Proceedings of IEEE/ACM International Symposium on Nanoscale Architectures , June 2010.
[6] G. S. Rose, R. Pino, and Q. Wu, “A Low-Power Memristive Neuromorphic Circuit Utilizing a Global/Local Training Mechanism,” in Proceedings of International Joint Conference on Neural Networks , San Jose, Calif., August 2011.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 depicts a CMOS-memristor neural circuit consisting of synaptic circuit (left) and a buffering stage (right) which amplifies the summed result of the synaptic circuits.
[0018] FIG. 2 depicts a schematic of two memristive synapse circuits driving a common CMOS neuron. The total charge from both inputs is summed at node V c and amplified at output V o .
[0019] FIG. 3 depicts the voltage output of the synapses (V c ) as a function of the weighted sum of the inputs, considering a two-input gate (see FIG. 2 ). Here a high voltage input of 250 mV is logic ‘1’ and a low voltage, 0V, is ‘0’. Each weighted input is the product of each logic value (0 or 1) and the respective memristance. The weighted inputs are then summed to obtain the weighted sum of memristance.
[0020] FIG. 4 depicts a schematic of n memristive synapse circuits driving a common CMOS neuron. Each “Synapse n” block contains the same memristive synapse circuits shown in FIG. 1 and FIG. 2 . The total charge from all inputs is summed at node V c and amplified at output V o .
[0021] FIG. 5 depicts the simulation results showing the use of three 3-input charge sharing neural circuits in the construction of a full adder.
[0022] FIG. 6 depicts the energy and delay for charge sharing neurons configured for Boolean logic.
[0023] FIG. 7 depicts the delay of a 4-input charge sharing neural circuit and the energy of a 4-input charge sharing neural circuit.
[0024] FIG. 8 depicts a single input neural circuit with one memristive synapse and a neuron. Also included is a feedback circuit used to train the memristor for some desired behavior.
[0025] FIG. 9 depicts an example 2-input CMOS-memristor neural circuit (based on FIG. 8 ) trained as an AND gate and then an OR gate.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] The present invention, an artificial neural circuit is constructed where memristors determine the weights of synapses that feed the CMOS based neural circuit.
[0027] Referring to FIG. 1 , a CMOS-memristor neural circuit 120 , a voltage divider circuit that acts as the memristive synapse. The value for the load resistance R L 10 (can also be accomplished with a pass transistor) must be properly chosen such that (1) the maximum voltage drop across the memristor never exceeds a toggle or threshold voltage at which the memristor M 20 will begin changing states and (2) the output voltage swing is maximized for the maximum possible change in memristance (R off −R on ), where R off and R on are the maximum and minimum resistance values for the memristor 20 , respectively. In other words, it is desired that the output to be very sensitive to the memristance without unintentionally changing the value of the memristance itself.
[0028] Still referring to FIG. 1 , consider a chalcogenide-material-based memristor 20 where the device memristance swings roughly between 200Ω and 1 kΩ and the threshold for the device to change memristance states is approximately +/−0.2V. For a small input voltage (V in ) 30 , the maximum drop across the memristor 20 will not approach or exceed +/−0.2V so the first criterion is satisfied. This small input voltage 30 can be guaranteed for sub-threshold operation where the supply voltage V DD 40 is held below the threshold voltage of the transistors. Furthermore, if a sub-threshold voltage is used for the supply then the load resistance R L 10 that maximizes the voltage swing can be determined by R L =√{square root over (R on ·R off )}.
[0029] The CMOS circuitry within the overall neural circuits must perform two major tasks: (1) amplify the voltage swing at voltage node V n (ΔV n ) 50 and (2) provide an output that can be summed together with the outputs of other synapses. The synaptic circuit shown in FIG. 1 achieves the above mentioned tasks through charge sharing.
[0030] Again referring to FIG. 1 , the summation circuit functions by allowing the pull-up PMOS transistor WP 60 to charge up the node V pu 70 between the two transistors when the input is 0V. Once charged, V pu 70 is held high until the input goes high which also produces a voltage at V n 50 (based on the memristance value) and turns on the driving NMOS transistor WN 80 . A high input voltage (V in ) 30 will also turn off the pull-up PMOS transistor WP 60 . The charge is then allowed to pass through the driving NMOS transistor WN 80 to increase the voltage V c 90 across the summation capacitance 100 . When V n 50 is less than the threshold voltage of the driving NMOS transistor WN 80 (high threshold variety) the transistor never turns on very strongly. Normally, the two floating capacitors at each internal node will charge to a common voltage. However, as V c 90 is charged it approaches the gate voltage V n 50 which causes the gate to source voltage of the driving NMOS transistor WN 80 to quickly approach zero. If the transistors are sized properly then the driving NMOS transistor WN 80 will turn off before charging is completed. Thus, the amount of charge and the associated voltage V c 90 is weighted according to the total memristance values M 20 at all inputs.
[0031] Still with reference to FIG. 1 , the value of the resistance R L 10 could be set to 477Ω The next design parameter is the voltage supply V DD 40 which is set to help maximize ΔV n . For the earlier example, V DD 40 can be set to 250 mV for 45 nm CMOS which also forces the circuit into sub-threshold operation. This leaves the sizing of the driving NMOS WN 80 and pull-up PMOS WP 60 transistors in the synapse circuit. The size of the pull-up PMOS transistor WP 60 should be tuned to (1) react quickly to changes at the input V in 30 and (2) provide enough internal capacitance at its drain to match the summation capacitance 100 at V c 90 and promote charge sharing. Assuming the drain capacitance of a transistor is approximately equal to the gate capacitance, the transistor width sizing of WP 60 should be equal to the total size of all input gates of the neuronal buffer or amplifier circuit 110 .
[0032] Turning to the buffering side of the circuit, it is important that the amplifier 110 be sensitive to changes at V c 90 . Furthermore, the output of buffer or amplifier circuit should be pulled strongly to either V DD 40 or ground depending on the input. Several options are possible for the buffer or amplifier circuit including a chain of CMOS inverters or a CMOS operational amplifier.
[0033] The final design parameter for the synaptic circuit 120 is the width of the driving NMOS transistor WN 80 in FIG. 1 .
[0034] Referring to FIG. 2 , considering the earlier example and the case where two synaptic circuits 130 drive a common summation capacitance 100 , FIG. 3 shows a plot of voltage V c (see FIG. 1 , 90 ) versus the weighted sum of the inputs and for a variety of width values for the driving NMOS transistor WN. (see FIG. 1 , 80 ) To clarify, the weighted sum is determined by multiplying the logic value at each input (e.g., ‘1’ for 250 mV and ‘0’ for 0V) by the corresponding memristance value M (see FIG. 1 , 20 ). The results in FIG. 3 were taken for a two input neural circuit, i.e., two synapses driving a single buffering circuit at node V 90 such that the weighted sum is the sum of the memristors driven by a high voltage. For example, if both inputs were 250 mV (logic ‘1’) and M 1 =1000Ω while M 2 =200Ω then the weighted sum would be 1200Ω. This being the case, the desired response is for V c 90 to be linear as a function of weighted sum of the inputs such that V c 90 reflects that summation. A further desire would be to have the V c 90 response centered around 125 mV (or half V DD ) to help reduce the required size of the first amplification stage.
[0035] Referring to FIG. 4 provides an example of how multiple synaptic circuits 130 can be connected and then buffered to produce an amplified version of the weighted sum of the inputs. As can be seen in FIG. 4 , the circuit consists of n synaptic inputs all driving node V c 90 . For example, considering how the inputs are weighed the total logically weighted sum would range from 0Ω to n·(1000Ω), if the memristance value for R off were 1000Ω.
[0036] Referring to FIG. 5 shows simulation results for three 3-input CMOS-memristor neural circuits configured to implement a majority logic full adder described. Specifically, the majority function Maj(A, B, C in ) of all three inputs A, B and C in is equivalent to the carry out C out term of a full adder. Furthermore, the sum can also be determined from a majority function as Maj(Maj( Ā, B , C in ), Maj(A,B, C in ), C out ) such that only three 3-input CMOS-memristor neural circuits are required to implement a full adder. As can be seen from FIG. 5 the circuit as configured functions as desired.
[0037] Considering all transistors to be fabricated using 45 nm CMOS and of the high threshold variety with V DD (see FIG. 1 , 40 ) set to 250 mV the energy consumption of the circuit is very low, on the order of femtojoules (fj) or 10 −2 joules according to SPICE simulation results utilizing the 45 nm predictive design kit (FreePDK) from Oklahoma State University [4] and memristor models developed at the Air Force Research Laboratory [5, 6]. The delay of the circuit is around 500 us.
[0038] Referring to FIG. 6 shows the performance of a single 3-input CMOS-memristor neural circuit mapped to implement several Boolean logic functions such as OR and AND functions. In addition to showing the performance, FIG. 6 also illustrates the ability to configure the CMOS-memristor neural circuit to implement a variety of logic functions. While such speeds may be on the order of what is observed for biological neurons, robust and even high performance operation will require massive parallelism.
[0039] Referring to FIG. 7 shows the delay and energy of the circuit depicted iii FIG. 6 as a function of the weighted sum of the four synaptic inputs.
[0040] Referring to FIG. 8 shows, as an example of training, an implementation of the CMOS-memristor neural circuit 120 from FIG. 1 but with additional circuitry that can be used for learning. The learning circuit used to train the memristors is designed such that circuit behavior eventually matches a given input signal expectation, V exp . Note that learning is made possible with two circuits: the global trainer and the local trainer. The global trainer exists for each neuron such that only one global trainer is required for several memristive synapse circuits. The purpose of the global trainer is to detect whether or not the output of the circuit matches some expectation. If the circuit does not produce the expected result, then the global trainer will send a signal (Sel G ) to all memristive synapses connecting to that neuron indicating training must occur. A local trainer is implemented for each synapse which takes the Sel G signal from the global trainer and if both Sel G and the respective input voltage V in are high then a high voltage training pulse is delivered across the memristor. During training, several clock cycles may be required to test the output and train the memristors to implement a particular function. So long as the memristors can be trained (i.e., they're not stuck on some particular state as a result of device failure) the circuit will eventually be trained to match the expected function regardless of what memristance states are actually used.
[0041] Still referring to FIG. 8 also allows training in both directions by controlling the polarity of the voltage drop across the memristor during the training phase. As can be seen in the figure, the memristor device is positioned between two voltages (V U and V D ) while training occurs. If V U is high and V D is low then the memristor is trained toward R on . On the other hand, if V U is low and V D is high then the drop across the memristor is negative and it is trained toward R off , the off state. It should also be noted that the signal V D can be set normally to a low value and acts as the ground rail during normal operation.
[0042] Referring to FIG. 9 and as an example of the learning process, a two input neural circuit is trained to function first as a Boolean AND logic gate and then as an OR logic gate is shown. This particular simulation is an example of an exhaustive supervised training session meaning the circuit is trained repetitively with every possible input/output combination until the output learns the desired expectation. As can be seen from the figure, the AND gate is implemented after two training cycles while the logical OR function requires three training cycles.
[0043] Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.
|
CMOS-memristor circuit is constructed to behave as a trainable artificial synapse for neuromorphic hardware systems. The invention relies on the memristance of a memristor at the input side of the device to act as a reconfigurable weight that is adjusted to realize a desired function. The invention relies on charge sharing at the output to enable the summation of signals from multiple synapses at the input node of a neuron circuit, implemented using a CMOS amplifier circuit. The combination of several memristive synapses and a neuron circuit constitute a neuromorphic circuit capable of learning and implementing a multitude of possible functionalities.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 60/485,104 filed Jul. 8, 2003, which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to structures, incorporating one-dimensional nanoelements and which are suitable for use in scanning probe microscopy, current injection applications, and other applications. “One-dimensional nanoelements” are structures, essentially in one-dimensional form, that are of nanometer dimensions in their width or diameter, and which are commonly known as nanowhiskers, nanorods, nanowires, nanotubes, etc. More specifically, but not exclusively, the invention is concerned with structures incorporating nanowhiskers, related production methods, and to methods of forming nanowhiskers.
BACKGROUND ART
[0003] The basic process of whisker formation on substrates, by the so-called VLS (Vapour-Liquid-Solid) mechanism is well known. A particle or mass of catalytic material, usually gold, is heated on a substrate in the presence of certain gases. The gases are absorbed by the catalytic mass to form an alloy. The alloy supersaturates, and a pillar of solidified material forms under the mass, and the mass rises up on top of the pillar. The result is a whisker of a desired material with the catalytic mass positioned on top. (See E. I Givargizov, Current Topics in Materials Science , Vol. 1, pages 79-145, North Holland Publishing Company, 1978.) The dimensions of such whiskers were in the micrometer range.
[0004] Although the growth of nanowhiskers catalyzed by the presence of a catalytic particle at the tip of the growing whisker has conventionally been referred to as the VLS (Vapour-Liquid-Solid process), it has come to be recognized that the catalytic particle may not have to be in the liquid state to function as an effective catalyst for whisker growth. At least some evidence suggests that material for forming the whisker can reach the particle-whisker interface and contribute to the growing whisker even if the catalytic particle is at a temperature below its melting point and presumably in the solid state. Under such conditions, the growth material, e.g., atoms that are added to the tip of the whisker as it grows, may be able to diffuse through a the body of a solid catalytic particle or may even diffuse along the surface of the solid catalytic particle to the growing tip of the whisker at the growing temperature. Evidently, the overall effect is the same, i.e., elongation of the whisker catalyzed by the catalytic particle, whatever the exact mechanism may be under particular circumstances of temperature, catalytic particle composition, intended composition of the whisker, or other conditions relevant to whisker growth. For purposes of this application, the term “VLS process”, or VLS mechanism, or equivalent terminology, is intended to include all such catalyzed procedures wherein nanowhisker growth is catalyzed by a particle, liquid or solid, in contact with the growing tip of the nanowhisker.
[0005] International Application Publication No. WO 01/84238 discloses in FIGS. 15 and 16 a method of forming nanowhiskers wherein nanometer sized particles from an aerosol are deposited on a substrate and these particles are used as seeds to create filaments or nanowhiskers.
[0006] For the purposes of this specification, the term nanowhiskers is intended to mean one-dimensional nanoelements with a diameter or cross-dimension of nanometer dimensions, preferably 500 nm or less.
[0007] Since the development of the Scanning Tunnelling Microscope in the 1980s there has been intense research in examining and processing surfaces at atomic dimensions by means of a tip of nanometer dimensions brought into close proximity or contact with the surface. The STM operates on a principle of a tunnelling current flowing between the tip and the sample surface, while moving the tip across the surface. Various other microscopes have been developed which operate on somewhat different principles for examining surfaces at the atomic level. These include, for example, the Atomic Force Microscope which relies on sensing of the electronic force of repulsion of the surface by means of a tip mounted on a flexible cantilever beam, microscopes which measure a magnetic force of attraction or repulsion by means of a magnetic tip, and microscopes which detect the heat generated by a sample surface, (see www.nanoworld.org). All of these microscopes fall into a generic class known as Scanning Probe Microscopes (SPM). For the purposes of this specification, the term Scanning Probe Microscope will be understood to include the Scanning Tunnelling Microscope, Atomic Force Microscope, and other microscopes which include a very fine tip moved over the surface of a specimen for determining characteristics of the surface on a nanometer or atomic scale.
[0008] The original form of STM comprised a tip mounted on a piezoelectric tube. The tunnelling current to a specimen surface was monitored, and the distance between the tip and the surface was adjusted to maintain the tunnelling current constant. Nowadays, the tip of such an STM commonly comprises a wire of Pt/Ir, the tip being formed by cutting and drawing the wire with cutters and pliers. Another common form of STM tip is a wire of Tungsten, whose end is etched. Both forms of tip have free ends with dimensions in the nanometer range.
[0009] A known construction of AFM uses a micromachined flexible cantilever beam of silicon with an integral silicon tip upstanding from the free end of the beam, the degree of flexure of the beam being measured as the tip is moved over the surface (see, for example, the McGraw Hill Encyclopaedia for Science and Technology 7 th Edition). The end of the tip commonly has dimensions in the nanometer range.
[0010] In Samuelson et al., Physica Scripta , vol. T42, pages 149-152, (1992), entitled “Tunnel-Induced Photon Emission in Semiconductors Using an STM”, there is shown in FIG. 6 an STM with a triangular semiconductor tip of gallium phosphide. Various types of tip material are proposed, as shown in FIG. 5 , to permit tunnelling current of P-type or N-type carriers for achieving photon emission in the semiconductor surface. This is done by providing a tunnelling current formed of a narrow band of low energy electrons, that may be injected resonantly with specific electronic state features (e.g. bandgap) of the semiconductor surface that is to be probed by this device.
[0011] Carbon nanotubes have been proposed for the tips of SPM, as by gluing a carbon nanotube to the end of the cantilever beam. However, adhesive may fail, particularly when the SPM is immersed in fluid. Furthermore, such SPM-tips will, in principle, suffer from the same limitation as a conventional metallic SPM-tip, with the simultaneous injection from a very broad band of electron states from the tip.
[0012] The use of nanotechnology in magnetic applications is well known. See, for example, U.S. Pat. No. 5,997,832 and WO 97/31139 to Lieber, which describe nanorods of various materials, some of which are magnetic. The use of nanotechnology to develop thin films for data storage applications is described in Shouheng Sun et al, Science Vol. 287, 17 March 2000, entitled “Monodisperse FePt Nanoparticles and Ferromagnetic FePt Nanocrystal Superlattices”. In the area of Spintronics, problems arise in the efficient injection of spin-polarised electrons into the Spintronics device. It has been proposed to use an SPM with ferromagnetic tip for such injections by a vacuum tunnelling process. (Wolf et al., Science Vol. 294, pages 1488-1495, Nov. 16, 2001, at page 1491.) See also Orgassa et al., Nanotechnology 12; pages 281-284, (2001).)
SUMMARY OF THE INVENTION
[0013] In a first aspect, the present invention provides a nanotechnological structure for use in a scanning probe microscope, comprising a tip member, and a nanowhisker projecting from a free end of the tip member, and being integral therewith.
[0014] There is thus provided a structure which may be used as a probe for a Scanning Tunnelling Microscope (STM), AFM, and other forms of SPM, with resulting technical advantages as set forth below. The tip member may be of any desired shape, for example tubular, conical or triangular. In a common form of STM, the tip member constitutes the end region of a metallic wire, and the nanowhisker may be formed on a prepared region at the wire end. Alternatively, the tip member may be formed as a separate member mounted on a substrate, or other appropriate support, depending on the intended application. Both the tip member and nanowhisker will usually be formed of conductive or semiconductive material, to permit current flow, but there may be circumstances where insulative material is employed, depending on the physical parameter used as a metric.
[0015] Measurements with STM are usually at the atomic scale for examining surface features in extreme detail. Measurements with AFM, on the other hand, are more commonly on a larger nanometer scale for examining engineered nanostructures. Where, as is commonly the case, the probe structure is intended for atomic force measurements, a tip support member may comprise a flexible elongate member or beam of predetermined dimensions and mechanical characteristics, in particular elasticity. The probe structure is then suitable for use in an Atomic Force Microscope (AFM). The tip member may be integral with the beam, where the beam is of a suitable material, e.g. silicon. Other forms of tip support member may be used, for example V-shaped support members.
[0016] More specifically therefore, the invention provides a nanotechnological structure, comprising a flexible support member, the support member having an upstanding tip member at or adjacent a free end of the support member, and a nanowhisker projecting from a free end of the tip member, and being integral therewith.
[0017] In a second aspect, the invention provides a method of forming a nanotechnological structure for a scanning probe, comprising:
providing a tip member; and forming a nanowhisker projecting from the tip member.
[0020] In a preferred embodiment, the formation of the nanowhisker includes:
providing at the free end of the tip member a mass of catalytic material of predetermined volume; and heating the mass and exposing the mass to gases of predetermined type under conditions such as to form, by the VLS process, a nanowhisker upstanding from the tip member.
[0023] It is possible and in accordance with the invention to have more than one nanowhisker formed at the end of the tip member. More than one tip member may be provided, each tip member having one or more nanowhiskers formed thereon. Such tip members may be mounted on a single support, or may be independently mounted for independent movement.
[0024] In at least one preferred embodiment of the invention, the tip member is mounted on a cantilever beam of silicon or other conductive or semiconductive material and has predetermined dimensions, usually in the micrometer range. The beam has predetermined mechanical characteristics, in particular a predetermined resilience in response to forces exerted on the end of the beam. The beam is formed with an upstanding tip member at its free end. Where the beam is of a suitable material such as Si, the tip member is formed integrally with the beam by a suitable process such as micromachining.
[0025] A nanowhisker is formed at the extreme end of the tip member and is preferably grown by the process described in our copending U.S. patent application Ser. No. 10/613,071 filed Jul. 7, 2003 and International Application No. PCT/GB03/002929, filed Jul. 8, 2003, the contents of which are incorporated herein by reference. An area of gold or other catalytic material is provided on the end of the tip member, as by a lithographic process, for example nanoimprint lithography (NIL), or by the deposition of a gold nanoparticle. When heated in epitaxy apparatus, the gold area coalesces and forms a catalytic melt. Gases introduced into the growth system are absorbed by the melt, and form a eutectic alloy. Upon supersaturation, a solidified material of desired composition, for example gallium arsenide, is deposited at the interface between the melt and the semiconductor crystal underneath. In this way a column is formed, and this column is termed a nanowhisker or nanowire.
[0026] A scanning probe microscope according to the invention has the feature that a very narrow energy distribution of injected carriers may be provided. A very accurate and sensitive tool for examination of a sample surface is therefore provided. This narrow energy distribution may be obtained by the use of a degenerately doped large band-gap semiconductor nanowire material (e.g. GaP, GaN, ZnO) that creates free electrons in the conduction band of the semiconductor, with an energy range of about 10 mev—this is essentially independent of the specific material. Alternatively, an even smaller energy distribution of about 1 mev may be obtained by the use of a designed resonant tunnelling structure in the nanowire, for example. A resonant tunnelling structure, consisting of a series of heterojunctions within the nanowire between materials of different bandgap, is fully described in our copending U.S. patent application Ser. No. 10/613,071 filed Jul. 7, 2003 and International Application PCT/GB03/002929, filed 8 July, 2003 , the contents of which are herein incorporated by reference, and is essentially formed by the process described above, but that the gas constituents are rapidly switched during the growth of the nanowire to produce segments of different material.
[0027] In either case, the nanowhisker may have a constant diameter cross-section along its length, or, as preferred, a tapering/conical shape. The desired shape is created by appropriate adjustment of growth conditions, principally temperature, as described in our copending U.S. patent application Ser. No. 10/613,071 filed Jul. 7, 2003 and International Application PCT/GB03/002929, filed Jul. 8, 2003.
[0028] The nanowhisker may be made of very precise dimensions, particularly in diameter where it can be accurately dimensioned to a dimension of just a few nanometers, that is less than 10 nm. In general, the diameter of the nanowhisker may be predetermined preferably within the range 5-50 nm. Its length may typically be chosen to be anything between about 100 nm to several micrometers. The nanowhisker thus formed constitutes an element of precise dimensions and predetermined characteristics in the probe tip structure. When it is formed integrally (monolithically) with the cantilever beam by the above process, it is very secure and reliable in use, and further has a perfect, continuous and impedance-less electrical coupling to the rest of the probe structure. This is in contrast to, for example, arrangements employing carbon nanotubes glued onto a beam where there is a risk of losing the tip, particularly when immersed in fluid, and further where a significant electrical impedance may exist between the nanotube and the SPM.
[0029] A melt of catalytic material, remaining at the top of the nanowhisker, may in some circumstances be undesirable; for example, it may affect the energy distribution of a stream of electrons passing through the nanowhisker, and the shape of the whisker end may not be especially well-defined. In accordance with a further aspect of the invention, therefore, the melt may be removed. In a preferred embodiment, using the techniques described in our copending U.S. patent application Ser. No. 10/613,071 filed Jul. 7, 2003 and International Application PCT/GB03/002929, filed Jul. 8, 2003, the growth of the nanowhisker may be completed, by appropriate change in growth conditions and substituting different gases in the reaction chamber, to terminate the growth with a short segment of a “sacrificial” segment of a material which is different from the major or adjacent part of the nanowhisker. For example, the sacrificial material may be InAs where the whisker is GaAs, or GaAs where the whisker is InAs. This sacrificial material may be later removed by a selective etching, hence removing the catalytic (e.g., gold) particle and forming a fresh surface which terminates the whisker. Further, the etching may produce a whisker end which is sharply rounded or pointed, for further precision.
[0030] In a further aspect, the invention provides a process of forming a nanowhisker, comprising:
providing a mass of catalytic material, and exposing the mass to one or more gases under predetermined operating conditions to form by the VLS process a nanowhisker; terminating the growth of the nanowhisker by changing at least one operating condition to provide at the end of the nanowhisker a segment of a different material from that of the remainder or at least an adjacent portion of the nanowhisker; and after formation of the nanowhisker, selectively etching the different material so as to remove the different material and the mass of catalytic material there above.
[0034] As an alternative to gold catalytic material, the catalytic material may comprise a group-III-metal such as Ga or In, which metal is comprised in the material from which it is intended to form the nanowhisker. The nanowhisker may be formed simply of the group-III-metal alone, or the metal alloyed with a group-V-material to form a semiconductor compound. In either case, the catalytic melt which remains at the free end of the nanowhisker after the nanowhisker is formed is the same material as that of the remainder of the nanowhisker, and this may be of advantage in some situations.
[0035] The present invention envisages use of probe structures in bio sensing applications. A bio sensing technique may be regarded as any sensor method which utilises bio molecules such as, inter alia, nucleic acid, proteins or antibodies or fragments, binding or amplification interactions being typical. A nanowhisker incorporated into an SPM tip, in accordance with the invention, may have a coating for binding predetermined molecules thereto, or the coating including biologically active molecules.
[0036] A nanowhisker incorporated into an SPM tip in accordance with this aspect of the invention is particularly adapted as a highly localised sensor for sensing parameters of biological molecules, e.g. DNA. For example, such molecules may be positioned on a substrate, and an AFM may be arranged to scan over the surface of the substrate, and map properties of the DNA. Further, the nanowhisker incorporated into the SPM tip may be formed of silicon or other oxidisable material. The nanowhisker is oxidised to form a surrounding layer of oxide along its length, but with the gold or other catalytic seed particle melt at the free end of the nanowhisker remaining free of oxide. This therefore provides a highly accurate probe for examining biological surfaces, where the interaction occurs within a precisely defined region. This permits mapping of molecules in a height direction, as well as planar directions, thus enabling a three dimensional XYZ mapping.
[0037] Further, and in accordance with the invention, a nanowhisker incorporated in an SPM tip may have a series of segments of different material along its length, such as to create between heterojunctions a light emitting diode of very small dimensions, for example, as small as 20 nm 3 . The wavelength of such a diode may be predetermined to a desired value by appropriate choice of materials and dimensions. Such diode, when appropriately energised, can be arranged to emit a single photon as and when required, and this can be employed to irradiate a biological sample (e.g. tissue, cell or molecule). The irradiation of biological samples with electromagnetic radiation is an extremely sensitive tool for determining optical absorbance of molecules, phosphorescence, luminescence, etc.
[0038] As regards magnetic applications, in the present invention, a probe tip structure having a nanowhisker is of use for current injection purposes into an electrical circuit, where the electrons forming the electric current should have precisely determined parameters of spin. For example, where the nanowhisker is formed of a magnetic material such as MnInAs, MnGaAs, MnAs, or a semimagnetic material, spin polarised electrons may be emitted from the tip of the whisker (a semimagnetic material is a semiconductor compound containing a dilute concentration of magnetic ions, e.g. Mn). Whilst the tip structure may be provided on any suitable support member, e.g. a rigid substrate or metal wire, it is preferred to use a cantilever beam construction, as the resilience of the beam gives a reliable contact, and the dimensions of the beam and tip structure are compatible with the dimensions of the circuit into which the electrons are injected.
[0039] As an alternative, the cantilever beam and tip member are formed of ferromagnetic material for polarising and alignment of the electron spins prior to the electrons entering the nanowhisker. The nanowhisker may then act as a conduit for the spin polarised electron stream. This may be an advantage where it is inconvenient to form the nanowhisker of a ferromagnetic material.
[0040] A further aspect of the invention is based on an array of nanowires or nanowhiskers formed of an appropriate magnetic material and employed as a data storage medium, wherein each nanowire may be selectively magnetised in a spin-up or spin-down condition to represent a “1” or “0” bit.
[0041] With regard to ferromagnetic properties, nanowhiskers may present a possibility for retaining ferromagnetism in very small regions. There is much interest in magnetic memory devices employing very small, typically single-domain, magnetic particles, or similar structures, as memory elements. However, it is known that as the size of a ferromagnetic single domain is reduced a limit is reached below which the ferromagnetic state cannot exist, and the domain, e.g., the single particle, assumes the superparamagnetic state in which the magnetic moments of all the atoms still line up to form the collective huge magnetic moment as in a ferromagnet, but where the orientation of this huge spin is no longer locked into a defined direction as it is in a ferromagnet. This limit is typically about 50 nm for a spherical magnetic particle. However, when a magnetic domain, e.g., a ferromagnetic domain, is incorporated into a nanowhisker, the diameter at which the domain ceases to be ferromagnetic and undergoes a transition to the superparamagnetic state can be reduced, because the substantially one-dimensional character of the nanowhisker tends to restrict the possible reorientation of the magnetic moment of the ions (or atoms) of the magnetic material. The material of the whisker can be made of iron, cobalt, manganese, or an alloy thereof. Other possible materials include manganese arsenide (ferromagnetic). Accordingly, it is possible to reduce the size of a ferromagnetic domain formed in a nanowhisker to less than the conventional lower limit for a particular material. Thus, ferromagnetic properties may be retained, at least for some magnetic materials, at transverse dimensions of 10 nm or less by forming them into nanowhiskers having a diameter of 10 nm or less. Such very small ferromagnetic elements have evident uses in the field of magnetic memory devices.
[0042] Thus it is possible in accordance with the invention to prepare smaller magnetic memory elements that can be selectively magnetized and produce a magnetic flux that can be sensed. The reduced symmetry in the nanowire (or nanowhisker) geometry may make possible a higher Curie temperature for magnetic semiconductor materials. Furthermore, the freedom in combining materials (inside a whisker) having different lattice constants may enhance the use of new magnetic semiconductors for these applications, such as MnGaP and MnGaN, which may have Curie-temperatures above room-temperature. Alternatively, metallic ferromagnetic materials including elements such as Fe, Co, Ni may be employed.
[0043] In general, the invention may be practised with a ferromagnetic material, a semimagnetic material (a dilute solution of magnetic ions in a semiconductor matrix), or other appropriate magnetic material, such as ferrimagnetic.
[0044] In a further aspect therefore, the present invention provides a nanowhisker comprising magnetic material, the diameter of the nanowhisker being such that a single ferromagnetic domain exists within the nanowhisker. Preferably the diameter of the nanowhisker is not greater than about 25 nm, preferably not greater than about 10 nm.
[0045] The nanowhiskers produced in accordance with the invention may be essentially cylindrical and have a constant diameter, or may have a slightly tapered form, depending on the precise nanowhisker growth conditions. Where the diameter is not strictly constant along the length of the nanowhisker, the diameter of the nanowhisker is to be regarded as an average value.
[0046] In a further aspect, the present invention provides a data storage medium comprising an array of nanoelements, preferably nanowhiskers, each including magnetic material, and read/write structure for selectively magnetising each nanowhisker in either of first and second magnetised directions and sensing the magnetised direction of each nanowhisker.
[0047] The sensing device preferably comprises an SPM type arrangement, with a cantilever support provided with a tip member and nanowhisker for providing a stream of spin-polarised electrons, as described above. Such tip structure (tip member and nanowhisker) may be moved across the array to scan the nanoelements, and may be selectively positioned in alignment with an element, in order to sense the direction of magnetisation. The impedance of the element to current flow provides an indication of magnetisation direction. The device for writing magnetisation direction may comprise the device for sensing, but wherein the magnitude of the spin polarised current is greatly increased to force the nanoelement into a desired magnetisation direction. Alternatively, a separate writing head may be provided which comprises, merely by way of example, a tip which can be strongly magnetised to selectively magnetise, by means of its magnetic field, the nanoelements.
[0048] In a further aspect, the invention provides a method forming a data storage medium, comprising:
forming volumes of catalytic material at predetermined sites on a substrate; and growing at each site, a nanowhisker of magnetic material and of such dimensions that only a single ferromagnetic domain exists within the nanowhisker.
BRIEF DESCRIPTION OF THE DRAWINGS
[0051] Preferred embodiments of the invention will now be described with reference to the accompanying drawings wherein:
[0052] FIGS. 1-1 f show steps in the process of formation of a tip for an atomic force microscope (AFM), forming a first embodiment of the invention;
[0053] FIGS. 2 a and 2 b show a second embodiment of the invention comprising a tip for a scanning tunnelling microscope (STM),
[0054] FIG. 3 shows a third embodiment of the invention adapted for determining properties of biological samples;
[0055] FIG. 4 shows a fourth embodiment of the invention comprising a nanostructure that forms a mechanism for current injection of spin polarised electrons into a Spintronics circuit;
[0056] FIGS. 5 a - 5 c show a fifth embodiment of the invention comprising an array of nanowhiskers of magnetic material forming a data storage medium; and
[0057] FIGS. 6 a - 6 e show a process for forming the nanowhisker array.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0058] Referring now to FIG. 1 a , a tip for an AFM comprises a beam of silicon 2 which is micro-machined (for example by etching) to form a rectangular elongate bar of a length, for example between 100 and 500 μm, and having a rectangular cross-section 50×5 μm. This provides a bar with a predetermined resilience to flexure. This resilience makes the structure suitable for use in an AFM. At one end of the beam 2 , a conical tip 4 is formed integrally with the beam, with a base 10 μm wide and a height of 20 μm. The extreme end 6 of tip 4 has a dimension about 20 nm across.
[0059] As shown in FIG. 1 b , a volume 10 of gold is affixed to the end 6 of the tip. A variety of techniques may be employed for carrying out this step. For example, the gold 10 may be electrolytically plated by immersing the end 6 in a solution containing gold ions and employing the tip as one electrode of a pair of electrodes, with a voltage applied between the electrodes. Alternatively, a beam of molecules may be directed at the end 6 , in molecular beam apparatus. The molecules are of organometallic type containing gold ions. Under appropriate operating conditions, the incident molecules fragment at the end 6 , with the gold ions bonding to the end 6 . As a further alternative, an aerosol droplet of gold may be affixed to the end of the tip by exposing the tip to such aerosol. Desirably a voltage is applied to the tip, to attract droplets via the electric field in the region of end 6 . None of these techniques is illustrated, since their implementation would be straightforward for a person skilled in the art.
[0060] After formation of the gold volume 10 on end 6 , the beam 2 is then moved into a Chemical Beam Epitaxy (CBE) apparatus 14 , FIG. 1 c . The beam is heated to a temperature of around 400° C. so that the gold melts and coalesces into a particle 12 . A beam of organic molecules containing gallium, TMGa (trimethylgallium) or TEGa (triethylgallium) is then injected into the source chamber 14 , and a gas containing arsenide ions, for example TBAs (tributylarsine) or AsH 3 , is introduced into the chamber. The TBAs material is decomposed by the high temperature employed whereas the group III molecules, TMGa or TEGa are broken down at the sample surface. In any event gallium and arsenic atoms are absorbed by the gold catalytic particle 6 to form a eutectic alloy. Upon further absorption, the eutectic alloy supersaturates and gallium arsenide is deposited between the particle 12 and the surface of the tip free end, whereby to form a nanowhisker column 16 . This process is more fully described in our International Application PCT/GB03/002929, filed 8 Jul. 2003. Depending on the temperature employed, the nanowhisker may be perfectly cylindrical, or, as preferred, it may be formed conically. The diameter of the nanowhisker depends on the initial area of the gold 10 and the resultant diameter of the particle 12 . The resultant AFM tip is shown in FIG. 1 d.
[0061] There is thus formed, as shown schematically in FIG. 1 d , a tip for an atomic force microscope or other microscopic instrument with the novel property that a very narrow energy distribution of injected carriers may be designed and controlled. This narrow energy distribution may be obtained by the use of a degenerately doped large band-gap semiconductor nanowire material (e.g. GaP, GaN, ZnO). that creates free electrons in the conduction band of the semiconductor, with an energy range of about 10 mev—this is essentially independent of the specific material. Alternatively, an even smaller energy distribution of about 1 mev may be obtained by the use of a designed resonant tunnelling structure in the nanowire. A resonant tunnelling structure, consisting of a series of heterojunctions within the nanowire between materials of different bandgap, is fully described in our Copending U.S. application Ser. No. 10/613,071 and International Application PCT/GB03/002929, filed 8 Jul. 2003, the contents of which are herein incorporated by reference, and is essentially formed by the process described above, but that the gas constituents are rapidly switched during the growth of the nanowire to produce segments of different material. This is shown schematically in FIG. 1 e , where the nanowhisker 16 comprises segments 17 of wide band gap material bounding a conductive segment 18 of low band gap material in order to form a resonant tunnelling diode (RTD).
[0062] In an alternative construction, the material of the segment 18 , and its width along the length of the nanowhisker, are selected in order to produce a light emitting diode of a particular wavelength, as more fully described with reference to FIGS. 15 and 16 of International Application PCT/GB03/002929, filed 8 Jul. 2003. The diode may be so small (20 nm 3 ) that it may be regarded as a point source, and the diode may be accurately controlled so as to be capable of emitting single photons “on demand”. This may be of use in mapping and scanning biological molecules, as described above.
[0063] In an alternative construction, as shown in FIG. 1 f , a short segment 20 of a sacrificial material such as InAs is formed at the end of a GaAs nanowhisker, by rapidly switching the constituents of the gas in the CBE chamber. A subsequent etching process with a suitable acid removes the segment 20 , and the gold particle melt 12 . The remaining nanowhisker 16 is of the same material throughout in this example (although it may include portions or segments of different materials), and has a well-defined end, the etching process producing a pointed or sharply rounded end 22 . The diameter of the wire at its end may be between 5 and 25 nm. Whilst the whisker could in principle be made of smaller diameter, it has been found that this range is suitable for the intended applications of an AFM. This construction is of advantage where it is necessary to have a well-defined stream of electrons flowing through the nanowhisker.
[0064] Although as described above, the AFM tip has a flexible cantilever beam, this is not strictly necessary for other applications, and a rigid substrate or other support member may replace the beam.
[0065] FIGS. 2 and 2 b show a probe for an STM according to a second embodiment of the invention. In FIG. 2 a , a support 24 mounts an STM tip structure comprising a metallic wire tip member 26 held in a holder 28 . The end of the wire 26 , as shown in FIG. 2 b , is tapered as at 30 . A nanowhisker 34 is formed at the end, in accordance with the processes described above with reference to FIGS. 1 b to 1 g . Since STM applications usually require measurements of an atomic scale, the nanowhisker may have a very small diameter, at least at its tip, say 10 nm or less, or even less than 5 nm.
[0066] Referring now to FIG. 3 , a third embodiment is shown comprising a tip structure of an AFM, with integral nanowhisker, where similar parts to those of FIG. 1 are denoted by the same reference numerals. A nanowhisker 36 is formed by the method described above. The whisker is formed of silicon and has a gold particle melt 12 at one end. Subsequent to formation of the whisker, the whisker is exposed to an atmosphere at a suitable temperature for oxidation of the silicon. This forms an outer shell 38 of silicon dioxide surrounding the whisker and extending along its length. The gold particle melt 38 remains in an unoxidised condition.
[0067] This therefore provides a structure highly suitable for precise examination of biological samples, since the region of interaction with the biological sample is very precisely defined. The nanowhisker 36 , 38 , 12 may be used, for example, to map properties of biological tissue in three directions of movement of the tip structure, X, Y, Z.
[0068] As an alternative, the whisker 36 may be exposed to an atmosphere of a suitable material for forming a high band gap material as an alternative to the oxidation layer 38 . The gold particle melt 12 may in either case be coated with an enzyme material or other biologically active material, in order to create desired reactions with biological samples.
[0069] In an alternative construction for three dimensional mapping and characterisation of biological tissue, a light emitting diode is formed within a nanowhisker 16 , 17 , 18 , as described above with reference to FIG. 1 e . The interaction of light with biological tissue provides a highly sensitive tool for characterising the tissue, particularly where the diode is so small (20 nm 3 ) that it may be regarded as a point source, and where the diode is capable of emitting single photons “on demand”.
[0070] Referring now to FIG. 4 , a fourth embodiment of the invention is shown for use in the field of Spintronics. Spintronics is a technical field where the properties of electronic devices rely on the transport of electron spin through the device. In FIG. 4 similar parts to those of FIG. 1 are denoted by similar reference numerals. A whisker 40 , formed at the end of the tip member 4 , by the process described above, is of a magnetic material (MnInAs, MnGaAs, MnAs) or semimagnetic material, containing a dilute concentration of Mn. Under an applied voltage V, spin polarised electrons 44 are emitted from the tip of the whisker, which makes electrical contact with an electrical contact 46 disposed on a substrate 48 . The spin polarised electrons 44 are injected by means of a tunnelling process into contact 46 and are then used for a desired function, such as reading the state of a magnetic memory element, such as nanopillar 49 disposed on substrate 48 and electrically connected by means of lower and upper electrical conductors diagrammatically shown at 50 L and 50 U respectively.
[0071] In a fifth embodiment, as shown in FIG. 5 a , a regular array of nanowhiskers 50 is formed on a substrate 52 . Only a small part of a practical array is shown in FIG. 5 a , and, for clarity, only the sites of many of the nanowhiskers are indicated. Each nanowhisker 54 is of a diameter 20 nm and is formed of a magnetic material (e.g. Fe, Co, Mn, MnAs, MnGaAs, MnInAs) which consists of a single ferromagnetic domain and may be in spin-up condition as shown in FIG. 5 b or a spin-down condition as shown in FIG. 5 c . When incorporated in a nanowhisker, in accordance with the invention, the domain diameter can be reduced because of the reduced possibilities for geometrical symmetrical alignment in a one-dimensional system, which makes it more difficult for the ions of the material to have more than one orientation. The material of the whisker can include iron, cobalt, manganese, or an alloy thereof.
[0072] The array 50 is arranged as a square matrix with rows and columns 56 , 58 . Each nanowhisker is 20 nm in diameter, and is spaced by a distance of 10 nm from adjacent nanowhiskers in row and column directions. In general, the spacing between adjacent nanowhiskers should be less than twice their diameter. This value represents a compromise between the requirement for the nanowhiskers to be as closely packed as possible, and a requirement that the nanowhiskers be sufficiently well spaced that they may be individually monitored. Instead of a rectangular matrix, the nanowhiskers may be arranged in any desirable configuration, such as a hexagonal lattice configuration (hexagonal close packed), or even a linear arrangement. A cantilever & tip arrangement 2 , 4 , 40 , similar to that of FIG. 4 , is employed as a read/write head which is movable over the array to scan the array in row and column directions X, Y. The head movement is controlled by conventional SPM techniques for selective positioning directly overhead in alignment with each nanowhisker.
[0073] In a read or sensing mode, the head 2 , 4 , 40 emits a weak current of spin-polarised electrons into the adjacent nanowhisker. The impedance of the nanowhisker to current flow provides an indication of magnetisation direction.
[0074] In a write mode, the magnitude of the current of spin polarised electrons emitted from the head is greatly increased and is sufficient, when flowing through the nanowhisker, to force the nanowhisker into a desired direction of magnetisation.
[0075] As regards the process of forming the array of nanowhiskers, gold catalytic areas are formed on substrate 52 by a NIL process at the desired sites of the nanowhiskers 54 . This is shown in FIGS. 6 a - e , which are sectional views of part of a row of sites. In FIG. 6 a , substrate 52 has formed on its upper surface a layer of deformable polymer 60 . The polymer has been deformed by a rigid stamp (not shown) to form rectangular depressions at the intended sites 62 of the nanowhiskers. The polymer is then etched, so as to remove the polymer in the site depressions 62 , and a layer of gold 64 is applied. The result is shown in FIG. 6 b , where the gold 64 makes contact with the substrate at the sites, and is elsewhere disposed on top of the remaining polymer 60 . Finally, as shown in FIG. 6 c , a further etching step removes the remaining polymer areas, to leave gold regions 66 at the nanowhisker sites 62 .
[0076] The substrate is then transferred to a epitaxial growth reaction chamber, where heat is applied to make the gold areas coalesce into particles 12 , as indicated in FIG. 6 d . Gases are introduced into the reaction chamber, and nanowires 54 are grown by the VLS process, FIG. 6 e . The nanowires are precisely formed, and are precisely located at the desired locations. If desired, a subsequent etching step may remove the gold particles at the end of the nanowires as previously described.
|
A probe structure for a scanning probe microscope comprises a nanowhisker ( 16,34 ) projecting from a free end of an upstanding tip member ( 4,26 ), and being formed integrally with the tip member. In another embodiment, a data storage medium comprises an array of nanowhiskers ( 54 ), each nanowhisker being formed from magnetic material, the diameter of the nanowhisker being such that a single ferromagnetic domain exists within the nanowhisker, preferably having a diameter not greater than about 25 nm and more preferably not greater than about 10 nm, and a read/write structure comprising the probe structure for injecting a stream of spin-polarised electrons into a selected nanowhisker of the array, either for sensing the direction of magnetisation in the nanowhisker, or for forcing the nanowhisker into a desired direction of magnetisation. When the probe nanowhisker is formed by a VLS process using a catalytic particle melt, the whisker may be formed with a sacrificial segment to allow for removal of the catalytic material by selective etching of the segment.
| 3
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application No. 61/451,277, which was filed Mar. 10, 2011 and is hereby incorporated by reference in its entirety.
BACKGROUND
[0002] The present disclosure relates generally to wellbore operations and, more particularly, to systems and methods of harvesting energy in a wellbore.
[0003] Power for use in a downhole environment has generally in the past been either stored in a device, such as a battery, and conveyed downhole or it has been transmitted via conductors, such as a wireline, from the space or another remote location. As is well known, batteries have the capability of storing only a finite amount of power therein and have environmental limits, such as temperature, on their use.
[0004] Electrical conductors, such as those in a conventional wireline, provide a practically unlimited amount of power, but require special facilities at the surface for deployment and typically obstruct the production flowpath, thereby preventing the use of safety valves, limiting the flow rate of fluids through the flowpath, etc., while the conductors are in the flowpath. Thus, wireline operations are typically carried out prior to the production phase of a well, or during remedial operations after the well has been placed into production.
[0005] In wellbore drilling operations, it is desirable to provide one or more efficient power sources downhole, for example, to power downhole instrumentation. A wide variety of devices may use mechanical energy in order to perform work downhole. Those devices may be subject to a variety of forces and may release energy in a number of ways. What is needed is a method of harvesting mechanical energy downhole and generating electrical power therefrom.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Some specific exemplary embodiments of the disclosure may be understood by referring, in part, to the following description and the accompanying drawings.
[0007] FIG. 1 is an illustration of an energy harvesting system, in accordance with certain embodiments of the present disclosure.
[0008] FIG. 2 is an illustration of another energy harvesting system, in accordance with certain embodiments of the present disclosure.
[0009] FIG. 3 is an illustration of an energy harvesting system showing embodiments where the magnetostrictive devices may be positioned at various angles to capture different flexure energies.
[0010] While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.
DETAILED DESCRIPTION
[0011] The present disclosure relates generally to wellbore operations and, more particularly, to systems and methods of harvesting energy in a wellbore.
[0012] Illustrative embodiments of the present disclosure are described in detail herein. In the interest of clarity, not all features of an actual implementation may be described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation specific decisions must be made to achieve the specific implementation goals, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of the present disclosure.
[0013] To facilitate a better understanding of the present disclosure, the following examples of certain embodiments are given. In no way should the following examples be read to limit, or define, the scope of the disclosure. Embodiments of the present disclosure may be applicable to horizontal, vertical, deviated, or otherwise nonlinear wellbores in any type of subterranean formation. Embodiments may be applicable to injection wells as well as production wells, including hydrocarbon wells. Devices and methods in accordance with certain embodiments may be used in one or more of wireline, measurement-while-drilling (MWD) and logging-while-drilling (LWD) operations.
[0014] In certain embodiments according to the present disclosure, magnetostrictive technology may be capable of generating electrical power during the process of drilling a borehole by using the mechanical energy generated in a bottom hole assembly. In certain embodiments, mechanical energy may be typically generated as a result of a variety of forces bearing on a bottom hole assembly section. For example, the bottom hole assembly section may be subject to varying tension, varying flexure of its components, and/or varying revolutions per minute of the drill bit due to the stick/slip action of the drill bit and/or stabilizer(s) contacting the borehole wall. The points in the bottom hole assembly where the mechanical energy is being generated varies during the drilling process. If no special provisions are made, mechanical energy generation may not occur at all, or may occur but at insufficient levels to generate the electric energy sought. Certain embodiments according to the present disclosure provide for special provisions to ensure sufficient mechanical and electrical energy is generated at a point where magnetostrictive technology is deployed.
[0015] Magnetostrictive materials have the ability to convert kinetic energy into magnetic energy that may be used to generate electrical power. Magnetostrictive materials have the property that, when strain is induced in the material, the change in linear dimensions produces a corresponding change in magnetic field about the material. In other words, mechanical loads can deform the material and thereby rotate magnetic domains. The change of the magnetic flux can be used to generate electrical power. A suitable material for the magnetostrictive material may be Terfenol-D, available from Etrema Products, Inc. Various materials, e.g., iron and iron alloys such as Terfenol, may provide suitable magnetostrictive and giant magnetostrictive responses. These materials normally respond to a force applied to their mechanical connection by creating a magnetic field which can be detected, for example, by a coil surrounding coil.
[0016] FIG. 1 is an illustration of an energy harvesting system 100 , in accordance with certain embodiments of the present disclosure. A length of pipe 105 may be part of a bottom hole assembly, such as a drill string, in a borehole. In a drilling environment, the pipe 105 may serve several purposes, including transmitting turning forces to a drill bit on the bottom of the drill string. An energy harvesting structure 110 may be coupled to the pipe 105 by upper collar 115 and lower collar 120 which are attached to the pipe 105 in any suitable manner. In various embodiments, the collars 115 and 120 may be removably attached or fixedly attached to the pipe 105 .
[0017] One or more magnetostrictive devices 125 may be mechanically coupled to the collars 115 and 120 by any suitable connections that allow transfer of forces from the collars 115 and 120 to the magnetostrictive devices 125 . Each magnetostrictive device 125 may include a magnetostrictive material surrounded by a wire coil. The magnetostrictive material may be in any suitable form and, in certain embodiments, may be in the form of a rod. The wire coil forms the electrical connection of the magnetostrictive device 125 . The magnetostrictive material may be made of iron or an alloy of iron with terbium and dysprosium, e.g., Terfenol-D, or any other material known to have magnetostrictive or giant magnetostrictive properties such as those listed above. The ends of the magnetostrictive material may be mechanically connected to the collars 115 and 120 .
[0018] Accordingly, with energy harvesting system 100 , one method of harvesting the mechanical energy and generating electrical power is by disposing one or more magnetostrictive devices 125 about a bottom hole assembly member that will flex during the drilling process. As the pipe 105 flexes and undergoes an initial strain, corresponding force may be transferred to the upper and lower collars 115 and 120 to cause resulting strain in the one or more magnetostrictive devices 125 . In response to that strain, the magnetostrictive material of a magnetostrictive device 125 may generate a magnetic field, and an electric current is produced in the coils of the magnetostrictive device 125 . Thus, as the pipe 105 repetitively flexes, the one or more magnetostrictive devices 125 produce corresponding repetitive electric currents.
[0019] The points in the bottom hole assembly where the energy is generated may vary during the drilling process. Bottom hole assembly modeling technology can be used to pinpoint the location(s) in the bottom hole assembly with the most deflection. Sensor technology may be deployed to measure the amount of energy at the flexible member, and drilling parameters may be adjusted in the unlikely case that not enough energy is being generated. By deploying an energy harvesting structure 110 with a flexible members at a point of the bottom hole assembly where mechanical energy is likely to occur, the likelihood of generating the sufficient energy is extremely high.
[0020] FIG. 2 is an illustration of an energy harvesting system 200 , in accordance with certain embodiments of the present disclosure. The energy harvesting system 200 may include a flexible member 210 , which, by way of example without limitation, may be incorporated in the form of the drill collar 205 where a section of the main body is machined away to have a diameter less than the rest of the drill collar 205 in order to make it more flexible. Because the scalloped portion of flexible member 210 makes it more flexible than other portions of the drill string, the flexible member 210 may localize the flexure in the drill collar 205 and drill string as a whole. The drill collar 205 may be coupled directly to a drill bit 235 as shown or indirectly (not shown).
[0021] An energy harvesting structure 215 may be coupled to the drill collar 205 by upper and lower collars 220 and 225 which are attached to the drill collar 205 . One or more magnetostrictive devices 230 may be mechanically coupled to the collars 220 and 225 by any suitable connections that allow transfer of forces from the collars 220 and 225 to the magnetostrictive devices 230 . The one or more magnetostrictive devices 230 may be implemented in similar manner to the magnetostrictive devices 125 discussed above. As the drill collar 205 flexes and undergoes strain, it will be readily appreciated that corresponding forces are transferred to the magnetostrictive devices 230 via the collars 220 and 225 , thereby inducing a resulting strain in the magnetostrictive material of the magnetostrictive devices 230 . In response to this strain, the magnetostrictive material generates a magnetic field and an electric current is produced in the coils of the magnetostrictive devices 230 . Thus, as the drill collar 205 repetitively flexes, the magnetostrictive devices 230 produces corresponding repetitive electric currents. Further deflection can be made to occur by the addition of a stabilizer at the top, or bottom of the drill collar 205 . This will also allow for ensuring the magnetostrictive technology containing casing around the collar will not actually contact the borehole wall during this process and sustain damage as a result of contact.
[0022] FIG. 3 is an illustration of energy harvesting system 200 showing embodiments where the magnetostrictive devices 230 may be positioned at various angles to capture different flexure energies. By way of example without limitation, the magnetostrictive devices 230 may be positioned axially as shown by magnetostrictive devices 230 A, radially as shown by magnetostrictive devices 230 B, and/or at a different angle as shown by magnetostrictive devices 230 C. Axial orientation may be particularly advantageous for harnessing flexure due to axial tension variations and variations in the weight on the drill bit. Radial orientation may be particularly advantageous for harnessing flexure due to varying revolutions per minute of the drill bit due to the stick/slip action of the drill bit. Other angles may provide a hybrid solution between axial and radial orientations. In certain embodiments, more than one flexible member 210 and energy harvesting structure 215 may be used in a given drill string.
[0023] In addition or in the alternative, certain embodiments of energy harvesting systems according to the present disclosure may be employed as a distributed torque indicator, and certain embodiment may be employed as a weight-on-bit indicator. By placing magnetostrictive elements and associated energy harvesting structures at particular points along the drill string, the torque corresponding to those particular points of the drill string may be determined by monitoring the varying output of each distributed magnetostrictive element. The outputs may be proportional to the torque each element experiences. Such monitoring may be important in determining various parameters, e.g., friction points in the drill string. Once determined, these points may be easily reamed, thereby saving drilling time. With respect to the weight-on-bit indicator, the output from a magnetostrictive element may be used to determine this very important parameter that may, for example, be used to determine ROB (rotation of bit) and other drilling characteristics.
[0024] Accordingly, certain embodiments of the present disclosure allow for harvesting mechanical energy downhole and generating electrical power therefrom. And even though the figures depict embodiments of the present disclosure in a particular orientation, it should be understood by those skilled in the art that embodiments of the present disclosure are well suited for use in a variety of orientations. Accordingly, it should be understood by those skilled in the art that the use of directional terms such as above, below, upper, lower, upward, downward and the like are used in relation to the illustrative embodiments as they are depicted in the figures, the upward direction being toward the top of the corresponding figure and the downward direction being toward the bottom of the corresponding figure.
[0025] Therefore, the present disclosure is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present disclosure. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. The indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces.
|
A system to harvest energy in a wellbore is disclosed. The system includes a flexible member disposed in a wellbore. The flexible member includes at least a portion of a drill string. The system includes an energy harvesting apparatus that includes magnetostrictive material and a conductor coupled to the magnetostrictive material. The energy harvesting apparatus is coupled to the flexible member to transfer forces from the flexible member to impart at least one of a strain or stress in the magnetostrictive material and to induce an electrical current in the conductor.
| 4
|
BACKGROUND OF THE INVENTION
The present invention relates to a feed control apparatus of a fabric feed device which drives directly a feed dog by a pulse motor controlled by open loop control system.
Conventionally, fabric feed devices for sewing machines obtain horizontal feeding motion of the feed dog by converting rotation of a main motor with a large torque into swinging motion. A converting mechanism for providing this swinging motion is constituted of a large number of parts such as a cam and a forked link, therefore a defect can result when a stitch pattern gets out of shape due to accumulated errors in the feed motion to be transmitted. Also, the conventional feed devices require a large space for installation in the bed of the sewing machine, resulting in a hindrance in making the sewing machine lighter and smaller.
Then, to eliminate the above-mentioned defect, an apparatus which drives a feed dog using a pulse motor as an independent driving source of the main motor is proposed and disclosed in the Japanese Patent Publication (examined) No. 57-30026. This apparatus detects each phase of rotation of an upper shaft and directly drives a pulse motor by an open loop control system in synchronism with the phase detection signal, thereby freely controlling feed motion of work fabric.
Control of the pulse motor by the open loop control system is performed by commanding the rotary angle of the pulse motor with reference to the number of steps or unit rotating motion. Accordingly, in operating the sewing machine, the pulse motor is set to an original or reference position once, and thereafter the number of command pulses is controlled assuming that the pulse motor is rotating in accurate response to the command pulses.
However, in a feed device employing a small-sized pulse motor with a small torque, an overload is applied to the feed dog due to forced feeding when starting the sewing machine or due to transfer of a thick part of work fabric, and thereby the pulse motor sometimes falls into step-out so as to be out of sync with respect to the reference position (loss of synchronism). If the pulse motor falls out of synchronism with respect to an initial reference position once, despite the fact that the relation between the rotary position of the pulse motor and the number of commanded steps is out of order, a controller gives command pulses assuming that the pulse motor is in synchronous state, and the feed dog is permitted to move within a predetermined range of horizontal feed motion and, therefore after the feed dog has reached the limit position and stopped, only the excited state of the pulse motor is changed and the pulse motor remains out of synchronism.
For this reason, once the pulse motor, which is out of sync due to overloading remains out of sync during continued operation. even after removal of the overload, and cannot give an accurate amount of horizontal feeding motion to the feed dog, therefore there remains a defect that the stitch pattern gets out of shape.
To prevent the above-described step-out non-synchronization of the pulse motor with respect to a reference position, a method is proposed wherein the overload to be applied to the feed dog is applied to the pulse motor through an escape spring without applying it directly to the pulse motor. However, in such a method, the pulse motor is required to rotate against a maximum tension of the spring without stepping-out. For this purpose, the maximum tension of the spring is required to be smaller than the step-out torque of the pulse motor. However, reduction in the spring constant means that the feed dog does not synchronize easily with the rotation of the pulse motor by a small external force, resulting in deterioration of the stitch pattern, and also means that the torque of the pulse motor is not used fully as a feeding force. Also, an increase in the step-out torque makes the pulse motor larger in size, raising a problem in weight and mounting.
In order to eliminate this defect, as described in U.S. Pat. No. 4,696,247, one of the inventors of the present invention proposed a feed device including a stopper disposed at a stoppage position corresponding to at least one of an upstream limit position and a downstream limit position of the horizontal feed motion of a feed dog. A feed control, having a excitation control, switches the excitation mode of a stepping motor which draws the feed dog to a specific excitation mode at least at the start and the end of the horizontal feed motion.
In the above-noted feed device, the stepping motor can be resynchronized to a reference position at the start-up of the sewing machine and during sewing operation. However, in the case where the asynchronous state of the stepping motor is induced by forceably feeding the fabric at the start-up of the sewing machine, feeding motion is carried out in the asynchronous state until the feed dot arrives at the downstream stoppage position. Therefore, the feed device cannot feed the fabric accurately.
Also in the case where the asynchronous state is induced by the feeding resistance due to a thick part of the fabric, feed motion is carried out in the asynchronous state until the feed dog arrives at the downstream stoppage point.
In order to solve the above-noted problems, at the start-up of the sewing machine, and after correcting an asynchronous state of the stepping motor, feeding motion should be carried out. Similarly, during sewing operation, after correcting an asynchronous state of the stepping motor at both the start or the end of the feed motion, continued feeding motion should be carried out. However, this patient publication does not disclose such a technical concept.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a feed control apparatus which automatically performs recovery from step-out state when the pulse motor, due to over load at the start-up of sewing operation and/or during consecutive sewing operation, is no longer synchronized with a reference position.
Another object of the present invention is to provide a feed control apparatus which permits use of a small-sized low torque pulse motor for feed motion.
In a sewing machine having a feed device driven with a pulse motor for feeding a fabric from an upstream location to a downstream location, a feed control apparatus according to the present invention comprises: a first stopper and a second stopper for defining an upstream side limit position and a downstream side limit position, respectively, in order to define the range of horizontal feed motion of a feed dog; first excitation control means to excite the pulse motor into a first predetermined excited state at the start or the end of feed motion when the feed dog is stopped at the first limit position; second excitation control means to excite the pulse motor into a second predetermined excited state at the end of feed motion when the feed dog is stopped at the second limit position; and sequence setting means for moving the feed dog to the second limit position in order to make the second excitation control means operative at the start-up of sewing operation, and for moving the feed dog to the first limit position in order to make the first excitation control means operative during subsequent sewing operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram showing a configuration in accordance with the present invention,
FIG. 2(a) and (b) are explanatory views for explaining functions of the present invention which show processes of feeding motions at start-up of a sewing machine and in continuous operation of the sewing machine in the state of out-of-step of a feed pulse motor,
FIG. 3 through FIG. 9 relate to a sewing machine whereto a feed device of preferred embodiment of the present invention is applied,
FIG. 3 is a perspective view showing an internal mechanism of the sewing machine,
FIG. 4 is an enlarged side view showing the state of feeding fabric by means of a presser foot and a feed dog,
FIG. 5 is a block diagram showing an electric configuration of the sewing machine,
FIGS. 6(a) through (c) are timing charts showing needle position signals and timing signals with respect to up-and-down motion of a needle,
FIGS. 7(a) through (c) are flow charts showing operation of the sewing machine,
FIGS. 8(a) and (b) are flow charts showing details of a feed control routine, and
FIGS. 9(a) through (c) are explanatory views showing processes of normal feeding motion and processes at start-up of the sewing machine and in continuous operation of the sewing machine in the state of out-of-step of the feed pulse motor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First of all, the inventive concept of the present invention will be described according to FIG. 1 and FIGS. 2(a) (b). The present invention has a basic configuration as shown in FIG. 1.
In synchronism with the motion of a needle driven up and down by a known needle up/down motion driving apparatus or drive means including a main motor, an up/down driving apparatus performs ascending and descending motions of a feed dog relative to the surface of a work supporting bed.
Feed controlling means controls a pulse motor operatively connected to the feed dog by an open loop contorl system for horizontal feeding motion of the feed dog, and repeatedly switches or pulses the pulse motor in sequence with a predetermined number P of pulses, and rotates the pulse motor by a unit angular amount S for each pulse.
The feed controlling apparatus comprises first and second excitation control circuits cooperating with first and second stoppers, respectively, and sequence setting circuits for preventing loss of synchronization of the feed dog with respect to the sewing needle due to an unintentional slippage of the pulse motor with respect to a reference location for positioning the shaft of the pulse motor known hereinafter as "stepping-out". The feed controlling apparatus eliminates stepping-out both at start-up and during continuous operation of the sewing machine. To define the range of horizontal feeding motion of the feed dog, first and second stoppers define a first limit position on an upstream feeding side of the work fabric and a second limit position on a downstream side opposite to the upstream feeding side, respectively, for stopping the feed dog of a member operatively connected thereto. A first excitation control apparatus controls the excited state of the pulse motor so that the excited state of the pulse motor at the start or end of horizontal feeding motion of the feed dog becomes a first predetermined specific excited state among the excited states into which the pulse motor is excited. This causes the pulse motor to rotate by an angular amount of P·S/2 from a specific position where it is positioned when the feed dog is defined at the first limit position by the first stopper. The second excitation control circuit controls the excited state of the pulse motor so that the excited state of the pulse motor at the end of horizontal feeding motion of the feed dog becomes a second predetermined specific excited state among the excited states into which the pulse motor is excited. This results in the pulse motor rotating by an angular amount of P·S/2 from a specific position where it is positioned when the feed dog is defined at the second limit position by the second stopper.
Sequence setting circuit moves the feed dog to the second limit position so that the second excitation control circuit can operate in the horizontal feeding motion when a sewing machine start command is generated from a sewing machine start/stop commanding circuit, and thereafter moves the feed dog to the first limit position so that the first excitation control circuit can operate in the subsequent horizontal feeding motion.
FIGS. 2(a) and (b) are views conceptually showing apsects of feeding motion of the feed dog of the feed control apparatus in accordance with the present invention. Symbols P1 through P11 show horizontal positions of the feed dog, and the pitch thereof corresponds to a unit amount of rotation S of the pulse motor. Then the excited states of the pulse motor include four states (P=4) as designated by symbols a, b, c and d, and the feed dog moves horizontally between the first limit position PA on the work fabric feeding side and the second limit position PB on the opposite side thereto, performing ascending an descending motions relative to the surface BS of the work supporting bed.
When the sewing machine start command is generated from the sewing machine start/stop commanding circuit to start sewing from the end part of the work fabric in the state that the feed dog protrudes above the bed surface BS and stops at the position P4, the pulse motor continues to be excited in the excited state d to hold the feed dog at the position P4. At this time, the operator moves the work fabric forcedly toward the second limit position PB (in the direction of forward feed) to insert the work fabric between the presser foot and the feed dog, and thereby the pulse motor steps out and the position thereof is changed by an amount of at least four times the unit amount of rotation S. For example, in the normal state, the feed dog is held at the position P4 as shown in a dash-colon line in FIG. 2(a), but in the case where the feed dog is displaced to the position P8 in the horizontal direction by step-out of the pulse motor, the sequence setting means command a seven-step movement from the position P4 to the position P11 assumming that the pulse motor is not in step-out state. According to this command, a horizontal feeding motion of a process HI is executed, but a three-step movement is commanded even after the feed dog has reached the position P11, and therefore the feed dog or the member operatively connected thereto contacts the second stopper disposed at the second limit position PB. Thereafter, the second excitation control circuit excites the pulse motor into the state c being the second specific state of excitation, and thereby a horizontal feeding motion of a process H2 is executed, and the feed dog is positioned accurately at the position P11. As a result, the state of a step-out due to feeding of the work fabric at starting of the sewing machine is eliminated.
The pulse motor restored to its normal and synchronized state moves the feed dog, and a horizontal feeding motion in the direction of retreat of a process H3 from the position P11 to the position P1 is executed. After the horizontal feeding motion of the process H3, the feed dog performs an ascending motion, and a forward feeding motion of a process H4 is executed. During the period of this horizontal feeding of the process H4, when an overload in the direction toward the first limit position PA is applied to the pulse motor due to transfer of the thick part of the work fabric or the like, the pulse motor falls into step-out and the position thereof is changed by an amount of at least four times the unit amount of rotation S as described above. For example, in the normal state, as shown by a dash-colon line in FIG. 2(b), in the case where a setting is made so that a horizontal feeding motion from the position P1 to the position P8 is performed, and the horizontal feeding motion of the process H4 from the position P1 to the position P4 is executed due to step-out of the pulse motor, the sequence setting circuit commands a seven-step movement from the position P8 to the position P1 assuming that the pulse motor is not in step-out state, According to this command, a horizontal feeding motion of a process H5 is executed, but a four-step movement is commanded even after the feed dog has reached the position P1, and the feed dog or the member operatively connected thereto contacts the first stopper disposed at the first limit position PA. Thereafter, the first excitation control circuit excites the pulse motor into the first specific excited state a, and thereby a horizontal feeding motion of a process H6 is executed, and the feed dog is positioned accurately at the position P1. Resultingly, the state of step-out generated due to transfer of the thick part of the work fabric in the continuous operation after the start of the sewing machine is removed.
As described above, the state of step-out of the pulse motor generated at the start and in the subsequent continuous operation of the sewing machine is automatically eliminated and the stitch pattern deterioration is reduced.
It follows from the detailed description above the feed control apparatus in accordance with the present invention has the configuration wherein the first and second stoppers for defining the first and the second limit positions of the feed dog, respectively, and the first and second excitation control circuits for exciting the feed pulse motor into predetermined phases to position the feed dog at predetermined positions in cooperation with those stoppers are installed, and the sequence setting circuit makes either of the first and second the second excitation control circuits operate in response to the case immediately after starting the sewing machine or the case where the sewing machine is in continuous operation, and therefore even in the case where either of the overload in the direction of forward feed at the start of the sewing machine and the overload in the direction of retreat feed in continuous operation of the sewing machine is applied to the feed dog, stepping-out of the feed pulse motor can be eliminated automatically, and the stitch pattern deterioration due to disorder of the feeding motion can be reduced. Also, the present invention enables a small-sized pulse motor with a small torque to be open-loop-controlled by a relatively simple and economical circuit configuration, and thereby enables the feed device for the sewing machine to be made smaller in size and lower in price.
Hereinafter, description is made on one embodiment in accordance with the present invention in reference to drawings.
FIG. 3 shows an internal mechanism of a sewing machine wherein a fabric feed device being one embodiment of the present invention is adopted, and the sewing machine is provided with a sewing machine frame 16 composed of a work supporting bed 10, a standard 12 erected on the work supporting bed 10 and an upper arm 14 extending horizontally from the standard 12. A main motor 18 disposed in the frame 16 is constituted so as to give a rotating force through a pulley driving belt 22 and a pulley (not illustrated) installed on an main shaft 20, and a pulley is connected to the main shaft 20 through a known clutch mechanism.
A needle bar stand 24 is journaled at the top end thereof, supporting a needle bar 26 so as to be movable up and down. The needle bar 26 is connected to the main shaft 20 through a take-up lever crank 28, a needle bar crank rod 30 and the like and performs reciprocating up-and-down motion according to rotation of the main shaft 20. A needle 32 is attached to the bottom end of the needle bar 26. One end of a swing connecting rod 34 is connected to the bottom end of the needle bar stand 24 to swing the needle bar stand 24 in the lateral direction, and the other end thereof is connected to the intermediate part of a sector gear 36, and the sector gear 36 is journaled at the top end thereof being constituted so that the toothed part thereof engages with a gear 40 attached to an output shaft of a needle swinging pulse motor 38. The swing range of the sector gear 36, that is, the swing range of the needle 32 is set by a V-shaped stopper assembly 42. A feed stand 46 carrying and supporting a feed dog 44 is installed, and the front forked ends of the feed stand 46 engage with a pin on an up/down feed arm 48, and the up/down feed arm 48 is fixed to an up/down feed shaft 50. A swing member 54 whereto a cam 52 engaging with the forked parts of the up/down feed shaft 50 is fixed is constituted so that rotation of the main shaft 20 is transmitted as a swinging motion through a crank rod 56. In this embodiment, the up/down feed arm 48, the up/down feed shaft 50, the swing member 54, the crank rod 56 and the like constitute a feed dog up/down motion driving apparatus.
The rear end of the feed stand 46 is supported rotatably by a pair of arms protruding on a horizontal feed shaft 58, and the horizontal feed shaft 58 is supported by the machine frame 16 so as to be able to swing around the shaft axis of its own. A sector gear 60 is fixed to the right end of the horizontal feed shaft 58, and the toothed part thereof is constituted so as to engage with a gear 64 fixed to an output shaft of a feed pulse motor 62. To define the range of horizontal feeding motion of the feed dog 44, a V-shaped stopper assembly 66 is installed in a fixed fashion, and the stopper assembly 66 has a first stopper 68 disposed at the position corresponding to a first feed limit position PA on the work fabric feeding side (front side) and a second stopper 70 disposed at the position corresponding to a second feed limit position PB on the rear side the first stopper 68 being located upstream from the second stopper 70.
In addition, the first stopper 68 may be installed in the vicinity of the first feed limit position PA, or may directly catch the feed dog 44 to define the first feed limit position PA.
Likewise, the second stopper 70 may be installed in the vicinity of the second feed limit position PB, or may directly catch the feed dog 44 to define at the second feed limit position PB.
Although omitted in FIG. 3 for convenience sake, as shown in FIG. 4, a presser foot 74 is attached to the bottom end of a presser bar 72 which can ascend or descend behind the needle 32, and the feed dog 44 can give horizontal feeding motion to a work fabric W in cooperation with the presser foot 74. Also, in the sewing machine of this embodiment, the needle swinging pulse motor 38 and the feed pulse motor 62 are constituted so as to be changed in sequence to the four states of excitation a, b, c and d to step, and particularly the feed pulse motor 62 can position the feed dog 44 at each of the positions P1 through P11 as shown in FIG. 9.
Next, description is made on an electric configuration of the sewing machine in reference to FIG. 5.
A needle position detector 80 detects the position of the tip of the needle 32 making up-and-down motion as shown in FIG. 6(a), and is constituted so as to generate a needle position signal UD which, as shown in FIG. 6 (b), has high level while the tip of the needle 32 is positioned above a predetermined position above the surface BS of the machine bed, and has low level while the tip is positioned below the predetermined position. A timing signal generator 82 is installed to determine the timing of reading out data from a stitch pattern data memory 94 as described later, and is constituted so as to generate a timing signal TS which has a high level temporarily when the tip of the needle 32 reaches a predetermined position above the machine bed surface BS as shown in FIG. 6(c).
A stitch pattern selecting apparatus 84 comprises a manual operating unit operative for selecting a desired stitch pattern from among a large number of stitch patterns and is constituted so as to generate a stitch pattern code signal SPC corresponding to the stitch pattern selected by operating the unit. A sewing machine start/stop commanding apparatus 86 comprises an operative unit operable for commanding operation and stop of the main motor 18 and is constituted so as to generate a command signal MC according to the operation of the unit. A main motor controlling apparatus 88 operates a main motor driver 90 according to a signal commanding the speed of the main motor 18 and the command signal MC, and controls the amount of electric power supplied to the main motor 18.
A stitch forming controlling apparatus 92 is installed to control stitch forming operation in the sewing machine, and is constituted so as to receive the above-described timing signal TS, needle position signal UD, stitch pattern code signal SPC and command signal MC as input signals, to read out data from a stitch pattern data memory 94 and to control a pulse motor driver 96, also being constituted so as to execute processing operations according to flow charts as shown in FIGS. 7 and 8. The stitch forming controlling apparatus 92 comprises an address counter performing addressing of the stitch pattern data memory 94, internal registers R1 and R2, and registers for storing various flags.
Also, the stitch pattern data memory 94 stores stitch pattern data consisting of needle swing data on the swing position of the needle 32 and feed data, on the amount of horizontal feed of the feed dog 44 and the direction of feed thereof to determine the position of stitch forming for each of a large number of stitch patterns, and is constituted so as to output the stitch pattern data in the address specified by an address counter in the stitch forming controlling apparatus 92 to that controlling apparatus 92. In addition, for stitch patterns formed by the sewing machine of this embodiment, practical stitch patterns for which only the forward feeding motion from the first feed limit position PA (front side) to the second feed limit position PB (rear side) is used are selected for convenience sake.
Description is made on operations of the sewing machine constituted as described above in reference to FIG. 7 through FIG. 9.
First, when power to the sewing machine is turned on, step ST1 as shown in FIG. 7(a) is executed to initialize the stitch forming controlling apparatus 92. For example, for initialization thereof, an operation setting the address counter to the head address for straight line stitches, an operation clearing the internal registers R1 and R2, and an operation clearing registers for flags FR, HN and FN and the like are executed. Thereafter, the level of a needle position signal UD is checked in step ST2. Normally, the needle 32 is positioned above the bed surface BS when the sewing machine is stopped, and therefore steps ST3 and ST4 are executed in sequence. By executing these steps ST3 and ST4, the needle swinging pulse motor 38 is driven until the sector gear 36 contacts the end determined as an original position stopper out of both ends of the stopper assembly 42, and a predetermined phase out of two excitation phases to be excited during a two-step movement from the original position stopper is excited, and origin setting of the pulse motor 38 is performed.
The stitch forming controlling apparatus 92 detects a change in the stitch pattern code signal SPC from the stitch pattern selecting apparatus 84, and thereby discriminates the selected stitch pattern in step ST5. In discriminating the selected stitch pattern, the head address corresponding to the selected stitch pattern is set in the address counter, and origin setting of the needle swinging pulse motor 38 is executed in steps ST7 and ST8 likewise the above-described steps ST3 and ST4. Then, in step ST9, the address counter address-specifies the stitch pattern data memory 94 and reads out a first stitch pattern data on the selected stitch pattern, the needle swinging pulse motor 38 is driven according to the needle swing data in that stitch pattern data, and thereby the swing position of the needle 32 at the first stitch is determined. Thereafter, in step ST10, the stitch forming controlling apparatus 92 detects whether or not the command signal MC from the sewing machine start/stop commanding apparatus 86 has changed to the high level showing start-up of the sewing machine, and when it detects a change to the high level, processing proceeds to step ST11 shown in FIG. 7(b), and the content of the flag FR is discriminated.
As shown in FIG. 7(b), immediately after power to the sewing machine has been turned on, since the flag FR has been reset in step ST1, reset of the flag FR is discriminated in step ST11, and step ST12 is executed. In step ST12, the level of the needle position signal UD is discriminated, and processing proceeds to step ST13 when the needle 32 is positioned below the bed surface BS to form the first stitch, and when the needle 32 is positioned above the bed surface BS, processing proceeds to step ST13 after the needle 32 has moved below the bed surface BS. In the sewing machine of this embodiment, the first stopper 68 of the stopper assembly 66 is used as a stopper for origin setting, and therefore, in step ST13, the feed pulse motor 62 is driven by steps of a number enough for the sector gear 60 to contact the first stopper 68, and thereby the feed dog 44 makes a retreat feeding motion of a process F1 to the first feed limit position PA as shown in FIG. 9(a). Then, in step ST14, the feed pulse motor 62 is excited into the predetermined phase a, and the feed dog 44 makes a forward feeding motion of a process F2, being positioned at the position P1 being the original position. In addition, the above-mentioned predetermined phase a is predetermined out of the phases a and b excited while the feed pulse motor 62 is moved by two steps from a specific position where the sector gear 60 contacts the first stopper 68.
After origin setting of the feed pulse motor 62 has been made, step ST15 is executed, and the flag FR is set, and thereafter the needle 32 ascends and the feed dog 44 protrudes above the bed surface BS. Then, in step ST16, the generation of timing signal TS is discriminated, and when generation of the timing signal TS is discriminated, step ST17 is executed and readout of data from the stitch pattern data memory 94 is performed. This data readout operation is performed by a system well known generally, and a second stitch pattern data on the selected stitch pattern is read by the address counter whose count accumulates in response to the timing signal TS. Also, a program is set in a manner that when the read data is a datum showing the end of the stitch pattern data of the selected stitch pattern, the head address of that stitch pattern is set again in the address counter. In step ST18, the needle swinging pulse motor 38 is driven according to the needle swing data in the read stitch pattern data, and the swing position of the needle 32 at the second stitch is determined. Subsequently, step ST19 is executed, and the feed pulse motor 62 is driven according to the feed data in the above-mentioned read stitch pattern data.
A feed control routine in step ST19 is programmed as shown in detail in FIGS. 8(a) and (b). This means that in step SBT1 as shown in FIG. 8(a), the feed pulse motor 62 is driven by steps of a number and direction (forward direction) in accordance with the feed data, and the feed dog 44 performs a forward feeding motion of a process F3. In step SBT2, the feed data is stored temporarily in the internal register R1, and in step SBT3, the level of the needle position signal UD is discriminated. When the needle 32 descends below the bed surface BS to form the second stitch and the feed dog 44 descends, in steps SBT4 and SBT5, the contents of the flags FN and HN are discriminated in sequence. At the present point, the flags FN and HN are reset, and accordingly step SBT6 is executed, and the feed pulse motor 62 is driven in the direction of retreat by steps of a number according to the feed data in the internal register R1, and the feed dog 44 performs a retreat feeding operation of a process F4, returning to the position P1. Then, as shown in FIG. 9(a), the four conventional feeding motions well known are performed, and in step ST20 as shown in FIG. 7(b), continuous operation of the sewing machine is performed until generation of the command signal MC commanding stop of the sewing machine and generation of the high-level needle position signal UD are discriminated simultaneously, and thereby a desired stitch pattern is formed.
Then, in step ST2, when the low level of the needle position signal UD is discriminated immediately after power to the sewing machine has been turned on, steps ST21, ST22 and ST23 shown in FIG. 7(c) are executed likewise the above-described steps ST13 through ST15 to perform origin setting of the feed pulse motor 62. Thereafter, the high level of the needle position signal UD is discriminated in step ST24, and when the needle 32 is positioned above the bed surface BS, processing proceeds to step ST3, and when positioned below the bed surface BS, the level of the command signal MC is discriminated in step ST25. In step ST25, when stop of the sewing machine is discriminated, processing returns to step ST24, and step ST24 is executed, and when start of the sewing machine is discriminated, the level of the needle position signal UD is discriminated in step ST26, and when the needle position signal UD changes to the high level, steps ST27 and ST28 for origin setting of the needle swinging pulse motor 38 are executed likewise the above-described steps ST3 and ST4. Thereafter, execution of steps ST16 through ST20 is repeated during the operation of the sewing machine, and stitch pattern forming is executed.
Subsequently, description is made hereinafter on the operation of the fabric feed device of this embodiment for eliminating step-out of the feed pulse motor 62 at start-up of the sewing machine and in continuous operation of the sewing machine.
Now, in the case as shown by a dash-colon line in FIG. 9(b), where the feed dog 44 is positioned at the position P4, protrudes from the bed surface BS and is stopped, and the feed pulse motor 62 is excited into and held at the phase d, if the sewing machine is started in this state, at the beginning the operator sometimes transfers forcedly the work fabric W in the forward direction to feed the work fabric W between the feed dog 44 and the presser foot 74, and the feed pulse motor 62 sometimes steps out into the next phase d in the forward direction due to this forced transfer. A forward feeding operation of a process F5 as shown in FIG. 9(b) is generated by the above-described out-of-step.
Description is made on operation of the stitch forming controlling apparatus 92 in the case where step-out is generated at start-up of the sewing machine. Start of the sewing machine is discriminated in step ST10, and subsequently the content of the flag FR is discriminated in step ST11, but when origin setting operation of the feed pulse motor 62 is executed once, the flag FR is set, and accordingly step ST29 is executed. When the needle position signal UD is high, the flag HN is set in step ST30, and when it is low, step ST30 is not executed, and processing moves to step SBT3 as shown in FIG. 8(a). When the low level of the needle position signal UD is discriminated in that step SBT3, the contents of the flags FN and HN are discriminated in steps SBT4 and STB5, but as described above, when the needle position signal UD is high immediately after the start of the sewing machine, the flag HN is set, and accordingly the flag HN is reset in step SBT7 shown in FIG. 8(b), step SBT8 is executed, the content of the internal register R1 and the next feed data are added, and the result thereof is stored temporarily in the internal register R1. Thereafter, step SBT9 is executed, and the content of the internal register R1 is subtracted from the maximum amount of feed of the feed dog 44, and the results thereof is stored temporarily in the internal register R2. In addition, in this embodiment, the maximum amount of feed of the feed dog 44 is equivalent to the amount of feed from the position P1 to the position P11.
The content of the internal register R2 is discriminated in step SBT10, and when the content is plus, step SBT11 is executed, and when it is minus, step SBT12 is executed, and thereafter processing proceeds to step SBT13, but when it is zero, processing proceeds directly to step SBT13. For example, when the content of the internal register R2 is "1", step SBT11 is executed and the feed pulse motor 62 is driven in the direction of forward feed by one step, and the feed dog 44 performs a forward feeding motion of a process F6. After the flag FN has been set in step SBT13, processing proceeds to step ST20 to perform discriminating operation, and when generation of the timing signal TS is discriminated in step ST16, the next stitch pattern data is read out in step ST17, positioning of the needle 32 is performed according to the needle swing data in that stitch pattern data in step ST18, and subsequently in step SBT1, the feed pulse motor 62 is driven according to the feed data in the stitch pattern data. This feed data is for executing a process MF1 of six-step forward feeding motion as shown by a dash-colon line in FIG. 9(b), and therefore the feed dog 44 performs a forward feeding motion of a process F7 from the position P9, and the sector gear 60 contacts the second stopper 70 whose position corresponds to the second feed limit position PB. In this embodiment, in the feed pulse motor 62, excitation change equivalent to six steps is performed and the final excitation phase is determined to be the phase c. This predetermined phase c is one phase out of the phases b and c into which the feed pulse motor 62 is excited while the sector gear 60 moves by two steps from the defining position where it contacts the second stopper 70. Accordingly, when the feed pulse motor 62 is excited into the predetermined phase c, the feed dog 44 performs a retreating horizontal feeding motion of a process F8, and thereby step-out of the feed pulse, motor 62 is eliminated. Thereafter, when the feed dog 44 descends, the low level of the needle position signal UD is discriminated in step SBT3, and the content of the flag FN is discriminated in step SBT4. When a motion equivalent to the horizontal feeding motion of the process MF1 is executed after start of the sewing machine, the flag FN is set, and accordingly setting of the flag FN is discriminated in step SBT4, and in step SBT14, the fed pulse motor 62 is driven in the direction of retreat by 10 steps equivalent to the maximum amount of feed, and the feed dog 44 performs a retreating horizontal feeding motion of a process F9 to the position P1. Thereafter, the flag FN is reset in step SBT15, and processing proceeds to step ST20.
Description is made on the case where the sewing machine is started and is put in continuous operation as described above, and thereafter an overload in the direction of retreat is applied to the feed dog 44 due to transfer of the thick part of the work fabric W or the like, and thereby the feed pulse motor 62 falls into step-out.
For example, in the case of continuous operation of the sewing machine, an overload is applied when a process MF2 of seven-step forward feeding motion as shown by a dash-colon line in FIG. 9(c) is executed, and the actual feeding motion is a motion of a process F10, in step SBT6 as shown in FIG. 8(a), the feed pulse motor 62 is driven in the direction of retreat by seven steps of the motion of the process MF2, and accordingly the feed dog 44 is made to retreat until the sector gear 60 contacts the first stopper 68 whose position corresponds to the first feed limit position PA, performing a horizontal feeding motion of a process F11. At the end of this process F11, the feed pulse motor 62 is excited into the predetermined phase a, and therefore the feed dog 44 performs a process F12, being positioned at the position P1. Thus, out-of-step of the pulse motor 62 in continuous operation of the sewing machine is eliminated.
In addition, in this embodiment, the operation according to steps SBT6 and SBT14 is equivalent to the operation of the first excitation controlling means, the operation according to step SBT1 is equivalent to the operation of the second excitation controlling means, and the operation according to steps ST29, ST30, SBT1, SBT3 through SBT6 and SBT14 and the like is equivalent to the operation of the movement sequence setting means.
The present invention is not to be limited to the embodiment as detailed above, and various changes and modifications may be made therein without departing from the spirit and scope of the present invention as claimed.
For example, in this embodiment, the stitch forming controlling apparatus 92 and the main motor controlling apparatus 88 are constituted separately, but these apparatuses may be constituted with a microcomputer.
Also, in this embodiment, the motion of the process F7 toward the second feed limit position PB is executed as a motion of forward feed of the work fabric W by the feed dog 44 after start of the sewing machine, but it is needless to say that the motion of the process F7 may be changed to the motion of the process H1 in the state that the feed dog descends as shown in FIG. 2.
Furthermore, in this embodiment, the start position of the horizontal feeding motion in continuous operation of the sewing machine is determined to be position P1, but the start position can be determined to be an arbitrary position, or the start position may differ in every horizontal feeding motion. Thus, in the case where the start position differs from the position P1, a change may be made in a manner that the operation of exciting the predetermined phase at start or end of the horizontal feeding motion is performed every several times of the horizontal feeding motions.
Further, as feeding means driven directly by the feed pulse motor, it is possible to arrange plural roller means driven directly by the feed pulse motor, instead of the feed dog.
|
In order to correct the asynchronous state of a feed pulse motor of a sewing machine used to reciprocate a feed for feeding a fabric to a sewing needle, a feed control apparatus is provided which switches the pulse motor to a predetermined excited state when the feed dog abuts a stopper on the downstream side of feed motion at the start up of sewing operation so as to locate the feed dog at a known reference position. Additionally, the feed control apparatus switches the pulse motor to another predetermined excited state when the feed dog abuts a stopper on the upstream side of the feed motion so as to locate the feed dog at a known position during consecutive sewing operation.
| 3
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a double glazing arrangement.
2. Description of the Prior Art
Sash windows incorporating counterbalance systems are well known.
It is also known to provide a double glazing arrangement without a counterbalance system in which two panes are mounted between two opposed, vertical double channels for sliding movement therein, and having releasable catches for holding the respective pane in a plurality of raised positions. However, before each pane can be removed, it is necessary to partially dismantle the arrangement.
SUMMARY OF THE INVENTION
According to the invention a double glazing arrangement includes at least one pane mounted between two opposed vertical channels and arranged for both vertical sliding movement within the confines of the channels without the provision of a counterbalance system and movement in at least one lateral direction for removal of the pane without any initial dismantling of the arrangement, and releasable catches for both holding the pane in a plurality of raised positions and preventing the lateral movement of the pane.
Preferably the pane is capable of movement in either lateral direction, the pane having one of the catches at or adjacent each corner, each catch protruding further into the respective channel than the pane for sliding engagement with a vertical guideway therein, and each catch being capable of being withdrawn to allow the pane to be removed. Each catch is preferably spring held relative to the associated guideway within the adjacent channel.
It is also preferred that the catch at or adjacent each bottom corner of the pane protrudes still further into the respective channel past the associated guideway, and each channel has a series of internal stops at different heights for releasable engagement by the free end of the adjacent bottom catch. Each bottom catch may be mounted for pivotal movement to release the end of the catch from the stop with which it is engaged.
The stops within each channel are preferably provided by transverse sleeves through which pass fixing screws for that channel. Alternatively the stops may be the fixing screws themselves.
The double glazing arrangement may have two panes, and releasable catches for each frame.
The or each pane may include a sheet of transparent acrylic material.
The channels preferably include the side lengths of an outer frame.
BRIEF DESCRIPTION OF THE DRAWINGS
Various other objects, features and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings, in which like reference characters designate like or corresponding parts through the several views and wherein:
FIG. 1 is a diagrammatic vertical section through a double glazing arrangement, the catches for both panes being omitted;
FIG. 2 is a diagrammatic horizontal section through part of the double glazing arrangement of FIG. 1, the catches again being omitted;
FIG. 3 is a perspective exploded view of one of the bottom catches of the double glazing arrangement of FIG. 1 for retaining the vertical sliding panes and for holding them in a raised position;
FIG. 4 is a similar exploded view to FIG. 3 of one of the top catches;
FIGS. 5 to 10 show three plan views and corresponding sections illustrating the operation of the bottom catches of FIG. 3; and
FIG. 11 is a plan view of a modified side length of the outer frame.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 to 10, a double glazing arrangement for two vertically sliding panes 10 has an outer frame 11 formed of four extruded lengths of unplasticised polyvinyl chloride or aluminium alloy. Each side length 12 (FIG. 2) has two channels 13 defining parallel slideways for vertical sliding movement of the panes 10. Access to the base of each channel 13 is restricted by longitudinal, spaced apart ribs 14 which provide an outwardly facing guideway within the channel and form an inner chamber 15 through which the side length 12 is attached to a window surround 16 by screws 17 at spaced intervals. Each screw 17 passes through a sleeve 18 within the inner chamber 15 of the respective channel and after fixing the side length in position the heads of the screws are concealed by individual screw head covers or a continuous cover strip. In this embodiment there is provided a continuous cover strip 19 which is a push fit into a longitudinal groove in the external face of the wall 20 of the side length remote from the window surround 16. The purpose of the sleeves 18 and guide ribs 14 is described below.
The bottom length 21 of the outer frame 11 is of L cross-section of which the base wall 22 provides for attaching the bottom length to the window sill by screws 23 and the back wall 24 provides a surface for engagement by a sealing brush 25 forming a part of the outer sliding pane 10.
The top length 26 of the outer frame primarily has a vertical flange 27 through which the top length is attached to the window surround 16 by screws 28, and a central, downwardly extending flange 29 which provides a surface for engagement by a sealing brush 30 forming a part of the inner sliding pane 10.
In this embodiment each sliding pane 10 includes a sheet 31 of transparent acrylic material surrounded by a frame again formed of four extruded lengths. The opposed top and bottom lengths 32 are of the same cross-section having an integral glazing gasket 33. In one wall of the glazing gasket 33 is a side facing groove capable of holding a sealing brush which is either one of the above mentioned brushes 25, 30 or a further brush 34. Each top and bottom length 32 also has an outwardly facing groove 35 which is partially closed by side ribs 36 defining a longitudinal slot 51.
The opposed side lengths 37 of the frame of each sliding pane again have the same cross-section as each other, each length including a glazing gasket having grooves on both sides for reception of sealing brushes 38.
Adjacent ends of the lengths 32, 37 are held in position by their functional engagement with the sheet 31, and are assembled so that the top and bottom lengths 32 overlap the side lengths 37. The outwardly facing grooves 35 of the top and bottom lengths are thus open at their ends.
As shown in FIG. 2, the side lengths 37 of the frame of each pane 10 are spaced from the guide ribs 14 of the respective channels 13 within which the pane slides. Each pane is thus able to be moved laterally to remove the pane from the outer frame 11.
However, during normal operation, each pane 10 is prevented from such lateral movement by two bottom catches 39 (FIG. 3) and two top catches 40 (FIG. 4) which are positioned one at each open end of the top and bottom lengths 32 and are held by springs 41 within the grooves 35 so that they protrude outwardly therefrom in a sliding engagement with the associated vertical guideway provided by the ribs 14 of the adjacent channel 13 (FIGS. 5 and 6). For this purpose, each spring 41 has two arms 42, 43 extending longitudinally of the respective groove 35, one arm 42 having an end 44 bent to engage in a socket 45 in the respective catch 39,40 and the other arm 43 having a profile 46 capable of locking onto the end of the respective length 32, to one side of the glazing gasket 33.
Each bottom catch 39 has a trigger portion 47 protruding downwardly through the slot 51 of the bottom length 32 and each top catch 40 has an upstanding knob 48 protruding through the slot 51 of the upper length 32 whereby the respective catch may be withdrawn longitudinally into its groove 35, the associated spring 41 distorting sideways, if it is required to remove the pane.
Each of the two bottom catches 39 also has a relatively narrow pointed end 49 which in the extended position of the catch (FIGS. 5 and 6) protrudes into the inner chamber 15 of the respective channel 13 to rest on the sleeve 18 through which passes one of the fixing screws 17. Each bottom catch 39 also has a tapered portion 50 adjacent its trigger 47 which allows the catch to be pivoted (FIG. 8) to release the end 49 from the sleeve 18.
In operation, each pane 10 is held at a raised position by engagement of the bottom catches 39 with the sleeves 18 through which pass the side fixing screws 17 of the outer frame 11 (FIGS. 5 and 6).
To raise or lower the pane 10 to a new height, the bottom catches 39 are pivoted out of engagement with the sleeves 18 (FIGS. 7 and 8).
For removal of the pane, the bottom catches 39 are pivoted out of engagement with the sleeves 18 and also all four catches 39, 40 are withdrawn inwardly of the grooves 35 (FIGS. 9 and 10), thereby allowing the pane to be moved laterally of the outer frame 11 and removed therefrom.
In the above described embodiment, each top catch 40 has the same form of spring 41 as each bottom catch 39. Alternatively the spring for each top catch 40 may be a simple coil spring extending longitudinally between the catch and a stop inwardly along the respective groove 35.
FIG. 11 shows a modified side length 12 of the outer frame 11 in which the cover strip 42 for the heads of the fixing screws forms a hinged, integral part of the extruded side length 12.
If desired, the sleeves 18 may be omitted. The fixing screws 17 then serve the stops engaged by the bottom catches 39.
Obviously, numerous modifications are 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 double glazing arrangement has at least one pane mounted between two opposed vertical channels and arranged for both vertical sliding movement within the confines of the channels without the provision of a counterbalancing system and movement in at least one lateral direction for removal of the pane without any initial dismantling of the arrangement. Releasable catches are provided which are for both holding the pane in a plurality of raised positions and preventing lateral movement of the pane. The arrangement is particularly advantageous for a pane of transparent acrylic material.
| 4
|
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This application claims the benefit of the filing date of U.S. Provisional Patent Application No. 60/955,919 filed on Aug. 15, 2007.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to educational course Content development, and more particularly to a computer based system and method for the creation and access of dynamic course content and associated media products.
2. Description of Related Art
Traditional courses that are taught in, for example, a college or university environment, often rely heavily on a textbook for course content. Over the years, many courses have been taught based on a chapter to chapter approach to learning. This approach has been proven to work well with static, and often times mature technical fields. With the continued growth in knowledge dissemination technologies driven by computers and networking, many fields of endeavor today change and evolve fairly quickly, leaving the static textbook model of course content development lacking current and timely information. In addition, textbooks are still largely bound and printed materials, which makes changes and updates difficult and costly. This disparity between, the need for current and timely information and the static confines of traditional textbooks has forced many textbook publishers to add supplemental materials to their textbook offerings. These supplemental materials may include videos, slides, supplements and addenda, course packs, ancillaries, and other such add-ons. The offering of supplemental materials by textbook publishers, while an improvement over the static nature of the textbook itself, is still, however, static. Although publishers have begun to provide a number of online resources in the form of online quizzes and interactive flash cards, for example, these are targeted at students and for the most part still remain fixed in nature, and do not adequately address the need for fresh, dynamic material in course content development.
The addition of dynamic and current material to ah otherwise static textbook approach to learning has been recognized by many innovative faculty members, professors, and course instructors. Not only does the addition of such dynamic and current material add to the overall learning experience, but the use of current, real world applications of theoretical course concepts also captures the interest and attention of students, making classroom time more effective and productive.
The task of locating, reviewing and using dynamic and current material in the development of course content has been relegated to those instructors who have the time, determination and energy to seek out relevant articles, news clippings, and other timely and current media information. Once appropriate content is found, it is often times out of date by the time a course is taught in subsequent quarters or semesters. This creates a burden on the instructor to continually seek out timely and relevant information for each upcoming class. The ongoing search for relevant and timely course content has in the past been very labor intensive, and as a result is often times not done with consistency and thoroughness.
It is therefore an object of the present invention to provide a system and method for the creation and access of dynamic course content. It is another object of the present invention to provide a system and method for the creation and access of dynamic course content that correlates the structure of a selected textbook with current content media information. It is another object of the present invention to provide a system and method for the creation and access of dynamic course content that correlates media products to current content. It is another object of the present invention to provide a system and method for the creation and access of dynamic course content that has a search function for finding media products based on user search criteria. It is yet another object of the present invention to provide a system and method for the creation and access of dynamic course content that can be accessed through a network. It is yet another object of the present invention to provide a system and method for the creation and access of dynamic course content that allows a user to download media products based on user defined search and selection criteria. It is another object of the present invention to provide a method for the creation of a dynamic course syllabus where current content is correlated to events in a course. These and other objects of the present invention will become evident to one skilled in the art after a review of this specification, claims, and the attached drawings.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a system and method for the creation and access of dynamic course content having a computer program for correlating textbook structure data and course concepts with media products, a user interface for interaction with the computer program, a database of textbook structure data and course concepts operatively coupled to said computer program, at least one dynamic content source used in the creation of said media products, and a search utility.
The foregoing paragraph has been provided by way of introduction, and is not intended to limit the scope of this invention as defined by this specification, claims, and the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described by reference to the following drawings, in which like numerals refer to like elements, and in which:
FIG. 1 is a diagram depicting a prior art approach to course content development;
FIG. 2 is a top level block diagram of course content development using the system of the present invention;
FIG. 3 is a functional block diagram depicting the various logical components of the present invention;
FIG. 4 is a top level data access diagram of the present invention;
FIG. 5 is a flowchart depicting a typical user session of the present invention;
FIG. 6 is a screenshot of one embodiment of the present invention showing a media search session by textbook structure;
FIG. 7 is a screenshot of one embodiment of the present invention showing a media search session by key term; and
FIG. 8 is a screenshot of one embodiment of the present invention showing a media view following a media search session.
FIG. 9 is a flowchart depicting the syllabus creation routine of the present invention.
FIGS. 10-17 are various exemplary screenshots of the present invention.
The present invention will be described in connection with a preferred embodiment; however, it will be understood that there is no intent to limit the invention to the embodiment described. On the contrary, the intent is to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by this specification, claims, and the attached drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent files or records, but otherwise reserves all copyrights whatsoever.
For a general understanding of the present invention, reference is made to the drawings. In the drawings, like reference numerals have been used throughout to designate identical elements.
FIG. 1 is a diagram 100 depicting a prior art approach to course content development. A basic understanding of a common prior art approach to course content development will aid in understanding the present invention and its various embodiments thereof. Referring to FIG. 1 , static material such as a textbook, as well as ancillaries, course packs, and other material, as shown in block 101 , is often times used by an instructor, professor, faculty member, teacher, or other individual, to prepare course content for an upcoming course, seminar, class, session, lecture, or the like. The use of a textbook as the basis for course content has, in years past, been the de facto standard for course content development. The addition of instructor added materials 105 provides up-to-date, timely, and custom course content to the static textbook baseline.
This need to supplement static materials continues to grow. As information exchange has become faster and more streamlined through progress in the communications arts (computers, television, video and audio sources, and the like), the textbook by itself for many disciplines has become mostly insufficient for course content development. Publishers of textbooks and others reacted by offering ancillary materials to supplement textbooks, course packs, and other material. This was all offered up to the individual preparing the course content 103 . The disadvantage to such an approach is that this supplemental material is still primarily static in nature, and still does not represent timely, current real-world information. In addition, keeping these ancillary materials up to date is itself a chore.
The instructor, professor, faculty member, teacher, or other individual preparing the course content was driven to seek out supplemental, timely real-world materials. These miscellaneous instructor-added materials 105 were added to the course content 103 in an attempt to keep course content fresh, current, and interesting, There were also those instructors who would abandon the static textbook model altogether, and instead prepare course content strictly from materials located, gathered, and prepared by the instructor. Of course, the prior art processes described by way of FIG. 1 were, and still are, inefficient, time consuming, and in need of a better system for course content development.
Turning now to FIG. 2 , a top level block diagram 200 of course content development using the system of the present invention is depicted. Static material 201 such as a textbook, ancillaries, course packs and other material is mapped to a computer program 207 . The mapping uses the data relationships contained in the static material, such as title, chapter, author, publisher, ISBN number, year of publication, key terms, and the like. Current content 205 , such as business news, web sources, podcasts, blogs, and user generated content, is also received by the computer program 207 . The current content 205 is used, in some embodiments of the present invention, to generate media products (not shown in FIG. 2 ). The current content 205 is dynamic, and is updated on a regular basis either through the computer program 207 , manually, or through an external mechanism. The mapping, of static material 201 with dynamic current content 205 by way of the computer program 207 produces the useful and tangible output of course content 203 . The course content 203 produced by way of the present invention is enriched over course content developed by prior art approaches such as those described in FIG. 1 . The present; invention further contains functional elements that are described by way of FIG. 3 .
In FIG. 3 , a functional block diagram 300 depicting the various logical components of the present invention is illustrated. The various logical components described are contained either in, or operatively coupled with, the application software 301 . A database or other data schema containing textbook structure 303 is used to map or otherwise correlate key terms, course concepts and information contained in a static textbook or textbooks with media products and current content. This mapping or correlation facilitates ease of course content development and maintains the existing textbook-based foundation of many courses. The textbook structure 303 contains information such as, for example, title, chapter, author, publisher, ISBN number, year of publication, and other identifiers. Operatively coupled to the application software 301 is, in some embodiments of the present invention, a database or other data schema containing key terms 323 . Key terms are words, phrases, course concepts, and other elements that, may be used in conjunction with a search to aid a user in locating relevant and timely information that is suitable for their purposes. Also operatively coupled to the application software 301 is, in some embodiments of the present invention, current content 319 such as business news, web sources, podcasts, blogs, and user generated content. The current content 319 may be resident within the system of the present invention, or, in some embodiments, may be located on a separate system or systems and connected by way of networking techniques that are known to those skilled in the art. In addition to current content 319 , in some embodiments of the present invention videos 321 may be operatively coupled to the application software 301 . The videos 321 may be resident within the system of the present invention, or, in some embodiments, may be located on a separate system or systems and connected by way of networking techniques that are known to those skilled in the art. A database or other data schema containing slides 305 and the structure of the slides is also operatively coupled to the application software 301 . The slides may be, for example, Microsoft PowerPoint™ formatted slides, Apple Keynote™ slides, and the like. The structure of the slides may include, for example, slide title, article title, publication source, date of publication, notes, publication author, digital image, and other identifiers. The slides 305 are compiled based on current content, and may include, for example, summaries of current content articles and news stories. The slides 305 are updated regularly, and are accessible through the application software 301 . The slides 305 are used to supplement static content in the preparation of course content, and are searchable by way of the slide, structure elements, key terms, relationship to textbook structure, and the like. A search utility 307 is also coupled to the application software 301 , and provides a user with a multitude of search options designed to efficiently locate and download relevant and timely dynamic course content. Such utility is of paramount importance in the preparation of course content where relevant and timely information adds value and interest to a class, course, seminar, and the like. Searches using the search utility 307 may look for key terms, textbook structure, key elements in the slides, current content, videos, and other media products. In addition, full text searching may be performed where all media is searched for a selected term or phrase. As part of the search utility 307 , users will be able to filter their search results in a number of ways, for example, by date, media type, major subject, and the like. A user may, in certain situations, desire to run or otherwise display the media through live classroom use 306 . This allows the user to directly use the media in a classroom setting without the need to download the media. An appropriate software player may be used depending on the nature of the media (video, audio, presentation slides, text, and the like). The application software 301 also, in some embodiments of the present invention, has network connectivity 313 by way of a network 315 and user access 317 . Such network connectivity may include, for example, the internet, a local area network, a private network, a virtual private network, an optical network, a radio communications network, and the like. The system of the present invention also has a user interface 311 to allow a user to interact with the various functions of the application software such as search, download, browse, and the like. FIGS. 6 , 7 , and 8 depict an example of several screens of the user interface of the present invention. Also coupled to the application software 301 is a download utility 309 that allows a user to transfer media products such as slides, video, audio and the like. Download of media and other data is optional, and often at the discretion of the user. The user, in some embodiments of the present invention, may preview and then select desired media products, place them in a temporary storage location such as a virtual shopping cart, and then check out with the selected items using the download utility 309 . Payment processing may include credit card, fixed monthly, quarterly or periodic fees, and the like. If the user does not wish to download media or information, but wishes to flag the media for future reference, a save/mark media function 310 can be used. The save/mark media function 310 allows a user to mark media using a checkbox, highlighting, or the like. In addition, in some embodiments of the present invention, the media can be saved in a temporary location such as a folder, an album, or the like. The user can also use the saved or marked media without downloading by running the media by way of a network connection.
Continuing to refer to FIG. 3 , the MySyllabi function 312 is a customization feature that allows users to map the textbook and chapters to specific weeks (e.g., week 1, week 2 . . . week 8). This allows the system to then “suggest” media for review or playback in specific weeks of the course. The syllabus is the organizing focus of all courses. As part of the syllabus, instructors include a weekly schedule of readings and assignments. So, for example, students might need to read chapters 1 and 2 in week 1, chapter 3 in week 2 and so on. This provides a great opportunity to suggest media to instructors based on their syllabus textbook reading assignments. MySyllabi is a customization option that allows instructors to map a textbook and specific chapters to weeks in the semester or quarter. From that, the system presearches new slides and video and suggests them to the instructor. Course Instructors will need to create a mapped textbook syllabus in New Syllabus Setup and perform the following:
Select textbook from dropdown list
Map specific chapters to specific weeks
Name syllabus
Date of syllabus (actual date, semester/quarter/year)
Copy syllabus (for next time they teach this course. Optional)
Assign specific slides/videos/media from suggested media to specific weeks (optional). This should include drag and drop capabilities.
A flowchart depicting the interaction of a user with the MySyllabi functionality can be referred to in FIG. 9 , a description of which is provided later in this specification.
By way of example, and not limitation, Use Cases for the Application Software (INCLASSMEDIA) 301 are as follows:
Description
What a user sees and is able to do
1
Login
This is the page the user comes to when they go to
www.inclassmedia.com. They can either:
Sign-in with a username and password which takes them
to the default/home page or
Register for the first time.
They will see some thumbnails with the option to see an
enlarged image.
They should also see a streaming video or animated explanation
of what inclassmedia allows them to do.
2
Default/Home
This is the page users come to once they've signed in.
Page
They see rows of thumbnail images in LIFO order
representing either slides or videos that they can preview
or mark for some further action.
They see several SEARCH options
Textbook/chapter search:
Key term/full text search:
They see several tabs at top of page:
Saved Media (or myMedia)
mySyllabus
3
Thumbnail Actions
Thumbnails represent slides, videos, or other media (e.g.,
podcasts). Users can
Mouseover the thumbnail to see the notes section of the
slide or the description of the streaming video or other
media.
Left click on the slide to see full slide or to launch a
player to preview the video or other media.
Add the media to user's saved media (myMedia); users
should be able to add by dragging the thumbnail to the
saved media tab or by clicking a plus or add button.
Add the media directly to a specific virtual presentation
(Week 1, Pricing, etc.)
Remove the media from user's saved media
Rate the media
4
SEARCH Actions
Users have several search options:
Textbook/chapter search: where they can select their
textbooks from a dropdown box and then select the
chapter to search.
Key term/full text search: this is a suggestible search
for terms that would appear in textbooks. Users can also
search for any other term (e.g., Starbucks, China).
Users should be able to filter results by
Date (e.g., last week, month, 6 months, year)
Media type: slide, video, podcast/mp3, etc.
Major subject (e.g, Marketing, Strategy, Global
Business, etc.)
5
Registration
There should be several registration options:
Simple registration:
First name
Last name
Email address
Password
School (database/lookup)
Instructor status
Fulltime
Adjunct
Customize Profile
Primary Subject Interest
Marketing
Strategy
Global Business
Introduction to Business
Organizational Behavior
MIS
Finance
Accounting
Other
Notification Options
Email alerts when new material is added to
INCLASSMEDIA (when and how often)
6
Sign-in
Sign-in requests username and password. Also optionally
authentication.
Schools whose libraries have subscribed to full text database
services check authentication before allowing click-thru to
content provider database via proxy server.
If on campus, instructor gets passed through automatically (for
example, check IP address of machine on campus or domain
name); if off-campus, users are asked to input college userid
and password.
7
Saved Media
Users will be given storage space on server to save selected
(myMedia)
media.
They will access this from tab on top of page or link on page.
Users will save media after browsing thumbnails, with option to
save them from thumbnail image or from full slide or streaming
video view.
Saved media space has organizing functionality offering several
views. Over time users can save many slides, videos, and other
media (or pointers to those).
These are presented to users as thumbnail views in LIFO order
similar to the default/home page view.
Users primarily will want to
Preview slides, videos, and other media to decide if they
should use them in class
Organize media into virtual presentations for classroom
playback/viewing. For example, selecting 3 or 4 slides
in a particular order to “play” in class
Name the virtual presentations (e.g., Week 2, Pricing,
etc.)
Remove them from saved media storage (i.e., un mark
them)
If they have many saved slides, they will want to search
through them using the same search options as they have
with the larger database of media.
8
mySyllabus
The syllabus is the organizing focus of all courses. As part of
the syllabus, instructors include a weekly schedule of readings
and assignments. So, for example, students might need to read
chapters 1 and 2 in week 1, chapter 3 in week 2 and so on. This
provides a great opportunity to suggest media to instructors
based on their syllabus textbook reading assignments.
mySyllabus is a customization option that allows instructors to
map a textbook and specific chapters to weeks in the semester
or quarter. From that, the system presearches new slides,
videos, and other media, and suggests them to the instructor.
Instructors will need to create a mapped textbook syllabus in:
New Syllabus Setup:
Select textbook from dropdown list
Map specific chapters to specific weeks
Name syllabus
Date of syllabus (actual date, semester/quarter/
year)
Copy syllabus (for next time they teach this
course)
Associate specific slides/videos/media from suggested
media to specific events such as virtual presentations,
specific weeks, etc.. This should include drag and drop
capabilities.
9
Admin
Admin comprises a number of activities:
a. Add Media/Edit Media
b. Add/Edit Topics
c. Add/Edit Key terms
d. Add/Edit Source Publications
e. Add/Edit Textbooks
f. Add/Edit Users
g. Add/Edit Schools
h. Reports/Analytics
9a
Add Media/Edit
Add media. Need to upload media to server and define it for the
Media
system. Media will have a number of fields that define it:
Title
Type
Source (journal/publication name)
Date (publication date)
Date entered into the system
Key terms
Topics (topics are a higher-level hierarchical level in the
database schema). All key terms when they get entered
in the system need to be associated with one or more
topics.
Illustrates. A field in the notes section of slides or added
as description with video and other media to tell the
instructor why this is relevant. Instructor can use this
verbatim in discussing the media in class.
Article Context: this is also part of the notes section of
the slides.
Link to full text article. This is what the library calls a
“persistent link” or a URL that gets passed through the
library's proxy server directly to the content provider's
database to pop the full text of the article in another
browser window.
Image (such as jpeg) for the thumbnail.
9b
Add/Edit Topics
Topics are high-level business concepts that include many key
terms. They tend to be equivalent in many cases to chapter
headings (e.g., Pricing, Distribution, Advertising, etc), their
primary purpose is to better manage thousands of key terms.
For example, when adding key terms to a particular slide, it is
easier to select key terms from a shorter more relevant list
associated with a topic (Pricing, for example, which might
include a list of 30 key terms), rather than from the entire list of
thousands of key terms.
Key terms are associated with at least one topic
9c
Add/Edit Key
When media get added to the database, they are assigned key
Terms
terms. These terms are searchable and correspond to terms of
the same name that are entered in the database when textbooks
are added. (Terms are added to chapters during the textbook
input process.)
This is a key concept in the ICM value proposition and allows
instructors to find very relevant media. It also allows the
system to suggest media in mySyllabus (above).
The easiest way to add new key terms is to have the system
recognize them when a slide is uploaded to the database. If the
key term already exists (i.e., it was added during textbook setup
or manually earlier), fine; if not, the system flags this as a new
key term and requires that the admin associate the term with a
topic and textbook chapter.
9d
Add/Edit Source
Each slide is derived so to speak from an article in the business
Publications
press ( Wall St. Journal , New York Times , The Economist , etc.).
When slide is created, admin needs to associate it with a source
publication.
Users might search for media based on this source.
Slide shows source attribution at bottom of every slide.
Admin also enters publication date.
9e
Add/Edit
Users have the option to search for media by selecting a
Textbooks
textbook and chapter from a drop down list.
Textbook creation or input includes:
Adding/Deleting Textbook Information
Textbook title
Textbook authors
Textbook publisher
Textbook edition
Adding/associating Chapters with textbooks
Chapter title
Chapter number
Assigning Key Words
Editing Chapters
Adding or deleting key words
Changing chapter titles or numbers (not likely
unless mistake)
9f
Add/Edit Users
Users will be automatically added during the registration
process.
Admin will need to add users or deny access, or review and
modify user information; i.e., admin access to user data.
Customer data will be available for reports and analysis
9g
Add/Edit Schools
Registration requires inputting of college/university. This is
best done through a drop down list.
Admin will enter or edit this list.
9h
Reports/Analytics
Number of users
Number of media
Media Usage
Most popular
Usage by media type
Usage by school
Usage by users
Usage by primary subject area
Usage by date (day, week, month)
Saved Media (myMedia)
Number of saved media accounts
Number of media saved
Number of mySyllabus accounts
Number of virtual presentations
Searches by
Textbook/Chapter
Key terms
Other full text terms
Most popular search terms
Turning now to FIG. 4 , a top level data access diagram 400 of the present invention is shown. The application software 301 delivers various media products 305 such as slides, videos, audio, and the like by mapping static textbook structures to current dynamic content. Current content used to create the media products includes, for example, business news 401 (with sources such as CNN, Business Week, The Economist, The Wall Street Journal, and the like), blogs 403 , web sources 405 , podcasts 407 , other categories 409 , and user generated content 411 . The application software 301 may also provide, in some embodiments of the present invention, access to current content directly or through an intermediary provider, system or network. The media products 305 are often based on current content, and may be created by individuals and placed on or within the application software 301 , or may be created by users themselves, or may further be created by way of software of a combination of software and individual or group efforts. The media products 305 may also, in some embodiments of the present invention, be procured from third parties or content providers. The application software is searchable using search 307 and network access 315 techniques. The search may look for key terms, textbook structure, key elements in the slides, current content, videos, and other media products. In addition, full text searching may be performed where all media is searched for a selected term. As part of the search utility 307 , users will be able to filter their search results in a number of ways, for example, by date, media type, major subject, and the like. Network access 315 may include, for example, the internet, a local area network, a private network, a virtual private network, an optical network, a radio communications network, and the like.
Turning now to FIG. 5 , a flowchart 500 can be seen that depicts a typical user session of the present invention. At the start of the session 501 , a user is prompted to search by textbook data in decision 503 . If the user does not desire to search by textbook data, they may in step 511 perform a full text search, search by keyword, browse most recent media, or select other search criteria. Once their search is completed in step 511 , they will receive a listing of relevant media in step 509 , have the ability to optionally sort the media by date range, media type, major subject, key term, etc. in step 513 . In step 515 , they will view the desired media in the application, and in step 517 , the user will save or mark the desired media, or optionally download the media in step 518 . If no media is saved, marked or downloaded in steps 517 or 518 , the user can run another search in step 521 . Similarly, once the desired media is saved, marked or downloaded in steps 517 or 518 , the user can also run another search in step 521 . If, in decision 503 , the user desires to search by textbook data, they may select the textbook title in step 505 , select the textbook chapter in step 507 , and receive a listing of relevant media in step 509 . The user also has the ability to optionally sort the media by date range, key term, etc. in step 513 . In step 515 , they will view the desired media in the application, and in steps 517 or 518 , the user will save, mark or download the desired media. If no media is saved, marked or downloaded in steps 517 or 518 , the user can run another search in decision step 521 . Similarly, once the desired media is saved, marked or downloaded in steps 517 or 518 , the user can also run another search in step 521 . To terminate the process, if another search is, not elected in decision step 521 , the session is ended in step 523 . The steps described by way of FIG. 5 are by example, and not limitation. Other similar and additional steps may be known to those skilled in the art, and are not intended to be a departure from the fundamental attributes of the present invention as defined herein.
Turning now to FIGS. 6 , 7 , and 8 , several screen shots of one embodiment of the present invention are depicted.
FIG. 6 shows a media search session by textbook structure. As can be seen, a textbook title is selected from a drop down list, and the chapters of the selected textbook also appear in a drop down list. The user may search for media products such as slides that are mapped to the selected title and chapter of the textbook selected. A preview of each of the media products is then displayed, as can be seen in FIG. 6 , and the user can select the desired media products for retention and subsequent download. As seen in FIG. 6 , a search may also include date range and or key terms.
FIG. 7 further depicts a media search session with a drop down list of key terms displayed.
FIG. 8 depicts a media view following a media search session. A close up of the selected media, in this example slides, is shown along with a notes field at the bottom of the slide.
Referring now to FIG. 9 , a flowchart depicting the syllabus creation routine of the present invention is shown. As previously described by way of FIG. 3 , the MySyllabi functionality allows users to map their selected textbook and chapters to specific weeks of the course, with the application then returning suggested media for review or playback in specific weeks of the course.
When a user selects the MySyllabi functionality, they can either view syllabi that currently exists in step 903 , view suggested media in step 905 that is provided by the application, or elect to create a dynamic syllabus in step 907 . If they elect to create a syllabus in step 907 , the user can optionally assign syllabus name(s) 909 . The application then collects course information in step 911 such as the course number, course name, and start date. The user then selects the textbook they plan to use in step 913 , and then the user maps textbook chapters to specific weeks in step 915 , and saves the syllabus they have created in step 917 . In step 919 , media relevant to the course are returned to the user, and the user previews the media in step 921 and creates associations between the media and the syllabus, as well as other variables such as week, event, presentation, and the like. In step 923 , if the user elects to create another syllabus, they are returned to step 907 . Should they not elect to create another syllabus, the routine is ended and they may return home in step 925 .
Lastly, to provide a complete understanding of the present invention and the various embodiments described herein, FIGS. 10-17 are various exemplary screenshots of the present invention. These, exemplary screenshots are not intended to be limiting in any way, but rather, are intended to provide examples of one embodiment of the present invention that, when taken with this specification and the remaining drawings, will provide one skilled in the art with an adequate understanding of the present invention such the present invention and its various embodiments can be made and used.
It is, therefore, apparent that there has been provided, in accordance with the various objects of the present invention, a computer based system and method for the creation and access of dynamic course content and associated media products.
While the various objects of this invention have been described in conjunction with preferred embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of this specification, claims, and the attached drawings.
|
The creation of course content for college and university courses, seminars, lectures, and other pedagogical activities has in the past relied heavily on a textbook. Using a textbook for course content creation creates a static, rigid course framework that fails to consider timely, relevant real world information that is dynamic and changing. This results in courses that are stagnant and hot well rounded. The present invention, and the various embodiments thereof, describes a computer based system and method for the creation and access of dynamic course content and associated media products. The present invention utilizes dynamic current content sources such as news, web sources, blogs, podcasts, user generated content, and other sources to create media products such as slides, videos, audio and the like. The media products of the present invention are keyed to the static framework of a textbook or textbooks, and are searchable, by textbook structure media structure, key terms, date range, and the like.
| 6
|
FIELD OF THE INVENTION
[0001] The present invention belongs to the field of pharmaceutical chemistry, particularly, relates to the methods for preparing brexpiprazole, the analogs, key intermediates, and salts thereof, also relates to novel compounds provided during the preparation.
BACKGROUND OF THE INVENTION
[0002] Brexpiprazole (Brexpiprazole, Code: OPC-34712) is a new generation of anti-psychotic drug candidates developed by Otsuka Pharmaceutical Co., Ltd., it takes effect on several receptors, i.e., it is the dopamine D2 receptor partial agonist (improving positive and negative symptoms, cognitive disorder and depressive symptoms), 5-HT2A receptor antagonist (improving negative symptoms, cognitive function disorder, symptoms of depression, insomnia), al adrenergic receptor antagonists (improving the positive symptoms of schizophrenia), 5-hydroxytryptamine uptake/reuptake inhibitors (improving depressive symptoms), a 5-HT1A partial agonist (having anxiolytic and antidepressant activity) and 5-HT7 antagonists (adjusting body temperature, circadian rhythm, learning and memory, sleep) at the same time. Currently, a Phase III clinical trial for adjuvant treatment of severe depression (MIDD) is conducted in the United States and Europe; a Phase III clinical trial for the treatment of schizophrenia is conducted in the United States, Europe and Japan; meanwhile, a Phase II clinical trial for Adult ADHD (attention deficit hyperactivity disorder) is conducted in the United States.
[0003] A preparation route of brexpiprazole is disclosed in the PCT application WO2006112464 A1 by Otsuka Pharmaceutical Co., Ltd. as shown in Scheme 1, the disadvantage of this route is that by-products that cannot be easily separated are produced in the first step of the reaction, intermediates with high purity cannot be easily obtained even by column chromatography. Thus it suffered from reduced purity and yield of the final product brexpiprazole.
[0000]
[0004] Then, another preparation route of this reaction is disclosed in the PCT application WO2013015456 A1 by Otsuka Pharmaceutical Co., Ltd. as shown in Scheme 2, the reagents used in the route are relatively expensive, so the disadvantage of the route is costly, environmental-ly unfriendly and not suitable for industrial production.
[0000]
[0005] There are disadvantages of highcost, formation of impurities hard to separate for the above preparation method. Thus it is necessary to find a new route which is economic, practical and environmentally friendly, so as to improve process stability, reduce the cost and improve the product quality.
SUMMARY OF THE INVENTION
[0006] In response to these disadvantages, it is an object of the present invention to provide a new method for preparing brexpiprazole, the analogs, key intermediates and salts thereof with simple operation, high yield, low cost, environmentally friendly and suitable for industrial mass production.
[0007] It is another object of the present invention to provide novel compounds and salts thereof during the preparation.
[0008] In order to achieve the above object, the present invention provides compounds of formula I as shown in the following structure:
[0000]
[0009] wherein, R is linear or branched C1 to C6 alkyl, benzyl, preferably, R is linear or branched C1 to C4 alkyl group, most preferably, R is methyl, ethyl or t-butyl;
[0010] R1 is
[0000]
[0000] acyl-based amino-protecting groups (e.g. formyl
[0000]
[0000] acetyl, propionyl, benzoyl, haloacetyl, phthaloyl), or alkoxycarbonyl-based amino-protecting groups (e.g. t-butoxycarbonyl, benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl); the haloacetyl group is fluoroacetyl, bromoacetyl, chloroacetyl or iodoacetyl; preferably, R 1 is selected from
[0000]
[0000] formyl, acetyl and t-butoxycarbonyl;
[0011] The present invention further provides a method for preparing a compound as shown in formula I, where the compound of formula II is reacted with a thioglycollic acid ester compound, obtaining the compound of the formula I, as shown in Scheme 3,
[0000]
[0012] wherein, X is halogen, such as fluorine, chlorine, bromine, iodine; the definition of R and R 1 are the same as that in the above compound of the formula I;
[0013] The above reaction is conducted in the presence of a base, in particular, it is conducted in the presence of an inorganic base (e.g. sodium hydroxide, potassium hydroxide, strontium hydroxide, lithium hydroxide, barium hydroxide, calcium hydroxide, cesium hydroxide, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, strontium carbonate, cesium carbonate, sodium sulfide, sodium hydride, etc.) or an organic base (e.g., sodium alkoxide, potassium alkoxide, butyl lithium, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), pyridine, quinoline, 4-dimethylaminopyridine (DMAP) or an organic amine, etc.), wherein, said sodium alkoxide may be sodium methoxide, sodium ethoxide, sodium propoxide, sodium isopropoxide, sodium n-butoxide, sodium tert-butoxide and the like; said potassium alkoxide may be potassium methoxide, potassium ethoxide, potassium propoxide, potassium isopropoxide, potassium n-butoxide, potassium tert-butoxide and the like, the organic amine may be triethylamine, diethylamine, tri-n-butylamine, tripropylamine, diisopropylamine, diisopropylethylamine, etc., preferably, the base may be an inorganic bases, such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, strontium carbonate, sodium sulfide, sodium hydride, or organic bases, such as sodium methoxide, sodium ethoxide, potassium t-butoxide, triethylamine, diethylamine, diisopropylamine or diisopropylethylamine;
[0014] The above reaction is conducted in a suitable solvent, the solvent is one or more selected from the group consisting of water, C1-C5 lower alcohol (such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-pentanol, isopentanol, ethylene glycol, propylene glycol, glycerol), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane, N-methylpyrrolidone, dichloromethane, chloroform, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether or ethylene glycol monomethyl ether, and the like, preferably, the solvent is one or more selected from the group consisting of water, methanol, ethanol, N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane or ethylene glycol dimethyl ether; the reaction time is 1 hour to 24 hours, preferably 2 hours to 12 hours. The reaction temperature is 0° C. to 150° C., preferably from room temperature to 100° C.
[0015] In order to achieve the above object, the present invention further provides compounds of formula III as shown in the following structure:
[0000]
[0016] wherein, R 1 1 is
[0000]
[0000] acyl-based amino-protecting groups (e.g. formyl, acetyl, propionyl, benzoyl, haloacetyl, phthaloyl), or alkoxycarbonyl-based amino-protecting groups (e.g. t-butoxycarbonyl, benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl); the haloacetyl group is fluoroacetyl, bromoacetyl, chloroacetyl or iodoacetyl;
[0017] preferably, R 1 is
[0000]
[0000] formyl, acetyl or t-butoxycarbonyl;
[0018] The present invention further provides a method for preparing a compound as shown in formula III, where the compound of formula II is reacted with thioglycollic acid obtaining the compound of the formula III, as shown in Scheme 4,
[0000]
[0019] wherein, X is fluorine, chlorine, bromine or iodine; the definition of R 1 is the same as that in the above compound of the formula I;
[0020] The above reaction is conducted in the presence of a base, in particular, it is conducted in the presence of an inorganic base (e.g. sodium hydroxide, potassium hydroxide, strontium hydroxide, lithium hydroxide, barium hydroxide, calcium hydroxide, cesium hydroxide, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, strontium carbonate, cesium carbonate, sodium sulfide, sodium hydride, etc.) or an organic base (e.g., sodium alkoxide, potassium alkoxide, butyl lithium, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), pyridine, quinoline, 4-dimethylaminopyridine (DMAP) or an organic amine, etc.), wherein, said sodium alkoxide may be sodium methoxide, sodium ethoxide, sodium propoxide, sodium isopropoxide, sodium n-butoxide, sodium tert-butoxide and the like; said potassium alkoxide may be potassium methoxide, potassium ethoxide, potassium propoxide, potassium isopropoxide, potassium n-butoxide, potassium tert-butoxide and the like, the organic amine may be triethylamine, diethylamine, tri-n-butylamine, tripropylamine, diisopropylamine, diisopropylethylamine, etc., preferably, the base may be an inorganic bases, such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, strontium carbonate, sodium sulfide, sodium hydride, or organic bases, such as sodium methoxide, sodium ethoxide, potassium t-butoxide, triethylamine, diethylamine, diisopropylamine or diisopropylethylamine;
[0021] The above reaction is conducted in a suitable solvent, the solvent is one or more selected from the group consisting of water, C1-C5 lower alcohol (such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-pentanol, isopentanol, ethylene glycol, propylene glycol, glycerol), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane, N-methylpyrrolidone, dichloromethane, chloroform, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether or ethylene glycol monomethyl ether, and the like, preferably, the solvent is one or more selected from the group consisting of water, methanol, ethanol, N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane or ethylene glycol dimethyl ether; the reaction time is 1 hour to 24 hours, preferably 2 hours to 12 hours. The reaction temperature is 0° C. to 150° C., preferably from room temperature to 100° C.
[0022] The present invention further relates to the following compounds:
[0023] Compound of formula IV:
[0000]
[0024] wherein, R 1 is acyl-based amino-protecting groups (e.g. formyl, acetyl, propionyl, benzoyl, haloacetyl, phthaloyl), or alkoxycarbonyl-based amino-protecting groups, e.g. benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl; the haloacetyl group is fluoroacetyl, bromoacetyl, chloroacetyl or iodoacetyl; preferably, R 1 is formyl or acetyl group;
[0025] and a compound of formula V and salts thereof:
[0000]
[0026] wherein the salt is one selected from the group consisting of hydrochloride, sulfate, phosphate, nitrate, acetate, hydrobromide, hydroiodide, perchlorate, trichloroacetate and trifluoroacetate.
[0027] The present invention further provides a method for preparing a compound of formula IV, said method comprises the step to obtain the compound of formula III by the hydrolysis reaction of the compound of formula I or by the Scheme 4 from the compound of formula II, followed by the decarboxylation step to give a compound of formula IV, said method is shown in Scheme 5:
[0000]
[0028] wherein, X is fluorine, chlorine, bromine or iodine; the definition of R 1 and R are the same as that in the above compound of the formula I; The present invention also provides a method for preparing key intermediates of Brexpiprazole or the salts thereof, the method is shown in Scheme 6:
[0000]
[0029] wherein, R 1 is acyl-based amino-protecting groups (e.g. formyl, acetyl, propionyl, benzoyl, haloacetyl, phthaloyl), or alkoxycarbonyl-based amino-protecting groups (e.g. tert-butoxycarbonyl, benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl); the haloacetyl group is fluoroacetyl, bromoacetyl, chloroacetyl or iodoacetyl; preferably, R 1 is a formyl, acetyl group or tert-butoxycarbonyl; X is fluorine, chlorine, bromine or iodine;
[0030] R is linear or branched C1 to C6 alkyl, benzyl, preferably, R is linear or branched C1 to C4 alkyl group, more preferably, R is methyl, ethyl or t-butyl;
[0031] Specifically, the invention includes the following steps:
[0032] preparing the compound of formula III by the hydrolysis reaction of the compound of formula I, or by the Scheme 4 from the compound of formula II, then producing a compound of formula IV by decarboxylating of formula III, finally, preparing the key intermediate of Brexpiprazole (compound as shown in formula VI) or the salts thereof by removing the amino-protecting groups:
[0033] or preparing the compound of formula V or the salts thereof firstly by removing the amino-protecting groups from the compound of formula III, then preparing the compound of formula VI or the salts thereof by decarboxylating;
[0034] or preparing the compound of formula VI or the salts thereof by simultaneously conducting decarboxylation and removal of the amino-protecting groups from the compound of formula III;
[0035] or preparing the compound of formula V or the salts thereof by simultaneously conducting hydrolysis and removal the amino-protecting groups under the acidic conditions from the compound of formula I, then preparing the compound of formula VI or the salts thereof by decarboxylating;
[0036] wherein, the salts of the compounds of formulae V and VI are one selected from the group consisting of hydrochloride, sulfate, phosphate, nitrate, acetate, hydrobromide, hydroiodide, perchlorate, trichloroacetate and trifluoroacetate, the above-described salts can be alkalized to obtain the compound of formulae V and VI as required.
[0037] In scheme 5 or scheme 6, the hydrolysis reaction may be conducted under acidic conditions, said acid may be organic acids or inorganic acids, such as one or more selected from sulfuric acid, hydrochloric acid, gaseous hydrogen chloride, hydrobromic acid, hydroiodic acid, phosphoric acid, nitric acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, perchloric acid and the like, but is not limited to the above-mentioned acids; the hydrolysis reaction may also be conducted in the presence of a base, in particular, it is conducted in the presence of an inorganic base (e.g. sodium hydroxide, potassium hydroxide, strontium hydroxide, lithium hydroxide, barium hydroxide, calcium hydroxide, cesium hydroxide, sodium bicarbonate, potassium bicarbonate, potassium carbonate, sodium carbonate, strontium carbonate, cesium carbonate, sodium hydride, etc.) or an organic base (e.g., sodium alkoxide, potassium alkoxide, butyl lithium, potassium acetate, sodium acetate, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), pyridine, quinoline, 4-dimethylaminopyridine (DMAP) or an organic amine, etc.), wherein, said sodium alkoxide may be sodium methoxide, sodium ethoxide, sodium propoxide, sodium isopropoxide, sodium n-butoxide, sodium tert-butoxide and the like; said potassium alkoxide may be potassium methoxide, potassium ethoxide, potassium propoxide, potassium isopropoxide, potassium n-butoxide, potassium tert-butoxide and the like, the organic amine may be triethylamine, diethylamine, tri-n-butylamine, tripropylamine, diisopropylamine, diisopropylethylamine, etc., preferably, the base is an inorganic bases, such as sodium hydroxide, potassium hydroxide or lithium hydroxide; The hydrolysis reaction is conducted in a suitable solvent, the solvent is one or more selected from the group consisting of water, C 1 to C 5 lower alcohol (such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-pentanol, isopentanol, ethylene glycol, propylene glycol, glycerol), N,N-dimethylformamide (DMF), N,N-dimethylacetamide, dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane, morpholine, N-methylpyrrolidone, dichloromethane, chloroform, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether or ethylene glycol monomethyl ether, and the like, preferably, the solvent is one or more selected from the group consisting of water, methanol, ethanol, tetrahydrofuran (THF), dioxane; the reaction temperature is 0° C. to 200° C., preferably 100° C.; the reaction time is 10 minutes to 24 hours, preferably 0.5 hours to 10 hours;
[0038] The decarboxylation reaction may be conducted with or without the presence of a catalyst, said catalyst is selected from copper, copper chromite, cuprous oxide, cupric oxide, chromium trioxide, cuprous bromide, cuprous chloride, ferrous chloride, ferric chloride, cupric carbonate, cupric sulfate, basic cupric carbonate, silver acetate, calcium oxide, calcium hydroxide, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), aluminum oxide, preferably is one or more selected from copper, copper chromite, cuprous oxide, cupric oxide, chromium trioxide, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) or aluminum oxide; or the decarboxylation is conducted in the presence of silver carbonate and acetic acid; the solvent for decarboxylation reaction may be one or more selected from the group consisting of quinoline, isoquinoline, N-methylpyrrolidone (NMP), quinoxaline, ethylene glycol dimethyl ether, diphenyl ether, biphenyl, ethylene glycol, diethylene glycol, diethylene glycol dimethyl ether, dibutyl ether, toluene, xylene, mesitylene, hexanol, heptanol, N,N-dimethyl formamide, dimethyl sulfoxide, dioxane, N,N-dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, pyridine, preferably one or more from quinoline, quinoxaline, ethylene glycol dimethyl ether, N,N-dimethylformamide, dimethylsulfoxide, dioxane or the N,N-dimethylacetamide; and the reaction temperature is from room temperature to 300° C., preferably 120-250° C.; the reaction time is 5 minutes to 18 hours.
[0039] The removal of amino-protecting group is conducted in the presence of an acid, wherein the acid is selected from the group consisting of hydrochloric acid, gaseous hydrogen chloride, sulfuric acid, phosphoric acid, nitric acid, acetic acid, hydrobromic acid, hydriodic acid, perchloric acid, trichloroacetic acid or trifluoroacetic acid; The reaction solvent is one or more selected from water, dioxane, methanol, ethanol, n-propanol, isopropanol, tert-butanol, diethyl ether, N-methylpyrrolidone, tetrahydrofuran, acetonitrile, methylene chloride, chloroform, N,N-dimethylformamide, ethyl acetate, propyl acetate or butyl acetate, or the above acid may be used as a reaction solvent, without adding other solvent; the reaction temperature is 0° C. to 150° C., preferably the reaction temperature is 100° C.; the reaction time is 0.5 to 24 hours, preferably 1 to 12 hours;
[0040] The one-step method which simultaneously conduct the decarboxylation and removal of amino-protecting group is conducted in the presence of an acid, wherein the acid is one or more selected from the group consisting of hydrochloric acid, gaseous hydrogen chloride, sulfuric acid, phosphoric acid, nitric acid, acetic acid, hydrobromic acid, hydriodic acid, perchloric acid, trichloroacetic acid or trifluoroacetic acid; the reaction solvent is one or more selected from water, dioxane, methanol, ethanol, n-propanol, isopropanol, tert-butanol, diethyl ether, N-methylpyrrolidone, tetrahydrofuran, acetonitrile, methylene chloride, chloroform, N,N-dimethylformamide, ethyl acetate, propyl acetate or butyl acetate, or the above acid may be used as a reaction solvent, without adding other solvent; the reaction temperature is 0° C. to 150° C., preferably from room temperature to 100° C.; the reaction time is 0.5 to 24 hours, preferably 1 to 12 hours; alternatively, when R 1 is alkoxycarbonyl-based amino-protecting groups (e.g. tert-butoxycarbonyl, benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl), the one-step method which simultaneously conduct the decarboxylation and removal of amino-protecting group may be conducted with or without the presence of a catalyst, said catalyst is one or more selected from copper, copper chromite, cuprous oxide, cupric oxide, chromium trioxide, cuprous bromide, cuprous chloride, ferrous chloride, ferric chloride, cupric carbonate, cupric sulfate, basic cupric carbonate, silver acetate, calcium oxide, calcium hydroxide, 1,8-diazabicyclo [5,4,0] undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), aluminum oxide, preferably is one or more selected from copper, copper chromite, cuprous oxide, cupric oxide, chromium trioxide, 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) or aluminum oxide; or the reaction is conducted in the presence of silver carbonate and acetic acid; the reaction solvent may be one or more selected from the group consisting of quinoline, isoquinoline, N-methylpyrrolidone (NMP), quinoxaline, ethylene glycol dimethyl ether, diphenyl ether, biphenyl, ethylene glycol, diethylene glycol, diethylene glycol dimethyl ether, dibutyl ether, toluene, xylene, mesitylene, hexanol, heptanol, N,N-dimethyl formamide, dimethyl sulfoxide, dioxane, N,N-dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, pyridine; preferably one or more from quinoline, quinoxaline, ethylene glycol dimethyl ether, N,N-dimethylformamide, dimethylsulfoxide, dioxane or the N,N-dimethylacetamide; and the reaction temperature is from room temperature to 300° C., preferably 120-250° C.; the reaction time is 5 minutes to 18 hours.
[0041] In the step of simultaneously conducting the hydrolysis reaction and removal of amino-protecting group under acidic conditions, said acid may be organic acids or inorganic acids, such as one or more selected from sulfuric acid, hydrochloric acid, gaseous hydrogen chloride, hydrobromic acid, hydroiodic acid, phosphoric acid, nitric acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, perchloric acid and the like, but is not limited to the above-mentioned acids; the reaction solvent is one or more selected from the group consisting of water, C 1 to C 5 lower alcohol (such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, tert-butanol, n-pentanol, isopentanol, ethylene glycol, propylene glycol, glycerol), N,N-dimethylformamide (DMF), N,N-dimethylacetamide, dimethyl sulfoxide (DMSO), tetrahydrofuran (THF), acetonitrile, dioxane, morpholine, N-methylpyrrolidone, ethyl acetate, dichloromethane, and the like, or the above acid may be used as a reaction solvent, without adding other solvent; the reaction temperature is 0° C. to 200° C., preferably from room temperature to 100° C.; the reaction time is 0.5 to 24 hours, preferably 1 hours to 12 hours.
Technical Effect
[0042] The present invention has the following advantages:
[0043] When R 1 is selected from acyl-based amino-protecting groups (e.g. formyl
[0000]
[0000] acetyl, propionyl, benzoyl, haloacetyl, phthaloyl), or alkoxycarbonyl-based amino-protecting groups (e.g. tert-butoxycarbonyl, benzyloxycarbonyl, 9-fluorenyl methoxycarbonyl), especially when R 1 is preferably formyl, acetyl, or tert-butoxycarbonyl, the cost of the reagent is low, and the reaction conditions for removing these protecting groups is mild, e.g., under acidic conditions, so as to directly obtain the stable salt form of the compound of formula V and VI type, which avoids the further salifying step of unstable freebase, thus reducing one reaction step. And the whole process for removing the amino-protecting group does not need expensive reagents and special reaction equipment. U.S. Pat. No. 5,436,246 discloses the case in which R 1 is benzyl, but the debenzylation reaction conditions is harsh, which require expensive palladium reagents and special reaction kettle, thus it is costly and relatively dangerous.
[0044] By contrast, the method for the present invention is easy to operate, the used reagents are cheap and easy-to-get, thus it save the synthesis cost, shorten the production cycle, improve the yield and product quality, and is suitable for mass production.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] The present invention is further illustrated by the following specific examples. It should be understood, the following examples are only used for illustration of the present invention without intended to limit the scope of the invention.
[0046] The present invention is further illustrated by following examples but without any limitation.
Reference Example 1
Synthesis of tert-butyl 4-(3-chloro-2-formylphenyl)piperazine-1-carboxylate
[0047]
[0048] 2-chloro-6-fluorobenzaldehyde (500 mg, 3.15 mmol), tert-butyl piperazine-1-carboxylate (646 mg, 3.47 mmol) and potassium carbonate (2.18 g, 15.77 mmol) were added to N,N-dimethylformamide (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 80° C. for 4 hours, cooled and filtered. Water (20 mL) was added thereto, then the mixture was extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate, filtered to remove the drying agent, and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to obtain a pale yellow solid (750 mg, yield 75%).
[0049] 1 HNMR (400 MHz, CDCl 3 ): δ 10.37 (s, 1H), 7.40 (t, 1H), 7.01 (d, 1H), 6.99 (d, 1H), 3.20 (m, 4H), 3.00 (s, 4H), 1.47 (s, 9H). ESI: [M+1] + =325.8.
Reference Example 2
Synthesis of 4-(3-chloro-2-formylphenyl)piperazine-1-carbaldehyde
[0050]
[0051] 2-chloro-6-fluorobenzaldehyde (500 mg, 3.15 mmol), 1-formyl piperazine (396 mg, 3.47 mmol) and potassium carbonate (2.18 g, 15.77 mmol) were added to DMF (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 80° C. for 4 hours, cooled, added with water (20 mL) and extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to give a pale yellow solid (588 mg, yield 70%).
[0052] 1 HNMR (400 MHz, CDCl 3 ): δ 10.45 (s, 1H), 8.13 (s, 1H), 7.44 (t, 1H), 7.18 (d, 1H), 7.02 (d, 1H), 3.80 (s, 2H), 36.4 (s, 2H), 3.10 (m, 4H). ESI: [M+1] + =253.1.
Reference Example 3
Synthesis of 2-(4-acetylpiperazin-1-yl)-6-chlorobenzaldehyde
[0053]
[0054] 2-chloro-6-fluorobenzaldehyde (500 mg, 3.15 mmol), 1-acetyl piperazine (444 mg, 3.47 mmol) and potassium carbonate (2.18 g, 15.77 mmol) were added to DMF (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 80° C. for 4 hours, cooled and filtered. Water (20 mL) was added thereto, then the mixture was extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to obtain a pale yellow solid (588 mg, yield 70%).
[0055] 1 HNMR (400 MHz, CDCl 3 ): δ 10.44 (s, 1H), 7.44 (t, 1H), 7.17 (d, 1H), 7.03 (d, 1H), 3.79 (bs, 4H), 3.10 (m, 4H), 2.18 (s, 3H). ESI: [M+1] + =267.1.
Example 1
Synthesis of tert-butyl 4-(2-(ethoxycarbonyl)benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0056]
[0057] The product of Reference Example 1 (1.0 g, 3.08 mmol), ethyl mercaptoacetate (388 mg, 3.20 mmol) and potassium carbonate (1.38 g, 10 mmol) were added to N,N-dimethylformamide (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 80° C. for 4 hours, cooled and filtered. Water (20 mL) was added thereto, then the mixture was extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to obtain a pale yellow solid (900 mg, yield 75%).
[0058] 1 HNMR (400 MHz, CDCl 3 ): δ 8.40 (s, 1H), 7.58 (d, 1H), 7.37 (t, 1H), 6.95 (d, 1H), 4.44 (q, 2H), 3.64 (m, 4H), 3.15 (m, 4H). ESI: [M+1] + =391.1.
Example 2
Synthesis of 4-(4-(tert-butoxycarbonyl)piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0059]
[0060] The product of Example 1 (1.0 g, 2.5 mmol) was dissolved into 1,4-dioxane (5 mL), then 4N sodium hydroxide aqueous solution (1.8 mL, 7.2 mmol) was added thereto. The mixture was stirred at 80° C. for 3 h, cooled to room temperature. Water (5 mL) and ethyl acetate (10 mL) were added and the aqueous phase was separated. The pH of the aqueous phase was adjusted with 1N HCl to about 4.0 at 0° C. The precipitated solid was filtered, dried to obtain a pale yellow solid.
[0061] 1 HNMR (400 MHz, DMSO-d 6 ): δ 7.98 (s, 1H), 7.64 (d, 1H), 7.42 (t, 1H), 6.95 (d, 1H), 3.53 (bs, 4H), 3.035 (bs, 4H). ESI: [M−1] − =361.1.
Example 3
Synthesis of tert-butyl 4-(benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0062]
[0063] The product of Example 2 (20 g, 54 mmol), cuprous oxide (1 g, 7 mmol) were dissolved in quinoline (50 mL) and the mixture was stirred at 140° C. overnight. After cooling and filtering, the filtrate was added with water, and extracted with ethyl acetate. The organic phase was washed with 1N HCl to be weakly acidic, washed with saturated sodium bicarbonate aqueous solution, then subjected to silica gel column chromatography. The concentrated solid was slurried in petroleum ether to give an off-white solid (13 g, 70% yield).
[0064] 1 HNMR (400 MHz, CDCl 3 ): δ 7.57 (d, 1H), 7.41 (s, 2H), 7.27 (t, 1H), 6.88 (d, 1H), 3.66 (m, 4H), 3.01 (m, 4H), 1.50 (s, 9H). ESI: [M+1] + =319.1.
Example 4
Synthesis of tert-butyl 4-(benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0065]
[0066] The product of Example 2 (500 mg, 1.35 mmol), silver carbonate (40 mg, 0.135 mmol) and acetic acid (8 mg) were dissolved in dimethyl sulfoxide (5 mL). The mixture was heated to 120° C. and stirred overnight, cooled and filtered. The filtrate was added with water, extracted with ethyl acetate. The organic layer was concentrated and subjected to column chromatography to give the target product.
[0067] 1 HNMR (400 MHz, CDCl 3 ): δ 7.57 (d, 1H), 7.41 (s, 2H), 7.27 (t, 1H), 6.88 (d, 1H), 3.66 (m, 4H), 3.01 (m, 4H), 1.50 (s, 9H). ESI: [M+1] + =319.1.
Example 5
Synthesis of 1-(benzo[b]thiophen-4-yl)piperazine hydrochloride
[0068]
[0069] The product of Example 3 (2 g, 6.2 mmol) was dissolved in dioxane (6 mL) and 4N HCl/dioxane solution (6 mL) was added. The mixture was stirred at room temperature for 3 h, and concentrated to dryness. The residue was slurried in ethyl acetate, filtered to obtain the target compound (1.3 g, yield 95%).
[0070] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 7.75 (d, 1H), 7.69 (d, 1H), 7.53 (t, 1H), 7.31 (t, 1H), 6.97 (t, 1H), 3.30 (bs, 8H). ESI: [M+1] + =219.2.
Example 6
Synthesis of ethyl 4-(4-formylpiperazin-1-yl)benzo[b]thiophene-2-carboxylate
[0071]
[0072] The product of Reference Example 2 (1.0 g, 3.7 mmol), ethyl mercaptoacetate (410 mg, 3.80 mmol), potassium carbonate (1.38 g, 10 mmol) were added to DMF (5 mL) under a nitrogen atmosphere at room temperature, the mixture was stirred at 80° C. for 4 hours, cooled and added with water (20 mL), extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to give a pale yellow solid (1.0 g, yield 83%).
[0073] 1 HNMR (400 MHz, CDCl3): δ 8.15 (d, 2H), 7.59 (d, 1H), 7.41 (t, 1H), 6.94 (d, 1H), 4.44 (q, 2H), 3.85 (t, 2H), 3.68 (t, 2H), 3.21-3.15 (m, 4H), 1.44 (t, 3H). ESI: [M+1] + =319.1.
Example 7
Synthesis of 4-(4-formylpiperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0074]
[0075] The product of Example 6 (1.0 g, 3.1 mmol) was dissolved in methanol (5 mL) and water (2 mL) and lithium hydroxide (420 mg, 10 mmol) was added. The mixture was stirred at room temperature for 5 h, added with water (5 mL) and extracted with ethyl acetate (10 mL). The aqueous phase was collected, the pH value was adjusted to about 4.0 with 1N HCl aqueous solution at 0° C. The precipitated solid was filtered and dried to give a pale yellow solid (510 mg, yield 56%).
[0076] ESI: [M−1] − =289.1.
Example 8
Synthesis of 4-(benzo[b]thiophen-4-yl)piperazine-1-carbaldehyde
[0077]
[0078] The product of Example 7 (1.0 g, 3.4 mmol), cuprous oxide (50 mg) were dissolved in quinoline (5 mL), and the mixture was stirred at 140° C. overnight. After cooling and filtering, the filtrate was added with water, and extracted with ethyl acetate. The organic phase was washed with 1N HCl aqueous solution to be weakly acidic, washed with saturated sodium bicarbonate aqueous solution, concentrated and then subjected to silica gel column chromatography. The obtained solid was slurried in petroleum ether to give an off-white solid (520 mg, 62% yield).
[0079] 1 HNMR (400 MHz, CDCl 3 ): δ 8.15 (s, 1H), 7.62 (d, 1H), 7.42 (m, 2H), 7.31 (t, 1H), 6.04 (d, 1H), 3.82 (t, 2H), 3.63 (t, 2H), 3.19-3.12 (m, 4H). ESI: [M+1] + =247.1.
Example 9
Synthesis of 1-(benzo[b]thiophen-4-yl)piperazine hydrochloride
[0080]
[0081] The product of Example 8 (500 mg) was dissolved in dioxane (2 mL) and 4N HCl/dioxane solution (3 mL) was added. The mixture was stirred at room temperature for 3 h, and concentrated to dryness. The residue was slurried in ethyl acetate, filtered to obtain the target compound (470 mg, yield 90%).
[0082] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 7.75 (d, 1H), 7.69 (d, 1H), 7.53 (t, 1H), 7.31 (t, 1H), 6.97 (t, 1H), 3.30 (bs, 8H). ESI: [M+1] + =219.2.
Example 10
Synthesis of ethyl 4-(4-acetylpiperazin-1-yl)benzo[b]thiophene-2-carboxylate
[0083]
[0084] The product of Reference Example 3 (1.0 g, 3.74 mmol), ethyl mercaptoacetate (388 mg, 3.20 mmol), potassium carbonate (1.38 g, 10 mmol) were added to DMF (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 80° C. for 4 hours, cooled and added with water (20 mL), extracted with ethyl acetate (3×5 mL). The organic layer was dried over anhydrous sodium sulfate and concentrated. The resulting solid was slurried in petroleum ether (50 mL) for 1 h, filtered to give a pale yellow solid (863 mg, yield 70%).
[0085] 1 HNMR (400 MHz, CDCl 3 ): δ 8.17 (s, 1H), 7.60 (d, 1H), 7.42 (t, 1H), 7.01 (d, 1H), 4.44 (q, 2H), 3.94 (br, 2H), 3.80 (br, 2H), 3.21 (br, 4H), 2.19 (s, 3H), 1.44 (t, 3H).
[0086] ESI: [M+1] + =333.3.
Example 11
Synthesis of 4-(4-acetylpiperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0087]
[0088] The product of Example 10 (1.0 g, 3.0 mmol) was dissolved in methanol (5 mL) and water (2 mL), and lithium hydroxide (300 mg, 7.2 mmol) was added. The mixture was stirred at room temperature for 3 h, water (5 mL) and ethyl acetate (10 mL) were added, and the aqueous phase was separated. The pH value of the aqueous phase was adjusted to about 4.0 with 1N HCl aqueous solution at 0° C. The precipitated solid was filtered and dried to give a pale yellow solid (820 mg, yield 90%).
[0089] ESI: [M−1] − =303.1.
Example 12
Synthesis of 1-(4-(benzo[b]thiophen-4-yl)piperazin-1-yl)ethanone
[0090]
[0091] The product of Example 11 (1.0 g, 3.2 mmol), cuprous oxide (50 mg) were dissolved in quinoline (5 mL), and the mixture was stirred at 140° C. overnight. After cooling and filtering, the filtrate was added with water, and extracted with ethyl acetate. The organic phase was washed with 1N HCl aqueous solution to be weakly acidic, washed with saturated sodium bicarbonate aqueous solution, concentrated and then subjected to silica gel column chromatography. The obtained solid was slurried in petroleum ether to give an off-white solid (600 mg, 70% yield).
[0092] 1 HNMR (400 MHz, DMSO-d 6 ): δ 7.95 (s, 1H), 7.65 (d, 1H), 7.41 (t, 1H) 6.95 (d, 1H), 3.69 (q, 4H), 3.10 (t, 2H), 3.02 (t, 2H), 2.06 (s, 3H). ESI: [M+1] + =261.1.
Example 13
Synthesis of 1-(benzo[b]thiophen-4-yl)piperazine hydrochloride
[0093]
[0094] The product of Example 12 (1 g) was dissolved in dioxane (6 mL), and 4N HCl/dioxane solution (6 mL) was added. The mixture was stirred at room temperature for 3 h and concentrated to dryness. The residue was slurried in ethyl acetate, filtered to obtain the product (870 mg, yield 90%).
[0095] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 7.75 (d, 1H), 7.69 (d, 1H), 7.53 (t, 1H), 7.31 (t, 1H), 6.97 (t, 1H), 3.30 (bs, 8H). ESI: [M+1] + =219.2.
Example 14
Synthesis of 1-(benzo[b]thiophen-4-yl)piperazine
[0096]
[0097] The product of Example 2 (500 mg, 1.38 mmol) was dissolved in quinoline (3 mL) and cuprous oxide (20 mg) was added. The mixture was stirred at 140° C. for 2 h and at 240° C. for 3 h, then cooled to room temperature, then filtered, added with water, extracted with ethyl acetate. The organic layer was washed with saturated sodium bicarbonate aqueous solution, and subjected to silica gel column chromatography, and concentrated to give the target product. 1 HNMR (300 MHz, DMSO-d 6 ): δ 8.74 (bs, 1H), 7.75 (d, 1H), 7.69 (d, 1H), 7.51 (d, 1H), 7.31 (t, 1H), 6.95 (d, 1H), 3.24 (m, 8H). ESI: [M+1] + =219.2.
Example 15
Synthesis of 4-(4-(4-((2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carb oxylic acid
[0098]
[0099] Ethyl 4-(4-(4-((2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carb oxylate (300 mg, 0.59 mmol) was dissolved in methanol (3 mL) and water (1 mL) and lithium hydroxide (76 mg, 1.8 mmol) was added. The mixture was stirred at room temperature for 3 h, extracted with ethyl acetate and the aqueous phase was separated. After the pH value was adjusted to 4.0 with 1N hydrochloric acid, the aqueous phase was extracted with dichloromethane and methanol (10:1), the organic layer was concentrated to dryness to obtain a white solid (210 mg, 46% yield).
[0100] 1 HNMR (400 MHz, DMSO-d 6 ): δ 10.01 (s, 1H), 7.88 (s, 1H), 7.61 (d, 1H), 7.38 (t, 1H), 7.03 (q, 1H), 6.93 (d, 1H), 6.48 (m, 2H), 3.92 (m, 4H), 3.35 (s, 4H), 2.84 (s, 4H), 2.77 (s, 2H), 2.62 (s, 2H), 1.72 (m, 4H), ESI: [M−1] − =478.3.
Example 16
Synthesis of 7-(4-(4-(benzo[b]thiophen-4-yl)piperazin-1-yl)butoxy)-3,4-dihydroquinolin-2(1H)-one
[0101]
[0102] The product of Example 15 (500 mg, 1.04 mmol), cuprous oxide (50 mg) were dissolved in quinoline (5 mL), and the mixture was stirred at 140° C. overnight. After cooling and filtering, water was added thereto, the mixture was extracted with ethyl acetate and the aqueous phase was separated. After the pH value was adjusted to 4.0 with 1N hydrochloric acid, the aqueous phase was extracted with dichloromethane and methanol (10:1), the organic layer was dried over anhydrous sodium sulfate, and subjected to silica gel column chromatography to give a solid (320 mg, yield 70%).
[0103] 1 HNMR (400 MHz, DMSO-d 6 ): δ 10.00 (s, 1H), 7.69 (d, 1H), 7.61 (d, 1H), 7.40 (d, 1H), 7.27 (t, 1H), 7.04 (d, 1H), 6.89 (d, 1H), 6.50 (dd, 1H), 6.45 (d, 1H), 3.93 (t, 2H), 3.06 (br, 4H), 2.78 (t, 2H), 2.60 (br, 4H), 2.41 (t, 4H), 1.74 (t, 2H), 1.60 (t, 2H). ESI: [M+1] + =436.3.
Example 17
Preparation of tert-butyl 4-(2-(ethoxycarbonyl)benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0104]
[0105] The product of Reference Example 1 (200 mg, 0.62 mmol), ethyl mercaptoacetate (0.081 ml, 0.74 mmol), potassium carbonate (342 mg, 2.48 mmol) were added to ethanol (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 85° C. for 18 hours, concentrated, and subjected to column chromatography to obtain the target product (100 mg, yield 42%).
[0106] 1 HNMR (400 MHz, CDCl 3 ): δ 8.40 (s, 1H), 7.58 (d, 1H), 7.37 (t, 1H), 6.95 (d, 1H), 4.44 (q, 2H), 3.64 (m, 4H), 3.15 (m, 4H). ESI: [M+1] + =391.1.
Example 18
Preparation of tert-butyl 4-(2-(ethoxycarbonyl)benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0107]
[0108] The product of Reference Example 1 (200 mg, 0.62 mmol), ethyl mercaptoacetate (0.081 ml, 0.74 mmol) and DIPEA (342 mg, 2.48 mmol) were added to DMF (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 105° C. for 18 hours, then 1N HCl aqueous solution was added to adjust the pH=7. The mixture was extracted with methyl t-butyl ether, the ether layer was washed with saturated saline for three times, dried over anhydrous sodium sulfate, filtered to remove the drying agent, concentrated, and subjected to column chromatography to obtain the target product (170 mg, yield 71%).
[0109] 1 HNMR (400 MHz, CDCl 3 ): δ 8.40 (s, 1H), 7.58 (d, 1H), 7.37 (t, 1H), 6.95 (d, 1H), 4.44 (q, 2H), 3.64 (m, 4H), 3.15 (m, 4H). ESI: [M+1] + =391.1.
Example 19
Preparation of tert-butyl 4-(2-(ethoxycarbonyl)benzo[b]thiophen-4-yl)piperazine-1-carboxylate
[0110]
[0111] The product of Reference Example 1 (200 mg, 0.62 mmol), ethyl mercaptoacetate (0.081 ml, 0.74 mmol) and sodium hydroxide (100 mg, 2.48 mmol) were added to ethanol (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 85° C. for 6 hours, concentrated and subjected to column chromatography to obtain the target product (70 mg, yield 30%). 1 HNMR (400 MHz, CDCl 3 ): δ 8.40 (s, 1H), 7.58 (d, 1H), 7.37 (t, 1H), 6.95 (d, 1H), 4.44 (q, 2H), 3.64 (m, 4H), 3.15 (m, 4H). ESI: [M+1] + =391.1.
Example 20
Preparation of 4-(piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid hydrochloride
[0112]
[0113] The product of Example 2 (200 mg, 0.55 mmol) was dissolved in THF (5 mL) and concentrated hydrochloric acid (0.5 mL) was added. The mixture was stirred at 50° C. for 6 h, cooled, added with methyl t-butyl ether (5 mL), filtered to give the target product (130 mg, 79% yield).
[0114] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 8.04 (s, 1H), 7.69 (d, 1H), 7.43 (t, 1H), 7.00 (d, 1H), 3.30 (bs, 8H). ESI: [M+1] + =262.9.
Example 21
Preparation of 1-(benzo[b]thiophen-4-yl)piperazine hydrochloride
[0115]
[0116] The product of Example 20 (130 mg, 0.43 mmol) was added to diphenyl ether (3 mL) and the mixture was stirred at 260° C. for 0.5 h. The mixture was cooled and filtered to give the target product (60 mg, 55% yield).
[0117] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 7.75 (d, 1H), 7.69 (d, 1H), 7.53 (t, 1H), 7.31 (t, 1H), 6.97 (t, 1H), 3.30 (bs, 8H). ESI: [M+1] + =219.2.
Example 22
Preparation of 4-(4-(tert-butoxycarbonyl)piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0118]
[0119] The product of Reference Example 1 (200 g, 0.62 mmol), mercaptoacetic acid (114 mg, 1.23 mmol) and sodium methoxide (133 mg, 2.45 mmol) were added to N,N-dimethylformamide (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 105° C. for 18 hours, cooled, added with water, extracted with ethyl acetate and separated. The pH of the aqueous phase was adjusted to around 5, the precipitated solid was filtered and dried to obtain the target product (130 mg, yield 58%).
[0120] 1 HNMR (400 MHz, DMSO-d 6 ): δ 7.98 (s, 1H), 7.64 (d, 1H), 7.42 (t, 1H), 6.95 (d, 1H), 3.53 (bs, 4H), 3.035 (bs, 4H). ESI: [M−1] − =361.1.
Example 23
Preparation of 4-(4-(tert-butoxycarbonyl)piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0121]
[0122] The product of Reference Example 1 (200 g, 0.62 mmol), mercaptoacetic acid (114 mg, 1.23 mmol) and sodium hydroxide (99 mg, 2.45 mmol) were added to N,N-dimethylformamide (5 mL) under a nitrogen atmosphere at room temperature. The mixture was stirred at 105° C. for 18 hours, cooled, added with water, extracted with ethyl acetate and separated. The pH of the aqueous phase was adjusted to around 5, the precipitated solid was filtered and dried to obtain the target product (180 mg, yield 81%).
[0123] 1 HNMR (400 MHz, DMSO-d 6 ): δ 7.98 (s, 1H), 7.64 (d, 1H), 7.42 (t, 1H), 6.95 (d, 1H), 3.53 (bs, 4H), 3.035 (bs, 4H). ESI: [M−1] − =361.1.
Example 24
Preparation of ethyl 4-(4-(4-((2-oxo-1,2-dihydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carboxylate
[0124]
[0125] 2-chloro-6-(4-(4-((2-oxo-1,2-dihydro-quinolin-7-yl)oxy)butyl)piperazin-1-yl) benzaldehyde (80 mg, 0.18 mmol) was dissolved in DMF (5 mL) and DIPEA (94 mg, 0.73 mmol) and ethyl mercaptoacetate (0.024 mL, 0.22 mmol) were added. The mixture was stirred at 110° C. for 16 hours, cooled, added with water, extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous sodium sulfate, and subjected to silica gel column chromatography to give a solid (40 mg, 46% yield).
[0126] 1 HNMR (400 MHz, DMSO-d 6 ): δ 11.69 (s, 1H), 11.24 (s, 1H), 8.09 (s, 1H), 7.81 (d, 1H), 7.74 (d, 1H), 7.57 (d, 1H), 7.48 (t, 1H), 7.04 (d, 1H), 6.82 (m, 2H), 6.30 (d, 1H), 4.32 (m, 4H), 4.06 (t, 2H), 3.67-3.16 (m, 8H), 1.96 (m, 2H), 1.84 (m, 2H), 1.32 (t, 3H). ESI: [M+1] + =506.4.
Example 25
Synthesis of 4-(4-(4-((2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carb oxylic acid
[0127]
[0128] Ethyl 4-(4-(4-((2-oxo-1,2,3,4-tetrahydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carb oxylate (100 mg, 0.19 mmol) was dissolved in acetic acid (3 mL) and concentrated hydrochloric acid (0.5 mL) and the mixture was stirred at 100° C. for 10 hours. The reaction mixture was poured into ice water, stirred for 10 min followed by filtration to obtain the target product (40 mg, 43% yield).
[0129] 1 HNMR (400 MHz, DMSO-d 6 ): δ 10.01 (s, 1H), 7.88 (s, 1H), 7.61 (d, 1H), 7.38 (t, 1H), 7.03 (q, 1H), 6.93 (d, 1H), 6.48 (m, 2H), 3.92 (m, 4H), 3.35 (s, 4H), 2.84 (s, 4H), 2.77 (s, 2H), 2.62 (s, 2H), 1.72 (m, 4H), ESI: [M−1] − =478.3.
Example 26
Preparation of 7-(4-(4-(benzo[b]thiophen-4-yl)piperazin-1-yl)butoxy)-3,4-dihydroquinolin-2(1H)-one
[0130]
[0131] The product of Example 25 (400 mg, 0.83 mmol) and silver carbonate (46 mg, 0.16 mmol) were dissolved in DMSO (5 mL) and acetic acid. The mixture was stirred at 120° C. overnight, cooled, added with water, extracted with ethyl acetate. The ethyl acetate layer was washed with saturated sodium bicarbonate and brine each for once, dried over anhydrous sodium sulfate, and subjected to silica gel column chromatography to give a solid (80 mg, 22% yield).
[0132] 1 HNMR (400 MHz, DMSO-d 6 ): δ 10.00 (s, 1H), 7.69 (d, 1H), 7.61 (d, 1H), 7.40 (d, 1H), 7.27 (t, 1H), 7.04 (d, 1H), 6.89 (d, 1H), 6.50 (dd, 1H), 6.45 (d, 1H), 3.93 (t, 2H), 3.06 (br, 4H), 2.78 (t, 2H), 2.60 (br, 4H), 2.41 (t, 4H), 1.74 (t, 2H), 1.60 (t, 2H). ESI: [M+1] + =436.3.
Example 27
Preparation of 74-(4-(4-((2-oxo-1,2-dihydroquinolin-7-yl)oxy)butyl)piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid
[0133]
[0134] 2-chloro-6-(4-(4-((2-oxo-1,2-dihydro-quinolin-7-yl)oxy)butyl)piperazin-1-yl) benzaldehyde (80 mg, 0.18 mmol) was dissolved in DMF (5 mL) and sodium hydroxide (29 mg, 0.73 mmol) and mercaptoacetic acid (0.025 mL, 0.36 mmol) were added. The mixture was stirred at 120° C. for 16 hours, cooled, added with water. The pH value of the aqueous phase was adjusted to around 5 with 11\T HCl aqueous solution. The mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous sodium sulfate and subjected to silica gel column chromatography to give a solid (40 mg, 46% yield).
[0135] ESI: [M+1] + =478.0.
Example 28
Preparation of 4-(piperazin-1-yl)benzo[b]thiophene-2-carboxylic acid hydrochloride
[0136]
[0137] The product (100 mg, 0.25 mmol) of Example 17 was dissolved in acetic acid (3 mL) and concentrated hydrochloric acid (0.5 mL) and the mixture was stirred at 100° C. for 10 hours. The reaction mixture was poured into ice water, stirred for 10 min followed by filtration to obtain the target product (38 mg, 50% yield).
[0138] 1 HNMR (400 MHz, DMSO-d 6 ): δ 9.46 (bs, 2H), 8.04 (s, 1H), 7.69 (d, 1H), 7.43 (t, 1H), 7.00 (d, 1H), 3.30 (bs, 8H). ESI: [M+1] + =262.9.
|
The present invention relates to the methods for preparing brexpiprazole, the analogs, key intermediates, and salts thereof, specifically, the present invention relates to a new method for preparing brexpiprazole, the analogs, key intermediates, and salts thereof, and the key intermediates, and salts thereof provided during the preparation. The preparation method has a mild reaction condition, stable intermediate, easy operation, and uses cheap and easy-to-get reagents, thus it saves the synthesis cost, shortens the production cycle, improves the yield and product quality, and is suitable for mass production.
| 2
|
This application is a continuation of U.S. patent application Ser. No. 10/452,343 filed Jun. 2, 2003 now U.S. Pat. No. 6,828,552, which is a divisional of U.S. patent application Ser. No. 10/180,813 entitled “Field Ionizing Elements and Applications Thereof” filed Jun. 25, 2002, now U.S. Pat. No. 6,642,526, which claims benefit of U.S. Provisional Application No. 60/301,092, filed Jun. 25, 2001, U.S. Provisional Application No. 60/336,841 filed on Oct. 31, 2001, and U.S. Provisional Application No. 60/347,685 filed on Jan. 8, 2002, all of which are hereby fully incorporated by reference.
This invention was made in part with Government support under contract NASA-1407 awarded by NASA. The Government has certain rights in this invention.
BACKGROUND
Many different applications are possible for ionization systems. For example, it is desirable to form a pumpless, low mass sampling system for a mass spectrometer.
Conventional mass spectrometers often use “hard” techniques of producing ion fragments, in which certain parts of the molecule are forcibly removed, to form the fragmented ion. For example, the fragments may be produced by ultraviolet, radioactive, and/or thermal electron ionization techniques. Some of these techniques, and specifically the thermal technique, may require a vacuum to enhance the life of the filament source.
Different systems which use ionization are known. A quadrupole and magnetic sector/time of flight system ionizes a sample to determine its content. These devices have limitations in both operation and size. Many devices of this type may operate over only a relatively small mass sampling range. These devices may also suffer from efficiency issues, that is the ions might not be efficiently formed.
Many of these systems also require a very high vacuum to avoid ion collisions during passage through the instrument. For example, the systems may require a vacuum of the level of such as 10 −6 Torr. A vacuum pump must be provided to maintain this vacuum. The vacuum pump consumes power, may be heavy, and also requires a relatively leak free environment. This clashes with the usual desire to miniaturize the size of such a device.
Other applications could be desirable for ionization, if an ionization system were sufficiently small. However, the existing ionization systems have problems and difficulties in fabrication which has prevented them from being used in certain applications.
SUMMARY
The present application describes a special ionization membrane, along with applications of this special ionization membrane that are facilitated by the membrane.
A first application uses the ionization membrane as part of a mass spectrometer.
Another application uses the ionization membrane for other applications. According to an aspect of this invention, the electrodes are formed closer than the mean free path of a specified gas, for example the gas being considered. This may ionize gas molecules in free space. Different applications of this soft ionization technique are described including using this system in a mass spectrometer system, such as a rotating field mass spectrometer. This may also be used in a time of flight system.
In an embodiment, a pumpless mass spectrometer is described which does not include a pump for either forming the vacuum or for driving the ions.
Another embodiment describes using this system for an electrochemical system. Another application describes using this system in propulsion.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects will now be described in detail with reference to the accompanying drawings, wherein
FIG. 1 shows Paschen curves for various gases;
FIGS. 2 a – 2 c show details of the special ionization membrane of the present system, with FIG. 2 b showing a cross-section along the line 2 b — 2 b in FIG. 2 c and FIG. 2 a showing a close-up detail of one of the holes in FIG. 2 b;
FIG. 3 shows an ion mobility spectrometer;
FIG. 4 shows a solid-state ionization membrane being used in an electrochemical device;
FIG. 5 shows the ionization membrane being used as a propulsion system;
FIG. 6 shows this propulsion system in its housing with top and bottom accelerator grids; and
FIG. 7 shows an aperture to carry the gas into the ionization field.
DETAILED DESCRIPTION
Gas may be ionized in a high electric field. Avalanche arcing may be produced by the gas ionization. It has been found by the present inventor, however, that when the “mean free path” between molecules is greater than electrode separation, only ionization occurs.
FIG. 1 shows the Paschen curves for various gases. This represents the breakdown voltage of the gas at various characteristic points. On the left side and under each Paschen curves ionization of the gas occurs using the special membrane described herein. This technique is “soft” in the sense that it ionizes without fragmenting the molecular structure of the gas being ionized. That means that large organic compounds can be analyzed without breaking them into smaller atomic fragments.
Details of the membrane are shown in FIGS. 2A–2C , with FIGS. 2A & 2B showing cross sections of the membrane of FIG. 2C . The miniature ionization device 99 is formed by micromachining an array of small holes 100 through a relatively thin membrane 105 . The membrane 105 may be, for example, of sub micron thickness. The material 106 of the substrate itself may be silicon or any other easy-to-machine material. Metal electrodes 120 , 122 are located on respective sides of the membrane 100 . The metal can be any material such as chrome or titanium or gold.
In formation of the membrane 99 , a plurality of holes such as 130 are formed from the bottom 132 . The holes may generally taper as shown towards the top portion 133 of the hole. The top portion 133 of the hole 130 may have a dimension 137 which may be, for example, 2 to 3 microns. Openings may be formed in the top metal coating 120 , and in the bottom metal coating 122 . For example, the hole may be formed by focused ion-beam milling (maskless process).
The substrate material 106 also includes a dielectric layer 134 which can be for example, silicon nitride, alumina, or any other similar material that has a similar dielectric breakdown. The thickness 136 of the dielectric layer sets the distance between the metal electrodes 120 and 122 . The dielectric thickness can be to 200–300 nm The dielectric can in fact be thinner than 200 nm, in fact can be any thickness, with thicknesses of 50 nm being possible.
In a preferred system, the distance between the electrodes 120 , 122 is less than 1 micron. When this small separation is maintained, electric field strengths on the range of mega volts per meter are produced for each volt of potential difference between the electrodes 120 , 122 .
The inventor has noted that the membranes could not be formed simply from the thin, sub micron elements. Membranes that are formed in this way could be too fragile to sustain a pressure difference across the membrane, or to survive a minor mechanical shock. In this embodiment, the thicker supporting substrate part 105 is used, and is back-etched through to the membrane. By forming the substrate in this way, that is with a relatively thick substrate portions such as 105 / 106 , separated by back etched holes such as 100 , the structure of the device can be maintained while keeping a relatively small distance between the electrodes.
An embodiment is described herein which uses the field ionizer array, which may be a micromachined field ionizer membrane, with a lateral accelerator, which is coupled to a mass spectrometer. An array of cathodes may be deployed to detect the position of impinging of the particles.
The cathode electrodes may be derived from an active pixel sensor array of the type described in U.S. Pat. No. 5,471,215, and as conventional may include various types of on-chip matrix processing. This system may use an electrode sensor of 1024 by 1024 pixels, with sub pixel centroiding and radial integration. The active pixel sensor itself may have a sensitivity on the order of 10 −17 amps. By adding pixel current processing, another two orders of magnitude of sensitivity may be obtained.
Forming the mass spectrometer in this way enables the device to be formed smaller, lighter, and with less cost than other devices of this type. This enables a whole range of applications; such as in situ biomedical sampling. One application is use of the miniature mass spectrometer is for a breathalyzer. Since there are no electron beam filaments and the like, any of the system components can operate at relatively higher pressures, for example 5 to 7 Torr pressures or higher. With a Faraday cup electrometer ion detector, sub femtoamp levels of sensitivity may be obtained. This system could be used as a portable device for finding various characteristics in exhaled breath. For example, detection of carbon monoxide in exhaled breath may be used as a screening diagnostic for diabetes.
Another application of this system is for use in a miniature ion mobility spectrometer as shown in FIG. 3 . Conventional ion mobility spectrometers use a shutter gate. This provides short pulses of ions. The shortened pulses of ions are often limited to about 1 percent of the total number of ions that are available for detection. However, resolution of such a device is related to the width of the ion pulse. The width of the ion pulse cannot be increased without correspondingly decreasing the resolution.
In the improved system of FIG. 3 , total and continuous ionization of sample gas and continuous introduction of all ions into the chamber is enabled. Sample gases are introduced as 600 into the ionization membrane 605 of the type described above. In general, the ionization membrane 605 could include either a single pore device or could have multiple pores within the device.
Ions 610 from the membrane exit the membrane as an ion stream. Electrons in contrast move back behind (that is, to the other side of) the membrane, and may further contribute to the ionization of the incoming gases. The atoms or molecules are carried through the body of the spectrometer by a gas feed system 625 . The gas feed system includes either an upstream carrier gas supply and Venturi sampler, or a downstream peristaltic pump.
The ions are drawn towards the filter electrode 615 which receive alternating and/or swept DC electric fields, for the transverse dispersal of the ions. A repetitive ramping of the DC fields sweeps through the spectrum of ion species.
An important feature of this device is the high field strengths which can be obtained. At moderate field strengths, for example <100,000 volts per meter, the mobility of ions at atmospheric and moderate pressures is constant. However, at higher field strengths, such as 2 million volts per meter or greater, the mobility of the ions is nonlinear. The mobility changes differentially for high and low mobility ions. This change may be, for example, by 20 percent. Therefore, by applying a waveform that is formed of a short high-voltage and a long low or negative voltage to the filter electrodes, the ion species is disbursed between the filter electrodes. This waveform may be selected to provide a zero time averaged field. In operation, the ions are transported laterally by a carrier gas stream. A low strength DC field may be supplied in opposition to the other field. This fields applied to the filter electrode may straighten the trajectory of specific ion species, allowing their passage through the filter. The other ion species collide with the electrodes. Sweeping of the DC field may facilitate detection of the complete ion spectrum.
