JPH02123458U

JPH02123458U -

Info

Publication number: JPH02123458U
Application number: JP3170189U
Authority: JP
Priority date: 1989-03-21
Filing date: 1989-03-21
Publication date: 1990-10-11

Description

[Brief explanation of drawings]

第１図は本考案に従つた負圧式倍力装置の一実
施例を示す断面図、第２図は本考案の変形例を示
す断面図である。１０……負圧式倍力装置、１１……ボデイ、１
４……パワーピストン、１５……ダイアフラム、
１５ａ……内周縁部、１５ｃ……厚肉部、１５ｄ
……折曲げ部、１６……定圧室、１７……変圧室
、１８……ピストンボデイ、１９……プレツシヤ
プレート、１９ｃ……段部、２３……制御弁。 FIG. 1 is a sectional view showing an embodiment of a negative pressure booster according to the present invention, and FIG. 2 is a sectional view showing a modification of the present invention. 10... Negative pressure booster, 11... Body, 1
4...Power piston, 15...Diaphragm,
15a...Inner peripheral edge part, 15c...Thick wall part, 15d
...Bending portion, 16... Constant pressure chamber, 17... Variable pressure chamber, 18... Piston body, 19... Pressure plate, 19c... Step portion, 23... Control valve.

Claims

[Claims for Utility Model Registration] (1) A power piston that divides the inside of a body into a constant pressure chamber and a variable pressure chamber in collaboration with a diaphragm whose outer peripheral edge is hermetically sandwiched by the body, a piston body having an inner circumferential edge hermetically fitted to an outer circumference thereof and having a built-in control valve for controlling a pressure difference between the constant pressure chamber and the variable pressure chamber; A metal plate is arranged and fitted into the piston body, and whose movement toward the constant pressure chamber with respect to the piston body is restricted by contact between the surface of the piston body facing toward the variable pressure chamber and its inner periphery. In the negative pressure booster configured with a pressure plate, an annular thick part is provided between the inner peripheral edge and the outer peripheral edge of the diaphragm, and the annular thick part is provided between the thick part and the inner peripheral edge. 1. A negative pressure booster comprising a bent portion that can be extended toward the outer circumferential edge so as not to transmit a tensile load applied to the outer circumferential edge to the inner circumferential edge. (2) The negative pressure booster according to claim 1, wherein the pressure plate is provided with a stepped portion that engages with the thick portion of the diaphragm in a radial direction.