Patent Publication Number: US-2009223133-A1

Title: Self Locking Lifter Plate

Description:
This application claims the benefit of U.S. Provisional Application No. 61/034,603 filed Mar. 7, 2008 and entitled “Self Locking Lifter Plate”. 
    
    
     FIELD OF THE INVENTION 
     The invention generally relates to the field of automotive window regulators, and more specifically to the art of connecting a glass panel to the operating structure of a window regulator. 
     BACKGROUND OF THE INVENTION 
     In vehicles, the window regulator actuates a glass panel to and fro, typically between a closed position where the glass panel functions as a door window and a closed position where the panel is retracted at least partially within the cavity of a door structure. The glass panel is attached to the window regulator through one or more lifter plates. These lifter plates are generally attached to the glass panel through a secondary operation, where, for instance, a fastener is used to lock in a clamp or to attach to a feature bonded onto the glass gas panel. In some cases the glass panel may be attached without this secondary operation, but these designs typically utilize a pin feature that attaches to the glass through a hole that was previously drilled in the glass. It would be desirable to have a self-locking lifter plate that attaches to the glass panel without requiring a secondary operation or require a hole drilled through the glass panel. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention a clamping assembly is provided for connecting a glass panel to a window regulator. The assembly has a liner for gripping opposing sides of the glass panel. A holder, which is connectable to the window regulator, has a channel for seating the liner. At least one of the liner and the holder channel has sloping walls so that the gripping pressure of the holder and liner against the glass panel increases the deeper the liner sits in the holder channel. The liner includes an array of sloping teeth and the holder includes an array of sloping teeth, the liner teeth and holder teeth inter-engaging one another to form a ratcheting mechanism that enables the liner to travel in only one direction, deeper into holder. 
     In preferred embodiments a detent mechanism limits the travel of the liner into the holder until a specified force is applied to the liner in the direction of the holder channel. This force is achieved when the weight of the glass panel is brought to bear against the liner, which will occur only when the glass pane is fully seated in the liner. Thus, the liner will not move into the clamping portion of the assembly until the glass panel is completely seated in the liner, thereby ensuring the proper engagement between the glass panel and the liner. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described, by way of example only, with reference to the attached Figures, wherein: 
         FIG. 1  is perspective view of a self-locking lifter plate assembly according to a first embodiment of the invention; 
         FIG. 2  is side view of the assembly shown in  FIG. 1 ; 
         FIG. 3  is an isolated perspective view of a liner employed in the first embodiment; 
         FIG. 4  is an isolated perspective view of a holder employed in the first embodiment; 
         FIG. 5  is perspective view of a self-locking lifter plate assembly according to a second embodiment of the invention; 
         FIG. 6  is a cross-sectional view of the assembly shown in  FIG. 5 , taken along line VI-VI therein; 
         FIG. 7  is an isolated perspective view of a liner employed in the second embodiment; 
         FIG. 8  is an isolated perspective view of a holder employed in the second embodiment; 
         FIG. 9  is an isolated perspective view of a locking clip employed in the second embodiment; and 
         FIG. 10  is a partially assembled view of the second embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A first embodiment of a self-locking lifter plate assembly  10  is shown in  FIGS. 1-4 . Referring to these drawings, the assembly  10  includes two main parts, a liner  12  (shown in isolation in  FIG. 3 ) that contacts a glass panel  16  and a holder  14  (shown in isolation in  FIG. 4 ) that retains the liner  12 . The liner  12  is seated in the holder  14  in such a manner so as to generate a self-adjusting clamping force on the glass panel  16 . To ensure the clamping force is maintained the liner  12  is mechanically limited in its direction of travel and allowed to travel only in a direction in which the clamping force increases. 
     More particularly, the liner  12  is preferably manufactured from a relatively rigid plastic material with a much softer over-molded wrapper portion  18  (such as gripping foam) that directly warps around and contacts a portion of the glass panel  16 . The liner includes a U-shaped upper portion having opposing walls  20 ,  21  that flank the wrapper portion  18 . The walls  20 ,  21  are connected by an adjoining base portion  22  of the liner and a living hinge  24  is provided between the walls  20 ,  21  and the adjoining base portion  22  so as to allow the walls  20 , 21  to flex inwards and outwards relative to one another. 