Detector electrodes 620 are located downstream of the filter electrodes 615 . The selected ions have straightened trajectories, and these detector electrodes 620 deflect the straightened-trajectory ions into detection electrodes, where they are detected. The detected current provides a direct measure of the number of ions. The number of ions is effectively proportional to the vapor concentration.
It should be understood that this gas feed system could be either upstream or downstream in this way.
Another embodiment uses this ionization technique to form a free space ion thruster.
Yet another embodiment describes use of an ionizer of this type in a fuel cell. Previous fuel cell proton exchange membranes have used platinum or other electrooxidation catalysts to facilitate proton transfer. In this system, the oxidation gas or gases 700 is passed through the pores of a membrane 705 under an extreme electric field as shown in FIG. 4 . The oxidation gas or gases 700 are completely ionized on passage through the membrane. The gas 708 once ionized, now has a positively charged aspect. The gas 708 drifts to the membrane 710 where the electrooxidized state of the gas enhances its transfer through the cathode. The transfer of atomic species through the membrane in this way reduces the partial pressure between the ionizer 705 and the membrane 710 , this causing further inflow through the ionizer pores of the oxidation gas 702 . The ionizer potential may alternatively be maintained positive with respect to the cathode membrane in order to accelerate the ions to an increased velocity before imprinting on the cathode membrane which forms the accelerator grid.
Another embodiment, shown in FIG. 5 , uses this ionization membrane as part of a miniature ion thruster. This may form a thrust system using propellant gas. Propellant gas 800 is ionized by passing it through the pores of a membrane 805 of the type described above, under a high electric field. This forms positively charged ions 809 from the gas. The ions 809 enter another field 808 between the membrane and a porous accelerator grid 810 . This other field 808 accelerates the ions to an increased velocity, and expels them from the thruster as 820 .
The electrons are caused to move back behind the membrane where a small electric field and magnetic field may linearly and rotationally accelerate the electron beam around to eject the electrons from the thruster with the same vector but reduced velocity as the ion beam. Since the ion and electron currents are substantially identical, this system becomes effectively charge neutral.
This system may use a small tube 820 of 1.5 cm long; 2 mm in diameter, of dielectric materials such as quartz. The tube 820 may be eutectically bonded to the top of the membrane 805 . The micromachined conductive grid is similarly affixed to the top of the tube. The bottom of the membrane may also be eutecticly bonded to a thruster housing 825 . That housing may contain another accelerating grid 830 and magnets.
An exterior view of the structure is shown in FIG. 6 , which shows the tube for any particular accelerator grid potential, the thrust of the engine is determined by the gas flow through the membrane pores. This system may use a plurality of miniature ionization tubes such as the one described above, that are disbursed across the surface of the structure. These tubes may be deployed individually or collectively by connecting them into a circuit. The ions from each of these tubes are accelerated under the influence of a localized electric field that is along the vector representing the least distance to the peripheral grid. The aggregate thrust is the geometrically integrated mass-momentum of all connected free space ion thrusters.
In this embodiment, a bipolar ion thruster may allow reversing the electrode potentials on the ionization membrane, causing the electrons to pass through the membrane, while ions move behind the membrane. The high velocity ions are expelled from the front of the thruster, and electrons are expelled from the rear of the thruster. This engine can therefore be reversed in this way.
When used in a vacuum, a low-pressure gas may need to be introduced into the membrane aperture that has a velocity sufficient to carry the gas into the ionization field. FIG. 7 shows an illustration of the way gas expands in a vacuum and has its molecules accelerated to supersonic speed while cooling, and directed through the membrane. Once ionized, the accelerating ions will create a partial vacuum behind them, which partial vacuum encourages further gas flow through the membrane. Gas that remains behind the membrane is ionized, and its negative field directs those ions through the membrane.
This system may have many different applications including biomedical applications such as a breath analyzer, as well as applications in other systems. It may have applications environment monitoring, personal monitoring, reviewing of water quality, automobile MAP control, detection of explosives, chemical and biological agent detection, and in an artificial nose type product.
|
A fuel cell is disclosed comprising an ionization membrane having at least one area through which gas is passed, and which ionizes the gas passing therethrough, and a cathode for receiving the ions generated by the ionization membrane. The ionization membrane may include one or more openings in the membrane with electrodes that are located closer than a mean free path of molecules within the gas to be ionized. Methods of manufacture are also provided.
| 8
|
[0001] The present application is a 37 C.F.R. §1.53(b) continuation of U.S. patent application Ser. No. 12/639,872 filed on Dec. 16, 2009, which is a 37 C.F.R. §1.53(b) continuation of U.S. patent application Ser. No. 12/267,457 filed Nov. 7, 2008, currently pending, which is a 37 C.F.R. §1.53(b) continuation of U.S. patent application Ser. No. 10/461,451 filed Jun. 16, 2003, now U.S. Pat. No. 7,533,548 B2, which claims priority to Korean Patent Application No. 85521/2002, filed Dec. 27, 2002, the entire contents of which are hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a drum type washing machine, and more particularly, to a drum type washing machine which can maximize a capacity of a drum without changing an entire size of a washing machine.
[0004] 2. Description of the Related Art
[0005] FIG. 1 is a side sectional view showing a drum type washing machine in accordance with the conventional art, FIG. 2 is a front sectional view showing the drum type washing machine in accordance with the conventional art.
[0006] The conventional drum type washing machine comprises: a cabinet 102 for forming an appearance; a tub 104 arranged in the cabinet 102 for storing washing water; a drum 106 rotatably arranged in the tub 104 for washing and dehydrating laundry; and a driving motor 110 positioned at a rear side of the tub 104 and connected to the drum 106 by a driving shaft 108 thus for rotating the drum 106 .
[0007] An inlet 112 for inputting or outputting the laundry is formed at the front side of the cabinet 102 , and a door 114 for opening and closing the inlet 112 is formed at the front side of the inlet 112 .
[0008] The tub 104 of a cylindrical shape is provided with an opening 116 at the front side thereof thus to be connected to the inlet 112 of the cabinet 102 , and a balance weight 118 for maintaining a balance of the tub 104 and reducing vibration are respectively formed at both sides of the tub 104 .
[0009] Herein, a diameter of the tub 104 is installed to be less than a width of the cabinet 102 by approximately 30-40 mm with consideration of a maximum vibration amount thereof so as to prevent from being contacted to the cabinet 102 at the time of the dehydration.
[0010] The drum 106 is a cylindrical shape of which one side is opened so that the laundry can be inputted, and has a diameter installed to be less than that of the tub 104 by approximately 15-20 mm in order to prevent interference with the tub 104 since the drum is rotated in the tub 104 .
[0011] A plurality of supporting springs 120 are installed between the upper portion of the tub 104 and the upper inner wall of the cabinet 102 , and a plurality of dampers 122 are installed between the lower portion of the tub 104 and the lower inner wall of the cabinet 102 , thereby supporting the tub 104 with buffering.
[0012] A gasket 124 is formed between the inlet 112 of the cabinet 102 and the opening 116 of the tub 104 so as to prevent washing water stored in the tub 104 from being leaked to a space between the tub 104 and the cabinet 102 . Also, a supporting plate 126 for mounting the driving motor 110 is installed at the rear side of the tub 104 .
[0013] The driving motor 110 is fixed to a rear surface of the supporting plate 126 , and the driving shaft 108 of the driving motor 110 is fixed to a lower surface of the drum 106 , thereby generating a driving force by which the drum 106 is rotated.
[0014] In the conventional drum type washing machine, the diameter of the tub 104 is installed to be less than the width of the cabinet 102 with consideration of the maximum vibration amount so as to prevent from being contacted to the cabinet 102 , and the diameter of drum 106 is also installed to be less than that of the tub 104 in order to prevent interference with the tub 104 since the drum is rotated in the tub 104 . According to this, so as to increase the diameter of the drum 106 which determines a washing capacity, a size of the cabinet 102 has to be increased.
[0015] Also, since the gasket 124 for preventing washing water from being leaked is installed between the inlet 112 of the cabinet 102 and the opening 116 of the tub 104 , a length of the drum 106 is decreased as the installed length of the gasket 124 . According to this, it was difficult to increase the capacity of the drum 106 .
SUMMARY OF THE INVENTION
[0016] Therefore, an object of the present invention is to provide a drum type washing machine which can increase a washing capacity without changing an entire size thereof, in which a cabinet and a tub is formed integrally and thus a diameter of a drum can be increased without increasing a size of the cabinet.
[0017] Another object of the present invention is to provide a drum type washing machine which can increase a washing capacity by increasing a length of a drum without increasing a length of a cabinet, in which the cabinet and a tub are formed integrally and thus a location of a gasket is changed.
[0018] To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a drum type washing machine comprising: a cabinet for forming an appearance; a tub fixed to an inner side of the cabinet and for storing washing water; a drum rotatably arranged in the tub for washing and dehydrating laundry; and a driving motor positioned at the rear side of the drum for generating a driving force by which the drum is rotated.
[0019] The tub is a cylindrical shape, and a front surface thereof is fixed to a front inner wall of the cabinet.
[0020] Both sides of the tub are fixed to both sides inner wall of the cabinet.
[0021] A supporting plate for mounting the driving motor is located at the rear side of the tub, and a gasket hermetically connects the supporting plate and the rear side of the tub, in which the gasket is formed as a bellows and has one side fixed to the rear side of the tub and another side fixed to an outer circumference surface of the supporting plate.
[0022] A supporting unit for supporting an assembly composed of the drum, the driving motor, and the supporting plate with buffering is installed between the supporting plate and the cabinet.
[0023] The supporting unit comprises: a plurality of upper supporting rods connected to an upper side of the supporting plate towards an orthogonal direction and having a predetermined length; buffering springs connected between the upper supporting rods and an upper inner wall of the cabinet for buffering; a plurality of lower supporting rods connected to a lower side of the supporting plate towards an orthogonal direction and having a predetermined length; and dampers connected between the lower supporting rods and a lower inner wall of the cabinet for absorbing vibration.
[0024] The drum is provided with a liquid balancer at a circumference of an inlet thereof for maintaining a balance when the drum is rotated.
[0025] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] 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.
[0027] In the drawings:
[0028] FIG. 1 is a side sectional view showing a drum type washing machine in accordance with the conventional art;
[0029] FIG. 2 is a front sectional view showing the drum type washing machine in accordance with the conventional art;
[0030] FIG. 3 is a side sectional view showing a drum type washing machine according to one embodiment of the present invention;
[0031] FIG. 4 is a front sectional view showing the drum type washing machine according to one embodiment of the present invention;
[0032] FIG. 5 is a lateral view showing a state that a casing of the drum type washing machine according to one embodiment of the present invention is cut;
[0033] FIG. 6 is a front sectional view of a drum type washing machine according to a second embodiment of the present invention;
[0034] FIG. 7 is a front sectional view showing a drum type washing machine according to a third embodiment of the present invention;
[0035] FIG. 8 is a longitudinal sectional view of the drum type washing machine according to the third embodiment of the present invention; and
[0036] FIG. 9 is a rear sectional view showing the drum type washing machine according to the third embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
[0038] FIG. 3 is a side sectional view showing a drum type washing machine according to one embodiment of the present invention, and FIG. 4 is a front sectional view showing the drum type washing machine according to one embodiment of the present invention.
[0039] The drum type washing machine according to one embodiment of the present invention comprises: a cabinet 2 for forming an appearance of a washing machine; a tub 4 formed integrally with the cabinet 2 and for storing washing water; a drum 6 rotatably arranged in the tub 4 for washing and dehydrating laundry; and a driving motor 8 positioned at the rear side of the drum 6 for generating a driving force by which the drum 6 is rotated.
[0040] The cabinet 2 is rectangular parallelepiped, and an inlet 20 for inputting and outputting laundry is formed at the front side of the cabinet 2 and a door 10 for opening and closing the inlet 20 is formed at the inlet 20 .
[0041] The tub 4 is formed as a cylinder shape having a predetermined diameter in the cabinet 2 , and the front side of the tub 4 is fixed to the front inner wall of the cabinet 2 or integrally formed at the front inner wall of the cabinet 2 . Both sides of the tub 4 are contacted to both sides inner wall of the cabinet 2 or integrally formed with both sides inner wall of the cabinet 2 thus to be prolonged.
[0042] Herein, since both sides of the tub 4 are contacted to both sides inner wall of the cabinet 2 , a diameter of the tub 4 can be increased.
[0043] Also, the supporting plate 12 is positioned at the rear side of the tub 4 and the gasket 14 is installed between the supporting plate 12 and the rear side of the tub 4 , thereby preventing washing water filled in the tub 4 from being leaked.
[0044] The gasket 14 is formed as a bellows of a cylinder shape and has one side fixed to the rear side of the tub 4 and another side fixed to an outer circumference surface of the supporting plate 12 .
[0045] The supporting plate 12 is formed as a disc shape, the driving motor 8 is fixed to the rear surface thereof, and a rotation shaft 16 for transmitting a rotation force of the driving motor 8 to the drum 6 is rotatably supported by the supporting plate 12 . Also, a supporting unit for supporting the drum 6 with buffering is installed between the supporting plate 12 and the inner wall of the cabinet 2 .
[0046] The supporting unit comprises: a plurality of upper supporting rods 22 connected to an upper side of the supporting plate 12 and having a predetermined length; buffering springs 24 connected between the upper supporting rods 22 and an upper inner wall of the cabinet 2 for buffering; a plurality of lower supporting rods 26 connected to a lower side of the supporting plate 12 and having a predetermined length; and dampers 28 connected between the lower supporting rods 26 and a lower inner wall of the cabinet 2 for absorbing vibration.
[0047] Herein, the buffering springs 24 and the dampers 28 are installed at a center of gravity of an assembly composed of the drum 6 , the supporting plate 12 , and the driving motor 8 . That is, the upper and lower supporting rods 22 and 26 are prolonged from the supporting plate 12 to the center of gravity of the assembly, the buffering springs 24 are connected between an end portion of the upper supporting rod 22 and the upper inner wall of the cabinet 2 , and the dampers 28 are connected between an end portion of the lower supporting rod 26 and the lower inner wall of the cabinet 2 , thereby supporting the drum 6 at the center of gravity.
[0048] A diameter of the drum 6 is installed in a range that the drum 6 is not contacted to the tub 4 even when the drum 6 generates maximum vibration in order to prevent interference with the tub 4 at the time of being rotated in the tub 4 .
[0049] Operations of the drum type washing machine according to the present invention are as follows.
[0050] If the laundry is inputted into the drum 6 and a power switch is turned on, washing water is introduced into the tub 6 . At this time, the front side of the tub 6 is fixed to the cabinet 2 and the gasket 14 is connected between the rear side of the tub 6 and the supporting plate 12 , thereby preventing the washing water introduced into the tub 6 from being leaked outwardly.
[0051] If the introduction of the washing water is completed, the driving motor 8 mounted at the rear side of the supporting plate 12 is driven, and the drum 6 connected with the driving motor 8 by the rotation shaft 16 is rotated, thereby performing washing and dehydration operations. At this time, the assembly composed of the drum 6 , the driving motor, and the supporting plate 12 is supported by the buffering springs 24 and the dampers 28 mounted between the supporting plate 12 and the inner wall of the cabinet 20 .
[0052] FIG. 6 is a front sectional view of a drum type washing machine according to a second embodiment of the present invention.
[0053] The drum type washing machine according to the second embodiment of the present invention has the same construction and operation as that of the first to embodiment except a shape of the tub.
[0054] That is, the tub 40 according to the second embodiment has a straight line portion 42 with a predetermined length at both sides thereof. The straight line portion 42 is fixed to the inner wall of both sides of the cabinet 2 , or integrally formed at the wall surface of both sides of the cabinet 2 .
[0055] Like this, since the tub 40 according to the second embodiment has both sides fixed to the cabinet 2 as a straight line form, the diameter of the tub 40 can be increased. Accordingly, the diameter of the drum 6 arranged in the tub 40 can be more increased.
[0056] FIG. 7 is a front sectional view showing a drum type washing machine according to a third embodiment of the present invention, FIG. 8 is a longitudinal sectional view of the drum type washing machine according to the third embodiment of the present invention, and FIG. 9 is a rear sectional view showing the drum type washing machine according to the third embodiment of the present invention.
[0057] The drum type washing machine according to the third embodiment of the present invention comprises: a cabinet 2 for forming an appearance of a washing machine; a tub 50 formed integrally with the cabinet 2 and for storing washing water; a drum 6 rotatably arranged in the tub 50 for washing and dehydrating laundry; and a supporting unit positioned at the rear side of the tub 50 and arranged between the supporting plate 12 to which the driving motor 8 is fixed and the cabinet 2 for supporting the drum 6 with buffering.
[0058] The tub 50 is composed of a first partition wall 52 fixed to the upper front inner wall and both sides inner wall of the cabinet 2 ; and a second partition wall 54 integrally fixed to the lower front inner wall and both sides inner wall of the cabinet 2 .
[0059] The first partition wall 52 of a flat plate shape is formed at the upper side of the cabinet 2 in a state that the front side and both sides are integrally formed at the inner wall of the cabinet 2 or fixed thereto. Also, the second partition wall 54 of a semi-circle shape is formed at the lower side of the cabinet 2 in a state that the front side and both sides are integrally formed at the inner wall of the cabinet 2 or fixed thereto.
[0060] The supporting unit comprises: a plurality of upper supporting rods 56 connected to the upper side of the supporting plate 12 and having a predetermined length; buffering springs 58 connected between the upper supporting rods 56 and the upper inner wall of the cabinet 2 for buffering; a plurality of lower supporting rods 60 connected to the lower side of the supporting plate 12 and having a predetermined length; and dampers 62 connected between the lower supporting rods 60 and the lower inner wall of the cabinet 2 for absorbing vibration.
[0061] Herein, the upper supporting rods 56 are bent to be connected to the upper side of the supporting plate 12 and positioned at the upper side of the first partition wall 52 , and the buffering springs 58 are connected to the end portion of the upper supporting rods 56 . Also, the lower supporting rods 60 are bent to be connected to the lower side of the supporting plate 12 and positioned at the lower side of the second partition wall 54 , and the dampers 62 are connected to the end portion of the lower supporting rods 56 .
[0062] In the drum type washing machine according to the present invention, a size of the drum can be maximized by fixing the tub in the cabinet, thereby increasing washing capacity of the drum without increasing a size of the cabinet.
[0063] Also, since the front surface of the tub is integrally formed at the inner wall of the cabinet and the gasket is installed between the rear surface of the tub and the supporting plate, a length of the drum can be increased and thus the washing capacity of the drum can be increased.
[0064] As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims.
|
A drum type washing machine is provided. The drum type washing machine may include a cabinet, a tub fixed to an inner side of the cabinet, a drum rotatably arranged in the tub, and a driving motor positioned at a rear side of the drum for generating a driving force that rotates the drum. The washing machine may also include a supporting plate to rotatably support a rotational shaft extending between the motor and the drum, and a plurality of supporters connected between the supporting plate and the cabinet. Such an arrangement may increase washing capacity by increasing a diameter of the drum without increasing an external size of the cabinet.
| 3
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/943,660; filed Jun. 13, 2007, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to medical devices for monitoring vital signs, e.g., blood pressure.
BACKGROUND OF THE INVENTION
[0003] Pulse transit time (PTT), defined as the transit time for a pressure pulse launched by a heartbeat in a patient's arterial system, has been shown in a number of studies to correlate to both systolic and diastolic blood pressures. In these studies, PTT is typically measured with a conventional vital signs monitor that includes separate modules to determine both an electrocardiogram (ECG) and pulse oximetry. During a PTT measurement, multiple electrodes typically attach to a patient's chest to determine a time-dependent ECG component a sharp spike called the ‘QRS complex’. This feature indicates an initial depolarization of ventricles within the heart and, informally, marks the beginning of the heartbeat and pressure pulse that follows. Pulse oximetry is typically measured with a bandage or clothespin-shaped sensor that attaches to a patient's finger, and includes optical systems operating in both the red and infrared spectral regions. A photodetector measures radiation emitted from the optical systems and transmitted through the patient's finger. Other body sites, e.g., the ear, forehead, and nose, can also be used in place of the finger. During a measurement, a microprocessor analyses both red and infrared radiation measured by the photodetector to determine the patient's blood oxygen saturation level and a time-dependent waveform called an optical waveform or photoplethysmograph. Time-dependent features of the optical waveform indicate both pulse rate and a volumetric absorbance change in an underlying artery (e.g., in the finger) caused by the propagating pressure pulse.
[0004] Typical PTT measurements determine the time separating a maximum point on the QRS complex (indicating the peak of ventricular depolarization) and a foot of the optical waveform (indicating the beginning the pressure pulse). PTT depends primarily on arterial compliance, the propagation distance of the pressure pulse (closely approximated by the patient's arm length), and blood pressure. PTT typically relates inversely to blood pressure, i.e., a decrease in PTT indicates an increase in blood pressure.
[0005] A number of issued U.S. Patents describe the relationship between PTT and blood pressure. For example, U.S. Pat. Nos. 5,316,008; 5,857,975; 5,865,755; and 5,649,543 each describe an apparatus that includes conventional sensors that measure an ECG and optical waveform, which are then processed to determine PTT.
[0006] Studies have also shown that a property called vascular transit time (‘VTT’), defined as the time separating two plethysmographs measured from different locations on a patient, can correlate to blood pressure. Alternatively, VTT can be determined from the time separating other time-dependent signals measured from a patient, such as those measured with acoustic or pressure sensors. A study that investigates the correlation between VTT and blood pressure is described, for example, in ‘Evaluation of blood pressure changes using vascular transit time’, Physiol. Meas. 27, 685-694 (2006). U.S. Pat. Nos. 6,511,436; 6,599,251; and 6,723,054 each describe an apparatus that includes a pair of optical or pressure sensors, each sensitive to a propagating pressure pulse, that measure VTT. As described in these patents, a microprocessor associated with the apparatus processes the VTT value to estimate blood pressure.
[0007] In order to accurately measure blood pressure, both PTT and VTT measurements typically require a ‘calibration’ measurement consisting of one or more conventional blood pressure measurements made simultaneously with the PTT or VTT measurement. The calibration accounts for patient-to-patient variation in arterial properties (e.g., stiffness and size). Calibration measurements are typically made with an auscultatory technique (e.g., using a pneumatic cuff and stethoscope) at the beginning of the PTT or VTT measurement; these measurements can be repeated if and when the patient undergoes any change that may affect their physiological state. Once completed, the calibration blood pressure measurements are used, along with a change in PTT, to determine the patient's blood pressure and blood pressure variability.
[0008] Other efforts have attempted to use a calibration along with other properties of the plethysmograph to measure blood pressure. For example, U.S. Pat. No. 6 , 616 , 613 describes a technique wherein a second derivative is taken from a plethysmograph measured from the patient's ear or finger. Properties from the second derivative are then extracted and used with calibration information to estimate the patient's blood pressure. In a related study, described in ‘Assessment of Vasoactive Agents and Vascular Aging by the Second Derivative of Photoplethysmogram Waveform’, Hypertension. 32, 365-370 (1998), the second derivative of the plethysmograph is analyzed to estimate the patient's ‘vascular age’ which is related to the patient's biological age and vascular properties.
SUMMARY OF THE INVENTION
[0009] This invention provides a sensor armband that includes an embedded multi-sensor array and electrode that, together, make a cuffless measurement of blood pressure using PTT. Once measured, the PTT value may be corrected by a property, referred to herein as a ‘vascular index’ (‘VI’), that accounts for the patient's arterial properties (e.g., stiffness and size). VI is typically determined by the shape of the plethysmograph, referred to herein as an ‘optical waveform’, which is measured from the brachial, finger, radial, or ulnar arteries. To accurately measure VI, the optical waveform must be characterized by a high signal strength and signal-to-noise ratio. The multi-sensor array according to the invention measures such a signal because it includes multiple (e.g. three or more) optical modules, wired together and collectively working in concert, to measure a single signal.
[0010] The invention has a number of advantages. In general, the armband described herein uses both PTT and VI to make a cuffless measurement of blood pressure without requiring calibration at the beginning of the measurement. This dramatically simplifies the process of measuring blood pressure on a patient in the hospital and home setting. Moreover, the armband can send information through either a wired or wireless interface to an external device that combines all the data-analysis features and form factor of a conventional PDA. The wireless interface, in particular, increases patient mobility by eliminating the wires that normally tether a patient to a conventional vital signs monitor. Ultimately this results in an easy-to-use, flexible system that performs one-time, continuous, and ambulatory measurements both in and outside of a hospital. Measurements can be made throughout the day with little or no inconvenience to the caregiver or patient.
[0011] These and other advantages are described in detail in the following description, and in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic view of a sensor armband, attached to a patient, including a multi-sensor array and electrode;
[0013] FIG. 2 is a schematic view of the multi-sensor array of FIG. 1 including three optical modules;
[0014] FIG. 3 is a schematic view of the three optical modules of FIG. 2 measuring a patient through several layers of epidermis;
[0015] FIG. 4 is a schematic view of the sensor armband of FIG. 1 featuring electrodes and a multi-sensor array;
[0016] FIG. 5 is a schematic of the front and side views, respectively, of a circuit board and battery housed within the sensor armband of FIG. 4 .
DETAILED DESCRIPTION
[0017] FIG. 1 shows a sensor armband 47 according to the invention featuring a multi-sensor array 30 that measures blood pressure from a patient 40 . During a measurement, the patient's heart 48 generates electrical impulses that pass through the body near the speed of light. These impulses stimulate each heart beat, which in turn generates a pressure wave that propagates through the patient's vasculature at a significantly slower speed. Immediately after the heartbeat, the pressure wave leaves the aorta 49 , passes through the subclavian artery 50 , to the brachial artery 44 , and from there through the radial artery 45 to smaller arteries in the patient's fingers. The armband 47 includes an embedded two-part electrode 70 and connects to a third electrode 42 A, attached to the patient's chest, through a cable 51 A. Collectively, these three electrodes 70 , 42 A measure unique electrical signals which pass to an amplifier/filter circuit within an embedded electronics module. The amplifier/filter circuits are conventional circuits that include analog band-pass filters that typically pass frequencies between 1 and 50 Hz, and conventional amplifiers with fixed or adjustable (e.g. software-controlled) gain. These circuits process the signals to generate an analog electrical signal, similar to a conventional ECG, which is then digitized with an analog-to-digital converter to form the electrical waveform that is stored in memory.
[0018] Using a reflection-mode geometry, the multi-sensor array 30 embedded in the sensor armband 47 measures an optical waveform from the patient's brachial artery. A second optical sensor 80 connected to the electronics module through a cable 51 B can additionally measure a second optical waveform from the patient's radial or ulnar artery; typically the second optical sensor 80 is disposed on the underside of the patient's wrist 57 . These signals are amplified using second and third amplifier/filter circuits, and then digitized with second and third channels within the analog-to-digital converter in the electronics module. Each optical waveform features a time-dependent ‘pulse’ corresponding to each heartbeat that represents a volumetric change in an underlying artery caused by the propagating pressure pulse. The electrical waveform includes a sharp peak corresponding to the QRS complex. PTT is calculated for each heartbeat by measuring the time difference between the peak of the electrical waveform and the foot of at least one optical waveform. An algorithm processes PTT to determine the patient's blood pressure. As described above, PTT and blood pressure typically relate through an inverse, linear relationship.
[0019] The above-described system can be used in a number of different settings, including both the home and hospital. A patient 40 in a hospital, for example, can continuously wear the sensor armband 47 over a time period ranging from minutes to several days. During this period, the sensor armband 47 is powered by a rechargeable battery, and continuously measures blood pressure along with other vital signs. At a predetermined interval (typically, e.g., every few minutes) the sensor armband transmits this information through a short-range wireless interface 12 (e.g., a Bluetooth® interface) to the bedside device 10 , which is typically seated in a docking station 200 next to a bed in the hospital. The docking station 200 allows the device 10 to be easily seen by the patient or caregiver and additionally includes an AC adaptor 202 that plugs into a wall outlet 204 and continuously charges the device's battery as well as a spare battery 201 for the armband 47 . When the original rechargeable battery in the armband is depleted, the caregiver (or patient) 40 replaces it with the spare battery 201 in the docking station 200 . The device 10 is highly portable and can be easily removed from the docking station 200 . It communicates with a nation-wide wireless network (e.g. Sprint) through a long-range wireless interface 13 (e.g., a CDMA modem), or with the Internet 210 through a wired or wireless (e.g., 802.11) interface 205 .
[0020] Each optical module within the multi-sensor array 30 typically includes an LED operating near 570 nm, a photodetector, and an amplifier. This wavelength is selected because it is particularly sensitive to volumetric changes in an underlying artery when deployed in a reflection-mode geometry, as described in the following co-pending patent application, the entire contents of which are incorporated herein by reference: SYSTEM FOR MEASURING VITAL SIGNS USING AN OPTICAL MODULE FEATURING A GREEN LIGHT SOURCE (U.S. Ser. No. 11/307,375; filed Feb. 3, 2006). 570 nm is also particularly effective at measuring optical waveforms from a wide range of skin types featuring different levels of pigmentation. Use of this wavelength is described, for example, in the following technical paper, the contents of which are incorporated herein by reference: ‘Racial Differences in Aortic Stiffness in Normotensive and Hypertensive Adults’, Journal of Hypertension. 17, 631-637, (1999). A preferred optical module is the TRS1755 manufactured by TAOS Inc. of Plano, Tex. (www.taosinc.com). In other embodiments, the integrated optical module can be replaced by one or more stand-alone photodetectors and LEDs operating near 570 nm.
[0021] Typically, three optical modules are used in the multi-sensor array 30 to increase the effective area they irradiate and, consequently, the probability that an underlying or proximal artery is measured. This in turn increases both the strength of the optical signal and its signal-to-noise ratio. Operating in concert, the three sensors collectively measure an optical waveform that includes photocurrent generated by each optical module. The resultant signal forms the optical waveform, and effectively represents an additive or summation signal measured from vasculature (e.g., arteries and capillaries) underneath or proximal to the sensor 30 . The secondary sensor 80 typically includes a similar optical module, and can additionally include LEDs operating near 650 nm and 950 nm to make a pulse oximetry measurement.
[0022] The above-described system determines the patient's blood pressure using PTT, and then corrects this value for VI using the algorithm described below. Specifically, it is well know that a patient's arteries stiffen with biological age. This property can thus be used to estimate the patient's vascular stiffness. When used with a PTT-based measurement of blood pressure, which depends strongly on vascular stiffness, biological age can therefore reduce the need for calibration and increase the accuracy of the blood pressure measurement. The accuracy of the measurement can be further improved with VI, which serves as a proxy for a ‘true’ age of the patient's vasculature: patients with elastic arteries for their age will have a VI lower than their biological age, while patients with stiff arteries for their age will have a VI greater than their biological age. The difference between VI and the patient's biological age can be compared to a pre-determined correction factor to improve the accuracy of a PTT-based blood pressure measurement.
[0023] Co-pending patent applications that describe methods for calculating VI and using it in a PTT-based measurement are described below. Their entire contents are hereby incorporated by reference: 1) VITAL SIGN MONITOR FOR CUFFLESSLY MEASURING BLOOD PRESSURE WITHOUT USING AN EXTERNAL CALIBRATION (U.S. Ser. No. 11/682,228; filed Mar. 5, 2007); 2) VITAL SIGN MONITOR FOR MEASURING BLOOD PRESSURE USING OPTICAL, ELECTRICAL, AND PRESSURE WAVEFORMS (U.S. Ser. No. 12/138,194, filed Jun. 12, 2008); and, 3) VITAL SIGN MONITOR FOR CUFFLESSLY MEASURING BLOOD PRESSURE CORRECTED FOR VASCULAR INDEX (U.S. Ser. No. 12/138,199, filed Jun. 12, 2008).
[0024] Referring to FIGS. 2 and 3 , the multi-sensor array 30 operates collectively using three optical modules 20 , 21 , 22 , each containing an LED 26 , 27 , 28 (typically operating near 570+/−10 nm), a photodetector 23 , 24 , 25 , and a built-in amplifier (not shown in the figure). The modules 20 , 21 , 22 are wired together in parallel using 4 pins total: +Voltage 17 , Ground 16 , Anode 15 , and Signal 18 . With this wiring configuration the modules 20 , 21 , 22 are powered and simultaneously measure a signal from an underlying or proximal artery. Each LED 26 , 27 , and 28 generates radiation near 570 nm, which passes through the epidermis 43 , dermis 41 , and subcutis 42 to irradiate blood flowing in the underlying artery 90 and capillaries 82 a, 82 b. As the heartbeat-induced pressure pulse passes through these flexible vessels, it increases an internal bolus of blood that causes the vessels to temporarily increase in diameter. This, in turn, increases the amount of radiation absorbed according to Beer's Law, and decreases the amount of reflected radiation that irradiates each of the three photodetectors 23 , 24 , 25 . In response to the incident light, each the three photodetectors 23 , 24 , 25 generate photocurrent that is amplified by the built-in amplifier. Each photodetector 23 , 24 , 25 may collect reflected light that originates from an LED 26 , 27 , 28 contained in any of the optical modules 20 , 21 , 22 . Preferably the modules 20 , 21 , 22 are spaced within 1-2 mm so that this occurs. Once light is collected by the photodetector 23 , 24 , 25 , the built-in amplifier in each optical module amplifies the resultant photocurrent to generate a unique optical waveform 31 , 32 , and 33 (note: the waveforms shown in FIG. 2 increase in intensity with each heartbeat, and thus represent the inverse of the signal measured at the photodetector). Photocurrent representing each waveform 31 , 32 , 33 merges within the signal 18 line to form a collective signal 35 that then passes to the amplifier/filter circuit within the armband's electronics module for further processing. This yields a filtered, digital optical waveform, which is then processed as described above for the PTT measurement of blood pressure.
[0025] As shown in FIGS. 4 and 5 , the armband 47 features a low-profile housing 120 that includes electrodes 70 a, 70 b and the multi-sensor array 30 . The housing 120 is typically made of a flexible rubber or plastic and may be either disposable or non-disposable. During a measurement, the armband 47 is strapped to a patient's arm using a flexible strap (not shown in the figure) that connects to molded D-ring connectors 152 , 154 on each side of the housing 120 . In this configuration the multi-sensor array 30 and electrodes 70 a, 70 a contact the patient's skin to measure the optical and electrical waveforms as described above. Note that multi-sensor array 30 and electrodes 70 a, 70 a are all arranged on a surface of the housing that is held up against the patient's arm when the armband is strapped to the patient's arm.
[0026] A main circuit board 161 , powered by two rechargeable AA batteries 162 a, 162 b, supports surface-mounted electronic components within the housing 30 . Computer code that controls the armband's various functions and algorithms runs on a high-end microprocessor 160 , typically an ARM 9 processor (manufacturer: Atmel; part number: AT91SAM9261-CJ) contained in a ‘ball grid array’ package. Before being processed by the microprocessor 160 , analog signals from the multi-sensor array 30 and electrodes 70 a, 70 b pass to an analog-to-digital converter 165 , which is typically a separate integrated circuit (manufacturer: Texas Instruments; part number: ADS8344NB) that digitizes the waveforms at 1 KHz with 16-bit resolution. Such high resolution is required to adequately process the optical and electrical waveforms and generate an accurate PTT value. Once digitized, the waveforms can be stored in memory 175 external to the memory in the microprocessor 160 for further processing.
[0027] The armband 47 additionally includes an embedded, short-range wireless Bluetooth® transceiver 163 to wirelessly transmit blood pressure and other information to an external device through an on-board ceramic antenna 169 (manufacturer: BlueRadios; part number: BR-C40A). The Bluetooth® transceiver 163 can be replaced with an alternative wireless transceiver that operates on a wireless local-area network, such as a WiFi® transceiver (manufacturer: DPAC; part number: WLNB-AN-DP101). Wired connections to, e.g., computers are made with a standard mini-USB connection 151 .
[0028] A number of additional approaches can be used to calculate blood pressure from PTT measured as described above. Such method are described in the following co-pending patent applications, the contents of which are incorporated herein by reference: 1) CUFFLESS BLOOD-PRESSURE MONITOR AND ACCOMPANYING WIRELESS, INTERNET-BASED SYSTEM (U.S. Ser. No. 10/709,015; filed Apr. 7, 2004); 2) CUFFLESS SYSTEM FOR MEASURING BLOOD PRESSURE (U.S. Ser. No. 10/709,014; filed Apr. 7, 2004); 3) CUFFLESS BLOOD PRESSURE MONITOR AND ACCOMPANYING WEB SERVICES INTERFACE (U.S. Ser. No. 10/810,237; filed Mar. 26, 2004); 4) VITAL SIGN MONITOR FOR ATHLETIC APPLICATIONS (U.S. Ser. No. filed Sep. 13, 2004); 5) CUFFLESS BLOOD PRESSURE MONITOR AND ACCOMPANYING WIRELESS MOBILE DEVICE (U.S. Ser. No. 10/967,511; filed Oct. 18, 2004); 6) BLOOD PRESSURE MONITORING DEVICE FEATURING A CALIBRATION-BASED ANALYSIS (U.S. Ser. No. 10/967,610; filed Oct. 18, 2004); 7) PERSONAL COMPUTER-BASED VITAL SIGN MONITOR (U.S. Ser. No. 10/906,342; filed Feb. 15, 2005); 8) PATCH SENSOR FOR MEASURING BLOOD PRESSURE WITHOUT A CUFF (U.S. Ser. No. 10/906,315; filed Feb. 14, 2005); 9) PATCH SENSOR FOR MEASURING VITAL SIGNS (U.S. Ser. No. 11/160,957; filed Jul. 18, 2005); 10) WIRELESS, INTERNET-BASED SYSTEM FOR MEASURING VITAL SIGNS FROM A PLURALITY OF PATIENTS IN A HOSPITAL OR MEDICAL CLINIC (U.S. Ser. No. 11/162,719; filed Sep. 9, 2005); 11) HAND-HELD MONITOR FOR MEASURING VITAL SIGNS (U.S. Ser. No. 11/162,742; filed Sep. 21, 2005); 12) CHEST STRAP FOR MEASURING VITAL SIGNS (U.S. Ser. No. 11/306,243; filed Dec. 20, 2005); 13) SYSTEM FOR MEASURING VITAL SIGNS USING AN OPTICAL MODULE FEATURING A GREEN LIGHT SOURCE (U.S. Ser. No. 11/307,375; filed Feb. 3, 2006); 14) BILATERAL DEVICE, SYSTEM AND METHOD FOR MONITORING VITAL SIGNS (U.S. Ser. No. 11/420,281; filed May 25, 2006); 15) SYSTEM FOR MEASURING VITAL SIGNS USING BILATERAL PULSE TRANSIT TIME (U.S. Ser. No. 11/420,652; filed May 26, 2006); 16) BLOOD PRESSURE MONITOR (U.S. Ser. No. 11/530,076; filed Sep. 8, 2006); 17) TWO-PART PATCH SENSOR FOR MONITORING VITAL SIGNS (U.S. Ser. No. 11/558,538; filed Nov. 10, 2006); and, 18) MONITOR FOR MEASURING VITAL SIGNS AND RENDERING VIDEO IMAGES (U.S. Ser. No. 11/682,177; filed Mar. 5, 2007).
[0029] Other embodiments are also within the scope of the invention. For example, the system is not limited to three optical modules. Additional optical modules could be added to further strengthen the magnitude of the optical waveform. Also, the optical modules within the multi-sensor array are not limited to the ‘linear’ form factor shown in FIG. 2 . The modules, for example, may be placed in a circular configuration, may be offset from one another, or may be fashioned in a random distribution to irradiate a relatively large area of underlying skin. Such a configuration may be desirable for patients with darker pigment. In other embodiments, additional electrodes may be added to strengthen the electrical waveform.
[0030] Still other embodiments are covered by the following claims.
|
A sensor for monitoring a patient's blood pressure, the sensor including a housing unit with a back surface and which includes: a pair of electrodes mounted on the back surface; an optical system mounted on the back surface and including at least one light source that emits optical radiation near 570 nm and at least one photodetector; a first amplifier which generates an analog electrical waveform from the electrical signals from the electrodes; a second amplifier that generates an analog optical waveform from the optical signal from the photodetector; analog-to-digital converter circuitry configured to receive the analog electrical waveform and generate a digital electrical waveform therefrom and to receive the analog optical waveform and generate a digital optical waveform therefrom; and a processor programmed to receive the digital electrical and optical waveforms and determine a pulse transit time for the patient which is a measure of a separation in time of a first feature of the digital electrical waveform and a second feature of the digital optical waveform and to use the pulse transit time to determine a blood pressure value for the patient.
| 0
|
PRIORITY
[0001] The present invention claims priority to PCT patent application PCT/CN2013/083379, which has a filing date of Sep. 12, 2013. The present invention claims priority to Chinese patent application 201210375871, which has a filing date of Sep. 28, 2012.
FIELD OF THE INVENTION
[0002] This invention relates to fuel cell mixed power supply energy management method.
BACKGROUND
[0003] Through retrieving existing technologies, the following literatures are retrieved:
[0004] The fuel cell power supply control principle publicized by the invention patent application of China called “power distribution method for fuel cell mixed power system” with application number “200310103253.3”: Adopt SOC calculation to control according to measurement load control signal (such as throttle signal) and power cell SOC (state of charge) the output of the fuel cell DCDC to satisfy the energy demands of the load system, fuel cell system and power cell pack under the state of charge.
[0005] The fuel cell power supply control method publicized by the invention patent application of China called “fuel cell based mixed power device energy management system” with application number “201010108281.4” also adopts SOC calculation, where,
[0006] Here is the calculation formula for the state of charge (SOC):
[0000] soc( k )=( BC ×soc( k− 1)−∫ k-1 k i out dt+∫ k-1 k i out dt )/ BC
[0007] In the above calculation formula, BC represents cell capacity, soc(k) represents the SOC value of cell at current moment, soc(k-1) represents the SOC value at the previous moment, i out represents cell discharging current and i in represents cell charging current.
[0008] It is known from the above formula that the SOC calculation is a kind of algorithm to obtain the state of charge (SOC) of battery according to the battery current data collected, the cell capacity data set, based on the integration algorithm and by correcting according to the actual cell capacity, cell voltage, temperature at the time of actual use. That invention application has the following disadvantages:
[0009] 1. All the above control method relies on SOC calculation; and the SOC calculation relies on accurate current data, the accuracy of current data depends on the accuracy, sensitivity, stability of current measurement device; however, the current measurement device also has an error; therefore, the SOC calculation method can only be an approximate estimation of the state of charge of the energy storage device. The existing fuel cell system on board vehicle using the SOC calculating method adopts a dual-range current sensor in order to obtain a relatively accurate current value; however, a dual-range current sensor is unable to cover the whole range and at the same time is also unable to avoid the zero drift that the current sensor has, therefore, the current senor has to be calibrated frequently. In this circumstance, a fuel cell company, after selling a fuel cell system on board vehicle, has to calibrate regularly the current measurement device sensor. The product immaturity will directly influence the mercerization progress of fuel cell vehicles.
[0010] 2. The capacity of the energy storage device (battery) may reduce with use gradually. It is known from the formula that in order to obtain SOC accurately, it is imperative to have an accurate capacity value of the energy storage device. Therefore, it is imperative to calibrate the capacity of the energy storage device (battery), which can only be a vague estimation. Therefore, it is unable to accurately conduct the fuel cell system energy management by adopting the SOC calculation method.
[0011] 3. The current output fluctuation amplitude is large when a forklift is working.
[0012] The voltage of the energy storage device (battery) used on fuel cell bus, fuel cell car as auxiliary power is often hundreds of volts, the current range is from negative tens of amperes to positive tens of amperes; under the circumstance that the current range is small, the accuracy of battery current value is relatively high, under this working condition, though the use of the SOC calculation method is not so good as the said fuel cell mixed power supply energy management method, it is barely satisfactory.
[0013] The voltage of the energy storage device (battery) used on fuel cell forklift as auxiliary power is often tens of volts, but the current range fluctuates largely. For example, the common nominal voltage 24V corresponds to a working current range −500˜500 A; the nominal voltage 36V corresponds to a working current range −800˜1000 A, the nominal voltage 48V corresponds to a current range −600˜800 A. This is because when a fuel cell forklift is working, it constantly lifts loads, drives at an accelerated speed, brakes, etc. that result in the output current of the battery increasing from several amperes gradually to hundreds of amperes and even a thousand amperes and turning from outputting a thousand amperes to inputting hundreds of amperes. As the current range is large, it is very difficult to measure the current value accurately; at the same time, that the current output fluctuation frequency is high when a forklift is working further makes real-time and accurate current measurement become very difficult; and SOC integration algorithm can also amplify the deviation constantly. Therefore, it is unable to realize an accurate fuel cell system energy management by adopting the SOC calculation method on a fuel cell forklift.
[0014] 4. Energy recovery issue, protection issue.
[0015] When a fuel cell vehicle with an energy recovery system (such as the invention patent application called “power distribution method for fuel cell mixed power system” with application number “200310103253.3”) brakes for energy recovery, the energy resulting from braking is input in the energy storage device with a current being often as high as hundred of amperes and even up to 1000 A in some cases, then the voltage of the energy storage device will increase sharply, at the same time, the internal resistances of cables, connections, relays, etc. in the circuits through which current passes at recovery braking can all cause the vehicle voltage to rise; if the battery voltage exceeds the protection voltage of the energy storage device, or the vehicle voltage exceeds the protection voltage of the vehicle, the system or vehicle may disconnect the relay making external connection to realize equipment protection. As a result of disconnecting the relay, the energy storage device is unable to continue to absorb the braking energy and braking can not proceed normally. The vehicle may be out of control and even have an accident. In order that at energy recovery, the voltage of the energy storage device does not exceed the protection voltage of the energy storage device, or the vehicle voltage does not exceed the protection voltage of the vehicle, it is imperative to control the actual state of charge (SOC) of the energy storage device to be a right or a lower value.
[0016] However, as the SOC calculation is based on the measured battery current value and the actual battery capacity and as the battery current data, the actual battery capacity can not be measured accurately, it results in the SOC calculation method being unable to obtain the actual SOC values. When the SOC measurement value is lower than the actual value, the actual state of charge (SOC) of the energy storage device is at a high value, the voltage of the energy storage device will exceed the protection voltage of the energy storage device or the protection voltage of the vehicle; this will constitute a safety hazard to the fuel cell vehicle.
[0017] The said fuel cell mixed power supply energy management method is to control the output current of the DCDC converting unit, respond to the energy demand resulting from load condition change and at the same time ensure the energy storage device to be in a best state of charge according to the measured voltage of the energy storage device and the actual current output by the DCDC converting unit under the circumstance without connecting the vehicle operation input signal (throttle, brake) and calculating SOC.
SUMMARY
[0018] The said fuel cell mixed power supply energy management method includes the following steps:
[0019] Step S 201 : Initialize, specifically, obtain the following parameter values first:
The first current setting of DCDC Isetmin, The first voltage setting of energy storage device Umax, The second voltage setting of energy storage device Umin, The permissible DCDC current deviation value Ipermissible, The maximum current setting that DCDC allows to output Imax,
Then let the current setting of DCDC Iset equal to the said first current setting of DCDC Isetmin;
[0025] Step S 202 : Obtain the energy storage device voltage Ustorage and the actual output current of DCDC converting unit Idcdc, calculate according to the following formula (1) DCDC current deviation value Ideviation:
[0000] I deviation= I set− Idcdc Formula (1);
[0026] Step S 203 : in case of meeting the following circumstances, enter into Step S 204 , Step S 205 or Step S 206 :
If the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax, then enter into Step S 204 , If the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin, then enter into Step S 205 , If the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible, then enter into Step S 206 , If the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and the DCDC current deviation value Ideviation is less than the permissible DCDC current deviation value Ipermissible, then enter into Step S 207 ;
[0031] Step S 204 : If the current setting of DCDC Iset is greater than the first current setting of DCDC Isetmin, then gradually reduce the current setting of DCDC Iset, and then enter into Step S 207 ; if the current setting of DCDC Iset is less than or equal to the first current setting of DCDC Isetmin, then let the current setting of DCDC Iset is equal to the said first current setting of DCDC Isetmin and then enter into Step S 207 ;
[0032] Step S 205 : If the current setting of DCDC Iset is less than the maximum current setting that DCDC allows to output Imax, increase the current setting of DCDC Iset and then enter into Step S 207 ; if the current setting of DCDC Iset is greater than or equal to the maximum current setting that DCDC allows to output Imax, let the current setting of DCDC Iset equal to the maximum current setting that DCDC allows to output Imax and then enter into Step S 207 ;
[0033] Step S 206 : If the current setting of DCDC Iset is greater than the first current setting of DCDC Isetmin, reduce at a fastest speed the current setting of DCDC Iset and then enter into Step S 207 ; if the current setting of DCDC Iset is less than or equal to the first current setting of DCDC Isetmin, let the current setting of DCDC Iset equal to the said first current setting of DCDC Isetmin and then enter into Step S 207 ;
[0034] Step S 207 : Send a current setting instruction to DCDC converting unit, in which the said current setting instruction is used to set the output current of the DCDC converting unit as the current setting of DCDC Iset and then return to Step S 202 .
[0035] Preferably, before the said Step S 201 , the following steps executed in proper order are also included:
[0036] Step A 1 : Determine the limit voltage Ulim, specifically, judge if the highest limit of load protection voltage is greater than the charging protection voltage of the energy storage device; if the judgment result is positive, set the limit voltage Ulimit as equal to the charging protection voltage of the energy storage device; if the judgment result is negative, set the limit voltage Ulimit as equal to the highest limit of load protection voltage;
[0037] Step A 2 : Determine the expected DCDC converting unit output current Iexpect according to the following formula (2):
[0000]
Iexpect
=
Irated
·
Edcdc
U
lim
[0038] Where Irated is the rated output power of the fuel cell, Edcdc is the efficiency of the DCDC converting unit;
[0039] Step A 3 :
[0040] On the current curve using expected DCDC converting unit output current as a constant charging value, obtain the corresponding charging capacity as 50%˜90% of the voltage interval, select any voltage value in the voltage interval as the first voltage setting of energy storage device Umax.
[0041] Preferably, in the said Step A 3 , from the corresponding charging capacity being any voltage value or voltage interval below, set the said voltage value as or select any voltage value in the said voltage interval as the first voltage setting of energy storage device Umax:
The corresponding charging capacity is the voltage value at 90%, determine the voltage value at the said 90% as the first voltage setting of energy storage device Umax, The corresponding charging capacity is 60%˜80% voltage interval, select any voltage value in the said 60%˜80% voltage interval to be determined as the first voltage setting of energy storage device Umax, The corresponding charging capacity is 80%˜90% voltage interval, select any voltage value in the said 80%˜90% voltage interval to be determined as the first voltage setting of energy storage device Umax, The corresponding charging capacity is 50%˜60% voltage interval, select any voltage value in the said 50%˜60% voltage interval to be determined as the first voltage setting of energy storage device Umax.
[0046] Preferably, before the said Step S 201 , the following steps executed in proper order are also included:
[0047] Step B 1 : Determine the system limit charging current, specifically,
[0048] Under the working condition in which the system uses medium limit energy recovery, first use battery to make a braking action and obtain the system current, time data from braking to the end, the negative current of that system is the charging current, calculate the average of that charging current as the system limit charging current;
[0049] Step B 2 : Determine the limit voltage Ulim, specifically, judge if the highest limit of load protection voltage is greater than the charging protection voltage of the energy storage device; if the judgment result is positive, set the limit voltage Ulimit as equal to the charging protection voltage of the energy storage device; if the judgment result is negative, set the limit voltage Ulimit as equal to the highest limit of load protection voltage;
[0050] Step B 3 : Determine the expected DCDC converting unit output current Iexpect according to the following formula (2):
[0000]
Iexpect
=
Irated
·
Edcdc
U
lim
[0051] Where Irated is the rated output of the fuel cell, Edcdc is the efficiency of the DCDC converting unit;
[0052] Step B 4 : Inquire the testing curves of different charging currents and charging capacitances; according to the constant current charging curve that the system limit charging current corresponds to, obtain the corresponding charging capacitance when charging to the limit voltage; according to that charging capacity, look up the corresponding voltage value on the constant current charging curve that the expected DCDC converting unit output current Iexpect corresponds to, the said corresponding voltage value is the first voltage setting of energy storage device Umax;
[0053] Step B 5 : According to the energy recovery working condition when the system uses time limit,do actual testing by using the system controlled by the first voltage setting of energy storage device Umax, correct the first voltage setting of energy storage device Umax so that the actually measured highest voltage is slightly lower than the limit voltage Ulim;
[0054] Step B 6 : Correct the capacity of the energy storage device, specifically, according to the relational curve between energy storage device charging capacity/rated capacity and cycle times, or the relational curve between the discharging capacity/rated capacity and cycle times, inquire the charging capacity/rated capacity ratio after multiple cycles, and then take the product of the first voltage setting of energy storage device Umax and the charging capacity/rated capacity ratio as the corrected first voltage setting of energy storage device Umax.
[0055] Preferably, before the said Step S 201 , the following steps executed in proper order are also included:
[0056] Step C 1 : Determine the minimum consumption current of the auxiliary system Is, specifically, use the system controlled by the first voltage setting of energy storage device Umax to have the system be in an idle condition, after the system becomes stable, the consumption of the auxiliary system reduces to the minimum, measure the current of the auxiliary system at this time, which is the minimum consumption current;
[0057] Step C 2 : take the product of the minimum consumption current of the auxiliary system and the coefficient K as the first current setting of DCDC Isetmin, where the coefficient K is less than 1.
[0058] Preferably, the coefficient K is 0.6.
[0059] Preferably, before the said Step S 201 , the following steps executed in proper order are also included:
[0060] Step D 1 : Determine according to the follow formula (3) the maximum current setting that DCDC allows to output Imax:
[0000]
I
max
=
Irated
·
Edcdc
U
max
[0061] Preferably, before the said Step S 201 , the following steps executed in proper order are also included:
[0062] Step E 1 : Determine according to the following formula (4) the capacitance at the minimum load Cmin:
[0000] C min= C −( Is−I setmin )· T
[0063] Where, C is the charging capacity, Is is the minimum consumption current of the auxiliary system, T is time, the said charging capacity is the charging capacity that the first voltage setting of energy storage device Umax corresponds to inquired on the charging capacity and charging voltage curve with constant current charging taking the maximum current setting that DCDC allows to output Imax as the current, the said time is set according to the response speed that the system requires;
[0064] Step E 2 : According to the capacitance at minimum load Cmin, inquire the charging voltage that the capacitance at the minimum load Cmin corresponds to on the charging capacity and charging voltage curve with constant current charging taking the maximum current setting that DCDC allows to output Imax as the current, select that charging voltage as the second voltage setting of energy storage device Umin.
[0065] This invention provides a fuel cell mixed power supply energy management method. The said method is to control the output current of the DCDC converting unit, respond to the energy demand resulting from load condition change and at the same time ensure the energy storage device to be in a best state of charge according to the measured voltage of the energy storage device and the actual current output by the DCDC converting unit under the circumstance without connecting the vehicle operation input signal (throttle, brake) and calculating SOC.
[0066] In comparison with the existing technology, the said fuel cell mixed power supply energy management method has the following beneficial effects:
1. Improve the fault-tolerant capability of the system. As the control method no longer adopts the SOC calculation mode, the system no longer relies on the accuracy, reliability of the current sensor. 2. Strong compatibility. By setting the charging current condition at a limit condition, the same system is applicable to more models of different vehicles (forklift) and no parameter correction is necessary. 3. High reliability. By setting parameters beforehand to correct in advance the reduction in batter capacity, the long-term system reliability is ensured. The said fuel cell mixed power supply energy management method also uses the data of the energy storage device in determining parameters. These data are that measured in laboratory under a stable working condition; and in the existing system using the SOC calculation mode, the data of the energy storage device is calculated on real-time basis when the system is working, which a kind of dynamic estimation with the accuracy is being not satisfactory. 4. Stable output voltage. The system controls the energy storage device voltage near the first voltage setting of energy storage device Umax, the second voltage setting of energy storage device Umin, this favors to extend the service life to use the vehicle equipment, the energy storage device. 5. Strong practicality. The said fuel cell mixed power supply energy management method is obtained by conducting a lot of actual tests and verifications on multiple models of forklift fuel cells and constant adjustment. A verification was also made on the fuel cell system of a tourist coach. It can not only be used on vehicles, but also adapts to a power supply system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0072] By reading and referring to the detailed descriptions made to the non-restrictive embodiment examples by the following attached figures, other characteristics, purposes and advantages of this invention will become more evident:
[0073] FIG. 1 is the general framework flow chart of the first fuel cell mixed power supply energy management method;
[0074] FIG. 2 is the flow chart of the second type of fuel cell mixed power supply energy management method;
[0075] FIG. 3 is the flow chart of the third type of fuel cell mixed power supply energy management method;
[0076] FIG. 4 is the flow chart of the forth type of fuel cell mixed power supply energy management method;
[0077] FIG. 5 is the flow chart of the fifth type of fuel cell mixed power supply energy management method;
[0078] FIG. 6 is the schematic diagram of current curve of the DCDC converting unit output current with charging expected at a constant value;
[0079] FIG. 7 is the system limit current test curve;
[0080] FIG. 8 is the schematic diagram for selecting the first voltage setting of energy storage device Umax;
[0081] FIG. 9 is the schematic diagram for the process of correcting the first voltage setting of energy storage device Umax;
[0082] FIG. 10 is the curve for the relation between energy storage device charging capacity/rated capacity and cycle times;
[0083] FIG. 11 is the schematic diagram of the structure of the compact type fuel cell supply system of the first embodiment example provided according to this invention;
[0084] FIG. 12 is the specific structural schematic diagram of the DCDC converting unit in the compact type fuel cell supply system as shown in FIG. 11 ;
[0085] FIG. 13 shows the schematic diagram of the high-power diode position in the compact type fuel cell supply system of a preferable case of the first embodiment example provided according to this invention;
DETAILED DESCRIPTION
[0086] A detailed description to this invention is to be made below by combining with specific embodiment examples. The following embodiment examples will help the technical personnel in this field further understand this invention, but it does not limit this invention in any form. It should be pointed out that for ordinary technical people in this field, adjustments and changes can also be made under the prerequisite of not being divorced from the conceiving of this invention. All these belong to the protection scope of this invention.
[0087] FIG. 1 is the general framework flow chart of the first fuel cell mixed power supply energy management method; specifically, in this embodiment example, Step S 201 is executed first to initialize, more specifically, to obtain the parameters set by the system, such parameters include the first current setting of DCDC Isetmin, the first voltage setting of energy storage device Umax, the second voltage setting of energy storage device Umin, the permissible DCDC current deviation value Ipermissible, the maximum current setting that DCDC allows to output Imax, and then let the current setting of DCDC Iset equal to the said first current setting of DCDC Isetmin, where the said energy storage device can be a high energy lithum ion cell and a high capacity super capacitor, etc.
[0088] Next Step S 202 is executed to obtain the energy storage device voltage Ustorage and the actual output current of the DCDC converting unit Idcdc. The DCDC current deviation value Ideviation is calculated according to the following formula (1):
[0000] I deviation= I set− Idcdc Formula (1);
[0089] Then Step S 203 is executed: enter into Step S 204 , Step S 205 or Step S 206 correspondingly if the following conditions are met:
If the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax, then enter into Step S 204 , If the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin, then enter into Step S 205 , If the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible, then enter into Step S 206 , If the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and the DCDC current deviation value Ideviation is less than the permissible DCDC current deviation value Ipermissible, then enter into Step S 207 ;
[0094] In which for Step S 204 : if the current setting of DCDC Iset is greater than the first current setting of DCDC Isetmin, reduce gradually the current setting of DCDC Iset and then enter into Step S 207 ; if the current setting of DCDC Iset is less than or equal to the first current setting of DCDC Isetmin, let the current setting of DCDC Iset equal to the said the first current setting of DCDC Isetmin and then enter into Step S 207 ;
[0095] Step S 205 : If the current setting of DCDC Iset is less than the maximum current setting that DCDC allows to output Imax, increase the current setting of DCDC Iset and then enter into Step S 207 ; if the current setting of DCDC Iset is greater than or equal to the maximum current setting that DCDC allows to output Imax, let the current setting of DCDC Iset equal to the maximum current setting that DCDC allows to output Imax and then enter into Step S 207 ;
[0096] Step S 206 : If the current setting of DCDC Iset is greater than the first current setting of DCDC Isetmin, reduce at the fastest speed the current setting of DCDC Iset and then enter into Step S 207 ; if the current setting of DCDC Iset is less than or equal to the first current setting of DCDC Isetmin, let the current setting of DCDC Iset equal to the said the first current setting of DCDC Isetmin and then enter into Step S 207 ;
[0097] Step S 207 : Send a current setting instruction to DCDC converting unit, where the said current setting instruction is used to set the output current of the DCDC converting unit as the current setting of DCDC Iset and then return to Step S 202 .
[0098] FIGS. 5 to 8 show the flow charts of type 1 to type 4 fuel cell mixed power supply energy management methods. The technical people in this field can can understand the embodiment examples as shown in FIGS. 5 to 8 as 4 preferable cases of the embodiment examples as shown in FIG. 11 , specifically, such 4 preferable cases show 4 types of different embodiments of the said Step S 203 in FIG. 11 .
[0099] For example, in FIG. 12 , first judge if “the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin”, if the judgment result is negative, judge “if the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax” next, if the judgment result is negative again, then judge “if the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible”. In which, the technical people in this field understand that when the said energy storage device voltage Ustorage is greater than the first voltage setting of energy storage device Umax or less than the first voltage setting of energy storage device Umin, the DCDC current deviation value Ideviation is not greater than the permissible DCDC current deviation value Ipermissible.
[0100] Again for example, in FIG. 13 , first judge “if the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax”, if the judgment result is negative, then judge “if the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin” next, if the judgment result is negative again, then judge “if the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible”.
[0101] Again for example, in FIG. 4 , first judge “if the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and if the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible”, if the judgment result is negative, then judge “if the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin” next, if the judgment result is negative again, then judge “if the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax”.
[0102] Again for example, in FIG. 5 , first judge “if the energy storage device voltage Ustorage is less than the first voltage setting of energy storage device Umax and greater than the first voltage setting of energy storage device Umin, and if the DCDC current deviation value Ideviation is greater than or equal to the permissible DCDC current deviation value Ipermissible”, if the judgment result is negative, then judge “if the energy storage device voltage Ustorage is greater than or equal to the first voltage setting of energy storage device Umax” next, if the judgment result is negative again, then judge “if the energy storage device voltage Ustorage is less than or equal to the first voltage setting of energy storage device Umin”.
[0103] In a preferable case of this embodiment example, before the said Step S 201 , parameters are determined in the following way: the first voltage setting of energy storage device Umax, the second voltage setting of energy storage device Umin, the permissible DCDC current deviation value Ipermissible and the maximum current setting that DCDC allows to output Imax.
[0104] A. In case of system having no energy recovery (adopt a mechanical brake, brake by using the friction between brake block and hub, consume the energy resulting from braking), the steps to determine the first voltage setting of energy storage device Umax are shown below:
[0105] Step A 1 : Determine the limit voltage Ulim, specifically, judge if the highest limit of load protection voltage is greater than the charging protection voltage of the energy storage device; if the judgment result is positive, set the limit voltage Ulimit as equal to the charging protection voltage of the energy storage device; if the judgment result is negative, set the limit voltage Ulimit as equal to the highest limit of load protection voltage; where, the load protection voltage is a range value, the charging protection voltage of the energy storage device is a numerical value, all of which are to be supplied by the supplier.
[0106] Step A 2 : Determine the expected DCDC converting unit output current Iexpect according to the following formula (2):
[0000]
Iexpect
=
Irated
·
Edcdc
U
lim
[0107] Where, Irated is the rated output power of the fuel cell, Edcdc is the efficiency of the DCDC converting unit;
[0108] Step A 3 :
[0109] On the current curve using expected DCDC converting unit output current as a constant charging value, obtain the corresponding charging capacity as 50%˜90% voltage interval, select any voltage value in that voltage interval as the first voltage setting of energy storage device Umax. Where, (the current curve with the said expected DCDC converting unit output current as a constant charging value can be supplied by the cell supplier, If there is no right data, approximate currents can be used for replacement, or the curve can be obtained by fitting according to the data at other currents. For example, the curve as shown in FIG. 6 ).
[0110] Further preferably, in the said Step A 3 , different charging capacities were selected according to different energy storage devices, different service life requirements. Specifically, from the corresponding charging capacity being as any following voltage value or voltage interval, determine the said voltage value as or select any voltage value of the said voltage interval as the first voltage setting of energy storage device Umax:
For a system with a super capacitor and fuel cell, the corresponding charging capacity is the voltage value at 90%, determine the voltage value at the said 90% as the first voltage setting of energy storage device Umax, For battery and fuel cell being used as a power system (for example, vehicle), the corresponding charging capacity is 60%˜80% voltage interval, select any voltage value of the said 60%˜80% voltage interval to be determined as the first voltage setting of energy storage device Umax; For battery (with a poor high current discharging capacity) and fuel cell being used as a power system (for example, vehicle), the corresponding charging capacity is 80%˜90% voltage interval, select any voltage value of the said 80%˜90% voltage interval to be determined as the first voltage setting of energy storage device Umax, For battery and fuel cell being used as a non-power system (for example, a power supply for communication base), the corresponding charging capacity is 50%˜60% voltage interval, select any voltage value of the said 50%˜60% voltage interval to be determined as the first voltage setting of energy storage device Umax to maintain a super long service life.
[0115] B. In case of a system with energy recovery, the steps to determine the first voltage setting of energy storage device Umax are shown below:
[0116] Step B 1 : Determine the system limit charging current, specifically, under the energy recovery working condition in which the system uses a medium limit (for example, a forklift brakes with the heaviest weight lifted, the highest slope (a permissible slope circumstance for forklift), accelerating down a slope to the end thereof), use batter first to make a braking action to obtain the system current, time data from braking until its end, as shown in FIG. 7 , the negative current of that system is the charging current, calculate the average of that charging current as the system limit charging current;
[0117] Step B 2 : Determine the limit voltage Ulim, specifically, judge if the highest limit of load protection voltage is greater than the charging protection voltage of the energy storage device; if the judgment result is positive, then set the limit voltage Ulimit as equal to the charging protection voltage of the energy storage device; if the judgment result is negative, then set the limit voltage Ulimit as equal to the highest limit of load protection voltage;
[0118] Step B 3 : Determine according to the following formula (2) the expected DCDC converting unit output current Iexpect:
[0000]
Iexpect
=
Irated
·
Edcdc
U
lim
[0119] Where, Irated is the rated output power of the fuel cell, Edcdc is the efficiency of the DCDC converting unit;
[0120] Step B 4 : Inquire the test curves with different charging currents and charging capacities; according to the constant current charging curve that the system limit charging current corresponds to, obtain the corresponding charging capacity when charging to the limit voltage; according to that charging capacity, find the corresponding voltage value on the constant current charging curve that the expected DCDC converting unit output current Iexpect corresponds to, the said corresponding voltage value is the first voltage setting of energy storage device Umax, as shown in FIG. 8 ; in which, the technical people in this field understand that the test curves with different charging currents and charging capacities (AH) can be obtained from the manufacturer.
[0121] Step B 5 : According to the energy recovery working condition in which the system uses the time limit, conduct actual testing by using the system controlled by the first voltage setting of energy storage device Umax, correct the first voltage setting of energy storage device Umax so that the actually measured highest voltage is slightly lower than the limit voltage Ulim;
[0122] Step B 6 : Correct the capacity of the energy storage device, specifically, according to the relational curve between the charging capacity/rated capacity and cycle times of energy storage device, or the relational curve between the discharging capacity/rated capacity and cycle times thereof, inquire the charging capacity/rated capacity ratio after multiple cycles, and then take the product of the first voltage setting of energy storage device Umax and charging capacity/rated capacity ratio as corrected first voltage setting of energy storage device Umax, for example, as shown in FIG. 9 .
[0123] Where, as a high current flows past, cable, contactor, cable connection, etc. may cause a voltage drop, which must be corrected. According to the energy recovery working condition in which the system uses time limit, conduct actual testing by using the system controlled by the first voltage setting of energy storage device Umax.
[0124] If the actually measured highest voltage is higher than the limit voltage, then a correction must be made.
[0125] If the actually measured highest voltage is much lower than the limit voltage, then a correction can also be made.
[0126] The correcting formula is:
[0000] Modified first voltage setting of energy storage device U max=the first voltage setting of energy storage device U max*before correction (limit voltage−the first voltage setting of energy storage device U max before correction)/(actually measured highest voltage−the first voltage setting of energy storage device U max).
[0127] By using the approximation method, gradually change the first voltage setting of energy storage device Umax to conduct testing, after measurement, the corrected first voltage setting of energy storage device Umax is obtained.
[0128] As shown in FIG. 10 , according to the relational curve between the charging capacity/rated capacity and cycle times of the energy storage device (that curve is provided by the supplier), inquire the charging capacity/rated capacity ratio after multiple cycles. As the discharging capacity is proportionate to the charging capacity, the relational curve between discharging capacity/rated capacity and cycle times can be used for replacement.
[0000] The corrected first voltage setting of energy storage device U max=the charging capacity/rated capacity of the corrected first voltage setting of energy storage device U max*obtained in Step B6.
[0129] What the system uses is the charging capacity/rated capacity after the energy storage device makes 1000 times of rated cycles.
[0130] Through that step, the influence of reduction in battery capacity on the system is pre-corrected, as a result, it is ensured that it is not necessary to correct in long system service the control parameters (the first voltage setting of energy storage device Umax). But the existing system with a SOC calculation mode has to estimate regularly the actual energy storage device capacity, reset the BC (energy storage device capacity) value in the system to improve the accuracy of SOC calculation.
[0131] C. The steps to determine the first current setting of DCDC Isetmin are shown below:
[0132] Step C 1 : Determine the lowest consumption current of the auxiliary system Is, specifically, use the obtained system controlled by the first voltage setting of energy storage device Umax to make the system be in an idle condition, after the system becomes stable, the consumption of the auxiliary system reduces to the minimum value, measure the current of the auxiliary system at this time, which is the lowest consumption current; where the lowest consumption current of the auxiliary system means the current consumed by the auxiliary system to maintain the minimum output of the auxiliary system and at which the fuel cell can be maintained to work.
[0133] Step C 2 : take the product of the lowest consumption current of the auxiliary system and coefficient K as the first current setting of DCDC Isetmin, where coefficient K is less than 1.
[0134] Preferably, coefficient K is 0.6, the reason is that the following factors have to be considered in actual setup:
[0135] a. The coefficient is to be several times higher than the measurement accuracy of the DCDC current measurement device.
[0136] b. The problem of drifting of the current sensor in long-term operation is to be considered, that the measurement value of the current sensor is higher than the actual current will not influence system operation; that the measurement value of the current sensor is lower than the actual current will influence system operation.
[0137] By considering the above factors comprehensively, in the preferable cases, coefficient K=0.6. That method need not rely too much on the accuracy, zero point, reaction speed, etc. of the sensor.
[0138] D. The steps to determine the maximum current setting that DCDC allows to output Imax are shown below:
[0139] Step D 1 : Determine according to the following formula (3) the maximum current setting that DCDC allows to output Imax:
[0000]
I
max
=
Irated
·
Edcdc
U
max
[0140] E. The steps to determine the second voltage setting of energy storage device Umin are shown below:
[0141] Step E 1 : Determine according to the following formula (4) the minimum charge capacity Cmin:
[0000] C min= C −( Is−I set min )· T
[0142] Where C is charging capacity, Is is the minimum consumption current of the auxiliary system, T is time, the said charging capacity is on the charging capacity and charging voltage curve of constant current charging with the maximum current setting that DCDC allows to output Imax as the current, find that the charging capacity that the first voltage setting of energy storage device Umax corresponds to for the charging voltage, the said time is set according to the response speed required by the system;
[0143] Step E 2 : According to the minimum charge capacity Cmin, find the charging voltage that the minimum charge capacity Cmin corresponds to on the charging capacity and charging voltage curve of constant current charging with the maximum current setting that DCDC allows to output Imax as the current, select that charging voltage as the second voltage setting of energy storage device Umin.
[0144] Further, determine through the following method the permissible DCDC current deviation value Ipermissible:
[0000] DCDC current deviation value=the DCDC converting unit output current controlled by system controller−the actual output current of DCDC converting unit.
[0145] Factors to be considered in actual setup:
[0146] a. The coefficient is to be several times higher than the measurement accuracy of DCDC current measurement device.
[0147] b. The problem of drifting of the current sensor in long-term operation is to be considered, that the measurement value of the current sensor is higher than the actual current will not influence system operation; that the measurement value of the current sensor is lower than the actual current will influence system operation.
[0148] Therefore, that value is preferably set as 5 A in this embodiment example.
[0149] Next, the specific applications of the said fuel cell mixed power supply energy management method is described through 4 different types of working conditions:
[0150] When the fuel cell power is used in vehicle work through the system that DCDC converting unit output is mixed with the energy storage device (the system as shown in FIG. 1 ):
[0151] Working condition 1: When the connected load (vehicle) operates at certain conditions (such as high power, startup), the required system current is higher than the DCDC converting unit current output, the insufficient current part is obtained from the energy storage device, at this time, the energy storage device voltage will inevitably decrease gradually. To avoid that the energy storage device voltage is lower than the minimum working voltage of the energy storage device resulting in the system being unable to operate, when the energy storage device voltage is lower than a certain value (the second voltage setting of energy storage device Umin), the system controller gradually increases the DCDC converting unit output current to make the energy storage device output current reduce gradually and the energy storage device voltage increase gradually. When operating at a high power continuously, the DCDC converting unit output current will increase until reaching the maximum current setting that DCDC allows to output.
[0152] Thus, through changing the output current of the DCDC converter, the effective and rational distribution of the energy required by the system is accomplished between the fuel cell and energy storage device.
[0153] Working condition 2: When the operating condition is changed so that the connected load (vehicle) operates at certain conditions (such as low power operation, idle speed), the required system current is less than the current output of DCDC converting unit, the DCDC converting unit charges the energy storage device, at this time, energy storage device voltage will inevitably increase gradually. To avoid that the energy storage device voltage exceeds the charging protection voltage of the energy storage device resulting in system stopping operation, when the energy storage device voltage reaches the set value (the first voltage setting of energy storage device Umax), the system controller gradually reduced the DCDC converting unit output current to make the energy storage device output voltage reduce gradually; when the energy storage device voltage is lower than the set value (the first voltage setting of energy storage device Umax), the DCDC converting unit output current will no longer change. At this time, that DCDC converting unit output current may still be higher than the system current that the system requires to maintain operation at a low power or idle speed, then the system repeats the above step; until the DCDC converting unit output current is less than the system current, the insufficient current part is obtained from the energy storage device, at this time, enter again into the case of above working condition 1.
[0154] Thus, through changing the output current of the DCDC converter, the replenishment of the electric quantity lost by the energy storage device is accomplished.
[0155] Working condition 3: When the connected load (vehicle) changes suddenly in some condition (from operation at a high power to operation at a low operation), the required system current reduces, the DCDC converting unit output current also reduces with it, at this time, the DCDC converting unit output current controlled by the system controller is higher than the actual output current of the DCDC converting unit. When the DCDC current deviation value is greater than or equal to the permissible DCDC current deviation value, the system controller controls to reduce at a fastest speed the DCDC converting unit output current until that output current is the first current setting of DCDC Isetmin, what that first current setting of DCDC Isetmin is less than the minimum power consumption of the system auxiliary components, current is obtained from system; at this time, the system control jumps to the case of above working condition 1. When the DCDC current deviation value is less than the permissible DCDC current deviation value, at this time, the system control enters into the case of above working condition 2.
[0156] The purpose to set up working condition 3: When a vehicle operates practically, it may change back to operation at a high power after turning from operation at a high power to operation at low power, the system may suddenly output a high current again; at this time, if working condition 3 is not set up to reduce the DCDC converting unit output current controlled by the system controller, then when the system outputs a high current suddenly, as the DCDC converting unit output current controlled by the system controller is higher than the actual output current of the DCDC converting unit, power may be obtained first from the DCDC converting unit, resulting in an impact on the fuel cell.
[0157] In this way, by setting the output current of the DCDC converter, the distribution strategy at the time when the system adds load suddenly is ensured: the energy storage device outputs first, the fuel cell follows.
[0158] Working condition 4: When a vehicle brakes, the vehicle with an energy feedback function will turn the energy resulting from braking into electric energy and feed it back to the power supply system; for a fuel cell system, such a condition is external current input into it, that current is input into the energy storage device, at the same time, the current outputted by the DCDC converting unit is also input into the energy storage device, this may make the energy storage device voltage increase sharply to the protection voltage and trigger shutdown, as a result, the energy resulting from braking can not be recovered to lead to the vehicle being out of control; therefore, when braking, it is necessary to control and reduce the current outputted by the DCDC converting unit first. To avoid that the energy storage device voltage exceeds the protection voltage of the energy storage device, when the energy storage device voltage reaches the set value (the first voltage setting of energy storage device Umax), the system controller controls to reduce gradually the DCDC converting unit output current, until that output current is the current setting of DCDC 1 . When that value is less than the minimum power consumption of the system auxiliary components, current is obtained from the system.
[0159] After braking is over, the system controls to jump to the case of working condition 1.
[0160] The reason that a compact structure as shown in FIG. 1 can be designed for the said forklift fuel cell supply system is mainly due to adopting the compact type fuel cell supply system as shown in FIG. 2 .
[0161] FIG. 2 is the schematic diagram of the structure of the compact type fuel cell supply system of the first embodiment example provided according to this invention, in this embodiment example, the said compact type fuel cell supply system consists of fuel cell 1 , DCDC converting unit 2 , contactor 3 , energy storage device 4 , power supply output end 5 , operation control unit 6 , controller 7 , auxiliary system 8 , in which the said contactor 3 is a normal open type high-current contactor, the said DCDC converting unit 2 includes DCDC converter 21 and high-power diode 22 connecting with it.
[0162] Specifically, the output end of the said fuel cell 1 connects the input end of the said DCDC converting unit 2 , DCDC converting unit 2 connects through the said contactor 3 the said energy storage device 4 , the output end of the said DCDC converting unit 2 also connects the said power supply output end 5 and the high-power auxiliary component 80 that the said auxiliary system 8 contains, the port of the said energy storage device 4 connects through the said contactor 3 the said power supply output end 5 and auxiliary system 8 , the said operation control unit 6 connects respectively the said energy storage device 4 , DCDC converting unit 2 , controller 7 , the said controller 7 connects respectively the said fuel cell 1 , DCDC converting unit 2 , the control end of contactor 3 , energy storage device 4 and auxiliary system 8 .
[0163] In this embodiment example, the positive pole of the output end of the said DCDC converting unit 2 connects through the said contactor 3 the positive pole of the said energy storage device 4 , the negative pole of the output end of the said DCDC converting unit 2 connects through the said contactor 3 the negative pole of the said energy storage device 4 , the positive pole of the said energy storage device 4 connects through the said contactor 3 the positive pole of the said power supply output end 5 and the positive pole of auxiliary system 8 , the negative pole of the said energy storage device 4 connects directly the negative pole of the said power supply output end 5 and the negative pole of auxiliary system 8 ; and in a variation of this embodiment example, the difference from the first embodiment example as shown in FIG. 1 is that in this variation, the change of the said contactor 3 in connecting position is: the said contactor 3 is connected between the negative pole of the output end of the said DCDC converting unit 2 and the negative pole of the said energy storage device 4 , and the positive pole of the output end of the said DCDC converting unit 2 and the positive pole of the said energy storage device 4 are connected directly between them, correspondingly, the positive pole of the said energy storage device 4 connects directly the positive pole of the said power supply output end 5 and the positive pole of auxiliary system 8 , the negative pole of the said energy storage device 4 connects through the said contactor 3 the negative pole of the said power supply output end 5 and the negative pole of auxiliary system 8 . The technical people in this field understand that the two connection modes for contactor 3 as described in this natural paragraph can both realize “DCDC converting unit 2 connecting through the said contactor 3 the said energy storage device 4 ” and “the port of the said energy storage device 4 connecting through the said contactor 3 the said power supply output end 5 and auxiliary system 8 ”.
[0164] The said auxiliary system 8 consists of air supply system, cooling system, hydrogen system, hydrogen safety system, the said high-power auxiliary component 80 refers to a high-power component in the auxiliary system (for example, fan, pump, heat dissipation fan). The technical people in this field can refer to the existing technology to accomplish the said auxiliary system 8 and its high-power auxiliary component 80 . No unnecessary detail is to be given here.
[0165] The said operation control unit 6 is used to receive operation signals and supplies power for the said controller 7 and DCDC converting unit 2 , the said controller 7 is used to receive the operation instructions generated by the said operation control unit 6 according to the said operation signals and control according to the said operation instructions the said contactor 3 , DCDC converting unit 2 , auxiliary system 8 , the said controller 7 is also used to measure the state parameters of the said fuel cell 1 , measure the state parameters of the said energy storage device 4 , measure the state parameters of the said auxiliary system 8 and receive the state data of the said DCDC converting unit 2 . The said DCDC converter 21 consists of CAN communication module, input voltage measurement module, input current measurement module, output voltage measurement module, output current measurement module. Preferably, DCDC converter 21 can control according to the communication data of the CAN communication module the specific numerical values of the output current, voltage; also outputs through the CAN communication module such data as input voltage, input current, output voltage, output current, etc. The state data of the said DCDC converting unit 2 includes DCDC input current, DCDC input voltage.
[0166] The said controller 7 is a controller with an integrated design, which is equivalent to the scattered fuel cell controller, whole vehicle controller, battery energy management system in the invention patent application of China with patent application number “200610011555.1”; further specifically, the said controller 7 can consist of energy management unit, fuel cell control unit, energy storage device monitoring unit, hydrogen safety monitoring unit, system failure monitoring unit and startup control unit.
[0167] More specifically, as shown in FIG. 2 , the output end of the said fuel cell 1 connects the input end of the said DCDC converter 21 , the positive pole of the output end of the said DCDC converter 21 connects the positive pole of the said high-power diode 22 , negative pole of the said high-power diode 22 connects through the said contactor 3 the said energy storage device 4 , the said DCDC converter 21 connects the said controller 7 and is controlled by the said controller 7 , the said DCDC converter 21 connects the said operation control unit 6 and receives the power supplied by the said operation control unit 6 . And in a variation of this embodiment example, the difference from the first embodiment example as shown in FIG. 2 is that in this variation, the positive pole of the output end of the said fuel cell 1 connects the positive pole of the said high-power diode 22 , the negative pole of the said high-power diode 22 connects the positive pole of the input end of the said DCDC converter 21 , the negative pole of the output end of the said fuel cell 1 connects directly the negative pole of the input end of the said DCDC converter 21 , the output end of the said DCDC converter 21 directly connects through the said contactor 3 the said energy storage device 4 .
[0168] Further, in this embodiment example, the said compact type fuel cell supply system also consists of monitoring display 91 , ON and OFF button 92 , remote control 93 , emergency stop button 94 , in which the said monitoring display 91 connects the said controller 7 , the said ON and OFF button 92 connects respectively the said operation control unit 6 and controller 7 , the said remote control 93 connects in a radio mode the said operation control unit 6 , the said emergency stop button 94 connects the said operation control unit 6 . As shown in FIG. 1 , when the said ON and OFF button 92 or remote control 93 gives a startup signal, the said operation control unit 6 supplies power to the said controller 7 , the said controller 7 outputs a control signal to the contactor used as a switch to make it close, the said energy storage device 4 supplies power through the said contactor 3 to the said high-power auxiliary component 80 , in the said auxiliary system 8 , except the said high-power auxiliary component 80 , other devices (for example, hydrogen system, hydrogen safety system) are supplied by the said controller 7 , at the same time, the said controller 7 outputs signals to all modules constituting the said auxiliary system 8 to start the said fuel cell 1 ; after starting, the said contactor 3 maintains the state of connection at all times. By adopting this starting mode, it is not necessary to use additionally configured auxiliary battery and auxiliary DC/DC converter for charging, as a result, parts and components and corresponding lines are reduced, system reliability is improved, space is saved, system volume and costs are reduced.
[0169] In a preferable case of this embodiment example, as shown in FIG. 3 , the said high-power diode 22 is placed on the heat dissipation passage of the said DCDC converter 21 , this can use the air discharged from the air duct 2101 by the heat dissipation fan 2102 contained by the said DCDC converter itself to dissipate heat from the said high-power diode 22 , as a result, the heat dissipation fan on the heat dissipater 2201 (i.e. aluminum fin) for the said high-power diode is saved, the volume of heat dissipater is reduced, energy is saved, at the same time, the line to supply power to that heat dissipation fan is also saved. The said operation control unit 6 changes the electric connection state with the said DCDC converting unit and controller 7 according to the startup operation signal received. Thus, the said controller 7 is in an operation condition only when the system is working and will not lead to the problem of high system energy consumption due to being always in an operation condition.
[0170] Next, the system working principle is described through a preferable embodiment of this invention. Specifically, When the system is not started, the said operation control unit 6 and the said controller 7 , DCDC converting unit 2 establish no electric connection state between them. When the button of the said remote control 93 or the said ON and OFF button 92 is depressed, the said operation control unit 6 and the said controller 7 , DCDC converting unit 2 establish an electric connection between them, the said energy storage device 4 supplies power through the said operation control unit 6 to the said controller 7 , the output signal of the said controller 7 drives the said contactor 3 to get connected, the said energy storage device 4 supplies power through the said contactor 3 to the said high-power auxiliary component 80 , in the said auxiliary system 8 , except the said high-power auxiliary component 80 , other devices (for example, hydrogen system, hydrogen safety system) are supplied by the said controller 7 , at the same time, the said controller 7 outputs working signals to all modules constituting the said auxiliary system 8 to start the said fuel cell 1 ; the said fuel cell 1 outputs power to the said DCDC converting unit 2 , the said controller 7 controls according to the received state data signals of the said fuel cell 1 , energy storage device 4 , DCDC converting unit 2 the said DCDC converting unit 2 output current; under the normal system working condition, the output voltage of the said DCDC converting unit 2 is higher than the output voltage of the said energy storage device 4 , the output current of the said DCDC converting unit 2 is output through the said power supply output end 5 to the small vehicle drive system carrying the said fuel cell supply system to drive the small vehicle to work, at the same time, the said DCDC converting unit 2 charges the said energy storage device 4 , supplies power to the said high-power auxiliary component 80 , operation control unit 6 ; when a small vehicle is in a high-power driving condition, the said power supply output end 5 needs to output high power, high currency, at this time, the said DCDC converting unit 2 output current is not sufficient to satisfy the requirements, the said energy storage device 4 will output current together with the said DCDC converting unit 2 to the small vehicle driving system carrying that fuel cell supply system through the said power supply output end 5 to drive that small vehicle to maintain the high-power driving condition; when the small vehicle is in a braking condition, the power energy recovered by the brake charges through the power supply output end the energy storage device.
[0171] When it is necessary to start the system, just depress the button of the said remote control 93 or the said ON and OFF button 92 , in the meantime that the said operation control unit 6 and the said controller 7 , DCDC converting unit 2 establish an electric connection, the said operation control unit 6 outputs a switch signal to the said controller 7 , the said controller 7 , after receiving the switch signal, outputs a signal to maintain power supply to the said operation control unit 6 , so that the said operation control unit 6 and the said controller 7 , DCDC converting unit 2 maintain an electric connection state; at the same time, the said controller 7 also drives the indicator light of the said ON and OFF button 92 to become on to prompt system starting; at this time, the button of the said remote control 93 or the said ON and OFF button 92 can be released.
[0172] When it is necessary to close the system, depress again the button of the said remote control 93 or the said ON and OFF button 92 , the said operation control unit 6 outputs a switch signal to the said controller 7 , the said controller 7 , after receiving the switch signal, controls the indicator light of the said ON and OFF button 92 to blink (prompting switching off, at this time, the button of the said remote control 93 or the said ON and OFF button 92 can be released), the said controller 7 simultaneously controls the said auxiliary system 8 to stop working, and then stops outputting the signal to maintain power supply to the said operation control unit 6 , so that the electric connection of the said operation control unit 7 and the said controller 7 , DCDC converting unit 2 is disconnected; the whole system stops working.
[0173] When the said emergency stop button 94 is depressed, the electric connection between the said operation control unit 6 and the said controller 7 , DCDC converting unit 2 get disconnected quickly to cut off the power supply to the whole system and make the system stop working.
[0174] The said monitoring display 91 gets power, communication data from the said controller 7 , displays the system condition, failure information, etc. on the screen.
[0175] The embodiment examples of this invention are described above. What needs understanding is that that this invention is not limited to above specific embodiments. The technical people in this field can make various variations or modifications with the Claim, and this does not influence the essential contents of this invention.
|
This invention provides a kind of mixed power supply energy management method for fuel battery, including the following steps: initialization; control the output current of DCDC converting unit according to the measured energy storage device voltage and the actual current outputted by the DCDC converting unit, respond to the energy need resulting from load condition change and at the same time ensure the energy storage device to be in a best charge state; send a current setting instruction to the DCDC converting unit. This invention does not adopt the SOC calculation mode any more, the system no longer relies on the accuracy, reliability of current sensor; and this invention is strongly compatible, highly reliable, strongly practical and stable in output voltage, with the same system being applicable to more vehicles of different models (forklift) and parameter correction being unnecessary. By correcting battery capacity decrease in advance through setting up parameters in advance, the long-term reliability of the system is ensured.
| 8
|
TECHNICAL FIELD
[0001] The invention relates to a heat protection assembly for a charging installation of a metallurgical reactor. It further relates to a charging installation of a metallurgical reactor.
BACKGROUND ART
[0002] Metallurgical reactors are well-known in the art. These reactors are typically gravity-fed from above by a charging installation, which in turn may be fed with bulk material from intermediate hoppers. One type of charging installation is disclosed in international application WO 2012/016902 A1. Here, the material is fed through a feeder spout, which is positioned above the inlet of a distribution chute. The chute is mounted on a rotatable tubular support, in which the feeder spout is disposed. To provide for a two-dimensional mobility of the chute, it is also tiltable relative to the support by shafts connected to a gear assembly. The gear assembly is positioned inside a gearbox formed by the support and a stationary casing on which the support is rotationally mounted. For protection of the gear assembly, the bottom portion of the casing has a heat protection shield with a cooling circuit. The shield defines a central opening in which a lower portion of the support is disposed. Since the heat protection shield may be subjected to relatively high temperatures and considerable temperature changes, while there may be also high temperature gradients, there may be a need for inspection, maintenance and/or replacement of the shield or at least of parts thereof. This in particular refers to the cooling circuit, but also to a heat protection layer of refractory material, which is disposed on the underside of the cooling circuit. While a charging installation of the abovementioned application generally works well, maintenance of the heat protection shield is often complicated and time-consuming. Repair of a damaged refractory layer can only be performed by guniting or shot screening when the reactor is shut down. A platform needs to be introduced into the upper part of the reactor. This makes the work not only tedious, but also dangerous.
BRIEF SUMMARY
[0003] The disclosure seeks to increase the lifetime of a heat protection shield in a charging installation of a metallurgical reactor. This is accomplished by a heat protection assembly as described herein.
[0004] A heat protection assembly for a charging installation of a metallurgical reactor is provided herein. The metallurgical reactor may in particular be of the blast furnace type. A charging installation will generally be of the type where the bulk material is gravity-fed to the reactor. Therefore, in these cases, the charging installation is—at least for the larger part—intended to be installed above the reactor. The heat protection assembly will usually be configured to protect a reactor side surface of the charging installation, i.e. in the above-mentioned case, the bottom surface. The assembly comprises a plurality of heat protection tiles disposed adjacent to each other along a surface and also comprises a plurality of heat protection panels. The surface along which the tiles are disposed may be plane, bent or other. The term “surface” herein is to be understood in a geometrical way, i.e. it does not necessarily have to be the physical surface of a device. Each tile is heat-protective in that it is heat-resistant, in particular fire-resistant, and has by its geometry some shielding capacity. Each tile normally comprises a refractory material. Heat resistance may be desired up to about 1200° C. as such temperatures may be reached in case of an incident.
[0005] A gap may be provided between adjacent tiles. The gap allows for a thermal expansion of the individual tiles. The thermal stress within an individual tile is therefore relatively small compared to the stress in a monolithic refractory layer. The size of the gap may be chosen according to the expected thermal expansion of the tiles under the operating conditions of the charging installation. The tiles may be allowed to touch each other when the top temperatures of the installation are reached, since the thermal stress in such a case is still less than with a monolithic structure. On the other hand, the size of the gap at room temperature can be chosen so that it will not close even at top temperatures. However, the size of the gap should not be too great, since this could negatively affect the shielding properties of the heat protection assembly. It is possible that the tiles overlap, e.g. like a tongue and groove, so that an expansion of the tiles is possible while heat convection through the gap is hindered. It is also within the scope of the invention that some material is placed within the gap as long as this material does not hinder the thermal expansion of the individual tiles too much. For example, the material may be highly compressible.
[0006] According to a preferred embodiment, the tiles comprise a support structure on which a refractory material is disposed. Such as support structure forms a kind of “backbone” of the tile. Normally, the support structure will be made of material that is highly resistant to thermal expansion and contraction processes, i.e. the material is very unlikely to form cracks under these processes. It goes without saying that the material should have a melting point that is considerably higher than the expected temperatures during operation of the charging installation. Possible materials are ceramic or metals, for example steel. The refractory material, which is disposed on the support structure, of course has to be highly heat resistant and flame resistant. Preferably, it is a poor heat conductor. The latter property is not so crucial for the support structure. On the other hand, the refractory material does not have to be as resistant to thermal deformation processes, because even if small cracks form in the refractory material, it may still be held in place by the connection to the support structure.
[0007] It is preferred that the refractory material can be cast onto or around the support structure. I.e., the refractory material should be applicable in a liquid or semi-liquid form, which solidifies after application to the support structure. One such material which is preferred is refractory concrete.
[0008] This also opens the possibility of forming the gap by placing a kind of “spacer” material in the position of the intended gap before casting the refractory material. The spacer material may be removed after the casting process before the tile is installed to the charging installation. Alternatively, the gap may be filled with a material which is volatile under the operating temperatures of the metallurgical reactor. I.e. the spacer material is volatile and can be left in place during installation of the tile. “Volatile” in this context refers to materials that will melt and/or evaporate as well as materials which disappear due to a chemical reaction at high temperatures, usually due to combustion. Of course, since the only function of the material is to provide a kind of “die” for the casting process of the refractory material and the spacer material is lost during operation of the reactor, cheap materials are preferred for this purpose. For example, wood-based or paper materials can be used. A particularly preferred material is cardboard.
[0009] Preferably, the support structure comprises a mesh on which the refractory material is disposed. The mesh structure, which may be essentially two-dimensional or three-dimensional, helps to cover a large space with relatively little material. Depending on the material used for the support structure, this may help to keep the weight and/or the cost of the tile low. Also, since the heat conductivity of the support structure is often higher than that of the refractory material, it is desirable to use as little support structure as possible.
[0010] There are a multitude of different mesh configurations which may be used. Some may be essentially two-dimensional, like wire mesh. Especially when the thickness of the tile is greater, three-dimensional structures will be preferred. According to one preferred embodiment, the mesh is hexagonal. The hexagonal structure is preferably disposed along the plane of the tile, so that the support structure resembles a honeycomb.
[0011] The heat protection assembly comprises a plurality of heat protection panels, each panel comprising a common base plate to which a plurality of tiles are connected, which heat protection panels are configured to be mounted on the charging installation adjacent to each other. The connection of the tiles to the base plate may be a detachable or permanent one. The same materials which can be used for the support structure may also be used for the base plate. In fact, it is even conceivable that the base plate and the support structures are formed as one piece. In a subsequent casting process, the refractory material can be applied to the support structures. It is preferred that the heat protection panels are configured to be detachably mounted on the charging installation.
[0012] In this context it is herein provided a heat protection assembly for a charging installation of a metallurgical reactor, which assembly comprises a plurality of heat protection panels, which heat protection panels are configured to be mounted on the charging installation adjacent to each other, wherein each panel at least comprises a heat protection layer. The layer may be disposed on a base plate and may further comprise a plurality of tiles, which are connected to the base plate. By such a heat protection assembly, the installation and maintenance of a heat protection shield in a charging installation is facilitated.
[0013] In a preferred embodiment, the panel comprises spacer members, which define a space separating the tiles from the base plate. The space mainly serves two purposes. On the one hand, the thermal contact between the tiles and the base plate is reduced. On the other hand, such a gap also allows for thermal expansion perpendicular to the surface along which the tiles are disposed. The spacer members normally are disposed on the side of the tile which faces the base plate and extend perpendicular to the above-mentioned surface.
[0014] While the space separating the tiles from the base plate could be just filled with air, it is preferred that a heat insulation layer is disposed between the base plate and the tiles. Such an heat insulation layer generally reduces the heat conduction of the assembly and in particular reduces convection flow via the gaps between the tiles. A variety of materials, which are known in the art, can be used for the heat insulation layer. It is particularly preferred to use at ceramic fiber material.
[0015] In nearly any case, the elements of the charging installation which are protected by the heat protection assembly also require some cooling circuit. According to preferred in embodiment, parts of such cooling circuit can be installed on the heat protection panel. In this case, each heat protection panel comprises at least one coolant channel. Such a coolant channel can be provided by a conventional pipe and/or by a channel which is provided within the base plate. In the described embodiment, the heat protection and the cooling system are both designed in a modular way, which allows very easy mounting and dismounting of individual panels for inspection, repair or replacement. It should also be noted that such inspection, maintenance and/or replacement may be carried out from inside the charging installation.
[0016] A heat protection panel is further provided for a charging installation of a metallurgical reactor, with a plurality of heat protection tiles disposed adjacent to each other along a surface and connected to a common base plate, wherein a gap is provided between adjacent tiles. These elements have been described above with respect to the inventive heat protection assembly. Preferred embodiments of the heat protection panel correspond to those of the heat protection assembly.
[0017] Moreover, a charging installation of a metallurgical reactor is provided, with a heat protection assembly, which comprises a plurality of heat protection tiles disposed adjacent to each other along a surface, wherein a gap is provided between adjacent tiles. It is understood that the surface is normally on a reactor side of the charging installation, i.e. a side which faces the reactor.
[0018] Preferred embodiments of the charging installation correspond to the embodiments of the heat protection assembly as described above.
[0019] The charging installation may in particular comprise a casing for a gear assembly. Here, the heat protection assembly is configured to protect an annular bottom surface of the casing. Of course in this case, the bottom surface of the casing is facing the reactor. Such a configuration is also disclosed in WO 2012/016902 A1, which is hereby included by reference. Here, a conventional heat shield is employed, though. The gear assembly is part of a tilting mechanism for a distribution chute of the charging installation. The casing may also be considered as a gearbox, since it forms a housing for the gear assembly. However, the gear assembly is able to rotate within the housing.
[0020] It is highly preferred that the heat protection panels are mountable and dismountable from inside the casing. Since the casing usually has an access door for maintenance of the gear assembly or the like, the inside is easily accessible. If connection means like bolts are accessible from the inside, mounting or dismounting of the panels can be performed easily and safely.
[0021] If the heat protection assembly comprises a plurality of heat protection panels as described above, the panels are usually too heavy to be handled manually. Therefore, some kind of hoist needs to be applied. While it is possible to introduce such a device into the casing for each maintenance operation and take it out again afterwards, it is preferred that a hoist device for handling the panels is disposed (or mounted) inside the casing. One example for such a hoist device is a gantry crane. In an annular casing as the one shown in WO 2012/016902 A1, the gantry crane may comprise an annular beam disposed near the top of the casing. It may thus be placed above any section of the casing to lift any panel located on the bottom.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Details of the invention will now be described with reference to the drawings, wherein
[0023] FIG. 1 is perspective cut-away view of a first embodiment of the heat protection panel; and
[0024] FIG. 2 is a perspective cut-away but of a second embodiment of the heat protection panel.
[0025] FIG. 3 is a perspective cutaway view of a charging installation in which the heat protection panel of FIG. 1 is used.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] FIG. 1 shows a cut-away view of a heat protection panel 10 , which is used for protecting a reactor-side bottom section of a charging installation of a metallurgical reactor. The bottom section to be protected could, for instance, belong to the housing for a gear assembly of a distribution device as described in WO 2012/016902 A1. This bottom section is annular; therefore it can be covered by arc-shaped panels 10 . The shape of the panel 10 is largely determined by the base plate 11 , which is made of steel. A meandering coolant channel 12 is disposed in the base plate 11 and is covered by a cover plate 13 , which is welded to the base plate 11 . The cover plate 13 may have a meandering structure following the meandering structure of the coolant channel 12 . If there is a deformation of the base plate 11 , there is a movement in the coolant channel 12 . With a cover plate 13 closely replicating the shape of the coolant channel 12 , it is possible to reduce the risk of the weld between the cover plate 13 and the base plate 11 breaking, as the cover plate 13 will follow the movement of the coolant channel 12 . A supply pipe 14 and a drainpipe 15 are connected to the channel 12 and can be used for connection to a coolant supply. The base plate 11 carries a plurality of heat protection tiles 31 . 1 , 31 . 2 , 31 . 3 , 31 . 4 , which form a heat protection layer 30 . Each of the heat protection tiles 31 is connected to the base plate 11 via knob-like spacer members 34 is, which are disposed on a mounting strip 33 . A hexagonal mesh 35 is connected to the mounting strip 33 . The mesh 35 serves as a backbone of the heat protection tiles 31 and provides for structural integrity. The heat protection properties of the tile 31 mainly result from a block of refractory concrete 36 which is cast around the mesh 35 . The tiles 31 . 1 , 31 . 2 , 31 . 3 , 31 . 4 do not touch each other, but are provided with the gap 37 in between. This gap 37 allows for thermal expansion during operation of the heat protection layer 30 .
[0027] In the production process the mounting strip 33 with the mesh 35 is mounted to the base plate 11 before the refractory concrete 36 is applied. A strip of cardboard 38 is placed between the individual tiles 31 . 1 , 31 . 2 , 31 . 3 , 31 . 4 to prevent concrete 36 from entering the gap 37 . The refractory concrete 36 is then cast around the mesh 35 . The cardboard 38 could be removed prior to installation of the panel 10 , but this is not necessary. The cardboard 38 will quickly burn away under the operating conditions of the panel 10 and thus can be left within the gap 37 , as shown in FIG. 1 . The spacer members 34 provide for a space between the tile and the base plate 11 , which space is filled with the heat insulation layer 32 composed of ceramic fibers. The heat protection panel 10 therefore is a module which combines three functional layers: the heat protection layer 30 with tiles 31 . 1 , 31 . 2 , 31 . 3 , 31 . 4 protects against extreme temperatures and also provides thermal insulation, the insulation layer 32 further enhances the insulation effect, while the coolant channel 12 with the pipes 14 , 15 provides for active cooling. The panel 10 is provided with side flanges 18 , which extend perpendicular to the plane of the base plate 11 . These side flanges 18 are provided with a plurality of through-holes 19 and are used to connect the panel 10 to neighboring panels and/or the charging installation. Three eyelets 21 are disposed on the upper side of the base plate 11 , which facilitate handling of the panel 10 and by a hoist 41 or the like.
[0028] FIG. 2 shows an alternative embodiment of an inventive panel 110 . In this case, a simple base plate 111 without any channel structures has been employed, while the heat protection layer 30 and the heat insulation layer 32 are identical to the embodiment shown in FIG. 1 . The panel 110 could be used in the case where no active cooling is necessary or it could be combined with a separate cooling system.
[0029] FIG. 3 shows a perspective cutaway view of a charging installation 1 , which features an annular shaped casing 2 for a gear assembly and a cylindrical support 3 for the gear assembly. The gear assembly, which is not shown here, is used for tilting of a distribution chute of the charging installation 1 . The support 3 is rotatably mounted with respect to the casing 2 . As can be seen from FIG. 3 , a plurality of heat protection panels 10 as shown in FIG. 1 are disposed next to each other along the annular bottom of the casing 2 . Bolts 20 , which are put through the holes 19 , are used to connect each side flange 18 to a radially disposed plate-like mounting member 5 of the casing 2 . At the same time, the bolts 20 serve to interconnect the individual panels 10 .
[0030] As can be seen in FIG. 3 , a beam 40 of a gantry crane 41 is connected to the top of the casing 2 . The beam 40 is annular-shaped and allows the crane 41 to be moved to virtually any position within the casing 2 . FIG. 3 illustrates the removal of a heat protection panel 10 , which is lifted by a chain 42 of the gantry crane 41 . FIG. 3 shows the chain connected to hoist rings 22 , which are not shown in FIGS. 1 . Alternatively, the chain 42 could be connected to the eyelets 21 . By moving the gentry crane 41 along the beam 40 , the heat protection panel 10 may be moved to an access door (not shown) of the casing 2 , from where it may be removed for repair or replacement. A replacement panel can be installed by a reverse sequence of operations. It is therefore apparent that a replacement of the heat protection panel 10 can be achieved in short time and easily. In particular, there is no need for personnel to work on the underside of the heat protection assembly 4 , i.e. near or within the reactor itself. The mounting and dismounting can be done from within the casing 2 . This makes the work not only easier but also significantly adds to the safety of the working personnel.
|
The invention relates to a heat protection assembly ( 2, 30 ) for a charging installation ( 1 ) of a metallurgical reactor. In order to increase the lifetime of a heat protection shield in a charging installation of a metallurgical reactor, the assembly ( 2, 30 ) comprises a plurality of heat protection tiles ( 31.1, 31.2, 31.3, 31.4 ) disposed adjacent to each other along a surface The assembly further comprises a plurality of heat protection panels ( 10, 110 ), each panel ( 10, 110 ) comprising a common base plate ( 11, 111 ) to which a plurality of tiles ( 31.1, 31.2, 31.3, 31.4 ) are connected, which heat protection panels ( 10, 110 ) are configured to be mounted on the charging installation ( 1 ) adjacent to each other.
| 5
|
BACKGROUND OF THE INVENTION
The invention relates to a twist lock attachment system for attaching a fixture, such as a lighting fixture, to a structural support such as a wiring conduit. The invention particularly applies to lighting fixtures having sheet metal housings.
Fixtures, for example commercial and industrial lighting fixtures, are often installed by hanging from a structural support such as a threaded conduit. A commercial or industrial lighting fixture that includes a ballast transformer can have a substantial weight, making the installation task difficult.
Thus, hanging a heavy, sheet metal housed lighting fixture from a conduit typically requires either extensive bracketry, or expensive permanently-attached threaded bushings. As an example of bracketry, some lighting fixture designs include a relatively small cast plate-like mounting bracket that threads onto the conduit. The heavier, main part of the lighting fixture then slides onto the mounting bracket plate. With permanently-attached bushings, an installer must twist a heavy lighting fixture onto a threaded conduit without damaging the threads or dropping the fixture.
In the case of lighting fixtures that have a die cast housing, in contrast to a sheet metal housing, a current practice is to include a twist lock bushing as part of the housing. Thus, integral hook-like tabs are cast into the housing, and cooperate with a separate locking ring that threads on to the conduit. Twist lock bushings are particularly convenient to use. Mating elements of a twist lock bushing assembly are engaged and then rotated relative to each other a relatively short angular distance, such as 90°, which is far simpler for an installer compared to the multiple rotations required to attach a conventional threaded bushing to a conduit. However, a die cast housing with an integral twist lock bushing element is more expensive than a sheet metal housing.
BRIEF SUMMARY OF THE INVENTION
It is therefore seen to be desirable to provide a twist lock attachment system suitable for use with a fixture, such as a lighting fixture, having a housing made of sheet metal.
In an exemplary embodiment, a twist lock attachment system includes, in general, a mounting plate made of sheet metal included as part of a fixture, as well as a twist lock bushing attachable to a structural support, such as a threaded conduit. The mounting plate has an exterior surface and an opposed interior surface separated by a mounting plate thickness, as well as a generally circular mounting aperture. The twist lock bushing includes a tubular body correspondingly generally circular in cross section, and having an insertion end and an opposite end. The mounting plate and the twist lock bushing releasably engage each other by relative movement to insert the tubular body into the mounting aperture with the mounting plate and the bushing angularly oriented in an insertion and removal position with reference to each other, and subsequent rotation of the mounting plate and the twist lock bushing relative to each other in a first rotational direction to an installed position.
The tubular body more particularly includes a radially-extending top flange located intermediate the opposite end and the insertion end. The top flange has a flange bearing surface axially facing the insertion end for limiting relative axial movement in an insertion direction by bearing against the exterior surface of the mounting plate. The flange bearing surface accordingly defines a flange bearing surface plane. The tubular body additionally includes at least two radially-extending locking tabs intermediate the top flange and the insertion end generally adjacent the insertion end. The locking tabs have locking tab bearing surfaces axially facing the opposite end for retaining the tubular body within the mounting aperture by bearing against the interior surface of the mounting plate in the installed position. Thus, the tab bearing surfaces are separated from the flange bearing surface plane a distance corresponding to the thickness of the mounting plate. For clearing the locking tabs as the tubular body is inserted into or removed from the mounted aperture in the insertion and removal position, the mounting plate has at least two locking tab clearance slots extending radially from the mounting aperture. Releasable elements are provided for preventing relative rotational movement of the mounting plate and the bushing in the installed position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view, partially broken away, of a fixture embodying the invention;
FIG. 2 is a top plan view of a mounting plate included as part of the fixture of FIG. 1;
FIG. 3 is a bottom plan view of the mounting plate;
FIG. 4 is a side elevational view of a twist lock bushing in isolation;
FIG. 5 is a top plan view of the bushing, taken on line 5 — 5 of FIG. 4;
FIG. 6 is a bottom plan view of the bushing, taken on line 6 — 6 of FIG. 4;
FIG. 7 is a side elevational view of the twist lock bushing in a different orientation compared to FIG. 4, taken on line 7 — 7 of FIG. 5;
FIG. 8 is an enlarged top plan view, showing the twist lock bushing and a portion of the mounting plate in the insertion and removal position;
FIG. 9 is an enlarged bottom plan view corresponding to FIG. 8, showing the twist lock bushing and a portion of the mounting plate in the insertion and removal position;
FIG. 10 is an enlarged top plan view, taken on line 10 — 10 of FIG. I, showing the twist lock bushing and a portion of the mounting plate in the installed position;
FIG. 11 is an enlarged bottom plan view, taken on line 11 — 11 of FIG. 1 and corresponding to FIG. 10, showing the twist lock bushing and a portion of the mounting plate in the installed position;
FIG. 12 is an installed-position cross-sectional view taken on line 12 — 12 of FIG. 10;
FIG. 13 is an installed-position cross-sectional view taken on line 13 — 13 of FIG. 10, with a set screw additionally included;
FIG. 14 is a view taken on line 14 — 14 of FIG. 10;
FIG. 15 is a view, in the same orientation of FIG. 1, taken on line 15 — 15 of FIG. 10;
FIG. 16 is a view taken on line 16 — 16 of FIG. 10; and
FIG. 17 is a view taken on line 17 — 17 of FIG. 8 .
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1, a representative lighting fixture 20 includes an upper housing 22 made generally of sheet metal, a lower housing 24 containing a relatively heavy ballast transformer, and a socket 26 for a high intensity discharge lamp (not shown). The fixture 20 typically has additional elements, not shown in FIG. 1, such as a reflector and a lens.
The upper housing 22 includes an upper mounting plate 28 made of sheet metal. The mounting plate 28 has an exterior surface 30 and an opposed interior surface 32 , separated by a mounting plate thickness. A suitable mounting plate thickness for a fixture weighing 23 pounds (10 kg) is 0.05 inch (1.27 mm). The upper housing 22 also has an end cover 34 , which is removable to provide wiring access, as well as an opposite end cover.
Also shown in FIG. 1 is a twist lock bushing 40 which is attachable to a structural support. In the example of FIG. 1, the structural support is a threaded electrical conduit 42 , shown in phantom. The threaded electrical conduit 42 may comprise the lower end of a hanger hook (not shown), which includes an aperture for electrical conductors. Twist lock bushings embodying the invention may be provided which are attachable to other forms of structural support, such as directly to beams, or to other ceiling structures, including electrical junction boxes.
The twist lock bushing 40 and the mounting plate 28 together comprise a twist lock attachment system 44 .
FIG. 2 is a top plan view of a portion of the mounting plate 28 (generally on line 10 — 10 of FIG. 1, but with the twist lock bushing 40 not installed). The exterior surface 30 is visible in FIG. 2 . The mounting plate 28 has a generally circular mounting aperture 46 , with at least two locking tab clearance slots 48 and 50 extending radially from the mounting aperture 46 . In the illustrated embodiment, there are a pair of diametrically-opposed locking tab clearance slots 48 and 50 .
FIG. 3 is a corresponding bottom plan view of the mounting plate 28 , with the opposed interior surface 32 visible, as well as the mounting aperture 46 , and the locking tab clearance slots 48 and 50 .
FIGS. 4, 5 , 6 and 7 show the twist lock bushing 40 in isolation. In particular, FIG. 4 is a side elevational view in the same orientation as FIG. 1; FIG. 5 is a top plan view taken on line 5 — 5 of FIG. 4; FIG. 6 is a bottom plan view taken on line 6 — 6 of FIG. 4; and FIG. 7 is another side elevational view, taken on line 7 — 7 of FIG. 5 . The twist lock bushing 40 has a tubular body 52 which is generally circular in cross-section. The tubular body 52 has an insertion end 54 and an opposite end 56 .
Referring to the cross-sectional views of FIGS. 12 and 13, in addition to FIGS. 4-7, the tubular body 52 has a tapered bore 58 , the interior surface of which is threaded for attachment to a conduit such as the FIG. 1 conduit 42 . The interior bore 58 terminates at its lower end in an aperture 60 through which electrical conductors (not shown) pass.
To facilitate threading on to the conduit 42 , the bushing 40 tubular body 52 additionally includes an integral hex nut structure 62 having surfaces 64 , 66 , 68 , 70 , 72 and 74 engageable by a wrench (not shown), in a conventional manner.
Intermediate the opposite end 56 and the insertion end 54 is a radially-extending top flange 78 . In the illustrated embodiment, the top flange 78 comprises a plurality of top flange segments, in particular a pair of top flange segments 80 and 82 separated by annular gaps 84 and 86 . The top flange 78 has a lower flange bearing surface 88 axially facing the insertion end 54 , and defining a flange bearing surface plane. The flange bearing surface 88 limits relative axial movement in an insertion direction by bearing against the exterior surface 30 of the mounting plate 28 . Opposite the flange bearing surface 88 is a flange upper surface 90 .
In addition, intermediate the top flange 78 and the insertion end 54 generally adjacent the insertion end 54 are at least two radially-extending locking tabs 92 and 94 . The locking tabs 92 and 94 have respective locking tab bearing surfaces 96 and 98 axially facing the opposite end 56 of the tubular body 52 . The locking tab bearing surfaces 96 and 98 retain the tubular body 52 within the mounting aperture 46 in the installed position by bearing against the interior surface 32 of the mounting plate 28 . The locking tab bearing surfaces 96 and 98 accordingly are spaced from the flange bearing surface plane defined by the lower flange bearing surface 88 a distance corresponding to the thickness of the sheet metal mounting plate 28 , including an allowance for parts tolerances. For use in combination with a mounting plate having a maximum thickness of 0.05 inch (1.27 mm), the locking tab bearing surfaces 96 and 98 may be spaced from the plane of the flange bearing surface 88 a minimum distance of 0.05 inch (1.27 mm).
Referring also to FIGS. 8-15, during operation, and referring initially to the top plan view of FIG. 8 and the corresponding bottom plan view of FIG. 9 which show the mounting plate 28 and the bushing 40 in an insertion and removal position, the locking tabs 92 and 94 are cleared by the respective locking tab clearance slots 48 and 50 , allowing the twist lock bushing 40 to be inserted into the mounting aperture 46 until the lower flange bearing surface 88 contacts the upper, exterior surface 38 of the mounting plate 28 .
Referring next to the top plan view of FIG. 10 and the corresponding bottom plan view of FIG. 11 which show the mounting plate 28 and the bushing 40 in an installed position, the bushing 40 is rotated in a first rotational direction relative to the sheet metal mounting plate 28 to the installed position of FIGS. 1, 10 and 11 . Referring particularly to the cross-sectional view of FIG. 12, in the installed position, the locking tab bearing surfaces 96 and 98 bear against the lower, interior surface 32 of the mounting plate 28 , thereby supporting the weight of the fixture 20 .
Contrasting FIG. 8 (insertion and removal position) and FIG. 10 (installed position), when viewed from the top, as the first rotational direction the bushing 40 is rotated clockwise relative to the mounting plate 28 . In practice, however, the bushing 40 remains stationary, and the mounting plate 28 is rotated counterclockwise to the installed position, when viewed from the top. From the point of view of an installer, when viewed from the bottom as in FIG. 9 (insertion and removal position) and FIG. 11 (installed position), the fixture 20 , including the mounting plate 28 , is rotated clockwise to the installed position.
To define the installed position by limiting relative rotation of the mounting plate 28 and the bushing 40 in the first rotational direction past the installed position of FIGS. 1, 10 and 11 , the mounting plate 28 includes at least one installed position rotational stop 100 . The installed position rotational stop 100 extends from either one of the exterior 30 or interior surfaces 32 , and is positioned and angularly located so as to contact a portion of the twist lock bushing 40 when the mounting plate 28 and the twist lock bushing 40 are rotated relative to each other in the first rotational direction to the installed position.
In the illustrated embodiment, the installed position rotational stop 100 takes the form of at least one interior rotational stop 100 projecting downwardly from the interior surface 32 . In FIG. 15, which is a view taken on line 15 — 15 of FIG. 10, and in FIG. 16, which is a view taken on line 16 — 16 of FIG. 10 showing the interior rotational stop 100 in cross section, the installed position or interior rotational stop 100 takes the representative form of a “dimple” formed in the sheet metal mounting plate 28 , concave when viewed from the top as in FIGS. 2 and 10, and convex when viewed from the bottom as in FIGS. 3 and 11. The installed position or interior rotational stop 100 is positioned and angularly located so as to contact one of the locking tabs 92 and 94 when the mounting plate 28 and the twist lock bushing 40 are rotated relative to each other in the first rotational direction to the installed position. In the illustrated embodiment, the installed position or interior rotational stop in the form of a dimple 100 contacts the locking tab 92 to prevent further relative rotation.
Similarly, to facilitate alignment of the locking tabs 92 and 94 with the locking tab clearance slots 48 and 50 for disengaging the mounting plate 28 and the twist lock bushing 40 in the event the fixture 20 is to be removed, there are provided elements for limiting relative rotation of the mounting plate 28 and the bushing 40 in a second rotational direction opposite the first rotational direction beyond the insertion and removal position of FIGS. 8 and 9. In the illustrated embodiment, the bushing 40 includes at least one rotational stop tab extending further radially from the radially-extending top flange 78 . A pair of rotational stop tabs 102 and 104 extend further radially from the top flange 78 , the rotational stop tab 102 extending from the top flange segment 80 , and the rotational stop tab 104 extending from the top flange segment 82 .
Correspondingly, the mounting plate 28 includes at least one exterior rotational stop 106 projecting from the exterior surface 30 . The exterior rotational stop 106 is positioned and angularly located so as to contact one of the rotational stop tabs 102 and 104 when the mounting plate 28 and the twist lock bushing 40 are rotated relative to each other in the second rotational direction to the insertion and removal position of FIGS. 8 and 9. From the point of view of an installer, when viewed from the bottom as in FIG. 9, the fixture 20 , including the mounting plate 28 , is rotated counterclockwise to the insertion and removal position.
In FIG. 17, which is a view taken on line 17 — 17 of FIG. 8, the exterior rotational stop 106 is shown in cross section, and also may be seen to take the representative form of a dimple formed in the sheet metal of the mounting plate 28 , in this case projecting upwardly. In the top plan view of FIG. 2, the exterior rotational stop 106 is convex, while in the bottom plan view of FIG. 3, the exterior rotational stop 106 is concave. In the illustrated embodiment, the exterior rotational stop 106 contacts the rotational stop tab 104 . The exterior rotational stop 106 is radially spaced from the mounting aperture 46 a sufficient distance to avoid interference with the top flange 78 , except for intentional engagement with the rotational stop tab 102 or 104 .
Finally, in order to secure the fixture 20 in the installed position, the attachment system additionally includes releasable elements for preventing relative rotational movement of the mounting plate 28 and the bushing 40 in the installed position. A variety of structures may be employed to accomplish this, such as a set screw, latch, spring, bend tab, snap pin, flexible body detent or friction fit.
In the illustrated embodiment, to prevent relative rotational movement of the mounting plate 28 and the bushing 40 in the installed position, the top flange has at least one flange set screw aperture. More particularly, a flange set screw aperture 110 formed perpendicularly through the flange 78 segment 82 angularly co-located with the rotational stop tab 104 , as well as another flange set screw aperture 112 angularly co-located with the rotational stop tab 102 . For convenience of use, the flange set screw aperture 112 is angled at an angle intermediate 0° and 90° with reference to the flange bearing surface 88 plane. At least a portion of which aperture 112 extends through the exterior rotational stop tab 104 .
Correspondingly, the mounting plate 28 has at least one mounting plate set screw aperture, in the illustrated embodiment mounting plate set screw apertures 114 and 116 , angularly located with reference to the flange set screw apertures 110 and 112 so as to be in alignment in the installed position so that a set screw 118 (FIG. 13) within the set screw apertures 110 and 114 or 112 and 116 prevents relative rotational movement of the mounting plate 28 and the bushing 40 . In the illustrated embodiment, the set screw 118 has self-tapping threads that cut into the sides of angled flange set screw aperture 112 . The end of the set screw 118 extends through the mounting plate set screw aperture 116 to provide rotational lock. Alternatively, a set screw could be threaded into the straight set screw aperture 110 , extending through the mounting plate set screw aperture 114 .
While specific embodiments of the invention have been illustrated and described herein, it is realized that numerous modifications and changes will occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit and scope of the invention.
|
A twist lock attachment system for attaching a fixture having a sheet metal mounting plate that is part of a sheet metal housing to a structural support. The exemplary fixture disclosed is a lighting fixture attached to a wiring conduit. The mounting plate has a generally circular mounting aperture. A twist lock bushing includes a tubular body correspondingly generally circular in cross section. The mounting plate and the twist lock bushing releasably engage each other by relative movement to insert the tubular body into the mounting aperture with the mounting plate and the bushing angularly oriented in an insertion and removal position with reference to each other, followed by rotation of the mounting plate and the twist lock bushing relative to each other to an installed position.
| 5
|
[0001] This application claims the benefit of U.S. provisional patent application No. 62/304,866 filed Mar. 7, 2016.
FIELD OF THE INVENTION
[0002] A manipulable elevator system is provided for a rig such as a snubbing or work-over/completion rig for the petroleum extraction industry, which permits use of a vertical pipe racking system (called a Standing Pipe Rack Back system) for jointed tubulars on a work-over or completion rig, especially useful to provide a safe vertical pipe-racking system for pressure-controlled or snubbing rig environments, without the need for a rig worker to man the monkey-board, saving operational time and expediting turnaround back to production, while maintaining operational safety.
BACKGROUND OF THE INVENTION
[0003] There is prior art having to do with top-drive rigs with vertical pipe stacking U.S. Pat. No. 7,021,374 Weatherford ('374), as well as a system designed for snubbing and work-over rigs U.S. Pat. No. 6,158,516 Cudd Pressure Control ('516), and a more general pipe-racking system U.S. Pat. No. 4,042,123 Sheldon et al ('123).
[0004] There are, however, significant differences between these systems and this invention,
[0005] For instance, '374 Weatherford deals with a top-drive system, and thus has drive equipment which must align with the upper box-end of the tubing in the elevator, inside the drive unit, and the drive unit itself is integrated in the top-end. The similarity ends with the use of hydraulic rains connected to an off-set at the upper end of the bails and to the bails themselves lower down, to effect some vertical displacement. This is not exactly the same as this invention, and takes place in a completely different working environment, although the Weatherford's hydraulic offset device has some similarities, it is effected in a different manner, on a different rig type, with a different drive system,
[0006] A block-retracting linkage between a vertical rail offset from the well's centre line and a travelling block is provided in '123 Sheldon, with a number (3) of hydraulic rams which can be actuated to move the block (and any suspended tubulars) off the well's centre line and toward and to a vertical pipe-rack means. This is different from the hydraulic bail/ram system of this invention in that the block in the system of this invention is suspended and not held by a rail-based mechanical setup.
[0007] In '516 Cudd, a combination coiled-tubing and rack-back jointed tubing rig is described, but without details of the elevator and racking system. This is relevant in that the type of tubular is commonly seen in pressure-controlled well settings, but Cudd does not disclose a hydraulic-ram bail swing system, and so is merely cited as a reference to similar rig environments in the prior art with rack-back tubular systems.
SUMMARY OF THE INVENTION
[0008] A manipulable elevator system for jointed tubulars on a rig which moves the elevator and any tubing grasped by the elevator away from (or toward) the centre-line of a wellbore being served by the rig is provided which permits use of vertical pipe racking without the need for a rig worker to man the monkey-board, especially useful to provide for safe vertical pipe-racking for pressure-controlled or snubbing rig environments, and saving operational time and expediting turnaround back to production, while maintaining operational safety; the elevator's maneuvering is controlled remotely, typically powered hydraulically.
[0009] The invention of this application, in an embodiment, may be described as follows:
1. A manipulable elevator for well operations with a work-over or completion rig to facilitate vertical racking of jointed tubulars, the elevator comprising:
(a) Remotely operable means for the elevator to grasp or release jointed tubulars (b) Remotely operable means to move the grasping means and any suspended grasped tubular away from vertical alignment with the well's centre-line.
2. The elevator of paragraph 1 where remote operations are controlled away from the well's monkeyboard. 3. The elevator of paragraph 1 where the means to move the grasping means and suspended grasped tubulars away from vertical alignment with the well's centre-line comprises:
(a) Where the well's operating equipment has a draw-works with winch, cable/tackle, an upper block and a travelling block suspended by the cable/tackle, the elevator is suspended from and below the travelling block by bails; (b) Each bail comprises an eye or fastener at its upper end, a middle elongated body, and a lower eye or faster at its lower end; (c) The travelling block has a connector for each bail, or hook/ear at or near each side of the lower end of the block, for receiving the upper eye or fastener of a bail; to (d) The elevator is suspended from and attached to the lower eye or fastener of each bail; (e) At or near each hook or ear of the travelling block is an off-set device, attached to the hook or eye, or to the block on one side, and carrying a hinge-point on another side, the hinge-point off-set vertically from the block; (f) To each hinge-point is hingedly attached the upper end of a jack; (g) The lower end of each jack is attached to the middle elongated body of a bail, each jack being attached to its bail at about the same point on each bail's body; (h) The jacks are powered to extend or retract, causing the remotely operated movement of the suspended grasping means and any suspended tubular away from vertical alignment with the well's centre-line,
4. The elevator of paragraph 3 where the grasping means is hydraulically powered and controlled. 5. The elevator of paragraph 3 where the jacks' extension and retraction is powered and controlled hydraulically. 6. The elevator of paragraph 3 where there is an alignment and retention device deployed between the upper eye of each bail and the hook or ear from which the bail is suspended, comprising:
(a) A plate with a mating plate, the two plates attached to opposite sides of the upper eye of a bail, and between which is affixed a compressible spacer; (b) The spacer is sized and placed to fill or nearly fill the gap between the lower inner surface of the hook or ear, and the upper inner surface of the eye of the bail.
7. The elevator of paragraph 3 where there is an added trough, spoon or guide mounted at about the same level as the lower end of the travelling block and around the level of the upper eye of the bails, to guide the upper end of a joint or double-joint of a jointed tubular toward and into the grasping means of the elevator.
DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1 shows a bail.
[0030] FIG. 2A shows a block with hook/ear.
[0031] FIG. 2B shows a block with attached bail, and FIG. 2C shows the same but with a deployed deformable spacer with plates for mounting.
[0032] FIG. 3 shows the apparatus of the invention in several aspects, FIG. 3A from a side showing the bails deviated from horizontal and also not deviated; FIG. 3B showing a front-on perspective; and FIG. 3C showing the apparatus with rams retracted and bails deviated.
[0033] FIG. 4 shows several elevations of a mount for the hinged attachment for the lower part of the ram to be attached to the middle of a bail.
[0034] FIG. 5 shows a block cylinder mount to offset the hinge between the upper part of a rain and the lower part of the travelling block near the ears.
[0035] FIG. 6 shows an embodiment of the guide or tubular catcher from two views; FIG. 6A from RHside elevation and FIG. 6B from above.
[0036] FIG. 7 shows several aspects of the deformable spacer and mounting plate, also called the link reactor assembly.
[0037] FIGS. 8 through 12 are elevations of a rig equipped with the apparatus to show the apparatus in sequential portrayals of parts of an operating cycle of the system manipulating tubulars; Figures A, B, and C of each of 8 - 12 are, respectively, rig view (A), expanded view of detail A (B), and expanded view of detail B, in each set of figures.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The invention has to do with a remotely operated rig-based tubular elevator system which can be used to manipulate the centering of the elevator just below a travelling block in order to in turn manipulate tubing suspended from the elevator to be more or less off-centre of the rig's operational centre-line. This provides a means of remotely handling the tubulars so that they may be vertically racked in an efficient manner. The remote control nature of the system permits it to be controlled without having a man on the rig's monkey-board, which is unsafe and in most places illegal if the rig is on a pressure-controlled well bore. There are additional features to the device and its operation to provide stability, reduce erratic operation, and assist the remote operator in aiming the elevator at the top-end of a tubing joint (or double-joint).
[0039] An elevator 170 is provided which can be opened and closed by remote control, typically comprising hydraulic-powered jaws with remote operator controls. The elevator 170 is hung from bails 10 suspended from a swivel/hook 60 just below the block 50 . The angle between the bails 10 and vertical may be adjusted by extending or retracting one or more arms 160 connected near to the swivel/hook 60 but horizontally offset a suitable small distance from vertical 115 at the swivel hook 60 by means of an offset device or block cylinder mount 110 , the arms 160 typically being hydraulically powered and controlled jacks or rams 160 .
[0040] Where the bails 10 are hingedly connected to the hook 60 of the swivel and the block 50 , a set of stabilizing means or link reaction assemblies 70 may also be affixed to the upper eye 20 of each bail. The stabilizing means 170 on each bail's eye 20 may include one or more compressible or plastic roller 90 , 95 deployed between the upper-facing inside surface of the eye 20 and the lower-facing inside surface of the mating hook 60 . In addition, the roller 90 , 95 is affixed between two plates 80 sandwiching the bail's 10 upper eye 20 . This arrangement provides a roller 90 , 95 to act as a bumper between the bail 10 and the mating hook 60 , so that when the arms (bails 10 and rams 160 ) are manipulated, for example by extending or retracting hydraulically controlled and powered jacks 160 , the bail 10 rotates from its hanging position on the hook 60 without being vertically displaced, due to the removal of slack between the eye 20 of the bail 10 and the eye of the hook 60 . In other words, the hinge is tightened so that manipulation of the angle of the bail 10 from vertical does not jump or become unstable or unpredictable by application of force by the hydraulic jack 160 control and displacement means.
[0041] By extending and retracting the hydraulic jack/arms 160 , the elevator 170 may be swung away from directly vertically below the swivel and block 50 , and toward a storage area 210 set aside on or near the drilling rig floor, to move tubulars 180 out of the way of operations centred on the well-head (and in the reverse operation, to move tubulars 180 from vertical storage 210 off-center of the well-head to swing toward and be stabbed into the wellhead connection below the block 50 ). This permits the tubulars 180 to be removed from the well and stacked vertically without an extra rig-hand, out of the way of further operations. Additionally, it permits tubulars 180 standing by the well-head against pipe rack 190 on or near a stand area 210 at the rig floor to be redeployed into the well quickly, directly from the vertical storage areas 190 , 210 , without necessity of retrieval from a distant, horizontal rack (which is typical in the prior art). These operations provide use of a rack-back 190 which would ordinarily form part of a monkey-board 200 , without having a requirement to have a man on the monkeyboard 200 above the well-head, which is dangerous and not permitted in pressure-controlled wells.
[0042] Some exemplary distances and dimensions for some components and their interrelationships: The distance of the offset 115 of the upper rams' mounting point/hinge 120 vertically from the horizontal centre-line of the block 50 is greater than zero, and preferably about 7 inches; the extended length of the rams 160 is, in an embodiment, about 39 inches; the distance from the longitudinal center of each bail 10 and the hinge point of its link cylinder mount clamp 100 is greater than zero and preferably about 6 inches; the distance along a bail 10 from its upper eye 20 suspension point to a point opposite the hinge point in an attached cylinder mount clamp 100 is in an embodiment slightly less than the fully extended length of the rams 160 ; the bails' 10 total length in an embodiment is about 72 inches; a preferred angle of deflection of the bails 10 by full retraction of the rains 160 is about 70 degrees, which causes a deviation of the elevator 170 from the well's centre-line of about 64 inches. In an embodiment rig, a monkeyboard 200 is fitted with fingered guides forming a pipe rack 190 to receive the upper end of tubulars 180 withdrawn from or ready for injection into the associated wellbore, the monkeyboard 200 and rack of fingered guides 190 or pipe rack being at or just below a height which is about the length of a pipe joint (in a double joint operation, about sixty feet or 19 meters) from the floor 210 on which the tubular 180 joint rests when not in the wellbore. The system for deviating the tubing can be operated from anywhere on the rig with remote control systems, meaning that the operator does not have to be on or near the monkeyboard 200 to control the placement of tubing 180 into the pipe rack 190 , nor removal of to tubing 180 from the rack 190 for injection into the wellbore; this permits use of the system in pressure-controlled settings.
[0043] In an embodiment, a tubing-guide system is deployed, which is essentially a catcher-guide 140 attached to or near to the elevator 170 , which provides a spoon-shaped or v-shaped guide 140 A into which the upper end of a tubing joint (or double joint) 180 may fit, in order to assist in is remotely aiming the elevator's 170 open jaws to receive and grasp the tubing 180 . Several possible embodiments are provided for, including cast metal, shaped-tubing, cut-formed-and-welded shapes, but each of which provides a broader target than the elevator's open jaws for the operator to engage the tubing 180 , which in turn guides the tubing's 180 upper end to the elevator's 170 controlled jaws. The guide 140 has a receptacle 140 A size which is preferably about 1.5-2 times the outer diameter of tubulars 180 to be handled.
[0044] Small, powerful manipulable elevator systems such as this have not been deployed on completion or work-over rigs or for snubbing operations, in particular. This may be due to the common use of endless or coil tubing in the target wells. Having said that, jointed tubing is still used in workover and completion operations, and use of single-handed vertical tubular racking systems can save tremendous time and cost, and reduce downtime and turnaround, as well as being permissible under various safety regulation regimes since no personnel are required to be on the rig's monkeyboard.
[0045] The distance between the connection of the hydraulic arms 160 near the swivel 120 and the connection of the hydraulic arms 160 to the bails 10 at the connector 105 below the elevator 50 will determine the throw-distance or offset available for moving suspended tubulars 180 off vertical alignment with the well-head and to or toward vertical stacked storage 190 , 210 . The amount of change in length of the hydraulic arms 160 will also have some bearing on the throw distance and the angular change available. These will be optimized based upon the rig-floor and stacking area location and size, height of the tubular joints, and similar constraints.
[0046] Figures in the series from 8 A through 12 C show a progression of the system's operation in use. FIGS. 8A-8C show the configuration on the rig's derrick 150 of the bails 10 , the block 50 , rams 160 , and elevator 170 as aligned vertically when pulling tubular 180 from the wellbore. FIGS. 9A-9C show the tubular 180 raised more fully (with the block 50 picked up substantially higher), the subcomponents still in essentially vertical alignment. FIGS. 10A-10C show the bails 10 deflected from vertical alignment with the block 50 , starting to swing the elevator 170 and grasped tubular 180 away from the well's centre-line—the tubular has been disconnected from lower tubulars still suspended in the well's bore. FIGS. 11A-11C shows the block 50 partially lowered (lowering all components and tubular 180 depending from the block) with the bails 10 deflected/rotated out from under the block, and the tubular coming to rest with its bottom end in the pipe stand 210 or landing area, and the tubular's 180 upper end ( FIG. 11B ) coming to rest between fingers in the pipe rack 190 on/near the monkeyboard 200 —in a different interpretation, these FIGS. 11 ) also show the tubular 180 about to be removed from the rack 190 , 210 to be stabbed (at the bottom end of the tubular 180 ) into the well's bore for joining with tubulars or equipment already in the well. FIGS. 12A-12C show another view of the tubular 180 being racked into the pipe rack 190 , 210 by deflection of the bails 10 to move the elevator 170 into place for that operation.
[0047] The descriptions in this part are meant to be illustrative and not limiting, and it will be apparent to one skilled in the art of building or operating completion or work-over or service rigs, particularly in pressure-controlled wells, that the described arrangements of apparatus and the methods of use are merely illustrative of applications of the principles of the invention, and that many other embodiments and modifications may be made without departing from the spirit and scope of the invention as delineated by the claims.
[0000]
LEGEND FOR THE REFERENCE NUMERALS
10
Bail
10a
Displaced bail
10b
Bail, not displaced
20
Upper Eye of Bail
30
Elongated body of Bail
40
Lower Eye of Bail
50
Travelling Block
60
Hook or Ear on or near (below) Block
70
Link Reaction Assembly
80
Link Plate
90
Link wear block
95
Link load block
100
Bail Connector Clamp to Ram Bottom End
105
Hinge point of Bail Connector Clamp
110
Vertical displacement part of connector and hinge
115
Displacement from vertical of upper ram hinge from
travelling block
120
Hinge points on upper ram connector to block
130
Plate for attachment of upper ram connector to block
140
Tube guide/catcher
140A
Opening distance of catcher (1.5-2X tubing diameter)
150
Derrick
160
Ram
170
Elevator
180
Tubular
190
Pipe rack
200
Monkeyboard
210
Pipe stand
|
A manipulable elevator system for jointed tubulars on a service, work-over or completion rig which moves the elevator and any tubing grasped by the elevator away from (or toward) the centre-line of a wellbore being served by the rig is provided which permits use of a vertical pipe racking without the need for a rig worker to man the monkey-board, especially useful to provide for safe vertical pipe-racking for pressure-controlled or snubbing rig environments, and saving operational time and expediting turnaround back to production, while maintaining operational safety; the elevator's maneuvering controlled remotely, typically powered hydraulically.
| 4
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. patent application Ser. No. 11/086,055 entitled “FIBER OPTIC SENSING DEVICE AND METHOD OF MAKING AND OPERATING THE SAME” filed Mar. 22, 2005, now U.S. Pat. No. 7,421,162 which is herein incorporated by reference for all purposes.
BACKGROUND
The present invention relates generally to fiber optic sensing devices, and more particularly, to a fiber optic sensing device for detecting multiple parameters in an environment or element, for example. Indeed, the present invention provides advantages related to the use of fiber optic sensing devices in harsh environments, for instance.
Various sensing devices are known and are generally in use. For example, thermocouples are used for measuring the temperature in components of a device, such as exhaust systems, combustors, compressors and so forth. Yet other sensing systems are employed to detect physical parameters such as, strain or temperature in an infrastructure. As one example, Bragg grating sensors are often employed. However, such conventional sensing devices are limited by the operational conditions in which they may be employed. For example, conventional sensing devices are often limited to relatively mild temperature conditions and, as such, limited operational temperature ranges. Indeed, conventional devices are limited to temperatures between +80° C. to +250° C., depending upon the fiber grating coating materials.
As such, it is difficult to measure temperatures for components in high-temperature environments like turbines and engines. Further, for large components, a relatively large number of discrete thermocouples may be required to map the temperatures. Such discrete thermocouples may not be scalable to meet a desired spatial resolution that is generally beneficial for accurate thermal mapping of system components, which can then used to control and optimize the operation of such systems with the objectives of improving efficiency and output. A more accurate and improved spatial resolution thermal mapping is necessary to control such systems (gas turbines, steam turbines, coal-fired boilers, etc.) with more accuracy and fidelity to meet requirements such as better efficiency and output. The sensing devices for gas components such as NOx, CO and O2 also have a similar limitation in terms of accuracy and spatial resolution. A more accurate and spatially dense gas sensing would facilitate more effective and efficient emissions control for gas turbines and coal-fired boilers.
Accordingly, conventional sensing devices present limitations when employed in high temperature and/or harsh environments such as, gas/steam turbine exhausts, coal-fired boilers, aircraft engines, downhole applications and so forth. For example, conventional Bragg grating sensors employ a doped or chemical grating that breaks down in high temperature settings (e.g., a gas turbine exhaust that may reach temperatures of 600° C. or higher).
Certain other conventional systems employ Bragg grating sensors for measuring and monitoring a parameter in an environment. Such sensors utilize a wavelength encoding within a core of the sensor to measure a parameter based upon a Bragg wavelength shift that is generated on illumination of the grating through an illumination source. Thus, environmental effects on the periodicity of the grating alters the wavelength of light reflected, thereby providing an indication of the environmental or elemental effect, such as, temperature or strain, for example. However, it is difficult to simultaneously detect multiple parameters, such as temperature and gas, through a single conventional Bragg grating sensing element. Further, multiple spectral signals at different wavelengths may be required to separate the effect of multiple sensed parameters from one another. Such separation of sensed parameters is conventionally a difficult and time-consuming process.
In certain conventional sensor systems, an additional grating element encapsulated in a different material is placed in series with an existing grating element for separating the effects of two different parameters, such as temperature and strain. Moreover, such systems require overwriting gratings at the same fiber location, which often present difficulties during the manufacturing the fiber grating for the sensor. In summary, conventional Bragg grating sensors do not facilitate discernment of what environmental or elemental factor influenced the sensor, rather only the physical changes in the sensor itself are readily detectable.
Therefore, there is a need for improved sensing devices.
BRIEF DESCRIPTION
In accordance with one exemplary embodiment, the present technique provides a fiber optic grating sensor cable. Each exemplary fiber grating includes a core having a first index of refraction and a plurality of grating elements each having an index of refraction different from the first index of refraction. The core includes a first pair of grating elements configured to reflect a first wavelength of light in phase and a second pair of grating elements configured to reflect a second wavelength of light in phase. The core also includes a third pair of grating elements configured to reflect the first wavelength of light in phase, wherein at least one grating element of the second pair of grating elements is located between at least one grating element of the first pair and at least one grating element of the third pair. The fiber optic sensor cable also includes a cladding disposed circumferentially about the core.
In accordance with yet another exemplary embodiment, the present technique provides a method of detecting a plurality of parameters. The method includes providing a source of light to a fiber optic sensor cable having a plurality of grating elements and comprising first, second and third portions, wherein adjacent gratings in the first and third portions are at a first distance from one another and adjacent gratings in the second portion are at a second distance from one another, and wherein the second portion is located between the first and third portions. The method also includes detecting light emitted from the fiber optic sensor cable.
In accordance with another exemplary embodiment, the present technique provides a distributed sensor system for sensing multiple parameters in a harsh environment. The sensor system includes a plurality of sensors disposed on a distributed fiber optic grating sensor cable, wherein each of the plurality of sensor comprises a core having a first index of refraction and a plurality of mechanically altered portions each having an index of refraction different than the first index of refraction.
DRAWINGS
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
FIG. 1 is a diagrammatical representation of a fiber optic sensing system for detecting multiple parameters of an environment and/or element, in accordance with an exemplary embodiment of the present technique;
FIG. 2 is a diagrammatical representation of a fiber optic sensor array cable having aperiodic spaced grating structures with the refractive index modulated by a periodic or an aperiodic sequence, in accordance with an exemplary embodiment of the present technique;
FIG. 3 is a diagrammatical representation of the core of a fiber optic sensor cable including aperiodic grating structures;
FIG. 4 is a diagrammatical representation of waveforms of light generated by aperiodic grating structures of the fiber optic sensor cable of FIG. 3 , in accordance with an exemplary embodiment of the present technique;
FIG. 5 is a diagrammatical representation of a Bragg grating fiber optic cable of FIG. 3 during normal conditions, in accordance with an exemplary embodiment of the present technique;
FIG. 6 is a diagrammatical representation of a Bragg grating fiber optic cable of FIG. 3 during stressed conditions, in accordance with an exemplary embodiment of the present technique;
FIG. 7 is a flow chart of a process for manufacturing the fiber optic sensor cable of FIGS. 1-3 , in accordance with an exemplary embodiment of the present technique;
FIG. 8 is a diagrammatical representation of a distributed fiber sensor system, in accordance with an exemplary embodiment of the present technique;
FIG. 9 is a diagrammatical representation of a fiber optic sensor cable with a micromachined aperiodic grating structure, in accordance with an exemplary embodiment of the present technique;
FIG. 10 is a diagrammatical representation of a system for inscribing the fiber grating structures of FIG. 3 , in accordance with an exemplary embodiment of the present technique;
FIG. 11 is a diagrammatical representation of an application having the distributed fiber sensing system of FIG. 8 in accordance with an exemplary embodiment of the present technique; and
FIG. 12 is a diagrammatical representation of another application having the distributed fiber sensing system of FIG. 8 in accordance with an exemplary embodiment of the present technique.
DETAILED DESCRIPTION
Referring now to drawings, FIG. 1 illustrates an exemplary fiber optic sensing system 10 for detecting parameters of an environment and/or object 12 . Although the present discussion focuses on sensing devices and systems, the present technique is not limited to sensing field, but is also applicable to other modalities, such as, optical filters, data transmission, and telecommunications, among others. Accordingly, the appended claims should not be limited to or by the exemplary embodiments of the following discussion. The fiber optic sensing system 10 includes a fiber optic sensing device 14 that, in turn, includes a grated cable 16 . As illustrated, the cable 16 is disposed within the element 12 , causing changes in the element 12 to translate to the cable 16 . The grated cable 16 includes a core that has a plurality of grating elements arranged in an aperiodic pattern, which is described in detail below. In the present discussion, a grating element refers to a variance in the index of refraction in comparison to the index of refraction of the core. Such grating elements may be a result of a micromachining process, such as diamond saw cutting, or a chemical process, such as doping, and both processes are discussed further below.
Further, the fiber optic sensing system 10 includes a light source 18 that is configured to illuminate the core of the grated cable 16 . This illumination facilitates the generation of reflected signals corresponding to a grating period of the grated cable 16 . The system 10 also includes an optical coupler 20 to manage incoming light from the light source 18 as well as the reflected signals from the grated cable 16 . Indeed, the coupler 20 directs the appropriate reflected signals to a detector system 22 .
The detector system 22 receives the reflected optical signals from the grated cable 16 and, in cooperation with various hardware and software components, analyzes the embedded information within the optical signals. For example, the detector system 22 is configured to estimate a condition or a parameter of the object 12 based upon a diffraction peak generated from the plurality of grating elements of the grated cable 16 of the fiber optic sensing device 14 . In certain embodiments, the detector system 22 employs an optical coupler or an optical spectral analyzer to analyze signals from the fiber optic sensing device 14 . Depending on a desired application, the detector system 22 may be configured to measure various parameters in the environment 12 . Examples of such parameters include temperatures, presence of gases, strains and pressures, among others.
Advantageously, as discussed further below, the exemplary cable 16 generates multiple strong diffraction peaks, thereby facilitating the segregation of the various influencing parameters on the cable 16 . The information developed by the detector system 22 may be communicated to an output 24 such as, a display or a wireless communication device. Advantageously, gleaned information, such as environmental or object conditions, may be employed to address any number of concerns or to effectuate changes in the environment or object 12 itself.
FIG. 2 illustrates an exemplary fiber optic sensor array cable 26 having an aperiodic grated refractive index modulation, in accordance with an embodiment of the present technique. The fiber optic sensor cable 26 includes a core 28 and a cladding 30 that is disposed circumferentially about the core 28 . A portion of the cladding 30 has been removed to better illustrate the underlying core 28 . The core 28 includes a series of grated elements 32 that are configured to reflect in phase wavelengths of light corresponding to a grating period of the grated elements 32 . As illustrated, distances between adjacent gratings are arranged in an aperiodic pattern that will be described in detail below with reference to FIG. 3 . During operation, an input broadband light signal 34 is provided to the fiber optic sensor cable 26 by the light source 18 and a portion of the input broadband light signal 34 is reflected by a respective grating element 32 in phase and corresponding to certain wavelengths of light, while remaining wavelengths are transmitted as represented by a transmitted signal 36 .
Referring now to FIG. 3 , a grated portion of a core of a fiber optic sensor cable 38 is illustrated. As illustrated, the fiber optic sensor cable 38 is formed of a core 40 and cladding 30 that is disposed about the core 40 . The cladding 30 provides for near total internal reflection of light within the cable 38 , thereby allowing light to be transmitted by and axially through the cable 38 . The cable 38 also includes a plurality of grating elements represented generally by reference numeral 42 . In one embodiment, the core 40 comprises a fused silica fiber. In another embodiment, the core 40 comprises a sapphire fiber. The plurality of grating elements 42 has an index of refraction different from that of core 40 . In this embodiment, the index of refraction of the grating elements 42 is lower than that of the core 40 . By way of example, the core 40 may have an index of refraction of 1.48, while the grating element 42 may have an index of refraction of 1.47, for instance. As discussed below, the index of refraction of the various grating elements 42 , and the distances between these grating elements 42 defines the wavelength of light reflected in phase by the grating elements 42 .
The exemplary portion of the core 40 shown in FIG. 3 includes various portions that effect how light is transmitted through the fiber optic sensor cable 38 . In the illustrated embodiment, the core 40 includes a first portion 44 where the distance between adjacent grating elements 42 is at a first distance 46 . This first distance 46 defines a first wavelength of light that will be reflected in phase by the pair of grating elements 42 in the first portion 44 . By way of example, the distance between the first pair of grating elements 42 is generally of the same order of magnitude as that of the wavelength of the reflected light, e.g., 0.775 μm, for instance. The core also includes a second portion 48 where the distance between adjacent grating elements 42 is at a second distance 50 . This second distance 50 , which is different than the first distance 46 defines a second different wavelength of light that will be reflected in phase by the pair of second grating elements 42 in the second portion 48 . In addition, the core 40 includes a third portion 52 where the distance between grating elements 42 is at the first distance 46 . Thus, the grating elements 42 in the third portion 52 reflect the first wavelength of light in phase, like the first portion 44 . In this embodiment, the second portion 48 is disposed between the first and third portions 44 and 52 .
As can be seen, the distances between adjacent gratings 42 have an aperiodic pattern. That is, the distances between adjacent gratings 42 along a longitudinal axis of the core 40 alternate between the first and second distance 46 and 50 . It is worth noting that the present oscillation between the first and second distances 46 and 50 to establish an aperiodic pattern is merely but one example. Indeed, a number of aperiodic patterns may be envisaged. In the illustrated embodiment, the indices of refraction of the core 40 and the gratings 42 are modulated according to Fibonacci sequence. The indices of refraction of the core 40 and the gratings 42 are modulated such that there is a relatively higher refractive index modulation with aperiodic sequence in the core 40 as compared to the refractive index modulation circumferentially surrounding the cladding 30 . Further, the grating structure of the fiber core 40 may be defined by an aperiodic sequence of blocks n a and n b and a constant τ. By way of example, n a is index of refraction of 1.49 and n b is an index of refraction of 1.45.
In this embodiment, the sequence for the refractive index modulation is based upon the following equation:
S 3 ={S 2 ,S 1 }, . . . S n ={S j-1 ,S j-2 } for j≧ 2 (1)
where S 1 =n a corresponding to core region having the first effective index of refraction; and
S2=n a n b corresponding to grating elements having an index of refraction different than the first index of refraction.
Thus, the diffraction spectrum generated by the above defined grating structure will include a first Bragg diffraction peak that corresponds to the first wavelength of light in phase and a second Bragg diffraction peak that corresponds to the second wavelength of reflected light in phase and a plurality of diffraction peaks that are determined by a modulation periodicity and a diffraction wave vector. In this exemplary embodiment, the modulation periodicity is based upon the following equation:
Λ= d ( n A )+τ d ( n B ) (2)
where d(n A ) and d(n B ) are fiber lengths of the refractive index changed and unchanged areas respectively with τ being the golden mean with a value of 1.618.
Further, the diffraction wave vector is determined by two indices (n,m):
k ( n,m )=( m+τn )/Λ (3)
where Λ is a quasiperiodicity of the aperiodic grating structure and n, m are discrete wave numbers.
In the illustrated exemplary embodiment, the diffraction of light may occur when the discrete wave numbers satisfy the range n,m=0, ±1, ±2 . . . .
Further, the Bragg diffraction wavelength having relatively high intensity is given by:
λ B ( n , m ) = 2 n eff Λ ( m + n τ )
Advantageously, a plurality of generated diffraction peaks facilitate simultaneous multiple parameters measurements. Examples of such parameters include temperature, strain, pressure and gas.
The illustrated aperiodic pattern of the gratings 42 of the fiber optic sensing device 38 enables the fiber optic sensing device 38 to generate a plurality of diffraction peaks simultaneously from emitted light from the core 40 . In this exemplary embodiment, the plurality of diffraction peaks is representative of a plurality of sensed parameters such as, temperature, strain and so forth. The grated cable of the fiber optic sensing device 38 is configured to generate first and second diffraction peaks that contain embedded information representative of first and second sensed parameters. Such first and second diffraction peaks are then detected by the detector system 22 (see FIG. 1 ) for estimating the first and second sensed parameters. Advantageously, the grated cable allows the fiber optic sensing device 38 to generate the first and second diffraction peaks to appear in fiber low-loss transmission windows and also with substantially comparable efficiencies. The first and second diffraction peaks may be employed for simultaneously measuring the first and second sensed parameters such as temperature and strain. These first and second diffraction peaks corresponding to first and second sensed parameters are described below with reference to FIG. 4 .
FIG. 4 illustrates exemplary waveforms 54 of light generated by the aperiodic grated cable of the fiber optic sensing device of FIG. 3 . The abscissa axis 58 of the waveforms 54 represents a wavelength of the light signal and the ordinate axis 60 of the waveforms 54 represents an intensity of the light signal. In the illustrated embodiment, an input broadband light signal is represented by a waveform 56 and a reflected signal from the grated cable is represented by reference numeral 62 . As can be seen, the reflected signal 62 from the core of the grated cable includes first and second diffraction peaks 64 and 66 that may be processed by the detector system 22 (see FIG. 1 ) to estimate the first and second sensed parameters. Further, the transmitted signal is represented by a reference numeral 68 that transmits wavelengths that are not corresponding to the grating period of the grated cable 32 . Thus, the aperiodic grated structure facilitates the generation of strong first and second diffraction peaks 64 and 66 with comparable diffraction efficiencies that can be detected by a single detector. These detected diffraction peaks 64 and 66 may then be processed to detect multiple parameters of the environment or object 12 (see FIG. 1 ). Advantageously, these diffraction peaks 64 and 66 can be maintained over relatively long lengths of cable without signal deterioration due to losses.
Referring now to FIG. 5 , the Bragg grating fiber optic sensor cable 70 of FIG. 3 during normal conditions is illustrated. In the illustrated embodiment, the distance between a first pair of grating elements 42 is at a first distance 72 and the distance between a second pair of grating elements 42 is at a second distance 74 . As described earlier, the illustrated aperiodic pattern of the distance between adjacent grating elements enables generation of two diffraction peaks from the fiber optic sensor cable 70 that are representative of two sensed parameters. In operation, when the fiber optic sensing device 70 is subjected to a stress for example, a temperature, or a strain, the distance between the adjacent grating elements changes in response to the applied stress as can be seen in FIG. 6 .
FIG. 6 illustrates an exemplary Bragg grating fiber optic sensor cable 76 of FIG. 3 during stressed conditions. In this embodiment, the length of the fiber optic sensor cable 76 changes in response to an environmental condition, such as an applied stress and temperature. Therefore, the distance between the first pair of elements 42 changes from the first distance 72 (shown in FIG. 5 ) to a new distance 78 , and this new distance 78 may be greater or lesser than the original distance 72 . Similarly, the distance between the second pair of elements 42 changes from the second distance 74 (shown in FIG. 5 ) to a new distance 80 . Again, this new distance 80 may be greater or lower than the second distance 74 depending on the influence of the environmental factors on the cable 76 . On illumination of the fiber optic sensing device 76 through an illumination source, diffraction peaks are generated from the light emitted from the fiber optic sensing device 76 . These diffraction peaks correlate to a change in length of fiber optic sensing device such as represented by the change in first and second distances 78 and 80 to estimate parameters corresponding to the diffraction peaks.
Similarly, in a gaseous environment, gases may interact with the fiber cladding, causing a change in the index of refraction resulting in cladding modes wavelength shifts that may be detected by the fiber optic sensing device 76 to simultaneously distinguish the temperature and gas effects. In this embodiment, the gases in the environment are detected from the optical properties variation of a sensing film that is coated on the grating elements of the fiber optic sensing device 76 . The absorption and adsorption properties of a gas varies the cladding absorption properties and thereby the index of refraction. Thus, the reflectance and transmittance spectra associated with the light through the grating of the sensing device 76 enables the separation of the environmental effects of the temperature and strain from gas sensing. That is to say, the effects of the environment change the wavelengths of light reflected in phase by the cable 76 . Further, by comparing this change with the diffraction peaks of the cable in its quiescent state, the magnitude of the environment effects can be determined.
The fiber optic sensing device of FIGS. 1-3 may be manufactured by an exemplary process as represented by reference numeral 82 in FIG. 7 . The process 82 begins at step 84 where a core is provided. In this embodiment, the core has a first index of refraction. At step 86 , a first pair of grating elements is provided wherein the distance between adjacent grating elements of the first pair is at a first distance. In the illustrated embodiment, the first pair of grating elements is configured to reflect a first wavelength of light in phase. At step 88 , a second pair of grating elements is provided that is configured to reflect a second wavelength of light in phase. The distance between adjacent grating elements of the second pair is at a second distance. In this embodiment, the second distance is different than the first distance. As represented by step 90 , a third pair of grating elements that is configured to reflect the first wavelength of light in phase is provided. In this embodiment, at least one grating element of the second pair of grating elements is located between at least one grating element of the first pair and at least one grating element of the third pair. As illustrated by step 92 , a cladding is disposed circumferentially about the core. In one embodiment, the first, second and third pair of grating elements are provided through an ultraviolet light exposure laser inscribing technique. In another embodiment, the first, second and third pair of grating elements are provided by disposing an optical coating on the core and subsequently selectively removing portions from the core along a longitudinal axis of the core. In certain embodiments, the optical coating on the core may be etched through a slit pattern mask to provide the first, second and third pair of grating elements.
The fiber optic sensing device manufactured by exemplary process of FIG. 7 may be employed for sensing parameters in a distributed environment. FIG. 8 illustrates an exemplary distributed fiber sensor system 100 for sensing parameters over a relatively large environment 102 . In the illustrated embodiment, the sensor system 100 includes a plurality of sensors 104 disposed on a distributed cable 106 . Further, each of the plurality of sensors 104 includes a grated cable 108 . In certain embodiments, the grated cable 108 comprises a plurality of grating elements arranged in a periodic pattern. In certain other embodiments, the grating cable 108 comprises a plurality of grating elements arranged in an aperiodic pattern as described above. In the distributed sensor system 100 , data regarding different locations of the environment can be obtained by evaluating the changes in the diffraction peaks reflected by the various sensors 104 .
In operation, the distributed fiber sensor system 100 may be placed in the environment 102 for detecting parameters of environment such as temperature, strain and so forth. The distributed fiber sensor system 100 is illuminated by a light source 110 as represented by the reference numeral 112 and respective reflective and transmitive signals 114 and 116 are then received by an optical spectral analyzer 118 . A coupler 20 may be coupled to the light source 110 and to the optical spectral analyzer 118 to combine the input and the reflected signal. The optical spectral analyzer 118 measures the wavelength spectrum and intensity of the received signals to estimate a parameter of the environment 102 . Finally, the detected signals representative of the sensed parameters are transmitted to a data acquisition and processing circuitry 120 .
Referring now to FIG. 9 , a fiber optic sensor cable 122 with a micro machined or mechanical structure is illustrated. The fiber optic sensor cable 122 includes a core 124 and a plurality of mechanically altered portions 126 . Additionally, the fiber optic sensor cable 122 includes a cladding 128 disposed about the core 124 and the mechanically altered portions 126 . In the illustrated embodiment, each of the mechanically altered portions comprises portions with diameter different than the diameter of the core. In certain embodiments, a micromachining process, such as diamond saw cutting process, may be employed for selectively removing portions of the core 124 to form the mechanically altered portions 126 by altering the diameter of the core 124 . This micromachining process enables to create areas of refractive index that is different than the index of refraction of the core 124 and this variance in index of refraction functions as grating elements for the fiber optic sensor cable 122 .
In certain exemplary embodiments, the distance between adjacent grating elements, such as represented by reference numeral 130 , may vary along a longitudinal axis of the core 124 to form an aperiodic grating structure (as shown in FIG. 9 ). As described above with reference to FIG. 3 , the aperiodic grating structure may be defined by an aperiodic sequence of blocks n a and n b and a constant τ and the sequence is based upon the following equation:
S 3 ={S 2 ,S 1 }, . . . S n ={S j-1 ,S j-2 } for j≧ 2 (1)
where S 1 =n a that corresponds to core region having the first index of refraction; and
S2=n a n b that corresponds to grating elements having an index of refraction different than the first index of refraction.
It should be noted that, the mechanically altered portions 126 of the grating structure manufactured by the micromachining processes enable the fiber optic sensor cable 122 to be employed in harsh environments such as a gas turbine exhaust, a steam turbine exhaust, a coal-fired boiler, an aircraft engine, a down hole application and so forth where the temperatures reach 600° C. and above, for instance.
The aperiodic grating structure described above may also be formed by employing a point-by-point laser inscribing technique. Referring now to FIG. 10 , a system 132 for inscribing Bragg grating is illustrated. The system 132 includes a phase mask 134 disposed on a fiber core 136 . The system 132 also includes a UV laser 138 to generate a beam that is directed towards the phase mask 134 . Further, the beam generated from the UV laser 138 may be focused with a plane cylindrical lens 140 towards the fiber core 136 . In this embodiment, the phase mask 134 is employed to spatially modulate and diffract the UV beam from the UV laser 138 to form an interference pattern. The interference pattern induces a refractive index modulation that creates a Bragg grating structure 142 in the fiber core 136 . The system 132 also includes a broadband light source 144 and an optical spectrum analyzer 146 for detecting the Bragg wavelength of the light wave that is received by the optical spectrum analyzer 146 from the fiber core 136 .
The various aspects of the technique described above may be used for sensing multiple parameters such as, temperature, strain, pressure and fossil fuel gas in a variety of environments. In certain embodiments, the technique is employed for detecting parameters in a harsh environment such as those subjected to high temperatures. For example, the technique may be used for providing a thermal mapping in an exhaust system by measuring the temperature at multiple grating locations that are dispersed circumferentially about the exhaust system, or a combustor, or an output stage of a compressor of a jet engine. FIG. 11 illustrates an exemplary application 150 having the distributed fiber sensor system of FIG. 8 .
Referring now to FIG. 11 the exemplary application 150 includes a gas turbine 152 having various components, such as a compressor 154 , a multi-chamber combustor 156 and a turbine 158 disposed about a shaft 160 . As illustrated, a distributed fiber sensor system 162 is coupled to the turbine 158 for providing a spatially dense exhaust temperature measurement 164 from the turbine 158 . The temperature measurements 164 obtained by the distributed fiber sensor system 162 may be utilized for a substantially accurate control of the performance of the gas turbine 152 . In the illustrated embodiment, the temperature measurements 164 may be utilized for determining combustor firing temperatures 166 through a model-based estimation technique or an empirical method 168 . The model based estimation technique 168 utilizes an inverse of a physics based model that maps the combustor firing temperatures 166 to the exhaust temperatures 164 . Alternatively, the empirical method 168 may utilize unload data of the turbine 158 to facilitate mapping of the exhaust temperatures 164 to the individual combustor chambers of the multi-chamber combustor 156 . Advantageously, the spatially denser and more accurate exhaust temperature profile facilitated by the present exemplary embodiment increases the accuracy and the fidelity of the model based estimation and the empirical method.
The estimated combustor firing temperatures 166 may be utilized for adjusting fuel distribution tuning 170 to ensure that all chambers of the multi-chamber combustor 156 are firing uniformly and have dynamic pressures and emissions that are within pre-determined thresholds. Advantageously, the technique provides a substantial reduction in combustion chamber-to-chamber variation for emissions and firing temperatures 166 .
FIG. 12 illustrates another exemplary application 172 having the distributed fiber sensor system of FIG. 8 . As illustrated, the application 172 includes a coal fired boiler 174 for providing steam to steam turbines for power generation. The coal fired boiler 174 includes a distributed fiber sensor system 176 for measuring parameters such as temperatures, exhaust gases and so forth. In this embodiment, the measurement of parameters via the distributed fiber sensor system 176 may be employed to model relationship between inputs such as air and fuel flows to a burner 178 of the coal fired boiler 174 and exhaust parameters 180 from the boiler 174 . Further, a model 182 may be employed to correlate the burner air and fuel flow to the exhaust parameter measurements 180 and to tune the air and fuel flows 184 via a model based optimization method 186 . Advantageously, the exemplary sensor can provide more accurate and dense temperature profiles, CO and O 2 measurements in the exit plane of the boiler 174 . Thus, air and fuel flows 184 may be adjusted to reduce exit temperatures, gas emissions such as CO while meeting desired output requirements.
Similarly, the technique may be used for mapping a temperature distribution in components such as gas turbines, steam turbines, distillation columns and so forth. The fiber optic sensing device as described above may be employed to estimate multiple parameters in an aircraft engine such as, a compressor blade tip clearance, compressor exit temperature, combustor temperature and for detecting exhaust tail pipe fire. For example, in detecting an exhaust tail pipe fire, the exemplary sensor described above can differentiate between abnormally high temperatures from normal elevated temperatures in locations that are not observable by the crew but are accessible by the sensor. Further, the fiber optic sensing device may be also employed for monitoring downhole sensing in an oil and gas drilling rig. The fiber optic sensing device may be employed in various other applications such as a narrow band reflector, a broadband mirror, a wavelength division multiplexing (WDM) filter, a differential photonic sensor and so forth.
Advantageously, in accordance with embodiments of the present technique, mapping temperature and fossil fuel gas species helps improve turbine and engine power production efficiency, thereby saving energy. For example, the exemplary periodic and aperiodic sapphire fiber-grating sensor array will simultaneously distinguish the temperature and gas by monitoring cladding modes wavelength shifts. The need for temperature sensing in industrial sensing and control applications has to simultaneously measure emissions (NOX, CO, O2, H2, etc.) of coal-fired boilers, gas turbines or steam turbine. The combined sensing helps optimize the turbine energy usage efficiency. The speed, accuracy and the spatial resolution of available extractive (offline) or non-extractive (online) gas sensing systems available today are limited. There is a need to improve speed of response, accuracy, and spatial resolution of such sensing systems so as to enable for instance better and possibly active closed loop emissions control for power generation equipment. For that matter, any control/optimization application that needs accurate and/or spatially denser gas sensing is a good candidate application for the multi-parameter sensors described herein.
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.
|
In accordance with one exemplary embodiment the invention provides a multi-parameter fiber optic sensing system with an aperiodic sapphire fiber grating as sensing element for simultaneous temperature, strain, NO x , CO, O 2 and H 2 gas detection. The exemplary sensing system includes an aperiodic fiber grating with an alternative refractive index modulation for such multi-function sensing and determination. Fabrication of such quasiperiodic grating structures can be made with point-by-point UV laser inscribing, diamond saw micromachining, and phase mask-based coating and chemical etching methods. In the exemplary embodiment, simultaneous detections on multi-parameter can be distributed, but not limited, in gas/steam turbine exhaust, in combustion and compressor, and in coal fired boilers etc. Advantageously, the mapping of multiple parameters such as temperature, strain, and gas using sapphire aperiodic gratings improves control and optimization of such systems directed to improve efficiency and output and reduce emissions.
| 6
|
The present application is a continuation of U.S. application Ser. No. 11/077,361, filed Mar. 11, 2005, now issued U.S. Pat. No. 7,931,671, the entire contents of which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates generally to the field of sealing devices for the sealing of a percutaneous puncture in a vessel wall, and in particular to the class of sealing devices that comprises an intra-arterial member and an extra-arterial member, which are sandwiching the vessel wall and are held together by a retaining member, and more particularly to a sealing device which at least partly is made from a polymer having a shape memory.
BACKGROUND OF THE INVENTION
In the U.S. Pat. No. 6,508,828, which is assigned to the present assignee, a sealing device is disclosed for sealing a puncture hole in a vessel wall. The sealing device comprises an inner sealing member, an outer member, and a retaining member. The inner sealing member is adapted to be positioned at the inner wall of a vessel, while the outer member is adapted to be positioned at the outer wall of the vessel. In use, the inner and outer members are sandwiching the vessel wall, and are held together by the retaining member to thereby seal the puncture hole in the vessel wall. The retaining member and the outer member are thereby held in place by friction acting between the retaining member and the outer member. The contents of U.S. Pat. No. 6,508,828 are hereby incorporated herein by reference.
Other examples of sealing devices that comprise an inner member and an outer member, which are held together by an elongated retaining member, such as a suture or filament, can be found in, for example, U.S. Pat. Nos. 5,593,422 and 5,620,461. In U.S. Pat. No. 5,342,393, the retaining member is in the form of a stem that extends from the inner member.
Although at least a sealing device designed according to the teachings of U.S. Pat. No. 6,508,828 in practice has proven to work very well, its sealing function can be improved, and in particular the friction locking between the retaining member and the outer member can be enhanced.
SUMMARY OF THE INVENTION
The general object of the present invention is therefore to provide a sealing device with an enhanced sealing capacity and which is more reliably positioned at a vessel wall. Preferably, the invention should be applicable to an existing sealing device with a minimum of change of the design of the components of the sealing device, and without changing the practical handling of the sealing device.
The above-mentioned objects are achieved with a sealing device as described below.
The present invention is related to a sealing device comprising an intra-arterial (inner) member and an extra-arterial (outer) member, which are held together by a retaining member. In use, the inner member is through a puncture hole in a vessel wall introduced into the lumen of the vessel, and is then retracted until it is in close contact with the inner vessel wall. The retaining member, which is attached to the inner member, then extends through the puncture hole and holds the inner member tightly in a fixed position. The outer member is then advanced along the retaining member until the outer member is contacting the outside of the vessel wall. When the operation is completed, the outer and inner members will thereby sandwich the vessel wall and the puncture hole therein, while the outer member and the retaining member are held together by friction locking.
According to the invention, the sealing performance of a sealing device, and in particular the locking function between a retaining member and an outer member can be improved by making the retaining member and/or the outer member from at least one polymer having a so-called shape memory. An object, i.e. the retaining member or the outer member, being made from such a polymer is characterized by having a first shape at a first temperature and a second shape at a second temperature.
In a first embodiment of the present invention, a retaining member, which is in the form of a stem extending from an inner member, is made from a polymer having shape memory. The stem would then have a first (smaller) diameter at a first temperature and a second (larger) diameter at a second temperature. A sealing device comprising this retaining member would be positioned at a vessel wall, with the stem being in the smaller diameter configuration, and the stem would then expand to its larger diameter configuration, to thereby provide a large amount of friction between the stem and an outer member which is positioned around the stem.
Rather than expand as a whole, the stem could also be provided with protrusions which at a first temperature are positioned close to the stem body, while at a second temperature are protruding away from the stem body to thereby prevent an outer member from sliding off the stem. This design is shown in a second embodiment of the invention.
In a third embodiment, the friction locking is provided by a spiral element which is disposed inside a retaining member in the form of a suture. The spiral element is made from a shape memory polymer, such that the spiral element has a first, small diameter during the introduction of a sealing device, of which the spiral element is a part, and a second, larger diameter when the sealing device has been positioned at a vessel.
Also an inner member could be made from a shape memory polymer. In a fourth embodiment of the present invention, the inner member and an outer member are made from a shape memory polymer such that the inner and outer members are essentially flat at a first temperature, and exhibit a concave shape at a second temperature. When the inner and outer members have been positioned such that they sandwich a vessel wall, the inner and outer members would then assume the concave shape, with their concave sides facing the vessel wall, to thereby squeeze the vessel wall between them.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a and 1 b are schematic illustrations of a first embodiment of the present invention in a first state and in a second state.
FIGS. 2 a and 2 b are schematic illustrations of a second embodiment of the present invention in a first state and in a second state.
FIGS. 3 a and 3 b are schematic illustrations of a third embodiment of the present invention in a first state and in a second state.
FIGS. 4 a and 4 b are schematic illustrations of a fourth embodiment of the present invention in a first state and second state.
DETAILED DESCRIPTION OF THE INVENTION
A sealing device 1 according to the present invention is schematically illustrated in FIGS. 1 a and b . The sealing device 1 comprises an inner member 2 and an outer member 3 , which are held together by an elongated retaining member 4 . The retaining member 4 protrudes from the inner member 2 , and extends through a hole in the outer member 3 . During the positioning operation of the sealing device 1 , the inner member 2 is positioned at an inner wall of a vessel, and the outer member 3 is then slid along the retaining member 4 into abutment against an outer wall of the vessel. According to the invention, the retaining member 4 is made from at least one polymer having a shape memory.
Such a shape memory polymer, which is amorphous or at least partially amorphous, is characterized by its so-called glass transition temperature in that the polymer undergoes a transition from a pliable, elastic state at temperatures higher than the glass transition temperature to a brittle glass-like state at temperatures lower than the glass transition temperature. Here, it could be noted that such a transition of a polymer is not exactly related to its glass transition temperature; if, for example, a polymer being in its glass-like state for a long period of time is exposed to a temperature just below its glass transition temperature, the polymer will undergo a transition to a more elastic state. For the purpose of the present invention, shape memory polymers have a further interesting property. When a shape memory polymer is formed into a particular shape at a higher temperature, the polymer will “remember” this shape, such that when the polymer is cooled and forced into another shape, the polymer will assume its original shape upon heating to a temperature above the state transition temperature. Examples of shape memory polymers may, for example, be found in the U.S. Pat. Nos. 6,388,043 and 6,160,084. In the international application WO 2004/110315 is further described how an implantable stent, which comprises first and second layers of at least partially amorphous polymers, can assume a first shape at a first temperature and second shape at a second temperature. The contents of these three documents are incorporated herein by reference.
Returning now to FIGS. 1 a and b , the retaining member 4 , which is made from a shape memory polymer, was originally formed into the large diameter shape illustrated in FIG. 1 b , and was then cooled and stretched to the smaller diameter configuration illustrated in FIG. 1 a . When the sealing device 1 , being at a temperature below the transition temperature, is positioned at a vessel wall, the outer member 3 can easily slide along the retaining member 4 . When the sealing device 1 , and in particular the retaining member 4 , subsequently is warmed to a temperature which is above the glass transition temperature of the retaining member 4 , the retaining member will return to its original shape, i.e. the large diameter configuration shown in FIG. 1 b . In this state, the diameter of the retaining member 4 corresponds to the diameter of the hole in the outer member 3 , which consequently is prevented from sliding along the retaining member 4 . In FIG. 1 a , the hole in the outer member 3 has been depicted as having a diameter that is considerably larger than the diameter of the retaining member 4 . This is merely for illustrative purposes: in practice, the diameter of the retaining member 4 would initially only be insignificantly smaller than the diameter of the hole in the outer member 3 . Correspondingly, without the presence of an outer member, a retaining member could expand to a diameter which is larger than the diameter of a hole in this outer member, to further increase the friction between the outer member and retaining member. It is also possible that the outer member 3 has been made from a shape memory polymer and formed in such a way that the hole in the outer member 3 contracts when the sealing device 1 is warmed to a temperature above the transition temperature. The transition temperature should be below the body temperature, i.e. below 37° C., and preferably well below the body temperature in order to have a fast transition from the state shown in FIG. 1 a to the state shown in FIG. 1 b . The latter is valid for all the embodiments of the present invention.
A second embodiment of a sealing device 11 according to the invention is illustrated in FIGS. 2 a and b . Like the first embodiment described in conjunction with FIGS. 1 a and b , the sealing device 11 comprises an inner member 12 , an outer member 13 , and a retaining member 14 . Here, the retaining member 14 is further provided with protrusions 15 made from a shape memory polymer. These protrusions 15 were originally formed into the radially protruding configuration shown in FIG. 2 b , and were then cooled and forced closer to the body of the retaining member 13 , as is shown in FIG. 2 a . When the sealing device 11 , being at a temperature below the transition temperature, is positioned at a vessel wall, the outer member 14 can easily slide along the retaining member 14 and over the protrusions 15 . When the sealing device 11 , and in particular the protrusions 15 , subsequently is warmed to a temperature which is above the glass transition temperature of the retaining member 14 , the protrusions 15 will return to their original configuration, i.e. to the protruding configuration shown in FIG. 2 b . In this configuration, the outer member 13 is effectively prevented from sliding along the retaining member 14 .
FIGS. 3 a and b illustrate a third embodiment of the present invention. Here, a sealing device 21 comprises an inner member 22 , an outer member 23 , and an at least partly hollow retaining member 24 , such as a suture, in the interior of which an expanding spiral element 25 has been placed. The spiral element 25 , which is made from a shape memory polymer, was originally formed into the large diameter configuration shown in FIG. 3 b , and was then cooled and compressed or stretched to the small diameter configuration shown in FIG. 3 a . When the sealing device 21 , being at a temperature below the transition temperature, is positioned at a vessel wall, the outer member 23 can easily slide along the retaining member 24 . When the sealing device 21 , and in particular the spiral element 25 , subsequently is warmed to a temperature which is above the glass transition temperature of the spiral element 25 , the spiral element will return to its original configuration, i.e. to the large diameter configuration shown in FIG. 3 b . In this configuration the friction acting between the outer member 23 and the retaining member 24 prevents the outer member 23 from sliding along the retaining member 24 .
The previously described embodiments of a sealing device according to the invention were primarily directed to the locking function between an outer member and a retaining member. A reliable locking function is prerequisite for a reliable sealing function of a sealing device. In a fourth embodiment of the invention, which is depicted in FIGS. 4 a and b , the memory properties of an inner member 32 and an outer member 33 are more directly directed to the sealing function of a sealing device 31 . Besides the inner member 32 and outer member 33 , the sealing device 31 comprises a retaining member 34 . The inner member 32 as well as the outer member 33 are made from a shape memory polymer, and were originally formed into the bulging configuration shown in FIG. 4 b . The inner and outer members 32 , 33 were then cooled and flattened to the flat configuration shown in FIG. 4 a . When the sealing device 31 , being at a temperature below the transition temperature, is positioned at a vessel wall 35 , the inner and outer members 32 , 33 come to a position where their inner sides are essentially parallel with the vessel wall 35 . When the sealing device 31 , and in particular the inner and outer members 32 , 33 , subsequently is warmed to a temperature which is above the glass transition temperature of the inner and outer members 32 , 33 , the inner and outer members 32 , 33 will return to their bulky configurations, i.e. to the configuration shown in FIG. 4 b . In this configuration, the concave sides of the inner and outer members 32 , 33 face the vessel wall 35 ; and due to the non-planar shapes of the inner and outer members, the vessel wall is tightly clamped between the inner and outer members 32 , 33 . In other words, the shape memory property of the polymer from which the inner and outer members 32 , 33 are made provides an extra amount of clamping force, which thereby adds to the sealing capacity of the sealing device 31 .
