Abstract:
A modular drive unit for controllably extending a storage receptacle such as a drawer or shelf, wherein the drive unit comprises a drive pulley, a take up pulley and an elongate spring member biased such that the spring member has a tendency to wind about one of the take up pulley and the drive pulley. The modular drive unit further includes a drive wheel rotatably coupled to the drive pulley, a rotation thereof providing a drive force for extending of the storage receptacle. The drive wheel includes either or both of a toothed gear wheel and a cylindrical shaft for receiving a drive cable windable thereon.

Description:
TECHNICAL FIELD  
       [0001]     The present invention relates generally to actuating mechanisms for opening or closing drawers or other receptacles, extending shelves and the like, and relates more particularly to such a mechanism for actively driving the extension of a drawer or shelf, the mechanism having a push latch and at least one spring motor operable to extend the drawer or shelf via a cable or gear system.  
       BACKGROUND OF THE INVENTION  
       [0002]     Various means for driving opening and/or closing of cabinet drawers, shelves, and various types of storage racks have long been known in the art. For example, various spring-loaded cash registers and tool drawers are known. In one typical design, an operator pushes a button, electronically or mechanically actuating a release mechanism, allowing extension of a drawer, shelf or similar storage receptacle under the action of a spring. Although such designs have been shown to be useful in certain applications, they tend to be relatively bulky and require complex and expensive retrofitting of structures to which they are applied. Moreover, many examples of such devices require manual actuation of a switch, button, latch or similar mechanism. In certain environments, manual manipulation of switches, handles, etc. can provide a significant risk of bacterial and/or chemical contamination. It is thus desirable to provide an actuating mechanism that overcomes one or more of the problems or shortcomings set forth above.  
       SUMMARY OF THE INVENTION  
       [0003]     It is an object of the present invention to provide a drive system for a reciprocable unit that allows hands-free opening and closing.  
         [0004]     It is a further object of the present invention to provide a modular drive system for a drawer or similar unit.  
         [0005]     The present invention comprises a drive system for extending a reciprocable unit, e.g. a drawer, shelf, bin, cassette, tray, or similar member. The drive system is preferably housed at least partially within a modular housing unit, and preferably includes a plurality of spring motor drive units. In one preferred embodiment, the modular housing is mounted to a frame that houses the reciprocable unit. In another preferred embodiment, the spring motor drive units actuate the drawer by rotating a toothed gear wheel that meshes with a complementary gear rack, preferably attached to the drawer. In another preferred embodiment, the spring motor actuates the drawer by winding a cable, preferably attached to the drawer about a central armature. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIGS. 1 and 1   a  illustrate top and side views, respectively, of a drive module according to a preferred embodiment of the present invention;  
         [0007]      FIG. 2  illustrates a drive module according to a preferred embodiment of the present invention engaged with a gear rack;  
         [0008]      FIG. 2   a  illustrates a schematic side view of a mounted drive module according a preferred embodiment of the present invention;  
         [0009]      FIGS. 3 and 3   a  illustrate top views, respectively, of a grooved gear wheel according to a preferred embodiment of the present invention;  
         [0010]      FIGS. 4 and 4   a  illustrate top and side views, respectively, of a drive module according to a preferred embodiment of the present invention;  
         [0011]      FIG. 5  illustrates a top view of a drive module similar to  FIG. 4 ;  
         [0012]      FIGS. 6   a - d  illustrate various top and side views of a latch and pulley module according to a preferred embodiment of the present invention;  
         [0013]      FIG. 7  illustrates a combination drive module and latch-and-pulley module according to a preferred embodiment of the present invention;  
         [0014]      FIGS. 8 and 8   a  illustrate top and side views, respectively, of drive module according to a preferred embodiment of the present invention;  
         [0015]      FIG. 9  illustrates a side view of a drive module according to a preferred embodiment of the present invention;  
         [0016]      FIG. 10  illustrates a combination drive module and latch-and-pulley according to a preferred embodiment of the present invention;  
         [0017]      FIGS. 11 and 11   a  illustrate top and side views, respectively, of a drive module according to a preferred embodiment of the present invention;  
         [0018]      FIG. 12  illustrates a drive module in combination with a plurality of pulley modules according to a preferred embodiment of the present invention;  
