DOOR OPERATING ASSEMBLY.

摘要

A door operating assembly for opening and closing vehicle doors at a constant door edge force includes a frame. A teeter lever assembly is pivotally mounted on the frame and is connected to a connecting rod assembly connecting the teeter lever assembly and the vehicle doors. A cylinder is mounted on the frame and includes a reciprocally mounted rod. The rod is reciprocated by pressurized air introduced into the cylinder. The rod is connected to the teeter lever assembly to rotate the teeter lever assembly. The teeter lever assembly includes a variable diameter cam. A spring for closing the doors is secured at a first end to the frame and at a second end to a flexible connection member. The flexible connection member connects the spring to the cam and wraps around the outer periphery of the cam upon door opening. The energy stored in the spring at full extension is used to close the doors. To maintain the force on the doors constant during opening and closing, the cam provides a larger moment arm in the door closed position than the door open position. To provide closing force for the door an accumulator may be provided. The accumulator includes a container in fluid communication with a vent in the cylinder. As the doors open, air in the cylinder is forced out the vent and into the container. During door closing, air accumulated in the container reenters the cylinder to extend the rod and close the door. An adjustable relief valve may be included with the container to maintain pressure in the container below the source pressure for the cylinder.