     A shaft  26  extends from the base portion  22 . The shaft  26  has at least one planar face and preferably two opposing planar faces each featuring an array of upwardly sloping teeth  28  formed therein. 
     The holder  14  is also preferably molded from a relatively rigid plastic and includes a seat  30  for retaining the U-shaped upper portion of the liner  12 . The seat  30  has two opposing walls  31 ,  32  which, in side view, are sloped so as to provide a wedge or V-shaped channel  34  in the seat  30 . Thus, the deeper the liner  12  is inserted into the holder  14  the greater the clamping force on the glass panel  16 . 
     The base of the seat  30  also includes an aperture  36  for passage of the liner shaft  26  therethrough. The liner shaft  26  interacts with a clip  38  that depends from one of the walls  31 ,  32  of the holder  14 . The clip  38  has a protrusion  40  that features an array of teeth  42  that are sloped opposite to the teeth  28  present in the planar face of shaft  26 . The clip  38  and its protrusion  40  are disposed to engage and interact with the shaft  26  such that the shaft teeth  28  and protrusion teeth  42  provide a ratcheting mechanism, enabling the liner  12  to only travel in only one direction-deeper into the seat  30 . The ratcheting mechanism allows some deflection so that the liner teeth  28  and the holder teeth  42  can pass over each other, but only in a single direction, in the opposite direction the teeth are designed to lock. The clip  38 , by virtue of its shape (having elongate depending arm  44  and curved connecting portion  46 ), is however somewhat resiliently flexible and may be manually urged away from its locking position to release the liner shaft so that the glass panel may be pulled out of the assembly  10  for vehicle servicing and the like. 
     In operation, the liner  12  is initially only partially seated in the holder  14 , so that the ratcheting mechanism is able to prevent the components from separating from one another. In this initial installation position, a mechanical detent provided by flexibly resilient holder tangs  48 , which project inwardly from the walls  31 ,  32  into channel  34 , and liner side projections  50  limits the travel of the liner  12  into the holder  14  until a specified threshold force is applied. This force is achieved when the weight of the glass panel  16  is brought to bear against the liner, which will occur only when the glass pane  16  is fully seated in the liner  12 . Thus, the liner will not move into the clamping portion of the assembly until the glass panel is completely seated in the liner, thereby ensuring the proper engagement between the glass panel and the liner. When the window regulator (not shown in its entirety) is actuated to drive the glass pane  16  into its closed position, the window regulator will drive the holder  14  against the held-in-position glass pane  16 , thus fully seating the liner  12  and glass panel  16  in the holder  14 . Any subsequent slack between the liner  12  and the glass panel that may later occur due to settling of the components or wear and tear will be taken up in due course as the window regulator is routinely operated and the liner  12  is forced deeper into the holder  14 . 
       FIGS. 5 and 6  show a second embodiment of a self-locking lifter plate assembly  100  in perspective and cross-sectional views, respectively. Referring to these assembly drawings and  FIGS. 7 ,  8  and  9  which various components in isolation, the assembly  100  includes three main components, a U-shaped liner  112  ( FIG. 7 ) that contacts the glass panel, a holder  114  ( FIG. 8 ) that seats the liner  112 , and a locking clip  116  ( FIG. 9 ). 
     The liner  112  is preferably manufactured from a relatively rigid plastic material and has a much softer wrapper portion  118  (such as gripping foam) that directly wraps around and contacts a portion of the glass panel. The U-shaped liner  112  has opposing walls  120 ,  121  that flank the wrapper portion  118 . The walls  120 ,  121  are connected by an adjoining base portion  122  of the liner and living hinges  124  are provided between the walls  120 ,  121  and the adjoining base portion  122  so as to allow the walls  120 ,  121  to flex inwards and outwards relative to one another. 
     The outer face of each of the holder walls  120 , 121  feature an array of upwardly sloping teeth  128  formed therein. The liner  112  and its teeth  128  form a first portion of a ratchet mechanism. 
