Abstract: An improvement of a hydraulic pressure control device for a double piping type hydraulic system for vehicle brakes not only performs braking pressure control over both of two independent hydraulic pressure channels but also is capable of transmitting the same degree of hydraulic pressure to the rear wheels of a vehicle as the front wheels thereof by releasing one hydraulic pressure channel from a control action when the other hydraulic pressure channel becomes defective, so that insufficiency in the braking force on the whole vehicle resulting from such a defect can be effectively compensated.

Abstract: In a pin-slide type disc brake, the caliper of the disc brake is prevented from dropping or turning on a slide pin due to its own weight during replacement of the friction pads of the disc brake by providing a fitting hole in a part of a support straddling the disc in the radial direction of the disc and in the vicinity of a caliper guide mechanism located on the upper side of the support. A rigid rod is fitted into the hole and arranged to have, for example, the inner wall of the disc straddling portion of the caliper come to engage it to thus prevent the caliper from dropping when it is turned about the slide pin.

Abstract: An improvement on a caliper guiding mechanism for a disc brake in which an auxiliary slide pin is arranged to be slidable in metallic contact, instead of conventional elastic contact, in the same manner as a main slide pin to an extent corresponding to a distance of a gap normally existing between a disc and each of friction pads. The invented arrangement is such that there is no difference between these slide pins in resistance to caliper sliding movement to prevent uneven wear and dragging of the friction pads. Despite of the sliding arrangement, the auxiliary slide pin is capable of absorbing a certain degree of machining error or a change in the parallel relative positions of the sliding pins caused by a torque during brake application.

Abstract: In a drum brake, a wheel cylinder is located between a pair of adjacent shoe ends for a pair of brake shoes and a piston inserted into the wheel cylinder is slidably engaged through an anchor provided on a backing plate and further the piston is provided with a flange on the side thereof pressing a brake shoe so that the anchor is interposed between the flange of the piston and the wheel cylinder, and, furthermore, a strut is located between the other pair of adjacent shoe ends for the pair of the brake shoes in order to lighten a weight of the brake and facilitate a disassembly and assembly of the brake.

Abstract: An antiskid pressure reducing device for a vehicle which lowers braking pressure to prevent wheels of the vehicle from coming into a locked state during brake application to the vehicle. A plunger, which moves back and forth as differential pressure between a high pressure chamber and a low pressure chamber increases or decreases, is arranged to slide to some extent within a cylinder during brake application which is frequently performed so that the plunger can be prevented from being stuck to the cylinder by rust to keep it unfailingly slidable for antiskid pressure reducing operations.

Abstract: A device for automatically adjusting a braking clearance for a disc brake in which at least one friction pad is directly placed in frictional engagement with a disc rotor by means of a piston. The device comprises an adjusting bolt, stop means for controlling movement of the adjusting bolt, an adjusting nut threaded on the adjusting bolt, first spring means retained between a main piston and the adjusting nut, a stepped piston slidably mounted within the main piston, frictional surfaces opposedly disposed on the stepped piston and the adjusting nut, and second spring means for biasing the stepped piston. When pressure within the liquid chamber of the cylinder reaches a predetermined level, the stepped piston is moved against the force of the second spring means so that both frictional surfaces are engaged to impede rotation of the adjusting nut.

Abstract: A tandem master cylinder device having a cylinder body slidably receiving therein a driving piston and a floating piston so as to define a first liquid chamber and a second liquid chamber, the device housing a liquid pressure control valve by which a differential in output liquid pressure between a front brake pressure and a rear brake pressure is produced. A stepped piston is mounted on the floating piston to open and close a poppet valve.

Abstract: A friction material of the present invention is directed to secure a required value of an initial effect and the following effects after a friction hysteresis during a brake operation by adding 20-60 wt. % of a high carbon iron powder instead of a ceramic powder in the conventional friction material and also succeed in improving a wear resistance at a high temperature by further adding 0.5-10.5 wt. % of antimony trioxide as a flame retarding material.

Abstract: An improvement over the caliper carrying structure of a pin-slide type disc brake. A caliper straddling a disc is arranged to be slidable in the axial direction of the disc through a pair of slide pins. At least one of the slide pins is secured either to the caliper or to a fixed support disposed at the periphery of the disc and is arranged to be in slidable engagement through a rigid sleeve with an opening formed either in the support or in the caliper. The rigid sleeve is prevented from pulling off its position by a flange formed at one end thereof and is kept between the support and the caliper. The outer and inner circumferential faces of the rigid sleeve are slidable both on the opening and on the slide pin. With two sliding parts provided in this manner, each sliding part is provided with a sealing device independently of the other for protection from the outside.

Abstract: An antiskid device which causes braking pressure to decrease when wheel velocity suddenly drops during a braking operation on a vehicle and then allows the braking pressure to increase upon restoration of the wheel velocity. The antiskid device is equipped with a circuit for producing a tracking acceleration signal VT1 which increases at a predetermined rate from a minimum value of wheel velocity during a recovering process of the wheel velocity and also with a comparator which compares the wheel velocity Vw with the tracking acceleration signal VT1. The braking pressure is allowed to quickly increase when the comparator is in operation.

Abstract: An automatic adjuster which readily permits manual adjustment of a drum brake by manually rotating an adjuster screw only. For normal automatic adjustment, an adjuster nut makes outward screwing rotation with the adjuster screw not allowed to rotate when the extent of forward movement of the adjuster nut comes to exceed a predetermined value during brake application. Manual adjustment is performed by rotating the adjuster screw to screw it outward or inward while the adjuster nut is not allowed to rotate.

