Abstract: A vacuum type booster which includes a booster piston reciprocatively movable in a shell, a valve sleeve for a control valve fitted to the booster piston and having a disengagement preventive flange superposed on the piston, and a clamp plate engaged with pawls formed by cutting and bending portions of the booster piston for clamping the flange to the booster piston. The booster piston includes pairs of reinforcement ribs which cross the turning direction of the clamp plate and sandwich cutout holes resulting from formation of the pawls. A pair of the ribs on the rear side of the turning direction of the clamp plate permit the clamp plate to turn in a direction for engagement with the pawls and inhibits the clamp plate from turning in the disengaging direction. A space is provided between the outer peripheral part of the disengagement preventive flange and an engagement piece jointing part of the clamp plate body.

Abstract: An improved self-compensating device for a drum brake of the type including a first member and a second member which together define a hydraulic chamber in a wheel cylinder, said first and second members being slidably but non-rotatably arranged relative to one another so that brake shoes are actuated by displacement of the members away from one another which is initiated by hydraulic pressure introduced into the hydraulic chamber.

Abstract: In the assembly of a master cylinder and an oil-hydraulic booster connected to the rear thereof, the master cylinder has an axial bore consisting of a forward, small-diameter bore section and a rearward, large-diameter bore section and the master cylinder piston in the master cylinder includes a small-diameter section slidably fitted in the small-diameter bore section of the master cylinder and a large-diameter section slidably fitted in the large-diameter bore section thereof. The forward end portion of the piston in the oil-hydraulic booster is formed smaller in diameter than the large-diameter bore section of the master cylinder and is arranged proximate the large-diameter section of the master cylinder piston in the master cylinder so as to enter the large-diameter bore section of the master cylinder when the booster piston is advanced.

Abstract: A mechanically-operated drum brake device which comprises a pair of brake shoes each coming in contact with an anchor at one end portion on the same side and engaging with a floating type actuator and a brake lever rotatably supported on the actuator at their other end portions, respectively. There is provided structure for holding in place the brake shoes and the actuator relative to a back plate at a predetermined distance therebetween in the axial direction of a brake drum. There is also provided a stop member to control the inward contracting movement of the brake shoes when the brake is released.

Abstract: A hydraulic pressure source device for hydraulic boosters, comprising a hydraulic pump connected via a high-pressure oil passage to an input port of a hydraulic booster and a proportional reducing valve serving as a regulator interposed in the high-pressure oil passage, wherein the proportional reducing valve acts to reduce the pressure above a set level fed from the pump at certain reduction ratio and transmit it to the booster, the valve having a piston which is retractable beyond a valve-closing position to enlarge the volume of an output hydraulic chamber of the valve. Such retracting motion of the valve piston attenuates any impact which may be caused by kickback phenomenon occurring during operation of the booster.

Abstract: A master cylinder-reducing valve assembly has a master cylinder and a reducing valve for transmitting output hydraulic pressure from the master cylinder to a rear wheel brake at a reduced level. The reducing valve includes a valve housing provided on the master cylinder and having an inlet communicating with the output port of the master cylinder and an outlet communicating with a rear wheel brake. A pressure receiving piston is slidably received in the valve housing to divide the interior of the housing into an input hydraulic chamber communicating with the inlet and an output hydraulic chamber communicating with the outlet. The pressure receiving piston has a communication bore connecting between the input and output hydraulic chambers. A valve member is disposed in the input hydraulic chamber to open and close the communication bore. A valve spring is received in the valve housing and biases the valve member toward the pressure receiving piston.

Abstract: An improved quick fill type master cylinder having a structure in which a piston consisting of a smaller diameter piston portion and a larger diameter piston portion is slidably fitted into a stepped cylinder bore to define a hydraulic pressure chamber as well as a hydraulic oil supply chamber therein, a relief port opening to the hydraulic pressure chamber and a supply port opening to the hydraulic oil supply chamber are placed in communication with an oil reservoir via a hydraulic oil flow passage formed longitudinally in a cylinder casing, and a valve device is incorporated in the hydraulic oil flow passage. The hydraulic oil flow passage is formed by drilling and the like from the rear end face of the cylinder casing and a valve chamber of the valve device is provided in the oil flow passage near outside opening thereof.