Although the present invention has been described with reference to specific embodiments, also shown in the appended drawings, it will be apparent for those skilled in the art that many variations and modifications can be done within the scope of the invention as described in the specification and defined with reference to the claims below. It should in particular be noted that the different shape memory parts of a sealing device according to the invention could be made from more than one shape memory polymer, which preferably is biodegradable (bioabsorbable), and the shape memory polymers could be provided as layers, as, for example, suggested in the above-referenced application WO 2004/110315. The invention is also applicable to the sealing of other types of holes or openings in the walls of bodily organs, such as atrial septal defects (ASD) or patent foramen oval (PFO).
|
The invention relates to a medical sealing device ( 1 ) for the sealing of a puncture hole in a vessel wall, and comprises an inner member ( 2 ), which is adapted to be positioned at an interior surface of the vessel wall, and an outer member ( 3 ), which is adapted to be positioned outside the vessel wall, the inner member ( 2 ) and the outer member ( 3 ) being held together by a retaining member ( 4 ), wherein at least one of said inner member ( 2 ), outer member ( 3 ) and retaining member ( 4 ) is made from at least one shape memory polymer.
| 0
|
BACKGROUND OF THE INVENTION
The invention relates to ejection devices for use in a production line.
This invention may be used with conveyers having a plurality of rows of articles and especially food articles.
It is well-known to use pivoting members in connection with conveyor belts. The Prior Art pivoting members for use with conveyor belts cannot be used with multiple rows which are closely spaced, without suffering sufficient downtime loses do to breaking of an individual one of the conveyer belts. Maintenance of and replacement of a single individual conveyer belt on a pivoting section in the Prior Art would require removal of the entire drive shaft, making necessary extensive disassembly and re-assembly operations where the individual belt is for example between other conveyer belts rather than on the end. This lack of accessability, in a practical sense, limits the number of rows of articles which can be handled by such a pivoting conveyor system. Also, since the Prior Art pivoting conveyor members are difficult to maintain when a belt breaks, they may be undesirable for use in a high production system where there is only limited storage for articles coming off the conveyor belts, and which articles cannot be processed during the maintenance time. Furthermore, the Prior Art pivoting conveyor belts do not provide for rapid replacement of an integral belt, but would require use of a spliced belt which is stretched around the rollers and then joined in place. Such spliced belts do not last as long as integral belts which have been formed as a continuous band.
The U.S. Pat. No. 3,404,775 to McClellan shows in FIG. 2 a linearly-movable arm 22 which causes pivoting of an arm 18 which in turn causes pivoting of a conveyor belt 25. Pivoting causes dropping of a brick between two adjacent conveyor belts, as seen in FIGS. 2 and 3. It is noteworthy from an inspection of FIGS. 3 and 4 that two different pivoting conveyor belt sections must be pivoted in order for a brick 51 to drop. This is a result of the parallel adjacent members 56, 58 and 60, 62, as well as members 57 and 59 which are adjacent to members 61 and 65. These pivoting conveyor belt segments can be actuated by electrical pneumatic, or other signals to drop selected bricks upon crosswise-moving belts to classify bricks according to color, finish, or other characteristics. However, this patent does not teach or suggest mounting a plurality of closely-spaced conveyor belt members for selective pivoting (or other movement) out of a conveyor belt path to permit dropping of selected articles, wherein the closely-spaced conveyor belts are driven in such a manner as to render any single one of the closely-spaced conveyor belts replaceable with a continuous band conveyor belt rather than a spliced conveyor belt.
The U.S. Pat. No. 4,426,074 to Fisher teaches a pivoting conveyor belt segment having an actuator 14, for clearing spoiled items from an overlapped stream of paper products. A three-flight conveyor belt transporting system is rocked bodily, so as to have an upper and a lower position so that a continuous stream of spoiled items can be transferred downwardly under the next flight to separate delivery. FIGS. 1 and 2 are illustrative, and show a sensor 17 such as a photoelectric cell together with a processing unit 18 capable of actuating a solenoid of valve 15, so as to drive cylinder 14. However, there is no teaching or suggestion of a plurality of commonly-driven conveyor belt segments which are selectively movable out of a conveying relationship and which are so connected with a drive means that any single belt can be replaced with a continuous belt without removing any other parts.
The U.S. Pat. No. 4,424,966 to Chandhoke teaches a cylinder 144 which causes pivoting of a conveyor belt segment 32 between rolls 46 and 54, between an upper conveying and a lower position. When the conveyor belt 32 is in the lower position, a member 134, 136, which is a rake, forms a bridge between the pulleys 46 and the T-shaped member 98 to support the books from the binder 12 on the upstream portion 30 of the conveyor 20. The articles so supported by the rake are thus in place ready to move the conveyor end portion 32 returns to its horizontal position. However, there is no teaching of a plurality of commonly-driven conveyor belt segments which are selectively movable out of a conveying relationship and which are so connected with a drive means that any single belt can be changed without removing any other parts, thereby permitting the use of continuous belts.
Other patents showing related types of conveying and diverting devices are shown in U.S. Pat. Nos. 4,166,525; 3,640,372; 4,499,988; 4,130,193; 3,354,613; 1,762,772; 828,296; and 2,675,118.
SUMMARY OF THE INVENTION
The invention is a selective diverting device for diverting an individual cookie from one conveyor belt path to another location. It is preferably used in combination with a sensing device, such as a weigher, optical sensor, color sensor, or the like, the sensor selecting out "rejected" cookies and actuating the diverting member.
The diverting member itself comes in three embodiments, all similar, and a fourth embodiment which is somewhat different. The first three embodiments include a pivotable conveyor-belt device which is automatically actuated (as by a piston or the like) to pivot out of the main conveyor belt path when a "reject" article is located thereon. In the fourth embodiment, the "reject" conveyor belt is a retractable device, not pivotable, and is for articles having a greater length than the spacing between two rollers (since relatively large gaps occur in this embodiment).
In a separate aspect of this invention, due to the need for a plurality of narrow diverting belts to operate on cookies from a single large conveyor belt, a drive means is used which forms a separate aspect of the invention to be searched. In this aspect of the invention a single long drive shaft has multiple gears, each gear engaging a driven gear on the diverting belts. This arrangement is necessary so that continuous, rather than spliced, conveyor belts can be stretched into place for maintenance and repair operations. Thus, there is a clearance between the drive shaft and the nearest portion of the conveyor belt, so that a new conveyor belt can be snapped over the rollers for replacement at any time, without removal of any of the other diverting belt parts.
In one embodiment of the present invention, a pneumatic cylinder is selectively actuatable to cause pivoting of a support member about the drive shaft. A drive shaft has a drive gear which is in driving relation to a driven gear, the driven gear being operatively attached to a roller for a belt. Other rollers are provided, as well as a tensioning roller for maintaining tension in the belt. Each of the other rollers completing the conveyor belt circuit are rotatably mounted upon the support plate. An end of the pneumatic cylinder is pivotably connected to the support member, and the other end of the pneumatic cylinder is pivotably connected to a fixed support. The end of the driven cylinder which supports the belt is open, as are the other rollers which support the belt, so that a conveyor belt can be removed or placed over the rollers without disassembly of any of the rollers or other parts. Thus, a continuous conveyer band such as a nylon belt, can be used for prolonging a period between required belt changes due to worn or broken bands. A new continuous belt can be used to replace a broken belt without disassembly of any other parts.
The diverting member is placed in bridging relationship between two conveyers belts, each conveyor belt having multiple rows and columns of articles thereon. In response to a sensed attribute of the articles such as overweight or underweight, color of the article, or sensed information regarding the shape and composition of the article, among other measurable attributes, an individual article can be ejected by pivoting motion of the selective diverting device away from the bridging relationship, so that the selected article passes in between the two stationary conveyor belts, whereupon the diverting member is returned to its bridging relationship.
In another embodiment of the invention, a tensioning roller is omitted, and instead of flat conveyor belts, round conveyor members having circular cross-sectional shapes, are used.
In another embodiment, the support member is not mounted about the drive shaft, but rather a slotted guide member is used which is fixed to a stationary support. In this embodiment, the bridging portion of the conveyor belt is an end of the conveyor belt which is curved about an end roller. The support plate rotatably supports the end roller as well as the driven roller, the support plate having a follower member attached thereto for following the slot of the slotted member. Another plate can be used to pivotably fix the drive roller to the driven roller during pivoting motion thereof. An actuating member such as a pneumatic cylinder can be used to position the end roller either in bridging relationship or in non-bridging relationship between two stationary conveyor belts. The actuating member causing linear movement of the support member and the driving gear attached about the drive shaft remains in contact with the driven gear throughout. A small amount of angular motion of the support plate occurs due to the motion of the driven gear relative to the drive gear. The conveyor belt support rollers, namely the end roller and the driven roller are rotatably mounted to the suport member such that the conveyer belt can be removed and replaced without disassembly of any other parts.
A computer or signal processor can be used in combination with any known type of sensor appropriate for the articles conveyed, in order to selectively actuate any one or ones of the diverting members to permit diversion of individual selected articles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a front elevational view of a diverting member used in the present invention;
FIG. 2 is a top elevational view of the diverting device according to the present invention;
FIG. 3 is a side view, partially in section, along line 3--3 of FIG. 1, showing two diverting members arranged as used;
FIG. 4 is a front elevational view of an alternative embodiment of a diverting device;
FIG. 5 is a side sectional view showing an alternative belt arrangement;
FIG. 6 is a front elevational view, partially in section, of another embodiment of the diverting member; and
FIG. 7 is a front elevation view of another embodiment of the diverting member.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the front elevational view of a diverting member 1. The diverting member 1 includes a support plate 20. The support plate 20 is closely rotatably mounted about a drive shaft 50. The support plate 20 is pivotally connected by a pin 13 to a collar 7. The collar 7 is supported by a shaft 8 and an air cylinder 9.
The air cylinder 9 in the preferred embodiment is a Clippard pneumatically-driven cylinder UDR-12 having a 1/4 inch bore and a 2-inch stroke. The air cylinder 9 is preferably double acting so as to provide a positive force for moving the shaft 8 in both directions. The air cylinder 9 is pinned at its lower end by a pin 14 to a support member 17 connected to a fixed support 18 represented schematically in FIG. 1. The air cylinder 9 has an upper air inlet 110 and a lower air inlet 12. Air flow is indicated schematically by arrow 22 and arrow 23 for respective inlets 110 and 12.
The diverting member 1 is in bridging relationship between a downstream conveyor belt 2 and an upstream conveyor belt 3. The conveyor belt 2 has a belt 19, and the conveyor belt 3 has a belt 21. Both of the belts 19, 21 move with a speed W as indicated by the arrows in FIG. 1; however, it is contemplated as being within the scope of the present invention that the conveyor belts 19 and 21 may move differing speeds, which differing speeds can be used to adjust the spacing between articles. It is also contemplated as being within the scope of the present invention that the conveyor belt 4 can move at different speeds than the belts 19 and 21, if desired. As seen in FIG. 1, an article 10, such as candy bar or other article, has passed from conveyor belt 21 and onto a conveyor belt 4 which is part of the diverting member 1.
The conveyor belt 4 is supported by a roller 11 and a roller 12, both of which are rotatably mounted for rotation about each respective roller axis, upon the plate 20. Additionally, a tensioning roller 13 is slidably and rotatably mounted for contact with the belt 4 by a spring member 15 which is fixably connected at its other end to a support block 16. The support 16 in turn is fixed to the plate 20. The tensioning roller 13 is not necessary and omission of a tensioning roller from any embodiment shown, or inclusion with any embodiment, is contemplated as being within the scope of the present invention.
A gear 6 is rotatably fixed about its axis to the plate 20, and is fixedly connected against relative rotation to a driven roller 5. Any alternative means of connection can also be used, such as reduction gearing, or other connecting means between the gear 6 and the roller 5. A drive gear 3 is in contact with the driven gear 6, the drive gear 3 being fixedly connected as by a pin, welding, or the like to a drive shaft 50. Thus, the drive gear 3 rotates relative to the plate 20 but gear 3 is fixed to the shaft 50 for rotation therewith.
While an air cylinder has been described in the preferred embodiment, any actuating device can be used instead, such as a solenoid, a magnetically-actuated device, or a mechanical device, or any other device capable of moving the device 1 between two positions. The air supply to either the top or the bottom air cylinder 9 is supplied from an air supply. Flow into or out of the port 110 and 12 is preferably valved by a solenoid-actuated valve or the like. An air cylinder 9 has been chosen in the preferred embodiment for maintainability and reliability, however any other actuating devices can be used in the present invention.
Further, while a plate 20 is shown, any support structure can be used instead, including curved, prismatic, or other shapes; and any forming means can be used for the member 20 or alternatives thereof, including but not limited to molding, casting, cutting, metalworking, or other forming means.
The support plate 20 is preferably made of strong, light-weight material such as aluminum, but it can also be made of steel, plastic, wood, or any other material sufficiently strong to support rollers and a conveyor belt. The rollers are preferably any conventional roller formed of wood, plastic, steel, aluminum, or the like and are mounted for rotation by bearing members. Such bearing members may include, for example, a low-friction material such as nylon or Telfon, ball bearings, journal bearings, or any other type of bearing known to those skilled in the bearing art. The belt 4 is preferably a flat urethane endless belt, such as those well-known in the art. However, any type of belt and belt material, including woven cloth, plastic, rubber, steel mesh or the like can be used with the present invention. Furthermore, while endless belts are preferred in the present invention for greater reliability and longer life, seamed belts can be used as well. Such seamed belts are usually made by splicing or by similar operations, and are generally inherently weaker and have a shorter life than endless belts which have no seams.
FIG. 1 shows the second position of the diverting member 1 in dotted outline. The gears 3 and 6 have meshing teeth (the teeth or omitted from the drawings for clarity). As seen by the dotted outline the gear 6 pivots to its position indicated by 6', which remains in toothed, engaging contact with the gear 3. The gear 3 does not rotate with the plate but rather with the shaft. Therefore, the gear 3 remains in driving relationship with the gear 6 throughout the pivoting operation. When the diverting member 1 is in its second, diverting position as indicated in dotted line, a subsequent article 10' passes between the conveyors 2 and 3 are indicated by the position shown in dotted outline in FIG. 1. The article 10' is indicated as having a velocity V, which is a combination of a forward velocity W and a downward component of velocity due to gravity.
The diverted article can fall downwardly into any type of receptacle. Furthermore, the diverted article 10' can fall upon a chute, another conveyor belt, or a shredder, among other devices, for further processing. All such further steps are contemplated as being within the scope of the present invention.
The diverting member 1 remains in its initial position shown in solid outline in FIG. 1 until a signal is received to divert an article 10', whereupon a diverting member 1 is moved to its second position as shown in dotted outline. After the article has been diverted, the air cylinder 9 is actuated to return the diverting member 1 to its first position as shown in solid outline.
FIG. 2 is a top elevational view of the diverting member 1, and the conveyor belts 2 and 3. Schematically indicated in FIG. 2 is a sensing device 24 for sensing each of the individual ones of the articles 10, and a signal processor 26 for processing signals received from the sensor 24. A controller 28 is also schematically indicated, for controlling a mechanism 30 which selectively actuates any one or ones of the air cylinders 9 to act upon respective diverting members 1. Also indicated schematically is an air supply 31 for supplying air to the air cylinders 9. Any air supply source, such as a storage tank, compresser, or the like can be used in the present invention.
The conveyor belts 2 and 3, as well as the diverting members 1, are shown as being broken way in dotted outline along a longitudinal centerline. The broken away portion indicates that an arbitrary number of additional members or additional width of conveyor belt can be used, as appropriate. Also, a lesser number of rows and a lesser number of diverting members, as well as a lesser width of conveyor belt, can be used. All such variations are contemplated as being within the scope of the present invention. In the preferred embodiment, twenty four diverting members are arranged to be driven simultaneously by a single shaft 50. Each diverting members 1 receives articles from a single row of articles from the conveyor belt 21. When an article 10 to be diverted is sensed by the sensing member 24, the signal processor 26, having received signals along the pathway 25, determines the appropriate time for actuating a diverting device 1, and also selects one of the diverting devices 1 to be actuated. More than one diverting member 1 can be actuated selectively simultaneously, depending upon the articles 10 arriving at the diverting devices 1. The signal processor 26 takes into account the belt speed W of the belt 21, the position of the sensed article 10 which is to be diverted, and computes the desire to time at which the particular diverting device 1 is to be actuated.
The signal processor 26 in the preferred embodiment is a computer. Instructions are preferably programmed into the computer, which preferably compares the sensed information about the articles 10 with predetermined "acceptable" range for the particular attribute sensed. For example, if color is sensed, a particular degree of browning, or a particular shade of color may be optimum, but there is ordinarily an acceptable range of browning, or of colors, such that outside the range, articles 10 are to be rejected. Additional sensors can also be employed, for example, weight, shape, composition, etc., which sensors also would send signals to the signal processor 26. Thus, any number of sensing devices can be used, such as an ultrasonic thickness measuring device, an infrared scanner, a television camera, a salinity meter, a magnetic sensor, or the like can all be used. Thus, any number of sensing devices can be employed, the signal processor 26 accepting signals from all of the sensors and diverting articles 10 if the individual article 10 to be diverted fails to fall within the predetermined range of values sensed by the sensing devices 24.
The signal processor 26 can preferably include a vision processor for comparing image information received from imaging devices such as television cameras or the like, and comparing the images to a number of predetermined acceptacle images, for determining whether or not to divert a particular article 10. The signal processor computers, based upon empirical data, theoretical equations, and other sensed inputs such as conveyor belt speeds of the belts 21 and 19, as well as any other conditions which are to be sensed, and sends its processed output signals (decisions) by pathway 27 to a controller 28.
Controller 28 can also be a computer, or it can be an analog controlled device. Furthermore the controller 28 can be a part of the signal processor 26 if desired. The controller 28 supplies signals and/or power to actuate individual ones of the diverting members 1 shown in FIG. 2. Such controllers are well-known in the art, and any controller for selectively actuating one of a plurality of actuatable devices can be used with the present invention. In the preferred embodiment, the controller supplies electrical power to solenoids which control air flow to the individual air inlets 110 and 12 of the cylinder 9.
While a preferred embodiment of actuator 9, controller 28, signal processor 26 and sensing devices 24 have been described and illustrated, the present invention is not limited thereto but encompasses any and all equivalent structures known to those skilled in the respective arts. The pathways 25, 27, and 29, as well as the air supply conduit 22, are schematically illustrated and would include any appropriate conduit for the device chosen. For example, the conduits 25, 27 and 29 are preferably electrical cables or cords where the sensing devices 24 have electrical outputs and where the signal processor 26 and the controller 28 have electrical operating elements. For an analog control system, however, a fluidic computer might be used, or analog control elements could be used as well.
FIG. 3 is a sectional side view of a diverting member 1 taken along the line 3--3 of FIG. 1. Also shown to the left in FIG. 3, in side elevational view partially broken away at the upper portion, is another diverting member 1, showing the nesting relationship of the adjacent diverting member 1 and also showing the clearance between an end of a belt-carrying roller 5 and the support plate 20 of the adjacent diverting member 1. Also shown broken way at each end is the drive shaft 50 which drives each of the respective gears 6 of the respective diverting members 1.
As seen in FIG. 3, the plate 20 has a collar portion 20 disposed about the shaft 50. In the preferred embodiment, a low-friction member 41, such as a nlyon sleeve or the like, is fixed in between the collar of the member 20 in the shaft 50 to permit relative rotation between the shaft 50 and the plate 20.
The plate 20 supports a shaft 51 which is fixed thereto, the shaft 51 rotatably supporting the roller 12. This is schematically indicated in FIG. 3, with a cross-section of the flat belt 4 being visable atop the roller 12 in FIG. 3. A portion of the belt 4, partially broken away at either end, is visible in FIG. 3 between roller 5 and 12. The roller 5 is mounted by bearings 46 to a shaft 44. An end member 45 retains the roller 5 in position along the shaft 44. A shaft 42 is connected to the shaft 44 as well as rotatably supporting the gear 6. The gear 6 meshes with the gear 3 which is pinned or welded to the shaft 50. Any means of attachment of the gear 3 may be used, such as keying, glueing, ultrasonic welding or the like, which are within the ambit of a skilled artisan.
The collar portion of the plate 20 serves to maintain the plate 20 against angular movement relative to the shaft except for rotational movement within a plane perpendicular to the axis of the shaft as indicated in FIG. 1. Thus, the plate 20 can rotate about the shaft 50 in a single plane between the two positions shown in FIG. 1 namely the solid position and a dotted-outline position.
The gear 3 is retained also by a collar 120 which prevents sliding movement along the shaft 50. There is a clearing between the top of the collar 120 and the belt 4 just above it as seen in FIG. 3. Thus, there is a clearance for replacing a belt 4, the clearance being between adjacent diverting members 1 as well as between the bottom of the roller 5 and the top of the collar portion of support member 20, as well as the top of the collar 120 as seen in FIG. 3. Thus, a belt can be placed around the rollers 11, 12, 13, and 5 without removal of any parts or elements of the diverting members 1, and does not require removal of the shaft 50. This is despite the very close spacing between adjacent diverting members 1 which is seen in FIG. 3. This close spacing of belts 4 atop the diverting members 1 is necessary where there are closely spaced articles arriving from the conveyor belt 21 (shown in FIG. 2).
The roller 12 is mounted in a similar manner to the rollers 11 and 13, which is shown in FIG. 3 as including a support shaft 52 which is rotatable relative to the roller 12, and a stop member 53 which retains the roller 12 on the shaft 52. The shaft 52 can be made of a low-friction material such as Teflon, nylon, or the like, or it may include ball bearings or other bearing surfaces such as a journal bearing.
Furthermore, the shaft 52 may be integral with the roller 12 and the shaft 51 then be made rotatable and journaled or otherwise made rotatable relative to the plate 20 within which it is received.
FIG. 4 is a front elevational view of another embodiment of an alternative diverting member 200. The diverting member 200 would be supported by a similar support plate 20 (not shown in FIG. 4 for clarity) and be actuated by a similar actuator 9. However, rather than the surface of a belt 61 being used to bridge the gap between adjacent conveyor belts 19 and 21, rather the curved end of a roller 60 having a belt thereacross is used. Here, no tensioning roller is used, although if desired a tensioning roller can be provided. In FIG. 4 there is seen an article 10 which is overlying the roller 63 and having a portion in the gap between the rollers 62 and 63. For this embodiment, the permissible range of articled sizes is indicated as follows. The smallest article has a length Y, and the longest article has a length X. Between the range of sizes (between the lengths X and Y), articles can be diverted by pivoting of the diverting member 200 to the position shown in dotted outline in FIG. 4. In the dotted outline position the diverting member 200 is no longer in bridging relationship, and the article 10 can fall in the gap between 62 and 63. When the article has been diverted, the diverting member 200 is returned to its bridging position shown in solid outline.
The belt 61 used with the diverting member 200 is preferably not a flat belt but rather a pair of round belts. FIG. 5 shows a cross-sectional view of the mounting of the round belts on roller 60. The round belts 60', 61' together support an article 10. Here, the article is preferrably an edible article such as a candy bar or a cookie or the like. However, any other article can be diverted by the diverting device 200, and the present invention is not limited to use with edible articles, candy bars, or cookies but encompasses all articles capable of being conveyed by any conveying means.
FIG. 6 is a front elevational view, partially in section, showing another embodiment of diverting member 1. Here also, a support plate 20 is used to maintain separation between rollers 75 and 76. A gear, hidden behind roller 76 but attached thereto for rotation therewith, is in engaging contact with gear 5 which is fixed for rotation with shaft 50. The shaft 50 is shown in section in FIG. 6, since the shaft 50 extends perpendicularly to the plane of the drawing for driving other diverting members. The diverting device 1 is in bridging relationship between a pair of rollers 72 and 73.
A pneumatic cylinder 9 is fixed to the plate 20, in pivoting relationship by a pin 14. The pneumatic cylinder 9 is also pinned at its other end by a pin 74, so that, upon change in the distance between 14 and 74, the diverting member 1 pivots to the position shown in dotted outline in FIG. 6, as does the position of the pneumatic cylinder 9. Thus, the belt 77 carried by the rollers 75 and 76 in FIG. 6, is in bridging relationship between the rollers 72 and 73. The belts associated with the respective rollers 72, 75 and 76, and 73 need not move at the same respective speeds, but rather each can have its own speed. A single selected speed W has been selected for convenience, where the spacing between the articles is not to be changed. However, with different belt speeds, the spacings between articles can be increased or decreased by appropriate adjustment of the speeds of the various conveying members.
The miscellaneous conventional elements such as bearings, and alike, can be those as shown in FIG. 3, or any other suitable bearing and other elements can be used, for example nylon bushings can be used for an anti-friction surface and the like. Again, the plate 20 extends about the shaft 50, so that it is relatively rotatable thereto. Also, the plate 20 portion passing about the shaft 50 is also relatively rotatable relative to the gear 5. Such arrangement can preferably be similar to that shown in FIG. 3, however any equivalant structure or alternatives which would be known to anyone having ordinary skill in the art, are contemplated as being within the scope of the present invention.
As seen in FIG. 6, in the solid-outline position the diverting member 1 is in bridging relationship and is capable of carrying articles from the conveyor belt supported by roller 73 and on to conveyor belt 77, once the articles pass to the conveyer belts supported by roller 72. In the dotted outline position of the diverting member 1, shown in FIG. 6, the diverting member 1 is no longer in bridging relationship between rollers 72 and 73, thereby permitting a selected article to pass between the rollers 72 and 73 and downward, rather than onto the conveyer belts supported by roller 72.
The pneumatic cylinder 9 is preferrably of the double acting type, having a positive forward thrust as well as positive reverse thrust, similar to the pneumatic cylinder shown in FIG. 1 which has an inlet passage 110 and an inlet passage 12 for passage of air. Also, as discussed with reference to the other embodiment, solenoids or other controls can be used to control the action of the cylinder 9, so as to control the position of the diverting member 1 between its solid-outline position and its dotted-outline position. Such solenoids are actuated either manually or by a controller 28 such is as shown in FIG. 2. However, any known control means for moving a divertng member from its solid-outline position to a dotted outline position is contemplated as being within the scope of the present invention. Such means might include electromagnetic, mechanical, pneumatic, manual, or the like actuating means.
FIG. 7 is a front elevational view of an alternative embodiment of the diverting member according to the present invention. Here, the diverting 600 has a roller 87 and belt 98 which bridges a gap between rollers 91 and 92. The belt 98 is preferably similar to belt 61' having a round cross-section, with grooves being formed in the roller 87 for receiving a pair of such belts 98 similar to that shown in FIG. 5.
Here, due to space limitations and the close spacing of the rollers 91 and 92 to the roller 87, relatively small articles can be selectively diverted. This is possible due to the very small gaps between the roller 87 and the roller 92, as well as between the roller 87 and the roller 91. Due to this close tolerance, the roller 87 must be retracted substantially downwardly, rather than being pivoted through an arc. Here, the supporting structures are somewhat different from the previous embodiments, however a similar actuating means 9 can be used on either the support plate 20 or the auxiliary support plate 420 discussed hereunder.
The support plate 20 pivotably supports rollers 87 and 5. No belt slack take-up roller is provided, although use of such take-up roller together with any other rollers desired is contemplated as being within the scope of the present invention. Also, the support plate 20 is not extended to encompass and surround the shaft 50, but rather terminates without encircling the shaft 50. A follower 80, which may be a fixed or rotatable member which is attached to the plate 20, is made and adapted to follow a slot 86. The slot 86 is formed in a guide plate 85, the guide plate 85 being fixed to a support which is stationary with respect to the parts shown. This support is indicated schematically in FIG. 7.
As seen in FIG. 7, the slot 86 serves to guide the motion of the plate 20 as the follower descends to its lower most position indicated in dotted outline in FIG. 7, and returns to its upper most position shown in solid outline in FIG. 7. The dotted outline position of the roller 87 indicates that a gap is left between the rollers 91 and 92 to permit diverting of articles 10 passing from conveyor belt 21.
Another support plate 420 passes about the shaft 50 and is pivotally connected, as by pinning, or the like, to the plate 20 at a location which is colinear with the axis of the roller 5. Thus, the plate 420 is pivotable about the shaft 50, and is moveable relative to the gear 3, and is pivotable relative to the plate 20. Furthermore, the plate 42 is pivotable relative to the gear 6 and relative to the roller 5. Thus, the plate 420 serves only to retain the gear 6 in contact with the gear 3 during movement of the gear 6 to its dotted outline position shown in FIG. 7. An actuator, such as actuator 9 shown in FIG. 1, can be provided and attached either to the plate 20 or to the plate 420, since the linkage as shown including slot 86, plate 20 and plate 420, permit movement of the plate 20 and associated rollers from the solid outline position to the dotted outline position. The cylinder 9 can be pinned to a fixed support at one end and pinned for pivoting either to the plate 20 or to the plate 420 as desired, and such positioning of an actuating member such as the cylinder 9 would be a conventional design expedient known to any one having ordinary skill in the art.
While round belts have been discussed as compared with flat belts, the use of either flat belts or round belts is a matter of choice in the present invention. Any conveyor belts or means may be used, including V-belts, round belts, or flat belts, perforated belts, woven belts, chain-mesh belts, and the like. Furthermore, any belt materials can be used. Such materials include steel mesh, Teflon-coated materials, nylon, urethane, rubber, or the like.
Any control system can be used to actuate selectively the actuating members which are used in the present invention. Any and all actuating members capable of moving the diverting member 1 from one position to another are contemplated as being within the scope of the present invention. Furthermore, any selectively controllable control devices are contemplated as being within the scope of the present invention, and such control devices can be as discussed with respect to the signal processor 7, controller 28, and control device 30. Furthermore, any type of sensors can be used in determining which articles are to be diverted.
Articles useable with the present invention include any food products, including candy bars, cookies, cakes, pies, breads, as well as non-food articles such as bricks, pages, boxes, electrical circuits, or any other articles capable of being selectively diverted from one conveying means to another.
Also, although supply conveyor belts have been used for supplying articles to the diverting members shown in the present invention, other members can be used as well, such as a flat surface from which articles are pushed by articles behind the pushed articles, such as an accumulator station, as well as a chute wherein articles slide along the chutes to the diverting members, as well as any other supply means capable of supplying articles to the diverting members 1. The same is also true of the diverting member 600, namely that any supply member can be used and not just the conveyor 21 shown in FIG. 27. Furthermore, any other conveying means can be used to receive articles conveyed by the diverting while the diverting member is in its bridging position, and not just the conveyor belt 19 of the figures. For example, a flat accumulator tray can be used or a sloping chute can be used permitting accumulated articles to slide therealong if such is desired. These and any other conveying means and devices can be used for supplying articles to the diverting members and for carrying articles away.
The improved selective diverting devices of the present invention are capable of achieving the above-enumerated advantages and results, and while preferred embodiments of the present invention have been disclosed, it will be understood that it is not limited thereto but may be otherwise embodied within the scope of the following claims.
|
The invention is a selective diverting device for diverting an individual cookie from one conveyor belt path to another location. It is preferably used in combination with a sensing device, such as a weigher, optical sensor, color sensor, or the like, the sensor selecting out "rejected" articles and actuating the diverting member.
The diverting member itself comes in three embodiments, all similar, and a fourth embodiment which is somewhat different. The first three embodiments include a pivotable conveyor-belt device which is automatically actuated (as by a piston or the like) to pivot out of the main conveyor belt path when a "reject" article is located thereon. In the fourth embodiment, the "reject" conveyor belt is a retractable device, not pivotable, and is for articles having a greater length than the spacing between two rollers (since relatively large gaps occur in this embodiment).
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. patent application Ser. No. 13/105,326, filed May 11, 2011, which is a continuation U.S. patent application Ser. No. 12/506,395, filed Jul. 21, 2009, which is a continuation of U.S. patent application Ser. No. 11/200,406, filed on Aug. 8, 2005, all of which are incorporated herein by reference in their entirety.
TECHNICAL FIELD
[0002] This invention relates to the searching and ranking of linked information sources.
BACKGROUND
[0003] Information Retrieval (IR) is concerned with locating desired elements of information among a large corpus. A search engine is a one example of an IR system that enables documents (usually but not necessarily limited to text) to be retrieved from a large corpus on the basis of their degree of relevance with respect to a compact query presented by a user. The order in which documents are retrieved or presented is the ranking created by the search engine: the highest ranked documents, with respect to the query, are returned or presented first. Search engine ranking may be affected by both query-dependent and query-independent criteria. Query-dependent criteria generally attempt to identify the degree to which a document is semantically related to the query. An example is the correspondence of word frequency distributions. Query-independent criteria often seek to identify the degree to which a document is generally “good”, e.g. authoritative, intelligible, not fraudulent or not deceptive. An example of a query-independent criterion is the score computed by the PageRank algorithm, or similar algorithms that examine the link structure of a corpus of documents.
[0004] As mentioned above, query-independent criteria can provide a way of measuring the authoritativeness of a specific information source. For example, the more information sources that point to a specific information source, the higher the search rating score the information source gets, and the more authoritative it is judged to be. In some instances, the search rating algorithm is recursive, meaning that a information source's search rating score is based not only on the number of information sources that reference the original information source, but also on the search rating scores of the referencing information sources. In other words, the search rating score of an information source is based on both the number and quality of the referencing information sources.
[0005] For some information sources, all of the content is under the control of a single agent. In such cases, the reputation of the agent can be directly correlated with the content of the information source. In other cases, however, control may be delegated among several agents, each controlling a partition of the information source. To the extent that these partitions can be identified, agent reputation can be calculated at the partition level.
[0006] In general, however, it is difficult to correlate content on an information source with the agents responsible for creating or publishing that content. For example, an individual author may contribute content to multiple information sources, content within a single information source may originate from multiple agents, or ownership and control of information sources may change over time. As another example, a single web page can contain content controlled by multiple agents, such as advertisements which appear alongside news articles.
SUMMARY
[0007] The present invention provides methods and apparatus, including computer program products, implementing techniques for searching and ranking linked information sources.
[0008] In one aspect, the techniques include receiving multiple content items from a corpus of content items; receiving digital signatures each made by one of multiple agents, each digital signature associating one of the agents with one or more of the content items; and assigning a score to a first agent of the multiple agents, wherein the score is based upon the content items associated with the first agent by the digital signatures.
[0009] Implementations of the invention can include one or more of the following features. The techniques may further include determining the validity of the digital signatures. If no digital signature associates an agent with a specific content item, the content item is associated with an owner of a location where the specific content is found and a score is assigned to the owner based on the specific content item. The content items associated with the first agent include a content item that contains a digital signature associating the first agent with the content item. The content items associated with the first agent include a content item that includes a link to a digital signature associating the first agent with the content item. The content items associated with the first agent include a content item that is a web site or a portion of the web site. A second agent is associated by a second digital signature with a second content item with which the first agent is associated, and the second agent makes an assertion about the content item. The first agent makes an assertion with a digital signature that the first agent is an author of the second content item. The second agent makes an assertion with the second digital signature that the second agent is a reviewer of the second content item. The second agent makes an assertion with the second digital signature that the second agent is an editor of the second content item. The second agent makes an assertion with the second digital signature that the second agent is a publisher of the second content item. Assigning a score to the first agent can include assigning the score based on unsigned content items that the first agent is associated with as an owner of one or more locations where the unsigned content items are found. Assigning a score to the first agent can include assigning the score based on one or more assertions made by one or more other agents about content items associated with the first agent. Assigning a score to the first agent can include assigning the score based on one or more assertions made by the first agent. The score is used in ordering results of a search of the corpus.
[0010] Particular embodiments of the invention can be implemented to realize one or more of the following advantages. The identity of individual agents responsible for content can be used to influence search ratings. The identity of agents can be reliably associated with content. The granularity of association can be smaller than an entire web page, so that agents can disassociate themselves from information appearing in proximity to information for which the agent is responsible. An agent can disclaim association with portions of content, such as advertising, that appear on the agent's web site. The same agent identity can be attached to content at multiple locations. Multiple agents can make contributions to a single web page where each agent is only associated to the content that the agent provided.
[0011] Query-independent rankings of content and authors can be calculated. A query-independent ranking can be, but need not be, calculated offline, prior to accepting a user query of the content, and then used to calculate a query-dependent ranking used for presentation of results. An algorithm used for calculating a query-independent ranking could also be used within the context of a specific query, with minimal modification, to calculate a ranking specific to that query. For example, the corpus can be limited to the query-relevant content.
[0012] Particular embodiments implement techniques for computing agent ranks on the basis of a corpus of content signed by those agents, where the corpus optionally contains explicit links among documents and signed content. The agent ranks can optionally also be calculated relative to search terms or categories of search terms. For example, search terms (or structured collections of search terms, i.e., queries) can be classified into topics, e.g., sports or medical specialties, and an agent can have a different rank with respect to each topic.
[0013] One implementation of the invention provides all of the above advantages.
[0014] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the invention will become apparent from the description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic representation of a web page.
[0016] FIG. 2 is a flow chart of a method for generating and managing the public and private keys necessary to generate signatures.
[0017] FIG. 3 illustrates a linked database.
[0018] Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0019] FIG. 1 shows a mock-up of a sample web page 100 . The web page 100 can include various content pieces, including main body text 105 , comments 110 , 115 , image 120 , and advertising 125 . Each of these content pieces can be created by a different agent. For example, in one implementation, the main body text 105 is created by the owner of the web page 100 , the comment 110 is authored by a first agent of the web page 100 , and comment 115 is authored by a second agent of the web page 100 . An agent is any individual or entity that either provides content pieces, edits existing content pieces, or reviews existing content pieces on a web page. An owner of a web page is the agent that has ultimate control over the web page, including control over all of the content pieces of the web page, including content pieces provided by other agents. Agents that are not owners generally have limited control over content pieces on the web page. For example, in one implementation, a non-owner agent can place a comment on the web page, but not edit or delete the comments of other agents that are included within the web page.
[0020] In an alternative implementation, the comment 110 is authored by the first agent of the web page 100 , and the comment 115 is authored by the owner of the web page 100 . The advertising 125 can be provided by a third-party advertising service, and the contents of the advertising may or may not be under the control of the owner of the web page 100 . In other words, even though the web page 100 may be owned by a single agent, it is possible for content pieces within the web page 100 to have been created or supplied by agents other than the owner of the web page 100 .
[0021] Each content piece can be signed with a digital signature, either directly by the agent or indirectly on behalf of the agent. The digital signature identifies the agent that actually created each content piece on the web page 100 . In one implementation, each individual content piece on a web page is signed separately. In an alternative implementation, one or more content pieces on a web page is signed while other content pieces on the same web page remain unsigned. In another implementation, a digest or hash of the content piece or content pieces can be generated, and the digest or hash of the content piece is signed. Any suitable protocol for creating and validating digital signatures can be used, e.g., XML Digital Signatures. Additional information about XML Digital Signatures may be found in the XML-Signature Syntax and Processing Recommendation of Feb. 12, 2002, available from the World Wide Web Consortium (W3C) at http://www.w3.org/TR/xmldsig-core/ and incorporated here by reference.
[0022] The agent signing each content piece can claim various roles relative to the content, e.g., author, publisher, editor, or reviewer. The signature provides evidence that a particular agent has asserted its role with respect to the signed content piece, as the agent has exclusive access to the private key used to sign the content piece. In one implementation, the digital signature can include within the scope of the content signed other metadata such as creation date, review score, or recommended keywords for search.
[0023] In one implementation, agents have the ability to sign a subset of a web page, and exclude content for which the agent does not claim any responsibility. For example, an agent can sign a document while excluding any ads which are being served alongside the document. Signatures can be applied to anything from an individual hyperlink to an entire document. Signatures can also be applied to text, images, audio, video, or any other digital content. The signature allows anyone to verify that the content that is signed has not been materially altered since the signature was generated.
[0024] Signatures can be portable or fixed to a particular web page or uniform resource locator (URL). For example, a syndicated columnist may wish to sign a column once upon creation, and have the signature follow the document wherever it is published. In other cases, the agent signing the content may wish to prevent their reputation from being used to draw traffic to sites they do not control. In either instance, the metadata associated with the digital signature can indicate whether or not the reputation associated with the signing agent is portable or not. For example, in one implementation, the signature is linked to the URL of the site where the content is located by including the URL as metadata within the signed content.
[0025] In one implementation, multiple agents can sign content on a single web page. For example, a message board or web log can allow each post to be signed by its respective author. In an alternative implementation, unsigned content pieces can be attributed to a synthetic agency identified by the host, site, or URL on which the content piece appears. In another implementation, a single agent that controls multiple websites can sign the content on each of the multiple website, indicating that the single agent is responsible for the content on all of the multiple websites.
[0026] Each digital signature is tied to the content piece that is signed. In one implementation, the digital signature can be appended to the content piece, or otherwise located in immediate proximity to the content piece. In another implementation, the content piece can contain a link to the digital signature, e.g., a uniform resource identifier (URI) identifying the digital signature. In yet another implementation, the digital signature is located in a central file or directory separate from the content piece, and some portion or all of the content piece covered by the digital signature is the target of a link from the central file or directory. In any of these implementations, the digital signature can be used to verify that the content piece has not been modified since the content piece was signed by the agent.
[0027] The digital signatures can be used to influence the ranking of web search results by indicating the agent responsible for a particular content piece. In one implementation, the reputation for an agent is expressed as a numerical score. A high reputational score indicates that the agent has an established positive reputation. The reputational scores of two or more agents can be compared, and the agent having the higher reputational score can be considered to be more authoritative. In an alternative implementation, multiple scores can be computed for different contexts. For example, an agent might have a first score for content that the agent has written, and a second score for content that the agent has reviewed. In another example, an agent that is responsible for an entertainment magazine could have a high reputation score for content related to celebrity news, but a low reputation score for content related to professional medical advice.
[0028] Assuming that a given agent has a high reputational score, representing an established reputation for authoring valuable content, then additional content authored and signed by that agent will be promoted relative to unsigned content or content from less reputable agents in search results. Similarly, if the signer has a large reputational score due to the agent having an established reputation for providing accurate reviews, the rank of the referenced content can be raised accordingly.
[0029] A high reputational score need not give an agent the ability to manipulate web search rankings In one implementation, reputational scores are relatively difficult to increase and relatively easy to decrease, creating a disincentive for an agent to place its reputation at risk by endorsing content inappropriately. Since the signatures of reputable agents can be used to promote the ranking of signed content in web search results, agents have a powerful incentive to establish and maintain a good reputational score.
[0030] In one implementation, an agent's reputation can be derived using a relative ranking algorithm, e.g., Google's PageRank as set forth in U.S. Pat. No. 6,285,999, based on the content bearing the agent's signature. Using such an algorithm, an agent's reputation can be determined from the extrinsic relationships between agents as well as content. Intuitively, an agent should have a higher reputational score, regardless of the content signed by the agent, if the content signed by the agent is frequently referenced by other agents or content. Not all references, however, are necessarily of equal significance. For example, a reference by another agent with a high reputational score is of greater significance than a reference by another agent with a low reputational score. Thus, the reputation of a particular agent, and therefore the reputational score assigned to the particular agent, should depend not just on the number of references to the content signed by the particular agent, but on the importance of the referring documents and other agents. This implies a recursive definition: the reputation of a particular agent is a function of the reputation of the content and agents which refer to it.
[0031] In this manner, the reputation of a particular agent can be calculated by an iterative procedure on a linked database. A linked database (i.e. any database of documents containing mutual citations, such as the world wide web or other hypermedia archive, a dictionary or thesaurus, and a database of academic articles, patents, or court cases) can be represented as a directed graph of N nodes, where each node corresponds to an agent along with all of the content pieces associated with that agent, and where the directed connections between nodes correspond to links from a content piece of one agent to a content piece of another agent. A given node has a set of forward links that connect it to children nodes, and a set of backward links that connect it to parent nodes.
[0032] FIG. 3 illustrates a linked database 300 . A first agent 310 is associated with content pieces 312 , 314 , a second agent 320 is associated with content pieces 322 , 324 , and a third agent is associated with content piece 332 . Content piece 312 associated with the first agent 310 is linked ( 350 ) to content piece 322 associated with the second agent 320 , and content piece 324 associated with the second agent 320 is linked ( 352 ) to content piece 332 associated with the third agent 330 . Content piece 314 associated with the first agent 310 is linked ( 354 ) to content piece 332 associated with the third agent 330 , in addition to content piece 332 being linked ( 356 ) back to content piece 314 . In this implementation, the rank of a particular agent A, r(A), is calculated as follows:
[0000]
r
(
A
)
=
α
N
+
(
1
-
α
)
(
r
(
B
1
)
B
1
+
…
+
r
(
B
n
)
B
n
)
,
[0000] where B 1 , . . . , B n are the agents that link to A, r(B 1 ), . . . , r(B n ) are their ranks, |B 1 |, . . . , |B n | are the number of forward links in content signed by the agent, α is a constant in the interval [0,1], and N is the total number of agents in the database. The constant α is interpreted as the probability that a user will jump randomly to any content piece instead of following a forward link.
[0033] In an alternative implementation, a seed group of trusted agents can be pre-selected, and the agents within this seed group can endorse other content. Agents whose content receives consistently strong endorsements can gain reputation. In either implementation, the agent's reputation ultimately depends on the quality of the content which they sign.
[0034] In another implementation, a set of trusted signing authorities can make additional assertions such as establishing the time when content was signed. This would allow priority to be determined if two agents attempted to sign similar content.
[0035] The use of digital signatures permits the reputation system to link reputations with individual agents, and adjust the relative rankings based on all of the content each agent chooses to associate itself with, no matter the location of the content. For example, the content can be located across multiple websites, or mixed with the content of other agents on a single website. In another implementation, the content can include any sort of digital content, e.g., e-mail, CD-ROMs, or DVDs, and the content need not be located on the Internet. In addition, although the use of digital signatures permits signed content to be associated with a specific agent, it is not necessary to know the actual identity of the agent. Although each agent uses a private key unique to the agent to create each signature, no personal information about the agent is necessary for the signature to be created or for the signature to be used by others. In one implementation, the agent can revoke or otherwise invalidate the private key if the private key is compromised. Once the private key is revoked, the signatures created using the revoked private key will not be accepted as valid, and will not be used to link the agent with the content signed with the revoked private key.
[0036] FIG. 2 shows the use of a content authoring tool to generate and manage the public and private keys necessary to generate signatures. The content authoring tool receives one or more content pieces from an agent (step 210 ). The content pieces can include text, images, audio, video, or any other static digital content. The content pieces can represent an entire web site, an individual web page, or individual components of a web page. The content authoring tool then receives login credentials or other identifying information from the agent (step 220 ). The login credentials or other identifying information uniquely identify the agent. In one implementation, personal information can be associated with the login credentials or other identifying information, e.g., billing information. In an alternative implementation, no personal information is associated with the login credentials or other identifying information.
[0037] Next, the content authoring tool determines if the agent already has a public/private key pair for generating digital signatures (step 230 ). If the agent does not have a public/private key pair, a key pair is generated for use by the agent (step 240 ). In one implementation, the key pair is generated by an authentication service upon the request of the content authoring tool. In either case, the private key associated with the agent is used to create a digital signature for each of the content pieces (step 250 ). In one implementation, various metadata can be associated with the digital signature, such as a timestamp indicating the time and date that the digital signature was created, keywords relating to the content piece, or the URL of the website where the content piece is located. In one implementation, the metadata is appended to the content piece, and the content piece containing the metadata is digitally signed.
[0038] In one implementation, the content authoring tool can also be used to determine if the signature associated with a content piece is valid, and identify the agent that signed the content piece in question. Alternatively, any interested entity can use the public key portion of the public/private key pair to determine if the signature associated with a content piece is valid, and identify the agent that signed the content piece in question.
[0039] In another implementation, the content authoring tool can be used by an agent acting in an editorial or reviewing role to digitally sign a content piece as having been edited or reviewed. The process is similar to that shown in FIG. 2 and described above, with the addition that the digital signature created for each content piece includes metadata indicating that the agent edited or reviewed the digitally signed content piece. In one implementation, the metadata can also include a listing of edits performed or review score.
[0040] Embodiments of the invention and all of the functional operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structural means disclosed in this specification and structural equivalents thereof, or in combinations of them. Embodiments of the invention can be implemented as one or more computer program products, i.e., one or more computer programs tangibly embodied in an information carrier, e.g., in a machine-readable storage device or in a machine-readable propagated electromagnetic signal, for execution by, or to control the operation of, data processing apparatus, e.g., a programmable processor, a computer, or multiple processors or computers. A computer program (also known as a program, software, software application, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file. A program can be stored in a portion of a file that holds other programs or data, in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers at one site or distributed across multiple sites and interconnected by a communication network. The processes and logic flows described in this specification can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).
[0041] Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Moreover, a computer can be embedded in another device, e.g., a mobile telephone, a personal digital assistant (PDA), a mobile audio player, a Global Positioning System (GPS) receiver, to name just a few. Information carriers suitable for embodying computer program instructions and data include all forms of non volatile memory, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.
[0042] To provide for interaction with a user, embodiments of the invention can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor, for displaying information to the user and a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input.
[0043] Embodiments of the invention can be implemented in a computing system that includes a back end component, e.g., as a data server, or that includes a middleware component, e.g., an application server, or that includes a front end component, e.g., a client computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the invention, or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication, e.g., a communication network.
[0044] Examples of communication networks include a local area network (“LAN”) and a wide area network (“WAN”), e.g., the Internet.
[0045] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other.
[0046] Particular embodiments of the invention have been described. Other embodiments are within the scope of the following claims. For example, actions recited in the method claims can be performed in different orders and still achieve desirable results.
|
The present invention provides methods and apparatus, including computer program products, implementing techniques for searching and ranking linked information sources. The techniques include receiving multiple content items from a corpus of content items; receiving digital signatures each made by one of multiple agents, each digital signature associating one of the agents with one or more of the content items; and assigning a score to a first agent of the multiple agents, wherein the score is based upon the content items associated with the first agent by the digital signatures.
| 6
|
BACKGROUND OF THE INVENTION
The present invention relates to communication switching circuitry, and more specifically to a multi-stage analog bi-directional selector.
Multiplexers and de-multiplexers perform data path selection, but do not support asynchronous bi-directional communication.
Analog switches control bi-directional communication, but do not support data path selection. They also have input impedances which are too high (about 200 ohms maximum). This impedance requires a proportional increase in the voltage of the circuit which drives such a switch.
Presently, there are no low impedance devices which combine the data path selection of a multiplexer with the asynchronous bi-directional communication of an analog switch. Such a combination would be desirable, particularly for passing bi-directional TTL logic signals on a wire-or bus typical of what is found in the PC-AT keyboard, namely clock and data signals. Thus, two keyboards may be more easily connected to a single keyboard controller 49 within a computer. The computer may then choose which keyboard to communicate with.
Another application for this invention is in keyboard wedge devices, in which communication with the wedged device would occur through the keyboard's communication interface. The invention would be used in the keyboard to control placement of data from the wedged device onto the keyboard's communication channel.
Therefore, it would be desirable to provide a multi-stage analog bi-directional selector with low impedance and with low cost.
SUMMARY OF THE INVENTION
In accordance with the teachings of the present invention, a multi-stage analog bi-directional selector is provided.
The multi-stage analog bi-directional selector includes a plurality of analog switches including first and second bi-polar transistors coupled together at first and second connection points, a primary channel coupled to the first connection points, a plurality of data channels coupled to the second connection points, and an address circuit which causes a single one of the analog switches to form a bi-directional analog data connection between a corresponding single one of the data channels and the primary channel.
It is accordingly an object of the present invention to provide a multi-stage analog bi-directional selector.
It is another object of the present invention to provide a multi-stage analog bi-directional selector that has a low impedance.
It is another object of the present invention to provide a multi-stage analog bi-directional selector that is low in cost.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from the subsequent description of the preferred embodiments and the appended claims, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram of the multi-stage analog bi-directional selector;
FIG. 2 is a circuit diagram of a two-stage analog bi-directional selector within a computer system including first and second keyboards; and
FIG. 3 is a circuit diagram of a four-stage analog bi-directional selector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to FIG. 1, multi-stage analog bi-directional selector circuit 10 includes N-stage selector 12 and addressing logic 14.
N-stage selector 12 provides bi-directional analog communication between a primary channel 16 and one of a number N of data channels 18 N .
Addressing logic 14 determines which one of the data channels 18 N is connected to the primary channel 16 through N-stage selector 12. Addressing logic 14 includes address input 17.
The relationship between the number of channels N and the number of address bits B required may be defined by the equation
N<2.sup.B
For example, two address bits B will support up to four data channels.
Referring now to FIG. 2, a two-stage version of multi-stage analog bi-directional selector 10 is shown.
Two-stage selector 20 primarily includes two analog switches 22 and 24 which control bi-directional flow of TTL signals between keyboards 46 and 47 and a keyboard controller 49 within computer 48.
Switch 22 includes bi-polar transistors 26 and 28 in which the collector of one is connected to the emitter of the other. Connection 34 is coupled to computer 48 through primary channel 16, while connection 36 is connected to keyboard 47 through data channel 18 2 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 1 , R 2 , and R 3 .
Similarly, switch 24 includes bi-polar transistors 30 and 32 in which the collector of one is connected to the emitter of the other. Connection 38 is coupled to computer 48 primary channel 16, while connection 40 is connected to keyboard 46 through data channel 18 1 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 4 , R 5 , and R 6 .
A nominal value for resistors R 1 , R 2 , R 4 , and R 5 , is 10K ohms. A nominal value for resistors R 3 and R 6 is 4.7K ohms.
In both switches 22 and 24, bi-polar transistors are employed because they require only a nominal bias voltage V cc of five volts. Bi-polar transistors 26, 28, 30, and 32 have a model number of 2N3904.
Field effect transistors (FETs) are not employed because they present many challenges that would ultimately increase the cost of selector 10 to solve them. N-type FETs are less expensive than P-type and also offer lower resistance than corresponding P-types. However, n-type FETs are still relatively expensive and require a more expensive control circuit since they require voltage in excess of five volts (typically a V cc of 7 to 10 volts) to assure the minimum turn-on resistance.
All FETs have an intrinsic diode that provides a signal path in one direction through the diode, even though the FET is off. To prevent the diode path operation, it is necessary to connect two FETs in series such that the intrinsic diodes face opposite directions and hence do not provide a conduction path in either direction. Using two FETs connected like this works well, allowing the FET's on state to control the connection of the bi-directional signal path. However, using two FETs in series doubles the channel resistance so that lower channel resistance devices must be selected to limit voltage drop across the FET switch.
Bipolar transistors are typically almost half the cost of a corresponding FET, and do not require a high voltage supply to control them. Furthermore, bipolar transistors contain no intrinsic diode so they can be connected in parallel, with one device offering a conduction path for each polarity of signal. If the bipolar devices are driven to saturation in the "on" state, there is a predictable voltage drop of typically less than 0.2 volts.
An important advantage associated with the design of selector 10 is that the variation of pull-up resistors from different keyboard vendors does not materially affect the operation of the selector 10, since the voltage drop can be predicted. This is unlike the FET solution in which the channel resistance of both devices is added and the current supplied by the keyboard pull-up resistor causes a voltage drop that is predictable, but varies widely with different keyboards.
Since bipolar devices are involved, the control impedance is lower than a FET, however in this circuit, the control voltage is relatively high, because the β of the transistor multiplies the control current supplied by the on control circuit. Hence a relatively small control current (0.1 ma) can control a fairly large signal current (10 ma with a β of 100).
Addressing logic 14 includes two inverters 42 and 44 which determine which of data channels 18 1 and 18 2 is connected to computer 48 through primary channel 16. The keyboard controller 49 within computer 48 determines which of keyboards 46 and 47 is connected by producing an address input signal at address input 17.
Operation requires only a single-digit address. When address input 17 is high, inverter 42 produces a low output which causes transistors 26 and 28 of switch 22 to turn off and data channel 18 2 to be deselected. Inverter 44 produces a high output which causes transistors 30 and 32 of switch 24 to turn on and data channel 18 1 to be selected.
Similarly, when address input 17 is low, inverter 42 produces a high output which causes transistors 26 and 28 of switch 22 to turn on and data channel 18 2 to be selected. Inverter 44 produces a low output which causes transistors 30 and 32 of switch 24 to turn off and data channel 18 1 to be deselected.
Referring now to FIG. 3, a four-stage version of multi-stage analog bi-directional selector 10 is shown.
Four-stage selector 50 primarily includes four analog switches 52, 54, 56, and 58. Switch 52 includes bi-polar transistors 60 and 62 in which the collector of one is connected to the emitter of the other. Connection 76 is coupled to primary channel 16, while connection 78 is connected to data channel 18 4 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 7 , R 8 , and R 9 .
Switch 54 includes bi-polar transistors 64 and 66 in which the collector of one is connected to the emitter of the other. Connection 80 is coupled to primary channel 16, while connection 82 is connected to data channel 18 3 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 10 , R 11 , and R 12 .
Switch 56 includes bi-polar transistors 68 and 70 in which the collector of one is connected to the emitter of the other. Connection 84 is coupled to primary channel 16, while connection 86 is connected to data channel 18 2 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 13 , R 14 , and R 15 .
Finally, switch 58 includes bi-polar transistors 72 and 74 in which the collector of one is connected to the emitter of the other. Connection 88 is coupled to primary channel 16, while connection 90 is connected to data channel 18 1 . The base of each transistor is connected to a bias voltage V cc through pull-up resistors R 16 , R 17 , and R 18 .
Similar to the two-stage embodiment of FIG. 2, bi-polar transistors are employed because they require only a nominal bias voltage V cc of five volts.
A nominal value for resistors R 7 , R 8 , R 10 , R 11 , R 13 , R 14 , R 16 , and R 17 is 10K ohms. A nominal value for resistors R 9 , R 12 , R 15 , and R 18 is 4.7K ohms.
Addressing logic 14 includes two inverters 100 and 102 and four AND gates which determine which of data channels 18 1 , 18 2 , 18 3 , or 18 4 is connected to primary channel 16.
Operation requires a two-digit address and is illustrated by Table I:
TABLE I______________________________________Address 17A Address 17B Data Channel______________________________________Low Low 18.sub.1Low High 18.sub.2High Low 18.sub.3High High 18.sub.4______________________________________
Although the present invention has been described with particular reference to certain preferred embodiments thereof, variations and modifications of the present invention can be effected within the spirit and scope of the following claims.
|
A multi-stage analog bi-directional selector which has a low input impedance and cost. The multi-stage analog bi-directional selector includes a plurality of analog switches including first and second bi-polar transistors coupled together at first and second connection points, a primary channel coupled to the first connection points, a plurality of data channels coupled to the second connection points, and an address circuit which causes a single one of the analog switches to form a bi-directional analog data connection between a corresponding single one of the data channels and the primary channel.
| 6
|
BACKGROUND OF THE INVENTION
Large-scale production of salmon and trout fry in hatcheries has been carried out in essentially the same manner for over a century, and the basic procedures and components have changed little. In recent years, it has become increasingly apparent that although the survival of eggs to the fry stage is much better when the eggs are incubated in hatcheries than in nature, the quality of the hatchery fry is often poor. The low quality of the fry is not as significant in species protected and reared in the hatchery for a few weeks or months (such as chinook and coho salmon), but it may be a critical factor in species released to the wild as fry (such as pink and chum salmon). In recent years, efforts have been made by many experimenters to develop incubation systems that would produce higher quality fry at less cost and at remote sites or sites inaccessible during winter.
Gravel is the natural substrate for incubating salmon eggs and alevins. Although eggs can be incubated successfully in trays or other types of containers with smooth substrates, alevins tend to be more active on smooth substrate than on gravel. This increased activity leads to premature swimming and contributes to poor conversion of yolk to body tissue, resulting in undersized and frequently abnormal fry. New types of hatchery systems, called gravel incubators, can avoid these problems. Gravel incubators do work, but because of the high cost of labor, materials, and transportation in remote areas, e.g. Alaska, a system is needed that requires a minimum of lightweight material and can be transported by air at relatively low expense.
SUMMARY OF THE INVENTION
Each incubator unit consists of two sections--a top or upper section which nests into a bottom or lower section. Incubators can be operated in stacks or singly. The extended lower sides of the bottom section of each unit hold the nest unit in place when they are stacked.
Each section of the incubator contains a removable screen-type egg tray which can be charged with green eggs and inserted or removed while the incubators are in operation. Water is directed into an upper head chamber of the top section in each stack and flows by gravity through all the units below.
Water enters the upper head chamber and flows under an upper baffle. Some of the water then flows horizontally through a rugose substrate on the base of the section. A portion of the water upwells through the egg trays and then flows horizontally over the eggs. All the water flows in a thin sheet over an overflow lip and drops down to a head chamber of the bottom section. The water then goes under a baffle and flows as described above. The water then flows over an overflow lip of the lower section and is discharged to the head chamber of the unit below, if any.
The incubators are inspected periodically to see whether the eggs have hatched and the alevins fallen through the mesh of the egg trays to the substrate below. After the alevins have fallen through the tray an access door is opened, and the egg trays are removed by pulling the pair of cords attached to the sides of the tray. If desired, a fine mesh cover screen can be inserted in place of the egg tray at this time to prevent migration of the alevins.
A parallel-rod fry separator is attached to the downstream face of the overflow lip just before fry are expected to migrate. The fry separator allows the migrating fry to enter a fry collector rather than pass on into lower sections of the incubator. Most of the water passing the overflow lip falls through the parallel rods into the lower head chamber and the fry slide down the rods into the fry collector. When the fry separator is placed in the unit, a small flow of water is started into the fry collector of the uppermost section in the stack. This water builds up to the top of a standpipe in the fry collector and then overflows to the fry collector of the next lower unit. The water in the fry collector cushions the fry's fall off the parallelrod fry separator. The emerging fry in each stack of incubators accumulate in the lowest unit and are collected. If it is desired to collect the fry from any individual tray, this can be accomplished by a suitable arrangement of equipment.
It is an object of the present invention to provide an improved fish incubator means having a readily removable perforated or meshed egg tray located above a trough containing a rugose layer, a stream of water flowing over and through the egg tray and trough, wherein the alevins fall through the opening in the egg tray into the rugose layer, and wherein the fry migrate out of the layer and are separated and recovered.
It is a further object of the invention to enclose the fish incubator set forth above in a light tight compartment with hatch openings for interior access and having light shielded air ventilation means.
It is a further object of this invention to enclose the egg tray and trough set forth above in a container open at the top and bottom and adapted to be vertically nested into similar egg tray trough and container combinations to form a set and having water conduits arranged so that the water from one combination flows into the lower one, and having an upper cover and a lower base to close off the top and bottom of the egg tray, trough and container combinations.
Further objects will become apparent from the specification and claims set forth below.
THE DRAWING
FIG. 1 is an expanded isometric view of one embodiment of the incubator, partly in section, and showing the internal structure;
FIG. 2 shows the details of the fry screen;
FIG. 3 is a plan view of the egg tray;
FIG. 4 is a transverse sectional view of the housing section showing details of the egg tray support;
FIG. 5 is a detail plan view of the door;
FIG. 6 is a section of the door taken along line 6--6 of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment shown in FIG. 1, the cover section of the incubator is indicated generally by reference numeral 100. The cover consists of a top 100a, two ends 101 and 102 and two sides 103 and 104. An opening 105 is provided near one end of top 100a. A transverse baffle 106 is mounted between sides 103 and 104 beneath the opening, as shown in FIG. 1. Fastened to the bottom of the 106 to sides 103 and 104 and end 101 is flat base member 107. It will be seen that members 101, 103, 104, 106 and 107 together form a trough. A drain opening 108 is provided in 107, near end 101, and a water supply pipe source 109 is located above the trough, whereby water can enter the trough and flow out through the drain.
Located behind the trough is a spillway consisting of a transverse cross member 109a at the inner end of opening 105 and fastened to top 100a and sides 103 and 104. Secured to the bottom portion of 109a and sides 103 and 104 is a flat bottom member 110. A cross member 111 may be attached to the end of 110 as shown in the drawing, to serve as a lip. A baffle member 112a of relatively low height is mounted transversely on 110. A water supply source is located directly above the spillway defined by 109a and 110. It is seen that a channel is provided for water flow between 107 and 110, and while the depths of baffle 106 and 109a may vary considerably, the dimensions must be selected to provide an adequate channel for water flow.
Beneath the cover section 100 is located the housing section, generally designated by reference numberal 200. Said housing section consists of an open box having end sections 201 and 202 and sides 203 and 204. The inner dimensions of the housing section are such that cover section 100 fits into the top part of 200 snugly and without binding.
A trough unit 205 is located within approximately the mid depth portion of the housing unit and consists of a flat base portion 206 and end portions 207 and 208. Elements 207 and 208 are fastened to base 206 at the ends thereof and all of these elements are attached to sides 203 and 204 whereby a watertight structure is obtained. Elements 207 and 208 are spaced from 201 and 202 to provide a passageway for water flow, and the upper end of 208 is rounded as shown.
A transverse baffle 209 extends between sides 203 and 204 and is spaced from 207 to define a water passage 209a which is located directly below lip 111, so that water flowing over the said lip will fall through passageway 209a. The upper edge of 209 is at the same height as end 207, while the bottom of 209 is located above 206 a distance sufficient to accomodate a rugose substrate as will be described hereinafter, and to allow adequate water flow. Passageway 219, defined by elements 201 and 207, is in line vertically with drain 108. Located within trough 205 between end 208 and baffle 209 is an egg tray or screen 210. As best shown in FIG. 3, the egg tray or screen consists of a framework having sides 211,211 and end pieces 212,212 and a meshed screening 213. Attached to the sides 211 at one end thereof are pull tapes or cords 214,214. As shown in FIG. 4, the egg tray rests on tracks 215.
To enable removal of an egg tray without disturbing the assemblage of sections, a hinged door is provided at one end of housing section 200. As shown in FIG. 1, end section 201 has a rectangular opening of a width sufficient to pass egg tray 210 therethrough. Mounted on this end section is a rectangular door 216 hinged at the top by means of hinge 217 and offset strip 218 (FIGS. 5 and 6). Door 216 has a series of holes 218a drilled through for ventilation. A light baffle consisting of elements 221 and 222 is provided to prevent light from entering through holes 218a. To remove the egg tray, door 216 is opened, the pull cords 214 on the tray are grasped and the tray is then pulled out.
Resting on the base 206 of trough 205 is a rugose layer 220. Conveniently this may consist of vertical grasslike strands with spaces between the strands sufficient for accomodating the fry stages. The rugose plastic product sold under the trademark Astro Turf (Type CH-4, Monsanto Company, St. Louis, Mo.) is a suitable material, and is modified for use herein by removing the cloth backing present and about one half of the grasslike turfs. A distance between strands of from 1 to 3 fry diameter has been found satisfactory, although it is apparent that this range can be varied due to the flexibility of said strands. However, if desired, screened gravel may be employed although this suffers from the disadvantages of increased weight and labor handling costs. Water entering passageway 209a passes under baffle 209 and flows through and over the rugose layer 220, and upwells through and flows over egg tray 210, overflowing at end member 208.
Beneath the housing section 200 is located insert section 300. This consists of end sections 301 and 302, sides 303 and 304 and bottom 305. The length and width of insert section 300 are selected to fit snugly within the bottom of the housing section 200, without binding. Extending transversely across bottom 305 is a slot 306. At the front and back edges of said slot are vertical baffles 307 and 308 extending from sides 303 and 304 as shown in the Figure, baffle 307 is higher than baffle 308. It will be seen that elements 301, 305 and 308 define a trough 309, and a drain means 310 is provided at the bottom thereof. Said trough is located directly under drain 108 of the cover section, so that water passing through 108 will fall through passageway 219 in the housing section into trough 309.
At the other end of the insert section is located a transverse baffle 311. This is spaced from end 302 to define a water passageway 312 which is located beneath end 208 of trough 205, so that water overflowing 208 will fall through passageway 312. The upper edges of 311 and 302 are in the same plane while those of 301 and 307 are somewhat lower.
Located within the insert section between baffles 307 and 311 is essentially an egg tray 313 identical to egg tray 210 and mounted in a similar manner, so that no further description is necessary. Similarly, a rugose layer 314 essentially identical to layer 220 rests on the bottom 305 between end 302 and baffle 307.
In a manner similar to that described in connection with the housing section, water entering passageway 312 of the insert section as the overflow from the housing section, flows through and over rugose layer 314 and upwells and flows over egg tray 313, spills over baffle 307 and passes out through slot 306. Shown mounted on 317 is fry separator 315, which will be discussed in more detail below.
The cover section, housing section and insert section described above, fit together to form an incubator unit, and the additional housing and insert sections may be added to form an incubator stack. A base section 400 having the length and width of the housing section is placed over the lowest or bottom insert section. This contains a suitable opening 401 for leading the water flowing from 310 and through 306 to a fry collection tank.
In operation, the upper housing section is inspected periodically to see whether the eggs have hatched and the alevins have fallen through the screen of the egg tray to the rugose substrate below. After the alevins have fallen through the tray, the access door 216 is opened and the egg trays removed. If desired, a fine mesh cover screen can be inserted in place of the egg tray at this stage. This will prevent migration of the fry alevins from the rugose. Within the rugose layer, the alevins continue their development to the fry stage.
Just before the fry are expected to migrate, a fry separator 315 is mounted on baffles 307 and 308. As shown in the detail given in FIG. 2, the separator consists of two support strips 317 and 318 with a number of rods glued or otherwise attached to them. The rods rest in a slot cut in baffle 307 and also rest on the top of baffle 308. The strips 317 and 318 are spaced to be adjacent the inner faces of baffles 307 and 308 when the separator 315 is in place. Thus, the fry separator 315 can readily be inserted on and removed from the baffles 307 and 308.
Since the egg trays have been removed at this stage, the fry readily pass along with the stream of water in migrating from the rugose layer. In the housing section, from rugose layer 220, the fry are carried over 208 and enter the lower rugose layer 314. Then, together with fry which had been hatched in insert section 300, they are carried with the water stream over baffle 307. The fry slide down the separator 315 and fall into trough 309 which contains a depth of water obtained from water supply 109 through drain 108 and passageway 219. The fry may be collected after the travel by opening through trough 309 and passing through pipe 310, and fall through the hole in base unit 400.
The invention described above has many advantages over the incubators employed heretofore. Removal of the trays of unhatched eggs without admitting light or having to dismantle the incubator or disturbing the fry by excessive movement reduces the tendency for premature emergence, cuts down on fungus growth and reduces the amount of oxygen needed. If alevins are prematurely pushed out of one tray, they will have the opportunity to settle out in a lower tray.
Efficient use of hatching floor space is greatly enhanced by the incubator described above because the ratio of eggs per unit of floor space can be very high due to the vertical stacking of the units.
Gaseous exchange occurs as the water flows in a thin sheet. This exchange renews dissolved oxygen and eliminates some of the dissolved ammonia metabolic wastes.
Various modifications may be made in the construction without departing from the invention as will be apparent to one skilled in the art. For example, if desired, the incubators can be individually placed on vertical racks or shelves and operated as though stacked. This allows individual units to be removed while lower units are receiving water from above. Flow is horizontal through the substrate but this can be changed to upwelling by placing the substrate on a perforated false bottom about one half inch above the bottom of the tray. The exact dimensions are not critical and if desired longer units can be employed. For convenience the egg trays can be made in short sections which are hooked together for ease of insertion and removal. If desired more than one egg tray can be employed in each section.
Any suitable material can be employed to make to various sections, such as plywood or plastic. The egg trays are conveniently made of aluminum channel frames covered by a plastic mesh held in place by polyethylene strips.
|
A fish egg incubator consisting of an upper removable egg tray having a sen bottom and a lower trough containing a rugose material substance is described. Water flows continuously over both the egg tray and rugose substrate. The eggs hatch out on the screen tray and the alevins fall through the mesh to the rugose substrate where they continue the development to the fry stage. At the proper development stage the fry migrate out of the rugose substrate and are carried out by the water stream and are collected.
| 8
|
[0001] Cancers are still among the leading causes of death despite interdisciplinary approaches and exhaustive utilization of classical therapy modalities.
[0002] Metastasis is one of the most critical factors responsible for the failure of a cancer therapy. Although illustration of protein expression, gene array analysis and determination of critical factors in tumor tissue have improved the prognostic classification of tumors, it is still difficult to predict the risk of metastasis by way of studying the resected primary tumor (Jacquemier J et al., Cancer Res. 65:767-779, 2005; Garber K, Science 303:1754-5, 2004; Hengstler J G et al., Cancer Res. 59, 3206-3214, 1999; Hengstler J G et al., Int. J. Cancer 84, 388-395, 1999; Hengstler J G et al., Int. J. Cancer, 95, 121-127, 2001).
[0003] A typical example is cancer of the endometrium, the most common malignancy of the female genital tract. After total resection of the tumor, survival usually depends on the occurrence of metastases. Sites of a recurrence of cancer of the endometrium are paraaortic lymph nodes, bones, lung, pelvis, liver and vagina (Steiner E et al., Int J Gynecol Cancer 13:197-203, 2003). It is currently difficult to predict whether or not a primary tumor of the endometrium has metastasized.
[0004] The factors which regulate establishment of the metastatic phenotype are largely undefined. Some histopathological parameters such as tumor stage and histological degree are known to be associated with tumor-free survival (Steiner E et al., Int J Gynecol Cancer 13:197-203, 2003). However, it has been impossible to predict the risk of metastasis by way of quantifying critical factors in tumor tissue.
[0005] It was the object of the present invention to provide targeted structures for a diagnosis, prognosis and therapy of cancers. More specifically, it was the object of the present invention to identify molecular markers which make possible differential diagnosis between metastasizing and non-metastasizing tumors, in particular endometrial tumors.
[0006] This object is achieved according to the invention by the subject matter of the claims.
[0007] According to the invention, genetic markers are identified whose expression correlates with a metastatic behavior of cancer, in particular cancer of the endometrium. Such genetic markers relate to nucleic acids selected from the group consisting of (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c). The invention furthermore relates to proteins and peptides encoded by said nucleic acids.
[0008] The present invention generally relates to the diagnosis, prognosis, monitoring, i.e. determination, of regression, progression, the course and/or the onset, and to the therapy of neoplastic disorders such as tumor diseases, in particular tumor diseases of the endometrium and metastases thereof.
[0009] In one aspect the invention relates to a method of diagnosing and/or monitoring a neoplastic disorder in a patient, comprising (i) detecting and/or determining the amount of a nucleic acid selected from the group consisting of: (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c), and/or (ii) detecting and/or determining the amount of a protein or peptide encoded by the nucleic acid of (i) or of a part or derivative thereof, and/or (iii) detecting and/or determining the amount of an antibody which is specific to the protein or peptide or part or derivative thereof of (ii), and/or (iv) detecting and/or determining the amount of a T lymphocyte which is specific to the protein or peptide or part or derivative thereof of (ii), where appropriate in a complex with an MHC molecule, in a biological sample isolated from a patient.
[0010] In particular embodiments, the patient has a neoplastic disorder, is suspected of suffering from or contracting a neoplastic disorder, or has a risk of a neoplastic disorder. In further embodiments, the patient has metastasis of a neoplastic disorder, is suspected of suffering from or contracting metastasis of a neoplastic disorder or has a risk of metastasis of a neoplastic disorder. In particular embodiments, the patient has undergone or is intended to undergo treatment of a neoplastic disorder, such as treatment by tumor resection, chemotherapy and/or radiotherapy.
[0011] Preferably, a presence of the nucleic acid, the protein or peptide or the part or derivative thereof, the antibody and/or the T lymphocyte and/or an increased amount of said nucleic acid, said protein or peptide or said part or derivative thereof, said antibody and/or said T lymphocyte in comparison with a patient without the neoplastic disorder, without a risk of said neoplastic disorder, without metastasis of said neoplastic disorder and/or without a risk of metastasis of said neoplastic disorder indicates the presence of said neoplastic disorder, a risk of said neoplastic disorder, metastasis of said neoplastic disorder and/or a risk of metastasis of said neoplastic disorder.
[0012] In a further aspect, the invention relates to a method of evaluating and/or predicting the metastatic behavior and/or the recurrence of a neoplastic disorder, comprising (i) detecting and/or determining the amount of a nucleic acid selected from the group consisting of: (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c), and/or (ii) detecting and/or determining the amount of a protein or peptide encoded by the nucleic acid of (i) or of a part or derivative thereof, and/or (iii) detecting and/or determining the amount of an antibody which is specific to the protein or peptide or part or derivative thereof of (ii), and/or (iv) detecting and/or determining the amount of a T lymphocyte which is specific to the protein or peptide or part or derivative thereof of (ii), in a biological sample isolated from a patient.
[0013] In particular embodiments, the patient has a neoplastic disorder, is suspected of suffering from or contracting a neoplastic disorder, or has a risk of a neoplastic disorder. In further embodiments, the patient has metastasis of a neoplastic disorder, is suspected of suffering from or contracting metastasis of a neoplastic disorder or has a risk of metastasis of a neoplastic disorder. In particular embodiments, the patient has undergone or is intended to undergo treatment of a neoplastic disorder, such as treatment by tumor resection, chemotherapy and/or radiotherapy.
[0014] Preferably, a presence of the nucleic acid, the protein or peptide or the part or derivative thereof, the antibody and/or the T lymphocyte and/or an increased amount of said nucleic acid, said protein or peptide or said part or derivative thereof, said antibody and/or said T lymphocyte in comparison with a patient without the neoplastic disorder, without a risk of said neoplastic disorder, without metastasis of said neoplastic disorder, without a risk of metastasis of said neoplastic disorder, without a recurrence of said neoplastic disorder and/or without a risk of a recurrence of said neoplastic disorder indicates the presence of metastasis or recurrence of said neoplastic disorder or a risk of metastasis or recurrence of said neoplastic disorder.
[0015] The methods of the invention preferably enable a prognosis to be made on whether metastasis of a neoplastic disorder has occurred or will occur. Preferably, the methods of the invention allow benign and malignant transformations to be distinguished and may provide information on the success of treatment of a neoplastic disorder which has been carried out or is to be carried out, such as treatment by way of tumor resection, chemotherapy and/or radiotherapy. More specifically, the methods of the invention may give information on the probability of a recurrence in a treatment of a neoplastic disorder which has been carried out or is to be carried out.
[0016] The skilled worker is familiar with possibilities of detecting and/or determining the amount in the methods of the invention.
[0017] In particular embodiments, detection and/or determination of the amount in the methods of the invention comprises (i) contacting the biological sample with an agent which binds specifically to the nucleic acid, to the protein or peptide or the part or derivative thereof, to the antibody or to the T lymphocyte, and (ii) detecting the formation of a complex between said agent and said nucleic acid, said protein or peptide or said part or derivative thereof, said antibody or said T lymphocyte.
[0018] A nucleic acid may be detected or the amount of a nucleic acid may be determined according to the invention by using an oligonucleotide or polynucleotide probe which hybridizes specifically with said nucleic acid, or by said nucleic acid being amplified selectively, preferably amplified by polymerase chain reaction. In one embodiment, the probe comprises a sequence of 6-50, in particular 10-30, 15-30 or 20-30, contiguous nucleotides from the nucleic acid to be detected.
[0019] A protein or peptide or a part or derivative thereof may be detected or the amount of a protein or peptide or of a part or derivative thereof may be determined according to the invention by using an antibody which binds specifically to said protein or peptide or to said part or derivative thereof.
[0020] In one embodiment, the protein or peptide to be detected or the part or derivative thereof is complexed with an MHC molecule.
[0021] An antibody may be detected or the amount of an antibody may be determined according to the invention by using a protein or peptide which binds specifically to said antibody.
[0022] A T lymphocyte may be detected or the amount thereof may be determined according to the invention by using a cell which presents a complex between a protein or peptide and an MHC molecule to which the T lymphocyte is specific, said cell being preferably an antigen-presenting cell. Where appropriate, a T lymphocyte is detected or the amount thereof is determined by way of detecting its proliferation, cytokine production and/or cytotoxic activity caused by specific stimulation by the complex between the protein or peptide and an MHC molecule. A T lymphocyte may also be detected or the amount thereof may be determined by means of recombinant MHC molecules or complexes of a plurality of MHC molecules loaded with a protein or peptide.
[0023] The agent used for detecting or determining the amount, in particular the oligonucleotide or polynucleotide probe, the antibody, the protein or peptide or the cell, are preferably detectably labeled. In particular embodiments, the detectable marker is a radioactive marker, fluorescent marker or enzyme marker.
[0024] In a further aspect, the invention relates to a pharmaceutical composition which comprises one or more components selected from the group consisting of (i) a nucleic acid selected from the group consisting of: (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c), (ii) a protein or peptide encoded by the nucleic acid of (i), a part thereof of at least 8 consecutive amino acids, and a derivative thereof, (iii) an antibody which binds to the protein or peptide or the part or derivative thereof of (ii), (iv) a host cell which expresses the protein or peptide or the part or derivative thereof of (ii), and (v) complexes between the protein or peptide or the part or derivative thereof of (ii) and an MHC molecule.
[0025] The one or more components present in the pharmaceutical composition, in particular the nucleic acid and the antibody, preferably recognize a genetic marker identified according to the invention or a protein or peptide encoded by said genetic marker. In a particular embodiment, the nucleic acid present in the pharmaceutical composition of the invention is an antisense nucleic acid which hybridizes with a nucleic acid of a genetic marker identified according to the invention. In another embodiment, the antibody present in a pharmaceutical composition of the invention recognizes a protein or peptide encoded by a genetic marker identified according to the invention and, in a particularly preferred embodiment of the invention, is coupled to a therapeutic or diagnostic agent and/or recruits natural or artificial effector mechanisms, in particular effector mechanisms of an immune reaction, to cells which express a protein or peptide encoded by a genetic marker identified according to the invention.
[0026] In another embodiment, administration of a pharmaceutical composition of the invention increases the amount of complexes between an MHC molecule and a protein or peptide encoded by a genetic marker identified according to the invention or a part or derivative thereof. Such an increase in the amount of complexes may be provided by directly administering the latter, where appropriate on the surface of antigen-presenting cells, or by administering a protein or peptide encoded by a genetic marker identified according to the invention or a part or derivative thereof or a nucleic acid coding therefor, where appropriate in a host cell. In particular embodiments, administration of a pharmaceutical composition may induce the death of tumor cells, reduce the growth of tumor cells and/or cause secretion of cytokines.
[0027] A nucleic acid may be present in the pharmaceutical composition in an expression vector and functionally linked to a promoter. An antisense nucleic acid present in a pharmaceutical composition of the invention preferably comprises a sequence of 6-50, in particular 10-30, 15-30 or 20-30, contiguous nucleotides.
[0028] A host cell present in a pharmaceutical composition of the invention may secrete the protein or peptide or the part or derivative thereof, express said protein or peptide or said part or derivative thereof on the surface or may additionally express an MHC molecule which binds to said protein or peptide or said part or derivative thereof. In one embodiment, the host cell expresses the MHC molecule endogenously. In another embodiment, the host cell expresses the MHC molecule and/or the protein or peptide or the part or derivative thereof in a recombinant manner. The host cell is preferably nonproliferative. In a preferred embodiment, the host cell is an antigen-presenting cell.
[0029] An antibody present in a pharmaceutical composition of the invention may be a monoclonal antibody. In other embodiments, the antibody is a chimeric or humanized antibody, a fragment of a natural antibody, or a synthetic antibody. The antibody may be coupled to a therapeutic or diagnostic agent.
[0030] A pharmaceutical composition of the invention may comprise a pharmaceutically suitable carrier and/or an adjuvant.
[0031] A pharmaceutical composition of the invention is preferably used for treating or diagnosing a neoplastic disorder such as a tumor disease, preferably a tumor disease of the endometrium or metastases thereof. In preferred embodiments the tumor is a metastasizing tumor.
[0032] The present invention furthermore relates to a nucleic acid selected from the group consisting of (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c). The invention furthermore relates to a nucleic acid which codes for a protein or peptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 8, a part thereof of at least 8 consecutive amino acids and a derivative thereof.
[0033] In a further aspect, the invention relates to a recombinant nucleic acid molecule, in particular DNA or RNA molecule, which comprises a nucleic acid of the invention.
[0034] The invention also relates to host cells which contain a nucleic acid of the invention or a recombinant nucleic acid molecule of the invention.
[0035] The host cell may further comprise a nucleic acid coding for an MHC molecule. In one embodiment, the host cell expresses the MHC molecule endogenously. In another embodiment, the host cell expresses the MHC molecule and/or the nucleic acid of the invention in a recombinant manner. The host cell is preferably nonproliferative. In a preferred embodiment, the host cell is an antigen-presenting cell.
[0036] In a further aspect, the invention relates to a protein or peptide encoded by a nucleic acid selected from the group consisting of (a) a nucleic acid which comprises a nucleic acid sequence selected from the group consisting of SEQ ID NO: 1-7, a part of at least 30 consecutive nucleotides thereof and a derivative thereof, (b) a nucleic acid which hybridizes with the nucleic acid of (a) under stringent conditions, (c) a nucleic acid which is degenerated with respect to the nucleic acid of (a) or (b), and (d) a nucleic acid which is complementary to the nucleic acid of (a), (b) or (c). In a preferred embodiment, the invention relates to a protein or peptide comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 8, a part thereof of at least 8 consecutive amino acids and a derivative thereof.
[0037] In a further aspect, the invention relates to an antibody which binds to a protein or peptide of the invention. In further embodiments, the antibody is a chimeric or humanized antibody or a fragment of an antibody. An antibody of the invention may be a polyclonal or monoclonal antibody.
[0038] The term “to bind” relates according to the invention to specific binding. “Specific binding” means that binding to a target such an epitope, to which a binding agent such as an antibody is specific, is stronger than binding to a different target. “Stronger binding” may be characterized, for example, by a lower dissociation constant.
[0039] The invention furthermore relates to a conjugate between an antibody of the invention and a therapeutic or diagnostic agent. In one embodiment, the therapeutic or diagnostic agent is a toxin.
DETAILED DESCRIPTION OF THE INVENTION
[0040] According to the invention, a nucleic acid is preferably deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). According to the invention, nucleic acids comprise genomic DNA, cDNA, mRNA, recombinantly produced and chemically synthesized molecules. A nucleic acid may be present according to the invention as a single-stranded or double-stranded and linear or covalently closed circular molecule.
[0041] According to the invention, the term “nucleic acid” also comprises derivatives of nucleic acids. “Derivative” of a nucleic acid means according to the invention that single or multiple, preferably at least 2, at least 4, at least 6, and preferably up to 3, up to 4, up to 5, up to 6, up to 10, up to 15 or up to 20, substitutions, deletions and/or additions of nucleotides are present in the nucleic acid. The term “derivative” of a nucleic acid furthermore also comprises chemical derivatization of a nucleic acid at a nucleotide base, at the sugar or at the phosphate, and nucleic acids containing not naturally occurring nucleotides and nucleotide analogs.
[0042] The nucleic acids described according to the invention are preferably isolated. The term “isolated nucleic acid” means according to the invention that the nucleic acid has been (i) amplified in vitro, for example by polymerase chain reaction (PCR), (ii) recombinantly produced by cloning, (iii) purified, for example by cleavage and gel-electrophoretic fractionation, or (iv) synthesized, for example by chemical synthesis. An isolated nucleic acid is a nucleic acid available to manipulation by recombinant DNA techniques.
[0043] A nucleic acid is “complementary” to another nucleic acid if the two sequences can hybridize with one another and form a stable duplex, said hybridization being carried out preferably under conditions which allow specific hybridization between polynucleotides (stringent conditions). Stringent conditions are described, for example, in Molecular Cloning: A Laboratory Manual, J. Sambrook et al., ed., 2nd edition, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. 1989 or Current Protocols in Molecular Biology, F. M. Ausubel et al., ed., John Wiley & Sons, Inc., New York, and refer, for example, to the hybridization at 65° C. in hybridization buffer (3.5×SSC, 0.02% Ficoll, 0.02% polyvinylpyrrolidone, 0.02% bovine serum albumin, 2.5 mM NaH 2 PO 4 (pH 7), 0.5% SDS, 2 mM EDTA). SSC is 0.15 M sodium chloride/0.15 M sodium citrate, pH 7. After hybridization, the membrane to which the DNA has been transferred, is washed, for example, in 2×SSC at room temperature and then in 0.1-0.5×SSC/0.1×SDS at temperatures up to 68° C.
[0044] According to the invention, complementary nucleic acids have at least 40%, in particular at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, and preferably at least 95%, at least 98% or at least 99%, identical nucleotides.
[0045] The term “% identity” is intended to refer to a percentage of nucleotides which are identical in an optimal alignment between two sequences to be compared, with said percentage being purely statistical, and the differences between the two sequences may be randomly distributed over the entire length of the sequence and the sequence to be compared may comprise additions or deletions in comparison with the reference sequence, in order to obtain optimal alignment between two sequences. Comparisons of two sequences are usually carried out by comparing said sequences, after optimal alignment, with respect to a segment or “window of comparison”, in order to identify local regions of corresponding sequences. The optimal alignment for a comparison may be carried out manually or with the aid of the local homology algorithm by Smith and Waterman, 1981, Ads App. Math. 2, 482, with the aid of the local homology algorithm by Neddleman and Wunsch, 1970, J. Mol. Biol. 48, 443, and with the aid of the similarity search algorithm by Pearson and Lipman, 1988, Proc. Natl. Acad. Sci. USA 85, 2444 or with the aid of computer programs using said algorithms (GAP, BESTFIT, FASTA, BLAST P, BLAST N and TFASTA in Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Drive, Madison, Wis.).
[0046] Percentage identity is obtained by determining the number of identical positions in which the sequences to be compared correspond, dividing this number by the number of positions compared and multiplying this result by 100.
[0047] For example, the BLAST program “BLAST 2 sequences” which is available on the website http://www.ncbi.nlm.nih.gov/blast/bl2seq/wblast2.cgi may be used.
[0048] According to the invention, nucleic acids may be present alone or in combination with other nucleic acids which may be homologous or heterologous. In particular embodiments, a nucleic acid according to the invention is functionally linked to expression control sequences which may be homologous or heterologous with respect to said nucleic acid, with the term “homologous” here referring to the fact that a nucleic acid is also functionally linked naturally to the expression control sequence, and the term “heterologous” referring to the fact that a nucleic acid is not naturally functionally linked to the expression control sequence.
[0049] A nucleic acid, preferably a transcribable nucleic acid and in particular a nucleic acid coding for a peptide or protein, and an expression control sequence are “functionally” linked to one another, if they are covalently linked to one another in such a way that transcription or expression of the nucleic acid is under the control or under the influence of the expression control sequence. If the nucleic acid is to be translated into a functional peptide or protein, induction of an expression control sequence when it is functionally linked to the coding sequence results in transcription of said coding sequence, without causing a frame shift in the coding sequence or the coding sequence being unable to be translated into the desired peptide or protein.
[0050] The term “expression control sequence” comprises according to the invention promoters, ribosome-binding sequences and other control elements which control transcription of a gene or translation of the derived RNA. In particular embodiments of the invention, the expression control sequences can be regulated. The precise structure of expression control sequences may vary depending on the species or cell type but usually includes 5′-untranscribed and 5′- and 3′-untranslated sequences involved in initiating transcription and translation, respectively, such as TATA box, capping sequence, CAAT sequence and the like. More specifically, 5′-untranscribed expression control sequences include a promoter region which encompasses a promoter sequence for transcription control of the functionally linked nucleic acid. Expression control sequences may also include enhancer sequences or upstream activator sequences.
[0051] The term “promoter” or “promoter region” refers to a DNA sequence upstream (5′) of the coding sequence of a gene and controls expression of said coding sequence by providing a recognition and binding site for RNA polymerase. The promoter region may include further recognition or binding sites for further factors involved in regulating transcription of said gene. A promoter may control transcription of a prokaryotic or eukaryotic gene. A promoter may be “inducible” and initiate transcription in response to an inducer, or may be “constitutive” if transcription is not controlled by an inducer. An inducible promoter is expressed only to a very small extent or not at all, if an inducer is absent. In the presence of the inducer, the gene is “switched on” or the level of transcription is increased. This is usually mediated by binding of a specific transcription factor.
[0052] Examples of promoters preferred according to the invention are promoters for SP6, T3 or T7 polymerase.
[0053] According to the invention, the term “expression” is used in its most general meaning and comprises production of RNA or of RNA and protein. It also comprises partial expression of nucleic acids. Furthermore, expression may be transient or stable. With respect to RNA, the term “expression” or “translation” refers in particular to production of peptides or proteins.
[0054] Furthermore, a nucleic acid coding for a protein or peptide may according to the invention be linked to another nucleic acid coding for a peptide sequence which controls secretion of the protein or peptide encoded by said nucleic acid from a host cell. According to the invention, a nucleic acid may also be linked to another nucleic acid coding for a peptide sequence which causes anchoring of the encoded protein or peptide to the cell membrane of a host cell or compartmentalization thereof into particular organelles of said cell. Similarly, a linkage to a nucleic acid representing a reporter gene or any “tag” may be established.
[0055] In a preferred embodiment, a nucleic acid is present according to the invention in a vector, where appropriate with a promoter controlling expression of said nucleic acid. The term “vector” is used here in its most general meaning and comprises any intermediate vehicles for a nucleic acid which, for example, enable said nucleic acid to be introduced into prokaryotic and/or eukaryotic cells and, where appropriate, to be integrated into a genome. Such vectors are preferably replicated and/or expressed in the cell. Vectors comprise plasmids, phagemids or viral genomes. The term “plasmid”, as used herein, generally relates to a construct of extrachromosomal genetic material, usually a circular DNA duplex, which can replicate independently of chromosomal DNA.
[0056] According to the invention, the term “host cell” refers to any cell which can be transformed or transfected with an exogenous nucleic acid, preferably DNA or RNA. The term “host cell” comprises according to the invention prokaryotic (e.g. E. coli ) or eukaryotic cells (e.g. mammalian cells, in particular cells from humans, yeast cells and insect cells). Particular preference is given to mammalian cells such as cells from humans, mice, hamsters, pigs, goats and primates. The cells may be derived from a multiplicity of tissue types and comprise primary cells and cell lines. Specific examples include keratinocytes, peripheral blood leukocytes, bone marrow stem cells and embryonic stem cells. In other embodiments, the host cell is an antigen-presenting cell, the term “antigen-presenting cell” comprising according to the invention dendritic cells, monocytes and macrophages. A nucleic acid may be present in the host cell in a single or in several copies and, in one embodiment, is expressed in the host cell.
[0057] In those cases of the invention, in which an MHC molecule presents a protein or peptide, an expression vector may also comprise a nucleic acid sequence coding for said MHC molecule. The nucleic acid sequence coding for the MHC molecule may be present on the same expression vector as the nucleic acid coding for the protein or peptide, or both nucleic acids may be present on different expression vectors. In the latter case, the two expression vectors may be cotransfected into one cell. If a host cell expresses neither the protein or peptide nor the MHC molecule, both nucleic acids coding therefor may be transfected into the cell either on the same expression vector or on different expression vectors. If the cell already expresses the MHC molecule, only the nucleic acid sequence coding for the protein or peptide may be transfected into the cell.
[0058] The invention also comprises kits for amplifying a nucleic acid in order to detect thereby said nucleic acid or determine its amount. Such kits comprise, for example, a pair of amplification primers which hybridize to the nucleic acid to be amplified. The primers preferably comprise a sequence of from 6-50, in particular 10-30, 15-30 or 20-30, contiguous nucleotides of the nucleic acid to be amplified and do not overlap in order to avoid formation of primer dimers. One of said primers will hybridize to a strand of the nucleic acid to be amplified and the other primer will hybridize to the complementary strand in an arrangement which allows amplification of the nucleic acid.
[0059] “Antisense nucleic acids” may be used for regulating, in particular reducing, expression of a nucleic acid.
[0060] The term “antisense nucleic acid” means according to the invention an oligonucleotide which is an oligoribonucleotide, oligodeoxyribonucleotide, modified oligoribonucleotide or modified oligodeoxyribonucleotide and which hybridizes under physiological conditions to DNA comprising a particular gene or to mRNA of said gene, thereby inhibiting transcription of said gene and/or translation of said mRNA. An “antisense nucleic acid” comprises according to the invention also a construct which contains a nucleic acid or part thereof in reverse orientation with respect to its natural promoter. An antisense transcript of a nucleic acid or of a part thereof may form a duplex with the naturally occurring mRNA which specifies a peptide or protein, thus preventing translation of said mRNA into said peptide or protein. Another option is the use of ribozymes for inactivating a nucleic acid. Preferred antisense oligonucleotides of the invention have a sequence of 6-50, in particular 10-30, 15-30 or 20-30, contiguous nucleotides of the target nucleic acid and are preferably fully complementary to said target nucleic acid or a part thereof.
[0061] In preferred embodiments, the antisense oligonucleotide hybridizes with an N-terminal or 5′ upstream site such as a translation initiation site, transcription initiation site or promoter site. In other embodiments, the antisense oligonucleotide hybridizes to a 3′-untranslated region or mRNA splicing site.
[0062] In one embodiment, an oligonucleotide according to the invention consists of ribonucleotides, deoxyribonucleotides or a combination thereof. The 5′ end of a nucleotide and the 3′ end of another nucleotide are linked here via phosphodiester bond. These oligonucleotides may be synthesized in the usual manner or produced recombinantly.
[0063] In preferred embodiments, an oligonucleotide of the invention is a “modified” oligonucleotide. Said oligonucleotide may be modified in very different ways, for example in order to increase its stability or therapeutic efficacy, without impeding its ability to bind to its target. The term “modified oligonucleotide” means according to the invention an oligonucleotide in which (i) at least two of its nucleotides are linked to one another by a synthetic internucleoside bond (i.e. an internucleoside bond that is not a phosphodiester bond), and/or (ii) a chemical group which is normally not present in nucleic acids is covalently linked to the oligonucleotide. Preferred synthetic internucleoside bonds are phosphorothioates, alkyl phosphonates, phosphorodithioates, phosphate esters, alkyl phosphonothioates, phosphoramidates, carbamates, carbonates, phosphate triesters, acetamidates, carboxymethyl esters and peptides.
[0064] The term “modified oligonucleotide” also comprises oligonucleotides having one or more covalently modified bases and/or one or more covalently modified sugars. Examples of “modified oligonucleotides” include oligonucleotides containing sugar residues which are covalently bound to low molecular weight organic groups other than a hydroxyl group in the 3′ position and a phosphate group in the 5′ position. Modified oligonucleotides may comprise, for example, a 2′-O-alkylated ribose residue or a sugar other than ribose, such as arabinose.
[0065] The term “peptide” relates to substances which comprise at least two, at least 3, at least 4, at least 6, at least 8, at least 10, at least 13, at least 16, at least 20 and preferably up to 50, 100 or 150, consecutive amino acids which are linked to one another via peptide bonds. The term “protein” relates to large peptides, preferably peptides with at least 151 amino acids, but the terms “peptide” and “protein” are used herein generally as synonyms.
[0066] The proteins and peptides described according to the invention are preferably isolated. The terms “isolated protein” or “isolated peptide” mean that the protein or peptide is separated from its natural environment. An isolated protein or peptide may be in an essentially purified state. The term “essentially purified” means that the protein or peptide is essentially free of other substances with which it is associated in nature or in vivo.
[0067] Such proteins and peptides are used, for example, in production of antibodies and can be employed in an immunological or diagnostic assay or as therapeutics. Proteins and peptides described according to the invention may be isolated from biological samples such as tissue homogenates or cell homogenates and may also be expressed recombinantly in a multiplicity of prokaryotic or eukaryotic expression systems.
[0068] “Derivatives” of a protein or peptide or of an amino acid sequence in accordance with the present invention include amino acid insertion variants, amino acid deletion variants and/or amino acid substitution variants.
[0069] Amino acid insertion variants include amino- and/or carboxy-terminal fusions, and insertions of single or multiple amino acids in a particular amino acid sequence. In amino acid sequence variants with an insertion, one or more amino acid residues are introduced into a predetermined site in an amino acid sequence, although random insertion with suitable screening of the resulting product is also possible. Amino acid deletion variants are characterized by the removal of one or more amino acids from the sequence. Amino acid substitution variants are distinguished by at least one residue in the sequence being removed and another residue being inserted in its place. The modifications are preferably present at positions in the amino acid sequence which are not conserved between homologous proteins or peptides and/or amino acids are preferably replaced by others having similar properties such as hydrophobicity, hydrophilicity, electronegativity, volume of the side chain and the like (conservative substitution). Conservative substitutions relate for example to replacement of one amino acid with another amino acid which is listed below in the same group as the substituted amino acid:
[0000] 1. Small aliphatic, nonpolar or slightly polar residues: Ala, Ser, Thr (Pro, Gly)
2. Negatively charged residues and their amides: Asn, Asp, Glu, Gln
3. Positively charged residues: His, Arg, Lys
4. Large aliphatic, nonpolar residues: Met, Leu, Ile, Val (Cys)
5. Large aromatic residues: Phe, Tyr, Trp.
[0070] Three residues are put in parentheses due to their particular role in protein architecture. Gly is the only residue without a side chain and thus confers flexibility on said chain. Pro has an unusual geometry which greatly restricts the chain. Cys can form a disulfide bridge.
[0071] The amino acid variants described above can easily be prepared with the aid of known peptide synthesis techniques such as, for example, by “Solid phase synthesis” (Merrifield, 1964) and similar methods or by recombinant DNA manipulation. The manipulation of DNA sequences for preparing proteins and peptides with substitutions, insertions or deletions is described in detail in Sambrook et al. (1989), for example.
[0072] According to the invention, “derivatives” of proteins or peptides also include single or multiple substitutions, deletions and/or additions of any molecules which are associated with the protein or peptide, such as carbohydrates, lipids and/or proteins or peptides. The term “derivative” furthermore also extends to all functional chemical equivalents of said proteins and peptides and to substances containing not only amino acid components but also non-amino acid components such as sugars and phosphate structures, and also include substances containing bonds such as ester bonds, thioether bonds or disulfide bonds.
[0073] A part or fragment of a protein or peptide has according to the invention preferably a functional property of the protein or peptide from which it is derived. Such functional properties include, for example, the interaction with antibodies or the interaction with other peptides or proteins. An important property is the ability to form a complex with MHC molecules and, where appropriate, to generate an immune reaction, for example by stimulating cytotoxic or helper T cells. A part or fragment of a protein comprises according to the invention preferably a sequence of at least 6, at least 8, at least 10, at least 12, at least 15, at least 20, or at least 30, and preferably up to 8, 10, 12, 15, 20, 30 or 50, consecutive amino acids of said protein or peptide.
[0074] A part or a fragment of a nucleic acid coding for a protein or peptide relates according to the invention preferably to that part of the nucleic acid which codes at least for the protein or peptide and/or for a part or a fragment of said protein or peptide, as defined above.
[0075] Antisera containing antibodies which bind specifically to a target may be produced by various standard methods; cf., for example, “Monoclonal Antibodies: A Practical Approach” by Philip Shepherd, Christopher Dean ISBN 0-19-963722-9, “Antibodies: A Laboratory Manual” by Ed Harlow, David Lane ISBN: 0879693142 and “Using Antibodies: A Laboratory Manual: Portable Protocol NO” by Edward Harlow, David Lane, Ed Harlow ISBN: 0879695447. It is also possible here to generate antibodies having affinity and specificity which recognize complex membrane proteins in their native form (Azorsa et al., J. Immunol. Methods 229: 35-48, 1999; Anderson et al., J. Immunol. 143: 1899-1904, 1989; Gardsvoll, J. Immunol. Methods 234: 107-116, 2000). This is especially important to the production of antibodies which are intended to be used therapeutically, but also to many diagnostic applications. This may involve immunization with the complete protein, with extracellular subsequences, as well as with cells which express the target molecule in a physiologically folded form.
[0076] Monoclonal antibodies are traditionally produced with the aid of the hybridoma technology (technical details: see “Monoclonal Antibodies: A Practical Approach” by Philip Shepherd, Christopher Dean ISBN 0-19-963722-9; “Antibodies: A Laboratory Manual” by Ed Harlow, David Lane ISBN: 0879693142, “Using Antibodies: A Laboratory Manual: Portable Protocol NO” by Edward Harlow, David Lane, Ed Harlow ISBN: 0879695447).
[0077] It is known that only a small part of an antibody molecule, the paratope, is involved in binding of the antibody to its epitope (cf. Clark, W. R. (1986), The Experimental Foundations of Modern Immunology , Wiley & Sons, Inc., New York; Roitt, I. (1991), Essential Immunology, 7th edition, Blackwell Scientific Publications, Oxford). The pFc′ and Fc regions, for example, are effectors of the complement cascade but they are not involved in antigen binding. An antibody from which the pFc′ region has been enzymatically removed or which has been produced without the pFc′ region, referred to as F(ab′) 2 fragment, carries both antigen binding sites of a complete antibody. Similarly, an antibody from which the Fc region has been enzymatically removed or which has been produced without the Fc region, referred to as Fab fragment, carries one antigen binding site of an intact antibody molecule. Furthermore, Fab fragments consist of a covalently bound light chain of an antibody and part of the heavy chain of said antibody, referred to as Fd. The Fd fragments are the major determinants of antibody specificity (a single Fd fragment may be associated with up to ten different light chains, without altering specificity of the antibody), and Fd fragments when isolated retain the ability to bind to an epitope.
[0078] Within the antigen-binding part of an antibody, there are complementarity-determining regions (CDRs) which directly interact with the epitope of the antigen, and framework regions (FRs) which maintain the tertiary structure of the paratope. Both the Fd fragment of the heavy chain and the light chain of IgG immunoglobulins contain four framework regions (FR1 to FR4) which are separated in each case by three complementarity-determining regions (CDR1 to CDR3). The CDRs and in particular CDR3 regions and even more the CDR3 region of the heavy chain are largely responsible for antibody specificity.
[0079] It is known that non-CDR regions of a mammalian antibody can be replaced with similar regions of antibodies having the same or a different specificity, with the specificity to the epitope of the original antibody being retained. This made it possible to develop “humanized” antibodies in which nonhuman CDRs are covalently linked to human FR and/or Fc/pFc′ regions to produce a functional antibody.
[0080] A different example is described in WO 92/04381 by way of producing and using humanized murine RSV antibodies in which at least part of the murine FR regions have been replaced with FR regions of human origin. Such antibodies, including fragments of intact antibodies with antigen binding capability, are frequently referred to as “chimeric” antibodies.
[0081] According to the invention, the term “antibody” also includes F(ab′) 2 , Fab, Fv and Fd antibody fragments, chimeric antibodies in which the Fc and/or FR and/or CDR1 and/or CDR2 and/or light chain CDR3 regions have been replaced with homologous human or nonhuman sequences, chimeric F(ab′) 2 fragment antibodies in which the FR and/or CDR1 and/or CDR2 and/or light chain CDR3 regions have been replaced with homologous human or nonhuman sequences, chimeric Fab fragment antibodies in which the FR and/or CDR1 and/or CDR2 and/or light chain CDR3 regions have been replaced with homologous human or nonhuman sequences and chimeric Fd fragment antibodies in which the FR and/or CDR1 and/or CDR2 regions have been replaced with homologous human or nonhuman sequences. According to the invention, the term “antibody” also comprises single-chain antibodies.
[0082] Antibodies may also be coupled to specific diagnostic agents in order to display, for example, cells and tissues which express particular proteins or peptides. They may also be coupled to therapeutic agents.
[0083] Diagnostic agents include any labeling which is suitable for: (i) providing a detectable signal, (ii) interacting with a second label in order to modify the detectable signal provided by the first or second label, for example FRET (fluorescence resonance energy transfer), (iii) influencing mobility such as electrophoretic mobility by means of charge, hydrophobicity, form or other physical parameters, or (iv) providing a capture group, for example affinity complexing, antibody/antigen complexing or ionic complexing. Suitable labels are structures such as fluorescent labels, luminescent labels, chromophore labels, radioisotopic labels, isotopic labels, preferably stable isotopic labels, enzyme labels, particle labels, in particular metal particle labels, magnetic particle labels, polymeric particle labels, small organic molecules such as biotin, ligands of receptors or binding molecules such as cell adhesion proteins or lectins, and labeling sequences comprising nucleic acid and/or amino acid sequences. Diagnostic agents include, but are not limited to, barium sulfate, iocetamic acid, iopanoic acid, calcium ipodate, sodium diatrizoate, meglumine diatrizoate, metrizamide, sodium tyropanoate and radio diagnostic agents, including positron emitters such as fluorine-18 and carbon-11, gamma emitters such as iodine-123, technetium-99m, iodine-131 and indium-111, and nuclides for nuclear magnetic resonance, such as fluorine and gadolinium.
[0084] The term “therapeutic agent” means according to the invention any substance capable of exerting a therapeutic action, and includes, but is not limited to, anticancer agents, compounds provided with radioactive iodine, toxins, cytostatic or cytolytic drugs, etc. Anticancer agents include, for example, aminoglutethimide, azathioprine, bleomycin sulfate, busulfan, carmustine, chlorambucil, cisplatin, cyclophosphamide, cyclosporin, cytarabidine, dacarbazine, dactinomycin, daunorubin, doxorubicin, taxol, etoposide, fluoruracil, interferon-α, lomustine, mercaptopurine, methotrexate, mitotane, procarbazine HCl, thioguanine, vinblastine sulfate and vincristine sulfate. Further anticancer agents are described, for example, in Goodman and Gilman, “The Pharmacological Basis of Therapeutics”, 8th edition, 1990, McGraw-Hill, Inc., especially chapter 52 (Antineoplastic Agents (Paul Calabresi and Bruce A. Chabner)). Toxins may be proteins such as pokeweed antiviral protein, cholera toxin, pertussis toxin, ricin, gelonin, abrin, diphtheria exotoxin, or Pseudomonas exotoxin. Toxin residues may also be high energy-emitting radionuclides such as cobalt-60.
[0085] The term “major histocompatibility complex” or “MHC” relates to a complex of genes that is present in all vertebrates. MHC proteins or molecules are involved in the signaling between lymphocytes and antigen-presenting cells in normal immune reactions, wherein they bind peptides and present them for recognition by T cell receptors. MHC molecules bind peptides within an intracellular processing compartment and present said peptides on the surface of antigen-presenting cells for recognition by T cells. The human MHC region, also referred to as HLA, is located on chromosome 6 and comprises the class I and class II regions. In a preferred embodiment according to all aspects of the invention, an MHC molecule is an HLA molecule.
[0086] The term “patient” includes according to the invention male and female patients, preferably female patients. Examples of patients include according to the invention humans, nonhuman primates or other animals, in particular mammals such as cows, horses, pigs, sheep, goats, dogs, cats or rodents such as mice and rats. In a particularly preferred embodiment, the patient is a human being.
[0087] According to the invention, the term “neoplastic disorder” relates to de novo formation of body tissues in the sense of disregulated, uncontrolled and/or autonomous excess growth, with the term “disorder” relating to any pathological state. Preference is given to a neoplastic disorder being according to the invention a tumor disease or cancer such as leukemias, seminomas, melanomas, teratomas, glyomas, cancers of the kidney, adrenal gland, thyroid, intestine, liver, colon, stomach, gastrointestinal tract, lymph nodes, esophagus, colorectum, pancreas, ear, nose and throat (ENT), breast, prostata, uterus, ovaries, bones, vagina and lung, and in particular cancer of the endometrium and metastases thereof which in the case of cancer of the endometrium, occur, in particular, in paraaortic lymph nodes, bones, lung, pelvis, liver and vagina. In a preferred embodiment, a neoplastic disorder is induced according to the invention by carcinogenesis. According to the invention, neoplasias relate to benign changes without metastasis and malignant changes, in particular with invasive growth and the formation of metastases.
[0088] According to the invention, the term “myometrium” relates to the strong middle layer of the uterine wall, formed by smooth muscles.
[0089] The term “recurrence” relates according to the invention to a relapse of a disease, in particular its recurrence after healing or apparent healing. With respect to a tumor disease, the term “recurrence” relates to the recurrence of tumors after initially successful treatment such as treatment by surgery, chemotherapy and/or radiotherapy.
[0090] The term “increased amount” preferably relates to an increase by at least 10%, in particular at least 20%, at least 50% or at least 100%. The amount of a substance is increased in a test specimen such as a biological sample with respect to a reference, even if said substance is detectable in the test specimen but is not present and/or not detectable in the reference.
[0091] According to the invention, a biological sample may be a tissue sample, including bodily fluids, and/or a cellular sample, and may be obtained in the usual manner such as by tissue biopsy, including punch biopsy, and by taking blood, bronchial aspirate, sputum, urine, feces or other bodily fluids.
[0092] The terms “T cell” and “T lymphocyte” include T helper cells and cytolytic or cytotoxic T cells.
[0093] Some therapeutic methods rely on a response of the immune system of a patient, which results in the lysis of antigen-presenting cells such as cancer cells presenting one or more peptides. This involves, for example, administering autologous cytotoxic T lymphocytes which are specific to a complex of a peptide and an MHC molecule to a patient having a cellular anomaly. In vitro production of such cytotoxic T lymphocytes has been disclosed.
[0094] In this connection, the invention relates to a therapeutic method which is referred to as adoptive transfer (Greenberg, J. Immunol. 136(5):1917, 1986; Riddel et al., Science 257:238, 1992; Lynch et al., Eur. J. Immunol. 21:1403-1410, 1991; Kast et al., Cell 59:603-614, 1989). This involves combining cells which present the desired complex (e.g. dendritic cells) with cytotoxic T lymphocytes of the patient to be treated, resulting in propagation of specific cytotoxic T lymphocytes. The propagated cytotoxic T lymphocytes are then administered to a patient having a cellular anomaly, with the anomalous cells presenting the specific complex. The cytotoxic T lymphocytes then lyse the anomalous cells, thereby achieving a desired therapeutic action.
[0095] Adoptive transfer is not the only form of therapy which can be applied according to the invention. Cytotoxic T lymphocytes may also be generated in vivo in a manner known per se. One method comprises using nonproliferative cells expressing the complex, such as irradiated tumor cells or cells which have been transfected with one or both genes necessary for presentation of the complex (i.e. the antigenic peptide and the presenting MHC molecule). A preferred form is that of introducing a protein or peptide which is characteristic for a tumor, in the form of recombinant RNA, into cells which then present the complex of interest. Such cells are recognized by autologous cytotoxic T lymphocytes which then propagate.
[0096] A similar action can be achieved by combining a protein or peptide with an adjuvant in order to make possible in vivo incorporation into antigen-presenting cells. The protein or peptide may be represented as such, as DNA (e.g. within a vector) or as RNA. The protein or peptide may be processed so as to produce a peptide partner for the HLA molecule. A presentation is also possible without further processing being required. This is the case in particular if peptides can bind to HLA molecules. Preference is given to administrative forms in which the total antigen is processed in vivo by a dendritic cell, since this may also produce helper T cell responses which are required for an effective immune response (Ossendorp et al., Immunol Lett. 74:75-79, 2000; Ossendorp et al., J. Exp. Med. 187:693-702, 1998).
[0097] The pharmaceutical compositions described according to the invention may also be employed as vaccines for immunization. The terms “immunization” or “vaccination” relate according to the invention to an increase or an activation of an immune reaction against an antigen. Animal models may be employed for testing an immunizing effect against cancer. It is possible, for example, for human cancer cells to be introduced into a mouse to create a tumor, and for one or more nucleic acids which code for proteins or peptides characteristic for cancer cells to be administered. The effect on the cancer cells (for example reduction in tumor size) can be measured as criterion for the efficacy of an immunization by the nucleic acid.
[0098] As part of the composition for immunization, preference is given to administering one or more antigens or stimulating fragments thereof together with one or more adjuvants to induce an immune response or increase an immune response. An adjuvant is a substance which is incorporated into the antigen or is administered together therewith and enhances the immune response. Adjuvants are able to enhance the immune response by providing an antigen reservoir (extracellularly or in macrophages), activating macrophages and/or stimulating certain lymphocytes. Adjuvants are known and include in a nonlimiting manner monophosphoryl-lipid-A (MPL, SmithKline Beecham), saponins such as QS21 (SmithKline Beecham), DQS21 (SmithKline Beecham; WO 96/33739), QS7, QS17, QS18 and QS-L1 (So et al., Mol. Cells. 7:178-186, 1997), incomplete Freund's adjuvant, complete Freund's adjuvant, vitamin E, montanide, alum, CpG oligonucleotides (cf. Kreig et al., Nature 374:546-9, 1995) and various water-in-oil emulsions which are prepared from biodegradable oils such as squalene and/or tocopherol. Preference is given to administering peptides in a mixture with DQS21/MPL. The ratio of DQS21 to MPL is typically about 1:10 to 10:1, preferably about 1:5 to 5:1 and in particular about 1:1. In a vaccine formulation for administration to humans, DQS21 and MPL are typically present in a range from about 1 μg to about 100 μg.
[0099] Other substances which stimulate an immune response in the patient may also be administered. For example, cytokines can be used for a vaccination because of their regulatory properties on lymphocytes. Such cytokines include, for example, interleukin-12 (IL-12) which has been shown to enhance the protective effects of vaccines (cf. Science 268:1432-1434, 1995), GM-CSF and IL-18.
[0100] The invention also provides for administration of nucleic acids, proteins or peptides. Proteins and peptides may be administered in a manner known per se. In one embodiment, nucleic acids are administered by ex vivo methods, i.e. by removing cells from a patient, genetically modifying said cells in order to introduce a nucleic acid, and reintroducing the modified cells into the patient. This usually comprises introducing in vitro a functional copy of a gene into the cells of a patient and returning the genetically modified cells to the patient. The functional copy of the gene is under the functional control of regulatory elements which allow the gene to be expressed in the genetically modified cells. Transfection and transduction methods are known to the skilled worker. The invention also provides for administration of nucleic acids in vivo by using vectors such as viruses and targeted liposomes.
[0101] In a preferred embodiment, a viral vector for administering a nucleic acid is selected from the group consisting of adenoviruses, adeno-associated viruses, poxviruses, including vaccinia virus and attenuated poxviruses, Semliki forest virus, retroviruses, Sindbis virus and Ty virus-like particles. Particular preference is given to adenoviruses and retroviruses. The retroviruses are normally replication-deficient (i.e. they are unable to produce infectious particles).
[0102] Various methods may be employed in order to introduce nucleic acids into cells in vitro or in vivo according to the invention. Such methods include transfection of nucleic acid-calcium phosphate precipitates, transfection of nucleic acids associated with DEAE, transfection or infection with the above viruses carrying the nucleic acids of interest, liposome-mediated transfection and the like. In particular embodiments, guiding of the nucleic acid to particular cells is preferred. In such embodiments, a carrier employed for administering a nucleic acid to a cell (e.g. a retrovirus or a liposome) may have a bound targeting molecule. For example, a molecule such as an antibody which is specific to a surface membrane protein on the target cell, or a ligand for a receptor on the target cell, may be incorporated into the nucleic acid carrier or bound thereto. If administration of a nucleic acid by liposomes is desired, it is possible to incorporate proteins which bind to a surface membrane protein which is associated with endocytosis into the liposome formulation in order to make targeting and/or uptake possible. Such proteins include capsid proteins or fragments thereof, which are specific to a particular cell type, antibodies to proteins which are internalized, proteins which target an intracellular site, and the like.
[0103] The pharmaceutical compositions of the invention may be administered in pharmaceutically suitable preparations.
[0104] Such preparations may usually comprise pharmaceutically suitable concentrations of salts, buffering substances, preservatives, carriers, supplementary immunity-enhancing substances such as adjuvants, CpG oligonucleotides, cytokines, chemokines, saponin, GM-CSF and/or RNA and, where appropriate, other therapeutic agents.
[0105] The therapeutic agents of the invention may be administered in any conventional way, including by injection or by infusion. The administration may be carried out, for example, orally, intravenously, intraperitoneally, intramuscularly, subcutaneously, or transdermally. Therapeutical administration of anti-bodies is preferably carried out by way of a lung aerosol. Antisense nucleic acids are preferably administered by slow intravenous administration.
[0106] The compositions of the invention are administered in effective amounts. An “effective amount” relates to the amount which, alone or together with further doses, achieves a desired response or a desired effect. In the case of treatment of a particular disease or of a particular condition, the desired response preferably relates to inhibition of the course of the disease. This includes slowing down the progression of the disease and in particular stopping or reversing said progression of the disease. The desired response on treatment of a disease or of a condition may also be that of delaying the onset or preventing the onset of said disease or condition.
[0107] An effective amount of a composition of the invention depends on the condition to be treated, the severity of the disease, the individual patient's parameters, including age, physiological condition, height and weight, the duration of the treatment, the nature of a concomitant therapy (if present), the specific administration route and similar factors.
[0108] The pharmaceutical compositions of the invention are preferably sterile and comprise an effective amount of the therapeutically active substance to generate the desired response or the desired effect.
[0109] The doses of the compositions of the invention which are administered may depend on various parameters such as the mode of administration, the patient's condition, the desired administration period, etc. In the case where a patient's response is inadequate with an initial dose, it is possible to employ higher doses (or effectively higher doses which are achieved by different, more localized administration route).
[0110] In general, doses of from 1 ng to 1 mg, preferably from 10 ng to 100 μg, of peptides and proteins are formulated and administered for a treatment or for generating or increasing an immune response. If it is desired to administer nucleic acids (DNA and RNA), doses of from 1 ng to 0.1 mg are formulated and administered.
[0111] The pharmaceutical compositions of the invention are generally administered in pharmaceutically suitable amounts and in pharmaceutically suitable compositions. The term “pharmaceutically suitable” relates to a nontoxic material which does not interact with the effect of the active ingredient of the pharmaceutical composition. Such preparations may usually comprise salts, buffering substances, preservatives, carriers and, where appropriate, other therapeutic agents. When used in medicine, the salts should be pharmaceutically suitable. Non-pharmaceutically suitable salts may, however, be used to prepare pharmaceutically suitable salts thereof and are encompassed by the invention. Such pharmacologically and pharmaceutically suitable salts include in a non-limiting manner those prepared from the following acids: hydrochloric, hydrobromic, sulfuric, nitric, phosphoric, maleic, acetic, salicylic, citric, formic, malonic, succinic acids and the like. Pharmaceutically suitable salts may also be prepared as alkali metal or alkaline earth metal salts such as sodium, potassium or calcium salts.
[0112] A pharmaceutical composition of the invention may comprise a pharmaceutically suitable carrier. The term “pharmaceutically suitable carrier” relates according to the invention to one or more compatible solid or liquid fillers, diluents or capsule substances which are suitable for administration to a human. The term “carrier” relates to an organic or inorganic component, natural or synthetic in nature, in which the active component is combined in order to facilitate application. The components of the pharmaceutical composition of the invention are usually such that no interaction which substantially impairs the desired pharmaceutical efficacy occurs.
[0113] The pharmaceutical compositions of the invention may include suitable buffering substances such as acetic acid in a salt, citric acid in a salt, boric acid in a salt and phosphoric acid in a salt.
[0114] The pharmaceutical compositions may also include, where appropriate, suitable preservatives such as benzalkonium chloride, chlorobutanol, parabens and thimerosal.
[0115] The pharmaceutical compositions are usually presented in a unit dose form and can be produced in a manner known per se. Pharmaceutical compositions of the invention may be, for example, in the form of capsules, tablets, lozenges, suspensions, syrups, elixirs or as emulsion.
[0116] Compositions suitable for parenteral administration usually comprise a sterile aqueous or nonaqueous preparation of the agent, which is preferably isotonic with the recipient's blood. Examples of suitable carriers and solvents are Ringer's solution and isotonic sodium chloride solution. In addition, sterile, fixed oils are usually employed as dissolving or suspending medium.
[0117] The present invention is described in detail by the following figures and examples which serve exclusively for illustration purposes and are not to be understood as limiting. Further embodiments which are likewise encompassed by the invention are accessible to the skilled worker on the basis of the description and the examples.
FIGURES
[0118] FIG. 1 . Northern blot analysis using an EDI-3-specific probe
[0119] RNA was obtained from testis, skeletal muscle, liver, lung, spleen, brain and heart (lanes 1-8). Expression of EDI-3 transcript was found in testis (lane 1), skeletal muscle (lane 3) and heart (lane 8).
[0120] FIG. 2 . Expression of EDI-3 in primary endometrial carcinomas
[0121] Expression was found to be elevated by a factor of 6.4 in metastasizing tumors in comparison with non-metastasizing tumors (p≦0.001; Mann-Whitney test, double-sided). Only patients observed over a period of at least 5 years were included. However, a difference regarding expression of EDI-3 is also obtained when all 57 patients, also including those observed over periods shorter than 5 years are included (p<0.001, data not shown). The horizontal line in the center of a box indicates the median of the sample. The edges of a box indicate the 25th and 75th percentiles. The whiskers indicate the range of values within 1.5 box lengths.
[0122] FIG. 3 . Confirmation experiment using a second primer pair for quantifying EDI-3 mRNA expression
[0123] Primer pair No. 1 amplifies a fragment between by positions 2872 and 3172, while primer pair No. 2 results in amplification between by positions 3161 and 3362. Quantitative PCR produced a correlation with p<0.001 and R=0.824.
[0124] FIG. 4 . Confirmation experiment using a second primer pair for quantifying EDI-3 mRNA expression
[0125] Similarly to the results obtained with the first primer pair, higher expression of EDI-3 was found in metastasizing tumors in comparison with non-metastasizing tumors (p<0.001, Mann-Whitney test, double sided). Only patients observed over a period of at least five years were taken into account. The horizontal line in the center of a box indicates the median of the sample. The edges of a box mark the 25th and 75th percentiles. The whiskers indicate the range of values within 1.5 box lengths.
[0126] FIG. 5 . Kaplan-Meier analysis of the association between expression of the EDI-3 transcript and the time span until a recurrence upon resection of endometrial cancer tissue
[0127] EDI-3 expression was dichotomized using the 75% percentile (p=0.0023, logrank test).
[0128] FIG. 6 . Kaplan-Meier analysis of the association between expression of the EDI-3 transcript and the time span until a recurrence as a function of the FIGO stage
[0129] EDI-3 expression was dichotomized using the 75% percentile.
[0130] FIG. 7 . Confirmation experiment using a second primer pair for quantifying EDI-3 mRNA expression
[0131] Similarly to the results obtained with the first primer pair, the time span until the occurrence of a recurrence was longer for patients with low EDI-3 expression in comparison with patients with high EDI-3 expression upon resection of endometrial cancer tissue. EDI-3 was dichotomized at the 75% percentile (p<0.001, logrank test).
EXAMPLES
Example 1
Patients and Tissue Samples
[0132] Between 1985 and 2000, 269 patients with histologically confirmed cancer of the endometrium were treated in the department of obstetrics and gynecology at the University Hospital in Mainz, Germany.
[0133] High-quality RNA was obtainable from only 63 of these patients for three reasons: (i) parts of the tumor samples used for RNA analysis were additionally examined histologically. If the fraction of tumor cells was less than 95%, the sample was not included in the present study. (ii) It was not possible to freeze any tissue from some patients with small tumors. (iii) The quality of some RNA samples was not sufficient based on the ratio of 28S and 18S bands, or expression of the constitutive huPO (human phosphoprotein) gene was too low (Mohrmann G. et al., Int. J. Cancer, in press, 2005). Based on information from clinical records, including surgery reports and pathological reports, a database was generated. The histological tumor type and grade, the weight, height and age of the patients, diabetes mellitus, the FIGO stage, the type of a surgery and the pathological TNM classification were included. The FIGO stage followed the surgical stage determination system for endometrial carcinomas from 1988 (Creasman W T, Gynecol Oncol 1989; 35: 125-7). The body mass index (BMI) was calculated using the formula BMI=[weight/(height) 2 ]. The recurrence-free time was calculated as the difference between the date of a surgical treatment and the date of a documentation of a recurrence. Recurrences developed due to new tumor growth in paraaortic lymph nodes, pelvis, bones, lung, liver and vagina. All histological samples were evaluated by an experienced pathologist. All tumors were classified according to the WHO/ISGPY classification (Scully R E et al., International Classification and Histologic Typing of Female Genital Tract Tumours. Springer: New York, 1994). The tumor grade was determined according to Kurman et al. (Kurman R J et al., In: Kurman R J, ed. Blaustein's Pathology of the Female Genital Tract, 4th edn. Springer: New York, 1994, 439-86), taking into account structural features and core features. The depth of invasion was classified according to Sevin and Angioli (Sevin B-U, Angioli R. Uterine Corpus: Multimodality Therapy in Gynecologic Oncology. Thieme: New York, 1996) as a function of infiltration of the inner, center and outer third of the myometrium. For RNA isolation, only histologically controlled tumor samples containing at least 95% tumor cells without non-neoplastic endometrium or myometrium were included in the study. A standard surgical procedure was abdominal hysterectomy and bilateral salpingo ovariectomy. Lymph nodes were dissected in cases in which intrasurgical frozen sections showed infiltration of the outer third of the myometrium and also in cases with cervical involvement, depending on factors of general morbidity of the patient.
[0134] Among the 63 patients with available RNA of high quality, three pairs of patients with identical FIGO stage, grade, histopathological tumor type, type of surgery, menopausal state, depth of invasion into the myometrium, and a similar body mass index were selected. These pairs comprised in each case one patient who developed metastases within five years after surgery and another patient who was not found to have any metastases within the observation period of at least five years. The six connected patients (“screening set of tumors”) were used for identifying differentially expressed genes.
[0135] The remaining 57 patients served as “validation set” and comprised 13 patients who developed metastases later, while the other patients remained tumor-free. The “validation set” was used in order to address two questions with regard to candidate genes which had been identified in the “screening set” of tumors: (i) did primary tumors of patients who later developed metastases show higher expression of a candidate gene than patients without metastases? (ii) were candidate genes identified in the “screening set of tumors”, which were associated with the period until a recurrence in a multivariate analysis? The patients' characteristics are summarized in table 1.
[0000]
TABLE 1
Properties of the “validation set” of patients
with primary endometrial carcinomas
Primary endometrial carcinomas (n = 57)
Number
evaluated
Not
(n = 57)
%
analyzable
FIGO stage
1
Stage I
35
62.5
Stage II
7
12.5
Stage III
11
19.6
Stage IV
3
5.4
Histological grade
2
Grade I
18
32.7
Grade II
23
41.8
Grade III
14
25.5
Depth of invasion 1
0
low
21
36.8
high
36
63.2
Metastasis 2
2
No
42
76.4
Yes
13
23.6
Menopausal status
0
pre
6
10.5
post
51
89.5
Age at surgery
68.5 ± 11.5
(years, average ±
standard deviation)
Height
163 ± 5.2
(cm, average ±
standard deviation)
Weight
79.5 ± 16.9
(kg, average ±
standard deviation)
1 Depth of invasion was classified as low (infiltration of no more than the inner third of the myometrium) and high (infiltration of the center and outer thirds of the myometrium).
2 Metastasis: After the primary tumor had been removed by standard surgery (abdominal hysterectomy and bilateral salpingo ovariectomy), two classes were distinguished: (i) “no metastasis”, if the patient remained tumor-free, (ii) “metastasis”, if renewed tumor growth was found at any of the following sites: paraaortic lymph nodes, pelvis, bones, lung, liver or vagina.
Example 2
Differential Display
[0136] RNA from frozen tissue was isolated using a commercially available kit (MidiKit, Qiagen, Hilden, Germany). The quality of the isolated RNA was evaluated by way of the ratio of the 28S and 18S bands on a 1% agarose gel and by way of expression of the constitutive huPO gene, as described earlier (Mohrmann G et al., Int. J. Cancer, in press, 2005). The concentrations of the isolated RNA were determined spectrophotometrically. Reverse transcription was carried out using the Delta™ Differential Display Kit (Clontech, Heidelberg, Germany). Amplification was obtained using the P and T primers depicted below (Arbitrary Primer, Clontech, Heidelberg, Germany):
[0000]
P primers
P 1: 5′-ATTAACCCTCACTAAATGCTGGGGA-3′
P 2: 5′-ATTAACCCTCACTAAATCGGTCATAG-3′
P 3: 5′-ATTAACCCTCACTAAATGCTGGTGG-3′
P 4: 5′-ATTAACCCTCACTAAATGCTGGTAG-3′
P 5: 5′-ATTAACCCTCACTAAAGATCTGACTG-3′
P 6: 5′-ATTAACCCTCACTAAATGCTGGGTG-3′
P 7: 5′-ATTAACCCTCACTAAATGCTOTATG-3′
P 8: 5′-ATTAACCCTCACTAAATGGAGCTGG-3′
P 9: 5s-ATTAACCCTCACTAAATGTGGCAGG-3′
P10: 5′-ATTAACCCTCACTAAAGCACCGTCC-3′
T primers
T 1: 5′-CATTATGCTGAGTGATATCTTTTTTTTTAA-3′
T 2: 5′-CATTATGCTGAGTGATATCTTTTTTTTTAC-3′
T 3: 5′-CATTATGCTGAGTGATATCTTTTTTTTTAG-3′
T 4: 5′-CATTATGCTGAGTGATATCTTTTTTTTTCA-3′
T 5: 5′-CATTATGCTGAGTGATATCTTTTTTTTTCC-3′
T 6: 5′-CATTATGCTGAGTGATATCTTTTTTTTTCG-3′
T 7: 5′-CATTATGCTGAGTGATATCTTTTTTTTTGA-3′
T 8: 5′-CATTATGCTGAGTGATATCTTTTTTTTTGC-3′
T 9: 5′-CATTATGCTGAGTGATATCTTTTTTTTTGG-3′
[0137] The products of the first amplification were fractionated on 8% strength denaturing polyacrylamide gels and visualized by silver staining using the Rapid-Silver Stain Kit (ICN Biomedicals, Ohio, USA). Bands which were visible in samples of patients with metastases but which were absent in samples of patients with non-metastasizing tumors were excised, and the DNA was purified using the QiaExIIKit (Qiagen, Hilden, Germany). In order to prepare enough DNA for sequencing, the purified product was amplified again with the aid of the same primers used for identification. After purification by means of QIAquick columns (Qiagen, Hilden, Germany), the DNA sequence was determined by cyclic sequencing.
[0138] A differential display study of the “screening set of tumors” resulted in the identification of three transcripts, namely EDI-1, EDI-2 and EDI-3, which were present in tumors forming metastases, but were not expressed in non-metastasizing endometrial carcinomas.
[0139] EDI-1 was found by means of the Clontech primers P 3 and T 3 and was 260 by in length in the polyacrylamide gel. After reamplification, purification and sequencing with the aid of the P 3 primer, the nucleic acid sequence depicted in SEQ ID NO: 1 was obtained.
[0140] EDI-2 was found by means of the Clontech primers P 2 and T 5 and was 190 by in length in the polyacrylamide gel. After reamplification, purification and sequencing with the aid of the Clontech P 2 primer, the nucleic acid sequence depicted in SEQ ID NO: 2 was obtained.
[0141] EDI-3 was obtained by means of the Clontech primers P 3 and T 3 and was 270 by in length in the polyacrylamide gel. After reamplification, purification and sequencing with the aid of the Clontech P 3 primer, the nucleic acid sequence depicted in SEQ ID NO: 3 was obtained.
[0142] The EDI-3 nucleic acid fragment sequenced has homology to a functionally not yet characterized transcript of 5444 by (accession number AL109935.39.1.178601, SEQ ID NO: 7) containing a predicted open reading frame of 2016 bp. According to database information, the corresponding gene consists of 20 exons and is located on the short arm of chromosome 20 in the p13 band. Northern blot analysis confirmed the expected transcript size ( FIG. 1 ).
Example 3
Quantitative RT-PCR
[0143] TaqMan analysis was carried out as described recently (Mohrmann G et al., Int. J. Cancer, in press, 2005). Briefly, total RNA was isolated from tumor tissue using the RNeasy Mini Kit (Qiagen, Hilden, Germany) and quantified by measuring the optical density at 260 nm. Two μg of total RNA were used for a cDNA synthesis mixture containing 2.5 μl of MultiScribe reverse transcriptase (50 U/μl, Applied Biosystems), 10 μl of RT buffer, 22 μl of 25 mM MgCl 2 , 20 μl of dNTP mix (Applied Biosystems), 2 μl of RNase inhibitor (20 U/μl, Applied Biosystems), 5 μl of random hexamers (50 μM, Applied Biosystems) in a total volume of 100 μl. The mixture was incubated at 25° C. for 2 minutes, at 48° C. for 30 minutes, and the enzyme was inactivated at 95° C. for 5 minutes. All cDNAs were diluted by adding 150 μl of DEPC-treated water and stored at −20° C. A quantitative PCR analysis made use of the Taq-Man™ PCR technology (Gene Amp 5700 sequence detection system, ABI, Weiterstadt, Germany). A PCR was carried out in a volume of 25 μl with 12.5 μl of SYBR GREEN PCR master mix (including enzyme buffer, fluorescent dye and nucleotides, Applied Biosystems), 5 μM of each primer (2.5 μl, 10 mM), 2.5 μl of DEPC-treated water and 5 μl of cDNA template. Two primer pairs were used for EDI-3 analysis: (i) 5′-TTTCA AAATG CTGCA GGGTA AT-3′ and 5′-ACCCA CAAAG CAACA GTGTG TA-3′, (ii) 5′-CACAA TCTGC TTCTA ATCCA AGAA-3′ and 5′-TGCTT TGTGG GTTTG TTTTG TA-3′. The PCR comprised preincubation at 50° C. for 2 minutes, followed by denaturation at 95° C. for 10 minutes. 40 cycles were carried out, including denaturation at 95° C. for 15 seconds, hybridization at 60° C. for 60 seconds and elongation at 72° C. for 30 seconds. The reaction was followed by the dissociation protocol, whereby the range between 60 and 94° C. was studied. Emission ranges of the fluorescent dye were measured in real time during the PCR, and relative mRNA quantification values were obtained from the threshold cycle number from which the increase in the signal associated with exponential growth of PCR product was detectable. The sequence detection system software, version 1.6 (ABI, Weiterstadt, Germany) was used. Quantification was normalized using the constitutive huPO (human phosphoprotein) gene according to Vlachtsis et al. (Vlachtsis K et al., Oncol Rep. 9: 1133-8, 2002). A negative control without reverse transcriptase was included in all PCR analyses.
[0144] Using the “validation set of carcinomas”, it was investigated whether it was possible to confirm the difference regarding EDI-3 expression, found in the “screening set of tumors”. A quantitative RT-PCR indicated increased EDI-3 expression by a factor of 6.4 in metastasizing endometrial carcinomas in comparison with non-metastasizing endometrial carcinomas (p<0.001, FIG. 2 ). Similar results were obtained in an independent study of the same RNA species using a second primer pair ( FIGS. 3 and 4 ).
Example 4
Expression of EDI-3 Indicates Recurrence-Free Survival
[0145] If EDI-3 expression is associated with a formation of metastases, EDI-3 could be assumed to be an indicator for the absence of a recurrence. Expression of EDI-3 (dichotomized at the 75% percentile) was indeed associated with a recurrence-free survival ( FIG. 5 ). The average time span until a recurrence was 1.47 years in the case of patients expressing large amounts of EDI-3. In contrast, 79% of patients with low EDI-3 expression were tumor-free 5 years after surgery (p=0.0023). Using the proportional hazards model, EDI-3 was significant in a univariate analysis (RR=4.3, P=0.002), and in a multivariate step-up regression analysis with the FIGO stage (I, II versus III, IV), an age of over 70 years, diabetes mellitus (y/n), grading (1, 2 versus 3) and the depth of invasion into the myometrium (0-2 mm versus 3+ mm) as covariates (RR=3.6, P=0.012). Only EDI-3 expression and the FIGO stage were prognostic in a multivariate analysis (table 2).
[0000]
TABLE 2
Association of EDI-3 expression with tumor-
free survival in 57 patients with primary cancer of the
endometrium (“validation set of tumors”), using the
univariate and multivariate proportional hazards model
(Cox analysis)
Relative
95% confidence
Factor
risk
interval
p value
Univariate analysis
EDI-3 mRNA
4.3
1.7-11.0
0.002
Multivariate analysis
Adjusted to FIGO stage (I, II vs. III, IV), grading (1,
2 vs. 3), depth of invasion (0-2 mm vs 3+ mm), age
(under versus over 70 years) and diabetes mellitus
EDI-3 mRNA
3.6
1.3-9.7
0.012
FIGO stage (stage
5.1
1.8-14.0
0.002
I, II vs III, IV)
[0146] An adjustment with respect to the FIGO stage could be problematic due to a possible violation of the proportional hazards assumption on which the Cox model is based, and the small sample size. However, the effect of EDI-3 remains significant, if the FIGO stage is included as a factor in the Cox model (p=0.012), as well as if the FIGO stage is used for stratification, assuming different hazard functions for a restricted (FIGO I, II) and advanced (FIGO III, IV) disease (p<0.001, FIG. 6 ). In order to test reproducibility of the quantitative RT-PCR, the same mRNA species were additionally studied using a second primer pair directed to a region of the EDI-3 transcript located further downstream. Data obtained with the second primer pair corresponded to those of the first primer pair (p<0.001, R=0.824) and confirmed a relationship between EDI-3 expression and a recurrence-free survival (table 3, FIG. 7 ).
[0000]
TABLE 3
Confirmation experiment using a second primer
pair for quantifying EDI-3 mRNA expression. Similarly
to the results obtained with the first primer pair,
expression of the EDI-3 transcript was associated with
tumor-free survival in 57 patients with primary cancer
of the endometrium (“validation set of tumors”), using
the univariate and multivariate proportional hazards
model (Cox analysis)
Relative
95% confidence
Factor
risk
interval
p value
Univariate analysis
EDI-3 mRNA
7.9
3.0-21.3
<0.001
Multivariate analysis
Adjusted to FIGO stage (I, II vs. III, IV), grading (1,
2 vs. 3), depth of invasion (0-2 mm vs 3+ mm), age
(under versus over 70 years) and diabetes mellitus
EDI-3 mRNA
7.3
2.7-19.9
<0.001
|
The invention relates to the diagnosis, prognosis, monitoring, and treatment of neoplastic diseases such as tumor diseases, especially tumor diseases of the endometrium and the metastases thereof.
| 2
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is related to a method and system for assuring the proper alignment of multiple power transmission pulleys, such as those typically found in the front end accessory drives of an automotive internal combustion engines.
[0003] 2. Related Art
[0004] Modern automotive internal combustion engines typically utilize a number of belt driven accessories, such as a power steering pump, an air injection pump, an air conditioning compressor, an a/c generator, and a water or coolant pump. Such accessories are commonly driven by a single flat elastomeric belt, sometimes termed a “serpentine” belt. Serpentine belts typically contact pulleys on both sides of the belt; that is, the belt may be ribbed on one side to fit in grooves formed on certain of the pulleys, while running on the back side of other pulleys having smooth surfaces for engaging the belt.
[0005] Proper alignment of drive pulleys is essential if the drive belt is to provide adequate life and reliability. If the alignment of the pulleys is not correct, a belt may be thrown from the pulleys, which could have the effect of causing the engine to stop operating, were the engine to overheat, or were the a/c generator to stop rotating for a sufficient amount of time for the battery to discharge to the point where the engine's electrical needs could no longer be supported. Another problem associated with misaligned pulleys is one of excessive noise, which may cause dissatisfaction in the ranks of motorists experiencing this problem, as well as concomitant expense to the manufacturer and/or the motorist to repair the cause of the excessive noise or squeaking.
[0006] U.S. Pat. No. 5,987,762 discloses a pulley alignment gauge which, although marginally useful, is not particularly suited to determining whether companion pulleys are both coplanar and operating upon axes which are mutually parallel, because the emitted light from the device disclosed in the '762 patent is a coherent beam, rather than a plane of light.
[0007] It would be desirable to provide a system and method for easily checking the alignment of a multiplicity of drive pulleys associated particularly with an automotive engine so as to ensure proper drive belt life, proper engine integrity, and a low belt noise signature.
SUMMARY OF THE INVENTION
[0008] According to an aspect of the present invention, a method for verifying the spatial or planar alignment of a number of power transmission pulleys includes positioning a planar light source at a reference location associated with the power transmission pulleys, and allowing an illumination plane emitted by the planar light source to impinge upon the pulleys. The method also includes verifying correct alignment of the pulleys by comparing the locus of the intersection of the illumination plane with at least one of the pulleys with a locus of intersection of the illumination plane with at least another one of the pulleys.
[0009] According to another aspect of the present invention, a planar light source is preferably positioned so as to cause the illumination plane to impinge upon the pulleys in a direction normal to the axes of rotation of the pulleys. The illumination plane itself originates within the planar light source at a single point which is operatively associated with a reference location.
[0010] According to another aspect of the present invention, the planar light source preferably comprises a light source distributed by a rotating mirror. The light source may include a laser or other type of light generating device.
[0011] According to another aspect of the present invention, the loci of intersection of the illumination plane with pulleys are compared by determining whether offsets exist from a preselected nominal location for such intersections on each pulley.
[0012] According to another aspect of the present invention, a reference location for positioning a planar light source may be associated with a front cover of an automotive internal combustion engine.
[0013] According to another aspect of the present invention, a system for verifying the planar alignment of a number of power transmission pulleys includes a planar light source for producing an illumination plane, and at least one reference location, configured as a locating surface associated with the power transmission pulleys, for locating the planar light source so as to permit an illumination plane emitted by the planar light source to impinge upon the power transmission pulleys at predetermined locations upon the pulleys. The planar light source may either be held manually in contact with the locating surface, or it could be mounted by means of a threaded fastener or other device upon the locating surface.
[0014] It is an advantage of a method and system according to the present invention that coplanar alignment of a number of driving and driven pulleys may be assessed easily without resort to cumbersome mechanical measurement means.
[0015] It is another advantage of a method and system according to the present invention that the method may be employed easily and with in-use vehicles at dealerships and other repair facilities.
[0016] It is yet another advantage according a method and system of the present invention that collision damaged engines may be repaired properly because misaligned pulleys are readily detectable with the present method and system, without the need for extensive personnel training or instrumentation.
[0017] It is another advantage of a method and system according to the present invention that the method may be employed with not only elastomeric belt pulleys, but also with metallic and non-metallic chain pulleys commonly referred to as sprockets.
[0018] Other advantages, as well as features of the present invention, will become apparent to the reader of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a perspective view of an engine having a front end accessory drive which is being analyzed by a laser illuminator according to the present invention.
[0020] FIG. 2 is a sectional view of a planar light source according to an aspect of the present invention.
[0021] FIG. 3 is a schematic representation of a process for employing a planar light source to detect an out of alignment pulley condition.
[0022] FIG. 4 is an elevational view of a modified planar light source according to an aspect of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] Referring to the Figures, wherein like numerals indicate like or corresponding parts throughout the several views, as shown in FIG. 1 , an engine, 10 , has a variety of accessories including an a/c generator, 14 , having a pulley, 18 , and a tensioner pulley, 22 , for tensioning a serpentine belt, 46 . Engine 10 also includes a water pump pulley, 26 , connected with a water pump (not shown), and a power steering pulley, 30 , connected with a power steering pump (not shown). A crank pulley, 34 , which is connected with the engine's crankshaft (not shown) provides power for the accessory drive system.
[0024] The engine of FIG. 1 also includes an air conditioning compressor, 38 , which is driven by a pulley, 42 . Some of the rotating accessories are mounted upon a front cover, 50 , which also contains a locator pad, 54 , for mounting a planar light source, 64 , shown in the various Figures.
[0025] In use, laser illuminator or planar light source 64 creates a plane or sheet of light, 60 , which impinges in a normal direction upon the front edges of all of pulleys 18 , 22 , 26 , 30 , 34 and 42 , thereby providing a visual indication to a mechanic of any pulleys which are either not coplanar, or axially displaced with offsets existing from a predetermined nominal location. In other words, the intersection of the pulleys with illumination plane, 60 , as shown in FIG. 1 is used to determine whether any of the pulleys is not operating in the same plane as other pulleys, or is displaced in any manner from a common plane.
[0026] As shown schematically in FIG. 3 , planar light source 64 , having been mounted to locator pad 54 with a threaded fastener 56 , is emitting a plane of light, 60 , through window 62 . Illumination plane 60 impinges upon pulleys 92 and 96 in a direction normal to the axes of rotation of the pulleys. Illumination plane 60 indicates two different things with respect to pulley 92 . Thus, with position 92 A, pulley 92 is shown as being parallel with pulley 96 , but with position 92 B, pulley 92 is not parallel with pulley 96 , and as a consequence, illumination plane 60 does not illuminate a portion of the outer rim of pulley 92 . This uneven illumination is a telltale sign that pulley 92 is not parallel with pulley 96 .
[0027] FIG. 2 shows a planar light source 64 , having an on/off button, 66 , and two batteries, 68 , driving a laser light source 72 , and a motor, 88 . When on/off button 66 is placed in the “on” position, energy is provided to a laser light source, 72 , as well as to a motor, 88 , thereby causing mirror 84 to rotate at a high speed. This causes an illumination plane, (also shown at 60 in FIGS. 1 and 3 ), to be emitted by planar light source 64 from a single point. Notice also in FIG. 2 that planar light source 64 is in contact with locator pad 54 formed in front cover 50 . The precise positioning of planar light source 64 provided by its location upon pad 54 determines a precise dimension for the location of illumination plane 60 , which as noted above, shines upon various pulleys such as 18 , 30 , 34 etc. in a precise location. In other words, a pre-selected nominal location is selected for the intersection of illumination plane 60 with each of the pulleys. This pre-selected nominal location may be either an outer rim of any particular pulley, or an inner rib on the pulley, it being understood that what is important is that a common feature be selected for each of the pulleys. In the event that an outer rim is selected on a pulley, it is possible to use the present method and system even with drive belt 46 installed in some engines. With other engines it will be necessary to remove the drive belt to perform a test using the present device. Those skilled in the art will appreciate in view of this disclosure that planar light source 64 may be powered alternatively by single or multiple power sources such as either the illustrated internal batteries, or by a vehicular power system, or by conventional commercial power.
[0028] Once planar light source 64 is switched on, the locus of intersection of illumination plane 60 with at least one of the pulleys may be compared with the loci of intersection of other of the pulleys. By systematically working through the complete assemblage of pulleys a mechanic may determine if any of the pulleys is not coplanar with the other pulleys.
[0029] Those skilled in the art will appreciate in view of this disclosure that a planar light source according to the present invention may be constituted either as a laser light source, or may use other type s of illuminating devices. Furthermore, those skilled in the art will appreciate that multiple locator pads 54 may be provided upon either the front cover of an engine or a cylinder block of the engine, or upon yet other engine structural features, so as to permit ready identification of misaligned pulleys. Finally, with the threaded fastener 56 shown in FIG. 3 , it is possible to mount planar light source 64 to an engine and then start the engine to safely and conveniently obtain a view of the dynamic operation of drive belt 46 and the various pulleys of the accessory drive system.
[0030] In the embodiment of FIG. 4 , a micrometer adjustment, 104 , 108 is provided for light source 100 . As knob 104 is rotated manually with respect to base 102 , the distance, L, between light window 110 and base 102 is adjusted as barrel 106 moves either closer to, or further away from, base 102 . The correct placement of any particular pulley may be verified with reference to locator pad 54 by simple manual manipulation of the micrometer adjustment sufficient to bring any particular pulley into registry with illumination plane 60 .
[0031] The foregoing invention has been described in accordance with the relevant legal standards, thus the description is exemplary rather than limiting in nature. Variations and modifications to the disclosed embodiment may become apparent to those skilled in the art and fall within the scope of the invention. Accordingly the scope of legal protection afforded this invention can only be determined by studying the following claims.
|
A method and system for verifying the spatial and coplanar alignment of a number of power transmission pulleys, particularly as used with an automotive internal combustion engine. A planar light source is provided at a reference location associated with the power transmission pulleys, and an illumination plane emitted by the planar light source is allowed to impinge upon the pulleys. Then, correct alignment of the pulleys is determined by comparing the locus of the intersection of the illumination plane with at least one of the pulleys with a locus of intersection of the illumination plane with another of the pulleys.
| 6
|
BACKGROUND OF THE INVENTION
FIELD OF THE INVENTION
This invention relates to the insulation of structures and more particularly, to a ceiling insulation structure for attics which incorporates a water vapor-permeable film or membrane installed over ceiling joists supporting a ceiling structure and covering insulation disposed between the ceiling joists, which film substantially prevents the circulation of air through the insulation in the attic. The invention further relates to a method for installing the film in the ceiling insulation structure in order to better increase the efficiency of the insulation.
The ceiling insulation structure improvement and method of this invention is characterized in one embodiment by a relatively thin, moisture-permeable film or membrane situated over insulation, which insulation is supported by the ceiling structure between the ceiling joists of an attic, in order to substantially prevent air from circulating through the insulation to reduce the efficiency of the insulation. Such ceiling structures are typically characterized by a "dry wall" or "sheetrock" material which serves to partition the living area of a structure from the attic. In a preferred embodiment of the invention a 2 mil polyethylene membrane or film is placed over insulation material provided in the form of batts or particulate, blown insulation placed on the ceiling sheet rock and between the ceiling joists of an attic in order to isolate the insulation from air which normally circulates through the attic. In a most preferred embodiment of the invention the membrane is secured at the outer perimeter of the attic near the point where the roof line meets the ceiling joists and is maintained in unsealed, but lapped condition as it crosses the center portion of the attic. In this manner, air which circulates through the attic is not permitted to enter the insulation to provide a conduit for heat movement from the attic of the structure to the interior thereof and from the interior into the attic, as the case may be.
Conventional insulating techniques have taken the form of placing batts or blown, loose-fill insulation between the ceiling joists of an attic in a structure in order to provide a medium which contains air pockets designed to minimize the passage of heat from the attic into the interior of the structure and from the interior back into the attic. The efficiency of such insulation is commonly measured in terms of an "R" factor, which depends upon the character and thickness of the insulation. Conventional insulation installation frequently includes the use of a "vapor barrier" sheeting positioned between the insulation and the dry wall or sheetrock or alternative ceiling covering which separates the rooms of the structure from the attic itself and serves both as a support for the insulation and also as an insulating component. The insulation material such as fiberglass or other material capable of trapping air is placed on the sheetrock and between the ceiling joists in the form of batts, rolled strips or in particulate form, by way of blowing, and the structure is considered to be well insulated, depending upon the thickness and character of the insulation installed. It has surprisingly been found that the insulation installed in this manner has little effect upon the heat loss and gain of a structure through the attic area under a variety of weather conditions and temperatures. Experimentation has shown that use of a "vapor barrier" installed in the manner described above does little to aid the insulation process, since air circulation in the attic destroys much of the efficiency of the insulation and in many cases, the sheetrock ceiling itself is the only effective insulating barrier between the interior of the structure and the attic. It has also been determined that the use of a membrane of selected thickness and character installed on top of the insulation and ceiling joists of an attic does not, as widely believed, trap and retain excessive quantities of moisture between the membrane and the insulation and degrade the sheetrock. In contrast, it has been found that the moisture is able to readily move through the insulation and through certain moisture-permeable films and membranes and escape into the attic itself, where the moisture is removed by ventilators, with no adverse effect on either the insulation or the underlying sheetrock. The addition of such a moisture-permeable membrane or film has been found to reduce heating and cooling costs by as much as 59% and represents a significant increase in the efficiency of the underlying insulation. Since it has been estimated that 80% to 90% of the heat gain or loss in a ceiling structure having an attic takes place through the attic, the ceiling insulation structure and method of this invention becomes extremely significant in energy conservation efforts.
Many efforts have been made in recent years to improve the insulating efficiency in structures and typical of these efforts is the "Building Insulation and Method of Installation" disclosed in U.S. Pat. No. 4,155,208, to John A. Shanabarger. The insulation and method of this invention includes use of a sheet of heavy plastic and cooperating elongated plastic bags which fit between the studs of a wall structure and conform to the insulating spaces between the studs to insulate the walls. The bags are resilient and can be expanded volumetrically to substantially fully occupy the spaces between the studs and can be attached to the studs by means of stapling, or by other techniques. U.S. Pat. No. 3,298,150, to D.E. Ahlquist, discloses "Wall Insulation Structures and Method of Using Same", and describes insulation for walls and other surfaces which are characterized by multiple blocks of insulating material contained in an envelope having side panels which are disposed along the walls to insulate the walls. Another insulating wall structure is disclosed in U.S. Pat. No. 3,641,724, to James Palmer, which structure includes an integral box construction built directly into a selected wall section and further includes interior foam materials such as various urethanes, to provide the necessary insulation. An "Insulated Roof" is disclosed in U.S. Pat. No. 4,147,003, to Robert J. Alderman, which roof includes a reel of flexible sheet material mounted on a support frame and situated over a space between adjacent roof purlins. This framework is moved along the purlins and the sheet material is progressively unrolled, formed and guided by the framework down into the space between the adjacent purlins to create a trough in the spaces between the purlins. Insulation material is placed in the trough on top of the sheet material in order to insulate the roof. Another insulated roof structure is disclosed in U.S. Pat. No. 4,047,346, also to Robert J. Alderman, which includes a reel of wire mesh and a cooperating reel of sheet material carried by a supporting framework to facilitate progressively unrolling the layers of wire mesh and sheet material for application to the spaces between the roof purlins. Insulation is then placed in the wire and sheet material trough in order to insulate the roof.
It is an object of this invention to provide in one embodiment, a new and improved ceiling insulation structure for insulating the attics of homes, offices and other structures, which improved ceiling insulation structure is characterized by a moisture-permeable film or membrane placed over a mass of insulation disposed between the ceiling joists and resting on the ceiling in the attics, which film serves to minimize air circulation through the insulation.
Another object of this invention is to provide an improvement to the existing insulation in an insulated attic having a layer of sheetrock attached to the bottom of supporting attic ceiling joists and a mass of insulation located between the ceiling joists and supported by the sheetrock, which improvement includes placing a water vapor-permeable film or membrane over the insulation and the ceiling joists in order to minimize the movement of air through the insulation and thereby improve the efficiency of the insulation.
A still further object of the invention is to provide an improved ceiling insulation structure for attics, which includes a water vapor-permeable polyethylene membrane or film of selected thickness covering a quantity of insulation installed on sheetrock between the ceiling joists of the attic, which membrane serves to substantially prevent air from circulating through the insulation and increases the efficiency of the insulation, while allowing moisture to move through the insulation without collecting therein and damaging the insulation or the underlying sheetrock.
Still another object of this invention is to provide a method for increasing the efficiency of insulation in the attics of structures, which method includes the expedient of placing a water vapor-permeable membrane or film over the insulation and the ceiling joists of the attic in order to prevent extensive circulation of air through the insulation.
A still further object of the invention is to provide a method for minimizing the circulation of air and heat through insulation in the attics of structures, which method includes installing a moisture-permeable, plastic membrane or film over the insulation and ceiling joists by securing at least the outer perimeter of the film to the ceiling joists or other structural member in order to substantially isolate the insulation between the ceiling joists.
SUMMARY OF THE INVENTION
These and other objects of the invention are provided in a ceiling insulation structure for enhancing the insulating capability of attics, which includes a water vapor-permeable, thermoplastic membrane of selected thickness positioned over the ceiling joists in the attic and covering insulation provided between the ceiling joists. A method for reducing air flow through insulation in an attic and thereby increasing the efficiency of the insulation, which includes placing a water vapor or moisture-permeable thermoplastic membrane or film of selected thickness over the insulation and the ceiling joists in the attic to substantially isolate the insulation between the ceiling joists.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be better understood by reference to the accompanying drawing wherein:
FIG. 1 is a perspective view, partially in section, of a structure with the attic area open to inspection and illustrating a preferred embodiment of the ceiling insulation structure and method of this invention; and
FIG. 2 is sectional view of a segment of the ceiling insulation structure illustrated in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring initially to FIG. 1 of the drawing a structure 10 is illustrated, with walls 11, a foundation 12 and an attic 6, having roof trusses 7 carrying roof supports 8, supported by ceiling joist supports 9. As illustrated in FIGS. 1 and 2, in a preferred embodiment the ceiling insulation structure of this invention is generally illustrated by reference numeral 1 and includes ceiling joists 2, with a ceiling material 3 attached to the bottom thereof, a quantity of insulation 4 disposed between the ceiling joists 2 and resting on the ceiling material 3 and a transparent film 5, positioned over the ceiling joists 2. The insulation 4 can be applied to the ceiling material 3 and between the ceiling joists 2 by means of a blowing apparatus, in the case of particulate, loose-fill insulation such as fiberglass and the like, or by laying batts between the ceiling joists 2 or by other techniques well known to those skilled in the art. When the insulation is installed as illustrated, a roll 15 of film 5 can be placed in the attic 6 of the structure 10 and a sheet of the film 5 positioned over the insulation 4 and on top of the ceiling joists 2, as illustrated.
Referring again to FIG. 2 of the drawing in a most preferred embodiment of the invention when the roll 15 is deployed to position the film 5 on top of the ceiling joists 2 and over the insulation 4 as illustrated, staples 14 are used to secure the end of the film 5 to the ceiling joists 2 or the ceiling joist supports 9 of the structure 10 or to other structural members in the structure 10, in order to secure the film 5 in the attic 6. Furthermore, as further illustrated in FIG. 2, the insulation 14 illustrated is in the form of batts, with an insulation wrap 13 securing the insulation 4 in a sandwich configuration. It will be appreciated from a further consideration of FIG. 2 that the film 5 can be lapped as it is deployed from the roll 15 in successive sheets in order to cover the entire surface area of the ceiling joists 2 and insulation 4 to minimize the effect of air circulation in the attic and reduce heat transfer through the insulation 4.
Referring again to FIGS. 1 and 2 of the drawing, it will be appreciated that the ends of the film 5 which are adjacent to the ceiling joist supports 9 and the roof supports 8 of roof trusses 7, can be cut or split to accommodate each of the roof supports 8 at the point where the roof supports 8 join ceiling joists 2, in order to cover that portion of insulation 4 which lies at the extremities of the ceiling joists 2. In another most preferred embodiment of the invention the ends, and particularly the split areas of the film 5 are secured to ceiling joist supports 9 and optionally, to the ceiling joists 2, by means of staples 14. While the character and thickness of the film 5 is important only in the sense that it must be capable of allowing water vapor to migrate through the film layer, in a preferred embodiment, the film 5 is characterized by a thickness of from about 0.5 to about 12 mils. In a most preferred embodiment of the invention a polyethylene film 5 having a thickness of from about 1.0 to about 4 mils is most preferred for use in covering the insulation 4 and ceiling joist 2 in the attic 6. However, it will be appreciated by those skilled in the art that substantially any thermoplastic or thermoresin material such as polyethylene, polypropylene and like "plastics" which can be shaped into a relatively thin film or membrane and which allow the migration of water vapor therethrough can be used to cover the insulation 4 and ceiling joist 2 according to the teachings of this invention, to more efficiently insulate the attic 6 of the structure 10. It must be remembered that the ability of the moisture or water vapor to penetrate the film 5 is directly proportional to the thickness of the film 5 chosen.
Various benefits and advantages of the present invention are more readily understood by consideration of the following examples which are merely illustrative and are not intended to limit scope of the invention.
EXAMPLE 1
Several box frames measuring 1 foot on a side in the configuration of a cube were built and were fitted with thermometers for measuring the temperature of the interior of the boxes. Two inches of fiberglass insulation was installed in one of the frames (box 1) on all six sides. Two inches of fiberglass insulation with a polyethylene film or sheath covering the insulation and exposed to the exterior of the second box (box 2) was also provided. Two volumes of five hundred milliters of water were heated to a temperature of 125° F. and one volume was placed in each of two containers and one of the containers was placed in box 1, containing only the fiberglass insulation while the second container was placed in the box 2, containing the fiberglass and polyethylene film combination. The air temperature outside of the boxes was observed to be 30° F. The water was allowed to cool in each of the boxes and the interior temperature of each box was recorded as a function of time. The following table summarizes the results of this EXAMPLE 1:
______________________________________ INSIDE BOX TEMP. (F.°)TIME (MIN.) Box 1 Box 2______________________________________10 58 6820 56 6730 54 6340 50 6060 48 5690 40 48______________________________________
EXAMPLE 2:
This experiment was conducted using the attic of a home located in Shreveport, Louisiana, under various weather conditions. Upon inspection, the attic of the home was provided with nine inches of insulation located between the ceiling joists and resting on a sheetrock ceiling material secured to the bottom of the ceiling joists. The house was certified by Southwestern Electric Power Company for maximum energy efficiency. Temperature measurements in the attic when the attic air space temperature was 125° F. indicated that the temperature beneath the insulation and next to the sheetrock layer was 114° F., for an 11 degree temperature drop through the nine inch insulation layer. The temperature next to the sheetrock inside the house was 82° F., for a 32 degree temperature drop through the sheetrock, indicating that the insulation was providing very little insulating benefit.
A 2 mil film of polyethylene was installed between two of the ceiling joists and over the insulation between these ceiling joists in the attic of the house and the temperature was recorded at various points with a Doric Digital Trendicator furnished by the Department of Energy. At a point between the ceiling joists containing the film and beneath the insulation at the sheetrock layer the temperature was checked and was found to be 92° F., for a 33 degree drop through the insulation and a 10° drop through the sheetrock, indicating a marked increase (threefold) in the efficiency of the insulation when the film was installed. The following table summarizes the results of EXAMPLE 2:
__________________________________________________________________________ TEMP @ BOTTOM OF ROOM TEMP.CHARACTER OF ΔT ACROSS ATTIC AIR INSULATION ADJACENT IN STRUCTUREINSULATION INSULATION (F.°) TEMP (F.°) CEILING (F.°) ADJACENT CEILING__________________________________________________________________________NO FILM 15 40 55 70WITH FILM 22 40 62 70NO FILM 12 50 62 70WITH FILM 18 50 68 70NO FILM 11 125 114 82WITH FILM 33 125 92 82__________________________________________________________________________
EXAMPLE 3:
Another home in Shreveport, La. was provided with a 2 mil sheet of polyethylene over the entire ceiling joist area which contained insulation located between the ceiling joists and resting on the sheetrock ceiling divider. This data was correlated, computed and indicated a 59% reduction in heating and cooling costs and a 35% reduction in total utility costs for the winter of 1981 and 1982. Additional study of data collected in this house in the summer of 1982 and winter of 1982-1983, indicates that the heating and cooling energy usage has been reduced by 50% to 75% due to the installation of the film.
EXAMPLE 4:
One of the questions raised during the experiments conducted with the polyethylene film is that of water collection beneath the film. In order to determine the nature and extent of any such water collection, a box 4 feet square on each side in the configuration of a cube was constructed and the top of the box was constructed similar to that of a home or commercial structure, with one-half inch sheetrock used as a ceiling material and fiberglass batts having a thickness of 8 inches installed over the sheetrock to simulate the attic area. A two mil sheeting of polyethylene was installed over one of the batts and a rack supporting two pans of water and an electric light bulb was placed inside the box. The box was then placed inside a cooler where the temperature was maintained at a temperature of 40° F. and numerous temperature measurements were made and recorded inside the box and at points where the insulation rested on the sheetrock ceiling material.
Initially, tests were conducted using a 300 watt heat lamp directed at the sheetrock inside the box. The temperature beneath the insulation and adjacent the sheetrock was found to be over 100° F. and moisture condensation was noted in both the insulation which was covered by the film and in the insulation which was not so covered. The heat lamp was replaced by a 100 watt light bulb, and the temperature inside the box was noted to be 60° F. A relative humidity reading of 70% was also noted. After approximately 48 hours, the moisture was observed to have evaporated and there was no evidence of condensation in either the insulation covered by the polyethylene film or the bare insulation. The 100 watt light bulb was then replaced by a 200 watt bulb, which raised the temperature inside the box to 74° F. and a relative humidity of 80% was noted. After 72 hours, moisture condensation was observed in the insulation with and without the film covering. This experiment was run several times and it was always observed that the condensation disappeared when the 100 watt light bulb was installed and after a forced dew point condition had been observed. In both cases, the moisture content was higher in the insulation which was not covered by a film than in the insulation covered by the film. It is believed that the air circulation in the insulation from the refrigeration unit in the cooler carried cold air into the insulation which was not covered by the film, thus creating a higher dew point condition.
While the preferred embodiments of the invention have been described above it will be recognized and understood that various modifications may be made therein and the appended claims are intended to cover all such modifications which may fall within the spirit and scope of the invention.
|
A ceiling insulation structure for an attic which includes a "sheetrock" or "dry wall" ceiling carried by attic ceiling joists in spaced relationship, insulating material provided between the ceiling joists and covering the sheetrock and a water vapor-permeable film or membrane of selected thickness covering the insulating material and the ceiling joists to prevent air from circulating through the insulating material and reducing the efficiency of the insulating material. A method for increasing the efficiency of insulating material in an attic which includes covering the insulating material and the ceiling joists with a water vapor-permeable film or membrane of selected thickness.
| 4
|
RELATED APPLICATIONS
Reference may be made to co-pending application (Ser. No. 08/293,121 entitled, "Low Profile Switching Machine", now U.S. Pat. No. 5,494,242, assigned to the assignee of the present invention. Also, reference may be made to co-pending applications (Ser. No. 08/293.126, entitled, "Point Detection and Indication with Latch Out Means") and (Ser. No. 08/293,127, entitled "Switch Machine Cam Bar") that are related to the present application and are commonly owned by applicant's assignee.
BACKGROUND OF THE INVENTION
It is a requirement for operation of a railroad to be able to switch trains from one track to another. A common method of providing the switching capability is to install an electric motor driven switch which functions, by means of a motor driven throw bar or the like to throw switch points so as to control the switching of rolling stock.
Although this type of switching works well for main line and transit operations, for yard applications additional switching features are required. For example, it is common for yard switch machines to have provisions for hand throw to permit local operational personnel to operate the switch.
In the context of operation in very busy railroad yards, in which the railroad stock is being continuously moved in the forward and reverse directions, it is required to move such stock through switches with the switch in the reverse or trailing position. A yard switch machine that will trail without damage is very desirable in that the train operator does not have to stop the train and throw the switch is passage if in the reverse or trailing direction.
For a switch machine with trailing capability, passage of rolling stock through the switch in the reverse or trailing direction will cause the switch to be thrown automatically, that is, without the time delay of a manual switch operation.
However, the traditional or conventional method of providing trailing capability for a switch machine has been to package the required mechanism inside the switch machine. This concept is not desirable for the following reasons: (1) The trailing mechanism is rather large and, as a result, packaging the device inside the switch machine results in either a relatively large profile height for the switch or elimination of other desired switch machine functions. (2) A switch machine with a built in trailing means or mechanism cannot be used for main line and transit operations where trailing is not required. (3) The trailing mechanism, according to conventional construction, has such mechanism built into and integral with a switch machine and is usually packaged on the bottom of the machine to be near the throw bar. Consequently, maintenance and inspection is difficult since the switch machine must be disassembled to reach the interior area occupied by the trailing mechanism.
Accordingly, it is a primary object of the present invention to provide a trailing mechanism that can be used in conjunction with a low profile configuration switch machine. A related object of the present invention is to make the aforesaid trailing mechanism such that it can be placed outside the switch machine configuration.
An ancillary object is to provide flexibility so one can either conjoin the trailing mechanism with the switch machine or not so conjoin. In other words the switch machine stands on its own or can either incorporate or not incorporate the trailing mechanism.
A desirable function of a switch machine or a railroad switch layout is the ability to incorporate lost motion into the trailing mechanism. Switch machines are fixed stroke, or fixed throw mechanisms; they are usually set to the maximum throw that will be required for all switch layouts. A throw of 6.0 inches to 6.5 inches maximum is usually selected. Some switch layouts will require much less throw for the switch layout. A 4.0 inch minimum is common in the industry. Since the traditional switch machine is a fixed throw device set for the maximum throw required, a lost motion means must be provided by either the switch machine or the switch layout itself.
It has been the common practice in the industry to provide the lost motion mechanism in the switch layout and not in the switch machine. This practice results in additional installation cost and maintenance of the lost motion mechanism.
It is therefore, an object of another, different feature of the invention to avoid the additional costs normally involved in installation and maintenance of the lost motion mechanism by, instead, incorporating that mechanism within the trailing mechanism or device.
SUMMARY OF THE INVENTION
It will thus be appreciated that if the purpose of the present invention is to provide a novel arrangement for a switch machine that has the feature of a main line switch layout that may be readily converted to a switch machine with trailing capability by the addition of a retro-fitted trailing module in accordance with the present invention. This trailing module is added to the switch machine or the switch layout simply by means of external bolts, such that the module gives the switch layout trailing capability without the need for replacing or making internal structural modifications to the switch machine.
Briefly defined then, the present invention involves an apparatus for operating railroad switches, including operation in a trailing mode, the arrangement being such that a switch machine has a throw bar for enabling the throwing of switch points that control the switching of rolling stock. The machine also has a throw rod, the throw bar and rod being variably extensively coupled such that when a "wrong direction" load is impressed on the switch points, the throw rod will be moved, but there will not be corresponding movement of the throw bar, and hence no damage will be caused to the motor and other components, take-up space being provided in the trailing mechanism.
Other and further objects, advantages and features of the present invention will be understood by reference to the following specification in conjunction with the annexed drawings, wherein like pans have been given like numbers.
BRIEF DESCRIPTION OF DRAWING
FIG. 1A is a plan view of an exemplary switch layout, particularly illustrating a conventional switch machine connected to an embodiment of the trailing mechanism of the present invention, located as seen.
FIG. 1B is an elevation view of the same layout seen in FIG. 1A.
FIG. 2 is a vertical sectional view of another embodiment of the trailing mechanism.
FIG. 3 is a view of the lost motion means incorporated within the trailing mechanism so as to provide adjustability in making the switch throw compatible with the switch machine throw.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the Figures of the drawing and, in particular, to the FIGS. 1A and 1B, there is shown the general layout, i.e., a switch layout with a first embodiment of the trailing device or mechanism located between rails.
As is well understood, a switch machine 10 is located adjacent a railroad track. A throw bar 12 extends from one side of the switch machine, being operative in conventional fashion to initiate the throwing of conventional switch points. Also seen is a throw rod 14 coupled to the throw bar 12 for extending to the switch points. In the embodiment seen in FIG. 1A, a sync bar 16 makes actual connection to the switch points, being bolted to the throw rod 14, and the trailing mechanism 16. In the embodiment seen in FIGS. 1A and 1B, the throw rod 14 extends into and forms an integral part of the trailing mechanism 16, such part being referred to as a trailing rod 22.
The detailed construction of the trailing mechanism will be described now with reference to FIG. 2, in which an alternate embodiment thereof is provided which is adapted to be slung under the switch machine 14. As seen in FIG. 2, this embodiment of the trailing mechanism 16 is mounted at either end of the switch machine throw bar 12, by means of mounting brackets 18 and mounting clamps 20.
The trailing mechanism 16 is contained within a housing 21 and also enclosed within the housing is the trailing rod 22 which engages with or forms part of the throw rod 14. The trailing rod 22 is configured to have a generally cylindrical shape but to provide a pocket or pockets 23 to retain or detain ball means in the form of first and second balls, 24 and 26, as seen; although, additional balls would be optionally included. The ball means acts to center the trailing rod relative to the trailing device housing. A cam surface or cam surfaces 30 are machined on either side of each pocket to provide trailing operation. Inside the housing are two compression springs 31, one on either side, and ball retainers 34 on either side of the balls. The springs are compressed to center the trailing or throw rod and to preset the desired trailing force.
The normal position of each of the balls, relative to the cam surfaces 30, is in the middle pocket or detent 23. As the switch machine throw bar 12 moves the switch points from normal to reverse without trailing, the trailing device or mechanism 16 is non-operational and the ball means remains in the middle of the cam arrangement.
However, to illustrate a trailing mode, consider the following: with the switch machine throw bar 12 extended to the right, let us assume that a piece of rolling stock produces a left directional load into the trailing mechanism as shown. That is to say, a rolling stock piece proceeds in a "wrong direction"against the setting of the switch points.
What would normally happen in such a situation without the trailing mechanism is that the load, having a force of 1500 lbs. or greater, would have its way; that is, the switch points would be forced in the opposite direction with attendant movement of the throw rod and consequent reverse movement of the parts of the switch machine. Particularly in the event that the motor driver is in a non-operating state, severe damage could result to the motor and many of the components of the switch machine.
However, in the assumed case, that is, with the trailing mechanism as seen in FIG. 2 functioning properly, the effect is that the "left load" causes the trailing rod 22 to be moved to the left and ball means to end up out of its normal position in pocket or detent 23, and into the right curved cam surface 30, responsive to this left ward movement of the trailing rod 22 of the trailing mechanism. However, with the space available within the housing on the left hand, that is, the space 40, the trailing rod portion or section 22 is free to so move without moving the throw bar 12. Thus, the switch is thrown back to its opposite position without damage to the equipment. The switch will then remain in this position until the switch machine throw bar is thrown to the left position. Since the rail point is already in the left throw position, it bottoms on the stock rail. When the throw bar load exceeds the roller retention load, the trailing bar will be pulled out or extended and the ball means 24 will snap into the normal position, i.e., into detent or pocket 23.
By inspection, it is clear that the reverse mode of operation is possible. Likewise, it is clear that the position of the trailing device relative to the switch machine may be rotated 180°, if it is desired to install the switch machine on the opposite side of the tracks. As noted previously, another option for installation of the trailing mechanism is to mount such device as seen in FIGS. 1A and 1B, that is, between the stock rails as seen therein. In this mode, the trailing mechanism housing is mounted on the sync bar 15 between the switch points; the throw rod is extended out to attach to the throw bar of the switch machine as shown.
As noted previously, for the present type of installation of the invention of this trailing device, some lost motion must be incorporated in the system to make up for the difference between the switch throw that is required and the switch machine throw. As will be seen in FIG. 3, the ball slot detent or pocket 32 in the trailing device throw rod can be adjusted from a no lost motion position to 2.5 inches of lost motion. Such a configuration combines both the advantages of the trailing mechanism, as well as the lost motion function incorporated in the same device, which lost motion function is required for this type of switch installation.
Referring now to FIG. 3, there is shown a fragmentary view of a modified form of trailing mechanism which is essentially the same as the mechanism 16, shown in FIG. 2. However, herein the lost motion means 52 is incorporated within the trailing mechanism 16 already described. Instead of the ball means 24 being disposed in the limited pocket 23, as seen in FIG. 2, the ball means is disposed in a much extended pocket or pockets 32, such that only when the sloping cam surfaces 32A of the pockets 32 contact the ball means 24, is it forced against the retainer means 34 such that the trailing rod 22 can move as already described.
The invention having been thus described with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.
|
Apparatus for operating railroad switches, including operation in the trailing mode, and a switch machine having a throw bar and throw rod for enabling the throwing of switch points into selected positions so as to control the switching of rolling stock. A trailing device, including a trailing rod portion of the throw rod, is coupled to the throw bar, said device including an arrangement responsive to a wrong direction load impressed on said switch points so as to move said throw rod, for enabling non-damaging movement of said throw rod.
| 1
|
FIELD OF THE INVENTION
The present invention generally relates to physiological monitoring electrode systems, also known as electrocardiographs, and to components, including electrodes, for use in such systems.