     The holder  114  is also preferably molded from a relatively rigid plastic and includes a seat  130  for retaining the U-shaped liner  112 . The seat  130  has two opposing walls  131 ,  132  which, in side view, are sloped so as to provide a wedge or V-shaped channel  134  in the seat  130 . Thus, the deeper the liner  112  is inserted into the holder  114  the greater the clamping force on the glass panel. 
     Referring additionally to a partially assembled view of the assembly  100  in  FIG. 10 , the holder  114  provides a second part of the ratchet mechanism. In the second embodiment the holder  114  includes two pads  140 . Each pad  140  has a planar face  142  featuring a plurality of teeth  144 . On the sides of each pad, a serpentine groove  146  is formed in the body of each pad  140 . The pads  140  are connected to the holder  114  via flexible straps  148  that are integrally formed with the holder  114  and project from the top edges thereof. 
     In assembly, the pads  140  are folded into apertures  150  (seen best in  FIG. 8 ) located in the sidewalls of the holder  114  so that the teeth  144  face inwardly into the holder to mate with the liner teeth  128 . 
     The locking clip  116  has two opposing wings  152 . Each wing  152  has two spaced apart arms  154  that feature transversely orientated pin-like terminations (pins)  156 . A flexibly resilient serpentine tab  158  is disposed between the two arms  154 . More particularly, the wings  152  of the locking clip  116  slide into the apertures  150  of the holder  114  such that the serpentine tab  158  overlies a correspondingly curved tab  160  (seen best in  FIG. 6 ) disposed on the pad  140 . In particular, the arms  154  slide into grooves  155  located at the side peripheries of the holder apertures  150  such that each pin  156  extends out of corresponding groove  155  (seen best in  FIG. 10 ). The pins  156  ( FIG. 6 ) install into the serpentine grooves  146  of the pads  140 , preventing the pads  140  from lifting out yet enabling the pads  140  to rock or pivot about the pins  152 . In addition, the clip serpentine tabs  158  provide resistance to the pads pivoting in a direction away from the channel  134 . 
     For locking the clip  116  into the holder, the clip  116  includes apertures  162  disposed in each wing  152 . The resilient wings  152  must be forced over sloping locking tabs  164  (seen best in  FIG. 5 ) provided in the holder  114  until the locking tabs  164  sit in the apertures. Thereafter, the clip  116  will be releasably locked against the holder  114 . 
     In operation, the pads  140  are folded into the apertures  150  and the locking clip  116  is locked into the holder  114 . The liner  112  is initially only partially seated in the holder  114  such that the ratcheting mechanism is able to prevent the components from separating from one another. In this initial installation position, a mechanical detent is provided by the flexibly resilient locking clip tabs  158  and the corresponding holder tabs  160 , which tend to push the pads  140  inwardly into channel  134 , thus limiting the travel of the liner  112  into the holder  114  until a specified force is applied. This force is achieved when the weight of the glass panel is brought to bear against the liner  112 , which will occur only when the glass pane is fully seated in the liner  112 . Thus, the liner  112  will not move into the clamping portion of the assembly  100  until the glass panel is completely seated in the liner  112 , thereby ensuring the proper engagement between the glass panel and the liner  112 . When the window regulator (not shown in its entirety) is actuated to drive the glass pane into its closed position, the window regulator will drive the holder  114  against the held-in-position glass pane, thus fully seating the liner  112  and glass panel in the holder  114 . The ratcheting mechanism allows some deflection so that the liner teeth  128  and the holder pad teeth  144  can pass over each other, but only in a single direction, in the opposite direction the teeth are designed to lock, and deeper into the holder  114 , thus increasing the clamping force of the assembly  100 . Any subsequent slack between the liner and the glass panel that may later occur due to settling of the components or wear and tear will be taken up in due course as the window regulator is routinely operated and the liner  1   12  is forced deeper into the holder  114 . 
     It will be appreciated that although the above described embodiments have described the liner as having a U-shaped form and the holder as having a V shaped form for increasing the clamping forces on the glass panel as the liner is embedded deeper into the holder, the liner can instead be provided with sloping outer walls and the holder having a U-shaped form to achieve the same result. Similarly, other alterations and modifications may be effected to the above-described embodiments, which are intended to be examples of the invention only, without departing from the spirit of the invention.