JPH02125474U

JPH02125474U -

Info

Publication number: JPH02125474U
Application number: JP3357489U
Authority: JP
Priority date: 1989-03-25
Filing date: 1989-03-25
Publication date: 1990-10-16

Description

[Brief explanation of the drawing]

図は本考案に従つたタンデム型負圧式倍力装置
の一実施例を示す断面図である。１０……タンデム型負圧式倍力装置、１１……
ハウジング、１２……フロントシエル、１３……
リヤシエル、１４……固定壁、２０……フロント
可動壁、２１……ハブ部材、２１ｂ……底壁、２
１ｃ……筒状部、２１ｄ……段付部、２２……プ
レート、２３……ダイアフラム、２３ａ……内周
ビード部、２３ｂ……外周ビード部、２３ｃ……
延出部、３０……リヤ可動壁、３１……ハブ部材
、３１ａ……内孔、３２……プレート、３３……
ダイアフラム、４０……制御弁機構、７０……ケ
ース、１７０……ケース、ｒａ１……フロント変
圧室、ｒａ２……フロント定圧室、ｒｂ１……リ
ヤ変圧室、ｒｂ２……リヤ定圧室。 The figure is a sectional view showing an embodiment of a tandem type negative pressure booster according to the present invention. 10... Tandem type negative pressure booster, 11...
Housing, 12...Front shell, 13...
Rear shell, 14...Fixed wall, 20...Front movable wall, 21...Hub member, 21b...Bottom wall, 2
1c...Cylindrical part, 21d...Stepped part, 22...Plate, 23...Diaphragm, 23a...Inner peripheral bead part, 23b...Outer peripheral bead part, 23c...
Extension portion, 30...Rear movable wall, 31...Hub member, 31a...Inner hole, 32...Plate, 33...
Diaphragm, 40... Control valve mechanism, 70... Case, 170... Case, ra1... Front variable pressure chamber, ra2... Front constant pressure chamber, rb1... Rear variable pressure chamber, rb2... Rear constant pressure chamber.

Claims

[Scope of utility model registration request]

The inside of the housing formed by joining the front shell and the rear shell is connected to a fixed wall, a front hub member disposed in front of the fixed wall, an inner peripheral bead portion of the front hub member, and a bead portion of the inner peripheral portion of the housing that is airtightly attached to the front hub member. A bead portion is disposed behind a front movable wall consisting of a front diaphragm airtightly sandwiched between the fixed wall and the front shell, and the fixed wall to fix the front movable wall airtightly and to The movement is divided into four chambers, a front constant pressure chamber, a front variable pressure chamber, a rear constant pressure chamber, and a rear variable pressure chamber, by a rear movable wall that is airtightly guided by the rear shell and the fixed wall, and the front constant pressure chamber and A control valve that constantly communicates the rear constant pressure chamber with a negative pressure source, and selectively communicates the front constant pressure chamber and the rear constant pressure chamber with the atmosphere in conjunction with a brake pedal. a mechanism, a case member disposed in the front constant pressure chamber and sandwiching the front movable wall between the front movable wall and the rear movable wall; In a tandem negative pressure booster comprising a reaction mechanism that transmits a reaction force to a piston of a master cylinder coupled to a front shell and also transmits a part of reaction force from the piston to the control valve mechanism, the rear movable wall is provided with a cylindrical protrusion extending toward the front movable wall, slidably passing through the inner circumference of the fixed wall in an airtight manner, and having a stepped portion on the inner circumference; The hub member has a stepped portion that is fitted into the protruding portion, forms an annular gap between the hub member and the protruding portion, and extends from the opening of the protruding portion to the stepped portion, and faces the stepped portion in the axial direction. a cylindrical portion is provided, and a bottom wall is provided at an end of the cylindrical portion to be held between the case member and the rear movable wall;
A cylindrical extending portion extending in the axial direction within the gap is provided on the inner periphery of the diaphragm, and the end portion of the extending portion is airtightly sandwiched in the radial direction between the stepped portion and the stepped portion. A tandem type negative pressure booster, characterized in that the inner peripheral bead portion is provided so that the inner circumferential bead portion is provided.