Abstract: A tandem master cylinder for an automobile disclosed herein includes a cylinder body having a cylinder bore, a first and a second pistons slidable in the cylinder bore and axially apart from each other, a first and a second power chambers defined, independently from each other, in the cylinder bore by the first and second pistons, and an auxiliary reservoir formed integrally with the cylinder body at its upper side adjacent the first power chamber. The auxiliary reservoir has a first and second reservoir chambers separated from each other by a partition and both connected with a main reservoir. The first power chamber is connected with the first reservoir chamber through a pair of first vent and supply ports. The second power chamber is connected with the second reservoir chamber through an oil passage which is formed in the cylinder body and which uprises in the direction from the latter to the former.

Abstract: In the assembly of a master cylinder and an oil-hydraulic booster connected to the rear thereof, the master cylinder has an axial bore consisting of a forward, small-diameter bore section and a rearward, large-diameter bore section and the master cylinder piston in the master cylinder includes a small-diameter section slidably fitted in the small-diameter bore section of the master cylinder and a large-diameter section slidably fitted in the large-diameter bore section thereof. The forward end portion of the piston in the oil-hydraulic booster is formed smaller in diameter than the large-diameter bore section of the maste cylinder and is arranged proximate the large-diameter section of the master cylinder piston in the master cylinder so as to enter the large-diameter bore section of the master cylinder when the booster piston is advanced.

Abstract: A tandem master cylinder for an automobile disclosed herein includes a cylinder body having a cylinder bore, a first and a second pistons slidable in the cylinder bore and axially apart from each other, a first and a second power chambers defined, independently from each other, in the cylinder bore by the first and second pistons, and an auxiliary reservoir formed integrally with the cylinder body at its upper side adjacent the first power chamber. The auxiliary reservoir has a first and second reservoir chambers separated from each other by a partition and both connected with a main reservoir. The first power chamber is connected with the first reservoir chamber through a pair of first vent and supply ports. The second power chamber is connected with the second reservoir chamber through an oil passage which is formed in the cylinder body and which uprises in the direction from the latter to the former.

Abstract: A hydraulic pressure source device for supplying an actuating hydraulic pressure to an automotive booster, having an accumulator and a hydraulic pump, the pump being interposed in a low-pressure oil passage leading from the control valve of a hydraulic power steering device to an oil tank. In the oil passage is also interposed an electromagnetic valve which is adapted to be opened and closed under control of an intermittent actuator which intermittently energizes the electromagnetic valve when sensing a pressure in the accumulator below a preset level. The pump is actuated by the hydraulic oil which is discharged into the low-pressure oil passage after having actuated the control valve through intermittent opening and closing operation of the electromagnetic valve to replenish the accumulator with the hydraulic pressure.

Abstract: A disc brake device including a piston, an automatic adjuster and a sleeve piston within the cylinder of a caliper body, wherein braking and automatic braking-gap adjustment are achieved by a hydraulic input, and said piston is pushed by a mechanical input through said sleeve piston and said automatic adjuster for braking.

Abstract: An assembly of a vacuum booster device and a master cylinder comprising a booster shell composed of front and rear halves and a brake master cylinder body which are together combined by the aid of tie rods extending through the booster shell, and a booster piston accommodated in the shell so that the load on the booster shell is removed, any means for fastening the opposite edge portions of both the shell halves is eliminated and, accordingly, outside diameter of the shell is decreased without lowering its strength. Furthermore, retaining ring fitted in the tie rod effective in preventing the shell from separation enables both the constructing and separating works of the assembly easier.

Abstract: A vacuum type brake booster device comprising a booster shell, a booster piston accommodated in the booster shell, a piston diaphragm working together with the booster piston for dividing the booster shell into both front and rear working chambers, and tie rods extending through the piston and the diaphragm for connection of the front and rear walls of the booster shell. Circumferential positioning devices are arranged between the booster piston and piston diaphragm and between the piston diaphragm and booster shell, respectively, so that the piston can correctly be adapted to the shell. Accordingly, the booster piston can be operated freely from interference of the tie rods. Furthermore, the piston diaphragm can be prevented from unnecessary forces due to the pressure difference between both the working chambers by the aid of thin-wall portions arranged in the piston diaphragm.