         [0019]      FIGS. 13   a - c  illustrate top, front and side views, respectively, of a bullet-nose pulley device according to the present invention;  
         [0020]      FIGS. 14   a  and  14   b  illustrate side and top views, respectively, of a catch mechanism according to the present invention;  
         [0021]      FIG. 15  illustrates a front view of a bullet-nose pulley device having a ring thereon, according to the present invention;  
         [0022]      FIGS. 16   a - 16   d  illustrate serial positions of a catch mechanism similar to  FIGS. 14   a  and  14   b  engaging a pulley device similar to  FIG. 15 ;  
         [0023]      FIG. 17  illustrates a drive module engaged with a rack and slide assembly according to a preferred embodiment of the present invention;  
         [0024]      FIG. 18  illustrates a drive module utilizing a pulley and slide assembly according to a preferred embodiment of the present invention;  
         [0025]      FIG. 19  illustrates an alternative embodiment of the invention of  FIG. 18 ;  
         [0026]      FIG. 20  illustrates an alternative embodiment of the invention of  FIG. 18 ;  
         [0027]      FIG. 21  illustrates a drive module according to an alternative embodiment of the present invention;  
         [0028]      FIG. 22  illustrates a vehicle storage receptacle for use with a modular drive unit according to a preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0029]     Referring to  FIGS. 1 and 1   a , there are shown top and side views, respectively, of a gear drive module  10  according to a preferred embodiment of the present invention. Module  10  includes a housing  12 , preferably formed from sheet steel but also possibly of plastic or another suitable material, within which a spring motor  11  is positioned. Spring motor  11  is preferably a conventional constant force spring motor having two take up pulleys  14   a  and  14   b , however, a variable force spring motor such as a watch spring, or a greater or lesser number of pulleys might be used without departing from the scope of the present invention. Each take up pulley  14   a  and  14   b  preferably includes a spring  16  wound around and anchored to a center armature  18  of a main drive pulley  20 . Main drive pulley  20  preferably includes a drive wheel  22  populated with a plurality of teeth  26 . In a preferred embodiment, a rotary damper  30  is positioned adjacent main drive pulley  20 , and has a toothed damper wheel  32  engaging drive wheel  22 . Rotary damper  30  is preferably a conventional rotary damper that dampens the rotation of main drive pulley  20  in a first direction, but does not damp the rotation of pulley  20  in the opposite direction, i.e. a winding direction as explained below. If desired, a dual-directional damper might be used without departing from the scope of the present invention. All the component parts of the present invention are manufactured by known methods and by known materials.  
         [0030]     Referring now to  FIG. 2 , there is shown module  10  of  FIG. 1  with gear teeth  26  of drive wheel  22  meshed with teeth on an elongate gear rack  36 . In a preferred embodiment, module  10  is mounted under the subject drawer or bin, etc., and gear rack  36  is mounted to the drawer itself. It should be appreciated, however, that the mounting configuration could be reversed without departing from the scope of the present invention. For instance, embodiments are contemplated in which module  10  is mounted to the drawer itself, and the gear rack  36  is mounted to the frame housing the drawer. Those skilled in the art will appreciate that the term “drawer,” and the appurtenant descriptions herein, are intended to refer to any structure such as a drawer, bin, shelf, slide, cassette, tray, etc. to which the present invention might find application. A latch mechanism  40  is mounted to housing  12 , actuation of which initiates unwinding of the springs  16  and rotation of the spring motors  14  to drive the associated drawer (described below) to an open position, preferably limited in speed by damper  30 . The latch mechanisms preferably used in combination with the present invention are “push-push” latches, well known in the art. Such latches are pushed to disengage, and pushed to engage. Referring to  FIG. 2   a , there is shown a side view of unit  10  mounted in a housing assembly  11 . In the embodiment pictured in  FIG. 2   a , modular unit  12  is mounted in an interior of housing assembly  11 , proximate the side from which a drawer  70  extends. When an operator pushes against drawer  70  (when closed), latch  40  disengages, allowing unit  12  to extend drawer  70  to an open/extended position. When closing of drawer  70  is desired, the operator can push against drawer  70 , driving it back toward a stored position, at which it re-engages latch  40 . Manually returning drawer  70  to its stored position re-energizes the drive unit by unwinding coil springs  16  from their respective pulleys  14 , and winding the springs onto the drive pulley  20 .  