BACKGROUND OF THE INVENTION
Considerable progress has been made in understanding how electrical signals are generated and used within the body. This progress has led to the ability to monitor various medical conditions by means of transferring electrical energy from the body of a patient. This transfer of electrical energy can be accomplished with electrode systems, which use electrodes to contact the skin of the patient and then transfer the electrical energy from the patient to a recording/monitoring device.
Examples of electrode systems include Computed Tomography imaging (“CT”) scans, cardioscopes, electrocardiographs, and electrocardiograms (“ECG”). Unless otherwise indicated, the term “ECG electrode system” will be used herein to represent all or any of these electrode-based devices. Such systems can be used for monitoring the operation of the heart, the respiratory system, and the arterial system.
Generally, a basic ECG electrode system includes the use of at least two electrodes and corresponding electrical lead wires. These lead wires transfer electrical energy from the electrodes, in position upon a patient, to a monitoring apparatus. The electrodes are typically small, round or square, electrically conductive patches, which can be attached to the patient's skin with an adhesive, or with suction, to make electrical contact with the patient's skin. Examples of such electrodes include the Holter Stress Monitoring adhesive electrode manufactured by Lead-Lok, Inc., and Chest Suction Electrodes manufactured by Medesign, Inc.
As is well known, chemical reactions within the body produce electrical current that can be monitored when the electrodes are placed on a patient's skin. Electrical signals generated by the patient's body are transferred from the patient through the electrodes to a monitoring apparatus via the lead wires. The monitoring apparatus then converts the electrical signals from the patient into graphic representations, which a clinician then interprets. Such monitoring apparatuses include the Microscan 2000 manufactured by Advanced Biosensor or the ELI 100/STM ST Monitor manufactured by Mortara.
Presently in the United States, a majority of the ECG electrode systems use some form of adhesive to adhere the electrode to the patient's skin. Examples of such systems include the ZIP TAB™ ECG monitoring electrodes manufactured by Taylor Industries, the Wet Gel/Clear Tape electrodes manufactured by Kendall, Inc, and the 1700 CLEARTRACE™ tape electrode manufactured by ConMed. While these adhesive ECG electrode systems can be useful in performing ECG monitoring, there are significant problems associated with them. First, such a system can result in considerable discomfort for the patient. Typically the area where the electrode is to be placed must first be shaven to ensure proper electrical connection. This process not only takes time, which adds to the expense of the overall procedure, but is also uncomfortable for the patient and increases the chance of injury and infection. Further, there are considerable costs associated with the use of these disposable electrodes, including the cost of the electrodes themselves, plus delivery costs, storage costs, and disposal costs.
Second, most adhesive ECG system electrodes are manufactured to be disposable, having some or most of their component parts in plastic form in order to permit the electrodes to be discarded after use, thereby resulting in additional waste and burden on the environment. Another drawback associated with conventional adhesive ECG systems is the loss of adhesiveness when the electrode is removed from the skin. For example, if a clinician needs to move an already adhered electrode in order to obtain a better patient signal, the chances of the electrode being effectively re-adhered to the patient are greatly reduced. This is because the electrode's ability to adhere is reduced each time the electrode is removed from the patient's skin. Yet another drawback is the risk that the patient might be allergic to the adhesive itself. Finally, there is the time consuming process of cleaning the adhesive off of the patient's skin after the ECG process is completed.
To address these problems, a handful of ECG electrode systems rely on suction, rather than adhesives, to attach the electrode to the patient's skin. The suction is created with a vacuum inside of the suction cups, which house the electrodes. In use, the electrodes can be effectively adhered to the patient's skin by placing the suction cup on the patient's skin. As the vacuum is created, the low pressure that results causes the patient's skin to rise up slightly toward, and into contact with, the electrode. Once attached in this fashion, the patient's electrical signals can travel from the electrode through a lead wire to a suitable monitoring station.
Early types of ECG suction electrode systems, such as that described in U.S. Pat. No. 2,580,628 and similarly manufactured by Medesign, Inc., employ an electrode in the form of small hemispheres made out of steel with a small rubber ball at the top end. Although quite simple in operation, such electrodes suffered from the inconsistent vacuum produced.
To resolve these drawbacks manufacturers began using pumps connected to the electrodes through air hoses to create the vacuum inside of the suction cup. Conventional pumps create the vacuum within an electrode by sucking air toward the pump, thereby creating negative pressure inside the suction cup. The negative pressure, in turn, pulls the cup toward the skin of the patient thus engaging the electrode with the skin. However, ECG electrode system must typically use low-suction vacuum pumps or reaction pumps, and thereby avoid the use of large suction, which could produce a high risk of a hematoma, leading to a variety of related problems. The use of low suction, however, increases the chance that electrodes will fall off in the course of use. This meant the ECG system operator would have to spend valuable time re-adhering the electrodes and this extra time produces extra labor costs.
In turn, ECG electrode systems such as those described in U.S. Pat. Nos. 3,640,270 and 4,556,065 began using more powerful pumps to reduce the amount of time it takes to secure the electrodes to the skin. However, such systems increased the risk that the vacuum might become too strong and thus increase the risk of hematomas. To prevent this from happening, the operator must manually adjust the pump to maintain the appropriate vacuum, in addition to also monitoring the ECG data itself.
Another disadvantage of the pump-based ECG systems, as described above, are the difficulties relating to the removal and re-adherence of the electrodes. For example, if an operator desires to move a single electrode after suction has been created, the operator must first turn off the pump; then wait for the suction to dissipate; move the electrode to its desired location; and finally reinitiate the suction process all over again. A further disadvantage, of both ECG pump systems described above, is that the air flowing towards the pump can carry contamination into the pump system, such as sweat, hair, and electrode paste. Although filters can be used, the risk of contamination of the system and infection of the patient is not entirely avoided. Further, the contamination of the pump system requires the system to be cleaned frequently and makes the cleanup of the system extremely difficult. The problems surrounding the cleanup of the system are also compounded by associated labor costs.
The above-described ECG electrode systems also tend to have drawbacks associated with their design. Because of their suction pump construction, the US Food and Drug Administration restricts the use of such systems in the United States due to the high possibility of cross-contamination. These systems are also limited due to their bulkiness. The fact that the systems must house pumps to generate the suction causes them to be quite heavy. Further, the acquisition modules or distribution boxes which route the signals to the recorders/monitors can be large and heavy due to the electronics on board which digitize the signals coming form the patient before being routed to the ECG recorder. This bulkiness causes the systems to be heavy and immobile and therefore reserved for use in one location. Finally, typical ECG system lead wires are 1/16 of an inch in diameter. These lead wires are expensive and reputed to break quite often due to their thin design and repeated movement throughout an ECG procedure.
What is clearly needed are ECG systems that provide an improved combination of various features, including physical characteristics (such as weight and compactness), cost, clinical efficacy, environmental protection, and patient comfort.
SUMMARY OF THE INVENTION
The present invention provides an improved ECG electrode system comprising:
(a) an air pump of suitable weight and compactness for providing positively pressurized air through an exit orifice,
(b) a flexible air connection hose of sufficient length to extend from the air pump to a patient and having first and second ends, the first end of the hose being operably and detachably connected, or connectable, to the exit orifice of the pump,
(c) an air distribution unit of sufficient weight and size and comprising a plurality of exit apertures and associated connectors, and at least one intake aperture and associated connector, the intake connector being detachably connected, or connectable, to the second end of the connection hose in order to controllably route pressurized air received from the pump, through the connection hose, and to the exit apertures,
(d) a plurality of electrode tubes each comprising first and second ends, the first ends of each being operably and detachably connected, or connectable, to a corresponding distribution unit exit aperture,
(e) a plurality of Venturi electrodes, each being operably and detachably connected, or connectable, to the second ends of the electrode tubes receiving compressed air from the electrode tubes, and
(f) a plurality of electrical leads adapted to sense and relay electrical charges occurring within the body by means of a centralized universal electrical connector, which is connectively compatible with an ECG recorder and/or monitor.
In a particularly preferred embodiment, the electrode leads are each positioned within respective air connections hoses, e.g., in a manner that is concentric or coaxial with the axis of the connection hoses, in order to both protect the leads themselves and facilitate their positioning.
The electrodes for use in a system of this invention are attached by means of a vacuum. The vacuum draws the patient's skin into contact with the electrode and holds it there with a constant force while the ECG recording is taken. The stream of air creating the vacuum is supplied to the each electrode housing by flexible tubing connected to a small DC-powered air pump. The ECG lead wires are preferably built into the air pressure tubing connected to each electrode. This cable assembly plugs into the connection box that, in turn, is connected to the ECG recorder and the air pressure pump. When the ECG exam is completed, the electrodes are released by turning off the air pressure pump. When airflow stops, the vacuum inside each electrode subsides and the electrodes fall off the patient within one second. This is in stark contrast to removing the adhesive electrodes, which can take anywhere from 10 to 180 seconds depending on the amount of electrodes and the patient being examined.
As compared with conventional “Welsh Cup” ECG electrodes, the air stream-powered vacuum of the present invention maintains constant, intimate contact between the electrode and the skin that is equal in quality or better than the contact that is possible with conductive creams, gels, and the adhesives used with disposable electrodes. The constant suction maintains a seal around surface irregularities, including hair. This allows optimal skin continuity to be maintained without shaving contact patches, where this would be customary and necessary practice with conventional electrodes.
No conductivity creams or gels are required with such electrodes, both because they are generally not needed, and because they can tend to clog the air jet passages. A water-based conductivity-enhancing fluid may optionally be used with such electrodes, where indicated. If an electrode needs to be repositioned, its suction can be neutralized temporarily by holding a finger over its air exit port. This causes the air stream to spill into the suction chamber, lifting the electrode off the skin. Eliminating time spent shaving, re-attaching slipped electrodes, and assisting patients with clean up after measurement significantly reduces the time needed to examine each patient. These timesavings, along with the elimination of expendable supplies used for connecting patients and reduction of lead wire replacement costs, contribute to notable savings for ECG operations.
In its preferred embodiment, a system according to the present invention provides an optimal combination of such features and functions, including those that arise: 1) in the manufacture, packaging, and transport of the system, 2) in the course of setting up and using the system, and/or 3) in related matters such as ongoing maintenance.
With respect to item 1) above, the system provides improved portability and ease of maintenance, due at least in part to its lightweight components and modular construction. The ECG electrode system of the present invention preferably has a pump unit, a charger unit, a distribution unit, a plurality of electrodes and a plurality of electrode tubes, a connection hose, a combination plug and recorder/monitor connector, and a jack box (e.g., connector hub) necessary when using digital ECG recorders/monitors.
The pump unit, in turn, preferably includes a pump, batteries, a control unit preferably having a plurality of charging indicators, a remote jack, an air aperture, and a charger jack. The pump unit is preferably comprised of a compact compressor pump. With a compact pump the ECG system of the present invention becomes lighter. This is because in some ECG suction systems the pump can be both heavy and large and thus the housing for the unit can be large. This can make the housing difficult to move from place to place.
Preferably, batteries are provided and used to supply power to the pump. It is preferred to have batteries that can provide a long electrical life. Preferably the batteries are of a sealed lead acid design, for its durability during repeated periods of charging and discharging. Further, the batteries preferably have a long electrical life and can typically withstand between 40 to 50 examinations before the batteries are in need of recharging.
The control unit is responsible for providing power from the batteries to the pump unit upon activation by the operator of the remote switch. Upon remote switch activation, the control unit preferably provides power to the pump and charging indicators. A printed circuit board has the necessary circuitry to receive inputs from the batteries, battery charger, and the remote switch. The printed circuit board circuitry then uses this information to determine whether the improved ECG system is on or off, whether the improved ECG system is charging or not, and what indicators should be lit to tell the operator how much charge is left.
The charger unit preferably has a charger plug and a wall plug. The charger unit is used to make the ECG system of the present invention more portable, for example, in order to perform an ECG on a patient in a location without a wall outlet or any other outside power source, such as a generator.
The distribution box preferably receives the electrode hose or hoses. The distribution box is made of a lightweight construction, preferably a durable plastic, to improve its portability. Unlike typical ECG systems, the distribution box will not typically have any electronics onboard which process the patient's electric signals. This helps ensure the boxes' compact construction. Further, the distribution box has a remote activation switch, which allows the operator to operate the improved ECG system several feet away from the pump unit.
With respect to item 2) above, and particularly in view of the electrodes and electrode tubes, the system provides an improved combination of features, such as ease of fixation to the body, tenacity, contamination prevention, and release characteristics, due at least in part to attachment based on the Venturi principle. Contamination prevention is improved, for instance, by having the air pushed away from the pump and towards the electrodes thus preventing any liquid, skin particles, hairs, dirt, etc. from being sucked into the system. The current system also provides improved control and reproducibility in the course of its use, e.g., permitting both constant and controllable air pressure. Such control can be achieved both by operator controls, e.g., pump controls, as well as by careful selection of nozzle diameters of the Venturi tubes themselves. Adhesion of the electrodes is both easier and quicker for the operator, and typically more effective and comfortable for the patient. Attachment can typically be achieved without the need to shave the body portion, and release of the electrodes can be quickly and easily accomplished by controlling (typically stopping) the flow of pressurized air in an appropriate manner.
Both the electrode tube and connection hoses have a strong outer sheath built from a flexible material such as rubber or polymeric material (e.g., polyvinylchloride (“PVC”)). This allows for ease of handling and allows for the tubes and hose to navigate around corners or obstacles. Preferably, the electrode tubes and connection hose are constructed so that all the lead wires traverse a lumen within the sheath. With this construction the electrical wires are kept out of the operator's way and therefore do not become a hazard to the operator, or become detached by accident. Further, the electrical wires are preferably of a thicker diameter, to reduce the possibility of breakage through repeated use.
Preferably the connection hose is detachably connected to a combination plug, e.g., in the form of a 15-pin mini-DSub connection. From here, an outside connection cable can be plugged into D-Sub connector at the combination plug and the other end plugged into any analog ECG recorder or monitor. The DSub connection allows for any analog recorder/monitor to be directly plugged in the ECG electrode system of the present invention. Further, a jack box can be connected to the DSub connector. The jack box is then connected and routes the various signals coming from the electrodes to several or one analog to digital converters, which then feed the digital signal to any digital ECG recorder or monitor. The jack box can also have the analog to digital converters onboard in which case the jack box then routes the digital signal to any digital ECG recorder or monitor. Further, the jack box can be connected to an acquisition box of a standard ECG system, which then digitizes the analog signal and then routes the signal to any digital ECG recorder or monitor.
With respect to item 3) above, the system provides low maintenance, and less waste, as compared to most conventional systems. For instance, as compared to conventional systems in which the electrodes, lead wires, electrode tubes, and the filter must be continually cleaned and maintained, in a system of the present invention typically only the electrodes themselves require periodic cleaning.
The present invention can also be used for performing ECG stress testing, for instance on ergometers and/or treadmills, as well as for “resting” ECGs. Typically, stress testing requires costly disposable adhesives based electrodes that are larger in size and have more conductive material fixed to their surface, as compared to smaller resting ECG electrodes. In a stress testing mode, the skin surfaces used for electrode placement are typically “shaved and sanded” with a razor and sandpaper (used to actually abrade the skin) in order to provide an improved conductive surface area for attachment of the adhesive electrode. Typically “skin prep” is required for the pre-cordial leads, V 1 & V 2 electrodes, in a process that can take any where from 4 to 15 minutes per electrode. Additionally, shaving of the skin exposes the patient to increased risk of infection from razors and or other microbes present in the examination field.
The present invention offers improved speed, safety, and patient comfort while delivering equivalent to improved performance, e.g., in terms of waveform accuracy, for the stress testing diagnostic procedure. The present invention endeavors to improved the speed of electrode application to the skin surface while simultaneously reducing preparation time. For optimal ECG accuracy, electrodes frequently need to be repositioned or moved. Using the Venturi based electrode of this invention, the stress testing operator can perform this maneuver in seconds, as compared to multiple minutes for a disposable adhesive electrode. Furthermore the Venturi electrode can be placed and fixed to the skin of even hairy individuals without the necessity of shaving, thus reducing the possibility of infection to the patient.
For use in such an embodiment, the system of this invention can include, for instance, a suitable vest for use as a secondary electrode stabilization component. Such a vest can be prepared using any suitable material in order to permit it to be both lightweight and comfortable, e.g., a mesh type material having over 90%, or even over 95% open space. One of the major benefits of a system of this type is the reduction of preparation time spent on the patient. Preparation time can be reduced from 10 to 15 minutes for adhesive-based disposable electrodes, only a few seconds for the Venturi based system. Also, as a patient sweats during a typical stress test, disposable adhesive based electrodes have been known to fall off and fail (due to sweat accumulation under the electrode). This problem is alleviated, if not avoided entirely, using the present system, because as skin surface moisture increases, electrical resistance decreases dramatically, and conductivity improves. Additionally, the Venturi based electrodes are non-disposable, which not only helps keep the environment cleaner but also delivers an improved cost-benefit ratio, which can contribute to lower overall healthcare costs. By comparison, adhesive-based disposable electrodes can cost anywhere from $1.25 to $3.50 (a stress test requires a minimum of 10 electrodes) depending on the volume of total tests performed the medical practitioner.
BRIEF DESCRIPTION OF THE DRAWINGS
In the Figures:
FIG. 1 is a front perspective view of an embodiment of an ECG system of the present invention;
FIG. 2 is an exploded view showing the respective component parts of a system according to FIG. 1 ;
FIG. 3 is a front view of the pump unit opened to show an embodiment of the pump unit of the present invention;
FIG. 4 is a front view of the charger unit opened to show an embodiment of the battery charger of FIG. 1 ;
FIG. 5 is a cross sectional view of a preferred embodiment of the electrode tubes and connection hose;
FIG. 6 is a cross sectional front view of a preferred embodiment of a suction electrode suitable for use in a system of this invention;
FIG. 7 is a cross sectional profile view of a preferred embodiment of the suction electrode of FIG. 6 ;
FIG. 8 is a bottom view of the suction electrode of FIG. 6 ;
FIG. 9 is a cut away profile view of a Venturi tube in a preferred embodiment of the present invention;
FIG. 10 is a schematic view of the electrical and pneumatic distribution in a preferred embodiment of the present invention;
FIG. 11 is a front perspective view of the connection between the DSub connector and the jack box; and
FIG. 12 is a front perspective view of the connection between the jack box of FIG. 11 and a typical acquisition module.
DESCRIPTION OF THE PREFERRED EMBODIMENT
To assist in an understanding of the invention, a preferred embodiment or embodiments will now be described in detail. Reference will be frequently taken to the Figures, which are summarized above. Reference numerals will be used to indicate certain parts and locations in the Figures. The same reference numerals will be used to indicate the same parts or locations throughout the Figures unless otherwise indicated.
With respect to FIGS. 1 and 2 , an improved ECG electrode system 10 is shown having a pump unit 12 , a charger unit 14 , a distribution unit 16 , a plurality of electrodes 18 , a plurality of electrode tubes 20 , a connection hose 22 , a combination plug 24 and recorder/monitor connector 25 , and a jack box 94 , discussed in more detail herein. The following discussion will describe each part in detail, including how the individual parts interact during operation.
With respect to FIGS. 2 and 3 , an improved pump unit 12 is shown having a pump 26 , batteries 29 , a control unit 28 having a plurality of charging indicators 30 , a remote jack 32 , an air aperture 34 , and a charger jack 36 .
Pump 26 can be any suitable air compressor, such as an oil-less reciprocating compressor, a gas compressor, or reciprocating compressor designed to supply a vacuum of approximately 150 to 200 mbars, although the optimum operating condition is an electrode vacuum of between 120 and 180 mbars to lessen the risk of hematoma. Pump 26 is preferably a compact Thomas compressor pump, model number 315CDC40/24, manufactured by Thomas Compressors and Vacuum Pumps, Sheboygan, WI 53802. With a compact pump, ECG system 10 becomes lighter. With further reference to FIG. 3 , pump 26 is connected to control unit 28 with air hose 38 and supplies compressed air from pump 26 to air connector 34 when system 10 is operating.
Batteries 29 can be any suitable batteries such as alkaline batteries, nickel-cadmium, or lithium batteries, which can supply approximately 12–25VDC. Batteries 29 are preferably comprised of (3) 6V/12 Ah batteries made of a sealed lead acid design, and provide suitable internal voltage (e.g., 12–18 VDC) to ECG electrode system 10 ; though other batteries are contemplated for use as well, without straying from the sprit of the invention. However, it is preferred to have batteries that can provide a long electrical life. The sealed lead acid design is chosen for its durability during repeated periods of charging and discharging. Batteries 29 provide power to pump unit 12 and in particular to pump 26 and control unit 28 . Further, batteries 29 have a long electrical life and can typically withstand between 40–50 examinations before the batteries are in need of recharging.
Control unit 28 preferably includes a printed circuit board which houses the appropriate circuitry, such as memory and a microprocessor or microcontroller or specially manufactured integrated circuit, which allows for various inputs and outputs. Control unit 28 is responsible for providing power from batteries 29 to pump unit 12 upon activation by the operator of remote switch 70 , discussed below. Upon remote switch activation, control unit 28 provides power to pump 26 and charging indicators 30 . The printed circuit board is responsible for providing power to the proper indicators 30 during charging and use. The printed circuit board receives inputs from batteries 29 , battery charger 14 , and remote switch 70 . The printed circuit board then determines whether system 10 is on or off, whether system 10 is charging or not, and what indicators 30 should be lit to tell the operator how much charge is left.
With respect to FIGS. 2 and 4 , charger unit 14 is shown having a charger plug 40 , and a wall plug 42 . Charger unit 14 can be any suitable charging unit. For example, the battery charger can be any unit that converts 115V, 60 Hz, and 30 VA to appropriate charging voltage (e.g., about 12VDC to about 22VDC). The embodiment in FIGS. 3 and 4 specifically shows a charger unit which connects to a standard wall outlet, however, it is contemplated that charger unit 14 can utilize any power source for charging purposes other than a standard wall outlet. It is further contemplated that pump unit 12 can plug directly into a standard wall outlet.
However, in a preferred embodiment system 10 uses batteries 29 and battery charger 14 in order to make the unit more portable. Preferably, before the system's initial use, batteries 29 are charged for approximately 6 hours to ensure a proper charge. However, after the initial charge, the charging time is considerably reduced to approximately 2 hours. Therefore, the amount of downtime for the unit is decreased and it can quickly be used again.
As shown, the printed circuit board will sound a 10 second audible sound, such as a beep, and the <25% indicator lamp will activate each time batteries 29 is in need of a recharge. The audible sound and indicator lamp will also activate each time the unit is turned on and system 10 requires charging. However, system 10 can perform more ECGs in this condition, but the reliability of the electrode suction, and thus the accuracy of the ECG data, will be reduced with every examination after the initial indication of a need for charging.
With reference to FIG. 2 , distribution box 16 can be any suitable distribution box or acquisition module commonly used in ECG electrode systems. Distribution box 16 preferably has 10 apertures 66 which can receive corresponding electrode hose or hoses 20 . Distribution box 16 is made of a lightweight construction, preferably a durable plastic, to make it portable. Unlike typical ECG systems, box 16 does not have any electronics onboard which convert the patient's electric signals from analog to digital. Distribution box 16 has a remote activation switch 70 . When the operator activates system 10 from remote switch 70 an electrical signal is sent down connection wires 68 located inside connection hose 22 into pump unit 12 to control unit 28 ( FIG. 5 ). Control unit 28 then relays power from batteries 29 to pump 26 , which begins operating and pumping air throughout system 10 . The fact that no electronics are typically required to be on board not only results in light weight and compactness, but also in nearly universal utility with all recorders. All recorders have to deal with 1 mV analog signals at the very front end, and it is at that position where the present device can be inserted into the signal path.
With respect to FIG. 5 , improved electrode tube 20 and connection hose 22 can be any suitable hose or tubes used for the delivery of air pressure. Both tube 20 and hose 22 preferably are constructed to withstand air pressures up to about 500-lbs/square foot. Further, both tube and hose 22 preferably have a strong outer sheath 23 built from a flexible material such as rubber or poly(vinylchloride) (PVC). This allows for ease of handling of tube 20 and hose 22 and allows for the hose to navigate around corners or obstacles. Preferably, tube 20 and hose 22 are constructed so that all lead wires traverse inside of sheath 23 .
Due to the long flexible connection hose 22 connecting pump unit 12 and distribution box 16 , system 10 can be installed on a cart, such as the mobile 20TX treatment cart distributed by Total Pharmacy Supply, Inc. in Arlington, Tex. Thus, pump unit 12 can be placed anywhere on the cart, for example, on the lower shelf of the cart. The flexibility of connection hose 22 allows for distribution box 16 to be placed onto or beside the patient during the examination. This eliminates several electrode hoses from becoming tripping hazards or from becoming disconnected from the patient because the electrode hoses are now local to the patient. Therefore the risk of injury or disconnection is significantly reduced.
As stated above, sheath 23 is preferably made of a flexible material such as a soft PVC or rubber. Hoses 20 and 22 preferably provide an inner diameter that leaves an opening 80 large enough for the proper amount of pressurized air to reach distribution unit 16 and electrode 18 . Further, traversing the inside diameter of hoses 20 and 22 are lead wires 64 and connection wires 68 . Wires 64 and 68 can be of any type of electrical construction, however, in a preferred embodiment wires 64 and 68 are constructed with a conductor 82 preferably made out of copper with a central conductor made from stainless steel. Surrounding conductor 82 is a layer of Polytetrafluoroethylene (“PTFE”) or other suitable insulation 84 . Outside of PTFE layer 84 is a thin layer of silver plated copper shielding 86 . Shielding 86 prevents any outside electronic disturbance from penetrating and corrupting any data traversing along conductor 84 . Finally, another outer PTFE insulation layer 88 covers shielding layer 86 to protect shielding layer 86 .
Electrode 18 can be any suitable Venturi type electrode that generally has a cup-shaped housing of non-metallic material. The cup-shaped housing preferably has a mouth bounded by a tissue-engaging rim. The housing contains an electrode, which is recessed within the rim but accessible by way of its mouth in order to make contact with the skin of the patient. The electrode preferably is plated with a mixture of silver and one or more silver salts such as silver chloride, silver bromide, silver rhodamine, or silver cyanide but can be plated with any electrically conductive metal.
Now with respect to FIGS. 6 , 7 , and 8 , a preferred embodiment of electrode 18 is shown. Electrode 18 includes a cup-shaped housing 41 of a one-piece rubbery material. Preferably the material is flexible, such as silicon, and is able to make a good seal when in contact with the patient's skin. Housing 41 includes an end-wall 54 connected across an annular sidewall 55 . Sidewall 55 has a free terminal edge defining a rim 42 , which defines or bounds an open mouth 43 into a main recess 56 of housing 41 . During operation a low-pressure vacuum created by pump 26 causes organic tissue to be sucked through mouth 43 and enter recess 56 and then engage contact plate 44 of electrode 18 , see FIG. 6 .
Rim 42 provides for engaging tissue and creating a seal there against when the pressure vacuum is created. As stated above, the sealing is easily accomplished if the housing material is rubbery or flexible in nature. Within housing 41 is a central material extension 59 depending from the underside of end-wall 54 . Extension 59 defines a leg well 60 exposing therein a portion of the Venturi tube 48 for the legs of contact plate 44 to snap onto or damp about, as can be ascertained from FIG. 6 . The rubbery housing material defining the leg well 60 is sized to engage electrode legs 45 on multiple sides thereof and to thereby aid in holding contact plate 44 securely in place. Housing 41 includes a transverse through passage 61 in which Venturi tube 48 resides. Generally passage 61 is smaller in diameter than the exterior of Venturi tube 48 and thereby the material defining the passage 61 grips and frictionally holds Venturi tube 48 securely in place after it has been placed into passage 61 . Further, the tight fitting rubbery material of housing 41 also seals in the appropriate areas against Venturi tube 48 .
Through passage 61 is defined or bounded by the rubbery material of housing 41 , and includes an opening 50 to through passage 61 aligned with suction port 46 of Venturi tube 48 . Therefore, a vacuum can be created in main recess 56 of housing 41 . An output port 47 to through passage 61 is aligned with the gas output end of Venturi tube 48 , which allows the pressurized gas distributed from pump 26 , to exhaust to the exterior of housing 41 . Thus, all contaminates are pushed out of ECG electrode system 10 . Through passage 61 further includes an opening 62 for the introduction of pressurized gas into Venturi tube 48 at threaded end 49 . Threaded end 49 of Venturi tube 48 is exposed for connection to electrode hose 20 and an output lead wire 64 . In a preferred embodiment, contact plate 44 is positioned in housing 41 and at least in part exposed in recess 56 through mouth 43 .
Electrode 18 comprises contact plate 44 with a first side facing housing mouth 43 and providing a surface for engaging organic tissue. The first side of contact plate 44 is shown circular in FIG. 8 , and is generally flat and smooth so as to not be abrasive to skin. For further comfort against the skin (tissue) the lower corner is a rounded-over or beveled (see FIG. 6 ) so to be smooth against the skin. An opposite and a second side of electrode contact plate 44 includes a pair of extensions or legs 45 and a limiter post 52 centered between legs 45 . Legs 45 and limiter post 52 point away from the backside of contact plate 44 and are comprised of plastic. The plastics from which contact plate 44 are molded can be acrylonitrile-butadiene-styrene (“ABS”), although other plastics can be utilized. Contact plate 44 is an inexpensive one-piece molded plastic base or substrate, which is, coated with a thin and thus inexpensive exterior layer of silver/silver chloride AgAgCl so as to be electrically conductive on the exterior surface of contact plate 44 . Silver/silver chloride in a thickness of 0.004 inches functions well, but the thickness can be varied widely within the scope of the invention. A coating of low resistance electrically conductive material such as a silver based material other than silver/silver chloride or equivalent can be used on the exterior of the electrode within the scope of the invention although the silver/silver chloride proves more durable.
The legs 45 of electrode 18 are resilient because of the strength of the plastic and shape thereof, and are spaced apart from one another to receive Venturi tube 48 in-between and snap fit or clamp there against to physically and electrically connect with Venturi tube 48 . The normal or non-loaded spacing between legs 45 in the area where tube 48 is clamped is less than the diameter or width of the Venturi tube 48 so that the legs 45 are continuously trying to move inward when tube 48 is clamped, thereby clamping pressure and thus good contact is maintained between legs 45 and Venturi tube 48 . Each leg 45 includes, what is in effect, a curved indentation 51 in which Venturi tube 48 resides. Indention 51 as shown in FIG. 6 , is defined by the leg end curving inward to form a hook or prong like structure overhanging the top of tube 48 , and thereby increases the stability of the connection as well as increasing the surface area contact between legs 45 and Venturi tube 48 for lower electrical resistance at the contact points.
Limit or limiter post 52 extends up to contact the underside of Venturi tube 48 and aid in supporting tube 48 and legs 45 properly positioned to one another. The terminal end of center material extension 59 of housing 41 abuts the backside of contact plate 44 and thereby provides further position stabilizing relative to Venturi tube 48 . Legs 45 fit snugly into leg well 60 and therefore the rounded outer corners as shown in FIG. 6 prevent hanging-up or snagging when electrode 18 is pushed into well 60 to engage Venturi tube 48 . Venturi tube 48 is preferably an elongated tube of brass, copper or steel, which is electrically conductive at least on the exterior surface thereof, and preferably is gold plated so corrosion will not occur and the high or higher electrical conductivity provided by the plating over the base or substrate material (brass) will remain over a long period of time.
With reference to FIG. 9 , Venturi tube 48 has an internal Venturi arrangement with a suction port 66 positioned such that when fast moving or high-pressure gas (e.g., air) is passed through Venturi tube 48 , a low-pressure constant vacuum is created in recess 56 of housing 41 . It is the uniformity of each suction port 66 in each Venturi tube 48 , which allows the clinician to disregard the pump during the ECG process. Such a vacuum in recess 56 is capable of allowing tissue to engage rim 42 , bring the tissue into contact with electrode plate 44 to establish electrically conductive contact with the tissue. The vacuum also holds contactor 44 stationary against the tissue regardless of orientation, i.e., vertical, up-side-down, with this good holding power aided by the fact contactor 44 is light in weight. Venturi tube 48 is electrically conductive from electrode legs 45 to threaded end 49 of the tube 48 . The threaded end 49 is exposed for connection to electrode hose 20 , which also includes an output lead wire 64 . The lead wire 64 is connected to a conductive threaded end of electrode hose 20 , which connects at end 49 to the Venturi tube 48 .
Therefore the patient's tissue is electrically connected through electrode plate 44 to electrode legs 45 to Venturi tube 48 to threaded end 49 , to the lead wire 64 in electrode hose 20 . Venturi tube 48 fits tightly into passage 61 of housing 41 , and includes one or more collars 63 shown in FIG. 7 to aid in stabilizing the tube relative to the housing.
With reference to FIG. 10 , an electrical and pneumatic diagram is shown of a preferred embodiment of the present invention. From the Figure it can be shown that each electrode hose 20 has a lead wire 64 that travels inside the length of electrode hose 20 . However, lead wire 64 is small relative to hose 20 and therefore allows enough room for pressurized air to travel to electrode 18 . With reference to FIG. 2 , the opposite end of electrode hose 20 is detachably connected to one of a plurality of apertures 66 located on distribution box 16 . With reference once again to FIG. 10 , when electrode hose 20 is plugged into aperture 66 , lead wire 64 is electrically connected to connection wires 68 , which travel down the center of connection hose 22 . When connection hose 22 is detachably connected to combination plug 24 recorder connectors 68 are electrically connected to 15-pin mini-DSub connection 25 . From here an outside connection cable can be plugged into D-Sub connector 25 at combination plug 24 and the other end plugged into any ECG recorder or monitor. DSub connection 25 allows for any recorder/monitor to be plugged in ECG electrode system 10 .
Similar to lead wires 64 , connection wires 68 are small relative to the size of connection hose 22 and therefore pressurized air can pass from pump unit 12 to distribution box 16 . Further, with respect to FIG. 2 , the pneumatic connection between pump 26 , combination plug 24 , and distribution box 16 can be seen. Pump 26 supplies pressurized air through air hose 38 , then through air aperture 34 , to combination plug 24 , which will route pressurized air through to connection hose 22 , which will then route pressurized air to distribution box 16 , which routes the air to electrode hose 20 , which then routes the pressurized air to electrode 18 , which then expels the pressurized air through output port 47 .
With reference to FIG. 11 , DSub connection 25 allows for any analog recorder/monitor to be directly connected to ECG electrode system 10 of the present invention. Because the signal from electrodes 18 is never digitized, the signal can be sent directly to an analog recorder/monitor where the signal can be displayed. In addition, jack box 94 can be connected to D-Sub connector 25 via cable connector 92 and route the various signals coming from electrodes 18 to several or one analog to digital converters. The analog to digital converters can then feed the digital signals that result to any digital ECG recorder or monitor. Thus system 10 is adaptable to be used with any analog or digital recorder/monitor. It is further contemplated that jack box 94 could also have the analog to digital converters onboard, in which case the jack box would then route the digital signal to any digital ECG recorder/monitor. In a preferred embodiment, jack box 94 is connected to an acquisition module 96 ( FIG. 12 ) of an ECG system, which can then digitize the analog signal and route the signal to any digital ECG recorder or monitor.
With further reference to FIG. 11 , jack box 94 has 10 electrical input connections 98 and a ground connection 100 which are utilized to connect with any acquisition box 96 associated with an ECG system. Acquisition box 96 is implemented with ECG systems, which digitize the signals from the electrodes before routing these signals to an ECG recorder/monitor. With reference to FIG. 12 , a schematic detailing the process of interconnecting jack box 94 to an acquisition box 96 of a standard ECG system is shown. The signals picked up by electrodes 18 and routed through to DSub connector 25 , as discussed in detail above, are then routed through electrical connector 92 , compatible with DSub connector 25 , to jack box 94 . Jack box 94 is then connected to acquisition box 96 via acquisition module conductors 102 which are plugged into jack box 94 via banana clips. Acquisition module 96 then digitizes the signal and routes the signal to a digital ECG recorder or monitor via electrical connection 104 .
To activate ECG electrode system 10 the operator depresses remote activation switch 70 located at distribution box 16 . As stated above, when control unit 28 receives the activation signal the microprocessor then initiates power from batteries 29 to pump 26 . Pump 26 then relays compressed air through connection hose 22 to distribution unit 16 which directs the compressed air through electrode tubes 20 to the electrode to create a suction.
The operator then sprays an electrolytic solution of ionized water about six inches away from a location on a patient where the operator desires to place electrode 18 . The operator should make sure that output port 47 remains unblocked, because this would stop the flow of air through electrode 18 and thus no vacuum would be created. The system typically avoids the need to shave the body portion, and instead the operator can typically apply an increased amount of solution and then press down electrode 18 while moving it in a circular motion. Then by lifting their finger on and off the output port 47 the operator can verify that electrode 18 is securely fixed to the patient. If the patient has large breasts, for instance, the operator would simply rotate electrode 18 45° to 90° from vertical so that output port 47 is not covered by the resting breast. The operator would have to remember that loose tissue would close output port 47 and cause limited or no suction to the patient. Because of the uniform suction created by pump 26 , all electrodes 18 attach very quickly. Typically an operator could attach all ten electrodes 18 in less than 15 seconds.
Therefore, the operator does not have to shave the patient and thus the risk of infection is lowered and patient comfort is increased. Further, because of the quick adhesion of electrodes 18 the operator is able to begin and finish the ECG monitoring in a matter of minutes, therefore, labor cost is reduced. Finally, because an ionized water solution is used, clean up can be completed with a quick swipe of a paper towel and in some situations the ionized water simply evaporates and if the patient is sweaty then no ionized water needs to be applied because of the salt in the sweat is a good electrical conductor.
After the examination is completed the operator simply switches off ECG electrode system 10 by pressing remote switch 70 at distribution box 16 . All electrodes 18 will then detach instantly. The operator then stows electrodes 18 and electrode hoses 20 in a safe and dry place to prevent contamination. The operator should avoid any contact between electrode contact plates 44 and metallic materials to reduce the possibility of chipping the silver/silver-chloride coating on contact plate 44 and reducing the electric conductivity of plate 44 .
As discussed above, depending on the duration of each examination typically after 40 – 50 examinations batteries 29 will start to loose its charge. When this occurs control unit 28 will use indicator lights 30 and an audible alarm will sound to inform the clinician that use of battery charger 14 is necessary. Indicator lights 30 are visible at all times and reflect the current level of power available. Indicator lights 30 are divided into 6 groups:
Currently charging
CHARGE
Full charge
100%
3/4 charge
75%
1/2 charge
50
1/4 charge
25
Below 1/4 charge
<25
(Batteries Low)
In addition a 10 second audible beep will sound and the<25% light will activate each time the unit is turned on. This indicates that the batteries 29 need to be recharged. It is of note, that more ECGs can be performed in this state; however, the reliability of the electrode suction will be reduced with every examination beyond this point. Therefore, when batteries 29 do need charging the user simply has to plug charger plug 40 into charger jack 36 and then plug main plug 42 into a wall outlet. It is of note that system 10 can not operate during the battery charging operation in order to prevent any possible harm to the patient or any faulty readings by system 10 .
After an examination is completed the clinician need simply switch off system 10 by pressing remote switch 70 at distribution box 16 . All electrodes 18 will detach immediately after loss of airflow.
The Venturi principle makes cleaning ECG electrode system 10 very easy. The operator simply switches on the system 10 by remote switch 70 and then hangs electrodes 18 in a vessel of water completely immersed. The operator then allows electrodes 18 to rest in the water for one to two minutes. When the operator removes electrodes 18 from the water the operator should let system 10 run for three minutes to allow electrodes 18 to air dry. This leaves the operator time to attend to other duties while drying occurs.
It will be appreciated that the present invention can take many forms and embodiments. The true essence and spirit of this invention are defined in the appended claims, and it is not intended that the embodiment of the invention presented herein should limit the scope thereof.
|
The present invention provides for an ECG electrode system that includes the use of electrodes adapted to attach to the body via suction. The invention includes a lightweight and compact air pump in combination with air connection hoses, a lightweight air distribution unit, associated electrode tubes, and respective electrodes adapted to be positioned by the Venturi principle, and corresponding electrical leads and recorders/monitors. The electrode leads can each be positioned within respective air connections hoses, e.g., in a manner that is concentric or coaxial with the axis of the connection hoses, in order to both protect the leads themselves and facilitate their positioning.
| 0
|
BACKGROUND
1. Field of the Invention
This invention relates generally to pressurized fluid devices and, more particularly, to improved structure for introducing pressurized fluid into such devices in a simplified, rapid and reliable manner.
2. The Prior Art
In a device known from German Offenlegungsschrift No. 19 25 963 (see U.S. Pat. No. Re. 28,329), the piston rod is provided with a section of reduced diameter, which section is adapted to be brought into radial alignment with a sealing member fixedly mounted to the container, or cylinder, at the point where the piston rod enters the container, so that the pressurized fluid can pass through a gap between the piston rod and the piston rod passage and across the sealing member. After filling, however, care must be taken that the reduced diameter section of the piston rod does not again come into radial alignment with the sealing member, because in such case the pressurized fluid could escape. Further, the section of reduced diameter must be very carefully machined in order to prevent damage to the sealing member, since the sealing member must prevent leakage of the pressurized fluid during normal operation of the device.
It is further known from German Gebrauchsmuster No. 74 22 901 to fill the container cavity through a gap between the piston rod passage and the piston rod across a lip-shaped sealing member fixed at the piston rod passage, the lip-shaped sealing member acting as a check valve, which opens under the action of an outer filling pressure and sealingly engages the piston rod under the action of the pressure of the fluid within the cavity. Such lip-shaped sealing members must be manufactured very precisely and have a complicated shape, so that their manufacture is expensive. Such lip-shaped sealing members, moreover, must be supported by a supporting member, which must also be shaped very precisely.
SUMMARY
It is an object of the present invention to provide a pressurized fluid device of the type referred to in which the fluid-filling passage is closed by a closure member of simple and inexpensive design. It is further desirable that the closure member be easily maintainable in a filling position before and during the filling operation and also easily be brought into a sealing position with respect to the filling passage after termination of the filling.
In furtherance of these objects, the closure member of the invention is mounted within the container cavity so as to be movable to a filling position remote from the sealing position during filling of the cavity with pressurized fluid and means are provided on the closure member and on the piston rod for moving the closure member towards the sealing position by movement of the piston rod with respect to said container means.
According to a preferred embodiment of the invention, the fluid filling passage is defined by a gap between the piston rod passage and the piston rod, and the closure member is defined by an annular closure member engaging the piston rod and the container at the inner end of the gap during operation of the device. The annular closure member may, in this preferred embodiment of the invention, remain in constant frictional engagement with the face of the piston rod, both in the filling position and in the sealing position, so that no deformation of the closure member in its most sensitive sealing surface, i.e., the surface adjacent and surrounding the piston rod, is necessary during the filling operation. Those parts of the annular closure member that are influenced by the movement of the annular sealing member between the filling position and the sealing position are less sensitive to damage, because they have to fulfill only a static sealing function and not a dynamic sealing function, a dynamic sealing function occurring only between the annular closure member and the piston rod during operation.
If desired, the closure member of the invention may be moved fully to the sealing position by movement of the piston rod. Alternatively, however, the closure member could be moved by the piston rod, after filling, merely to an intermediate position in which the closure member separates a first compartment of the cavity, containing pressurized fluid, from a second compartment of the cavity, which is in communication with the surrounding atmosphere by the filling passage. Once the closure member has been moved to the intermediate position by the piston rod, the closure member will be urged towards the sealing position by the pressure within the first compartment of the container, while expelling the fluid within the second compartment through the filling passage.
According to other advantageous features of the invention, the container wall may be deformed inwardly in the region of the sealing position of the closure member so as to cooperate within and enhance the sealing effectiveness of the closure member. Alternatively, the container wall could be deformed outwardly to define the gas-filling position of the closure member. Again, a separate, resilient member could be provided internally of the container as an aid in sealing the container cavity when the closure member is in the sealing position.
The pressurized fluid device of the invention is useful, for example, as a gas spring or as a hydraulic or pneumatic shock absorber. Further fields of use of the invention will be apparent to those skilled in the art. The pressure of the pressurized fluid may be very high, as e.g. 10 to 100 bar.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and advantages of the invention will be apparent from the following description of exemplary embodiments thereof, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a partial longitudinal sectional view of a first embodiment of the invention, showing the parts as they would appear during filling of the cylinder;
FIG. 2 is a partial longitudinal sectional view of the embodiment of FIG. 1, showing the parts as they would appear during normal operation of the device;
FIG. 3 is a partial longitudinal sectional view, similar to that of FIG. 1, of a second embodiment of the invention, but showing the parts in the cylinder-filling position;
FIG. 4 is a partial longitudinal sectional view of a third embodiment of the invention, showing the parts in the filling position;
FIG. 5 shows the embodiment of FIG. 4 after filling and ready for normal operation;
FIG. 6 is a partial longitudinal sectional view of a fourth embodiment of the invention, also showing the parts in the filling position;
FIG. 7 shows the embodiment of FIG. 6 after filling and ready for operation; and
FIG. 8 is a partial longitudinal view of a fifth embodiment of the invention.
DETAILED DESCRIPTION
In FIG. 1, there is shown a gas spring comprising a cylinder member 1. This cylinder member 1 is closed at one end thereof by an end wall 30 and at the other end thereof by an annular plug member 5. The annular plug member 5 is sealingly mounted within the upper end of the cylinder member 1 by inward rolling of the upper end 32 of the cylinder member 1. A piston rod passage 33 is defined by the annular plug member 5. A piston rod 2 is introduced into a cavity 17 within the cylinder member 1 through the piston rod passage 33, and an annular gap 34 is defined between the outer cylindrical face of the piston rod 2 and the inner cylindrical face of the piston rod passage 33. This annular gap may be extremely narrow, e.g., just as wide as to permit an introduction of pressurized fluid through the gap 34, so that the guiding function of the piston rod passage 33 for the piston rod 2 is not degraded.
At the inner end of the piston rod 2 within the cavity 17 there is provided a piston unit of conventional design which separates the cavity into a working chamber 17a surrounding the piston rod 2 and a working chamber 17b adjacent the end wall 30. This piston unit 3 comprises a piston member 3a, a disc member 3b and a piston ring 3c axially movable between the piston member 3a and the disc member 3b. A flow passage 17d interconnects the working chambers 17a and 17b. The cross sectional area of the flow passage 17d is changed in response to the direction of movement of the piston rod 2 due to the movability of the piston ring 3c between the piston member 3a and the disc member 3b. During outward movement of the piston rod 2 the piston ring 3c is in the position as shown in FIG. 1, in which an annular gap 3e between the piston member 3a and the inner cylindrical face 1a of the cylinder member is closed by the piston ring 3c, so that the flow section through the piston unit 3 is at a minimum. Hence outward movement of the piston rod 2 under the action of pressurized fluid contained within the cavity 17 is damped.
An annular closure member 6 of elastomeric material surrounds the piston rod 2 and frictionally engages the outer cylindrical face of the piston rod 2 in a fluid tight manner. In FIG. 1, the annular closure member 6 is shown in the fluid-filling position. As shown in FIG. 1, the outer diameter of the annular closure member 6 is smaller than the inner diameter of the cylinder wall 1, so that a gap 14 is defined between the annular closure member 6 and the inner cylindrical face 1a of the cylinder wall 1.
In FIG. 1, a fluid-filling head 35 is shown applied to the upper end of the cylinder member 2. The filling head 35 is applied by a sealing ring 36 to the rounded upper edge 38 of the cylinder member 1. A filling chamber 39 is defined within the filling head 35. The filling head 35 is sealed relative to the piston rod 2 by a seal member 40. The filling chamber 39 is connectable to a pressurized fluid source 41 by a filling valve 42 and a filling channel 43. When a pressurized fluid is supplied to the filling chamber 39 the pressurized fluid can enter into the cavity 17 through the annular gap 34. It can pass also around the annular closure member 6 and through the piston unit 3, so that both working chambers 17a and 17b are filled. As will be readily understood, the filling head 35 may be constructed fully to enclose the outer section of the piston rod 2, in which case no sealing member would be necessary.
When the cavity 17 is filled, i.e. when the desired pressure has been achieved, the piston rod 2 is moved upwards as seen in FIG. 1, so that the annular closure member 6 is brought into contact with an inwardly directed terminal face 44 of the annular plug member 5. The inner end 34a of the annular gap 34 is thereby closed by the annular closure member 6, which sealingly engages both the outer cylindrical face of the piston rod 2 and the inwardly directed terminal face 44 of the annular plug member 5. The annular closure member 6 is pressed by the pressure within the cavity 17a against both the outer cylindrical face of the piston rod 2 and the terminal face 44, when the pressure within the filling chamber 39 is removed.
As shown in FIG. 1, the cylinder member is provided with an axial section 45 of reduced inner diameter. The transition between the axial section 45 and the cylindrical main section of the cylinder member 1 is defined by a frusto-conical section 46. This frusto-conical section 46 defines a shoulder face 47. A second frusto-conical terminal section 48 is provided between the axial section 45 and the annular plug member 5. The outer diameter of the annular closure member 6 is equal to or preferably somewhat larger than the inner diameter of the axial section 45.
When the fluid-filling step has been completed, the piston rod 2 is moved upward until the annular closure member 6 engages the shoulder face 47. This upward movement of the annular closure member 6 is achieved by the frictional engagement of the annular closure member 6 and the piston rod 2. If this frictional engagement is not sufficient for moving the annular closure member 6 upwards, the annular closure member 6 will be moved upwards upon engagement with an abutment face 49 of the disc member 3b.
As illustrated in FIG. 1, the annular closure member 6 cannot be brought into direct contact with the terminal face 44 simply by the movement of the piston rod 2, because the disc member 3b engages the shoulder face 47 before the annular closure member arrives at the terminal face 44. When, however, the annular closure member 6 has been brought into sealing engagement with the shoulder face 47 or with the internal face of the axial section 45, no further movement of the annular closure member by the piston rod is necessary. As soon as the annular closure member 6 has arrived in the intermediate position, as shown in dotted lines in FIG. 1, the fluid pressure in the cavity 17 presses the annular closure member 6 upwards after the pressure within filling chamber 39 has been removed. This is due to the fact that the pressurized fluid within compartment 50 can escape through the filling gap 34, whereas the pressurized fluid contained within the compartment 51 below the annular closure member 6 acts on the annular closure member 6. So the annular closure member 6 is moved upwards by the pressurized fluid in the compartment 51 through the axial section 45 and into the terminal section 48. When in the terminal section 48 the annular closure member 6 is in sealing engagement with the terminal face 44. If the outer diameter of the annular closure member 6 is greater than the inner diameter of the axial section 45, the annular closure member 6 is retained in its sealing position by mechanical engagement with the inner face of the terminal section 48. But even if the outer diameter of the annular closure member 6 is equal to the inner diameter of the axial section 45 the annular closure member 6 is maintained in its sealing position by the internal pressure within the cavity 17.
It is evident, therefore, that during the filling action no deformation of the surface area of the annular closure member 6 which is in contact with the outer cylindrical face of the piston rod 2, which surface area fulfills a dynamic sealing action when, in normal operation, the piston rod 2 is axially moved with respect to the cylinder member 1, is necessary.
In FIG. 2, the annular closure member 6 is shown in the sealing position. So positioned, the annular sealing member 6 is still in engagement with the axial section 45 of reduced diameter, so that the annular closure member also assists the sealing action between the annular plug member 5 and the cylinder member 1.
In the embodiment of FIG. 3 analogous parts are designated by the same reference numbers, increased by 100. This embodiment differs from the embodiment of FIGS. 1 and 2 in that the frusto-conical terminal section 48 of FIG. 1 has been replaced by an inwardly directed indentation 110 of the cylinder member 101. In this case the annular closure member 106 may abut the indentation 110, so that the sealing position is defined by said indentation 110, or it is also possible that the elastomeric annular closure member 106 may be compressed to an extent it comes into contact with the terminal face 144 of the plug member 105. The indentation 110 also positions the annular plug member 105 within the cylinder member 101. The fluid filling operation and the accompanying movement of the annular closure member 106 between the sealing and filling positions are performed in the same way as described with respect to FIGS. 1 and 2.
In the embodiment of FIG. 4, analogous parts are designated by the same reference numbers as in FIGS. 1 and 2, increased by 200. The fixation of the annular plug member 205 is identical with the embodiment of FIG. 3. The cylinder member 201, however, has a constant inner diameter up to the indentation 210. An annular sealing member 209 is positioned at the identation 210 in sealing contact with the annular plug member 205 as well as with the cylinder member 201. The annular closure member 206 has an outer diameter which is equal to or greater than the inner diameter of the annular sealing member 209. After termination of the filling step, the annular closure member 206 can be brought by the abutment face 249 of the piston 203 into its sealing position with respect to the inner terminal face 244 of the plug member 205 and/or the annular sealing member 209.
FIG. 5 shows the embodiment of FIG. 4 after the annular closure member 206 has been brought into the sealing position. It is clear from FIGS. 4 and 5 that, in this embodiment, the annular closure member 206 can, if desired, be positively moved to the sealing position by the movement of the piston rod 202 and the piston unit 203. But, also, the force of the pressurized fluid in the cavity 217 after the annular closure member 206 has once been brought into sealing contact with the annular sealing member 209 could be relied upon to move the member 206 into the position of FIG. 5.
In the embodiment of FIG. 6 analogous parts are designated with the same reference numbers as in FIGS. 1 and 2, increased by 300. In this embodiment, there is provided an intermediate section 312 in the container 301, which section has a larger inner diameter as compared with the diameter of the inner cylindrical face 301a. The outer diameter of the annular closure member 306 is equal to the diameter of the internal cylindrical surface 301a and is smaller than the inner diameter of the intermediate section 312, so that a passage 314 is defined in the position of the piston rod 302 as shown in FIG. 6. This is the filling position. The piston rod 302 must be maintained in this position during filling. The filling is also here performed through the annular gap 334. After the filling step has been terminated, the annular closure member 306 is brought by movement of the piston rod 302 and the piston unit 303 into the sealing position shown in FIG. 7.
After the annular closure member 306 has been brought into the sealing position of FIG. 7, an annular indentation 315 may be worked in the cylinder member 301 to prevent the piston unit 13 from being brought into radial alignment with the intermediate section 312, thereby preventing the working chambers on the opposite sides of the piston unit 303 from being short circuited by the intermediate section 312. As will be appreciated, the indentation 315 is not necessary if short circuiting of the damping action of the piston unit 303 in the lefthand terminal position of the piston rod 302 is not a problem.
The movement of the annular closure member 306 from the position of FIG. 6 to the position of FIG. 7 can be performed by a leftward movement of the piston rod 302 from the position of FIG. 6. Also, in this embodiment, the fluid pressure in the cavity 317 can move the annular closure member 306 to the sealing position, shown in FIG. 7, when the annular closure member 306 has once been brought into contact with the lefthand end of the intermediate section 312 such that the closure member 306 is in sealing contact with the lefthand end of the cylinder member 301.
In FIG. 8 there is shown a further embodiment. Analogous parts are designated by the same reference numbers as in FIGS. 1 and 2, increased by 400.
In the embodiment of FIG. 8, the piston rod 402 is always in sealing engagement with the piston rod passage 433 by a sealing sleeve 454. The filling passage 434 is provided in this embodiment between the annular plug member 405 and the cylinder member 401. The annular closure member 406 is of elastomeric material and is in frictional engagement with the inner face 401a of the cylinder member 401. The annular closure member 406 is shown in dotted lines in the filling position. In this position pressurized fluid can enter through the gap 434. After filling, the annular closure member 406 is moved to the lefthand position, shown in full lines. This is the sealing position, in which the inner end of the gap 434 is closed. The annular closure member 406 is maintained in sealing contact with the terminal face 444 and the inner cylindrical face 401a by the pressure of the fluid in the cavity 417. The movement of the annular closure member 406 from the righthand filling position to the lefthand sealing position is accomplished by the piston rod 402 and the piston unit 403.
Although the invention has been described and illustrated herein with reference to specific embodiments thereof, it will be understood by those skilled in the art that many modifications and variations of such embodiments may be made without departing from the inventive concepts disclosed. Accordingly, all such modifications and variations are intended to be included within the spirit and scope of the appended claims. It is to be noted that in the embodiments of FIGS. 1, 2, 3, 6 and 7 the closure member 6,106,306, respectively, sealingly engages both the piston rod 2 and the inner face of the cylinder member 1, 101, 301, respectively, when said closure member is in the sealing position. Therefore the closure member fulfills also a sealing function which prevents leakage between the plug member 5 (piston rod guide unit) and the cylinder member 1. When the closure member 6 is in sealing engagement with the piston rod member 2 and with the inner face of the cylinder member 1 when being in its sealing position, it is not necessary that the closure member 6 sealingly engages the terminal face 44 for preventing leakage between the plug member 5 and the cylinder member 1. This means that also in the embodiment of FIG. 3 the closure member 6 can prevent leakage between the plug member 105 and the cylinder member 101 even if the closure member 106 is prevented by the indentation 110 from contact with the inner terminal face of the plug member 105.
If the closure member 6 does not sealingly engage the piston rod member 2 the closure member 6 can prevent leakage between the plug member 5 and the cylinder member 1 only, when the closure member 6 in its sealing position sealingly engages the terminal face 44. It is further to be noted that in all embodiments the closure member 6 is substantially exposed in axial direction to the cavity 17; with other words: there are no separating means provided within the cylinder member 1 for separating the closure member 6 from the cavity 17.
|
In the illustrative embodiments of the invention described, a pressurized fluid device of the cylinder and piston rod type includes, at one end thereof, an elastomeric closure member which is movable, under the force of the fluid to be introduced into the device, away from a sealing position with respect to the cylinder, and piston rod to a position in which the fluid is admitted into the cylinder for purposes of charging the same. Upon completion of the charging, or fluid-filling, step the closure member is returned to the sealing position either by movement of the piston rod alone or in conjunction with the action of the fluid pressure within the cylinder.
| 5
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] N/A
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
BACKGROUND OF THE INVENTION
[0003] The present invention relates to devices and methods for improving the resistance of a structure to lateral and vertical forces acting upon it. The most common sources of lateral and vertical forces acting on a structure are weather phenomena such as hurricanes, tornados, microbursts, etc. and earthquakes. Without some type of reinforcement means, most structures have relatively poor inherent resistance and are subject to significant damage from such events. For example, strong winds blowing into the sidewall of a structure will exert lateral and oblique forces against the wall and also upward forces on the roof as the forces accumulate and strengthen at building indentions, corners and roof eaves. Exterior framed structure finish veneers such as brick and concrete stucco provide mass and some resistance to lateral wind forces. Other finish veneers such as vinyl siding, EIFS and lap siding provide negligible resistance to lateral wind forces above that resistance provided by the framed structure itself. Interiors and structures are often damaged from the separation of roof decking from framing members. Wood, the most common framed structure building material, has relatively poor tensile strength. Most jurisdictions require compliance with a Building Code. Building Codes define the minimum level of structural reinforcement required to maintain structural integrity when subjected to external forces deemed possible to occur in that local area. Numerous devices and methods have been devised to improve structural resistance for use with framed structures. All of these methods and devices are designed to keep the structure intact during a violent event to maintain integrity of the structure but the devices consistently use the wood structural members for intermediate tensional resistance within the overall reinforcement concept. None of the existing concepts or devices addresses the overall structure and roof decking by connecting all of the structural and decking components with one network system that allows the entire structure and the individual components to act together to counter external forces.
FIELD OF THE INVENTION
[0004] In general, the local Building Code (or “Code”) will dictate which methods of structural reinforcement must be applied. These requirements will vary depending on the most likely event and external forces that could occur to the structure. For example, in the Gulf Coast region of the United States where hurricanes are relatively common, structural reinforcement systems typically consist of bolting or attaching wall reinforcement devices along with rafter straps or cabling, etc. attached at various points onto the framed structure. All of these reinforcements are designed to keep the roof rafters and wall studs tethered to the structure's foundation using the wood structural members as intermediate components of the concept. Codes in other areas subject not to hurricanes but to other potential external forces typically have different reinforcing methods and devices.
[0005] Although the devices of the previous examples have generally good individual component yield strength and can protect against separation of the contacting structural members, they provide minimal protection for the overall structure and no protection for the plywood roof decking covering the structure. As a result, when the weakest part of the structure or the roof decking is compromised, significant damage to the structure and contents occurs from rain and wind forces. Secondly, these devices that use wood as the intermediate tensional members are generally not capable of withstanding very strong wind events and many structures are still damaged each year.
[0006] What is needed in the art is a cost-effective means for protecting the integrity of the roof decking while at the same time, substantially increasing the resistance of the entire framed structure and decking to separation.
[0007] What is also needed in the art is a means for dramatically improving the strength of a framed structure without requiring a substantive change to the method or materials of construction.
[0008] What is also needed in the art is a standardized, engineered solution that differentiates varying external forces and prescribes standard components in varying ways to protect an entire framed structure and all components including wall sheathing and roof decking.
BRIEF SUMMARY OF THE INVENTION
[0009] The present invention is a reinforcing system applied to an entire structure that when installed, greatly increases the structure's resistance over prior methods yet can be applied affordably. The principal behind the present invention is that, when interconnected, a series of binding elements is stronger than that of each individual element attached at various points in a framed structure. An additional principal is that the framed structure is being structurally reinforced without using framed members having low tensile strength as part of the reinforcement system. The invention is comprised of plurality of strapping elements placed on top of the roof decking of a structure, extending down the side walls of the structure, and attached to the structure's foundation. Each strapping element is tensioned after being set in place. Once all of the strapping elements are in place and tensioned, the straps are secured to the structure at various locations and at points where the straps intersect. Once fastened together, the straps form an extremely strong web of reinforcement throughout the entire the structure. Resistance to wind loads, for example that may be applied to only one side of the house are actually spread throughout the entire structure due to the network of interconnected straps. Thus, the structure's integrity cannot be lost by the failure of any one element as is typical with devices that are attached at various points in a framed structure.
[0010] The present invention is an engineered product, which means that the number of straps, location of the straps, and the fastening points to the structure must be determined by a trained person for each particular structure and the Building Code requirements for the area where the structure is located. In general, the more straps and the more fastening points, the greater the overall network resistive strength will be achieved. To assist in understanding the methodology of applying this system, a four-sided structure is used. However, one skilled in the art can apply the basic principals of the 4-sided structure example to cover other structural layouts.
[0011] The basic element of the system is the strap. Each complete strap is comprised of two “foundation” straps and a “runner” strap. Each foundation strap has one end embedded into or otherwise attached to the structure's foundation. The other end of the foundation strap is connected to one end of the runner strap. The runner strap is placed up the outside of the sidewall, through a slit in the roof decking, up over the top of the roof decking, and down the opposite side wall. One end of the runner strap is connected to the foundation strap without tension using various metal strapping means. Using a standard strap-tensioning tool, the end of the opposite foundation strap is set into the device and the opposite end of the runner strap (coming down from above) is set into the device. The device is ratcheted to pull the runner and foundation straps together to a prescribed minimum tension. Once under tension, the pieces are attached together and the tensioning device is removed. Once all of the straps are tensioned, the straps are “networked” by fastening them at various points to the roof structure and at strap crossing points.
[0012] It is an object of the invention to provide a structure stabilizing system that includes a plurality of interconnected, pre-tensioned straps.
[0013] It is a further object of the invention to provide a structure stabilizing method that presents a simple approach to designing and installing a network of interconnected, tensioned straps to accommodate a wide range of building types, sizes and roofing configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 shows a three-dimensional view of a four-sided structure with a typical strapping design that includes examples of methods for larger than standard openings and a framed attachment to the main structure.
[0015] FIGS. 2A , 2 B and 2 C show types of foundation sections of various strap assemblies, which are embedded into the foundation's slab or stemwall foundation.
[0016] FIGS. 3A , 3 B and 3 C show alternate embodiments of foundation sections and various strap assemblies where the structure does not have a concrete slab such as found with structures built on pilings or piers.
[0017] FIGS. 4A and 4B show an alternate embodiment of a foundation section where one end is attached to an anchor bolt as might be done for retrofit applications or interior wall anchors.
[0018] FIG. 5 shows a side cross-sectional view of a strap where it exits the top of the roof decking and extends below the decking, down the sidewall of the structure.
[0019] FIGS. 6C-6D show various pre-tensioning roof attachments for situations such as roof valleys.
[0020] FIGS. 6A-6B show various post-tensioning roof attachments for situations such as roof apexes.
[0021] FIGS. 7A , 7 B show typical attaching means for securing various types of tensioned straps to the roof structural members.
[0022] FIGS. 8A , 8 B and 8 C show details of various runner strap sections.
[0023] FIG. 9A-9J show details of typical joining methods for runner and foundation sections of the various straps that can be used before and after applying tension using a tensioning tool.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In reference to FIG. 1 , a standard 4-sided structure with an angled roof and eave is shown with the strapping system of the present invention in place. Item 1 represents the standard strap spacing determined by the installer based upon the degree of resistance desired or required by local Building Codes. The inventors have determined that 3 to 10 feet spacing will be adequate for most Code requirements and external forces to be expected in the United States. The shorter the standard spacing, more straps will be present for a given building dimension and greater structural resistance will result. For example, 3-feet spacing may be required to protect a structure directly on the coast, which may be subject to the highest wind force of a hurricane. However, greater standard spacing may be desired further inland as hurricane winds tend to decrease once the storm moves further over land.
[0025] The strapping system of this typical structure is designed by first locating the end-wall strap spacing 7 placed within a minimal distance from the outside wall corner. Then, moving toward the opposite wall, the next strap is placed at the standard spacing 1 except when interferences occur. This procedure is repeated for the other two walls resulting in a grid-type layout over the structure. The straps that are placed on standard dimensions that extend down over an opening into the structure's wall, such as a door or window, are then moved according to several standard adjustment formulas. Straps that interfere with openings may be spaced closer than standard as shown by spacing 5 . The inventors set forth herein the preferred adjustment means for the most typical of structural openings. The methodology behind these formulas are exemplary and can be applied to other wall openings as well.
[0026] The first adjustment formula applies to a window opening 4 that is greater than the standard spacing dimension determined for the structure. In this instance, one end of the strap is placed on the edge of the window opening while the other end of that strap is located at the next forward strap location. A second strap is located on the other edge of the window opening with the other end extending to the preceding adjacent strap location. The strap spacing on the wall opposite the wide window 4 is maintained at standard spacing 1 . This design formula results in these two adjacent straps forming an “x” pattern 9 over the structure whereas most other straps between two opposite side walls will be parallel. The “x” pattern 9 allows multiple connections to roof structural members, providing greater overall strength, as the runner strap passes over these structural members on a diagonal.
[0027] A second adjustment formula is applied to a garage opening 6 where the opening dimension is more than 2-times the standard spacing dimension. In this instance, a standard spacing dimension 1 is marked on the opposite wall from garage bay opening having a center located directly across from the opening's center. One strap is located on one edge of the garage bay and extends over to the structure's roof to 11 . A second strap is located at the other edge of the garage bay and extends over the structure's roof to 12 . Additional straps that are located at the garage opening edge run directly across the roof structure and connect to foundation straps on both ends. All four garage bay edge straps are connected with fasteners to the horizontal opening structural member. A third strap is secured to the horizontal structural member at the center of the garage opening and extends directly across the roof structure to the opposite sidewall. This design formula results in these two adjacent straps forming an “x” pattern 8 over the structure with a third strap centered in between.
[0028] In continued reference to FIG. 1 , an entrance-way appurtenance 15 is shown on the forward wall. This typical entrance-way is comprised of a 3-sided structure and covering roof extending away from the main 4-sided structure of the building. Straps 14 , which secure the main structure are connected to the foundation and extend down the outside wall of the main structure, behind the wall of the entrance-way appurtenance 15 . This entrance-way appurtenance 15 is reinforced by a single strap 10 placed over the appurtenance roof near the forward edge. The purpose of placing this appurtenance strap close to the edge is the separation of the appurtenance's roof structure from the stud wall is most likely to happen from vertical forces pushing up on the forward eave of the appurtenance. Therefore, the tie-down force should be applied as close to the forward wall edge as practical to secure that area. Longer appurtenances may be secured with more than one strap. Chimney and porch appurtenances are also secured in a similar manner.
[0029] As a practical matter, the location and placement of the straps are typically performed graphically by an architect or engineer with strap spacing adjustments made for openings in the side walls. Once the initial structural grid and sidewall opening adjustment formulas have been applied, a drawing is marked and given to field personnel to begin marking the foundation structure at the determined locations and installing the foundation straps.
[0030] In reference to FIGS. 2A , 2 B and 2 C, an embodiment of a foundation section is shown for new construction applications. This foundation strap is further comprised of an embedding section 20 and an attachment section 21 . The embedding section of a metal strap or bracket 20 is typically coated with a material that prevents corrosion by the concrete material of the foundation slab 22 . This section is also bent at various locations to form a general “hook” shape that provides increased strength of attachment once embedded into cured concrete. An additional area of the metal portion of the strap base 21 approximately 18″ above the embedded portion is coated to prevent any moisture below grade or weeping from the wall or mortar from a brick wall system degrading the strap strength. A metal strap will have holes along its length suitable for nails, screws, bolts, or other fasteners to attach the strap to framing members to secure the strap at critical framing changes or unusual structural components. The attachment metal section 21 may have two additional small holes 24 located near the first bend for proper positioning and insertion of nails or other fasteners to secure the strap to the concrete form. The metal strap has additional holes that allow the strap to be easily attached to the bottom wall plate and to the wall stud 23 and further secure the wall structure to the foundation. The attachment strap section need only be a few feet long and can be coiled up and set on the ground until the framing crews complete the basic wall and roof structure construction. FIG. 2C shows an alternate embodiment of the foundation section using a non-rigid strap material. To facilitate positioning and shaping of the non-rigid material during installation, a rigid bracket 31 is used with the flexible strap material to hold the strap at the proper shape when the foundation is poured.
[0031] In reference to FIGS. 3A , 3 B and 3 C, an alternate embodiment of a foundation section of a strap assembly is shown for structures without a concrete slab. The foundation strap 3 B is also further comprised of a foundation section 20 and an attachment section 21 . The foundation section 20 contains two pairs of holes 26 for receiving a pair of securing bolts or other type fastener. This foundation section is bent at two locations to form a general “U” shape of width 28 that conforms to the supporting structure 25 dimensions. The attachment section 21 has holes located along its length for insertion of nails or other fasteners to secure the strap to the bottom plate and wall stud 23 and further secure the wall structure to the supporting foundation structure. The foundation strap 3 C made from alternate materials would require a rigid bracket base section 31 similar to strap 3 B to reinforce the attachment to the foundation. The attachment section need only be a few feet long to provide a working length for attachment to the matching strap runner coming down the sidewall from above.
[0032] In reference to FIGS. 4A and 4B , an alternate embodiment of a foundation section of a strap assembly is shown for retrofit applications to existing slabs or for anchoring interior wall straps. This type of foundation strap is field fabricated from a runner strap and has a short end piece bent at 90° and has a central hole for attachment to a standard concrete anchor 29 . The central hole in the strap is placed over the threaded end of the concrete anchor 29 and the nut fastener with washer is attached.
[0033] Once all of the foundation straps are in place at the locations determined by the system design and framed construction is complete to the point of roof decking and outer walls, the matching runner straps are installed over the roof decking of the structure and extended down the sidewall of the structure through the roof decking. In reference to FIG. 5 , a typical strap routing is shown for a structure with an eave extending out away from the wall stud. In this case, a slit 50 is cut into the roof decking flush with the outside edge of the wall stud 23 . To avoid compression of the roof decking when the straps are tensioned, a framing block 52 is inserted underneath the roof decking behind the strap and secured to structural members. One end of the runner strap 53 is inserted through the slit 50 and extended down far enough to reach the matching foundation strap at the base of the wall stud.
[0034] After the straps are placed over the roof decking and extended down the sides of the stud walls, just prior to joining and tensioning the runner and foundations strap sections, certain runner straps must be anchored. Primarily, these include runner straps crossing roof valleys.
[0035] FIG. 6C shows a securing system for a typical roof valley 69 employing a formed sheet metal frame 64 that is inserted around the valley structural member 69 . The formed frame employs two flat sections abutting the underside of the roof decking on either side of the valley. A hole is drilled through the roof decking and a pair of bolt-type fasteners 62 are inserted and tightened, which secures the strap in 3 places across the gable. FIG. 6D shows an alternate valley-securing system comprised of a central bolt 65 securing the strap to the valley structural member and a pair of screw type fasteners 66 securing the strap to the roof decking and framing blocks 67 underneath the roof decking on either side of the roof valley.
[0036] Once the valleys are secured, the straps are ready to be tensioned. From the ground around the structure, the installer joins one end of the runner strap to its related foundation strap by any number of standard metal strapping means. The installer then inserts the opposite loose end of the runner section into a common strap-tensioning tool. The loose end of the foundation strap is also inserted into the strap-tensioning tool. The straps are then pulled together to provide a permanent tension force to the entire runner/foundation strap. The inventors estimate that 50-200 ft-lbs of tension would be adequate for most applications although more or less tension could be applied in special circumstances. A “proper tension-over tension” gauge is used to determine that minimum tension has been reached while also confirming that the strap has not been over tensioned. The uniformity of tension levels through the strap network insures proper performance of each strap. The gauge will be incorporated into each strap at the tensioning location and remain visible for inspection. While under tension, the runner and foundation straps are connected together by any number of standard metal strapping attachment means. When valley points are secured on a roof, the tensioning and joining must take place at both ends of the runner and foundation straps ground locations.
[0037] Once the individual straps are tensioned, the system is networked together by fastening the runner sections together at crossing points and fastening the runner sections to the structure. In general, the more fastening points of the tensioned strap network to the structure, the greater reinforcement properties of the system. The critical attachment points to the structure are the roof apex ridge, roof rafters and wall studs. The installer will typically apply structural fasteners into the roof decking at every point where two or more straps overlap. FIG. 1 shows a typical attaching point 13 where two perpendicular straps intersect. The fastener is installed through the straps and into the roof decking. FIG. 7A shows a typical fastener 70 installed through the strap, through the roof decking, and into the roof rafters. FIG. 7B shows an attaching means for two straps that intersect between two adjacent roof rafters. The bolt or other similar fastener 71 is inserted through the straps at the point of intersection, through the roof decking and through a framing block 72 placed between and secured to the roof structure. Additional fasteners will then be installed where straps cross roof rafters and apex ridges. The most basic attachment means involves the use of a screw or nail 60 , as seen in FIG. 6A , that secures the strap to the apex structural member 68 . An alternate attachment means can be a bolt and nut assembly 61 , as shown in FIG. 6B . The bolt is inserted through a hole in the strap and extending through the apex structural member 68 . A nut is then placed on the end of the bolt and tightened. Still more fasteners will be installed on the vertical part of the runner straps securing the strap to the top and bottom plates and vertical studs. Fasteners may also change depending on the strap material. For example, a non-rigid metallic steel mesh or nylon strap would not have pre-drilled holes in the strap material. These type straps would be fastened to the roof decking and rafters using screws with washers.
[0038] FIG. 8A shows the detail of a metal runner section 80 of a strap having a width 83 and a plurality of pre-drilled holes 84 , spaced apart a distance 82 , and spaced from the strap's edge a distance 81 . Metal straps are typically made of 10 to 32 gauge galvanized steel of width between 0.5 to 4.0 inches. As a general matter, different steel compositions and heat treating operations will be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. The pre-drilled holes allow for rapid installation of fasteners by the installer. The holes are offset a distance 81 from the side at least ¼″ to maintain strength of the attachment. The holes 84 are spaced apart a distance 82 of approximately 1-2 inches. The holes 84 are staggered to allow more variety of location and improve the number of points where the holes align over the roof and wall structural members. Coating methods, such as galvanizing, may be applied to metal strapping in specific climate zones where air contaminants could cause corrosion and degradation of the strap material. Non-corrosive metal materials such as stainless steel of varying grades may be utilized in more corrosive atmospheres.
[0039] FIG. 8B shows the detail of a non-metallic plastic, fabric or other non-metallic material runner section 80 of a strap having a width 83 . Non metallic straps are typically made of plastics and fabrics made of nylon, fiberglass, Kevlar, dynema, polyethylene, polypropylene, polyvinylchloride or similar materials and having the ability to be formed by extrusion or woven into a strap formation. The strap would have a width between 0.5 to 4.0 inches and thickness between 3 mil (0.003 inches) and 250 mil (0.250 inches). As a general matter, different non-metallic materials or combinations of non-metallic materials in a matrix may be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. Connection points of the strap and the network into the roof and wall structural members is easier with non-metallic straps as the penetration at any point through the strap does not require pre-punched holes. Metal reinforcing washers and brackets at certain attachment positions would be required to reinforce those attachment points when utilizing non-metallic straps.
[0040] FIG. 8C shows the detail of a non-metallic plastic, fabric or other non-metallic materials runner section with integral wire reinforcement 85 of a strap having a width 83 . Wire reinforced non metallic straps or wire mesh or rope straps are typically include plastics and fabrics made of nylon, fiberglass, Kevlar, dynema, polyethylene, polypropylene, polyvinylchloride or similar materials and having the ability to be formed by extrusion or woven and include within the extruded or woven strap formation also includes a matrix of wires of various metallic materials. The percentage of metallic wires could increase to 100% of this embodiment to manufacture a strap totally of wires formed in a mesh or rope that then could be flattened for suitable installation on the vertical wall and across the roof decking of a framed structure and not interfere with the installation of other overlapping components such as wall siding or roofing shingles. The strap would have a width 83 between 0.25 to 4.0 inches and a final installed thickness between 3 mil (0.003 inches) and 250 mil (0.250 inches). As a general matter, different non-metallic materials or combinations of non-metallic materials plus more metallic wire reinforcement may be used to provide stronger straps. Also the wider and thicker the strap, the greater will be the yield strength and the stronger the individual strap and the network strength. Connection points of the strap and the network into the roof and wall structural members is easier with wire mesh, wire rope or wire reinforced non-metallic straps as the penetration at any point through the strap does not require pre-punched holes. Metal reinforcing washers and brackets at certain attachment positions would be required to reinforce those attachment points when utilizing straps incorporating these materials.
[0041] There are several methods suitable for joining the runner and foundation straps before and after applying tension. The tensioning tool pulls the straps along side each other until the correct tension is established. In FIG. 9A , a crimping and folding tool cuts a plurality of notches 90 through both straps and bends the notched strap material over and compresses the metal together. The notches are rotated 180 degrees to provide attachment resistance in multiple directions.
[0042] FIG. 9B shows an alternative attaching means using a banding strap 91 that is inserted over the tensioned straps and crimped using a special tool. Multiple banding straps are applied to ensure a strong connection. FIG. 9C shows an additional attachment means employing a buckle 92 . The end of each strap is threaded through the buckle holes and aligned. When axial tension is applied, the friction caused by contact between the straps and the buckle metal will hold the straps together. FIG. 9D shows an additional attachment means comprised of a plurality of fasteners, such as bolts or rivets, 93 inserted into overlapping straps 80 . The holes in the two straps are aligned and the fasteners inserted and secured. FIG. 9E shows an alternative fastener embodiment where screws 94 are used to secure straps 80 into a cross beam 96 inserted and secured between to wall studs 95 . FIG. 9F shows an alternate attaching means employing an adhesive 96 placed between the straps that once cured forms a strong bond between the straps. FIG. 9G shows an alternate attaching means comprised of a mesh sock 98 into which both ends of the runner and foundation straps are placed. When axial tension is applied to the mesh sock, a proportional gripping force is applied to the inserted strap ends holding them together. FIG. 9H shows an alternate attaching means comprised of a tension buckle 99 with hooked ends that are inserted into holes on the straps. When connected, the tension buckle is turned. By screw action, each hook end is pulled toward the buckle center applying tension to the straps. FIG. 9I shows an additional attachment and tensioning means employing a ratcheting turnbuckle 100 . Each end of the straps is inserted into a slot located in the center barrel of the turnbuckle. As the turnbuckle is ratcheted, the center barrel turns, wrapping the straps from different directions and pulling the straps together. Once the desired tension is applied, a set pin is positioned to keep the center barrel immobile and the turnbuckle ratchet handle is moved to the rest position. FIG. 9J shows an additional attachment using a sleeve 101 that is placed around the straps 80 to be joined that includes one or more set-screws 102 that are threaded into and secure the two internal straps by pressure of the sets screws against the straps and the sleeve base.
|
A network of straps is placed over a framed structure and roof decking and secured to the foundation. A tensional force is applied to the straps. The tensioned straps are then secured at strap crossing points, the roof decking, roof structural members and wall structural members. The method also provides special treatment for straps crossing apex ridges or valleys of the structure's roof. Additional framing blocks are included under the roof decking to accommodate fastening the straps to the primary structural members. The runner straps pass through slits cut into roof decking near where the sidewalls attach to the roof joists and rafters. An added framing member or supporting structural device is also installed above the top plate of the stud wall to support the roof decking as tension is applied to the straps. The method calls for determining standard strap spacing based on the design resistance required to counter external forces that could be encountered at the construction location. The straps are placed on all sides at the standard spacing. Special adjustments to the spacing are made to accommodate larger than standard spacing door, garage, and framed openings. The number and configuration of straps is dependent on Building Codes and engineered design guidelines. By securing the strap network to the structure under tension, the strap network provides a distributed resistance force throughout the entire structure greatly enhancing its strength against external winds, internal vacuums, and earthquakes. Suitable straps can be fabricated from range of materials and composites such as metallic and non-metallic banding, a combination of non-metallic banding with wire reinforcement, wire mesh or wire rope.
| 4
|
BACKGROUND OF THE DISCLOSURE
1. Field of the Invention
The present invention is directed to an electromechanical (MEMS) device which utilizes a working fluid and a process of making the same. More specifically, the present invention is directed to a MEMS device which utilizes a working fluid having a size no greater than about 10 microns wherein the working fluid is a high pressure liquid or a supercritical fluid and a process of making a MEMS device which involves introducing a high pressure liquid or a supercritical fluid therein.
2. Background of the Prior Art
The development of MEMS devices has significantly advanced in recent years. This development corresponds to the extensive growth in the use of integrated circuits involving semiconductor devices. Although the development of MEMS devices has rapidly developed in recent years, advances in MEMS devices requiring the utilization of a working fluid has been slower. This is because of problems associated with the inability of the working fluid to traverse through openings provided in the MEMS device.
The aforementioned problems have become more pronounced with the development of MEMS of ever decreasing size. Obviously, as newly developed integrated circuits become smaller and smaller, MEMS devices, employed in applications involving integrated circuits, have been required to correspondingly decrease in size. Although the development of MEMS devices of smaller and smaller size has continued apace, as evidenced by such developments as those embodied in U.S. Pat. Nos. 6,164,933 and 6,227,809, which describe micropumps, and U.S. Pat. No. 5,323,999, directed to a micro-sized gas valve, a major deterrent to this development is the constraint provided by the inability of working fluids to flow in micron-sized and even nanometer-sized devices. This is because, as those skilled in the art are aware, of the inability of working fluids to penetrate into such tiny-sized spaces. This, in turn, is the result of the relatively high surface tension of most working fluids. That is, the higher the surface tension of a fluid, the more difficult it is for that fluid to traverse through a very small sized opening.
The technical literature has addressed this problem in the development of MEMS devices. Burger et al., 14 th IEEE Inter. Conf. Micro Electro Mechanical Systems, 418-421 (January, 2001) describes a cryogenic micromachined cooler suitable for cooling from ambient temperature to 169° K. and below. The working fluid in this MEMS cooler device is ethylene which is present as a liquid and a gas. The MEMS cooler, however, is attached to a source of ethylene and the system is required to be sealed off in order to maintain specific thermodynamic conditions necessary to retain ethylene under conditions required for cryogenic operation.
Although this cryogenic MEMS machine represents an improvement in MEMS heat exchange technology, it does not provide the requisite mobility, requiring as it does the presence at all times of a source of fresh working fluid, necessary to extend the utility of MEMS devices requiring a working fluid to very small sized devices.
It is thus apparent that there is a significant need in the art for a new MEMS device which utilizes a working fluid, which need not be tethered to a source of the working fluid, having a low enough surface tension so that it can be used in the ever smaller sizes required of newly developed MEMS devices.
BRIEF SUMMARY OF THE INVENTION
A new MEMS device requiring the use of a working fluid and a method of producing the same has now been developed which is characterized by the use of a working fluid having very low surface tension such that the MEMS device may be as small as nanometer-sized. The MEMS device provided with a working fluid, although capable of flowing through all openings provided in the MEMS device, is also characterized by the self contained nature of the working fluid. That is, the MEMS device is unattached to any working fluid source, representing as it does a true closed loop system, wherein the working fluid provides the same operability associated with MEMS devices of the prior art which require an appended working fluid source.
In accordance with the present invention a microsized MEMS device which utilizes a working fluid is provided. The working fluid is a high pressure liquid or a supercritical fluid. The MEMS device is provided with a connecting device which not only acts to permit introduction of the working fluid under thermodynamic conditions consistent with the maintenance of the fluid in the liquid or supercritical state but which maintains the fluid under those conditions even after removal of those thermodynamic conditions.
In further accordance with the present invention a process of providing a MEMS device having a size no greater than about 10 microns utilizing a working fluid is provided. In this process a high pressure liquid or a supercritical fluid is introduced into the micron-sized MEMS device utilizing a working fluid under thermodynamic conditions consistent with the maintenance of the working fluid in the liquid or supercritical state. High pressure liquid or supercritical fluid is introduced into the MEMS device until the pressure of the liquid or supercritical fluid in the MEMS device reaches the pressure of the liquid or supercritical fluid source. Thereupon, a device provided in the MEMS device closes and seals the working fluid in the MEMS device from the source, trapping the working fluid therein. The thermodynamic conditions are thereupon changed to ambient. However, the working fluid in the MEMS device remains in the liquid or supercritical state.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be better understood by reference to the accompanying drawings of which:
FIG. 1 is a schematic representation of an apparatus suitable for introducing a high pressure liquid or a supercritical fluid into a MEMS device; and
FIG. 2 is a schematic representation of an aspect of a MEMS device illustrating means for introducing a liquid or a supercritical fluid therein.
DETAILED DESCRIPTION
A MEMS device which requires the utilization of a working fluid is depicted by reference numeral 16 . During introduction of the working fluid MEMS device 16 is disposed in a filling zone 14 of a processing chamber 12 . Therein a high pressure liquid or supercritical fluid from a source 30 is introduced into device 16 . To ensure that the liquid or supercritical fluid remains in the liquid or supercritical state during introduction, thermodynamic conditions in processing chamber 12 are maintained under conditions which insure retention of the fluid in the liquid or supercritical state. Those thermodynamic conditions are a function of the physical characteristics of the working fluid. For example, when the working fluid is carbon dioxide, neon, nitrogen, argon, xenon, sulfur hexafluoride or propane, processing chamber 12 is maintained at a pressure in the range of between about 1,000 psi and about 8,000 psi. More preferably, the pressure within the processing chamber 12 is in the range of between about 2,000 psi and about 5,000 psi. At this pressure an additional fluid, ammonia, may be utilized. Still more preferably, the pressure within processing chamber 12 is about 3,000 psi. It is at this pressure that the most preferred working fluid, carbon dioxide, is most usefully employed. The temperature within processing chamber 12 is maintained in a range of between about 32° C. and about 100° C. Preferably, the temperature within processing chamber 12 is maintained in a range of between about 50° C. and about 80° C. Still more preferably, the temperature within processing chamber 12 is in the range of about 70° C.
Since it is critical that the aforementioned thermodynamic conditions be maintained during the filling of the working fluid into the MEMS device 16 , processing chamber 12 may be controlled by a heat controller 32 which has the capability of monitoring the temperature therein by means of a thermocouple 26 . The measured temperature is adjusted by heat jacket 18 , controlled by controller 32 , in accordance with temperature control means well known in the art.
As stated above, a high pressure liquid or supercritical fluid is introduced into MEMS device 16 , disposed in filling zone 14 of processing chamber 12 . This fluid, introduced into MEMS device 16 , is provided by a liquid or supercritical fluid source 30 . As shown in FIG. 1, the liquid or supercritical fluid source 30 may be prepressurized by a pump 28 , disposed downstream of the source of the liquid or supercritical fluid 30 . The high pressure liquid or supercritical fluid is conveyed into filling zone 14 of processing chamber 12 by means of a connecting means 36 provided as part of MEMS device 16 as discussed below.
Turning now to the MEMS device 16 , that device is disposed in processing chamber 12 , which, as indicated above, is maintained under conditions which are suitable for the maintenance of the working fluid in the liquid or supercritical state. The MEMS device 16 includes a plurality of conduits 37 into which a liquid or supercritical fluid is introduced. The liquid or supercritical fluid is introduced through a connecting means 36 provided on the device 16 . The connecting means 36 operates on the principle of a check valve. Indeed, a check valve suitable for introducing a liquid or supercritical fluid into a MEMS device is described in copending U.S. patent application, Ser. No. 09/915,786, filed Jul. 26, 2001, incorporated herein by reference.
It is emphasized that check valve designs other than those set forth in copending U.S. patent application, Ser. No. 09/915,786, filed Jul. 26, 2001, as the connecting means 36 component of MEMS device 16 , wherein the check valve principle, underlying the embodiments detailed therein, may be utilized.
The introduction of a liquid or a supercritical fluid into MEMS device 16 in processing chamber 12 is completed when the pressure of the high pressure liquid or supercritical fluid in MEMS device 16 is equal to the pressure of the source 30 . At this point the MEMS working fluid, the liquid or supercritical fluid, is fully charged into MEMS device 16 . Thereupon, in accordance with the operation of connecting means 36 , as discussed in copending U.S. patent application, Ser. No. 09/915,786, the conduit between the source of liquid or supercritical fluid and the MEMS device 16 is closed by the closing of a plug in connecting means 36 trapping the working fluid therein. Thus, the working fluid is held in MEMS device 16 at the pressure of its introduction. Therefore, the next step, the removal of thermodynamic conditions consistent with the maintenance of the working fluid in the high pressure liquid or supercritical fluid state, does not change the state of the working fluid in MEMS device 16 insofar as that fluid is trapped therein under the pressure at which it was introduced therein. Stated differently, the replacement of the thermodynamic conditions consistent with the maintenance of high pressure liquid or supercritical fluid conditions in processing chamber 12 with those of ambient does not change the pressure of the liquid or supercritical working fluid in MEMS device 16 . Hence, the working fluid remains a liquid or supercritical fluid.
Examples of MEMS devices requiring a working fluid, within the contemplation of the present invention, include a heat exchanger, a closed loop pumping apparatus, a closed loop hydraulic system and the like.
The MEMS device, as suggested previously, is no larger than micron-sized. That is, the size of the MEMS device is no larger than about 10 microns. More preferably, the maximum size of the MEMS device is no larger than about 1 micron.
The above embodiments are given to illustrate the scope and spirit of the present invention. These embodiments will make apparent, to those skilled in the art, other embodiments and examples. These other embodiments and examples are within the contemplation of the present invention. Therefore, the present invention should be limited only by the appended claims.
|
An electromechanical device having a size no larger than about 10 microns utilizing a working fluid in the high pressure liquid or supercritical fluid state. A process of preparing the electromechanical device involves the introduction of the liquid or supercritical fluid therein which permits the retention of the working fluid in the liquid or supercritical state after introduction.
| 5
|
FIELD OF THE INVENTION
[0001] The present invention relates to a safe, convenient, stowable and readily deployable structure for holding and stabilizing one or two long weapons such as shotguns or rifles for leisure and sport shooting, and more specifically a handy support system which will save lives, protect expensive and highly finished shotguns and rifles, and will not fall into disuse because the rest can be deployed and stowed in two easy steps.
BACKGROUND OF THE INVENTION
[0002] Structures which support rifles and shotguns are typically employed at shooting ranges and other locations where a shooter is generally expected to stand in one place or near a fixed location for extended periods of time. Skeet ranges illustrate one example, where the shooter is either engaged in holding a shotgun during shooting or is not shooting, seeks to put the shotgun down and may usually have available a specialized rack for cradling and holding the shotgun.
[0003] However, in more rustic settings no such specialized cradling structure will be available. As a result, shooters will tend to put the rifle or shotgun down by leaning it against some other structure, if available. Shooters typically will not lay the weapon flat on the ground unless necessity dictates. The dangers of the tendency to lean the weapon on an unstable object are well known. When the weapon is leaned upon a vertical object which is horizontally flat with regard to movement to either side, the resulting surface contact is quite small, usually a minute tangential contact between the circular outer portion of the barrel and a vertical planar surface, if available. Even worse, the barrel of the weapon may be leaned against a small tree or post. A gust of wind could cause it to fall and possibly discharge.
[0004] The vertical storage position is generally safe, so long as the weapon will not shift or fall. Most structures which could provide adequate support are heavy and bulky. A shooter who might walk to a remote location would find it difficult to carry in a conventional base stand.
[0005] In the most extreme cases shooters who backpack into remote areas have no commercially available device for supporting their weapons. For any device to be commercially viable for carriage while backpacking, it must be lightweight, stowable to a small volume, and readily deployable. The ability for any support device to find acceptance in this most severe environment where any additional weight and space must be justified, represents a challenge.
[0006] One support for fishing rods which has been of some advantage is a fishing rod holder described in U.S. Pat. No. D 471,952 issued on Mar. 18, 2003 to John Cardenas and which is incorporated by reference herein. This single piece wire rod having a step shield was found to be advantageous for fishing. This structure was between four and five feet high and was suitable generally for carriage along with other fishing equipment in a vehicle, and possible attached to fishing rods and poles. The length of the fishing rod holder would cause it to be difficult to backpack for any amount of time and would probably not be as selectable for either backpacking or any trip which involved overland manual carriage of equipment. Further, the fishing rod holder was a one piece structure made of solid wire, and was structurally sound though somewhat heavy. However, the fishing rod holder solved many problems including (1) it avoided laying the fishing rod on the ground or mud while waiting for a fish take the bait, (2) it avoided causing the fishing rod holder to be pulled forward before recoiling back, since it was supported high, and (3) it avoided damage to the fishing rod from being pulled into the water where a makeshift support could not fully stabilize the rod.
[0007] What is needed is a system which is lighter and which takes advantage of common structural components between a fishing rod support holder and a shotgun and rifle support which would encourage greater use and greater safety by providing such support structures in a form and configuration which facilitates their carriage. The needed system should recognize the fact that fishing and target practice or shooting is not generally expected to occur simultaneously. The needed structure should provide stowage and deployment capability such that both capabilities may be taken along, or that one capability may be taken along when it is known that the other capability will absolutely not be needed.
SUMMARY OF THE INVENTION
[0008] A deployable stowable shotgun/rifle rest & fishing rod holder includes a common lower section which may preferably be hollow tubular construction and having a pinched tip for resistance to any deformation upon being inserted into the soil. A triangular shaped symmetrical piece of sheet metal is attached to the lower section which includes upper angled portions for providing a step assist upon insertion into the soil. The triangular shaped symmetrical piece of sheet metal provides additional resistance to tipping and enables the user to generally avoid the necessity to apply a striking force to the structure.
[0009] Insertable into the common lower section is an upper section deployable and stowable shotgun/rifle rest or a fishing rod support. The use of a common lower section enables a three piece system in which a user can (1) carry all three pieces either by backpack or by automobile, for ready deployment, or (2) simply select a lower section and one of the upper sections for carriage and deployment. Cleaning the deployable stowable shotgun/rifle rest & fishing rod holder is a simple task. All a user would need do is brush off or tap lower section remove any soil present, and all of the structures can be wiped clean. The deployable stowable shotgun/rifle rest & fishing rod holder can be made of stainless or carbon steel. The deployable stowable shotgun/rifle rest & fishing rod holder can also be coated with powder coat, nickel plating, and chrome plating. All of the above make the deployable stowable shotgun/rifle rest & fishing rod holder impervious to rust or corrosion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The invention, its configuration, construction, and operation will be best further described in the following detailed description, taken in conjunction with the accompanying drawings in which:
[0011] FIG. 1 is a perspective view of an assembled shotgun/rifle rest;
[0012] FIG. 2 is a perspective of the assembled fishing rod holder, with a portion of a fishing rod shown in dashed line format;
[0013] FIG. 3 is a perspective view of the assembled shotgun/rifle rest seen in FIG. 1 shown with a pair of weapons, a rifle 91 and a shotgun 93 supported by the rest; and
[0014] FIG. 4 is an exploded view of both upper sections and the lower section shown in the non-deployed state as a kit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] The inventive deployable stowable shotgun/rifle rest & fishing rod holder is a three main component system which includes a lower section which can be driven into the ground, and an upper shotgun/rifle rest section which can be attached to the lower section to form a shotgun/rifle rest and an upper and fishing rod holder section which can alternatively be attached into the lower section to form a fishing rod holder. An explanation of the invention will be best initiated with respect to FIG. 1 which illustrates an overall assembled view of the shotgun/rifle rest assembly 21 .
[0016] Shotgun/rifle rest assembly 21 includes a lower section 23 which includes a lower tube 25 which is preferably a hollow metal tube having a lower tip 31 . Just above lower tip 31 is a flattened area 33 for hardening and reducing the cross section area near the lower tip 31 and for transitioning to a circular or oval tubular cross section which exists just above the flattened area 33 . A triangular shaped symmetrical piece of sheet metal 35 is attached to the lower tube 25 . The triangular shaped symmetrical piece of sheet metal 35 has a centerline which is generally parallel to the lower tube 25 and tapers in the direction of tip 31 . The upper edges of the a triangular shaped symmetrical piece of sheet metal 35 on either side of the lower tube 25 have angled portions 37 which present a slightly greater width than the thickness of the a triangular shaped symmetrical piece of sheet metal 35 to enable a user to use foot pressure to help push the tip 31 further into the ground.
[0017] At the upper part of FIG. 1 , an upper section 41 of shotgun/rifle rest assembly 21 is seen. Upper section 41 includes an upper tube 43 . The lower end of upper tube 43 is seen as having a smaller diameter than and is fitted into the lower tube 25 . It is equally possible to have the lower end of upper tube 43 to have a larger diameter than and be over fitted onto the lower tube 25 . At the top of the upper tube 43 , an “S” shaped fitting 45 . Each half of the “S” shaped fitting 45 provides an encircling horizontal shape to stably cradle a shotgun or rifle resting against the shotgun/rifle rest assembly 21 . As a result of the geometry of the “S” shaped fitting 45 and the moment about the upper tube 43 , the connection between the upper tube 43 and lower tube 25 should not allow the upper tube 43 to turn with respect to the lower tube 25 . Also seen is a plastic or rubber coating 49 which is shown covering the “S” shaped fitting 45 and partially downwardly over about two to three inches of the upper tube 43 . The plastic or rubber coating 49 helps to insure that expensive shot guns or rifles will not be marred by metal contact of the “S” shaped fitting 45 .
[0018] Referring to FIG. 2 , a fishing rod holder assembly 51 includes the same lower section 23 previously described. An upper section 53 of fishing rod holder assembly 51 is seen. Upper section 53 includes an upper tube 55 . Again, the lower end of upper tube 55 is seen as having a smaller diameter than and is fitted into the lower tube 25 . It is equally possible to have the lower end of upper tube 55 to have a larger diameter than and be over fitted onto the lower tube 25 . At the top of the upper tube 55 , a wire loop 61 preferably made of material having a smaller diameter than the upper tube 55 is shown. Where the upper tube may be around five eighths of an inch in diameter, the metal rod of the wire loop may be about three eighths of an inch in diameter metal rod, which has been discovered to work well. The wire loop 61 has a specialized shape to enable it to support the end of a fishing rod which is shown in dashed line format as fishing rod handle 63 . The wire loop 61 has a rear downward curving section 65 and a forward upward curving section 67 . The rear downward curving section 65 and forward upward curving section 67 are joined by a pair of parallel extending connector portions 69 and 71 . Thus, portions 69 , 71 , 67 and 65 form the loop 61 , perhaps with some small increment of upper tube 55 . The attachment of the loop 61 can be in any manner, and as is shown, the two ends of the loop 61 blend into the upper tube 55 closely adjacent but in a way which some what obscures the end points. The manner of attachment of the loop 61 to upper tube 55 may start with an open loop whose ends (not shown because they are blended into the upper tube 55 ) may be welded to the upper tube 55 , with some of the weld solder used to close the end of tube 55 , perhaps partially with some small length of the wire making up the formed loop 61 .
[0019] Generally the curving section 65 is in a vertical plane and forward upward curving section 67 is at an angle with respect to a plane of the curving section 65 or a plane of the pair of parallel extending connector portions 69 and 71 . The curvature of the forward upward curving section 67 is more open to accommodate wider structures which might be at a more forward end of a fishing rod handle 63 .
[0020] Referring to FIG. 3 , the shotgun/rifle rest assembly 21 is illustrated with a rifle 91 and a shotgun 93 leaning into the an “S” shaped fitting 45 . As can be seen, shotgun/rifle rest assembly 21 is shown having been inserted into the ground. Both the rifle 91 and shotgun 93 are stably supported and within easy reach when needed.
[0021] Referring to FIG. 4 , a kit 101 includes the upper section 41 , upper section 54 and the lower section 23 , as a combined deployable and stowable shotgun/rifle rest and fishing rod support set or kit.. Also seen for the first time is an aperture 105 in the lower tube 25 into which a spring urged button 107 seen on the lower end of upper tube 43 of an upper section 41 of shotgun/rifle rest assembly 21 , and also on the lower end of the upper tube 55 of upper section 53 of a fishing rod holder assembly 51 .
[0022] While the present system has been described in terms of a structural kit which provides some common structure to which is attachable alternative structures not expected to be utilized simultaneously in order to maximize utilization of the common structure, one skilled in the art will realize that the structure and techniques of the present system can be applied to many structures which utilize this attribute, including those not shown.
[0023] Although the invention has been derived with reference to particular illustrative embodiments thereof, many changes and modifications of the invention may become apparent to those skilled in the art without departing from the spirit and scope of the invention. Therefore, included within the patent warranted hereon are all such changes and modifications as may reasonably and properly be included within the scope of this contribution to the art.
|
A deployable stowable shotgun/rifle rest & fishing rod holder includes a common lower section which may preferably be hollow tubular construction and having a pinched tip for resistance to any deformation upon being inserted into the soil, and two upper sections which are not expected to be simultaneously needed, one section for a shotgun/rifle rest and one section for a fishing rod support, enables greater utilization of the common lower section.
| 0
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/927,396, filed Jan. 14, 2014, entitled “Portable Spa Construction,” the contents of which is hereby incorporated herein by reference herein in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] The subject disclosure relates to spas, tubs, and the like and more particularly to an improved portable spa structure and the construction thereof.
[0004] 2. Related Art
[0005] Portable spas have become quite popular as a result of their ease of use and multiplicity of features such as varied jet and seating configurations.
SUMMARY
[0006] The following is a summary of description of illustrative embodiments of a new spa structure, and more particularly a new portable spa structure. It is provided as a preface to assist those skilled in the art to more rapidly assimilate the detailed design discussion which ensues and is not intended in any way to limit the scope of the claims which are appended hereto in order to particularly point out the invention.
[0007] According to an illustrative embodiment, a spa structure is provided comprising a plurality of corner pieces, each positioned at a respective corner of the structure and a plurality of trapezoidal shaped side panels positioned between the corner pieces. Each side panel is positioned with its respective side edges located in grooves defined by the corner pieces and their mounting brackets such that each side panel may move or slide both horizontally and vertically with respect to the corner pieces and other structural parts so as to accommodate expansion or contraction of the side panels. In this configuration, a lower edge of each side panel is held in place by a plurality of panel clips, each of which is pivotable into and out of a panel retaining position, which facilitates panel installation and disassembly.
[0008] Such an illustrative structure may further include a generally rectangular base pan of smaller width and length than a generally rectangular outer upper rim of the spa, with the base pan being centrally positioned within and beneath the outer upper rim and including a plurality of downwardly and inwardly swept back lower side surfaces extending from the lower edges of the side panels to lower edges of the base pan. A plurality of vertical support members are configured to support an upper rim of a spa shell, and a plurality of angled force transfer members are attached at respective lower ends of the vertical support members to transfer force from each respective vertical support member to an inner bottom surface of the base pan.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of a portable spa according to an illustrative embodiment;
[0010] FIG. 2 is a perspective view illustrating the internal structure of the spa of FIG. 1 ;
[0011] FIG. 3 is an inverted perspective view of illustrative frame structure of the spa of FIG. 1 ;
[0012] FIG. 4 is an inverted perspective view of the spa of FIG. 1 with side panels removed;
[0013] FIG. 5 is a perspective view illustrating a bottom pan component of the spa of FIG. 1 ;
[0014] FIG. 6 is a perspective fragmentary view illustrating internal support members of the spa of FIG. 1 according to an illustrative embodiment;
[0015] FIG. 7 is a perspective view illustrating assembly of angled force transfer member components according to an illustrative embodiment;
[0016] FIG. 8 is a top perspective view of an illustrative angled force transfer member;
[0017] FIG. 9 is a side perspective view of respective halves of an angled force transfer member according to an illustrative embodiment;
[0018] FIG. 10 is a side view illustrating internal structure of a first half of the illustrative angled force transfer member;
[0019] FIG. 11 is a side view illustrating internal structure of a second half of the illustrative angled force transfer member;
[0020] FIG. 12 is a first side view of the assembled angled force transfer member;
[0021] FIG. 13 is a second side view of the assembled angled force transfer member;
[0022] FIG. 14 is a front view of the assembled angled force transfer member;
[0023] FIG. 15 is a back view of the assembled angled force transfer member;
[0024] FIG. 16 is a fragmentary perspective view illustrating a corner portion of the spa of FIG. 1 ;
[0025] FIG. 17 is a fragmentary front view of the corner portion of FIG. 17 ;
[0026] FIG. 18 is a fragmentary side perspective view of the spa of FIG. 1 with a side panel removed;
[0027] FIG. 19 is a perspective view of an illustrative embodiment of a panel clip in an “open” position;
[0028] FIG. 20 is a perspective view of the panel clip of FIG. 19 in an “closed” position;
[0029] FIG. 21 is a side view of a latch component of the panel clip of FIG. 19 ;
[0030] FIG. 22 is a front view of a latch component of FIG. 21 ;
[0031] FIG. 23 is a rear perspective view of a pivot component of the panel clip of FIG. 19 ;
[0032] FIG. 24 is a front perspective view of the pivot component of FIG. 23 ;
[0033] FIG. 25 is a rear view of the panel clip of FIG. 19 ;
[0034] FIG. 26 is a rear view of the panel clip of FIG. 25 wherein the latch component has moved to the right in the Figure;
[0035] FIG. 27 is a top view of the panel clip of FIGS. 25 and 26 in the “open” position;
[0036] FIG. 28 is a fragmentary perspective view of the panel clip in a “closed” position;
[0037] FIG. 29 is a second fragmentary view of the panel clip of FIG. 28 ;
[0038] FIG. 30 is a front schematic view illustrating installation of a side panel according to an illustrative embodiment; and
[0039] FIG. 31 is a front schematic view illustrating the side panel of FIG. 30 in the installed position.
DETAILED DESCRIPTION
[0040] FIG. 1 illustrates a portable spa 11 having a spa shell 13 , side panels, e.g., 15 , 17 and tapered corner fascia pieces, e.g., 19 , 21 , 23 . The spa shell 11 has a generally rectangular rim 12 about its upper periphery and includes various features such as jets, e.g. 25 , 27 , a filter compartment 29 and a remote control 31 . As may be seen, the lower edges 33 of the side panels 15 , 17 do not extend to the bottom edges 35 of the corner pieces 19 , 21 , 23 but rather terminate at a distance “d” ( FIG. 2 ) above the slab, deck, ground or other surface 30 on which the spa rests, such distance “d” being, for example, 6 inches in one embodiment. In the illustrative embodiment, the corner pieces, e.g., 19 , 21 , 23 , are slightly spaced above, and do not contact, the surface 30 . Additionally, as shown in FIGS. 30 and 31 , the side panels 15 , 17 are trapezoidal in shape in one illustrative embodiment.
[0041] The spa 11 further includes a base pan 39 shown in FIGS. 2 , 4 , and 5 . As may be seen, the lower peripheral side surfaces 37 of the base pan 39 are recessed inwardly or swept back from the side panel edges 33 to provide a pedestal effect, giving the appearance that the spa 11 contacts the floor 35 only at its four corners and at the recessed edge 36 of the base pan 39 . The spa base pan 39 itself has four corners 40 , each of which lies within and is concealed by a respective corner fascia piece, e.g. 19 , 21 , 23 . As seen in FIG. 4 , the bottom of the base pan 39 further includes a grid work of rectangular areas 41 which include recessed fins or “thermal separators” 43 . The grid work is defined by perpendicularly disposed ribs 45 , 47 , whose flat bottom surfaces also rest on the surface 30 . The rib and thermal separator structure on the bottom of the base pan 39 minimizes the surface area of the base pan 39 which is in contact with the surface 30 and, hence, reduces heat transfer from the spa 11 to the surface 30 . In one embodiment, a wavelike shape is imparted to the ribs, assisting in the minimizing the contact area.
[0042] As shown in FIGS. 2 and 3 , in order to support the spa shell 13 , vertical support members 51 are provided to which are attached angled force transfer members 53 , for example, by gluing, snap-fitting, or other fastening mechanism. FIG. 6 particularly shows the interfitting relationship of the base pan side surface 37 and the force transfer members 53 according to an illustrative embodiment. As may be seen, the side surface 37 has an inner horizontally disposed top step 42 and a horizontally disposed lower step 44 . The angled force transfer member 53 includes a stepped edge 46 shaped to mate with the step 42 . The stepped edge 46 forms into an angled surface 48 , which rests on the swept back surface 37 . The angled surface 48 continues into a second step 43 , which mates with the lower step 44 . A slot or channel 50 is further formed in the base pan 39 and snugly receives a foot portion 34 of the angled force transfer member 53 . Mating surfaces of the base pan surface 37 and the force transfer member 53 may be glued, snap-fitted, or otherwise fastened together in position in various embodiments.
[0043] In one embodiment, the vertical support member 51 and the angled force transfer member 53 may be fabricated of extruded ABS plastic and injection molded ABS plastic, respectively. The base pan 39 may be a thermoformed ABS plastic sheet. Other materials and fabrication techniques may of course be used in other embodiments.
[0044] In one embodiment, the force transfer member 53 may be a two piece component comprising respective halves 131 , 133 , as shown in FIGS. 7 to 15 . The halves 131 , 133 , are mated together utilizing two tabs 141 , 143 , formed on the first half 131 and two tabs 150 , 151 formed on the second half 133 . These tabs 141 , 143 ; 150 , 151 may be seen in FIGS. 11 and 10 , respectively.
[0045] As further shown in FIG. 10 , the interior 137 of the first half 131 may have height markers, e.g. “29”, “33”, “36”, “38” molded or formed therein or applied thereto and located adjacent respective slots 139 a , 139 b , 139 c , and 139 d to indicate the particular spa rim height which can be accommodated by utilizing a particular slot. In operation, the two tabs 150 , 151 on half 133 (e.g. FIG. 10 ) slide into one of the four groove pairs 135 a , 134 a ; 135 b , 134 b ; 135 c , 134 c ; 135 d , 134 d , of the respective outer side surfaces of the first half 131 to select a particular height, while the tabs 141 , 143 enter into a pair of holes or apertures 147 , 149 ( FIG. 9 ) of the second half 133 . Thus, the first half 131 can be telescoped between positions -38-, -36-, -33-, -28- to increase or decrease the length of the angled force transfer member 53 and can be locked in position by the tabs 150 , 151 , as further described below.
[0046] The manner in which the first and second halves 131 , 133 are attached together is further illustrated in FIG. 7 . As may be seen, the tab 150 is riding in the second groove 135 c . The tab 151 is also riding in a generally parallel groove 134 c on the opposite side of the first half 131 . At the same time, the tabs 141 , 143 of the first half are passing through grooves 139 b , 140 b ( FIG. 10 ) of the second half 133 , thereby selecting the height of -33- inches. When the tabs 150 , 151 , reach the end of the respective grooves 135 c , 134 c , they snap down over the side surface 136 of the component 131 , e.g., as shown in FIG. 12 , to hold the respective halves 131 , 133 together. At the same time, the tabs 141 , 143 enter a pair of the slots 147 , 149 , as illustrated in FIG. 12 , to further hold the assembly together. It may be noted that FIGS. 12 and 13 illustrate the -28- inch assembly position, whereas the assembly shown in FIG. 7 would result in tabs 150 , 151 being positioned one groove up ( 135 c , 134 c ) and the tabs 141 , 143 being positioned one slot down from the positions shown in FIGS. 12 and 13 .
[0047] As shown in FIGS. 10 and 11 , for example, the first half 131 has a tongue 171 and a cavity 174 formed in its interior, and the second half 133 has a cavity 172 and a tongue 173 formed in its interior. When the first and second halves 131 , 133 are mated together, the tongue 171 on the interior of the first half 131 fits into the cavity 172 in the second half 133 , while the tongue 173 of the second half 133 fits into the cavity 174 formed in the first half 131 . The first half 131 further has an open or “cut-out” area 162 of rectangular cross-section formed therein ( FIG. 7 ). In one embodiment, the area 162 has a shape identical to that of area 161 ( FIG. 9 ). Additional open or hollow areas, e.g., 164 and area 165 ( FIG. 8 ), are formed in the components 131 , 133 to capture foam sprayed into the interior of the spa shell to thereby create a rigid foam/plastic structure.
[0048] As shown in FIG. 8 , the illustrative angle force transfer member 53 has an upper receptacle of generally rectangular cross-section formed as a part thereof having a rectangular rim 47 and a hollow interior 143 . First and second u-shaped projections 201 , 202 are formed in the hollow interior 143 . In one embodiment, the lower end of a vertical support member 51 is configured to snugly mate or snap fit with the structure of the receptacle 141 .
[0049] The illustrative embodiment is further constructed such that each side panel 33 may be slid into position and retained in place without abutting or being attached to the corner pieces 19 , 21 , 23 or other spa structure. For this purpose, corner piece groove structures 65 are provided as shown in FIGS. 16 and 17 , and three panel clips 69 are positioned along a lower surface 72 of the base pan 39 , as shown in FIG. 18 . While three panel clips 69 are shown in FIG. 18 , the number of clips could be one, two, or more in various embodiments.
[0050] FIG. 16 illustrates attachment of one of the tapered corner pieces 19 to respective vertical support members 51 using a number of “U”-shaped brackets 105 . A first leg of each bracket 105 attaches to the support member 51 and a second leg attaches to the corner piece 19 . The length “L” of the first leg of each bracket 105 increases as the edge 107 of the corner piece 19 tapers away downwardly. In one embodiment, the angle θ ( FIG. 17 ) between the corner piece's tapered edge 107 and the vertical is an acute angle, for example, such as six or seven degrees. The increasing bracket length effectively defines a gap or groove 65 between the brackets 105 and the corner piece 19 which lies along the dashed line 109 , effectively paralleling the tapered outside edge 107 . In the illustrative embodiment, the same type of groove 65 is formed by U-shaped brackets 105 associated with each of the other three corner pieces, e.g., 21 , 23 .
[0051] The structure and operation of the panel clips 69 is further illustrated in FIGS. 19-27 . Each panel clip 69 includes a pivot component 73 ( FIGS. 23 , 24 ) and a latch component 75 ( FIGS. 21 , 22 ). The latch component 75 has a hook-shaped back 79 , which is unitarily formed with a front portion 80 having first and second lips 81 , 83 , whose inner surfaces define a channel 85 . The hook-shaped back 79 includes a slot 87 and an elongated opening 89 .
[0052] As shown in FIGS. 23 and 24 , the pivot component 73 has an arcuate back surface 78 from which project two bosses 120 through which are formed respective holes 77 . As illustrated in FIGS. 28 and 29 , respective screws or other fasteners 82 are inserted through the holes and into a side surface 72 of the molded base pan 39 . The bosses 120 cause the arcuate back surface 78 to be spaced apart from the side surface 72 such that the hook shaped back 79 of the pivot component 73 can be slid into the latch component 75 . Thereafter, the latch component 75 may be pivoted from the open position shown in FIG. 19 to the locked position shown in FIGS. 20 , 28 , and 29 in which the channel 85 is oriented vertically so as to retain and prevent downward movement of the bottom edge of a panel 33 while allowing the panel 33 to move laterally.
[0053] FIGS. 25-27 illustrate the operation of the panel clips 69 in more detail. FIG. 25 is a back view of the clip 69 in the locked position of, e.g., FIGS. 20 and 28 . In this position, the right boss 120 of the pivot component 73 extends through the opening 89 , and the left boss 120 extends through the slot 87 . Hence, the latch component 75 cannot pivot due to the abutment of the bosses 120 with the respective adjacent surfaces of the opening 89 and the slot 87 . In this position, in an illustrative embodiment, the screws 82 have further been tightened down to hold the components 73 , 75 in the locked position.
[0054] FIG. 26 is also a back view of the clip 69 , but in this case, the screws 82 have been unloosened slightly, and the latch component 75 has been moved to the right such that the left boss 120 has moved out of the slot 87 , and the right boss 120 has moved into position over a cut-out area 123 formed in the latch component 75 . In such position, the latch component 75 is free to pivot with respect to the pivot component 73 .
[0055] FIG. 27 is a top view of the clip 69 after the pivot component 75 has been pivoted to the unlocked position of FIG. 19 . In this position, the right boss 120 has pivoted into the cut out area 123 of the latch component 75 , and the left boss 120 lies adjacent an outer leg 124 of the latch component 75 .
[0056] The structure thus far described facilitates a side panel mounting method illustrated in FIGS. 30 and 31 . As shown in FIG. 30 , the spa 11 is positioned or raised off the mounting surface 30 . A trapezoidal side panel 33 is then inserted upwardly such that its upper corners and its sides slide into the grooves 65 defined by brackets 105 and the corner pieces 19 , 21 . The panel 33 is then slid further upwardly until its top edge 102 passes behind the rim 12 . At that point, the panel clips 69 are each moved into the locked position shown in FIGS. 20 , 28 , and 29 and the screws 82 are tightened to locking position.
[0057] The just-described side panel mounting method has the advantage that the side panels 33 are not rigidly attached to the corner pieces e.g. 15 , 17 , 19 or other structure, and therefore the panels 33 may expand and contract with temperature variations without the exertion of forces which would distort or otherwise damage the panels 33 if they were not free to expand or contract vertically or horizontally. This method has particular advantages in certain embodiments where the corner pieces, e.g., 17 , are made of plastic and the side panels 33 are constructed of wood or of a plastic which has a coefficient of expansion which is different than that of the corner piece plastic. In such embodiments, the side panels 33 may expand or contract as much as half-inch in very hot or cold conditions, which would likely damage the spa structure, for example, by warping or cracking the panels 33 .
[0058] Those skilled in the art will appreciate that various adaptations and modifications of the just described preferred embodiment can be configured without departing from the scope and spirit of the invention. Therefore, it is to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.
|
Spa side panels are trapezoidally-shaped and mounted in respective grooves defined by adjacent tapered corner pieces and their mounting brackets to accommodate differences in coefficients of expansion of the respective parts and prevent structural damage. Angled force transfer members are configured to mate with swept back side surfaces of a spa base pan to achieve a pedestal appearance, and the bottom surface of the base pan is constructed to reduce heat transfer to the spa support surface.
| 0
|
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method for manufacturing a mold of a light guide plate, and more particularly, to a method for manufacturing a mold of a light guide plate with a plurality of microstructures thereon.
[0003] 2. Description of the Prior Art
[0004] Backlight units are known in the art. The backlight module, which is a key element in the liquid crystal displays (LCDs), is widely used in monitors, notebooks, digital cameras, projectors and so on. The light guide plate is one of the important parts of the backlight module. The light guide plate is capable of guiding light emitted from a light source so as to transform a point light source or a linear light source into a planar light source.
[0005] The methods of manufacturing the light guide plates are typically divided into two major categories: printing process and non-printing process. The non-printing process has advantages of stable quality, high precision, and so on, and is a mainstream manufacturing method of the light guide plates in the market. The non-printing process is to form patterns on a mold first and to manufacture the light guide plates by the mold with an injection molding process.
[0006] The methods of manufacturing the mold of the light guide plates are typically divided into two major categories. One is forming patterns on the mold directly with an etching process. The other is forming patterns on the mold with a semiconducting process, such as a photolithography process. For example, U.S. Pat. No. 5,776,636 discloses related technology. Please refer to FIG. 1 to FIG. 6 which are diagrams of manufacturing a mold of a light guide plate in the prior art. As shown in FIG. 1 , a photoresist layer 11 is spread upon a substrate 10 first. The substrate 10 can be a glass substrate. As shown in FIG. 2 and FIG. 3 , a photomask 12 with specified pattern thereon is utilized for forming a photoresist pattern on the substrate 10 with exposing and developing processes. As shown in FIG. 4 , a metal layer 13 is plated upon the photoresist pattern with a sputtering process or an evaporation process. As shown in FIG. 5 , a metal plate 14 is electroformed on the metal layer 13 . As shown in FIG. 6 , the metal layer 13 is separated from the photoresist layer 11 and the substrate 10 so as to generate a mold 15 with a pattern on the surface corresponding to the photoresist pattern.
[0007] However the conventional method of manufacturing the mold of the light guide plates has disadvantages as follows. A height of the pattern on the mold depends on a thickness of the photoresist layer 11 , which causes difficulty in controlling the height of the pattern on the mold. In addition, the pattern on the mold is limited due to a small range of the thickness of the photoresist layer 11 . Furthermore, the pattern on the mold is formed with exposing and developing processes so that microstructures or complicated structures can not be formed on the pattern.
SUMMARY OF THE INVENTION
[0008] It is therefore a primary objective of the claimed invention to provide a method for manufacturing a mold of a light guide plate with a plurality of microstructures thereon for solving the above-mentioned problem.
[0009] According to the claimed invention, a method for manufacturing a mold of a light guide plate includes following steps: providing a substrate and forming a plurality of microstructures on the substrate; depositing a first metal layer upon the substrate; spreading a photoresist layer on the first metal layer, exposing the photoresist layer to a photomask, and developing a photoresist pattern; removing a part of the first metal layer without cover of the photoresist pattern so as to form a sink pattern; depositing a second metal layer upon the sink pattern; electroforming a metal plate on the second metal layer; and remaining the metal plate and the second metal layer by separating the metal plate from the photoresist layer, the first metal layer, and the substrate so as to generate the mold of the light guide plate.
[0010] Other objectives, features and advantages of the present invention will be further understood from the further technology features disclosed by the present invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 to FIG. 6 are diagrams of manufacturing a mold of a light guide plate in the prior art.
[0012] FIG. 7 is a flowchart of manufacturing a mold of a light guide plate according to a preferred embodiment of the present invention.
[0013] FIG. 8 to FIG. 15 are diagrams of manufacturing the mold of the light guide plate according to the preferred embodiment of the present invention.
DETAILED DESCRIPTION
[0014] 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 embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” etc., is used with reference to the orientation of the Figure(s) being described. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. On the other hand, the drawings are only schematic and the sizes of components may be exaggerated for clarity. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. Similarly, the terms “facing,” “faces” and variations thereof herein are used broadly and encompass direct and indirect facing, and “adjacent to” and variations thereof herein are used broadly and encompass directly and indirectly “adjacent to”. Therefore, the description of “A” component facing “B” component herein may contain the situations that “A” component facing “B” component directly or one or more additional components is between “A” component and “B” component. Also, the description of “A” component “adjacent to” “B” component herein may contain the situations that “A” component is directly “adjacent to” “B” component or one or more additional components is between “A” component and “B” component. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.
[0015] Please refer to FIG. 7 to FIG. 15 . FIG. 7 is a flowchart of manufacturing a mold of a light guide plate according to a preferred embodiment of the present invention. FIG. 8 to FIG. 15 are diagrams of manufacturing the mold of the light guide plate according to the preferred embodiment of the present invention. The method of the present invention includes following steps:
[0016] Step 100 : provide a substrate 20 and form a plurality of microstructures 201 on the substrate 20 .
[0017] Step 102 : deposit a first metal layer 21 upon the substrate 20 .
[0018] Step 104 : spread a photoresist layer 22 on the first metal layer 21 , expose the photoresist layer 22 to a photomask 30 , and develop a photoresist pattern 23 .
[0019] Step 106 : remove a part of the first metal layer 21 without cover of the photoresist pattern 23 so as to form a sink pattern 24 .
[0020] Step 108 : deposit a second metal layer 25 upon the sink pattern 24 .
[0021] Step 110 : electroform a metal plate 26 on the second metal layer 25 .
[0022] Step 112 : remain the metal plate 26 and the second metal layer 25 by separating the metal plate 26 from the photoresist layer 22 , the first metal layer 21 , and the substrate 20 so as to generate a mold 27 of the light guide plate.
[0023] The detailed description of above-mentioned steps is introduced as follows. As shown in FIG. 8 , the substrate 20 is provided, and the plurality of microstructures 201 is formed on the substrate 20 . The substrate 20 is made of, for example, metal material, such as stainless steel. The plurality of microstructures 201 on the substrate 20 are carved on the metal substrate with, for example, a micro-drill, a laser process, a mold process, or other mechanical process. The microstructure 201 is, for example, a semicircular microstructure, a trapezoid microstructure, a V-grooved microstructure, and so on.
[0024] As shown in FIG. 9 , the first metal layer 21 is deposited upon the substrate 20 . For example, the first metal layer 21 is electroplated upon the substrate 20 . A thickness of the first metal layer 21 has to be greater than a height of the microstructure 201 . The first metal layer 21 is made of, for example, nickel, copper, and so on.
[0025] As shown in FIG. 10 and FIG. 11 , the photoresist layer 22 is spread on the first metal layer 21 . Then the photoresist layer 22 is exposed to the photomask 30 , and the photoresist pattern 23 is developed. The thickness of the first metal layer 21 has to be greater than the height of the microstructure 201 so that the photoresist layer 22 is spread on the first metal layer 21 uniformly for preventing the un-uniform photoresist pattern 23 .
[0026] As shown in FIG. 12 , a part of the first metal layer 21 without cover of the photoresist pattern 23 is removed so as to form the sink pattern 24 . The part of the first metal layer 21 without cover of the photoresist pattern 23 is etched chemically so as to form the sink pattern 24 . Therefore, some of the microstructures 201 are exposed. As shown in FIG. 13 , the second metal layer 25 is deposited upon the sink pattern 24 . The second metal layer 25 is deposited upon the sink pattern 24 with, for example, a sputtering process or a chemical coating process. The second metal layer 25 is made of, for example, cladding metal material, such as nickel or copper. The second metal layer 25 forms as an electroforming conductive layer.
[0027] As shown in FIG. 14 and FIG. 15 , the metal plate 26 is electroformed on the second metal layer 25 . Then the metal plate 26 and the second metal layer 2 are remained, that is, the second metal layer 25 and the metal plate 26 are separated from the photoresist layer 22 , the first metal layer 21 , and the substrate 20 so as to generate the mold 27 of the light guide plate. The light guide plate with microstructures is generated with the mold 27 by an injection molding process.
[0028] In contrast to the prior art, the method for manufacturing the mold of the light guide plate according to the present invention has advantages that the height of the pattern on the mold does not depend on the thickness of the photoresist layer. Therefore, microstructures or complicated structures can be formed on the mold for manufacturing the light guide plate with corresponding microstructures or complicated structures.
[0029] The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the invention and its best mode practical application, thereby to enable persons skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the invention”, “the present invention” or the like is not necessary limited the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the invention does not imply a limitation on the invention, and no such limitation is to be inferred. The invention is limited only by the spirit and scope of the appended claims. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from this disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the invention. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the present invention as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.
|
A method for manufacturing a mold of a light guide plate is disclosed. The method includes following steps: providing a substrate and forming a plurality of microstructures on the substrate; depositing a first metal layer upon the substrate; spreading a photoresist layer on the first metal layer, exposing the photoresist layer to a photomask, and developing a photoresist pattern; removing a part of the first metal layer without cover of the photoresist pattern so as to form a sink pattern; depositing a second metal layer upon the sink pattern; electroforming a metal plate on the second metal layer; and remaining the metal plate and the second metal layer by separating the metal plate from the photoresist layer, the first metal layer, and the substrate so as to generate the mold of the light guide plate.
| 6
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/236,787, filed Sep. 6, 2002, entitled: “Synthetic Ripple Regulator,” by M. Walters et al (hereinafter referred to as the '787 patent application), assigned to the assignee of the present application and the disclosure of which is incorporated herein.
FIELD OF THE INVENTION
[0002] The present invention relates in general to power supply circuits and components therefor, and is particularly directed to an arrangement for synchronizing a plurality of synthetic ripple generators that generate artificial or synthesized ripple waveforms to control switching operations of a multiphase DC-DC converter.
BACKGROUND OF THE INVENTION
[0003] As described in the background section of the above-referenced '787 patent application, electrical power for integrated circuits is typically supplied by one or more direct current (DC) power sources. In a number of applications the circuit may require plural regulated voltages that are different from the available supply voltage, which may be relatively low e.g., on the order of three volts or less, particularly where low current consumption is desirable, such as in portable, battery-powered devices. (This architecture may achieve a much high voltage difference in portable applications, for example an input voltage on the order of 4.5-25V and an output voltage Vo on the order of 0.5V-3.7V.) Moreover, in many applications the load current may vary over several orders of magnitude. To address these requirements it has been common practice to employ ripple generator-based converters, such as a hysteresis or ‘bang-bang’ converter of the type shown in FIG. 1.
[0004] Such a ripple regulator-based DC-DC voltage converter employs a relatively simple control mechanism and provides a fast response to a load transient. The switching frequency of the ripple voltage regulator is asynchronous, which is advantageous in applications where direct control of the switching frequency or the switching edges is desired. For this purpose, the ripple voltage regulator of FIG. 1 employs a hysteresis comparator 10 , that switchably controls a gate drive circuit 20 , respective output drive ports 22 and 23 of which are coupled to the control or gate drive inputs of a pair of electronic power switching devices, respectively shown as an upper P-MOSFET (or PFET) device 30 and a lower N-MOSFET (or NFET) device 40 . These FET switching devices have their drain-source paths coupled in series between first and second reference voltages (Vdd and ground (GND)).
[0005] The gate drive circuit 20 controllably switches or turns the two switching devices 30 and 40 on and off, in accordance with a pulse width modulation (PWM) switching waveform (such as that shown at PWM in the timing diagram of FIG. 2) supplied by comparator 10 . The upper PFET device 30 is turned on and off by an upper gate switching signal UG applied by the gate driver 20 to the gate of the PFET device 20 , and the lower NFET device 30 is turned on and off by a lower gate switching signal LG applied by the gate driver 20 to the gate of the NFET device 30 .
[0006] A common or phase voltage node 35 between the two power FETs 30 / 40 is coupled through an inductor 50 to a capacitor 60 , which is referenced to a prescribed potential (e.g., ground (GND)). The connection 55 between the inductor 50 and the capacitor 60 serves as an output node, from which an output voltage Vout (shown as triangular waveform Output in FIG. 2) is derived. In order to regulate the output voltage relative to a prescribed reference voltage, the output node 55 is coupled to a first, inverting (−) input 11 of the hysteresis comparator 10 , a second, non-inverting (+) input 12 of which is coupled to receive a DC Reference voltage.
[0007] In such a hysteretic regulator, the output PWM signal waveform produced by hysteresis comparator 10 transitions to a first state (e.g., goes high) when the output voltage Vout at node 55 falls below the reference voltage Reference (minus the comparator's inherent hysteresis voltage Δ). Conversely, the comparator's PWM output transitions to a second state (e.g., goes low) when the output voltage Vout exceeds the reference voltage plus the hysteresis voltage Δ. The application of or increase in load will cause the output voltage (Vout) to decrease below the reference voltage, in response to which comparator 10 triggers the gate drive to turn on the upper switching device 30 . Because the converter is asynchronous, the gate drive control signal does not wait for a synchronizing clock, as is common in most fixed frequency PWM control schemes.
[0008] Principal concerns with this type of ripple voltage regulator include large ripple voltage, DC voltage accuracy, and switching frequency. Since the hysteretic comparator 10 directly sets the magnitude of the ripple voltage Vout, employing a smaller hysteresis Δ will reduce the power conversion efficiency, as switching frequency increases with smaller hysteresis. In order to control the DC output voltage, which is a function of the ripple wave shape, the peak 71 and the valley 72 of the output ripple voltage (Output, shown in FIG. 2) is regulated. For the triangular wave shape shown, the DC value of the output voltage is a function of the PWM duty factor. The output voltage wave shape also changes at light loads, when current through the inductor 50 becomes discontinuous, producing relatively short ‘spikes’ between which are relatively long periods of low voltage, as shown by the DISCON waveshape in FIG. 2. Since the ripple voltage wave shape varies with input line and load conditions, maintaining tight DC regulation is difficult.
[0009] In addition, improvements in capacitor technology will change the ripple wave shape. In particular, the current state of ceramic capacitor technology has enabled the equivalent series resistance or ESR (which produces the piecewise linear or triangular wave shape of the output voltage waveform shown in FIG. 2) of ceramic capacitors to be reduced to very low values. At very low values of ESR, however, the output voltage's ripple shape changes from triangular to a non-linear shape (e.g., parabolic and sinusoidal). This causes the output voltage to overshoot the hysteretic threshold, and results in higher peak-to-peak ripple. As a result, the very improvements that were intended to lower the output voltage ripple in DC-DC converters can actually cause increased ripple when used in a ripple voltage regulator.
[0010] In accordance with the invention disclosed in the '787 application, shortcomings of conventional ripple voltage regulators, including those described above, are effectively obviated by the synthetic ripple voltage regulator shown in FIG. 3. This synthetic ripple voltage regulator generates an auxiliary voltage waveform, that effectively replicates or mirrors the waveform ripple current through the output inductor 50 , and uses this auxiliary voltage waveform to control toggling of the hysteretic comparator 10 . Using such a reconstructed current for the purpose of ripple voltage regulation results in low output ripple and simplified compensation.
[0011] More particularly, the synthetic ripple voltage regulator of FIG. 3 employs a transconductance amplifier 110 , the output of which is coupled to a ‘ripple voltage’ capacitor 120 . The transconductance amplifier 110 produces an output current I RAMP proportional to the voltage across inductor 50 , which is interconnected between a node 35 common with the upper and lower MOSFETs (respective gate drives 21 and 22 for which are produced by a gate drive circuit 20 ), and an output node 55 . The ripple voltage capacitor 120 transforms this output current ramp into an inductor current-representative voltage having the desired waveform shape. A benefit of synthesizing the ripple waveform based on inductor current is the inherent feed-forward characteristic. For a step input voltage change, the current I RAMP produced by the transconductance amplifier 110 will change proportionally to modify the conduction interval of the power switching devices.
[0012] For this purpose, transconductance amplifier 110 has a first, non-inverting (+) input 111 coupled to the phase node 35 and a second, inverting (−) input 112 coupled to output voltage node 55 at the other end of inductor 50 , so that the transconductance amplifier 110 effectively ‘sees’ the voltage across inductor 50 . The output voltage node 55 is further coupled to a first terminal 121 of capacitor 120 and to the inverting (−) input 141 of an error amplifier 130 inserted upstream of the hysteresis comparator 10 . Error amplifier 130 serves to increase the DC regulation accuracy, providing high DC gain to reduce errors due to ripple wave shape, various offsets, and other errors. Error amplifier 130 has a second, non-inverting (+) input 132 thereof coupled to receive the voltage Reference, while its output 133 is coupled to the non-inverting (+) input 12 of hysteresis comparator 10 . In the configuration of FIG. 3, the output of the error amplifier 130 follows the load current. The transconductance amplifier 110 has its output 113 coupled to a second terminal 122 of the capacitor 120 and to inverting (−) input 11 of the hysteresis comparator 10 .
[0013] The operation of the synthetic ripple voltage regulator of FIG. 3 may be understood with reference to the set of waveform timing diagrams of FIG. 4. As a non-limiting example, the regulator voltage may be set at a value of Reference=1 VDC and the hysteresis comparator 10 may trip with +/−100 mV of hysteresis. The inductance of inductor 50 is 1 μH and the output capacitance is 10 μF. The line M 1 (at the 30 μsec time mark) in FIG. 4 represents a change in input voltage from a value on the order of 3.6 VDC prior to M 1 to a value on the order of 4.2 VDC at M 1 and thereafter.
[0014] The upper waveform 501 corresponds to the ripple voltage generated across the ripple voltage capacitor 120 ; the middle waveform 502 is the current through inductor 50 , and the lower waveform 503 is the output voltage at node 55 . The similarity of the respective ripple and inductor current waveforms 501 and 502 is readily apparent, as shown by respective step transitions 511 / 521 and 512 / 522 therein, at t=20 μs and t=50 μs. As shown by waveform 502 , the converter is initially supplying an inductor current on the order 100 mA for an input supply voltage of 3.6 VDC. This inductor current is discontinuous and the switching frequency has a relatively stable value on the order of 900 kHz.
[0015] At the transient 521 (t=20 μs) in waveform 502 , there is a stepwise (X10) increase in the load current from 100 mA to a value on the order of 1 A, and the switching frequency increases to a frequency on the order of 1.5 MHz. From the output voltage waveform 503 , it can be seen that the amount of ripple 531 occurring at this transient is relatively small (on the order of only +/−3 mV, which is well below that (+/−100 mV) of the prior art regulator of FIG. 1, during discontinuous operation, where load current=100 mA, and then drops to +/−1.5 mV).
[0016] At the M 1 or t=30 μs time mark, there is a stepwise increase in input voltage from 3.6 VDC to 4.2 VDC, and the switching frequency increases to almost 2.3 MHz, yet the levels of each of waveforms 501 , 502 and 503 remain stable. Subsequently, at t=50 μs, there is a step transient 512 in the inductor/load current waveform 501 , which drops back down from 1 A to 100 mA, and the switching frequency settles to a value on the order of 1.3 MHz. As can be seen in the output voltage waveform 503 , like the ripple 531 occurring at the t=20 μs transient, the amount of ripple 532 for this further transient is also relatively small (on the order of only +−3 mV and dropping to +/−1.5 mV), so that the output voltage may be effectively regulated at a value on the order of the voltage Reference of 1 VDC.
SUMMARY OF THE INVENTION
[0017] In accordance with the present invention, the functionality of the transconductance amplifier and hysteretic comparator architecture disclosed in the '787 application is applied to a multiphase DC-DC voltage generator, to realize a new and improved circuit arrangement for synchronizing a plurality of synthetic ripple voltage generators, that generate artificial or synthesized ripple voltage waveforms for controlling switching operations of a multiphase DC-DC voltage converter. The synthetic ripple voltage regulator of the invention has a variable frequency that is a function of the input voltage, output voltage and load.
[0018] For this purpose, the invention comprises a master hysteretic comparator that is referenced to upper and lower voltage thresholds. The master hysteretic comparator monitors a master ripple voltage waveform that is produced across a capacitor by a current proportional to the difference between the output voltage and either the input voltage or a reference voltage (ground). The proportionality current is produced by a transconductance amplifier pair. The output of the master hysteretic comparator serves as a master clock signal that is sequentially coupled to PWM latches, the states of which define the durations of respective components of the synthesized ripple voltage. A respective PWM latch has a first state thereof initiated by a selected master clock signal produced by the hysteretic comparator and terminated by an associated comparator that monitors a respective phase node voltage.
[0019] As noted above, the synthetic ripple voltage regulator of the invention has a variable frequency that is a function of the input voltage, output voltage and load. In accordance with an alternative approach, a comparator and one-shot are used to generated a master clock signal having a fixed, steady-state frequency, with the difference between Vlower and Vupper being set proportional to the output voltage Vo. In an alternative methodology for producing produce the output signal PWM1, the output signal from the sequence logic causes the output port signal PWM1 to change state (e.g., go high), and a switch is turned on. The ripple capacitor voltage across a ripple capacitor is thereby increased by a charge current proportional to (Vin−Vo). The phase1 ripple voltage crosses the upper voltage threshold Vupper, and a comparator resets the output flip-flop from which PWM1 is produced. This causes the PWM1 output to change state (go low). During the interval between opposite peaks in the phase1 ripple capacitor voltage, the voltage across the capacitor decreases by a discharge current proportional to Vo.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] [0020]FIG. 1 diagrammatically illustrates the general architecture of a conventional ripple regulator-based DC-DC voltage converter;
[0021] [0021]FIG. 2 is a timing diagram showing PWM and output voltage waveforms associated with the operation of the ripple regulator-based DC-DC voltage converter of FIG. 1;
[0022] [0022]FIG. 3 diagrammatically illustrates an implementation of the synthetic ripple voltage regulator in accordance with the invention disclosed in the '787 application;
[0023] [0023]FIG. 4 is a timing diagram showing waveforms associated with the operation of the synthetic ripple voltage regulator of FIG. 3;
[0024] [0024]FIG. 5 diagrammatically illustrates a multiphase synthetic ripple voltage regulator in accordance with the present invention;
[0025] [0025]FIG. 6 contains a set of timing diagrams associated with the operation of the multiphase synthetic ripple voltage regulator of FIG. 5.
[0026] [0026]FIG. 7 shows the use of a single comparator and one-shot to generate a master clock signal;
[0027] [0027]FIG. 8 is a timing diagram associated with the operation of FIG. 7;
[0028] [0028]FIG. 9 illustrates an alternative circuit arrangement for producing an output signal PWM1;
[0029] [0029]FIG. 10 is a timing diagram associated with the operation of FIG. 8;
[0030] [0030]FIG. 11 is a timing diagram of upper and lower voltages associated with a load step;
[0031] [0031]FIG. 12 shows a master clock pulse train associated with the transient increase of FIG. 11; and
[0032] [0032]FIG. 13 graphically illustrates the change in frequency between a first relatively steady state, followed by a transition to a higher frequency and then a return to a further steady state frequency.
DETAILED DESCRIPTION
[0033] Before describing a non-limiting, but preferred embodiment of the multiphase synthetic ripple voltage regulator synchronization scheme of the present invention, it should be observed that the invention resides primarily in an arrangement of conventional circuit components, and the manner in which they may be incorporated into a multiphase hysteretic controller of the type described above. It is to be understood that the invention may be embodied in a variety of other implementations, and should not be construed as being limited to only the embodiment shown and described herein. Rather, the implementation example shown and described here is intended to supply only those specifics that are pertinent to the present invention, so as not to obscure the disclosure with details that are readily apparent to one skilled in the art having the benefit of present description. Throughout the text and drawings like numbers refer to like parts.
[0034] Attention is now directed to FIG. 5, which diagrammatically illustrates the general architecture of a multiphase synthetic ripple voltage regulator in accordance the present invention for a two phase regulator. It will be readily appreciated from the description to follow that the architecture and functionality of the present invention may be readily expanded to additional phases as desired. A two phase implementation has been shown as a reduced complexity multiphase example for purposes of reducing the complexity of the drawings and their attendant description.
[0035] The multiphase synthetic ripple voltage regulator of FIG. 5 is shown as comprising a ‘master’ hysteretic comparator 200 formed of upper and lower threshold comparators 210 and 220 , outputs of which are respectively coupled to the SET and RESET inputs of a SET/RESET flip-flop 230 . A first, inverting (−) input 211 of comparator 210 is coupled to receive an upper threshold voltage Vupper, while first, non-inverting (+) input 221 of comparator 220 is coupled to receive a lower threshold voltage Vlower, that is some prescribed offset ΔV/2 lower than the upper threshold voltage Vupper. Each of the second, non-inverting input 212 of comparator 210 and the second, inverting (−) input 222 of comparator 220 are coupled to a common terminal 241 of a controlled switch 240 , and also to a capacitor 245 , which is referenced to ground. Switch 240 is controlled by the Q output of flip-flop 230 .
[0036] A first input terminal 242 of switch 240 is coupled to the output of a transconductance amplifier 250 , while a second input terminal 243 of switch 240 is coupled to the output of a transconductance amplifier 260 . Transconductance amplifier 250 has a first, non-inverting (+) input 251 coupled to receive the input voltage Vin to the regulator, while a second, inverting (−) input 252 thereof is coupled to receive the output voltage Vo of the regulator (namely, the voltage at output node 55 of the circuits of FIGS. 1 and 3, for example). Transconductance amplifier 250 produces an output current proportional to the difference between its inputs, namely proportional to Vin−Vo. Transconductance amplifier 260 has a first, non-inverting (+) input 261 coupled to ground, while a second input 262 thereof is coupled to receive the output voltage Vo. Transconductance amplifier 250 produces an output current proportional to the difference between its inputs, namely proportional to 0−Vo.
[0037] The QBAR output of flip-flop 230 is coupled to a sequence logic circuit 270 . Sequence logic circuit 270 , which may be implemented as a counter, has N outputs corresponding to the number of phases being generated. In the present two phase example, sequence logic circuit 270 has a first output 271 coupled to the SET input of a SET/RESET flip-flop 280 and a second output 272 coupled to the SET input of SET/RESET flip-flop 290 . For this purpose, sequence logic 270 may be implemented as a flip-flop for a two-phase application, or a shift register in more than a two-phase application. The RESET input of flip-flop 280 is coupled to the output of a comparator 300 , while the RESET input of flip-flop 290 is coupled to the output of a comparator 310 .
[0038] Comparators 300 and 310 have first, non-inverting (+) inputs 301 and 311 respectively coupled to receive the upper threshold voltage Vupper. The inverting (−) input 302 of comparator 300 is coupled to receive a phase 1 ripple voltage waveform that is developed across a capacitor 305 , as a result of current supplied to capacitor 305 by a phase 1 transconductance amplifier 320 . The inverting (−) input 312 of comparator 310 is coupled to receive a phase 2 ripple voltage that is developed across a capacitor 315 , as a result of current supplied to capacitor 315 by a phase 2 transconductance amplifier 330 .
[0039] Phase 1 transconductance amplifier 320 has a first, non-inverting (+) input 321 coupled to receive a phase 1 voltage Vphase1 and a second, inverting (−) input 322 coupled to receive the output voltage Vo. The phase 1 voltage Vphase1 corresponds to the voltage at node 35 of the converter circuit associated with a first phase output voltage, and controllably gated in accordance with the PWM1 waveform output of output flip-flop 280 . Thus, transconductance amplifier 320 generates a voltage Phase1 ripple proportional to Vphase1−Vo. Similarly, phase 2 transconductance amplifier 330 has a first, non-inverting (+) input 331 coupled to receive a phase 2 voltage Vphase2, and a second, inverting (−) input 332 coupled to receive the output voltage Vo. The phase 2 voltage Vphase2 corresponds to the voltage at node 35 of the converter circuit associated with a second phase output voltage, and controllably gated in accordance with the PWM2 output of output flip-flop 290 . Thus, transconductance amplifier 330 generates a voltage Phase2 ripple proportional to Vphase2−Vo.
[0040] Operation of the multi-phase synthetic ripple voltage regulator of the present invention may be readily understood with reference to the timing diagrams of FIG. 6. The uppermost portion of FIG. 6 shows a master ripple waveform 400 , which exhibits a sawtooth behavior with respect to the upper and lower thresholds Vupper and Vlower, respectively. The middle portion of FIG. 6 shows phase1 and phase2 ripple waveforms, which exhibit a sawtooth behavior with respect to the upper threshold Vupper. It is to be noted that the two instances of the Vupper threshold are in actuality at the same level. However, they have been separated in FIG. 6 in order to facilitate an illustration of the various ripple waveforms and, in particular, the times of occurrence of various events for those waveforms. This avoids a superimposed cluttering of the phase1 and phase 2 waveforms by the master ripple waveform. Finally, the lowermost portion of FIG. 6 shows a master clock (clk) signal that is produced at the QBAR output of flip-flop 230 , and the PWM1 and PWM2 waveforms produced at the Q outputs of output flip-flops 280 and 290 , respectively.
[0041] Considering initially, the master ripple and the master clock waveforms, at time t0, the master ripple waveform is shown as decreasing and crossing the lower threshold Vlower. During the interval leading up to t0, the common terminal 241 of switch 240 is connected to input terminal 243 , so that a current proportional to ground (0V)−Vo, or simply −Vo is applied to capacitor 245 . Namely, the voltage V 245 across capacitor, which is the master ripple voltage, is decreasing during this interval. When (at time t0) this decreasing voltage crosses the lower threshold Vlower which is applied to the input 221 of comparator 220 , comparator 220 is tripped and resets flip-flop 230 . The latency between the actual crossing of the lower threshold Vlower and time t1 when flip-flop 230 resets (its QBAR output goes high) is due to second order circuit effects. When the QBAR output of flip-flop 230 goes high, the master clock (Master clk) goes high, and sequence logic 270 couples this output to the set input of the PWM1 output flip-flop 280 , so that its Q output 281 (which represents the PWM1 waveform) goes high at time t1.
[0042] The change in state in the QBAR output of flip-flop 230 switches the connection of switch 240 to input 242 , so that the output of transconductance amplifier 250 is monitored by the hysteretic comparator circuitry. During a time interval beginning with t1, transconductance amplifier 250 produces an output current that is proportional to the difference between its inputs, namely proportional to Vin−Vo. This current is applied to capacitor 245 , so that as capacitor 245 is charged, its voltage (Master ripple) increases, as shown between time t1 and t2. Eventually, the increase in the master ripple voltage will exceed the upper threshold Vupper, causing comparator 210 to trip and set flip-flop 230 . It may be again noted that due to second order latency effects, the time t2 associated with the resetting of flip-flop 230 is slightly delayed relative to the actual instant at which the master ripple voltage crosses the upper threshold voltage Vupper.
[0043] With flip-flop 230 now set, its QBAR output goes low at time t2, and remains there until it is again reset by comparator 220 , as described above. During the interval subsequent to time t2, with flip-flop 230 being set, switch 240 connects input 243 to its common terminal 241 , so that a negative current proportional to −Vo is again supplied to capacitor 245 by transconductance amplifier 260 , causing the master ripple voltage across capacitor 245 to decrease, as shown by the negative slope of the master ripple waveform. Eventually, at time t4, the master ripple waveform again crosses the lower threshold Vlower, so that comparator 220 is again tripped and resets flip-flop 230 . When the QBAR output of flip-flop 230 goes high, sequence logic 270 couples this output via output port 272 to the set input of the PWM2 output flip-flop 290 , so that its Q output 291 (the PWM2 waveform) goes high at time t4.
[0044] The reset state of flip-flop 230 switches the connection of the common terminal 241 of switch 240 to its input 242 , so that the output of transconductance amplifier 250 is now monitored by the hysteretic comparator circuitry. During a new time interval beginning with time t4, transconductance amplifier 250 produces an output current that is proportional to the difference between its inputs, namely proportional to Vin−Vo. Again, as described above, this current is applied to capacitor 245 , so that capacitor 245 is charged causing its voltage Master ripple to increase, as shown in the interval between times t4 and t5. Eventually, this increase in Master ripple voltage will exceed the upper threshold Vupper, causing comparator 210 to trip, setting flip-flop 230 .
[0045] With flip-flop 230 again set, its QBAR output goes low at time t5, and remains there until it is once again reset by comparator 220 , as described above. During the interval subsequent to time t5, with flip-flop 230 set, switch 240 reconnects input 243 to its common terminal 241 , so that a negative current is again supplied to capacitor 245 by the transconductance amplifier 260 , causing the master ripple voltage across capacitor 245 to decrease, as shown by the negative slope of the master ripple waveform during the time interval t5-t7. Eventually, at time t7, the master ripple waveform crosses the lower threshold Vlower, so that comparator 220 is again tripped and resets flip-flop 230 . When the QBAR output of flip-flop 230 again goes high, sequence logic 270 recouples this output via output port 271 back to the set input of the PWM1 output flip-flop 280 , so that its Q output 281 (and thereby the PWM1 waveform) goes high at time t7. This above process is repeated for subsequent cycles, as shown.
[0046] Although the master ripple generator portion of the circuit directly controls the generation of the master clock and the rising edges of the PWM1 and PWM2 waveforms, its does not directly control the falling edges of the PWM1 and PWM2 waveforms. The falling edges are controlled by the phase1 and phase 2 ripple waveforms, as will described below. It should be noted, however, that the master ripple generator serves to control the frequency of the master clock and thereby the ripple voltages, since its generation is dependent upon the input and output voltages. Increasing the input voltage Vin increases the magnitude of the current (Vin−Vo) supplied by transconductance amplifier 250 to capacitor 245 , and thereby reduces the time required for the master ripple voltage across capacitor 245 to reach the upper threshold voltage Vupper. Conversely, decreasing the output voltage Vo not only increases the magnitude of the current (Vin−Vo) supplied by transconductance amplifier 250 , but increases the magnitude of the negative current supplied by transconductance amplifier 260 , the latter being effective to reduce the time required for the master ripple voltage across capacitor 245 to reach the lower threshold voltage Vlower.
[0047] As pointed out above, transconductance amplifiers 320 and 330 produce output currents Phase1 ripple and Phase2 ripple that are respectively proportional to Vphase1−Vo and Vphase2−Vo, with the voltages Vphase1 and Vphase2 corresponding to the voltages at nodes 35 of the converter circuits associated with respective phases of the multiphase DC-DC converter. Considering first the Phase1 ripple waveform, the phase1 ripple waveform is shown as decreasing and the waveform continues to decrease until the master ripple voltage crosses the lower threshold, at time t0, so that comparator 220 is tripped and resets flip-flop 230 . As described above, due to second order latency effects, flip-flop 230 is reset at time t1, at which time sequence logic 270 drives the set input of the PWM1 output flip-flop 280 , so that its Q output 281 and thereby the PWM1 waveform goes high. With the PWM1 waveform going high, the Vphase1 voltage at node 35 of its associated DC-DC converter is driven high, so that transconductance amplifier 320 begins to charge capacitor 305 with a current proportional to Vphase1−Vo, whereby the voltage across capacitor 305 increases, as shown by the positive slope portion of the phase1 ripple voltage beginning at time t1. Eventually, this increasing phase1 ripple voltage, which is applied to the inverting (−) input 302 of comparator 300 crosses the upper threshold voltage Vupper, which is applied to the non-inverting input 301 of comparator 300 . When this happens, and taking into account second order latency effects, comparator 300 is tripped at time t3, and therefore drives the reset input of PWM1 output flip-flop 280 . With flip-flop 280 being reset by comparator 300 at time t3, the Q output 281 of flip-flop 280 is now driven low, causing the PWM1 waveform to go low. The PWM1 waveform will remain low until flip-flop 280 is again set at time t7 as described above. During the interval from t3 to t7, the relatively low phase1 voltage derived from phase node 35 causes transconductance amplifier 320 to apply a negative current (on the order of −Vo) to capacitor 305 , so that the phase1 ripple voltage waveform is continuously decreasing until the next cycle for PWM1.
[0048] The Phase2 ripple waveform operates in the same manner as the Phase1 waveform, described above, except that it is every other master clock cycle relative to the Phase1 waveform. Namely, just prior to time t4, the phase2 ripple waveform is decreasing and the phase2 ripple waveform continues to decrease until the master ripple voltage crosses the lower threshold, so that comparator 220 is tripped and resets flip-flop 230 . As described above, due to second order latency effects, flip-flop 230 is reset at time t4, at which time sequence logic 270 drives the set input of the PWM2 output flip-flop 290 , so that its Q output 291 and thereby the PWM2 waveform goes high. With the PWM2 waveform going high, the Vphase2 voltage at node 35 of its associated DC-DC converter is driven high, so that transconductance amplifier 330 begins to charge capacitor 315 with a current proportional to Vphase2−Vo, which increases the voltage across capacitor 315 , as shown by the positive slope portion of the phase2 ripple voltage beginning at time t4. Eventually, this increasing phase2 ripple voltage, which is applied to the inverting (−) input 312 of comparator 310 crosses the upper threshold voltage Vupper, which is applied to the non-inverting input 311 of comparator 310 . When this happens, and taking into account second order latency effects, comparator 310 is tripped at time t5, and therefore drives the reset input of PWM2 output flip-flop 290 . With flip-flop 290 being reset by comparator 310 at time t5, the Q output 291 of flip-flop 290 is now driven low, causing the PWM2 waveform to go low. The PWM2 waveform will remain low until flip-flop 290 is eventually again set by the next alternating cycle of the master clock, subsequent to that occurring between t7 and t8. During the next interval beginning with time t6, the relatively low phase2 voltage derived from the phase node 35 causes transconductance amplifier 330 to apply a negative current (on the order of −Vo) to capacitor 315 , so that the phase2 ripple voltage waveform is continuously decreasing until the next cycle for PWM2.
[0049] In accordance with a first alternative approach, the master ripple waveform produced across capacitor 245 may be created by a discharge and reset technique, using a single comparator as shown in FIG. 7, and the associated timing diagram of FIG. 8. At a time to, capacitor C 245 is discharged by a current proportional to Vo. When the voltage across capacitor C 245 drops below or crosses the threshold Vlower at t1, the output of comparator 80 and a one-shot 82 , shown as MSLCK, close the switch and reset the voltage across capacitor C 245 to the value of the upper voltage rail Vupper during the interval from t3 to t4. It should also be noted that a pair of master ripple capacitors may be employed in the place of the signal master capacitor C 245 . In this case the two capacitors alternately discharge from Vupper to Vlower, which serves to eliminate the reset interval (from t3 to t4).
[0050] [0050]FIGS. 9 and 10 diagrammatically illustrate an alternative technique to produce the output signal PWM1. This same circuit may be applied to any of the other phases in a multiphase application. At time t0 in the timing diagram of FIG. 9, the signal CLK 1 ( 271 ) from the sequence logic causes the output port (PWM1) of flip-flop 280 to go high, and a switch 350 is turned on. The ripple capacitor voltage across capacitor C RIP increases by a charge current that is proportional to (Vin−Vo). At time t1, the phase1 ripple voltage crosses the upper voltage threshold Vupper, and the comparator RRCMP resets flip-flop 280 , causing the PWM1 output to change state (go low). During the interval from t1-t2, the voltage across capacitor C RIP decreases by a discharge current proportional to Vo.
[0051] A beneficial feature of the present invention, particularly in connection with multiphase systems, is the fact that it varies the converter's switching frequency in response to load changes, something which the prior art does not do. In contrast, the prior art hysteretic converter of FIG. 1, described above, actually slows down the switching frequency during a load step (increase). This load step causes a depressed output voltage, which has the effect of turning on the high side or upper FET 30 , and leaves that FET on, until the output voltage at node 55 increases to the upper hysteretic set point, shown at 71 in FIG. 2. This means that such a control method is problematic in a multiphase system, where a single converter channel must pick up the full load current unit it can drive the output voltage above the upper hysteretic set point. As a consequence, a full load transient applied to a multiphase converter (such as a three-phase converter) results in one power channel having to deliver three times its steady state power.
[0052] In accordance with the present invention, this problem is obviated by increasing the converter's switching frequency in response to a load step. This may be understood with reference to the block diagrams of FIGS. 3 and 5, described above, and the timing diagrams of FIGS. 11, 12 and 13 . In particular, for a load step (increase), the voltage at the output node 55 will initially decrease, which is fed back to input 131 of the error amplifier 130 . This decrease in the voltage at error amplifier 131 creates a larger differential across the error amplifier input and therefore a higher Vupper value produced at its output 133 . This transitional increase in the value of Vupper applied to input 211 of amplifier 210 in FIG. 5 (and that of its associated voltage value Vlower applied to the input 221 of amplifier 220 ) is shown in FIG. 11. As can be seen therein, the master ripple will now encounter the Vupper and Vlower references more frequently, so that the Q output of flip-flop 230 will produce a master clock more frequently, as shown in FIG. 12. FIG. 13 graphically illustrates the change in frequency between a first relatively steady state having a frequency on the order of 289 KHz, followed by a transition (during the transient state) to a frequency on the order of 560 KHz which, in turn, is followed by a further steady state frequency on the order of 300 KHz.
[0053] It may be noted that the master clock signal initiates the PWM pulse which turns on the upper FET of the next successive power channel of the multiphase system, with the next power channel being selected by the sequence logic 270 . Increasing the switching frequency means each successive power channel will pick up the load sooner than it does during steady state, so that all of the power channels participate in picking up a power of the transient load current.
[0054] An additional advantage of this method results for transient load steps that are less than full load. This may be contrasted with having to synchronize all of the power channels to turn-on the upper FET in each power channel in response to a load transient. With a less than full load transient, the resulting voltage is likely to overshoot the target regulation voltage. The present invention provides a relative smooth response to any magnitude transient.
[0055] As will be appreciated from the foregoing description, by applying functionality of the transconductance amplifier and hysteretic comparator architecture disclosed in the above-referenced '787 application to a multiphase DC-DC voltage generator, the present invention is able to realize a new and improved circuit arrangement for synchronizing a plurality of synthetic ripple voltage generators, that generate artificial or synthesized ripple voltage waveforms for controlling switching operations of a multiphase DC-DC voltage converter.
[0056] While we have shown and described an embodiment in accordance with the present invention, it is to be understood that the same is not limited thereto but is susceptible to numerous changes and modifications as known to a person skilled in the art, and we therefore do not wish to be limited to the details shown and described herein, but intend to cover all such changes and modifications as are obvious to one of ordinary skill in the art.
|
A multiphase ripple voltage regulator generator employs a hysteretic comparator referenced to upper and lower voltage thresholds. The hysteretic comparator monitors a master ripple voltage waveform developed across a capacitor supplied with a current proportional to the difference between the output voltage and either the input voltage or ground. The output of the hysteretic comparator generates a master clock signal that is sequentially coupled to PWM latches, the states of which define the durations of respective components of the synthesized ripple voltage. A respective PWM latch has a first state initiated by a selected master clock signal and terminated by an associated phase voltage comparator that monitors a respective phase node voltage.
| 7
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119(e) to provisional patent application Ser. No. 61/062,396 filed Jan. 25, 2008, the disclosure of which is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
BACKGROUND OF THE INVENTION
[0003] The U.S. health care system is by far the most technologically advanced among the industrialized nations and continues to provide world leadership in areas such as pharmaceuticals and life support technology. If the health care system is currently in crisis, it is not for want of ideas but rather for want of financial discipline.
[0004] A central problem in the health care system is the misalignment in financial motivations of the two main players: the insurance companies and the medical establishment. Therefore, one solution to this problem is to realign these two incentives. Medical insurance companies have two main functions: underwriting and claim payments on the one hand, and investment on the other. On the underwriting side, agents and accountants process the corresponding claims paperwork. On the investment side, cash reserves are invested with minimal real knowledge of the inner workings of the insurance industry by the investors. Typically, little or no communication is made between underwriters and investors.
[0005] The divide between underwriters and investors is difficult to bridge without a way to funnel excess liquidity from the investment department to finance the receivables in inventory with the claims payment department. Such a funnel can be created in the form of short-term securities created from medical-receivable backed securities. The solution then, is to redistribute some of the excess liquidity at insurance companies to doctors, hospitals, and other medical service providers (collectively “medical service providers”) by bundling the claims originated by the medical service providers into “medical-backed securities” and selling them to the insurance companies liable to pay these very claims. The present invention is directed to a framework for implementing such a solution.
[0006] U.S. Pat. No. 7,254,555 to Field (“Field”) purports to disclose a computerized system to allow healthcare providers to “sell” their medical claims as asset-backed commercial paper (ABCP) through conventional ABCP conduits. More specifically, Field generates data on historical collection experience of the healthcare provider's claims. These data include a net collectible value matrix that provides the number of claims actually paid by individual payers, e.g., patients and medical insurance companies, and a time-to-payment histogram. The system further tracks pools of claims using statistical data that includes net collectible value matrix, which includes the number of claims paid and the standard deviation of this percentage; and a collection histogram for payment timing from the billing date of the service.
[0007] The Field patent, however, does not provide a vehicle for the securitization of individual and pooled claims nor does the Field system provide real-time re-evaluation of the value of individual claims, e.g., using valuation feedback. Securitization refers to pooling or packaging an expected future cash flow into securities that can be sold to investors for a lump sum payment or timed lump sum payments. Advantageously, especially with lending institutions or other regulated institutions that must maintain a capital reserve, use of ABCP conduits can reduce those reserves.
[0008] The Field system also is static in that advance rates of the ABCP are not changed in real-time to reflect the most recent historical data of the individual claims and the medical service provider. Instead, Field relies on third-party rating agencies to estimate value. For example, Field teaches using an 18 to 24 month collection period before updates. In today's fast moving securities industry, when the average life of a medical claim is approximately 45 days, waiting for 18 or 24 months is unacceptable.
[0009] Accordingly, it would be desirable to provide a dynamic securitization system for high-volume claims, such as medical service claims, that valuates and re-valuates individual claims in real-time, to update contemporaneously and continuously the bankable value, e.g., the primary advance rate, of the individual claim. It would also be desirable to provide a securitization system that obviates using third-party rating agencies. It would further be desirable to provide a securitization system that enables lending institutions and other regulated institutions to reduce capital reserves and free-up more capital for investment elsewhere.
SUMMARY OF THE INVENTION
[0010] Methods for expediting payment of claims to medical service providers and for reducing bank capital reserve requirements are disclosed. The methods include evaluating a risk of full payment of each medical claim; grouping a plurality of individual claims from a medical service provider(s) based on a commonality of risk; generating a security representative of the risk of the grouped claims and an investment value of the security; and exchanging a pre-payment amount to the medical service provider(s) for the security. More specifically, evaluating the risk of full payment includes comparing individual medical claims to a database of historical performance of the medical service provider(s) and of similar medical claims and, moreover, evaluating the risk of full payment includes evaluating for each individual claim an expected payment amount and an expected time of payment by an obligor(s). The method further includes providing a supplemental payment amount(s) to the medical service provider(s) after payment by the obligor(s).
[0011] A claims statistical valuation engine is also disclosed. The valuation engine includes a database(s) containing data on high-volume, e.g., medical, claim histories; means for generating an advance payment value relating to an expected future payment amount and an expected payment time for each individual claim based on said data; means for synthesizing similar or substantially similar advance payment values into plural pools of individual, high-volume claims; and means for generating a claim-backed security having a primary advance rate for sale to an investor.
[0012] A system program that is embodied on a computer readable medium and executable on a computer processor is disclosed. The program is adapted to execute the method described above and to control the valuation engine described above.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0013] The invention will be more fully understood by reference to the following detailed description of the invention in conjunction with the drawings, of which:
[0014] FIG. 1 illustrates the operation of a monetary performance incentive method according to an embodiment of the present invention; and
[0015] FIG. 2 illustrates a flow chart of a health care securitization method according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The present invention introduces a monetary performance incentive for doctors, hospitals, and other medical service providers (collectively “medical service providers”) to deliver medical services at cost effective levels. Although the invention will be described in terms of medical service claims and the medical service industry, the invention is not to be construed as being limited thereto. Specifically, the present invention applies to any industry characterized by a high-volume of individual claims whose promises of future payment or cash flow can be the subject of securitization.
[0017] Moreover, although the invention will be described in connection with a bank lending scenarios, the invention is not to be construed as being limited thereto as there are a host of institutional and private lenders to whom the securities offered for sale in accordance with the present invention would interest.
[0018] In the traditional operation of the relationship between obligors, e.g., patients, medical insurance companies, Medicare/Medicaid, and the like, and medical service providers, a service provider submits a claim under a patient's insurance policy for reimbursement for the non co-pay or non-deductible portion of the patient's service costs. Processing and acceptance by the obligor could take weeks to months to process and only then does the service provider receive payment from the obligor. When the obligor's payment and the co-pay do not equal the provider's service costs, the provider then must bill the patient for the balance. This time- and labor-intensive process increases provider overhead, and, therefore, service costs, and provides no incentive to file correct claims. Correct claims include, without limitation, those claims that are expressly covered by the patient's insurance carrier in contrast to “incorrect” claims that are expressly not covered.
[0019] According to the invention and referring to FIG. 1 , individual claims coming in from a service provider(s) are pooled into a group(s) for which the risk of full payment can be evaluated based on several factors including past history. The use of the World Wide Web, e.g., the Internet, for forwarding the data related to individual claims from service providers to a valuation engine is expressly envisioned. The valuation engine can be disposed with the obligor, e.g., the patient's medical insurance company, or with a third party, e.g., a claim-processing firm.
[0020] Using any of well known algorithms, the valuation engine assesses the investment value of the pooled claims using a database(s) of historical performances of the corresponding providers' claims. With this information the financial department of the insurer (or the third party) produces securities, e.g., asset-backed commercial paper (ABCP), that represent that estimated value. Advantageously, the pooled claims undergo securitization.
[0021] The insurer (or third party) exchanges these securities for a lump sum, discounted valued amount, effectively prepaying all or some portion of the claim at a pre-determined and agreed upon discount for which the insurer (or third party) receives the security and its accompanying promise of future payment(s). The terms of the security agreement include, in exchange for prepayment of the claimed amount, certain contractual provisions that are necessary for securitization, chief of which is that the pooled claims are subject to a lien. Thus, the claims serve as collateral for investors.
[0022] For example, the insurer (or third party) can file financial statements under a local Uniform Commercial Code, e.g., UCC-1, to record a lien on the securities. Such liens can be filed for the entire nominal amount of the pooled claims, subject to reformation and removal. Only a portion of the nominal claim amount, however, is expected to be reimbursed.
[0023] This serves several functions. First, it provides the service provider with more rapid, e.g., immediate, partial payment, before the claims are evaluated by the insurer. The extent of the partial payment—if any at all—is based on historical data on similar individual claims associated with the respective service provider. Secondly, once the insurer completes the claim evaluation, subsequent payment(s) is made to the investor or, in some instances, to a trustee. Subsequent payments may include a surplus or a deficit. Any surplus is distributed and any deficit is assessed among the participants, which include the investors, the service providers, and any third parties. The investment is, then, terminated and the security essentially expires. Individual security liens placed on the claims are subsequently modified or removed once the claims are, respectively, partially or fully adjudicated.
[0024] The details of operation of this system are shown in FIG. 1 . A description of the applicable theory and mathematics involved, from which an algorithm, application, driver program, and the like can be derived, follows.
[0025] A major competitive advantage of the present invention is its ability to create statistically uniform pools of high-volume claims, e.g., medical claims, on a real-time basis. By this, we mean that each pool includes a heterogeneously distributed set of claims from various sellers (or other third parties) and is required to have homogeneous statistical properties if it is going to be eligible for securitization inside a commercial paper conduit or a liquidity-backed exchange (LBE) expecting uniform risk.
[0026] Once assembled, the securities or liabilities backed by such pools can be made available to primary market investors, e.g., using a Web-enabled interface, at a discount rate that has been pre-determined, e.g., using an auction process similar to which happens, for example, with student-loan asset-backed securities (ABS).
[0027] In credit markets with liquidity support, the goal is always the same, which is to say: to ensure that the liquidity characteristics of the underlying assets are such as to guarantee on a statistical basis that investors will be reimbursed on time and in full with an extremely high probability, which is usually in the neighborhood of 99%. However, to ensure that high probability reimbursement happens at an affordable cost, the distribution of claim payments, both in the dollar and time domains, needs to be computed as accurately as possible, to allow investors to gauge an amount of external liquidity that might eventually be required. External liquidity may be needed in the event that liquidity properties required of commercial paper or liquidity-backed notes are not generally available in the credit markets on a stand-alone basis. In short, statistical certainty, although highly desirable, is not sufficient because capital markets mandate absolute certainty of full and timely payment(s).
[0028] As a result of the need for absolute certainty, a large financial institution acting as a sponsor, normally labeled a “liquidity bank”, must be available to stand in for the underlying assets should the CP or ABS fail to live up to their original statistical promise. Notwithstanding, it is most definitely not the intention of the liquidity provider to “stand in” on every possible pool. As a result, liquidity banks will typically require that the claim pools be highly liquid on their own.
[0029] To that end, the objective, then, is to assemble pools of high-volume claims, e.g., medical claims, on a first-come, first-serve basis and to issue therefrom the smallest pool possible that simultaneously meets the cash flow requirements imposed by respective liquidity providers.
[0030] A “physical claim” consists of a sequence of logical claims, which we label “sub-claims” to ease the interpretation. Each physical claim, although submitted as a whole, may be paid in whole or in part at various stages at the option of the insurance company. This means that individual service items included in a claim may be reimbursed at various times. In many cases and for a variety of reasons, some individual sub-claims may not be reimbursed at all.
[0031] Despite the fact that the above, disembodied payment mechanics present an obvious cash-flow reconciliation problem that requires expert software systems, from the statistical stand point it creates an opportunity for a more efficient and streamlined financing system. The following nomenclature will be used in the remainder of this document:
[0000]
Parameter
Definition
c
As a superscript, indicates a claim level quantity
sc
As a superscript, indicates a sub-claim level
quantity
P
As a superscript, indicates a pool level quantity.
$
As a subscript, indicates a dollar space quantity
t
As a subscript, indicates a time space quantity
T
Maturity of CP notes for a given pool
N
Number of sub-claims in one physical claim
M
Number of claims in one CP pool
μ
Used anywhere, refers to a mean value
σ
Used anywhere, refers to a standard deviation
E[x]
Refers to the mathematical expectation operator
(defined below)
r
Periodic CP discount rate (capital market quantity)
Σ
The covariance matrix with entries σ ij (defined
below)
x T
Means the transpose of vector or matrix x
ρ
The correlation coefficient in a two-dimensional
correlation matrix
|Σ|
The determinant of matrix Σ
exp(x)
The exponential function of argument x
Σ −1
The inverse of arbitrary matrixΣ
x
Indicates the mean of a quantity, in this case x
ω $ ji sc
Model-derived dollar weight of sub-claim j within
claim i
α ji sc
Billed dollar amount of sub-claim j within claim i
p i c
Nominal dollar amount of claimi
P 0
Nominal dollar amount of an arbitrary pool of
M claims
α
Pool-level amount of allowable maturing CP notes
(the dependent variable)
δ
Default probability of an arbitrary pool of claims
(rating based)
f (x, y)
Two-dimensional Gaussian PDF in time [x] and
dollar [y] space
∥x∥
The Euclidean norm of quantity, vector or matrix x
K
The tolerance for the root-locus procedure (see
below)
π
3.14159 . . . .
g i
Primary advance for claim i
h j
Primary advance for sub-claim j
C k P
Aggregate cash flow to the pool after CP notes
mature
q ki
Secondary, monthly cash flow to claim i at the end
of period k
T c
Maximum pool life, and where we have by definition T c > T
S f P
Pool-level dollar servicing fee (to SMA)
β
Pool calibration factor for computing ρ
D d
CP dealer discount in basis points
s r
SMA servicing fee rate (ca. 50 bps based on P 0 )
[0032] In theory, a mathematical expectation operator, E, for a vector, x, consisting of n elements can be defined as follows:
[0000]
E
[
x
]
=
1
n
∑
i
=
1
n
x
i
.
[0033] A covariance matrix, Σ, with entries σ ij can be defined as follows with respect to the components, x i , of column-vector, x:
[0000] σ ij ≡E [( x i − x i )( x j − x j )].
[0034] In vector notation, the covariance matrix can also be written, for some column-vector, x, as:
[0000] Σ≡ E [( x− x )( x− x )].
[0035] Those of ordinary skill in the art can appreciate that these data are two “dimensions”. The first is a “horizontal” dimension along which expectations will be measured for any one data element. The second is a “vertical” dimension that distinguishes different data elements. For this discussion, we will consider two data elements: time to reimbursement (in days) and reimbursement amount (in $US).
[0036] The pool issuing the CP note(s) consists of a set of physical, individual claims provided by medical service providers. Each pool can be assembled “on the run”, which is to say, in real-time, as a different aggregate dollar-amount of medical claims. These pools will evidence a wide ranging universe of claim characteristics in terms of amount, expected payment delay, originating hospital, and so forth. The underwriting criteria arising from any single securitized pool will thus form the basis of a payment distribution forecast. This forecast will need to take place once the market reaches critical mass.
[0037] The disclosed algorithm is predicated on the existence of a real-time claim valuation model. Without this model, the statistical parameters needed to assemble uniform pools of claims will not be available when needed. Thus, in the following description, we assume that such a model is available at all times.
Claim Characteristics
[0038] A physical claim, consisting either of a physical piece of paper or, alternatively, of an electronic file stored on a hard drive, a computer disk, and the like, can be regarded as a sequence of N items, e.g., services, procedures, laboratory tests, and so forth. Each such item is defined as a sub-claim and is nominally valued, i.e. billed, at α ji sc . Collectively, the sub-claims from the physical claim add up to a pre-determined, future dollar amount, p i c . Consequently, the following nominal relationship holds at all times between the sub-claim nominal amounts and the aggregate claim nominal amount:
[0000]
p
i
c
=
∑
j
=
1
N
a
ji
sc
EQN
.
1
[0039] Similarly, a pool containing M physical claims can be nominally valued at P 0 with:
[0000]
P
0
=
∑
i
=
1
M
p
i
c
EQN
.
2
[0040] As mentioned above, each claim can be billed and paid in whole or in part, essentially at the whim of the insurance carrier. As a result, sub-claims are typically reimbursed at various points in time and in various dollar amounts, including zero, prescribed by some pre-existing, complex algorithm. These dollar amount are, by definition, unknown at the time the claim is financed. Indeed, the absence of solid, reproducible knowledge on the reimbursement properties of discrete or complex medical claims is one of the problems solved by the present invention.
[0041] With a real-time valuation model, there are four statistical parameters with respect to any claim eligible for financing:
[0000] μ $ ji sc =The mean reimbursement for sub-claim j of claim i;
σ $ ji sc =The standard deviation of reimbursements for sub-claim j of claim i;
μ tji sc =The mean reimbursement delay for sub-claim j of claim i; and
σ tji sc =The standard deviation of reimbursement delays for sub-claim j of claim i.
[0042] In order to synthesize pool-level parameters, it is necessary to aggregate values at the sub-claim level into a claim-level figure that will later be used in computing pool-level quantities. Because sub-claims are originated and paid independently from each other, we may consider them an independent, two-dimensional dataset and may therefore calculate the following four claim-level measures μ $i c , μ ti c , σ $i c and σ ti c the way we normally do in the case of independent random variables, viz.:
[0000]
μ
$
i
c
=
∑
j
=
1
N
μ
$
ji
sc
EQN
.
3
μ
ti
c
=
[
∑
j
=
1
N
μ
tji
sc
μ
$
ji
sc
]
/
μ
$
i
c
EQN
.
4
σ
$
i
c
=
∑
j
=
1
N
(
σ
$
ji
sc
)
2
EQN
.
5
σ
t
i
c
=
∑
j
=
1
N
(
ω
$
ji
sc
σ
tji
sc
)
2
,
ω
$
ji
sc
≡
μ
$
ji
sc
/
μ
$
i
c
.
EQN
.
6
Gaussian Density Function (PDF)
[0043] Having computed the above four claim-level measures, which are required to assemble uniform pools of medical claims, a two-dimensional probability density function (PDF) to serve as the basis of note issuance must be specified. In order to do so, the computation of the same four statistical parameters at the pool level is of paramount importance. This is because in order to compute the note amount that the conduit sponsors can safely issue out of any given pool, it is necessary to derive a probability density function of payment amounts and delays.
[0044] It is assumed that the density function best reflecting empirical reality is Gaussian. Defining x as the dollar-space variable at the pool level and y as the time-space variable at the pool level, the two-dimensional, Gaussian probability density function can be defined as follows. Given that
[0000] z≡[x,y] T ;
[0000] m≡E[z]; and
[0000] Σ=The two-dimensional (2D) covariance matrix.
