Patent ID: 8136207

Claim:
A swinging door assembly, comprising: a panel; a frame having a horizontal portion, the horizontal portion having an aperture therethrough; an elongated pivot pin vertically disposed through the aperture, the pivot pin being coupled to the panel such that the pivot pin and the panel rotate about a longitudinal axis of the pivot pin relative to the horizontal portion of the frame; a gripper feature located on a surface of the pivot pin, the gripper feature engages a corresponding surface on the panel such that when the panel is rotated, a resulting torsional force transferred to the pivot pin is spread over a contact area between the gripper feature and the surface on the panel; a torsional spring having two spring arms, the torsional spring being coaxially disposed around the pivot pin, wherein the torsional spring biases the panel into a position that is parallel to a longitudinal axis of the horizontal portion of the frame; and a bent arm fixed to the pivot pin, the bent arm being positioned between the spring arms such that when the panel and the pivot pin and the bent arm coupled thereto are pivoted about the longitudinal axis of the pivot pin, one arm of the torsional spring acts upon the bent arm to oppose the rotation.