Patent Application
20090184533
The present invention relates generally to vehicle endgates and, in particular, to hinge assemblies for such vehicle endgates.
Vehicle endgates, and in particular, liftgates on pickup trucks typically do not include a mechanism for damping movement or lift assist for tailgate closing. More recently, though, some pickup trucks include lift assist to not only reduce the effort needed by one closing the tailgate, but to also add a perceived feeling of quality when opening and closing the tailgate.
A concern arises with particular lift assist mechanisms in that the additional mechanisms do not package within the rear vehicle structure without interfering with the vehicle structure or other vehicle subassemblies. Such re-design of vehicle structure or components may be more cost prohibitive than the addition of a lift assist is worth. Thus, it is desirable to provide a vehicle endgate lift assist that not only provides lift assist and damping, but also minimizes the packaging space needed for such an assembly.
An embodiment contemplates a vehicle endgate hinge assembly pivotally coupling an endgate to an endgate opening shut-face on a vehicle about an endgate pivot axis. The hinge assembly may comprise a bodyside hinge strap, a crank, a nut and an energy storage mechanism. The bodyside hinge strap may include a hinge support boss extending through the endgate opening shut-face and having a central hole that is coaxial with the endgate pivot axis, a mounting plate located outboard of the endgate opening shut-face, and a threaded portion extending from the mounting plate through the endgate opening shut-face. The crank may include a hinge key configured to be pivotally coupled to a member mounted on the endgate, a pivot shaft extending from the hinge key through the central hole coaxial with the endgate pivot axis, a lever arm extending from the pivot shaft approximately normal to the endgate pivot axis, and a ball extending from the lever arm spaced from the endgate pivot axis. The nut may be located inboard of the endgate opening shut-face and threadably received on the threaded portion, and the energy storage mechanism may be coupled to the ball and configured to store and release energy based on pivoting of the lever arm.
An embodiment contemplates a vehicle endgate hinge assembly pivotally coupling an endgate to an endgate opening shut-face on a vehicle about an endgate pivot axis. The hinge assembly may comprise a bodyside hinge strap including a hinge support boss extending through the endgate opening shut-face and having a central hole that is coaxial with the endgate pivot axis, a mounting plate located outboard of the endgate opening shut-face, a first fastener, spaced from hinge support boss, extending through the mounting plate and the endgate opening shut-face, and a second fastener, spaced from the first fastener and the hinge support boss, extending through the mounting plate and the endgate opening shut-face; a crank including a hinge key pivotally coupled to a member mounted on the endgate, a pivot shaft extending from the hinge key through the central hole coaxial with the endgate pivot axis, a lever arm extending from the pivot shaft approximately normal to the endgate pivot axis, and a ball extending from the lever arm spaced from the endgate pivot axis; a first nut located inboard of the endgate opening shut-face is received on the first fastener, and a second nut located inboard of the endgate opening shut-face is received on the second fastener; and an energy storage mechanism is coupled to the ball and stores and releases energy based on pivoting of the lever arm.
An embodiment contemplates a vehicle endgate hinge assembly pivotally coupling an endgate to an endgate opening shut-face on a vehicle about an endgate pivot axis. The hinge assembly may comprise a bodyside hinge strap including a hinge support boss extending through the endgate opening shut-face, having a central hole that is coaxial with the endgate pivot axis and a threaded portion on an outer surface, and a mounting plate located outboard of the endgate opening shut-face; a crank including a hinge key pivotally coupled to a member mounted on the endgate, a pivot shaft extending from the hinge key through the central hole coaxial with the endgate pivot axis, a lever arm extending from the pivot shaft approximately normal to the endgate pivot axis, and a ball extending from the lever arm spaced from the endgate pivot axis; a nut is located inboard of the endgate opening shut-face and threadably received on the threaded portion; and an energy storage mechanism is coupled to the ball and configured to store and release energy based on pivoting of the lever arm.
An advantage of an embodiment is that the hinge assembly has a minimal inboard-outboard width, thus minimizing the potential to interfere with other vehicle components, such as a lighting parabola of a tail lamp housing, while still providing for lift assist of the endgate.
