Denso Corporation

Nippondenso Co., Ltd.

Toshiya Morikawa

Takahiro Yamaguchi

Tomoo Harada

Hiroyuki Shinkai

Takeshi Fuchida

Mamoru Sawada

Shuichi Yonemura

Yoichi Abe

Takashi Watanabe

Takashi Sato

Takashi Murayama

Kazutoshi Yogo

Daizo Oba

Takashi Satou

Takahiro Goshima

Takahiro Kiso

Sadayuki Ohno

Hideshi Mori

Koji Okazaki

Masaki Ohoka

In the brake apparatus having a rotary pump, outer and inner rotors of the rotary pump are made of bearing steel and inner and outer teeth portions of the rotors are respectively processed by nitriding hardening or carbo-nitriding hardening. Accordingly, outer circumferential region of the outer teeth portion and inner circumferential region of the inner teeth are constituted by nitrided layer containing 15 to 40 percents retained austenite so that teeth faces of the outer and inner teeth portions in mesh may have higher wear resistance.

Hydraulic circuit having a rotary type pump and brake apparatus for a vehicle provided with the same

In a rotary pump, an outer rotor and an inner rotor are assembled in a casing such that, when a clearance between an inner teeth portion of the outer rotor and an outer teeth portion of the inner rotor is substantially nullified at a first closed gap portion having a maximum volume formed between the inner teeth portion and the outer teeth portion, a clearance between the outer rotor and the casing on a side of the first closed gap portion and a clearance between the outer rotor and the casing on a side of a second closed gap portion having a minimum volume, become substantially an equivalent interval. As a result, the outer rotor and the casing can be brought into contact with each other on the side of the second closed gap portion rather than the central axis of the inner rotor. Even in a high pressure discharge operation, the outer rotor is not locked by being squeezed between the inner rotor and the casing.

Rotary pump and braking device using same

In a pump equipment having one or more rotary pumps for a hydraulic circuit, the intake port is communicated with the shaft hole for inserting the drive shaft and fluid flows through the shaft hole to a fluid groove provided in inner surfaces of the pump room for the purpose of lubrication. To prevent fluid leakage to the outside, first and second oil seals are disposed for filling the clearance between the drive shaft and the shaft hole and, preferably, a communicating conduit is provided between the first and second oil seals to transmit the fluid leaked through the first oil seal to a low pressure fluid conduit of the hydraulic circuit. In particular, in the pump equipment having plural rotary pumps, the respective discharge ports of the rotary pumps are located at the points which are nearly symmetrical with respect to the center axis of the drive shaft to counterbalance each other, the reaction forces against the drive shaft to be produced by the high pressure at the respective discharge ports.

Pump equipment and method for assembling same

In the rotary pump, a sealing member is provided at a clearance between a casing and axial end surfaces of the inner and outer rotors, the sealing member extending from an outer circumference of the outer rotor, via the inner rotor between a drive shaft and a discharge port, to another circumference of the outer rotor so that brake fluid communication from the discharge port to an intake port may be prevented, but the brake fluid communication between the outer circumference of the outer rotor and almost all of teeth gap portions on a discharge port side and, further, between almost all of teeth gap portions on an intake port side and a clearance between the drive shaft and the inner rotor may be allowed.

Rotary pump with better fluid sealing structure and brake apparatus having same

A brake control apparatus for automotive vehicles is provided which has two separate hydraulic brake lines leading to wheel cylinders and performs a brake assisting operation to hold the wheel cylinder pressure higher than the master cylinder pressure in each of the hydraulic brake lines when a brake pedal is depressed by a vehicle operator. The brake control apparatus also includes a fluid pressure difference regulator which regulates a pressure difference between the two hydraulic brake lines so as to fall within a given allowable pressure range, thereby minimizing adverse effects on the brake assisting operation which are caused by electric and/or mechanical performance difference between the two hydraulic brake lines.

Hydraulic structure of automatic brake control system

A hydraulic circuit has a rotary type pump comprising a rotor rotating with a driving shaft and a casing which holds the rotor and the driving shaft. The casing further comprises an inlet port through which fluid is introduced to spaces formed by the rotor, an outlet port through which fluid is discharged from the spaces, and a hydraulic path for leading fluid from clearance around said driving shaft to the outside of the casing. A reservoir is provided to store fluid coming through the hydraulic path. A return conduit is disposed between the reservoir and an upstream side conduit connected to the inlet port in order that fluid stored in the reservoir is returned to the upstream side conduit. In the return conduit, a check valve is disposed to prevent the reverse flow of fluid from the upstream side conduit to the reservoir.

Hydraulic circuit having a rotary type pump and brake apparatus for a

An anti-skid control apparatus which can be manufactured at low cost by reducing the number of valves that control the flow of brake fluid has a master cylinder, a first conduit which includes a first branch conduit and a second branch conduit, a cut-off valve, a first control valve installed in the second branch conduit, a second control valve installed in the second branch conduit and connected to a second wheel cylinder, a second conduit connecting the second control valve and a reservoir, a third control valve installed in the second conduit, and a pump connected in parallel with the third control valve. This arrangement permits flexible anti-skid braking operations using a reduced number of components.

Anti-skid control apparatus

Growing community of inventors

Kariya, Japan

Toshiya Morikawa