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:
Dec. 19, 1989
Filed:
Apr. 03, 1989
Toshimitsu Shida, Fujisawa, JP;
Fuji Valve Co., Ltd., Tokyo, JP;
Abstract
The present invention relates to a hydraulic valve lash adjuster which is capable of storing a large quantity of oil therein and exhibits high resistance to wear. In the valve lash adjuster in accordance with the invention, the plunger comprises an upper plunger portion and a lower plunger portion, at least a portion of a partition member extends over the joint between the upper and lower plunger portions, and the upper plunger portion being welded to the lower plunger portion by projection welding so that the partition member is deformed inward by bulging of the welded portion to fix the partition member within the plunger. Accordingly, the upper and lower plunger portions are welded together by projection welding, and simultaneously the partition member is sealingly fixed within the plunger. The plunger thus formed is surface hardened by quenching or carburizing. With the above construction of the invention, therefore, the hardness of the outer surface of the plunger is not impaired and the residual stresses generated by welding do not degrade the resistance to wear and fatigue.