Patent Publication Number: US-2011067311-A1

Title: Window Regulator Lifter Plate With Integrated Lubrication System

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a window regulator assembly and, more particularly, to a lifter plate that includes an integrated lubrication system. 
     2. Description of Related Art 
     Automotive vehicles commonly include vehicle doors having a plastic carrier panel that is sandwiched between an exterior door panel and an interior door panel. The carrier panel is provided to support various components that are housed within the vehicle door such as a radio speaker and a window regulator assembly. The window regulator assembly includes a rail that is typically molded as part of the carrier panel and a lifter plate that is slidably coupled to the rail. The lifter plate supports a window pane and the rail guides the lifter plate in a vertical direction for movement of the window pane between a lowered or open position and a raised or closed position. The lifter plate is moved up and down along the rail by a cable or cables that are guided by pulleys disposed at opposite ends of the rail. The cable is driven by a reversible motor. 
     Typically, grease is used to lubricate the interface between the lifter plate and rail to ensure smooth and easy operation of the window pane between the open and closed positions. The grease is applied to the rail during assembly of the vehicle door, but as the lifter plate moves along the rail, it acts as a plow, and moves the grease aside. Repeated cycling of the window pane between the open and closed positions continues to remove the grease. Over time, with less grease on the rail, the movement of the window pane may become jerky or result in an audible scraping noise from within the vehicle door as the lifter plate moves along the rail. Less grease on the rail also results in a greater force being required to move the window pane, which puts a strain on the motor, cables and pulleys leading to early failure. 
     It is therefore desirable to provide a lifter plate having an integrated lubrication system to continuously lubricate a rail as the lifter plate travels up and down along the rail to move a window pane between an open position and a closed position. 
     SUMMARY OF THE INVENTION 
     According to one embodiment of the invention, a window regulator assembly for moving a window pane between an open position and a closed position includes at least one elongated rail and a lifter plate slidably coupled with the at least one elongated rail. The lifter plate is adapted to be coupled with the window pane. The at least one elongated rail guides the lifter plate to move the window pane between the open and closed positions. A lubrication system lubricates the at least one elongated rail as the lifter plate moves the window pane between the open and closed positions. The lubrication system includes a reservoir contained within the lifter plate, a lubricant storing and releasing material disposed in the reservoir, and an applicator extending from within the reservoir to lubricate the at least one elongated rail. 
    
    
     