[0000] We can express the 2D Gaussian PDF in vector notation as follows:
[0000]
f
(
z
)
=
1
2
π
∑
1
/
2
exp
{
-
1
2
(
z
-
m
)
T
∑
-
1
(
z
-
m
)
}
EQN
.
7
[0000] In order to compute the parameters of the covariance matrix, Σ, the following four pool-level statistical measures are needed:
μ $ P =Mean pool-level reimbursement for an arbitrary pool;
σ $ P =Standard deviation of pool-level reimbursements for an arbitrary pool;
μ t P =Mean pool-level delay for an arbitrary pool; and
σ t P =Standard deviation of pool-level delays for an arbitrary pool.
[0045] To ensure “vertical” independence at the pool-level, the following equations for an average reimbursement amount and standard deviation of such amount apply:
[0000]
μ
$
P
=
1
M
∑
i
=
1
M
μ
$
i
c
;
and
EQN
.
8
σ
$
P
=
1
M
∑
i
=
1
M
(
σ
$
i
c
)
2
.
EQN
.
9
[0046] Likewise, in the case of a time delay variable, the mean reimbursement delay for the given pool can be computed using the following standard independent-variable relationships:
[0000]
μ
t
P
=
1
M
∑
i
=
1
M
μ
t
i
c
;
and
EQN
.
10
σ
t
P
=
1
M
∑
i
=
1
M
(
σ
t
i
c
)
2
.
EQN
.
11
[0047] Invoking the central limit theorem, the two-dimensional, joint, i.e., payment amount versus payment delay, distribution will be Gaussian. By strict definition, the central limit theorem is inapplicable because it applies only in one dimension. However, since it is valid at least in one dimension, a Gaussian distribution is more likely to approximate the actual distribution than any other known distribution, save the actual one, which remains unknown a priori. Indeed, the Gaussian distribution represents the least committal density function at our disposal to solve our problem.
[0048] The assumption of independence between claims does not mean that the pool is free from correlation at the “horizontal” level. Particularly, the particular characteristics of a discrete claim will have an impact on its reimbursement delay. In general, we find that, on a weighed-average basis, relatively “expensive” claims tend to be reimbursed later than less expensive ones. As a result, computation of the coefficient ρ, which correlates reimbursement amount and reimbursement delay, is required.
[0049] Recalling the definition of ρ from basic statistics:
[0000]
ρ
≡
σ
$
t
P
σ
$
P
σ
t
P
.
EQN
.
12
[0000] By, further, defining the co-variance between reimbursement amount and reimbursement delay according to the following equation:
[0000] σ $t P =E [( X P −μ $ P )( Y P −μ t P )] EQN. 13,
[0000] in which the “synthetic” parameters are defined as:
X P represents the amount reimbursed on each claim in the pool; and
Y P represents the dollar weighted-average time at which this amount is reimbursed.
The adjective “synthetic” is used because the aggregate amount collected by the pool will come in piecemeal—if at all—as time unfolds.
[0050] In order to compute the coefficient ρ, the co-variance term σ $t P must be estimated. To obtain an accurate estimate, a model of how the claims in the pool will be reimbursed, i.e. at what value and with what delay, is necessary. In practice, this forces one to introduce an estimator for such amounts. The estimator can also be used as a calibrating function should pool-liquidity experience ever fall short of a stated goal. Accordingly, with respect to claim i
[0000] x i c ≈μ $i c −βσ $i c EQN. 14, and
[0000] y i c ≈μ ti c +βσ ti c EQN. 15.
[0051] Variables x i c and y i c in EQNS. 14 and 15, respectively, represent the estimated reimbursement amount and the delay on a given claim. Parameter β in each equation is a calibration parameter aimed at reproducing the anticipated covariant experience within securitized pools. Initially, β=0 but is subject to upward, or even downward, adjustments based on the average liquidity performance of actual pools.
[0052] In theory, if the actual values of standard deviations σ $ P and σ t P are available, the value of β is inconsequential. Unfortunately, this is rarely the case. However, once payment histories of a sufficient number of pools is available, the correlation coefficient ρ can be re-computed automatically and more accurate empirical values can replace estimated values.
[0053] Assuming that all individual claims within a discrete pool are reimbursed at their average value (less some amount based on their estimated dollar variance), and at their average delay (plus some additional delay based on their estimated temporal variance), the sole covariance term σ $t P is calculated as follows:
[0000]
σ
$
t
P
=
1
M
∑
i
=
1
M
(
x
i
c
-
μ
$
P
)
(
y
i
c
-
μ
t
P
)
,
EQN
.
16
[0000] which produces an estimate for ρ, the last missing variable needed as an input to the Gaussian PDF. As long as the payment behavior of relatively more expensive claims is correct, ρ will be a positive number. Otherwise, in instances where this is not accurate, the above mechanics can automatically adjust the density function, allowing for a larger advance than within an equivalent pool where significant covariant behavior can be expected.
[0054] After expanding the vector notation, the functional relationship for a 2D Gaussian PDF, in which x is a mean reimbursement amount and y is a mean reimbursement delay in the pool as a whole, can be expressed using the following equation:
[0000]
f
(
x
,
y
)
=
1
2
π
1
-
ρ
2
σ
$
P
σ
t
P
exp
{
-
1
2
(
1
-
ρ
2
)
[
[
(
x
-
μ
$
P
)
σ
$
P
]
2
-
2
ρ
(
x
-
μ
$
P
)
(
y
-
μ
t
P
)
σ
$
P
σ
t
P
+
[
(
y
-
μ
t
P
)
σ
t
P
]
2
]
}
.
EQN
.
17
Root-Locus Algorithm
[0055] Advantageously, the advance rate for the packaged claims sold in a pool is determined so that only a very small percentage of reimbursement events—in terms of both dollar and time domains—lie outside the norms established for this purpose. For the system to operate properly, periodic collections, i.e., payments by obligors, at least equal to the face amount of the maturing liquidity or CP notes backed by the pool (plus associated fees) within a delay of ninety days or less, i.e. when the notes are designed to mature, are required. This total amount will be slightly more than the advance rate experienced by conduit sellers.
[0056] Designating this situation event as A, the probability, P(A), that event A will occur can be calculated. Hence, use of a note primary-advance rate yields a constant value, which will be near unity for all intents and purposes.
[0057] In practice, if ε is the total average cash amount per claim that should be collected by the expected note maturity date, T, and δ is the allowable default rate based on the rating assigned to the notes, operating criterion can be defined in probabilistic terms by the following equation:
[0000] P ( X>ε,t<T )=1−δ EQN. 18.
[0000] In other words, the face-amount of liquidity notes issued so that the probability of a default on maturing liquidity or CP notes (absent liquidity) should be less than some rating-based threshold. Hence, liquidity providers will not be required to advance funds to the exchange in order to avert an impending default except in rare cases, which, statistically speaking, likely would occur, if at all, only δ percent of the time.
[0058] In the event that actions to avoid default become necessary of liquidity providers, any funds already advanced by the liquidity provider become a lien on future cash flows, accruing to the legal vehicle backed by the claims. The discount nature of liquidity markets, however, makes it impossible to wait until sufficient cash comes in to refund the notes in full at some discount rate, i.e., the notes are conceived in terms of liquidity risk, not credit risk.
[0059] The allowable average issue amount ε is the sum of the advance rate α on the nominal amount P 0 plus fees to others and third parties. Due to discounting, healthcare providers who sell receivables to the pool receive a pro-rated advance payment that is slightly smaller than α. A servicing fee rate s r to others and third parties, who operate the system, is based on the nominal amount of the claims in a given pool, not on the primary advance rate α. For example,
[0000]
S
f
P
=
s
r
P
0
M
.
EQN
.
19
[0000] Hence, the aggregate fee to others and third parties for a given pool would be the amount s r P 0 . Hence, on an average basis:
[0000]
ɛ
=
α
P
0
M
+
S
f
P
EQN
.
20
[0000] It should be noted that, once the two-dimensional density function of reimbursement amounts and delays is available explicitly, e.g., using empirical data, it becomes easier to calculate the required amount of cash from which the advance rate can be derived.
[0060] Indeed, using EQN. 20, a root-locus search algorithm, in which the maturing note advance rate α is computed, can be performed. The maturing advance rate is the advance rate that ensures that operating criteria are met statistically. Remembering that the maximum collectable dollar amount is P 0 , and defining
[0000]
λ
=
P
0
M
,
[0000] the iterated function, G(α), is given by the following equation:
[0000]
G
(
α
)
≡
∫
ɛ
(
α
)
λ
∫
0
T
f
(
x
,
y
)
x
y
-
1
+
δ
EQN
.
21
[0061] To determine the unknown advance rate, α, a standard numerical method that stops iterating when ∥G(α)∥, i.e., the norm of G(α), falls below a given threshold, i.e. when ∥G(α)∥≦K, is used. The value of K is largely arbitrary, but a value in the neighborhood of 1% of δ is usually acceptable.
[0062] Simpson's rule is more than adequate as an integral formula for the solution of the above root-locus problem. In addition, the roots of the appropriate Tchebychev polynomials as the two-dimensional co-location points at which to evaluate the function ƒ(x,y) can be used in lieu of using equally spaced points.
[0063] On a statistical basis, a discrete pool's computed average advance rate will approach the quantity μ $ P . This is due to the fact that, for a given pool, the average reimbursement on the total number of individual claims increases linearly while σ $ P , the variance of reimbursement amounts, increases less rapidly. It follows, then, that, at some point, the aggregate amount of allowable notes will be sufficiently close to the mean reimbursement value as to be practically indistinguishable from such amount. Consequently, pools of sufficient size need to be assembled in real-time so that hospital-sellers can monetize them for an amount sufficiently close to their fair market value, which is generally understood to equal the mean μ $i c . Otherwise, the average advance on a claim may seem too remote from μ $i c to be acceptable to hospitals. The window of acceptability is likely to be in the neighborhood of 5%. Once it is reached, the pool can be “released” and go on to become a primary market instrument, e.g., in the Web-enabled purchase.
Allocations of Cash Flow Receipts to Claim-Holders
[0064] To compute monetary allocations to each investor or claim-holder, an aggregate claim reimbursement amount, m $ P , within a given pool must be determined. This parameter is obtained as follows:
[0000]
m
$
P
=
∑
i
=
1
M
μ
$
i
c
.
EQN
.
22
[0000] However, the upshot of these basic considerations is that the following claim-wise, primary advance allocation ƒ i must be satisfied:
[0000]
f
i
=
(
1
-
D
d
)
α
P
0
(
1
+
r
)
μ
$
i
c
m
$
P
,
i
∈
[
1
,
M
]
.
EQN
.
23
[0000] From EQN. 23, the entire proceeds of note issuance, less the dealer discount, D d , is allocated to the sellers, i.e., the medical service providers, based on their pro rata contribution to the pool. The term αP 0 /(1+r) is, thus, the aggregate price investors or buyers will pay for the securities. For example, at a discount rate of 4.0% APR, a $1000 pool having an estimated future value of $600, is issued, the notes backed by a given pool can be sold to 90-day (¼-year) buyers for a price of approximately $600/(1+0.04/4)=$594.06.
The price amount would then be available for distribution to conduit sellers with respect to this particular pool. Advantageously, lending institutions and other regulated institutions can reduce capital reserves by a similar amount.
[0065] Not only will note discount rates change at least daily according to market supply and demand conditions and other factors, but the quality of the claims found inside a $1,000 pool cannot expect to be uniform for any two pools. Thus, in general, each pool will attract its own advance rate at the time it is sold to investors via the conduit or exchange.
Sub-claim Allocations
[0066] Sub-claim allocations can be computed using the following equation:
[0000]
h
j
=
f
i
μ
$
ji
sc
μ
$
i
c
,
j
∈
[
1
,
N
]
.
EQN
.
24
[0067] The above mechanism guarantees that the entire amount, ƒ i , will be allocated fairly to each sub-claim holder, e.g., on a pro rata basis.
Method for Redistributing Receivables
[0068] A method for redistributing the receivables of asset-backed, e.g., medical- and/or healthcare-backed, securities can be based on control theory teachings, by which the only way to minimize the variance of an output is to provide a valuation feedback loop from the output. In another embodiment, a valuation feedback loop can be provided from the output, or the investment side of the medical insurance company, to the source of variation, or the claims payment side. By linking the portfolio returns of the insurance companies' investment function to the status of the claims payment function, an incentive is established to restore the payment system to equilibrium and for closing the financial loop. In this way, the bankable value of individual claims can be updated without exposing the lender to secular deterioration.
[0069] Generally, insurance companies may choose whether or not to pay their own claims, foregoing collection of investment income and vice versa. By arranging the mechanics of claims-bundling to allow companies to hold any claim liability but its own, alliances within the company can be prevented that may cause the unbalanced distribution of claim payments and receivables between investment and underwriting. As a result, the average return on any insurance company's investments would be subject to the performance of its competitors' claims paying function. Such a so-called “cross-collateralization” effect would ensure that the optimal solution is for all insurance companies to pay all of their claims on time because any attempt to withhold payment may result in reciprocal behavior from competitors.
[0070] According to one embodiment of the present invention as illustrated in the flow chart of FIG. 2 , claims are generated by medical service providers in the normal course of business in a first step. Participating medical service providers are required to enter their entire volume of individual claims available to a securitization valuation engine, which are adapted to analyze and process these claims, which will be described in more detail below. If less than all of the claims are made available to the securitization engine, “cherry picking” of some claims would bias the payment performance from predicted estimates. Also, the participation of, for example, a medical group scattered across different regions is desirable for providing geographical diversification to “medical diversification” for increasing the stability of the financing method.
[0071] In a second step, the generated individual claims are input to a claims statistical valuation engine, which is structured and arranged to generate values that relate to the expected payment amount and time-to-payment for the claims. The claims statistical valuation engine can include a software program based on evolutionary and self-learning techniques such as “Genetic Algorithms” (GA) and “Neural Networks” (NN). Alternatively, any other statistical or evolutionary technique can be used to value the target medical claims without affecting the method described herein or its embodiments.
[0072] The claims statistical valuation engine is adapted to improve the predictive power based on the received data. Databases for public and private medical claim histories for a statistically significant proportion of a known population are utilized by the valuation engine to achieve this end. Such existing national databases typically contain all of the information that is collected at the time that the claim is submitted and includes the date of claim submission as well as the date and amount of claim payment.
[0073] Prior to the start of the financing program, the national database is used to establish expected payment dates for any claim submitted by a unique medical service provider based on a vector of predictive parameters such as medical specialty, geography, patient age, condition, and other associated factors. To a large extent, the discovery of the statistical laws enabling prediction has been automated over the years and the production of payment rules via GA and NN has become a fairly routine task. As a result of this valuation step, each type of claim is associated with an expected payment amount as a percentage of its face amount and an expected payment window.
[0074] Along with these expected values, the GA and NN can derive standard deviations for the same quantities. These empirical means and standard deviations are used to advance a certain portion of the individual claim's face value to the medical service provider whose claims are included in the pool. The financial arbitration task is, in fact, the valuation engine's main function when used during real-time operations.
[0075] Prior to closing, the GA/NN processing performs codification of the parameters of synthetic pools of medical claims with given statistical payment characteristics based on the actual payment history of the large amount of claims available from the commercial databases. This synthesis creates pools of values combining a confidence interval for a cumulative payment percentage in conjunction with an associated cumulative payment window for each individual claim, to provide stability for the method. After being valued by the claims statistical valuation engine, in a third step, each individual claim is stored in a valuation database system and each claim is assigned a unique identifier and its date of submission.
[0076] The resulting claims-related characteristics of the synthetic pools are input to a Special Purpose Company's (SPC) operations in a fourth step, which directs the issuance of asset-backed, e.g., medical claims-backed, securities (ABS). After a statistically sufficient number of claims has been accumulated in a timely manner for the creation of a synthetic pool, the parameters are then dictated by a statistical payment behavior.
[0077] The SPC then issues fixed or floating income securities backed by the claims and forms an updated synthetic pool because the expected payment history of the synthetic pools is the main component in their formation. These ABS are then available for sale or purchase. Sale to other health insurance companies is desirable.
[0078] Generally, an investment in these securities has a relatively short average life because of the relatively short, expected payment window associated with typical medical claims. Nevertheless, it is common to turn a short-term security into a long-term security via a “revolving” period in capital markets operations. However, short term paper may be issued inside special vehicles or “commercial paper conduits.” Many such commercial paper conduits already exist that contain various types of assets, including medical receivables. The method of the present embodiment is independent of the expected maturity of the medical ABS that it will originate, or of the type of vehicle that will originate them.
[0079] In a fifth step, the ABS issued by the special purpose vehicles are purchased in a closing cash flow section. For instance, medical insurance companies that are obligors under the claims backing them may purchase these ABS. Proceeds of these sales flow back to the originating medical service providers as primary cash “advances.”
[0080] In the present method, the primary advance rate, which is computed as a percentage of the claim's face value, is automatically adjusted to a level commensurate with the performance of the individual medical service provider. As a result, highly efficient providers are advantaged while inefficient organizations are penalized in this method.
[0081] The automatic adjustment mechanism is accomplished via at least daily database updates from the actual claims payment experience. At predetermined set times, such as each evening for instance, the valuation engine, or GA/NN algorithm, according to the present method is “re-trained” using the most recent payment data so that advance rates are generated in line with the payment experience.
[0082] Efficient organizations tend to have payment experiences closer to the face value of the claims in comparison to inefficient organizations. Accordingly, more efficient organizations are rewarded through higher primary advances and are able to provide a monetary value for a larger portion of their total claim volume up front as compared to less efficient ones.
[0083] In a sixth step, after the origination of the claim, the insurance company or other paying entity, such as the U.S. government in the case of Medicare claims, pays the claim. Typically, the payment window falls somewhere between 45 and 180 days. The present method is structured to financially motivate the claims payment function of the obligor so that cash at the investment end is collected in the form of coupon or principal.
[0084] Ancillary support functions are used for clearing through the banking system payments made on these claims. Upon payment of the claims, a database manager is notified as to the payment amount remitted and date thereof so that the applicable database can be updated. Preferably, the database manager is notified electronically and the database is automatically updated at that time so that proper credit can be given to the originating medical service provider in real-time.
[0085] Simultaneously, the “training set” driving the valuation engine is updated and a copy of the claim's life-cycle history (from filing to payment) is archived for research purposes and the “live” claim is deemed liquidated.
[0086] Next, in a seventh step, a fee senior in priority to any or all of the other liens to which the receivable is subjected is collected by the servicing organization (third party) each time that a claim is paid. The servicing organization may consist of a clearing bank, a database manager, a financing vehicle's sponsor and an administrator. This ensures that the integrity of the entire system is predicated on the efficient operation of the servicing infrastructure.
[0087] The servicing organization fees are small compared to expected receipts and are usually calculated based on the face amount of the receivable. Although the fees are computed at the time that the claim is paid, the fees are disbursed at predetermined times, such as once a month when other trust expenses are disbursed. Once servicing fees are paid, any remaining amounts are available to security and other stakeholders in the trust.
[0088] In an eighth step, the present method performs a feedback loop inside of the insurance companies for effectively re-distributing excess liquidity to medical service providers requiring the same. This re-distribution involves a hierarchy of payments that normally begins with bond interest and principal. Providers that collect residual “equity” income from the receivables fall at the bottom of the hierarchy if the collection account has not been completely depleted at such time. These amounts are collectively referred to as a “secondary payment”, which will be discussed in more detail in the next step.
[0089] Under this framework, there may be a tendency for insurance companies to forego investment income stemming from their ABS holdings to avoid payment under their claims-related liability. Potentially, a “late payment syndrome” may still occur as a result of cooperation within the insurance company. Even though such cooperation may provide benefits from the creation of such a dialogue within the company, a better solution to the late payment syndrome problem is to bundle the claims flowing to the financing vehicle in such a way that an insurance company would be allowed only to buy securities backed by competitors' liabilities.
[0090] This bundling solution may be implemented by modifying the database management mechanics. For instance, the database may be managed to provide capital relief to cooperating insurance companies to encourage this management and create the necessary financial motivation for optimal cash management on their part.
[0091] In a next step, the calculation of secondary payments to medical service providers arising from excess cash flows according to the present embodiment further increases health care management efficiency. Two basic calculation methods of the secondary payments can be performed. The first method partitions any remaining cash flow pro rata among all of the participating providers. Therefore, on each distribution date, a hospital that has contributed 10%, for example, of the face value of all claims that have been liquidated during the previous collection period will be allocated 10% of all remaining cash in the collection account. This method may be referred to as a “socialist” calculation method for being based on a ratably equal sharing of the loss or gain associated with the receivable performance among participating providers.
[0092] In a second calculation method, cash is allocated individually according to whether or not the receivable was liquidated above or below its carrying cost. For example, if a $50 advance payment is made initially on a $100 (face amount) receivable and the receivable was liquidated for $40, no secondary payment is made to the originating provider. In fact, the trust would have suffered a $10 loss on that particular receivable. In contrast, if the receivable were liquidated for an amount above the sum of the original advance aggregate servicing fees and interest at the trust's average cost of funds during the time the claim was outstanding, say $60, then the secondary advance would equal the difference between the liquidated proceeds and that sum ($10).
[0093] The advantage of the second calculation method is that efficient organizations are not asked to subsidize inefficient ones as in the allocation of the first method. More specifically, less efficient providers may initially be given the benefit of the doubt via receiving expected advance rates on their claims in the first allocation method.
[0094] Failure to collect this average amount, however, would result in erasing any secondary advance. In addition, the next claim submitted by the same hospital would be valued at less than the national rate as a consequence of the mechanics of the valuation engine according to the present invention. This process would repeat until the supply of money from collection equals the demand from claim submission. Depending on the provider's internal cost structure, this may increase the chances for bankruptcy. Exactly the reverse phenomenon would apply to efficient providers and with correspondingly opposite results. Therefore, the normal operation of the financing vehicle for the embodiments of the present invention would automatically reward efficient providers, punish inefficient ones, protect ABS investors, and converge towards global systematic optimality at the same time.
Note Maturity
[0095] If the ABS note matures, sufficient aggregate collections are on hand at time T to refund maturing in full. In general, this can be accomplished by aggregating proceeds from all claims acting as security for the notes and allocating them to the liabilities. However, the random reimbursement process taking place is likely to disadvantage providers whose payment record is better than those that tend to collect later, since the funds of the former will be used primarily to reimburse maturing notes.
[0096] For this reason, a trust may be kept alive as long as claims can be deemed outstanding and non-defaulted, which is likely to last slightly longer than the maximum allowable note maturity, or approximately one year. Therefore, amounts collected after the note expected maturity date T but before the trust's legal final maturity date T c can be allocated on a monthly basis to medical service providers in a pro rata manner dictated by EQN. 23. The difference, however, is that, instead of the term (1−D d )αP 0 (1+r) −1 , the proper multiplier is C k P , corresponding to the aggregate pool cash flow received during period k. Consequently, during secondary or later collection periods, the holder of claim i is entitled to receive a secondary allocation, q ki , in accordance with the following formula:
[0000]
q
ki
=
C
k
P
μ
$
i
c
m
$
P
,
i
∈
[
1
,
M
]
,
k
∈
[
1
,
(
T
c
-
T
)
]
.
EQN
.
25
[0000] Neither the trustee nor the liquidity bank will have rights to these funds although the Trustee MAY still benefit from float on the amounts, C k P , pending monthly disbursement. Thus, all medical service providers benefit equally from all pool collections.
Claims Failing to Mature by T c
[0097] When claims fail to mature before a pool reaches its legal final maturity date, i.e., within the timeframe, T c , such claims are valued at zero, e.g., using the valuation algorithm, and are included in the database in a next valuation feedback-loop update. Legally, since the trust still has a security interest in the claims, e.g., via the original UCC-1 financing statements filed with the local Secretary of State at the time of the primary advance, at time T c the lien that was placed on all such claims must be released, to enable the medical service provider to collect whatever proceeds they can, without having to funnel the cash flow through the now-defunct trust.
[0098] Recalling that the medical service provider received a bona fide, primary advance on this matured claim, and may have received a string of secondary advances thereon while contributing nothing towards the reimbursement of these apparently windfall cash flows, the medical service provider will be penalized in the long term. More specifically, since the matured claim for the particular medical service provider is awarded a zero-valuation, for future claims, the primary advance will be reduced to zero as well, drastically affecting the medical service providers access to cash up-front.
[0099] Medical service providers who sell claims to a pool are assumed to be acting in good faith in their attempts to collect their claims. If this is true, it is fair to release the liens on such claims and to penalize the medical service providers by assigning a zero value to the target claims. A rational service provider would want to correct the situation and improve future collection efficiency since the proceeds of claims so sold cannot be diverted without committing fraud.
Liquidity Stand-in
[0100] To avoid default, the liquidity bank may be required to advance funds to avoid an impending default on maturing notes. When this occurs, even if the liquidity provider refunds the notes on their maturity date, T, the claim collection process continues unabated. The liquidity bank effectively becomes the only remaining fixed income creditor since the original investors have already been satisfied via the refund.
[0101] When this occurs, the liquidity bank effectively becomes a lender to the conduit, assuming, thereby, a senior position with respect to service providers. Back-stop liquidity contributions now acquire the characteristics of a loan to the service providers and are reimbursable at a prevailing or pre-determined loan rate prior to any secondary allocations to claim holders. In short, in instances in which a liquidity provider makes a loan to a particular pool, the aggregate amount(s), C k P , that become available from obligors for periodic distribution are instead allocated to the liquidity bank as partial repayment of this loan until such time as its terms are satisfied or are not satisfied and the loan is written off by the liquidity bank.
[0102] In the unlikely event that, the entire aggregate proceeds, i.e., cash flow, of all monthly periods from T until T c are insufficient to repay the loan, the liquidity bank suffers a loss of principal and/or interest.
[0103] It will be apparent to those skilled in the art that other modifications to and variations of the above-described techniques are possible without departing from the inventive concepts disclosed herein. Accordingly, the invention should be viewed as limited solely by the scope and spirit of the appended claims.
|
A method, system, and control program for expediting payment of claims to service providers and to reduce institutional capital reserves. The method includes evaluating a risk of full payment of each claim; grouping claims from a service provider(s) based on a commonality of risk; generating a security representative of the risk of the grouped claims and an investment value of the security; and exchanging a pre-payment amount to medical service providers for the security. More specifically, evaluating the risk of full payment includes comparing each individual claim to a database of historical performance of the service provider and of similar claims and, moreover, evaluating for each claim an expected payment amount and an expected time (or delay) of payment by an obligor.
| 6
|
BACKGROUND OF THE INVENTION
This invention relates to tufting machines, and more particularly to a multiple-needle tufting machine adapted to form high and low cut pile tufts in a base fabric.
Heretofore, in the art of tufting, fabric having patterned areas of high cut pile and low cut pile has been formed by cut pile looper hooks, each hook having a pair of vertically spaced bills, the lower bill being provided with a spring clip, as illustrated in U.S. Pat. No. 3,138,126 of Roy T. Card issued June 23, 1964.
These double-billed cut pile hooks were used in cooperation with a pattern controlled yarn feed. When a long length of yarn was fed to the looper, the loop was seized on the lower bill and cut by the cooperating knife to form a high cut pile tuft. When the yarn feed was starved by the pattern control, the yarn loop caught on the lower bill was pulled off of the lower bill, past the yielding spring clip, and subsequently caught upon the upper bill, where it was cut by the same knife. It has been difficult to utilize the double-billed cut pile hook because the same knife must cooperate with both the lower and upper bills to cut all loops formed on both bills.
Another method of forming patterned fabrics having high and low cut pile tufts is to initially produce a fabric having a uniform high cut pile, and then with manual shears carve out selected areas in the cut pile tufts to form patterned low pile tufted areas. This latter method is often used on scatter rugs, bath sets, and other tufted fabrics of relatively small areas, in contrast to large carpets.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide a method and an apparatus for forming both high and low cut pile in a tufted fabric with a looper having a single bill.
Another object of this invention is to provide a method and apparatus for forming patterned areas of high and low cut pile in a tufted fabric incorporating gradual transition areas between the high and low cut pile tufts to produce a "soft" sculptured appearance.
In carrying out this invention, a needle plate is utilized which has a transverse free edge terminating at the stitching station, or substantially in the transverse vertical plane of penetration of the needles, so that the needle plate fully supports the base fabric as it moves from front to rear through the machine toward the needles, but provides no support for the base fabric as it moves from the needles toward the rear of the machine and over the major portions of the looper hooks.
In addition to the utilization of the foreshortened needle plate, a conventional pattern-controlled yarn feed mechanism may be utilized to feed two different yarn lengths to the needle to create the respective high cut pile tufts and low cut pile tufts.
A looper apparatus is utilized in combination with the yarn feed control and the foreshortened plate, in which the looper hook has only a single bill to produce both high cut pile and low loop pile.
The cutting knives and the mechanisms for reciprocating the looper hooks in the knives are of conventional construction as normally used in conventional cut pile tufting machines.
As the base fabric moves away from the stitching station and the needle plate, the fabric continues, unsupported, in its normal horizontal path above the looper hooks while the long lengths of yarn are fed to the needles and seized by the looper hooks to form long loops. The knives cooperate with the rear portions of the respective looper hooks in a conventional manner to form high cut pile tufts. However, when the yarn feed is starved by the pattern controls, the yarn is drawn backward or backrobbed through the last loop caught on the looper hook bill to draw or pull down the unsupported base fabric toward the looper hooks to form short loops which are cut approximately mid-way along the looper bill to form low cut pile tufts.
It is also an important feature of this invention to provide single-billed looper hooks in which the rear portions of the bill of each hook is larger in cross-sectional dimension than the front portion. Either the vertical dimension or the transverse dimension of the rear portion of the hook bill is enlarged to further accentuate the differences in height between the long loops and short loops formed on the bill by the back-robbing of the yarn caused by the pattern-controlled yarn feed mechanism. The bills may have a front portion which has an elevated cutting edge relative to the rear portion, or the front portion may be narrower in transverse width or dimension than the rear portion of the looper hook. These front and rear portions of the bills of different dimensions are connected through a gradual merging portion which tends to arrest the rearward movement of the shortened loops until they are cut to form the low cut pile tufts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional elevation of a portion of a multiple-needle tufting machine incorporating the invention and disclosing the hooks and knives in a cutting position;
FIG. 2 is an enlarged fragmentary sectional elevation similar to FIG. 1, disclosing the hooks cooperating with the needles in a non-cutting position to form long loops;
FIG. 3 is a view similar to FIG. 2 illustrating the formation of the low loops;
FIG. 4 is an enlarged fragmentary sectional view taken along the line 4--4 of FIG. 1;
FIG. 5 is an enlarged fragmentary vertical section taken through a fabric made in accordance with this invention;
FIG. 6 is a view similar to FIG. 2, illustrating a first modified form of looper hook;
FIG. 7 is a fragmentary sectional elevation similar to FIG. 2, but taken from the opposite side, illustrating a second modified looper hook;
FIG. 8 is a fragmentary section taken along the line 8--8 of FIG. 7; and
FIG. 9 is a fragmentary section taken along the line 9--9 of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in more detail, FIG. 1 discloses a multiple-needle tufting machine 10 including a transverse needle bar 11 supporting a transversely aligned row of uniformly spaced, vertical needles 12. The needle bar 11 is vertically reciprocated by conventional means, not shown, to cause the needles 12 to move between an upper position (FIG. 1) above the base fabric 13 and a lower position (FIG. 2) penetrating the base fabric 13, so that each needle 12 will carry a yarn 14 through the base fabric 13 to form loops of tufting therein.
The base fabric 13 is supported upon the needle plate 16, made in accordance with this invention, for movement by conventional fabric rolls, not shown, such as the fabric feed rolls illustrated in the Card U.S. Pat. No. 3,138,126, in the direction of the arrow 17, that is longitudinally from front-to-rear through the machine 10.
The looper apparatus 18 which cooperates with the needles 12 includes a transverse hook bar 20 supported upon a plurality of transversely spaced brackets 22 fixed to corresponding rocker arms 23, journaled on a conventional rock shaft, not shown. The rock shaft is driven by conventional means, not shown, connected to the rocker arms 23 for limited reciprocable movement in synchronism with the reciprocable movement of the needles 12.
Supported within the hook bar 20 are a plurality of transversely spaced cut pile looper hooks 25. Each looper hook 25 includes a bill 26 having a barbed free end 27 pointing in the direction opposite the direction of fabric feed. The bill 26 projects from the neck 28 to form the throat 29. Projecting rearwardly from the neck 28 is the shank 30 received within the recess 31 of the hook bar 20, and secured therein by the set screws 32.
A knife 34 is provided for each looper hook 25 to cooperate with the corresponding hook 25 to produce cut pile tufts. The knives 34 may be mounted in knife blocks 35 carried upon a transverse knife bar 36, which in turn is carried by the arms 37 mounted on the reciprocably driven rotary knife shaft 38. The knife shaft 38 and the means for driving the hook bar 20 and the needle bar 11 are all driven synchronously by means well known in the art to cause the needles 12, the looper hooks 25 and the knives 34 to cooperate to form cut pile tufts from the yarns 14.
The needle plate assembly, including one or more needle plates 16, may be identical to the needle plate assembly disclosed in applicant's co-pending patent application Ser. No. 538,944 for "LOW PILE NEEDLE PLATE FOR A TUFTING MACHINE", filed Oct. 4, 1983 and issued on Mar. 12, 1985 as U.S. Pat. No. 4,503,787. In this co-pending application, a plurality of needle plates 16, or needle plate sections, are arranged end-to-end transversely of the tufting machine 10. Each needle plate 16 is preferably made of a rectangular sheet of unitary solid material, such as spring steel, of very thin gauge or thickness. Each needle plate 16 is mounted upon an elongated mounting plate 40 having a rear edge 41 and adapted to be supported upon the bed plate 42 of the machine 10.
Preferably, the rear top portion of the mounting plate 40 includes a recess 43 to receive the front portion of each needle plate 16, so that the free rear or trailing edge 44 of the needle plate 16 extends transversely of the machine 10 and terminates substantially in the transverse vertical plane 45 of penetration of the needles 12, that is the plane containing the vertical needle axes. In FIG. 4, the free rear edge 44 of the needle plate 16 is illustrated as substantially intersecting the transverse vertical plane 45 containing the needle axes or paths. This transverse vertical plane 45 of needle penetration may also be referred to as the stitching station.
The free rear edge 44 of the needle plate 16 is also spaced rearwardly of the rear edge 41 of the mounting plate 40 to provide clearance for the forward movement of the looper hooks 25 beneath the needle plate 16.
The needle plate 16 may be secured in the recesses 43 by any conventional securing means such as spot welds, so that the top surface of the needle plate 16 is flush with the top surface of the mounting plate 40 to provide a co-planar surface over which the base fabric 13 is supported and may be moved.
A plurality of open notches 46, preferably of uniform size and transverse spacing, may be formed in the trailing edge 44 of the needle plate 16. Each notch 46 is large enough to accommodate, that is to receive, a needle 12, as it penetrates the base fabric 13. The edges 47 and 48 of each notch 46 are spaced as closely as possible to a corresponding needle 12 to support the maximum area of the base fabric 13 adjacent the corresponding needle 12, without interfering with the movement of the respective needles 12.
As disclosed in FIG. 4, the notches 46 are V-shaped and diverge symmetrically about the longitudinal median of the angular notch 46, which median coincides with the center of each corresponding needle 12.
The diverging side walls 47 and 48 open through the trailing edge 44 of the needle plate 16 to provide ample room for the exit of each tufted loop formed on the corresponding needle 12.
Spaced behind, and in substantially the same horizontal plane as the needle plate 16, is a transverse lifter bar 50, which also supports the base fabric 13 as it moves rearwardly through the machine 10. The lifter bar 50 is spaced behind the bills 26 of the looper hooks 25 and may be located above the transverse hook bar 20.
Thus, as best disclosed in FIGS. 1, 2 and 3, the needle plate 16 provides a solid support for that portion of the base fabric 13 in the front of the machine 10 moving toward the needles 12, but provides no support for any portion of the base fabric moving from the needles 12, or the stitching station, rearward. Only the lifter bar 50 supports the rear portion of the base fabric 13. Of course, tension is maintained in the base fabric 13 by the fabric feed rolls, not shown, in the front and rear of the machine 10.
Thus, the construction of the needle plate 10 is important to the function of this invention and must have a free rear edge 44 which terminates in the vicinity of the needles 12, or the stitching station, so that the base fabric 13 is unsupported above the bills 26 of the looper hooks 25.
The yarns 14 are fed to the respective needles 12 through a conventional yarn guide 52, fixed to the needle bar 11, from a pattern-controlled yarn feed mechanism 54, of any conventional type, such as that disclosed in the prior U.S. Pat. No. 3,084,645.
The pattern-controlled yarn feed apparatus 54, shown schematically in FIG. 1, is adapted to selectively reduce the speed of the yarns 14, fed to the corresponding needles 12 in order to starve the yarn feed, and feed a short length of yarn to the corresponding looper hook 25. Thus, after a long loop 55 is formed upon a bill 26, and additional tension is created in the yarn 14 fed to that particular hook 25, then the tensioned loop 55 is backdrawn, pulling the unsupported portion of the base fabric 13 downward, as disclosed in FIG. 3, to form a short loop 56.
When the pattern-controlled yarn feed apparatus 54 is programmed to feed a normal or long length of yarn 14, the loop 55, seized by the bill 26 of the looper hook 25, will be long enough not to create any tension in the yarn loop 55 or the base fabric 13.
Accordingly, the long loop 55 will continue travelling rearwardly along the looper bill 26 toward the throat 29, where it will be cut by the normally reciprocating knife 34 to form a long cut pile tuft 57 (FIGS. 2 and 5).
The foreshortened or short loop 56, illustrated in FIG. 3, will be retarded in its rearward movement, but will still be permitted to enter the normal reciprocable cutting path of the knife 34, to be cut about mid-way between the barbed end 27 and the throat 29 to form a short cut pile tuft 58 (FIG. 5).
In this manner, a fabric 80 including high cut pile tufts 57 and low cut pile tufts 58, may be formed by a looper apparatus 18 in which each looper hook 25 has only a single bill 26.
In order to accentuate the dual heights of the cut pile, looper hooks of varying configurations may be utilized.
The looper hook 25 disclosed in FIGS. 1-3 differs from the conventional cut pile looper hook in the configuration of the lower or bottom cutting edge of the bill 26. The vertical thickness or height of the rear portion of the bill 26 is substantially greater than the corresponding vertical dimension of the front portion of the bill 26, so that the rear cutting edge portion 60 has a greater uniform depth than the front cutting edge portion 61. The cutting edge portions 60 and 61 may be joined by a forward and upward inclined shoulder or merging portion 62. The depth of the rear cutting edge portion 60 is such that when the looper hook 25 is set at its desired position below the plane of the needle plate 16, the long loops 55, seized by the looper hook 25 and formed by the long lengths of yarn 14 fed by the pattern-controlled yarn feed apparatus 54, will be long enough to pass rearwardly over the rear cutting edge portion 60 with a minimum of tension, so that the base fabric 13 remains in its normal plane of movement, as illustrated in FIG. 2. As the long loops 55 travel freely over the rear cutting edge portion 60, they are cut by the normal movement of the knife 34, to form the long cut pile 57.
However, when the yarn 14 is starved and short lengths of the yarn 14 are fed to the needles 12 and seized by the looper hook 25, the rearward movement of the short loops 56 are restrained by the merging portions 62. Continued rearward movement of the base fabric 13 and the short loops 56, strains the yarn in the short loops 56 to cause the unsupported base fabric 13 to be pulled downward toward the looper hook 25, as disclosed in FIG. 3, until the taut short loops 56 are severed by the normal reciprocal movement of the knife 34 crossing the merging zone 62, to create the short cut pile tufts 58.
Accordingly, it is critical that the merging zone 62 of the bill 26 be located in the path of the vertically reciprocable knife 34, so that the short loops 56 are eventually cut.
Each merging zone 62 also tapers gradually to guide the long-loops 55 rearward over the deeper rear cutting edge portion 60.
FIG. 6 discloses a modified looper hook 65 incorporating a bill 66 having a free front barbed end 67, neck 68, throat 69 and shank 70 received within the transverse hook bar 20. The lower or bottom cutting edge 71 of the bill 66 differs from the cutting edge portions 60-62 of the looper hook 25, in that the cutting edge 71 is in a generally straight line, but inclining upward and forward to create the differences in elevation between the rear portion and the front portion of the bill 66. Thus, the looper hook 65 functions in substantially the same way as the looper hook 25. Long loops 55 will travel un-interruptedly rearwardly along the bill 66 until the long loops 55 are cut by the vertically reciprocal knife 34. However, any short loops 56, not shown, in FIG. 6, will gradually meet resistance from the declining cutting edge 71 to create tension in the short loop 56 and pull the base fabric 13 downward, in the same manner as it is pulled downwardly in FIG. 3, until that short loop can be cut to form the short cut pile tufts 58.
FIGS. 7-9 disclose another modified form of looper hook 75 having a bill 76, in which the rear portion 77 of the bill 76. has a substantially greater width or transverse dimension than the front portion 78 of the bill 76. In a preferred form of the invention, the enlarged rear portion is formed by securing a steel pad 77 by soldering or otherwise, to the needle side of the bill 76. This pad 77 is provided with a forward tapering portion 79 (FIG. 9) to provide a gradual transition area for the rearward movement of the loops. This transitional or inclined area 79 is positioned to hold each short loop 56, not shown in FIGS. 7-9, in the path of the knife 34, by providing a barrier to prevent the rearward movement of the short loop along the bill 76, thereby creating sufficient tension to draw down the base fabric 13 in the manner disclosed in FIG. 3.
In the looper hook 75 disclosed in FIGS. 7, 8 and 9, the bottom cutting edge of the looper hook 75 may be straight and substantially level, since the transverse dimension of the rear portion 77 has been enlarged to perform the same function as the deeper rear cutting edge portions of the looper hooks 65 and 25.
In each of the tufting machines or apparatus in which the modified looper hooks 65 or 75 are utilized, the other portions of the tufting machine 10 are the same. In each case, the needle plate 13 must have a free edge portion 44 which terminates in the plane 45 of the needle penetration so that the rear portion of the base fabric 13 over the looper hooks is unsupported and thereby is free to be drawn downward toward the looper hooks to form the low cut pile tufts.
Because of the gradual retardation of the rearward movement of the short loops along the bills of the respective looper hooks, the transition between the formation of the high cut pile tufts 57 and the low cut pile tufts 58 is gradual, as clearly illustrated in FIG. 5. This gradual transition between the high and low cut pile areas of selected pattern configurations in the tufted fabric, such as a carpet, creates a unique and pleasing sculptured effect in the finished fabric. Of course, the sculptured areas are controlled by the program instructions in the pattern control yarn feed apparatus 54 so that patterns of infinite designs in high and low tufted cut pile fabrics are possible.
Also, because of the relatively thin needle plates 13, the looper hooks 25, 65 and 75 may be located quite close to the path of the moving base fabric 13 to create both high cut and low cut pile tufts of relatively short depths.
A tufted cut pile fabric, such as the fabric 80 disclosed in FIG. 5, has been tufted in which the low cut pile tufts 58 are approximately 1/4" high and the high cut pile tufts 57 are approximately 15/32" high, with a difference in height of approximately 7/32". Such a fabric, with its gradual transition areas presents an image of soft and smooth wave-type pile surfaces.
|
A sculptured high-low cut pile tufting method and apparatus for a multiple-needle tufting machine having cooperating looper hooks and knives in which the base fabric moving through the machine is supported only as it approaches the needles by a needle plate having a transverse free edge substantially in the plane of needle penetration, and does not support the base fabric leaving the needles and directly above the looper hooks. The length of yarns fed to the needles are controlled by a pattern-controlled yarn feed apparatus. When short lengths are fed to the needles, the seized yarn causes the base fabric to be drawn toward the loopers to form short loops which are cut to form low cut pile tufts, while long lengths of yarn fed to the needles form long loops on the looper hooks which are cut to form cut pile tufts while the base fabric maintains its normal longitudinal path through the tufting machine. The apparatus is also characterized by looper hooks of unique construction whose bills have larger rear portions than front portions so that the larger rear portions assist in arresting the longitudinal movement of the short loops on the hook to form low pile.
| 3
|
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/348,790, filed Jan. 14, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a novel catalyst for use in reforming of naphtha and a reforming process using that catalyst.
[0004] 2. Brief Description of Related Art
[0005] Catalytic reforming is a major petroleum refining process used to raise the octane rate of naphthas (C5 to C11 hydrocarbons) for gasoline blending. Catalytic reforming is also a principle source of aromatic chemicals (benzene, toluene, and xylenes) via conversion of paraffins and naphthenes to aromatics. The principle chemical reactions which occur during catalytic reforming include dehydrogenation of cyclohexanes to aromatics, dehydrocyclization of paraffins to aromatics, dehydroisomerization of alkylcyclopentanes to aromatics, isomerization of normal paraffins to branched paraffins, dealkylation of alkylbenzenes and hydrocracking of paraffins to light hydrocarbons, i.e. methane, ethane, propane, and butane. The latter reaction is undesirable and should be minimized since it produces light hydrocarbons not suitable for gasoline blending which have less value than gasoline fractions.
[0006] Reforming is carried out at temperatures of 800° F. to 1100° F., pressures of 50 to 300 psi, weight hourly space velocities of 0.5 to 3.0 and in the presence of hydrogen at hydrogen to hydrocarbon molar ratios of 1 to 10.
[0007] Reforming catalysts currently widely used in commercial reformers are platinum on an alumina substrate, and platinum plus a second promoting metal such as rhenium, tin, or indium on alumina. These catalysts are bifunctional, i.e., the dehydrogenation reactions required in the reforming process are accomplished on the catalytic metal in the catalysts and the isomerization and cyclization reactions also required in reforming are accomplished on acid sites on the alumina catalyst support. Undesirable hydrocracking reactions which break C6+ paraffins down to lower molecular weight hydrocarbons and reduce selectivity to aromatics occur primarily on the acid catalytic sites.
[0008] Alumina based reforming catalysts demonstrate reasonably high selectivities for converting C8+ paraffins and naphthenes to aromatics but are less satisfactory for aromatizing C 6 to C 8 paraffins because they tend to hydrocrack more of the lower paraffins to low value fuel gas rather than they convert to aromatics.
SUMMARY OF THE INVENTION
[0009] This invention provides a modified refractory aluminum oxide catalyst for use as a naphtha reforming catalyst which produces a reformate having enhanced C 5 + yields and particularly enhanced yields of aromatic compounds as compared to a similar unmodified catalyst. More specifically, the invention provides a modified platinum-containing refractory aluminum oxide reforming catalyst containing from about 0.1 to about 10% by weight silica.
[0010] The invention also provides a process for reforming naphtha comprising contacting a naphtha stream under reforming conditions with the modified catalyst and recovering a reformate having an enhanced content of C 5 + and aromatic compounds.
DETAILED DESCRIPTION OF THE INVENTION
[0011] The catalyst support used in the present invention is a porous refractory aluminum oxide material such as alumina, alumina-titania, alumina-chromia and the like, in combination with a Group VIII noble metal such as platinum and at least one other metal, such as indium, rhenium, tin, gallium, palladium, lead, iron, or tungsten, and, for certain uses, a halogen component. The support component of the catalyst is preferably a porous, adsorptive material having a surface area, as determined by the Brunauer-Emmett-Teller (BET) method, of about 20 to 800, preferably 100-300 square meters per gram. This support material should be substantially refractory at the temperature and pressure conditions utilized in any given hydrocarbon conversion process.
[0012] Alumina in its gamma or eta forms is the preferred catalyst support. Typically, the support materials are prepared in the form of spheres, granules, powders, extrudates or pellets. The precise size or shape of the support material used is dependent upon many engineering factors not within the purview of the instant invention. It is also within the scope of this invention to have all the metals of the multi-metallic platinum-containing catalyst on the same support in one particle, e.g., platinum and iridium on alumina, or as a mixture of separate particles, e.g., platinum on alumina mixed with indium on alumina.
[0013] The multi-metallic platinum-containing catalyst may be prepared employing simple impregnation techniques. Such a catalyst may be prepared by impregnating the support material with a solution of a soluble platinum compound and soluble compounds of any additional metals to be incorporated in the catalyst. Generally, an aqueous solution of the metal compounds is used. The support material may be impregnated with the various metal-containing compounds either sequentially or simultaneously. The carrier material is impregnated with solutions of appropriate concentration to provide the desired quantity of metals in the finished catalyst. In the case of indium, compounds suitable for the impregnation onto the carrier include, among others, chloroiridic acid, indium tribromide, indium trichloride, and ammonium chloroiridate. In the case of platinum, compounds such as chloroplatinic acid, ammonium chloroplatinate, and platinum amine salts can be used. Additional catalyst metals may be incorporated onto the support by employing compounds such as perrhenic acid, ruthenium trichloride, rhodium trichloride, rhodium nitrate, palladium chloride, palladium amine salts, stanous chloride, silver nitrate, cobalt nitrate, nickel nitrate, and the like. The preferred catalyst manufacturing technique involves contacting a previously prepared support, such as alumina with an aqueous solution of indium and platinum compounds, alone or in combination with a compound of at least one additional catalyst metal.
[0014] After impregnation of the carrier, the composite catalyst is dried at a temperature varying from about 220° to 250° F. The catalyst may be dried in air at the above stated temperatures or may be dried by treating the catalyst in a flowing stream of inert gas or hydrogen. The drying step may be followed by an additional calcination step at temperatures of about 500° to 700° F. Care must be taken to avoid contacting the catalyst at temperatures in excess of about 700° F. with air or other gases of high oxygen concentration. If the catalyst is contacted with oxygen at too high a temperature, at least a portion of the non-platinum component, such as indium, will be oxidized, with loss of surface area, to crystallites of indium oxide.
[0015] Additional materials may be added to the platinum-containing catalyst composites to assist in the promotion of various types of hydrocarbon conversion reactions for which the catalyst might be employed. For example, the naphtha reforming activity of the catalyst is enhanced markedly by the addition of a halogen moiety, particularly a chlorine or fluorine moiety, to the catalyst. The halogen should be present in the catalyst in amounts varying from about 0.1 to about 3.0 weight percent, based on the total dry weight of the catalyst. The halogen may be incorporated into the catalyst at any suitable stage in the catalyst manufacturing operation, i.e. before, during or after incorporation of the active metal component onto the support material. Halogen is often incorporated into the catalyst by impregnating the support with halogen-bearing metal compounds such as chloroiridic acid. Further amounts of halogen may be incorporated in the catalyst by contacting it with hydrogen fluoride, ammonium fluoride, hydrogen chloride or ammonium chloride, either prior to or subsequent to the impregnation step. Other components may also be added to the catalyst composite. For example, the catalyst may be sulfided before or during use.
[0016] In accordance with this invention, the bifunctional aluminum oxide catalysts as described above are modified by ex-situ treatment with silica or an organosilicon compound, followed by calcination to convert the organosilicon compound to silica. The bifunctional aluminum oxide catalysts contain both metal sites and acid sites and it is believed that the presence of silica in the catalyst reduces the acidity in the catalyst thereby decreasing its cracking activity with a consequent enhancement of the content of C 5 + and aromatic compounds present in the reformate.
[0017] The incorporation of silica (SiO 2 ) into the catalyst (hereafter referred to as silylation) may be accomplished by mixing the catalyst with an aqueous dispersion of colloidal silica to impregnate the aluminum oxide with silica, followed by drying the resulting mixture at a temperature of from about 100 to about 400° C. for a period of from about 0.5 to 10 hours.
[0018] Yet another silylation technique is analogous to methods used to selectivate zeolite catalysts used in isomerization and separation processes such as described in U.S. Pat. Nos. 5,476,823 and 5,365,003. This method involves contacting the catalyst particles with an organo silicon compound or solvent solution or aqueous emulsion thereof to form a coating on the surface of the particles of catalyst, followed by calcination to convert the organic compound to SiO 2 .
[0019] Representative silicone compounds include dimethyl silicone, diethyl silicone, phenylmethyl silicone, methylhydrogen silicone, ethylhydrogen silicone, phenylhydrogen silicone, methylethyl silicone, phenylethyl silicone, diphenyl silicone, methyltrifluoropropyl silicone, ethyltrifluoropropyl silicone, polydimethyl silicone, tetrachlorophenylmethyl silicone, tetrachlorophenylethyl silicone, tetrachlorophenylhydrogen silicon, tetrachlorophenylphenyl silicon, methylvinyl silicone and ethylvinyl silicone. The silicone compound need not be linear, but may be cyclic, for example, hexamethyl cyclotrisiloxane, octamethyl cyclortetrasiloxane, hexaphenyl cyclotrisiloxane and octaphenyl cyclotetrasiloxane. Mixtures of these compounds may also be used, as may silicones with other functional groups.
[0020] Other silicon compounds, including silanes and alkoxy silanes, such as tetramethoxy silane, may also be utilized.
[0021] Preferred silicon-containing silylation agents include dimethylphenylmethyl polysiloxane (e.g., Dow-550) and phenylmethyl polysiloxane (e.g., Dow 710). Dow-550 and Dow-710 are available from Dow Chemical Co.
[0022] The silicon compound may be applied to the aluminum oxide powder in neat form or as a solvent solution or aqueous emulsion. After application of the silicon compound to the surface of the aluminum oxide catalyst, the catalyst is calcined at 350-550° C. in air from a period of 1-24 hours to convert the organosilicon compound to silica. The process may be repeated one or more times to achieve the desired content of silica in the catalyst.
[0023] The final content of silica present on the surfaces of the aluminum oxide catalyst powder may range from about 0.1 to 10 wt %, more preferably from about 1 to 6 wt %.
[0024] The resulting silica-modified catalyst may then be subjected to an oxychlorination treatment to re-disperse the platinum metal and establish the appropriate halogen level in the catalyst.
[0025] Such a process involves treating the catalyst with a mixture of oxygen-containing and chlorine-containing gases at a temperature of up to about 1250° F. to bring about a reduction in size of the platinum crystallites and reducing the treated catalyst in the presence of hydrogen at a temperature in the range of about 400°-1000° F. Such an oxychlorination process is described in U.S. Pat. No. 3,134,732, the complete disclosure of which is incorporated herein by reference.
[0026] The catalysts of the invention are particularly useful in promoting the dehydrogenation, isomerization, dehydrocyclization and hydrocracking reactions that occur in a naphtha hydroforming process.
[0027] In a naphtha hydroforming process (reforming) a substantially sulfur-free naphtha stream that typically contains about 15 to 80 volume percent paraffins, 15 to 80 volume percent naphhthenes and about 2 to 20 volume percent aromatics and boiling at atmospheric pressure substantially between about 80° and 450° F., preferably between about 150° and 375° F., is contacted with the platinum-containing catalyst composite in the presence of hydrogen. The reactions typically occur in a vapor phase at a temperature varying from about 650° to 1100° F., preferably about 750° to 1000° F. Reaction zone pressures may vary from about 1 to 50 preferably from about 5 to 30 atmospheres. The naphtha feed stream is passed over the catalyst composite at space velocities varying from about 0.5 to 20 parts by weight of naphtha per hour per part by weight of catalyst (W/hrW) preferably from about 1 to 10 W/hr/W. The hydrogen to hydrocarbon mole ratio within the reaction zone is maintained between about 0.5 to 20, preferably between about 1 and 10. During the reforming process, the hydrogen used may be in admixture with light gaseous hydrocarbons. In a typical operation, the catalyst is maintained as a fixed bed within a series of adiabatically operated reactors. The product stream from each reactor (except the last) in the reactor train is reheated prior to passage to the following reactor. As an alternate to the above-described process, the catalyst may be used in a moving bed in which the naphtha charge stock, hydrogen and catalyst are passed in parallel through the reactor or in a fluidized system wherein the naphtha feed stock is passed upwardly through a turbulent bed of finely divided catalyst particles. Finally, if desired, the catalyst may be simply slurried with the charge stock and the resulting mixture conveyed to the reaction zone for further reaction.
[0028] The following examples are illustrative of the invention. The base catalyst before silica treatment is a bimetallic CCR reforming catalyst with Pt/Sn loading. Catalyst properties are shown in Table 1.
TABLE 1 Catalyst Properties Property Pt/Sn, wt. % 0.3/0.27 Surface Area, m 2 /g 200 Support Al 2 O 3 Chloride, wt % 1.23
EXAMPLE 1
Silica Modification of the Catalyst Base
[0029] The catalyst described above was impregnated with Ludox LS 30 colloidal silica (30 wt % suspension in water) as follows. 50 g Ludox LS 30 was combined with 110 g water. This suspension was slowly added to 200 g of the catalyst at room temperature to impregnate the catalyst with silica. The material was then dried for three hours at 650F in 5 v/vol air. Four 200 g batches of material were prepared in this manner and combined for further experiments.
EXAMPLE 2
Oxychlorination of Catalyst of Example 1
[0030] Prior to experiments, the catalyst of Example 1 was treated in a Moving Bed Regenerator to re-disperse platinum and establish the appropriate chloride level. A chloride level of about 1.1 wt. % was targeted. During this procedure, excess silica was removed from the catalyst.
EXAMPLE 3
[0031] The base catalyst and the catalyst of Example 2 were evaluated using a moving bed, four reactor pilot plant.
[0032] Tables 2 and 3 respectively show the operating conditions and the composition of the naphtha used.
TABLE 2 Operating Conditions Process Variable Value Feed Light naphtha Average Reactor Pressure, psia 135 High Pressure Separator Pressure, 115 psia Weight Hourly Space Velocity 1.5 (WHSV), hr −1 Hydrogen Recycle Ratio (HRR), 2.2 mol/mol C5+ RON 100.25 Catalyst Circulation, g/hr 5
[0033] [0033] TABLE 3 Feed Composition Paraffins 55.9 Naphthenes 31.1 Aromatics 13.0
[0034] The modified catalyst of Example 2 was placed in the reactor and the naphtha feed was introduced. Reactor inlet temperature was maintained at about 990° F. so as to target C 5 + octane number of 100.25. After about 12 days of service, the reformate yield was evaluated.
EXAMPLE 4
[0035] The unmodified base catalyst was introduced into the reactor and reforming was conducted under the same process conditions as described in Example 3. Temperature was adjusted to obtain the desired octane. Table 4 below shows the yield summaries for the catalysts of examples 3 and 4 using the light naphtha described in Table 3 as the feed.
TABLE 4 Yield Summaries Base Case Si-modified Yields, # on (Catalyst of (Catalyst of feed Example 4) Example 3) Difference C5+ vol % 71.45 72.87 1.42 C6+ vol % 61.80 63.64 1.84 H2 wt % 2.55 2.72 0.17 C1 + C2 wt % 4.51 4.38 (0.13) C3 + C4 wt % 14.67 13.00 (1.67) NC5 vol % 3.57 3.40 (0.17) IC5 vol % 5.49 5.25 (0.24) NC6 vol % 3.65 3.81 0.16 IC6 vol % 10.11 10.64 0.53 NC7 vol % 0.26 0.30 0.04 IC7 vol % 1.60 1.63 0.03 Benzene vol % 8.04 8.32 0.28 Toluene vol % 18.23 18.64 0.41 Xylene vol % 12.76 13.22 0.46 EB vol % 2.15 2.19 0.04 C9+ vol % 4.87 4.80 (0.08) BTX wt % 46.91 48.29 1.38 WAIT, ° F. 989.83 992.07 2.24 Coke, wt % ≈5.00 ≈4.50
[0036] It is to be noted from Table 4 that the Si-modified catalyst of the invention results in increased yields of benzene, toluene and xylenes, as well as an increased yield of C5+ compounds.
[0037] It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.
|
A platinum-containing aluminum oxide reforming catalyst is disclosed which is modified by incorporating silica therein. The resulting catalyst is used to reform naphtha yielding a reformate having a higher C5 and aromatic content than that achieved using a similar catalyst which contains no added silica.
| 1
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. Ser. No. 957,022, filed on Nov. 1, 1978 now abandoned, and discloses a microstructured article similar to that disclosed in U.S. Pat. No. 4,114,983, which patent issued Sept. 19, 1978, to K. N. Maffitt, H. U. Brueckner and R. D. Lowrey.
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an article having a microstructured surface, and the resultant article. The surface of the article thus forms an interface between the article and the adjacent medium, which if of differing indices of refraction, results in enhanced light transmission and decreased reflectance without producing significant diffuse scattering.
Various types of coatings to reduce reflectivity and improve the transparency of articles such as lenses and windows, and to improve the efficiency of solar cells and solar absorption panels are well known. Perhaps the best known are the single, or preferably multiple, layer interference coatings used on optical lenses, filters and as antireflecting films used on windows. While such coatings are desirable in that they are durable and are known to provide an extremely low reflectivity at specific wavelengths, they exhibit a number of limitations. For example, the optical characteristics of such single layer films are highly sensitive to the wavelength, such that multiple layer coatings must be employed. However, if such multiple layer coatings are used, a significant sensitivity to the direction of incident light results. Interference coatings providing antireflecting characteristics which are simultaneously independent of the incident wavelength and in which the antireflection is substantially uniform over a wide range of incident angles, are, therefore, not known. Furthermore, such interferrometric films are relatively expensive to produce, requiring careful control of the thickness of the coating as well as multiple coating operations.
In addition to such articles in which the reflectance therefrom is reduced via a coating having optical interference characteristics, it is also known to provide articles in which the reflectance is reduced by providing a microstructured surface over which the effective index of refraction varies continuously from the substrate to the ambient environment. See, for example, U.S. Pat. No. 2,432,484 (Moulton) and the above referenced patent to Maffitt et al, which patent is assigned to the present assignee. It is believed that the highly sensitive vision of nocturnal insects, such as moths, is at least partly due to the low reflectivity from the surface of the eyes due to the presence of such a microstructure on the surface of the eye. G. C. Bernhard et al, Acta Physiologica Scand., Vol. 63 243, pp. 1-75 (1965).
Another example of a method of producing an antireflective surface utilizing a regular array of microprotuberances is disclosed in U.S. Pat. No. 4,013,465 (Clapham).
Solar collectors utilizing porous coatings to increase the absorptivity and to minimize the radiation loss due to reverse reflected radiation (visible or IR) are also known. It is also known to utilize micropores, grooves or other "textural" effects in such devices to effect an increase in absorptance. J. Vac. Sci. Tech., Vol. 12, No. 1, Jan/Feb (1975). For example, U.S. Pat. No. 3,490,982 (Sauveniere et al) discloses a method of treating a glass surface to provide a microstructured surface exhibiting reduced reflectivity. Commercial acceptance of some of the coatings, surface treatments and the like disclosed in the above cited references have not proven commercially acceptable, possibly due to the instability of the surfaces, cost or inability to provide uniform surfaces over extended areas.
Articles having a microstructured surface are also disclosed in U.S. Pat. No. 4,190,321, (Dorer & Mikelsons) which patent issued Feb. 26, 1980, and is assigned to the same assignee as the present invention. That patent discloses the treatment of an aluminum surface to form thereon an aluminum hydrate, or boehmite composition having a plurality of randomly positioned leaflets which give the treated surface an antireflecting characteristic. In a somewhat similar manner, U.S. Pat. Nos. 3,871,881, 3,975,197 and 4,054,467 disclose prior inventions of Mikelsons in which aluminum surfaces are treated to provide microstructured boehmite surfaces by which other coatings, applied to the aluminum prior to treatment, become tenaciously bonded to the aluminum. Also, U.S. Pat. No. 3,664,888 (Oga et al) depicts an electrochemical process for treating aluminum or aluminum alloy surfaces which etches the surface, leaving minute irregularities and pinhole cavities which are said to provide mechanical anchorage for subsequently applied resin coatings.
SUMMARY OF THE INVENTION
In contrast to prior art microstructured articles such as that of Maffitt et al (U.S. Pat. No. 4,114,983), in which a homogenous polymeric article is provided with a microstructured surface by replication of a master surface into a polymeric material, the present invention is directed to an article in which a durable, microstructured surface is formed directly on the article itself, thus eliminating any need for replication.
Such an article, preferably formed of a variety of polymers such as are increasingly commercially important, is formed, according to the method of the present invention, by first selecting a substrate having a predetermined rate of sputter etching under a given set of sputtering conditions. A material having a lower rate of sputter etching under the same set of conditions is then applied to the substrate in an average thickness in the range of 0.1 to 10 nm, to form a composite surface on which portions of the underlying substrate are exposed between discontinuous microislands of the material. Finally, the composite surface is sputter etched under the given set of sputtering conditions to preferentially etch the exposed portions of the higher sputtering rate substrate, while the discontinuous microislands are etched at a lower rate, resulting in a topography of micropedestals which vary in height within a range of approximately 0.01 and 0.2 μm and which are separated from adjacent micropedestals a distance within a range of approximately 0.05 to 0.5 μm. Such a topography of micropedestals has been found to provide a surface exhibiting substantially decreased specular reflectance, without an attendant increase in diffuse scattering as well as providing improved anchorage for subsequently applied coatings.
In a preferred embodiment, the substrate is selected of a substantially transparent organic polymer, such as a clear acrylic. Upon formation of the micropedestals thereon, the resultant surface exhibits enhanced transmittance as well as decreased reflectance. Even when the article per se is not transparent, such as when it includes a substrate on top of another base material, the substrate nonetheless serves as a non-reflecting, non-absorbing conduit to transmit incoming radiation as efficiently as possible, either completely through the article, as in the case of a lens or the like, or into a radiation absorbing member, as in the case of a heat absorber.
Further, it has been found preferable to utilize a refractory metal such as chromium to form the discontinuous islands. When applied to most polymers, such a metal, either in its metallic state or as converted to a metallic oxide, exhibits a rate of sputter etching which is typically at least an order of magnitude less than that of the polymer, thus resulting in the rapid formation of the micropedestals during the sputter etching operation. This operation is desirably carried out in a reactive atmosphere, e.g. oxygen. Such an atmosphere is believed to promote the formation of metallic oxides which frequently have an appreciably lower rate of sputter etching than that of the metal. Also, such a reactive atmosphere is believed to promote general degradation of polymeric substrates such that the rate of sputter etching is increased.
The articles of the present invention are characterized both by the presence of the micropedestals and the attendant reduction in specular reflectance and enchanced adherence properties, but also by the presence of a generally detectable lower sputtering rate material having a lower rate of sputter etching which remains after termination of the sputter etching operation, and which may contribute to the increased interface transmittance.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1: An electron micrograph of a microstructured surface of an article prepared according to one embodiment of this invention;
FIG. 2: Curves A and B respectively show the percent of total reflectance as a function of wavelength for a prior art, untreated surface of a polycarbonate article and for surfaces of a polycarbonate article, one surface of which was treated with chromium pursuant to one embodiment of the present invention;
FIG. 3: Curves A and B respectively show the percent of total transmission as a function of wavelength for a prior art untreated polycarbonate article and for a polycarbonate article treated on one surface with chromium pursuant to one embodiment of the present invention;
FIG. 4: Curves A, B, C and D, respectively, show extent of diffuse scattering, i.e. scattering as a function of angle off normal incidence for the unscattered beam (A) the extent of scattering for a prior art untreated polycarbonate article (B), a polycarbonate article treated on both surfaces pursuant one embodiment of the present invention (C), and a polycarbonate article treated under conditions outside the limits of the present invention (D);
FIG. 5: Curves A and B respectively, show the percent total reflectance as a function of wavelength for prior art untreated surface of an oriented polyester article and for surfaces of an oriented polyester article, both of which were treated using chromium pursuant one embodiment of the present invention;
FIG. 6: Curves A and B respectively show the percent total transmission as a function of wavelength for a prior art untreated oriented polyester article and for an oriented polyester article treated on both surfaces with chromium pursuant one embodiment of the present invention;
FIG. 7: Curves A and B respectively show the percent total reflectance as a function of wavelength for prior art untreated surfaces of an oriented polyester article and for surfaces of an oriented polyester article, both of which were treated using glass pursuant one embodiment of the present invention; and
FIG. 8: Curves A and B respectively, show the percent total transmission as a function of wavelength for a prior art untreated oriented polyester article and for an oriented polyester article treated on both surfaces with glass pursuant one embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the present invention, a variety of composite surfaces have been found to provide the required differential rates of sputter etching. Such differences in etch rate or sputter yield are controlled by local variations in composition or crystallinity. While the preferred method of producing and controlling such variations is directed to the placement of a discontinuous metal or metal oxide film on an organic polymeric surface, other techniques are similarly within the scope of the present invention. For example, discrete metal particles may be applied to an organic polymer substrate. Such particles, however, are usually relatively large in size and often rearrange in clumps such that the resultant discontinuous microislands are sufficiently large that after the composite surface is sputter etched, the micropedestals are so large that the reflection characteristics of the surface are outside the limits desired of the invention.
Similarly, the sputter etching rate of crystalline polymers has been found to be different in many instances from that of the non-crystalline analog thereof. Accordingly, if a polymer is provided in which both crystalline and non-crystalline regions are present, the difference in sputter etching rate may be utilized to provide the requisite micropedestals. However, since the differences in sputter etching rate for most materials is rather small, the time required to provide the desired amplitude of micropedestals may be much longer than that necessary utilizing other methods.
Another technique involves the preparation of a polymer with metal oxide particles ranging in diameter between 10 and 50 nanometers uniformly dispersed within the polymer. Upon sputter etching, the metal oxide particles will be sputter etched at a rate less than that of a surrounding polymer. However, while such composites are available, the number of polymer choices is somewhat limited, thus restricting the utility of such a technique.
In a preferred embodiment, the structure required to reduce specular reflections below a desired level of 1% per surface across the visible spectrum is random in height within the limits of 0.01 to 0.2 micrometers, and wherein a predominant number of micropedestals in the structure are in the range of 0.1 to 0.2 micrometers. The peak-to-peak separation is also random and preferably ranges between the limitation of 0.05 to 0.5 micrometers, with the preferred separation being in the range of 0.1 to 0.2 micrometers.
In a preferred embodiment, such structures are preferably formed by the following series of steps: A substrate having a range of sputter etching under a given set of sputtering conditions is first selected. Preferably such a substrate is an organic polymer such as polyester, cellulose acetate butyrate, acrylics, and polycarbonates. Onto such a substrate is then applied, such as by vacuum evaporation or sputtering deposition, discontinuous microislands of a material having a rate of sputter etching lower than that of the substrate under the same set of sputter etching conditions. Such a material is applied in an average thickness in the range of 0.1 to 10 nanometers, with a preferred thickness in most cases being less than 2.0 nm. Such an average thickness is sufficiently thin that the material is deposited in the aforementioned discontinuous microislands. While the particular method by which the microislands are formed is not overly critical, it has been found that sputter deposition is preferred due to the fact that improved control is obtainable. Generally, sputter deposition proceeds at a lower rate. Furthermore, sputter deposited material is believed to arrive at the substrate surface with a higher kinetic energy than that of evaporated atoms, for example, and hence have a higher mobility. This higher mobility apparently allows the deposited material to move about on the substrate surface to coalesce with other material, thus remaining as discontinuous microislands having larger average thicknesses than that obtainable with evaporated coatings.
The thus formed composite surface is then sputter etched. Since the discontinuous microislands formed from the deposited films or deposition of fine particles or the like are formed from the materials having a rate of sputter etching which is lower than that of the substrate, the exposed portions of the underlying substrate then etch at a rate which is greater than that of the microislands. This differential etching rate results in the formation of a random topography of micropedestals which vary in height within a range of approximately 0.01 and 0.2 nm. The micropedestals are separated from the adjacent micropedestals a distance within the range of approximately 0.05 to 0.5 nm. The peak-to-peak spacing of the resultant micropedestals is controlled by the spacing of the discontinuous microislands, whereas the overall height of the micropedestals is controlled by a combination of the sputter etching time and power, and the difference in the sputtering yield between the material used to form the microislands and that of the underlying substrate.
The desired differences in the sputter etching rate of the substrate and that of the materials applied to provide the discontinuous microislands thereon is typically in the range of a factor of 10-1000. For example, most suitable polymers have been found to sputter etch at a rate ranging between 150 and 300 nanometers per minute under conditions of approximately 0.4 watts per square centimeter at a pressure of 5 to 10 microns of oxygen. Such sputter etching rates are generally a factor of 2 to 4 times less under similar sputter etching conditions when a partial atmosphere of an inert gas such as argon is used. Where microislands formed of a noble metal are utilized, the sputter etching rate is approximately 1/10 to 1/25 that of typical polymers. If a refractory metal such as chromium is utilized, the sputter etching rate has been found to be typically less than 1/10 that of such polymers, and where a metal oxide is provided, the sputtering rate may be typically as low as one-one hundredth that of the underlying substrate.
While organic polymeric substrates are of primary importance in the present invention, known inorganic substrates are similarly encompassed within the present invention. For example, quartz substrates may be utilized by overcoating the substrate with discontinuous microislands of a polymer, after which the composite surface is differentially sputter etched using a plasma containing a material such as trifluoromethane.
Maximization of differences in etch rate, thus reducing the time required to produce a reflection reducing microstructure on many polymer substrates is best achieved by reactively sputter etching in oxygen. The use of oxygen causes an oxide to form on the discontinuous film coating, thus reducing its etch rate while simultaneously reacting with the polymer and increasing its etch rate. Typically, the etch rate of polymers such as polyester and CR-39 is two to four times higher in oxygen than in argon.
The average film thickness required to form a discontinuous film suitable for production of reflection reducing microstructures is a function of the material being deposited, the composition and structure of the substrate, the substrate temperature, the deposition method and rate and vacuum conditions.
Some non-limiting combinations which have been found to produce the desired microstructures are listed below.
______________________________________ Film DepositionSubstrate Composition Composition Method______________________________________Polyester (oriented) Cr, glass, Al SputteringPolyester (amorphous) Au SputteringCellulose Acetate Glass, Cr SputteringButyrateAcrylic (Rohm and Haas) Cr Sputtering orType 147F Evaporationmethyl methacrylatePolycarbonate Cr SputteringCR-39, a proprietary polycarbonate producedby Pittsburg Plate Glass Inc. (PPG Corp.)especially for optical lens, etc., and whichis composed of diallyl glycol carbonate.______________________________________
As will become more apparent when the results of the specific examples to be discussed later are shown, the method of this invention has the following advantages over heretofore taught methods for producing antireflecting surfaces:
1. The method can be applied to any material that has a sputtering yield higher than that of metal oxides.
2. Microstructure surfaces can be produced on polymers, such as oriented polyester, which are difficult to emboss.
3. The method is adaptable to on-line continuous processing of a web.
4. The resulting microstructured surfaces appear to be more rugged than prior art microstructured surfaces.
5. The need for an expensive mold subject to wear and filling is eliminated.
6. The microstructure dimensions can be varied over a broad range.
7. The substrate may be of any shape so long as the surface can be coated.
A better understanding of the importance of the topographic control of a microstructured surface provided in this invention can be attained by reference to the following specific examples and accompanying figures.
FIG. 1 is a scanning electron micrograph showing a typical microstructured surface of an article of the present invention. As shown in FIG. 1, a typical polymeric optical article according to the present invention has a microstructured surface topographic which can generally be described as a plurality of randomly positioned peaks, a predominant number of which range in amplitude between 0.020 to 0.20 μm. In such articles, the reflectivity is significantly reduced from similar but untreated articles, and if the articles comprise a transparent substrate, the transmissivity is appreciably increased. It is believed that these characteristics are due to a gradation in the index of refraction between that of the medium outside the surface of the article and that of the bulk of the article. In the present invention, the changes in the effective index of refraction varies over a distance ranging between the wavelength of light down to one-tenth that wavelength. Accordingly, it is believed that it is the property of a graded change in the refractive index over this distance which renders the article of the present invention antireflecting, and, under certain conditions, more transmitting over an extended range of optical wavelengths.
EXAMPLE 1
A protective paper covering having a pressure-sensitive backing was stripped from a 15 cm×20 cm×0.16 cm piece of Homalite® type 911 (an ophthalmic grade polycarbonate, generally known as CR-39) obtained from the SGL Industries Inc. Wilmington, Del. The small amounts of adhesive remaining on the polymer surface were removed by scrubbing the surface using 95% ethanol. The surface was then further cleaned with a mild detergent and water, followed by a water rinse and a final 95% ethanol (0.8 micron filtered) rinse. The sample was blown dry with nitrogen gas and, if not further processed, stored in a clean laminar flow hood until further processing.
Further processing was done in a Vecco® model 776 radio frequency diode sputtering apparatus operating at a frequency of 13.56 MHz, modified to include a variable impedence matching network. The apparatus included two substantially parallel shielded circular aluminum electrodes 40.6 cm in diameter with a 5 cm gap between them. The electrodes were housed in a glass jar provided with R.F. shielding. The bell jar was evacuatable by means of a mechanical fore/roughing pump with a water cooled trap and oil diffusion pump. The cathode pedestal was cooled by circulating water, and covered by a plate of double strength window glass to prevent sputtering of the underlying aluminum electrodes.
The sample CR-39 panel was centrally attached to the aluminum anode plate by means of small pieces of pressure sensitive adhesive tape at the corners of the sample, with the surface of the CR-39 panel to which a sputtered film was to be applied facing the cathode electrode. The source of the material to be sputter deposited was an evaporated chromium coating in excess of 0.05 μm thick on a plate of double strength window glass, which plate was placed over the glass covered cathode electrode, with the Cr coating facing the CR-39 panel on the anode.
The system was then evacuated to 2×10 -5 torr, and argon gas introduced through a needle valve. An equilibrium pressure of 6 to 9×10 -3 torr was maintained as argon was continuously introduced and pumped through the system.
R.F. energy was capacitively coupled to the cathode, initiating a plasma and was increased until a cathode power density of 0.38 watts/cm 2 is reached, thus causing chromium to be sputtered from the cathode and deposited on the opposing anode. The sputter deposition of chromium metal onto the sample was continued for seven minutes±ten seconds. Reflected power was less than 2%. The coupling capacitance was continuously manually adjusted to maintain the above stated power density. Subsequent measurements using an Airco Temescal FDC 8000 Film Deposition Controller to monitor film thicknesses as a function of time under identical conditions revealed that the sputtered discontinuous film was being deposited at a rate of approximately 0.13 nm/minutes. In seven minutes, the average film thickness was, therefore, approximately 0.9 nm.
The R.F power was then shut off, the argon needle valve closed and the system let up to atmospheric pressure using 0.2 micron filtered air. The chromium coated double strength window glass was removed, revealing the clean uncoated glass covering the aluminum cathode plate. The sample was detached from the anode and placed on the clean glass covered cathode such that the surface with sputter deposited chromium on it faced the anode.
The system was next evacuated to 2×10 -5 torr and oxygen introduced by means of a needle valve. An oxygen equilibrium pressures of 6×10 -3 torr was maintained in the system and R.F. energy capacitively coupled to the cathode, initiating a plasma. The energy was increased until a cathode power density of 0.31 watts/cm 2 was reached. The reactive sputter etching was continued for 60 seconds±3 seconds.
A microstructured surface consisting of chromium or chromium oxide capped pyramid-like micropedestals having a peak-to-peak spacing small compared with the wavelengths of the visible light, such as shown in FIG. 1, was thus formed.
The articles produced by the method of the present invention as demonstrated in Example 1 are characterized by a marked decrease in interface reflectance, an increase in total transmission, and no significant increase of optical scattering. The reflectivity of the air/substrate interface over the range of wavelengths extending between 400 and 700 nm for a prior art nonstructured CR-39 surface and for the microstructured surface described above is shown in FIG. 2, curves A and B respectively. As can be seen, a dramatic reduction in interface reflectivity resulted, wherein the reflectance is essentially reduced to zero for the 400-520 nm region and does not increase to more than 0.7% for the rest of the wavelength region. In optical elements, it is most often desired to increase the interface transmittance and decrease the specular reflection. In such instances, diffuse reflection is to be avoided. The fact that this is indeed the case for the product of this invention is demonstrated by FIG. 3 in which the transmission for an untreated sheet of CR-39 and the sheet treated as in Example 1 are shown.
Further confirmation of the relative lack of diffuse scattering is shown in FIG. 4, where the intensity of light (HeNe laser at a wavelength of 633 nm) scattered from a given object is plotted semilogarithmically as a function of the angle off the normal. In Curve A of FIG. 4, the intensity of the light without an object in the path of the beam is plotted. Curve B shows the scattering of the light for a prior art control panel of CR-39 in which neither surface had been treated. In contrast, Curve C shows the intensity of light scattered from a CR-39 panel where both surfaces were treated as set forth in Example 1. As may there may be seen, the intensity of light scattered at 5° off the normal is approximately five orders of magnitude below the peak intensity at normal. Curve D shows the result when an undesirable surface microstructure is produced. In this case, the differential sputtering was continued for nine minutes, rather than the 60 seconds as in Example 1, to intentionally produce pyramids larger than the preferred range of this invention. As can be seen, the off-normal scattering is approximately two orders of magnitude greater than that for the preferred article. The microstructured surface thus produced according to the method of this invention provides an interface whose reflectivity is relatively independent of the angle of incidence, similar to microstructured surfaces produced by other means, such as, for example, that disclosed in U.S. Pat. No. 4,114,983 (Maffitt et al).
EXAMPLE 2
A CR-39 polycarbonate plano-convex lens blank was substituted for the planar sample of Example 1. Each surface of the lens blank was microstructured according to the procedure outlined in Example 1, except that the sputter deposition of chromium was continued for three minutes and the sputter etching was continued for 90 seconds, rather than the 60 seconds of Example 1. The topography of each surface was observed to be substantially the same as that of FIG. 1. Since each surface is microstructured, the transmission of an optical beam over a wavelength region of 400-700 nm was very near 100%, with essentially no off axis scattering.
EXAMPLE 3
In this Example, a 10 cm×10 cm×0.2 cm piece of Type 147F pure extruded polymethylmethacrylate sheet from E. I. DuPont Corporation was substituted for the polycarbonate substrates of the previous examples. The sheet was scrubbed clean in mild detergent and water as in Example 1. The sample was rinsed in distilled, deionized and filtered water, and subsequently blown dry with nitrogen gas. Chromium was then sputter deposited on the sample as in Example 1; however, the deposition time was continued for five minutes to provide an average film thickness of about 0.6 nm. Further processing was the same as in Example 1, with the exception that the sputter etch time was about 135 seconds. The air/sample interface produced by this method was characterized by a decrease in interface reflectance, increase in interface transmission and no significant increase of optical scattering, similar to the results as produced in Example 1.
EXAMPLE 4
To show the utility of the method of the invention, using other techniques for depositing the discontinuous microislands, in this Example all the materials, processing steps, etc. were the same as in Example 3, except that the discontinuous chromium metal film was produced by resistive evaporation from a tungsten boat in a vacuum of about 2×10 -5 torr. Using aforementioned Airco Temescal FDC 8000 film deposition controller to control the deposition, an indicated film of about 0.1 nm of chromium was deposited. After sputter etching as before, reflectivity of the air/acrylic interface over the wavelength region 400-700 nm was observed to vary from about 1% to 2.5%. Thus a significantly decreased reflectance, and hence improved transmission, was demonstrated, although it was not quite as dramatic as in the preferred sputter deposited case.
EXAMPLE 5
In this example, both major surfaces of a sheet of 100 μm thick oriented polyester were treated according to the following preferred embodiment of this invention. The surfaces of the polyester were clean as received and thus needed no further cleaning prior to treatment. This sample was treated as in Example 1, except that the discontinuous chromium film was produced by sputter deposition for eight minutes from an evaporated chromium cathode at 0.38 watts/cm 2 in 5-6×10 -3 torr of Ar to produce an average thickness of about 1.0 nm. The composite surface was then sputter etched for 105 seconds at 0.31 watts/cm 2 in 5 to 6μ oxygen. The results of the interface reflection reduction and the attendant transmission increase are shown in FIGS. 5 and 6. In FIG. 5, curve A shows that the total reflectance from both surfaces of an untreated sheet was about 13%, whereas after the surfaces were thus treated (Curve B), the total reflectance was reduced to about 3%. In FIG. 6, the transmission of an untreated sheet is shown in Curve A. In Curve B the transmission of the treated sheet is shown to be significantly increased.
EXAMPLE 6
To show the applicability of the present method using non-metallic materials to provide the discontinuous microislands, in this example microislands of glass were provided. As in Example 5, two major surfaces of a 100 μm thick oriented polyester sheet were treated. The surfaces were clean as received and needed no further cleaning. A discontinuous glass film on the polyester surfaces was produced by sputter deposition for eight minutes from a window glass cathode at 0.38 watts/cm 2 in 6 to 7 μm argon to provide a discontinuous glass film having an average thickness of 0.7 nm. The sputter etching was carried out for 150 seconds at 0.31 watts/cm 2 in 5 to 6μ oxygen. The optical results for this example are shown in FIGS. 7 and 8, wherein FIG. 7, Curve B, shows a total reflectance of about 4% over the visible spectrum for the treated sample, and FIG. 8, Curve B, shows an attendant increase in transmittance.
EXAMPLE 7
The use of other metals, particularly those which readily convert to a metal oxide having a very low sputter etching rate, is shown in this Example. An oriented polyester sheet as in Examples 5 and 6 was coated on one major surface with a discontinuous layer of aluminum by sputter deposition for ten minutes from an aluminum plate at 0.23 watts/cm 2 in 6 ×10 -3 torr of Ar. Under such conditions, Al is deposited at a rate of about 0.1 nm per minute; hence, a discontinuous film having a average thickness of about 1.0 nm was produced. The composite surface was then sputter etched for four minutes at 0.23 watts/cm 2 in 6×10 -3 torr of oxygen. The decrease in reflectance from the treated surface of about 5% and an attendant increase in transmittance of about 4% for the optical wavelength range of 400 to 700 nm was observed.
EXAMPLE 8
The applicability of the present invention to another type polymer and discontinuous film forming material is shown in this Example. Here, a thin, extruded sheet consisting of a layer of an amorphous mixture of 80% terephthalate and 20% isophthalate on an oriented polyester substrate was coated by a 30 second sputter deposition of gold from a gold cathode at 0.38 watts/cm 2 in 6×10 -3 torr of Ar to provide an average film thickness of about 2.8 nm. This surface was then sputter etched for one to three minutes at 0.31 watts/cm 2 in 5 to 6×10 -3 torr of oxygen. The microstructured surface which was produced resulted in a surface reflectance reduction as in previous examples.
EXAMPLE 9
In this Example, a base resin of Cellulose Acetate Butyrate (CAB) with no additives for extruding was extruded into a rough, approximately 250 μm thick, sheet. The sheet was then thermally flattened in a press at 150° C. and 9 kg/cm 2 between chrome plated steel backed plates. The sheet was glass coated by sputter deposition for five minutes from a soft glass cathode in 5 to 6×10 -3 torr of argon at 0.38 watts/cm 2 to provide a discontinuous glass film having an average thickness of about 1.2 nm. The coated surface was then sputter etched for three minutes in 6×10 -3 torr of oxygen at 0.31 watts/cm 2 to form the microstructured surface. An interface reduction in reflectance and increase in transmittance resulted as in the previous examples.
EXAMPLE 10
The applicability of the invention to a layered substrate is shown in this Example in which a 30% solids solution of CAB and 50/50 MEK and toluene was cast onto a CR-39 substrate and allowed to dry at 30° C. in a nitrogen atmosphere. The sample was then treated as in Example 9, except that it was coated with a discontinuous film of chromium about 0.15 nm thick by sputter deposition for 75 seconds from a chromium cathode at 0.38 watts/cm 2 in 6 to 8×10 -3 Torr of Ar. The composite surface was sputter etched for 2.25 minutes at 0.31 watts/cm 2 in 8×10 -3 Torr of oxygen. Again, the surface exhibited a decreased reflectance and increased transmittance as a result of the resultant microstructure.
The utility of the present invention to provide a primed surface exhibiting enhanced adhesion is demonstrated in the following additional examples:
EXAMPLE 11
Two 10×30 cm pieces of 0.762 mm thick Rohm & Haas Brand "Tuffak" polycarbonate film were sputter-etched under the following conditions. Discontinuous microislands of Cr metal were first deposited on the film in an RF diode sputtering apparatus operating at 13.56 MH in an Ar gas plasma. A deposition time of 6 minutes at a power density of 0.4 W/cm 2 was used. This was immediately followed by a reactive etch in an O 2 gas plasma for 2.5 minutes at a power density of 0.32 W/cm 2 to produce a desired microstructure.
One piece of the microstructured polycarbonate film was subjected to an adhesion tape peel test as follows. A 10 cm piece of Scotch brand Magic mending tape was folded over itself for 1/3 of its length. The remaining length of exposed adhesive was firmly adhered to the microstructured polycarbonate surface. The tape was then removed from the surface using a forcible upward motion, resulting in the delamination of the adhesive from the tape backing over the entire impressed microstructured area. No adhesive was delaminated when the same test was performed on the unstructured polycarbonate surface.
The second piece of microstructured polycarbonate was overcoated with an epoxy terminated silane UV polymerizable composition and allowed to cure to provide a hard, abrasion resistant layer. The cured overlayer was scored horizontally and vertically with a minimum of 10 lines/in. over an area at least 2.5 cm 2 (cross-hatching). Scotch® brand Magic transparent tape was then firmly adhered to the scored area. Upon removal of the tape, delamination of the adhesive was observed, with no evidence of removal of the overlayer. The same test applied to a similar overlayer coated onto unstructured polycarbonate film resulted in a 100% removal of the overlayer and no adhesive delamination.
EXAMPLE 12
Two 10 cm×10 cm×0.63 cm pieces of Homalite® type 911 Cr-39 (diallyl glycol carbonate), obtained from SGL Industries, were sputter-etched as in Example 11. In this Example, the Cr deposition time was increased to 7 minutes, and the O 2 etch time reduced to 1.25 minutes. A microstructure resulted.
One piece of CR-39 was submitted to the adhesive tape peel test as in Example 11. The adhesive applied to the microstructured surface was delaminated from the tape backing, whereas it remained on the tape backing when applied to the unstructured surface.
The second piece of microstructured CR-39 was coated with an epoxy terminated silane composition and allowed to cure as in Example 11. The coated surface was then scored and adhesive tape firmly adhered to it as in Example 11. Upon removal of the tape, the adhesive delaminated, and no evidence of removal or peeling of the coating was noticed. Submitting coated, unstructured CR-39 to the same test resulted in 100% coating removal (failure).
EXAMPLE 13
Two 10×30 cm pieces of 0.2 cm type 147F acrylic sheet such as described in Example 3 were sputter-etched as in Example 11, except that in this example, microislands of soft glass were deposited over a period of 5.5 minutes. After sputter etching in O 2 as in Example 11, a microstructure resulted.
One piece of the microstructured acrylic sheet was subjected to the adhesive tape peel test as described in Example 11. The adhesive was delaminated by the microstructure surface but not by the unstructured surface, in a manner identical to the results in Example 11.
The second piece of microstructured acrylic sheet was also coated with an epoxy-terminated silane composition and allowed to cure. The coated surface was then scored and adhesive tape firmly adhered to it as in Example 11. Upon removal of the tape, no evidence of coating removal or peel was noticed. Submitting a similarly coated, unstructured acrylic sheet to the same test resulted in 100% coated removal (failure).
EXAMPLE 14
Two 10×30 cm pieces of 0.10 mm polyester film were sputter-etched as in Example 11, except that in this Example the O 2 etch time was decreased to 1.75 minutes. A microstructure resulted.
One piece of the microstructured polyester film was subjected to the adhesive tape peel test as described in Example 11. The adhesive applied to the microstructured surface was delaminated, while that applied to the unstructured surface was not.
The second piece of microstructured polyester film was coated with the epoxy-terminated silane composition and allowed to cure. The coated surface was then scored and adhesive tape firmly adhered to it as in Example 11. Upon removal of the tape, no evidence of coating removal or peel was noticed. Submitting coated, unstructured polyester film to the same test resulted in 100% coating removal (failure).
EXAMPLE 15
A 0.076 mm film of polyvinylidene fluoride was RF sputter coated with SiO 2 for 6 minutes at 0.38 w/cm 2 in 5μ Ar. Subsequently, the masked film was etched in an RF generated oxygen plasma for 3 minutes at 0.31 w/cm 2 in 5μ 0 2 to provide a microstructured surface. When tested in the same manner as in Example 11, the resulting film surface was found to delaminate the adhesive from Scotch Brand Magic Mending Tape, whereas the same test applied to an untreated sample of the same film resulted in no adhesive delamination.
EXAMPLE 16
0.076 mm films of polyethyleneterephthalate and polybutyleneterephthalate were RF sputter coated with SiO 2 for 6 minutes at 0.38 w/cm 2 in 5μ Ar. The films were then RF sputter etched in an oxygen plasma for 3 minutes at 0.31 w/cm 2 and 5μ O 2 to provide a microstructured surface. When tested as in Example 11, resulting microstructures were found to delaminate the adhesive from adhesive tape, whereas untreated samples would not delaminate the adhesive when identically tested.
EXAMPLE 17
A 2.5 mm thick piece of nylon resin (Monsanto Vydyne RP-260) was RF sputter coated with 6 min. SiO 2 at 0.38 w/cm 2 in 5μ Ar. The film was then RF sputter etched in an oxygen plasma for 3 minutes at 0.31 w/cm 2 and 5μ O 2 to provide a microstructured surface. The resulting surface was tested as before and was found to delaminate adhesive from the adhesive tape, whereas the untreated surface would not.
EXAMPLE 18
A 2.5 mm piece of acrylonitrile-butadienestyrene copolymer was RF sputter coated with 6 minutes SiO 2 at 0.38 w/cm 2 in 5μ Ar. The film was then RF sputter etched in an oxygen plasma for 3 minutes at 0.31 w/cm 2 in 5μ O 2 to provide a microstructured surface. This surface was again found to delaminate the adhesive from the adhesive tape while an untreated sample did not.
EXAMPLE 19
A 2.5 mm piece of a phenylene oxide-based resin (Noryl®) (type PN-235 manufactured by G. E. Corp.) was RF sputter coated with 6 minutes SiO 2 at 0.38 w/cm 2 in 5μ Ar. The sample was then RF sputter etched in an oxygen plasma for 3 minutes at 0.31 w/cm 2 in 5μ O 2 to provide a microstructured surface. As in the preceding examples, the treated surface was found to delaminate adhesive from the adhesive tape while an untreated sample did not.
|
A method is disclosed for producing a micro structure on the surface of an article. The method comprises the steps of depositing a discontinuous coating of a material exhibiting a low rate of sputter etching on a substrate exhibiting a higher rate of sputter etching and differentially sputter etching the composite surface to produce a topography of pyramid-like micropedestals random in height and separation. The articles produced by this method are characterized by both the microstructured surface and by the detectable presence of the material exhibiting the lower rate of sputter etching. The microstructured surface results in the articles having uniform antireflecting properties over a large range of angles of incident light and over an extremely broad range of wavelengths, in which the antireflecting characteristic is obtained without an attendant increase in diffuse scattering. Also, the microstructured surface results in the articles being characterized by a high degree of adherence, such that the treated surface may be considered to be "primed", thereby enabling the application of highly adherent coatings or layers thereon.
| 8
|
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to cutting articles by use of a rotating axially moving tool and more particularly to cutting tools having a work-engaging structure and angled or stepped cutting edges. Still more particularly, the present invention relates to cutting plastic pipe to enable a lateral pipe to be replaced on a Y-connection, a T-connection or a 90° connection.
[0003] 2. Background information
[0004] The prior art discloses various tools and methods for cutting pipe.
[0005] U.S. Pat. No. 3,752, 592 to Fitzgerald, et al., for example, discloses a pipe reamer apparatus particularly for use with plastic pipe and a method of reaming plastic pipe fittings such as elbows or the like.
[0006] U.S. Pat. No. 3,872,748 to Bjalme, el al. discloses a tool for beveling plastic pipe in which the tool is carried in a slide inclined at the bevel angle and fed toward the pipe end as it is rotated about the axis of the pipe.
[0007] U.S. Pat. No. 4,483,222 to Davis discloses a device for removing pipe attached to a fitting includes cutting apparatus for removing the pipe disposed within the fitting. A wrench apparatus is connected to the cutting apparatus for gripping the fitting to prevent its movement when the cutting apparatus is activated. Alternatively, this device may be used as a reaming device which permits radial movement of the cutting blades into engagement with a pipe after the cutting blades have been inserted within the pipe.
[0008] U.S. Pat. No. 4,693,643 to Heyworth discloses a planing device which is operable for progressively planing or cutting the end of a plastic pipe to the desired length, or for reaming out a piece of plastic pipe fixed in a plastic pipe fitting in such a manner that the plastic pipe fitting can be reused. The pipe planing device is portable and is rotated by an electric drill or the like and includes a cylindrical pilot removably supported on radially spaced-apart spider-like cutter arms having cutter blades attached to their outer ends and extending outwardly beyond the cylindrical pilot distance which is equal to the thickness of the plastic pipe to be cut or reamed. The outer circumference of the cylindrical pilot is dimensioned to provide a snug rotatable fit within the end of the plastic pipe to be planed and operates to center the planing device along the longitudinal axis of the plastic pipe.
[0009] U.S. Pat. No. 4,975,001 to Rabo, et al. discloses a plastic pipe reboring tool having an elongated shank, a generally concave-convex cutting head, and changeable guide discs effective for cleaning residue glue and plastic from used plastic pipe and fittings so they can be used over again. The reboring tool is operational with both powered and manual chuck rotating devices and can be used on different sizes of plastic pipe.
[0010] U.S. Pat. No. 5,000,629 to Nygards discloses a self-centering plastic pipe router tool for routing of a sawed-off end of pipe from the interior surface of a salvageable pipe. The router tool is a disk with an axial shank on one side of the disk. A pair of cutting flanges extend radially outwardly and upwardly in the direction of the axial shank form the disk perimeter to form first and second cutting edges. A concentric cylindrical skirt extends downwardly form the disk for axial centering of the router tool within the waste pipe inner diameter. The first cutting edges are sized for routing of the waste pipe and second cutting edges are sized to plane and refinish the interior surface of the salvageable pipe for re-use.
[0011] U.S. Pat. No. 5,401,126 to Norris, et al. discloses a bit usable in combination with a rotatory diver, such as a drill, for extracting a remnant of a cut-off pipe from a pipe socket. The bit comprises a forward portion which is a pilot to keep the bit centered in the remnant and thereby centered in the pipe socket, a forward-facing ring cutter whose inner and outer diameters generally match the inner and out diameters of the pipe remnant being extracted, said ring cutter bing operable to cut and/or scrape the remnant edgewise form the socket, and a forward facing ring scraper operable to stop the bit from excessive penetration into the pipe socket and operable to scrape bonding material remnants form the end face of the pipe coupling.
[0012] In working with plastic pipe, a relatively common procedure involves replacing a lateral line which extends at a Y-connection, a T-connection or 90° connection at a at a main pipe line. This procedure is relatively time and labor intensive and an improved means of carrying this procedure out is needed.
BRIEF SUMMARY OF THE INVENTION
[0013] It is an object of the present invention to provide an improved apparatus and method for replacing a lateral line which extends from a Y-connection, a T-connection or a 90° connection at a main pipe line.
[0014] This and other objects are met by the present invention which is a tool for cutting a plastic pipe comprising a concave guide section having a central aperture. A plunger having a longitudinal axis extends through the central aperture and at least one blade extends in generally radial relation from the central axis inside the lower concave skirt section.
[0015] In another embodiment the present invention is a tool for cutting a plastic pipe comprising a concave guide section comprising a lower skirt comprising an upper generally horizontal member and a lower peripheral wall member. There is an aperture in said upper horizontal member and a tubular section having an upper and a lower terminal end and an interior axial passageway and is positioned at said lower terminal end such that said axial passageway is aligned with the central aperture of the generally horizontal member of the lower skirt section. A plunger comprising an upper rod having an upper and a lower terminal end and a spiring retaining structure adjacent said upper terminal end and is disposed in said axial passageway of the tubular member of the concave guide section in coaxial relation with said tubular member and is positioned such that said upper terminal end is elevated above the upper terminal end of the tubular member. A lower blade retaining structure is formed in which at least one blade having a distal edge extends in a generally radial direction such that said distal edge is positioned in spaced inward relation from the lower peripheral wall member of the concave guide section. A helical spring having an upper terminal end and a lower terminal end and coaxially overlaps the upper rod member and bears against the spring returning structure of the rod member at its upper end and bears against the upper terminal end of tubular member at its lower end.
[0016] Also encompassed by the present invention is a method for replacing a first lateral pipe with a second lateral pipe when the first lateral pipe is connected to a main pipe line by a Y-connection, a T-connection or a 90° connection. In this method the first lateral pipe is cut outwardly from the widened connection socket on the Y-connection, a T-connection or a 90° connection. A tool as is described above is then positioned reality to the widened connection section so that the inner surface of the concave guide section bears against the outer surface of widened lateral connecting section and distal edge of the blade bears against the first lateral pipe section. The plunger is then rotated about it longitudinal axis so that the blade cuts away at least part of the inner first lateral pipe section to form a pipe receiving space adjacent the widened connection socket. A second lateral pipe is then inserted end wise into the pipe receiving space to complete the procedure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present invention is further described with the reference to the accompanying drawings in which:
[0018] [0018]FIG. 1 is a cut-away front elevational view of a preferred embodiment of the pipe cutting tool of the present invention;
[0019] [0019]FIG. 2 is a bottom plan view of the pipe cutting tool shown in FIG. 1;
[0020] [0020]FIG. 3 is a schematic view of a lateral line extending from a main line in which illustrates a first step in a preferred embodiment of the method of the present invention;
[0021] [0021]FIG. 4 shows the pipe arrangement shown in FIG. 3 after attachment of the cutting tool shown in FIG. 1 to illustrate further steps in the preferred embodiment of the method of the present invention;
[0022] [0022]FIG. 5 is a bottom and front perspective view of a bit which may be used in an alternate embodiment of the cutting tool of the present invention;
[0023] [0023]FIG. 6 is a bottom and front perspective view of a guide section which may be used with the bit shown in FIG. 5 in an alternate embodiment of the cutting tool of the present invention;
[0024] [0024]FIG. 7 is a vertical cross-sectional view of an alternate embodiment of the cutting tool of the present invention using the bit shown in FIG. 6 and also show in conjunction with a Y-connection to illustrate a step in the method of the present invention;
[0025] [0025]FIG. 8 is a vertical cross-sectional view of the cutting tool shown in FIG. 7 in use on a Y-connection to show further steps in the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Referring to FIGS. 1 and 2, the cutting tool of the present invention includes a guide section 10 which is made up of a tubular section 12 which has an upper terminal end 14 and a lower terminal end 16 and an axial bore 18 . The guide section 10 also includes a lower skirt section 20 which has a horizontal top made up of radial support members 24 , 26 and 28 with a central apeture 30 .
[0027] The lower skirt section 20 also includes a peripheral wall member 32 which has an inner side 34 and an outer side 36 with a plurality of apetures as at apeture 38 in this peripheral wall member 32 which allows operation of the tool to be monitored. The cutting tool also includes a plunger section 40 which has an upper rod 42 having a longitudinal axis 44 and an upper terminal end 46 and lower terminal end 46 . A pin 50 and washer 52 serve as a retaining member for a helical spring 54 , which is also retained at its lower end by the upper terminal end 14 of tubular member 12 of the guide section 10 . The plunger section 40 also includes a lower central blade support structure 56 from which blades as at blades 58 , 60 and 62 extend radially. These blades have respectively wedge shaped terminal cutting edges 64 , 66 and 68 . Blades 58 and 60 also have respectively upper outwardly extending steps 70 and 72 .
[0028] Referring to FIGS. 3 and 4, the method of using the using the tool described above to replace a lateral pipe extending from a Y-connection or T-connection is described. In these figures there is a Y-connection 76 with a horizontal section 78 having at its opposed ends widened pipe sockets 80 and 82 . Main line pipes 84 and 86 are connected respectively to the Y-connection 76 at the widened pipe sockets 80 and 82 . The Y-connection 76 also includes a lateral section 88 which has a terminal widened pipe socket 90 . A lateral pipe 92 is connected endwise to this widened pipe socket 90 and extends outwardly therefrom. In the first step of the method of this invention the lateral pipe 92 is cut slightly outwardly from the pipe socket 90 as is shown particularly in FIG. 3. Lateral pipe 92 is thereby divided into an inner lateral pipe section 94 which remains attached to the pipe socket 90 and an outer pipe lateral pipe section 96 which is removed. As is shown particularly in FIG. 4, in the next step of the method the tool shown in FIGS. 1 and 2 is positioned on the Y-connection 76 so that the blade edges as at 64 , 66 and 68 bear against the inner lateral pipe section 94 and the inner side 34 of the peripheral wall member 32 bears against the pipe socket 90 . The upper rod 42 of the plunger section 40 is then rotated about its longitudinal axis 44 so that the blades cut or abraid the inner lateral pipe section 94 until some or all of the pipe section 94 is removed so that a pipe receiving space is formed adjacent the pipe socket 90 . A new lateral pipe 92 is then inserted endwise into the pipe socket 90 to finalize the procedure.
[0029] Referring FIG. 5, there is shown a bit 98 which may be used in an alternate embodiment of the pipe cutter of the present invention. This bit 98 includes blades 100 , 102 , 104 , 106 , 108 and 110 . The bit 98 also includes a threaded bore 112 to allow attachment to a rod (not shown) similar to the one shown above. Each blade as, for example, blade 100 includes a lower section 114 which has a cutting edge 1 16 . There is also a lower step cutting edge 118 and an upper section 120 with a cutting edge 122 . Above cutting edge 122 there is an upper step cutting edge 123 .
[0030] Referring to FIG. 6, a guide section 124 which may be used in an alternative preferred embodiment is shown. This guide section 124 has a tubular member 126 with an axial bore 128 and a concave section 130 . This concave section 130 is comprised of a horizontal member 132 with a central aperture 134 and is connected by vertical supports 136 , 138 and a 140 to a lower skirt member 142 .
[0031] Referring to FIGS. 7 and 8, the method of use of the alternative preferred embodiment using the bit 98 shown in FIG. 5 and guide section 124 shown in FIG. 6 is illustrated. Here there is a Y-connection 142 similar to the structure described in FIGS. 3 and 4 which has a lateral section 144 with a widened pipe socket 146 . The first section of lateral pipe 148 which remains after the pipe has been cut in the way described above is fixed endwise in the widened pipe socket 146 . The alternate embodiment of the cutter is shown in FIG. 7 in an initial position axially aligned with widened pipe socket 146 and the first section of lateral pipe 148 . It will be observed that in addition to the features described above in the bit 98 and guide section 124 the tool has a plunger 158 which includes the rod 160 which is fitted with the threaded bore of the bit 98 . In this position a pin 162 which extends through apertures in the tubular section 126 and rod 158 folds the bit 98 in an upper position in the guide section 124 adjacent the horizontal member 132 . After the pin 162 is removed the rod 160 along with the bit 98 is moved forward to engage the first section of the lateral pipe with the blades as at blade 100 at the same time the skirt 140 outwardly engages the widened pipe socket 154 . The rod 160 is rotated about its longitudinal axis so that the blades as at blade 100 cut or abraid the first section of lateral pipe 156 to allow its removal, thus leaving a pipe receiving space adjacent the pipe socket 154 . In particular, it will be seen from FIG. 7 that pipe 148 is cut by cutting edges 116 and 118 . The tool is then removed from the widened pipe socket to allow a second lateral pipe (not shown) to be inserted endwise into the widened pipe socket 154 . It will also be appreciated that it would be possible to increase the inner diameter of a pipe. For example, it will be seen from FIG. 8 that the inner diameter of pipe 146 could be increased by means of cutting edge 123 with support being provided by cutting edge 122 .
[0032] Those skilled in the art will appreciate that the tool and method of its use described above on a Y-connection can easily be adapted to replace a lateral pipe connected to a T-connection or a 90° connection.
[0033] It will be appreciated that a tool and the method of its use has been described which allows for the efficient, quick and cost effective removal of a lateral pipe on a Y-connection, a T-connection or a 90° connection and its replacement with another lateral pipe to that connection.
[0034] In the foregoing description, certain terms have been used for brevity, clearness, and understanding. No unnecessary limitations are to be implied therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed.
[0035] Moreover, the description and illustration of the invention is an example and the invention is not limited to the exact details shown or described.
|
A tool for cutting a plastic pipe comprising a concave guide section having a central aperture; and a plunger having a longitudinal axis extending through the central aperture and at least one blade extending in generally radial relation from the central axis inside the concave guide section.
| 1
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a telephone dialing system for specialized services, more particularly, to such a dialing system which is capable of both interpreting the number dialed and responding to received interrogating tones.
2. Objects of the Invention
There are often situations where control of access to telephone use is desired and may be effected by employment of a password or Personal Identification Number (PIN). A related activity where interactive control of a telephone line is necessary is the requirement to supply an account code over a telephone in order to obtain a service. Typical applications of such arrangements include a system for billing hospital patients or university students for phone use through a home or office telephone bill and an automated telephone ordering system for the purchase of goods and/or services. It is with, respect to a specialized dialing system for such applications, toward which the present invention is directed.
SUMMARY OF THE INVENTION
In accordance with the present invention, an interactive, specialized dialing system for local control of access to a telephone line and for providing encoded information relative to an account of a user comprises memory means for storing program instructions, a microprocessor for directing requests for program instructions from the memory means and for responding to instructions stored in the memory, means for generating command signals, means for interfacing with a standard telephone line, means, responsive to the interface means, for receiving encoded signals in standard form from the line and for decoding the signals and supplying the decoded signals to the microprocessor and means, responsive to the command signals from the microprocessor, for providing encoded signals in standard form to the interface means for transmission on the telephone line. The system is adapted to be operated by a user employing a handset coupled to the telephone line. The system, following interrogation, provides a signal to the telephone line with encoded information related to the account of the user.
The invention also encompasses a method of using such interactive specialized dialing system for providing local control of access to a telephone line such as patient telephone access in a hospital environment comprising the steps of: detecting an incoming dialing tone indicating pick-up of a telephone for readying the system for use; checking the signal of the first digit dialed to determine if it is an inter-LATA call; disconnecting the telephone from the line if the signal from the first digit indicates it is an inter-LATA call; comparing, the signals from the initial digits dialed with stored information representing an exception list of inter-LATA calls and a list of prohibited prefixes; if the dialed area code is on the exception list, sending the dialed number over the telephone line using DTMF signals; if the dialed area code is not on the exception list and is not prohibited, sending a DTMF signal to the dialer to indicate that a password is necessary; comparing signals representing a dialed password with a predetermined, stored password pattern; if there is no match between the dialed password signals and the stored password pattern, forwarding the call by sending DTMF signals representing a stored number to a preselected operator service; if there is a match between the passwords, transmitting the dialed number using DTMF signals over the telephone line; and transmitting, upon request, an account code in DTMF signals corresponding to the dialer's line.
The method aspect of the invention of using such interactive specialized dialing system also includes using such system for automated ordering of products and services over telephone lines comprising the steps of providing and storing information representing the telephone number of a order processing center and a unique identification code, upon an order being placed by a subscriber by dialing a first non-numbered key followed by a number corresponding to the service, requesting a password to be dialed by the subscriber; comparing signals representing a dialed password with a predetermined, stored password pattern; if there is a match between the signals representing a dialed password the stored password pattern, transmitting a further DTMF signal indicating that the code number of the item desired should be entered followed by pressing a second and different non-numbered key; upon entry by the subscriber of the code number and second non-numbered key, storing said number and key information; transmitting the number of the ordering service center in DTMF signals over the phone line; upon receipt of an acceptance DTMF signal from the ordering center, transmitting the identification code of the system and the code for the item ordered by sequential DTMF signals over the phone line; the processing center also being capable of requesting confirmation of the order by the subscriber by voice request.
For a better understanding of the present invention, reference is made to the following description and accompanying drawings while the scope of the invention will be pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of the specialized dialing system of the present invention;
FIGS. 2a-i represents a single flow chart of the hospital telephone dialing service of the present invention; and
FIGS. 3a-g represents a single flow chart of the automated ordering dialing service of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawing, shown there is a specialized dialing system 10 in accordance with the present invention. The heart of the system 10 is a memory 11 for storing program instructions, typically an erasable, programmable read-only memory (EPROM); a Texas Instruments TM2732A-30JL having 4K×8 capacity may be employed. The memory 11 receives signals A 0 -A 7 from the microprocessor 12 which typically are requests for program instructions. The memory provides these instructions over lines D 0 -D 7 to the microprocessor 12, typically a Motorola MC6802P device. Depending on these instructions, the microprocessor 12 provides command signals D 0 '-D 3 ' to a transceiver 13, which produces dual tone multifrequency (DTMF or standard Touch-Tone) signals. The DTMF transceiver 13 is typically a Silicon Systems Inc. SSI 75T2090. The DTMF signals are provided by way of a 600 ohm, 1:1 transformer 14 and latching relay 15 to the telephone line.
The microprocessor 12 may be operated by a user by way of a telephone coupled to the phone line through the specialized dialing system. The dialed signal, also in DTMF form, comes, by way of the transformer 14 and relay 15 to the DTMF transceiver 13 for decoding the DTMF encoded signals and for providing, as an output, signals D 0 "-D 3 " to the microprocessor.
The specialized dialing system 10 may be operated in numerous ways to advantage. The first is an arrangement and method for limiting access to long distance lines from a particular handset and for automatically billing long distance calls from such handset. This is the typical situation in a hospital where patients are to be billed.
Billing hospital patients requires that the system have the ability to differentiate between local and long distance calls, the ability to require a password to make long distance calls, the ability to identify the long distance calls made by each patient, and the ability to change the password for each new patient.
When the patient picks up the telephone to make a call, the DTMF transceiver 13 detects the incoming dial tone and alerts the microprocessor 12. The microprocessor 12 then requests the initial program code from the EPROM 11 and prepares to read data from the DTMF transceiver 13. The transceiver places the binary equivalent of any tones received on the data lines D 0 "-D 3 ".
The first digit dialed is checked to see if it could initiate a toll call (i.e., if it is a "1" or "9"). If it does not match the programmed criteria, the call is assumed to be local and is allowed to proceed normally.
If the first digit indicates a toll call, the microprocessor 12 triggers the latching relay open to disconnect the telephone from the line. All numbers dialed by the user on a telephone handset connected to the line are translated to binary form by the DTMF transceiver 13 and stored by the microprocessor 12 on its own random access memory (RAM) which forms part of the microprocessor chip. After the number is dialed, the system, in particular the microprocessor, compares the initial digits with an exception list of local calls which require an area code (non-toll inter-LATA) and with a list of prohibited prefixes (all stored in the EPROM).
If the area code dialed is on the exception list, the microprocessor causes the latching relay to close to reconnect the line. It then reads the number dialed from the microprocessor RAM and sequentially places these numbers on the pins D 0 '-D 3 ' causing the corresponding tones to be sent over the telephone line (by way of the interface).
If the dialed area code is not on the exception list, the microprocessor 12 will instruct the DTMF transceiver to send a tone indicating that a password must be provided by the user. The number dialed by the user will be translated by the DTMF transceiver and stored by the microprocessor in its RAM. The microprocessor will compare the password entered with the pattern previously established (and stored in the microprocessor's RAM). If the two numbers do not match, the call will be forwarded to a preprogrammed number located in an address of the EPROM such as a preselected operator service. The call will also be forwarded if the user (patient) does not respond with a password within a specified time period or if the number dialed is on the prohibited list.
If the two passwords match, the microprocessor 12 will cause the relay to close to reconnect the line, sequentially read the number dialed from the RAM memory and place these signals across the data lines D 0 '-D 3 ' causing the DTMF transceiver to transmit the corresponding tones over the line. This will connect the user/patient with the designated long distance carrier. By prearrangement with the long distance carrier, the carrier will transmit a tone requesting an account code. The DTMF transceiver will detect this tone and signal the microprocessor. The microprocessor will then instruct the DTMF encoder to transmit the account code (stored in EPROM) corresponding to this particular line. The system 10 then becomes transparent to the user/patient until another call is made. The detailed sequence of the specialized dialing system is presented in flow chart form in FIGS. 2a-i.
Another application for which the system is able to be programmed is an automated ordering system (home shopping service). In this configuration, the system is programmed with the telephone number of an order processing center and a unique identification code. Any person subscribing to this service is provided with a specialized dialer and a list of codes to order various items. The subscriber's name, billing and mailing address are stored in a central ordering computer, maintained by the retailer, along with the identification number of the subscriber's dialer.
When a subscriber wishes to place an order, he or she will dial the "#" (pound) key followed by a number corresponding to the service they wish to order. These tones are translated by the DTMF transceiver 13 and relayed to the microprocessor 12. The microprocessor will then cause the latching relay 15 to open to break the connection to the phone line and the DTMF transceiver 13 to transmit the tone indicating that the password must be entered. The number dialed will be decoded by the DTMF decoder and stored in on-chip RAM by the microprocessor. When the complete password has been entered, the microprocessor will compare the number entered with the previously programmed password.
If the password does not match, or if it is not entered within a specified time period, the microprocessor 12 will instruct the telephone line interface 15 to reconnect the phone line. The caller will then receive a dial tone indicating that the transaction has not been completed.
If the password is entered correctly, the microprocessor 12 will instruct the DTMF transceiver 13 to transmit a second tone indicating that the number of the item desired should be entered followed by an "*" sign. These entries will be translated by the DTMF transceiver 13 and stored by the microprocessor 12 in its RAM (on chip).
The microprocessor 12 will then instruct the DTMF transceiver 13 to transmit the tones corresponding to the phone number of the ordering service center (stored in EPROM 11) sequentially over the telephone line. When the call is completed, the ordering service will transmit a tone which instructs the microprocessor 12 to transmit the auto-dialer's identification code and the code for the item ordered. The microprocessor 12 will request the identification code from the EPROM and the item ordered from its RAM memory and instruct the DTMF transceiver 13 to transmit these numbers sequentially over the line. The processing computer will evaluate these tones and respond with a voice message indicating what was ordered and a request to dial "1" to confirm or "2" to reorder. Once the order is placed and confirmed, the order processing computer will thank the customer for their order with a voice message and disconnect the line.
A detailed flow chart representation of the above description of the automated ordering dialing system is presented in FIGS. 3a-g.
The password in both applications will be programmed by the user. The subscriber will create the password by taking the phone off-hook and turning the key in electro-mechanical security switch 16. This will signal the microprocessor to begin the password entry program.
The microprocessor 12 will instruct the DTMF transceiver to transmit the tone to request password entry. The subscriber will then dial the desired new password followed by the "*" key. The tones generated by the telephone will be translated by the DTMF transceiver 13 and stored in on-chip RAM by the microprocessor 12. The microprocessor 12 will then instruct the DTMF transceiver 13 to again transmit the tone requesting password entry. The user will dial the new password a second time. These tones will be translated by the DTMF decoder 14 and stored in the RAM by the microprocessor 12. After this second entry of the password, the microprocessor will compare the two numbers dialed.
If the two numbers match, the new password will be stored at the RAM location reserved for the system's password. The microprocessor 12 will then instruct the DTMF transceiver to sequentially transmit three tones of ascending pitch to indicate that the new password has been accepted.
If the two entries were not the same, the old password will be maintained and the microprocessor 12 will instruct the DTMF transceiver 13 to transmit three tones descending in pitch. This will signal the user that the new password has not been accepted. The microprocessor 12 will then loop to the beginning of the password entry program and instruct the DTMF transceiver 13 to send the tone requesting a password. This cycle will continue until a new password is accepted or the "key" removed from the electromechanical security switch 16.
This description is based on the assumption that the specialized dialer is built with commercially available integrated circuits. It is also possible that all of the functions could be designed into a custom integrated circuit.
It is also evident that transceiver 13 shown as a single block, could be replaced by two separate blocks, one acting as an encoder (transmitter) and one acting as a decoder (receiver).
While the foregoing description and drawings represent the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the true spirit and scope of the present invention.
|
An interactive, specialized dialing system for local control of access to a telephone line and for providing encoded information relative to an account of a user. The system includes a memory for storing program instructions, a microprocessor for directing requests for program instructions from the memory means and for responding to instructions stored in the memory for generating command signals, an interface device for interfacing with a standard telephone line, a transceiver for receiving encoded signals in standard form from the line and for decoding the signals and supplying the decoded signals to the microprocessor and also responsive to command signals from the microprocessor, for providing encoded signals in standard form to the interface device for transmission on the telephone line. The system is adapted to be interrogated by a user employing a handset coupled to the telephone line.
| 8
|
RELATED APPLICATION DATA
[0001] This patent is related to co-pending U.S. Provisional Patent Application Serial No. 60/335,994, which was filed on Nov. 15, 2001.
FIELD OF THE INVENTION
[0002] The present invention generally relates to valves, and more particularly to a replaceable valve seat ring for fluid flow valves.
BACKGROUND OF THE INVENTION
[0003] Fluid valves are used in a wide range of fluid process and control system applications for controlling various flow parameters of a process fluid. A wide variety of valve types are known and can include, for example, dump valves, control valves, throttling valves, and the like. Similarly, fluid process and control systems are utilized for handling a myriad of different fluid media.
[0004] A typical valve has a fluid inlet coupled through a flow control or orifice region to a fluid outlet. A closure device of some kind is typically provided in the flow control region with a portion that is movable to control fluid flow from the valve inlet to the valve outlet. The movable portion is often a valve plug that can be moved to bear against a corresponding fixed seating surface of the closure device to selectively shut off flow of fluid through the valve. During continued use of such a valve, the seating surface of the closure device inevitably becomes worn or damaged. Inadequate flow shut off of the closure device will result, causing poor performance or failure of the valve. Thus, the valve seating surface must eventually be repaired or replaced, or the entire valve must be replaced to again achieve proper function of the valve.
[0005] In one known example, a valve seat ring has a seating surface and is disposed within a flow control or orifice region of the valve. The seat ring is removable in order to replace the seat ring or to repair the seating surface. This type of removable seat ring has a hex-shaped head extending upward from a top surface of the ring. The hex head is adapted to accept a particular standard size hex socket or wrench for installing or removing the ring. However, the upwardly protruding hex head negatively interferes with fluid flow through the orifice region of the valve, and the technician must have the particular tool size on hand.
[0006] In another known example, a pair of small blind bores formed into the top surface of the seat ring. These bores are adapted to receive two spaced apart prongs of a specialized tool to install or remove the ring. The technician must have access to this specialized tool at all times in order to service this type of valve.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Objects, features, and advantages of the present invention will become apparent upon reading the following description in conjunction with the drawing figures, in which:
[0008] [0008]FIG. 1 is a cross sectional view of one example of a dump valve having a replaceable valve seat ring constructed in accordance with the teachings of the present invention.
[0009] [0009]FIG. 2 is a perspective view of the seat ring of the dump valve shown in FIG. 1
[0010] [0010]FIG. 3 is a top view of the seat ring shown in FIG. 2.
[0011] [0011]FIG. 4 is a side cross sectional view taken along line IV-IV of the seat ring shown in FIG. 3.
[0012] [0012]FIG. 5 is a side cross sectional view taken along line V-V of the seat ring shown in FIG. 3.
[0013] [0013]FIG. 6 is a side cross sectional view of the seat ring as shown in FIG. 4 and having a standard extension of a socket wrench installed in the seat ring for installation or removal from the dump valve shown in FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] A valve seat ring for a fluid valve or the like is disclosed herein that is easily installed, removed, and replaced utilizing conventional hand tools. The disclosed valve seat ring is suitable for many different types of valves. The example set forth herein is described with reference to what is known as a sliding stem type “dump” valve construction. However, the disclosed seat ring is equally well suited for many other types and constructions of valves, such as, for example, control valves, throttling valves, or the like. The present disclosure is not to be limited to any particular type of valve.
[0015] The disclosed seat ring includes a region for accepting a standard size and shape socket wrench extension. The standard socket wrench can be utilized to remove and install a seat ring in the valve as desired. The valve seat ring also provides smooth flow characteristics in conjunction with the tool accepting region.
[0016] Referring now to the drawings, FIG. 1 shows one example in cross section of a sliding stem type dump valve 10 constructed in accordance with the teachings of the present invention. The dump valve 10 has a valve body 12 with a fluid inlet 14 at one end and a fluid outlet 16 at an opposite end. The fluid inlet is in communication with an inlet passageway 18 and the fluid outlet is in communication with an outlet passageway 20 . Each of the inlet and outlet passageways 18 and 20 , respectively, meet generally within the valve body 12 and are in communication with one another through an orifice region 22 .
[0017] The valve 10 has a valve plug 24 coupled to a valve stem 26 at one end. The valve stem 26 is coupled at its opposite end to an actuator (not shown) that can move the valve stem and plug along a longitudinal axis of the stem.
[0018] The valve plug 24 has a seating surface 28 which comes in contact with and bears against a valve seat ring 30 when in a valve closed position. The valve seat ring 30 is installed in the orifice region 22 as is described in greater detail below. During operation of the dump valve 10 , the actuator (not shown) moves the valve stem 26 and valve plug 24 toward and away from a seating surface 32 of the seat ring 30 to close and open, respectively, the dump valve to permit fluid flow from the inlet 14 to the outlet 16 through the passageways.
[0019] In accordance with the teachings of the present invention, the seat ring 30 disclosed in FIG. 1 is removably installed within the orifice region 22 of the valve body 12 . The orifice region 22 has a bore 34 extending between the inlet passageway 18 and the outlet passageway 20 . The bore 34 has female mechanical threads 36 formed axially along and circumferentially around at least a portion of the bore.
[0020] As shown in FIGS. 2 - 5 , the seat ring 30 has a circular cylindrical perimeter or circumferential surface 38 with male threads 40 that correspond to the female threads 36 of the bore 34 . As shown in FIG. 1, the seat ring 30 as installed is threaded into the bore 34 . By rotating the seat ring 30 in one direction relative to the bore 34 , the ring can be installed in the orifice region 22 . By rotating the seat ring in the opposite direction relative to the bore 34 , the seat ring 30 can be removed and replaced.
[0021] As shown in FIGS. 2 and 3, the seat ring 30 defines a flow orifice 42 through the orifice region 22 when installed. Fluid passes through the orifice 42 of the seat ring 30 when the valve plug 24 is in the valve open position spaced from the seating surface 32 of the ring 30 . The disclosed flow orifice 42 of the ring 30 is a circular orifice, although the shape of the orifice can vary according to the needs of a particular valve design and to achieve desired flow characteristics. An inlet end of the orifice 42 corresponds with the seating surface 32 of the ring 30 .
[0022] Further details of the disclosed seat ring 30 constructed in accordance with the teachings of the present invention are described with reference to FIGS. 3 - 5 . The larger diameter portion of the perimeter surface 38 of the seat ring 30 , including the male mechanical threads 40 , is formed as a circular cylinder. The seat ring 30 also has a smaller diameter, necked-down end 44 adjacent the outlet end of the orifice 42 . The necked-down end 44 is received in a corresponding smaller diameter portion 45 of the bore 34 when installed. The purpose of the necked-down end 44 is to properly position the seat ring 30 in the orifice region 22 and to align the seat ring with the smaller diameter portion 45 of the bore 34 . An annular shoulder surface 46 extends between and connects the necked-down end 44 and the perimeter threaded surface 38 of the ring. When installed as shown in FIG. 1, the shoulder surface 46 of the ring 30 bottoms against a corresponding ledge or stop surface 48 within the bore 34 . The shoulder surface seats against the ledge surface to precisely position the installed seat ring 30 in the bore 34 of the valve body 12 .
[0023] Though mechanical threads are disclosed herein as a mechanical engaging device for installing the valve seat, other mechanical means for securing the valve seat in place can also be utilized. For example, a key and way system can also be used where the seat and a part of the orifice region engage with one another by a twist-and-lock motion. Other alternative constructions are also certainly within the spirit and scope of the invention.
[0024] As best illustrated in FIGS. 4 and 5, the flow orifice 42 in this example extends only part way through the thickness or height of the ring 30 . The inlet end of the orifice 42 opens into and communicates with a larger sized tool receptacle or recess 50 . The tool recess 50 is formed into a top surface 52 of the ring to a desired depth. The tool recess 50 in this example terminates at an intermediate surface 54 within the body of the ring 30 . The intermediate surface generally lies in the plane of the inlet end of the flow orifice 42 . The seating surface 32 is formed as a recessed annular surface in the intermediate surface and surrounds the inlet end of the flow orifice 42 .
[0025] In the disclosed example, the tool recess or accepting region 50 is an essentially square opening having four sides 56 a , 56 b , 56 c , and 56 d . The four sides are generally vertically oriented, although the sides can be slightly tapered at a draft angle for casting or forming purposes. In this example, the four sides 56 a - 56 d and the intermediate surface 54 together define the tool recess 50 having a shape that corresponds to a standard socket wrench extension. In one example, a standard three-quarter inch socket extension can be inserted directly into the tool recess for removing or installing the seat ring 30 (see FIG. 6 and the description below). In other examples, the tool recess 50 can be configured to accommodate different sized socket extensions such as a standard half-inch or three-eighths inch extension size. In still other examples, the tool recess 50 can be configured to accommodate a different standard configuration tool head other than a socket extension, such as a TORX head, ALLEN wrench, hex head, or other standard configuration.
[0026] Because the disclosed seat ring 30 requires only a standard socket extension, the seat ring eliminates the need for purchasing, maintaining, and storing a special tool or a particular sized tool for installing or removing the ring. Instead, only a standard socket extension, common to nearly every technician's tool box, is sufficient for installation and removal of the valve seat ring. FIG. 6 illustrates a a standard socket extension 58 including an extension head 60 received in the tool recess 50 of the seat ring 30 .
[0027] Aside from the improved installation and removal aspects of the valve seat ring 30 , the ring also provides substantially improved, smooth fluid flow characteristics. For example, the tool recess 50 only extends part way into the valve seat ring 30 and includes no part or element that protrudes upward from the ring top surface or inward into the flow orifice 42 . This seat ring design is thus a substantial improvement over many prior designs which have a protruding feature adapted for accepting a particular tool configuration, as described above.
[0028] The disclosed seat ring 30 provides improved, smooth fluid flow characteristics for additional reasons as well. As shown in FIGS. 4 and 5, the flow orifice 42 is tapered slightly radially outward moving from the inlet end to the outlet end. The radial outward taper of the orifice 42 can achieve certain flow characteristics through the orifice and can be varied, eliminated, or otherwise altered in order to achieve particular desired flow characteristics. Other alternative flow orifice size, and shape configurations are also within the scope and spirit of the present invention. As one example, the separate and discrete flow orifice 42 can be eliminated and the tool recess 50 can extend the entire depth of the seat ring 30 and act as a full length flow orifice. However, in such an example, the valve plug and tool recess must be configured so as to ensure proper seating of the plug to the valve seat to achieve flow shut off. The contours of the tool recess in such an example can be suitably smooth and gradual so as not to severely affect flow characteristics through the recess.
[0029] In the disclosed example, as best illustrated in FIGS. 4 and 5, the top surface 52 of the seat ring 30 is tapered slightly downward moving from near the perimeter surface 38 toward the sides 56 a - 56 d of the tool recess 50 . The top surface transitions to the side surfaces 56 a - 56 d of the recess at smooth, rounded edges or surfaces 62 . The side surfaces 56 a - 56 d again smoothly transition at smooth, rounded interior bottom corners 64 into the intermediate surface 54 . The sides 56 a - 56 d also transition laterally into one another at smooth, rounded corners 66 . The intermediate surface 54 is also angled or tapered slightly downward moving from the tool recess sides 56 a - 56 d toward the seating surface 32 at the inlet end of the flow orifice 42 . The intermediate surface 54 and the seating surface 32 smoothly transition into the flow orifice 42 . The wall of the orifice 42 , as described above, also tapers radially outward moving toward the necked-down end 44 of the seat ring 30 . All of these smooth and slightly tapered surfaces and smooth corners provide smooth flow paths for fluid passing through the orifice region 22 of the valve 10 . The smooth flow surfaces prevent formation of unstable or turbulent pockets of fluid that can detrimentally affect flow characteristics and performance of the valve.
[0030] The replaceable valve seat ring 30 as disclosed herein permits use of a standard socket wrench or other such standard tool for installation and removal of the seat ring from a valve 10 for repair or replacement when damage to the ring has occurred. In addition, the disclosed seat ring produces much improved fluid flow characteristics both over and through the seat ring as compared to prior known replaceable valve seat designs. As will be evident to those having ordinary skill in the art and as noted above, the tool recess 50 can vary from that disclosed. As a further example, the recess can be a six-sided recess for accepting a tool such as an ALLEN wrench and yet perform adequately as disclosed herein. Other variations to the seat ring are also possible. Although the seat ring disclosed herein can be fabricated from numerous different materials, one preferred material is a sufficiently hard and exceptionally durable material known as Alloy 6.
[0031] Although certain replaceable valve seat rings have been disclosed and described herein in accordance with the teachings of the present invention, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the invention that fairly fall within the scope of permissible equivalents.
|
A replaceable valve seat ring for a valve assembly has an annular ring body and an open flow passage extending through the ring body. A seating surface is provided on the ring body adjacent one end of the flow passage. A tool accepting region of the flow passage is formed concentric with and at least partially along the flow passage. The tool accepting region is adapted to receive a standard tool head therein for installing and removing the valve seat ring.
| 8
|
CROSS-REFERENCES TO RELATED APPLICATIONS
This application is related to the following applications: U.S. patent application Ser. No. 08/145,583 entitled Seismic Construction System for Insulated Wall System; U.S. patent application Ser. No. 08/145,584, entitled Veneer Anchoring System; and, U.S. patent application Ser. No. 08/145,585, entitled Seismic Construction System, all filed concurrently on Nov. 4, 1993.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved surface-mounted veneer anchor for use in conjunction with a seismic construction system having an inner wythe and an outer wythe. More particularly, the invention relates to construction accessory devices for surface mounting veneer anchors and for embedding a continuous wire in the bed joints of the outer wythe. These accessory devices include captive wire formatives with positive interlocking arrangements. The invention is applicable to seismic structures having an outer wythe of brick facing in combination with an inner wythe of masonry block or dry wall construction and with various forms of insulation.
2. Description of the Prior Art
In the past, investigations relating to the effects of various forces, particularly lateral forces, upon brick veneer masonry construction demonstrated the advantages of having a continuous wire embedded in the mortar joint of anchored veneer walls. The seismic aspect of these investigations were referenced in the inventor's prior patent, namely U.S. Pat. No. 4,875,319. Besides earthquake protection, the failure of several high-rise buildings to withstand wind and other lateral forces has resulted in the incorporation of a requirement for continuous wire reinforcement in the Uniform Building Code provisions. The inventor's related Seismiclip® and DW-10-X® products (manufactured by Hohmann & Barnard, Inc., Hauppauge, N.Y. 11788) have become widely accepted in the industry. The use of a continuous wire in masonry veneer walls has also been found to provide protection against problems arising from thermal expansion and contraction and improving the uniformity of the distribution of lateral forces in a structure.
The following patents are believed to be relevant and are disclosed as being known to the inventor hereof:
______________________________________Patent Inventor Issue Date______________________________________3,377,764 Storch 04/16/19684,021,990 Schwalberg 05/10/19774,373,314 Allan 02/15/19834,473,984 Lopez 10/02/19844,598,518 Hohmann 07/08/19864,869,038 Catani 09/26/19894,875,319 Hohmann 10/24/1989______________________________________
It is noted that these devices are generally descriptive of wire-to-wire anchors and wall ties and have various cooperative functional relationships with straight wire runs embedded in the interior and/or exterior wythe. Several of the prior art items are of the pintle and eyelet/loop variety without positive restriction against escape upon vertical displacement.
U.S. Pat. No. 3,377,764--D. Storch--Issued Apr. 16, 1968
Discloses a bent wire, tie-type anchor for embedment in a facing exterior wythe engaging with a loop attached to a straight wire run in a backup interior wythe.
U.S. Pat No. 4,021,990--B. J. Schwalberg--Issued May 10, 1977
Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Like Storch '764, the wall tie is embedded in the exterior wythe and is not attached to a straight wire run.
U.S. Pat. No. 4,373,314--J. A. Allan--Issued Feb. 15, 1983
Discloses a vertical angle iron with one leg adapted for attachment to a stud; and the other having elongated slots to accommodate wall ties. Insulation is applied between projecting vertical legs of adjacent angle irons with slots being spaced away from the stud to avoid the insulation.
U.S. Pat. No. 4,473,984--Lopez--Issued Oct. 2, 1984
Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation.
U.S. Pat. No. 4,598,518--R. Hohmann--Issued Jul. 7 1986
Discloses a dry wall construction system with wallboard attached to the face of studs which, in turn, are attached to an inner masonry wythe. Insulation is disposed between the webs of adjacent studs.
U.S. Pat. No. 4,869,038--M. J. Catani--Issued Sep. 26, 1989
Discloses a veneer wall anchor system having in the interior wythe a truss-type anchor, similar to Hala et al. '226, supra, but with horizontal sheetmetal extensions. The extensions are interlocked with bent wire pintle-type wall ties that are embedded within the exterior wythe.
U.S. Pat. No. 4,879,319--R. Hohmann--Issued Oct. 24, 1989
Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run.
None of the above provide a completely interlocked arrangement between the inner wythe and the outer wythe, such as a brick veneer, and all of the above lack a fixed interconnection as described hereinbelow.
SUMMARY
In general terms, the invention disclosed hereby is a seismic construction system that includes a surface-mounted veneer anchor. The seismic construction system hereof is applicable to construction of a wall having an inner wythe which can either be of dry wall construction or masonry block and an outer wythe and to insulated and non-insulated structures. The wythes are in a spaced apart relationship and form a cavity therebetween. In the disclosed system, a unique combination of a veneer anchor (attachable to either masonry or metal studs), a box tie member, and a facing anchor is provided. The invention contemplates that the primary components of the veneer anchor are wire formatives providing closed loop, wire-to-wire connections therebetween.
In the first embodiment of this invention, the inner wythe is constructed from a masonry block material, the masonry anchor has a baseplate with a wire formative attached thereto having elongated eye wire extensions. The elongated eye wires extend into the cavity between the wythes. Each pair of eye wires accommodates the threading thereonto of a box tie through the open end of the box tie. The box tie is then positioned so that the open end is secured to the facing anchor and is embedded together with the facing anchor into the bed joint thereof. The baseplate of the veneer anchor is surface-mounted onto the masonry block of the interior wythe. The facing anchor includes a seismic clip for accommodating a straight wire run and receiving the open end of the box tie. The facing anchor is embedded in a bed joint of the exterior wythe. As the elongated eye wires have sealed eyelets or loops and the open ends of the box ties are sealed in the joints of the exterior wythes, a positive, closed-loop interengagement results.
In another mode of practicing this invention, the inner wythe is a dry wall construct, the dry-wall anchor, having a stamped metal baseplate, is attached by sheetmetal screws to the metal vertical channel members of the wall. Each dry-wall anchor accommodates in rolled flanges of the baseplate a wire formative having a pair of elongated eye wires. As in the case of the masonry inner wythe, the open end of the box tie is then positioned so that the open end is securable to a seismic clip that is part of the facing anchor. The facing anchor also accommodates one or more straight wire runs The facing anchor is embedded in a joint of the exterior wythe. Because the elongated eyes of the dry-wall anchor are closed loop and the open ends of the box ties are sealed in the joints of the exterior wythes, a positive interengagement results.
In the above, when the technology is applied to insulated structures, the elongated eye portions can be oriented to secure the insulating panels and the insulation can be protected by insulation shields as described hereinbelow.
OBJECT AND FEATURES OF THE INVENTION
It is an object of the present invention to provide in a seismic construction having a facing wythe and a backup wythe, a surface-mounted veneer anchor, a box tie device, and a seismic facing anchor including continuous wire reinforcement in the mortar joint of the facing wythe.
It is another object of the present invention to provide labor-saving devices to aid in seismic-type installations of brick and stone veneer and the securement thereof to an inner wythe.
It is yet another object of the present invention to provide a veneer anchor system which ties together the continuous wire reinforcement in a positive manner such that the connective portion in the cavity between the wythes cannot separate.
It is a further object of the present invention to provide a veneer anchor system comprising a limited number of component parts that are economical of manufacture resulting in a relatively low unit cost.
It is yet another object of the present invention to provide a veneer anchor system which restricts lateral and horizontal movements of the facing wythe with respect to the inner wythe, but is adjustable vertically.
It is a feature of the present invention that the box tie, after being threadedly inserted into a veneer anchor has the open end thereof, embedded in a bed joint of the facing wythe together with the facing anchor.
It is another feature of the present invention that the box tie is utilizable with an elongated eye wire for either a masonry block having aligned or unaligned bed joints or for a dry wall construct that secures to a metal studs.
Other objects and features of the invention will become apparent upon review of the drawings and the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following drawings, the same parts in the various views are afforded the same reference designators.
FIG. 1 is a perspective view of a first embodiment of a seismic construction system, including a surface-mounted veneer anchor, and shows a wall with an inner wythe of masonry block and an outer wythe of brick veneer having the bed joints thereof out of alignment with the veneer anchor;
FIG. 2 is a partial perspective view of FIG. 1 showing details of the veneer anchor, the box tie, the seismic clip, and the reinforcement wire;
FIG. 3 is a cross-sectional view of the box tie and facing anchor of FIG. 2;
FIG. 4 is a perspective view of a second embodiment of a seismic construction system, including a surface-mounted veneer anchor, but shows a wall with an inner wythe of dry wall construction with metal studs and an outer wythe of brick veneer;
FIG. 5 is a partial perspective view of FIG. 4 showing details of the veneer anchor, the box tie, and the facing anchor;
FIG. 6 is a cross-sectional view of the box tie and facing anchor of FIG. 5;
FIG. 7 is a perspective view of a third embodiment of a seismic construction system, including a surface-mounted veneer anchor similar to FIG. 4, but showing a wall with an inner wythe having externally mounted insulation;
FIG. 8 is a partial perspective view of FIG. 7 showing details of the veneer anchor, the box tie, and the facing anchor; and,
FIG. 9 is a cross-sectional view of the box tie and the facing anchor of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 to 3, the first embodiment of a seismic construction system of this invention is shown and is referred to generally by the numeral 10. In this embodiment, a wall structure 12 is shown having an interior wythe 14 of masonry blocks 16 and an exterior wythe 18 of facing brick 20. Between the interior wythe 14 and the exterior wythe 18, a cavity 22 is formed. In the first embodiment, successive bed joints 24 and 26 are formed between courses of blocks 16 and the joints are substantially planar and horizontally disposed. Also, successive bed joints 28 and 30 are formed between courses of bricks 20 and the joints are substantially planar and horizontally disposed. For purposes of discussion, the exterior surface 32 of the interior wythe 14 contains a horizontal line or x-axis 34 and an intersecting vertical line or y-axis 36. A horizontal line or z-axis 38 also passes through the coordinate origin formed by the intersecting x-and y-axes. Further, it will be seen that the various anchor structures are constructed to restrict movement interfacially--wythe vs. wythe--along the z-axis and, in this embodiment, along the y-axis. The system 10 includes a veneer anchor 40 constructed for affixation to masonry blocks 16 and a box tie device 42 that is constructed to interlock with a facing anchor 44, both of which are for embedment in bed joint 28. The veneer anchor 40 is shown in FIG. 1 as being affixed to a course of blocks 16. In the best mode of practicing the invention, a sheetmetal plate or baseplate 46 is formed having a rear surface 48 which, when the baseplate 46 is mounted on the masonry block 16 by an attachment device 50, such as explosive-emplaced fastening device, is coplanar with the exterior surface 32 of masonry blocks 16. Although any of a number of methods may be used to attach the baseplate and the wire formative portion of this surface-mounted veneer anchor, the baseplate 46 hereof is constructed with flanges 52 extending forwardly (when viewed as installed) from at least two sides thereof and being dimensioned to accommodate a wire formative 54 therewithin. A spaced pair of transverse wire member portions 56 are constructed to extend therefrom. These pairs of wire member portions 56 extend into the cavity 22. As will become clear by the description which follows, the spacing therebetween wire member portions 156 limits the x-axis movement of the construct. Each transverse wire member portion 56 has at the end opposite the attachment end an elongated eye wire portion 58 formed continuous therewith. Upon installation, the eye 60 of eye wire portion 58 is constructed to be within a substantially vertical plane (a yz plane) normal to exterior surface 32 and the longitudinal axes 62 of eyes 60 to be within a substantially vertical plane 64 (an xy plane) parallel to exterior surface 32. The spatial relationship between the pair of elongated eyes 60 is constructed so that a box tie device 42 is threadedly emplaceable thereinto by introducing the box tie through the elongated eyes 60 and rotating the box tie device vertically in plane 64. Upon insertion, the box tie device 42 is erectable in a horizontal plane (an xz plane) with the open end dimensioned for embedment in bed joint 28 of brick veneer 20. This relationship minimizes the x- and z-axis movement of the construct. Upon mounting the box tie device 42 in bed joint 28, the closed end 66 thereof is adjustably positionable along axes 62. For positive engagement, the elongated eyes 60 of eye wire portion 58 are sealed forming closed loops. The box tie 42 is a wire formative constructed with a rear or closed end portion 66, a pair of side portions 68 and 70, and a pair of substantially parallel front portions 72 and 74 with an opening or slot therebetween. The longitudinal axes of portions 66, 68, 70.72, and 74 are substantially coplanar. The opening formed between side portions 68 and 70 is slightly larger than the outer horizontal (viewed as installed) dimension of elongated eyes 60, and when the box tie 42 is threadedly emplaced through the eye opening, the spacing just described controls the x-axis movement of the construct. The substantially parallel front portions 72 and 74 are spaced apart sufficiently to engage the facing anchor 44 described hereinbelow. The front portion 72 is contiguous with side portion 68, and front portion 74 is contiguous with side portion 70. The facing anchor 44 is constructed from a reinforcement or straight wire member 76 and a clip member 78. The clip member 78 is an adaptation of the clip member described in U.S. Pat. No. 4,875,319, supra and, like the predecessor, is of unitary construction. The clip member 78 includes a base portion 80 and a plurality of substantially parallel projections 82, 84, 86, 88 and 90 defining a plurality of channels 92, 94, 96, and 98. The spacing between projections is proportioned in a manner such that the two innermost channels accept the front portions 72 and 74 of the box tie device 42. The spacing forming the two outermost channels are dimensioned such that one or more wire members 76 of preselected diameters may be selectively inserted in the appropriate channel. The bottom portion 100 of the clip member 78 has a plurality of parallel grooves 102. These grooves facilitate the bonding of the clip member 78 to the mortar in the bed joints 28 between courses of bricks 20. During the construction of the exterior wythe 18, the mortar also fills the channels of clip member 78 thereby bonding together the clip, the reinforcing wire and the box tie device 42.
The description which follows is of a second embodiment of the dry wall construction system utilizing the surface-mounted veneer anchor technology. For ease of comprehension, where similar parts are used reference designators "100" units higher are employed. Thus, the box tie 142 of the second embodiment is analogous to the box tie 42 of the first embodiment. Referring now to FIGS. 4 to 6, the second embodiment of a dry wall construction system of this invention is shown and is referred to generally by the numeral 110. In this embodiment, a dry wall structure 112 is shown having an interior wythe 114 of wallboard facings 116 and an exterior wythe 118 of facing brick 120. Between the interior wythe 114 and the exterior wythe 118, a cavity 122 is formed. In this embodiment, vertical metal studs 124 with insulating panels 126 therebetween are erected between the interior and exterior wallboard facings 116 and the metals studs 124 have substantially planar are vertically disposed outer surfaces. As in the first embodiment, successive bed joints 128 and 130 are formed between courses of bricks 120 and the joints are substantially planar and horizontally disposed. Sites at a vertical height on metal studs 124 corresponding to bed joint 128 are selected to be substantially coplanar, the one with the other. The extent of vertical misalignment that is tolerated by this system is discussed in greater detail hereinbelow. For purposes of discussion, the exterior surface 132 of the interior wythe 114 contains a horizontal line or x-axis 134 and an intersecting vertical line or y-axis 136. A horizontal line normal to the plane formed thereby or z-axis 138 also passes through the origin formed by the intersecting x- and y-axes. In the discussion which follows, it will be seen that the various anchor structures are constructed to restrict movement interfacially--wythe vs. wythe--along the z-axis and, in this embodiment, along the x-axis. The system 110 includes a surface-mounted veneer anchor 140 constructed for affixation to metal studs 124 and a box tie device 142 that is constructed to interlock with a facing anchor 144, both of which are for embedment in bed joint 128. The veneer anchor 140 is shown in FIGS. 5 and 6 as being affixed to a metal stud 124. In the best mode of practicing the invention, a sheetmetal plate or baseplate 146 is formed having a rear surface 148 which, when the baseplate 146 is mounted to the metal stud 124 by an attachment device 150, such as a self-tapping screw fastening device, inserted through aperture 151. The baseplate 146 is constructed with flanges 152 extending forwardly (when viewed as installed) from at least two sides thereof and being dimensioned to accommodate a wire formative 154 therewithin. In the second embodiment, the geometry of the baseplate 146 is distinguished from the generally rectangular baseplate 46, as shown for the first embodiment. Here, the baseplate is basically triangular with the flanges on adjacent sides rather than on opposite sides. A spaced pair of transverse wire member portions 156 are constructed to extend therefrom. These pairs of wire member portions 156 extend into the cavity 122. As will become clear by the description which follows, the spacing between wire member portions 156 limits the x-axis movement of the construct. Each transverse wire member portion 156 has at the end opposite the attachment end an elongated eye wire portion 158 formed continuous therewith. Upon installation, the eye 160 of eye wire portion 158 is constructed to be within a substantially vertical plane (a yz plane) normal to exterior surface 132 and the longitudinal axes 162 of eyes 160 to be within a substantially vertical plane 164 (an xy plane) parallel to exterior surface 132. The spatial relationship between the pair of elongated eyes 160 is constructed so that a box tie device 142 is threadedly emplaceable thereinto by introducing the box tie through the elongated eyes 160 and rotating the box tie device vertically in plane 164. Upon insertion the box tie device 142 is erectable in a horizontal plane (an xz plane) with the open end dimensioned for embedment in bed joint 130 of brick veneer 120. This relationship minimizes the x- and z-axis movement of the construct. For positive engagement, the elongated eyes 160 of eye wire portion 158 are sealed forming closed loops. The box tie 142 is a wire formative constructed with a rear portion 166, a pair of side portions 168 and 170, and a pair of substantially parallel front portions 172 and 174 with an opening or slot therebetween. The longitudinal axes of portions 166, 168, 170. 172, and 174 are substantially coplanar. The opening formed between side portions 168 and 170 is slightly larger than the outer horizontal (viewed as installed) dimension of a pair of elongated eyes 160, and when the box tie 142 is threadedly emplaced through the eye opening, the spacing just described controls the x-axis movement of the construct. The substantially parallel front portions 172 and 174 are spaced apart sufficiently to house therebetween reinforcement member 144. The front portion 172 is contiguous with side portion 168, and front portion 174 is contiguous with side portion 170. The facing anchor 144 is constructed from a reinforcement or straight wire member 176 and a clip member 178. The clip member 178 is an adaptation of the clip member described in U.S. Pat. No. 4,875,319, supra, and, like the predecessor, is of unitary construction. The clip member 178 includes a base portion 180 and a plurality of substantially parallel projections 182, 184, 186, 188, and 190 defining a plurality of channels 192, 194, 196, and 198. The spacing between projections is proportioned in a manner such that the two innermost channels accept the front portions 172 and 174 of the box tie device 142. The spacing forming the two outermost channels are dimensioned such that one or more straight wire members 176 of preselected diameters may be selectively inserted in the appropriate channel. The bottom portion 200 of the clip member 178 has a plurality of parallel grooves 202. These grooves facilitate the bonding of the clip member 178 to the mortar in the bed joints 28 between courses of bricks 120. During the construction of the exterior wythe 118, the mortar also fills the channels of clip member 178 thereby bonding together the clip, the reinforcing wire and the box tie device 142.
Referring now to FIGS. 7 to 9, the third embodiment of the masonry construction system is shown and is referred to generally by the numeral 210. The dry wall structure 212 is shown having an interior wythe 214 with wallboards 216 as the interior and exterior facings thereof. An exterior wythe 218 of facing brick 220 is attached to dry wall structure 212 and a cavity 222 is formed therebetween. The dry wall structure 212 is constructed to include, besides the wallboard facings 216, vertical studs or channels 224, insulation layer 226 disposed on the exterior face of exterior wallboard 216. The insulation layer 226 is commonly applied in horizontal strips having horizontal seams 227 between abutting strips. Selected bed joints 228 and 230 are constructed to be in cooperative functional relationship with the surface-mounted veneer anchor described in more detail below. For purposes of discussion, the exterior surface 232 of the interior wythe 214 contains a horizontal line or x-axis 234 and an intersecting vertical line or y-axis 236. A horizontal line normal to the plane formed thereby or z-axis 238 also passes through the origin formed by the intersecting x- and y-axes. The system 210 includes a surface-mounted veneer anchor 240 constructed for attachment to vertical channel members or metal studs 224, a facing anchor 242 constructed for embedment in joint 228 and an interconnecting wall tie member 244. These components 240, 242, and 244 are shown in FIGS. 8 and 9 and are interconnected with one another and affixed to a metal stud 224. In the best mode of practicing the invention, a sheetmetal plate or baseplate 246 is formed having a rear surface 248 which, when the baseplate 246 is mounted to the metal stud 224 by an attachment device 250, such as a self-tapping screw fastening device, inserted through aperture 251. The baseplate 246 is constructed with flanges 252 extending forwardly (when viewed as installed) from at least two sides thereof and being dimensioned to accommodate a wire formative 254 therewithin. In this embodiment, the geometry of the baseplate 246 is similar to that of generally rectangular baseplate 46, as shown for the first embodiment. A spaced pair of transverse wire member portions 256 are constructed to extend therefrom. These pairs of wire member portions 256 extend over the insulation 226 into the cavity 222. As will become clear by the description which follows, the spacing between wire member portions 256 limits the x-axis movement of the construct. Each transverse wire member portion 256 has at the end opposite the attachment end an elongated eye wire portion 258 formed continuous therewith. With the externally applied horizontal strip-type insulation, the eye wire portions 258 are constructed to depend, when installed, downwardly from the transverse wire portion 256 and together with insulation shield 259 hold the insulation 226 in place. Upon installation, the eye 260 of eye wire portion 258 is constructed to be within a substantially vertical plane (a yz plane) normal to exterior surface 232 and the longitudinal axes 262 of eyes 260 to be within a substantially vertical plane 264 (an xy plane) parallel to exterior surface 232. The spatial relationship between the pair of elongated eyes 260 is constructed so that a box tie device 242 is threadedly emplaceable thereinto by introducing the box tie through the elongated eyes 260 and rotating the box tie device vertically in plane 264. Upon insertion the box tie device 242 is erectable in a horizontal plane (an xz plane) with the open end dimensioned for embedment in bed joint 230 of brick veneer 220. This relationship minimizes the x-and z-axis movement of the construct. For positive engagement, the elongated eyes 260 of eye wire portion 258 are sealed forming closed loops. The box tie 242 is a wire formative constructed with a rear portion 266, a pair of side portions 268 and 270, and a pair of substantially parallel front portions 272 and 274. The longitudinal axes of portions 266, 268, 270. 272, and 274 are substantially coplanar. The opening formed between side portions 268 and 270 is slightly larger than the outer horizontal (viewed as installed) dimension of a pair of elongated eyes 260, and when the box tie 242 is threadedly emplaced through the eye opening, the spacing just described controls the x-axis movement of the construct. The substantially parallel front portions 272 and 274 are spaced apart sufficiently to house therebetween reinforcement member 244. The front portion 272 is contiguous with side portion 268, and front portion 274 is contiguous with side portion 270. The facing anchor 244 is constructed from a reinforcement or straight wire member 276 and a clip member 278. The clip member 278 is an adaptation of the clip member described in U.S. Pat. No. 4,875,319, supra, and, like the predecessor, is of unitary construction. The clip member 278 includes a base portion 280 and a plurality of substantially parallel projections 282, 284, 286, 288, and 290 defining a plurality of channels 292, 294, 296 and 298. The spacing between projections is proportioned in a manner such that the two innermost channels accept the front portions 272 and 274 of the box tie device 242. The spacing forming the two outermost channels are dimensioned such that one or more straight wire member 276 of preselected diameters may be selectively inserted in the appropriate channel. The bottom portion 300 of the clip member 278 has a plurality of parallel grooves 302. These grooves facilitate the bonding of the clip member 278 to the mortar in the bed joints 228 between courses of bricks 220. During the construction of the exterior wythe 218, the mortar also fills the channels of clip member 278 thereby bonding together the clip, the reinforcing wire and the box tie device. In the drawings, an optional insulation retaining plate 304 is shown, and is constructed to fit over a pair of transverse wire members 256 with the channel 306 securing the plate in position. The plate 304 fits against the rear portion of elongated eyes 260 of eye wire portions 258 and spreads the force of the eye wire portions 258 over the area of the plate. The deformation of the insulation pieces along the edge retained by the eye wire is thereby minimized.
Although the foregoing description suggests planar box ties 42, 142 and 242, it is within the contemplation of the present invention that a bent box tie is applicable. Also, although all of the box ties are rectangular, other geometric shapes could function satisfactorily. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
|
A seismic construction system is disclosed that includes a surface-mounted veneer anchor, a box tie member, and a facing anchor. The primary components of the veneer anchor is a wire formative providing closed loop, wire-to-wire connections between the formative and the box tie device. The veneer anchor has a baseplate with a wire formative attached thereto having elongated eye wire extensions. Each pair of eye wires accommodates the threading thereonto of a box tie through the open end of the box tie. The box tie is then positioned so that the open end is secured to the facing anchor and is embedded together with the facing anchor into the bed joint thereof. The facing anchor includes a seismic clip for accommodating a straight wire run and receiving the open end of the box tie. The facing anchor is embedded in a bed joint of the facing. As the elongated eye wires have sealed eyelets or loops and the open ends of the box ties are sealed in the joints of the exterior wythes, a positive, closed-loop interengagement results. In insulated structures, the elongated eye portions is oriented to secure the insulating panels and the insulation are protected by insulation shields.
| 4
|
Priority to German Patent Application No. 102 33 491, filed Jul. 24, 2002, and to U.S. Provisional Patent Application No. 60/399,581, filed Jul. 30, 2002, is hereby claimed. Both of these applications are hereby incorporated by reference herein.
BACKROUND INFORMATION
The present invention relates to a device for imaging a printing form, including a number of light sources as well as imaging optics for producing a number of image spots of the light sources on the printing form, the imaging optics including at least one macro-optical system of refractive optical components.
In order to pattern printing forms, in particular printing plates, into ink-accepting and ink-repelling regions, the printing form surface, which is initially in an unpatterned, for example, ink-accepting state, is often partially exposed to the influence of electromagnetic radiation, in particular heat or light of different wavelengths, so as to produce the other, for example, ink-repelling state at the affected positions. To image a printing form selectively, accurately and rapidly, a number of individually addressable light sources, in particular laser light sources, that are arranged in an array in rows or in the form of a matrix are often used in parallel operation, the light sources being projected through imaging optics onto the surface of the printing form, which is located in the image field of the imaging optics.
In this context, a number of requirements for the fulfillment of various functionalities are placed on an imaging optical system in such a device for imaging a printing form, whether in a printing form imaging unit or in a printing unit. First of all, a part of the imaging optics is intended for globally projecting the number of light sources to image spots with as few imaging defects as possible. This part for projecting a plurality of light sources together to image spots is herein defined as “macro-optics” or “macro-optical system”. Secondly, further parts of the imaging optics or parts of the macro-optics itself can fulfill additional functionalities, such as a possibility of adjusting the focus position.
Frequently, the light source arrays are composed of a certain number of individually addressable diode lasers, preferably single-mode diode lasers, which are arranged on a semiconductor substrate at certain intervals, typically at equal, i.e. substantially equal, intervals, and which have a common output plane that is precisely defined by the crystal fracture plane (IAB, individually addressable bar). Since the light-emission cones of these diode lasers have different opening widths in the two essentially orthogonal planes of symmetry, there is a need for optical correction to reduce the asymmetric divergence of the emerging light. The ratio of opening angles can be adjusted individually. This correction is carried out with respect to the individual light sources using a part of the imaging optics that is also referred to as “micro-optics”.
A number of imaging optics which were designed especially for projecting diode laser rows in order to image an image carrier are known from the prior art. For example, U.S. Pat. No. 4,428,647 describes an imaging device including a semiconductor laser array whose individual lasers each have associated therewith a nearby lens for correcting divergence. The light of the semiconductor lasers is then collected by an objective lens and focused onto an image carrier. An imaging device having an individually addressable diode laser array is known from European Patent Application No. EP 0 878 773 A2. The imaging optics has a micro-optical part and a macro-optical parts. The macro-optical part is a confocal lens arrangement that is telecentric on both sides. Prior German Patent Application No. DE 101 15 875.0 describes an imaging device having an array of light sources. The imaging optics includes micro-optics which produces virtual intermediate images of the light sources as well as macro-optics which contains a convex mirror and a concave mirror having a common center of curvature, a combination of the so-called “open type” and which produces a real image of the virtual intermediate images.
The approaches known from the prior art have in common that they require a large installation space compared to their functionalities. Modification or complementation with further functionalities can only be achieved with difficulty. Since, first of all, the installation space in such machines is very limited and, secondly, the design or configuration of the printing form imaging unit or of the printing unit can be modified only slightly for implementing an imaging device, it is necessary to reduce the installation space requirement without limiting the necessary functionalities. Moreover, an imaging optical system on a printing press or on a printing form imaging unit is subject to shocks or vibrations, which is why optical systems known from the prior art can generally not easily be transferred for use on a printing form imaging unit or inside a printing unit of a printing press.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a compact device for imaging a printing form which allows easy integration into the available installation space in a printing unit of a printing press.
According to the present invention, a device for imaging a printing form has a number of light sources as well as imaging optics for producing a number of image spots of the light sources on the printing form. The imaging optics includes at least one macro-optical system of refractive optical components or optical elements, in particular, a number of lenses, which is traversed twice by the optical path from the light sources to the image spots. In the context of this description, the word “optical path” is understood to mean all the optical paths of the number of light sources. In particular, the refractive optical components are passed through twice. It is the refractive optical components that substantially contribute to the generation of the number of image spots. Since the optical path passes through the macro-optics multiple times or repeatedly, the macro-optics can have a more compact and installation-space saving design compared to macro-optics having a simple optical path, while maintaining the same functionality. The number of light sources can also be 1; preferably, however, provision is made for a plurality of light sources. The light sources can be arranged in a one-dimensional array (line, preferred) or in a two-dimensional array, in particular in a regular array, preferably in a Cartesian arrangement. The light sources and the image spots are in a one-to-one functional relationship with each other. The image spots are disjunct from each other. It is possible for the image spots to be dense or, preferably, not to be dense with respect to each other; that is, their spacing can be greater than the minimum spacing of the printing dots to be placed. The spacing of neighboring image spots on the printing form in units of the minimum printing dot spacing is preferably a natural number that is relatively prime to the number of image spots (light sources). The printing form is preferably an offset printing form.
In this context, the optical path can run non-centrally through the macro-optics. In particular, the optical path can be different on the first path through the macro-optics than on the second path through the macro-optics. Moreover, the optical path can run symmetrically to the optical axis of the macro-optics. In particular, the first path can run symmetrically to the second path.
The double passage of the optical path through the macro-optics can be such that the first principal plane and the second principal plane of the macro-optics are located on one side of the macro-optics. The macro-optics can be designed in such a manner that objects (a number of light sources) and images are located on one side of the macro-optics. In other words, the optical path passes through the macro-optics on a first path in a first direction and on the second path in a direction opposite to the first direction.
In an advantageous embodiment of the device for imaging a printing form, at least one mirror, in particular a plane mirror, is associated with the macro-optics. The macro-optics can be designed in such a manner that the optical path passes through the macro-optics in a first direction on its first path until the light hits the at least one mirror, whereupon it passes through the macro-optics in a direction opposite to the first direction on its second path. The macro-optics is virtually equal to an optical system of double the size. In other words, a macro-optical system composed of a number of optical elements is optically doubled in size or doubled by the mirror or mirrors; the mirror or mirrors reflecting the light into a symmetrical second passage through the macro-optics.
In a device according to the present invention for imaging a printing form, the macro-optics can include at least one part that is designed as an adaptive optic, or at least one of the associated mirrors can be designed to be adaptive. In particular, at least one of the associated mirrors can be designed as an adaptive mirror, i.e., with a variable radius of curvature or with a variable surface structure. By varying the radius of curvature, it is possible to change the image width. A variation of the radius of curvature is small compared to the dimensions of the adaptive mirror. The adaptive mirror can also enable the wavefront of the light to be manipulated on the optical path through the macro-optics, for example, to achieve an axial change in focusing/defocusing. The adaptive mirror can be an adjustable element for compensating imaging defects. An adaptive mirror can be a membrane mirror, an electrostatic mirror, a bimorph mirror, a piezoelectrically driven (for example, polish-milled) metal mirror, or the like.
In an advantageous embodiment of the device according to the present invention for imaging a printing form, the macro-optics can include at least one movable lens, or, alternatively, a movable mirror. The movable lens is preferred, in particular because the telecentricity of macro-optics is maintained although the lens is moved. When the printing form or printing plate is clamped to a cylinder, the attachment often causes a disturbing curvature (“plate bubble”), which can be on the order of several 100 micrometers. Due to the curvature, it is possible for the printing form surface to come to rest outside the usable focal range of the laser radiation so that the power density of the laser radiation at such a distance from the focus position is not sufficient to achieve an acceptable imaging result. A movable lens in the macro-optic makes it possible for the focus position of the laser radiation to be moved (refocused) in the direction of the optical axis in a simple manner. The accuracy requirements for this refocusing result from the depth of focus of the laser beams. The device according to the present invention allows easy integration of the functionality of focus displacement. The device has a defined distance between the last optical component and the printing form, the distance remaining unchanged by the focus displacement. At the same time, it is possible to obtain a good ratio between the displacement of the movable lens and the focus position variation.
In an advantageous embodiment of the device for imaging a printing form, the light sources are individually addressable lasers. Each light source corresponds to an individually addressable imaging channel having one imaging beam. In particular, the light sources can emit in the infrared (preferred), visible, or ultraviolet spectral ranges. In an advantageous refinement, the lasers can be tunable and/or operated in pulsed mode in the nanosecond, picosecond, or femtosecond regime. The individually addressable lasers can be, in particular, diode lasers or solid lasers. The individually addressable lasers can be integrated on one or more bars, which, in particular, can be one or more individually addressable bars (IAB), preferably single-mode. A typical IAB includes 4 to 1,000 lasers, in particular, 30 to 260 lasers. The lasers are located on the IAB preferably at substantially equal intervals, in particular in a line (one-dimensional array) or on a grid (two-dimensional array).
In the device according to the present invention for imaging a printing form, a micro-optical system can be arranged downstream of the number of light sources along the optical path, the micro-optics being arranged upstream of the macro-optics along the optical path. For diode lasers, in particular on a bar, the micro-optics can be used, inter alia, for adjusting the beam diameters. Due to the very small diameters of the individual laser beams at the front of the IAB, typically a few micrometers in the horizontal direction (slow axis) and a few micrometers in the vertical direction (fast axis), the beam diameters need to be adjusted in both axes independently of each other in order to achieve the diameters needed on the printing form, typically a few micrometers in the horizontal or vertical directions. The aim is to obtain fundamental mode Gaussian laser beams that are as ideal as possible, because these have the greatest natural depth of focus and, thus, are maximally insensitive to shifts in focus or “plate bubbles”. The lasers are preferably operated in single mode. A micro-optics can be arranged downstream of the individually addressable lasers, allowing the beam diameters of the light beams emerging from the lasers to be influenced in two orthogonal axes independently of each other, i.e. to be adjusted independently of each other. The image spots of the micro-optics (intermediate image) can be real or virtual. In particular, the micro-optics can be produce a virtual, enlarged intermediate image of the number of light sources that is projected by the macro-optics.
In the device according to the present invention for imaging a printing form, it is particularly advantageous if the light of the number of light sources is coupled into the macro-optics via at least one light-deflecting element. This measure makes it possible to make the design even more compact. As an alternative to a mirror pair, it is possible and preferred to use a Porro prism as the light-deflecting element to couple the light of the number of light sources into the macro-optics. Using a Porro prism, it is also possible to adjust the optical path through the macro-optics.
In an advantageous embodiment, the macro-optics of the device according to the present invention is telecentric on both sides. In this connection, it should be pointed out that during focusing, for example, using an adaptive mirror or a movable lens in the macro-optics of the device according to the present invention, the telecentricity is maintained. In other words, the object-to-image distance is changed by the focus displacement described in detail above, while the object distance is fixed. Using an optical path that is telecentric over the whole extent, it is achieved that the size of the image is not changed or changed only within very small tolerances of typically ±1 micrometers in the directions orthogonal to the beam propagation (optical axis). Moreover, the macro-optics can advantageously be designed to allow imaging essentially without changing the size, i.e. 1:1 imaging. The focal length of the macro-optics is preferably infinite.
In an advantageous embodiment of the device according to the present invention, correction optics for adjusting the image size can be arranged downstream of the macro-optics along the optical path. The correction optics permits very high positional accuracy of the image spots and preferably also a very accurate adjustment of the image size. Preferably, the correction optics is a zoom lens system of two lenses. The zoom lens system itself is telecentric on both sides, just as the macro-optics. The telecentricity is maintained during adjustment of the image size.
In an advantageous embodiment of the device according to the present invention, neighboring image spots of the number of image spots of the light sources on the printing form can have a substantially equal distance a, i.e. equal distance a, which is a whole-number multiple of minimum printing dot spacing p. In particular, the number of light sources can advantageously be n, with n being relatively prime to the number (a/p), so that a non-redundant interleaving method can be carried out for imaging the printing form. Obviously, n and (a/p) are not both 1 simultaneously.
In a preferred embodiment of the device according to the present invention for imaging a printing form, the printing form to be imaged can be mounted on a rotatable cylinder. Alternatively, the surface of a rotatable cylinder can constitute a printing form. In other words, the printing form can be a plate-shaped printing form (having one edge) or a sleeve-shaped printing form (having two edges). It can be a (conventional) printing form that can be written once, a recoatable or a rewritable printing form. In the context of this description of the device according to the present invention, “printing form” is understood to include also a so-called “digital printing form”. A digital printing form is a surface that is used as an intermediate carrier for printing ink before this printing ink is transferred to a printing substrate. In this context, the surface itself can be patterned into ink-accepting and ink-repelling regions, or only be provided with printing ink in a patterned manner through imaging. Interaction with laser radiation allows the digital printing form to be patterned into regions which do or do not deliver the printing ink to a printing substrate or to an intermediate carrier. The patterning of the digital printing form can be carried out prior or subsequent to applying ink to the printing form. The printing form can also be essentially composed of the printing ink itself, for example, for use in a thermal transfer method.
The imaging device according to the present invention can be used especially advantageously in a printing form imaging unit or in a printing unit of a printing press. A printing unit can contain one or more imaging devices. A plurality of devices can be arranged in such a manner that they can concurrently image partial areas of a printing form. A printing press according to the present invention, which features one or more inventive printing units can be a web-fed or sheet-fed press. A sheet-fed press can typically include a feeder, a delivery, and one or more finishing stations, such as a varnishing unit or a dryer. A web-fed printing press can have a folding apparatus arranged downstream. The underlying printing method of the inventive printing unit or of the inventive printing press can be a direct or indirect planographic printing method, a flexographic printing method, an offset printing method, a digital printing method, or the like.
Also related to the inventive idea is a method for changing the relative position of an image spot with respect to the position of a printing form in a device for imaging a printing form, including a number of light sources as well as imaging optics for producing a number of image spots of the light sources on the printing form, the imaging optics including at least one macro-optical system. The method according to the present invention has the feature that a lens of the macro-optics that is traversed twice by the optical path is moved. When using macro-optics which is traversed twice by the optical path, the object-to-image distance can be changed by moving a lens in the macro-optics, while the object distance is fixed. Advantageously, the telecentricity is maintained. The method according to the present invention can preferably be carried out using a device for imaging a printing form, such as is described in this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages as well as expedient embodiments and refinements of the present invention will be depicted by way of the following Figures and the descriptions thereof. Specifically,
FIG. 1 shows a preferred embodiment of the imaging optics of the device according to the present invention for imaging a printing form;
FIG. 2 shows a preferred embodiment of the micro-optics of the device according to the present invention for imaging a printing form, with Subfigure A in the vertical plane and Subfigure B in the horizontal plane;
FIG. 3 is a schematic representation of an advantageous embodiment of the device according to the present invention for imaging a printing form on a printing form cylinder; and
FIG. 4 is a schematic representation of an advantageous embodiment of the device according to the present invention for imaging a printing form in a printing unit of a printing press.
DETAILED DESCRIPTION
FIG. 1 shows a preferred embodiment of the imaging optics of the device according to the present invention for imaging a printing form. Along optical path 22 , starting at the number of light sources 14 , in a preferred embodiment an individually addressable diode laser bar (IAB), imaging optics 18 includes micro-optics 34 , a Porro prism 48 , macro-optics 20 , i.e. a lens system producing a 1:1 image, and correction optics 50 . Imaging optics 18 produces a number of image spots 16 of the number of light sources 14 . At the top left of FIG. 1 , a scale in millimeters is added for quantitative purposes.
Using micro-optics 34 , the beam diameters can be influenced independently of each other in the two orthogonal directions perpendicular to the propagation direction (optical axis). The micro-optics makes it possible to adjust the size of the spots to be imaged. FIG. 2 serves to illustrate in more detail micro-optics 34 , which includes a fast-axis lens 36 and a slow-axis lens 38 . The number of light sources 14 and micro-optics 34 can also be enclosed in a common housing. Porro prism 48 , or alternatively two mirrors, is used to couple the light into the multiple-lens 1:1 lens system of macro-optics 20 and to align the beams in the image plane. Inner surfaces of Porro prism 48 serve as light-deflecting elements 46 through total reflection. Macro-optics 20 includes a first lens 56 , a second lens 58 , a third lens 60 , a fourth lens 62 , a fifth lens 64 , a movable lens 32 (the moving direction is indicated by the double arrow), and a mirror 30 . The lenses of the macro-optics and mirror 30 are arranged axisymmetrically around the optical axis 24 . Optical axis 22 does not run along optical axis 24 , but non-centrally or off-axis. Using mirror 30 , which is preferably provided with a highly reflective coating, the light is reflected and passes through micro-optics 20 again; however, in such a manner that it is symmetrically mirrored on optical axis 24 with respect to the first path. In other words, optical path 22 runs through macro-optics 20 such that it is folded. First principal plane 26 and second principal plane 28 of the macro-optics are located on one side of macro-optics 20 , in particular, symmetrically. In the preferred embodiment shown in FIG. 1 , a Porro prism 48 is arranged upstream of macro-optics 20 . In consequence, spots of mirrored principal plane 27 , in which are located light sources 14 , are imaged onto second principal plane 28 of macro-optics 20 . To adjust the focus position of image spots 16 , the object-to-image distance of macro-optics 20 , which is traversed twice by the optical path, is changed in a controlled manner. In this embodiment, this is done by moving movable lens 32 . Due to the double passage and the suitable design of macro-optics 20 , a good ratio between the displacement of movable lens 32 and the change in the focus position of image spots 16 is achieved; a displacement by s results in a change by m*s, with m>>1. The optical path through macro-optics 20 is telecentric. In the embodiment shown in FIG. 1 , telecentric correction optics 50 including a first lens 52 and a second lens 54 is arranged downstream of macro-optics 20 for fine correction. Correction optics 50 is a two-lens zoom lens system which allows stepless adjustment of the image size in a range of plus or minus a few percent, approximately from 0.9 to 1.1.
FIG. 2 shows a preferred embodiment of the micro-optics of the device according to the present invention for imaging a printing form. Subfigure A shows a view in the vertical plane in vertical direction 42 and with horizontal direction 40 out of the plane of paper, while Subfigure B shows a view in the horizontal plane in horizontal direction 40 and with vertical direction 42 into the plane of paper. At the top left of FIGS. 2A and 2B , a scale in millimeters is added for quantitative purposes. In a preferred embodiment, micro-optics 34 is composed of a fast-axis lens 36 and a slow-axis lens 38 . Fast-axis lens 36 is a glass fiber which is polished on one side and reduces the divergence of all beams of the number of light sources 14 in the fast axis thereof. Slow-axis lens 38 is an array of a number of cylindrical lenses whose number corresponds to the number of light sources, each individual lens reducing the divergence of the beams of the light source 14 that is associated with the lens. Micro-optics 34 is designed in such a manner that a virtual intermediate image 44 is produced.
FIG. 3 relates to a schematic representation of an advantageous embodiment of the device according to the present invention for imaging a printing form on a printing form cylinder. FIG. 3 shows a device for imaging 10 a printing form 12 which is mounted on a printing form cylinder 66 . The beams of a number of light sources 14 , here individually addressable diode lasers on a bar, are shaped by micro-optics 34 and subsequently coupled a into macro-optics 20 having a mirror 30 via a Porro prism 48 . Optical path 22 passes through macro-optics 20 twice and then passes through correction optics 50 . Light sources 14 are projected onto image spots 16 on printing form 12 . A triangulation sensor 68 is integrated for determining the position of printing form 12 compared to the focus position of the imaging optics of the imaging device 10 . Sensor light 70 is reflected at the surface of printing form 12 , so that it is possible to determine the distance. The surface of the printing form can have marked curvatures on the order of several 100 micrometers (“plate bubbles”) so that the focus position is changed using movable lens 32 . Triangulation sensor 68 can make a measurement at a point of printing form 12 which is reached in the image field of image spots 16 only at a later time by rotation of printing form cylinder 66 in direction of rotation 80 . This point can also be offset from image spot 16 along the axis of printing form cylinder 66 . The number of light sources 14 is connected to a laser driver 72 which is operatively connected to a control unit 74 .
FIG. 4 shows a schematic representation of an advantageous embodiment of the device according to the present invention for imaging a printing form in a printing unit of a printing press. In a printing unit 88 of a printing press 90 , an imaging device 10 according to the present invention is associated with a printing form 12 on a printing form cylinder 66 . By way of example, three imaging beams 76 produce three image spots 16 in an image field 82 on printing form 72 . Printing form cylinder 66 is rotatable about its axis 78 in direction of rotation 80 ; imaging device 10 is movable in direction of translation 86 parallel to axis 78 . The unfolding line running through image spots 16 is preferably oriented substantially parallel to axis 78 of printing form cylinder 66 . Printing dots are produced on printing form 12 by image spots 16 which are passed over the two-dimensional surface of printing form 12 along helical paths 84 (helices) through the interaction of the rotation of printing form cylinder 66 and the translation of imaging device 10 .
