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:
Jul. 12, 1983
Filed:
Mar. 02, 1981
James C Johnson, Charlotte, NC (US);
Duff-Norton Company, Charlotte, NC (US);
Abstract
A shielding bladder for the venting arrangement of a linear actuator having a housing, a reciprocable member disposed therein for linear reciprocable movement therethrough, and a venting arrangement in the housing for communicative flow of ambient air into and out of the housing during operation. The bladder is a sleeve sealably affixed exteriorly to the housing enclosing the venting arrangement and defining a chamber between the sleeve and housing that contains a volume of air for contractionally expelling the air into the housing in response to increases in its volumetric capacity resulting upon outward reciprocation of the reciprocating member and expansionally receiving air from the housing in response to decreases in its volumetric capacity upon inward reciprocation of the reciprocating member. Thus, a controlled volume of clean air free of excess moisture is contained in equilibrium between the bladder and the housing to permit normal actuator operation while preventing entrance of debris and excess moisture thereinto through its vent arrangement. A cylindrical cover protects the bladder from degradation by the ambient atmosphere and environment.