       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 upper perspective view of a plastic carrier panel for a vehicle door; 
         FIG. 2  is a front perspective view of a lifter plate for a window regulator assembly according to one embodiment of the invention; 
         FIG. 3  is a front view of the lifter plate; 
         FIG. 4  is an enlarged view of detail  4  in  FIG. 3 ; 
         FIG. 5  is a fragmentary, cross-sectional view of the lifter plate and plastic carrier panel illustrating a lubrication system; and 
         FIG. 6  is a rear perspective view of the lifter plate. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Referring to the Figures, a plastic carrier panel  10  for a vehicle door is shown. The carrier panel  10  includes a window regulator assembly  12  that is used for moving a window pane (not shown) between a lowered or open position and a raised or closed position, as is well known in the art. The window regulator assembly  12  includes at least one elongated rail  14  and at least one lifter plate  16  slidably coupled to the rail  14 . In the embodiment shown, the rail  14  is integrally molded with the carrier panel  10  and extends in a generally vertical direction. The rail  14  has a generally L-shaped cross-section, as shown in  FIG. 5 . The lifter plate  16  is adapted to support the window pane and the rail  14  guides the lifter plate  16  for sliding movement along the rail  14  in the vertical direction for movement of the window pane between the open and closed positions. It is contemplated that the lifter plate  16  is moved along the rail  14  in the vertical direction by a reversible motor (not shown) that drives a cable or cables (not shown), which are guided by pulleys (not shown) disposed at opposite ends of the rail  14 . It is appreciated, however, that the lifter plate  16  may be moved along the rail  14  by any suitable means without varying from the scope of the invention. 
     The lifter plate  16  is configured to include a front side  18 , a rear side  20 , a lower end  22  and an upper end  24 . The front side  18  of the lifter plate  16  includes a cable attachment portion  26  for coupling the lifter plate  16  to the cable or cables. The front side  18  also includes a pair of clips  28  that are spaced apart in the vertical direction. The clips  28  are suitably formed to engage the L-shaped cross-section of the rail  14 , thereby slidably coupling the lifter plate  16  to the rail  14 . When the lifter plate  16  is assembled with the carrier panel  10  the front side  18  of the lifter plate  16  is disposed directly adjacent to the carrier panel  10 . The rear side  20  of the lifter plate  16  includes a plurality of stiffening ribs  30  that provide structural rigidity to the lifter plate  16 . The rear side  20  also includes a mount  32  for receiving a lower edge of the window pane. A screw, bolt or other attachment means extends through an aperture  34  in the lifter plate  16  to secure the window pane to the lifter plate  16 . 
     The lifter plate  16  also includes an integrated lubrication system, generally shown at  36  in  FIG. 5 . The lubrication system  36  lubricates the rail  14  and therefore the interface between the clips  28  and the rail  14  as the lifter plate  16  moves along the rail  14  in the vertical direction to provide smooth and easy movement of the window pane between the open and closed positions. The lubrication system  36  includes an enclosed reservoir  38  that is housed within the lifter plate  16  near the upper end  24  thereof. A back wall  40  of the reservoir  38  on the rear side  20  of the lifter plate  16  is shown in  FIGS. 1 and 5 . The reservoir  38  may be filled with a lubricant storing and releasing material  42 , such as an oil impregnated, fibrous wicking material as is disclosed in commonly owned U.S. Pat. Nos. 3,466,244; 3,214,375; and 2,966,459, which are hereby incorporated by reference. An example of this material  42  is sold under the trademark PERMAWICK®, which is produced by Permawick Company of Birmingham, Mich. Alternatively, the reservoir  38  may be filled with a blend of formulated oil and thickening additives  42 . An example of this material  42  is sold under the trademark PERMAGEL®, which is also produced by Permawick Company of Birmingham, Mich. Both of these materials  42  provide a predetermined oil release factor which controls or regulates the rate at which lubricant is released. The reservoir  38  is filled with one of the materials  42  through an aperture  44  in the front side  18  of the lifter plate  16  or through a re-sealable opening (not shown) in the back wall  40  of the reservoir  38 . Rather than filling the reservoir  38  with one of the above-described materials, it is appreciated that any suitable lubricant may be used without varying from the scope of the invention. 
     The lubrication system  36  also includes a felt applicator  46  that automatically and continuously transfers lubricant from the reservoir  38  to the rail  14  as the lifter plate  16  moves along the rail  14  in the vertical direction. The applicator  46  extends through the aperture  44  in the front side  18  of the lifter plate  16  into the reservoir  38 . The aperture  44  is positioned near the upper end  24  of the lifter plate  16  generally in-line with the clips  28 . The applicator  46  is sized to fill-up the entire aperture  44 . In other words, the peripheral edges of the applicator  46  directly contact the peripheral edges of the aperture  44 . A first end  48  of the applicator  46  is in contact with an inner surface of the back wall  40  of the reservoir  38  to provide support to the applicator  46 . A second end  50  of the applicator  46  protrudes from the front side  18  of the lifter plate  16 . The second end  50  of the applicator  44  includes a slot  52  that is generally L-shaped and complementary to the L-shaped cross-section of the rail  14 . The complementary shape of the slot  52  encompasses the rail  14  such that the applicator  46  contacts and lubricates every surface of the rail  14  as the lifter plate  16  moves along the rail  14  in the vertical direction. It is appreciated that the applicator  46  may be any suitable material without varying from the scope of the invention. 
     A pair of tabs  54  provides support to the second end  50  of the applicator  46  protruding from the front side  18  of the lifter plate  16  to maintain contact between the applicator  46  and the rail  14 . The tabs  54  are spaced apart in a lateral direction and are disposed on opposite sides of the aperture  44 . The space between the tabs  54  provides clearance for the rail  14 . In the embodiment shown, viewed from the front side  18  of the lifter plate  16 , the tabs  54  have opposing C-shapes such that each one of the tabs  54  engages the applicator  46  on three sides. The second end  50  of the applicator  46  extends farther from the front side  18  of the lifter plate  16  than the tabs  54 . It is appreciated that the specific design of the tabs  54  may change depending upon the design of the applicator  46  and the cross-sectional shape of the rail  14  without varying from the scope of the invention. 
     The invention has been described in an illustrative manner, and it is to be understood that the terminology, which has been used, is intended to be in the nature of words of description rather than of limitation. 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 other than as specifically described.