Denso Corporation

Advics Co., Ltd.

Takeshi Fuchida

Takashi Murayama

Daizo Oba

Takahiro Yamaguchi

Hiroyuki Shinkai

Takashi Sato

Toshiya Morikawa

Hidemi Ikai

Yoshitake Hisada

Shigeki Torii

Mamoru Sawada

Tomoo Harada

Takashi Satou

Shuichi Yonemura

Yoichi Abe

Hideshi Mori

Yukio Ishikawa

A rotating pumping apparatus is provided which may be employed in an automotive brake system. The rotating pumping apparatus includes a sealing member and an oil seal which are disposed around a pump drive shaft, and lubricating grease disposed between the oil seal and the pump drive shaft. The sealing member is made up of a resinous ring and a rubber cup. The sealing member has formed therein a labyrinthine flow path which extends from the resinous ring to the rubber cup. The labyrinthine flow path is designed to permit fluid to flow therethrough and create the resistance to flow of the lubricating grease to avoid leakage of the grease outside the sealing member.

Rotating pumping apparatus with seal mechanism

A bearing is located with movement of an outer race in the longitudinal direction of a drive shaft being restricted, and the drive shaft is fixed to an inner race with the press fit, so that, it is possible to prevent the drive shaft from escaping. In addition, the inner race is longer than the outer race. Therefore, it is possible to obtain sufficient strength of the press fit of the drive shaft in the inner race while suppressing the size of the outer race (in other words, suppressing the size of the pump device). As a consequence, the size of the pump device can be suppressed while increasing reliability of the function for preventing the drive shaft from escaping.

Pump device

A pump body includes a cylindrical first case for housing the plurality of rotary pumps, a second case located coaxially with the first case, and a disk spring located between the first case and the second case. In addition, a fixing means located at an entrance of the concave portion of a housing presses the second case in the insertion direction of the pump body and fixes the second case.

Vehicular brake device

A motor-driven gear pump assembly includes a rotary shaft rotatably mounted in a housing, and a pump mounted on the rotary shaft. The pump has a pressure chamber. A high-pressure seal is disposed around the shaft between the pump and the motor. A low-pressure seal is provided around the shaft between the high-pressure seal and the motor. An annular oil seal chamber is formed between the high-pressure seal and the low-pressure seal to surround the shaft. A recess chamber is formed around the oil seal chamber. Oil is introduced into the oil seal chamber until the portion of the rotary shaft in the oil seal chamber is completely submerged in the oil introduced while leaving air in the oil seal chamber. The oil in the oil seal chamber thus serves as a seal which positively prevents infiltration of air into the pump. If oil in the pump leaks through the high-pressure seal into the oil seal chamber, the air is compressed, thus absorbing any increase in the volume of oil.

Oil seal arrangement

In a 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 respective reaction forces against the drive shaft to be produced by the high pressure at the respective discharge ports. The respective discharge fluid conduits, in case of the first and second pumps, are located at the points which are opposite each other, more preferably, different at an angle of 180 degrees each other, with respect to the center axis of the drive shaft to limit the bending of the drive shaft. As a method for assembling the pump equipment, the peripheral border between respective cylindrical members piled up for constituting the casing is tentatively welded by laser beam at first and, then, all around the peripheral borders are finally welded.

Pump equipment with plural rotary pumps and method for assembling same

In a radial roller bearing having an outer race and rollers, the outer race has a cylindrical portion and first and second flanges extending radially inward from opposite axial ends of the cylindrical portion. Hardness or strength of the cylindrical portion in a vicinity of the first flange is higher than that in a vicinity of the second flange. A shape of the first flange is different from that of the second flange. When the radial roller bearing is assembled to hold a rotating shaft on which a radial load acts, the outer race is easily oriented in an axial direction of the rotating shaft based on the shape difference between the first and second flanges so that the cylindrical portion in the vicinity of the first flange receives higher bearing pressure due to the radial load. Accordingly, flaking or peeling is unlikely to occur so that life time endurance and strength of the radial roller bearing is improved.

Radial roller bearing, rotating apparatus using same and method of manufacturing the apparatus

In a pump equipment having one or more rotary pumps for 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 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 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 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.

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.

Growing community of inventors

Kariya, Japan

Takeshi Fuchida