The advance in direction of translation 86 and the rotation in direction of rotation 80 are preferably coordinated in such a manner that printing form 12 is traversed in a non-redundant manner, but in such a way that it is possible to place dense printing dots. In order to pass a number of imaging beams 76 (independently of whether they are arranged on one or on several imaging devices) in a non-redundant manner over the locations of a two-dimensional surface of a printing form 12 on which printing dots are to be placed by image spots 16 , it is required to observe certain advance rules for the passage of positions (locations) that are imaged in a preceding step with respect to positions (locations) that are imaged in a subsequent step. These advance rules must be strictly complied with, especially if in an imaging step, n imaging beams 76 place n printing dots at positions (locations) which are not dense on printing form 12 , i.e., whose distance is not the minimum printing dot spacing p (typically 10 micrometers). When looking at an azimuth angle of the printing form, then dense imaging can be achieved if printing dots are placed between already imaged printing dots in a subsequent imaging step. This procedure is also known by the term “interleaving method” (interleaving). An interleaving method for imaging a printing form is characterized, for example, U.S. Patent Publication No. US2002/0005890A1, the disclosure of which is incorporated herein by reference. For a given minimum printing dot spacing p, for a row of n imaging channels on an unfolding line which are equally spaced and whose neighboring image spots on the printing form have a distance a which is a multiple of minimum printing dot spacing p, a non-redundant advance by a distance (np) in the direction of the unfolding line is ensured when n and (a/p) are relatively prime. The observance of an interleave advance rule results in interleaved helical paths 84 of the image spots. Along the unfolding line of an azimuth angle, image spots 16 are placed on helical paths 84 between image spots 16 of other helical paths 84 , which were already placed at a previous point in time. In a printing unit 88 according to the present invention, a printing form 12 is imaged using imaging device 10 according to the present invention, preferably in an interleaving method, in particular in the interleaving method described in U.S. Patent Publication No. 2002/0005890 A1.
List of Reference Numerals
10 imaging device 12 printing form 14 number of light sources 16 image spot 18 imaging optics 20 macro-optics 22 optical path 24 optical axis 26 first principal plane 27 mirrored principal plane 28 second principal plane 30 mirror 32 movable lens 34 micro-optics 36 fast-axis lens 38 slow-axis lens 40 horizontal direction 42 vertical direction 44 virtual intermediate image 46 light-deflecting element 48 Porro prism 50 correction optics 52 first lens of the correction optics 54 second lens of the correction optics 56 first lens of the macro-optics 58 second lens of the macro-optics 60 third lens of the macro-optics 62 fourth lens of the macro-optics 64 fifth lens of the macro-optics 66 printing form cylinder 68 triangulation sensor 70 sensor light 72 laser driver 74 control unit 76 imaging beam 78 axis of the printing form cylinder 80 direction of rotation 82 image field 84 path of the image spots 86 direction of translation 88 printing unit 90 printing press
|
A compact device for imaging ( 10 ) a printing form ( 12 ), including a number of light sources ( 14 ) as well as imaging optics ( 18 ) for producing a number of image spots ( 16 ) of the light sources ( 14 ) on the printing form ( 12 ), the imaging optics ( 18 ) including at least one macro-optical system ( 20 ) of refractive optical components ( 32, 56, 58; 60, 62, 64 ), the imaging device having the feature that the optical path ( 22 ) from the light sources ( 14 ) to the image spots ( 16 ) passes through the macro-optics ( 20 ) twice. The installation-space saving imaging device ( 10 ) can be used in a printing unit ( 88 ) of a printing press ( 90 ).
| 1
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/168,245 filed Dec. 1, 1999 and is a continuation in part of U.S. patent application Ser. No. 09/155,781 filed Oct. 2, 1998, which is the national phase in the United States of International Patent Application Serial No. PCT/US97/04050 filed Mar. 12, 1997, which claims the benefit of U.S. Provisional Patent Application Serial No. 60/016,852 filed May 3, 1996.
BACKGROUND OF THE INVENTION
1 Field of the Invention
This invention relates to powder metallurgy, and in particular to the application of powder metallurgy to produce precisely repositionable components.
2. Discussion of the Prior Art
International Patent Publication No. WO 97/42424 published Nov. 13, 1997, which is hereby incorporated by reference, discloses an integral dowel design solution for a problem where there was a specific need for bearing caps to be accurately repositioned after joint separation and reassembly. U.S. patent application Ser. No. 09/155,781 filed Oct. 2, 1998, which issued Jul. 11, 2000 as U.S. Pat. No. 6,086,258, hereby incorporated by reference, is the national phase in the United States of International Patent Application Serial No. PCT/US97/04050 filed Mar. 12, 1997 which was published in the above identified International Publication No. WO 97/42424.
The essential function of a bearing cap is to retain and locate a rotary shaft, or a bearing for a rotary shaft which in turn retains and locates the shaft, relative to a support structure. For example, the main bearing cap of an engine bolts to a bulkhead of the engine crankcase and together with the bulkhead retains and locates the crankshaft journal in place while the crankshaft is rotating. The crankshaft journal runs against two half shell bearings which are fitted to the main bearing cap and the engine bulkhead semi-circular bores, respectively.
In this case, for vibration free, low friction and quiet running, the roundness of the bore produced by the main bearing cap and the bulkhead is very important. This roundness is achieved by a machining operation called line boring. The main bearing caps are bolted to the bulkheads of the engine block, and then a boring bar fitted with a cutting tool is used to machine the bores in the assembly. This ensures the two half rounds formed by the main bearing cap and the bearing block form as near to a perfect circle as possible. A finishing operation involving a grinding hone is often used to achieve the extremely fine tolerances needed for quiet running and efficient engine performance.
However, to install the crankshaft, it is necessary to remove the main bearing caps from the engine block. After the crankshaft is put in place, it is necessary to reposition the main bearing caps to the bulkhead so that they are replaced in the identical position they occupied during the line boring operation. Any deviation from that original position produces an out-of-round condition that, in turn, leads to vibration, noise and possibly stiff, high friction crankshaft operation.
There are a number of conventional structures for re-locating and attaching the main bearing caps to bulkheads when installing the crankshaft. One such structure is shown in FIG. 1 . In this instance, the main bearing cap C has a very precisely machined, snap-width W, which is the distance across the long axis of the main bearing cap across the foot sections T of the bearing cap. Similarly, a precision channel P is machined in the engine block bulkhead B to produce a controlled interference fit with the feet T when the main bearing cap C is refitted after crankshaft installation.
This method does not, however, provide relocation in the fore and aft direction (i.e., in the direction of the axis of the journal bore J). The bolt holes H themselves are used to control the axial repositioning, and since there is a substantial clearance between the bolts F and the bolt holes H of the main bearing cap C, this relocation accuracy is generally poor.
In addition, the interference fit between the main bearings caps C and the channel P in the engine block B in this structure is a variable which affects the final roundness of the bore J after re-installation. A highly stressed main bearing cap C may stress relieve during engine operation, thereby changing the roundness of the bore. Also, the precision machining operations required on the main bearing caps C to define the snap width W and on the block B to form the channel P, so as to avoid an overstressed or loose main bearing cap in this structure, are relatively expensive.
Another known method of location and attachment is shown in FIG. 2 . This involves the use of hollow dowels D. These dowels D are pressed into counter-based holes L in the engine block bulkhead B. The dowels D then locate in precisely machined counterbores M in the corresponding main bearing cap foot sections T. The accuracy of installation of the hollow dowels D is dependent upon the precision counterboring of the engine block and the main bearing cap. Both of these operations have a finite tolerance which, when stacked up with the tolerance on the dowel D outer diameter, can produce an unacceptable variation in location of the main bearing cap C. Additionally, this procedure has the added expense of purchasing precision hollow dowels, their handling and installation, and the costly machining of precision bores L in the bulkhead B and M in the main bearing caps C.
In many cases where hollow dowels as shown in FIG. 2 are used, the engine block channel/main bearing cap snap width relocation method of FIG. 1 is also used. This combination is expensive and, in fact, can produce a situation where the interference fits between the snap-width and channel are in conflict with the interference fits between the hollow dowels and the main bearing cap or bulkhead holes.
It has also become clear that there are many other applications that would benefit from an integral dowel design. One example concerns the need for precise angular location of a toothed sensor ring that measures the timing of an internal combustion engine. FIGS. 27 and 28 show drawings of a portion of the sensor ring and the flywheel or other component to which it is assembled. The previous design of FIGS. 27 and 28 used bolts 601 with a conical head shape that locates into a similar cone shape in a ring 602 . This suffers from the problem of using the threaded hole 603 to provide angular location. As stated above, it is well known in the engineering profession that using a threaded hole to both fix and precisely locate two components is not good practice. The reasons are that it is difficult to thread a hole concentrically, and even harder to ensure that the bolt is concentric to the threads.
This stack-up of errors reduces the precision of the fixture to the point where a separate locating dowel 604 is often needed, as illustrated in FIGS. 28 a-d, similar to the separate dowel of FIG. 2 . As stated above, the two components must be precisely oriented and clamped, then a precision hole 605 must be bored through one component into the second one. Finally, a separate dowel 604 must be pushed through both holes 605 to achieve the desired location precision. This is expensive both in cost of machining and the purchase of the dowel 604 .
SUMMARY OF THE INVENTION
The present invention provides a structure and method of permitting precise repositioning of two components relative to one another where one of the components is made by powder metallurgy (P/M). The P/M component has an integral boss protruding from it, which is received in a bore of the part to which the component is assembled. The boss is of a shape and ductility so that at least one of the boss and bore plastically conform to one another when they are brought together with force, for example in a pressing operation or when they are bolted together for the first time. The plastic deformation of the boss and bore creates a unique mating surface fit between the two parts so that when the two parts are taken apart and then put back together, they go back together in the exact same, or near to the exact same, position.
In a preferred form, the boss is provided around a bolt hole in the P/M component, and the boss fits into a counterbore of a bolt hole in the part to which the P/M component is assembled. Counterboring bolt holes is a standard process in manufacturing and so the invention is readily adapted to be used without major production line changes.
The boss is preferably tapered, so as to progressively tighten in the bore as it is forced in. A lead-in radius maybe provided on a leading edge of the boss to help initially locate the boss in the bore. Axial splines may be provided on the outside of the boss to further contribute to unique plastic deformation between the boss and bore, with the splines and boss conforming to the bore if the bore is in a relatively hard material such as cast iron, or bite into the bore if the bore is in a relatively soft material such as an aluminum alloy.
Plastic conformance between the bore and the boss is facilitated by the boss and remainder of the bearing cap being sintered powder metal, which is not fully dense. However, it may also need to be ductile, depending on the material of the bore, and if so it is preferably a liquid phase sintering powder metal material. Such a material preferably is a powder metal alloy of iron containing phosphorus from ferrophosphorus powder with a phosphorus content of 0.4 to 0.7% and a carbon content of 0 to 0.8%. Additional strength may be achieved with the addition of copper in the amount of 0 to 4% without loss of ductility.
In another preferred aspect, a moat is formed around a trailing end of the boss. The moat creates a void into which material around the bore may bulge or expand when it is deformed by the insertion of the boss.
In another aspect, the boss may be oblong in one direction, so as to provide an interference fit with the bore in that direction. Other means may be provided to accurately position the components in the other direction.
These aspects may be applied to any of a number of different components. Component applications specifically described are main bearing cap, timing sensor ring and connecting rod bearing cap applications, but the invention is not limited to only these applications.
In another aspect of the invention, a deformable boss can be formed on a powder metal insert for casting which acts as a crush ring to seal molten casting metal from flowing into a hole or crevice which the boss surrounds. The insert is placed in the casting mold, and when the mold halves come together, the bosses are crushed so as to form the seal.
In a method of the invention, two parts, one of which is sintered powder metal, are brought together with enough force to cause plastic conformance between the boss of the P/M part and the hole into which it is inserted. The parts are taken apart and, when reassembled, go back together to replicate the original assembled position.
Other objects and advantages of the invention will be apparent from the detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a prior art main bearing cap secured to an engine bulkhead;
FIG. 2 is a cross-sectional view of another prior art main bearing cap secured to an engine bulkhead;
FIG. 3 is a side elevation view of a main bearing cap incorporating the invention;
FIG. 4 is a bottom plan view of the main bearing cap of FIG. 3;
FIG. 5 is a fragmentary detail side elevation view of a foot of the main bearing cap of FIGS. 3 and 4;
FIG. 6 is a fragmentary bottom plan view of the foot of FIG. 5;
FIG. 7 is a view similar to FIG. 5 but of an alternate embodiment;
FIG. 8 is a bottom plan view of the foot of FIG. 7;
FIG. 9 is an enlarged fragmentary detail bottom plan view of the foot of FIG. 8;
FIG. 10 is a partial cross-sectional view as viewed from the plane of the line 10 — 10 of FIG. 9;
FIG. 11 is a partial cross-sectional view as viewed from the plane of the line 11 — 11 of FIG. 9;
FIG. 12 is a partial cross-sectional view as viewed from the plane of the line 12 — 12 of FIG. 11;
FIG. 13 is a partial cross-sectional view as viewed from the plane of the line 13 — 13 of FIG. 11;
FIG. 14 is a view similar to FIG. 5 but of another alternate embodiment of a foot for a bearing cap of the invention;
FIG. 15 is a bottom plan view of the foot of FIG. 14;
FIG. 16 is a view similar to FIG. 5 but of another alternate embodiment of a foot for a bearing cap of the invention;
FIG. 17 is a bottom plan view of the foot of FIG. 16;
FIG. 18 is a view similar to FIG. 5 but of another alternate embodiment of a foot for a bearing cap of the invention;
FIG. 19 is a bottom plan view of the foot of FIG. 18;
FIG. 20 is a side elevation view of another alternate embodiment of a bearing cap of the invention, similar to FIG. 3;
FIG. 21 is a bottom plan view of the bearing cap of FIG. 20;
FIG. 22 is a detail bottom plan view of the left foot shown in FIGS. 20 and 21;
FIG. 23 is a detail side elevation view of the foot shown in FIG. 22;
FIG. 24 is a view of how a bearing cap can be loaded in operation;
FIG. 25 is a bottom plan view of another alternate embodiment of a bearing cap of the invention; and
FIG. 26 is a bottom plan view of another alternate embodiment of the invention.
FIGS. 27 a and 27 b are cross-sectional views of a prior art method of fastening and locating two components relative to one another using a threaded bore in one of the components, a conical counterbore in the other component and a conical headed threaded fastener;
FIGS. 28 a-d are cross-sectional views of a prior art method of fastening and locating two components relative to one another using a separate dowel fitted in holes bored in both components;
FIGS. 29 a and 29 b are cross-sectional views, similar to FIGS. 27 and 28, but illustrating an application of the present invention to joining and locating the two components relative to one another;
FIGS. 30 a and 30 b are cross-sectional views illustrating an application of the present invention to securing and locating a bearing cap relative to a connecting rod;
FIGS. 31 a- 4 are cross-sectional views illustrating an application of the present invention to securing and locating a die casting mold insert in a die casting mold; and
FIGS. 32 a-d are detail views illustrating how an integrally formed crush ring of the insert of FIG. 31 is crushed to seal off the bolt hole from the flow of casting metal.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 3 and 4 illustrate a main bearing cap 10 of the invention. The cap 10 defines a semicircular bore 12 which together with the semicircular bore of the engine bulkhead (see, for example, FIG. 2) defines the bore J (FIG. 2) through which the crankshaft of the engine extends and is journaled. Journal bearings may be received in the bore between the surface of tie crankshaft and the surface of the bore J, as is well known. Cap 10 may be notched as at 14 to receive an ear of the journal bearings so as to prevent the journal bearings from rotating relative to the cap 10 and bulkhead B. The semicircular bore 12 extends through the bearing cap 10 from the front side 16 to the rear side 18 .
The bore 12 defines on each of its lateral sides a foot portion 22 of the cap 10 . A bridge portion 24 joins the two foot portions 22 . A bolt hole 26 extends through each foot portion 22 from the top side 32 to the bottom 34 of the cap 10 . The cap 10 may also be provided with threaded set screw holes 36 extending from the lateral sides 38 and 39 at right angles into the respective bolt holes 26 so as to lock the retaining bolts (F in FIG. 2) in position after the cap 10 is bolted to the engine bulkhead (B in FIG. 2) support structure.
Projecting from the bottom side 34 of each foot 22 around the respective bolt hole 26 is a boss 40 . Each bolt hole 26 extends through its corresponding boss 40 . FIGS. 5 and 6 show in detail the structure of the boss 40 . The two bosses 40 are identical, so only one will be described in detail.
The boss 40 extends for 360° around the bolt hole 26 and is itself surrounded by a recess or moat 44 which is formed in the bottom surface 34 of the foot 22 for the purpose described below.
The bolt hole 26 extends into the engine bulkhead B where it is threaded so that bolts F, as shown in FIG. 2, may be used to secure the cap 10 to the bulkhead B. The bulkhead bolt holes are also counterbored, as shown at L in FIG. 2, so as to receive the bosses 40 in the counterbores of the bulkhead. However, the counterbores L of the bulkhead need not be as precise in diameter or position as was necessary when using the precision hollow dowels D as shown in FIG. 2, because the boss 40 is tapered and the boss 40 and counterbore L are conformable to one another.
To effect perfect mating of the parts during line boring and subsequently thereafter when the crankshaft is installed, the main bearing cap 10 is made by sintered powder metallurgy, with the bosses 40 molded integrally with the feet 22 and remainder of the bearing cap 10 . As shown in FIGS. 5 and 6, the boss 40 tapers from a minor diameter at its leading edge 46 to a larger, major diameter at its trailing edge 48 . The minor diameter is chosen to be less than the diameter of the counterbore L in the bulkhead B, and the major diameter is chosen to be equal to or slightly greater than the diameter of the counterbore L. This tapering of the boss 40 ensures that the main bearing cap 10 is in the identical position after crankshaft installation as it was when it was line bored. The angle of the taper is preferably greater than 7° so as to ensure easy removal of the bearing cap 10 from the bulkhead after line boring.
An alternate embodiment of the boss 40 , designated 140 , is shown in FIGS. 7 and 8, with details shown in FIGS. 9-13. The boss 140 is identical to the boss 40 , except as shown and described below. The boss 140 shown in FIGS. 7 and 8 has linear splines 160 angularly spaced apart all the way around its circumference. Leading edge 146 of the boss 140 defines the minor diameter of the boss 140 , which is less than the diameter of the counterbore in the bulkhead into which the boss 140 fits, and the boss 140 tapers to its major diameter at its trailing edge 148 , which is somewhat greater than the counterbore diameter into which the boss fits.
As shown in FIGS. 9-13, the linear splines 160 are flat from leading edge 146 to line 162 , which is at approximately the axial midpoint of the boss 140 , and are pointed and continue to taper outwardly at a more shallow angle from the midpoint 162 to the trailing edge 148 . The underlying tubular body 164 of the boss 140 may also taper from leading edge 146 to midpoint 162 and may at that point become constant in diameter to the trailing edge 148 so as to provide adequate support to the splines 160 .
FIGS. 14-19 show other alternate embodiments of the invention. Elements corresponding to elements of the boss 140 are labeled with the same reference numeral plus 100 for FIGS. 14 and 15, plus 200 for FIGS. 16 and 17 and plus 300 for FIGS. 18 and 19.
The boss 240 shown in FIGS. 14 and 15 is identical to the boss 140 , except that it is not provided with axially running linear splines 160 . The boss 340 shown in FIGS. 16 and 17 is identical to the boss 40 of FIGS. 3-6, except that it does not extend for 360° around the bolt hole 26 . The moat 344 is also coterminous with the trailing edge 348 of the boss 340 . The boss 440 is the same as the boss 40 , except that it is provided with ribs or axially running linear splines 460 which are flat from their leading edges to their trailing edges.
The exact design of the boss used for practicing the invention will depend upon the application. There must be sufficient conformance between the bosses 40 and the counterbores L of the supporting structure so as to precisely locate the bearing cap 10 relative to the support structure. If additional conformance is needed, a design utilizing the linear splines such as 160 or 460 may be used. The combination of these linear splines and the fact that the sintered powder metal is not fully dense, results in the needed conformance between the boss and the corresponding bulkhead counterbore.
Where the bulkhead material is an aluminum alloy, for example, the linear splines bite into the softer counterbore to make a perfect fit. Any bulging of the aluminum is accommodated by the moat 44 , 144 , 244 , 344 , or 444 . In the case of a cast iron bulkhead, which is relatively hard and non-conforming, the splines can condense and conform to the cast iron counterbore, and, again, form a perfect fit.
FIGS. 20-23 illustrate another alternate embodiment of a bearing cap of the invention. Elements corresponding to elements of the boss 140 are labeled with the same reference numeral plus 400 .
The boss 540 is tie same as tie boss 140 , except that it is oblong (which includes oval), having its longer dimension in the direction of the crankshaft which is retained by the bearing cap, i.e., in the axial direction of the bore 412 . The result is that the bosses 540 engage their round engine block bulkhead counterbores in such a way as to prevent relative motion in the axial direction but provide a clearance in the lateral direction, which is the direction that the snap width (between surfaces 438 and 439 ) provides for location. Thereby, by the oblong bosses 540 providing an interference fit in the axial direction and the snap width providing an interference fit in the lateral direction, the bearing cap 410 is accurately located in all directions.
Since the boss 540 is oblong, the recess or moat 544 , which has a round outer periphery, varies in width as illustrated. The hole 526 is a truncated round shape, having its round shape truncated by laterally extending flats which are spaced far enough apart in the axial direction to permit passage of the bolt F for securing the cap 510 . This shape allows substantial clearance with the bolts in the lateral direction.
In FIGS. 20 and 21, a 360° boss 540 is shown on the left side and a boss 540 is shown on the right which extends for less than 360°, extending for approximately 270° with its inward most quadrant absent. The moat 544 of the right boss 540 is also truncated. It should be understood that the bosses can be different as shown, or can be the same, with both being 360° or 270° bosses.
The precise installation of the main bearing cap 10 , 110 , 210 , 310 , 410 or 510 with any of the bosses described above can be achieved by tightening the retaining bolts F alone, or alternatively, by applying independent pressure to the assembly, for example, from a hydraulic ram. After line boring, the bearing cap is readily removed due to the tapered geometry of the installation interface. After installing the crankshaft, the bearing caps are replaced, and the integral bosses nest into their preformed positions (preformed when the cap was initially mounted to the support structure prior to line boring) with great accuracy.
As stated above, the particular design of the boss will depend on the application. The principal variables in the design are the taper angle, the length of the boss, the relative lengths of the tapered and straight portions of the boss, the number, width, and radial height of any vertical splines, and the radial wall thickness of the boss. The leading edge of the splines may be tapered at a higher angle as shown in FIG. 10 or may have a small lead-in radius as shown in FIG. 18 to aid in initial location of the bearing cap bosses into the bulkhead counterbores. The particular design of a bearing cap incorporating the invention will depend upon various specific design details of the bulkhead, such as whether a bearing notch is needed in the cap, wall thicknesses needed between the bolt hole and the side of the bearing cap, the material of the bulkhead, and the design of the bulkhead counterbore hole, for example, with respect to lead-in chamfers or even a preformed taper. In all cases, however, it is essential that the sintered powder metal bearing cap boss produce a mating surface to ensure identical relocation after installation of the crankshaft, by plastically conforming to the counterbore, causing the counterbore to plastically conform to the boss, or a combination of both.
As mentioned above, for practicing the invention, the bearing cap must be made sintered powder metal. A desirable quality of the power metal material of the bearing cap for carrying out the invention is ductility. Since the splines, or the body in some cases, will yield plastically to some extent during the initial installation process, it is important to avoid cracking. Most powder metal ferrous materials are inherently brittle. To overcome this potential difficulty, it is preferable to use a material that has an adequate ductility.
There are a number of ways of improving the ductility of sintered powder metal ferrous materials, but most of them are expensive or inapplicable to bearing caps. However, an appropriate liquid phase sintering system is particularly useful in providing the necessary ductility in this application. An example of this process involves the use of a phosphorus compound such as ferrophosphorus. A small amount of ferrophosphorus powder is added to the ferrous material powder during powder blending. After compaction and during the thermal treatment stage (sintering), this small amount of ferrophosphorus becomes molten and dramatically increases the rate of atomic diffusion during the sintering process. This enhanced diffusion produces a rounding of the microporosity in the sintered powder metal component which, in turn, provides increased ductility.
To achieve this, the composition of the powder metal material from which the bearing cap of the invention is made should contain 0.4 to 0.7% phosphorus (preferably 0.4 to 0.6% phosphorus), a carbon content of 0 to 0.8% carbon (preferably 0.4 to 0.6% carbon) and with the balance being essentially iron (neglecting impurities). This material with the preferred percentages can produce a tensile elongation of 3%, which is adequate for straight spline conformance to a cast iron counterbore, and also strong enough to indent a cast aluminum alloy bulkhead. Additional strength can be attained by the addition of 0 to 4% copper in the final mix of the material for making bearing caps of the invention without loss of ductility.
In practicing the invention, it is important to ensure dimensional consistency of the distance between the axial centers of the bosses. It is relatively inexpensive to control the counterbore L diameter hole centers in the engine block bulklhead by the use of appropriate drill guides or computer controlled drill heads. However, to control the distance between the boss centers of bearing caps of the invention requires some form of dimensional control during or after the sintering operation. One example of an appropriate procedure is to repress the bearing cap in a set of tools which will straighten and adjust the dimensions of the component. This is a procedure well known in the powder metallurgy industry as repressing (also known as sizing or coining). An alternative approach is to use a fixture which locates and retains the bearing cap holes in position during sintering. Such a fixture could be made from either stainless steel or molybdenum and may consist of a U-shaped staple like structure, the legs of which are inserted into the bolt holes of the main bearing cap, thereby avoiding distortion during the sintering operation.
A common problem encountered in main bearing cap joints is “fretting”. This is the relative micromovement of the clamped contact surfaces of the bearing cap and bulkhead at high frequency that results in damage to the surfaces. Fretting fatigue is a possible outcome of this mechanism.
When a main bearing cap is constrained laterally in the block by a snap width channel as shown in FIG. 1, it can still move fore and aft (axially) and also from side to side (laterally) under load. Fore and aft motion is due to crankshaft bending (especially in V-engines) which causes a rocking motion. Since there is no restraint in this direction other than bolt clamp pressure, microsliding, and therefore fretting, can occur. Similarly, as illustrated in FIG. 24, when the crankshaft loading X is pushing the cap to the “right”, the left foot is pulled away from the snap channel as indicated by arrows Y to create a clearance at the area indicated by the arrow Z.
The present inventions which provides an integral hollow dowel on the bearing cap foot, improves this situation since the dowel serves to fix the position of the foot relative to the block. The fretting problem can be further mitigated by hollowing out the footprint of the bearing cap, which has the effect of raising the clamping pressure for a given bolt loading. By appropriate geometry, the remaining metal forms a land that increases the quality of clamping close to the bearing shell.
The technique of reducing area to raise clamping pressure is not new. However, it is very costly to achieve in volume production. The current predominant process of making bearing caps is by casting and machining. To machine precision hollow forms in a casting is prohibitively expensive. Using powder metallurgy, however, hollows can be molded into the foot with great precision for no extra cost beyond the initial tooling face form costs. Examples of four suitable forms for producing the indicated void areas V 1 -V 4 (approximately 0.010-0.020 inches deep) and corresponding planar contact areas A 1 -A 4 are shown in FIGS. 25 and 26. These voids may be used either with or without integral bosses as described above and maybe used in any combination. Experimentation with pressure sensitive paper and finite element analysis simulation shows that the hollowed out foot surface raises the clamping pressure by the following percentages (the void area given is for each void and there are two voids per foot as illustrated):
Clamping Load
Contact Area (in 2 )
Void Area (in 2 )
Increase
A1 = 1.0957
V1 = .2942
32%
A2 = 1.1373
V2 = .2936
33%
A3 = 1.0191
V3 = .2936
30%
A4 = 1.0504
V4 = .3159
33%
The previously described structures, materials and methods as applied to a bearing cap can also be applied to other powder metal components. Thus, the present invention avoids the problems of the prior art in locating two components of any suitable type fastened by a bolt 601 (FIG. 29 a-b ) by using a precision drilled counterbore 608 in one of the components 609 in combination with an integral dowel 612 made by powder metallurgy. The counterbore 608 may be provided around a hole 614 in the component 609 , which may be tapped, as shown in FIGS. 29 a and 29 b. The counterbore 608 is easily provided by commonly available computer numerically controlled (CNC) machining units. The integral dowel 612 formed on the mating component 616 engages the counterbore 608 and is self-centering on account of the tapered or conical shape of the integral dowel 612 fitting into and interfering with the counterbore 608 . The bolt 601 pulls the tapered lead angle of the conical outer surface of the integral dowel 612 into the counterbore 608 to give precise angular location. Plastic deformation of the dowel 612 and/or counterbore 608 may occur, and may be preferred in some applications, since such deformation contributes to precise relocation. Another advantage of this application is that it avoids the need for special conical-head bolts, and can use low cost regular headed bolts.
Another example of the application of this invention is a reciprocating engine connecting rod 620 and bearing cap 622 as shown in FIGS. 30 a and 30 b. In this case, the cap 622 has to be connected to the rod 620 prior to machining the bore 624 , 626 in which the crankshaft is journaled so that when the piston pin of the crankshaft (not shown) is inserted in the bore 624 , 626 after machining, it locates in the correct location. This ensures excellent roundness and quiet running of the engine piston. Current solutions include a method where the cap is fractured away from the rod, so that the fracture is used to precisely reassemble the rod and cap. This is fine for essentially brittle materials, but is inappropriate for the stronger, tougher materials used for highly stressed engines, since instead of cracking, they tend to bend and deform. In such cases, the current invention is an economical solution. The cap 622 is molded with two integral dowels 630 , 632 having outer conical surfaces that fit into and interfere with counterbores 634 , 636 formed around the drilled and threaded holes 638 in the rod 620 . Again, this invention separates locating and fixturing, which avoids the bolts bearing against the sides of the bolt holes, which can introduce distortion and stresses that can lead to engine failure.
Another application of the invention is to locate a powder metal component in a die cavity that will be filled with molten metal—especially aluminum. Often, it is necessary to reinforce an aluminum casting with a powder metal (P/M) steel insert. For example, such an application may include a main bearing insert in the lower half of an aluminum alloy combustion engine cylinder block or a bed plate. In such a case, the lower thermal expansion of the steel of the insert compared to the aluminum alloy of the crankcase is used to maintain bore-roundness when the engine temperature rises during running and the aluminum tries to grow away from the crankshaft, leaving a gap that can cause engine noise.
It is difficult to accurately position the insert within the die cast mold since the mold is open at insertion and closed during casting. The integral dowels solve this problem by both locating the bearing cap during mode closure and sealing off the bolt holes from molten aluminum.
FIG. 31 a shows the open die halves 650 , 652 and FIG. 31 b show it with a main bearing cap insert 654 impaled on two bullet-nosed pins 655 , 657 that hold it in position on the left half 650 of the die, while the opposite right side 652 of the die advances as the mold is closed (FIG. 31 c ). The right die wall has two shouldered bullet nosed pins 662 , 664 , one of which is shown in detail in FIGS. 32 a-d, that locate into the open ends of the holes 666 in the bearing cap insert 654 , when the mold is almost closed, as shown in FIGS. 32 a-d. The die mold halves 650 , 652 are finally clamped closed under a very high load, sufficient to crush the integral dowels and bring the mold halves together with sufficient force so as to prevent high pressure molten aluminum 674 from spurting out from the mold joint line. The shoulders 658 , 660 on the right hand set of pins 662 , 664 crush the integral cone-shaped dowels 670 to create a seal between the pins and the holes 666 . The seal prevents the molten aluminum 674 from entering the holes 666 . This action causes precise location of the cap 654 and eliminates the need for expensive drilling-out of aluminum flash that otherwise enters the bolt holes 666 where it solidifies. After solidification of the aluminum, the mold is opened as shown in FIG. 31 e, and the composite part is ejected.
The height of the integral dowel 670 (or crush ring) is chosen to accommodate normal variation in mold closing distance and to produce adequate resistance to provide a sealing pressure that prevents aluminum penetration. It is the intrinsic microporous nature of sintered powder metal that enables the material to behave in this way to effect a crush ring seal. The traditional gray cast iron that is often used for main bearing caps is very brittle and would crack and fragment under the crushing load. Ductile cast iron which is also used, would be more likely to deform without cracking, but the cost to machine the integral dowel shapes around the bolt holes would be prohibitive.
Experimental integral-dowel in-casting trials with a test mold in a high pressure die cast machine enabled the crush ring dimensions to be optimized. Subsequently these findings were confirmed in a casting trial that involved substituting P/M steel caps in a current production bed plate that contained five ductile cast iron bearing cap inserts. The tests showed that a dowel height of 0.04 inches (2 mm) with a 0.02 inches (0.5 mm) flat sealing face radial thickness and an angle of 45 degrees (90 degrees included cone angle) worked well in locating the in-cast insert. This also gave 100% sealing against aluminum ingress of all the bolt holes in a trial of 100 holes, compared to at least 70% of holes in the cast iron which suffered aluminum leakage without the integral dowels.
Preferred embodiments of the invention have been described in considerable detail. Many modifications and variations to the preferred embodiments described will be apparent to those skilled in the art. Therefore, the scope of the invention should not be limited to the preferred embodiments, but should be defined by the claims which follow.
|
A sintered powder metal (P/M) component has an integrally formed tapered boss surrounding its bolt hole which extends into counterbores in a component to which it is assembled and produces plastic conformance between the boss and the counterbore when the boss is seated in the counterbore. The P/M component can then be removed from the other component and reassembled to it, with the boss fitting perfectly back into the bore with the plastically deformed surfaces fitting back together precisely to determine the relative positioning of the two components. The boss is tapered, a moat may surround it, and the boss may be provided with axial splines and/or be oblong in the axial direction. Bosses such as these may be applied to two components in general, at least one of which is powder metal, such as a main bearing cap, a sensor ring for measuring the timing of an internal combustion engine and a connecting rod bearing cap. Such bosses may also be applied to a casting insert in which the boss is crushed when the die is closed so as to seal off the surrounded hole during casting.
| 5
|
BACKGROUND
[0001] Offshore installation of wind farms has been known for some time. Typically, the installation process for individual wind turbine systems involves a lengthy process in which individual components and/or parts are transported to the offshore site by various cargo ships, barges, and other vessels. Also typical is the need for one or often many crane-carrying ships to be deployed to lift the wind turbine components and parts into the installation position such that the components and parts can be installed. This piecemeal installation process can be cumbersome and take a great deal of time as many different specialized vessels and installation personnel are needed to perform each step of the process. As a result, the installation process can also incur significant financial expenses. Additionally, this has limited the ability to install smaller scale wind farms as the use of these specialized vessels often needs to be for installation in volume. Repair and replacement of individual wind turbines can also be extremely inefficient and costly as the same specialized vessels and specialized personnel need to be shipped to and from the offshore locations of the wind farms.
[0002] A typical offshore wind turbine installation project often starts with the installation of heavy concrete and/or metal foundations that may be installed on the sea floor in pre-planned locations. There are many different types of foundations, including specialized foundations that are configured for certain environmental conditions at a given site. These foundations can include heavy pre-fabricated concrete bases, monopile foundations that are inserted into the seabed, and tripod and other similar foundations that may also be inserted into the seabed. After installation of the foundation, towers are typically constructed, the components of the tower being shipped onsite by one vessel and the tower being lifted piece-by-piece into place and attached to the foundation by a crane ship or other specialized vessel having a crane. Next the turbine, which typically includes a drive shaft, transmission, and generator all housed in a nacelle housing, can be lifted into position and attached to the top of the tower. Following this, the turbine blades may be attached to the portion of the drive shaft that extends outwardly from the nacelle housing. Often, each of these components may arrive on different vessels and need to be attached by specialized crane ships or other specialized vessels.
[0003] Specially configured cable laying ships can also be deployed to lay electrical lines or install other specialized equipment needed to gather and transmit the power being generated by the turbines. Cable will also often be run to an onshore facility for use of the generated electricity onshore. Depending on the plan for a particular wind farm, the cable running between foundations may be installed before or after the construction of the rest of the wind turbines.
[0004] As has been described above, the specialized equipment and skilled personnel needed to install a wind farm can be extensive and costly. Thus, there exists a need for a more efficient offshore deployable wind turbine system and method.
SUMMARY
[0005] To solve the various problems associated with constructing wind turbines and/or wind farms offshore, a new apparatus, method, and system, for installing site-deployable wind turbines offshore has been developed and is described herein. The site-deployable wind turbine described herein can be substantially assembled onshore and includes a floating structure and a tower that is extendable at the installation site. A pivoting system can also be configured to couple the wind turbine and turbine blades to the extendable tower in an on-site and offshore-deployable configuration. The entire system can be substantially assembled onshore, removing many of the logistics issues and/or need for specialized equipment and vessels offshore. After the site-deployable wind turbine is delivered to an offshore location, the site-deployable wind turbine is placed into a resting position such that its floating structure is securely anchored to the sea floor. The extendable base and pivoting system can then be articulated such that the wind turbine and turbine blades are placed into their functional positions and the wind turbine can begin generating electricity.
DRAWINGS
[0006] Various aspects and attendant advantages of one or more exemplary embodiments and modifications thereto will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
[0007] FIG. 1 is a side perspective view of an exemplary embodiment of an offshore deployable wind turbine.
[0008] FIG. 2 is a top perspective view of an exemplary embodiment of an offshore deployable wind turbine.
[0009] FIG. 3 is a side perspective view of an exemplary embodiment of a wind turbine and wind turbine blades.
[0010] FIG. 4 is a top perspective view of an exemplary embodiment of a wind turbine and wind turbine blades.
[0011] FIG. 5 is a side perspective view of an exemplary embodiment of an offshore deployable wind turbine after installation.
[0012] FIG. 6 is a side perspective view of an exemplary embodiment of an offshore deployable wind turbine resting on the sea bed and prior to extension of the turbine tower.
[0013] FIG. 7 is an angled side perspective view of an exemplary embodiment of an offshore deployable wind turbine.
[0014] FIG. 8 is an angled side perspective view of an exemplary embodiment of an offshore deployable wind turbine during extension of the turbine tower.
[0015] FIG. 9 is an angled side perspective view of an exemplary embodiment of an offshore deployable wind turbine during extension of the turbine tower.
[0016] FIG. 10 is a side perspective view of an embodiment of an offshore deployable wind turbine in a buoyant configuration being transported to an installation site by a ship.
[0017] FIG. 11 is a side perspective view of an embodiment of offshore deployable wind turbines being transported in an alternative configuration to an installation site on a ship.
[0018] FIG. 12 is a top perspective view of an embodiment of offshore deployable wind turbines being transported to an installation site on a ship, as also shown in FIG. 11 .
[0019] FIG. 13 is a side perspective view of an alternative embodiment of an offshore deployable wind turbine configured having a gravity base configured with divided cellular structures and a skirt added to provide stability to the structure if the soil characteristics require.
[0020] FIG. 14 is a side perspective view of an embodiment of an offshore deployable wind turbine showing each step of deployment once at the installation site.
[0021] FIG. 15 is a side perspective view of an alternative embodiment of an offshore deployable wind turbine configured having a gravity base with divided cellular structures and labeled with one possible configuration of materials that may be placed in the cellular structures.
[0022] FIG. 16 is a side perspective view of an alternative embodiment of an offshore deployable wind turbine configured having a floating structure with divided cellular structures and labeled with one possible configuration of materials that may be placed in the cellular structures and one possible anchoring configuration.
[0023] FIG. 17 is a top perspective view of an alternative embodiment of an offshore deployable wind turbine configured having a floating structure and shown with one possible anchoring configuration, which can be modified according to environmental condition, such as wind, currents and wave patterns that may be present at a specific installation location.
[0024] FIG. 18 is a side perspective view of an alternative embodiment of an offshore deployable wind turbine configured with helical strakes.
DETAILED DESCRIPTION
[0025] Exemplary embodiments are illustrated in referenced Figures of the drawings. It is intended that the embodiments and Figures disclosed herein are to be considered illustrative rather than restrictive. No limitation on the scope of the technology and of the claims that follow is to be imputed to the examples shown in the drawings and discussed herein. Further, it should be understood that any feature of one embodiment disclosed herein can be combined with one or more features of any other embodiment that is disclosed, unless otherwise indicated.
[0026] As illustrated in FIG. 1 and FIG. 2 and as described in detail below, an embodiment of an offshore deployable wind turbine system 10 can be configured with a self-installable gravity base 20 to install the wind turbine on the sea bed or in other wetland areas on or offshore having adequate water depth, e.g. from 10 m to 40 m depth, though systems of varying dimensions may also be constructed to accommodate shallower or deeper waters. In an embodiment, the gravity base 20 can be constructed onshore and can be configured with an extendable tower 30 . While the extendable tower 30 is retracted and still onshore, the wind turbine 40 and its blades 42 can be mounted on top of the extendable tower 30 utilizing harbor or industrial infrastructure such as cranes. In an embodiment, the wind turbine 40 can be configured to include a drive shaft, transmission, generator, and other associated components. Optionally, a brake assembly and/or yaw adjustment components can also be included. Typically, each of these components will be configured in a nacelle housing, with a portion of the drive shaft extending outside of the housing such that the wind turbine blades 42 can be connected to the wind turbine 40 . In an embodiment, the uppermost part of the extendable tower 30 can be configured with a pivoting system 50 (pivoting system 50 is shown and described in greater detail in relation to FIG. 7 ) which allows the wind turbine 40 to initially be installed on its vertical axis, such that any configured wind turbine blades would be approximately parallel with the ground. This allows for the wind turbine blades 42 to be installed while the offshore deployable wind turbine system 10 is still onshore. When the relative height from the top of the extendable tower 30 to the ground allows, the pivoting system 50 can then be utilized so that wind turbine 40 can be positioned with its wind turbine blades 42 in the horizontal or working position.
[0027] In an embodiment, the gravity base 20 can be configured to have its own buoyancy during transport and then be employed as a gravity base, keeping the entire wind turbine in position once deployed. In such a configuration the buoyancy of the gravity base 20 may be produced by a network of cellular structures 22 (cylinders as depicted in FIGS. 1 through 9 ) that are structurally connected forming the hull of the gravity base 20 . The shape of the cellular structures 22 , as well as the diameter and length of the structures may vary according the desired configuration for a given installation site. The lower part of the hull may also be configured with a skirt (as shown in the embodiment illustrated by FIG. 13 ) in order to penetrate the seabed at the installation site, thus providing additional stability. The upper portion of the gravity base 20 can also be configured with a deck (not shown) to allow personnel access to the extendable tower system 30 or alternatively a structure similar to the skirt shown in FIG. 13 could also be configured as a deck for personnel.
[0028] An embodiment of this system allows for the wind turbine and the wind turbine blades to be assembled on ground with the rotating axis in a vertical position as shown in FIG. 3 . This allows for the assembly operation to be performed onshore rather than offshore, as is the case with traditional systems. Once the blades are attached to the turbine, the system may be lifted to and installed on top of the extendable tower 30 . Further, in an embodiment, a pivoting system 50 can be configured at the top of the extendable tower 30 , and in this configuration the wind turbine 40 will be attached to the pivoting system 50 or both the pivoting system 50 and the extendable tower 30 , depending on the particular configuration.
[0029] In an embodiment, the connection between the extendable tower 30 and the wind turbine 40 may include a pivoting or articulation system 50 that allows the turbine 40 to rotate from the normal working position, as illustrated in FIG. 5 , to the position with the axis on the vertical, as illustrated in FIG. 6 , thus allowing a 90 degree inclination around the pivoting axle. This pivoting system 50 may be activated using conventional hydraulic or mechanical systems such as hydraulic cylinders or gears activated by electric motors.
[0030] In an embodiment, the pivoting system 50 may be used during transport and/or installation of the wind turbine system 10 when the height of wind turbine system 10 is not sufficient to prevent the blades 42 from touching the water or ground. The pivoting system 50 can also be used for maintenance, such as to repair the wind turbine system components, wind turbine blades 42 , or for decommissioning of the wind turbine system 10 .
[0031] In an embodiment, and as illustrated in FIGS. 1-9 , the extendable tower 30 can be made of a number of concentric cylinders 32 that might be extended (or activated) by various methods. In an embodiment, extendable tower 30 may include two or three concentric cylinders 32 , but it may also include more, depending on the desired configuration. In an embodiment, to facilitate the extension of the cylinders, water may be injected in the annulus of the cylinders, which may be dry and empty during transport. In an alternative configuration, the cylinder may be extended (or activated) by emptying the cylinder annulus which is initially flooded. In any activating method, the concentric cylinders are extended vertically and may further be connected structurally (e.g. by welding, or connecting and securing sections mechanically using bolts or other methods) in order to create a rigid tower to support the wind turbine system.
[0032] In an embodiment of the extendable tower system 30 , concentric cylinders are utilized in the same way as conventional hydraulic systems, that is, a liquid may be pumped with high pressure to the interior of the cylinder causing an axial force which pushes an internal piston. The piston pushed by the internal pressure in the external cylinder (liner) is the section of the tower that will be extended. After completing the extension, welding or other types of structural connections may be made at the connection between each internal cylinder) and each external cylinder). This procedure may be repeated to the subsequent sections of the tower until the tower reaches its operating height.
[0033] Optionally, and similar to the configurations described in the previous paragraphs, it is possible to configure the wind turbine and the blades on a pivoting base in a way that facilitates the transport to an installation site with the wind turbine system configured in this manner.
[0034] In an embodiment, at the installation location, with the help of a compressor, air is injected into the internal cylinder that forms the telescopic tower. The air will displace the water and reduce the cylinder weight, thus extending the tower 30 and raising the wind turbine 40 and wind turbine blades 42 . In case the wind turbine 40 is transported with its rotor axis in the vertical position, the wind turbine 40 and wind turbine blades 42 can be rotated using the pivoting system 50 to put the wind turbine 40 into the operating position.
[0035] In an embodiment, if the cylinder does not have enough buoyancy to raise the rotor to the desired height, a second installation support device can be employed to provide the necessary elevation. Such a device may be composed of two identical concentric cylinders with a closed annulus at the top section. In this configuration, the cylinders will be initially flooded and will have compressed air injected in the annulus to promote buoyancy and consequently elevation. This device will be assembled around the pool of cylinders and will form the extendable tower.
[0036] Once the internal cylinder reaches the desired height, it may be integrated with the external cylinder in a manner creating a waterproof connection. The installation support device is then retracted to its original position by relieving the pressure of the compressed air in the annulus. The device may also be fixed to the external cylinder. Compressed air is then injected into the device and into the tower cylinder. The turbine is then moved to a higher position.
[0037] The process above is repeated as many times as necessary so that the extendable tower has its sections completely elevated and the wind turbine reaches its operating position.
[0038] FIG. 10 illustrates one possible transportation method for an offshore deployable wind turbine system 10 . In this embodiment the deployable wind turbine system 10 is configured to be buoyant and float while being towed behind a ship 60 or other vessel. A high tensile strength cable 62 or rope can be configured between the turbine system 10 and ship 60 , such that the turbine system 10 is towed behind the ship 60 . One or multiple turbine systems 10 may be towed behind a ship 60 at a given time.
[0039] FIG. 11 and FIG. 12 illustrate an alternative transportation possibility where multiple deployable wind turbine systems 10 can be transported to the installation site on a transportation ship 70 or other suitable vessel. In this embodiment, the transportation ship 70 may also be configured with one or more optional cranes 72 to assist in loading and unloading the deployable wind turbine systems 10 at the dock and installation site.
[0040] FIG. 13 illustrates an alternative embodiment of an offshore deployable wind turbine system 110 , shown configured with a self-installable gravity base 120 comprising cellular structures 122 , an extendable tower 130 comprising concentric cylinders 132 , wind turbine 140 , and wind turbine blades 142 . This embodiment can also optionally be configured with a pivoting system 150 . This alternative embodiment includes additional features regarding the gravity base 120 . In this embodiment, cellular structures 122 can each include a plurality of inner cavities 134 which can be filled with various materials depending on the configuration desired for installation and/or the installation site (see FIG. 15 and description regarding FIG. 15 below for additional details regarding possible filler materials for the inner cavities). An optional skirt 160 can also be configured on this or other embodiments of the wind turbine systems described herein. In addition, optional lower base 150 can be included, which may comprise hollow cylinders 152 which are open on the bottom and therefore can be embedded into the sea floor. Optional skirt 160 can then serve to stabilize the lower base 150 on the sea floor.
[0041] Further, in an embodiment, the height of an offshore deployable wind turbine system can be highly configurable. The cellular structures that form the gravity base of a given embodiment can be varied in height and customized for a given installation site. Further, height can be added or removed from a particular gravity base by lengthening or reducing the length of the cellular structures of a deployable wind turbine system. These cellular structures can be welded or cut to provide custom installation heights to meet the needs of a particular installation location.
[0042] In another alternative embodiment (not shown), an offshore deployable wind turbine can be installed in the buoyant state and connected to the sea floor with cables or anchors.
[0043] FIG. 14 is a side perspective view of an embodiment of an offshore deployable wind turbine showing exemplary steps of deployment once at the installation site. Offshore deployable wind turbine 10 a shows an example of initial deployment on the sea floor. Offshore deployable wind turbine 10 b shows an example of initial deployment on the sea floor where the extendable tower has started to raise the turbine. Offshore deployable wind turbine 10 c shows an example of initial deployment on the sea floor where multiple concentric cylinders of the extendable tower are deployed. Offshore deployable wind turbine 10 d shows an example of initial deployment on the sea floor where the extendable tower is fully raised. Offshore deployable wind turbine 10 e shows an example of initial deployment on the sea floor where the extendable tower is fully raised and the turbine has been pivoted into a functional position.
[0044] FIG. 15 illustrates an alternative embodiment of an offshore deployable wind turbine system 210 , shown configured with a self-installable gravity base 220 configured with cellular structures 222 , which can each include a plurality of inner cavities 234 which can be filled with various materials depending on the configuration desired for installation and/or the installation site. Within one particular cellular structure 222 , inner cavities 234 may be separated from each other by placing a steel plate or other physical barrier across the inner diameter of cellular structure 222 at the desired location. It should be noted that the number of inner cavities 234 may differ from what is illustrated in FIG. 15 . Further, the gravity base can also be configured as a plurality of rectangular containers, one large rectangular container having a hollow center section, one large cylinder having a hollow center section, or other configurations. Each of these possible configurations can further be subdivided to have multiple inner cavities similar to the embodiment illustrated in FIG. 15 . The materials that can be placed in the individual cavities may include various materials. For example. the lowermost of the inner cavities 234 may contain hematite or concrete to help anchor a deployable wind turbine system 210 . The next inner cavities up from the sea floor may be filled with water, and the uppermost inner cavities may be filled with air for buoyancy or simply be a void space that does not need to be filled. Each of these sections can either be filled during construction, at the dock, during transport, or at the installation site and the filler material can be customized for a particular installation site. The lower base 250 can be configured as hollow with an open bottom to be inserted into the sea floor or it can optionally be sealed and filled with concrete or other material depending on the particular installation site.
[0045] FIGS. 16 and 17 illustrate alternative embodiments of an offshore deployable wind turbine 310 configured having a floating structure 320 with divided cellular structures 322 and labeled with one possible configuration of materials that may be placed in the cellular structures 322 and one possible anchoring configuration that includes cables 370 and anchors 380 to the sea floor. This embodiment may further include an extendable tower 330 comprising concentric cylinders 332 , a wind turbine 340 , and wind turbine blades 342 . This embodiment can also optionally be configured with a pivoting system 350 . In this embodiment, the divided cellular structures 322 can each include a plurality of inner cavities 334 a , 334 b , and 334 c , which can be filled with various materials depending on the configuration desired for installation and/or the installation site. Here uppermost inner cavity 334 a is shown as a void space that may contain air to make the deployable wind turbine 310 buoyant. The uppermost inner cavity 334 a can also be referred to as void tanks (“VOID”) which can further be configured to be closed and sealed in a manner that they will provide sufficient buoyancy to the structure during installation and such that they will continue to provide buoyancy during the operational life of the structure. Middle inner cavity 334 b , the first section below the void tanks, can also be referred to as variable ballast tanks (“VB”) and may be filled with water such that buoyancy can be added or subtracted from the structure by increasing or decreasing the amount of water inside the variable ballast tanks or middle inner cavity 334 b . The first section below the variable ballast tanks 334 b are the lowermost inner cavity or fixed ballast tanks (“FB”) 334 c . The fixed ballast tanks 334 c may be filled with hematite or concrete as to provide additional mass at the lower portion of the structure and increase its intrinsic stability. Other materials similar to hematite or concrete may also be used to fill the fixed ballast tanks 334 c . Additionally, an optional heave plate 360 can be configured, similar to the skirt 160 configured with respect to FIG. 13 , but in this configuration, the heave plate can provide a damping effect over vertical movements of the floating gravity base 320 .
[0046] Referring to FIG. 17 , cables 370 and anchors 380 can be configured in a cross pattern as shown, or in an alternative embodiment more or less cables and anchors may be used to keep the offshore deployable wind turbine 310 in position.
[0047] FIG. 18 illustrates another alternative embodiment of an offshore deployable wind turbine 410 which can be configured to either be a floating or non-floating (fixed on the sea bed floor) embodiment, as described in more detail above. Either embodiment may further include helical strakes 490 . Helical strakes 490 may be formed of any suitable material, including but not limited to steel, plastic, or polyurethane. Helical strakes 490 may be welded or clamped to the cells of the gravity base or floating structure and can follow a spiral path around the cells. The strakes will typically be added during manufacturing or assembly onshore. In general, the helical strakes 490 can help prevent vortex induced vibration which may occur when the offshore deployable wind turbine is moved through the water causing laminar flow to transition to turbulent flow, or during operation when currents pass through the offshore deployable wind turbine. In the case of the gravity base 460 , the cylindrical structures can cause the outer part of the fluid flowing by to have a higher speed that the internal fluid, which in turn can generate a difference in pressure and cause an alternating vortex and turbulence.
[0048] In a helical strake embodiment of the offshore deployable wind turbine, the pitch of the helix can be adjusted depending on the project to maximize the reduction in vortex induced vibration. The diameter of the cellular structures that make up the gravity base or floating structure can also be configured to reduce vortex induced vibration.
|
A method and system for installing a site-deployable wind turbine offshore. The wind turbine can be substantially assembled onshore and includes a floating structure and a tower that is extendable at the installation site. A pivoting system can be configured to couple the wind turbine and turbine blades to the extendable tower in an onsite deployable configuration. After the wind turbine is delivered to an offshore location, the wind turbine is deployed and the extendable base and pivoting system can be made to deploy the wind turbine and turbine blades into functional positions such that the wind turbine can begin generating electricity.
| 5
|
BACKGROUND OF THE INVENTION
This invention relates, generally, to appliances and, more particularly, to appliances such as electric hair dryers, curling irons, kitchen appliances and the like which include a means for disconnecting the electrical current therein should the device become saturated with water to the point or for any other reason where a shock hazard exits.
The state of consumer appliances in present day households indicate that usage of electrical devices is increasing. There are many types of devices, particularly handheld types, which generally fall into three categories--health and beauty, kitchen and electric hand tools. Health and beauty handheld electrical devices are generally comprised of electric hair dryers, curling irons, electric razors; kitchen devices are generally mixers, blenders, coffee makers, etc.; while handheld electric tools are generally comprised of drills, hedge-clippers, handheld saws and the like.
The reason for the proliferation of these devices is quite simple. They are generally inexpensive to purchase, while being convenient and well adapted to their individual purpose. However, use of these devices produces a distinct danger, particularly when used around water, or even steel wool pads. This danger is in the form of electrocution. Frequency of electrocution as a result of these types of devices, particularly handheld electric hair dryers, is increasing. Since these types of devices are typically used in wet areas, such as by sinks, tubs or outside, it is readily apparent that there is a significant likelihood that the object will either be dropped into water, such as a bathtub or a sink, or that it may become contaminated with water, such as by splashes when clipping shrubbery by moisture which is present on grass, adjacent foundations or the like.
Presently, ground faulting interruptors are being used in new and renovation construction, which are expressly for the purpose of minimizing the chances of electrocution. However, these types of devices have not been integrated into existing housing, which comprises the bulk of usage areas. Hence, safety is a problem from place to place and not merely between devices.
Another significant and distinct disadvantage problem, whether or not conventional ground faulting directors are being utilized, is that fault current must generally flow through the user before the device detects and interrupts the flow of current therethrough. Another disadvantage is in the situation where there are no conventional ground fault interrupters and a separate interrupter is utilized with the device. Generally, conventional ground fault interrupters are somewhat bulky and cumbersome due to the fact that they not only detect and interrupt the flow of ground fault current, but also have user accessible test and reset buttons. This therefore drives up the cost and size requirements of any device wishing to utilize current interruptors.
Accordingly, it is an object of the present invention to provide a current path in a handheld electrical device which allows a current interruption device to operate more quickly.
It is a further object of the present invention to provide a current path in an electrically powered handheld device which avoids leakage current paths through the user of the device.
It is yet another object of the present invention to produce a device which incorporates a current interruption mechanism as an integral part thereof.
Yet another object of the present invention is to produce a handheld electrical device having current interruption integral therein wherein reset, once the device has been tripped, can only be accomplished by a special tool.
A still further object of the present invention is to produce a handheld electrical device having a current interrupting mechanism integral therein which is resettable only after inspection by a trained service person.
Yet another object of the present invention is to produce a handheld electrical device having an interrupting safety mechanism which is inexpensive to manufacture.
Another object of the present invention is to produce a device which adds few additional components and is easy to assemble.
Still a further object of the present invention is to produce a current interruption mechanism which is small and compact and may also fit into existing housing configurations and sizes.
Yet another object of the present invention is to produce a safety device which is retrofittable to existing designs. Such a device is taught by the present invention.
It is another object of the present invention to produce a safety device which will function even when the handheld device is not plugged in.
Finally, another object of the present invention is to produce a device having an electrical path for driving a load therein which comprises a ground plane disposed within the device in order to provide an electrical path, a detector with an input for detecting the presence of electrical current in the ground plane and an output for producing an electrical signal after detection of the presence of electrical current in the ground plane, and a current interruptor which has an input adapted to receive the output of the detector and an output for interrupting the electrical path in the device.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference may now be had to the accompanying drawings in which:
FIG. 1 is a representational view of an electric handheld hair dryer incorporating the present invention;
FIG. 2 is a view substantially identical to FIG. 1 illustrating alternate current interruption mechanisms; and
FIGS. 3 and 4 show two alternate circuit configurations for effecting current interruption.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a diagrammatic view of the device encompassing the preferred embodiment of the present invention. Shown is an electric handheld hair dryer 10. It is to be understood that other types of handheld electric devices can and may be used without departing from the spirit and scope of the present invention such as, for example, electric curling irons, hand tools and the like. The hair dryer is comprised of a barrel 12 and handle 14 housing a number of components therein. At one end of handle 14 is an electric cord 16 which terminates at plug 18 and is suitable for typical household use. An ON/OFF lever 20 is disposed at the base of handle 14 and may be of any suitable type such as slide, rotary or the like and may be single pole, double pole or any other suitable or desired configuration. At one end of barrel 12 is a front grill 22 which permits the passage of heated air therethrough as described more fully below. A screen 24 is typically located at the rear end of barrel 12 and utilized so that foreign matter, i.e. hair, cannot be sucked into barrel 12. A blower or fan is generally disposed adjacent screen 24 and takes air in through screen 24 and passes air over heating element 28. Heating element 28, in turn, heats the air before the air exits through the front grill 22. A ground screen or plane 30 is used to electrically connect front grill 22 to screen 24. Further, ground screen/plane 30 provides a continuous electrical path throughout the interior of hair dryer 10. By ground screen/plane 30 is meant any electrically conductive means to direct the current to a current interruptor device and, therefore, the ground plane 30 is not necessarily at earth "ground" potential. In this manner, should hair dryer 10 fall into water or should hair dryer 10 become wet to an unacceptable level, a ground path is provided between electrically conductive "live" areas in the hair dryer and the ground screen. The electrical connection between grill and screen 22 and 24 respectively via a ground screen/plane 30 may be accomplished in any number of suitable ways, such as crimp type fits, compression type fits, soldering or welding to mention a few. Any of the live areas can and may include exposed portions of hot or neutral wires 50,52 respectively, portions of heating element 28 or blower motor 26 as well as portions of ON/OFF switch 32 having load contacts 34 therein.
It has been determined that the ground screen/plane 30 may be in a number of embodiments or configurations, although all are acceptable as long as a continuous electrically conductive ground path is provided. Accordingly, the ground screen/plane 30 may be in the form of a metal screen, or plating disposed on the interior portions of hair dryer 10, or on one side of heating insulators (not shown) which are typically disposed in barrel 12, may be fabricated from aluminum or other type of metal foil. In this manner, a current return path is readily available between any of the electrically "live" components inside hair dryer 10 (as previously discussed) through water and hence to ground screen/plane 30. It has been found that this provision of an alternate return or ground path minimizes or eliminates the chance of current flow through a user, particularly when the unit merely has too much water present such as having water splashed on to it as it lies adjacent a sink or, in the case of a hand tool, it is laid down into or adjacent a puddle.
It has been found that the provision of a ground screen/plane 30 provides another distinct and significant advantage in that present hair dryer or appliance design need not be changed from two conductor to three conductor cord sets (not shown) since present designs are most cost sensitive. For this reason I have found that provision of an interrupt device 35, which is contained directly in handle 14, is appropriate. The interrupt device 35 is generally comprised of two portions, an electronic components portion 37 and a mechanical interlock portion 39. The function of the electronic component portion 37 is to detect and utilize electrical energy passing through or present on ground screen/plane 30. The mechanical interlock 39 is used to physically disconnect incoming power via electric cord 16 to the remainder of hair dryer 10.
The electronic components 37 include field effect transistor (FET) 48 having its gate terminal (G) connected to a terminal of biasing battery B a , with the remaining lead of the battery B a connected to ground screen/plane 30. Therefore, the biasing battery B a will render the FET 48 to become conductive in the event of any current leakage between ground screen/plane 30 and elsewhere in the device 10. A lithium or hearing-aid type battery B a (or other long shelf life battery) may be utilized to provide an internal POWER SUPPLY which would cause mechanical interlock 39 to be energized regardless of whether plug 18 has power applied thereto, should the hair dryer be immersed or present a shock hazard or the like. Therefore, when plug 18 is energized, the device would have been previously tripped and no chance of electrical short or the like can be applied to the user.
Source terminal (S) of FET 48 is connected to hot lead 50 and to one terminal of condensor Cl. The remaining terminal of condensor Cl is connected to one terminal of coil 40 and to the cathode of diode Dl. The remaining terminal of diode Dl is connected to neutral lead 52. The drain terminal (D) of FET 48 is connected directly to the remaining terminal of coil 40.
Coil 40 is preferably a "latch" type solenoid coil having a movable rod 42 disposed therein. In the preferred embodiment of the present invention, movable rod 42 is either an integral part of or connected to ball 36. Therefore, energization of coil 40 causes ball 36 to be urged downward. However, it is to be understood that rather than rod 42 pulling ball 36 downward, similar satisfactory results may be obtained by having rod 42 merely push ball 36 upward. A stop 38 is provided to maintain ball 36 in a stationary position with ball 36 being used to bias spring-type load contacts 34 against appropriate terminals of ON/OFF switch 32. In this manner, when rod 42 is urged downward, due to electromotive force present in coil 40, ball 36 is similarly urged downwards with the result that load contacts 34 will electrically and mechanically disconnect from the contacts of ON/OFF switch 32.
Therefore, when current exists between ground screen 30 and hot wire 50 (or neutral wire 52), current will be permitted to flow through FET 48 with the result that coil 40 will become energized. Accordingly, in the preferred embodiment of the present invention, a ground fault in the traditional sense is not required in order to "trip" the present invention and prevent user injury. Rather, a current between ground screen/ plane 30 and any electrically live component, such as is present a shock hazard, will be detected and will result in operation of interrupt device 35. This shock hazard may be the result of immersion, high humidity, steel wood used during cleaning, or as a result of damage. Such damage may occur when, for example, a user tries to clean a toaster by using a knife and causes a short-therein.
In this manner, the "user" is not required to be the return path in a circuit and hence subject to shock before the device will trip. Another significant advantage of a battery in this type of circuit operation is that even if plug 18 is not energized, that is in a receptacle, the battery supplies the power to enable the interrupt device 35 to function. Accordingly, FET 48 and hence coil 42 are in effect "biased" in order to ensure rapid response time. Consequently, when the hair dryer 12 is eventually plugged in, there will be no chance of a shock hazard.
When tripped, rod 42 will, as previously mentioned, preferably be urged downward. Further, in the preferred embodiment of the present invention, rod 42 is of an appropriate length such that after tripping it cannot and will not emerge through reset aperture/keyway 44 present in the underside of handle 14. In the preferred embodiment of the present invention, return of rod 42 to the normal position which enables load contacts 34 to be energized, cannot be accomplished except by use of reset key 46. Accordingly reset key 46 must be passed through reset aperture/keyway 44 in order to properly reorient rod 42. Preferably, keyway 44 and hence reset key 46 are of a cross-type configuration. In this manner, reset may only be accomplished by an individual having the correct reset key. Accordingly, it is preferred that only qualified service individuals be given a reset key, thereby adding an extra level of safety. Should interrupt device 35 trip, the user would be required to bring the device to any service center having qualified technicians who will then examine hair dryer 10 to ensure that the interior is dry, there are no damaged components, frayed wires or extraneous matter or the like, before resetting interrupt device 35.
Additionally, in the preferred embodiment of the present invention, it is preferred that load contacts 34 and ON/OFF switch 32 be at least moisture proof and preferably waterproof. Therefore, should a hair dryer be immersed in water, water cannot flow into the switch 32 which might permit a flow of current through switch 32 to load contacts 34 at any time. Alternately, in the present invention, a reset aperture/keyway may not be utilized with the result that a trained service technician must open up the hair dryer to ensure that they physically inspect the interior thereof and to effectuate reset of mechanical interlock 39.
Further, in the preferred embodiment of the present invention, condenser Cl is an electret which is well known and understood by one skilled in the art. An electret is highly desirable since it retains a charge, absent outside electrical stimulation. In this regard, it is not necessary for condenser Cl to build a charge prior to energization of coil 40. Since the electret retains its own charge, quick energization of coil 40 is inherent. Hence this cuts down significantly on the interrupt time of mechanical interlock 39. This is especially important since electromagnets, such as coil 40, typically have a relatively "long" energization time when viewed in terms of the time required for electrical hazard to an individual. For this reason, a fast acting FET is preferred. Additionally, should it be desired, a transient filter (not shown) may be inserted in series circuit relationship between the source terminal of FET 48 and the electrical connection to the ground screen/plane 30 should nuisance trips be a concern or a problem.
Referring now to FIG. 2, a view substantially similar to FIG. 1 is shown. Accordingly, only the differences between FIGS. 1 and 2 will be explained herein. Shown is trigger mechanism 54 which has a number of electrical appliances connected thereto. Ground screen/plane 30 is connected via terminal A to trigger mechanism 54 while similarly terminals D and E of trigger mechanism 54 are respectively connected to coil 40. Terminal B is connected to the hot lead 50 while terminal C is connected to neutral lead 52, although, for the reasons previously mentioned, terminals B and C may be reversed. Accordingly, trigger mechanism 54 may encompass a variety of different components or alternate embodiments.
Accordingly, referring now to FIGS. 3 and 4, schematic representations of alternate embodiments of the present invention may be utilized. More particularly, trigger mechanism 54, as shown in FIG. 3, would supplant electronic components 37 disposed in FIG. 1 while similarly trigger mechanism 54 of FIG. 4 would supplant electronic components 37 of FIG. 1. Referring to FIG. 3, terminal A and hence ground screen/plane 30 is connected to one terminal of condenser C2. The remaining terminal of condenser C2 is connected to the gate terminal of FET 56. The drain terminal of FET 56 is connected to terminal D or one terminal of coil 40. Hot lead 50, terminal B, is connected to the source terminal of FET 56 and to one terminal of condenser C3. The remaining terminal of condenser C3 is connected to remaining lead, terminal E for coil 42 and to the cathode of diode D2. The anode of diode D2 is connected to terminal C, neutral lead 52. It is preferred that condensers C2 and C3 be electrets, thereby providing a certain amount of bias to FET 56 and coil 42 for the purpose of decreasing the "trip time" of mechanical interlock 39. Additionally, by connecting to neutral lead 52, one half-cycle of delay time is eliminated since alternating current is utilized and hence lead 52 is at a high potential when lead 50 is at a low potential.
FIG. 4 performs in a manner similar to that of FIG. 3 but is, of course, somewhat simpler. There, terminal A is connected to one terminal of condenser C4 while the remaining terminal of condenser C4 is connected to the gate terminal of FET 58. The drain terminal of FET 58 is connected to the D terminal while the source terminal of FET 58 is connected to terminal B and to one terminal of condenser C5. The remaining terminal of condenser C5 is connected to terminal E. As before, it is preferred that condensers C4 and C5 be electrets, thereby shortening the interrupt time.
It is to be understood that although only three variations of electronic components are shown, other variations may be utilized without departing from the spirit and scope of the present invention. For example, a standard ground fault interrupter circuit such as LM1851 Ground Fault Interrupter produced by National Semiconductor Corporation which are readily available and known to one skilled in the art may be utilized. Additionally, other types of mechanical interlocks may be utilized without departing from the spirit and scope of the present invention. Further, current interruption may be accomplished by replacing the electronic components and/or mechanical interrupt with other suitable current interrupting devices such as, for example, high current transistors latching relays, opto-isolators, and the like.
Accordingly, the present invention produces an extremely safe device for individuals to utilize which uses present design without the need for retooling and the like. Additionally, the present invention adds minimal cost while substantially increasing the safety of handheld devices such as hair dryers and the like. Further, the present invention may be encompassed into other small appliances such as mixers, blenders and other kitchen-type aids.
Having thus described the present invention in detail, it is to be understood that the foregoing description is not intended to limit the spirit and scope thereof. What is desired to be protected by Letters Patent is set forth in the appended claims.
|
A safety device for minimizing electrical shock to a user is taught. Briefly stated, a ground plane is disposed inside an electrical tool or device. Should the device become immersed in water or become unreasonably wet, the plane provides a path of electrical current, which energizes an interrupt device contained therein. The interrupt device disconnects power from the device. Further, reset can only be accomplish by a special purpose tool being urged through an aperture in the device case.
| 7
|
FIELD
The invention relates to spinal fixation systems and devices. More particularly, the invention relates to an improved fixation device having bone anchors and interconnecting components.
BACKGROUND
Traditional spinal stabilization systems include the type which has multiple bone anchors for attaching to the respective vertebrae, and a linking member secured to the bone anchors to prevent or limit the motion between the vertebrae. Anchors typically include pedicle screws and/or hooks. Linking members typically include rods and/or plates. Alternatively, the linking member may be a substantially flexible cord, which permits relative motion between the stabilized vertebrae, and a resilient spacer between each pair of linked bone anchors. One exemplary system is made of braided Polyethylene Terephthalate (PET; available under the Sulene™ brand from Sulzer Orthopedics, Ltd., Baar, Switzerland). An exemplary spacer is made of Polycarbonate Urethane (PCU, also available under the Sulene™ brand name from Sulzer Orthopedics, Ltd.).
In the prior exemplary systems, the spacer generally operates to resist, without completely preventing, motion of the bone anchors toward each other, while the cord operates to resist motion of the bone anchors away from each other. Because the spacer and cord are generally more flexible than rigid metal rods or plates, systems employing a cord and/or spacer arrangement generally permit movement between vertebrae and thus provide a more dynamic stabilization system than those employing rigid linking members. Additionally, the interconnections between the anchors, spacers, and cords may permit relative motions that are meant to be prevented with rigid metal systems, which also provide a more dynamic stabilization system than those employing rigid linking members.
Each of the foregoing types of systems may have advantages and disadvantages in a given patient condition. Because of the diverse patient conditions requiring treatment, however, there is a need in the art for a spinal stabilization system that combines the advantages of rigid and dynamic stabilization systems, and permits the physician to modify the rigidity of the system based on the needs of the patient.
SUMMARY
The invention disclosed herein is aimed at providing a method and apparatus for providing improved spinal treatment to individual patients. According to one embodiment, the present invention is an implantable orthopedic stabilization device comprising a cord, at least one pair of bone anchors, wherein each bone anchor includes a bone attachment portion adapted to engage a vertebra, and a head portion attached to the bone attachment portion and including a cord receiving portion and a clamping mechanism adapted to secure the cord to the bone anchor, and a substantially incompressible spacer having a channel sized to receive the cord therethrough. The spacer is adapted to be positioned between and maintain a predetermined spacing between the head portions of the at least one pair of bone anchors. The spacer further includes an end surface configured such that the end surface can articulate along a face of at least one of the head portions of the at least one pair of bone anchors.
In another embodiment, the present invention is a method of stabilizing a portion of a spinal column of a patient comprising implanting first and second bone anchors into respective vertebrae with a substantially incompressible spacer positioned between head portions of the bone anchors, wherein each head portion has a cord receiving portion, and wherein the spacer comprises a channel adapted to receive a cord therethrough. Next, the method includes passing a cord through the cord receiving portions and the channel, and then securing the cord to at least one of the bone anchors. Next, the method includes applying a tensile load to the cord such that the head portions exert a compressive force on the spacer with a face of each of the head portions bearing upon one of a first and second end surface of the spacer. The step of applying the tensile load further includes setting the tensile load such that the compressive force permits a desired amount of articulation of the faces of the head portions along the respective end surfaces of the spacer.
While the invention is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:
FIG. 1 is a lateral elevation view of a human spinal column;
FIG. 2 schematically illustrates a posterior elevation view of the human spinal column with two spinal stabilization devices, according to one embodiment of the present invention, implanted therein;
FIG. 3 is a perspective view of the spinal stabilization device depicted in FIG. 2 ;
FIG. 4 is a cross-sectional schematic view of the spinal stabilization device depicted in FIG. 3 ;
FIG. 5 is a perspective view of the spinal stabilization device shown in FIG. 3 , with one of the pedicle screws tilted relative to its position shown in FIG. 3 ;
FIG. 6 is a posterior elevation view of a human spinal column with two multi-level spinal stabilization devices according to an embodiment of the present invention implanted therein;
FIG. 7 is a perspective view of a stabilization device including an exemplary tensioning mechanism according to one embodiment of this invention; and
FIGS. 8-9 are views of the tensioning mechanism of FIG. 7 .
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION
FIG. 1 illustrates a human spinal column 2 including vertebrae 5 belonging to one of a cervical region a, a thoracic region b, a lumbar region c and a sacral region d of the spinal column 2 . Each vertebra 5 includes a superior end plate 6 and an inferior end plate 7 . An intervertebral disc is positioned in an intervertebral space 9 between adjacent vertebrae 5 .
FIG. 2 is a posterior elevation view of a patient's spinal column 2 into which a pair of spinal stabilization devices 100 according to the present invention are implanted between vertebrae L3 and L4. As shown in FIG. 2 , each of the stabilization devices 100 includes a pair of bone anchors, which in this case are pedicle screws 110 a and 110 b , a cord 120 , and a spacer 130 which, as discussed in more detail below, is substantially non-compressible and substantially rigid. As illustrated, each pedicle screw 110 a , 110 b is driven into a respective vertebra 5 . In the illustrated embodiment, the pedicle screw 110 a is implanted in the L3 vertebra, and the pedicle screw 110 b is implanted in the L4 vertebra. As will be understood by those skilled in the art, however, fixation of other vertebral pairs can be accomplished using the device of the present invention.
FIG. 3 is a perspective view of the stabilization device 100 according to one embodiment of the present invention. As illustrated in FIG. 3 , each pedicle screw 110 a and 110 b includes a head portion 140 with a top surface 142 , and a threaded shank portion 146 . As will be understood by those skilled in the art, the threaded shank portions 146 are adapted for implantation into a vertebra 5 of the patient. Each head portion 140 includes a threaded set screw 150 .
As illustrated, the spacer 130 includes end portions 132 and 134 , and is disposed between and in contact with the pedicle screws 110 a and 110 b . The cord 120 is a cord, cable or wire and is threaded through the spacer 130 and clamped to each pedicle screw 110 a and 110 b using the set screws 150 . In other embodiments, other clamping mechanisms may be used besides set screws 150 to secure the cord 120 in the pedicle screws 110 a and 110 b . When so clamped, the cord 120 serves to substantially prevent displacement of the screw heads 140 of the pedicle screws 110 a and 110 b away from each other. The spacer 130 operates to maintain the relative spacing of the pedicle screws 110 a , 110 b , and to substantially prevent displacement of the screw head 140 of the pedicle screws 110 a and 110 b toward each other.
In the illustrated embodiment, the cord 120 and the spacer 130 each have a generally cylindrical cross-sectional shape, although in other embodiments, they may have different shapes (e.g., rectangular, elliptical).
FIG. 4 is a cross-sectional view of the spinal stabilization device 100 . As shown in FIG. 4 , each screw head 140 includes a screw aperture 156 defined by an inner wall 158 . As discussed in more detail below, the aperture 156 operates as a cord receiving portion of the screw head 140 . A threaded hole 170 extends from the screw aperture 156 to the top surface 142 . As further shown, the spacer 130 includes a channel 160 positioned to generally align with the screw apertures 156 in the pedicle screws 110 a and 110 b such that the cord 120 can be extended through the screw apertures 156 and the channel 160 . As illustrated, in each of the pedicle screws 110 a , 110 b , the threads of the sets screws 150 match the threads of the threaded hole 170 such that each set screw 150 can be turned to advance into the screw apertures 156 to clamp the cord 120 against the inner wall 158 .
As further shown, the screw head 140 of each of the pedicle screws 110 a and 110 b may include generally spherical concave faces 180 and 184 disposed approximately 180 degrees apart. Additionally, each of the end portions 132 and 134 of the spacer 130 may include a generally spherical convex face 190 and 194 . As shown, the generally convex faces 190 and 194 are sized and shaped to mate with the generally concave faces 180 and 184 , respectively. In some embodiments (not shown), the faces 180 , 184 of the screw heads 140 may be generally spherical convex faces, and accordingly, the mating faces 190 , 194 of the spacer 130 have concave profiles. Alternatively, one of the faces 180 and 184 may be concave, and the other convex, in which case, the respective matching face 190 , 194 of the spacer 130 will be profiled to match as appropriate.
The illustrated configuration operates to optimize the contact stress and friction between the end portions 132 , 134 of the spacer 130 and the pedicle screw heads 140 . Additionally, this embodiment further permits three-dimensional angular displacement of the pedicle screws 110 a and 110 b relative to the spacer 130 by allowing the concave faces 180 and 184 to rotatably articulate along the convex faces 190 and 194 , respectively, of the spacer 130 . As further shown, to permit such angular displacement while minimizing wear to the metal cord 120 and preventing kinking of the cord 120 by the ends of the spacer 130 , the channel 160 may flare outward such that the channel 160 is larger near the end portions 132 and 134 than near the middle of the spacer 130 .
In yet other embodiments (not shown), the faces 180 , 184 , 190 , and 194 may be generally flat, thus shaped to permit relative rotation of the spacer 130 relative to the screw heads 140 in one dimension defined by the mating flat faces. In one such embodiment the screw faces 180 and 184 may not be perpendicular to the axis of the shank of the screw 146 , thereby permitting the device 100 to adapt to a patient's anatomy or pathology.
FIG. 5 is a perspective view of the stabilization device 100 in which the threaded shank portion 146 of the pedicle screw 110 b is tilted toward the pedicle screw 110 a . As shown, the longitudinal axis 250 of the pedicle screw 110 b is shown to have tilted toward the other pedicle screw 110 a by an angle φ from its original position 260 in which the shank portions 146 of the pedicle screws 110 a and 110 b are substantially parallel. As will be apparent to those skilled in the art, tilting of the pedicle screw 110 b as shown in FIG. 5 would not be possible if the interface between the spacer 130 and pedicle screw heads 140 were not the convex/concave configuration according to one aspect of the present invention. Tilting of the screw 110 a relative to the screw 110 b permits the stabilization device 100 , when implanted, to have the proper relative configuration with respect to anatomic features such as the vertebral end plates 6 and 7 .
The spacer 130 can be of any suitable material that is substantially rigid and substantially non-compressible. As used in this context, “rigid” means having a stiffness greater than that of the unreconstructed spine, and “non-compressible” means having a compressive strength sufficient to effectively prevent the heads 140 of the pedicle screws 110 , 110 b from being displaced toward each other under loads created by the patient's bodily movements when the device 100 is implanted as shown in FIG. 2 . Suitable materials include metals or alloys, such as titanium and its alloys, stainless steel, ceramic materials, rigid polymers including polyether-etherketone (PEEK™), and substantially rigid and non-compressible composite materials.
The cord 120 is generally configured and sized to be substantially resistant to strain or elongation under tensile loads that may be applied by the patient's bodily movements (e.g., bending and twisting of the spinal column). In one embodiment, the cord 120 may be a biocompatible metal (e.g., titanium and its alloys, stainless steel) wire or cable. Such a cord 120 can be tensioned much more tightly than a polymeric cord, thereby creating a stiffer stabilization system than existing dynamic systems. Thus, by varying tension in the cord 120 , the spinal stabilization device 100 can therefore achieve a wider range of flexibility than a device with a polymeric cord.
Thus, in the assembled and implanted state of the device 100 , the cord 120 effectively prevents displacement of the heads 140 of the pedicle screws 110 a , 110 b away from each other. The substantially incompressible spacer 130 substantially prevents movement of the heads 140 of the pedicle screws 110 a , 110 b toward each other.
In operation, the pedicle screws 110 a and 110 b are attached to their respective vertebrae, in the embodiment illustrated in FIG. 2 , the L3 and L4 vertebrae. The cord 120 is threaded though the screw apertures 156 and the spacer aperture 160 , with the spacer 130 sequenced between the pair of pedicle screws 110 a , 110 b . The cord 120 is then tensioned to a desired amount against the pedicle screws 110 a , 110 b so that the pedicle screws 110 a , 110 b are biased against and exert a compressive load on the spacer 130 and the concave faces 180 , 184 bear upon the convex faces 190 , 194 of the spacer 130 . The physician may vary or customize the stiffness of the stabilization device 100 by adjusting the tension applied to the cord 120 . In general, the greater the tension in the cord 120 , the more frictional resistance will impede articulation of the concave faces 180 and 184 along the convex faces 190 and 194 . Thus, the tension in the cord 120 in the assembled and implanted stabilization device 100 generally determines the overall stiffness of the device.
For example, the stabilization device 100 may be made substantially rigid by tensioning the cord 120 to a high degree. In such a case, the large frictional forces produced substantially prevent articulation of the convex faces 180 and 184 along the concave faces 190 and 194 of the spacer 130 . Alternatively, the physician may choose to apply a lesser degree of tension to the cord 120 , thus allowing articulation of the convex faces 180 , 184 along the concave faces 190 , 194 , which in turn creates a more flexible stabilization device 100 . Cord tension may also be varied from left side to right side. In such case, the cord 120 may be tensioned to a high degree between pedicle screws 110 a and 110 b on one side but tensioned to a lesser amount on the other side. This may be advantageous for patients requiring differing amounts of stabilization between left and right sides due to their disease (e.g., deformity or scoliosis). The amount of tension applied can thus be varied based on the particular patient's needs. In those cases where the tension in the cord 120 is minimal, or just enough to bring the various parts of the stabilization device 100 in contact, there may be very little resistance to articulation. In such cases the stabilization device 100 may predominantly provide the desired spacing between the vertebrae.
Tensioning of the cord 120 can be done, for example, by tightening one of the set screws 150 to clamp the cord 120 to one of the pedicle screws 110 a or 110 b and then tensioning the cord 120 against the other pedicle screw 110 a or 110 b . The set screw 150 of the second pedicle screw 110 a or 110 b is then tightened to clamp the cord 120 to that pedicle screw 110 a or 110 b . The tension in the cord 120 is thus maintained, and the pedicle screws 110 a , 110 b remain biased against the spacer 130 .
FIG. 6 depicts a posterior elevation view of a human spinal column with two multi-level spinal stabilization devices 300 according to an embodiment of the present invention implanted therein to stabilize the L3, L4 and L5 vertebrae. As shown in FIG. 6 , each stabilization device 300 includes three bone anchors, in this case pedicle screws 310 a , 310 b and 310 c , rigid spacers 320 a and 320 b , and a metal cord 330 . In the illustrated embodiment, the pedicle screws 310 a , 310 b and 310 c are implanted in the L3, L4, and L5 vertebrae, respectively. As will be apparent to those skilled in the art, the present invention also includes stabilization devices having more than two levels.
As illustrated, the spacer 320 a is disposed between the pedicle screws 310 a and 310 b , and the spacer 320 b is disposed between the pedicle screws 310 b and 310 c , and the cord 330 extends through the pedicle screws 310 a , 310 b , 310 c and the spacers 320 a and 320 b . The pedicle screws 310 a , 310 b , 310 c , the spacers 320 a , 320 b , and the cord 330 may be constructed and configured to operate substantially the same as the corresponding components described above with respect to the single level stabilization device 100 .
In one embodiment of the multi-level stabilization device 300 , the cord 330 may be clamped to each of the pedicle screws 310 a , 310 b and 310 c . Alternatively, the cord 330 may be clamped only to the two distal-most pedicle screws 310 a and 310 c . In one embodiment, the cord 330 may be tensioned to different degrees for different levels. For example, the segment of the cord 330 between the pedicle screws 310 a and 310 b be may be highly tensioned, while the segment of the cord 330 between the pedicle screws 310 b and 310 c may be tensioned to a lesser amount. As a result, the stabilization system 300 will be more rigid between the pedicle screws 310 a and 310 b than between 310 b and 310 c . Accordingly, fixation of the L3 and L4 vertebrae will be more rigid than fixation of the L4 and L5 vertebrae. As discussed above, the use of a metal cable or wire for the cord 330 allows for a much wider range of stiffness of the portion between any pair of pedicle screws as compared to an existing dynamic stabilization system. Thus, in a multi-level system, a stabilization device with a more patient-specific, side-specific, and level-specific stiffness profile can be achieved.
FIG. 7 is a perspective view of a stabilization device 100 including an exemplary tensioning mechanism 400 according to one embodiment of the present invention. The tensioning mechanism operates to permit the surgeon to apply the desired amount of tension to the cord 120 . As shown in FIGS. 7-9 , the tensioning mechanism 400 may include a cable tensioning nut 406 , a body 412 , a collet tightening nut 420 , and a collet 516 . (Tensioning mechanism 400 can be utilized for a cable 120 or cord 120 but is described in terms of a cable 120 ). The cable tensioning nut 40 may be that portion of the tensioning mechanism 400 that contacts the head portion 140 of the pedicle screw 110 . The collet tightening nut 420 may be positioned on the opposite side of the body 412 from the cable tensioning nut 406 . The collet 516 may be positioned around the cable 120 and in an interior portion of the body 412 . One end of the collet 516 may be contacted by the collet tightening nut 420 .
Each of the cable tensioning nut 402 , body 412 , and collet tightening nut 420 may further include flats 432 , 462 , and 482 , respectively, which are configured to be engaged by a tool, such as a wrench, for holding or turning that portion of the cable tensioning device 400 . Other tool engaging structures may likewise be incorporated in other designs. The collet tightening nut 420 may further include a cable exit hole 426 and the cable tensioning nut 406 may further include a cable entrance hole 436 and a pedicle screw contact surface 442 . The body 412 may further include external threads 466 that cooperate with internal threads on the cable tensioning nut 406 and external threads 490 that are engaged with internal threads on the collet tightening nut 420 . The body 412 may further include a shaped interior hollow portion (also known as a bore, cavity or passage) in a shape that tapers downwardly from the collet tightening nut 420 towards the cable tensioning unit 406 .
In operation, the cable tensioning device 400 is first slipped over the wire 120 until the pedicle screw contact surface 442 of the cable tensioning nut 406 contacts the head 140 of the pedicle screw 110 . The body 412 is then grasped by a wrench or other tool such that it can be prevented from twisting or moving around the cable 120 . The collet tightening nut 420 may then be grasped and rotated such that the collet 516 is pushed through the internal channel in the body 412 towards the cable tensioning unit 406 . Because of the tapering hollow portion in the body 412 the collet will be pressed, tightened or crimped inwards around the cable 120 . The collet tightening nut 420 may push the collet 516 into the hollow portion of the body 412 far enough to effectively secure the collet 516 , and therefore the body 412 , to the cable 120 in that position. It has been found that once the collet tightening nut 420 is tightened and the collet 516 is secured around the cable 516 , loosening the collet tightening nut 420 does not then allow the body 412 or the cable tensioning device 400 as a whole to slide over the cable 120 again. In alternative embodiments, however, such a releasable system may be realized.
The body 412 may then be again secured (or may still be secured from before) and the cable tensioning nut 406 may be rotated such that threads on the cable tensioning nut 406 interact with the external threads 466 of the body 412 so as to push the body 412 , collet 516 , and collet tightening nut 420 away from the head 140 of the pedicle screw 110 . This action, in effect, lengthens the cable tensioning device such that, because the body 412 and cable tensioning nut 406 are secured in relation to one section of the cable 120 by action of the collet 516 , the cable 120 is drawn through the head 140 of the pedicle screw 110 . The body 412 is moved by continued rotation of the cable tensioning nut 406 until the desired tension on cable 120 is achieved. The set screw 150 is then tightened in the head 140 of the pedicle screw 110 to secure the cable 120 in the desired position.
After the set screw 150 is tightened so as to secure the cable 120 , the cable tensioning nut 406 is then rotated in the opposite direction so as to provide some amount of slack in the cable 120 between the cable tensioning device 400 and the head 140 of the pedicle screw 110 . The cable 120 can then be cut between the cable tensioning device 400 and the head 140 so as to trim and remove the excess cable and the cable tensioning device 400 .
As may be appreciated, in further embodiments various cord tensioning devices may be employed, such as, for example, the use of pliers or other devices to pull the cord to the desired tension.
The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. Accordingly, the protection sought herein is as set forth in the claims below.
|
A device for spinal stabilization includes bone anchors, a metal cord, and a spacer. The materials of the cord and spacer are chosen to allow the physician to customize the stiffness of the stabilization device based on a particular patient's needs. Each bone anchor has a clamping mechanism for securing the cord to the bone anchor. In an assembled and implanted state of the device, the spacer is positioned between two neighboring bone anchors, thereby impeding the motion of the bone anchors toward each other; the cord is clamped to the bone anchors, thereby impeding the motion of the bone anchors away from each other. By increasing or decreasing the tension in the cord during implantation, the physician can create a stabilization device that is either relatively stiff or relatively flexible to accommodate the specific needs of the patient.
| 0
|
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of and priority to U.S. Provisional Patent Application No. 61/229,154, filed on Jul. 28, 2009, and herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
This invention relates in general to forming an adjustable foundation, and in particular, to a concrete slab foundation capable of being raised above the ground.
BACKGROUND OF THE INVENTION
Many structures have been built on foundations or slabs made of concrete poured on top of soil. Constant changes in the weather and moisture levels in the soil frequently cause damage to such a foundation. In many instances, the foundation may buckle or even crack. This phenomenon occurs for a variety of reasons, including uneven changes in the water content of supporting soils, uneven compacting of soils, and uneven loads being placed on soils. Over time, uneven movement in the soils under a foundation can cause a foundation to bend or crack.
Therefore, it would be desirable to provide a method and apparatus that would allow a foundation to be poured on top of soil and subsequently raised to a desired height to eliminate potential problems caused by soil movement and/or problematic soils.
SUMMARY OF THE INVENTION
An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation. At least one substantially vertical support member has a hollow body with first and second ends. The first end of the substantially vertical support member is in abutting contact with at least one support surface. At least one support sleeve surrounds the at least one support member. The at least one support sleeve is encased within the slab foundation and is capable of movement axially along the axis of the at least one support member. The at least one support sleeve has an opening through which the at least one support member extends. The opening is substantially geometrically complimentary to the at least one support member. The at least one vertical support member is capable of rotation relative to the at least one support sleeve to restrict the movement of the at least one support sleeve downward relative to the at least one vertical support member, thereby maintaining the height of the at least one support sleeve and the slab foundation relative to the at least one support surface.
An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation. At least one substantially vertical support member has a generally elliptical shaped hollow body with first and second ends. The first end of the at least one support member is in abutting contacting with at least one support surface. At least one support sleeve has a hollow body with inner and outer surfaces. The at least one support sleeve surrounds the at least one support member. The inner surface of the at least one support sleeve has a plurality of tabs extending along and radially inward from the inner surface at select intervals to thereby define a generally elliptical shaped opening. The opening is substantially geometrically complimentary to the at least one support member. The inner surface of the at least one support sleeve also has a plurality of apertures located in and extending therethrough. The outer surface of the at least one support sleeve has at least one reinforcing bar connected to and extending outwardly therefrom. The at least one support member initially extends through the substantially geometrically complimentary opening in the at least one support sleeve. The outer surface of the sleeve body and the at least one reinforcing bar are encased within the slab foundation. The at least one support sleeve and the slab foundation are capable of movement axially along the axis of the at least one support member. The at least one support member is capable of rotation relative to the at least one support sleeve to offset the at least one support member from the opening in the at least one support sleeve to thereby restrict the movement of the at least one support sleeve downward relative to the at least one support member. At least one lifting member is surrounded by the at least one support member. The at least one lifting member has a body with first and second ends, the first end being in abutting contact with the at least one support surface.
An embodiment of the present invention is directed to a method for forming a movable slab foundation. The method comprises placing a plurality of support surfaces below an intended slab foundation area. A plurality of support sleeves are placed in abutting contact with the plurality of support surfaces. The plurality of support sleeves have a geometrically shaped opening extending axially therethrough. A plurality of support members being geometrically complimentary to the openings are inserted into the openings and are placed within the plurality of support sleeves. The plurality of support members are slid down within the plurality of support sleeves and into abutting contact with the plurality of support surfaces. A slab foundation is formed such that it encases the plurality of support sleeves. The plurality of support sleeves are simultaneously lifted to move the slab foundation along the axes of the plurality of support members to a desired height. The plurality of support members are rotated relative to the plurality of support sleeves, thereby restricting the movement of the plurality of support sleeves downward relative to the plurality of support members and maintaining the desired height of the slab foundation.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the features and benefits of the invention, as well as others which will become apparent, may be understood in more detail, a more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof which are illustrated in the appended drawings, which form a part of this specification. It is also to be noted, however, that the drawings illustrate only various embodiments of the invention and are therefore not to be considered limiting of the invention's scope as it may include other effective embodiments as well.
FIG. 1 is a sectional view of a single slab support, illustrating a concrete pier and a support sleeve.
FIG. 2 is a sectional view of the support sleeve taken along the line 2 - 2 of FIG. 1 .
FIG. 3 is a sectional view of the single slab support with a support pipe and a lifting rod inserted and a lifting assembly connected.
FIG. 4 is a sectional view of the support sleeve and the support pipe taken along the line 4 - 4 of FIG. 3 .
FIG. 5 is a sectional view of the single slab support with the slab raised a distance above a ground surface.
FIG. 6 is a sectional view of the single slab support with the slab raised to a final height.
FIG. 7 is a sectional view of the support sleeve and support pipe taken along the line 7 - 7 of FIG. 6 .
DETAILED DESCRIPTION OF THE INVENTION
The present invention now will be described more fully hereinafter with reference to the accompanying drawings in which a preferred embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein; rather, this embodiment is 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 numbers refer to like elements throughout.
Referring to FIG. 1 , a foundation slab 11 may be used to support a house or other building or structure. In this embodiment, the slab 11 is of concrete and initially rests on a ground surface 17 and a support surface or pier 13 . The foundation or slab 11 is typically supported by a plurality of support surfaces or piers 13 , but for simplification purposes, the single pier 13 will be discussed. In this embodiment, the pier 13 is of concrete and has a base plate 15 embedded therein, such that at least the top or upper surface of the base plate 15 is exposed. In this embodiment, the base plate 15 is circular in shape, but in alternate embodiments may comprise different shapes, for example, a rectangle. In this embodiment, the base plate 15 has an anchor bolt 16 connected to it that extends a select distance into the concrete pier 13 . In alternate embodiments, other support members may be connected to the base plate 15 .
In this embodiment, the hole for the pier 13 is dug with a diameter such that the base plate 15 is fully encased within the concrete. Once the hole is dug as desired, the pier 13 is formed by pouring concrete into the hole. The base plate 15 is then embedded in the concrete of the pier 13 such that the top or upper surface of the base plate 15 is substantially parallel with the ground surface 17 . As previously discussed, in this embodiment, the anchor bolt 16 is connected to the base plate 15 and extends into the concrete of the pier 13 a distance below base the plate 15 .
In this embodiment, a cylindrical exterior pipe or support sleeve 19 has an outer diameter less than the diameter of the base plate 15 . The support sleeve 19 and the base plate 15 are sized such that the bottom surface of the support sleeve 19 is in supporting contact with the base plate 15 . The length of the support sleeve 19 may be less than or equal to the desired thickness of the concrete slab 11 . In this embodiment, the length of the support sleeve 19 is equal to the thickness of the concrete slab 11 . An inner surface 21 of the sleeve 19 has a plurality of support tabs 23 connected therein that extend along the inner diameter and radially inward a select distance. The support tabs 23 may be connected to the support sleeve 19 through various means, including, but not limited to welding and fasteners. As seen in FIG. 2 , in this embodiment, two support tabs 23 are positioned opposite from one another and extend around the inner surface 21 of the support sleeve 19 at select intervals.
Referring back to FIG. 1 , reinforcing bars (rebar) 25 are connected to the outer surface of the sleeve 19 . In this embodiment, a first leg 27 of the rebar 25 is connected to and extends outwardly and downwardly at an angle from the sleeve 19 . A second leg 29 of the rebar 25 is substantially perpendicular to the support sleeve 19 and extends between the first leg 27 and the sleeve 19 . The rebar 25 may be welded around the outer peripheries of the sleeve 19 at desired intervals. In an alternate embodiment, various reinforcing members may be connected to and extend outwardly from the outer peripheries of the sleeve 19 in various shapes and configurations.
A plurality of lift holes or apertures 33 are located in and extend radially outward through the inner surface 21 of the support sleeve 19 . In this embodiment, two lift holes 33 are positioned opposite from one another. The lift holes 33 are designed to accept a lifting device or lifting link.
The sleeve assembly 19 is positioned atop the base plate 15 . In an alternate embodiment, the lower end of the support sleeve 19 may be lightly tack welded to the base plate 15 . The concrete slab 11 is then poured, thereby embedding the rebar 25 and the sleeve assembly 19 within the slab 11 . The concrete may be kept from bonding to the concrete pier 13 and the base plate 15 by an optional bond breaker layer (not shown).
Referring to FIG. 3 , after the cement slab 11 has hardened, a support member or support pipe 35 having an elliptical shape ( FIG. 4 ) is inserted into the sleeve 19 and lowered until a lower first end portion makes contact with the base plate 15 . The elliptical shape of the support pipe 35 requires that it be properly oriented with respect to the support sleeve 19 to allow the support pipe 35 to pass by the tabs 23 on the inner surface 21 of the sleeve 19 without interference ( FIG. 4 ). The support pipe 35 is positioned such that the lower first end portion of the support pipe 35 rests on the base plate 15 . The support pipe 35 extends upwardly a selected distance from the base plate 15 . The length of supporting pipe 35 can be varied to accommodate various desired slab 11 heights. As shown in FIG. 4 , the support pipe 35 is elliptical in shape and is adapted to receive a lift bar 37 . The desired final height of the slab 11 is determined by the length of the support pipe 35 .
Referring back to FIG. 3 , a lifting member or solid lifting rod 37 , with a smaller diameter than the support pipe 35 is inserted into the support pipe 35 and lowered until it makes contact with the base plate 15 . The length of the lifting rod 37 can be calculated such that it may remain within the support pipe 35 once the slab 11 has reached its final desired height. Alternatively, the lifting rod 37 may be removed from the support pipe 35 once the slab 11 has reached its final desired height. After the lifting rod 37 is in place, a lift support plate 38 is positioned on the top of the support rod 43 . The support plate 38 has a plurality of apertures 39 located in and extending therethrough. A lifting device 41 is then mounted on the top of the support plate 38 . In this embodiment, the lifting device 41 is a hydraulic jack mounted on the top of the support plate 38 . A lift plate 43 is then positioned on top of the hydraulic jack 41 . The lift plate 43 has a plurality of apertures 45 located in and extending therethrough. The lift plate 43 is positioned such that the apertures 45 are in alignment with the apertures 39 in the support plate 38 .
Attachment members or attachment rods 47 are connected to the lift holes 33 in the sleeve 19 in order to lift the slab 11 to its desired height. In this embodiment, the attachment rods 47 contain threads in at least an upper portion thereof. The attachment rods 47 pass through the apertures 39 in the support plate 38 and the apertures 45 in the lift plate 43 . Nuts 48 are threaded onto upper portions of the attachment rods 47 located between the support plate 38 and the lift plate 43 . The nuts 48 may be adjusted once the slab 11 has been lifted to permit removal of the hydraulic jack 41 . Nuts 49 are threaded onto upper portions of the attachment rods 47 , above the lift plate 43 . The nuts 49 prevent the lift plate 43 from moving upward independently from the attachment rods 47 when the hydraulic jack 41 is activated.
Referring to FIG. 5 , hydraulic fluid pressure is applied to the jack 41 , causing the jack 41 to push the lift plate 43 and the attachment rods 47 upwards relative to the base plate 15 . The jack 41 moves the lift plate 43 and the attachment rods 47 upwards until the foundation slab 11 has been lifted above the ground 17 to the desired height. In the event that the hydraulic jack 41 needs to be removed during the lifting process, the nuts 48 can be tightened against the support plate 38 , thereby allowing the lifting device 41 and the lift plate 43 to be removed if necessary, while maintaining the height of the slab 11 .
Referring to FIG. 6 , once the slab 11 has reached its desired final height, the tabs 23 on the inner surface 21 of the sleeve 19 will be positioned above the support pipe 35 . In order to secure the slab 11 at the desired height, the support pipe 35 is then rotated such that the support tabs 23 are no longer offset from the elliptical shape of the support pipe 35 ( FIG. 7 ). Once the support tabs 23 are positioned above the support pipe 35 , and the support pipe 35 has been rotated to the proper position, the sleeve 19 , the slab foundation 11 , and the tabs 23 are lowered such that tabs 23 rest upon the support pipe 35 . Once the tabs 23 are securely resting upon the support pipe 35 , the attachment rods 47 , the support plate 38 , the hydraulic jack 41 , the lift plate 43 , and the lifting rod 37 ( FIG. 5 ) are removed.
Referring to FIG. 6 , the lifting rod 37 ( FIG. 5 ) may be removed if its length is greater than the final height of the slab 11 . Whether the lifting rod 37 is removed or remains within the support pipe 35 , once the slab 11 has reach its desired height, a cap 49 can be inserted into the sleeve 19 . In the event that the height of slab 11 needs to be adjusted, the cap 49 may be removed, the lifting rod 37 reinserted if not already in place, and the support plate 38 , the hydraulic jack 41 , the lift plate 43 , and the attachment rods 47 reconnected. Once the weight of the slab 11 is lifted from the support pipe 35 , the support pipe 35 is rotated such that the tabs 23 on the inner surface 21 of the sleeve 19 will not interfere with the support pipe 35 . The slab 11 is lowered to its original position. The support pipe 35 may be replaced with a supporting pipe with a length to accommodate the new desired height. Once the desired height has been reached, as previously illustrated, the slab 11 may be secured in place by rotating the new support pipe and lowering the weight of the slab 11 and the sleeve 19 onto the new support pipe. As previously discussed, the hydraulic jack 41 , the support plate 38 , the lift plate 43 , the attachment rods 47 , and the lifting rod 37 may then be removed and the cap 49 reinstalled in the sleeve 19 .
The invention has significant advantages. The invention provides a method and apparatus that allows a foundation to be poured on top of soil and subsequently raised to a desired height to eliminate potential problems caused by soil movement and/or problematic soils.
In the drawings and specification, there have been disclosed a typical preferred embodiment of the invention, and although specific terms are employed, the terms are used in a descriptive sense only and not for purposes of limitation. The invention has been described in considerable detail with specific reference to these illustrated embodiments. It will be apparent, however, that various modifications and changes can be made within the spirit and scope of the invention as described in the foregoing specification and as set forth in the following claims.
|
An embodiment of the system for forming a movable slab foundation as comprised by the present invention has a slab foundation, at least one substantially vertical support member, at least one support surface, and at least one support sleeve. The at least one support sleeve surrounds the at least one support member and is encased within the slab foundation and is capable of movement axially along the axis of the at least one support member. The at least one vertical support member is capable of rotation relative to the at least one support sleeve to restrict the movement of the at least one support sleeve downward relative to the at least one vertical support member, thereby maintaining the height of the at least one support sleeve and the slab foundation relative to the at least one support surface.
| 4
|
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit under 35 USC 119(e) of U.S. Provisional application No. 60/385,572 filed Jun. 5, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to the field of fluid behaviour, and in particular to a method of predicting in-flight icing of aerodynamic surfaces.
[0004] 2. Description of Related Art
[0005] Numerical modelling of the in-flight ice accretion process and its aerodynamic consequences has been performed for several decades to aid in the design of ice protection systems, and in the certification of aircraft for flight in icing conditions. There exists a diversity of advanced two- and three-dimiensional icing models that have been developed by various groups in a number of countries (e.g., Bourgault, Y., Beaugendre, H. and Habashi, W. G., 2000. Development of a shallow - water icing model in FENSAP - ICE . AIAA Journal of Aircraft, 37, 4: 640-646; Morency, F., Tezok, F. and Paraschivoiu, I., 1999 . Anti - icing system simulation using CANICE . AIAA Journal of Aircraft, 36, 6: 999-1006; Wright, W. B., 1995. Users manual for the improved NASA Lewis ice accretion code LEWICE 1.6. NASA CR-198355).
[0006] It is generally accepted that the existing models adequately predict rime ice formation, but that the prediction of glaze icing is still not sufficiently accurate (Kind, R. J., Potapczuk, M. G., Feo, A., Golia, C. and Shah, A. D., 1998. Experimental and computational simulation of in - flight icing phenomena . Progress in Aerospace Sciences, 34: 257-345). The icing community feels that only by advancing beyond the control-volume approach, which is used by vast majority of the existing models, can significant further progress be realised in the prediction of glaze icing (Gent, R. W., Dart, N. P. and Cansdale, J. T., 2000. Aircraft icing . Phil. Trans. R. Soc. Lond. A, 358 : 2873 - 2911 ).
[0007] An object of the invention is to overcome the control-volume limitation.
SUMMARY OF THE INVENTION
[0008] According to the present invention there is provided a method of modelling in-flight icing on an airfoil in a fluid stream, comprising the steps of identifying predetermined macroscopic physical variables relevant to ice formation in a particular fluid environment; calculating the behaviour of individual fluid elements based on said identified macroscopic physical variables taking into account the effect on collision efficiency of non-linear droplet trajectories and the distribution of heat transfer over the airfoil; and predicting ice accretion based on the calculated behaviour of said individual fluid elements.
[0009] The invention relies on a novel model, known as a morphogenetic model. In such a model, the behaviour of individual fluid elements is emulated, whereas in prior art icing models, prediction was based on the behaviour of the bulk mass flux of supercooled water droplets. The morphogenetic model is a combination of a particle trajectory model, which determines the trajectory and location of impact of fluid elements, and a random walk model, that predicts their motion, freezing and shedding. The morphogenetic discrete approach attempts to emulate the motion of individual droplets and the generation of a water film on the ice surface, along with subsequent freezing and the formation of a rough ice surface.
[0010] A significant feature of this type of model is that it allows the simulation and investigation of the stochastic variability of the accretion shape and mass, something that cannot be achieved with conventional continuous, deterministic models.
[0011] In a preferred embodiment, the influence of non-linear droplet trajectories on the local collision efficiency, and the distribution of heat transfer over the icing surface are also taken into account.
[0012] A great advantage of the morphogenetic model is that it can be readily adapted to simulate ice accretions forming on objects of complex, time varying geometry, where an analytical approach or even a current numerical approach may not be feasible.
[0013] The morphogenetic approach simulates numerically formation of ice accretion on any object exposed to icing conditions (e.g., fixed-wing aircraft, rotorcraft). The time evolution of the distribution of ice thickness is predicted as a function of the following atmospheric parameters: airstream velocity, airstream liquid water content, droplets volume median diameter, altitude and air temperature.
[0014] The novel method in accordance with the invention can take into account the variation of local cloud droplet efficiency and local heat transfer around an airfoil surface. It can be conveniently implemented in a computer with the results displayed on a suitable display, such as a computer monitor or printer.
[0015] The invention also provides a system for predicting in-flight icing on a surface in a fluid stream, comprising:
[0016] sensors for measuring predetermined macroscopic physical variables relevant to ice formation in a particular fluid environment;
[0017] a processor for calculating the behaviour of individual fluid elements based on said identified macroscopic physical variables taking into account the effect on collision efficiency of non-linear droplet trajectories and the distribution of heat transfer over the airfoil and predicting ice accretion based on the calculated behaviour of said individual fluid elements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings, in which:—
[0019] [0019]FIG. 1 shows the cumulative impinging (solid) and freezing (dashed) mass fluxes as a function of azimuth for three values of the maximum runback angle, α L . The maximum impingement angle, α M , is 50°.
[0020] [0020]FIG. 2 shows the maximum runback angle, α L , as a function of the runback factor, S, for three values of the maximum impingement angle, α M .
[0021] [0021]FIGS. 3 a to 3 c show a comparison between the ice accretion shapes predicted by the analytical (left-hand side) and morphogenetic (right-hand side) models. FIG. 3 a shows the maximum runback angle, α L =0°; FIG. 3 b the runback angle α L =50°, and FIG. 3 c shows the runback α L =90°.
[0022] [0022]FIG. 4 is similar to FIG. 3, but shows the maximum impingement angle α M =50°. FIG. 4 a shows a maximum runback angle, α L =0°, FIG. 4( b ) shows a maximum runback angle α L =50°; and FIG. 4( c ) shows a runback angle α L =90°.
[0023] [0023]FIG. 5 is similar to FIG. 3, but shows the maximum impingement angle α M =30°. FIG. 5 a shows the maximum runback angle, α L =0°; FIG. 5 b shows the runback angle α L =50°, and FIG. 5 c shows the runback angle α L =90°.
[0024] [0024]FIG. 6 shows the influence of the runback factor, S, on the ice mass predicted by the morphogenetic model (depicted by points), for three values of the maximum impingement angle, α M .
[0025] [0025]FIG. 7 shows the Frössling number ratio for three different heat transfer conditions (thick curves) and collision efficiency ratio multiplied by the four indicated values of the runback factor (thin curves) as a function of distance from the stagnation line of a NACA 0012 airfoil (see Eq. (24)).
[0026] [0026]FIG. 8 shows the maximum runback distance as a function of the runback factor for three distributions of the Frössling number. The circles correspond to the cases examined in FIGS. 9, 10, 11 and 12 .
[0027] [0027]FIG. 9 shows a comparison between ice accretion shapes predicted by the analytical and morphogenetic models for a runback factor of unity, when all impinging water freezes on impact. FIG. 9 a shows the analytical model; FIG. 9 b shows the morphogenetic model.
[0028] [0028]FIG. 10 shows a comparison between ice accretion shapes predicted by the analytical and morphogenetic models for a runback factor of 1.4 and a total water mass of 20 kg m −2 . FIG. 10 a shows an analytical model prediction for three heat transfer formulations: constant (homogeneous) Frössling number, smooth surface and rough surface. The thin solid line depicts the ice accretion when all impinging droplets freeze on impact. FIG. 10 b shows a morphogenetic model simulation for constant Frossling number. Four consecutive ice layers are distinguished, each corresponding to an additional total water mass of 5 kg m−2. FIG. 10 c shows a morphogenetic model simulation for a smooth surface. FIG. 10 d shows a morphogenetic model simulation for a rough surface.
[0029] [0029]FIG. 11 is the same as FIG. 10 but for a runback factor of 1.8.
[0030] [0030]FIG. 12 is the same as FIG. 10 but for a runback factor of 3.0.
[0031] [0031]FIG. 13 illustrates a simple ice prediction system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] In the description the following terms are employed:
c chord length (m) Fr Frössling number h convective heat transfer coefficient (Wm −2 K −1 ) k A thermal conductivity of air (W m −1 K −1 ) L F specific latent heat of freezing (J kg −1 ) m water mass flux along the surface (kg m −1 s −1 ) m F freezing mass flux (kg m −2 s −1 ) m W impinging water mass flux (kg m −2 s −1 ) m T total incoming water mass (kg m −2 ) M Fj freezing mass flux per unit length (kg m −1 s −1 ) M WVi impinging water mass flux on a vertical surface segment per unit length (kg m −1 s −1 ) Nu Nusselt number based on chord length P n freezing probability Q C convective heat flux (W m −2 ) Q E evaporative heat flux (W m −2 ) Q external heat flux, Eq. (5) (W m −2 ) Re Reynolds number based on chord length s distance from the stagnation line (m) s R maximum runback distance (m) S runback factor t time (s) T A air temperature (K) T S surface temperature (K) U uniform airstream velocity (m s −1 ) W airstream liquid water content (kg m −3 ) x, y spatial coordinates (m) α angle between horizontal and normal to airfoil surface (rad) β local collision efficiency Δl grid cell size (m) Δs average step length measured along the surface (m) — average value
[0033] subscripts
0 stagnation line v vertical i, j, n, m indicate location
[0034] In order to exemplify the invention, the formation of ice on a cylindrical object will first be considered. A complementary analytical model will be developed to verify the morphogenetic approach. The analytical model predicts a variety of accretion shapes as a function of a new dimensionless number, which is referred to as the runback factor. The analytical model is based on a conservation of mass equation that assumes the intercepted water mass forms an ice accretion of the shape determined by the heat balance equation, while the remaining unfrozen water is shed.
[0035] The objective is to predict the ice shape and mass on the upstream half of a non-rotating cylinder undergoing in-cloud icing. The model will assume wet icing conditions so that there is a surface flow of unfrozen liquid.
[0036] Consider the mass conservation equation for water flow over the upstream half of the cylinder, 0≦α≦1/2π, where α is the azimuthal angle measured from the stagnation line, and symmetry above and below the stagnation line is imposed. In order to keep the model simple, assume that once a droplet hits the cylinder surface without splashing, it either freezes or flows downstream along the surface under wind stress. It is further assumed that any unfrozen water is shed from the cylinder at α=1/2π. The variation of the water mass flux flowing along the cylinder surface is therefore determined by the difference between the impinging water flux and the freezing mass flux:
dm =( m W −m F ) Rdα (1)
[0037] where m is the water mass flux along the cylinder surface (kg m −1 s −1 ); mw is the impinging water mass flux (kg m −2 s −1 ); mF is the freezing mass flux (kg m −2 s −1 ); and R is the cylinder radius (m).
[0038] Non-linear trajectories of uniform size droplets are taken into account by using the following distribution of impinging water mass flux:
m W = U W β O cos ( π 2 α α M ) ( 2 )
[0039] where U is the uniform airstream velocity (m s −1 ); W is the airstream liquid water content (kg m −3 ); β O is the stagnation line collision efficiency; and α M is the maximum impingement angle (rad). The latter two parameters, β O and α M , are functions of the airspeed, droplet size and cylinder diameter.
[0040] When considering the heat balance for water flowing on the cylinder surface, it is assumed that the sensible and radiative heat fluxes are negligible in comparison with the convective and evaporative fluxes. In addition, analysis shows that for common icing conditions it ma be assumed, as a rough approximation, that the evaporative heat flux, Q E , is about 50% of the convective heat flux, Q C . Consequently:
m F = 1 L F ( Q C + Q E ) where Q E = 1 2 Q C ( 3 )
[0041] and L F is the specific latent heat of freezing (J kg −1 ).
[0042] The azimuthal variation of the convective heat flux is given by the expression:
Q C = Q O [ a - b cos ( c α ) ] ; Q O = k A ( T S - T A ) 2 R Re 0.5 ( 4 )
[0043] Here the coefficients a=2.4, b=1.2, and c=3.6; k A is the thermal conductivity of air (W m −1 K −1 ); T S is the surface temperature (K); T A is the air temperature (K); and Re is the cylinder Reynolds number.
[0044] Using Eqs. (2-4) and integrating Eq. (1) from the stagnation line, the following expressions are obtained for the water mass flux:
m ( α ) = 2 π U W β O R α M sin ( πα 2 α M ) - ( 5 a ) 3 Q O R 2 L F [ a α - b c sin ( c α ) ] for 0 ≤ α ≤ α M m ( α ) = 2 π U W β O R α M - ( 5 b ) 3 Q O R 2 L F [ a α - b c sin ( c α ) ] for α M ≤ α ≤ π 2
[0045] [0045]FIG. 1 shows the various regimes that are determined by the relation between the impingement and freezing terms in Eq. (5). The location where water stops flowing on the surface is given by the maximum runback angle, α L . It may be determined simply from Eq. (5) by solving m(α L )=0. The dotted line gives the potential cumulative ice mass, based on the heat transfer, formed between the stagnation line and the location α. The actual ice mass is clearly limited by the impinging water mass, so the former cannot exceed the latter. When the potential ice mass is less than the impinging water mass, the difference between the curves describing the cumulative impiniging water mass and the line describing the cumulative ice mass is the runback liquid mass flux at that location.
[0046] Ultimately, the shape of the resulting ice accretion is determined, in part at least, by the extent of the runback. In order to quantify this effect, we therefore define a dimensionless runback factor, S, as the ratio of the impinging mass flux to the freezing mass flux at the stagnation line:
S = m W ( α = 0 ) m F ( α = 0 ) = 2 U W β O L F 3 Q O ( a - b ) ( 6 )
[0047] When 0<S≦1, all impinging water freezes on impact and there is no surface flow of unfrozen liquid. When S>1, unfrozen water flows downstream from the stagnation line. The meaning of S may be interpreted from FIG. 1. It is the ratio of the slopes of the solid and dashed lines at α=0°. For a maximum runback angle, α L , of 0°, there is no water flow on the ice surface and the runback factor, S, is unity. For maximum water flow angles of 50°, and 90°, the runback factor is 3.14 and 5.95, respectively.
[0048] We now seek a general relation between α L , α M , and S. Using Eq. (5) with the condition m(α L )=0, and utilising Eq. (6), we obtain:
S = a α L - b c sin ( c α L ) 2 π α M ( a - b ) sin ( π 2 α L α M ) for 0 ≤ α L ≤ α M ( 7 a ) S = a α L - b c sin ( c α L ) 2 π α M ( a - b ) for α M ≤ α L ≤ π 2 ( 7 b )
[0049] [0049]FIG. 2 illustrates Eq. (7) graphically. An increase of the runback factor, arising from either a decreasing convective heat flux or an increasing impinging water flux at the stagnation line, leads to downstream displacement of the maximum runback point. As the maximum impingement angle decreases, while the runback factor is kept constant, the region of liquid flow also diminishes, since the total mass of impinging water is decreasing.
[0050] The total water mass impinging in the vicinity of the stagnation line, m O (kg m −2 ), is given by:
m O UWβ O t (8)
[0051] where t is the duration of the icing event (s).
[0052] We now seek an expression for the total mass intercepted by the cylinder, m TW , (kg m −1 ). Integrating Eq. (2) along the cylinder surface between the lower and upper maximum impingement azimuths, and using Eq. (8), gives:
m TW = ∫ - α M α M m W t R α = 4 π m O R α M ( 9 )
[0053] The total potential mass of ice accretion, m TF (kg m −1 ), that would form if there were an unlimited supply of water may be expressed as a function of the runback factor. Integrating the freezing mass rate, expressed by Eq. (3-4), along the front part of the cylinder and using Eq. (6) and (8) leads to:
m TF = ∫ - 0.5 π 0.5 π m F t R α = 2 m O R S ( a - b ) [ a π 2 - b c sin ( c π 2 ) ] ( 10 )
[0054] It should be kept in mind that the above analysis is valid only during the initial stages of ice formation on a cylinder, since we have implicitly assumed that the impinging flux and the freezing flux do not change with time or with the evolving geometry of the accreting ice, Eq. (1).
[0055] Since the validity of the analytical model is limited to the early stages of the ice growth when the newly formed ice accretion does not appreciably alter the cylindrical geometry, we will demonstrate that the morphogenetic model can be used to extend the simulations to longer icing events. In principle, the morphogenetic model predicts and accounts for the time evolution of the accretion shape. It is also particularly useful when simulating ice accretion on substrates of complex geometry, such as engine inlets and turbines. For simplicity, the morphogenetic model is constrained so that there is no recalculation of the airflow or the droplet trajectories during the ice growth. However, the model can incorporate time-dependent variation of the airflow around the evolving ice accretion and the consequent alteration of the droplet trajectories.
[0056] The morphogenetic model is a combination of a particle trajectory model, which determines the interception and impact location of fluid elements, and a random walk model, that emulates their motion and freezing along the substrate or ice surface. The model fluid elements may be imagined to consist of an ensemble of cloud droplets. A two-dimensional rectangular lattice defines the accretion domain.
[0057] We use a simple parameterisation for the local collision efficiency as a function of azimuthal angle:
β i = β O cos ( π 2 α i α M ) ( 11 )
[0058] Using this parameterisation, the fluid elements are placed randomly on the cylinder surface or on the existing ice structure, in such a way that their distribution accords with Equation (11). For now, it is also assumed that this parameterisation remains valid during the entire ice growth process. Consequently, this embodiment of the model is strictly applicable only when the accreted ice does not appreciably change the airflow and droplet trajectories. This restriction can however be relaxed by changing the model.
[0059] A fluid element begins its stochastic motion downstream along the surface, from its initial random impact location. At each step in the process, a random number is generated, and, according to its value, the element either freezes, moves downstream along the surface, or is shed once it reaches an azimuth of 90°. The model is sequential, so that as soon as a particular fluid element freezes or is shed from the structure, the behaviour of the next element is considered. Account is taken of the effect on collision efficiency of non-linear droplet trajectories, and allowing an azimuthal distribution of the heat transfer to the airstream. We will now derive a relation for the freezing probability as a function of the controlling macroscopic physical variables.
[0060] We consider the n th lattice site measured downstream from the stagnation line along the discretized cylinder or accretion surface. We consider that the mass flux of impinging water on a vertical surface segment, per unit length of the cylinder, M WVi (kg s −1 m −1 ), decreases from its maximum value at the stagnation line, to zero at the maximum impingement angle, α M . In addition, we take the impinging mass flux to be zero on horizontal surface segments, and also downstream from the maximum impingement angle. The freezing rate per unit length, M Fj (kg s −1 m 1 ), on the other hand, varies with location, and freezing may occur both on horizontal and vertical surface segments. Consequently, the mass of water entering the n th site is given by the difference between the total upstream impinging water mass,
∑ i = 1 m M WVi ,
[0061] (where “m” is the number of upstream vertical surface segments), and the total mass frozen upstream,
∑ j = 1 n - 1 M Fj .
[0062] It should be noted that m≦n, because the discrete approximation of the cylinder or accretion surface by the boundaries of square grid cells, produces a staircase surface profile, with some grid sites where fluid elements cannot impinge directly (e.g. horizontal surface segments). Since the freezing rate at the n th site is M Fn , we set the freezing probability equal to the ratio of the mass frozen at site “n” to the incoming liquid mass at the site:
P n = M Fn ∑ i = 1 m M WVi - ∑ j = 1 n - 1 M Fj ( 12 )
[0063] The morphogenetic model values of M MVi and M Fi may be related to the physical value of the impinging water mass flux on vertical surfaces, m WVi , and the freezing rate, m Fj , as follows:
M WVi =m WVi Δl M Fj =m Fj Δs (13)
[0064] where m WVi is related to the impinging water mass flux according to m Wi =m WVi cos(α i ). The dimension Δl is the grid cell size and Δs is the average step length measured along the surface. The relation between these two quantities iS Δs=0.25 πΔl. Substituting the expressions from Eq. (13) into Eq. (12) gives a relation for the freezing probability at location “n”:
P n = 1 4 π ∑ i = 1 m S i , n - S 1 , n ∑ j = 1 n - 1 1 S 1 , j
where S i . j = m WVi m Fj ; n = 1 , 2 , … , n t ; m ≤ n ( 14 )
[0065] where n t is the total number of sites measured along the actual surface from the stagnation line to the shedding location (n t =2 R Δl −1 for a bare cylinder). The local runback factor, S i,j may be expressed using Eqs. (2-4) and (6) as a function of the runback factor (at the stagnation line) and the azimuth:
S i , j = U W β O cos ( π 2 α i α M ) cos ( α i ) 3 Q O 2 L F [ a - b cos ( c α j ) ] = S cos ( π 2 α i α M ) cos ( α i ) a - b a - b cos ( c α j ) ( 15 )
[0066] Simulations of fluid element motion and freezing or shedding are performed consecutively for the total number of fluid elements determined by the specified total intercepted mass flux. Prior to launching a new fluid element, the distribution of the freezing probability along the evolving surface (as nt increases) is recalculated using Eq. (14) and (15). In order to accomplish this task, the accretion is divided into upper and lower sections by a horizontal plane passing through the cylinder centre, and the distribution of the freezing probability is calculated separately for each side. This recalculation of the distribution of freezing probability, prior to considering the motion of the next fluid element, allows the effect of the changing accretion shape on the runback and freezing processes to be taken into account.
[0067] Each fluid element ends its motion either by freezing or by shedding. When a fluid element freezes, a “cradle” location is sought in the neighbourhood of the freezing grid cell, and this cradle location becomes the final resting place of the frozen element. This neighbourhood is a square centred on the freezing grid cell with a side length of 9Δl. Any unfrozen fluid elements are shed from the cylinder when they reach an azimuthal angle of ±90° from the stagnation line.
[0068] The analysis of the analytical model allows identification of the following three governing parameters: the runback factor, S, the maximum impingement angle, α M , and the total water mass impinging in the vicinity of the stagnation line, m O . However, Eq. (7) shows that S, α M , and α L are correlated, and hence we may replace the runback factor, S, with the maximum runback angle, α L , and analyse the icing process as a function of aL, α M and m O . On the one hand, the choice of S as the governing parameter seems to be more physically correct, since S is related directly to the physical parameters, Eq. (6). On the other hand, α L has an obvious visual interpretation. Consequently, we will use either or both parameters as the need arises.
[0069] The ice shapes predicted by the analytical and morphogenetic models are presented in FIGS. 3, 4, and 5 , side by side, for the same values of the governing parameters. The following values have been chosen to illustrate the range of possible conditions: α M =90°, 50°, and 30°; α L =0°, 50°, and 90° (with appropriately varying S); and m O =2.5, 5.0, 7.5, 10 kg m −2 . We examine the accretion on a cylinder of radius 25 mm, and an ice density of 900 kg m −3 is assumed, consistent with glaze icing. The morphogenetic model simulations are performed on a two-dimensional lattice with a grid size, Δl, of 1 mm, consisting of 40 (horizontal) by 80 (vertical) cells. The total incoming water mass is divided into a set of fluid elements, each occupying 1 mm 2 after freezing. Four different symbols are used to distinguish consecutive ice layers predicted by the morphogenctic model.
[0070] [0070]FIG. 3 shows results for horizontal, straight line droplet trajectories, α M =90°, and for three values of the maximum runback angle 0°, 50°, and 90°, which correspond to runback factors of 1.00, 2.28, and 3.30, respectively (see FIG. 2). Four consecutive ice layers are distinguished, each corresponding to m O =2.5 kg m −2 of water mass impinging in the vicinity of the stagnation line. The maximum impingement angle, α M , is 90° and the cylinder radius, R, is 25 mm. The solid squares represent the cylinder surface in the morphogenetic model.
[0071] [0071]FIG. 3 a shows the results when cloud droplets freeze instantly upon impingement, α L =0°. The results of the analytical model are based on Eq. (2) and it is assumed that the ice grows radially. In this particular case, the radial growth assumption leads to rather unrealistic ice shapes, characterised by varying vertical cross-sections and increasing horizontal dimensions. On the contrary, the ice should grow only forward with constant vertical cross-section. The morphogenetic model prediction shows these expected ice growth characteristics. The morphogenetic model also displays random features of the ice structure such as the lack of perfect symmetry about the horizontal surface passing through the cylinder centre. The total ice mass predicted by the analytical- and morphogenetic models is shown as a function of the runback factor in FIG. 6, where the solid horizontal lines correspond to the total mass intercepted by the cylinder as predicted by the analytical model, Eq. (9). The solid curve represents the maximum potential ice mass predicted by the analytical heat balance equation, Eq. (10). The total water mass impinging in the vicinity of the stagnation line, m O =10 kg m −2 , and the cylinder radius, R=25 mm. The mass obtained by the morphogenetic model (point for S=1) agrees with the analytically calculated intercepted mass (horizontal line).
[0072] [0072]FIG. 3 b shows results for a maximum runback angle of 50° corresponding to a runback factor of 2.28. In this case, unfrozen water flows from the stagnation line to an azimuth of 50° on the upper and lower cylinder surface. Consequently, in this region, the analytical distribution of the ice thickness is determined by the heat balance formulation, and the ice thickness follows the azimuthal angular dependence of the first part of Eq. (4). There is a discontinuity at the maximum runback location, since downstream from this point, the impinging droplets freeze instantly and the ice growth is determined by Eq. (2). Since in the analytical model the ice shape calculations are based on the initial growth rate, the model predicts unrealistic ice formation behind the ice horns. The ice growth there should diminish with time due to the shadowing effect of the horns. The morphogenetic model properly simulates this time-dependent shadowing effect. Moreover, the overall ice shape predicted by the morphogenetic model agrees well with the analytical model prediction.
[0073] Results for the critical case, when unfrozen water flows over the entire upstream half of the cylinder, and freezes at α=±90°, are shown in FIG. 3 c . Here, the analytical model prediction is solely determined by the heat balance equation. The morphogenetic model gives, overall, a similar ice thickness distribution, but, due to the shadowing effect, there is less ice forming near α=±90°. When the runback factor is less than the critical value of 3.30, the total ice mass is independent of the runback factor, since there is no water shedding. However, greater values of the runback factor lead to water shedding at α=±90° and the ice mass then decreases with increasing runback factor, FIG. 6. It is apparent that the ice mass predicted by the two models is approximately the same. The stochastic variability of the morphogenetic model's prediction is due to its inherent randomness.
[0074] We now consider cases where the maximum impingement angle is 50°, FIG. 4. The water mass impinging in the vicinity of the stagnation line, m O , is assumed to be the same as for the cases of FIG. 3, but the total impinging mass on the cylinder is smaller by 44.4%, Eq. (9), FIG. 6. When the maximum runback angle, α L , iS 0° (corresponding to S=1.00), there is no water flow on the surface and the two models predict similar ice shapes, FIG. 4 a . An increase of α L to 50° (corresponding to S=3.14), FIG. 4 b , leads to water flow on the surface, and the analytical model predicts horns with abrupt edges. The morphogenetic model predicts a similar accretion shape, but with less pronounced horns. When the maximum runback angle is 90° (corresponding to S=5.95), FIG. 4 c , the ice shapes predicted by the two models are quite similar.
[0075] [0075]FIG. 5 shows model results for a maximum impingement angle of 30°. Values of the maximum runback angle of 0°, 500 , and 900 , correspond to runback factors of 1.00, 5.24, and 9.91, respectively. As before, there is overall agreement between the accretion shapes predicted by the two models, with differences similar to those discussed in the analysis of FIG. 4. When water is not shed from the cylinder, the total ice mass remains constant, but it decreases with decreasing α M , FIG. 6. When water is shed, the ice mass is not a function of the maximum impingement angle, but is instead determined by the integrated heat flux, Eq. (10).
[0076] The morphogenetic model simulates ice accretion on a cylinder in good agreement with the analytical model. The morphogenetic model is able to account for the influence of non-linear droplet trajectories and the spatial distribution of the heat transfer. The advantage of the morphogenetic model is that it can simulate not only the initial ice growth, like the analytical model, but it can also handle the evolution of the accretion shape. In addition, the power of the morphogenetic model is that it is not limited to simple geometries.
[0077] In second embodiment, the morphogenetic model will now be considered in relation to an airflow, and in particular an NACA 0012 airfoil undergoing in-cloud icing. We will make a number of simplifying assumptions, some of which have a larger impact on the accuracy of the simulation, in the interest of achieving an analytical solution. We begin by considering the mass conservation equation for the liquid film flow over the airfoil. We assume that the angle of attack is zero and consequently symmetry above and below the stagnation line is imposed. To further simplify the model, we assume that once a droplet hits the airfoil surface without splashing, part of it may freeze in situ and part will flow downstream along the surface under wind stress, where further freezing may occur. The variation of the water mass flux flowing along the airfoil surface is therefore determined by the difference between the impinging water flux and the freezing mass flux:
dm=m W ds−m F ds (16)
[0078] The locally impinging water flux is calculated using the relation:
m W =UW β( s ) (17)
[0079] The local collision efficiency was numerically determined for a NACA 0012 airfoil with chord length of 0.9144 m, airstream velocity of 44.7 m s −1 , and median volumetric droplet diameter of 20 μm.
[0080] When considering the heat balance for water flowing on the airfoil surface, we assume that the sensible and radiative heat fluxes are negligible in comparison with the convective and evaporative fluxes. In addition, a simple analysis shows that for some common icing conditions, it may be assumed, as a rough approximation, that the evaporative heat flux is about 50% of the convective heat flux. Consequently, we take:
m F = 1 L F ( Q C + Q E ) where Q E = 1 2 Q C ( 18 )
[0081] The distribution of the convective heat flux along the airfoil may be expressed in terms of the Frössling number which is related to the Nusselt and Reynolds numbers:
Fr = Nu Re and Nu = hc k A ( 19 )
[0082] Consequently:
m F = 3 2 Q L F Fr ( s ) ; Q = k A ( T S - T A ) c Re ( 20 )
[0083] Three distributions of the Frössling number are considered: constant Frössling number; smooth airfoil surface; rough airfoil surface. The corresponding experimental distributions may be approximated, respectively, by the following relations:
Fr = 4.5 Fr = 4.5 e - 35 s Fr = { 4.5 + 125 s when 0 ≤ s < 0.02 m 7.0 + e - 28 ( s - 0.02 ) when s ≥ 0.02 m ( 21 )
[0084] Using Eqs. (17) and (20) and integrating Eq. 16 from the stagnation line, we obtain the following expressions for the water mass flux:
m ( s ) = UW ∫ 0 s β ( s ) s - 3 Q 2 L F ∫ 0 s Fr ( s ) s ( 22 )
[0085] Ultimately, the shape of the resulting ice accretion is determined, in part at least, by the extent of the runback. In order to quantify this effect, we define a dimensionless runback factor as the ratio of the impinging mass flux to the freezing mass flux at the stagnation line:
S = m W ( s = 0 ) m F ( s = 0 ) = 2 UW β 0 L F 3 QFr 0 ( 23 )
[0086] where β 0 and Fr 0 are respectively the local collision efficiency and the Frössling number at the stagnation line. When 0<S≦1, all impinging water freezes on impact at the stagnation line. When S>1, unfrozen water flows downstream from the stagnation line. Using the definition of the runback factor, Equation (22) may be rewritten:
m ( s ) = 3 Q 2 L F Fr 0 s [ S β _ ( s ) β 0 - Fr _ ( s ) Fr 0 ] ( 24 )
[0087] where {overscore (β)}(s) is the average collection efficiency and {overscore (Fr)}(s) is the average Frössling number, both averaged over the airfoil surface from the stagnation line to the point s. FIG. 7 displays the variation along the airfoil surface of the two dimensionless terms in brackets in Eq. (24): first, the product of the runback factor and the collision efficiency ratio and second, the Frössling number ratio. When the first term exceeds the second, water flows along the airfoil surface. At the point where the curves intersect, water flow stops. We call this location the maximum runback distance, s R .
[0088] We now seek a general relation between the maximum runback distance and the runback factor, for the three assumed Frössling number distributions. Using Eq. (24) with the condition m(s R )=0, we obtain:
s β _ ( s R ) β 0 = Fr _ ( s R ) Fr 0 ( 25 )
[0089] [0089]FIG. 8 illustrates the solution of Eq. (25) graphically. An increase of the runback factor, arising from either a decreasing convective heat flux or an increasing impinging water flux at the stagnation line, leads to downstream displacement of the maximum runback location. For the smooth surface formulation, when the runback factor is equal to unity, all impinging droplets freeze at the stagnation line, but there is not enough heat removed between the stagnation line and the location 16 mm downstream, and consequently, water flows within this region (see also FIG. 7). In addition, since the smooth surface is characterised by the least efficient heat exchange, the maximum runback location moves rapidly away from the stagnation line as the runback factor increases. For a runback factor less than 4.6, the extent of the liquid flow is a minimum for the rough case. However, for very wet cases characterised by high values of the runback factor, S>4.6, the maximum runback distance is a minimum for the constant Frossling number case.
[0090] Finally, we define the “total incoming water mass”, m T (kg m −2 ) to be:
m T =UWt (26)
[0091] This is the maximum possible impinging water mass, which would prevail if β were unity everywhere.
[0092] It should be kept in mind that the above analysis is valid only during the initial stages of ice formation on an airfoil, since we have implicitly assumed that the impinging flux and the freezing flux do not change with time or with the evolving geometry of the accreting ice, Eq. (16).
[0093] The airflow around the airfoil and the droplet trajectories have not actually been calculated. Instead, a simple parameterisation is used for the local collision efficiency as a function of distance from the stagnation line measured along the airfoil:
β i =β( s i ) (27)
[0094] The fluid elements impact randomly on the airfoil surface or on the existing ice structure, in such a way that their distribution accords with Equation (27). For now, it is further assumed that-this parameterisation remains valid during the entire ice growth process. Consequently, the model in its present form is strictly applicable, only when the accreted ice does not appreciably change the airflow and droplet trajectories. This condition, too, will be relaxed in future versions of the model.
[0095] A fluid element begins its stochastic motion downstream along the surface, from its initial random impact location. At each step in the process, a random number is generated, and, according to its value, the element either freezes or moves downstream along the surface. The model is sequential, so that as soon as a particular fluid element freezes, the behaviour of the next element is considered. We will now derive a relation for the freezing probability as a function of the controlling macroscopic physical variables. Here we recall that the angle of attack is taken to be zero, and the free stream velocity is assumed to be horizontal.
[0096] We examine the n th lattice site measured downstream from the stagnation line along the discretized airfoil or accretion surface. We consider that the mass flux of impinging water on a vertical surface segment, per unit length of the airfoil, M WVi , decreases from its maximum value at the stagnation line to zero. In addition, we take the impinging mass flux to be zero on horizontal surface segments, and also on all segments downstream from the maximum impingement location. The freezing rate per unit length, M Fj , varies with location, and freezing may occur both on horizontal and vertical surface segments. Consequently, the mass of water entering the n th site is given by the difference between the total upstream impinging water mass,
∑ i = 1 m M WVi ,
[0097] (where “m” is the number of upstream vertical surface segments), and the total mass frozen upstream,
∑ j = 1 n - 1 M Fj ,
[0098] It should be noted that m≦n, because the discrete approximation of the airfoil or accretion surface by the boundaries of square grid cells, produces a staircase surface profile, with some grid sites where fluid elements cannot impinge directly (e.g. horizontal surface segments). Since the freezing rate at the n th site is M Fn , we set the freezing probability equal to the ratio of the mass frozen at site “n” to the incoming liquid mass at the site:
P n = M Fn ∑ i = 1 m M WVi - ∑ j = 1 n - 1 M Fj ( 28 )
[0099] The morphogenetic model values of M WVi and M Fi may be related to the physical value of the impinging water mass flux on vertical surfaces, m WVi , and the freezing rate, m Fj , as follows:
M WVi =m WVi Δl;M Fj =m Fj Δs (29)
[0100] where m WVi is related to the impinging water mass flux according to m Wi =m WVi cos(α i ) where α i is the angle between direction of the mean impingement and the normal to the airfoil surface. The dimension Δl is the grid cell size and Δs is the average step length measured along the surface. The relation between these two quantities is Δl=1.27Δs. Substituting the expressions from Eq. (29) into Eq. (28) gives a relation for the freezing probability at location “n”:
P n = 1 1.27 ∑ i = 1 m S i , n - S 1 , n ∑ j = 1 n - 1 1 S 1 , j where s i , j = m WV i m Fj ; n = 1 , 2 , … , n t ; m ≤ n ( 30 )
[0101] where n t is the total number of segments measured along the discrete airfoil surface, from the stagnation line to the edge of the domain. The local runback factor, S i,j may be expressed using Eqs. 17 and 20 as a function of location and the runback factor at the stagnation line:
S ij = UW β ( s i ) cos ( α i ) 3 Q 2 L F Fr ( s j ) = S β ( s i ) β 0 1 cos ( α i ) Fr ( s j ) Fr 0 ( 31 )
[0102] Simulations of fluid element motion and freezing are performed consecutively for the total number of fluid elements determined by the specified total intercepted mass flux. Prior to launching a new fluid element, the distribution of the freezing probability along the evolving surface is recalculated using Eq. (30 and (31). In order to accomplish this task, the accretion is divided into upper and lower sections, and the distribution of the freezing probability is calculated separately for each side. This recalculation of the distribution of freezing probability, prior to considering the motion of the next fluid element, allows the effect of the changing accretion shape on the runback and freezing processes to be taken into account.
[0103] Each fluid element ends its motion either by freezing or by leaving the domain, while still in a liquid state. When a fluid element freezes, a “cradle” location is sought in the neighbourhood of the freezing grid cell. This neighbourhood is a square centred on the initially determined freezing point with side equal to 9Δl (10) . The freezing fluid element is moved to the empty cell within this area where it will have the maximum number of occupied neighbours. If there is more than one such location, the final site is chosen randomly from among them.
[0104] The influence of the determining parameters on the accretion process, as predicted by the analytical and morphogenetic models for an airfoil section will now be discussed. The analysis will be performed as a function of the runback factor, assuming three heat transfer formulations: constant Frössling number, smooth airfoil surface, and rough airfoil surface. The governing equations for those three cases are given by Eq. (21).
[0105] The ice accretion on a NACA 0012 airfoil with 0.9144 m chord length will be examined. The ice shapes predicted by the analytical and morphogenetic models are presented for a total incoming water mass of 5, 10, 15 and 20 kg m 2 ; Different shading is used to distinguish the four consecutive ice layers predicted by the morphogenetic model. An ice density of 900 kg m −3 is assumed, consistent with glaze icing. The morphogenetic model simulations are performed on a two-dimensional lattice with a grid size, Δl, of 0.5 mm, consisting of 200 by 200 cells. The total incoming water mass is divided into a set of fluid-elements, each occupying 0.25 mm 2 after freezing.
[0106] [0106]FIG. 9 shows ice shapes predicted by the analytical and morphogenetic models, assuming that all impinging liquid freezes on impact. This situation corresponds to a runback factor less than or equal to unity. In addition, the heat removed from the ice surface downstream from the stagnation line is large enough for instantaneous droplet freezing. The results of the analytical model are based on Eq. (17), where we assume that the ice growth direction is perpendicular to the airfoil surface. While Eq. (17) is, strictly speaking, valid only at the initial time, it is applied for the entire duration of the icing event. This assumption leads to an overestimation of the ice accretion size since the ice surface area increases during the ice growth, while the impingement limits are kept fixed.
[0107] The four solid lines in FIG. 9 a depict the ice accretion shape for a total incoming water mass of 5, 10, 15 and 20 kg m −2 . The morphogenetic model simulation for the same conditions is shown in FIG. 9 b . There is an overall agreement between the morphologies of both icing predictions. The morphogenetic model exhibits certain stochastic features of the ice structure such as roughness and a lack of perfect symmetry about the airfoil's horizontal axis of symmetry. The stochastic variability of the morphogenetic model's prediction is due to its underlying randomness.
[0108] When the runback factor exceeds unity, there is not enough heat removed at the stagnation line for all the impinging liquid to freeze, and water starts to flow downstream along the airfoil. The analytical model predictions for a runback factor of 1.4 and a total incoming water mass of 20 kg m 2 are displayed in FIG. 10 a . The three thick curves represent ice shapes for the different heat transfer formulations. For comparison purposes, the final ice shape for the instantaneous freezing (dry icing) case is also shown and depicted by a thin curve. Since the runback factor is the same for all three heat transfer cases, the ice thickness at the stagnation line remains constant. This is because the runback factor is the ratio of the maximum ice thickness at the stagnation line to its actual value (see Eq. 23). Unfrozen water flows from the stagnation line along the upper and lower airfoil surfaces. Consequently, in this region, the analytical model prediction is solely determined by the heat balance equation, and the ice thickness follows the Frössling number given by Eq. 21. There is a discontinuity at the maximum runback location, since downstream from this point, the impinging droplets freeze instantly and the ice growth is determined by Eq. 17. Since the analytical model's ice shape calculations are based on the initial growth rate, the model predicts unrealistic ice formation behind the ice horns. The ice growth there should diminish with time due to the shadowing effect of the horns. The maximum runback location is a function of the heat transfer formulation (see FIG. 8), and this is reflected in the shape and extent of the ice accretion.
[0109] The morphogenetic model results for the three heat transfer formulations are shown in FIGS. 10 b , 10 c , and 10 d . To show the time evolution of the accretion, four consecutive ice layers are depicted. For homogeneous heat transfer conditions, FIG. 10 b , the ice thickness is approximately constant in the runback region. Downstream from the maximum runback location, impinging droplets freeze instantly and the resultant ice thickness reflects the distribution of the collection efficiency. While there is an overall agreement between the two models, the morphogenetic model better emulates the time-dependent features.
[0110] For the smooth surface formulation, FIG. 10 c , the water flows over the entire ice surface and the whole ice shape is governed by the distribution of the Frössling number. For the case of a rough surface, FIG. 10 d , the maximum ice thickness develops downstream from the stagnation line, leading to ice horn formation. The ice thickness at the stagnation line and the overall ice shape and extent agree well with the analytical model prediction. However, the morphogenetic model simulates a time-dependent shadowing effect.
[0111] An increase of the runback factor is associated with less efficient water freezing, and this is reflected in an increasing extent of the ice accretion forming on the airfoil. The analytical model predictions for a runback factor of 1.8 are shown in FIG. 11 a . The ice thickness at the stagnation line is the same for all three heat transfer cases, since the relation between the actual and maximum ice thickness at the stagnation line is given by the runback factor.
[0112] The maximum runback location is shown in FIG. 8, with the corresponding analytical ice shapes displayed in FIG. 11 a . The time evolution of the ice shapes simulated by the morphogenetic model, for the three heat transfer formulations, is shown in FIGS. 11 b , 11 c , and 11 d . When the heat transfer conditions are homogeneous, FIG. 11 b , the ice thickness remains approximately constant along the airfoil. For the smooth surface, FIG. 11 c , the ice thickness gradually decreases from a maximum value at the stagnation line. For the rough case, FIG. 11 d , the thickness of the ice accretion along the airfoil initially increases then quickly diminishes to zero. A comparison of FIG. 11 with the corresponding FIG. 10 shows that an increase of the runback factor leads to a decrease of the ice thickness at the stagnation line, and to downstream displacement of the accretion's centre of mass.
[0113] An even greater increase of the runback factor continues to decrease the overall ice thickness and to increase the ice accretion's extent. The analytical model prediction for a runback factor of 3 is shown in FIG. 12 a . For the smooth surface, there is insufficient heat removed from the surface to freeze all the impinging water (see also FIG. 8). The analytical model predicts that only 63% of the impinging water mass freezes within the model domain depicted in the figures, while the rest leaves the domain. For homogeneous heat transfer, FIG. 12 b , the morphogenetic model predicts an approximately constant ice thickness. For a smooth surface, FIG. 12 c , the morphogenetic model predicts a gradual decrease of the ice thickness, while 68% of the impinging mass freezes inside the model domain. For the rough surface, both models predict a maximum ice thickness away from the stagnation line.
[0114] The morphogenetic model can simulate ice accretion on airfoils. The airflow, droplet trajectories, and the distribution of the convective heat transfer coefficient can be recalculated as the ice accretion evolves with time.
[0115] The morphogenetic model is a combination of a particle trajectory model, which determines the interception and impact location of fluid elements, and a random walk model, that emulates their motion and freezing along the airfoil or ice surface. The model fluid elements may be imagined to consist of an ensemble of cloud droplets, all of which undergo identical histories. A two-dimensional rectangular lattice defines the accretion domain, although extension to three dimensions is straightforward but computationally demanding. In principle, the morphogenetic model predicts and accounts for the time evolution of the accretion shape. Consequently, it can be particularly useful when simulating ice accretion on substrates of complex geometry, such as engine inlets and turbines.
[0116] The above results show that the morphogenetic model simulates ice accretion on an airfoil, in good agreement with an analytical model based on conservation of mass and heat balance equations. The morphogenetic model can simulate not only the initial ice growth, like the analytical model, but also the evolution of the accretion shape. However, the real power of the morphogenetic model for aircraft icing is that it can be applied to icing in complex three-dimensional geometries.
[0117] A significant feature of the model is that it allows the investigation of the stochastic variability of the accretion shape under constant external conditions. This allows calculations of error bars on the model predictions, something that cannot be achieved with existing continuous, deterministic models. Such error bars are helpful later when making comparisons with experimental results. The morphogenetic model can be used to simulate more accurately the time-dependent formation of ice accretion on airfoils, by recalculating the airflow, droplet trajectories, and the distribution of the convective heat transfer coefficient, as the ice accretion evolves with time.
[0118] In a practical application of morphogenetic modelling, as shown in FIG. 13, sensors 10 continually monitor the significant parameters, namely airstream velocity, airstream liquid water content, droplet volume median diameter, altitude and air temperature. This data is digitized and fed into a computer 12 or signal processor to predict the expected ice growth on the airfoil surface based on the morphogenetic model described above. The results can be used to improve in-flight safety by giving the pilot warning of imminent icing conditions. The morphogenetic model can also be used to improve the design of airfoils.
[0119] A detailed discussion of in-flight icing phenomena and the applications of computational models is disclosed in R. J. Kind, M. G. Potapczuk, A. Feo, C. Golia, A. D. Shah, Experimental and Computational Simulation of in-flight Icing Phenomena, Progress in Aerospace Sciences 34 (1998) 257-345, the contents of which are herein incorporated by reference.
|
The accretion of ice on an aerodynamic surface is predicted by identifying predetermined atmospheric parameters relevant to ice formation in a particular fluid environment. Then the behaviour of individual fluid elements is simulated based on the identified parameters to create a model of the ice accretion.
| 1
|
BACKGROUND OF INVENTION
This invention relates to chemical compounds having pharmacological activity, to pharmaceutical compositions which include these compounds, and to a pharmaceutical method of treatment. More particularly, this invention concerns certain biurets and aminocarbonyl carbamates which inhibit the enzyme acyl coenzyme A:cholesterol acyltransferase (ACAT), pharmaceutical compositions containing these compounds, and a method of treating hypercholesterolemia and atherosclerosis.
In recent years the role which elevated blood plasma levels of cholesterol plays in pathological conditions in man has received much attention. Deposits of cholesterol in the vascular system have been indicated as causative of a variety of pathological conditions including coronary heart disease.
Initially, studies of this problem were directed toward finding therapeutic agents which would be effective in lowering total serum cholesterol levels. It is now known that cholesterol is transported in the blood in the form of complex particles consisting of a core of cholesteryl esters plus triglycerides and an exterior consisting primarily of phospholipids and a variety of types of protein which are recognized by specific receptors. For example, cholesterol is carried to the sites of deposit in blood vessels in the form of low density lipoprotein cholesterol (LDL cholesterol) and away from such sites of deposit by high density lipoprotein cholesterol (HDL cholesterol).
Following these discoveries, the search for therapeutic agents which are more selective in their action: that is, agents which are effective in elevating the blood serum levels of HDL cholesterol and/or lowering the levels of LDL cholesterol. While such agents are effective in moderating the levels of serum cholesterol, they have little or no effect on controlling the initial absorption of dietary cholesterol in the body through the intestinal wall.
In intestinal mucosal cells, dietary cholesterol is absorbed as free cholesterol which must be esterified by the action of the enzyme acylCoA:cholesterol acyltransferase (ACAT) before it can be packaged into the chylomicrons which are then released into the blood stream. Thus, therapeutic agents which effectively inhibit the action of ACAT prevent the intestinal absorption of dietary cholesterol into the blood stream or the reabsorption of cholesterol which has been previously released into the intestine through the body's own regulatory action.
SUMMARY OF THE INVENTION
The present invention provides compounds of the following general Formula I, methods of using said compounds and pharmaceutical compositions comprising said compounds: ##STR2## wherein R is hydrogen, a straight or branched alkyl C 1 -C 20 or --CH 2 Ph wherein Ph is phenyl and is unsubstituted or is substituted with from 1 to 3 substituents selected from straight or branched alkyl having from 1 to 6 carbon atoms, straight or branched, alkoxy having from 1 to 6 carbon atoms, chlorine, bromine, fluorine, or iodine; wherein each of R 1 and R 2 is selected from:
(a) hydrogen
(b) the group ##STR3## wherein t is zero to 4; w is zero to 4 with the proviso that the sum of t and w is not greater than 5; R 6 and R 7 are independently selected from hydrogen or alkyl having from 1 to 6 carbon atoms, or when R 6 is hydrogen, R 7 can be selected from the groups defined for R 8 ; and R 8 is phenyl or phenyl substituted with from 1 to 3 substituents selected from straight or branched alkyl having from 1 to 6 carbon atoms, straight or branched alkoxy having from 1 to 6 carbon atoms, phenoxy, hydroxy, fluorine, chlorine, bromine, nitro, trifluoromethyl, --COOH, COOalkyl wherein alkyl has from 1 to 4 carbon atoms, or --(CH 2 ) q --NR 9 R 10 wherein R 9 and R 10 are independently hydrogen or alkyl of from 1 to 4 carbon atoms, and q is zero or one;
(c) a straight or branched hydrocarbon chain having from 1 to 20 carbon atoms and which is saturated or contains from 1 to 3 double bonds;
(d) an alkyl group having from I to 6 carbon atoms wherein the terminal carbon is substituted with hydroxy, --NR 9 R 10 wherein R 9 and R 10 have the meanings defined above, or --COOalkyl wherein alkyl is straight or branched and has from 1 to 4 carbon atoms;
(e) phenyl or phenyl substituted with from 1 to 3 substituents selected from straight or branched alkyl having from 1 to 6 carbon atoms, alkoxy which is straight or branched and has from 1 to 6 carbon atoms, alkylthio which is straight or branched and has from 1 to 6 carbon atoms, --(CH 2 ) q --NR 9 R 10 wherein R 9 and R 10 and q have the meanings defined above, hydroxy, nitro, cyano, chlorine, fluorine, bromine, or trifluoromethyl; or
(f) NR 1 R 2 taken together form a monocyclic heterocyclic group selected from pyrrolidino, piperidino, morpholino, or piperazino, each of which is unsubstituted or is substituted with one substituent selected from straight or branched alkyl having from 1 to 6 carbon atoms, phenyl, benzyl, or substituted phenyl or substituted benzyl wherein the substituents vary from 1 to 3 and can be on any position of 2 through 6 of the aromatic ring and are selected from straight or branched alkyl having from 1 to 4 carbon atoms, straight or branched alkoxy having from 1 to 4 carbon atoms, hydroxy, fluorine, chlorine, bromine, trifluoromethyl, cyano, or nitro, or NR 1 R 2 taken together form a phenothiazine or a dibenzoazepine ring system; wherein Q is --NR 3 R 4 , --OR 5 , or --SR 5 wherein each of R 3 and R 4 has the meaning defined above for R 1 and R 2 , and wherein R 5 is selected from:
(a) phenyl which is unsubstituted or is substituted with from one to three substituents selected from:
phenyl,
alkyl having from one to six carbon atoms and which is straight or branched,
alkoxy having from one to six carbon atoms and which is straight or branched,
phenoxy,
hydroxy,
fluorine,
chlorine,
bromine,
cyano,
nitro,
trifluoromethyl,
--COOH,
--COOalkyl wherein alkyl has from one to four carbon atoms and which is straight or branched,
--(CH 2 ) q NR 9 R 10 wherein q, R 9 and R 10 have the meanings defined above;
(b) 1- or 2 naphthyl which is unsubstituted or substituted with one to three substituents selected from
phenyl,
alkyl having from one to six carbon atoms and which is straight or branched, alkoxy having from one to six carbon atoms and which is straight or branched,
hydroxy,
phenoxy,
fluorine,
chlorine,
bromine,
cyano,
nitro,
trifluoromethyl
--COOH,
--COOalkyl wherein alkyl has from one to four carbon atoms and is straight or branched,
--(CH 2 ) q NR 9 R 10 wherein q, R 9 , and R 10 have the meanings defined above;
(c) the group ##STR4## wherein t, w, R 6 , R 7 and R 8 have the meanings defined above; and (d) a straight or branched hydrocarbon chain having from 1 to 20 carbon atoms and which is saturated or contains from one to three double bonds; or a pharmaceutically acceptable salt thereof with the provisos (i) that at least one of R 1 and R 2 and one of R 3 and R 4 is other than hydrogen; (ii) that when both of R 1 and R 2 or when both of R 3 and R 4 are the group ##STR5##
R 7 is hydrogen or alkyl.
DETAILED DESCRIPTION OF INVENTION
The compounds of Formula I provide a class of biurets and aminocarbonyl carbamates which are ACAT inhibitors rendering them useful in treating hypercholesterolemia and atherosclerosis. The biurets of this invention may be depicted by the following general Formula II, the aminocarbonyl carbamates may be depicted by the following general Formula III, and the aminocarbonyl thiocarbamates may be depicted by the following general Formula IV: ##STR6##
In the above general Formulas II, III, and IV the various substituents R, R 1 , R 2 , R 3 , R 4 and R 5 have the meanings defined in Formula I.
In the compounds of the present invention illustrative examples of straight or branched saturated hydrocarbon chains or alkyl having from 1 to 20 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, n-heptyl, n-octyl, n-undecyl, n-dodecyl, n-hexadecyl, 2,2-dimethyldodecyl, 2-tetradecyl, and n-octadecyl groups.
Illustrative examples of straight or branched hydrocarbon chains having from 1 to 20 carbon atoms and having from 1 to 3 double bonds include ethenyl, 2-propenyl, 2-butenyl, 3-pentenyl, 2-octenyl, 5-nonenyl, 4-undecenyl, 50heptadecenyl, 3-octadecenyl, 9-octadecenyl, 2,2-dimethyl-11-eicosenyl, 9,12-octadecadienyl, and hexadecenyl.
Straight or branched alkoxy groups having from 1 to 6 carbon atoms include, for example, methoxy, ethoxy, n-propoxy, tert-butyl, and pentyloxy.
The term alkylthio having from 1 to 6 carbon atoms means the group C 1-6 alkyl-S-- wherein the alkyl moiety is straight or branched.
Preferred compounds of this invention are those of Formula II and III wherein one of R 1 and R 2 is hydrogen and more preferred are compounds wherein the other of R 1 and R 2 is substituted phenyl. More preferably in the compounds of Formula II one of R 1 and R 2 is 2,6-disubstituted phenyl and the other of R 1 and R 2 is hydrogen. Also, more preferred in the compounds of Formula III are those wherein one of R 1 and R 2 is hydrogen, the other is 2,6-disubstituted phenyl and R 5 is a straight or branched saturated hydrocarbon chain having from 1 to 20 carbon atoms.
Pharmaceutically acceptable salts of the compounds of Formula I, II, III, and IV are also included as a part of the present invention.
The base salts may be generated from compounds of Formulas I, II, and III by reaction of the latter with one equivalent of a suitable nontoxic, pharmaceutically acceptable base followed by evaporation of the solvent employed for the reaction and recrystallization of the salt, if required. The compounds of Formula I may be recovered from the base salt by reaction of the salt with an aqueous solution of a suitable acid such as hydrobromic, hydrochloric, or acetic acid.
Suitable bases for forming base salts of the compounds of this invention include amines such as triethylamine or dibutylamine, or alkali metal bases and alkaline earth metal bases. Preferred alkali metal hydroxides and alkaline earth metal hydroxides as salt formers are the hydroxides of lithium, sodium, potassium, magnesium, or calcium. The class of bases suitable for the formation of nontoxic, pharmaceutically acceptable salts is well known to practitioners of the pharmaceutical formulation arts. See, for example, Stephen N. Berge, et al, J Pharm Sciences 66:1-19 (1977).
Suitable acids for forming acid salts of the compounds of Formulas I, II, and III which contain a basic group include, but are not necessarily limited to acetic, benzoic, benzenesulfonic, tartaric, hydrobromic, hydrochloric, citric, fumaric, gluconic, glucuronic, glutamic, lactic, malic, maleic, methanesulfonic, pamoic, salicylic, stearic, succinic, sulfuric, and tartaric acids. The acid addition salts are formed by procedures well known in the art.
Certain compounds of the present invention may also exist in different stereoisomeric forms by virtue of the presence of asymmetric centers in the compound. The present invention contemplates all stereoisomeric forms of the compounds as well as mixtures thereof, including racemic mixtures. Individual stereoisomers may be obtained, if desired, by methods known in the art as, for example, the separation of stereoisomers in chiral chromatographic columns.
Further, the compounds of this invention may exist in unsolvated as well as solvated forms with pharmaceutically acceptable solvents such as water, ethanol, and the like. In general, the solvated forms are considered equivalent to the unsolvated forms for the purposes of this invention.
As shown by the data presented below in Table 1, the compounds of the present invention are potent inhibitors of the enzyme acyl-CoA: cholesterol acyltransferase (ACAT), and are thus effective in inhibiting the esterification and transport of cholesterol across the intestinal cell wall. The compounds of the present invention are thus useful in pharmaceutical formulations for the treatment of hypercholesterolemia or atherosclerosis.
The ability of representative compounds of the present invention to inhibit ACAT was measured using an in vitro test more fully described in F. J. Field and R. G. Salone, Biochemica et Biophysica 712:557-570 (1982). The test assesses the ability of a test compound to inhibit the acylation of cholesterol by oleic acid by measuring the amount of radiolabeled cholesterol oleate formed from radiolabeled oleic acid in a tissue preparation containing rabbit intestinal microsomes.
The data appear in Table 1 where they are expressed as IC 50 values; i.e., the concentration of test compound required to inhibit the activity of the enzyme by 50%.
TABLE 1______________________________________Example IAI IC.sub.50 (μM)______________________________________ 1 0.6 2 >1 3 >5 4 1.04 5 0.34 6 0.35 7 0.25 8 0.89 9 >510 >511 0.7512 1.913 3.514 1.715 0.9816 7.817 0.06518 0.1219 0.3520 0.3921 1.0622 0.7523 6.824 0.04625 >126 0.17______________________________________
In one in vivo screen designated APCC, male Sprague-Dawley rats (200 to 225 g) were randomly divided into treatment groups and dosed at 4 PM with either vehicle (CMC/Tween) or suspensions of compounds in vehicle. The norma chow diet was then replaced with a high fat, high cholesterol diet with 0.5% cholic acid. The rats consumed this diet ad libitum during the night and were sacrificed at 8 AM to obtain blood samples for cholesterol analysis using standard procedures. Statistical differences between mean cholesterol values for the same vehicle were determined using analysis of variance followed by Fisher's least significant test. Compounds were dosed at 30 mg/kg unless otherwise noted. The results of this trial for representative compounds of the present invention appear in Table 2.
TABLE 2______________________________________ % Change in Plasma TCCompound of Example Values (mg/dL)______________________________________ 1 -9 4 -13* 5 -40* 6 -5* 7 -23* 8 -18*11 -27*12 -19*14 -815 -917 -1418 -3819 -2620 -2421 -2222 -2223 -2624 -3325 No change______________________________________ *Dosed at 50 mg/kg
In therapeutic use as agents for treating hypercholesterolemia or atherosclerosis, the compounds of Formula I or pharmaceutically acceptable salts thereof are administered to the patient at dosage levels of from 250 to 3000 mg per day. For a normal human adult of approximately 70 kg of body weight, this translates into a dosage of from 5 to 40 mg/kg of body weight per day. The specific dosages employed, however, may be varied depending upon the requirements of the patient, the severity of the condition being treated, and the activity of the compound being employed. The determination of optimum dosages for a particular situation is within the skill of the art.
For preparing the pharmaceutical compositions from the compounds of this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, and cachets. Pharmaceutical compositions of the compounds of general Formula I are prepared by procedures well known in the art.
A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders, or tablet disintegrating agents; it can also be an encapsulating material.
In powders, the carrier is a finely divided solid which is in a mixture with the finely divided active component. In tablets, the active component is mixed with the carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired.
Powders and tablets preferably contain between about 5% to about 70% by weight of the active ingredient. Suitable carriers are magnesium dicarbonate, magnesium stearate, talc, lactose, sugar, pectin, dextrin, starch, tragacanth, methyl cellulose, sodium carboxymethyl cellulose, a low-melting wax, cocoa butter, and the like.
The term "preparation" is intended to include the formulation of the active compound with encapsulating material as a carrier providing a capsule in which the active component (with or without other carriers) is surrounded by a carrier, which is thus in association with it. In a similar manner cachets are also included.
Tablets, powders, cachets, and capsules can be used as solid dosage forms suitable for oral administration.
Liquid form preparations include solutions, suspensions, or emulsions suitable for oral administration. Aqueous solutions for oral administration can be prepared by dissolving the active compound in water and adding suitable flavorants, coloring agents, stabilizers, and thickening agents as desired. Aqueous suspensions for oral use can be made by dispersing the finely divided active component in water together with a viscous material such as natural or synthetic gums, resins, methyl cellulose, sodium carboxymethylcellulose, and other suspending agents known to the pharmaceutical formulation art.
Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is divided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation containing discrete quantities of the preparation, for example, packeted tablets, capsules, and powders in vials or ampoules. The unit dosage form can also be a capsule, cachet, or tablet itself, or it can be the appropriate number of these packaged forms.
The compounds of this invention are prepared by various means. The compounds of Formula II wherein R is hydrogen can be prepared according to the following reaction scheme wherein R 1 , R 2 , R 3 and R 4 have the meanings defined in Formula. ##STR7## A solution of an amine (a) in an appropriate solvent, such as, diethyl ether, dichloromethane or tetrahydrofuran is added dropwise to a solution of chlorocarbonyl isocyanate in a similar solvent, at 0° or less (-78° to 0° C.). The resulting solution is stirred for 1 to 6 hours. A solution of a second amine (R 3 R 4 NH) and an acid scavenger such as triethylamine or pyridine in an appropriate solvent is added dropwise. The resulting mixture is warmed to room temperature and let stand for 2 to 24 hours. The reaction is partitioned between an appropriate organic solvent and an aqueous acid wash (1N HCl, 5% citric acid, etc). The organics are dried with an appropriate drying agent such as MgSO 4 or Na 2 SO 4 and concentrated to give crude product. Chromatography gives the desired product. The compounds of Formula II wherein R is an alkyl group of from 1 to 20 carbon atoms or --CH 2 Ph are prepared from the compound of formula (c) by treatment with DBU (1,8-diazabicyclo[5,4,0]undec-7-ene) and an alkyliodide or an appropriate benzyl iodide by procedures well known in the art.
The compounds of Formula II may also be prepared according to the following reaction scheme wherein ##STR8## phosgene (e) in an appropriate solvent, such as, toluene, or benzene is added to a solution of the urea (d) in a solvent such as diethyl ether, tetrahydrofuran or dichloromethane. Upon completion of the reaction and removal of the excess phosgene the residue containing (f) is redissolved in, e.g., tetrahydrofuran and the amine NHR 3 R 4 is added. The reaction mixture is stirred at room temperature for from 6 to 24 hours to give the product (g). The urea (d) is prepared by reaction of an isocyanate of the formula R 1 R 2 NCO and an amine NH 2 R by means well known in the art.
The compounds of Formula III and IV wherein R is hydrogen may be prepared as depicted below wherein X is oxygen or sulfur: ##STR9##
A solution of the first nucleophile (R 5 XH or R 1 R 2 NH) in an appropriate solvent such as diethyl ether, dichloromethane or tetrahydrofuran is added dropwise to a cold (<0° C.) solution of chlorocarbonyl isocyanate in a similar solvent. The resulting solution is aged (1/2 to 6 hours) before a solution of the second nucleophile (R 1 R 2 NH or R 5 XH) and an acid scavenger such as triethylamine or pyridone in an appropriate solvent such as diethyl ether, dichloromethane or tetrahydrofuran is added dropwise. The resulting mixture is warmed to room temperature and aged (1/2 to 16 hours). The reaction is then partitioned between an organic solvent and an acidic aqueous solution (e.g., 1N HCl, 5% citric acid). The organic layer is dried and concentrated to give a crude product mixture. Chromatography then gives the desired product.
The compounds of Formula III and IV wherein R is alkyl of from 1 to 20 carbon atoms or --CH 2 Ph are prepared from the compounds of formula (i) by treatment with DBU and an alkyliodide or an appropriate benzyliodide by well known procedures.
The various alcohols, amines and ureas depicted above in the reaction schemes are commercially available or can be prepared by means well known in the art.
The following specific examples further illustrate the invention.
EXAMPLE 1
N'-[2,6-bis(1-methylethyl)phenyl]-2-methyl-N,N-diphenyliminodicarbonic diamide
Phosgene (in toluene, 10 mmol, 7.92 mL) was added to a solution of N-methyl-N',N'-diphenylurea (10 mmol, 2.26 g) in 20 mL THF at room temperature. The mixture was stirred at room temperature for 2 days and then 60° C. for 2 weeks. The solvent and excess phosgene were removed under vacuum. The residue was redissolved in 20 mL of THF and 2,6-diisopropylaniline (20 mmol, 3.55 g) was added all at once. A white precipitate appeared, and the mixture was stirred at room temperature overnight. The solvent was removed and 50 mL of EtOAC was added to the residue. The mixture was filtered and the filtrate was concentrated under vacuum. The product was isolated by chromatography (hexane: EtOAc=8:1). The oil weighed 2.6 g (65%). IHNMRdata for Example 1.
δ 1.1˜1.4 (M,12H); 2.87 (S. 3H)
3.09˜3.29 (M,2H); 3.45 (S. 1H)
6.9˜7.5 (M,13H)
EXAMPLE 2
N-[2,6-bis(1-methylethyl)phenyl)-N'-(diphenylmethyl) iminodicarbonic amide
A solution of 2,6-diisopropylaniline (1.5 g, 8.5 mmol) in 50 mL Et 2 O was added dropwise to a solution of chlorocarbonyl isocyanate (0.68 mL, 8.5 mmol) in 40 mL Et 2 O at -50° C. under an atmosphere of N 2 . The resulting solution was stirred for 3 hours, allowing the temperature to rise to -30° C. A solution of benzhydrylamine (1.46 mL, 8.5 mmol) and excess triethylamine (1.0 mL) in 50 mL Et 2 O was added dropwise. The resulting suspension was warmed to room temperature and stirred for 16 hours. The reaction was partitioned between EtOAc and 1N HCl. The organic layer was dried over MgSO 4 , filtered, and evaporated to give a white foam. Chromatography (SiO 2 , 10% EtOAc/hexanes) gave 0.86 g (23%) of the title compound as a white solid, M.P. 139° to 141° C.
When in the procedure of Example 2 an appropriate amount of the amine listed below was substituted for benzhydrylamine and the general procedure of Example 2 was followed the respective products listed below were obtained.
______________________________________Example Amine Product______________________________________3 2,6-bis(1- N,N'-bis[2,6-bis(1-methyl- methylethyl) ethyl)phenyl]imidodicarbonic phenylamine diamide, m.p. 222-224° C.4 dibenzylamine N'-[2,6-bis(1-methylethyl)- phenyl]-N,N-bis(phenyl- methyl)imidodicarbonic diamide, m.p. 163-166° C.5 diphenylamine N'-[2,6-bis(1-methylethyl)- phenyl]-N,N-diphenylimido- dicarbonic diamide, m.p. 135-139° C.6 dioctylamine N-[2,6-bis(1-methylethyl) phenyl]-N,N-dioctylimido- dicarbonic diamide, m.p. 44-48° C.7 dibutylamine N'-[2,6-bis(1-methylethyl) phenyl]-N,N-dibutylimido- dicarbonic diamide, m.p. 112-114°C.8 5H-dibenz- N-[[[2,6-bis(1-methylethyl) [b,f]azepine phenyl]amino]carbonyl]- 10,11-dihydro-5H-dibenz [b,f]azepin-5-carboxamide, m.p. 178-179° C.9 pyrrolidine N-[[[2,6-bis(1-methylethyl) phenyl]amino]carbonyl]-1- pyrrolidinecarboxamide, m.p. 175-177° C.10 diethylamine N'-[2,6-bis(1-methylethyl) phenyl]-N,N-diethylimido- dicarbonic diamide; m.p. 160-163° C.11 (1-methyl- N'-[2,6-bis(1-methylethyl) ethyl) phenyl]-N-(1-methylethyl)- (benzyl)amine N-(phenylmethyl) imidodicarbonic diamide, m.p. 92-95° C.12 phenothiazine N-[[[2,6-bis(1-methylethyl) phenyl]amino]carbonyl]-10H- phenothiazine-10-carboxa- mide, m.p. 176-177° C.13 4-phenyl- N-[[[2,6-bis(1-methylethyl) piperidine phenyl]amino]carbonyl]-1- [(4-phenyl)piperidine] carboxamide, m.p. 205-207°C.14 (methyl) N'-[2,6-bis(1-methylethyl) (tetradecyl) phenyl]-N-methyl-N-tetra- amine decylimidodicarbonic diamide, m.p. 47-49° C.______________________________________
EXAMPLE 15
[[[2,6-bis(1-methylethyl)phenyl]amino]carbonyl] carbamic acid,2,6-bis(1-methylethyl)phenyl ester
A solution of 2,6-diisopropylphenol (1.69 g, 9.5 mmol) in 50 mL Et 2 O was added dropwise to a solution of chlorocarbonyl isocyanate (0.76 mL, 9.5 mmol) in 50 mL Et 2 O at -50° C. under an atmosphere of N 2 . The temperature was raised to 0° C. over 2 hours. A solution of 2,6-diisopropylaniline (1.68 g, 9.5 mmol) and excess triethylamine (1 mL) in 50 mL Et 2 O was added dropwise to the reaction. The resulting mixture was stirred at room temperature for 16 hours. Partitioned between 1N HCl and EtOAc. The organic layer was dried (MgSO 4 ), filtered, and concentrated to give a white solid. Chromatography (10% EtOAc/hexanes) gave the title compound (1.50 g, 37%), M.P. 184°-186° C.
When in the procedure of Example 15 an appropriate amount of the alcohol listed below was substituted for 2,6-diisopropylphenol and the general procedure of Example 15 was followed the respective products listed below were obtained.
______________________________________Example Alcohol Product______________________________________16 benzhydrol [[[2,6-bis(1-methylethyl) phenyl]amino]carbonyl] carbamic acid, diphenyl- methyl ester, m.p. 169-172° C.17 1,1-dimethyl- [[[2,6-bis(1-methylethyl) tridecanol phenyl]amino]carbonyl]carbam- ic acid, 1,1-dimethyl- tridecyl ester, m.p. 65-67° C.18 dodecanol [[[2,6-bis(1-methylethyl) phenyl]amino]carbonyl] carbamic acid, dodecyl ester, m.p. 100-102° C.19 1-methyl- (±)[[[2,6-bis(1-methylethyl) undecanol phenyl]amino]carbonyl] carbamic acid, 1-methylun- decyl ester, m.p. 59-61° C.20 1-methyl- (±)[[[2,6-bis(1-methylethyl) octanol phenyl]amino]carbonyl] carbamic acid, 1-methyloctyl ester, m.p. 100-102° C.21 1-methyl- (±)[[[2,6-bis(1-methylethyl) hexanol phenyl]amino]carbonyl] carbamic acid, 1-methylhexyl ester, m.p. 113-115° C.22 1-methyl- (±)[[[2,6-bis(1-methylethyl) nonanol phenyl]amino]carbonyl] carbamic acid, 1-methylnonyl ester, m.p. 84-86° C.23 1-methyl- (±)[[[ 2,6-bis(1-methylethyl) pentadecanol phenyl]amino]carbonyl] carbamic acid, 1- methylpentadecyl ester, m.p. 68-70° C.24 1-methyl- (±)[[[2,6-bis(1-methylethyl) tridecanol phenyl]amino]carbonyl] carbamic acid, 1- methyltridecyl ester, m.p. 65-66° C.______________________________________
When in the procedure of Example 15 an appropriate amount of the amine listed below was substituted for 2,6-diisopropylaniline and the general procedure of Example 15 was followed the respective products listed below were obtained.
______________________________________Example Amine Product______________________________________25 benzhydryl- [[(diphenylmethyl)amino] amine carbonyl]carbamic acid, 2,6- bis(1-methylethyl)phenyl ester, m.p. 174-176° C.26 diphenylamine [(diphenylamino)carbonyl] carbamic acid, 2,6-bis(1- methylethyl)phenyl ester, m.p. 142-146° C.______________________________________
When in the procedure of Example 15 an appropriate amount of dodecanethiol or 1-methyltridecanethiol is substituted for 2,6-diisopropylphenol the following compounds are obtained:
[[[2,6-bis(1-methylethyl)phenyl]amino]carbonyl] thiocarbamic acid, dodecyl ester;
[[[2,6-bis(1-methylethyl)phenyl]amino]caronyl] thiocarbamic acid, 1-methyltridecyl ester.
|
Novel compounds useful as ACAT inhibitors having the formula ##STR1## wherein Q is R 5 O; R 5 S-- or NR 3 R 4 ; wherein R is hydrogen or alkyl C 1 -C 20 or --CH 2 Ph; wherein R 1 , R 2 , R 3 and R 4 are hydrogen, a hydrocarbon chain aralkyl, phenyl or substituted phenyl or form a heterocyclic ring; wherein R 5 is phenyl or substituted phenyl, naphthyl or substituted naphthyl, a hydrocarbon chain or aralkyl.
| 2
|
CROSS REFENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of the following co-pending U.S. provisional applications, each of which is incorporated herein by reference: Ser. No. 60/241,693, entitled “Bulkhead And Partition System,” filed Oct. 19, 2000; Ser. No. 60/269,436, entitled “Bulkhead And Partition System And Methods And Apparatus For Molding Plastic Parts,” filed Feb. 16, 2001; and Ser. No. 60/296,623, entitled “Bulkhead And Partition System And Methods And Apparatus For Molding Plastic Parts,” filed Jun. 7, 2001.
TECHNICAL FIELD
[0002] The present invention relates to panels that can be used to separate or insulate cargo during transportation or storage, including partitions and bulkheads.
BACKGROUND
[0003] Perishable items such as produce and meat are often transported in refrigerated trailers, railcars, or ocean-going containers that can be transported on ships, trains or trucks. Such cargo transport devices are typically equipped with a refrigeration unit that conditions the air inside the cargo space, thereby maintaining desired temperatures and humidities during transportation or storage. Refrigerated trailers, railcars and containers are typically configured so as to enclose a single, large cargo space. Their refrigeration units will accordingly maintain the entire cargo space at the same temperature and humidity unless the cargo area is somehow divided. However, when the perishable cargo does not fill the entire trailer, cooling the entire cargo area is unnecessary and costly. It causes unnecessary strain and wear on the refrigeration unit, increases fuel consumption, raises transportation costs, and lengthens the time necessary to cool the perishable cargo after any temperature aberration.
