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:
Feb. 28, 1989
Filed:
Oct. 14, 1986
Applicant:
Inventors:
Merrill E Berchtold, Loveland, OH (US);
John R Witzel, Goshen, OH (US);
Assignee:
Cincinnati Milacron Inc., Cincinnati, OH (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
F15B / ;
U.S. Cl.
CPC ...
91421 ; 91361 ; 91364 ;
Abstract
A spindle carrier, which is movable vertically by an electric servo motor through a relatively long ball screw, has a substantially constant counterbalance force maintained on it irrespective of whether it is moving up or down. This prevents compression or tension of the ball screw. The counterbalance force is maintained substantially constant through sensing the load on the spindle carrier and using the sensed load to vary the hydraulic pressure applied to a piston within a hydraulic cylinder and connected through a chain to the spindle carrier to apply the counterbalance force.