Title:
HYDRAULIC DEVICE FOR DRUM BRAKE
Document Type and Number:
Japanese Patent JP2018003996
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a hydraulic device for a drum brake applied with an annular seal member for use in sealing against working fluid that restricts its slide contacting action against a piston or a cylinder by high pressure.SOLUTION: An annular seal member 52 has a first annular recess surface 52c formed at an end surface of an oil chamber 54 and a second annular recess surface 52d formed at an end surface opposite to the first annular recess surface 52c. The second annular recess surface 52d still keeps a shape that is not closely adhered to a side wall of an annular groove 50a when the annular seal member 52 is resiliently deformed under application of the maximum pressure of the working oil supplied to the oil chamber 54. With this arrangement as above, since it is possible to prevent high pressure from transmitting to the outer peripheral surface of the annular seal member 52, occurrence of scar caused by the press contact of foreign material is restricted and damage of the annular seal member 52 is restricted.SELECTED DRAWING: Figure 5
Inventors:
KOMODA KAZUYASU
Application Number:
JP2016133709A
Publication Date:
January 11, 2018
Filing Date:
July 05, 2016
Export Citation:
Assignee:
HOSEI BRAKE IND
International Classes:
F16D65/22; F16D51/20; F16J15/18; F16J15/3236
Attorney, Agent or Firm:
Haruyuki Ikeda
Kojiro Ikeda
Kojiro Ikeda