COMBINATION HYDRAULIC AND PNEUMATIC DOOR CLOSER

摘要

A door closer capable of adjusting door closing speed, includes a pneumatic cylinder on the door frame, a hydraulic cylinder on the door, and a lever. One end of the lever is movably connected to the pneumatic cylinder, and the other end is connected to the hydraulic cylinder. The pneumatic cylinder includes a sliding rail, and a sliding member cooperated with the sliding rail. A hermetic chamber is formed by the sliding member and the sliding rail. An adjusting valve, for adjusting the air exhaust of the hermetic chamber, is provided on a wall of the hermetic chamber.

主权项

1. A closer for a screen door pivotally mounted in a door frame for movement between open and closed positions, the closer comprising:
a hydraulic cylinder; a pneumatic cylinder; one of the cylinders being mounted to the door frame and the other of the cylinders being mounted to the screen door; an arm connected to both cylinders such that the cylinders work together in closing the screen door.