Brake servo having an adaptive-flow direct air inlet

• Main Authors: JEAN PIERRE GAUTIER, ULYSSE VERBO
• Format: Patent
• Language: English
• Published: 20.08.1998
• Edition: 6
• Subjects: ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; PERFORMING OPERATIONS; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OFVEHICLES; TRANSPORTING; VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES; VEHICLES IN GENERAL

PCT No. PCT/FR96/00281 Sec. 371 Date Mar. 8, 1996 Sec. 102(e) Date Mar. 8, 1996 PCT Filed Feb. 22, 1996 PCT Pub. No. WO96/29220 PCT Pub. Date Sep. 26, 1996The invention relates to a pneumatic brake booster using two sources of air pressure and comprising a rigid casing (3) divided by a leaktight moving partition (4) into at least two chambers (3a, 3b), it being possible for the moving partition to be urged by a difference, brought about by an actuation of the valve, between the pressures supplied to the chambers in order to drive along a pneumatic piston (5) bearing an operating valve (7), the inside (50) of this piston being separated from the second source by a purification filter (14). The booster of the invention includes shut-off means (16, 51) with controlled opening, installed between the second source of pressure (A) and the inside (50) of the piston and controlling an air intake path (15) which connects the second chamber (3b) to the second source of pressure (A) avoiding passing through the filter (14) and the valve (7), and elastic means (17) which are sensitive to a difference in pressure between the inside of the piston and the second source of pressure, in order to allow selectively the opening of the shut-off means when this pressure difference exceeds a given threshold.