Abstract:
A control assembly for releasing a latch has a base plate ( 26 ) for mounting components of the control assembly. A pivotally mounted ( 28 ) input lever is movable between a ready position and a release position. The input lever ( 28 ) connects to a release handle ( 22 ). A pivotally mounted output lever ( 30 ) connects to a latch ( 14, 16 ) and transmits a releasing force. A pivotally mounted locking lever ( 34 ) is rotatable between a locked position and an unlocked position. A link ( 98 ) slidably engages the output lever ( 30 ) and pivotally engages the locking lever ( 34 ). When the locking lever ( 34 ) moves between the locked and unlocked positions, the link ( 98 ) responsively decouples and couples the input lever ( 28 ) and the output lever ( 30 ) to allow independent and dependent rotation thereof, respectively, selectively transferring the releasing force from the release handle ( 22 ) to the latch ( 14, 16 ).

Description:
FIELD OF INVENTION 
     This invention relates to closure members for vehicles which close a compartment such as a tailgate, a cargo door, or a sliding door or the like. The door is typically moved, for example pivoted or slid from a closed position to an open position. In order to effect this movement, a handle must be operated through a control assembly to release the latch mechanisms allowing the closure to be moved to the open position. This present invention finds particular application therefore in providing such a control assembly which has simplified the structures heretofore known reducing the number of parts thereof and increasing the reliability thereof while reducing the overall power consumption required in a preferably power actuated control assembly. 
     BACKGROUND OF INVENTION 
     Within the prior art there exists a number of structures for releasing a closure such as a tailgate. For example, U.S. Pat. No. 5,531,498, as one example, refers to a power lift-type tailgate and includes a control assembly which is cable driven once the latches are released. The drive includes a motor driving a cable reel to lift the tailgate assembly. 
     Other designs are also known, which designs have been installed on the lift gates of certain production vehicles. These designs include an actuator which converts linear motion to a rotary motion for the locking lever, and then through the two-position floating pin to a further linear motion of the floating pin to a rotary motion for the output lever to a further linear motion for the cable release. A significant amount of friction therefore is developed, and hence friction loss is experienced as a result of utilizing such a system. Incorporated with the locking lever is a two-position over center toggle spring which allows the two positions attained by the floating pin. The locking lever has an emergency manual override tab which may be accessed should the actuator fail. Therefore, when the input lever is operated by a handle connected to the control via a rod or a cable, the input arm of the input lever will engage the floating pin and therefore allow release of the latches. Should the floating pin however be moved via the operation of the locking lever to the inoperative position, then the input arm of the input lever will not be able to access the floating pin, and hence the output lever will not operate in spite of the fact that the input lever will operate. Such a control assembly therefore includes a first pivot connected to the locking lever, a second pivot connected with the floating pin, a third pivot about which the locking lever pivots, and a fourth pivot about which the input lever and the output lever pivot. Within the actuator itself, it is estimated that the electrical requirements would be approximately 10 watts normally, and peak at approximately 50 watts or more, with up to 5 amps being drawn by the motor. 
     Clearly therefore, the problems can be seen in providing such a device in that a significant amount of the power utilized by the actuator goes into friction losses when transferring the power from the actuator to the actual cables. Secondly, the reliability of the product must be questioned in that many of the parts, for example such as the tab from the locking lever which accesses the opening of the linear actuator plunger, undergoes a dynamic load over each cycle and may tend to fail in time. Secondly, the pivot for the locking lever may tend to bind in time, or the floating pin may also bind within the slot between its two positions. 
     SUMMARY OF THE INVENTION 
     The disadvantages of the prior art may be overcome by providing a latch control assembly having a simple mechanism for locking and unlocking a lift gate or door and for effecting unlatching thereof. 
