The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 1979
Filed:
Nov. 30, 1977
Applicant:
Inventor:
Sideny Lieberman, Lancaster, PA (US);
Assignee:
Reading Door Closer Corp., Reamstown, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E05F / ;
U.S. Cl.
CPC ...
16 59 ; 16 84 ;
Abstract
Hydraulic door closer apparatus comprises a cylinder, a piston disposed in the cylinder, linkage means coupled to the piston for transmitting forces between the piston and a door, and a hydraulic circuit for controlling movement of the piston in the cylinder. A temprature responsive control element is provided in the hydraulic circuit to alter the characteristics of the circuit in response to changes in ambient temperature or temperature of the fluid within the closer.