[0004] Movable panels having a specialized construction permit the cargo space of trailers, rail cars, and containers to be readily divided into sections of varying sizes. Such panels are commonly referred to as “partitions” or “bulkheads,” depending on the manner in which they are installed in a cargo space. The structure and configuration of partition and bulkhead systems also vary depending on whether they are being deployed in a trailer, railcar, or container.
[0005] Partitions currently used in refrigerated truck trailers typically extend from floor to ceiling and are generally comprised of modular sections akin to cubicle walls commonly used in office spaces. The modular sections are often mounted in channels or grooves on the trailer floor, held in place by friction, hinged to the trailer ceiling, or otherwise mechanically fastened in place so as to compartmentalize trailers and truck bodies for multi-temperature food distribution. The panels are used to divide the trailer or body both longitudinally, along the long axis of the trailer, and laterally, across the width of the trailer. Some partition systems include panels which can be readily removed and placed along the sidewall of the trailer when not in use.
[0006] Bulkheads typically have a similar construction but extend across the width of a trailer to form separate fore and aft cargo areas. Like partitions, insulated bulkheads allow a refrigerated hauler to carry two or more loads at different temperatures within the same trailer or cargo container. For instance, bulkheads may be used to separate fresh food products from frozen or dry goods. Bulkheads can be formed of one integral unit or a plurality of sections that are hinged, attached, or interlocking. The individual sections are typically movable by virtue of being releasably mounted on channels, tracks, hinges or the like. When installed in a desired configuration, the sections are often frictionally fit, hinged or otherwise fastened to trailer wall, floor or ceiling. Bulkheads are optionally equipped with walk-through doors similar to those used in partitions to permit ingress to and egress from each conditioned cargo area.
SUMMARY
[0007] The present invention is directed to improved panels and bulkhead and partition systems. In one embodiment of the invention, the panels are seamless, one-piece members integrally formed from a single resinous material such as a thermoplastic polymer. In certain embodiments, the panels include depressions that obviate the need to fill the panels with foam or other supportive filler material. In still other embodiments, the panels have no fasteners extending through panel so the panels are substantially impervious to moisture. Other embodiments have grooves or similar mounting means disposed around their peripheral edges to which edge members such as supports or flexible seals may be mounted. In yet other embodiments, the grooves are arranged so as to permit worn out seals to be quickly and easily replaced without the need to remove mechanical fasteners. In a further embodiment, the panels include integrally formed handle structures. In another embodiment, the panels have additional depressions or ribs which promote air flow past adjacent cargo and provide additional rigidity and strength.
[0008] The details of these and other embodiments of the invention are set forth in the description below. Other features, objects, and advantages of the invention will be apparent from the description, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a perspective view of an assembled partition with seal strips and nylon handles;
[0010] FIG. 1A is a cross sectional view of the panel taken along a horizontal line;
[0011] FIG. 1B is a cross sectional view of an edge of the panel and the seal mounted thereto;
[0012] FIG. 1C is a partial perspective view of the upper-left edge of the core panel of FIG. 1 , shown with the seals cut away at the corner;
[0013] FIG. 2 is a plan view of the bottom half of a two-piece adjustable mold with which the panel of FIG. 1 may be manufactured;
[0014] FIG. 2A is a cross sectional view of the bottom half of the two-piece mold;
[0015] FIG. 2B is a partial perspective view of the mold of FIG. 2 ;
[0016] FIG. 3 is a plan view of the complementary top half of the mold of FIG. 2 ;
[0017] FIG. 3A is a cross sectional view of the top half of the two-piece mold;
[0018] FIG. 3B is a plan view of the mold of FIG. 3 after the adjustable rails have been removed;
[0019] FIG. 4 is a cross sectional view of the bottom and top halves of the closed two-piece mold;
[0020] FIG. 5 is a partial perspective view of the end of the rail member shown in FIG. 2B .
[0021] FIG. 6 is a plan view of the complementary top half of an alternate mold;
[0022] FIG. 6A is a cross sectional view of the rail members shown in FIG. 6 ;
[0023] FIG. 6B is a metal edge member mounted in the rail members shown in FIG. 6A ; and
[0024] FIGS. 7 through 7 C are a cross sectional views of rail members for use in the molds of FIGS. 2-6 .
[0025] FIG. 8 is a partial perspective view of the upper-left edge of the panel of FIG. 1 , shown without the seal members;
[0026] FIG. 9 is a partial perspective view of the upper-left edge of the panel of FIG. 1 , shown with the seals;
[0027] FIG. 10 is a partial perspective view of the upper-left edge of the panel of FIG. 1 , fitted with foam-type seals;
[0028] FIG. 11 is a cross sectional views of a metal edge member that can be integrally molded into the periphery of the panel;
[0029] FIG. 12 is a cross sectional views of another metal edge member that can be integrally molded into the periphery of the panel; and
[0030] FIG. 13 is a cross sectional view of an adjustable seal that can be mounted to bulkhead and partition panels of varying widths.
[0031] Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] FIG. 1 shows one embodiment of a complete, assembled partition panel 1 constructed in accordance with the present invention. The panel includes a front face 10 and opposed rear face 11 which are held in generally parallel relation and define a cavity 12 therebetween (shown in FIG. 2 .). Each of the front face 10 and rear face 11 have depressions or “stand-offs” 13 formed therein which extend across substantially the entire cavity. The faces 10 , 11 also may have integral longitudinal ribbing 14 which adds rigidity and permits cool air to flow between the faces 10 , 11 and adjacently disposed cargo. Handle formations 15 are integrally molded into the faces 10 , 11 . The handle formations 15 include arcuate channels 16 that extend from the front face 10 to the rear face 11 and accommodate handles such as nylon straps 17 . The panel of FIG. 1 may be fitted with edge members 18 that include wipe-type seals 25 similar to triple-blade windshield wipers.
[0033] In use, the panel can be mounted in a refrigerated trailer such that its faces 10 , 11 extend laterally across the width of the trailer in the manner depicted in the publication Insulated Bulkheads by FG Products, Inc. of Rice Lake, Wis., which is contained in the cross-referenced applications. The panel may be fitted with appropriate edge members so that the bulkhead can be effectively held in place by tracks in the trailer floors, walls, or ceiling. Alternatively, the panel may be hinged to overhead track systems or mounted in other manners known in the art.
[0034] As shown in the publication Center Partition Systems—Designed for Positive Temperature Control, also by FG Products, Inc. of Rice Lake, Wis., (also contained in the cross-referenced applications), the panel of FIG. 1 can be readily adapted for use in a partition system. Suitable mounting and sealing means are used in place of edge members 18 and, if desired, mounting formations adapted to receive additional nylon straps may be molded into the faces 10 , 11 . A door or portal may also be incorporated into the structure of FIG. 1 to permit rapid ingress and egress from the enclosed cargo area. Those of skill in the art will readily appreciate that other modifications can be made to the bulkhead of FIG. 1 to further adapt it for use as a partition, including but not limited to incorporation of those features described in the publication Center Partition Systems.
[0035] The core of the bulkhead is shown in more detail in FIGS. 1A and 1B . As shown in FIG. 1A , the depressions 13 can extend substantially across the entire width of the cavity 12 so as to maintain the faces 10 , 11 in spaced apart relation. The faces 10 , 11 are preferably constructed of a lightweight, tough, ductile resinous material such as polyethylene, but those of skill in the art will appreciate that a wide variety of other suitable materials may be used, including but not limited to other poly-α-olefins, composite materials, wood, and metal. The wall thickness is preferably with the range 0.05 inch to 0.5 inch and even more preferably within the range 0.15 inch to 0.35 inches. The left and right distal edges of the faces 10 , 11 include tapered or beveled regions 19 and channels 20 adapted to hold edge members 18 . The channels 20 and tapered regions 19 may optionally extend around the entire periphery of the panel as shown in FIG. 1 .
[0036] FIG. 1C shows how edge members 18 can be attached to the bulkhead. Mounting member 24 slideably engages the receiving channels 20 . Flexible blade- or wipe-type seals 25 extend peripherally from the mounting member 18 so as to contact the adjacent surface, which can be another bulkhead or partition or a trailer wall, floor, or ceiling. FIG. 1B is a cross sectional view showing how mounting member 24 engages the receiving channels and thereby rigidly attaches seal 18 to the panel.
[0037] The aforementioned bulkheads and partitions may be manufactured in customized dimensions and configurations with an adjustable mold such as that depicted in FIGS. 2-6 . FIG. 2 is a plan view of a first adjustable mold 28 for use in apparatus for thermoforming, such as vacuum forming, and rotational molding. Fixed rails 29 are disposed along the bottom and left edge of the mold area 31 . Adjustable rails 30 are disposed at the right and upper regions of the mold area 31 . As more clearly shown in FIG. 2B , stand-off forms 32 and handle forms 33 project vertically from the mold 28 . Returning to FIG. 2 , the adjustable rails 30 are mounted on tracks 34 which may be disposed below, inside, or outside the adjustable rails 30 . The adjustable rails 30 are mechanically engaged with the tracks 34 with fasteners, pins, clamps, or other known means so as to permit the rails to be moved toward or away from the center of the mold area 31 . Rail inserts 35 are adapted to engage the adjustable rails 30 and fixed rails 29 in flush relation, as with pins, bolts, clamps or other known means.
[0038] In an alternate embodiment, the fixed rails 29 may extend the entire height and width of the mold area 31 . The right adjustable rail 30 is comprised of a single member that extends from the bottom fixed rail 29 to the top of the mold area 31 . The bottom of the right adjustable rail 30 is “coped” to the bottom fixed rail 29 like a baseboard so as to form a symmetrical seam and corner region. The upper adjustable rail 30 extends between the left fixed rail 29 and the right adjustable rail 30 and is coped thereto. Upper adjustable rails 30 are provided in varying widths. That construction obviates the need for rail inserts 35 . The adjustable rails 30 are manipulated by articulation of a cooperating track and mounting member disposed entirely outside the mold area 31 so that no portion of the track 34 has to be filled to prevent aberrations in the face portions 10 , 11 .
[0039] A wide variety of adjustable rail systems may be employed. Each face 10 , 11 can be vacuum-formed separately using a mold having a similar array of adjustable members, whereafter the formed panels 10 , 11 may be attached to one another according to known methods. Likewise, the adjustable mold members need not be slideably attached to rails or tracks—rather, they may be adjustably fastened directly to the mold 28 , 36 with pins, bolts, clamps or other suitable means. Those skilled in the art will appreciate that myriad other modifications may be readily made to the above described adjustable molding apparatus so as to optimize its performance in a particular application.
[0040] In use, the fabricator manipulates the adjustable rails 30 to the desired dimensions on the first mold 38 and a second, complementary mold 36 shown in FIG. 3 . The molds are then closed together as shown in the cross section views of FIG. 4 . The foregoing operations can occur either before or after the mold is placed into a conventional thermoforming apparatus such as a vacuum forming device or a rotomolder. When rotational molding is employed, it may be advantageous to counterweight the molds 28 , 36 so that the center of gravity of the closed mold assembly is disposed along the axis about which the mold is spun.
[0041] FIG. 5 is a close-up view of portion 100 of the mold shown in FIG. 2B . The fixed rail 29 is bolted to the mold half 28 with a threaded fastener 101 . The cross-sectional contour of the rail member 29 matches the contour of the peripheral portions of the molded panel 1 and the seal mounting members 24 .
[0042] FIG. 6 depicts a alternate mold half 110 . Adjustable rail members 111 are installed in the mold cavity. Trim members 112 span the cavity between rail member 111 and define the mold area in which the resin can be deposited. Ridge elements 113 are disposed longitudinally and latitudinally in the mold cavity so as to cause the formation of ridges or depressions in the final molded panel that accommodate expansion or shrinkage of the panel faces. After rotomolding is complete, trim members 112 form the outer edges of the panel. FIG. 6A is a close-up view of matable rail members 111 a and 111 b which clamp down upon trim members 112 and hold them in place. FIG. 6B is a cross sectional view of the matable rail members 111 a and 111 b after a trim member 112 has been installed therein. After the mold halves are closed together, the upper flange 112 a and lower flange 112 b fit flush against the faces of the mold halves and thereby, in cooperation with the mold half faces, define a mold cavity.
[0043] FIGS. 7 through 7 C show alternate mold edge members 111 adapted to form contours of various shapes in the bulkhead. The mold edges 111 form an edge contour adapted to receive the wipe seals or other edge members discussed above. The depicted members 111 can be used in place of the members 111 shown in FIG. 6A . Optionally, a rigid trim member made of metal or other suitable material can be inserted in the interior of the mold edge members so as cause the rigid trim member to be integrally molded into the bulkhead as the bulkhead's peripheral edge as described above in connection with FIG. 6 . The mold edge members 111 shown in FIGS. 7A to 7 C form arcuate, matable contours into the bulkhead. The bulkhead edge molded by the members 111 of FIG. 7A will mate with a contoured edge formed by the mold element 111 of FIG. 7C .
[0044] The panels discussed above can be comprised of polyethylene and glass fibers made by an improved molding technique. Fibers, filaments or other reinforcing structures made of glass, carbon or other suitable materials may be molded directly into a base polymer, such as polyethylene, polypropylene, nylon, or polycarbonate. The fibers in the resulting parts can extend through the entire thickness of the material, thereby significantly increasing the part's strength, toughness and structural integrity. Advantageously, the dimensions of the fibers can be varied such that fibers extend into an internal cavity of the part to act as an interface with material placed therein, such as foam. The protruding fibers thus can act to integrally connect and secure the polymeric composite to an adjacently situated foam, resin, polymer, composite, or other material. In certain applications, this is particularly advantageous because the fibers can inhibit the adjacent material from delaminating from an outer shell comprised of a polymeric composite. Filler materials, such as foam, can thus act not only as an insulator, but also as an additional source of rigidity and strength.
[0045] The rotational molding process (also called “rotomolding”) is initiated by preparing a mold that is suitable to be placed in a rotomolding machine that can include loading, heating, and cooling areas. Depending on the molding machine, multiple molds can be mounted, heated, and cooled simultaneously. A predetermined amount of plastic resin—often in the form of a powder—can be loaded into each mold. The amount of resin can be selected based on the size of the mold and the desired wall thickness. For greater wall thicknesses, an increased amount of resin can be used. A predetermined amount of reinforcing elements such as glass fibers can also added to each mold. The amount of fibers can be selected based upon the desired properties of the resulting composite. A greater volume or weight fraction of fibers can be added where stiffer, stronger parts are desired. Smaller volume or weight fractions of fibers can be added to increase flexibility or to decrease cost, for example.
[0046] The molds can then be closed and placed into a heating area of the rotomolding apparatus, which can include an oven. The molds can be slowly rotated as they are heated along both vertical and horizontal axes. As the resin touching the mold softens or melts, it adheres to both the adjacently situated fibers and the wall of the mold. The powder adjacent to the softened resin also softens or melts and then adheres to the resin situated against the wall of the mold and the adjacently situated fibers. The continued rotation of the molds can advantageously cause the resin to coat all surfaces of the inside of the mold to a uniform depth or thickness. Advantageously, the mold can be rotated after the mold is moved into a cooling area so that the depth of the resin adhered to the internal walls of the mold remains constant. The temperatures, rotational rotates, and materials can be selected to control the wall thickness and the additional material thickness (and strength) at the corners of a part. Depending on the thermal expansion and contraction characteristics of the materials selected, the speed of the rotation, and the cooling rate, the parts can separate from the mold during the cooling process. The mold can be opened after the cooling cycle is complete, whereafter the molded part is removed.
[0047] The use of reinforcing elements such as fibers advantageously reduces the coefficient of shrinkage and expansion of the resulting part. For instance, a bulkhead or panel molded as described above and filled with polyurethane foam is typically exposed to extreme temperatures. During use in refrigerated transport application or in a refrigerated cooler, the bulkhead is at a very low temperature, such as zero degrees Fahrenheit. At other times, the bulkhead may be exposed to temperatures in excess of one hundred degrees Fahrenheit. The reduced thermal expansion and contraction coefficient of the part tends to further inhibit delamination of the outer composite from the internal foam. As noted above, the protruding fibers also greatly.
[0048] Depending on the configuration of the molded part, multiple parts can be molded within a single mold during a single cycle. For instance, two air return bulkheads can be fabricated simultaneously, each bulkhead being formed by an opposite side of a clam shell type mold. If further additional strength is desired, reinforcing ribs can be included in the mold. Optionally, various additives can be added to increase the part's resistance to ultraviolet light, temperature, heat, flame, or electrostatic charge. As noted above, various inserts may be molded into the part, including rims, handles, or edging made of metal or other suitable materials. Moreover, multiple wall molds can be used that include adjacently situated cavities so that a single molding cycle produces multiple parts or pieces.
[0049] In a preferred embodiment, the wall thickness is about an eighth of an inch. Glass fibers having a length of about 9/16″ are molded into the polyethylene wall. A fraction of the fibers protrude into the internal cavity up to about half and inch, depending on the degree to which they are embedded into the polyethylene. Some of the fibers are completely encapsulated by the polyethylene.
[0050] The panels of are preferably fabricated accordingly the following protocol. A commercially available aluminum mold was opened and approximately ten pounds of polyethylene powder was added. On top of powder was placed approximately one pound, or ten weight percent, of glass fibers having an approximate length of 9/16″. The mold was then closed, mounted to an arm, and slid into an oven. The mold was rotated at approximately twelve RPM on the horizontal axis and four rpm on the vertical axis. The oven was preheated to about 575 degrees Fahrenheit and the mold was left in the oven for about twenty minutes. Afterwards, the mold was placed at a cooling station for 12-15 minutes. Then the mold was opened and the part was removed from the mold while still warm, about 125 to 150 degrees. While at that approximate temperature, the panel was placed in a foaming press and polyurethane foam injected. The panel was allowed to cool for twenty minutes in foaming press before it was removed.
[0051] Panels manufactured according to the this technique have significantly improved structural integrity. When a standard foam-filled panel is crushed or impacted with a significant force, the shell or face of the panel delaminates from the internal foam. In contrast, the shell of the improved panel shows no observable delamination when crushed, due in substantial part to the mechanical interlock caused by the fibers protruding inwardly from the wall layer. The shell is strongly bonded to the foam because a significant fraction of the glass fibers were bonded securely to both the foam and polyethylene.
[0052] Further details concerning certain aspects of the aforementioned rotomolding technique can be found in Plastics Materials and Processes, Seymour S. Schwartz and Sidney H. Goodman, Van Nostrand Reinhold Company, Inc. (1982); Rotational Molding of Plastics (Polymer Engineering Series 2), 2 d Edition, R. J. Crawford (June 1996); and Rotational Molding: Design, Materials, & Processing, Glen Beal (October 1998); the disclosures of which are herein incorporated by reference in their entirety.
[0053] The edge members 18 of FIG. 1 are shown and described in more detail in FIGS. 8-10 . FIG. 8 depicts the receiving channels 20 formed in the peripheral edges of the bulkhead core 1 . The mounting members 24 can be mitered together as shown in FIG. 9 , whereby the seals 25 are permitted to effectively comb together 38 at the corner of the bulkhead. Other known types of seals may be readily substituted for the wipe- or blade-type seal 25 . For instance, vinyl-encased foam seals may be fastened to the mounting members 24 as shown in FIG. 10 . Optionally, the wipes or foam may be secured to the mounting member without use of mechanical fasteners, as by heat sealing, gluing, or integral molding.
[0054] Significantly, the seals may be easily removed and replaced. The useful life of a bulkhead is often defined by the durability of the peripheral seals. When the seals tear or otherwise degrade, bacteria and other pathogens can infiltrate and subsist within the seal area, thereby greatly increasing the risk of food contamination. Moreover, worn out seals are unable to provide the required insulation between cargo compartments. Due to the difficulty in removing the seals from many previous designs, bulkheads are usually discarded when the seals are worn out. Contrariwise, the seals of the above-described embodiments may be readily removed and cost-effectively replaced with new seals.
[0055] The receiving channels 20 and mounting members 24 can fashioned to have virtually any set of complementary configurations. Hemispherical detents may be formed at the peripheral edge of the panels 10 , 11 and the mounting members 24 may be adapted to include hemispherical protrusions so that the edge member 18 snaps on to the bulkhead core 1 . Alternatively, horizontal ridges may be formed at the peripheral edges of the panels 10 , 11 and complementary splines or ridges may be formed into the mounting members so that the side edge members 18 may slide laterally into place. Any combination of suitable formations, fasteners, and other known fastening means may be used to secure the edge member 18 to the bulkhead core 1 .
[0056] FIGS. 11-12 depict trim members 50 , 51 that can be integrally molded into the panel so that they form the outer edge of the panel. FIG. 12 shows a rigid trim member 51 that, after being integrally molded into the periphery of the bulkhead, serves as a rigid mount for the wipe seals and other edge members heretofore described. In such an embodiment, the trim member 51 effectively replaces the peripheral portion of the panel 10 that includes the integrally molded channels 20 (shown in FIG. 8 ). FIG. 11 shows another rigid trim member 50 that can be adapted to serve as a hinge plate. Hinges made of polymer, vinyl, fabric, rubber, metal or other suitable material can be connected to two proximally disposed rigid trim members. A polymeric or other suitable sheeting member can be laid across the face one trim member and then attached to the trim member by pushing a rod or post into the circular trim cavity. The sheeting member traverses the face 52 of the trim member 50 and then is attached in a like manner to an opposably facing trim member (on an adjacent panel) having the same construction. This arrangement holds the adjacent panel firmly but permits the adjacent panel to pivot through almost a complete 360 degree range.
[0057] FIG. 13 depicts an adjustable edge member comprised of two adjustable members, 26 a , 26 b which include receiving channels 20 that slideably engage with the previously described mounting members 24 . Mounting flanges 27 are adapted to be secured to the bulkhead core 1 . The adjustable members 26 a and 26 b of FIG. 13 slideably and reciprocally engage one another so as to permit the adjustable members 26 to be readily moved during manufacturing operation from an open position to a fully closed position (shown in FIG. 13 ). The adjustable members can be partially closed so as to accommodate bulkhead cores 1 of varying thicknesses. After the adjustable members 26 a,b are closed to the desired thickness, the mounting flanges 27 are securing to the panels 10 , 11 according to known means such as adhesives, mechanical fasteners, and the like.
[0058] A number of embodiments of the present invention have been described. Nevertheless, it will be understood that various additional modifications may be made without departing from the spirit and scope of the invention. Accordingly, other embodiments are within the scope of the following claims.
|
Improved panels suitable for use in bulkhead and partition systems. In one embodiment of the invention, the panels are seamless, one-piece members integrally formed from a single resinous material. In other embodiments, the panels include depressions that obviate the need to fill the panels with foam or other supportive filler material. In still other embodiments, the panels have no fasteners extending through panel so the panels are substantially impervious to moisture. Other embodiments have grooves or similar mounting means disposed around their peripheral edges to which edging such as supports or flexible seals may be mounted. In yet other embodiments, the grooves are arranged so as to permit worn out seals to be quickly and easily replaced without the need to remove mechanical fasteners.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a division of prior application Ser. No. 11/939,968 filed on Nov. 14, 2007, which prior application claims the benefit under 35 USC §§119 and 365 of the filing date of prior International Application No. PCT/US06/60926, filed Nov. 15, 2006. The entire disclosures of these prior applications are incorporated herein by this reference.
BACKGROUND
The present invention relates generally to equipment utilized and operations performed in conjunction with a subterranean well and, in an embodiment described herein, more particularly provides a well tool including a swellable material and an integrated fluid for initiating swelling of the swellable material.
Well packers and other types of well tools are known which use swellable materials. These swellable materials swell when they are contacted by a certain type of fluid. For example, a swellable material may swell when it is contacted by a hydrocarbon fluid, gas, water, etc.
If the particular fluid which causes swelling of the swellable material is not present in a well when it is desired for the material to swell, then the fluid can be circulated through the well to the material, for example, by spotting the fluid at the depth of the well tool.
Unfortunately, this method has certain disadvantages. For example, the fluid can migrate away from the well tool (e.g., if the fluid which causes the swellable material to swell has a different density or viscosity as compared to the remainder of the fluid in the well), and over the longer term the fluid will not be present to maintain the swollen condition of the swellable material.
Therefore, it may be seen that improvements are needed in the art of constructing well tools utilizing swellable materials, and swelling those materials in conjunction with well operations.
SUMMARY
In carrying out the principles of the present invention, well tools and associated methods are provided which solve at least one problem in the art. One example is described below in which a well tool is provided with an integral fluid reservoir for supplying fluid to a swellable material. Another example is described below in which fluid is supplied to a swellable material of a well tool to cause the material to swell while the material is in an environment containing another fluid which does not cause the material to swell.
In one aspect, a well tool is provided which includes a swellable material and a reservoir for containing a fluid of a type which causes the first swellable material to swell. Preferably, the reservoir is included as an integral part of the well tool, either by being internal to the swellable material, or by being positioned adjacent to the swellable material.
In another aspect, a method of swelling a swellable material included in a well tool is provided. The method includes the steps of: positioning the well tool in a well; and then activating a fluid to cause swelling of the swellable material. The fluid may be activated in various different ways, for example, by passage of time, by varying pressure, increasing temperature, applying force, etc.
In yet another aspect, a method of swelling a swellable material includes the steps of: providing the swellable material which is capable of swelling when contacted by a fluid; positioning the swellable material in an environment in which the swellable material is contacted by another fluid which does not cause the material to swell; and swelling the swellable material by contacting the swellable material with the first fluid while the swellable material remains in contact with the other fluid.
These and other features, advantages, benefits and objects of the present invention will become apparent to one of ordinary skill in the art upon careful consideration of the detailed description of representative embodiments of the invention hereinbelow and the accompanying drawings, in which similar elements are indicated in the various figures using the same reference numbers.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic partially cross-sectional view of a well system and associated method embodying principles of the present invention; and
FIGS. 2-18 are schematic cross-sectional views of alternate configurations of well tools for use in the well system of FIG. 1 .
DETAILED DESCRIPTION
It is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as inclined, inverted, horizontal, vertical, etc., and in various configurations, without departing from the principles of the present invention. The embodiments are described merely as examples of useful applications of the principles of the invention, which is not limited to any specific details of these embodiments.
In the following description of the representative embodiments of the invention, directional terms, such as “above”, “below”, “upper”, “lower”, etc., are used for convenience in referring to the accompanying drawings. In general, “above”, “upper”, “upward” and similar terms refer to a direction toward the earth's surface along a wellbore, and “below”, “lower”, “downward” and similar terms refer to a direction away from the earth's surface along the wellbore.
Representatively illustrated in FIG. 1 is a well system 10 and associated method which embody principles of the present invention. In the well system 10 , a tubular string 12 is installed in a wellbore 14 . In this example, the wellbore 14 is lined with casing 16 and cement 18 , but the wellbore could instead be unlined or open hole in other embodiments.
The tubular string 12 includes well tools 20 and 22 . The well tool 20 is depicted as being a packer assembly, and the well tool 22 is depicted as being a valve or choke assembly. However, it should be clearly understood that these well tools 20 , 22 are merely representative of a variety of well tools which may incorporate principles of the invention.
The well tool 20 includes a swellable material 24 for use as an annular seal to selectively prevent flow through an annulus 26 formed between the tubular string 12 and the casing 16 . Swellable materials may be used as seals in other types of well tools in keeping with the principles of the invention.
For example, another type of swellable seal is described in U.S. application Ser. No. 11/407,848, filed Apr. 20, 2006 for regulating flow through a well screen. The entire disclosure of this prior application is incorporated herein by this reference.
The well tool 22 includes a flow control device 28 (such as a valve or choke, etc.) and an actuator 30 for operating the flow control device. Swellable materials may be used in other types of actuators for operating other types of well tools.
For example, actuators using swellable materials for operating well tools are described in U.S. application Ser. No. 11/407,704, filed Apr. 20, 2006. The entire disclosure of this prior application is incorporated herein by this reference.
The swellable material used in the well tools 20 , 22 swells when contacted by an appropriate fluid. The term “swell” and similar terms (such as “swellable”) are used herein to indicate an increase in volume of a swellable material.
Typically, this increase in volume is due to incorporation of molecular components of the fluid into the swellable material itself, but other swelling mechanisms or techniques may be used, if desired. Note that swelling is not the same as expanding, although a seal material may expand as a result of swelling.
For example, in some conventional packers, a seal element may be expanded radially outward by longitudinally compressing the seal element, or by inflating the seal element. In each of these cases, the seal element is expanded without any increase in volume of the seal material of which the seal element is made. Thus, in these conventional packers, the seal element expands, but does not swell.
The fluid which causes swelling of the swellable material could be water and/or hydrocarbon fluid (such as oil or gas). The fluid could be a gel or a semi-solid material, such as a hydrocarbon-containing wax or paraffin which melts when exposed to increased temperature in a wellbore. In this manner, swelling of the material could be delayed until the material is positioned downhole where a predetermined elevated temperature exists. The fluid could cause swelling of the swellable material due to passage of time.
Various swellable materials are known to those skilled in the art, which materials swell when contacted with water and/or hydrocarbon fluid, so a comprehensive list of these materials will not be presented here. Partial lists of swellable materials may be found in U.S. Pat. Nos. 3,385,367 and 7,059,415, and in U.S. Published Application No. 2004-0020662, the entire disclosures of which are incorporated herein by this reference.
The swellable material may have a considerable portion of cavities which are compressed or collapsed at the surface condition. Then, when being placed in the well at a higher pressure, the material is expanded by the cavities filling with fluid.
This type of apparatus and method might be used where it is desired to expand the material in the presence of gas rather than oil or water. A suitable swellable material is described in International Application No. PCT/NO2005/000170 (published as WO 2005/116394), the entire disclosure of which is incorporated herein by this reference.
It should, thus, be clearly understood that any swellable material which swells when contacted by any type of fluid may be used in keeping with the principles of the invention.
Referring additionally now to FIG. 2 , an enlarged scale schematic cross-sectional view of one possible configuration of the well tool 20 is representatively illustrated. The well tool 20 is used for convenience to demonstrate how the principles of the invention may be beneficially incorporated into a particular well tool, but any other type of well tool may utilize the principles of the invention to enable swelling of a swellable material of the well tool.
As depicted in FIG. 2 , the swellable material 24 is positioned on a generally tubular mandrel 32 . The swellable material 24 could, for example, be adhesively bonded to the mandrel 32 , or the swellable material could be otherwise secured and sealed to the mandrel.
Multiple relatively small reservoirs 34 are formed internally within the swellable material 24 . Although the reservoirs 34 are illustrated in FIG. 2 as being spherical in shape, the reservoirs 34 may be formed as cavities having any desired shape.
The reservoirs 34 may be formed when the swellable material 24 is manufactured, or they may be formed in the material afterward. The reservoirs 34 could extend longitudinally, circumferentially, radially, or in any other direction or combination of directions.
The reservoirs 34 each contain a fluid 36 which causes the material 24 to swell. In this manner, the material 24 may be externally in contact with another fluid 38 which does not cause the material to swell, but the material will still swell because the fluid 36 is internally available to the material.
For example, in the well system 10 of FIG. 1 , the annulus 26 may be filled with the fluid 38 which does not cause the material 24 to swell. However, the material 24 can still be made to swell due to the fluid 36 being in contact with the material.
In one embodiment, the fluid 36 could initially be in a solid form, such as a wax or paraffin, and after the well tool 20 is installed in the well the increased temperature in the well will melt and liquefy the wax or paraffin, so that it is available to cause swelling of the material 24 .
In another embodiment, the fluid 36 could be a gas, and after the well tool 20 is installed in the well the increased pressure in the well will cause the gas to penetrate and swell the material 24 .
In any of these embodiments, the fluid 36 and/or material 24 may be designed so that the fluid 36 causes swelling of the material upon passage of a predetermined amount of time.
Of course, other types of fluids may be used in the well tool 20 of FIG. 2 in keeping with the principles of the invention. Furthermore, any number and size of the reservoirs 34 may be used to contain the fluid 36 .
Referring additionally now to FIG. 3 , an alternate configuration of the well tool 20 is representatively illustrated. In this configuration, only a single reservoir 34 is used, with the reservoir being formed as an internal chamber in the swellable material 24 . Another difference between the configurations of FIGS. 2 & 3 is that the FIG. 3 configuration includes a way to apply annular pressure to the reservoir 34 and compensate for dissipation of the fluid 36 into the material 24 .
A passage 40 is formed through the material 24 and an end ring 42 . The passage 40 provides for fluid communication between the annulus 26 and another chamber 44 formed in the material 24 .
A pressure equalizing device 46 (such as a floating piston, a membrane, etc.) separates the annulus fluid 38 from the fluid 36 in the reservoir 34 , while transmitting pressure from the annulus 26 to the reservoir. In this manner, pressure in the annulus 26 is available to pressurize the fluid 36 and “drive” the fluid into the material 24 if needed, and the fluid 38 can enter the chamber 44 as the fluid 36 dissipates into the material 24 .
Referring additionally now to FIG. 4 , a portion of the swellable material 24 is representatively illustrated in further enlarged scale from another alternate configuration of the well tool 20 . The portion of the swellable material 24 illustrated in FIG. 4 includes the reservoir 34 which, in this embodiment, does not include the pressure transmitting and equalizing features described above for the configuration of FIG. 3 .
Instead, the configuration of FIG. 4 includes features which prevent collapse or other deformation of the reservoir 34 when the fluid 36 is dissipated into the material 24 . For this purpose, a porous material 48 (such as a wire mesh) is positioned between the material 24 and a support structure 50 (such as a helically wound flat wire spring) in the reservoir 34 .
The porous material 48 permits the fluid 36 (not shown in FIG. 4 ) to contact the material 24 , but prevents extrusion of the material between the wraps of the support structure 50 . The structure 50 prevents deformation of the reservoir 34 as the fluid 36 dissipates into the material 24 .
Of course, other types of porous materials and support structures may be used in keeping with the principles of the invention. Furthermore, porous materials and support structures may be used in the other configurations of the well tool 20 described herein, for example, in the reservoir 34 in the configuration of FIG. 3 .
Referring additionally now to FIG. 5 , another alternate configuration of the well tool 20 is representatively illustrated. In this configuration, the reservoir 34 is positioned in the end ring 42 , and a passage 52 is formed to provide fluid communication between the reservoir and the swellable material 24 .
Another difference in the configuration of FIG. 5 is that the well tool 20 includes additional swellable materials 54 , 56 . The swellable material 54 provides sealing between a generally tubular sleeve 58 and the mandrel 32 , and the swellable material 56 provides sealing between the end ring 42 and the mandrel.
The swellable materials 54 , 56 may be made of the same material as the swellable material 24 , or one or both of the materials 54 , 56 may be different from the material 24 . The swellable materials 24 , 54 and the sleeve 58 may be installed on the mandrel 32 in the manner described in International Application No. PCT/US06/035052, filed Sep. 11, 2006, entitled Swellable Packer Construction, having Agent File Reference 021385U1PCT (which corresponds to U.S. application Ser. No. 11/852,295 filed Sep. 8, 2007), and the entire disclosure of which is incorporated herein by this reference.
If the swellable material 54 is different from the swellable material 24 or 56 , then one or more separate reservoirs 60 may be used to contain an appropriate fluid 64 for causing swelling of the material 54 . A passage 62 may provide fluid communication between the reservoir 60 and the swellable material 54 .
Similarly, if the swellable material 56 is different from the swellable material 24 or 54 , then one or more separate reservoirs 66 may be used to contain an appropriate fluid 68 for causing swelling of the material 56 . A passage 70 may provide fluid communication between the reservoir 66 and the swellable material 56 .
Preferably, the swellable materials 24 , 54 , 56 are made of the same type of material, and the fluids 36 , 64 , 68 are the same type of fluid. Accordingly, note that in FIG. 5 additional passages 72 , 74 are provided to permit fluid communication between the reservoirs 36 , 64 and the swellable material 56 .
Plugs 76 may be provided to enable filling the reservoirs 34 , 60 , 66 in the end ring 42 . Set screws 78 (such as carbide-tipped set screws) may be provided to secure the end ring 42 to the mandrel 32 .
Referring additionally now to FIGS. 6 & 7 , another alternate configuration of the well tool 20 is representatively illustrated. In this configuration, multiple reservoirs 34 are formed in a housing 80 threadedly attached between the end ring 42 and another housing 82 having the swelling material 56 therein.
A cross-sectional view of the housing 80 is representatively illustrated in FIG. 7 . In this view, it may be seen that four of the reservoirs 36 are formed in the housing 80 , and that the set screws 78 are installed through the housing between the reservoirs. Of course, any number of reservoirs 34 may be used in keeping with the principles of the invention.
In this embodiment, the swellable materials 24 , 54 , 56 are made of the same type of material, and so in FIG. 6 it may be seen that one or more passages 84 provide fluid communication between the reservoirs 34 and each of the swellable materials. However, if the swellable materials 24 , 54 , 56 required different fluids 36 , 64 , 68 to cause swelling of respective different materials, then separate passages could be provided between the materials and separate reservoirs containing the respective different fluids.
Furthermore, note that although separate passages 86 , 88 are formed in the swellable materials 54 , 24 for communication with the passage 84 on either side of the sleeve 58 , the sleeve is also perforated to allow fluid communication through the sleeve. This feature could also be incorporated into any of the other configurations of the well tool 20 described herein.
Referring additionally now to FIGS. 8 & 9 , another alternate configuration of the well tool 20 is representatively illustrated. In this configuration, the reservoir 34 is formed as an annular chamber within the interior of the swellable material 24 . The passages 86 , 88 extend into the swellable material 24 to provide adequate distribution of the fluid 36 to the material.
As depicted in FIG. 9 , a series of the passages 86 , 88 are circumferentially distributed in the swellable material 24 . Eight of each of the passages 86 , 88 are shown in FIG. 9 , but any number or arrangement of the passages may be used in keeping with the principles of the invention. In addition, the passages 86 , 88 may extend any distance in the material.
Referring additionally now to FIGS. 10 & 11 , another alternate configuration of the well tool 20 is representatively illustrated. This configuration is similar in many respects to the configuration of FIGS. 8 & 9 , except that passages 90 which provide fluid communication between the reservoir 34 and the swellable material 24 are formed only partially in the material.
The passages 90 are also bounded radially inwardly by the mandrel 32 . Note that the passages 90 could also, or alternatively, be formed on or in the mandrel 32 , if desired.
Referring additionally now to FIG. 12 , another alternate configuration of the well tool 20 is representatively illustrated. In this configuration, the reservoir 34 is formed in the end ring 42 and the pressure equalizing device 46 separates the reservoir from the chamber 44 which is also formed in the end ring.
The configuration of FIG. 12 is somewhat similar to the configuration of FIG. 3 , except that the reservoir 34 and chamber 44 are formed in the end ring 42 , instead of in the swellable material 24 . Accordingly, one or more passages 92 are used to provide fluid communication between the reservoir 34 and the interior of the swellable material 24 . The passages 92 may extend any distance into the material 24 .
Referring additionally now to FIG. 13 , another alternate configuration of the well tool 20 is representatively illustrated. This configuration is very similar to the configuration of FIG. 12 , except that two sets of the end rings 42 with the reservoir 34 and chamber 44 therein are used, with one at each opposite end of the swellable material 24 .
Referring additionally now to FIG. 14 , another alternate configuration of the well tool 20 is representatively illustrated. This configuration is very similar to the configuration of FIG. 13 , except that the passages 92 are formed completely through the swellable material 24 and interconnect the reservoirs 34 .
Referring additionally now to FIG. 15 , another alternate configuration of the well tool 20 is representatively illustrated. This configuration is very similar to the configuration of FIGS. 13 & 14 , except that the upper reservoir 34 is used to supply the fluid 36 to the swellable material 24 , and the lower reservoir 34 is used to supply the fluid 36 to the swellable material 54 separated from the material 24 by the sleeve 58 (as in the configurations of FIGS. 5 & 6 ).
Of course, if the material 24 is different from the material 54 then different fluids 36 , 64 may be used to cause swelling of the respective materials, as described above.
Another difference in the configuration of FIG. 15 is that flow control devices 94 , 96 are used to determine when the reservoirs 36 are pressurized by the fluid 38 in the annulus 26 . As depicted in FIG. 15 , the flow control devices 94 , 96 are in the form of rupture discs which rupture when a predetermined pressure is applied to the annulus 26 , but other types of flow control devices (such as valves, eutectic devices which melt at a predetermined temperature, flow control devices such as sliding sleeves which operate in response to application of mechanical force, etc.) may be used in keeping with the principles of the present invention.
Referring additionally now to FIG. 16 , another alternate configuration of the well tool 20 is representatively illustrated. In this configuration, a flow control device 98 (similar to the flow control devices 94 , 96 described above) is positioned between the reservoir 34 and the passage 92 .
In this manner, the fluid 36 is not permitted to contact the material 24 until the flow control device 98 is opened. This allows swelling of the material 24 to be delayed until such swelling is desired (for example, after the well tool 20 has been appropriately positioned downhole in a well), at which time a predetermined pressure, temperature, force, etc. may be applied to cause the flow control device 98 to open and permit fluid communication between the reservoir 34 and the interior of the material.
Note that the flow control devices 94 , 96 , 98 depicted in FIGS. 15 & 16 may be used in any of the other configurations of the well tool 20 described herein to control application of pressure to the reservoir 34 , and/or to control fluid communication between the reservoir and the swellable material 24 or a passage in communication with the material.
Referring additionally now to FIG. 17 , another alternate configuration of the well tool 20 is representatively illustrated. This configuration is similar in many respects to the configuration of FIG. 8 . However, in the configuration of FIG. 17 , the reservoir 34 is collapsible, in order to allow for pressure equalization between the interior of the reservoir and the exterior of the tool 20 as the fluid 36 is dispersed into the material 24 .
To permit the reservoir 34 to collapse, an outer wall 102 of the reservoir is relatively thin and flexible. The outer wall 102 , thus, functions as a flexible membrane and pressure equalizing device between the reservoir 34 and the exterior of the tool 20 .
As the fluid 36 is dispersed into the material 24 , the outer wall 102 will deflect inward, thereby allowing the volume of the reservoir 34 to decrease without creating a “negative” pressure differential which would hinder further dispersal of the fluid into the material. A rigid wall 104 is preferably provided between the reservoir 34 and the material 24 , so that collapse of the reservoir is unaffected by the swelling of the material and vice versa.
Referring additionally now to FIG. 18 , another alternate configuration of the well tool 20 is provided in which the reservoir 34 is collapsible. This configuration is similar in many respects to the configuration of FIG. 12 . However, in the configuration of FIG. 18 , the pressure equalization device 46 is not a piston, but instead is a flexible membrane or bag in which the fluid 36 is contained.
As the fluid 36 is dispersed into the material 24 , the device 46 collapses, thereby allowing the volume of the reservoir 34 to decrease without creating a “negative” pressure differential which would hinder further dispersal of the fluid into the material. A flow control device 106 is provided to regulate flow into the chamber 44 . The flow control device 106 could be, for example, a check valve (such as a spring-loaded check valve, flexible sealing washer, etc.), another type of one-way valve (such as a one-way lip seal), a one-way pressure equalizing valve, etc.
It may now be fully appreciated that the well tool 20 described above in its various configurations provides for swelling of the swellable materials 24 , 54 , 56 , even though the materials are positioned in an environment in which the fluid 38 therein does not cause swelling of the materials. The well tool 20 includes at least one swellable material 24 and at least one reservoir 34 for containing a fluid 36 of a type which causes the swellable material to swell. The fluid 36 is at least one of a gas, gel, liquid, hydrocarbon fluid and water. The fluid 36 could be a solid material which liquefies at a predetermined elevated temperature. The reservoir 34 is in fluid communication with the swellable material 24 .
The reservoir 34 may be collapsible. A flow control device 106 may equalize pressure between an interior of the reservoir 34 and a pressure source exterior to the reservoir.
A flow control device 98 may selectively permit fluid communication between the reservoir 34 and the swellable material 24 . The reservoir 34 may be positioned within the swellable material 24 , or the reservoir may be positioned external to the swellable material.
The well tool 20 may include a second reservoir 34 , 60 , 66 . The second reservoir may also contain the fluid 36 , or it may contain another type of fluid 64 , 68 . The second reservoir may be fluid communicable with the swellable material 24 , or with another swellable material 54 , 56 .
The fluid 36 may be activated to cause the swellable material 24 to swell in response to passage of time or application of at least one of heat, pressure and force. The fluid 36 may be operable to cause the swellable material 24 to swell when the well tool 20 is immersed in another fluid 38 which does not cause the swellable material to swell. The swellable material 24 may be included in an actuator 30 of a well tool 22 , so that swelling of the swellable material is operable to actuate the well tool.
Of course, a person skilled in the art would, upon a careful consideration of the above description of representative embodiments of the invention, readily appreciate that many modifications, additions, substitutions, deletions, and other changes may be made to the specific embodiments, and such changes are contemplated by the principles of the present invention. Accordingly, the foregoing detailed description is to be clearly understood as being given by way of illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims and their equivalents.
|
A well tool including swellable material and integrated fluid for initiating swelling. A well tool includes a swellable material and a reservoir for containing a fluid of a type which causes the swellable material to swell. A method of swelling a swellable material included in a well tool includes the steps of: positioning the well tool in a well; and then activating a fluid to cause swelling of the swellable material. A method of swelling a swellable material includes the steps of: providing the swellable material which is capable of swelling when contacted by a fluid; positioning the swellable material in an environment in which the swellable material is contacted by another fluid which does not cause the material to swell; and swelling the swellable material by contacting the swellable material with the first fluid while the swellable material remains in contact with the other fluid.
| 4
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to converting subsurface currents into electricity and, in particular, to conversion using a coil and magnetic element.
2. Description of Related Art
It is the experience of many who have gone to the seashore and stood in the water perhaps 10-50 yards from the water's edge that there is an extremely powerful alternating inflow and outflow of water 1-5 feet beneath the surface. This ebb and flow of water occurs about 4 times per minute and has tremendous kinetic energy.
In the past 50 years a number of different devices have been designed to try to harness the kinetic energy of moving ocean water in usable ways.
Tidal
Some energy conversion devices have relied on positioning at flood plains, such as those at the Bay of Fundy on the eastern coast of Canada or St. Malo on the Brittany Coast in France (across the La Rance Estuary). In these locations, there is a powerful inflow of water for a period of perhaps a few hours followed by a similar outflow of water for a similar period of time (“the tide comes in” and “the tide goes out”) each twice daily. Machinery at these locations requires huge capital investments, dam constructions, and other unsightly changes to the natural beauty of the sea.
Current
Some energy conversion devices have relied on positioning at the mouth of rivers or in the path of well-known ocean currents (really “current” generators erroneously called “tidal” generators) to supply a steady one-way directional source of moving water to turn turbines and other devices that then generate electricity.
These first two types of devices generally employ underwater propeller-like turbine wheels of various kinds to either generate electricity directly, or to mechanically transfer the turbine motion to a surface generator, or to run a pump to elevate water and thereby allow it to be used at some future time in a way similar to the generation of electricity at a hydroelectric dam.
Wave
Recently, instead of turbines, snake-like devices have been designed that feature multiple hinges (See New York Times Aug. 3, 2006, Pages C1 and C4) to allow the water to “whip” the device as it floats on the ocean's surface. These devices are not located to take advantage of subsurface back and forth motion of water, but rather are positioned as floating machinery miles off shore. They are surface wave devices. The motion at the joints of the device is harnessed to power small electric motors. Current designs of this device ride on the surface of the ocean where they are visible; not below the surface. These snake-like devices must be anchored to the ocean floor to work efficiently and to prevent them from drifting into land and being damaged. They are very confined mechanical devices that will eventually undergo fatigue and break.
Other wave energy conversion devices depend on buoys that contain magnets and float on the ocean surface within vertical cylindrical canisters that are in turn wrapped with copper wire. A linear electric generator is effectively created generating electricity by the action of fluctuating magnetic fields within the coil of copper wire. These are also wave machines that are positioned out to sea and do not take advantage of the subsurface back and forth motion of water. This method relies upon the “choppiness” of the surface water to operate efficiently; if the ocean is “calm”, only small amounts of electricity are generated.
Geothermal
Geothermal devices are used to harness the energy of underwater volcanoes and pipes driven deep into the ocean floor. These devices convert thermal energy and not mechanical energy into electricity.
Energy conversion patents include U.S. Pat. Nos. 1,439,984; 3,696,251; 4,291,234; 4,843,249; 4,864,152; 5,105,094; 5,440,176; 6,020,653; 6,729,744; 6,955,049; 7,012,340; and 7,042,112. See also www.aw-energy.com (unknown publication date) and “Permanent magnet fixation concepts for linear generator” by Oskar Danielsonn, et. al. Uppsala University, UPPSALA (unknown publication date).
SUMMARY OF THE INVENTION
In accordance with the illustrative embodiments demonstrating features and advantages of the present invention, there is provided a generator for converting into electricity the energy from subsurface currents having horizontally moving components. The generator has a submergible electrical coil adapted to allow subsurface currents to enter and flow axially through the coil. Also included is a support adapted to engage a sea floor and to support and orient the electrical coil to allow horizontal components of subsurface currents to produce an axial flow through the coil. The generator also includes a magnetic shuttle mounted to longitudinally reciprocate in the coil, driven by water flowing through the coil.
In accordance with another aspect of the invention, a method is provided that employs a magnetic shuttle and an electrical coil for converting into electricity the energy from subsurface currents having horizontally moving components. The method includes the step of submerging the electrical coil above a sea floor to allow horizontal components of subsurface currents to produce an axial flow through the coil. The method includes the step of placing the magnetic shuttle in the coil to longitudinally reciprocate, driven by water flowing through the coil.
In accordance with yet another aspect of the invention, a method is provided that employs a plurality of magnetic shuttles and a parallel plurality of electrical coils. The method can convert into electricity the energy from subsurface currents having horizontally moving components. The method includes the step of submerging the electrical coils above a sea floor to allow horizontal components of subsurface currents to produce an axial flow through the coils. Another step is allowing subsurface currents to enter and flow axially through the coils. The method includes the step of placing the magnetic shuttles separately into a corresponding one of the coils to longitudinally reciprocate, driven by water flowing through the coils.
By employing apparatus and methods of the foregoing type, an improved generator and method of generating electricity is achieved. In a disclosed embodiment the interior of a hollow plastic shuttle is fitted with a number of longitudinally oriented magnets. A plurality of parallel guide rods surround the shuttle and fit into longitudinal grooves on its outside. These guide rods are supported by a plurality of longitudinally spaced collars mounted in a frame.
Encircling the guide rods between the collars are a number of aligned iron or stainless steel sleeves. Electrical coils are wound around the outside of each of the sleeves and connected in series to form a linear generator. Specifically, subsurface water currents drive the shuttle and its magnets through the electrical coils to induce a voltage. The polarity of the voltage alternates and can be rectified by a full wave bridge located onshore.
In one embodiment this series of electrical coils forms an electrical generator located in one column of a rectangular support frame that also supports a number of identical parallel generators located in adjacent columns. This frame with its multiple generators is rotatably mounted on a vertical beam together with, for example, two more identical frames each having multiple generators.
This beam is mounted on a sea floor at a distance from the shoreline where subsurface currents are fairly strong. The multiple frames mounted on the vertical beam can be azimuthally adjusted so the shuttles of the linear generators are strongly driven by the subsurface currents.
Current from the generators may be sent by cable to an onshore rectifying station. There the alternating current can be rectified into a DC current that is either stored or immediately dispatched to a load or to a local electrical grid.
BRIEF DESCRIPTION OF THE DRAWINGS
The above brief description as well as other objects, features and advantages of the present invention will be more fully appreciated by reference to the following detailed description of illustrative embodiments in accordance with the present invention when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view of a portion of a generator that may be used to generate electricity in accordance with principles of the present invention;
FIG. 2 is an end view of the apparatus of FIG. 1 , partly in section;
FIG. 3 is a longitudinal sectional view of the shuttle of FIG. 1 ;
FIG. 4 is a perspective view of the apparatus of FIG. 1 fitted with a coil and replicated to form a plurality of generators mounted in a frame;
FIG. 5 is a detailed side view of a fragment of the apparatus of FIG. 4 , partly in longitudinal section;
FIG. 6 is a schematic diagram showing the interconnection of coils of FIG. 4 to an onshore rectifier;
FIG. 7 is a perspective view of a number of frames in accordance with FIG. 4 rotatably mounted on an upright beam; and
FIG. 8 is an elevational view of the apparatus of FIG. 7 mounted on a sea floor and connected by a cable to an onshore rectifier.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-3 , shuffle 10 has a generally cylindrical midsection 16 A between tapered frustoconical ends 16 B (collectively referred to as case 16 ). Cylindrical midsection 16 A has a central chamber 18 A with six cylindrical cavities 18 B circumferentially and equiangularly spaced about the longitudinal axis of shuttle 10 .
Cylindrical cavities 18 B each hold a cylindrical magnetic element 12 . Elements 12 are rods made of rare earth magnets (or other magnetic material) oriented with all their north-south poles oriented in the same way. Magnetic elements 12 are in the illustrated embodiment approximately 4 inches (10 cm) in diameter and 3.5 feet (1 m) in length. In some embodiments, magnetic elements 12 may have a different size and shape, such as triangular or rectangular prisms with a different overall size. Consequently, cavities 18 B may have alternative complementary shapes and sizes to accommodate different magnetic elements.
The outer surface of midsection 16 A has six equiangularly spaced longitudinal grooves 22 that extend partially into frustoconcial ends 16 B. The depth of each groove 22 is substantially consistent along the length of midsection 16 A. Grooves 22 become increasingly shallow as they extend along the tapered surfaces of ends 16 B before terminating approximately half way.
Each frustoconical end 16 B has an interior cavity that communicates with central cavity 18 A. Case 16 is integrally molded of transparent hard plastic but may be made of other materials as well. In this embodiment, case 16 is approximately 4 feet (1.22 m) in length and 15 inches (38 cm) in diameter, but in other embodiments may be sized differently. The case 16 of shuttle 10 may be assembled from two or more parts to facilitate disassembly and maintenance of shuttle 10 , including the retrieval of magnetic elements 12 from a worn or damaged case.
A valve 20 is located in one of frustoconcial ends 16 B. Valve 20 may be used to evacuate the inside of shuttle 10 or introduce a gas, such as helium or nitrogen to render shuttle 10 substantially buoyant-neutral when submerged.
Referring to FIGS. 1 and 2 , collar 26 is an annulus with six pairs of opposing fingers 31 circumferentially spaced about the inner diameter of the collar. The fingers 31 of each pair protrude inward and curve together thereby forming a circular receptacle for holding guide rods 24 (which will be described in further detail hereinafter).
Two substantially rectangular mounting flanges 29 protrude in opposite directions horizontally. Two additional mounting flanges 28 protrude in opposite vertical directions. When viewed edgewise, lower flange 28 appears J-shaped and upper flange 28 appears inverted J-shaped. Located in each of the four mounting flanges 28 and 29 are a pair of fastener holes 30 for mounting collar 26 in a manner to be described presently. Collar 26 may be made of a flexible composite material but may be made of other materials such as plastic or aluminum.
Referring to FIG. 4 , frame 37 is constructed with an upper rectangular grid made of eight parallel, evenly spaced, longitudinal members 41 A- 41 H intersecting six parallel, evenly spaced, transverse members 33 A- 33 F. Frame 37 also has a lower rectangular grid with eight, parallel, evenly spaced, longitudinal members 34 A- 34 H intersecting six, parallel, evenly spaced, transverse members 32 A- 32 F. The upper and lower grids are similar, each having matching intersections interconnected by upright members 38 , with (a) the uprights on one side distinguished as upright members 38 A and (b) the uprights on the opposite side distinguished as upright members 38 B. These intersections and upright members 38 (and 38 A and 38 B) may be connected by welding, bolting, fastening brackets, or other means.
Longitudinal members 41 A- 41 H and 34 A- 34 H are made of square or round non-magnetic stock approximately 15 feet (4.6 m) in length. Transverse members 32 A- 32 F and 33 A- 33 F are also made of similar stock approximately 12 feet (3.7 m) in length. These lengths are merely exemplary.
Arranged in this fashion, frame 37 has seven transversely spaced, longitudinal columns 100 , 102 , 104 , 106 , 108 , 110 , and 112 each divided into 5 longitudinally spaced segments forming five rows delineated by transverse members 33 A- 33 F (and members 32 A- 32 F).
Previously mentioned collar 26 is installed on the two vertical members 38 A, the bottom member 32 A, and the top member 33 A in column 100 in the following manner: The two J-shaped flanges 28 are flexible enough to spread open and snap over members 32 A and 33 . Flanges 28 and as well as flanges 29 are then fastened to frame 37 using screws inserted through openings 30 of the flanges, although other fastening means are contemplated such as bolts, rivets, adhesive, etc. (Note, fastening of one of the flanges 29 may be deferred until installation of its neighboring collar, at which time a common fastener can be used for both.)
In a similar manner five more collars 26 may be installed in column 100 on transverse members 33 B- 33 F, 32 B- 32 F, and vertical members 38 , and 38 B. Coil segments 36 A- 36 E will be installed in column 100 between collars 26 in a manner to be described presently.
Referring to FIG. 5 , coil segment 36 A of FIG. 4 is represented schematically (coil segments 36 B- 36 F of FIG. 4 being identical). Coils segment 36 A is approximately 3 feet (0.9 m) long and is formed of multiple turns of Formvar coated copper wire 50 wound about cylindrical iron sleeve 53 , which has an inside diameter of approximately 16.5 inches (42 cm). In various embodiments, different insulations may be used and the wire gauge can be adjusted as needed (smaller gauge numbers tending to be more efficient).
Optional low reluctance cylindrical rods 23 that serve as flux return paths are circumferentially spaced about coil 50 . (In FIG. 4 these rods 23 are shown in phantom.) Rods 23 are radially spaced from and parallel to magnetic elements 12 of shuttle 10 . Rods 23 are approximately 2 inches (5.1 cm) in diameter and 15 feet (5.7 m) in length but may be other sizes as well. Rods 23 are made of stainless steel but may be made of other low reluctance materials possibly having a protective coating to withstand prolonged submersion in ocean water.
Lines of flux 54 project from magnetic rods 12 and magnetize iron sleeve 53 to have the same north-south orientation. These lines of flux curve outward crossing numerous turns of wire 50 before traveling through low reluctance rods 23 (or through ambient if no return rods are used). Lines of flux 54 extend longitudinally through rods 23 before curving inward and re-entering the magnetic rods 12 . In embodiments where rods 23 are not used, lines of flux 54 may curve outward a greater distance from rod 12 as they flow between the north and south poles of rod 12 .
Referring again to FIGS. 2 and 4 , coil segment 36 A is placed in column 100 between the two longitudinally spaced collars 26 mounted on transverse members 32 A and 32 B. Each of six guide rods 24 are then inserted between each pair of fingers 31 of the collar 26 attached to transverse member 32 A. These six rods 24 are then pushed through coil 36 A to slide into the space between each pair of fingers 31 of the collar 26 mounted on transverse member 32 B. Coil segment 36 B is then placed between the collars 26 mounted on transverse members 32 B and 32 C. Each of rods 24 are then pushed through coil segment 36 B and between each pair of fingers 31 of collar 26 on member 32 C. The process is repeated for coil segments 36 C- 36 E.
Rods 24 can be further secured with mounting brackets (not shown) or by being welded or glued in place. Guide rods 24 are in this embodiment 2 inches (5.1 cm) in diameter and 15 feet (4.6 m) long. Rods 24 are sized to engage grooves 22 of shuttle 10 and are made of composite material but may be made of other non-ferromagnetic materials as well.
Shuttle 10 is then inserted into coil segment 36 A through the collar 26 mounted on member 32 A. Grooves 22 of shuttle 10 ride on guide rods 24 . (Note that in some embodiments, more than one shuttle 10 may be inserted.)
Previously mentioned low reluctance rods 23 (shown also in FIG. 5 ) may be optionally installed in column 100 by inserting them through openings 23 in collars 26 . Some embodiments will have a number of rods different from six or the rods may be replaced with a cylindrical sleeve
Annular end plate 49 is designed to overlay collar 26 on member 32 A. End plate 49 has four substantially rectangular mounting flanges 51 protruding radially outward therefrom at the 3, 6, 9 and 12 o'clock positions. One of four tabs 42 protrude inwardly to cover the ends of four of the six guide rods 24 . A cross bar 43 covers the other two guide rods 24 and keeps shuttle 10 from leaving frame 37 . End plate 49 is made of a composite material but may be made of other materials such as plastic or steel. An additional a similar endplate (not shown) is placed over the collar 26 on member 32 F.
The foregoing process of inserting rods 24 , placing coil segments 36 A- 36 E, inserting optional return rods 23 , inserting shuttle 10 , and attaching end plates 40 is repeated for columns 102 , 104 , 108 , 108 , 110 and 112 , resulting in two sets of three linear generators 45 A- 45 F (column 106 is left open for reasons to be described presently).
While five are shown, the number of coil segments forming each of the linear generators 45 A- 45 F may be a different number, typically in the range of two to ten segments. Also, while six are shown, the number of linear generators may be different, typically in the range of two to ten generators.
Referring to FIG. 6 , the previously mentioned coil segments 36 A- 36 E of linear generator 45 A are schematically shown connected in series to form an electrical coil. The coil segments of the other linear generators 45 B- 45 D are similarly connected but only generator 44 F is specifically illustrated. Linear generators 45 A- 45 E are connected in parallel across cables 64 and 66 . In some embodiments, the linear generators 44 A- 44 F may be connected in series.
Cables 64 and 66 travel typically from 50 to 300 (15 to 91 m). feet to onshore rectifier bridge 68 . Cable 66 is connected to the cathode of diode 68 D and the anode of diode 68 A. Terminal +V is connected to the cathodes of diodes 68 A and 68 B. Conductor 64 is connected to the anode of diode 68 B and the cathode of diode 68 C. Terminal GND is connected to the anodes of diodes 68 C and 68 D.
Referring again to FIG. 4 , a detent mechanism 46 is located in column 106 between transverse members 33 C and 33 D (as well as members 32 C and 32 D). Mechanism 46 has an outer race 46 A attached through four diagonal supports 47 to the intersections of longitudinal members 41 D and 41 E and transverse members 33 C and 33 D. Mechanism 46 is also connected through four additional supports (not shown but similar to supports 47 ) to the intersections of longitudinal members 34 D and 34 E and transverse members 32 C and 32 D.
Mechanism 46 has an inner race 46 B with an I-shaped opening extending through it vertically. The outer race 46 A of mechanism 46 may rotate relative to the inner race 46 B before being locked in a desired position. Detent mechanism 46 may alternatively be a lockable, ratcheting mechanism or other lockable device that allows rotation about at least one axis when unlocked and prevents rotation when locked.
Frame 37 is covered on all sides with a wire screen 48 (partially shown) except for gaps for detent mechanism 46 . The mesh of screen 48 is sized to allow ocean water to flow freely in and out of frame 37 while avoiding the entry of small ocean life.
Referring to FIG. 7 , I-beam 70 protrudes from a concrete footing in sea floor 72 . I-beam 70 is made of steel but may alternatively be made of other non-paramagnetic material such as aluminum or composites. Previously mentioned frame 37 is stacked together with two other identical frames 237 and 337 on beam 70 , so the beam extends through the I-shaped openings located in the inner race 46 B of frame 37 as well as the inner races (not shown) for frames 237 and 337 . The inner race of frame 337 rests on a flange (not shown) welded on a lower portion of beam 70 .
Each of frames 37 , 237 and 337 is adjusted azimuthally so that the longitudinal axes of the linear generators (generators 45 A- 45 F of FIG. 4 ) are aligned with the subsurface currents at their location and depth. The longitudinal axes of the generators may be horizontal or somewhat off horizontal to accommodate subsurface currents. In general the subsurface currents will be primarily horizontal or if diverted from horizontal (either long term or transiently) will have a large horizontal component. This large horizontal component ensures that subsurface current will flow into the coils of the linear generators (even if the generators are not exactly horizontal) to drive the shuttle therein.
The three frames 37 , 237 and 337 on beam 70 are collectively referred to as a generator array 76 . Although array 76 is described having three frames 37 , 237 and 337 , a different number of frames may be installed on beam 70 limited only by the height and strength of I-beam 70 .
Referring to FIG. 8 , generator array 76 is shown secured on sea floor 72 approximately 50 to 300 feet (15 to 91 m) from the high water mark on the shore line. The output of each frame of array 76 is electrically connected through cables 64 / 66 to onshore rectifier bridge 68 (see rectifier bridge 68 of FIG. 6 ) located in building 75 . In some cases the outputs of the frames may be connected in series, but parallel connections are contemplated as well. The DC output of the rectifier bridge 68 is transmitted on cable pair 78 .
To facilitate an understanding of the principles associated with the foregoing apparatus, its operation will be briefly described in connection with FIGS. 4-8 . I-beam 70 ( FIG. 7 ) is mounted in sea floor 72 at a predetermined location from a shoreline where the waves produce a back and forth subsurface current of ocean water. The depth and distance where beam 70 is located should be such that its top is submerged most of time, only occasionally breaking the surface to become visible. The distance of beam 70 from the mean high water mark of the shoreline is typically in the range of 50 to 300 feet (15 to 91 m).
The frames 37 , 237 , 337 are mounted on beam 70 at an elevation where the back and forth subsurface currents are strong. This usable region typically begins one to two feet above sea floor 72 and extends to the surface and even slightly beyond.
Each of frames 37 , 237 , 337 is adjusted azimuthally so that the longitudinal axes of their linear generators 45 A- 45 F are aligned with the back and forth subsurface current of ocean water. Each frame 37 , 237 , and 337 ( FIG. 8 ) in the array 76 can be directed at different rotational angles from their neighbor. The entire apparatus is open enough to allow the free flow of ocean water in all directions. The subsurface current causes each of the six shuttles 10 located in each of frames 37 , 237 , 337 to reciprocate within their linear generators (e.g. generators 45 A- 45 F of FIG. 4 ).
Incoming waves cause the subsurface ocean currents to impinge on shuffle 10 located in coil segment 36 A ( FIG. 4 ) of linear generator 45 A (it will be appreciated that similar remarks apply to generators 45 B- 45 F). The impinging ocean current builds hydraulic pressure which urges shuttle 10 toward adjacent coil segment 36 B. The neutral buoyancy of shuttle 10 allows it to travel with its grooves 22 sliding along guide rods 24 from coil segment 36 A toward coil segment 36 B with a minimal amount of friction.
Referring to FIGS. 5 and 6 , movement of shuttle 10 causes lines of flux 54 to move relative to coil segment 36 A thereby causing a current to flow therein. The induced current flows from terminal GND through diode 68 C, conductor 64 , and coil segment 36 A. The current continues, flowing through coil segments 36 B- 36 E to conductor 66 , through diode 68 A to terminal +V. Similar current flow occurs as shuttle 10 travels through coils 36 B- 36 E in succession before shuffle 10 is stopped by end plate 49 ( FIG. 4 ) or reversed by a reversing current.
The reverse water current now impinges on the opposite end of shuttle 10 now located in coil segment 36 E (or an earlier coil segment), urging it to move toward segment 36 A. The movement of shuttle 10 causes lines of flux 54 to move relative to coil segment 36 E thereby causing a current to flow therein. The induced current flows from terminal GND through diode 68 D, conductor 66 , and coil segment 36 E. The current continues, flowing through coil segments 36 A- 36 D to conductor 64 , through diode 68 B to terminal +V. Similar current flow occurs as shuttle 10 travels through coils 36 A- 36 D before shuttle 10 is stopped by end plate 49 ( FIG. 4 ) or reversed by a reversing current.
Terminals +V and GND may be connected to a variety of electrical devices to store or condition the voltage generated by array 76 . Electrical “gas stations” near the coast can then use this energy directly to charge the plug-in electric cars of the future. Alternatively, since the electrical flow never stops, large storage batteries can be charged during periods when consumer demand is low, such as during the middle of the night. In addition, this varying flow can be directed into an electrical grid to decrease its need to burn coal, oil, natural gas, or nuclear fuel. The varying flow could also be used to power units that generate hydrogen for future cars and even power the new machines that clean the atmosphere of thousands of tons of carbon dioxide per day.
This submerged location of array 76 is out of the view of all observers, including those concerned about the despoiling of natural beauty and scenic views of the seashore. The apparatus generates no carbon dioxide byproducts, nor any other form of hydrocarbon pollution. It generates no harmful radiation. It has no moving mechanical parts beyond the primary electrical generating mechanism of the shuttles 10 floating back and forth, thereby optimizing mechanical efficiency. The machine generates electricity 24 hours per day, 7 days per week, 365 or 366 days per year.
To generate electricity, array 76 only requires waves to produce a subsurface back and forth current of ocean water. It is known that winds blowing somewhere over the ocean within 150-200 miles of array 76 cause waves that can travel to the location of array 76 without substantial loss. Since wind is almost always blowing somewhere over the ocean within 150-200 miles of array 76 it can generate electricity regardless of:
1. whether the ocean surface is substantially tranquil or is buffeted by hurricane conditions;
2. whether the tide is coming in, going out, or somewhere in between;
3. whether the sun is brightly shining or obscured by clouds; and
4. and whether the local wind is blowing or not.
“Farms” consisting of thousands of generator arrays 76 each can be politically positioned anywhere along the coasts, especially around off-shore islands, that are not utilized by the tourist industry for seashore recreation. The more violent the reciprocating flows of water around craggy rocky coasts, the more electricity is generated.
Hooking large numbers of these arrays 76 together, conceivably even thousands of them in an area of several miles of seacoast, would also effectively eliminate the fluctuations produced by any one array.
Obviously, many 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.
|
A generator can convert the energy from subsurface currents or undertow into electricity. The generator has a submergible electrical coil adapted to allow water propelled by subsurface currents to enter and flow axially through the coil. The electrical coil is supported above a sea floor in substantial alignment with the subsurface currents. A magnetic shuttle is mounted to longitudinally reciprocate in the coil, driven by water flowing through the coil. Additionally, a plurality of electrical coils can be submerged above a sea floor. Magnetic shuttles are placed separately into a corresponding one of the coils to longitudinally reciprocate, driven by water flowing through the coils.
| 5
|
BACKGROUND
[0001] The present invention relates to pipe stands, and more particularly relates to pipe stands used to support liquid-filled horizontally-extending pipes supported in a trench above ground, such as are used to convey human waste to drain fields of septic systems, though not limited to only that use.
[0002] One type of septic system (sold by Infiltrator Systems, Inc., Old Saybrook, Conn., by Chamber Systems ADS Company, and also by Hancor Company) includes waste-conveying pipes supported above ground and that extend from a septic tank to a drain field. The pipes are positioned in trenches in the ground, and supported under semi-cylindrical chambers, such as by tying the pipes to the chambers by straps or by supporting the pipes on posts that extend into the ground at a bottom of the trenches. In a gravity system, the waste-conveying pipes are generally horizontal but slightly downhill, such that the waste flows from the septic tank by gravity to a dump location in the drain field. In a low pressure system, the waste is communicated under pressure through waste pipes that define several dump locations in the drain field. Both systems require that the waste-conveying pipes be stably supported above the ground in a horizontal position so that low sections are avoided, both at installation and also over time. The avoidance of low sections prevents solid waste from collecting in low sections and thus prevents the collecting waste from stopping flow through the pipe. However, known pipe supports for the above-discussed septic system are deficient in that they require a difficult installation and also they may allow the pipe to sag and form low sections prematurely over time. For example, one system preassembles the pipe to the chambers using tie straps, and then places the pipes and chambers as a unit.
[0003] Specifically, the two most common ways of supporting waste-conveying pipes in the above-mentioned septic system include either straps or posts, both of which have significant installation and durability problems. For example, it is difficult to attach straps under the chambers and difficult to assure that the pipes are held in a horizontal position under the chambers with no low sections, since vision and reach are difficult. Further, the straps may break or sag over time (especially since waste-filled pipes are heavy), causing low sections to occur well after the installation, thus requiring maintenance and/or repair. Posts can be installed before the chambers are placed in the trench, such that installation is a bit easier than straps. However, posts tend to tip sideways or sink (or erupt from ground pressure), such that there is a significant risk of low sections forming over time. Also, sometimes it is difficult to drive the posts into the ground deep enough in the location and true-vertical orientation desired.
SUMMARY OF THE PRESENT INVENTION
[0004] In one aspect of the present invention, a pipe stand is provided for supporting a pipe above a ground surface. The pipe stand includes a flat sheet having two panels defining a fold line therebetween, the panels including a first pipe-supporting surface formed to engage and stably support a pipe and including a pipe-remote section. The sheet when folded on the fold line positions both of the pipe-supporting surfaces in an aligned position for engaging and stably supporting the pipe while simultaneously positioning the pipe-remote sections to engage the ground surface in at least three non-aligned locations for stably supporting the pipe above the ground surface.
[0005] In another aspect of the present invention, a pipe supporting system for supporting a pipe away from a primary support comprises two panels integrally connected by a living hinge. The two panels include a pipe-supporting surface formed to engage and stably support a pipe and include a pipe-remote section configured for attachment to the primary support. The sheet when folded about the living hinge positions the pipe-supporting surface in an aligned position for receiving and stably supporting the pipe while simultaneously positioning the pipe-remote sections to engage the primary support in at least three non-aligned locations for stably supporting the pipe away from the primary support.
[0006] In another aspect of the present invention, a septic system includes a drain field having a long section of waste-conveying pipe, and a plurality of pipe stands. Each stand includes at least one panel with a pipe-supporting surface and an edge adapted to stably engage a ground surface, each panel having a width extending non-parallel the pipe. By this arrangement the plurality of pipe stands can be slipped onto or under the waste-conveying pipe and the pipe stably arranged in a horizontal position without low sections before covering the waste-conveying pipe.
[0007] In another aspect of the present invention, a septic system includes an elongated chamber adapted for positioning in a trench on a ground surface. A pipe is positioned under the chamber.
[0008] Multiple pipe stands engage and support the pipe at spaced locations. The pipe stands each comprise a body having a pipe-supporting portion and include a stabilizer for the body. The stabilizer has at least three non-aligned ground-engaging points for resting on the ground surface to hold the pipe in a stable position above the ground surface based primarily on gravity.
[0009] In another aspect of the present invention, a method of constructing a septic system comprises steps of providing a trench and a long section of waste-conveying pipe, and providing a plurality of pipe stands, each including at least one panel with a pipe-supporting surface and an edge adapted to stably engage a ground surface. The method further includes positioning the pipe stands transversely to the pipe and in a position supporting the pipe, including slipping the pipe stands onto or under the waste-conveying pipe before covering the waste-conveying pipe.
[0010] In a broader aspect of the present invention, it is contemplated that the present pipe stand includes a structural member of sufficient strength to support a pipe in an elevated position, and includes a pipe-receiving feature and a ground-engaging stabilizer of sufficient width to prevent tip-over.
[0011] An object of the present invention is to provide a very simple pipe stand that is durable, long-lasting, and very stable when used to support waste-conveying pipes in the primary environment of a septic system.
[0012] An object of the present invention is to provide a pipe stand that promotes an efficient installation of a septic system, and which is intuitive to use, yet flexible in use.
[0013] These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0014] FIG. 1 is a perspective view of a septic system including the drain field, the drain field being uncovered so that components can be seen, one of the chambers being broken away to reveal the waste-conveying pipe as supported by a pipe support of the present invention.
[0015] FIG. 2 is a cross section taken through a chamber in the drain field, showing the chamber, the pipe, and the pipe stand, and FIG. 3 is a perspective view showing a similar area and components.
[0016] FIG. 4 is a perspective view of a long waste-conveying pipe section and with multiple pipe stands for supporting the pipe.
[0017] FIGS. 5-6 are plan and side views of a pipe stand blank prior to bending.
[0018] FIGS. 7-20 are perspective views of alternative pipe stand constructions, FIGS. 13 and 20 showing installations.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0019] The present pipe stands 20 ( FIGS. 1-4 ) support waste-conveying pipes 21 above a trench-bottom ground surface 22 in a septic system 23 having a septic tank 19 . The illustrated septic system 23 includes semi-cylindrically-shaped chambers 24 that are positioned over the pipes 21 in the drain field 25 thereby defined. Notably, FIG. 1 illustrates the components 20 , 21 , and 24 as positioned in a bottom of trenches 26 . These trenches 26 are filled during a later part of the installation to a level generally equal to the top soil 27 , with the chambers 24 protecting the pipes 21 (and stands 20 ).
[0020] The present pipe stands 20 are particularly simple, effective, flexible in use, and easy to install in the present environment of a septic system for a variety of reasons. In regard to their construction, the pipe stand 20 ( FIGS. 4-6 ) is cut from a flat bowtie-shaped sheet (preferably durable polymeric sheet such as high density polyethylene that is about ⅛″ to ¼″ thick, though it could be metal, aluminum, composite, or other structural material). The bowtie shape defines two panels 30 and 31 connected by a narrow region 32 (also called a “fold line” or a “living hinge”). The narrow region 32 of the “bow tie” shape, when folded, forms a living hinge that biases the panels 30 and 31 toward a more planar shape. The fold line can include slits or thinned areas to assist in folding, and to reduce the outward biasing force. This may be desirable when it is unnecessary for the panels 30 and 31 to frictionally engage the pipe 21 . A hole 33 is formed in each panel slight larger than the pipe 21 that it is intended to receive, thus forming a pipe-supporting surface. The holes 33 align when the sheet is folded, thus providing a stable two-point support for a horizontal pipe 21 . In stands where the panels 30 and 31 are biased apart, the stand 20 frictionally engages the pipe 21 . This assists in installation by holding the stands in position on the pipe 21 while the pipe 21 is being manipulated to a final position. Advantageously, the pipe 21 does not have to be tied to the chamber 24 covering it.
[0021] Also, when attached to the pipe 21 , each bottom edge 35 and 36 of the panels 30 and 31 rest on the ground. Due to a width of the edges 35 and 36 , they stably engage the ground surface 22 even if there are some variations in the surface 22 . A fold-out foot 37 is formed at the bottom edges 35 and 36 by pairs of slots 38 . The fold-out foot 37 is useful where the ground is soft, since it can be bent to a horizontal position that gives a wider footprint along the bottom edge 35 and 36 . At the same time, the end tabs 39 (outboard of the foot 37 ) extend into the soil of the ground surface 22 , adding further stability to the arrangement.
[0022] It is noted that variations can be made in the pipe stand 20 of FIG. 5-6 . For example, pipe stand 20 can be used in a second orientation (i.e. rotated about 100 degrees on the pipe from the orientation shown in FIG. 2-3 ). In this second orientation, the pipe 21 is positioned slightly closer to the ground surface 22 , thus giving the user a height selection capability. Also, the living hinge can be replaced with actual hinges or straps or tethers. Further, the material of the stand 20 can be any structural material, including metal (corrosion-treated steel, stainless steel, aluminum) composites, and other materials. The pipe stand 20 can be injection molded, stamped, CNC cut, saw and drilled, die-cut, water-jet cut, routed, or shaped by other known methods.
[0023] A number of modified pipe stands are shown in FIGS. 7-20 . In these modified pipe stands, similar and identical components, features and characteristics are identified using identical numbers to those used in FIGS. 1-6 , but with the addition of a letter “A,” “B,” “C,” etc. This is done to reduce redundant discussion. Notably, the various modified pipe stands include the same features and characteristics as the pipe stand 20 unless otherwise noted.
[0024] The pipe stand 20 A ( FIG. 7 ) is similar to pipe stand 20 except pipe stand 20 A includes slots 40 A at ends of the fold line 32 A. This reduces an outward bias of the living hinge, thus making it easier to fold the sheet to form the pipe stand 20 A and also reducing a grip of the pipe stand 20 A on the pipe ( 21 ).
[0025] The pipe stand 20 B ( FIG. 8 ) includes a hole 33 B and further includes a plurality of circular slits or depressions forming a plurality of punch-out rings 41 B- 43 B of different sizes around the hole 33 B. Each ring 41 B- 43 B can be punched out to form a hole sized for a particular pipe ( 21 ), such as 1¼″, 1½″, 2″, 3″, etc.
[0026] The pipe stand 20 C ( FIG. 9 ) includes a notch 33 C instead of a hole ( 33 ). The notch 33 C opens toward the fold line 32 C, thus reducing a strength of the living hinge at the fold line 32 C. Also, there are slits 44 C at outer ends of the fold line 32 C, further weakening the bias of the living hinge. Notably, the edges of the notch 33 C extend vertically, such that it engages a maximum of 180 degrees of the pipe ( 21 ). Note that pipe stands 20 D ( FIG. 10) and 20E ( FIG. 11 ) include inwardly-facing tips 45 D (rounded) and 45 E (relatively pointed) at upper ends of their respective notches 33 D and 33 E. The tips 45 D, 45 E are made to resilient snappingly engage a pipe 21 D, 21 E pressed into the respective notch 33 D or 33 E. Thus, the pipe 21 D, 21 E is retained in the notch ( 33 D, 33 E) even though the notch 33 D, 33 E is upwardly open.
[0027] The pipe stand 20 F ( FIGS. 12-13 ) includes slots 40 F at ends of its fold line 32 F (similar to pipe stands 20 A), which shorten its living hinge and the bias of its hinge. Slots 38 F are formed to define a fold-out foot 37 F. The illustrated end tabs 39 F are pointed and stake-simulating, such that they dig into soft ground for retaining the panels 30 F and 31 F in position. Further, the tabs 39 F include a small hole or other feature/structure 47 F for receiving a U-shaped ground-engaging wire stake or pin 48 F that fixedly holds the panels 30 F and 31 F in their respective selected positions.
[0028] A U-shaped slot 49 F ( FIGS. 12-13 ) is formed in the panels 30 F and 31 F, defining a fold-out dispersing flange 50 F. In pressurized septic systems, the waste product 51 F is pushed out openings 52 F in the pipe 21 F. When the waste product 51 F is dispensed onto a dispersing flange 50 F, the flange 50 F spreads the waste product 51 F and reduces an impact of the waste product 51 F as it engages a particular area of the ground 22 F.
[0029] The pipe stand 20 G ( FIG. 14 ) includes three holes 33 G, 53 G, and 54 G, each sized to receive a different size diameter pipe ( 21 ). Each hole 33 G, 53 G, and 54 G is located in a different corner of the pipe stand 20 G. By positioning the pipe stand 20 G in different orientations (compare FIGS. 14 and 15 ), different holes 33 G, 53 G, 54 G can be positioned at a top of the stand 20 G (i.e., at their preferred height). It is contemplated that more or less holes 33 G, 53 G, 54 G could be used, and also that punch-out rings could be used in combination with multiple holes 33 G, 53 G, 54 G. Also, it is noted that the living hinge of pipe stand 20 G is located at a corner and that the panels 30 G and 31 G are triangularly shaped, such that the living hinge is relatively short without the need for cutting slots into the fold line 32 G.
[0030] The pipe stand 20 H ( FIG. 16 ) includes a stabilizer panel 56 H with corners having tabs 57 H configured to frictionally engage the end tabs 39 H. When engaged, the stabilizer panel 56 H holds the panels 30 H and 31 H at a desired spacing, thus adding stability to the pipe stand 20 H without the need for stability to come from the way that the holes 33 engage the pipe ( 21 ). Also, the stabilizer panel 56 H adds considerably to the footprint of the pipe stand 20 H, and can be particularly useful where the soil is particularly soft. Nonetheless, it is noted that care must be taken to not reduce the surface area of the ground surface, since a minimum amount of surface area is required in order to qualify as a drain field for a given septic system.
[0031] The pipe stand 20 I ( FIG. 17 ) includes two triangular panels 30 I and 31 I connected by a relatively long fold line 32 I. As noted above, the fold line 32 I can be made easier to fold if necessary, such as by adding perforations, slits, slots, or thinned areas along the fold line 32 I. As illustrated, the holes 33 I are located near the outer corners of the triangular panels 30 I and 31 I. When folded, the long fold line 32 I is positioned at the ground, with the pipe 21 I engaging the holes 33 I at a selected height above the ground and fold line 32 I. Notably, in previous illustrated pipe stands, the fold line was along a top (or side) of the part. In pipe stand 20 I, it is located along its bottom.
[0032] The pipe stand 20 J ( FIG. 18 ) includes a panel-shaped structural member 30 J of sufficient strength to support a pipe 21 J in an elevated position above a ground surface 22 J, and includes a pipe receiving feature (hole 33 J and potentially within the hole 33 J a short pipe 33 J° large enough to receive pipe 21 J) and a ground-engaging stabilizer (foot 37 J) of sufficient width to prevent tip-over. The foot 37 J can be integrally formed as part of the structural member 30 J (and folded outwardly therefrom), or can be a separately formed part attached along a bottom edge of the panel-shaped structural member 30 J.
[0033] The pipe stand 20 K ( FIG. 19 ) includes a pair of panel-shaped structural members 30 K and 31 K connected by transverse rib 32 K from their bottom and connected by pipe 21 K at their top, where the pipe 21 K is extended through closely fitting holes 33 K.
[0034] The pipe stand 20 L ( FIG. 20 ) is similar to pipe stand 20 , and includes two panels 30 L and 31 L connected at their narrow section (fold line 32 L). The pipe 21 L is extended through holes 33 L. However, the pipe stand 20 L is inverted so that panels 30 K and 31 K can be attached to an overhead beam, such as a ceiling beam or floor joist 60 K. Thus, the present pipe stand is converted into a pipe hanger. This same concept of inverting the component and using it as a hanger can be done using any of the pipe stands shown in FIGS. 6-8 , 10 - 12 , 18 - 19 .
[0035] Advantageously, the present pipe stands can be used in low pressure chamber systems, and do not have to be tied to a chamber. This allows the chamber to be installed after the “squirt” test. The present stands are easily installed, including folding and sliding onto the pipe that they support. They ship flat and are low weight, such that they ship at low cost, and are easily shipped and stored. They are easily adjustable to different spacings on a given pipe. Notably, different pipe sizes require different spacings, and the present pipe stands readily fill that need, while providing excellent stability and levelness of the pipe off the ground. In some forms, the pipe stands squeeze the pipe, yet release for adjustment. Some pipe stands cradle and/or snap over the pipe for additional sureness of retention. Others have punch-outs that permit selection of a desired hole size. The present pipe stands are independent from the chamber, and stand alone. They fit multiple sizes of pipes, with holes on one pipe stand fitting more than just one pipe size. Sides of the pipe stands can be fixed in a desired spread condition, either by using a cross piece, or ground-engaging tabs. Further, the sides of the pipe stands can include fold-out feet for increased footprint for loose soil, and also can include fold-out flanges for dispersing waste material dropping from the pipe. The pipe stands include integral hinges that are low-cost, easily bent to a desired shape, and ARE highly efficient and satisfactory for their intended purpose. The pipe stands can be inverted and used as a pipe hanger. They can be made by a variety of processes, such as injection molding, stamping, cutting, forming, sawing/drilling, and the like. They can be made out of many different materials, such as plastic, metal (steel, aluminum) composite, or the like. The present pipe stands can be made to virtually any size or shape, with any desired hole size.
[0036] It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.
|
Pipe stands support waste-conveying pipes in a trench in a septic system. The pipe stands are preferably flat bowtie-shaped sheets (preferably polymeric). Holes or notches are formed that align when the sheet is folded, thus providing stable support for a horizontal pipe when the panels' bottom edges rest on the ground. Modified versions include panels having: a fold-out foot for engaging soft soil, a fold-out dispersing flange for dispersing waste dropped from the pipe, a stake for driving into soft soil, punch-out rings or multiple holes for supporting different sized pipes, stabilizers between the panels that fixedly maintain their spacing, a feature for receiving a grounded wire stake, and/or bias from the living hinge of the fold line causing frictional gripping of the pipe. Many versions can be used in different orientations. Also, the present pipe stand can be used to support pipes and wires hanging from overhead rafters.
| 4
|
This application is a division of application Ser. No. 09/639,938, filed Aug. 17, 2000, now U.S. Pat. No. 6,599,874, which is a Division of application Ser. No. 08/793,047, filed Jul. 24, 1997, now abandoned, which is a 371 of PCT/SE94/00742, filed Aug. 16, 1994.
DESCRIPTION
Technical Field
The present invention relates to a novel antibacterial protein and compositions, in the form of pharmaceutical compositions, human food compositions, and animal feedstuffs comprising said protein to be used in the therapeutic and/or prophylactic treatment of infections caused by bacteria, in particular Streptococcus pneumoniae and/or Haemophilus influenzae as well as a method for diagnosing infections caused by said bacteria.
The object of the present invention is to obtain a protein and compositions containing said protein for prophylactic and/or therapeutic treatment of infections caused by bacteria, in particular Streptococcus pneumoniae and Haemophilus influenzae in the upper airways, ear-nose-and-throat infections, but also in the lower airways, e.g., the lungs by preventing adhesion of and/or causing a bactericidal effect on these bacteria. A further object is to be able to diagnose infections caused by these bacteria.
BACKGROUND OF THE INVENTION
Natural antimicrobial compounds exist in secreted form as well as in cells of immune and non-immune origin.
Human milk has been used as a source for the purification of such compounds. These previously known compounds include specific antibodies to the micro-organism surface structure, casein, lysozyme, and oligosaccharides. The mechanism of action differs between the groups of antimicrobial molecules. Antibodies and receptor analogues prevent micro-organism adherence to mucosal surfaces. Lysozyme attacks the cell wall etc.
The term bacterial adherence denotes the binding of bacteria to mucosal surfaces. This mechanic association is a means for the organism to resist elimination by the body fluids, and to establish a population at the site where relevant receptors are expressed. In most cases where the mechanisms of attachment have been identified it is a specific process. The bacterial ligands, commonly called adhesins bind to host receptors. For Gram-negative bacteria, the adhesins are commonly associated with pili or fimbriae, rigid surface organelles that help bacteria to reach the appropriate receptor in the complex cell surface. The fimbriae function as lectins, i.e. they show specificity for receptor epitopes provided by the oligosaccharide sequences in host glyco-conjugates (13). For Gram-positive bacteria, on the other hand, the adhesins are not expressed as a surface organell, but rather linked to cell wall components and lipoteichoic acids (21, 22). The receptor epitopes for Gram positive bacteria may consist of oligosaccharide sequences but can also be provided by peptides e.g. in connective tissue proteins (10).
The functional consequences of adherence depend on the virulence of the bacterial strain, and on the form of the receptor. When cell-associated, the ligand receptor interaction facilitates colonization and tissue attack (8). When secreted the receptor molecule will occupy the adhesins, and competitively inhibit attachment to the corresponding cell-bound receptor. Human milk is a rich source of such competing soluble receptor molecules.
The ability of specific antibodies to inhibit attachment is well established. This was first demonstrated for Vibrio cholera and oral streptococci. The anti-adhesive antibodies may act in either of two ways:
1) Antibodies to the receptor binding sites of the adhesin competitively inhibit receptor interaction or
2) antibodies to bacterial surface molecules which are not directly involved in adherence may agglutinate the bacteria and thereby reduce the number of organisms available for binding.
In either of the above cases the anti-adhesive activity of the antibody is attributed to the specificity of the antigen-combining site. Recently an alternative mechanism of interaction between secretory IgA and E. coli based on lectin-carbohydrate interactions was identified.
Human milk drastically inhibits the attachment of Streptococcus pneumoniae and Haemophilus influenzae to human nasopharyngeal epithelial cells. It contains antibodies to numerous surface antigens on these organisms. e.g., the phosphoryl choline and capsular polysaccharides of S. pneumoniae , the lipopolysaccharide and outer membrane proteins of H. influenzae . Accordingly, some of the anti-adhesive activity in milk resides in the immunoglobulin fraction.
The remaining anti-adhesive activity in the non-immunoglobulin is fraction of milk may be explained by two types of molecules: free oligosaccharides and glycoproteins in the casein fraction.
Human milk is unique with regard to its content of complex carbohydrates. The free oligosaccharide fraction of milk is dominated by the lactoseries and with improving methods of isolation and characterization of carbohydrates more than 130 oligosaccharides containing up to 20 monosaccharides per molecule have been identified.
An anti-adhesive activity against S. pneumoniae in a low molecular weight fraction (<5 kDa) of milk was explained by the free oligosaccharides. In contrast there was no such effect against H. influenzae (15).
An anti-adhesive activity of high molecular weight components of milk was localized to the casein fraction. Human casein drastically reduced the adherence both of S. pneumoniae and H. influenzae (15). This effect was species specific.
Alpha-lactalbumin is a mettaloprotein, which shows some degree of heterogeneity depending on Ca(II) saturation and/or glycosylation (1). Alpha-lactalbumin acts as a specifier protein in the lactose synthase system. During lactation, alpha-lactalbumin is formed in the mammary gland and it alters the substrate specificity of the galactosyltransferase enzyme from N-acetyl glucosamine (GlcNAc) to glucose (Glc), enabling lactose synthesis to take place:
Multiple forms of bovine, pig, sheep and goat alpha-lactalbumin have been isolated and well characterized (2, 3). These multiple forms differ in a few amino residues or the number of disulphide bonds (4, 5) but are all active in the lactose synthase system. The physiological relevance or functions of these different forms of alpha-lactalbumin are not known. Alpha-lactalbumin has undergone a high rate of evolutionary change and it shows homology with lysozyme (1). These two proteins are thought to originate from the same ancestral protein. Whereas lysozyme is known as an anti-bacterial agent, alpha-lactalbumin has not yet been found to have antibacterial functions.
SUMMARY OF THE INVENTION
The present invention describes the identification of a new anti-bacterial protein or group of proteins from milk. The protein comprises a multimeric form of alpha-lactalbumin.
In the following this protein, or group of proteins, is abbreviated ALLP, Anti-adhesive. Lactalbumin Like Protein.
The term antimicrobial or anti-bacterial protein used in the context of the present invention means here and in the following a protein which inhibits adherence of micro-organisms to tissue and/or exerts a bactericidal effect an microorganisms.
Further characteristics of the invention will be evident from the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 . The ion-exchange fractionation profile of casein ( FIG. 1A ) and commercial human alpha-lactalbumin ( FIG. 1B ). The arrow represents the time point at which 1 M NaCl was applied.
FIG. 2 . Gel chromatographic fractionation profiles of pool VI obtained from fractionation of case in ( FIG. 2A ) and human alpha-lactalbumin before ion-exchange chromatography ( FIG. 2B ).
FIG. 3 . Ion-exchange fractionation profile of pool LA 2 obtained after ion-exchange chromatography of alpha-lactalbumin.
FIG. 4 . Mass spectrometry of ALLP.
DETAILED DESCRIPTION OF THE INVENTION.
The present invention will be described more in detail with reference to the example given below.
Experimental
Purification of the Active Anti-Adhesive and Bactericidal Protein (ALLP)
Milk samples from lactating women were screened for anti-adhesive activity against S. pneumoniae and H. influenzae . About 50 l of breast milk with high anti-adhesive activity was collected from one healthy donor and used for the purification of ALLP. About 5 l of milk was thawed at a time and centrifuged to remove fat. Casein was prepared from the defatted milk by acid precipitation at pH 4.6. ALLP was purified as outlined below:
(i) Ion-Exchange Chromatography of Casein.
Casein was fractionated using an ion-exchange column (14 cm×1.5 cm) packed with DEAE-Tris-acryl M (LKB, Sweden) attached to an FPLC (Pharmacia, Sweden) using a NaCl gradient: 100 mg of the lyophilized casein was dissolved in 10 ml of 0.01 M Tris-HCl, pH 8.5. After centrifugation, the sample was directly applied to the column and the run was under the following conditions: buffer A: 0.01 M Tris-HCl, pH 8.5; Buffer B: buffer A containing 1 M NaCl/l. Gradient program: from 0–3 ml 100% A, from 3–60 ml 15% B; from 60–85 ml 25% B; from 85–87 ml 100% B; from 87–89 ml 100% B for 2 min; from 89–120 ml 100% A. The gradient was not linear, but was interrupted at the elution of each peak for better separation. Flow rate: 1 ml/min, recorder 0.2 cm/min. The buffers were degassed and filtered through a 0.22 um filter before use. The peaks were monitored at 280 nm and the fraction size was 3 ml. Fractions were pooled as shown ( FIG. 1A ). The pools (I–VI) were then desalted by dialysis (membrane cut off 3.5 kD) against distilled water for at least 48 hrs, lyophilized and tested for anti-adhesive activity.
(ii) Gel Chromatography of Pool VI
100 mg of the active pool VI obtained after repeated FPLC fractionations of casein, were dissolved in 7 ml 0.06 M sodium phosphate buffer, pH 7.0 and applied to a Sephadex R G-50 (Pharmacia, Sweden) column (93 cm×2.5 cm). Flow rate was 30 ml/hr, peaks were monitored at 280 nm, 3 ml fractions were collected and pooled as shown ( FIG. 2A ). The pools were desalted by dialysis, lyophilized, tested for composition and for anti-adhesive activity.
Ion-exchange chromatography of commercial alpha-lactalbumin. 20 mg of commercial (Sigma) human or bovine alpha-lactalbumin were dissolved in 2 ml 0.01 M Tris-HCl, pH 8.5. The ion-exchange chromatography of alpha-lactalbumin was under similar conditions as described above for the fractionation of casein. The NaCl gradient was linear (not interrupted), flow rate was 1 ml/min, 3 ml fractions were collected and pooled as shown in FIG. 1B . The pools were dialysed. (membrane cut-off 3.5 kD), lyophilized, resuspended to the required concentration and tested for anti-adhesive activity.
Gel Chromatography of Commercial Alpha-Lactalbumin
Approximately 8–10 mg of commercial human or bovine alpha-lactalbumin (Sigma) were dissolved in 3 ml 0.06 M sodium phosphate buffer, pH 7.0 and fractionated on the Sephadex R G-50 column as described above. Flow rate was 30 ml/hr, peaks were monitored at 280 nm, 3 ml fractions were collected and pooled as shown ( FIG. 2B ). The pools were desalted by dialysis (membrane cut-off 3.5 kD) against distilled water for at least, 48 hrs, lyophilized, tested for composition and for anti-adhesive activity. 6–8 mg retained of the material retained and eluting after 1 M NaCl during ion-exchange chromatography of alpha-lactalbumin were dissolved in 5 ml 0.06 M sodium phosphate buffer pH 70 and subjected to gel chromatography on the G-50 column as described above. 3 ml fractions were collected and pooled ( FIG. 3 ). The pools were desalted, lyophilized, and tested for anti-adhesive activity.
Polyacrylamide Gradient Gel Electrophoresis (PAGGE).
Analytical PAGGE was performed using 4–20%-polyacrylamide pre-cast gels (Bio-Rad, Richmond, Calif.) on a Bio-Rad Mini Protean II cell. To 10/ul (5–10 mg/ml) each of the lyophilized fractions, an equal volume of sample buffer (13.1% 0.5 M Tris-HCl, pH 6.8, 10.5% glycerol, 1.2% SDS and 0.05% bromophenol blue) was added. 20/ul of each was then loaded on to the gel which was run in Tris-glycine buffer (pH 83) with 0.1% SDS at 200V constant voltage for about 40 min. Staining of the proteins was made by immersing the gel in Coomassie Blue solution (0.1% in 40% methanol; 10% acetic acid) for about 0.5 hr. Destaining was by several changes ire 40% methanol, 10% acetic acid until a clear background was obtained.
Ion Desorption Mass Spectrometry
ALLP and commercial alpha-lactalbumin were analyzed by ion-desorption mass spectrometry.
Bacteria
S. pneumoniae (CCUG3114 and 10175) and H. influenzae (Hi198) were used throughout the experiments. These strains were known to adhere well to human nasopharyngal epithelial cells in vitro. These strains were initially isolated from the nasopharynx of children with frequent episodes of acute otitis media. The strains were kept lyophilized and were transferred to blood agar (10175) or Levinthal medium agar plates (Hi 198) S. pneumoniae was cultured for 9 hrs at 37° C. in liquid medium (17), harvested by centrifugation and suspended in 1 ml of 0.9% NaCl with 1% choline H. influenzae Hi198 was cultured for 4 hrs in haemophilus medium (18), harvested by centrifugation and suspended in phosphate-buffer saline, (PBS).
Adhesion Inhibition
Adhesion and inhibition of adhesion was tested as previously described (15, 19). In brief, epithelial cells from the oropharynx of healthy donors ( 10 5 /ml) were mixed with the bacterial suspensions (10 9 /ml). After incubation of bacteria and epithelial cells, unbound bacteria were eliminated by repeated cycles of centrifugation and resuspension in NaCl with 1% choline (10175) or PES (Hi 198).
The inhibitory activity of the different fractions was tested by preincubation with bacteria for, 30 min at 37° C. prior to addition of epithelial cells. The number of epithelial cells attached was counted with the aid of an interference contrast microscope (Ortolux II microscope with interference contrast equipment TE Leitz, Wetzlar). Adherence was given as the mean number of bacteria/cell for 40 epithelial cells. Inhibition was given in percent of the value of the buffer control.
Results
Properties of ALLP
ALLP was purified from human milk by fractionation of casein by ion-exchange chromatography and fractionantion of the pool eluting after 1 M NaCl by gel chromatography. The ion-exchange fractionation profile of casein is shown in FIG. 1A . Eluted fractions were pooled as indicated and tested for anti-adhesive activity. Pool VI retained the anti-adhesive activity of casein; this pool inhibited the attachment of S. pneumoniae and H. influenzae by more than 80% of the control (Table 3). The remaining fractions were inactive and were not analyzed further.
Pool VI was fractionated by gel chromatography on the Sephadex R G-50 column. The fractionation profile showed two distinct well separated peaks ( FIG. 2A ). Eluted fractions were pooled as shown, desalted, and tested for anti-adhesive activity. Pool K retained 98% of the anti-adhesive activity against S. pneumoniae and 91% of the activity against H. influenzae . Pool L was inactive (Table 3).
Analytical PAGGE of pool K showed the presence of bands in the 14–15 kD region, one band in the 30 kD region, and two bands stained in the 100 kD region. Pool L showed the presence of only one band in the 14–15 kD region ( FIG. 2A , inset). The N-terminal amino acid sequence analysis showed that the bands of pool K were similar and were identical to the N-terminal sequence of human alpha-lactalbumin. The active anti-adhesive protein in pool K was designated as Anti-adhesive Lactalbumin Like Protein (ALLP). ALLP reduced attachment of both S. pneumoniae and H. influenzae by about 60% at a concentration of 1 mg/ml
Mass Spectrometry of ALLP
The results from analytical PAGGE suggested that ALLP might occur in a multimeric form. By ion laser desorption mass spectrometry. ALLP showed three distinct mass fragments (1, 2 and 3) at 14128.7 m/z, 28470.5 m/z and 42787.8 m/z, respectively ( FIG. 4 ). These fragments agreed with the monomeric (14 m/z), dimeric (28 m/z) and trimeric (42 m/z) mass ranges of the protein.
Comparison of ALLP and Commercial Alpha-Lactalbumin
When tested for anti-adhesive activity, commercial alpha-lactalbumin did not inhibit the adherence of S. pneumoniae or H. influenzae even at a concentration of 10 mg/ml (Table 4). ALLP showed stained bands in the 14–15 kD, 30 kD and the 100 kD regions, whereas the commercial alpha-lactalbumin stained only one band in the 14–15 kD region. The N-terminal amino acid sequence of ALLP showed complete homology with the sequence of human alpha-lactalbumin.
The lack of anti-adhesive activity of commercial alpha-lactalbumin, as compared to ALLP, might be due to a difference in their molecular forms. Therefore commercial human aloha-lactalbumin was subjected to ion laser desorption mass spectrometry. The spectrum showed only one mass fragment at 14128.7 m/z corresponding to the monomeric form of alpha-lactalbumin (calculated molecular mass=14.079 kD). Thus commercial human alpha-lactalbumin was in the monomeric form and lacked anti-adhesive activity, whereas, ALLP was found to be multimeric and inhibited the attachment of S. pneumoniae and H. influenzae to human oropharyngeal cells in vitro.
Ion-Exchange Chromatography of Human Alpha-Lactalbumin
In order to test the effect of ion exchange chromatography on the anti-adhesive effect of commercial human alpha-lactalbumin, 20 mg of the commercial sample was applied onto the Tris-acryl column. The ion-exchange profile is shown in FIG. 1B . About 50% of the material applied was retained on the column and eluted after the application of 1 M NaCl (arrow, FIG. 1B ). The different fractions were pooled as shown. After desalting and lyophilization the fractions were reconstituted to a concentration of about 5–10 mg/ml and tested for anti-adhesive activity.
Anti-Adhesive Effect of Human Alpha-Lactalbumin after Ion-Exchange Chromatography
Before ion-exchange chromatography commercial human alpha-lactalbumin lacked anti-adhesive activity (Table 4). After it was subjected to ion-exchange chromatography, the pool which was retained and eluted with 1 M NaCl (pool LA 2 , FIG. 1B ) inhibited the attachment of both S. pneumoniae and H. influenzae by more than 95% of the value of the control (Table 4). The other pool (LA 1 ) obtained was inactive.
Gel Chromatography of Human Alpha-Lactalbumin before and after Ion-Exchange Chromatography
Since about 50% of the commercial human alpha-lactalbumin had become active after ion-exchange chromatography it was decided to check the mobility of the alpha-lactalbumin and pool LA 2 on gel chromatography.
The G-50 gel chromatographic profile of human alpha-lactalbumin before ion-exchange chromatography is shown in FIG. 2B . The alpha-lactalbumin eluted as a single peak, which gave a single band (14–15 kD) on PAGGE analysis (inset, FIG. 2B ). This pool LA was found to be inactive when tested for anti-adhesive activity (Table 4).
The gel chromatographic profile of the active pool LA 2 , obtained after ion-exchange chromatography of alpha-lactalbumin is shown in FIG. 3 . This pool eluted as two well separated peaks (1 and 2, FIG. 3 ) corresponding to the eluting volumes of peaks K and L of the casein ( FIG. 2A ). When tested for anti-adhesive activity pool 1 retained the activity against both S. pneumoniae and H. influenzae , whereas pool 2 was inactive (Table 4).
When pool 1 was analysed by analytical PAGGE a pattern similar to that of ALLP was obtained, bands stained at 14–15 kD region, 30 kD region, and two bands at 100 kD region. Pool 2 gave a single band at the 14–15 kD region, corresponding to monomeric alpha-lactalbumin (inset, FIG. 3 ).
Properties of Commercial Bovine Alpha-Lactalbumin.
Since commercial human alpha-lactalbumin could be converted to the active multimeric form by ion-exchange chromatography it was decided to test the activity of bovine alpha-lactalbumin and to test its mobility on ion-exchange and gel chromatography. When tested for anti-adhesive activity, bovine alpha-lactalbumin was found to be inactive in inhibiting the attachment of S. pneumoniae and H. influenzae (Table 5).
20 mg of bovine alpha-lactalbumin were subjected to ion-exchange chromatography under similar conditions described above for human alpha-lactalbumin. 50% of the material applied to the column was retained and eluted after 1 M NaCl. The elution pattern was similar to that obtained for human alpha-lactalbumin ( FIG. 1B ). Pool BL 2 of bovine alpha-lactalbumin, corresponding to the elution volume of pool LA 2 of human alpha-lactalbumin ( FIG. 1B ) inhibited the attachment of S. pneumoniae by more than 95% and of H. influenzae by more than 80% of the value of the control (Table 5).
When subjected to gel chromatography on the G-50 column as described above, bovine alpha-lactalbumin eluted as a single peak corresponding to the elution volume of human alpha-lactalbumin ( FIG. 2B ). In contrast, the material in pool BL 2 resolved into two distinct peaks corresponding to pools 1 and 2 obtained for human alpha-lactalbumin ( FIG. 3 ). The pool eluting just after the void volume of the column (corresponding to pool 1) retained the anti-adhesive activity, whereas, the other pool was inactive. The active pool had a PAGGE pattern similar to that of ALLP, whereas, the inactive pool stained only one band in the 14–15 kD region.
Thus a portion of the commercial bovine alpha-lactalbumin was also converted to the active multimeric form by ion-exchange chromatography.
Bactericidal Effect
The present ALLP was tested with regard to bactericidal effect on different strains of S. pneumoniae being known to be resistant to antibiotics, and some other strains of Streptococcus, E. coli, H. influenzae and M. cath.
Thereby the different bacterial strains were inoculated onto growth plates after incubation with ALLP in different concentrations. The viable counts (CFU) were determined at inoculation, 0.5 h, 2 h, and 4 h (hours), respectively after inoculation. Table 1 below shows the viable counts after incubation to a medium containing 10 mg/ml of ALLP compared with the control.
TABLE 1
Viable counts (CFU) on S. pneumoniae strains
after exposure to ALLP.
Strain
Viable counts (CFU)
designation
0 h
0.5 h
2 h
4 h
10175
control
2 × 10 6
1 × 10 6
1 × 10 5
1 × 10 4
ALLP
2 × 10 5
—
—
—
15006-92
control
1 × 10 4
2 × 10 4
1 × 10 3
—
ALLP
2 × 10 4
—
—
—
14060-92
control
2 × 10 6
1 × 10 5
1 × 10 4
—
ALLP
2 × 10 5
—
—
—
15256-92
control
1 × 10 6
2 × 10 6
2 × 10 5
4 × 10 4
ALLP
2 × 10 6
—
—
—
14326-92
control
4 × 10 5
2 × 10 5
2 × 10 4
2 × 10 3
ALLP
7 × 10 4
—
—
—
Prag 1828
control
5 × 10 6
2 × 10 6
5 × 10 5
—
ALLP
5 × 10 6
—
—
—
14091-92
control
3 × 10 5
5 × 10 5
1 × 10 5
—
ALLP
7 × 10 5
—
—
—
14117-92
control
2 × 10 6
2 × 10 6
2 × 10 6
—
ALLP
2 × 10 6
—
—
—
14612-92
control
3 × 10 5
1 × 10 5
2 × 10 4
1 × 10 3
ALLP
3 × 10 4
—
—
—
Dk 84/87
control
1 × 10 7
5 × 10 6
2 × 10 6
6 × 10 4
ALLP
3 × 10 5
—
—
—
14007-92
control
1 × 10 5
5 × 10 4
4 × 10 3
—
ALLP
1 × 10 5
—
—
—
14030-92
control
5 × 10 6
2 × 10 6
2 × 10 5
—
ALLP
5 × 10 6
2 × 10 1
—
—
14423-92
control
6 × 10 5
6 × 10 6
1 × 10 6
6 × 10 5
ALLP
2 × 10 5
3 × 10 1
—
—
4502-93
control
4 × 10 5
—
—
—
ALLP
5 × 10 4
—
—
—
SA44165
control
2 × 10 5
5 × 10 3
—
—
ALLP
3 × 10 5
—
—
—
1017-92
control
1 × 10 6
5 × 10 5
4 × 10 3
—
ALLP
9 × 10 5
—
—.
—
317-93
control
4 × 10 4
1 × 10 4
5 × 10 3
—
ALLP
2 × 10 3
—
—
—
760-92
control
2 × 10 7
2 × 10 6
1 × 10 4
1 × 10 4
ALLP
8 × 10 6
—
—
—
Hun 859
control
6 × 10 5
3 × 10 5
2 × 10 5
2 × 10 5
ALLP
3 × 10 5
—
—
—
Hun 963
control
1 × 10 7
4 × 10 6
1 × 10 5
—
ALLP
5 × 10 6
—
—
—
BN 241
control
4 × 10 6
5 × 10 4
2 × 10 4
—
ALLP
2 × 10 5
—
—
—
TABLE 2
Viable counts (CFU) on different bacterial species
Strain
Viable counts (CFU)
designation
0 h
0.5 h
2 h
4 h
S. mitis
control
1 × 10 6
10 × 10 6
2 × 10 5
1 × 10 5
116
ALLP
1 × 10 6
—
—
—
S. sanguis
control
5 × 10 7
3 × 10 7
4 × 10 7
5 × 10 6
197
ALLP
3 × 10 7
2 × 10 5
2 × 10 2
—
E. coli
control
6 × 10 6
5 × 10 6
3 × 10 6
3 × 10 6
60
ALLP
7 × 10 6
5 × 10 6
1 × 10 7
2 × 10 7
4
control
5 × 10 6
5 × 10 6
5 × 10 6
7 × 10 6
ALLP
5 × 10 6
6 × 10 6
1 × 10 7
2 × 10 7
H. influenzae
control
4 × 10 7
1 × 10 7
4 × 10 6
2 × 10 5
21594
ALLP
3 × 10 7
4 × 10 5
<1 × 10 3
<1 × 10 3
21300
control
4 × 10 7
2 × 10 7
5 × 10 6
3 × 10 5
ALLP
4 × 10 7
2 × 10 6
2 × 10 4
2 × 10 3
M. cath.
control
4 × 10 5
3 × 10 5
5 × 10 4
2 × 10 4
71257 C+
ALLP
3 × 10 5
2 × 10 5
3 × 10 3
—
71295 C+
control
2 × 10 7
1 × 10 7
3 × 10 6
6 × 10 5
ALLP
2 × 10 7
5 × 10 6
2 × 10 6
3 × 10 5
C+ = beta-lactamase producing
A dose response curve was made up based on the bactericidal effect on S. pneumoniae 10175 at different levels of administration of ALLP compared with control (no addition). thereby ALLP was administered at 0.1 mg/ml, 0.5 mg/ml, and 1.0 mg/ml, respectively. As little as 0.1 mg/ml of ALLP provides a bactericidal effect on S. pneumoniae.
The viable counts were further determined using different control proteins, viz. bovine serum albumine (BSA), aiphalactal-bumine (bovine origin), lactoferrin (bovine origin) in a concentration of 10 mg/ml, and control (no protein). These proteins had no bactericidal effect on S. pneumoniae 10175.
A new form of alpha-lactalbumin (ALLP) with anti-adhesive activity and bactericidal effect against the respiratory tract pathogens S. pneumoniae and H. influenzae was thus isolated and characterized from a human milk sample. Commercial human or bovine alpha-lactalbumin lacked anti-adhesive activity in the assay system. A portion of the commercial human and bovine alpha-lactalbumin was converted to active form by ion exchange chromatography. The active and non-active forms of alpha-lactalbumin showed different mobilities on gel chromatography and their staining patterns on gel electrophoresis were also different. By ion-desorption mass spectrometry analysis, ALLP was found to be in the trimeric form, whereas commercial alpha-lactalbumin was monomeric. The activated forms of commercial human and bovine alpha-lactalbumin showed gel pattern similar to the trimeric form. A portion of the monomeric form of alpha-lactalbumin was separated from the multimeric form and was found to be inactive in inhibiting the adherence of both S. pneumoniae and H. influenzae . The three forms of alpha-lactalbumin (mono, di and tri) existed in some sort of equilibrium after ion-exchange chromatography and could not successfully be separated from each other. This proposes that the active anti-adhesive alpha-lactalbumin (ALLP) is a multimeric form not previously identified in human milk.
The identification of ALLP in a previous case in preparation was a result of its purification being monitored by the biological activity (16). It retained all of the anti-adhesive activity of casein and thus could be followed during the purification procedures. This form of alpha-lactalbumin has not previously been disclosed to be present in human milk. The early studies of the present inventors showed that the anti-adhesive effect of human milk against S. pneumoniae and H. influenzae was independent from the specific antibody activity and was concentrated in a casein fraction (15). Casein was, however, found to have both a bactericidal effect and an anti-adhesive effect. A bactericidal effect was present and was found to be more pronounced against S. pneumoniae than H. influenzae . The anti-adhesive activity remained intact after removal of the fatty acids from casein. The mechanism of adhesion inhibition of ALLP was found to be independent from its carbohydrate content. Carbohydrate analysis of ALLP showed the presence of only one monosaccharide unit associated with the molecule. Removal of this monosaccharide unit by glucosidase treatment did not alter the anti-adhesive effect of ALLP. Also since the commercial forms of human and bovine alpha-lactalbumin could be activated by ion-exchange chromatography, it is very unlikely that the carbohydrate play any role in the anti-adhesive or bactericidal effect of ALLP tested by the biological analysis system.
Being predominantly a whey protein, alpha-lactalbumin is usually purified from the alpha-lactalbumin rich fractions of whey. Since the monomeric form and the multimeric forms have different mobilities on gel chromatography, the active multimeric forms are lost during the purification procedures. It is thus not surprising that the commercial preparations of alpha-lactalbumin lacked anti-adhesive properties in the present system. Genetic variants of alpha-lactalbumin have been isolated from milk of other mammals including bovine. Most of these forms consist of four disulphide bonds and a form of bovine alpha-lactalbumin with three disulphide bonds have also been isolated (5). The physiological role of these different forms of alpha-lactalbumin is not known. The present data demonstrate that the monomeric alpha-lactalbumin completely lacked biological activity in the present system. Aggregation and polymerization may therefore be an important event in the anti-adhesive activity of ALLP against S. pneumoniae and H. influenzae.
The present data demonstrate that the multimeric alpha-lactalbumin is active in adhesion inhibition of the respiratory tract pathogens and can thus play a role in the protection against respiratory and gastro-intestinal infections. It is also active as a bactericide on at least S. pneumoniae , even those being resistant to antibiotics.
Comments
S. pneumoniae and H. influenzae are important causes of morbidity and mortality in all age groups. Respiratory tract infections, e.g., meningitis, otitis, and sinusitis are caused by bacteria which enter via the nasopharynx. Colonization at that site may thus be an important determinant of disease (18). The finding that a specific alpha-lactalbumin derived from human as well as bovine milk inhibits attachment of both species opens the possibility to prevent colonization by specific interference of attachment using these structures. The bactericidal effect is hereby of importance as well.
The importance of the antimicrobial molecules is shown by the protection against infections which is seen in breast-fed babies. Breast-fed babies have a reduced frequency of diarrhoea, upper respiratory tract infections and acute otitis media (AOM). The bacterial species discussed in this application are the most frequent bacterial causes of AOM, viz. Haemophilus influenzae and Streptococcus pneumoniae.
As evident from the data shown the alpha-lactalbumin obtained from the human or bovine milk inhibits the attachment of S. pneumoniae and H influenzae to human respiratory tract epithelial cells in vitro.
TABLE 3
Bacterial adhesion to oropharyngeal cells after incubation with
active human milk, casein, and casein fractions obtained after
ion-exchange chromatography on DEAE-Trisacryl
Adhesion
S. pneumoniae
H. influenzae
Sample
Mean (%)
Mean (%)
Saline control
150 (100)
200 (100)
Human milk
25 (17)
70 (35)
Casein
4 (3)
10 (5)
Pool VI
14 (9)
22 (11)
Pool K
3 (2)
17 (9)
Pool L
159 (100)
178 (89)
TABLE 4
Bacterial adhesion to oropharyngeal cells after incubation
with human alpha-lactalbumin and the fractions obtained after
ion-exchange chromatography and gel chromatography.
Adhesion
S. pneumoniae
H. influenzae
Sample
Mean (%)
Mean (%)
Saline control
138 (100)
130 (100)
Human alpha-lactalbumin
124 (90)
110 (85)
Pool LA 2
4 (3)
9 (7)
Pool LA
123 (93)
76 (58)
TABLE 5 Bacterial adhesion to oropharyngeal cells after incubation with bovine alpha-lactalbumin and the fractions obtained after ion-exchange chromatography and gel chromatography. Adhesion S. pneumoniae H. influenzae Sample Mean (%) Mean (%) Saline control 138 (100) 130 (100) Bovine alpha-lactalbumin 130 (94) 99 (76) Pool BL 2 3 (2) 18 (14)
Applications
The alpha-lactalbumin of the present invention can be administered in the form of an oral mucosal dosage unit, an injectable composition, or a topical composition. In any case the protein is normally administered together with commonly known carriers, fillers and/or expedients, which are pharmaceutically acceptable.
In case the protein is administered in the form of a solution for topical use the solution contains an emulsifying agent for the protein together with an diluent which can be sprayed into the nasopharynx, or can be inhaled in the form of a mist into the upper respiratory airways.
In oral use the protein is normally administered together with a carrier, which may be a solid, semi-solid or liquid diluent or a capsule. These pharmaceutical preparations are a further object of the present invention. Usually the amount of active compound is between 0.1 to 99% by weight of the preparation, preferably between 0.5 to 20% by weight in preparations for injection and between 2 and 50% by weight in preparations for oral administration.
In pharmaceutical preparations containing a protein of the present invention in the form of dosage units for oral administration the compound may be mixed with a solid, pulverulent carrier, as e.g. with lactose, saccharose, sorbitol, mannitol, starch, such as potatoe starch, corn starch, amylopectin, cellulose derivatives or gelatine, as well as with an antifriction agent such as magnesium stearate, calcium stearate, polyethylene glycol waxes or the like, and be pressed into tablets. Multiple-unit-dosage granules can be prepared as well. Tablets and granules of the above cores can be coated with concentrated solutions of sugar, etc. The cores can also be coated with polymers which change the dissolution rate in the gastrointestinal tract, such as anionic polymers having a pk a of above 5.5. Such polymers are hydroxypropylmethyl cellulose phtalate, cellulose acetate phtalate, and polymers sold under the trade mark Eudragit S100 and L100.
In the preparation of gelatine capsules these can be soft or hard. In the former case the active compound is mixed with an oil, and the latter case the multiple-unit-dosage granules are filled therein.
Liquid preparations for oral administration can be present in the form of syrups or suspensions, e.g., solutions containing from about 0.2% by weight to about 20% by weight of the active compound disclosed, and glycerol and propylene glycol. If desired, such preparations can contain colouring agents, flavouring agents, saccharine, and carboxymethyl cellulose as a thickening agent.
The daily dose of the active compound varies and is dependent on the type of administrative route, but as a general rule it is 1 to 100 mg/dose of active compound at peroral administration, and 2 to 200 mg/dose in topical administration. The number of applications per 24 hrs depend of the administration route, but may vary, e.g. in the case of a topical application in the nose from 3 to 8 times per 24 hrs, i.a., depending on the flow of phlegm produced by the body treated in therapeutic use. In prophylactic use the number may be on the lower side of the range given.
The topical form can preferably be used in prophylactic treatment, preferably in connection with an infection caused by a rhinitis virus.
The protein can also be used as an additive in infant food, particularly for prophylactic reasons, in order to supply the casein in an easy way to the child. Infants normally reject pharmaceuticals for different reasons. The food product can thus be in the form of a pulverulent porridge base, gruel base, milk substitute base, or more complex food product as of the Scotch collops type, comprising vegetables and meat pieces, often in disintegrated form.
In the case of protein administration to animals they are normally added to the feedstuffs, which besides the protein contains commonly used nutrients.
In accordance with a further aspect of the invention there is provided a process for determining the presence of S. pneumococci and H. influenzae in a sample taken from the respiratory tract of an animal or human. This process is based on the technique of determining the degree of interaction between the bacteria of the sample and a composition of the present invention. Such interaction may be determined by inhibition or induction or the adherence of the bacteria to cells or other surfaces.
REFERENCES
1. McKenzie, H. A., White, F. H. Jr Adv. Protein Chem. 41:173, 1991
2. Hopper, K. E. and McKenzie, H. A. Biochim. Biophys. Acta 295:352, 1973
3. Schmidt, D. V. and Ebner, K. E. Biochim. Biophys. Acta 263:714, 1972
4. Maynard, F. J. Dairy Res. 59:425, 1992
5. Barman, T. E. Eur J. Biochim. 37:86, 1973
6. Readhead, K., Hill, T. and Mulloy, B. FEMS Microbiol Lett. 70:269, 1990
7. Gilin, F. D., Reiner, D. S. and Wang, C. S. Science 221:1290, 1983
8. Fiat, A.-M., and Jolles, P. Mol. Cell Biochem. 87:5, 1989
9. Matthews, T. H. J., Nair, C. D. G., Lawrence, M. K. and Tyrrell, D. A. J. Lancet, December, 25:1387, 1976
10. Andersson, B., Dahmén, J., Frejd, T., Leffler, H., Magnusson, G., Noori, G., and Svanborg, C., J. Exp. Med., 158:559, 1983
11. Svanborg, C., Aniansson, G., Mestecky, J., Sabharwal, H., and Wold, A. In Immunology of milk and the neonate, J. Mestecky ed. Plenum Press, New York, 1991
12. Svanborg-Edén, C. and Svennerholm, A.-M., Infect. Immun. 22:790, 1978
13. In Microbial lectins and agglutinins, properties and biological activity, Mirelman, D., Wiley, New York, 1986
14. Andersson, B., Porras, D., Hansson, L. {dot over (A)}., Lagerg{dot over (a)}rd, T. and Svanborg-Edén, C. J. Infect. Dis. 153:232, 1986
15. Aniansson, G., Andersson, B., Lindstedt, R., and Svanborg, C., Microbial Pathogenesis 8, 365, 1990
16. Sabharwal, H., Hansson, C., Nilsson, A. K., Saraf, A., Lönnerdahl, B., and Svanborg, C. 1993, submitted
17. Lacks, S., and Hotchiss, R. D. Biochim. Biophys. Acta, 38:508, 1960
18. Branefors-Helander, P. Acta Pathol. Microbiol. Immunol. Scand. (B), 80:211, 1972
19. Porras, O., Svanborg Edén, C., Lagerg{dot over (a)}rd, T., and Hansson, L. {dot over (A)}. Eur. J. Clin. Microbiol., 4, 310–15, 1985
20. Vanaman, T. C., Brew, K., and Hill, R. L. J. Biol. Chem. 245:4583, 1970
21. Beachey, E. H., J. Infect. Dis. 143, 325, 1981
22. Andersson, B., Beachey, E. H., Tomasz, A., Tuomanen, E., and Svanborg, C., Microbial Pathogenesis, 4, 267, 1988
23. Andersson, B., Eriksson, B., Falsén, E., et al Infect. Immun. 32, 311–17, 1981
|
The present invention relates to the use of alpha-lactalbumin in the preparation of preparations to be used in therapeutic or prophylactic treatment and/or for diagnostic use for infections, preferably of the respiratory tract, caused by bacteria, in particular S. pneumoniae and/or H. influenzae . The present invention further relates to essentially pure protein complexes comprising alpha-lactalbumin and the use of these protein complexes for therapeutically or prophylactically treating a bacterial infection, especially infections of the respiratory tract caused by S. pneumoniae and/or H. influenzae.
| 0
|
BACKGROUND
The present invention relates to devices and/or systems for regulating the temperature in a building, and to methods of making and using such devices and/or systems. In some embodiments, it relates to regulating building temperatures using so-called “green energy,” e.g. using solar and geothermal energy, heat transfer and temperature gradient principles, applicable thermal energy and transfer principles, and structures and/or features of the building to heat and cool the building.
Solar and geothermal energy are excellent sources of green energy, i.e. energy typically involving lower levels of carbon dioxide than, for example, burning coal or oil. They are also useful and have been used for temperature regulation in buildings. While there are various systems and methods that use green energies, there is a lack in the art of temperature regulation systems and/or methods optimally harnessing them to cool and heat buildings across different seasons. Additionally, many known methods and systems rely heavily on supplemental energy sources, e.g. fans, pumps, etc., for temperature regulation.
Thus, there exists a need for a system and method for efficiently regulating the temperature of a building using radiant solar and geothermal energy. Particularly, there exists a need for a system and method for storing and utilizing solar and geothermal energy such that a building may be kept at a stable temperature across seasons and outside temperature variations.
SUMMARY
In one embodiment, the present invention comprises a method for regulating the interior temperature of a building, the building including at least one thermal mass for receiving and holding heat and/or remaining relatively colder when it is not receiving heat than when it is, distribution vents and an air return, the method comprising: receiving and holding heat and/or cold in the at least one thermal mass, enabling an air flow across and/or adjacent to the at least one thermal mass using the distribution vents and building shape, and returning the air flow to the at least one thermal mass via the air return, wherein the temperature of the at least one thermal mass is distributed through the building by the air flow. In some embodiments, the air flow is convective and, in some embodiments, wholly free or natural, i.e., not driven to flow by an external power such as a fan.
In one embodiment, the present disclosure relates to a method for regulating the temperature of a building, including capturing thermal energy in an energy sink, store or storage structure associated with the building. Air is enabled to flow freely and/or naturally from the energy store throughout the building via distribution vents, and is returned to the energy store via a return air shaft. The thermal energy is thus distributed through the building by a cyclical air flow enabled and/or facilitated by structures, features, the arrangement of the structures and/or features, and/or the shape of the building.
In one embodiment, a building and system in accordance with the present invention operates passively under the thermal principle that everything wants to be the same temperature. During the day, a thermal mass, or energy sink or storage structure, is exposed to sunlight and absorbs and holds heat; when the energy sink or storage structure is warmer than the building, it releases heat. When it is cooler, it absorbs heat. Thus, a cyclical air flow within the building is generated.
The present invention relates to a temperature regulation system and method wherein a building according to the present invention efficiently utilizes solar and geothermal energy to heat and cool the building. In some embodiments, a solarium collects and stores radiant energy from the sun, and conduction draws cold from the ground through the floor or footprint of the building. The solar and/or geothermal energy is then utilized to heat and/or cool the building through conduction and convection, which are enabled, facilitated and/or improved by air flow characteristics of the building. Because the system and method in accordance with the present invention involve using renewable energy sources and passive, or natural or free, air flows, they have a low ecological impact.
While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the disclosure. As will be realized, the various embodiments of the present disclosure are capable of modifications in various obvious aspects, all without departing from the spirit and scope of the present disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an embodiment of a building in accordance with the present invention.
FIG. 2 is an elevational view of an embodiment of a solarium of a building in accordance with the present invention.
FIG. 2 a depicts an embodiment of the solarium including an embodiment of solarium roof exhaust vents.
FIG. 3 shows a portion of a building in accordance with the present invention.
FIG. 4 shows an embodiment of a foundation in accordance with the present invention.
FIG. 5 is an exploded view of an embodiment of a building in accordance with the present invention.
FIG. 5 a is an exploded view of an embodiment of a building in accordance with the present invention.
FIG. 6 is an exploded view of a portion of an embodiment of a building in accordance with the present invention.
FIG. 7 is a cross-sectional view of the base of FIG. 4 .
FIG. 8 is a perspective view of a portion of a building in accordance with the present invention.
FIG. 9 is a perspective view of a portion of a building in accordance with the present invention.
FIG. 10 is an exploded view, partially in cross-section, depicting an airflow through an embodiment of a building in accordance with the present invention.
FIG. 10 a , partially in cross-section, depicts an airflow through an embodiment of a building in accordance with the present invention.
FIG. 11 is an exploded view, partially in cross-section, depicting an airflow through an embodiment of a building in accordance with the present invention.
FIG. 11 a , partially in cross-section, depicts an airflow through an embodiment of a building in accordance with the present invention.
FIG. 12 is a perspective view of a portion of a building in accordance with the present invention depicting interaction of sunlight and the building.
FIG. 13 is an elevational schematic of an embodiment of a building in accordance with the present invention depicting interaction of sunlight and the building.
FIG. 14 is an exploded view of an embodiment of a building in accordance with the present invention.
FIG. 15 is a perspective view of a portion of a building in accordance with the present invention, partially exploded.
FIG. 16 depicts an embodiment of a portion of a building in accordance with the present invention.
FIG. 17 depicts an embodiment of a portion of a building in accordance with the present invention.
FIG. 18 depicts an embodiment of a portion of a building in accordance with the present invention.
FIG. 18 a depicts an embodiment of a portion of a chimney in accordance with the present invention.
DETAILED DESCRIPTION
Any reference to “the invention” herein shall not be construed as a generalization, limitation or characterization of any subject matter disclosed herein and shall not be considered to be an element or limitation of the appended claims except if and/or where explicitly recited in a claim(s). With regard to fastening, mounting, attaching or connecting components, unless specifically described as otherwise, conventional mechanical fasteners and methods may be used. Other appropriate fastening or attachment methods include adhesives, welding and soldering, including with regard to an electrical system, if any. In embodiments with electrical features or components, suitable electrical components and circuitry, wires, wireless components, chips, boards, microprocessors, inputs, sensors, outputs, displays, control components, etc. may be used. Generally, unless otherwise indicated, the materials for making embodiments and/or components thereof may be selected from appropriate materials such as metal, metallic alloys, ceramics, plastics, etc. Unless otherwise indicated specifically or by context, positional terms (e.g., up, down, front, rear, distal, proximal, etc.) are descriptive not limiting. Same reference numbers are used to denote same parts or components.
FIG. 1 is a perspective view of an embodiment of a building in accordance with the present invention. The building 20 , and the temperature regulation system it and/or its features provides and/or enables, includes an interior building space 22 to be temperature regulated, a solarium 24 having one or more solarium windows 26 , an energy storage pool 28 , an apron 30 , an exchange wall 32 , a base 34 , and a chimney 36 , and a computer control system 38 . The energy storage pool 28 , exchange wall 32 , base 34 , and chimney 36 may be referred to and/or thought of as an energy absorber, a thermal mass or simply the mass. The building 20 allows for heat to be received and collected or held by the mass, and for heated and/or cooled air to be cycled through the building 20 back to the mass. The computer system 38 , including a suitable processor and/or control unit and temperature sensors and displays suitably located in the building, may be operably coupled to the solarium windows 26 to mitigate and control heat loss and gain. This may be accomplished by opening and closing, in some embodiments automatically in response to sensed temperatures, the windows 26 to cool and/or heat the building 20 .
The solarium 24 receives, collects and stores radiant energy from the sun. This activates cycles of convection and conduction. Conduction allows cool temperature to be pulled from concrete, e.g. in and/or below the base 34 , and/or cool ground beneath the building 20 . Convection means air, heated by the mass, in turn heated by the sun, flows and is distributed throughout the building 20 cyclically. The stored energy combined with the building design moderates and creates a balanced temperature year-round. The energy storage mass provides heat for long periods of cold without sun and, conversely, cool for periods of greater warmth.
In one embodiment, shown in FIG. 2 , the solarium 24 may be designed to include 45 degree angled windows 26 to catch both the morning and afternoon sun at the southeast and southwest corners, and the roof of the building, and/or solarium, may include one or more skylights 40 . The skylights 40 may be configured to be operable, e.g. openable, to exhaust heat. Suitable sensors (not shown) may be located throughout the building 20 , including near the uppermost or highest interior portion of the building where heat may collect. Opening the skylights 40 , e.g. using small motors coupled to the skylights 40 and controlled by the computer system 38 , vents excess hot air. Other and/or additional vents 41 , including passive exhaust and/or attic-type vents may be used as well. See, for example, FIG. 2 a . The depicted and described configuration of the solarium 24 maximizes the exposure of the solarium 24 to the sun. Large glass areas allow for maximum capture and storage of the solar radiant energy. In some embodiments, other angles may be used to maximize or minimize sunlight capture by the solarium 24 . The precise angles and exposure to the sun may vary depending on the location of the building 20 . Exposure to sunlight and capture of heat may be further regulated through the use of window coverings, such a blinds or shades, insulated glass or so-called “smart” glass. Such peripherals may expand or restrict the amount of solar energy coming through the solarium glass. Such peripherals, including optional interior, operable glass or window walls 27 may be used to control energy and/or air flow entering the rest of the building 20 . Of course, window coverings and/or smart glass may further be operably coupled to the computer and/or sensor system 38 to automatically vary the window's transparency to sunlight to adjust energy capture. Sun exposure to the solarium 24 may further be regulated through landscaping options, such as planting trees outside the solarium windows 26 . For example, as latitude increases and decreases, sunlight strikes the building 20 at different angles. In some embodiments, as depicted in FIGS. 12 and 13 , the angles associated with the solarium 24 may be selected to facilitate capturing and/or reflecting solar energy at a particular location. The solarium apron 30 , formed of, e.g. concrete, may encompass the area below and/or surrounding the solarium windows, and lies between the outside and the pool 28 . Together and/or separately, the apron 30 and pool 28 may be referred to and/or thought of as the main collectors of solar heat. In some milder climates, the pool 28 may not be necessary for heat energy storage. In some embodiments, the pool 28 may be used for potable water storage.
FIG. 3 depicts an embodiment of the solarium interior and the apron 30 . The apron 30 may be black to help collect the maximum radiant energy available, and may be thin to facilitate quick heat transfer and conduction to the pool 28 . Conduction may be pulled down into the pool 28 , then back into the rest of the building for storage. In some embodiments, the solarium 24 may be 25% of the depth of the building to provide a suitable amount of radiant energy capture and storage.
Referring to FIGS. 2 , 5 , 11 and 12 , the mass functions as a thermal capacitor, i.e., the pool 28 , chimney 36 , exchange wall 32 , and base 34 all permit energy storage. The centrally located chimney 36 may serve as a structural center support for the entire building 20 , in addition to its energy storage function. The mass experiences sunlight and captures energy during the daylight hours through the solarium 24 , and then functions as a heat store or sink during night, as well as during days without sunlight.
FIG. 4 and FIG. 11 a illustrate embodiments of a foundation 46 for a portion of the building 20 , e.g. under the solarium 24 and the rest of the building. In some embodiments, the foundation 46 may include and/or be thought of as comprising, a footing or base 34 , a solarium base 35 , exchange wall posts 48 , the foundation element 37 and horizontal fins 50 , which also may support the first floor 39 . The exchange wall posts 48 may be one point of contact with the ground. The base 34 may be another point of contact with the ground for cooling purposes, and may be set according to latitude and climate, and in some embodiments, may be made of concrete other suitable material. The base 34 may be set on undisturbed ground, and may include 6 inches of crushed rock or other suitable material (not shown) in the center with rigid insulation. The perimeter of the base 34 may also function as a vapor harrier. In some embodiments, the base 34 may not be part of the heat store, and instead may be part of the outside wall 52 . Multiple, and variable, areas and/or degrees of contact or isolation make a building designed in accordance with the present invention adaptable to many latitudes. For example, more insulation or less insulation may be used between the foundation and the ground depending on latitude and climate. The relatively constant temperature of the ground can be used to draw and store heat or, in the summer, cool, thereby helping to maintain a relatively constant temperature in the mass.
As shown in FIGS. 5 and 5 a , above the foundation, i.e. the base 34 and fill material, first floor concrete walls 56 may also be isolated from the foundation according to the location of the building. This may determine the amount and length of heat storage available. Less isolation in southern latitudes will create a shorter heating storage period and cooler level in summer. To further facilitate cold air falling, a door 58 may be added in the air return shaft 60 (see FIGS. 10 and 11 ).
As shown in FIG. 6 , utilities 62 may be run inside to save breaks of outside walls. The utility channel 62 may further run next to the chimney 36 as pictured, and/or on both sides and/or inside the chimney, as well as in and/or through the foundation or where convenient. FIG. 6 provides another view of the first floor walls and foundation, which is insulated and provides a vapor barrier from the outside. This arrangement turns the basement into heat store, augmenting the mass. Also observable in FIG. 6 are the raised basement floors 64 , which may rest on the horizontal fins 50 .
FIG. 7 illustrates the foundation 46 , and the horizontal fins 50 , exchange wall 32 , and pool 28 . Surrounding the pool 28 may be one or more cold air vents 68 to facilitate cool air flow during hot days. In some embodiments, there may be one vent 68 on each side of the pool 28 . The pool 28 may further abut the exchange wall 32 . Within the exchange wall 32 are further vents 68 to promote air flow along the pool/exchange wall 32 to further stimulate cool air transfer. Air is cycled through the exchange wall vents 68 , which exit at the base of the horizontal fins 50 , to be guided among the horizontal fins 50 . The foundation and pool function as cold storage. Cold from the footings and/or earth is backed up into the foundation to fuel cycling through the vents 68 . The vents 68 may be controlled, e.g. opened and/or closed, by suitable operators coupled to the computer/sensor systems 38 to help maintain a substantially constant and stable temperature, e.g. by closing off or separating the solarium from the main living space of the building 20 . The position, structural and operational relationships of building components, e.g., the solarium, solarium base, chimney, exchange wall and foundation may be selected based on, for example, climate and/or the location of the building. With reference to FIG. 18 a , further vents 69 for controlling and/or modifying the air flow through the building 20 may be associated with the chimney 36 .
FIG. 8 further illustrates the structural relationship and/or interaction between the horizontal fins 50 , exchange wall 32 , and the pool 28 . In some embodiments, the pool 28 may be covered. The first floor (see FIG. 11 a , 39 ) may rest on the horizontal fins 50 , and may abut the exchange wall 32 to further promote heat and/or cold transfer. The convection airflow or cycle runs under the raised basement floor, hits the exchange wall 32 , and is pulled underneath through the vents 68 at the base.
FIG. 9 is a cross section of the pool 28 and apron 30 . As radiant energy is pulled into the pool, heat goes to cold. Part of the convection cycle occurs in the pool 28 . The pool cover (if used), exchange wall 32 , and chimney 36 (not shown in FIG. 9 ) receive direct sunlight. The exchange wall 32 and chimney connect directly to the mass in the first floor, and therefore help to maintain a constant temperature. In colder northern climates, the pool 28 may be isolated from the ground. This may help prevent overcooling or freezing. As cold penetrates the solarium windows 26 above the cold air vents 68 , it falls through the vents 68 into storage underneath.
FIGS. 10 , 10 a , 11 , 11 a and 11 b illustrate an embodiment of an air flow cycle for maintaining constant temperature according to the method of the present invention. Starting at the base 34 of the building 20 , air rising from the exchange wall 32 , pool 28 , and chimney mass cycles inside the building 20 to distribute heat or cold throughout the building 20 . For example, heat rises from the mass adjacent to the first floor, and is guided into the second floor by a third floor extension 70 over the solarium as shown. The remainder of the air continues to rise to the third floor 72 . As the warm air rises, it is distributed throughout the home cyclically. As it cools, it may be guided down the return air shaft 60 . The return air shaft 60 may run from the third floor all the way down to the base 34 of the building 20 to facilitate an efficient air cycle. The location of the return air shaft in the pointed structure of the building 20 helps minimize temperature “dead spots” within the building 20 , where temperatures are not regulated due to lack of air flow. The air flow may then encounter the raised basement floor 74 and be guided across the horizontal fins 50 . As the air hits the exchange wall 32 , the heat within the mass may be carried with the air, which may then be pushed out the exchange wall vents 68 , and up into the solarium 24 to continue the cycle.
FIGS. 11 and 11 a provide another view depicting the air flow cycle. Air runs underneath the raised basement floor until it encounters the vents 68 at the base of the exchange wall 32 . The air is then drawn up through the vents 68 against the mass, and the cycle repeats. The heated air then rises up the solarium 24 and into the upper second and third floors 72 to be drawn across the building 20 . As shown, the third floor 72 may be located underneath eaves 78 to provide additional protection from the weather.
FIGS. 12 and 13 depict the varying angles of sunlight that may impact the solarium 24 during different months in different locations. For example, in June at noon, the sun angle may be 73.5 degrees, while in winter, a much more gentle 27 degree. A roof overhang 80 , above and/or part of the solarium 24 , may be selected and/or adjusted for more or less shade coverage to maximize sunlight in colder climates during the winter months, while not permitting overheating during the summer. FIG. 13 is a cross section of the building 20 schematically depicting how the angle of the sun affects heat gain throughout the building 20 .
FIGS. 14 and 15 are exploded views of an embodiment of a building and temperature regulation system, and components of the building 20 , according to an embodiment of the present invention. The building components are commonly numbered in accordance with the preceding Figs. FIG. 15 shows the pool 28 , apron 30 and exchange wall 32 separated from the building 20 to show how the air flow cycle extends under the basement floor 86 above the fins 50 .
FIGS. 16-18 further depict the relationship among building components, including the pool 28 , exchange wall 32 , vents 68 and fins 50 , and how they and their location and structural relationship contribute to the conductive and/or convective flows provided and/or enabled by embodiments of the present invention.
A building and system in accordance with the present invention may be constructed and/or composed of suitable sustainable and/or renewable materials and resources, e.g. wood, stone, recycled material, etc. This can have the added benefit of safer construction and manufacturing processes, while maintaining long lasting structures. While the embodiments illustrated in the Figs. generally reflect a building model with dimensions of 48 feet north to south and a solarium with a depth of 12 feet, the building may be scaled up or down to facilitate larger or smaller needs. Further, the building may be more or less insulated from the ground depending on the climate, and may have suitable insulation between the first floor walls and the ground to prevent heat exchange. In some embodiments, additional vents between interior areas and/or between interior and exterior may be used, and vents may be shifted in location according to circulation needs and/or building location. Within the United States, northern buildings are generally in colder climates and therefore should be capable of storing heat longer, while southern buildings require less heat storage, and therefore less insulation from the ground. Some embodiments according to the present invention may use approximately 25% of the building surface area for windows, and 25% of the building area for heat storage. However, other ratios are also possible while maintaining a substantially constantly regulated building temperature.
An appendix is attached, and shows exemplary specifications, operational and performance factors and calculations for exemplary embodiments of a building and system in accordance with the present invention.
Embodiments of the present invention, including preferred embodiments, have been presented for the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms and steps disclosed. The embodiments were chosen and described to illustrate the principles of the invention and the practical application thereof, and to enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth they are fairly, legally, and equitably entitled.
|
A system and method for regulating the temperature of a building interior, the building including at least one thermal mass for receiving and holding heat, distribution vents and an air return, the method including receiving and holding heat in the at least one thermal mass, enabling an air flow from the at least one thermal mass using the distribution vents, and returning the air flow to the at least one thermal mass via the air return, wherein the air flow tends to maintain a generally constant temperature in the building.
| 8
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a fermentation method for the production of mannitol and to a mannitol dehydrogenase useful for producing mannitol from a variety of readily available carbohydrate substrates, especially fructose and glucose.
2. Description of the Prior Art
Mannitol, a naturally occurring polyol, is widely used in the food, pharmaceutical, medicine and chemical industries (Soetaert et al., Agro Food Ind. Hi - Tech . 6:41-44, 1995). It is used as a sweet-tasting bodying and texturing agent. Mannitol reduces the crystallization tendency of sugars and is used as such to increase the shelf-life of foodstuffs. Crystalline mannitol exhibits a very low hygroscopicity, making it useful in products that are stable at high humidity. It is extensively used in chewing gum. Because of its desirable properties, mannitol is commonly used in the pharmaceutical formulation of chewable tablets and granulated powders. It prevents moisture absorption from the air, exhibits excellent mechanical compressing properties, does not interact with the active components, and its sweet cool taste masks the unpleasant taste of many drugs (Debord et al., Drug Dev. Ind. Pharm . 13:1533-1546, 1987). The complex of boric acid with mannitol is used in the production of dry electrolytic capacitors. It is an extensively used polyol for production of resins and surfactants. Mannitol is used in medicine as a powerful osmotic diuretic and in many types of surgery for the prevention of kidney failure and to reduce dye and brain oedema. Mannitol hexanitrate is a well known vasodilator, used in the treatment of hypertension.
Mannitol is currently produced industrially by high pressure hydrogenation of fructose/glucose mixtures in aqueous solution at high temperature (120-160° C.) with Raney nickel as catalyst. Typically, the hydrogenation of a 50/50 fructose/glucose mixture results in an approximately 30/70 mixture of mannitol and sorbitol (Makkee et al., Starch/Starke 37:136-141, 1985). Therefore about half of the fructose is converted to mannitol and half of it to sorbitol. The glucose is hydrogenated exclusively to sorbitol. As a consequence, the commercial production of mannitol is always accompanied by the production of sorbitol, thus reducing the conversion efficiency of substrate to mannitol (Soetaert et al., 1995, supra).
In recent years, research efforts have been directed towards production of polyols by fermentation and enzymatic means (Vandamme et al. FEMS Microbiol. Rev . 16:163-186, 1995). Yun et al., ( Biotechnol. Letts . 18:35-40, 1996) describe microbial transformation of fructose to mannitol by Lactobacillus sp. KY-107. In shake flask cultures, Yun et al. obtained a final concentration of 70 g mannitol/L from 100 g D-fructose within 80 h at 28° C. Yun et al. ( J. Ferment. Bioeng . 85:203-208, 1998) report the isolation of two mannitol-producing, lactic acid bacteria from kimichi, a traditional Korean food. Lactobaccilus sp. Y-107 transformed fructose to mannitol from the early growth stage, with a 54% conversion yield after 20 h; whereas Leuconostoc sp. Y-002 converted fructose to mannitol more slowly with a 40% yield at 20 h. Yun et al. (1998, supra) describe the pathway for microbial mannitol formation as comprising two mechanisms. In the first mechanism, NADPH-linked mannitol dehydrogenase directs the reduction of fructose. In the second mechanism, fructose-6-phosphate is initially reduced to mannitol-1-phosphate by means of NAD(P)H-linked mannitol-1-phosphate dehydrogenase. The mannitol-1-phosphate is then converted to inorganic phosphate and mannitol by means of a specific mannitol-1-phosphatase.
Korakli et al. ( Adv. Food Sci . (CTML) 22:1-4, 2000) describe the production of mannitol in a fermentation process with selected strains of Lactobacillus sanfranciscensis with the ability to utilize maltose, sucrose and glucose as carbon sources. Cells of strain LTH 2590 were adapted to sucrose, but gave a decreased yield of mannitol production in relation to the fructose content of sucrose.
Itoh et al. (European Patent Number EP0486024, 1992) teaches the use of Lactobacillus sp. B001 (FERM BP-3158) for the production of mannitol, acetic acid and lactic acid on carbohydrate substrates comprising glucose and fructose. Itoh et al. reports obtaining a level of 12.3% mannitol in 23 h with a yield of sugar of 61%. Though being able of use other sugars, such as glucose, galactose, maltose and xylose, strain B001 does not metabolize mannose or trehalose.
SUMMARY OF THE INVENTION
I have now discovered a highly efficient fermentative method for the production of mannitol using a strain of Lactobacillus intermedius , as well as a biochemical method using mannitol dehydrogenase isolated from the L. intermedius strain. Fructose serves as the primary carbon substrate in both the fermentative and biochemical conversions, but important secondary carbon sources include glucose, maltose, mannose, raffinose and galactose.
In accordance with this discovery, it is an object of the invention to provide a fermentative method for production of mannitol.
It is also an object of the invention to introduce a heretofore unrecognized bacterial source for use in efficient conversion of fructose and other carbon sources to mannitol.
Another object of the invention is to provide microbiological and biochemical alternatives to chemical production of mannitol.
Yet another object of this invention is to provide a microbial source of mannitol for use in foods and pharmaceuticals.
A further object of the invention is to provide a novel mannitol dehydrogenase isolated from L. intermedius for use in the biochemical conversion of fructose substrates to mannitol.
Other objects and advantages of the invention will become apparent from the ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a time course of fructose (150 g/L) utilization and mannitol production by Lactobacillus intermedius B-30560 in pH-controlled batch fermentation at 35° C. Symbols: ◯, Fructose; ●, Mannitol; ▴, Lactic acid; ▪, Acetic acid.
FIG. 2 is a time course of fructose (100 g/L) and glucose (50 g/L) co-utilization and mannitol production by Lactobacilus intermedius NRRL B-30560 in a pH-controlled batch fermentation at 37° C. Symbols: ◯, Fructose; □, glucose; ●, Mannitol; ▴ Lactic acid; ▪, Acetic acid.
FIG. 3 are time courses of fructose utilization and mannitol production by Lactobacilus intermedius NRRL B-30560 in pH-controlled fed-batch fermentation at 37° C. Fructose used: 300 g/L (final concentration). Symbols: ◯, Fructose; ●, Mannitol; ▴ Lactic acid; ▪, Acetic acid.
DEPOSIT OF BIOLOGICAL MATERIAL
Lactobacilus intermedius B-3693 described herein was redeposited on Mar. 4, 2002, under the provisions of the Budapest Treaty in the Agricultural Research Culture Collection (NRRL) in Peoria, Ill., and has been assigned Accession number NRRL B-30560. Hereafter, the L. intermedius for use in the invention will be referred to by the B-30560 Accession number.
DETAILED DESCRIPTION OF THE INVENTION
The primary carbon source for use in the method of the invention is fructose, which may in fact be used as the sole carbon source. Secondary carbon sources for use in combination with fructose are glucose, maltose, mannose, raffinose and galactose, without limitation thereto. Unlike Lactobacillus sp. B001 , L. intermedius B-30560 can utilize trehalose very well, but cannot utilize xylose at all. Starch is also useful as a secondary carbon source, provided that glucoamylase is introduced into the fermentation medium to promote saccharification during the course of the fermentation. The amount of secondary carbon source can be up to about 33% (w/w) of the total substrate, though it is preferred that the secondary carbon source constitute less about 25% of the carbon substrate. The secondary carbon source of choice is glucose.
The specific fermentation medium for use in the mannitol production is not necessarily critical, and selection thereof would be within the skill of an ordinary person in the art. A suitable medium would contain sources of protein, amino acids, salts and other growth stimulating components. Exemplary media would be simplified MRS medium [10 g peptone, 5 g yeast extract, 2 g ammonium citrate, 5 g sodium acetate, 0.1 g magnesium sulfate, 0.05 g manganese sulfate and 2 g disodium phosphate per liter (final pH 6.5)] and enriched MRS medium (same as the simplified medium but additionally containing 10 g beef extract and 1.0 ml Tween 80). Sodium acetate may be omitted from the simplified MRS medium. Also, peptone and yeast extract may be replaced with corn steep liquor.
Fermentations may be conducted by combining the carbon source with the medium in any suitable fermentor, and inoculating with the L. intermedius NRRL B-30560. Initial levels of carbon substrate should exceed 50 g/L, and preferably be at least about 100 g/L, or even in excess of 200-300 g/L. The fermentation is carried out either aerobically or anaerobically under conditions conducive to the growth of L. intermedius B-30560 and production of mannitol dehydrogenase. Fermentation temperature should be maintained within the range of at least about 25° C., and less than about 50° C. Preferably, the temperature is at least about 30° C. and less than or equal to about 37° C. The pH of the medium at the commencement of the fermentation is typically within the range of about 6-7, and then is controlled by addition of base at approximately pH 4.5-6.0 as the fermentation progresses. Peak mannitol levels occur shortly after the organism completes its log phase growth, typically within about 24-96 hours post-inoculation. At higher levels of initial carbon substrate, longer periods of fermentation are of course required to maximize mannitol production. In pH-controlled, fed-batch fermentations, initial levels of carbon substrate may be lower than described above, and then supplemented as the fermentation progresses. With corn steep liquor replacing peptone and yeast extract, longer periods of fermentation are required to maximize mannitol production.
Upon completion of the fermentation, mannitol may be recovered from the culture using techniques conventional in the art. For example, when mannitol is present in the culture broth at levels exceeding the solubility limit (180 g/L at 25° C.), it can be recovered from solution by cooling crystallization. In practice, mannitol would be crystallized from the crude fermentation broth by chilling the crude broth to about 4° C. After mannitol recovery, lactic acid and acetic acid can be easily recovered from the fermentation broth by electrodialysis.
Mannitol dehyrogenase, the enzyme responsible for mannitol production in the aforementioned fermentation, can be isolated from the cells by breaking the cells with glass beads.
While not desiring to be bound to any particular theory of operation, it appears that mannitol produced by L. intermedius NRRL B-30560 is derived from the hexose phosphate pathway like other mannitol producing bacteria such as Lactobacillus sp. Y-107 , Leuconostoc sp. Y-002 and Leucononostoc mesenteroides (Yun et al., 1996, supra; Yun et al., 1998, supra; Soetaert et al., 1995, supra). The process makes use of the capability of L. intermedius NRRL B-30560 to utilize fructose as an alternative electron acceptor, thereby reducing it to mannitol with the enzyme mannitol dehydrogenase. In this process, the reducing equivalents are generated by conversion of about one-third fructose to lactic acid and acetic acid. It is thought that enzyme reaction proceeds according to the following (theoretical) equation:
3 Fructose→2 Mannitol+Lactic acid+Acetic acid+CO 2
For fructose and glucose (2:1) co-fermentation, the equation becomes:
2 Fructose+Glucose→2 Mannitol+Lactic acid+Acetic acid+CO 2
The following examples are intended to further illustrate the invention, without any intent for the invention to be limited to the specific embodiments described therein.
EXAMPLE 1
Screening of Bacterial Strains
Selection of Strains.
Seventy two bacterial strains were obtained from the ARS Culture Collection, National Center for Agricultural Utilization Research, Peoria, Ill. These strains were (with NRRL numbers): Lactobacillus acidophilus B-4495, L. amylophilus B-4436 , L. amylovorus B-4545 , L. animalis B14177 , L. arabinosus B-787 , L. brevis B-1836 , L. buchneri B-1860 , L. bulgaricus B-548 , L. casei B-1922 , L. cellobiosus B-1840 , L. coryniformis B-4391 , L. delbrueckii B-763 , L. fermentum B-1915 , L. fructivorans B-4000 , L. gasseri B-14168 , L. gramminis B-14857 , L. helveticus B-1935 , L. intermedius B-3693 , L. jensenii B-4550 , L. leichmanii B-4525 , L. mali B-4565 , L. paracasei B-4564 , L. pentosus B-473 , L. plantarum B-4496 , L. reuteri B-14172 , L. rhamnosus B-442 , L. salivarius B-1949 , Leuconostoc amelibiosum B-742 , L. citrovorum B-1147 , L. mesenteroides subsp. dextranicum B-1120 , L. mesenteroides subsp. mesenteroides B-1209 , L. paramesenteroides B-3471 , L. oenos B-3474 , L. lactis B-3468 , Pediococcus acidilactici B-1153 , P. pentosaceus B-14009 , Lactococcus lactis B-1821 , Streptococcus dysgalactiae B-688 , Enterococcus faecalis B-537 , E. faecium B-1295 , E. casseliflavus B-3502 , E. hirae B-14926 , Bacillus subtilis NRS-744 , B. cereus B-3711 , B. licheniformis NRS-1264 , B. megaterium B-14308 , B. pumilus B-14292 , B. coagulans NRS-609 , B. smithii NRS-173 , B. amyloliquefaciens B-14394 , B. mycoides NRS-273 , Paenibacillus polymyxa B-367 , P. peoriae B-14750 , P. amylolyticus B-377 , P. illinoisensis NRS-1356 , P. chondroitinus B-14420 , P. alginolyticus NRS-1347 , P. pulvifaciens B-14166 , P. lautus NRS-666 , P. validus NRS-1000 , P. pabuli B-14213 , P. thiaminolyticus B-14605 , P. macerans B-172 , P. glucanolyticus B-14680 , P. curdlanolyticus B-23243 , P. apiarius NRS-1438 , Micrococcus luteus B-287 , M. kristinae B-14845 , Brevibacillus brevis NRS-604 , B. agri B-1158 , B. choshinensis B-23247 and B. reuszeri NRS-1206.
Screening Medium and Culture Conditions.
The bacterial strains listed above were evaluated for cell growth, residual substrate and product yield. The strains were cultivated on a screening medium designated as enriched MRS contained 10 g peptone, 10 g beef extract, 5 g yeast extract, 1.0 ml Tween 80, 2 g ammonium citrate, 5 g sodium acetate, 0.1 g magnesium sulfate, 0.05 g manganese sulfate and 2 g disodium phosphate per liter (final pH 6.5). The medium and the substrate (glucose or fructose 5%, w/v) were sterilized separately at 121° C. for 15 min. A 125-ml Erlenmeyer flask containing 50 ml MRS medium with substrate was inoculated with a loopful of cells taken from a stock slant and incubated at 30° C. on a rotary shaker (130 rpm). Samples were periodically withdrawn for evaluation.
Strains producing mannitol from fructose were: L. brevis B-1836 , L. buchneri B-1860 , L. cellobiosus B-1840 , L. fermentum B-1915 , L. intermedius B-3693 (NRRL B-30560), Leuconostoc amelibiosum B-742 , L. citrovorum B-1147 , L. mesenteroides subsp. dextranicum B-1120, and L. paramesenteroides B-3471. In addition, all these strains produced lactic acid and acetic acid. Among these nine strains, L. intermedius NRRL B-30560 produced mannitol at a higher rate than the other strains.
EXAMPLE 2
Mannitol Production at Four Fructose Concentrations
Fermentation Experiment Protocol.
Fermentation experiments were carried out with L. intermedius NRRL B-30560 in simplified MRS medium (without beef extract and Tween 80). For seed culture, a 250 ml Erlenmeyer flask containing 50 ml of the medium with fructose (2%, w/v) was inoculated with a loopful of cells taken from a stock slant and incubated at 30° C. on a rotary shaker (130 rpm) for 24 h.
Batch culture experiments were performed in pH-controlled 500 ml fleakers with an initial medium volume of 300 ml at either 30° C. or 37° C. essentially as described by Bothast et al. [ Biotechnol. Lett . 16:401-406. (1994)]. The pH was maintained at 5.0 by adding 2-8 N NaOH. Cultures were stirred magnetically using 1.5 inch stir-bars, at 130 rev/min. Samples were withdrawn periodically to determine cell growth, sugar utilization and production yield.
Effect of Fructose Concentration.
Batch cultures were conducted at four concentrations of fructose substrate: 150, 200, 250, and 300 g/L. Cell growth was monitored by measuring optical density of the appropriately diluted culture broth at 660 nm. Sugar utilization and product analysis were performed by high performance liquid chromatography (HPLC). The bacterium L. intermedius NRRL B-30560 produced mannitol, lactic acid and acetic acid when grown on fructose in pH-controlled fermentation (Table I). The mannitol yields were 107.6±0.5, 138.6±6.9, 175.6±5.9 and 198.3±11.0 g/L at 150, 200, 250, and 300 g/L fructose, respectively. A typical time course of fructose utilization and mannitol, lactic acid and acetic acid production at 150 g/L substrate concentration is shown in FIG. 1 . The time of maximum mannitol yield varied greatly from 20 h at 150 g/L fructose to 136 h at 300 g/L fructose concentration. Also, there was a long lag period of about 72 h in growth and fructose utilization at 300 g/L fructose concentration in comparison to the lag period of about 16 h at 250 g/L fructose. However, the product patterns and yields were not much dependent on fructose concentration. The bacterium transformed fructose to mannitol from the early growth stage and it did not consume mannitol even when all supplied fructose was utilized. Moreover, the product (mannitol, lactic acid and acetic acid) concentration continued to increase slightly upon further continuation of the fermentation in most cases. The maximum cell growth (A 660 of 9.6±0.8 in 16 h) was obtained at fructose concentration of 150 g/L. The average maximum cell densities (A 660 ) were 4.7±0.4 in 24 h, 5.3±1.0 in 64 h and 6.5±0.8 in 136 h at fructose concentrations of 200, 250 and 300 g/L, respectively.
Small white needle-like crystals of mannitol appeared upon keeping the cell-free fermentation broth of 300 g/L fructose at 4° C. This suggests an efficient product recovery scheme for mannitol.
EXAMPLE 3
Mannitol Production on Fructose and Secondary Substrate
The procedure of Example 2 was repeated, except that one third of fructose was replaced with other substrates including glucose, maltose, starch plus glucoamylase (simultaneous saccharification and fermentation, SSF), mannose, galactose, xylose, arabinose, cellobiose, raffinose and glycerol. In a separate run, two-thirds of fructose was also replaced by sucrose. The results of mannitol production by L. intermedius NRRL B-30560 in the two-substrate system is presented in Table II.
It is clear that one-third of fructose can be replaced with glucose, starch with glucoamylase, maltose, mannose, raffinose and galactose. Two-thirds of fructose can also be replaced by sucrose. Even though arabinose was co-utilized with fructose, it did not contribute to mannitol production. The arabinose-fructose co-substrate also led to a considerable increase in the production of lactic acid and acetic acid. The bacterium was not able to co-utilize lactose, glycerol, cellobiose and xylose with fructose. A time course of fructose (100 g/L) and glucose (50 g/L) co-fermentation is shown in FIG. 2. L. intermedius NRRL B-30560 co-utilized fructose and glucose simultaneously and produced very similar quantities of mannitol, lactic acid and acetic acid in comparison with fructose only. The conversion efficiency of fructose to mannitol was 96%. The glucose was converted to lactic acid and acetic acid which were partially neutralized during fermentation by adding NaOH to control the pH at 5.0.
EXAMPLE 4
Mannitol Production in Fed-Batch Fermentation
In order to decrease the fermentation time required to complete 300 g/L fructose utilization as reported in Example 2, fed-batch culture technique was used. The results of fed-batch culture with L. intermedius NRRL B-30560 and 300 g/L fructose is shown in FIG. 3 . The fermentation time decreased considerably from 136 h to 92 h by feeding equal amounts of substrate and medium four times. The yields of mannitol, lactic acid and acetic acid were 202.5±4.3, 52.6±1.0 and 38.5±0.7 g/L, respectively. The maximum cell growth (cell density, A 660 of 6.9±0.2) occurred in 64 h. The yields of mannitol, lactic acid and acetic acid from co-fermentation of fructose and glucose (2:1) at 300 g/L total substrate concentration in fed-batch fermentation were 179.4±9.3, 44.08±0.4 and 33.4±0.6 g, respectively in 160 h. The maximum cell growth (A 660 of 3.1±0.3) was observed at 88 h.
EXAMPLE 5
Production of Mannitol under Anaerobic Conditions
L. intermedius NRRL B-30560 was grown essentially as described in Example 2 in simplified MRS medium under anaerobic conditions using 2% fructose as the carbon source. The product patterns were analyzed by HPLC. The bacterium produced mannitol, lactic acid and acetic acid in product ratios similar to those obtained under aerobic conditions.
EXAMPLE 6
Comparative Microbiological Production of Mannitol
A comparative study of mannitol production by L. intermedius NRRL B-30560 with those of the earlier workers is presented in Table III. Fermentations were conducted as described in Example 2, except that the other bacteria reported in Table III were grown on enriched MRS medium (including beef extract and Tween) as described in Example 1. It is expected that the reported fermentation time for L. intermedius NRRL B-30560 could be shortened by using the enriched MRS medium.
EXAMPLE 7
Isolation of Mannitol Dehydrogenase from L. intermedius B-30560
The bacterium was grown in 1 L fleakers with a working volume of 700 ml at 37° C. and initial pH of 6.5 for 16 h using 15% fructose at which time mannitol dehydrogenase activity reached a maximum. The pH was controlled at 5.0 with 5 M NaOH. The cells were separated from the fermentation broth by centrifugation (15,000 g, 25 min) and washed with 50 mM phosphate buffer, pH 5.5. The washed cells were then suspended in the same buffer plus 1 mM Dithiothreitol (DTT) and treated with glass beads overnight. After centrifugation (30,000 g, 20 min), the clear supernatant was used as crude mannitol dehydrogenase (MDH) preparation. The enzyme was then subjected to DEAE-BioGel A column chromatography, BioGel A gel filtration, octyl-Sepharose column chromatography and finally Bio Gel HT column chromatography. The isolated mannitol dehydrogenase showed homogeneity as judged by native SDS-PAGE, SDS-PAGE and isoelectric gel electrophoresis. The first 20 N-terminal amino acids of purified mannitol dehydrogenase from L. intermedius B-30560 are Met-Lys-Ala-Leu-Val-Leu-Gln-Gly-Ile-Lys-Asp-Leu-Ala-Val-Gln-Asp-Tyr-Glu-Val-Pro (SEQ ID NO: 1). The purified enzyme was used for conversion of fructose to mannitol (see Example 8).
EXAMPLE 8
Biochemical Production of Mannitol
In a reaction mixture containing 1.4% fructose, 50 mM phosphate buffer, pH 5.0 and 0.2 mM NADPH or NADH, the purified enzyme obtained in Example 7 was fairly active over a pH range 4.5-8.5 and temperature up to 50° C. with optimum pH being 5.5 and optimum temperature at 35° C. The enzyme converted fructose to mannitol almost quantitatively within 6 h at pH 5.0 and 30° C. The enzyme did not show any activity towards conversion of xylose to xylitol and arabinose to arabitol.
TABLE I
Mannitol production from fructose by L. intermedius NRRL B-30560
in pH controlled batch fermentation. a
Fructose
Time
Mannitol
Lactic acid
Acetic acid
(g/L)
(h)
(g/g)
(g/g)
(g/g)
150
20
0.72 ± 0.00
0.17 ± 0.00
0.12 ± 0.00
200
40
0.69 ± 0.03
0.17 ± 0.00
0.13 ± 0.00
250
64
0.70 ± 0.02
0.16 ± 0.00
0.12 ± 0.00
300
136
0.66 ± 0.03
0.15 ± 0.01
0.11 ± 0.00
a At 37° C., 130 rpm, Initial pH 6.5, pH controlled at 5.0, 500 ml fleaker with 300 ml medium.
TABLE II
Mannitol production using two substrate system (fructose and
another sugar) by Lactobacillus intermedius NRRL B-30560 in
pH-controlled batch fermentation. a
Substrate
Time
Mannitol
Lactic acid
Acetic acid
(g/L)
(h)
(g/L)
(g/L)
(g/L)
Fructose (100)
20
97.3 ± 2.6
23.2 ± 0.5
15.8 ± 0.4
plus glucose (50)
Fructose (50)
64
84.5 ± 0.7
23.6 ± 1.6
13.6 ± 0.3
plus sucrose (100)
Fructose (100)
24
86.6 ± 1.2
25.7 ± 0.5
13.8 ± 0.1
plus starch (50)
and glucoamylase
Fructose (100)
15
95.9 ± 0.8
20.9 ± 0.2
14.2 ± 0.4
Plus maltose (50)
Fructose (100)
89
89.1 ± 1.9
18.4 ± 2.6
14.6 ± 1.9
plus mannose (50)
Fructose (100)
15
82.3 ± 0.7
16.7 ± 0.7
13.2 ± 0.2
plus galactose (50)
Fructose (100)
40
94.1 ± 0.7
24.8 ± 0.3
15.3 ± 0.1
plus raffinose (50)
Fructose (100)
64
61.6 ± 0.9
41.1 ± 1.1
27.3 ± 1.2
plus arabinose (50)
a At 37° C., except for starch at 30° C., initial pH 6.5, pH maintained at 5.0, 130 rpm, 500 ml fleaker with 300 ml medium.
TABLE III
Comparison of mannitol production by L. intermedius B-30560
with those of earlier workers
Substrate
Time a
Yield b
Microorganism
(g/L)
(h)
(%)
Reference
Bacteria
Lactobacillus
Fructose (150)
15
72
This work
intermedius B-30560
Fructose (200)
40
69
This work
Fructose (250)
64
70
This work
Fructose (300)
136
66
This work
Fructose (300)
926
67
This work (fed-batch)
Fructose (100) +
20
65
This work
Glucose (50)
Lactobacillus
Fructose (100) +
24
65
Itoh et al., 1991,
sp. B001
Glucose (50)
supra
Lactobacillus
Fructose (100)
120
73
Yun et al., 1998,
sp. Y-107
supra
Lactobacillus
Fructose (?)
120
60 g/L
Korakli at al., 2000,
sanfranciscensis
supra
Leuconostoc
Fructose (100) +
35
60
Soetart et al., 1995,
mesenteroides
Glucose (50)
35
60
supra
L. mesenteroides
Fructose (08)
—
30-40
Erten, 1998, Proc.
Biochem 33:735-739
Leuconostoc
Fructose (50)
25
40
Yun at al., 1998,
sp. Y-002
supra
Yeast
Candida magnoliae
Fructose (150)
168
45
Song at al., 2002
Biotechnol. Lett.
24:9-12
Torulopsis
Glucose (194)
240
28
Onishi at al., 1968
versalitis
Appl. Microbiol.
16:1847-1852
Torulopsis
Glycerol (100)
168
31
Onishi et al., 1970
mannitofaciens
Biotechnol. Bioeng.
12:913-920
Fungi
Aspergillus
Glucose (32)
288
69
Smiley et al., 1967
candidus
Biotechnol. Bioeng.
9:365-374
Candida
n-Paraffin (100)
100
52
Hattori et al., 1974
zeylannoides
Agri. Biol. Chem.
38:1203-1208
Penicillium
Sucrose (150)
288
40
Hendriksen et al.,
scabrosum
1988, J. Chem.
Techno. Biotechnol.
43:223-228
a Time to reach maximum mannitol yield.
b Mannitol yields were calculated on the basis of initial sugars employed.
|
Mannitol is produced in a highly efficient fermentative method using Lactobacillus intermedius NRRL B-30560, or in a biochemical method using mannitol dehydrogenase isolated from this strain. Fructose serves as the primary carbon substrate in both the fermentative and biochemical conversions, but important secondary carbon sources include glucose, maltose, mannose and galactose. Mannitol is useful in the food, pharmaceutical, and medicine industries as a sweet-tasting bodying and texturing agent.
| 2
|
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119(e) to provisional patent application serial No. 60/226,160 filed Aug. 16, 2000; the disclosure of which is incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] One option that is popular with motor vehicles is cruise control. Cruise control allows an operator of a motor vehicle to set a predetermined speed for the vehicle, and maintains the vehicle at that speed until either the cruise control is turned off, or the brakes are applied.
[0003] A motor vehicle typically has a speed sensor mounted on an output shaft of a transmission. The speed sensor provides a series of pulses to a computer. When a vehicle's speed increases the frequency of the pulses will also increase. There is a concomitant decrease in the frequency of the pulses from the speed sensor when the speed of the vehicle decreases. For a given vehicle speed, there is a correlated frequency of the pulse stream from the speed sensor. The cruise control attempts to maintain the pulse frequency of the desired speed by regulating the accelerator of the vehicle.
[0004] The cruise control stores the speed of the vehicle when the cruise control is set to the desired speed. The cruise control receives the pulse stream from the speed sensor and compares the frequency of the pulse stream to the frequency value of the set speed. The cruise control, in response to a difference between the pulse stream from the sensor and the stored set value operates a vacuum controlled diaphragm that is coupled to the accelerator linkage. The accelerator is controlled in order to maintain the pulse stream from the speed sensor as close to the stored value as possible.
[0005] It is common for a vehicle operator to use cruise control to maintain a constant speed on a highway. In the event another operator makes a lane change into the path of the vehicle or the vehicle comes upon a slower driver the operator is required to disable the cruise control, typically by stepping on the brake. A problem occurs when the operator is slow to react to the other vehicle and fails to disable the cruise control in time.
[0006] In view of the dangers associated with automobile travel, there is an ongoing need or the vehicle comes upon a slower driver the operator is required to disable the cruise control, typically by stepping on the brake. A problem occurs when the operator is slow to react to the other vehicle and fails to disable the cruise control in time.
[0007] In view of the dangers associated with automobile travel, there is an ongoing need for enhanced automobile driver aides. One possible area of increased driver aides involves detection of objects in front of a vehicle. As the vehicle approaches objects (e.g. other vehicles, pedestrians and obstacles) or as objects approach the vehicle a driver cannot always detect the object and perform intervention actions necessary to avoiding a collision with the object.
[0008] To enhance the safety of trucks, for example, sensor systems or more simply “sensors” for detecting objects around a truck have been suggested. Such sensors typically include an optical or infrared (IR) detector for detecting obstacles in the path of the vehicle.
[0009] In such an application, it is necessary to provide a sensor capable of accurately and reliability detecting objects in the path of the vehicle.
[0010] Radar is a suitable technology for implementing a sensor for use in vehicles such as automobiles and trucks. One type of radar suitable for this purpose is Frequency Modulated Continuous Wave (FMCW) radar. In typical FMCW radar, the frequency of the transmitted CW signal linearly increases from a first predetermined frequency to a second predetermined frequency. FMCW radar has the advantages of high sensitivity, relatively low transmitter power and good range resolution.
[0011] Because sensors disposed on vehicles are consumer products that may affect the safety of vehicles, the accuracy and reliability of the sensors are tantamount. Aspects of the sensors which contribute to its accuracy and reliability include its susceptibility to noise and the overall precision with which received radio frequency (RF) signals are processed to detect objects within the field of view of the sensor. Susceptibility to noise for example can cause false detections and, even more deleteriously, cause an object to go undetected.
[0012] Further significant attributes of the sensors are related to its physical size and form factor. Preferably, the sensor is housed in a relatively small enclosure or housing mountable behind a surface of the vehicle. For accuracy and reliability, it is imperative that the transmit antenna and receive antenna and circuitry of the sensor are unaffected by attributes of the vehicle (e.g. the vehicle grill, bumper or the like) and that the sensors are mounted to the vehicle in a predictable alignment.
[0013] It would, therefore, be desirable to provide a sensor system which is capable of detecting the presence of objects in front of a vehicle and further to detect the speed of these objects. Once this information is obtained the speed of the vehicle can be adjusted to maintain a safe trailing distance behind an object located in front of the vehicle.
BRIEF SUMMARY OF THE INVENTION
[0014] In accordance with the present invention, a detection system is utilized to control the speed of a vehicle, known as Adaptive Cruise Control. The system includes a radio frequency (RF) transmit receive (TR) sensor module (or more simply “sensor”) disposed such that a detection zone is deployed in front of a vehicle. The sensor includes a sensor antenna system which comprises a transmit antenna for emitting or transmitting an RF signal and a receive antenna for receiving portions of the transmitted RF signal which are intercepted by one or more objects within a field of view of the transmit antenna and reflected back toward the receive antenna. A signal antenna can be used for both the transmitting and receiving.
[0015] With this particular arrangement, a detection system that detects objects in a region about a front of a vehicle is provided. If the system determines that the vehicle is approaching an object or that an object is approaching the vehicle, then the sensor initiates steps that are carried out in accordance with a set of rules that control the speed of the vehicle. The speed of the vehicle is adjusted to maintain a safe trailing distance behind the detected object, thereby providing an adaptive cruise control function to the vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The foregoing features of this invention, as well as the invention itself, may be more fully understood from the following description of the drawings in which:
[0017] [0017]FIG. 1 is a diagram showing a lead vehicle and a trailing vehicle equipped with the present invention;
[0018] [0018]FIG. 2 is a flow chart of the presently disclosed method;
[0019] [0019]FIG. 3 is a diagram of vehicle equipped with a near object detection (NOD) system including the forward looking remote sensor (FLRS) present invention; and
[0020] [0020]FIG. 4 is a block diagram of the FLRS of FIG. 3 that includes the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Referring now to FIG. 1, a vehicle 10 is shown having a zone of coverage 20 for performing adaptive cruise control. Vehicle 10 is shown as an automobile, however the presently disclosed invention could be used with any other type of vehicle such as a motorcycle, truck, aircraft, marine vehicle, agricultural vehicle or the like.
[0022] The adaptive cruise control zone of coverage 20 is provided by a forward looking sensor 25 described in U.S. Pat. No. 5,929,802 assigned to the assignee of the present invention and incorporated herein by reference. The forward-looking sensor is part of an RF detection system that utilizes an antenna system that provides multiple beams in the coverage zone. In this manner, the particular direction in which another object approaching the vehicle or vice-versa can be found. In one particular embodiment, the sensor utilizes an antenna system that includes eight separate antenna beams. Therefore, the RF system can operate in a manner similar to that described in the above-referenced U.S. Pat. No. 5,929,802.
[0023] The sensor utilizes Frequency Modulated Continuous Wave radar which transmits a linear FM signal which is reflected from objects within the radar's zone of coverage. The reflected signal is compared (mixed) with the transmit signal to determine the round trip travel time of the reflected signal via a frequency difference. This frequency difference is known as the IF signal. The frequency of the IF signal is proportional to the range of the object. The FMCW radar can detect stationary objects as well as objects with no motion relative to the originating vehicle (e.g. another vehicle traveling at the same speed).