     According to one aspect of the invention, there is provided a control assembly for releasing a latch. The control assembly has a base plate for mounting components of the control assembly. A pivotally mounted input lever is movable between a ready position and a release position. The input lever connects to a release handle. A pivotally mounted output lever connects to a latch and transmits a releasing force. A pivotally mounted locking lever is rotatable between a locked position and an unlocked position. A link slidably engages the output lever and pivotally engages the locking lever. When the locking lever moves between the locked and unlocked positions, the link responsively decouples and couples the input lever and the output lever to allow independent and dependent rotation thereof, respectively, selectively transferring the releasing force from the release handle to the latch. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     In drawings which illustrate an embodiment of the invention, 
     FIG. 1 is a perspective view of lift gate incorporating the control assembly of the present invention; 
     FIG. 2 is an exploded view of the control assembly of the present invention; and 
     FIG. 3 is a perspective view of the control assembly of FIG.  2 ; 
    
    
     DESCRIPTION OF THE INVENTION 
     Referring now to FIG. 1, there is illustrated a tailgate assembly or door assembly  12 , normally pivotally mounted, which allows the door  12  to swing upwardly in the conventional motion of a tailgate. Two latches,  14  and  16  are conveniently located proximate the sides of the tailgate  12  which will engage keepers or strikers when the tailgate  12  is closed. The latches  14 ,  16  are oriented in such a way that the fish mouths will each engage with the respective strikers as is well known in the art. The latches  14 ,  16  are conventional and include pawl release levers to which are connected the Bowden cables  18 ,  20  for each latch. The Bowden cables  18 ,  20  are conveniently run through clips in openings in the body panels which allow motion of the cable and yet securement of the cable in relation to the panel. The Bowden cables  18 ,  20  operatively connect to the control assembly  10  of the present invention. Release handle  22  is operatively connected via a cable or rod  24  to the input lever of control assembly  10 . Release handle  22  is pivotally mounted to the tailgate  12  in a manner conventional in the art. Actuation of the release handle  22  effects the release of the latches  14 ,  18  when the control assembly  10  is in the operative or unlocked position which will be described hereinafter. 
     Referring now to FIG. 2, there is illustrated the control assembly  10  which includes a mounting or base plate  26 , an input lever  28 , an output lever  30 , a locking block  32 , a locking lever  34  and an actuator  36 . 
     Base plate  26  is preferably a stamped metal formed with various features including mounting holes, Bowden cable attachment tabs  38 ,  40 , an arcuate guide slot  42 , and a control window  44 . Tabs  38 ,  40  extend generally perpendicular from base plate  26 . Tabs  38  and  40  have cutouts for receiving the outer cable shell or sheath of Bowden cables  18 ,  20 . Base plate  26  has an embossed area  46  having a bore  48  and an embossed area  50  having a bore  52 . Base plate  26  is otherwise configured for mounting the components of the control assembly  10  onto the base plate  26  and for matching the footprint for mounting the control assembly  10  onto the frame of the lift gate  12 . 
     Input lever  28  is preferably a stamped metal and formed to be pivotally mounted onto base plate  26 . Input lever  28  has two arms  54 ,  56  extending from opposite sides of pivot  58 . Ann  54  has tabs  60 ,  62  extending in opposite directions. Tab  62  extends towards the base plate  26  and extends through control window  44 . Control window  44  limits the pivotal travel of the input lever  28  between a ready position and a release position. Arm  56  has a tab  64  having an aperture for receiving spring  66 . Spring  66  extends between tab  40  and tab  64  to bias the input lever  28  to the ready position. 
     Output lever  30  is preferably a stamped metal and formed to be pivotally mounted onto base plate  26  coaxially with input lever  28 . Output lever  30  is mounted on pivot pin  68  which pivotally mounts input lever  28  through bore  48  on base plate  26 . Output lever  30  has three arms  70 ,  72  and  74 . Arms  70 ,  72 ,  74  extend radially from a central pivot  76  through which pivot pin  68  extends. Arms  70 ,  72  are preferably diametrically opposed. The distal ends of arms  70 ,  72  each has a bore for receiving clips  78 ,  80  in a snap fit. Clips  78  and  80  are connected to the ends of cables  18 ,  20 , respectively. Pivotal movement of output lever  30  will simultaneously extend and retract each of cables  18 ,  20  for release of latches  14 ,  16 . Arm  72  has a tab  82  at the distal end, which tab extends through guide slot  42  on base plate  26 . Guide slot  42  limits pivotal travel of the output lever  30 . Arm  74  has a radially extending slot  84  and a cooperating axially extending flange  86 . Spring  87  extends between arm  74  and the base plate  26  to bias the output lever  30  to a position, wherein the cables  18 ,  20  will be at an unextended length or retracted position. 
