The present invention relates generally to door hinges for a motor vehicle, and more particularly to a double pivot door hinge for permitting a greater than ninety degree opening of a vehicle door.
U.S. Pat. No. 4,719,665 discloses a double pivot hinge for vehicle doors. A first and second latch means are alternately movable between latched and unlatched positions to either latch the hinge arm to one hinge butt mounted to the door to permit a 90-degree movement, or to latch the hinge arm to another hinge butt mounted to the vehicle for 90 to 180 degree movement.
U.S. Pat. Nos. 5,561,887 and 5,685,046 disclose vehicle double pivot door hinges. The door rotates about the vehicle-mounted pivot for a zero to 90 degree movement, the vehicle-mounted pivot being locked releasably in the 90 degree position, for example by a ball detent. Ball detents or cams exterior to the door-mounted pivot keep the door-mounted pivot from moving during the zero to 90-degree action. These ball detents or cams then release to permit the door-mounted pivot to rotate, so that a 90-degree to 180-degree motion can be achieved.
The actual pivots of these double-pivot prior art devices all have the same or no resistance, so that external latches or devices are required to provide the desired movements and braking.
U.S. Pat. No. 5,918,347, assigned to Edscha and hereby incorporated by reference herein, shows a door hinge with a resistance pivot where a locking member acts directly on a cylinder stem having grooves. The resistance pivot can provide for door opening angles up to 270 degrees. However, only a single pivot is provided.
An object of the present invention is to provide a double-pivot door hinge that permits more than a ninety-degree rotation of the door of the vehicle having a simplified and/or reliable construction. Another alternate or additional object is to permit a double-pivot door hinge door hinge to provide various locking positions at various angles over a range of door movement.
By having the braking resistances directly at the pivots be different a simplified and more reliable construction can result. In the prior art devices, the pivots themselves had similar or no resistances, and the braking resistances were provided exteriorly to the pivots.
Moreover, as a result of the braking resistance of the pillar-side pivot being less that the braking resistance of the door-side pivot, upon opening of the door to a certain intermediate position, for example 90 degrees, the door pivots about the pillar-side pivot while door-side pivot remains fixed.
Preferably, a stop is provided to prevent the pillar-side pivot from rotating past the intermediate position. At this point further pulling of the door with a force greater than the braking resistance of the door-side pivot results in the door-side pivot rotating so that the door can be moved from the intermediate point to a fully open position, for example 180 degrees.
During closing, the braking resistance of the door-side pivot then may be less than the braking resistance of the pillar-side pivot, so that the door-side pivot first rotates to close the door from the fully-opened position to the intermediate position.
Another stop can be provided to prevent the door-side pivot from rotating past the intermediate position as the door is being closed.
The double pivot hinge according to the present invention makes it possible, during opening and closing of the door, to provide for predetermined movement of the door using resistance pivots. Use of further connections exterior to the pivots to provide resistance can be avoided.
The link is preferably a U-shaped link.
Preferably, the door and pillar side pivots include a locking member, such as a needle roller, biased against a hinge pin pivotally received in a gudgeon of the respective door or pillar connector. The pivots are also received in gudgeons of the link.
The pivot resistance mechanism involves a use of a sleeve-shaped cam which has pre-determined notches cut into it to provide door open positions. Preferably, on the cam rides a needle roller, which is forced against the cam by a spring. As the roller rides on the cam during pivotal movement, door braking positions are created as the roller enters into the notches on the cam profile. The braking resistance is achieved when the roller rolls out of the notch. The braking resistance can be modified by the sizes of the notches, and by the sizing of the rollers.
Preferably, each pivot has a cam with two notches. Three locking positions upon the pivotal movement of the link about the two pivots are thus established: one the fully-closed position of the door (zero degrees), a second at an intermediate position, for example 90xc2x0 and a third at a fully open position, for example at 180xc2x0. When the door is closed at 0xc2x0, the pillar-side and the door-side pivot rollers are both in the respective first notches in the cam. When the door is opened to the intermediate position the pillar-side pivot travels so that the roller of the locking mechanism engages a second notch on the pillar-side cam. The door-side pivot remains with its locking mechanism roller in the first notch, due to the larger resistance on the door side pivot.
When the door is opened further from the intermediate position to the fully open position, the door-side pivot travels so that its locking mechanism roller engages the second notch of the door-side cam.
Preferably, a positive stop is also provided, so that the full open door, which may have a tendency to crash to the body in extreme torque applications, avoids travel past the fully open position, or a position slightly past the fully open position.
The different braking resistances can be achieved by different pre-loading of the compression springs, different profiling of the locking member (roller) or of the surface of the respective cam of the hinge pin.
The size and weight of the door often dictates that only one hinge cannot hold the door in position both for rotational and twist rigidity.
A second hinge assembly thus may be provided. The door with two hinge assemblies can provide heavier doors proper support during rotation, the hinge assemblies being positioned with the hinge gudgeons coaxial with each other.
The second hinge assembly may be similar to the resistance hinge according to the present invention, as having two resistance hinges can provide better control and more stiffness and rigidity. However, control of the movement of both the resistance hinge assemblies simultaneously with repetitive results may be difficult from a manufacturing standpoint. To avoid this, the present invention preferably provides the notch-braking mechanism for the one of the hinge assemblies while the other hinge assembly is lock- or resistance-free. The resistance-free hinge has a similar construction to the resistance hinge, with the door and body connectors connected using a U-shaped link at the two gudgeons. The bending stiffness is provided by connecting the resistance hinge and the resistance-free hinge using a rod or connecting element which transmits the controlled movement of the door and the pillar-side pivot of the resistance hinge to the resistance-free hinge assembly.
The two pivot axes of the pillar-side and the door-side pivots preferably are slightly off parallel to each other so as to provide for a door assist. This arrangement of the pivot axes makes it possible, upon pivoting of the door, to have a variable door assist as the door is cycled. Particularly, when the door is being opened from the intermediate to the fully open position, the door assist helps the door to move to the final fully-open position. While in closing mode from the intermediate to the closed position, the door assist aids the door in latching.
Preferably, the planar base of the pillar connector is attached to the outer surface of the pillar, and the planar base of the door connector is attached to the side of the door so that the two base plates are arranged in mutually perpendicular planes.
A particular favorable feature of the invention includes that the double pivot hinge is so secured that it is not visible from the outside, insuring an aesthetic appearance of the vehicle. The hinge remains hidden from an outsider when the door is closed. The sheet panels of the door and the body may be closely aligned with each other with a small gap.