         [0031]      FIG. 3  illustrates an alternative configuration for a drive pulley wheel  50  for use with the above embodiment (as well as others), particularly for use where the associated drawer is removable. Pulley wheel  50  has a substantially spiral groove  52 , into which a slide-bracketed pin  54  extends. Pin  54  is slidably mounted in a bracket  56 , and thus slidably reciprocates along bracket  56  due to rotation of wheel  50 . When wheel  50  is rotated in a first direction (counter clockwise in  FIG. 3 ), pin  54  traverses groove  52  until it reaches a first end  58  of groove  52  or, preferably, until it bears against a physical stop (not shown) affixed to bracket  56  and preferably spanning the slot  56   a  within which pin  54  slides. When wheel  50  is rotated in a second direction (clockwise in  FIG. 3 ), pin  54  traverses groove  52  until it reaches a second end  59  of groove  52 . In alternative embodiments (not shown), a stop might be attached to bracket  56  at both ends of the path traversed by pin  54 , limiting vertical travel of pin  54 , and thus rotation of wheel  50 , in both directions. By selecting the proper groove length, the groove and slide-bracketed pin allows rotation of wheel  50  to be limited in either or both directions such that wheel  50  does not rotate far enough under influence of its associated coil springs (not shown in  FIG. 3 ) that they become disengaged when the drawer unit is removed from its housing.  FIG. 3   a  illustrates a side view of wheel  50  with bracket  56  and pin  54 . In a preferred embodiment, bracket  56  is mounted to the module housing. The length of the spiral path traversed by pin  54  might be varied according to the distance of drawer reciprocation desired; for example, a larger number of spirals (tighter spiral) allows wheel  50  to rotate further before pin  54  reaches the end of groove  52 , corresponding to a greater length of spring that may be wound around armature  18 . Conversely, a smaller number of spirals (broader spiral path) traversed by pin  54  corresponds to lesser rotation and a lesser length of spring wound around armature  18 .  
         [0032]     Referring now to  FIG. 4 , there is shown a top and an end view of another alternative embodiment of a module  60  similar to the module of  FIG. 1 . Module  60  differs from the  FIG. 1  embodiment, however, in that a cable  62  is utilized to drive the drawer, rather than an interface with a gear rack. In a preferred embodiment, cable  62  has one end secured to a body  64  of the main drive pulley  66 , and a second end secured to the drawer  70 , as shown in  FIG. 5 . When opening of the drawer is initiated, drive pulley  66  is rotated in a manner similar to that described with respect to the  FIG. 1  embodiment. Thus, spring-driven rotation of drive pulley  66  winds cable  62  around drive pulley  66 , pulling the drawer to an extended position. A unidirectional damper  68  is also preferably included with module  60 , controlling the speed of extension of the drawer.  