[0024] As shown in FIG. 1 a first vehicle 10 is equipped with a detection system that is coupled to the accelerator of the vehicle. The detection system includes a transmit antenna, a receive antenna, a receiver circuit and an interface to control the accelerator of the first vehicle. The sensor provides a zone of coverage 30 . The transmit antenna of the sensor provides a Frequency Modulated Continuos Wave (FMCW) radar which transmits an FM signal providing the zone of coverage 30 . Vehicle 10 is referred to as a trailing vehicle. When trailing vehicle 10 encounters a lead vehicle 20 , the FM signal provided by the transmit antenna is reflected by the lead vehicle back to the sensor of trailing vehicle 10 . The reflected signal is received by the receive antenna and is compared with the transmit signal. The frequency difference between the transmit signal and the received signal is proportional to the distance between the lead vehicle and the trailing vehicle. By providing continuos signals, the speed of the lead vehicle with respect to the trailing vehicle can be determined from repeated measurements of the reflected signals.
[0025] A well-known safety rule is the so-called “three second” rule. The three second rule states that a safe distance between a lead vehicle and a trailing vehicle is the distance that can be covered in three seconds traveling at the speed of the lead vehicle. This distance translates to approximately 198 feet at 45 miles per hour, 242 feet at 55 miles per hour and 286 feet at 65 miles per hour.
[0026] In a particular embodiment the three-second rule is used to determine a travel distance, though other rule sets could also be used. This travel distance provides a base line distance, but to provide a larger degree of safety, the travel distance is modified to take into account the weight of the trailing vehicle. When the trailing vehicle is large, it will take more time to stop than a lighter vehicle, therefore the travel distance is modified according to the weight of the trailing vehicle to provide a safe trailing distance.
[0027] With the safe trailing distance determined, the sensor adjusts the accelerator of the trailing vehicle to keep the safe trailing distance maintained between itself and the lead vehicle. This is done automatically and dynamically, so that the driver input is reduced or removed. For example, if the trailing vehicle were traveling on a highway and has it's cruise control set at 65 miles per hour, and a vehicle changes lanes in front of the driver, the accelerator is dynamically controlled to permit a safe traveling distance between the trailing vehicle and the lead vehicle. Similarly, if a slower moving vehicle is encountered, the accelerator is controlled such that the faster moving trailing vehicle does not overcome the safe trailing distance.
[0028] Referring now to FIG. 2 a flow chart of the presently disclosed method is shown. An initial step 110 of the method involves inputting the weight of the vehicle which is equipped with the sensor (the trailing vehicle). The weight of the vehicle is used later to aid in establishing a desired trailing distance between the trailing vehicle and a lead vehicle. This step is only done initially, but can be modified if the system is installed on a different vehicle or if the vehicle is towing something.
[0029] The next step 120 is to determine the speed of the lead object. As described above, the sensor utilizes a FMCW signal to determine the presence and relative speed of an object located within the zone of coverage of the sensor. The sensor will detect objects that have the same speed as the trailing vehicle, as well as objects that are completely stopped.
[0030] Once the presence and relative speed of a lead vehicle has been determined, the safe trailing distance is calculated, as recited in step 130 . The trailing distance can be determined in a number of ways, such as by using the three-second rule or other rule sets which relate a trailing distance to a speed of a vehicle. The trailing distance determination may also take into account the weight of the trailing vehicle or any other characteristics that would have an impact on determining a safe trailing distance.
[0031] The next step is to dynamically adjust the accelerator of the trailing vehicle to maintain the desired safe trailing distance between the lead vehicle and the trailing vehicle. This is shown in step 140 . The system is dynamic, in that the transmitting and receiving of the signals are continuous, as is the determining of a safe trailing distance and the maintaining of the safe trailing distance.
[0032] While the forward looking sensor used to provide the adaptive cruise control function can operate independently, the system may also be included as part of a near-object detection system (NODS). Referring now to FIG. 3 and FIG. 4, a near-object detection (NOD) system 210 is disposed on a vehicle 10 which is here shown in phantom since it is not properly a part of the NOD system 210 . In this particular embodiment, the near-object detection system 210 includes a forward-looking sensor (FLS) 216 described above, an EOS sensor 218 , a plurality of side-looking sensor (SLS) systems 220 and a plurality of rear-looking sensor (RLS) systems 222 . Each of the FLS, EOS, SLS, and RLS systems is coupled to a sensor processor 214 .
[0033] In this particular embodiment, the sensor processor 214 is shown as a central processor to which each of the FLS, EOS, SLS, and RLS sensors may be coupled via a bus or other means. It should be appreciated that in an alternate embodiment, one or more of the FLS, EOS, SLS, and RLS sensors may include its own processors to perform the processing described below. In this case, the near-object detection system would be provided as a distributed processor system.
[0034] Regardless of whether the near-object detection system includes a single or multiple processors, the information collected by each of the sensors is shared and the processor (or processors in the case of a distributed system) implement a decision or rule tree. For example the sensor processor is coupled to the airbag system 224 , the adaptive cruise control interface 226 , and the braking system 228 of the vehicle. In response to signals from one or more of the FLS, EOS, SLS, and RLS systems, the sensor processor may determine that it is appropriate to “pre-arm” the airbag of the vehicle, adjust the accelerator, or engage the braking system. Other examples are also possible.
[0035] For example, the NOD system 10 may be used for a number of functions including bit not limited to blind spot detection, lane change detection, pre-arming of vehicle air bags and to perform a lane stay function, and the above-mentioned pre-arm airbag function.
[0036] It should be appreciated that the sensors may be removably deployed on the vehicle. That is, in some embodiments the sensors may be disposed external to the body of the vehicle (i.e. disposed on an exposed surface of the vehicle body), while in other systems the sensors may be embedded into bumpers or other portions of vehicle (e.g. doors, panels, quarter panels, and vehicle front ends, and vehicle rear ends). Its is also possible to provide a system which is both mounted inside the vehicle (e.g., in the bumper or other location) and which is also removable.
[0037] Since the characteristics of a single sensor can be changed to allow the sensor to provide detection capabilities in coverage zones of different sizes and shapes, the sensor can also be used on a vehicle that is larger or smaller than the vehicle as shown in FIG. 3. Thus, modification of a coverage zone provided by a particular sensor can be accomplished by programming the sensor and in particular by adjusting the range gates of the sensor.
[0038] In one embodiment, using a reconfigurable antenna changes the coverage zone. In one embodiment, the reconfigurable antenna is provided by using microelectromechanical (MEMs) devices that are used to change beam shape and thus beam coverage. The MEMS can change the aperture shape and thus the shape of the beam.
[0039] The sensor can be updated. In one particular embodiment, a vehicle owner brings the vehicle to a dealership or other upgrade station and the upgrade station downloads a software upgrade to a programming station. The upgrade may be downloaded from the software upgrade area to the upgrade station via a secure wireless local area network (LAN) or a CDROM mailed to the upgrade station or any other means for transmitting software between two points as is known to those of ordinary skill in the art. Once the upgrade station has the desired software upgrade, a vehicle owner brings the vehicle to the software upgrade station and the upgrade software is transmitted to the vehicle, thereby upgrading software in each of the sensors. In an alternate system, the software upgrade is fed via a satellite system and then transmitted directly from the satellite system to the vehicle. Using either technique, the software operating in the sensors and/or the sensor processor can be modified.
[0040] Having described the preferred embodiments of the invention, it will now become apparent to one of ordinary skill in the art that other embodiments incorporating their concepts may be used. It is felt therefore that these embodiments should not be limited to disclosed embodiments but rather should be limited only by the spirit and scope of the appended claims. All publications and references cited herein are expressly incorporated herein by reference in their entirety.
|
In accordance with the present invention, an adaptive cruise control system includes a radio frequency (RF) transmit receive (TR) sensor module (or more simply “sensor”) disposed such that a detection zone is deployed in front of a vehicle. The sensor includes a sensor antenna system which comprises a transmit antenna for emitting or transmitting an RF signal and a receive antenna for receiving portions of the transmitted RF signal which are intercepted by one or more objects within a field of view of the transmit antenna and reflected back toward the receive antenna. With this particular arrangement, a detection system that detects objects in a region about a front of a vehicle is provided. If the system determines that the vehicle is approaching an object or that an object is approaching the vehicle, then the sensor initiates steps that are carried out in accordance with a set of rules that control an accelerator of the vehicle. The accelerator is adjusted to maintain a safe trailing distance behind the detected object.
| 7
|
REFERENCE TO PRIOR APPLICATIONS
[0001] This is a continuation application from Ser. No. 10/458,393, filed Jun. 10, 2003 which is a divisional application from Ser. No. 08/888,630, filed Jun. 21, 2001, which is a divisional application from Ser. No. 09/360,372, filed Apr. 28, 1999, Pat. No. 6,550,201, which is a continuation of application Ser. No. 08/716,507, filed Sep. 17, 1996, Pat. No. 5,953,874 which is a continuation of application Ser. No. 08/364,659, filed Dec. 27, 1994 (abandoned), which is a continuation of Ser. No. 07/976,611, filed Nov. 16, 1992, Pat. No. 5,392,575, which is a continuation of Ser. No. 07/745,995, filed Aug. 9, 1991 (abandoned), which is a continuation of Ser. No. 07/292,742, filed Jan. 3, 1989 (abandoned), and a continuation of Ser. No. 07/763,870, filed Sep. 19, 1991, which is a continuation of application Ser. No. 07/507,002, filed Apr. 10, 1990 (abandoned), which is a continuation of application Ser. No. 07/319,852, filed Mar. 3, 1989 (abandoned), which is a continuation of application Ser. No. 07/101,832, filed Sep. 28, 1987 (abandoned), which is a continuation-in-part of application Ser. No. 06/926,291, filed Nov. 3, 1986, Pat. No. 4,724,642.
BACKGROUND OF THE INVENTION
[0002] This invention relates to outdoor residential constructions, and is particularly concerned with support devices for use in deck construction.
[0003] Various types of devices have heretofore been used for supporting and/or connecting building elements, such as horizontal beams, joists, stringers, posts and pillars, to a base slab, footing, foundation or block member. For example, such devices include anchor studs, metal brackets, or other supports or devices which are permanently embedded in the concrete in the manufacturing process of the blocks and which are required to make them functional. Such devices or additional components are used to provide vertical and lateral mechanical connection of building elements to a base or as components to other elements but do not have an individual identity or non-mechanical application which facilitates the inexpensive and convenient construction of a simple deck, such as a deck that may be built by the average home owner on unprepared and unleveled ground typical to a residential backyard.
SUMMARY OF THE INVENTION
[0004] According to the present invention and forming a primary objective thereof, a deck construction is provided including a novel construction support device, which amounts to an improvement over prior structures.
[0005] A more particular object of the invention is to provide a construction support device of the type described having a novel arrangement of recesses, walls, and sockets for receiving horizontal beams and the like, and also capable of receiving vertical pillars or posts, all in a variety of selected support connections not heretofore available.
[0006] Another object of the invention is to provide an embodiment of the invention comprising a plurality of integrated wall portions disposed in a zig zag pattern and forming one or more full width slots for receiving horizontal beams and the like and also forming a rectangular central socket for receiving a vertical pillar or post.
[0007] Another object of the invention is to provide a pier block of the type described having a novel arrangement of recesses and central socket for receiving horizontal two-inch thick (1½-inch nominal) surface supports, and also capable of receiving vertical wood posts without mechanical connections or additional components, all in a variety of selected support configurations not heretofore available.
[0008] In carrying out these objectives, a construction support device is provided for anchoring a beam or other element to the ground or other building site. The device includes a body having upper and lower portions. The lower portion rests on the building site, and the upper portion includes an open slot for holding a beam edgewise. The slot is formed by spaced-apart side walls. The side walls themselves include connected wall portions, which are integrally joined at right angles.
[0009] The slot includes a center socket portion that is adapted for securely holding the bottom end of a vertically oriented post. The center socket portion is formed by the side walls extending at right angles away from each other to form corner sections. The corner sections are spaces apart substantially further than the width of the open slot to provide substantial corner support to the post.
[0010] In some cases, the side walls which define the slot are part of spaced-apart projections which extend from the upper portion of the body. These projections can be integrally molded with the body to form a single-cast, one-piece block or pier. Alternatively, they may be formed of plastic or metal and suitably attached to a base.
[0011] The invention may be practiced with a pair of recesses emanating from the central socket portion to form a single slot which extends unobstructed across the entire breadth of the body. Alternatively, a second pair of recesses may be employed to form a total of two mutually perpendicular slots.
[0012] Support devices in accordance with the invention are particularly suited to the construction of residential decks. Horizontal, coplanar deck support members may be carried by a plurality of the foregoing support devices arranged in rows and columns. The horizontal deck support members are securely seated in the slots defined by the spaced apart side walls.
[0013] Where the deck is to be built on uneven ground, the horizontal members can be supported in a level attitude by a plurality of vertical support pillars. The bottom ends of the vertical support pillars are securely seated in one of the center socket portion, while their respective top ends bear the horizontal members in supporting engagement. The height of the vertical support pillars can vary to span the vertical distance between the uneven ground and the desired plane in which the horizontal support members reside.
[0014] In one embodiment, the construction support device of the invention comprises a body member having a lower surface which serves as a support on a base such as a slab, footing, or pier block. The body member has one or more recess means arranged to receive horizontal beams and the like. The body member also has a central socket for receiving a vertical pillar or post. The recess means are disposed on each of four sides of the body member at 90 degrees apart and communicate with the central socket and the exterior, the pairs of recesses opposite from each other being aligned whereby construction beams or the like can be laid therein in edge and/or end relation. Also, in such embodiment, the construction device has fastener-receiving means therein for attaching a beam or beams and a pillar together, and also for attaching the assembly to the base. In another embodiment, side edges of the body member at the recess openings have downturned projections shaped on a rear portion thereof to frictionally fit on top of pier blocks for anchoring the body member against lateral shifting.
[0015] In another embodiment, the construction support device of the invention is a single cast, one-piece pier block which comprises a body member serving as a capable support on unprepared and unleveled building sites, having localized dips, slopes and random level areas therein. The body member has a single recess means molded into the top surface capable of receiving horizontal deck surface support members and also capable of receiving the bottom end of a vertical wood post or pillar. The recess means can have particular dimensions for using conventional, existing lumber sizes and also such dimensions are such that the required integral strength of the block is maintained due to the manufacturing process and application without the necessity of using reinforcing bar steel or additional integral components. All of these features combine in a structural arrangement which automates and standardizes the manufacture and facilitates marketing, at a lower unit and resale cost, a deck that can be preplanned and pre-cut. Such a deck is simplified and inexpensive, and capable of construction by the average do-it-yourself homeowner who desires a deck on the unprepared and unleveled ground of a typical backyard.
[0016] The invention will be better understood and additional objects and advantages will become apparent from the following description taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a top perspective view of a support device in accordance with a first embodiment of the invention;
[0018] FIG. 2 is a bottom perspective view of the device shown in FIG. 1 ;
[0019] FIG. 3 is a bottom perspective view of a construction support device in accordance with another embodiment of the invention;
[0020] FIG. 4 is a bottom perspective view of a construction support device in accordance with yet another embodiment of the invention;
[0021] FIGS. 5, 6 , 7 and 8 are perspective views showing various applications of the device of FIG. 1 in association with structural building elements;
[0022] FIG. 9 is a perspective view of a construction support device which includes lateral stabilizing elements in accordance with another embodiment of the invention;
[0023] FIG. 10 is a bottom perspective view of the construction support device of FIG. 9 ;
[0024] FIGS. 11 and 12 are perspective views showing various applications of the device of FIG. 9 in association with structural building elements;
[0025] FIG. 13 is a perspective view of a construction support device in accordance with another embodiment of the invention;
[0026] FIG. 14 is a bottom perspective view of the construction support device shown in FIG. 13 ;
[0027] FIG. 15 is a top perspective view of the construction support device shown in FIG. 13 ;
[0028] FIG. 16 is a top plan view of the construction support device shown in FIG. 13 ;
[0029] FIG. 17 is a perspective view of a construction support device in accordance with another embodiment of the invention;
[0030] FIG. 18 is a top perspective view of the construction support device shown in FIG. 17 ;
[0031] FIG. 19 is a top plan view of the construction support device show in FIG. 17 ;
[0032] FIGS. 20 and 21 are perspective views showing various applications of the device of FIG. 17 in association with structural building elements;
[0033] FIG. 22 is a perspective view of a deck construction in accordance with the invention employing the construction support device shown in FIG. 17 ; and
[0034] FIG. 23 is a perspective view of another deck construction in accordance with the invention employing the construction support device shown in FIG. 17 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0035] According to the present invention, a construction support device is provided which conveniently provides anchoring of a building element to a building site. As illustrated herein, the invention may be practiced in accordance with a first embodiment of FIG. 1 , wherein the construction support device is securely attached to a concrete base or pier. The device of FIG. 1 can be inexpensively molded from plastic or stamped from metal and is simplified in its use and constructions.
[0036] Alternatively, the invention may be practiced in accordance with other embodiments, such as shown in FIGS. 13 and 17 . There, the device is inexpensively poured from concrete together with a pier block to form a single cast, one-piece body. In either type of embodiment, the invention provides a new and advantageous support for securely seating construction members in either a horizontal or vertical orientation.
[0037] With reference first to FIGS. 5 through 8 , the numeral 10 represents a base or pier block of conventional structure which is commonly used to support decks, carports, etc. This block is generally constructed of concrete and assumes different shapes. In most cases, the block is tapered to a lesser dimension toward the top. The top and bottom surfaces 12 and 13 , respectively, are flat.
[0038] FIGS. 1-8 illustrate a construction support device 14 in accordance with a first embodiment of the invention. Construction support device 14 may be molded, stamped, or otherwise formed from a tough plastic or metal. The body member of the device 14 includes a flat bottom wall 16 and four identically shaped or symmetrical upright quarter sections 18 . Each of the sections 18 comprises four zig zag panels 18 a joined integrally at right angles. These symmetrical quarter sections are shaped to form a recess or opening 20 on each side, with oppositely located recesses being laterally aligned. Also, with this quarter section construction, a square central socket 22 is formed. Laterally aligned recesses 20 provide a pair of full width slots open at the sides.
[0039] Each of the panel sections 18 a has one or more apertures 24 therein provided to receive fasteners, to be seen hereinafter, for securement of building elements to the device 14 . As seen in FIG. 2 , cutouts 26 are provided in the bottom wall 16 for reducing the weight of the member as well as for conserving material. Also, apertures 28 are provided in the wall 16 for secured attachment of the member 14 to a base, such as to a block 10 , a concrete slab, or other support means.
[0040] FIGS. 5, 6 , 7 and 8 show various applications of the construction device 14 with building elements such as support members and pillars. FIG. 5 for example shows a horizontal decking surface support member 30 seated edgewise on the bottom wall 16 and extending fully through the device and out both side recesses 20 . FIG. 6 shows a support member 30 similarly supported as in FIG. 5 but also showing a right angle support member 32 extending through a 90 degree side recess 20 and abutted against the support member 30 . FIG. 7 shows a vertical pillar 34 supported ion the device 14 and fitted in the central socket 22 . FIG. 8 shows a pillar 34 similarly fitted in the socket 22 as in FIG. 7 but also showing side beams 32 extending in from all four of the side recesses. These members may simply be fitted in the respective recesses 20 or socket 22 . Preferably, however, secured attachment to the member 14 is accomplished by fasteners 36 extending through the apertures 24 . Also, device 14 can first be secured to the base member 10 by fasteners extending through the apertures 28 .
[0041] FIG. 3 is a bottom perspective view of a construction device 14 ′ having a bottom wall 16 and side walls 18 in an arrangement similar to that shown in FIGS. 1 and 2 . This structure, however, is formed (such as by integral molding) with a plurality of depending foot member 38 . Four of such foot members are shown, as well as a central foot member, but any number of such foot members maybe provided. In the FIG. 3 embodiment, the foot members 38 are hollow whereby long fasteners can be inserted down from the top through the wall 16 and into a base for secured attachment of the construction device 14 ′ to the base. FIG. 4 shows a structure similar to FIG. 3 except that the outer foot members 38 ′ are solid and not hollow. This embodiment may be employed in circumstances where it is not necessary to use vertical fasteners around an outer portion of the member.
[0042] FIGS. 9-12 illustrate an embodiment of the invention employing means for anchoring the body member against lateral shifting. In this embodiment, the body member 14 ″ is the same as that shown in FIG. 1 with respect to quarter panel sections 18 a and their formation of aligned recesses 20 and central socket 22 . To accomplish the lateral anchoring feature, the outermost panel section 18 a of each quarter section has a depending projection or lip 40 defined by a bottom wall portion 42 integral with side extensions 44 and a rear wall portion 46 . Rear wall portion 46 preferably angles outwardly toward the bottom to coincide with the angle of the side surfaces of pier block 10 . Rear wall portion 46 can extend at a desired angle, so as to have flush engagement with pier block sides or varying shape.
[0043] FIGS. 11 and 12 show application of the device 14 ″ of FIG. 9 to a pier block. In such arrangement, the device 14 ″ and the building elements therein are anchored or locked against lateral shifting. Fasteners extending through the bottom wall of the device are not necessary, although such fasteners can be used if desired. The cross dimension of the device between rear wall portions 46 can be preselected according to the size of the pier block so that a snug or frictional fit is provided.
[0044] Referring to FIGS. 13-21 , it will be seen that the device 14 may be made of concrete and integrally molded into the upper surface 12 ′ of a pier block such as pier block 50 . As shown in FIGS. 13-16 , the four upright quarter sections 18 ′ include zig-zag walls 18 a ′ which project from flat bottom wall 16 ′. Recesses 20 ′ define two perpendicular slot portions extending across the full width of upper surface 12 ′. Zig-zag walls 18 a ′ also define the four comers of a square central socket 22 ′.
[0045] With reference to FIGS. 17-21 , the concept of the invention can also utilize a pier block 50 ′ having a central socket portion 22 ′ and only two equal narrower recesses 20 ′ which extend inward from outer edges of two opposite sides of the top surface of the block 50 ′ and lead into the central socket portion, as best shown in FIG. 18 . The two narrower recesses 20 ′ form but a single slot for receiving a horizontal decking surface support member 30 which also passes through the central socket portion 22 ′, as shown in FIG. 20 . The central socket portion 22 ′ is for receiving vertical pillar supports 34 , independent of the two equal narrower recesses 20 ′, as shown by FIG. 21 . The horizontal decking surface support members 30 and vertical pillar support members 34 being mutually exclusive to each other in the recess of block 50 ′ and also mutually interchangeable with each other in the same recess of the same block 50 ′.
[0046] The combination of slots and sockets allows a support in accordance with the invention to accommodate both vertical and horizontal beams, and is particularly well-suited for constructing decks on unprepared and unleveled building sites, two examples of those being shown in FIGS. 22 and 23 . Such decks, by using the present block, are extremely simplified in their construction and can be supplied in pre-planned, pre-cut units. Other advantages also exist in the structure, as will be apparent hereinafter.
[0047] The deck shown in FIG. 22 , designated by reference numeral 52 , comprises the pier blocks 50 ′ as the base or ground support for the deck and can have such lumber as two-inch thick (1½ inch thick nominal) horizontal decking surface support member 30 received by the two equal narrower portions 20 ′, also passing through the central socket portion 22 ′ when the vertical pillar support 34 is not in the block 50 ′, those members 30 then supporting the deck surface structure 54 which is nailed in place and those blocks 50 ′ directly receiving member 30 being on localized high or level ground within an unprepared and unleveled building site.
[0048] The deck shown in FIG. 23 , designated by the numeral 56 , similarly uses some pier blocks 50 ′ as described above and also illustrates the use of some blocks 50 ′ as the base or ground support for vertical pillar supports 34 set in the central socket 22 ′ when the member 30 is not in block 50 , member 34 then providing support to member 30 when member 30 is not directly received by block 50 due to localized variations of the ground within an unprepared and unleveled building site. A deck support member 30 can also be fastened to a building 60 , as shown in FIG. 23 .
[0049] The particular structure of the manufactured pier blocks 50 and 50 ′ makes it possible to construct an extremely simplified deck and one which can be pre-planned and pre-cut if desired. That is, such lumber as 2-inch thick deck support members 30 and vertical wood pillars 34 which can be used therewith comprise conventional existing material, namely, the two-inch thick deck support number 30 can comprise 2×6s or 2×4's and pillars 34 can comprise 4×4's.
[0050] The two equal narrower recesses 20 ′ can be 2 inches deep and have a width of 1¾ inches. This latter dimension would receive conventional finished 2×6's (1½ inches thick) and 2×4's (also 1½ inches thick). 2×6's and 2×4's have finished height dimensions of 5½ and 3½ inches, respectively, whereby the deck support members, whether 2×6's or 2×4's, project to a minimum necessary height above the top surface of the blocks 50 when seated in the recess for supporting the decking thereon.
[0051] The central socket portion 22 ′ can be 2 inches deep, similar to the recess portion 20 ′. Such socket is square, and can have dimensions of 3¾ inches for receiving a conventional finished 4×4 (3½ inches square) lumber support pillar. The vertical pillar becomes sufficiently fixed in socket portion 22 ′ in the block for deck construction purposes, as does the deck horizontal support member in the two narrower portions 20 ′, also being within the central socket portion 22 ′ when the member 34 is not in the block 50 , for lateral stability.
[0052] Pier blocks 50 and 50 ′ are designed to provide support to a deck on unleveled or unprepared building sites with no additional components required. For this purpose, the blocks 50 and 50 ′ are tapered to a larger dimension toward the bottom. The top and bottom surfaces are flat and square. The enlarged bottom surface allows the block to serve as its own footing. When two of such recesses 20 ′ are provided, they are standardly aligned across the block. Furthermore, the width of these recesses is less than one-third the width of the block at the top, thus maintaining lateral integral strength of the block. This arrangement maintains a strong concrete block without the necessity of re-bar reinforcement and thus contributes to manufacture of a pier block and deck structure in a pre-planned and pre-cut unit which is also sufficiently simplified in its use, standardized in its manufacture, and sufficiently inexpensive for deck construction by the average do-it-yourself homeowner.
[0053] Since the recess can be two inches deep, the recesses of the pier blocks 50 and 50 ′ of FIGS. 13 and 17 automatically and non-mechanically center the horizontal decking surface support member 30 and vertical pillars 34 in the pier block ( FIGS. 20 and 21 ) and automates connection and securement of these support members to the pier block for deck constructions 52 and 54 shown in FIGS. 22 and 23 . Mounted engagement of the horizontal surface support members and vertical pillars with the block is accomplished without metal-brackets or embedded connectors thus allowing individual blocks of a deck construction on unleveled and unprepared building sites to be adjusted without the need of any disassembly of the deck (i.e. removing bolts, nails or screws). Also, the recess of the pier blocks 50 and 50 ′ maintains horizontal and vertical members in parallel which is critical in construction of the deck.
[0054] It is to be understood that the forms of our invention herein shown and described are to be taken as preferred examples of the same and that other changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of our invention or the scope of the following claims.
|
A deck construction including a plurality of supports for anchoring deck construction elements to a building site. The supports include a body (which may be an integrally molded concrete pier) having upper and lower portions. The upper portion includes at least one slot for seating a horizontally oriented construction member. The slot includes a center socket portion having four extended comers for seating the bottom end of a vertically oriented construction member. The slot and center socket are defined by connecting wall portions which may be integral to the body or may be of plastic or metal and suitable secured to the body. In some cases, two mutually perpendicular slots are provided.
| 4
|
This application is a continuation-in-part of application Ser. No. 383,481, filed June 1, 1982, by the same applicant and having the same title, and now abandoned.
BACKGROUND OF THE DISCLOSURE
Most blade stabilizers used in the drilling of petroleum wells are of fixed design, not subject to being controlled from the surface of the well. Stabilizers are incorporated into the drill string, and serve to centralize the drill string in the well hole and to stabilize it against motions away from the well hole axis. The stabilizers are usually placed in the drill string at some depth well below the surface, it being necessary to withdraw the drill string from the well hole to install or relocate the stabilizers. This invention seeks to provide stabilizer apparatus which may be run into a well as part of the drill string and expanded and/or retracted at will to perform the stabilizer function as desired at a later time, and which may be repeatedly expanded and retracted as often as may be desired.
The surface controlled blade stabilizers afforded by this invention have a fully open flow passage therethrough, not restricted as is the case with the surface controlled blade stabilizers disclosed in application Ser. No. 368,996, filed Apr. 16, 1982, by the same applicant.
SUMMARY OF THE INVENTION
The stabilizers afforded by this invention have three or more radially movable stabilizer blades, which are disposed in slots of a lower body member of the apparatus. An expander mechanism interior of the blades is moved axially of the apparatus in one direction to cause expansion of the blades, and is moved in the opposite direction to permit retraction of the blades. The expander mechanism is controlled by control of fluid pressures interior of the apparatus, which may be controlled from the surface. Unlike the stabilizers disclosed in Application Ser. No. 368,996, filed Apr. 16, 1982, the stabilizer apparatus according to this invention has a full open flow passage therethrough, which is at no time closed or even partially closed. The apparatus may be operated by increased internal pressure to expand the stabilizer blades, and the internal apparatus pressure may be reduced while the blades are maintained in their outward positions. By variations of the fluid pressure within the apparatus, the stabilizer blades may also be retracted. These operations may be repeated as often as desired.
A principal object of the invention is to provide a drill string stabilizer apparatus which may be controlled from the surface. Another object of the invention is to provide such an apparatus having blades which may be expanded and retracted by alteration of internal drill string pressures. Another object of the invention is to provide such apparatus wherein control of the apparatus is achieved through changes in drill string pressure controlled entirely at the surface. Yet another object of the invention is to provide such apparatus wherein downward movement of an expander member causes stabilizer blade expansion, and upward movement of said member causes stabilizer blade retraction. A still further object of the invention is to provide such an apparatus having a full open fluid flow passage therethrough maintained fully open regardless of the expansion and retraction of the stabilizer blades. A further object of the invention is to provide such apparatus which is dependable, economical, and easily operated.
Other objects and advantages of the invention will appear from the following detailed description of a preferred embodiment, reference being made to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1A-1E are axial cross sectional views of a preferred form of apparatus according to the invention showing successive length portions of the apparatus from top to bottom.
FIG. 2 is a transverse horizontal cross section taken at line 2--2 of FIG. 1D.
FIG. 3 is a schematic diagram illustrating the form of a barrel cam employed in the preferred embodiment of apparatus according to the invention.
FIG. 4 is a transverse horizontal cross section taken at line 4--4 of FIG. 1D.
FIGS. 1F, 1G, 1H, and 1J are axial cross sectional views showing a modified form for the lower portion of the apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now first to FIGS. 1A-1E of the drawings, the apparatus includes an upper tubular body member 10, of circular horizontal cross sections, having a bore 11 downwardly therethrough and having an internally threaded socket 12 at the upper end of bore 11 by means of which the apparatus may be connected to the lower end of an upper drill string portion. The upper drill string portion to which the apparatus is connected at socket 12 will usually extend to the surface, the internal drill string pressure may be controlled therein by suitable pumps or other facilities at the surface (not shown). The surface equipment for this purpose is conventional, and further explanation thereof is not necessary. An upper sleeve 13 is disposed within body member 10 between upwardly facing interior shoulder 14 thereof and a Spiralox snap ring 15. Sleeve 13 is outwardly relieved below its upper end at 16 to provide an annular space 16a therearound within body member 10. A port 17, enlarged at its upper end, houses a check valve 18 and a plug 19 both screwed into threads around the enlarged portion of port 17. The port 17 is reduced at its lower end 20 and turns outwardly at 21, to communicate with the space 16a formed by relief 16. Piston sleeve 24, spaced uniformly inwardly from sleeve 13, has upper outwardly projecting portion 25 around which an O-ring 26 and wiper ring 27 are disposed in suitable grooves. A lower accumulator end ring 28 having O-ring seal 29 in a groove therearound is screwed into bore 11 of body member 10 at threaded connection 30. O-ring seal 31 seals end ring 28 to the lower exterior of sleeve 24. The annular space above end member 28, between sleeve 24 and body member 10 and between sleeve 24 and sleeve 13, forms an annular accumulator space 32 into which a pressured fluid, such as nitrogen gas, is injected through check valve 18 when plug 19 has been removed, the accumulator charging being done while the apparatus is at the surface before it has been connected into the drill string.
A tubular cam body 35 is disposed around the interior of body member 10 below accumulator end ring 28. An O-ring seal 36 seals between cam body 35 and the lower end of sleeve 24. Cam body 35 is of uniform wall thickness down to downwardly facing shoulder 38 and it is relieved outwardly therebelow to provide a space for a helical compression spring 39. Spring 39 bears/at its upper end against shoulder 38, and bears at its lower end against an upwardly facing shoulder 40 formed at the lower interior of upper body member 10. Spring 39, being under compression, biases cam element 35 upwardly. Cam body 35 has a barrel cam 42 machined around its outer surface, the form of the barrel cam being shown in FIG. 3 of the drawings. A lower body member 45 is connected at threaded connection 46 to the lower end of upper body member 10. Body member 45 has three vertical circularly spaced slots 48 through its wall, in each of which is disposed a stabilizer blade 49. Any suitable number of slots 48 and 49 may be provided, preferably three or more. Each stabilizer blade 49 is an elongate bar-like member having a smooth arcuate outer surface 50, as seen in FIG. 4, and having a shaped inner surface as seen in FIGS. 1C and 1D. The inner surfaces of the blades 49 have inwardly protruding formations 51a, 51b, 51c. Blade expander body 52 has correspondingly shaped recesses 53a, 53b, 53c, therearound. The protruding portions 51a-51c are received in the recesses 53a-53c, respectively. Protruding portions 51a and 51c are slotted at 54a, 54c to receive the leaf springs 55, 56, respectively. Stabilizer blades 49 each has flanges 58 along its opposite inner sides to prevent the stabilizer blades from moving out of the slots 48. A seal 59 surrounds the periphery of each stabilizer blade 49 to seal between the blade and the lower housing 45. The lower end of blade expander body 52 is thin walled and spaced uniformly inwardly from lower body member 45. A slidable balance piston 60 is disposed in the annular space between member 52 and lower body member 45 as shown in FIG. 1E. Piston 60 maintains a balance between the pressures in annular space 61 and the drill string bore space 62 therebelow. Inner and outer O-ring seals 63, 64 and wiper rings 65, 66 are provided in suitable interior and exterior grooves around piston 60. Piston 60 is stopped against further downward movement by an upwardly facing shoulder 67 formed at the lower interior of body member 45. At the lower end of body member 45, there is provided a threaded pin 68 for use in connecting the apparatus of the invention to a lower portion of the drill string. Referring to FIG. 1B, one or more oil injection ports 70 (one shown) each closeable by a screwed in plug 71 having a pair of O-ring seals therearound enables injection of lubricating oil around the cam body 35 and around blade actuator sleeve 52, for lubrication of the barrel cam 42 and the actuating body movements against the interior surfaces of the stabilizer blades. The annular space 61 is, therefore, filled with oil and the oil pressure is balanced by movement of piston 60 as before described. A camming pin 73 is screwed into a port 74 having internal threads, and an O-ring seal 75 provides a seal around the camming pin in port 74. The frustoconical tip 76 of the camming pin engages in barrel cam groove 42.
Accumulator end member 28 has a plurality of wrench slots 77 in its upper surface to enable it to be screwed into the threaded connection 30. Actuator body 52 has a plurality of wrench slots 78 in its lower end to enable body 52 to be screwed to cam body 35 at threaded connection 80. The bore 81 of piston sleeve 24 is usually two inches or greater in diameter so that a full flow passage through the apparatus is provided. The apparatus members below sleeve 24 have passages therethrough of at least the same size. Piston sleeve 24 is urged upwardly by the fluid pressure in accumulator space 32 and by compression spring 39 which acts upwardly on cam body 35 screwed to sleeve 24 at threaded connection 82. When the internal drill string fluid pressure is increased to a magnitude sufficiently high, piston sleeve 24 and cam body 35 connected therebelow, and actuating sleeve 52 are all moved downwardly because of the larger upper surface area of piston sleeve 24. The outwardly thicker areas 84-86 of the actuating sleeve 52 are forced at their end inclines onto the inwardly protruding areas 51a-51c of the stabilizer blades 49. The stabilizer blades are forced outwardly in slots 48 to the larger diameters shown in FIG. 4 and indicated by dashed lines 49a in FIG. 1D. The expanded blades perform their stabilizing and centralizing functions after piston sleeve 24 has been pushed downwardly, pushing cam body 35 and body 52 downwardly. Pin 73 moves in barrel cam groove 42 according to the barrel cam pattern.
The pin 73 remains stationary, and the cam body 35 is forced to rotate thereby. Referring to FIG. 3 of the drawings, if pin 73 is initially at point A of the barrel cam groove, downward movement of cam body 35 causes the pin to move in the groove to point B. Release of pressure within the drill string enables accumulator pressure and spring 39 to move the cam body 35 and sleeve 24 upwardly so that pin 73 moves to point C of the cam groove. Repeated increase of the internal drill string pressure moves pin 73 to point D of the cam groove. Another release of drill string pressure moves the pin to point E and successive increases and reductions of drill string pressure move pin 73 serially to points D through A of the barrel cam groove. When pin 73 is at points B, D, F, H, J, L, of the barrel cam groove, the stabilizer blades are expanded. When the camming pin is at points C, G, and K of the barrel cam groove, the stabilizer blades are maintained expanded while the drill string pressure is decreased and sleeve 24 is moved partway upwardly. When pin 73 is at points A, E, I or A of the barrel cam groove, the stabilizer blades are retracted by springs 55 and 56. While the shape of the barrel cam groove shown in FIG. 3 is satisfactory and may be preferred, other forms of barrel cam grooves may be used when determined to be suitable. It should be understood that the changes in drill string internal pressure may be satisfactorily controlled by operation of a surface pump, and pressuring and depressuring of the drill string interior may be done very rapidly, so that pin 73 may be moved through the full circuit of the barrel cam groove in a short period of time.
Referring now to FIGS. 1F, 1G, 1H and 1J of the drawings, there is shown therein a modified form of the lower portion of the apparatus, from the lower end of upper body member 10 to the lower end of the apparatus. Upper body member 10a has internal threads 91 into which a stationary seal ring 92 is screwed. Ring 92 has internal seals 93, 94 to seal it with cam element 35a. Washers 95, 96 are disposed upon the upper end of ring 92, and the lower end of spring 39 bears thereagainst.
Body member 45a is connected to upper body member 10a at threaded connection 46. Body member 45a is elongated between slots 48 and connection 46, and a movable seal ring 97 is slidably disposed between cam member 35a and the interior of body member 45a, as shown. A fluid port 98 is provided through body member 45a above seal ring 97. Upward movement of seal ring 97 is limited by engagement thereof with stationary seal ring 92, while both upward and downward movements thereof are caused and controlled by the volume displacement of the blades 49a moving inward and outward as has been described for the first disclosed form of the apparatus shown in FIGS. 1A-1E and 2-4. The blades 49a, usually three in number disposed in slots 48 circularly equally spaced around body member 45a, are moved outward by downward movement of cam body 52 and are moved inward by springs 55a, 56a after cam member 52 has been moved upward, as has already been described. Springs 55a, 56a are disposed in vertical slots 54d, 54e in the inner sides of the blades 49a.
Seal ring 60a is disposed against a downwardly facing shoulder 100 around the lower interior of body member 45a and seals with sleeve 101 connected to the lower end of cam member 52 at threaded connection 102. Seal 60a is not slidably movable as was seal 60 of the other embodiment, and is stationary.
As will by now be evident, the liquid volume displacements within the apparatus caused by inward and outward movements of the blades 49a are accompanied by respective upward and downward movements of slidably movable seal 97, seal 97 functioning as a piston. Fluid pressure within the apparatus is equalized with fluid pressure outside of the apparatus at piston 97, fluid entering or leaving the apparatus above piston 97 through flow port 98. Unless leaks occur at one or more of the seals 59, 103, 104-107, 108-111, a fixed volume of fluid is retained below piston 97 and above ring 60a, and between cam member 52, and sleeve 101 and body member 45a and blades 49a.
The apparatus, otherwise, operates in exactly the same manner as the first embodiment.
The ports through body member 45a which are closed by removable screwed in plugs 114, 115 are provided to enable introduction of a lubricant, such as oil, into the annular space behind blades 49a, so that the mutual sliding motions between blades 49a and cam member 52 will be of low friction.
It will further be understood that expansions and retractions of the stabilizer blades may be used in connection with directional drillng, in a manner known in the art. However, pulling and rerunning of the drill string to relocate positions of expanded stabilizer blades will not be necessary when the apparatus herein disclosed is used.
While a preferred embodiment of apparatus according to the invention has been described and shown in the drawings, many modifications thereof may be made by a person skilled in the art without departing from the spirit of the invention, and it is intended to protect by Letters Patent all forms of the invention falling within the scope of the following claims.
|
Surface controlled blade stabilizer apparatus, for which surface control is achieved by alteration of internal drill string pressure to move a piston which carries an actuator for expanding the stabilizer blades, the blades being spring biased inwardly when not forced outwardly by the actuator. A barrel cam controls and guides the actuator to downward, upward and intermediate positions, so that the blades may be expanded, retracted, or held expanded when drill string pressure is reduced. The apparatus has a full open passage therethrough which is not interfered with by operation of the apparatus.
| 4
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to radiator grills for automotive vehicles. More specifically, the invention relates to a side attachment arrangement for connecting a radiator grill to a bumper facia.
2. Description of the Related Art
The Insurance Institute for Highway Safety (IIHS) presently conducts among other tests a low-speed bumper test on new vehicle models in order to assess performance and repair costs associated with damage resulting from the test. In this test, the vehicle is crashed four separate times at 5 mph—both front and rear bumpers into a flat barrier, the front bumper into an angle barrier and the rear bumper into a short pole. Ratings are then given on the usual “Good” to “Poor” scale based on repair costs.
Most vehicles today, especially passenger cars, utilize wrap-around style front bumpers and center radiator grills that are made of resin. Typically, the bumper and grill are each fixedly secured to the vehicle body or chassis using bolts, screws, push fasteners and the like. Resins have become the materials of choice for such applications, due to the relative light weight and design flexibility over comparable metal equivalents. Plastic bumpers and grills are, however, particularly susceptible to damage during frontal impacts, including low speed impact events similar to those encountered in the IIHS testing. During a low speed frontal impact event, such as the IIHS flat barrier test, it has been repeatedly observed in a variety of vehicles that the front bumper and grill are displaced relative to the vehicle chassis and damaged as a result. Often the bumper and/or grill are damaged to such an extent that they must be replaced. Replacement costs for these parts are relatively high and are often the root cause of “poor” IIHS performance ratings.
Thus, it remains desirable to provide a plastic bumper and grill design that is less susceptible to damage during low-speed frontal impacts, such as those encountered in IIHS testing.
SUMMARY OF THE INVENTION
According to one aspect of the invention, a side attachment is provided for attaching a grill to a front bumper of a vehicle that allows the grill to pivot independently relative to the front bumper during a frontal impact of the vehicle, thereby minimizing damage to the grill and associated repair costs. More specifically, the front bumper extends along a front end of the vehicle. The grill is pivotally coupled to the front bumper for rotation about a substantially horizontal pivot axis relative to the front bumper. The grill has a bottom end releasably coupled to the front bumper allowing rotation of the grill relative to the front bumper about the pivot axis when the front bumper is deformed during a front impact event.
BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of the present invention will be readily appreciated 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 an exploded front perspective view of a grill and bumper assembly according to one embodiment of the invention; and
FIG. 2 is an enlarged rear perspective view of the grill and bumper assembly.
DETAILED DESCRIPTION OF THE INVENTION
The invention relates to an attachment of a front radiator grill to a front bumper of an automotive vehicle. The attachment allows the front grill to rotate relative to the front bumper during an impact between an object and the front bumper, so as to minimize damage to the front grill and costs associated with the repair of the vehicle due to the impact.
Referring to FIGS. 1 and 2 , a vehicle bumper 10 is adapted to be fixedly secured to a front end of an automotive vehicle. The bumper 10 includes a generally horizontal beam section 12 that extends transversely along the front end of the vehicle. The beam section 12 includes opposite top 14 and bottom 16 edges. A pair of pillars 20 , 22 extends upwardly from the top edge 14 of the bumper 10 . The pillars 20 , 22 are spaced apart from the ends of the beam section 12 to define spaces for receiving headlamp housings. The pillars 20 , 22 are also spaced apart to receive a front grill 50 therebetween.
Each pillar 20 , 22 includes a front face extending between spaced apart inner 32 and outer side walls. Each inner wall 32 includes a rear edge 34 . A slot 36 extends from the rear edge 34 of the inner wall 32 . The slot 36 is positioned adjacent the upper end of the pillar 20 , 22 . A conventional spring-clip nut 40 is secured to the inner wall 32 . The nut 40 includes a threaded bore 42 aligned with the slot 36 .
The grill 50 is generally rectangular shaped as viewed from the front of the vehicle. The grill 50 includes opposite top 52 and bottom 54 ends extending between opposite and spaced apart sides 56 , 58 . A hole 60 is formed in each side of the grill 50 . The holes 60 in the grill 50 are substantially axially aligned with the slots 36 in the pillars 20 , 22 , when the grill 50 is seated in the space between the pillars 20 , 22 .
The grill 50 is assembled to the bumper 10 by first positioning the grill 50 between the pillars 20 , 22 . Flanges 28 extend outwardly from the pillars 20 , 22 to engage corresponding slots in the grill 50 to facilitate location of the grill 50 relative to the bumper 10 . Threaded fasteners 70 are inserted through the holes 60 in the grill 50 and the slots 36 along the rear edge 34 of the bumper 10 . The fasteners 70 are threadingly engaged with the nuts 40 and tightened to secure the grill 50 to the bumper 10 . Tabs 72 extend outwardly from the bottom end 54 to secure the grill 50 to along the top edge 14 of the beam section 12 . Optionally, push or barb-type fasteners are inserted through corresponding holes formed in the bumper 10 and grill 50 .
During the IIHS flat barrier front impact test, or other similar low-speed impact event, the front bumper 10 is compressed, deformed and displaced rearwardly and downwardly relative to the front end of the vehicle chassis. The grill 50 is displaced along with the bumper 10 , until the tabs 72 disengage from the top edge 14 of the beam section 12 . The grill 50 and bumper 10 , however, remain attached by the threaded fasteners 70 and are freely pivotable relative to each other about a pivot axis 80 defined through the holes 60 in the grill 50 . As has been shown in repeated testing, pivotal movement of the grill 50 relative to the bumper 10 during the impact event minimizes structural damage to the grill 50 . Thus, the grill 50 is generally re-usable, notwithstanding any minor cosmetic damage due to abrasions. Re-use of the grill 50 during a repair of the vehicle significantly reduces the repair costs.
The invention has been described in an illustrative manner. It is, therefore, to be understood that the terminology used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. For example, the bumper 10 and grill 50 are typically formed from a glass-reinforced plastic in an injection molding process, but can be produced from any suitable materials and by any suitable methods known by those having ordinary skill in the art. Further, any conventional fastener 70 can be used for coupling the grill 50 to the bumper 10 , as long as it allows pivotal movement of the grill 50 relative to the bumper 10 about the pivot axis 80 during a frontal impact event. Thus, within the scope of the appended claims, the invention may be practiced other than as specifically described herein.
|
A side attachment for attaching a grill to a front bumper of a vehicle allows the grill to pivot independently relative to the front bumper. The grill also includes tabs that locate the bottom edge of the grill to the front bumper and release the grill to allow rotation during a frontal impact of the vehicle, thereby minimizing damage to the grill.
| 1
|
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. patent application Ser. No. 13/996,386, filed Jul. 24, 2013, which granted as U.S. Pat. No. 9,206,401 on Dec. 8, 2015, which is a 371 of PCT/IB2010/056024, filed Dec. 22, 2010, the entire disclosure of each of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a therapeutic approach, either viral vector-mediated gene therapy or by administration of modified sulfatases, in particular the sulfamidase enzyme, to cross the blood-brain barrier and treat the CNS pathology in Mucopolysaccharidoses (MPS), in particular MPS type IIIA.
BACKGROUND OF THE INVENTION
[0003] Mucopolysaccharidosis type IIIA (MPS-IIIA) is an inherited disease caused by the deficiency of sulfamidase (SGSH), an enzyme involved in the stepwise degradation of large macromolecules called heparan sulfates. As a consequence, undegraded substrates accumulate in the cells and tissues of the affected patients causing cell damage. The central nervous system (CNS) is the predominant target of damage and in fact, MPS-IIIA patients show severe mental retardation and neuropathological decline that ultimately leads to death (often<20 years). Clinical symptoms include hyperactivity, aggressive behaviour and sleep disturbance (1).
[0004] A naturally occurring mouse model of MPS-IIIA has been identified with pathophysiology and symptoms that resemble the human condition (2-4). These mice represent an ideal model to study the physiopathology of this disorder and to test new therapeutic protocols.
[0005] The treatment of brain lesions represents the principal goal of any therapeutic approach for MPS-IIIA. A route to reach the brain consists in the direct injection of a therapeutic molecule directly into the brain. A number of different enzyme replacement therapy (ERT) protocols have been tested. In these protocols, a recombinant sulfamidase enzyme was administered through the direct injection into the brain of MPSIIIA mice. These strategies are able to delay the appearance of neurodegenerative changes when sulfamidase is administered in the younger mice (5, 6). In addition, a Gene Therapy protocol based on the intracerebral injection of the SGSH gene via AAV vectors was successfully developed by the authors of the invention (7). Although these direct brain-targeting approaches have been shown to be clinically effective they represent highly invasive approaches for human therapeutic applicability.
[0006] Since every neuron in the brain is perfused by its own blood vessel, an effective alternative low-invasive route to reach the brain is the intravenous administration of the therapeutic molecule (8). However, this very dense network of microvasculature, which forms the Blood-Brain Barrier (BBB), is not permeable to all the molecules and might impede effective delivery of therapeutic agents (9). Indeed, intravenous administration of lysosomal enzymes has produced a therapeutic effect on the somatic pathology of many LSDs but it has no or little effect on the CNS pathology due to the impermeability of the BBB to large molecules (10). In MPS-IIIA, it has been demonstrated that intravenous injection of sulfamidase does not alter the pathology or behavioural process occurring in the MPS-IIIA mouse brain when the enzyme is supplied after the BBB has been formed (11).
[0007] Importantly, a recent study by Urayama et al. demonstrated that sulfamidase is transported across the BBB in neonatal mice throughout the mannose 6-phosphate receptor-mediated transport but the influx into adult brain was negligible (12).
[0008] It is clear that in such context the real challenge for the therapy of MPS-IIIA and in general for all LSDs involving the CNS is to develop CNS systemic treatment strategies that can overcome the major obstacle represented by BBB. An effective strategy to cross the BBB is the targeting of proteins to the CNS via receptor-mediated transcytosis (13). Well-characterized BBB receptors include: low density lipoprotein receptor (LDLR), the transferrin receptor (TfR), and the insulin-like growth factor receptor (IGF-R). The LDLR family represents a group of cell surface receptors that binds apolipoprotein (Apo) complexes (lipid carriers) for the internalizing into the lysosomes (14-16). On the surface of the BBB, LDLR binding to Apo results in the transcytosis to the luminal side of the BBB, where the apolipoprotein is released to be uptaken by neurons and astrocytes. A recent study has demonstrated that fusing the LDLR-binding domain of Apo to a lysosome enzyme results in an efficient delivery of the chimeric enzyme to the CNS (17).
[0009] WO2004108071 refers to a chimeric CNS targeting polypeptide comprising a BBB-receptor binding domain, such as the Apolipoprotein B binding domain, for therapeutic use in lysosomal storage diseases.
[0010] WO2004064750 refers to nucleic acids encoding a chimeric lysosomal polypeptide (specifically the lysosomal acid glucosidase GAA implicated in the lysosomal storage disorder Glycogen storage disease type II) comprising a secretory signal sequence (i.e. Vi-antitrypsin and alpha-1-antitrypsin) and the related AAV vectors.
[0011] WO2005002515 refers to a compound comprising a megalin-binding moiety conjugated to an agent of interest for receptor mediated drug delivery, particularly by transcytosis, across the blood-brain barrier. Moreover the document refers to a method of treating a lysosomal storage disease based on the administration of a composition comprising a megalin-binding moiety. Apolipoprotein B and Mucopolysaccharidosis IIIA are mentioned.
[0012] WO2009131698 refers to a therapy based on a chimeric NaGlu enzyme characterized by an Apolipoprotein B binding domain and directed specifically to Mucopolysaccharidosis IIIB.
[0013] Cardone et al. (Hum Mol Gen, 2006 15(7):1225) describes the correction of Hunter syndrome (the lysosomal storage disease Mucopolysaccharidosis Type II) in the MPSII mouse model by liver-directed AAV2/8-TBG-mediated gene delivery.
[0014] WO2007092563 refers to a method and compositions for tolerizing a mammal's brain to exogenously administered acid sphingomyelinase polypeptide by first delivering an effective amount of a transgene encoding the polypeptide to the mammal's hepatic tissue and then administering an effective amount of the transgene to the mammal's central nervous system (CNS). The therapeutic approach is directed to Niemann-Pick disease, a lysosomal storage disease. Liver-specific promoters and AAV type 8 are mentioned.
[0015] WO2009075815 refers to methods of treating Pompe disease (a lysosomal storage disease) which involves the administration of an AAV vector in the context of enzyme replacement therapy. Liver-specific promoter (thyroid hormone-binding globulin promoter) and AAV type 8 are mentioned.
[0016] None of the above prior art cited documents disclose or even suggest the modified sulfamidase enzyme of the instant invention and that it may have a therapeutic effect for the treatment of MPS type IIIA.
SUMMARY OF THE INVENTION
[0017] As disclosed in the background art, brain pathology is the most common feature in lysosomal storage disorders. Therefore, the treatment of brain lesions represents the principal goal of any effective therapy for these disorders.
[0018] The major obstacle to efficiently treat the brain by systemic delivery of a therapeutic agent is the blood brain barrier (BBB).
[0019] Authors developed a new non-invasive therapeutic approach to treat the brain pathology in the mucopolysaccharidosis type IIIA (MPS-IIIA), a lysosomal storage disorder with a severe central nervous system involvement. This strategy is based on the construction of a chimeric sulfamidase (the sulfatase enzyme which is deficient in MPS-IIIA), optimized with two amino-acid sequences (one to the N-terminus and the other to the C-terminus of the protein) which confer to the modified sulfamidase the capability to be highly secreted and efficiently targeted to the brain by crossing the blood brain barrier (BBB). The modified enzyme is expressed by adeno-associated virus (AAV) serotype 8 which specifically target the liver and make it like a factory organ of the therapeutic enzyme.
[0020] The modified sulfamidase may be effectively used for both gene therapy and for enzyme replacement therapy (ERT).
[0021] The modification approach may be used for other lysosomal enzymes which are deficient in other mucopolisaccharidoses with severe CNS involvement.
[0022] Therefore it is an object of the instant invention a nucleotide sequence encoding for a chimeric sulfatase, said chimeric sulfatase essentially consisting in the N-terminal-C-terminal sequence order of: a) a signal peptide derived by either the human α-antitrypsin (hAAT) amino acid sequence or the human Iduronate-2-sulfatase (IDS) amino acid sequence; b) a human sulfatase derived amino acid sequence deprived of its signal peptide; c) the ApoB LDLR-binding domain.
[0023] In a preferred embodiment the encoded signal peptide has a sequence belonging to the following group: MPSSVSWGILLLAGLCCLVPVSLA (SEQ ID No. 2) or MPPPRTGRGLLWLGLVLSSVCVALG (SEQ ID No. 4 or 6).
[0024] In a preferred embodiment the nucleotide the human sulfatase is the human sulfamidase, more preferably the encoded human sulfamidase derived amino acid sequence has essentially the sequence:
[0000]
(SEQ ID No. 8)
MSCPVPACCALLLVLGLCRARPRNALLLLADDGGFESGAYNNSAIATPHL
DALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDVHHFNS
FDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSVLQVGR
NITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCEKFGNG
ESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGRMDQGV
GLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLLVSSPE
HPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTGRSLLP
ALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMPFPIDQ
DFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDPHETQN
LATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQCQPLHN
EL.
[0025] Such sequence is encoded by SEQ ID No. 7 nt sequence: 5′-ATGAGCTGCCCCGTGCCCGCCTGCTGCGCGCTGCTGCTAGTCCTGGGGCT CTGCCGGGCGCGTCCCCGGAACGCACTGCTGCTCCTCGCGGATGACGGAG GCTTTGAGAGTGGCGCGTACAACAACAGCGCCATCGCCACCCCGCACCTG GACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAATGCCTTCACCTCGGT CAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCACTGGCCTGCCCCAGC ATCAGAATGGGATGTACGGGCTGCACCAGGACGTGCACCACTTCAACTCC TTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAGCCAAGCTGGTGTGCG CACAGGCATCATCGGGAAGAAGCACGTGGGGCCGGAGACCGTGTACCCGT TTGACTTTGCGTACACGGAGGAGAATGGCTCCGTCCTCCAGGTGGGGCGG AACATCACTAGAATTAAGCTGCTCGTCCGGAAATTCCTGCAGACTCAGGA TGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACGACCCCCACCGCTGTG GGCACTCCCAGCCCCAGTACGGAACCTTCTGTGAGAAGTTTGGCAACGGA GAGAGCGGCATGGGTCGTATCCCAGACTGGACCCCCCAGGCCTACGACCC ACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACACCCCGGCAGCCCGAG CCGACCTGGCCGCTCAGTACACCACCGTCGGCCGCATGGACCAAGGAGTT GGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGTCCTGAACGACACACT GGTGATCTTCACGTCCGACAACGGGATCCCCTTCCCCAGCGGCAGGACCA ACCTGTACTGGCCGGGCACTGCTGAACCCTTACTGGTGTCATCCCCGGAG CACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTACGTGAGCCTCCTAGA CCTCACGCCCACCATCTTGGATTGGTTCTCGATCCCGTACCCCAGCTACG CCATCTTTGGCTCGAAGACCATCCACCTCACTGGCCGGTCCCTCCTGCCG GCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTTTGGCAGCCAGAGCCA CCACGAGGTCACCATGTCCTACCCCATGCGCTCCGTGCAGCACCGGCACT TCCGCCTCGTGCACAACCTCAACTTCAAGATGCCCTTTCCCATCGACCAG GACTTCTACGTCTCACCCACCTTCCAGGACCTCCTGAACCGCACCACAGC TGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTCATTACTACTACCGGG CGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCCCACGAGACCCAGAAC CTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGAGATGCTTCGGGACCA GCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCTGGGTGTGCGCCCCCG ACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGCCAGCCCCTCCACAAT GAGCTGTGA-3′.
[0026] In a preferred embodiment the encoded ApoB LDLR-binding domain has essentially the sequence: SVIDALQYKLEGTTRLTRKRGLKLATALSLSNKFVEGS (SEQ ID No. 10).
[0027] In a preferred embodiment the nucleotide sequence has essentially the sequence belonging to the following group:
[0028] SEQUENCES WITH FLAG (expert shall easily substitute the flag sequence with any other suitable spacer sequence):
[0000]
a) Assembly hAATsp-SGSH-3xflag cassette (1611).
(SEQ ID No. 11)
5′-
ATGCCGTCTTCTGTCTCGTGGGGCATCCTCGTGCTGGCAGGCCTGTGCTG
CCTGGTCCCTGTCTCCCTGGCTCGTCCCCGGAACGCACTGCTGCTCCTCG
CGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATCGCC
ACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAATGC
CTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCACTG
GCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTGCAC
CACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAGCCA
AGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGGAGA
CCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTCCTC
CAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATTCCT
GCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACGACC
CCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAGAAG
TTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCCCCA
GGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACACCC
CGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGCATG
GACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGTCCT
GAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCCCCA
GCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTGGTG
TCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTACGT
GAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCCCGT
ACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGCCGG
TCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTTTGG
CAGCCAGAGCCACCACGAGGTCACCATGTCCTACCCCATGCGCTCCGTGC
AGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCCTTT
CCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCTGAA
CCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTCATT
ACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCCCAC
GAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGAGAT
GCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCTGGG
TGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGCCAG
CCCCTCCACAATGAGCTGTCATCTAGAGGATCCCGGGCTGACTACAAAGA
CCATGACGGTGATTATAAAGATCATGACATCGACTACAAGGATGACGATG
ACAAGTAGTGA-3′
b) Assembly hIDSsp-SGSH-3xflag cassette
(16141 bp).
(SEQ ID No. 13)
5′-
ATGCCCCCGCCCCGCACCGGCCGCGGCCTGCTGTGGCTGGGCCTGGTGCT
GAGCAGCGTGTGCGTGGCCCTGGGCCGTCCCCGGAACGCACTGCTGCTCC
TCGCGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATC
GCCACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAA
TGCCTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCA
CTGGCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTG
CACCACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAG
CCAAGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGG
AGACCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTC
CTCCAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATT
CCTGCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACG
ACCCCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAG
AAGTTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCC
CCAGGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACA
CCCCGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGC
ATGGACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGT
CCTGAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCC
CCAGCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTG
GTGTCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTA
CGTGAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCC
CGTACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGC
CGGTCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTT
TGGCAGCCAGAGCCACCACGAGGTCACCATGTCCTACCCCATGCGCTCCG
TGCAGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCC
TTTCCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCT
GAACCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTC
ATTACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCC
CACGAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGA
GATGCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCT
GGGTGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGC
CAGCCCCTACACAATGAGCTCTCATCTAGAGGATCCCGGGCTGACTACAA
AGACCATGACGGTGATTATAAAGATCATGACATCGACTACAAGGATGACG
ATGACAAGTAGTGA-3′
c) Assembly hAATsp-SGSH-3xflag-ApoB cassette
(1734 bp).
(SEQ. ID No. 15)
5′-
ATGCCGTCTTCTGTCTCGTGGGGCATCCTCCTGCTGGCAGGCCTGTGCTG
CCTGGTCCCTGTCTCCCTGGCTCGTCCCCGGAACGCACTGCTGCTCCTCG
CGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATCGCC
ACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAATGC
CTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCACTG
GCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTGCAC
CACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAGCCA
AGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGGAGA
CCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTCCTC
CAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATTCCT
GCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACGACC
CCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAGAAG
TTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCCCCA
GGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACACCC
CGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGCATG
GACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGTCCT
GAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCCCCA
GCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTGGTG
TCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTACGT
GAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCCCGT
ACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGCCGG
TCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTTTGG
CAGCCAGAGCCACCACGAGGTCACCATGTCTTACCCCATGCGCTCCGTGC
AGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCCTTT
CCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCTGAA
CCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTCATT
ACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCCCAC
GAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGAGAT
GCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCTGGG
TGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGCCAG
CCCCTCCACAATGAGCTGTCATCTAGAGGATCCCGGGCTGACTACAAAGA
CCATGACGGTGATTATAAAGATCATGACATCGACTACAAGGATGACGATG
ACAAGATCTCTGTCATTGATGCACTGCAGTACAAATTAGAGGGCACCACA
AGATTGACAAGAAAAAGGGGATTGAAGTTAGCCACAGCTCTGTCTCTGAG
CAACAAATTTGTGGAGGGTAGTAGATCTTAGTGA-3′
d) Assembly hIDSsp-SGSH-3xflag-ApoB cassette
(1737 bp).
(SEQ ID No. 17)
5′-
ATGCCCCCGCCCCGCACCGGCCGCGGCCTGCTGTGGCTGGGCCTGGTGCT
GAGCAGCGTGTGCGTGGCCCTGGGCCGTCCCCGGAACGCACTGCTGCTCC
TCGCGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATC
GCCACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAA
TGCCTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCA
CTGGCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTG
CACCACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAG
CCAAGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGG
AGACCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTC
CTCCAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATT
CCTGCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACG
ACCCCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAG
AAGTTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCC
CCAGGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACA
CCCCGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGC
ATGGACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGT
CCTGAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCC
CCAGCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTG
GTGTCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTA
CGTGAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCC
CGTACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGC
CGGTCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTT
TGGCAGCCAGAGCCACCACGAGGTCACCATGTCCTACCCCATGCGCTCCG
TGCAGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCC
TTTCCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCT
GAACCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTC
ATTACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCC
CACGAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGA
GATGCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCT
GGGTGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGC
CAGCCCCTACACAATGAGCTCTCATCTAGAGGATCCCGGGCTGACTACAA
AGACCATGACGGTGATTATAAAGATCATGACATCGACTACAAGGATGACG
ATGACAAGATCTCTGTCATTGATGCACTGCAGTACAAATTAGAGGGCACC
ACAAGATTGACAAGAAAAAGGGGATTGAAGTTAGCCACAGCTCTGTCTCT
GAGCAACAAATTTGTGGAGGGTAGTAGATCTTAGTGA-3′
SEQUENCES WITHOUT FLAG:
[0029]
[0000]
e) Assembly hAATsp-SGSH cassette.
(SEQ ID No. 19)
5′-
ATGCCGTCTTCTGTCTCGTGGGGCATCCTCCTGCTGGCAGGCCTGTGCTG
CCTGGTCCCTGTCTCCCTGGCTCGTCCCCGGAACGCACTGCTGCTCCTCG
CGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATCGCC
ACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAATGC
CTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCACTG
GCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTGCAC
CACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAGCCA
AGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGGAGA
CCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTCCTC
CAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATTCCT
GCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACGACC
CCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAGAAG
TTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCCCCA
GGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACACCC
CGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGCATG
GACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGTCCT
GAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCCCCA
GCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTGGTG
TCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTACGT
GAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCCCGT
ACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGCCGG
TCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTTTGG
CAGCCAGAGCCACCACGAGGTCACCATGTCCTACCCCATGCGCTCCGTGC
AGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCCTTT
CCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCTGAA
CCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTCATT
ACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCCCAC
GAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGAGAT
GCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCTGGG
TGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGCCAG
CCCCTCCACAATGAGCTGTGA-3′
f) Assembly hIDSsp-SGSH cassette.
(SEQ ID No. 21)
5′-
ATGCCCCCGCCCCGCACCGGCCGCGGCCTGCTGTGGCTGGGCCTGGTGCT
GAGCAGCGTGTGCGTGGCCCTGGGCCGTCCCCGGAACGCACTGCTGCTCC
TCGCGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAAGAGCGCCATC
GCCACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAA
TGCCTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCA
CTGGCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTG
CACCACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAG
CCAAGCTGGTGTGCGCAGAGGCATCATCGGGAAGAAGCACGTGGGGCCGG
AGACCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTC
CTCCAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATT
CCTGCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACG
ACCCCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAG
AAGTTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCC
CCAGGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACA
CCCCGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGC
ATGGACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGT
CCTGAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCC
CCAGCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTG
GTGTCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTA
CGTGAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCC
CGTACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGC
CGGTCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTT
TGGCAGCCAGAGCCACCACGAGGTCACCATGTCCTACCCCATGCGCTCCG
TGCAGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCC
TTTCCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCT
GAACCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTC
ATTACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCC
CACGAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGA
GATGCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCT
GGGTGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGC
CAGCCCCTACACAATGAGCTCTGA-3′
g) Assembly hAATsp-SGSH-ApoB cassette.
(SEQ ID No. 23)
5′-
ATGCCGTCTTCTGTCTCGTGGGGCATCCTCCTGCTGGCAGGCCTGTGCTG
CCTGGTCCCTGTCTCCCTGGCTCGTCCCCGGAACGCACTGCTGCTCCTCG
CGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATCGCC
ACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAATGC
CTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCACTG
GCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTGCAC
CACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAGCCA
AGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGGAGA
CCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTCCTC
CAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATTCCT
GCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACGACC
CCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAGAAG
TTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCCCCA
GGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACACCC
CGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGCATG
GACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGTCCT
GAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCCCCA
GCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTGGTG
TCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTACGT
GAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCCCGT
ACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGCCGG
TCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTTTGG
CAGCCAGAGCCACCACGAGGTCACCATGTCTTACCCCATGCGCTCCGTGC
AGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCCTTT
CCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCTGAA
CCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTCATT
ACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCCCAC
GAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGAGAT
GCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCTGGG
TGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGCCAG
CCCCTCCACAATGAGCTGTCATCTAGATCTGTCATTGATGCACTGCAGTA
CAAATTAGAGGGCACCACAAGATTGACAAGAAAAAGGGGATTGAAGTTAG
CCACAGCTCTGTCTCTGAGCAACAAATTTGTGGAGGGTAGTAGATCTTAG
TGA-3′
h) Assembly hIDSsp-SGSH-ApoB cassette.
(SEQ ID No. 25)
5′-
ATGCCCCCGCCCCGCACCGGCCGCGGCCTGCTGTGGCTGGGCCTGGTGCT
GAGCAGCGTGTGCGTGGCCCTGGGCCGTCCCCGGAACGCACTGCTGCTCC
TCGCGGATGACGGAGGCTTTGAGAGTGGCGCGTACAACAACAGCGCCATC
GCCACCCCGCACCTGGACGCCTTGGCCCGCCGCAGCCTCCTCTTTCGCAA
TGCCTTCACCTCGGTCAGCAGCTGCTCTCCCAGCCGCGCCAGCCTCCTCA
CTGGCCTGCCCCAGCATCAGAATGGGATGTACGGGCTGCACCAGGACGTG
CACCACTTCAACTCCTTCGACAAGGTGCGGAGCCTGCCGCTGCTGCTCAG
CCAAGCTGGTGTGCGCACAGGCATCATCGGGAAGAAGCACGTGGGGCCGG
AGACCGTGTACCCGTTTGACTTTGCGTACACGGAGGAGAATGGCTCCGTC
CTCCAGGTGGGGCGGAACATCACTAGAATTAAGCTGCTCGTCCGGAAATT
CCTGCAGACTCAGGATGACCGGCCTTTCTTCCTCTACGTCGCCTTCCACG
ACCCCCACCGCTGTGGGCACTCCCAACCCCAGTACGGAACCTTCTGTGAG
AAGTTTGGCAACGGAGAGAGCGGCATGGGTCGTATCCCAGACTGGACCCC
CCAGGCCTACGACCCACTGGACGTGCTGGTGCCTTACTTCGTCCCCAACA
CCCCGGCAGCCCGAGCCGACCTGGCCGCTCAGTACACCACCGTCGGCCGC
ATGGACCAAGGAGTTGGACTGGTGCTCCAGGAGCTGCGTGACGCCGGTGT
CCTGAACGACACACTGGTGATCTTCACGTCCGACAACGGGATCCCCTTCC
CCAGCGGCAGGACCAACCTGTACTGGCCGGGCACTGCTGAACCCTTACTG
GTGTCATCCCCGGAGCACCCAAAACGCTGGGGCCAAGTCAGCGAGGCCTA
CGTGAGCCTCCTAGACCTCACGCCCACCATCTTGGATTGGTTCTCGATCC
CGTACCCCAGCTACGCCATCTTTGGCTCGAAGACCATCCACCTCACTGGC
CGGTCCCTCCTGCCGGCGCTGGAGGCCGAGCCCCTCTGGGCCACCGTCTT
TGGCAGCCAGAGCCACCACGAGGTCACCATGTCTTACCCCATGCGCTCCG
TGCAGCACCGGCACTTCCGCCTCGTGCACAACCTCAACTTCAAGATGCCC
TTTCCCATCGACCAGGACTTCTACGTCTCACCCACCTTCCAGGACCTCCT
GAACCGCACCACAGCTGGTCAGCCCACGGGCTGGTACAAGGACCTCCGTC
ATTACTACTACCGGGCGCGCTGGGAGCTCTACGACCGGAGCCGGGACCCC
CACGAGACCCAGAACCTGGCCACCGACCCGCGCTTTGCTCAGCTTCTGGA
GATGCTTCGGGACCAGCTGGCCAAGTGGCAGTGGGAGACCCACGACCCCT
GGGTGTGCGCCCCCGACGGCGTCCTGGAGGAGAAGCTCTCTCCCCAGTGC
CAGCCCCTCCACAATGAGCTGTCATCTAGATCTGTCATTGATGCACTGCA
GTACAAATTAGAGGGCACCACAAGATTGACAAGAAAAAGGGGATTGAAGT
TAGCCACAGCTCTGTCTCTGAGCAACAAATTTGTGGAGGGTAGTAGATCT
TAGTGA-3′.
[0030] It is a further object of the invention a recombinant plasmid suitable for gene therapy of MPS comprising the nucleotide sequence as above disclosed under the control of a liver specific promoter, preferably the liver specific promoter is the human thyroid hormone-globulin (TBG) promoter, more preferably the human thyroid hormone-globulin (TBG) promoter has essentially the sequence: 5′-GCTAGCAGGTTAATTTTTAAAAAGCAGTCAAAAGTCCAAGTGGCCCTTGGCAGC ATTTACTCTCTCTGTTTGCTCTGGTTAATAATCTCAGGAGCACAAACATTCCAGAT CCAGGTTAATTTTTAAAAAGCAGTCAAAAGTCCAAGTGGCCCTTGGCAGCATTTA CTCTCTCTGTTTGCTCTGGTTAATAATCTCAGGAGCACAAACATTCCAGATCCGG CGCGCCAGGGCTGGAAGCTACCTTTGACATCATTTCCTCTGCGAATGCATGTATA ATTTCTACAGAACCTATTAGAAAGGATCACCCAGCCTCTGCTTTTGTACAACTTT CCCTTAAAAAACTGCCAATTCCACTGCTGTTTGGCCCAATAGTGAGAACTTTTC CTGCTGCCTCTTGGTGCTTTTGCCTATGGCCCCTATTCTGCCTGCTGAAGACACTC TTGCCAGCATGGACTTAAACCCCTCCAGCTCTGACAATCCTCTTTCTCTTTTGTTT TACATGAAGGGTCTGGCAGCCAAAGCAATCACTCAAAGTTCAAACCTTATCATTT TTTGCTTTGTTCCTCTTGGCCTTGGTTTTGTACATCAGCTTTGAAAATACCATCCC AGGGTTAATGCTGGGGTTAATTTATAACTAAGAGTGCTCTAGTTTTGCAATACAG GACATGCTATAAAAATGGAAAGATGTTGCTTTCTGAGAGACTGCAG-3′ (SEQ ID No. 27).
[0031] The expert in the field will realize that the recombinant plasmid of the invention has to be assembled in a viral vector for gene therapy of lysosomal disorders, and select the most suitable one. Such viral vectors may belong to the group of: lentiviral vectors, helper-dependent adenoviral vectors or AAV vectors. As example lentiviral vectors for gene therapy of lysosomal storage disorders is described in Naldini, L., Blomer, U., Gage, F. H., Trono, D., and Verma, I. M. (1996a). In vivo gene delivery and stable transduction of nondividing cells by a lentiviral vector. Science 272(5259), 263-7; Consiglio A, Quattrini A, Martino S, Bensadoun J C, Dolcetta D, Trojani A, Benaglia G, Marchesini S, Cestari V, Oliverio A, Bordignon C, Naldini. In vivo gene therapy of metachromatic leukodystrophy by lentiviral vectors: correction of neuropathology and protection against learning impairments in affected mice L. Nat Med. 2001 March; 7(3):310-6; Follenzi A, Naldini L. HIV-based vectors. Preparation and use. Methods Mol Med. 2002; 69:259-74. As a further example helper-dependent adenoviral vectors are described in Brunetti-Pierri N, Ng P. Progress towards liver and lung-directed gene therapy with helper-dependent adenoviral vectors. Curr Gene Ther. 2009 October; 9(5):329-40.
[0032] In a preferred embodiment the recombinant plasmid derives from the plasmid vector AAV2.1 and is suitable for AAV viral vectors, preferably AAV serotype 8.
[0033] Then it is a further object of the invention a viral vector for gene therapy of lysosomal disorders comprising any of the recombinant nucleic acid vectors as above disclosed.
[0034] Preferably the lysosomal disorder is MPS, more preferably MPS type IIIA.
[0035] It is a further object of the invention a pharmaceutical composition comprising the viral vector as above disclosed, preferably for systemic administration.
[0036] It is a further object of the invention a chimeric sulfatase essentially consisting in the N-terminal-C-terminal sequence order of: a) a signal peptide derived by either the human α-antitrypsin (hAAT) amino acid sequence or the human Iduronate-2-sulfatase (IDS) amino acid sequence; b) an human sulfatase derived amino acid sequence deprived of its signal peptide; c) the ApoB LDLR-binding domain.
[0037] In a preferred embodiment the chimeric sulfatase has a signal peptide having a sequence belonging to the following group: (SEQ ID No. 2) or (SEQ ID No. 4).
[0038] In a preferred embodiment the chimeric sulfatase has a human sulfamidase derived sequence, preferably (SEQ ID No. 8).
[0039] In a preferred embodiment the chimeric sulfatase comprises an encoded ApoB LDLR-binding domain having essentially the sequence of (SEQ ID No. 10).
[0040] In a preferred embodiment the chimeric sulfatase has essentially the sequence belonging to the following group:
[0041] SEQUENCES WITH FLAG (expert shall easily substitute the flag sequence with any other suitable spacer sequence):
[0000]
a) hAATsp-SGSH-3xflag aminoacid sequence
(* = stop).
(SEQ ID No. 12)
MPSSVSWGILLLAGLCCLVPVSLARPRNALLLLADDGGFESGAYNNSAIA
TPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDVH
HFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSVL
QVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCEK
FGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGRM
DQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLLV
SSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTGR
SLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMPF
PIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDPH
ETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQCQ
PLHNELSSRGSRADYKDHDGDYKDHDIDYKDDDDK**
b) hIDSsp-SGSH-3xflag aminoacid sequence
(* = stop)
(SEQ ID No. 14)
MPPPRTGRGLLWLGLVLSSVCVALGRPRNALLLLADDGGFESGAYNNSAI
ATPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDV
HHFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSV
LQVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCE
KFGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGR
MDQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLL
VSSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTG
RSLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMP
FPIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDP
HETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQC
QPLHNELSSRGSRADYKDHDGDYKDHDIDYKDDDDK**
c) hAATsp-SGSH-3xflag-ApoB aminoacid sequence
(* = stop)
(SEQ ID No. 16)
MPSSVSWGILLLAGLCCLVPVSLARPRNALLLLADDGGFESGAYNNSAIA
TPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDVH
HFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSVL
QVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCEK
FGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGRM
DQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLLV
SSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTGR
SLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMPF
PIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDPH
ETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQCQ
PLHNELSSRGSRADYKDHDGDYKDHDIDYKDDDDKISVIDALQYKLEGTT
RLTRKRGLKLATALSLSNKFVEGSRS**
d) hIDSsp-SGSH-3xflag-ApoB aminoacid sequence
(* = stop)
(SEQ ID No. 18)
MPPPRTGRGLLWLGLVLSSVCVALGRPRNALLLLADDGGFESGAYNNSAI
ATPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDV
HHFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSV
LQVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCE
KFGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGR
MDQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLL
VSSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTG
RSLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMP
FPIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDP
HETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQC
QPLHNELSSRGSRADYKDHDGDYKDHDIDYKDDDDKISVIDALQYKLEGT
TRLTRKRGLKLATALSLSNKFVEGSRS**,
[0042] SEQUENCES WITHOUT FLAG:
[0000]
e) hAATsp-SGSH aminoacid sequence (* = stop)
(SEQ ID No. 20)
MPSSVSWGILLLAGLCCLVPVSLARPRNALLLLADDGGFESGAYNNSAIA
TPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDVH
HFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSVL
QVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCEK
FGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGRM
DQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLLV
SSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTGR
SLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMPF
PIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDPH
ETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQCQ
PLHNEL*
f) hIDSsp-SGSH aminoacid sequence (* = stop)
(SEQ ID No. 22)
MPPPRTGRGLLWLGLVLSSVCVALGRPRNALLLLADDGGFESGAYNNSAI
ATPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDV
HHFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSV
LQVGRNITRIKLIVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCE
KFGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGR
MDQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLL
VSSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTG
RSLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMP
FPIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDP
HETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQC
QPLHNEL*
g) hAATsp-SGSH-ApoB aminoacid sequence
(* = stop)
(SEQ ID No. 24)
MPSSVSWGILLLAGLCCLVPVSLARPRNALLLLADDGGFESGAYNNSAIA
TPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDVH
HFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSVL
QVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCEK
FGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQVTTVGRM
DQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLLV
SSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTGR
SLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMPF
PIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDPH
ETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQCQ
PLHNESSRSVIDALQYKLEGTTRLTRGLKLATALSLSNKFVEGSRS**
h) hIDSsp-SGSH-ApoB aminoacid sequence
(* = stop)
(SEQ ID No. 26)
MPPPRTGRGLLWLGLVLSSVCVALGRPRNALLLLADDGGFESGAYNNSAI
ATPHLDALARRSLLFRNAFTSVSSCSPSRASLLTGLPQHQNGMYGLHQDV
HHFNSFDKVRSLPLLLSQAGVRTGIIGKKHVGPETVYPFDFAYTEENGSV
LQVGRNITRIKLLVRKFLQTQDDRPFFLYVAFHDPHRCGHSQPQYGTFCE
KFGNGESGMGRIPDWTPQAYDPLDVLVPYFVPNTPAARADLAAQYTTVGR
MDQGVGLVLQELRDAGVLNDTLVIFTSDNGIPFPSGRTNLYWPGTAEPLL
VSSPEHPKRWGQVSEAYVSLLDLTPTILDWFSIPYPSYAIFGSKTIHLTG
RSLLPALEAEPLWATVFGSQSHHEVTMSYPMRSVQHRHFRLVHNLNFKMP
FPIDQDFYVSPTFQDLLNRTTAGQPTGWYKDLRHYYYRARWELYDRSRDP
HETQNLATDPRFAQLLEMLRDQLAKWQWETHDPWVCAPDGVLEEKLSPQC
QPLHNELSSRSVIDALQYKLEGTTRLTRKRGLKLATALSLSNKFVEGSR
S**
[0043] It is another object of the invention the chimeric sulfatase as above disclosed for medical use, preferably for the treatment of MPS, more preferably MPS type IIIA.
[0044] It is another object of the invention a pharmaceutical composition comprising the chimeric sulfatase as above disclosed and suitable diluents and/or recipients and/or carriers.
[0045] It is another object of the invention a method for treatment of a MPS pathology comprising the step of administering to a subject a suitable amount of the pharmaceutical composition comprising the viral vector for gene therapy as above disclosed. Preferably the MPS pathology is MPS type IIIA.
[0046] It is another object of the invention a method for treatment of a MPS pathology comprising the step of administering to a subject a suitable amount of the pharmaceutical composition comprising the chimeric sulfatase as above disclosed. Preferably the MPS pathology is MPS type IIIA.
[0047] Major advantage of the invention is that the chimeric molecule of the invention as produced and secreted by the liver is able to cross the BBB and thus potentially target to all brain districts.
[0048] Regarding the gene therapy approach, with respect to prior art Fraldi et al. HMG 2007 that describes AAV2/5 mediated gene therapy for MPS-IIIIA, the instant invention is less invasive because AAV8 vectors are administered systemically and not directly into the brain.
[0049] As to the enzyme replacement therapy approach with respect to the prior art Hemsley, K. M. and J. J. Hopwood, Behav Brain Res, 2005; Savas, P. S et al., Mol Genet Metab, 2004 and Hemsley, K. M., et al., Mol Genet Metab, 2007, the instant invention overcomes the necessity to repeat the injection of the enzyme and it is designed to cross the BBB. It is worth to point out that for ERT approaches the BBB and the high cost of the enzyme production are very important limitations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] FIG. 1 . Non-modified SGSH: Preliminary in vivo study 1 (newborn treatment). Analysis of GFP signal in liver of newborn MPSIIA mice injected with AAV2/8-TBG-GFP. Newborn MPSIIIA were injected with AAV2/8-TBG-SGSH vectors (expressing a not-modified sulfamidase). As control, newborn MPSIIIA and Heterozygous (phenotypically normal) mice were injected with AAV2/8-TBG-GFP vectors. Liver sections from MPS-IIIA injected mice were analyzed for GFP staining at different time after injection (1, 2, 3, 5 and 10 weeks after injection). The GFP signal was very strong at early time points. However, a significant decrease of GFP signal was observed at later time point after injection
[0051] FIG. 2A . Non-modified SGSH: Preliminary in vivo study 1 (newborn treatment). SGSH activity in the serum of newborn injected mice. The sulfamidase activity was measured in the serum of MPSIIIA mice injected with AAV2/8-TBG-SGSH and control mice (MPS-IIIA and heterozygous mice injected with AAV2/8-TBG-GFP). The SGSH activity in plasma of AAV2/8-TBG-SGSH-treated MPS-IIIA mice increased during the first two weeks period after neonatal treatment, and then decreased through the time to reach the levels measured in control GFP-injected MPS-IIIA mice.
[0052] FIG. 2B . Non-modified SGSH: Preliminary in vivo study 1 (newborn treatment). SGSH activity in the liver of newborn injected mice. The sulfamidase activity was measured in the liver of MPSIIIA mice injected with AAV2/8-TBG-SGSH and control mice (MPS-IIIA and heterozygous mice injected with AAV2/8-TBG-GFP. The analysis of liver SGSH activity showed a trend similar to that observed in the plasma with higher levels of activity detected within the first week after injection.
[0053] FIG. 3 . Non-modified SGSH: Preliminary in vivo study 2 (adult treatment). Analysis of GFP signal in liver of adult MPSIIA mice injected with AAV2/8-TBG-GFP. 1.5 months old MPSIIIA were injected with AAV2/8-TBG-SGSH vectors (expressing a not-modified sulfamidase). As control, 1.5 months old MPSIIIA and Heterozygous (phenotypically normal) mice were injected with AAV2/8-TBG-GFP vectors. Liver sections from MPS-IIIA injected mice were analyzed for GFP staining at 1 and 5 weeks after injection. A high and stable expression of the GFP was observed.
[0054] FIG. 4A . Non-modified SGSH: Preliminary in vivo study 2 (adult treatment). SGSH activity in the liver of adult injected mice. The sulfamidase activity was measured in the liver of MPSIIIA mice injected with AAV2/8-TBG-SGSH and control mice (MPS-IIIA and heterozygous mice injected with AAV2/8-TBG-GFP). In the liver of MPSIIIA mice injected with AAV2/8-TBG-SGSH a strong increase in the SGSH activity was observed compared to the low enzyme activity detected in the animals injected with GFP vector. In addition, this activity remained stable for 5 weeks after injection (the last time point analyzed).
[0055] FIG. 4B . Non-modified SGSH: Preliminary in vivo study 2 (adult treatment). SGSH activity in the serum of adult injected mice.
[0056] Consistently, the analysis of SGSH activity in the serum of MPS-IIIA mice treated with AAV2/8-TBG-SGSH was very high and stable during throughout the analyzed post-injection time.
[0057] FIG. 5 . Chimeric sulfamidase constructs. The signal peptide (SP) of sulfamidase was replaced with that of either human α-antitrypsin (hAAT) or Iduronate-2-sulfatase (IDS). The constructs were designed as “partially engineered sulfamidase proteins” (IDSsp-SGSHflag and hAATsp-SGSHflag). To build the final chimeric sulfamidase proteins, the ApoB LDLR-binding domain (ApoB-BD) was fused at the C-terminus of the Flag tag to obtain the resulting “finally engineered constructs” (IDSsp-SGSHflag-ApoB and hAATsp-SGSHflag-ApoB). The ApoB sequence (114 bp) was amplified by PCR from the human blood cDNA using forward and reverse oligonucleotides with 5′ Bg1II sites. The backbone plasmid containing the SP-SGSH sequence was prepared inserting by mutagenesis the Bg1II site before the stop codon of Flag tag. All the resulting chimeric sulfamidase sequences (IDSsp-SGSHflag. hAATsp-SGSHflag. IDSsp-SGSHflag-ApoB and hAATsp-SGSHflag-ApoB) were inserted in mammalian expression plasmids under a CMV promoter.
[0058] FIG. 6 . Receptor-mediated transport. Crossing the BBB via receptor-mediated transcytosis. The Low Density Lipoprotein receptor (LDLR)-binding domain of the Apolipoprotein B (ApoB LDLR-BD) confers to the sulfamidase the capability to reach the brain cells by binding LDL receptors, which are abundant on the endothelial cells of BBB. This mechanism may substitute the mannose-6-phosphate receptor (M6PR)-mediated transport of the sulfamidase throughout the BBB, which is inefficient.
[0059] FIG. 7A . In vitro study. SGSH activity in the pellet and in the medium of transfected MPS-IIIA MEF cells. MEF cells derived from MPS-IIIA mice were transfected with either partially or finally engineered constructs. The activity of sulfamidase was measured in the medium (dark grey) and in the pellet (light grey) of transfected cells.
[0060] FIG. 7B . In vitro study. SGSH activity in the pellet and in the medium of transfected MPS-IIIA MEF cells. MEF cells derived from MPS-IIIA mice were transfected with either partially or finally engineered constructs. The corresponding efficiency of secretion (activity in medium/total activity) was also evaluated.
[0061] FIG. 8 . In vitro study. Western blot analysis of all engineered sulfamidase proteins. MEF cells derived from MPS-IIIA mice were transfected with either partial or final engineered constructs or with control SGSH not modified construct. (A) blot analysis with anti-flag antibodies showing the correct expression of all the chimeric proteins. As a control of transfection efficiency the cells were co-transfected with the same concentration of a plasmid containing flag-tagged Syntaxin7, an unrelated protein. (B) Pulse and chase experiments were performed in the transfected cells to evaluate the turnover rate of the chimeric proteins (C) Cos-7 cells were transfected with either partially or finally engineered constructs or with control SGSH non modified construct. Lysosomal localization were observed in all transfected cells by immunostaining with anti-SGSH antibodies.
[0062] FIG. 9 . In vivo study. Preliminary in vivo results in MPS IIIA mice injected with finally engineered sulfamidase. Authors obtained preliminary but extremely encouraging results in MPS-IIIA mice injected with one of the final sulfamidase constructs: hAATsp-SGSHflag-ApoB. Adult MPS-IIIA mice were systemically injected with AAV2/8-TBG-hAATsp-SGSHflag-ApoB. A group of MPS-IIIA were also injected with AAV2/8-TBG-SGSH (containing the non-modified sulfamidase) as control. The mice were sacrificed one month after injection. In the mice injected with the chimeric sulfamidase we observed higher liver sulfamidase activity and a very strong increase in the sulfamidase secretion with respect to control mice. Moreover, we detected a significant increase in SGSH activity into the brain of mice injected with the chimeric sulfamidase compared to SGSH activity measures in the brain of mice injected with not-modified sulfamidase.
[0063] FIG. 10 . Map of AAV2.1 plasmid. Map of pAAV2.1 plasmid used for AAV2.8 viral vectors production. The plasmid contains the GFP gene under the control of the liver specific promoter TBG. The GFP sequence was replaced with the cDNAs coding the chimeric sulfamidase cassettes by using NotI and HindIII restriction sites. The resulting plasmid was transfected along with pAd helper, pAAV rep-cap plasmid in 293 cells to produce AAV2.8 viral vectors (see Methods).
DETAILED DESCRIPTION OF THE INVENTION
Methods
Construction of Chimeric SGSH Cassettes, Recombinant Nucleic Acid Vectors and Viral Vectors
[0064] The alternative signal peptides were produced by ligation of two fragments: a sequence from human SGSH cDNA (fragment I) and the signal peptide sequence (fragment II). Fragment I was amplified from a hSGSH expressing plasmid and started at the 3′ terminus of hSGSH signal peptide sequence (corresponding to the nucleotide in position 61 on the SGSH sequence) and extended to a unique XbaI site and contained the entire SGSH cDNA (oligos used: SGSHFOR 5′-CGT CCC CGG AAC GCA CTG CTG CTC CT-3′ (SEQ ID No. 28) and SGSHREV 5′-GCG GCC TCT AGA TGA CAG CTC ATT GTG GAG GGG CTG-3′ (SEQ ID No. 29)). Fragment II was unique for each expression cassette. For hAATsp-SGSH-cFlag, fragment II was synthesized by annealing two specific oligonucleotide sequences (hAATspFOR 5′-GGC CGC ATG CCG TCT TCT GTC TCG TGG GGC ATC CTC CTG CTG GCA GGC CTG TGC TGC CTG GTC CCT GTC TCC CTG GCT 3′ (SEQ ID No. 30) and hAATspREV 5′-AGC CAG GGA GAC AGG GAC CAG GCA GCA CAG GCC TGC CAG CAG GAG GAT GCC CCACGA GAC AGA AGA CGG CAT GC-3′ (SEQ ID No. 31)) containing the human α1-antitrypsin signal peptide sequence [human a1-antitrypsin cDNA: 72 bp]. The fragment encoding for such signal peptide was:
[0000]
(SEQ ID No. 1)
5′-ATGCCGTCTTCTGTCTCGTGGGGCATCCTCCTGCTGGCAGGCCTGTG
CTGCCTGGTCCCTGTCTCCCTGGCT-3′.
[0065] For IDSsp-SGSH-cFlag expression cassette, fragment II was synthesized by annealing two specific oligonucleotide sequences (IDSspFOR 5′-GGC CGC ATG CCC CCG CCC CGC ACC GGC CGC GGC CTG CTG TGG CTG GGC CTG GTG CTG AGC AGC GTG TGC GTG GCC CTG GGC-3′ (SEQ ID No. 32) and IDSspREV 5′-GCC CAG GGC CAC GCA CAC GCT GCT CAG CAC CAG GCC CAG CCA CAG CAG GCC GCG GCC GGT GCG GGG CGG GGG CAT GC-3′ (SEQ ID No. 33) containing the human Iduronate sulfatase signal peptide sequence [ Homo sapiens iduronate 2-sulfatase (IDS) cDNA: 75 bp]. The fragment encoding for such signal peptide was: 5′-ATGCCGCCACCCCGGACCGGCCGAGGCCTTCTCTGGCTGGGTCTGGTTCT GAGCTCCGTCTGCGTCGCCCTCGGA-3′ (SEQ ID No. 3) or an optimized sequenze 5′-ATGCCCCCGCCCCGCACCGGCCGCGGCCTGCTGTGGCTGGGCCTGGTG CTGAGCAGCGTGTGCGTGGCCCTGGGC-3′ (SEQ ID No. 5). The two above sequences differ only for the codon usage and encode for the same signal peptide aa. sequence (SEQ ID No. 4 or 6). The oligonucleotide sequences of fragment 11 have 5′ NotI site and 3′ blunt end site. The forward and reverse oligonucleotide sequences were incubated for three minutes at 100° C. After chilling at RT we added the PNK to oligos for 30 minutes at 37° C. The fragment I (5′NotI-3′blunt) and fragment II (5′blunt-3′Xba) were ligated with p3xFlag-CMV14 vector plasmid (5′Not-3′Xba). DH5a competent cells was transformed with the resulting ligation mix.
[0066] To obtain the complete SGSH chimeric constructs, the amino acid sequence 3371-3409 of human ApoB (114 bp: 5′TCTGTCATTGATGCACTGCAGTACAAATTAGAGGG CACCACAAGATTGACAAGAAAAAGGGGATTGAAGTTAGCCACAGCTCTGTC TCTGAGCAACAAATTTGTGGAGGGTAGT-3′ (SEQ ID No. 9) was amplified by a human cDNA library (oligos: ApoBDFOR 5′-AGA TCT CTG TCA TTG ATG CAC TGC AGT-3′ (SEQ ID No. 34) and ApoBDREV 5′-AGA TCT ACT ACC CTC CAC AAA TTT GTT GC-3′(SEQ ID No. 35)) and cloned into the Bg1II sites at 5′ terminus of 3xFlag tag of either hAATsp-SGSH-cFlag or IDSsp-SGSH-cFlag.
[0067] The different expression cassettes containing either the partial chimeric constructs (hAATsp-SGSH-cFlag and hIDSsp-SGSH-cFlag) or the complete chimeric constructs (hAATsp-SGSH-cFlag-ApoB and hIDSsp-SGSH-cFlag-ApoB) were subcloned in the pAAV2.1-TBG-GFP between NotI (5′) and HindIII (3′) (the GFP sequence was replaced with the expression cassettes). The resulting plasmids ( FIG. 10 ) were used to produce recombinant AAV serotype 8 (AAV2/8) (19). The AAV vectors were produced using a transient transfection of three plasmids in 293 cells: pAd helper, pAAV rep-cap (packaging plasmid containing the AAV2 rep gene fused with cap genes of AAV serotype 8), pAAV Cis (this plasmid is pAAV2.1-TGB vector expressing the chimeric sulfamidase proteins). The recombinant AAV2/8 viral vectors were purified by two rounds of CsCl, as described previously (19). Vector titers, expressed as genome copies (GC/ml), were assessed by real-time PCR (GeneAmp 7000 Applied Biosystem). The AAV vectors were produced by the TIGEM AAV Vector Core Facility (http://www.tigem.it/core-facilities/adeno-associated-virus-aav-vector-core).
Trasfections and Secretions in Cells.
[0068] Hela and MPSIIIA MEF Cells were maintained in DMEM supplemented with 10% FBS and penicillin/streptomycin (normal culture medium). Sub-confluent cells were transfected using Lipofectamine™ 2000 (Invitrogen) according to manufacturer's protocols. One day after transfection the medium was replaced with DMEM 0.5% FBS. Two days after transfection we collected the conditioned medium and the pellet for the enzyme assays and western blot analysis.
WB Analysis
[0069] 3xflag Lysis buffer 1× (50 mM Tris-HCl pH8, 200 mM NaCl, 1% Triton X100, 1 mM EDTA, 50 mM HEPES) was added to the cell pellets. The lysates were obtained by incubating the cell pellets with lysis buffer for 1 hour in ice. Protein concentration was determined using the Bio-Rad (Bio-Rad, Hercules, Calif., USA) colorimetric assay. The conditioned medium was concentrated in the vivaspin 500 (Sartorius) by centrifugation of the medium at 13,000 rpm for 7 min. Flagged sulfamidase proteins were revealed by Western Blot analysis using a anti-FLAG M2 monoclonal peroxidase-conjugate antibodies (A8592 Sigma-Aldrich) diluted 1:1000 in 5% milk.
Immunofluorescence
[0070] Cells were washed three times in cold PBS and then fixed in 4% paraformaldehyde (PFA) for 15 min. Fixed cells were washed four times in cold PBS, permeabilized with blocking solution (0.1% Saponin and 10% FBS in PBS) for 30 min and immunolabelled with appropriate primary antibody: Rabbit anti h-sulfamidase (1:300, Sigma). After four washes in PBS we incubated the cells with secondary antibody Anti-Rabbit Alexa fluor-488 conjugated (1:1000). Cells were then washed four times in cold PBS and mounted in Vectashield mounting medium.
Pulse and Chase
[0071] To determine degradation rates of sulfamidase enzyme, MPSIIIA MEFs transfected with different chimeric constructs were radiolabeled with 30 μCi/10 6 cells [35S]methionine:cysteine mixture (EasyTag™ EXPRE35S35S Protein Labeling Mix, [3S]; PerkinElmer) for 30 minutes in methionine:cysteine-free medium (Sigma) supplemented with 1% fetal calf serum. After extensive washing, cells were maintained in the presence of 5% fetal calf serum and supplemented with methionine and cysteine. Cells were recovered at different time points and lysed using 3xflag Lysis buffer. Lysates were cleared by centrifugation and supernatants were immunoprecipitated by using agarose-conjugated antibody against flag (anti-flag M2 affinity Gel, A2220 Sigma-Aldrich). After extensive washing with lysis buffer, the immunoprecipitate was subjected to SDS-PAGE. Dried gels were exposed to a PhosphorImager screen and quantified with a PhosphorImager system.
Animals
[0072] Homozygous mutant (MPS-IIIA, −/−) and heterozygous (phenotypically normal+/−) C57BL/6 mice were utilized. Consequently, the term ‘normal mice’ is used to refer to the mouse phenotype. Experiments were conducted in accordance with the guidelines of the Animal Care and Use Committee of Cardarelli Hospital in Naples and authorized by the Italian Ministry of Health.
Systemic Injection and Tissues Collection
[0073] Newborn MPS-IIIA and normal mice at postnatal day 0-1 were cryo-anesthetized. The vectors were delivered in the systemic route via temporal vein (2×10 11 particles in 100 μl). The adult MPSIIIA mice (1 month) were injected via caudal vein (2×10 11 particles in 100 μl). The serum of animals were collected at different time points after injection for the enzyme assays. To evaluate liver and brain transduction the animals were sacrificed at different time points. Some of them were perfused/fixed with 4% (w/v) paraformaldehyde in PBS, the liver was then removed for GFP staining. The remaining mice were sacrificed and liver and brain removed to measure SGSH activity.
SGSH Activity Assay
[0074] SGSH activity was measured following protocols described in Fraldi et al., Hum Mol Gen 2007).
GFP Analysis
[0075] Liver tissues were subjected to a saccharose gradient (from 10 to 30%) and incubated O/N in 30% saccharose at 4° C. Finally, tissues were embedded in OCT embedding matrix (Kaltek) and snap-frozen in a bath of dry ice and ethanol. Tissue cryosections were cut at 10 j m of thickness, washed with PBS for 10 min, mounted in Vectashield mounting medium and processed for GFP analysis.
Results
[0076] The aim of the project was to develop a low-invasive systemic gene therapy strategy based on the intravenous injection of AAV serotype 8. This serotype displays high tropism to the liver (18-20) and can be used to delivery of an engineered gene encoding a chimeric modified sulfamidase optimized (i) to be highly secreted from the liver thus reaching high levels of circulating enzyme in the blood stream. Sulfamidase is poor secreted respect to other sulfatase enzymes such as the iduronate-2-sulfatase (IDS). Sulfamidase signal peptide was replaced with that of either IDS or human α-antitrypsin (AAT), a highly secreted enzyme; (ii) to efficiently cross the BBB. The chimeric sulfamidase was further engineered with a specific brain-targeting protein domain, the (LDLR)-binding domain of the apolipoprotein B (ApoB LDLR-BD).
In Vivo Results in MPS IIIA Mice
[0077] The efficacy of the new treatment is strictly dependent on the ability of the liver to be highly transduced by the transgene in order to efficiently secrete in the blood stream the sulfamidase that will then cross the BBB and transduce the brain by means of its brain-target sequence. Therefore, the serum levels of the therapeutic enzyme may represent critical factor in determining the efficacy of the therapy. No previous studies have been done to analyze liver transduction and the systemic levels of SGSH upon systemic gene delivery of exogenous SGSH in MPS-IIIA mice. Thus, we decided to investigate this issue in order to produce useful preliminary data for designing an effective therapeutic strategy.
[0078] The delivery of therapeutic enzyme to neonatal mice is a useful tool to prevent pathology in MPS-IIIA mice. We then decided to test whether the AAV2/8-mediated systemic injection in newborn MPSIIIA could be a feasible approach to develop our new therapeutic strategy. To this aim we injected MPS-IIIA newborn mice with AAV2/8 containing the sulfamidase coding sequence under the control of a liver specific promoter (Thyroid hormone-globulin, TBG) in order to specifically target the liver and make it like a factory organ of the therapeutic enzyme. Mice were injected via temporal vein with 1×10 11 particles of virus. Three experimental groups of mice were established: control mice (heterozygous mice; these mice display a normal phenotype) treated with AAV2/8-TBG-GFP, MPS-IIIA mice treated with AAV2/8-TBG-GFP and MPS-IIIA mice treated with AAV2/8-TBG-SGSH.
[0079] To test the efficiency of injection we analyzed the GFP fluorescence in the liver of GFP-injected mice (normal and MPS-IIIA mice). The GFP signal was present at either early or late time point after injection; however, a significant decrease of GFP signal was observed in the liver of mice analyzed at later time point after injection ( FIG. 1 ).
[0080] The MPS-IIIA mice injected with AAV2/8-TBG-SGSH were checked for SGSH activity in plasma and in the liver at different time points after injection (5, 8, 10, 14 days and at 3, 4, 5, and 10 weeks). The SGSH activity in plasma of AAV2/8-TBG-SGSH-treated MPS-IIIA mice increased during the first two weeks period after neonatal treatment, and then decreased through the time to reach the levels measured in control GFP-injected MPS-IIIA mice ( FIG. 2A ). The analysis of liver SGSH activity showed a trend similar to that observed in the plasma with higher levels of activity detected within the first week after injection ( FIG. 2B ). This preliminary study in newborn mice demonstrated that although the liver is efficiently transduced by AAV2/8-mediated neonatal delivery of sulfamidase, the enzyme is present at low levels (comparable to control GFP-injected MPS-IIIA mice) into both the liver and serum after 1 week post-injection making this approach unfeasible to treat the brain.
[0081] To evaluate whether the proliferation of hepatocytes during the period after the treatment is responsible for the liver dilution of vector after neonatal injection we performed a new study based on the systemic (caudal vein injection) AAV2/8-mediated delivery of SGSH in adult mice (1.5 month of age), in which the liver has completed its growth.
[0082] Also in this study we established three experimental groups of mice: normal mice treated with AAV2/8-TBG-GFP, MPS-IIIA mice treated with AAV2/8-TBG-GFP and MPS-IIIA mice treated with AAV2/8-TBG-SGSH. The analysis of GFP expression, at different time points after treatment (1 week and 5 weeks after injection) underlined a high and stable expression of the transgene in the liver of adult treated mice ( FIG. 3 ).
[0083] MPSIIIA treated mice were also checked for the SGSH activity in the liver and in the serum at different time points (1 week, 2-, 3-, 4-, 5-weeks) after the treatment. In the liver of MPSIIIA mice injected with AAV2/8-TBG-SGSH we observed a strong increase of SGSH activity compared with low enzyme activity in the animals injected with GFP vector, and this activity remained stable until 5 weeks after injection (the later time point analyzed) ( FIG. 4A ). Also the analysis of SGSH activity in the serum of treated mice was very high and stable until during the entire post-injection period analyzed ( FIG. 4B ). Importantly, this treatment did not result in any detectable sulfamidase activity into the brain of AAV2/8-injected MPS-IIIA mice (not shown).
[0084] In conclusion these preliminary studies show that: (i) liver is highly transduced by AAV2/8-mediated systemic injection (ii) the decrease of SGSH activity in the newborn treated mice was due to the dilution of vector in the liver and allow us to consider the adult mice a good model to test the systemic treatment with AAV2/8 containing the chimeric sulfamidase (iii) the secreted (non modified) sulfamidase did not result in a detectable enzymatic activity into the brain. The latter is an expected result and further justifies the rationale behind the aim of our project.
Construction and Validation of the Chimeric Sulfamidase Proteins
[0085] In order to increase sulfamidase secretion from the liver and thus the amount of the enzyme in the blood stream available to specifically target the brain, we engineered the sulfamidase by replacing its own signal peptide (SP) with an alternative one. Two signal peptides have been tested, the Iduronate-2-sulfatase (IDS) signal peptide and the human α-antitrypsin (AAT) signal peptide ( FIG. 5 ). The rationale behind the use of these two signal peptides is that IDS is a lysosomal enzyme that was demonstrated to be secreted at high levels from the liver [21] while the AAT is a highly secreted enzyme. The final goal of our project is to produce a modified sulfamidase capable to cross the BBB and target the CNS via receptor-mediated transcytosis ( FIG. 6 ). For this reason before starting the experiments aimed at evaluating the therapeutic efficacy of the substituting SP signal in SGSH, we further engineered the modified SGSH with a specific brain-targeting protein domain, the Low Density Lipoprotein receptor (LDLR)-binding domain of the Apolipoprotein B (ApoB LDLR-BD). The Binding Domain of ApoB will allow the sulfamidase to reach the brain cells by binding LDL receptors, which are abundant on the endothelial cells of BBB ( FIG. 6 ). The two finally engineered sulfamidase constructs contain at C-terminal the ApoB LDLR-BD and at N-terminal either an IDS or an hAAT signal peptide (IDSsp-SGSHflag-ApoB and hAATsp-SGSHflag-ApoB) ( FIG. 5 ).
[0086] To evaluate the functionality of chimeric sulfamidase proteins we transfected MPSIIIA MEF cells with either partial or final engineered sulfamidase proteins and compared the outcomes with those resulting from the transfections with not-engineered sulfamidase. Surprisingly, we observed that SGSH activity in the pellet and in the conditioned medium was higher in the cells transfected with the final chimeric constructs compared with the activity measured in the cells transfected with the other constructs, indicating that finally engineered sulfamidase were efficiently secreted ( FIG. 7A ). Indeed, these results were associated with a higher secretion efficiency of the finally engineered sulfamidase enzymes with respect to non-engineered sulfamidase ( FIG. 7B ). However, this secretion efficiency was similar to that measured after transfection of partially chimeric sulfamidase (containing only the alternative signal peptide) ( FIG. 7B ). Remarkably, we observed that the modifications of the sulfamidase, in particular those present in the finally engineered sulfamidase, confer to the chimeric proteins a higher stability compared to the non-engineered sulfamidase ( FIGS. 8A and B). Thus, we concluded that the increase in the sulfamidase protein levels in the medium of cells transfected with engineered sulfamidase proteins was due to both increased efficiency in secretion and increased stability of engineered sulfamidase.
[0087] Moreover, immunostaining with anti-SGSH antibodies showed a lysosomal-like localization for both partial and final engineered constructs ( FIG. 8C ).
[0088] In conclusion these results demonstrate that: (i) the chimeric sulfamidase enzymes containing the alternative signal peptide are functional and active; (ii) they are more stable with respect to non-modified sulfamidase; (iii) they are secreted with increased efficiency compared to non-engineered sulfamidase enzyme; (iv) the introduction of the ApoB LDLR-BD to produce the finally engineered sulfamidase did not affect either the functionality or the increased secretion efficiency observed in the cells transfected with the partially engineered sulfamidase. In addition, the finally engineered constructs appear to be more stable compared to partially engineered constructs.
[0000] In Vivo Results in MPS IIIA Mice Injected with Finally Engineered Sulfamidase
[0089] We produced AAV2/8 vectors containing one of the finally engineered sulfamidase (hAATsp-SGSHflag-ApoB) under the liver specific promoter TBG. We obtained very preliminary but extremely encouraging results in MPS-IIIA injected with this viral vector. Adult MPS-IIIA mice were systemically injected with AAV2/8-TBG-hAATsp-SGSHflag-ApoB. A group of MPS-IIIA were also injected with AAV2/8-TBG-SGSH (containing the not modified sulfamidase) as control. The mice were sacrificed one month after injection. In the mice injected with the chimeric sulfamidase we observed higher liver sulfamidase activity and a very strong increase in the sulfamidase secretion respect to control mice (FIG. 9 ). Moreover, we detected a significant increase in SGSH activity into the brain of mice injected with the chimeric sulfamidase ( FIG. 9 ).
Use of Other Vectors
[0090] We completed the production of the AAV2/8 vectors containing all the engineered sulfamidase proteins (partial and final). Specifically, besides the AAV2/8-TBG-hAATsp-SGSHflag-ApoB, we now produced AAV2/8-TBG-hIDSsp-SGSHflag-ApoB; AAV2/8-TBG-hAATsp-SGSHflag and AAV2/8-TBG-hIDSsp-SGSHflag.
[0091] These vectors may be used to perform a large in vivo study by the following procedure: MPS-IIIA mice (1 month of age) are injected (by a caudal vein route of administration) with AAV2/8 vectors containing the engineered constructs in order to test the clinical efficacy of the chimeric sulfamidase enzymes. Results are useful to evaluate (i) the efficiency of CNS transduction and (ii) the rescue of CNS pathology in the treated mice.
BIBLIOGRAPHY
[0000]
1. Muenzer, J. (2004) The mucopolysaccharidoses: a heterogeneous group of disorders with variable pediatric presentations. J Pediatr, 144, S27-34.
2. Bhaumik, M., Muller, V. J., Rozaklis, T., Johnson, L., Dobrenis, K., Bhattacharyya, R., Wurzelmann, S., Finamore, P., Hopwood, J. J., Walkley, S. U. et al. (1999) A mouse model for mucopolysaccharidosis type III A (Sanfilippo syndrome). Glycobiology, 9, 1389-96.
3. Bhattacharyya, R., Gliddon, B., Beccari, T., Hopwood, J. J. and Stanley, P. (2001) A novel missense mutation in lysosomal sulfamidase is the basis of MPS III A in a spontaneous mouse mutant. Glycobiology, 11, 99-103.
4. Hemsley, K. M. and Hopwood, J. J. (2005) Development of motor deficits in a murine model of mucopolysaccharidosis type IIIA (MPS-IIIA). Behav Brain Res, 158, 191-9.
5. Savas. P. S., Hemsley, K. M. and Hopwood. J. J. (2004) Intracerebral injection of sulfamidase delays neuropathology in murine MPS-IIIA. Mol Genet Metab, 82, 273-85.
6. Hemsley, K. M., King, B. and Hopwood, J. J. (2007) Injection of recombinant human sulfamidase into the CSF via the cerebellomedullary cistern in MPS IIIA mice. Mol Genet Metab, 90, 313-28.
7. Fraldi, A., Hemsley, K., Crawley, A., Lombardi, A., Lau, A., Sutherland, L., Auricchio, A., Ballabio, A. and Hopwood, J. J. (2007) Functional correction of CNS lesions in an MPS-IIIA mouse model by intracerebral AAV-mediated delivery of sulfamidase and SUMF1 genes. Hum Mol Genet, 16, 2693-702.
8. Pardridge, W. M. (2002) Drug and gene delivery to the brain: the vascular route. Neuron, 36, 555-8.
9. Pardridge, W. M. (2005) Molecular biology of the blood-brain barrier. Mol Biotechnol, 30, 57-70.
10. Brady, R. O. and Schiffmann, R. (2004) Enzyme-replacement therapy for metabolic storage disorders. Lancet Neurol, 3, 752-6.
11. Gliddon, B. L. and Hopwood, J. J. (2004) Enzyme-replacement therapy from birth delays the development of behavior and learning problems in mucopolysaccharidosis type IIIA mice. Pediatr Res, 56, 65-72.
12. Urayama, A., Grubb, J. H., Sly, W. S. and Banks, W. A. (2008) Mannose 6-phosphate receptor-mediated transport of sulfamidase across the blood-brain barrier in the newborn mouse. Mol Ther, 16, 1261-6.
13. Pardridge, W. M. (2002) Targeting neurotherapeutic agents through the blood-brain barrier. Arch Neurol, 59, 35-40.
14. Brown, M. S. and Goldstein, J. L. (1986) A receptor-mediated pathway for cholesterol homeostasis. Science, 232, 34-47.
15. Stefansson, S., Chappell, D. A., Argraves, K. M., Strickland, D. K. and Argraves, W. S. (1995) Glycoprotein 330/low density lipoprotein receptor-related protein-2 mediates endocytosis of low density lipoproteins via interaction with apolipoprotein B100 . J Biol Chem, 270, 19417-21.
16. Boren, J., Lee, I., Zhu, W., Arnold, K., Taylor, S. and Innerarity, T. L. (1998) Identification of the low density lipoprotein receptor-binding site in apolipoprotein B100 and the modulation of its binding activity by the carboxyl terminus in familial defective apo-B100 . J Clin Invest, 101, 1084-93.
17. Spencer, B. J. and Verma, I. M. (2007) Targeted delivery of proteins across the blood-brain barrier. Proc Natl Acad Sci USA, 104, 7594-9.
18. Cheng, S. H. and Smith, A. E. (2003) Gene therapy progress and prospects: gene therapy of lysosomal storage disorders. Gene Ther, 10, 1275-81.
19. Gao, G. P., Alvira, M. R., Wang, L., Calcedo, R., Johnston, J. and Wilson, J. M. (2002) Novel adeno-associated viruses from rhesus monkeys as vectors for human gene therapy. Proc Natl Acad Sci US A. 99, 11854-9.
20. Wang, L., Takabe. K., Bidlingmaier, S. M., Ill, C. R. and Verma, I. M. (1999) Sustained correction of bleeding disorder in hemophilia B mice by gene therapy. Proc Natl Acad Sci USA, 96, 3906-10.
21. Cardone, M., et al., Correction of Hunter syndrome in the MPSII mouse model by AAV 2/8- mediatedgene delivery . Hum Mol Genet, 2006. 15(7): p. 1225-36.
|
The invention provides for nucleotide sequences encoding for a chimeric sulfatase, viral vectors expressing such sequences for gene therapy and pharmaceutical uses of the chimeric expressed protein. The invention is particularly applied in the therapy of mucopolysaccharidosis, preferably type IIIA.
| 2
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a cushion for positioning and supporting the foot or heel of an individual, and more particularly, a device for supporting the Achilles tendon and elevating the heel of a person while they lay for long periods of time in a supine position.
2. Description of the Related Art
Many devices for positioning, supporting or elevating various parts of the body of a person are well known. Pillows and cushions, both inflatable and non-inflatable, are utilized both in homes and institutions, such as hospitals. Institutions have also used other means of support, such as mechanical elevating systems, to elevate a person's extremity, especially with a view of preventing ulcerations.
Prior art devices were somewhat effective although improvements were desirable. For example, pillows tend to be too bulky or not easily adjustable to meet the needs of the comfort level of the individual. Mechanical devices tend to be large in construction, not feasible for in-home use, and are typically expensive. Some prior art devices were difficult to position properly if the user adjusted his position. If the user adjusted his position, for example by turning on his side, the prior art devices did not have the capability to turn with the user. Rather, the leg of the user had to be lifted and then repositioned onto the device.
Another problem not addressed by prior art devices concerned the configuration of the human foot. Because the heel of a user extends outwardly from the centerline of a person's leg, prior art devices that supported a user's foot often allowed the person's heel to touch the surface of the bed. This touching might lead to the circulatory problems addressed by the present invention.
Accordingly, it is the primary object of the present invention to provide for a heel elevator, which elevates the heel and foot of the user comfortably over long periods of time so as to improve circulation and prevent ulcerations.
Another object of the present invention is to provide a heel elevator, which is comfortable to a user in a supine position.
Another object of the present invention is to provide a heel elevator, which is effective in preventing ulcerations and in promoting circulation to the user's extremities.
Another object of the present invention is to provide a heel elevator, which conforms to the indentation behind a person's foot, allowing the heel of the user to hang downwardly without contacting the surface of the bed.
Another object of the present invention is to provide a heel elevator, which supports the heel and foot of the user even when rotating, or turning while in a supine position.
Another object of the present invention is to provide a heel elevator, which is economical in comparison to mechanical devices for supporting the heel and foot of the user.
Still another object of the present invention is to provide a heel elevator, which is easy to operate, maneuver, clean, maintain and repair.
SUMMARY OF THE INVENTION
The present invention includes an article for supporting a portion of a user's body. The article, when assembled, includes a body having first and second side panels and a middle panel. Each of the panels has an upper surface and a lower surface. A radius of curvature of the upper surface of the middle panel is less than a radius of curvature of the first side panel. Likewise, the radius of curvature of the upper surface of the middle panel is less than a radius of curvature of the upper surface of the second side panel. In addition, the radius of curvature of the upper surface of the middle panel is less than a radius of curvature of the lower surface of the middle panel. The radius of curvature of the lower surfaces of the middle, and side panels are approximately infinite.
The article when assembled includes a body having first and second side panels and a middle panel. Each of the panels have an upper surface and a lower surface displaced from their corresponding upper surface. The upper surface of the middle panel is displaced from the lower surface of the middle panel by a maximum distance H1. The upper surface of the first side panel is also displaced from the lower surface of the first side panel by a maximum distance H2 where the distance H1 is greater than the distance H2. Likewise, the upper surface of the second side panel is displaced from the lower surface of the second side panel by a maximum distance H3, where the distance H1 is greater than the distance H3.
The article can be inflatable with air, gel or the like. The middle panel has a volume V1 and the first side panel has a volume of V2, where volume V1 is greater than volume V2. The second side panel has a volume of V3 where volume V1 is greater than volume V3.
The article, when assembled, includes a separator having a first end, a second end, and a width. The separator separates air contained within the middle and first side panels. The panels have a first end and a last end and are heat-sealed. The panels each have a width and a length wherein the separator has a first air gap defined by the front edge of the panel and the first end of the separator. The separator has a second air gap defined by a rear edge of the panel and the second end of the separator. The first air gap is between 0.25 inches (0.635 cm) and 1.50 inches (3.375 cm). The first side panel folds along the separator.
The first side panel is connected to the first end of the middle panel and the second side panel is connected to the second end of the middle panel.
The article further includes connecting means for connecting enclosing means. The enclosing means encloses the heel elevator air bag by connecting the first end of the side panels and the last end of the panels. The connecting means can be a hook-and-loop trip.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of the novel heel elevator;
FIG. 2 is a front view of the novel heel elevator shown in an inflated, or filled, and assembled condition, wherein the phantom circle represents the ankle of a user;
FIG. 3 is a front view of the novel heel elevator shown in an unassembled, uninflated or unfilled, condition.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, which are for purposes of illustrating a preferred embodiment of the invention only, and not for purposes of limiting the invention, FIG. 1 shows the heel elevator uninflated or unfilled, unassembled, and in a flat position. A preferred embodiment of the heel elevator 10 comprises an inflatable or fillable air bag 11 having an inflation valve 12. The valve 12 allows air to be introduced into the air bag 11. A pressurized air source, such as an associated mechanical pump or an associated hand-operated pump (not shown), provides for entry of ambient air into the interior of the air bag 11. The valve 12 also includes a means for preventing discharge of the air. Deflation is also accomplished through the valve 12. Another embodiment of the valve 12 allows air to be introduced from the user's mouth. Such a valve is well known in the field of inflation valves, for example, in inflatable devices to be used in water, such as a beach ball. Another embodiment also allows the air bag 11 to be filled with other mediums such as water, gel, etc.
The inventive heel elevator 10 has a body 100 which is divided up into three panels, a bottom panel 14, a first side panel 16, and a second side panel 18. The panels 14, 16, 18 are separated by separators 20 which, in the preferred embodiment, are heat seals. Also in the preferred embodiment, the separators 20 do not extend across the entire width of the air bag 11. Because the separators 20 do not extend across the entire air bag 11, the air is able to flow from the inflation valve 12 to the panels 14, 16, 18.
Another embodiment of the heel elevator 10 includes an air bag 11, which is separated into separate panels. In this embodiment the heat separators 20 would extend across the entire width of the air bag 11, completely separating the panels 14, 16, 18 from each other. In such case, each of the panels 14, 16, 18 could be inflated by separate inflation valves placed into each of the panels 14, 16, 18.
The width of air gaps 26 is defined by the front edge 22 of air bag 11 and by first end 28 at separator 20. The width of the air gaps 26 must be great enough to allow air to pass freely into panels 14, 16, 18 yet must also be small enough to allow the air bag 11 to fold along edges 32 of separator 20. Second air gap 34 is preferably the same width as first air gap 26 and is defined by second end 30 of separator 20 and rear edge 24 of air bag 11. Elimination or reduction of either air gap 26 or 34 is within the scope of this invention. However, for uniformity sake the preferred air gaps 26 and 34 are equal. In the preferred embodiment, the air gaps 26, 28 are between 0.25 inches and 1.50 inches. The preferred width (X1) of the separators is between 0.25 and 1.50 inches with a preferred width being 0.25 inches.
In the preferred embodiment, the body 100, which is made up of panels 14, 16, 18 and separators 20, is essentially made of vinyl. The separators 20 are preferably manufactured through a heat sealing technique. The design and method of manufacturing the separators 20 enables them to provide flexible joints between flat bottom panel 14 and side panel 16, and middle panel 14 and side panel 18.
FIG. 1 shows air bag 11 having enclosing means 36 secured to, or incorporated within, side panel 16. Enclosing means 36 serves to attach the heel elevator 10 to the leg, foot or ankle of a user. The method of attachment encloses the leg of the user. Enclosing means 36 connects or attaches to side panel 18. FIG. 1 shows enclosing means 36 being hook-and-loop straps 37 which mesh with hook-and-loop elevators 38 that are attached to side panel 18. The hook-and-loop straps 37 and the hook-and-loop elevators 38 are attached to side panels 16, 18 by tape or other securing means. Enclosing means 37 encloses the first panel end 42 and the last panel end 44.
Referring to FIG. 3, the air supply (not shown) is introduced into valve 12. Air is introduced into the air bag 11 by the user or other means as have been described, thereby allowing air to flow through the valve 12 into the air bag 11. When the air bag 11 has achieved the desired inflation, the air supply is stopped and the inflation valve 12 is closed.
When the user desires less air in the air bag 11, inflation valve 12 is opened. Opening the inflation valve 12 permits the air to escape from the air bag 11 through the valve 12 to the atmosphere. When the desired deflation has been accomplished, the user closes the inflation valve 12, thereby stopping the flow of air from the air bag 11. The air pump, which is not shown, can be mechanical, electrical, or pneumatic.
Referring again to FIG. 3, an important feature of the invention will be described. When viewed in the unassembled, inflated position, as shown in FIG. 3, each panel 14, 16, 18 has an upper surface 104, 106, 108 and a lower surface 114, 116, 118. As is clearly evident from FIG. 3, the length of the upper surface 108, 104, 106 of each of the panels 18, 14, 16 is greater than the length of the lower surface 118, 114, 116 of each of the panels 18, 14, 16. The extra length of the upper surfaces causes the side cross sectional view of each of the panels 18, 14, 16 to be asymmetrical. The radius of curvature of the upper surfaces 108, 104, 106 is smaller than the radius of curvature of the lower surfaces 118, 114, 116 of the panels 18, 14, 16. In fact, in the preferred embodiment, the lower surfaces 118, 114, 116 are planar, yielding an infinite radius of curvature.
In the preferred embodiment, the radius of curvature of the upper surfaces 108, 106, 104 of the side panels 18, 16, are equal while the radius of curvature of the upper surface 104 of the middle panel 14 is smaller. The smaller radius of curvature of the upper surface of the middle panel is important because the foot of the user is to be elevated. Another important aspect of the smaller radius of curvature is that when side panels 18, 16 are assembled a user's ankle is enclosed securely therein.
Referring now to FIG. 2, the inflatable air bag 11 is shown in an inflated and assembled condition. The phantom circle 40, shown in the center of the air bag 11, depicts the leg of the user. The user is commonly in a supine position lying on a bed and the air bag 11 essentially encloses the users body part, preferably the ankle. In use, the user rests his ankle or, essentially, his Achilles tendon on middle panel 14. The user then secures the heel elevator 10 by using the enclosing means 36, such as a hook-and-loop strap 37, and secures the strap 36 to the hook-and-loop elevator 38. In this embodiment, the user's ankle 40 is enclosed within the air bag 11. The height "H1" of the middle panel 14 primarily depends upon the amount of air introduced into the inflatable air bag 11 which yields volume "V1". However, the volume V1 of air should be enough to allow the heel to be elevated from the surface, which the middle panel 14 rests upon. The heel should be elevated above and not touch the surface for maximum benefit from the invention. The height H1 of the middle panel 14 is preferably greater than the heights "H2" and "H3" of the side panels 16, 18. Similarly, volumes V2, V3 corresponding to panels 16, 18 are preferably less than volume V1 of middle panel 14. Heights H2 and H3 and volumes V2, V3 of side panels 16, 18 are preferably equal in height and volume although they could have unequal heights, volumes and still be within the scope of this invention. Height H1 and volume V1 may also be equal to or less than either heights H2 or H3 and volumes V2 or V3 if the user prefers to have support directed to another area, such as the side of the ankle.
The heel elevator 10, when inflated and assembled, is in essentially a triangular configuration which allows the user, while laying in a supine position, to rotate their bodies while still maintaining proper fit with the inventive heel elevator 10 and while still elevating the injured extremity above the surface of the bed. Therefore, if the user decides to roll over thereby placing his foot in a horizontal position, the air bag 11 still maintains contact with the user's foot and maintain its elevation above the bed surface.
Obviously, modifications and alterations will occur to others upon their reading and understanding of the specification. It is intended by applicant to include all such modifications and alterations insofar as they come within the scope of the appending claims or the equivalents thereof.
|
A heel support for supporting an person's extremity includes an inflatable air bag having three panels, a middle panel and two side panels. An upper surface of the middle panel has a smaller radius of curvature than upper surfaces of the side panels. The panels are connected together in a manner which allows the two side panels to collapse inwardly toward the bottom panel. The side panels fold inwardly toward one another and are secured by an attachment means, preferably hook-and-loop strips.
| 0
|
BACKGROUND OF INVENTION
Miniature inductors and transformers have recently been developed using very thin wall plastic tubes, in the order of 0.001 to 0.010 inches in thickness. Such tubes are made of extremely slippery plastic material having a low coefficient of friction. Such materials include, for example, various polyesters, polyamides, polyethylene terephthalate, fluorinated hydrocarbons and others plastics sold under such trademarks, for example, as Mylar, Teflon, Aramid and Kapton. Such plastics are used because their physical and electrical characteristics are ideal for use as thin walled dielectric tubes. Thin wall tubes permit the tuning element to be positioned close to the coil winding for improved inductance characteristics. Many of these plastics have such low coefficients of friction that it has been impossible to provide satisfactory means for securing a tuning element in the tube at variable selected locations. Normally the tuning element is a threaded element which screws into and out of the tube for tuning purposes. Unfortunately, no satisfactory means have been developed to provide internal threads on the inner surface of tubes formed of such plastics for the purpose of adjustably securing the tuning element within it. Some attempts have been made to crimp, dimple or form the thin wall tube with appropriate surface projections on the inner surface. This is difficult because these plastics have extreme memory properties or high coefficients of elasticity. Consequently it has not been possible to permanently form satisfactory dimples, crimps or other shapes on the inner surface of these thin wall tubes. Attempts have also been made to provide suitable threading surfaces on the inside of these tubes by lining the tubes with paper or plastic. Using such liners increases the wall thickness of the tube, thereby decreasing tuning efficiency. Other attempts have been made to provide a tube with a self threading screw surface. However, the plastic material is so hard that it cannot readily be scored by self threading tuning screws. Thus miniature inductors and transformers using ultra thin wall tubes have not been made, heretofore, on commercial scales with any degree of success.
SUBJECT MATTER OF INVENTION
The present invention provides an improved tunable inductor or the like comprising an elongated tubular member arranged with a suitable coil or coils about its outer surface and adapted to receive a threaded tuning element that extends lengthwise into the tubular member. The tubular member is formed of a suitable dielectric plastic material of hard, highly resilient plastic having a high coefficient of elasticity. Means for engaging the threads or the tuning element are formed on the inner wall of the tubular member by holes extending through the wall of the tubular member providing inwardly projecting deforming segments which project into engagement with the threads of the tuning element. In a preferred embodiment of the invention a resin, preferably epoxy, fills the holes and provides additional resistance to rotational movement of threaded tuning elements when torque is applied.
In a modification of the invention, thin wall tubes of hard plastic with a high coefficient of elasticity are permanently deformed, as described above, and filled with an epoxy. Such tubes may serve as strip-proof nuts.
An object of the present invention is to provide an improved means of securing threaded members and in particular an improved means of securing threaded members in thin walled tubes.
A further object of the present invention is to provide an improved electrical transducer having a thin wall dielectric and an adjustable component adjacent to it.
It is also an object of the present invention to provide an improved thin wall miniature tunable inductor.
A still further object of this invention is to make tunable inductors having improved tuning efficiencies by using thin wall dielectric tubes in the order of 0.001 to 0.010 inches in thickness to isolate the tuning element from the coil. Inductors with tubes of this thickness permit the close placement of the tuning element to the coils thereby significantly increasing the efficiency of the inductors.
DETAILED DESCRIPTIONS
The foregoing objects and advantages of the present invention will be more fully understood when considered in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of a tunable inductor coil embodying the present invention in greatly enlarged scale;
FIG. 2 is a cross sectional view taken along the line 2--2 of FIG. 1; and
FIG. 3 is a side elevational view of a component of the invention in modified form.
DETAILED DESCRIPTION OF INVENTION
Referring to FIG. 1 there is illustrated a tunable inductor embodying the present invention. Such tunable inductors are used for a wide range of electronic applications including, for example, use in electronic communication circuitry such as paging receivers and the like. Such inductors are normally used to tune to a particular frequency within a selected range and may, for example, be used for selectively setting different communication receivers to specifically different frequency ranges.
Because of the nature of the equipment for which such inductors are used, it is desirable to provide an inductor which has as wide a tuning range as possible. The tuning range of such devices depends in part upon the space between the tuning element and the helically wound wire coils. In tunable inductors presently in use, this distance is dependent upon the tubular member which is used to support the helical coil and contain the tuning element. Therefore it is desirable to use tubular elements which are as thin as possible. With increasing use of microelectronic circuits it has also become desirable to make these tunable inductors as small as possible. A substantial market has developed for small or miniature tunable inductors.
Significant efforts to develop appropriate tubes or tubular members for miniature tunable inductors have not been successful because the plastics that have the necessary electrical characteristics as well as sufficient strength and rigidity have deficiencies which have precluded their adoption for mass production of tunable inductors. Specifically, these plastics do not bond well to adhesives and/or have substantial memory properties. Because of these characteristics it has been difficult to provide a thread engaging inner surface on the tubular members. Attempts to crimp or dimple the tubular element on the inner surface to provide thread engaging elements have been unsuccessful. Nor do these plastic materials lend themselves to scoring by self-cutting screws. Therefore tuning elements shaped as self-cutting screws are not useful. Attempts to line the inner surface of the tubular element with a material such as paper or a soft adhesive material or resin to provide a surface in which threads can be formed have also been unsuccessful or unacceptable. In many cases the adhesives do not bond well to the plastic. In all such cases, moreover, the wall thickness of the tube is effectively increased thereby reducing the tuning effectiveness of the tube.
In the present invention there is provided an arrangement which overcomes these problems. As illustrated in FIG. 1, the tunable inductor comprises a tube or tubular member 1 appropriately insulated, conductive wire 2 and a threaded tuning member 3. The tubular member 1 is sized for the particular requirements of the electrical component, but typically may have a length of a quarter of an inch to one inch, an outer diameter of between 0.030 to 0.050 inches and a wall thickness of from 0.010 to 0.001 inches.
Tubular members of the type used in this invention are conventionally formed of plastic film having a thickness of 1 mil and wrapped to form laminations of two or three layers. As formed, these tubular members have a thickness in the order of 2 or 3 mils and are sufficiently rigid to support a helically wound wire 2. The tolerances on tubing so formed are not normally closer than ±0.0015 inches on the inner diameter. Such tunable inductors would normally be used in frequency ranges from 50KHz to 500MHz. The wire coil 2, which is conventionally wound, may have any number of turns but typically has at least a half dozen. As illustrated, the wire coil is helically wrapped about and closely engages the outer surface of the tubular member 1. The wire may have a typical size range of from 0.001 to 0.010 inches in diameter.
The tuning element 3 is formed of an electrically conductive material such as steel or iron and is normally shaped as a screw having a slotted end 4 that is adapted to permit the insertion of a screwdriver for axial movement of the tunable element 3 within the tubular member 1. Axial movement of the tunable element 3 adjusts the specific frequency of the tunable inductor. It is therefore important that axial movement of the tunable element 3 be subject to careful adjustment within the tubular member 1.
As illustrated in FIG. 2, the tunable element 3 is formed with threads 5 and has an outer diameter that preferably, in the absence of thread engaging means, provides a sliding fit with the inner diameter of the tubular member 1.
Thread engaging means are formed on the inner surface of the tubular member 1 by means of a series of holes 6. These holes 6 may be uniformly arranged such as aligned longitudinal rows, as illustrated in FIG. 1, or alternately may be randomly dispersed over the surface of the tubular element, as illustrated in FIG. 3. The holes 6 may have a range of diameters, which in the specific example illustrated, may range from 0.005 to 0.020 inches in diameter. These holes permanently deform the inner surface of the tubular member about the holes inwardly to a depth sufficient to engage the threads 5 of the tuning element 3. Typically these holes permanently deform the wall of the tubular member 1 to a distance of from 0.010 to 0.015 inches. Thus the permanently deformed portion or segment of the wall about the holes 6 provide thread engaging means for tuning elements that have an outer diameter which is less than a sliding fit.
The holes 6 are preferably formed by piercing the tubular member 3 with a sharp instrument. These perforations are made prior to the application of the wire for insertion of the tuning element. The perforations permanently stretch and distort the film which forms the tubular member 3 beyond the elastic limit so that the wall of the tubular member cannot return to its original shape. This piercing action stretches the material and apparently causes transverse tears in the shape described and illustrated in the drawings. The elongated segment 7 provide additional thread engaging surfaces. These permanently deformed segments 7 readily engage the screw threads of the tuning element 3, thus providing a suitable means for permitting threading action of the tuning element 3 without longitudinal slippage, even when longitudinal forces are applied to the tuning element 3. The permanent deformation of the tubular member formed by the holes 6 significantly increases the frictional engagement of the wall with the screw threads, making it virtually impossible to push the screws longitudinally of the tubular member. It has also been found that the perforations or holes 6 do not affect electrical performance. It should be realized that the transverse tears may be shaped so as to engage almost entirely within the thread roots. They may be positioned so that a few of them do not engage in the thread roots but he majority do. By selecting the direction and angles and spacing of the tears, it is possible to control the push through force along with the rotational torque which is required to operate the device.
As noted above, the thickness of the tubular member 1 is in the order of two or three mils in most commercial products. These tubular members have a tolerance of ±0.0015 inches on the inner diameter. The threaded tuning element normally is maintained within tolerances of ±0.003 inches. Thus by providing deformed segments of sufficient depth, adequate interference may be provided between the deformed area and the threaded tuning element to permit adequate resistance to torque in a broad range of tolerances.
In a preferred form of the invention, the tube member 2 is coated with a low viscosity epoxy. The epoxy is then wiped from the surface of the tube leaving small deposits within the holes, as illustrated at 8. The quantity of epoxy, as illustrate at 8, fills the perforation of the holes to the inner end of the segments 7, presumably by capillary action. When the epoxy solidifies it provides a firm, solid but small protrusion within the tube.
It has been found that random arrangement, or even orderly arrangement, of the holes 6 frequently results in threads cutting across the segments 7 when the tuning element 3 is inserted. This action increases the effectiveness of the holes and segments in securing the threaded tuning element 6 within the tube 1. In such arrangements the threads cut through the epoxy filled segments defining a permanent internal thread within the tubing. This arrangement has several advantages. There is provided a long-lasting permanent thread with substantial resistance to longitudinal forces. In addition, the resistance to torque is typically increased. When epoxy is used to fill the holes the resistance to torque is typically increased by a factor of four. It has been found, for example, that if an axial force is applied to a threaded tuning element and it is forced all the way through the tubular member 1, having no epoxy in the holes, it takes one and one half pounds of force. When epoxy is placed in the holes of the same tubular member, the force required to push a threaded tuning element through increases 4 times to 5 pounds.
By using epoxy as a filler for the segments 7, the number of perforations also may be reduced while retaining the same effectiveness.
In some instances it may be desirable to eliminate the epoxy 1. Under these conditions the tuning element cuts thread through the segments 7. In this arrangement the perforations or segments 7 are more resilient, resulting in lower resistance to torque, if such is desired.
The present invention also permits the amount of torque required to move the threaded tuning element 3 longitudinally to be varied. This may be controlled, as noted above, by eliminating or including the epoxy filler or alternately by varying the number and diameter of the holes 6. The number of holes will also depend in some part upon the tolerances of the components. For example, where tolerances are close, fewer holes or perforations will be needed.
In the present invention it has also been found that the rotational life characteristics of the tubular member are extremely stable. In conventional prior art tubular members used for tunable inductors, there is substantially no resistance to torque applied to tuning elements after the tuning element has been threaded into and out of the tubular member five or ten times. In short, the tubular member loses its threading capacity. In the present invention, however, the torque required to turn the tuning element in the tubular member after more than twenty five cycles is reduced only approximately 10% of its original value. After 100 rotational life cycles, the typical torque has been reduced to approximately 50% of its original value, and there is still no play in the mechanism. The part is entirely useful even at these extended life circumstances. This highly superior torque characteristic permits the present invention to be used without any appreciable wear to the tuning mechanism for fixed tuned inductors.
It has also been found that the present invention is particularly suited for general use as a strip-proof nut for a threaded element. The tubular element 1 may also be designed as a screw retaining element or as a strip-proof nut. Thus, for example, the tubular element as illustrated in FIG. 3 may be formed with means on its outer surface to permit the tubular member to function as a strip-proof nut. For example, the tubular member 1 may be formed with a wall thickness sufficient to allow it to function as a nut. With this modification, the tubular member may function as a strip-proof nut. As such, the nut is essentially strip-proof. In tests heretofore conducted a threaded member having an outer diameter substantially equal to the inner diameter of the tubular member has been forced all the way through the tubular member. After forcing it through once, the threaded member still requires 85% of the original force to drive the threaded member through once more. This means the segments 7 still function as thread engaging means. In further tests the segments 7 still function after ten passes of a threaded member through the tubular member.
It should be understood that the foregoing description of the invention is intended merely to be illustrative thereof, and other modifications and embodiments may be apparent to those skilled in the art without departing from its spirit.
|
A tunable inductor formed with a hard plastic tubular member having a low coefficient of friction. A length of wire is conventionally coiled about the outer surface of the tube or tubular member. A threaded tuning element is positioned in the tubular member. Holes formed in the wall of the tubular member each define a permanently deformed segment of the wall, with the segments projecting inwardly a distance sufficient to engage the threads of the tuning element. The thread engaging segments function as threads to engage and secure the tuning element. The holes in the wall of the tubular member are preferably filled with an epoxy plastic or the like. In a modification the tubular member is formed with deforming holes and preferably filled with cement to function as a strip proof or strip resistant nut.
| 7
|
CROSS REFERENCE
[0001] This is a continuation-in-part of U.S. patent application Ser. No. 10/336,273, filed Jan. 3, 2003.
TECHNICAL FIELD
[0002] The present invention generally relates to poultry chillers for reducing the temperature of whole birds after the birds have been eviscerated on a poultry processing line. More particularly, the invention relates to a hanger bearing assembly configured to support an auger within the poultry chiller.
BACKGROUND OF THE INVENTION
[0003] It is desirable to reduce the temperature of chickens and other type poultry after the birds have been processed, or de-feathered, eviscerated, and are otherwise oven-ready and before the birds are packaged for delivery to the retail customer. A conventional poultry chiller 10 , as shown in FIG. 1, is the “auger type” poultry chiller 10 which includes a trough-shaped, half-round tank 12 filled with ice water in which the auger 20 provides positive movement of the birds through the tank 12 . The cooling effect for the water and the bird was originally provided by crushed ice added to the water. The later prior art designs included a counter-flow recirculation of the chilled water through the tank 12 , with water being chilled by a refrigerated heat exchanger 40 instead of ice, as shown in FIG. 2. The water is introduced at one end of the tank 12 , the outlet end 16 , and flows progressively to the other end, the inlet end 14 , where it is recirculated. In the meantime, the birds are continually delivered to the tank 12 and moved under the influence of the auger 20 in the counter-flow direction, and are lifted from the outlet end 16 of the tank 12 for further processing. A prior art poultry chiller of this general type is disclosed in U.S. Pat. No. 5,868,000, and the heat exchanger for the water refrigeration system suitable for this purpose is shown in U.S. Pat. No. 5,509,470.
[0004] As noted, chilled water is added to the tank 12 at the outlet end 16 of the tank 12 , where the birds have been chilled and are being lifted out of the tank 12 . The water flows against the birds in the opposite direction of movement of the birds, thereby assuring that the birds are always flowing into the cleanest water and that there is always a temperature drop between the temperature of each bird and the temperature of the water about each bird. Typical trough-shaped tanks 12 of the chillers 10 can be 5 to 12 feet in diameter and 15 to 150 feet in length. Frequently, one or more hanger bearings 30 are provided to assist in properly supporting the auger 20 . Typically, the maximum space between hanger bearings 30 is approximately 35 feet.
[0005] As best seen in FIG. 3, the auger 20 is formed in segments and the hanger bearings 30 are located between the auger segments. A typical prior art hanger bearing 30 is supported by a horizontally extending upper structural support element 32 that is mounted at its ends to the sides of the trough and includes a downwardly depending central vertical support 33 and at its lower end an upper plate 31 . A lower plate 34 is mounted to the upper plate and together they form an internal bearing surface (not shown). Typically, the segments of the auger 20 are connected by a horizontal shaft (not shown) which is received within the bearing surface, the bearing surface being sandwiched between the upper plate 31 and the lower plate 34 , thereby transferring the weight of the auger 20 to the horizontally extending upper structural support element 32 . Typically, the diameter of the horizontal shaft is smaller than the diameter of the auger shaft 22 , thereby requiring the bearing surface of the lower plate 34 and the upper plate 3 land the vertical segment 33 of the hanger bearing 30 to be at least partially disposed between segments of the auger shaft 22 . Therefore, the distance separating segments of the auger shaft 22 is limited by the dimensions of these elements. In turn, the distance separating segments of the helical flight structure 21 of the auger 20 is also limited by the dimensions of these elements. As well, because the upper structural support elements 32 typically used to provide support to the auger 20 extend across the tank 12 within the periphery of the helical flight structure 21 , the structural elements 32 similarly dictate the separation required between independent segments of the helical flight structure 21 . Separation between segments of the helical flight structure 21 are frequently on the order of 10 inches or greater.
[0006] One of the problems of existing hanger bearings 30 is that the interruption of the helical blade structure at the intermediate bearing location impedes the forward movement of birds through the poultry chiller. Also, it is possible that some birds will move backwards in the chiller due to the counter flow of water once a bird passes by the trailing edge of a segment of the helical flight structure. Those birds that move backwards about a segment of the helical flight structure require more time than is intended to move from the inlet end to the outlet end of the trough because they traverse the same segment of the chiller more than once. The reverse movement of these birds tends to create, or increase, the size of product surges traveling through the poultry chiller. The surges result in uneven unloading of the birds at the outlet end of the chiller, causing personnel handling the birds at the outlet end of the chiller to either speed up or slow down depending upon the output of birds from the chiller. In some cases, surges can require the addition of extra handling personnel. In those instances where personnel are not available, it is not uncommon for the birds to back up in the chiller discharge chute, causing birds to spill over the sides of the chute and handling tables positioned at the outlet end of the chiller. It is possible to collect these birds prior to spill over and place them in suitable vats and storage containers. However, for those plants that do not have additional handling personnel, or that don't respond quickly enough to the surges, the birds will frequently fall to the plant floor, leading to lost product and unsanitary conditions.
[0007] Another problem with typical hanger bearings is that the relatively large spacing required between independent segments of the helical flight structure (approximately 10 inches and up) allows birds to remain in the poultry chiller after processing is complete. These birds must be removed by handling personnel prior to cleaning the poultry chiller. Removal of the stranded birds increases the time required to clean the poultry chiller, thereby increasing the down time for cleaning the chiller. As such, fewer birds can be processed through the chiller for each production run. In addition to increased time and expense associated with the clean-up process, expense is incurred due to loss of product at the hanger bearing. Longer chillers require more hanger bearings to support the auger, thereby resulting in more frequent surging and increase product loss.
[0008] From the foregoing, it can be appreciated that it would be desirable to have a hanger bearing assembly for use with a poultry chiller that permits minimum horizontal displacement between segments of the helical flight structure. As well, it would be desirable if the hanger bearing assembly permitted spacing between the segments of the helical flight structure such that birds were prevented from moving through the chiller counter to their intended direction. Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.
SUMMARY OF THE INVENTION
[0009] Briefly described, this invention involves a poultry chiller that includes a hanger bearing assembly for use in supporting a segmented auger of an auger type poultry chiller.
[0010] The novel hanger bearing assembly allows smaller gaps to be formed between the segments of the auger. The smaller gap between the auger segments reduces the tendency of birds moving from the first auger blade to the second auger blade to be deflected rearwardly in a direction counter to that intended.
[0011] Another feature is a bird deflector that is positioned at the end of a first auger blade that radially urges the birds about the hanger bearing assembly so as to avoid the birds encountering the bearing assembly and avoid the birds being hindered by the bearing assembly in their travels along the tank of the chiller.
[0012] An embodiment of the hanger bearing assembly for use in an auger type poultry chiller has an auger with a first flight and a second flight both secured about an auger shaft, the first auger flight having a first flange plate and the second flight having a second flange plate. A bearing disk is secured between the first flange plate and the second flange plate. A bearing block is disposed about the bearing disk, a lower bearing plate is secured to the poultry chiller, and the lower bearing plate has a support segment configured to receive the bearing block. An upper bearing plate is configured to receive the bearing block. The upper bearing plate is secured to the lower bearing plate, thereby maintaining the bearing block adjacent the bearing disk and securing the auger to the lower bearing plate.
[0013] An embodiment of the bird deflector is a conically shaped bird deflector positioned co-axially on the auger shaft with its smaller end portion facing the on-coming birds and the bird entrance end of the tank and its larger end portion positioned closely adjacent the auger bearing assembly to gently guide the girds about the bearing assembly.
[0014] Other systems, methods, features, and advantages of the present hanger bearing assembly will be or become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the hanger bearing assembly, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The hanger bearing assembly can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the hanger bearing assembly. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
[0016] [0016]FIG. 1 is a perspective view of a prior art poultry chiller.
[0017] [0017]FIG. 2 is a side elevation cut-away view of a prior art poultry chiller.
[0018] [0018]FIG. 3 is a top perspective view of a segment of the prior art poultry chiller shown in FIG. 2.
[0019] [0019]FIG. 4A is a cross-sectional view of a poultry chiller including an embodiment of a hanger bearing assembly according to the present invention, as viewed from the inlet end of the poultry chiller.
[0020] [0020]FIG. 4B is a partial top view of a segment of the poultry chiller as shown in FIG. 4A.
[0021] [0021]FIG. 4C is a partial perspective top view of the poultry chiller as shown in FIG. 4A.
[0022] [0022]FIG. 5A is a partial cross-sectional perspective view of the poultry chiller as shown in FIG. 4A, taken along line V-V.
[0023] [0023]FIG. 5B is a perspective cross sectional view of the circled segment of the poultry chiller shown in FIG. 5A, shown in greater detail.
[0024] [0024]FIG. 6A is a cross-sectional view of a poultry chiller including an embodiment of a hanger bearing assembly according to the present invention, as viewed from the outlet end of the poultry chiller.
[0025] [0025]FIG. 6B is a partial top view of a segment of the poultry chiller as shown in FIG. 6A.
[0026] [0026]FIG. 7 is a side view of the bearing assembly and the conical bird deflector.
[0027] [0027]FIG. 8 is a perspective view of the bearing assembly and the conical bird deflector.
[0028] Reference will now be made in detail to the description of the hanger bearing assembly as illustrated in the drawings. While the hanger bearing assembly will be described in connection with these drawings, there is no intent to limit the hanger bearing assembly to the embodiment or embodiments disclosed therein. On the contrary, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the hanger bearing assembly as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] Referring now in more detail to the drawings, in which like numerals indicate like parts throughout the several views, FIG. 4A illustrates a cross-sectional view of the poultry chiller 100 as viewed from the inlet end. The poultry chiller 100 includes a semi-cylindrical water reservoir, or tank 102 , a support member 104 connected to the tank 102 , and an auger 110 supported at opposing ends by the tank 102 .
[0030] The auger 110 is positioned longitudinally in the tank 102 . An electric motor or other conventional power means (not shown) is provided to rotate the auger 110 . The auger 110 includes an auger shaft 112 and a helical blade structure formed around the shaft 112 . As shown in FIG. 4B, the auger shaft 112 includes at least a first auger shaft segment 114 and a second auger shaft segment 116 . The helical blade structure includes a first flight segment 120 formed around the first auger shaft segment 114 and a second flight segment 122 formed around the second auger shaft segment 116 . Providing independent segments of the auger 110 in this fashion is necessitated by the need to provide support for the auger 110 at various points along its length. Support is provided to the auger 110 at the central locations by hanger bearing assemblies 140 constructed in accordance with the present invention, a preferred embodiment of which is shown in FIGS. 4A-4C. A preferred embodiment of a hanger bearing assembly 140 , according to the present invention, includes a lower bearing plate 142 , an upper bearing plate 144 , a bearing disk 150 , and an O-shaped bearing block 160 .
[0031] Referring now to FIGS. 5A and 5B, the first auger shaft segment 114 and the second auger shaft segment 116 are provided with a first flange plate 124 and a second flange plate 126 , respectively, as a means for connecting the first and second auger shaft segments 114 , 116 . In the preferred embodiment shown, the bearing disk 150 is a circular plate-like structure having a bearing surface 151 formed around its outer periphery. The bearing disk 150 is coupled between the first flange plate 124 and the second flange plate 126 using threaded fasteners, thereby securing the first auger shaft segment 114 to the second auger shaft segment 116 . Preferably, the bearing disk 150 includes a coupling aperture 152 that is arranged and configured to axially align with a first coupling recess 128 and a second coupling recess 130 disposed in the first flange plate 124 and the second flange plate 126 , respectively. Proper axial alignment of the first auger shaft segment 114 and the second auger shaft segment 116 is accomplished by disposing a coupling shaft 154 in the coupling aperture 152 as well as the first and second coupling recesses 128 , 130 . Note, the coupling aperture 152 , coupling shaft 154 , and the first and second coupling recesses 128 and 130 , merely provide assistance in adequately aligning the first auger shaft segment 114 with the second auger shaft segment 116 , and are therefore not required elements for all embodiments of the present invention.
[0032] Referring back to FIG. 4C, the lower bearing plate 142 extends radially outwardly from the auger shaft 112 toward the support member 104 that is connected to the tank 102 . The lower bearing plate 142 is secured to the support member by any adequate means, such as welding, threaded fasteners, etc. Note, the support member 104 is arranged and configured so as not to be disposed between the first flight segment 120 and second flight segment 122 , as best shown in FIG. 4A. As such, the support member 104 does not factor into the required lateral spacing between the first flight segment 120 and the second flight segment 122 . The lower bearing plate 142 includes a support segment 146 configured to receive a first half 162 of the bearing block 160 . Preferably, the support segment 146 extends beyond a vertical center line of the auger shaft 112 such that the weight of the auger 110 can be supported by the lower bearing plate 142 without the use of the upper bearing plate 144 . As such, the support segment 146 assists personnel during installation of the auger 110 into the poultry chiller 100 . However, embodiments of the hanger bearing assembly 140 are envisioned wherein the support segment 146 does not extend beyond the vertical center line of the auger shaft 112 . The second half 164 of the bearing block 160 is secured in the lower bearing plate 144 adjacent to the bearing surface 151 of the bearing disk 150 with the upper bearing plate 144 . As shown, the bearing block includes a U-shaped channel 166 to assist in positioning the bearing block 160 on the lower and upper bearing plates 142 , 144 . Preferably, the upper bearing plate 144 is secured to the lower bearing plate 142 with threaded fasteners.
[0033] Preferred embodiments of the present hanger bearing assembly 140 can include bearing disks 150 having widths of approximately two inches and lower bearing plates 142 and upper bearing plates 144 having widths of approximately one inch. Although these dimensions have been determined to provide an adequate area of contact between the bearing disk 150 and the bearing block 160 , embodiments are envisioned wherein these dimensions vary significantly. For example, these dimensions are influenced by the weight of the auger 110 that each bearing assembly 140 is required to support. Also note, as the diameter of the bearing disk 150 increases, a constant amount of contact area can be maintained although the width of the bearing disk 150 is reduced in the longitudinal direction. Reduced bearing disk 150 width translates into reduced longitudinal spacing between the first and second flight segments 120 , 122 .
[0034] A preferred embodiment is shown in FIGS. 4B, 5B, and 6 B and includes a bird deflector 175 for urging the birds radially about the auger bearing assembly 140 . As shown best in FIG. 4B, the bird deflector can be conical, is mounted on the auger shaft 114 with its axis co-axial with the longitudinal axis of the auger shaft, with its smaller end portion facing the bird entrance end of the tank and the on-coming birds, and its larger end portion placed adjacent the auger shaft bearing. The larger end portion of the conical bird deflector is substantially the same diameter or breadth as the diameter or breadth of the auger shaft bearing assembly. The bird deflector rotates in unison with the auger shaft and urges any birds moving near the auger shaft about the auger shaft bearing, avoiding any interruption of movement of the birds by the bearing. While this embodiment of the bird deflector is conical, other shapes may be used as long as they function to guide or “deflect” birds about the shaft bearing as described hereinafter.
OPERATION
[0035] As previously noted, FIG. 4A is a cross section of a poultry chiller 100 as viewed from the inlet end. As shown, the poultry chiller 100 is referred to as a right hand chiller in that the majority of birds will travel the length of the chiller down the right hand side as viewed from the inlet end. For the auger 110 configuration shown, this is achieved by rotating the auger 110 in a counter clockwise direction, as indicated by the arrow in FIG. 4A. Preferably, the hanger bearing assembly 140 is therefore disposed on the left hand side of the poultry chiller 100 to avoid impeding movement of the birds within the poultry chiller 100 .
[0036] Referring now to FIG. 6A, a cross-sectional view of a poultry chiller 100 , as viewed from the outlet end, is shown. In contrast to the poultry chiller 100 shown in FIG. 4A, the poultry chiller shown in FIG. 6A is a left handed poultry chiller, meaning the majority of birds will travel the length of the poultry chiller 100 on the left hand side, as indicated by the arrow in FIG. 6B. This is achieved by imparting a clockwise rotation on the auger 110 , the direction of rotation being determined as viewed from the inlet end. As FIG. 6A depicts a view of the poultry chiller 100 from the outlet end, the arrow appears to indicate a counter clockwise rotation. Dashed line 170 indicates a typical water level maintained within the poultry chiller 100 during operation. During operation, the surfaces of the first flight segment 120 and second flight segment 122 disposed toward the outlet end of the poultry chiller 100 make contact with the birds, thereby urging the birds toward the outlet end of the poultry chiller 100 . As shown in FIG. 6A, ideally the birds 172 remain below the surface of the water 170 during their entire transit of the poultry chiller 100 . However, it is possible that a bird 174 may be raised out of the water 170 due to frictional forces between the bird 174 and the surface of the auger 110 . In such cases, it is desirable that the bird 174 drop back below the surface of the water 170 without damage. Therefore, to prevent potentially shearing the bird between the leading edge 125 of the second flight segment 122 and the front edge 143 of the lower bearing plate 142 , the front edge 143 is both disposed to the non-poultry side of the chiller, or right hand side in the case of a left hand chiller, and angled so as not to form a scissor-like cutting surface with the leading edge 125 of the second flight segment 122 .
[0037] As shown in FIG. 6B, preferred embodiments of the present hanger bearing assembly 140 reduce the distance 127 between the trailing edge 123 of the first flight segment 120 and the leading edge 125 of the second flight segment 122 . The reduced distance 127 between adjacent flight segments 120 , 122 associated with preferred embodiments of the present hanger bearing assembly 140 ensure that the birds traveling through the poultry chiller 100 , whether above or below the water surface 170 , will not be able to travel counter to their intended direction through the chiller 100 . Therefore, preferred embodiments of the hanger bearing assembly 140 prevent both surging of the birds as well as lost product due to birds remaining in the poultry chiller 100 after operations have ceased.
[0038] The bird deflector 175 assists the smooth transition of the birds across the auger shaft bearing assembly 140 , so that the hazard of the movement of the birds travelling adjacent the auger shaft being interrupted by the bearing is reduced. The cone-shaped bird deflector is built on the upstream side of the auger shaft bearing and causes the birds to be moved outwardly from the hanger bearing mounting plates, thereby eliminating the likelihood of the birds riding the side of the auger shaft and running into the hanger bearing plate and being picked up by the end of the auger flight and flipped over the auger shaft instead of passing through the bearing area normally. The bird deflector cone is integral to the auger. The auger flight extends through the cone area and expands outwardly to substantially the same breadth as the breadth of the auger shaft bearing to guide the birds about the hanger bearing without interruption in the movement of the birds.
[0039] It should be emphasized that the above-described embodiments of the present hanger bearing assembly 140 , particularly, any “preferred” embodiments, are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the hanger bearing assembly 140 . Many variations and modifications may be made to the above-described embodiments of the hanger bearing assembly 140 without departing substantially from the spirit and principles of the hanger bearing assembly 140 . All such modifications and variations are intended to be included herein within the scope of this disclosure of the hanger bearing assembly 140 and protected by the following claims.
|
A poultry chiller 100 has a hanger 140 suspended from the upper portion of the tank 102 that supports the bearing block 160 of the auger shaft 112 between the auger blades. A conical bird deflector 175 is mounted on the auger shaft and radially deflects the birds away from the bearing block as the birds are urged across the bearing block.
| 0
|
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application 60/801,254, filed May 18, 2006. The disclosure of the prior application is considered part of (and is incorporated by reference in) the disclosure of this application.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with government support under Grant No. N66001-02-C-6023 awarded by DARPA/SPAWAR. The government has certain rights in the invention.
BACKGROUND
Speech recognition and speech translation systems receive spoken information in one language, and translate it to another language. These systems are often based on a database that has been trained using the two different languages.
SUMMARY
The present application teaches techniques for handling mixed multilingual communication in a speech recognition and translation system.
According to an embodiment, entities from outside the source language are isolated and preserved during machine translation of speech.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects will now be discussed in reference to the accompanying drawings, wherein:
FIG. 1 illustrates an embodiment where a computer runs a program that is stored on the storage media; and
FIG. 2 illustrates a flowchart of some preprocessing parts that are carried out.
DETAILED DESCRIPTION
The general structure and techniques, and more specific embodiments, which can be used to effect different ways of carrying out the more general goals, are described herein.
The present application relates to issues arising in speech recognition and speech translation systems. These systems can use text-to-text translation system, or can be systems that listen to oral communication, e.g. speech translation systems. These systems are referred to herein as being speech systems. It should be understood that speech systems include generically all of these systems.
The inventors recognized a problem that occurs in these systems. Specifically, it is not uncommon to hear multiple different languages uttered together. For example, it is not uncommon to hear an English utterance in a foreign language. The English utterances may be English names, English words, or others. Bilingual speakers may even pronounce the foreign words with the appropriate accent for the multiple languages.
Speech systems have historically assumed that the input speech is in a specified language, and compare it against corpora formed from training information. The attempt to translate may be complicated or fooled by the foreign language words.
An embodiment described herein uses language detection for increased speech recognition and speech translation. An embodiment describes processing and/or preservation of foreign language material within information to be translated.
First, a notation is described. Consider the example of a translation from an English speaker into Arabic. In the example, the English speaker is bilingual, also fluent in Spanish, and may use Spanish words within the utterance. The languages are represented notationally as follows. The primary source language or PL is English in this example, and transcription of text(P) refers to this primary source language. The secondary source language here is Spanish, referred to as SL; transcription of text(S). The target language or TL here is Arabic, and transcription of text(T).
The operation can be carried out by a programmed computer that runs the flowcharts described herein. The computer can be as shown in FIG. 1 . FIG. 1 illustrates an embodiment where a computer 100 runs a program that is stored on the storage media 105 . The program produces output through a human-computer interface 110 such as a display, sound (loudspeakers, headphones etc) or any other means. The user can interact with the program and display via a user interface which may include a keyboard, microphone, mouse, and any other user interface part materials.
In operation, the computer is programmed to carry out a speech operation. FIG. 2 illustrates a flowchart which may be a preprocessing operation for the final speech operation. These preprocessing parts may be carried out as part of the segmentation of the speech, for example.
At 200 , the system first detects words within the language that are “named entities”. The named entities may be in either the primary language or the secondary language. This detection allows the name entities to be appropriately conveyed to the target. Embodiments as described herein use proper names as the named entities; however it should be understood that other named entities can be used.
210 illustrates labeling the named entities as being separately translatable. Certain named entities, such as proper names, may be conveyed or preserved into the translated language either by re-synthesis in the translated language or by simple repetition of the primary language or secondary language after voice morphing into the translated language. In the embodiment, the names can be proper names, can be product names, they can be items which represent places, or they can simply be words in the foreign (primary or secondary source) language representing places such as city names.
The detecting and translating can be carried out as follows.
(my name is John)P becomes
(my name is)P (John)P
Translating this to the target language (P→T) yields
(my name is)T (John)P.
In this example, the word John is actually a named entity, here a name, in the primary language, and needs to stay in the primary language as part of the translation. Accordingly, the phrase is first segmented into the two parts: “my name is” first in the primary language, and “John” also in the primary language. Upon translation, the “my name is” part is translated, but “John” is maintained. The named entity may be uttered via automated speech reading, or alternatively may be recorded in the source language and replayed in the target language.
A second example includes information in both the primary and secondary languages.
(My name is Jorge)P
(My name is)P (Jorge)S
P→T
(My name is)T (Jorge)S.
In both of these examples, the “Jorge” and “John” do not have corresponding translations in the foreign language, and hence the primary language or secondary language word is kept at 230 . The remainder is translated at 240 .
If the label names have a translation in the foreign language, they are translated at 240 . An example is:
(Take this aspirin)P
(Take this)P (aspirin)P
P→T
(Take this) T (aspirin)T.
In this example, the word “aspirin”, which can be in the primary or secondary language has a translation in the foreign language. Accordingly, this translation is used.
Many times, the named entity will also have meaning as a regular dictionary word, but identifying it as a named entity will increase its translation accuracy. For example:
(He is driving an Infinity)P
(He is driving)P (an Infinity)P.
P→T
(He is driving)T (a luxury car)T
This kind of generic word for the meaning of the term in the source language may be more meaningful in the translated language. Alternatively, the original word can be retained. However, in this example, failure to identify the word “Infinity” as a named entity would likely cause it to be mistranslated, e.g., as the number infinity.
Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventor (s) intend these to be encompassed within this specification. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. This disclosure is intended to be exemplary, and the claims are intended to cover any modification or alternative which might be predictable to a person having ordinary skill in the art. For example, while the above has discussed identifying names within the phrases, it should be understood that it is alternatively possible to simply recognize any foreign word in the secondary language within the primary language during its segmentation Also, the inventor(s) intend that only those claims which use the words “means for” are intended to be interpreted under 35 USC 112, sixth paragraph. Moreover, no limitations from the specification are intended to be read into any claims, unless those limitations are expressly included in the claims. The computers described herein may be any kind of computer, either general purpose, or some specific purpose computer such as a workstation. The computer may be an Intel (e.g., Pentium or Core 2 duo) or AMD based computer, running Windows XP or Linux, or may be a Macintosh computer. The computer may also be a handheld computer, such as a PDA, cellphone, or laptop, or any other device such as a game console, a media console etc.
The programs may be written in C, or C++, or Python, or Java, or Brew, or any other programming language. The programs may be resident on a storage medium, e.g., magnetic or optical, e.g. the computer hard drive, a removable disk or media such as a memory stick or SD media, wired or wireless network based or Bluetooth based Network Attached Storage (NAS), or other removable medium. The programs may also be run over a network, for example, with a server or other machine sending signals to the local machine, which allows the local machine to carry out the operations described herein.
Where a specific numerical value is mentioned herein, it should be considered that the value may be increased or decreased by 20%, while still staying within the teachings of the present application, unless some different range is specifically mentioned. Where a specified logical sense is used, the opposite logical sense is also intended to be encompassed.
|
A translation between a source language and a target language is disclosed. The source language items are divided, with primary and secondary source language items or named entities being identified, where the primary and secondary source languages being different from each other and from the target language. The entities in the second source language are translated in a different way. For example, they may be copied into the target language, or translated in a special way that is based on their meaning, e.g, into a term that has a more descriptive meaning in the target language.
| 6
|
RELATED APPLICATION
This application claims foreign priority to European patent application 07 001 445.1 filed Jan. 24, 2007, the subject matter of which is fully incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a method of producing reflectors from glass or glass ceramics wherein a reflector being open to the outside having a closed bottom is molded in a mold at a temperature above the transformation temperature and an opening is then punched out from the bottom.
A method of that kind is known from US 2004/0264200 A1.
A reflector consisting of glass is initially produced in this case by molding a gob in a mold whereafter its bottom area is heated up locally using a burner so that an opening can then be punched out from the bottom, in the softened state of the glass, using a ram and a die. The reflector is then fire-polished to make the surface sufficiently smooth.
Alternatively, the opening in the bottom area can be produced by drilling. In that case as well, a fire-polishing step is carried out subsequently in order to produce a smooth surface.
It has been found that while a smooth surface is guaranteed in the bottom area of reflectors that have been produced according to the known method, the tolerances regarding the opening produced frequently cannot be maintained without a secondary treatment.
SUMMARY OF THE INVENTION
In view of this it is a first object of the present invention to disclose a method of producing reflectors from glass or glass ceramics which permits openings to be produced in the bottom region with sufficient precision.
It is a second object of the invention to disclose a method of producing reflectors from glass or glass ceramics which permits openings to be produced in the bottom region without any subsequent treatment.
It is a third object of the invention to disclose a method of producing reflectors from glass or glass ceramics which permits openings to be produced in the bottom region, wherein the method is suitable for a mass production.
These and other objects are achieved according to the invention by a method for producing reflectors from glass or glass ceramics that comprises the following steps:
molding a reflector being open to the outside and having a closed bottom in a mold at a temperature above transformation temperature; placing the reflector in an opening of a holder; heating up the reflector in the area of its bottom; lifting the bottom of the reflector from below using a die; punching out at least one opening from the bottom by moving at least one plunger into at least one matching opening in the die.
The object of the invention thereby is perfectly achieved.
By lifting the bottom from below using a die before the opening is punched out it is ensured that no gap can form between the bottom of the reflector and the die.
It is thus ensured that during the subsequent punching operation no glass filaments will be drawn, which otherwise could occur if small gaps were left between the reflector bottom and the surface of the die. This guarantees the precision of the opening to be punched.
According to an advantageous further development of the invention, the reflector is supported laterally on the die in the area of its bottom while the reflector is lifted by the die.
This permits the position of the opening to be punched out from the reflector to be controlled even more precisely.
According to a preferred further development of the invention the reflector is supported laterally on holding elements that project from the die in upward direction.
Having the holding elements connected with the die in this way ensures in an easy way that the reflector will automatically be supported laterally and centered as it is lifted by the die from below.
This guarantees especially correct positioning of the opening so punched out.
To the extent the reflector comprises a pot-shaped bottom, the latter preferably is held laterally, during the step of lifting the reflector by means of the die, by its contact with rod-shaped holding elements mounted on the die.
This guarantees easy and reliable support by the holding elements.
Preferably, the rod-shaped holding elements used for this purpose are carbide metal pins.
In this way, premature wear of the holding elements under the action of glass that has been heated beyond its softening point can be largely prevented.
In the step of lifting the reflector bottom by the die, the latter preferably is lifted by a small amount only, namely by an amount of between 0.1 and 3 mm, preferably between 0.1 and 2 mm, more preferably between 0.1 and 1 mm, most preferably between 0.1 und 0.5 mm.
Lifting the die by such a small amount only guarantees precise contact of the die with the reflector bottom and counteracts at the same time any instability of the reflector that may be produced by the lifting action.
According to a further embodiment of the invention, the reflector is lifted off the opening of the holder while it is lifted by the die, being merely supported on the die laterally, in the area of its bottom.
In this case, the position of the opening to be punched out from the reflector bottom is exclusively defined by the die and the holding elements connected with it so that especially high precision is obtained with respect to the position of the openings to be punched out from the reflector bottom.
According to a further embodiment of the invention, a die urges the reflector against an abutment, preferably in the form of a plate, during the lifting step.
It is possible in this way to bring the spacing between the upper end of the reflector and the reflector bottom precisely to a nominal dimension without any need for a secondary treatment, for example in the form of a grinding step. Possible tolerances are balanced out in this case in the bottom area by a minimum amount of lateral migration of the material; this is, however, not a disadvantage as larger tolerances are allowed in a direction transverse to the longitudinal axis of the reflector. Thus, the predefined tolerances are precisely adhered to in the longitudinal direction of the reflector in spite of a simplified production process.
Prior to punching out the opening from its bottom, the reflector is heated up preferably in the area of its bottom using a burner with a heating-up rate of at least 100 K/s, preferably of at least 200 K/s, more preferably of at least 300 K/s, to a temperature clearly above the transformation temperature T g at which the material is sufficiently soft to permit punching of the opening(s).
Preferably, the reflector is heated up locally in the area of its bottom to a temperature of 700 to 1000° Celsius, preferably in the range of 800-1000° Celsius, more preferably in the range of 850 to 950° Celsius, using a burner.
Depending on the composition of the glass used or the glass ceramics used, an optimum punching process is thus rendered possible without any risk of damage to the surface of the glass or the glass ceramics or any risk of glass filaments forming during the punching operation.
Following the production of the reflector by molding, the reflector preferably is removed from the mold in hot condition, for example by means of a handling device, and is placed into the opening of a holder.
Thereafter, preferably a burner, being directed against the bottom of the reflector from below, is used for heating.
Preferably, a H 2 O 2 burner is used for heating. Using a burner of that type, very targeted heating of the bottom area of the reflector can be achieved within a minimum of time, which on the one hand reduces the processing time and on the other hand prevents the reflector as such from being heated in the area of its optically effective inner surface and, accordingly, from becoming distorted.
It is understood that the features of the invention mentioned above and those yet to be explained below can be used not only in the respective combination indicated, but also in other combinations or in isolation, without leaving the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the invention will become apparent from the detailed description of preferred embodiments given with reference to the drawings. In the drawings:
FIG. 1 shows a schematic sketch illustrating the production of a reflector from a gob by a molding operation;
FIG. 2 shows a reflector in an enlarged cross-sectioned view, placed in an opening of a holder, with an associated burner intended to locally heat the bottom area;
FIG. 3 shows a sectioned view of the reflector illustrated in FIG. 2 , illustrating the next step in which the reflector is lifted from below using a die;
FIG. 4 shows a top view of the reflector illustrated in FIG. 3 , after a central opening has been punched out from the bottom; and
FIG. 5 shows a top view of an alternate design of a die with associated holding elements, designed for punching out two openings, arranged one beside the other, from the bottom of a reflector.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method according to the invention is suited for producing reflectors from glass or glass ceramics, especially such used for illumination purposes with high-energy light sources, for example for beamers or the like. As such reflectors are exposed to high thermal loading and precise tolerance control is simultaneously required, they lately have been produced from glasses or glass ceramics which in most of the cases have a thermal coefficient of expansion in the range of approximately 30-45×10 −7 /K and offer sufficient thermal resistance of up to 600° Celsius or more. After production, the inner surface of such reflectors is coated with a suitable material, such as aluminum, and can then be used for example as light-reflecting means for high-energy light sources.
The invention now discloses that opening(s) to be produced in the bottom of such a reflector are made by punching them out from the softened material, with special process control guaranteeing very precise tolerances and high surface quality.
According to the method of the invention, a reflector of this kind is initially produced from a gob by a conventional molding operation. In principle, all glass types that meet the specifications for such a reflector made from glass or glass ceramics are suited as starting material for the reflector. Generally, the transformation temperature T g is at least 550° Celsius.
FIG. 1 shows a molding device for the production of reflectors, indicated generally by reference numeral 10 , comprising a circular disk 12 in which a plurality of cavities 14 is provided and which can be rotated about a rotary axis 20 , as indicated by arrow 22 . A compression mold 16 is provided with a matching ram 18 . The compression mold 16 can be moved toward the circular disc 12 , in the direction of arrow 24 , for producing from a gob placed in a cavity 14 a glass product of the desired shape of a reflector. By rotating the circular disc 12 it is thus possible to mold a series of reflectors in the different cavities 14 of the circular disc 12 , after a gob has been placed in each of the cavities 14 using an associated handling device.
The molding operation is carried out in the known way at a temperature clearly above transformation temperature in a range where the respective glass matrix has sufficiently softened.
While during the molding operation the shape of the reflector inside can be imaged with sufficient precision so that no complex reworking of the inner surface 32 will be needed, the openings required in the bottom area cannot, however, be produced with sufficient precision during the molding operation.
The reflectors are therefore removed in still hot condition, immediately after their production, using a suitable handling device and are placed in a suitable holder 38 , as shown in FIG. 2 . The holder 38 consists of a plate 38 which is held in a supporting table 36 and is provided with an opening 40 adapted to the contour of the outer surface of the reflector 30 . In a second process step, a reflector 30 placed in the holder 38 in still hot condition is then purposefully heated from below in the area of its pot-shaped bottom 34 , using a H 2 O 2 burner 42 . The burner 42 used is one with very high burner capacity and permits the reflector to be heated up again within a very short time from a temperature in the range of approximately 500° Celsius to a red heat range, i.e. to a temperature in the order of approximately 900° Celsius, in less than one second, for example in 0.8 seconds.
Thereafter, the supporting table 36 is moved on, and the at least one opening in the bottom 34 of the reflector 30 is produced by a punching operation in a next step explained in more detail in FIG. 3 . To this end, a die 44 is urged against the pot-shaped bottom 34 from below so that the reflector is lifted by a small amount of, as a rule, between 0.1 and 1 mm.
During that operation, a plate 60 may be used as contact surface for the reflector 30 on the outside of the reflector 30 , as shown in FIG. 3 . As the reflector 30 , being lifted by the die 44 , tends to be lifted off its support in the opening 40 of the holder 38 , precise positioning of the reflector 30 is to be achieved by holding elements 46 that support the pot-shaped bottom 34 of the reflector 30 over an area 56 , preferably over approximately one third of the bottom 34 .
These holding elements 46 , being preferably designed as carbide metal pins and being directly mounted on the die 44 via supporting arms 48 , serve to laterally support and to precisely position the reflector 30 as it is lifted by the die 44 .
This guarantees precise positioning of the opening(s) to be punched out during a subsequent punching operation.
The die 44 is provided with one or more opening(s), corresponding to the opening(s) in the reflector bottom to be punched out, and a punching section 54 of one or more associated rams 52 can be run down into each of such openings for punching out the opening or the openings from the bottom 34 of the reflector 30 .
The punching operation is effected using a die 44 of carbide metal having a sharp-edged punching section 54 . A certain play of a few tenths of a millimeter is used between the punching section 54 and the associated opening 50 of the die 44 . The contact between the upper end of the reflector 30 and the plate 60 as the die 44 is lifted from below guarantees that a precise dimension is maintained between the upper end of the reflector 30 and the lower end of the reflector bottom 34 , as the material, having been softened before, will yield laterally to balance out any deviation. At the same time, this arrangement contributes toward exactly positioning the reflector 30 . Further, pressing the die 44 against the reflector bottom 34 from below ensures that no glass threads will be formed during the punching operation.
If necessary, the die 44 and/or the ram 52 may be cooled in addition.
In the arrangement illustrated in FIG. 3 , holding elements 46 are arranged one opposite the other so that a total of four holding elements are provided.
Alternatively, it is also possible, for example, to use three holding elements 46 a arranged in triangular configuration, as shown in FIG. 5 . FIG. 5 shows a top view of a correspondingly designed die 44 a in which three carbide metal pins serving as holding elements 46 a are arranged in triangular configuration. Contrary to the die 44 shown in FIG. 3 , the die 44 a comprises two openings 50 a so that two openings arranged one beside the other can be punched out from the bottom 34 of the reflector 30 in one punching operation.
FIG. 4 shows a top view of the reflector 30 after one opening 50 has been punched out from the bottom 34 .
It is understood that the form of the reflector 30 shown in the drawing is given by way of example only and that the method according to the invention can be used irrespective of the form of the respective reflector 30 .
Further, the method according to the invention is largely independent of the type of material used for the glass or glass ceramics, provided the operation is carried out in a suitable temperature and/or viscosity range.
|
The invention provides a method of producing reflectors from glass or glass ceramics comprising the steps of: molding a reflector being open to the outside and having a closed bottom in a mold at a temperature above the transformation temperature; placing the reflector in a recess of a holder; heating up the reflector in the area of its bottom; lifting the bottom of the reflector from below using a die; punching out at least one opening from the bottom by moving at least one plunger into at least one matching opening in the die.
| 2
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.