Jidosha Kiki Co., Ltd.

Jidosha Kiko Co., Ltd.

Mutsuro Yamakoshi

Kunio Yanagi

Kimio Ishihara

Shozo Sakaguchi

Akihiro Kamiyoshihara

Shinichi Inagaki

The present invention discloses a liquid pressure control device (1) for load responding brake. This liquid pressure control device (1) comprises valve mechanisms (5) and (6) for reducing liquid pressure from a brake master cylinder and transmitting reduced liquid pressure to rear wheel brake cylinders, these operations being performed by opening/closing valves with a pair of plungers (3) and (4) which respond to loads independently of each other by the liquid pressure from the brake master cylinder, and a load sensing mechanism (11) for moving the pressure reducing operation starting points of the valve mechanisms (5) and (6) by applying loads to the plungers according to the movable load amount of a vehicle. A recessed section (14b) is formed in a portion of an equalizer (14) brought into contact with a load sensing lever (13), and a buffer member (19a) made of an elastic material is fixed in this recessed section (14b). During non-operation, the equalizer (14) and the load sensing lever (13) are kept away from each other by the buffer member (19a). During operation, by pressing and deforming the buffer member (19a) with the load sensing lever (13), direct contact is made between the equalizer (14) and the load sensing lever (13). Thus, hitting sounds produced from the load sensing mechanism can be prevented at the time of a sudden brake operation or brake non-operation during traveling of the vehicle, and the durability of the used buffer member can be improved.

Liquid pressure control device for load responding brake

The present invention provides a brake fluid pressure control valve having a plunger 23 slidably fitted in a cylinder hole 22 in a cylinder housing 21 and a retainer 24 which holds the posture of the plunger 23 and seals one end of the cylinder hole 22 by using an O-ring 31 serving as a sealing member, the control valve being characterized in that the plunger 23 is formed with a step 27a, the cylinder housing 21 is provided with an engagement hole 29, which engages with the step 27a and is formed in the direction crossing with respect to the plunger 23, and a pin 30 is inserted in the engagement hole 29 so that the plunger 23 is prevented from coming off by the pin 30. Further, the engagement hole 29 is also used as an air bleeding path adjacent to an installation hole for an air bleeder 40.

Brake fluid pressure control valve

An equalizer 26 is interposed between a load detecting lever 22 and one end of each plunger 3, 4, a clamp member 23 is provided to position the equalizer at a predetermined position of the load detecting lever 22, a connecting portion rotatably connected to a housing 2 concentrically with respect to a support portion 2a supporting the load detecting lever 22 is provided on the clamp member, an arm 24 is formed at the connecting portion of the clamp member 23, and the arm 24 is supported by the support portion 2a of the housing 2 by using a pin 27 common to the load detecting lever 22.

Load response type brake fluid pressure controller

An object of the present invention is to decrease the machining cost and to improve the productivity. A liquid pressure control device (21) for load responding brake comprises a valve mechanism (25), which is slidably disposed in a housing (22), for decreasing the liquid pressure of a master cylinder in a predetermined proportion and transmitting the liquid pressure to a rear wheel brake cylinder by the movement of a plunger (24) operated in response to the liquid pressure from the master cylinder; and a load sensing mechanism (27) in which a load depending on the movable load of a vehicle is applied to the plunger (24) so as to move the pressure decrease operation start point of the valve mechanism (25). The housing (22) is formed by cutting a long material (50) formed by extrusion or drawing to a predetermined length and then by machining the cut material (51).

A proportioning valve of the present invention has a columnar portion protruding at the head of a retainer for slidably retaining a plunger. The outside diameter of columnar portion is set in such a manner that when a retaining ring, which inhibits the movement of the retainer in one direction, is completely set into an annular groove in a valve housing, the retaining ring is positioned around the columnar portion, and when the retaining ring gets out of the annular groove, the retaining ring is positioned at the end of columnar portion. A stopper for the plunger is disposed on the retainer so that a valve element cannot abut against a valve seat when the retainer is located at a position shifting in the output pressure direction.

