초록 ▼

An hydraulic door closer has a motor/pump component to assist opening the door by supplying oil under pressure to the closer cylinder. The component is activated by a switch sensitive to the turning of the closer pinion shaft as the door is moved out of its frame. Further, the distance which the doo

An hydraulic door closer has a motor/pump component to assist opening the door by supplying oil under pressure to the closer cylinder. The component is activated by a switch sensitive to the turning of the closer pinion shaft as the door is moved out of its frame. Further, the distance which the door must move until the switch activates the motor/pump component is adjustable. The hydraulic circuitry is conveniently embodied in a single manifold block.

대표청구항 ▼

An hydraulic power-assist door closer comprising (a) a cylinder having a pinion mounted therein with an external drive shaft operatively connected to the door, (b) a piston operatively disposed in the cylinder and formed with a rack engaging the piston, (c) a manifold block secured against the cylin

An hydraulic power-assist door closer comprising (a) a cylinder having a pinion mounted therein with an external drive shaft operatively connected to the door, (b) a piston operatively disposed in the cylinder and formed with a rack engaging the piston, (c) a manifold block secured against the cylinder and having a boss sealingly disposed in an end of the cylinder, (d) check valve means in the piston adapted to close as the piston moves toward the said end and open when the door is opened manually, (e) spring means in the cylinder urging the piston in the direction of the block, (f) a pump mounted against the opposite side of the block from the cylinder and having an inlet port and a pressure outlet port disposed flat against the manifold, (g) means to drive the pump, (h) door-opening pressure passage means in the manifold conducting oil from the pressure outlet port through the boss and into the said end of the cylinder, (i) a plunger chamber in the manifold adjacent the boss, (j) door-opening return passage means in the cylinder and manifold conducting oil from the cylinder at a point on the opposite side of the piston from the boss, through the boss and into the plunger chamber adjacent the boss and out the chamber adjacent the boss and into the inlet port of the pump.