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:
Nov. 13, 2001
Filed:
Jun. 18, 1999
Applicant:
Inventors:
Ronald A. Schilling, New Berlin, WI (US);
Harry C. Evans, Oconomowoc, WI (US);
Assignee:
ASI Technologies, Inc., Milwaukee, WI (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F16D 3/102 ;
U.S. Cl.
CPC ...
F16D 3/102 ;
Abstract
A hydraulic door opener provides a simplified mechanism for two-speed operation and for controlling the release of a brake that normally holds the door against movement. The mechanism includes a bypass valve between a fluid reservoir feeding the pump and the close control line running between the pump and the hydraulic motor. Fluid flow is directed from the close control line so that the door can be closed at slower rate than it is opened using a single speed motor. A brake control valve releases the brake when the control lines are pressurized.