Patent ID: 7213302

Claim:
A door retention device for retaining a door at least in a fully opened position and a slightly opened position, the device being used in a process of manufacturing an automobile including a first hinge arm secured to one of a body and the door, a second hinge arm secured to the other of the body and the door, and a hinge pin which interconnects the first and second hinge arms for turning movement relative to each other, wherein the door retention device comprises a torsion spring which is mounted to the first hinge arm and which includes a stationary arm portion, a movable arm portion and a torsion shaft for exhibiting a torsional repulsion force in accordance with the swinging of the movable arm portion, and a cam formed on the second hinge arm, the cam being provided with a first positioning recess and a second positioning recess in which the movable arm portion is brought into engagement in the fully opened position and the slightly opened position, and a projection disposed between the first and second positioning recesses and adapted to apply a load to the movable arm portion in accordance with the turning of the door, the torsion spring being mounted and demounted in a non-loaded state to and from the first hinge arm in the fully opened position of the door, wherein the first hinge arm comprises a pair of ribs which are distanced from each other and a cutout groove which is formed to pass through said pair of ribs, wherein the stationary arm portion is engaged with said cutout groove while extending through one of said pair of ribs, and wherein, when a tip end portion of the stationary arm portion is moved to a position near the other of said pair of ribs, the movable arm portion is released from its engagement with said cam.