Abstract: A vacuum source device of vacuum booster is disclosed. The device includes an air ejector having an air inlet communicated with the atmosphere, an air outlet connected to a vacuum pick-up port opening to the portion of the intake system of an internal combustion engine downstream of a throttle valve, and a pressure reduction chamber connected to a vacuum chamber of the vacuum booster. A by-pass passage connecting between the vacuum pick-up port and the vacuum chamber of the vacuum booster by detouring the diffuser of the air ejector imposes a smaller flow resistance than the diffuser. A first check valve is disposed in the by-pass passage, while a second check valve is disposed between the by-pass passage and the vacuum chamber.

Abstract: Disclosed is an improved device for controlling hydraulic pressure for braking a vehicle of the type including a pressure reducing valve disposed midway of an oil passage extending between an output port of a master cylinder and a rear wheel brake, said pressure reducing valve being adapted to proportionally reduce hydraulic pressure from the output port and then transmit reduced hydraulic pressure to the rear wheel brake. The improvement consists in that a pneumatic spring incorporated in a suspension system for determining hydraulic pressure at which the pressure reducing valve initiates pressure reducing function in dependence on the weight of cargoes loaded on the vehicle is operatively connected to a valve body of the pressure reducing valve in such a manner as to bias the valve body in the valve opening direction.

Abstract: A vacuum booster device which is mainly used to operate a master cylinder for hydraulic brakes or the like of automobiles. The device is so constructed that the inner peripheral bead of the diaphragm disposed within the booster shell and the clamping band adapted to clamp the bead tightly are fitted in the annular fitting groove formed in the rear surface of the booster piston, a part of the inner peripheral bead is formed as a thin-walled elastic valve portion which is in close-contact with the inner surface of the annular fitting groove in a separable manner and which engages with the notched recess formed in the rear side wall of the fitting groove, and the relief is provided between the valve portion and the clamping band to allow deformation of the elastic valve portion. Thus, when the pressure within the first working chamber is increased, air can be discharged from the first working chamber to the second working chamber through a gap made in the relief region due to deformation of the valve portion.

Abstract: A vacuum booster device which comprises a booster shell; a booster piston axially slidably accommodated in the booster shell and having a central boss portion and a disc portion around the outer circumference of the boss portion; and a diaphragm superposed on the rear surface of the disc portion and having an inner circumferential bead fitted to the central boss portion of the booster piston and an outer circumferential bead fitted to the circumferential wall of the booster shell. The booster piston and the diaphragm cooperate with each other to divide the interior of the booster shell into a front side first working chamber communicated with a vacuum supply source and a rear side second working chamber selectively communicated with the first working chamber or the atmosphere via a control valve operatively connected to an input member. The front and rear walls of the booster shell are connected to each other by tie rods extending through the disc portion of the booster piston and the diaphragm.

Abstract: A vacuum type brake booster device comprising a first and a second working chambers defined in a booster shell by a booster piston, tie rods extending through the booster piston for connection of the front and rear walls of the booster shell so as to support loads on the booster shell, flexible bellows surrounding each of the tie rods and having opposite ends fixed respectively to the tie rod and the booster piston so that the inside of the bellows is communicated to the second working chamber, and an adjustable stop mechanism provided on an input rod for adjusting a retraction limit of the latter, whereby a control valve is held in a neutral position to keep the second working chamber out of communication with the first working chamber and the external atmosphere so that the bellows becomes expansive owing to a pressure difference between the working chambers for getting out of contact with the tie rod and, accordingly, for keeping the movement of the booster piston undisturbed.

Abstract: An automotive tandem type master cylinder comprising a cylinder body mounted in a frontwardly upwardly inclined manner for increasing the effective engine room space under the cylinder body, and an oil reservoir disposed at rearward, or lower position on the cylinder body for avoiding an increase in height of the hood. An oil passage is formed in the cylinder body in a rearwardly upwardly inclined manner for eliminating air bubbles in working fluid, and a mounting flange projects at the rear end of the cylinder body perpendicularly to the cylinder axis, whereby the cylinder body can be made easily and be shortened in its overall length.