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:
Jan. 16, 2001
Filed:
May. 27, 1999
Yasuo Inose, Kanagawa-ken, JP;
Hiromi Machida, Kanagawa-ken, JP;
Tokico Ltd., Kawasaki, JP;
Abstract
There is provided a seal apparatus for sealing against a rod, comprising a double seal including a rod seal and an O-ring which serves as a back-up ring for the rod seal. The double seal is provided in an annular groove formed on an inner circumferential surface of a rod guide which guides a sliding motion of the rod. An annular partition wall extends from the rod guide so that a force applied to the rod seal from the O-ring is shared between the rod seal and the partition wall. An annular protrusion is formed on a front end surface of the partition wall, so that when the rod seal is pressed with a large force toward the low-pressure side, the protrusion bites into a stepped surface of the rod seal and a front end surface of the rod seal is brought into contact with a low-pressure-side seal-bearing surface of the rod guide. The force applied to the rod seal is distributed to two sites. This provides an ideal contact surface pressure distribution with respect to a surface of contact between the rod seal and the rod, without being affected by a dimensional error and a difference in thermal expansion.