         [0033]     In the embodiment depicted in  FIGS. 4 and 5 , cable  62  extends substantially in the same direction in which the module/associated drawer travels during opening and closing, however, alternative configurations are contemplated. For certain applications, for instance, where the cable drive unit is considered too large to mount in the front of a cabinet, it may desirable to mount the cable drive mechanism of  FIG. 4  at the rear of the cabinet. In this embodiment, the cable is redirected through a pulley to ultimately pull the drawer in the desired direction.  FIG. 6  illustrates several views of a combination pulley-latch pin device  80  that properly locates the push latch mechanism, and also redirects the force from the cable.  FIG. 7  is a module similar to the module from  FIG. 4 , in combination with device  80  of  FIG. 6 , illustrating the relative direction of travel of the cable  62 .  FIG. 8  illustrates yet another embodiment  100  in which the opening force is redirected by redirecting travel of the cable. In module  100 , a roller assembly  110  is attached to the module housing, and redirects the cable travel substantially 90°. In this embodiment, the module  100  may be mounted at a right angle to the direction of pull force on the associated drawer.  FIG. 9  illustrates module  100  and the associated cable extended.  FIG. 10  illustrates module  100  in combination with a pulley-latch pin device similar to device  80 . Thus, in the  FIG. 10  embodiment, the cable is initially directed through roller  110 , and then redirected once more through device  80 .  
         [0034]     Referring to  FIG. 11 , there is shown yet another embodiment of the present invention  200 , utilizing a dual cable system. It is contemplated that this embodiment will find particular application where the cable drive must move relatively heavy loads, for instance, a tool drawer weighing a hundred pounds or more when loaded. Heavier drawers have the tendency to “bind” if they are pulled asymmetrically, and it is thus desirable to attach multiple cables at or near the corners of the subject drawer. Module  200  has a first cable  262  and a second cable  264  that are extendible from the module housing  201  in substantially opposite directions. In a preferred embodiment, cables  262  and  264  are redirected through a pair of pulleys  272  (as shown in  FIG. 12 ), and attached to the drawer, which they can move in a fashion similar to that described with respect to the foregoing embodiments. Various modifications to the dual drive embodiment disclosed herein might be made. For instance, the cables might be oriented differently. One cable might extend directly to the rear of the drawer, with the other cable extended at a right angle before being redirected to the rear of the drawer. Similarly, the cables might extend initially in a substantially forward direction (parallel to the drawer travel direction), then be redirected 180° to the rear of the drawer.  
         [0035]     Referring now to  FIGS. 13   a ,  13   b , and  13   c , there is shown a catch mechanism  300 , particularly for cable drive applications in which it may be desirable to remove the drawer. Catch  300  includes a body piece  301  having a groove  304 , and a mounting plate  302  with apertures  305  for receipt of a fastener such as a screw. A pulley  303  is mounted in body  301 , and is preferably substantially aligned with groove  304 . In a preferred embodiment, catch  300  is mounted at or near the front of the drawer/bin frame.  FIGS. 13   a ,  13   b , and  13   c  show top, front, and side views, respectively, of catch mechanism  300 .  FIGS. 14   a  and  14   b  illustrate side and bottom views, respectively, of a hook mechanism  310 . Hook  310  includes a hook plate  312  that is preferably mounted directly to the underside of the subject drawer. A plurality of holes  314  are preferably punched in plate  312 . In a preferred embodiment, the holes are punched such that they leave barbs  315  along the side of plate  312  where the punching tool exits. The protruding barbs assist in preventing slippage between plate  312  and the drawer to which it is attached. Fasteners are preferably used in conjunction with a plurality of apertures  316  in plate  312  to fasten hook plate  312  to the associated drawer. Hook  310  also includes a protruding hook member  317 , preferably extending downward from plate  312 .  