Referring to
Referring now to
The hinge assembly 28 also includes a bodyside hinge strap 48 that is mounted to the endgate opening shut-face 32 on its outboard side. Optionally, a support plate 50 may be mounted between the shut-face 32 and the hinge strap 48, and a hinge strap reinforcement 52 may be mounted on the inboard side of the shut-face 32. When referring to inboard and outboard herein, being inboard means that the object/surface is closer to the center of the vehicle (in the direction of the pivot axis 38) than the relative position of an object/surface that is referred to as being outboard.
The body side hinge strap 48 has a mounting plate 53 mounted outboard of the shut-face 32 and a hinge support boss 54 extending from the mounting plate 53 inboard through a hole 55 in the shut-face 32 (and support plate 50 and hinge strap reinforcement 52, if included in the assembly). The support boss 54 is coaxial with the endgate pivot axis 38 and includes bushings 56 mounted therein that supports the pivot shaft 42 and allows it to rotate more smoothly relative to the support boss 54. The bodyside hinge strap 48 also includes a pair of mounting holes 58, extending through the mounting plate 53 and spaced from the support boss 54, that align with mounting holes 60 through the shut-face 32 (and support plate 50 and hinge strap reinforcement 52, if included in the assembly). A pair of body attachment bolts 62, preferably with countersunk heads, extend inboard through the mounting holes 58, 60 and are secured with mounting nuts 64, located inboard of the shut-face 32. The body attachment bolts 62, then, not only mount the bodyside hinge strap 48 to the vehicle body 21, but also prevent it from rotating relative to the body.
A gas strut 68 includes a socket 70 at a first end that mounts to the ball 46 extending from the lever arm 44. A second, upper end of the gas strut 68 includes a strut-to-body attachment 72 that mounts to the vehicle body 21. The gas strut 68 and socket 70 can be mounted close to the lever arm 44, with the lever arm 44 located close to the bodyside hinge strap 48. This can occur because the body attachment bolts 62 extend inboard, with countersunk heads on the outboard side of the bodyside hinge strap 48 and the nuts on the inboard side of the shut-face 32. Thus, the hinge assembly 28 minimizes how far it must extend outboard relative to the endgate opening shut-face 32, minimizing potential packaging interference with certain vehicle components, such as, for example, a lens parabola (not shown) for a tail lamp housing (not shown).
The operation of the hinge assembly 28 will now be discussed. With the endgate 26 in a vertical, closed position (shown in
In this embodiment, though, the bodyside hinge strap 148 is modified. Only one hinge strap mounting hole 158 extends through the strap 148, thus reducing the size of the strap 148. One body attachment bolt 162 extends inboard through the mounting hole 158 and shut-face mounting hole 160 (and through a support plate 150 and hinge strap reinforcement 152, if so provided) and is secured with a mounting nut 164 located on the inboard side of the shut-face 132. This body attachment bolt 162, since it is offset from the endgate pivot axis 138, will prevent the bodyside hinge strap 148 from rotating. Also, the ball mounting location on the lever arm 144 no longer overlaps with the hinge strap 148, thus possibly allowing for an even more compact configuration than the first embodiment. To make sure that the bodyside hinge strap 148 is fully secured to the shut-face 132, the support boss 154 has threads 176 on its outer surface. The threaded support boss 154 extends inboard through the hinge hole 155 in the shut-face 132 and is secured with a support nut 178 located on the inboard side of the shut-face 132.
As the support nut 278 is secured into its fully assembled position, the hinge strap reinforcement is secured between the support nut 278 and the shut-face 232. The hinge strap reinforcement 252 preferably has a hole 280 therethrough that is configured to prevent rotation between the hinge strap reinforcement 252 and the bodyside hinge strap 248. The hinge strap reinforcement 252 also includes an anti-rotation tab 282 that extends through a mounting hole 260 in the shut-face 232. Accordingly, rotation of the bodyside hinge strap 248 is prevented.
Additionally, the hinge assembly 228 may include a washer shim 284 located between the lever arm 244 and the bodyside hinge strap 248. The particular thickness of washer shim 284 employed, if any, can be used to adjust the fit of the endgate in the endgate opening in order to account for manufacturing variations. Also, bushings (not shown in this embodiment) may be employed between the hinge support boss 254 and pivot shaft 242, if so desired.
While certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.
