Abstract: 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.

Abstract: A rotating pump includes an outer and an inner rotor disposed in a casing with a gap between the casing and the outer rotor. The rotating pump also includes a first and a second sealing member in the casing to define a low-pressure region and a high-pressure region within the gap. Each of the first and second sealing members is made up of a seal functioning portion and an elastically pressing portion. The seal functioning portion includes a resinous member and a deformation-suppressing member. The resinous member contacts the outer rotor and a low-pressure side inner surface of the casing to establish a difference in pressure between the low-pressure region and the high-pressure region. The deformation-suppressing member works to stop the resinous member from deforming undesirably. This minimizes the risk of breakage of the resinous member and enables the rotating pump to discharge the fluid at an increased pressure.

Abstract: 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.

Abstract: A liquid seal has an annular lip portion and an annular fixing portion to be fixed to an inner peripheral surface of a shaft hole, in which the lip portion is connected to the fixing portion and is provided so that a tip thereof is extended in an axial direction, a spring pressing a seal lip against an outer periphery of the rotation shaft is fitted onto the lip portion. The seal lip forms a mountain shape in which an edge of the apex in the cross section, which is cut along a plane passing through a center axis of the seal, protrudes to the inner diameter side, and the pressure center of the seal lip due to the spring is disposed between the tip side of the lip portion further than the edge of the apex of the mountain of the seal lip in the axial direction.

Abstract: 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.

Abstract: 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.

Abstract: 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 51c 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 51c 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.