         [0036]     Referring to  FIGS. 16   a - d , there are shown sequentially arranged views of catch  300  engaging hook  310 . As described, hook  310  is preferably affixed to a drawer  320 , while catch body  301  is affixed to a drawer frame (not shown).  FIG. 16   a  illustrates the two components as they would preferably appear with drawer  320  removed from its stored position. In a preferred embodiment, hook plate  310  and catch  300  are preferably mounted such that hook member  317  is aligned with groove  304 , shown in a front view, as in  FIG. 15 . As drawer  320  is moved toward the drawer frame, hook member  317  becomes engaged with groove  304 . Further movement of drawer  320  brings hook member  317  into engagement with a ring member  330  fitted over the nose of body piece  301 . As hook member  317  engages ring member  330 , and passes beyond groove  304 , hook member  317  draws ring member  330  off the nose of body piece  301 . Ring member  330  is attached to the cable used to drive the drawer  320 , and is thus held under spring tension against the nose of body piece  301 . Thus, as the drawer is moved inward, ring  330  draws the attached cable through groove  304  and across pulley  303 , winding the associated drive pulley at the opposite end of the cable, and tensioning the drive spring(s). When removal of the drawer is desired, the operator can actuate the drawer toward its extended position, and manually pull the drawer out of its frame. When hook member  317  passes body piece  301 , spring tension draws the cable through groove  304  and, consequently, draws ring  330  snugly against the nose portion of body piece  301 , thereby preventing the cable from retracting into the module. The preferably bullet-nose shape of the nose portion of body piece  301  facilitates centering of ring  330 , leaving it in the proper position to be engaged by hook member  317  upon reinsertion of the drawer.  
         [0037]      FIG. 17  illustrates an embodiment of the invention in which a slide mechanism serves as a platform upon which the drawer is mounted. In particular, the  FIG. 17  embodiment includes a dampened gear drive assembly  400  similar to that described with respect to the embodiment pictured in  FIG. 1 . This embodiment also includes an elongate gear rack  436  mounted on a carriage  410 . Because the drive assembly  400  is mounted externally of the animated carriage, a longer extension is possible than in embodiments utilizing a drive module positioned beneath the animated unit. Carriage  410  can be mounted on rollers, low-friction sliding members, or any other suitable means by which it can smoothly reciprocate within the frame. In a preferred embodiment, the actual drawer, bin, etc. can be mounted directly on top of carriage  410 .  FIG. 18  illustrates yet another embodiment, in which a cable drive assembly  500  is mounted externally of a carriage  510 , the direction of cable travel being redirected through a pulley  520  preferably mounted on the carriage itself. In the embodiment pictured in  FIG. 18 , a damper  530  is in cooperation with the cable drive assembly  500 , but is mounted such that its gear teeth  532  mesh with a gear rack  536  attached to carriage  510  inboard of the slide assembly.  
         [0038]      FIG. 19  shows yet another embodiment of the present invention, in which a cable drive assembly  600  similar to that disclosed with respect to  FIG. 18  is employed. The  FIG. 19  embodiment differs, however, in that the cable drive assembly  600  is mounted at the rear of the carriage  610 . The cable travel, and thus the pull force, is redirected 180° through a pulley  620 .  FIG. 20  is yet another iteration of the present invention, utilizing a cable drive module  700  and carriage  710 . The  FIG. 20  version is similar to the  FIG. 19  embodiment, but employs two pulleys  720  and  721 , allowing the cable travel and opening force to be redirected a second time. This embodiment allows the drive unit  700  to be mounted at the rear of carriage  710 , but at approximately 90° from the direction of travel.  
         [0039]     Turning now to  FIG. 21 , there is shown yet a further preferred embodiment of the present invention. The  FIG. 21  embodiment provides a drive module  810  wherein an adjustable “clock” spring  815  is positioned within a rotatable armature  813 . Spring  815  is preferably a standard power spring or clock spring in which energy is stored by winding it around armature  813 . A first end of spring  815  is preferably fixed to an inside of armature  813 , whereas a second end of spring  815  is fixed to a shaft assembly  817 . The drive means for drive module  810  is thus preferably embedded in the center of the rotatable drive apparatus that drives the module, allowing the drive motor and entire module to be substantially smaller than embodiments utilizing multiple drive and/or take up pulleys. The module design further provides a choice of gear drive or cable drive applications. Thus, drive module  810  preferably includes a toothed drive wheel  820 , as well as a cylindrical outer surface on which a cable (not shown) may be wound.  
