Patent · US Expired

Rod seal apparatus for cylinder assembly

US6173960A · kind A · utility

3Cited by
3References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 27, 1999
Grant dateJan 16, 2001
Priority date
Expiry dateMay 27, 2019

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16J15/164
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.