Proportioning valve

A liquid pressure control device (1) including a valve mechanism for reducing liquid pressure of a brake master cylinder at a predetermined ratio by a pair of plungers (3, 4) moved independently by liquid pressure from the brake master cylinder through ports (7, 8) and for transmitting the reduced pressure to brake cylinders, of right and left rear wheels through ports (9, 10), respectively, and a load sensing mechanism (11) for having a load according to a movable load of a vehicle act on respective plungers (3, 4) so as to move a pressure reduction starting point of the valve mechanism. The load sensing mechanism (11) has a spring (12) connected to an axle side at one end thereof for transmitting energizing force according to the movable load of the vehicle, a load sensing lever (13) pivotally supported on a housing of the valve mechanisms (5, 6) at one end thereof and connected to the other end of the spring at the other end thereof, an equalizer (14) abutting against ends (3a, 4a ) of respective plungers (3, 4), and a clamp member (15) for attaching the equalizer fixedly at a predetermined position of the load sensing lever and preventing the equalizer from coming off due to a large movement of the load sensing lever.

The hydraulic brake pressure control valve is provided including a valve casing mounted on a master cylinder of a hydraulic brake system. A valve piston is provided with a stepped configuration with an enlarged diameter portion and a reduced diameter portion. The valve piston is mounted slidably and longitudinally along the longitudinal bore of the valve casing. The valve piston is normally urged into a non-operating position and is shiftable longitudinally in an opposite direction from the non-operating position under the effect of a difference in the cross-sectional areas of the enlarged and reduced diameter portions, upon which hydraulic brake fluid pressure acts. The stepped valve piston is defined with a brake fluid passage extending longitudinally therein providing communication between brake fluid passages adjacent the reduced diameter portion and the enlarged diameter portion of the stepped valve piston. A fluid valve member is disposed in the fluid passage and is adapted to hold the fluid passage in an open position when the stepped valve piston is in a non-operating position and to cause the fluid valve to be opened and closed when the stepped valve piston operates in a valving manner. An arrangement is provided such that when the fluid valve is brought to either an opened or a closed position an outer wall surface associated with the valve member abuts an inner wall surface of the stepped valve piston.

Hydraulic brake pressure control valve

In a load-sensing proportion valve including a control valve disposed in a hydraulic fluid passage extending from a master brake cylinder to rear-wheel brake cylinders, a plunger adapted to operate the conbtrol valve in response to the output fluid pressure from the master brake cylinder, and a stem formed integrally with a load-sensing lever and adapted to urge the plunger to open the control valve in accordance with a current load of a vehicle, a resilient member is interposed in a working position between the plunger and the stem so as to prevent the occurrence of noises from possible contacts between these plunger and stem, when set together.

Hydraulic brake load-sensing proportion valve with noise prevention means

A muffler device for use in a brake booster system in which there are inserted in an air suction passage cylindrical noise shielding member having at one end an outer flanged portion extending radially outwardly and at the other end an inner flanged portion extending radially inwardly, the circumferential wall of the noise shielding means being defined with an air suction opening; and cylindrical noise absorbing member with a gas permeability being inserted into the inner circumference of the circumferential wall, in such a manner that noises as generated at the valve mechanism during the operation of the brake booster may effectively be prevented from propagating to the outside by aid of the noise shielding member and the noise absorbing member together.

Muffler for brake booster system

An air bleeder is disclosed for a fluid system such as a braking liquid pressure control valve which operates to reduce a braking liquid pressure supplied to a rear wheel cylinder at a given proportion to a braking liquid pressure supplied to a front wheel cylinder as a braking liquid pressure is supplied from a master cylinder. An air bleeder is disposed for use with such a fluid system, in particular, with a fluid system in which a plunger is slidably received in a bore formed in a housing in which a plate is fitted to serve as a stop member and an end of the plunger is maintained in abutment against the plate when it is inoperative. A space which is defined between the periphery of the plunger in the region of its end and the internal surface of the bore and which communicates with a fluid passage extending through the plunger and the plate is sealed against an exterior by a seal member. The air bleeder comprises an air bleeding path formed in the plate so as to extend across the area of contact between the plate and the plunger to maintain the space in communication with the fluid passage. In this manner, a satisfactory air bleeding from the space is assured.

Growing community of inventors

Higashimatsuyama, Japan

Mutsuro Yamakoshi