         [0040]     Drive module  810  further provides for an adjustable force of spring  815 . Shaft assembly  817  preferably comprises a head portion  819  having a shaped recess  821  in a first end thereof. Shaft assembly  817  is further reciprocable between a first position and a second position, and is preferably biased toward its second position with a wave spring  823  positioned between head portion  819  and a housing  811 . At the shaft assembly&#39;s second position, as shown in  FIG. 21 , a preferably threaded member  809  is engaged with a protrusion  830 , preferably attached to or integral with housing  811 . In a preferred embodiment, a notch, groove or other similar feature is formed in member  809 , and engages protrusion  830  in a substantially mating fashion. Various threaded members such as nylock type nuts or jam nuts may be used, preferably minimizing relative rotation between the threaded portion of shaft assembly  817  and the nut. A mating there between fixes shaft assembly  817  against rotation relative to housing  811 .  
         [0041]     It should be appreciated that alternative means for fixing shaft assembly  817  might be utilized, so long as the assembly is rotatable at a first position, and fixed against rotation relative to the housing at a second position. By disengaging shaft assembly  817  from its fixed position relative to housing  811 , i.e. by overcoming wave spring  823  and moving shaft assembly  817  axially such that member  809  disengages with protrusion  830 , shaft assembly  817  may be rotated relative to armature  813 , increasing or decreasing a tensioning of spring  815 . Shaped recess  821  facilitates rotation of shaft assembly  817  by allowing engagement with an adjustment tool such as a screwdriver, hex or torx wrench, etc. (not shown). The degree of spring adjustment depends on the number of rotations of shaft assembly  817  relative to armature  813 . When downward pressure is released from shaft assembly  817 , the force of wave spring  823  causes threaded member  809  to re-engage with protrusion  830 .  
         [0042]     Drive module  810  is preferably mounted in any suitable configuration in cooperation with a drawer, cassette, etc. as discussed relative to the foregoing embodiments. Thus, those skilled in the art will contemplate a great variety of cable and gear drive designs suitable for application of drive module  810 . When the associated “drawer” is pushed closed, spring  815  is preferably energized, i.e. wound in a direction against its inherent spring bias. Various push-push latches, as described herein, may be utilized in conjunction with drive module  810 .  
         [0043]     The present description is for illustrative purposes only, and should not be construed to limit the breadth of the present invention in any way. Thus, those skilled in the art will appreciate that various modifications might be made to the presently disclosed embodiments without departing from the intended spirit and scope of the present invention. For instance, rather than being used to drive a drawer unit in a substantially linear fashion, as is conventional with drawers, slides, trays, etc., the present invention might be adapted for use as a rotational drive system. The modular unit described with respect to  FIG. 1  might be adapted to rotationally drive a unit, for example, by affixing a rounded rather than linear gear rack to the unit to be driven. This application might be useful for driving a rotating shelf unit such as a “Lazy Susan.” Further, rather than a gear interface, the cable drive units, for instance those described with respect to  FIG. 4 , might be adapted for use with a rotating structure.  
         [0044]     Still further designs are contemplated, including, for example, tie racks, shoe racks and similar devices might all benefit from the use of the present push-push controlled drive mechanism. Other contemplated applications include automobile storage containers such as tape or CD trays. In one such embodiment, a modular unit such as the molded plastic unit shown in  FIG. 22  is fitted with any of a variety of drive modules, as described herein. Further modifications to the plastic drive unit of  FIG. 22  might include integrally molded gearing features such as a gear rack molded as part of the original module. In these contemplated embodiments, a push-push latch similar to those previously described might be utilized. Other aspects, features and advantages of the present invention will be apparent upon an examination of the attached drawing figures and appended claims.