Abstract: A disc brake of a type incorporating therein a hydraulic pressure generator, the disc brake having a pair of friction pads disposed on both sides of a disc to be braked to confront each other across the disc; a guide shaft; and a caliper which is provided with a thrusting piston incorporated therein for pushing one of the friction pads against the disc with hydraulic pressure and is arranged to push the other friction pad against the disc as said caliper is moved on the guide shaft by a reaction to the thrusting action. The hydraulic pressure generator is disposed within the guide shaft and is provided with a cylinder which is formed within the guide shaft, a hydraulic pressure generating piston which slidably engages the cylinder and a hydraulic pressure generating chamber. The hydraulic pressure generating chamber communicates, through a passage means, with a hydraulic operation chamber which exerts hydraulic pressure on the thrusting piston.

Abstract: A friction pressure welding method in which, for a friction pressure welding between a pin and a recess of a support, the recess is arranged to have an inner diameter slightly larger than an outer diameter of the pin and a cap nut fitted to a collet chuck of a friction pressure welding machine is provided with an extension at a front thereof so as to control a curl projecting from an end surface of the pin at a certain height during operation of the friction pressure welding such that edges produced on the pin are forcibly pressed onto the recess and a welding area between the curl portion and the recess is increased, thereby enhancing a fatigue strength of the joint portion and increasing a strength against vibration exceedingly.

Abstract: A disc brake is provided with a fluid pressure operating mechanism for a service brake and concurrently with a mechanical operating mechanism for a parking brake. A parking lever of the parking brake is connected to an adjusting bolt through a spindle and a connecting link and further connected to a piston slidable in a cylinder through a sleeve nut. The adjusting bolt is prevented from rotation by a stopper plate fixed to the cylinder. The adjusting bolt and the sleeve nut are connected by thread and provided therebetween with a stopping means of rotation which allows a forward rotation of the sleeve nut toward a disc but limits a retracting rotation of the sleeve nut from the disc. The stopping means of rotation is provided with a locking means which effectively prevents a retraction of the sleeve nut. A clearance between friction pads and the disc is automatically adjusted by the fluid pressure operating mechanism when linings of the friction pads are worn more than a predetermined amount.

Abstract: Construction of a seal arrangement for a sliding part of a pin slide type disc brake having a boot attached to the edge of an open end of a cylindrical portion of a caliper to slidably engage the outer circumferential face of a slide pin in an airtight manner. The boot is arranged to have the inner circumference of one end part thereof elastically expandable. The slide pin is provided with a tapered flange part at one end thereof in such a way as to expand and enlarge the end part of the boot. When the slide pin is inserted to a full extent into the cylindrical portion of the caliper, the tapered flange part causes the end of the boot to enlarge to allow an increased portion of air pressure which is increased within the cylindrical portion of the caliper by the insertion of the slide pin to escape to the inside of the boot through an air flow passage provided in the tapered flange part of the slide pin.

Abstract: A deceleration detecting type proportioning valve for a vehicle arranged in combination with a deceleration detecting valve. Under a no load or light load condition of the vehicle, when deceleration caused by a braking operation reaches a preset value, a deceleration detecting valve is closed. Following this, the proportioning valve which is by-pass connected to the deceleration detecting valve performs proportioning control to provide a controlled hydraulic brake pressure for each rear wheel cylinder to prevent locking of rear wheels. Under a maximum or heavy load condition, even when the deceleration detecting valve closes, the proportioning valve serves to open the hydraulic brake pressure passage to ensure communication between a master cylinder and the rear wheel cylinder to effect increase in hydraulic brake pressure for the latter to the same degree as front wheel cylinders so that insufficiency in the braking force on the rear wheels can be prevented.

Abstract: A deceleration sensing type proportioning valve for oppositely distributing front and rear wheel braking forces in a vehicle. A valve seat is arranged to follow the movement of an adjustment piston in such a way as to increase the degree of compression of a control spring before a plunger comes into contact with the valve seat. The piston and the plunger move in the same direction to permit arrangement of a valve body portion of the plunger to be carried by the adjustment piston in an embracing manner for reduction in size of the whole proportioning valve assembly.

Abstract: A disc brake of a tilting type wherein a caliper comprising a pad pushing mechanism disposed on one side of a disc and a reaction part disposed on the other side of the disc to receive a reaction force developed by the action of the pad pushing mechanism to push a pair of friction pads against both sides of the disc, the caliper being arranged to sway on a support shaft disposed in parallel with a tangential direction of the disc.

Abstract: A disc brake of a type using pins for guiding a caliper in the axial direction of a rotor. A rigid sleeve having an elastic annular member inserted and secured to the inner circumference thereof is provided at a base portion formed on one side of the caliper or a support; while a guide pin which is secured to the other side of the caliper or support is slidably inserted through the elastic annular member.

Abstract: A pad clip for disc brakes wherein one side portion of the pad clip is attached to the backing plate of a friction pad and another side portion of the pad clip has an end projecting to an allowable limit of wear of the lining of a friction pad. The pad clip produces an audible warning sound when the projecting end portion of the pad clip is resiliently pressed against the disc during braking after the lining of the friction pad has worn to the allowable limit. The projecting side portion of the pad clip resists movement in a direction away from the plane of the disc so as to prevent failure of the warning sound activation while still providing sufficient resilience to bias the disc.