     The locking lever  34  is preferably a stamped metal component and formed to be drivingly mounted on output shaft  88  of actuator  36 . Locking lever has two arms  90 ,  92  extending from a central core  94 . Core  94  has an aperture complementary to the shape of output shaft  88  for a driving engagement therewith. A screw  95  attaches the locking lever  34  to the output shaft  88 . Arm  90  has a tab  96  at the distal end. Arm  92  has a keyway aperture  97  for pivotally connecting with link  98  of locking block  32 . Connecting link  98  has, at one end, pin  100  having locking tabs  102  and locking block  32  at the opposite end. Locking block  32  is pivotally connected to and slightly spaced from the connecting link  98 . The locking tabs  102  can be inserted into keyway aperture  97  to pivotally connect the connecting link  98  to the locking lever  34 . The locking block  32  engages the output lever  30 . Specifically the mounting pin of the locking block  32  will be inserted through slot  84  of output lever  30 . Locking block  32  will slide against flange  86 . Rotation of locking lever  34  will cause the locking block  32  to slide in the slot  84  between an operative or unlocked position wherein the locking block  32  will extend between the flange  86  and the tab  60  of input lever  28  and an inoperative or locked position wherein the locking block  32  does not engage tab  60  of input lever  28 . In the embodiment illustrated, the operative position is radially outward and the inoperative or locked position is radially inward along slot  84 . 
     Actuator  36  is conventional in design. In one embodiment of the invention, a motor drives output shaft  88  through a series of gears (not illustrated) to rotate locking lever  34  between a locked position and an unlocked position. 
     Referring now to FIG. 3, the locking block  32  moves linearly along the slot  84 . When the locking block  32  is in the operative or unlocked position, movement of the input lever  28  will translate to the output lever  30  through the locking block  32 , so that the input lever  28  is coupled to the output lever  30  to rotate dependently. However, when the locking block  32  travels radially inwardly to the disengaged or locked position, the operative connection between the input lever  28  and the output lever  30  is removed. Input lever  28  is uncoupled from the output lever  30  to rotate independently. Should the handle  22  be utilized and the input lever  28  rotated, the input lever  28  will merely freely move on its pivot without moving any of the other components of the control assembly  10 . Further, the locking lever  34  has an emergency manual override tab  96  which may be accessed should the actuator  36  fail, or alternatively in another embodiment, when the actuator is not present, be in communication with a manually operable user accessible device such as a knob or the like or alternatively in communication with a child proofing lever. 
     In operation therefore, the actuator  26  or user accessible operator would be operated or powered via a push button, knob, a remote or the like causing the rotation of the locking lever  34  about its pivot, and therefore cause the linear motion of the locking block  32  relative to arm  74  of the output lever  30 , moving the locking block  32  in and out of operative interconnection between the input lever  28  and the output lever  30  to couple and uncouple the input lever  28  and the output lever  30 . Therefore, when the locking block  32  is in the operative or unlocked position, the actuating tab  60  of the input lever  28  will engage the locking block  32  adjacent thereto which in turn will transmit any force transmitted through the input lever  28  to the flange  86  of the output lever  30  causing the output lever  30  to rotate upon its pivot to allow for the release of the latches  14 ,  16  as the cables  18 ,  20  are retracted responsive to the output lever  30  rotation. However, when the locking block  32  is translated to the disengaged or locked position, whereat the tab  60  can no longer engage the locking block  32 , regardless of movement of the handle  22  and input lever  28 , the latches  14 ,  16  cannot release. 
     The invention has been described in an illustrative manner with respect to the preferred embodiments thereof, and it is understood and implied that the terminology that has been used is intended to be for descriptive purposes only and not for the interpretation in limiting the invention. As many changes can be made to the preferred embodiments of the invention without departing from the scope thereof; it is intended that all matter contained herein be considered illustrative of the invention and not in a limiting sense.