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:
Mar. 26, 1991
Filed:
Mar. 26, 1990
Charles F Reed, Fairport, NY (US);
Valery Parker, Pittsford, NY (US);
Dover Industries, Inc., Chicago, IL (US);
Abstract
In an automatic screw machine two spindles are mounted coaxially one within the other and are keyed together for rotation in unison in the indexing head of the machine. The inner spindle has a collet on one end thereof; the outer spindle is shiftable axially relative to the inner spindle between collet opening and closing positions. A spring, which surrounds the inner spindle at one end thereof, urges a washer on the inner spindle against one end of the outer spindle normally to urge the outer spindle resiliently into a collet closing position. A hydraulic cylinder, which surrounds the outer spindle at the side of washer remote from the spring, contains a piston which is engaged at one side with the washer and at its opposite side communicates with a fluid pressure chamber. To open the collet pressure is applied to the fluid in the chamber, thereby causing the piston to compress the spring and to permit the outer spindle to move to a collet opening position.