Abstract: The present invention is to provide a vehicle-mounted apparatus having a biasing structure using a coil spring capable of reducing a lateral force of a coil spring that is applied to a biasing target member. When N1, n1, N0, and n0 represent the number of effective turns when the relief valve spring 37 is set in a valve hole 34 of a spool 29 in a compressed state, a value of an integer of N1, the number of effective turns when a length of the relief valve spring 37 is a natural length, and a value of an integer of N0, respectively, the spring 37 satisfies an equation 1: 0?N1?n1?0.25 or an equation 2: 0.75?N1?n1<1.

Abstract: In a variable displacement vane pump, a cam profile of a cam ring includes a deviation region deviating from a perfect-circle cam profile outwardly in a radial direction regarding a rotational axis of a driving shaft in an intake region.

Abstract: Provided is a variable displacement vane pump which is capable of reducing fluctuation in discharge rate. In the variable displacement vane pump, a first straightening vane 33 closest to one end-side opening 14a of a discharge passage 14 among a plurality of straightening vanes 33, 34 and 35 arranged within the discharge pressure chamber 202 is located so as not to face a communication hole 32 of a pressure plate 2c.

Abstract: Provided is a variable displacement vane pump which is capable of reducing fluctuation in discharge rate. In the variable displacement vane pump, a first straightening vane 33 closest to one end-side opening 14a of a discharge passage 14 among a plurality of straightening vanes 33, 34 and 35 arranged within the discharge pressure chamber 202 is located so as not to face a communication hole 32 of a pressure plate 2c.

Abstract: The present invention is to provide a vehicle-mounted apparatus having a biasing structure using a coil spring capable of reducing a lateral force of a coil spring that is applied to a biasing target member. When N1, n1, N0, and n0 represent the number of effective turns when the relief valve spring 37 is set in a valve hole 34 of a spool 29 in a compressed state, a value of an integer of N1, the number of effective turns when a length of the relief valve spring 37 is a natural length, and a value of an integer of N0, respectively, the spring 37 satisfies an equation 1: 0?N1?n1?0.25 or an equation 2: 0.75?N1?n1<1.

Abstract: A power source control device includes a charging state detector configured to detect a charging state of a drive battery mounted on an electric vehicle and a power source mode switch configured to switch a power source mode of the electric vehicle, wherein the power source mode switch configured to switch the power source mode to an OFF mode in a case that charging of the drive battery is stopped while the power source mode is set at an ON mode.

Abstract: A power source control device includes a charging state detector configured to detect a charging state of a drive battery mounted on an electric vehicle and a power source mode switch configured to switch a power source mode of the electric vehicle, wherein the power source mode switch configured to switch the power source mode to an OFF mode in a case that charging of the drive battery is stopped while the power source mode is set at an ON mode.

Abstract: A pump device 1 includes a relief valve 42 having a ball 45 and a valve seat 44. The valve seat 44 has a ring-shaped seat surface 52 having a wide portion 52a and a narrow portion 52b on which the ball 45 is seated. Upon valve opening, the ball 45 is pressed in a valve opening direction by a pressing force F1 according to a pressure P of working fluid while being pressed against the wide portion 52a. The ball 45 rolls on the seat surface 52 upon the valve opening while continuing or keeping contact with the wide portion 52a. At this time, the ball 45 is stably held with the ball 45 contacting the wide portion 52a of the seat surface 52. Noise of the relief valve 42 caused by vibration of the ball 45 is therefore suppressed.

Abstract: An object of the present invention is to provide a variable displacement vane pump capable of further reducing a pulse pressure. A vane pump (1) includes a cam ring (33). The cam ring (33) is annularly formed, and defines a plurality of pump chambers (38) on an inner peripheral side thereof in cooperation with a rotor (31) and vanes (32).

Abstract: A pump device 1 includes a relief valve 42 having a ball 45 and a valve seat 44. The valve seat 44 has a ring-shaped seat surface 52 having a wide portion 52a and a narrow portion 52b on which the ball 45 is seated. Upon valve opening, the ball 45 is pressed in a valve opening direction by a pressing force F1 according to a pressure P of working fluid while being pressed against the wide portion 52a. The ball 45 rolls on the seat surface 52 upon the valve opening while continuing or keeping contact with the wide portion 52a. At this time, the ball 45 is stably held with the ball 45 contacting the wide portion 52a of the seat surface 52. Noise of the relief valve 42 caused by vibration of the ball 45 is therefore suppressed.

Abstract: A variable displacement vane pump including a relief valve which includes a valve bore, a spherical valve element in the valve bore, a valve seat fixed onto one axial side of the valve bore and having a through hole and an annular seat surface on which the valve element is seated when the relief valve is in a closed position, a coil spring disposed on the other axial side of the valve bore, and a valve element retainer disposed between the valve element and the coil spring, wherein the seat surface is configured such that when the relief valve is in the closed position, a center of the valve element is located offset from a central axis of one winding seating portion of the coil spring which is disposed on an opposite side of the seat surface, in a radial direction of the valve bore.

Abstract: A variable displacement pump includes: a pump body; a rotor; a cam ring; inlet and outlet ports; first and second fluid pressure chambers; a metering orifice provided in a discharge passage connected with the outlet port; a pressure regulating section arranged to regulate the pressure introduced into the first or second fluid pressure chamber, and including a high pressure chamber, a middle pressure chamber, and a low pressure chamber; a relief valve; a pilot orifice provided in a passage connecting the metering orifice and the middle pressure chamber, and having a circular section with a diameter of a mm; and a damper orifice provided in a passage connecting the outlet port and the high pressure chamber, and having a circular section with a diameter of b mm. The pilot orifice and the damper orifice satisfy the following relationships: a+2b?2.1?0, ?4a+b?16.3?0, and a?1.8.

Abstract: A variable displacement vane pump that assuredly suppresses seizing of mutually contacting surfaces of a pressure plate and a rotor where the pressure plate is formed, at one side surface thereof that slidably contacts the rotor, with an annular lubricating groove. The lubricating groove is on a seal surface of the side surface at a position between arcuate back pressure grooves formed on the seal surface and a through opening which is formed in a center part of the pressure plate to receive the drive shaft. A radial width of the lubricating groove is set to a range from 10% to 25% of a radial width of the seal surface, and a distance from a center of the radial width of the lubricating groove to an inner cylindrical surface of the through opening is set to a range from 24% to 70% of the radial width of the seal surface.

Abstract: A variable displacement vane pump includes a rotor, a cam ring; and a pump casing including first and second side walls disposed on both sides of the cam ring, and a circumferential wall surrounding the cam ring and defining first and second pressure chambers. A pressure introduction groove is formed in a sliding contact surface between the cam ring and one of the first and second side walls, and arranged so that a pressure lower than an outlet pressure is introduced.

Abstract: A variable displacement vane pump including a relief valve which includes a valve bore, a spherical valve element in the valve bore, a valve seat fixed onto one axial side of the valve bore and having a through hole and an annular seat surface on which the valve element is seated when the relief valve is in a closed position, a coil spring disposed on the other axial side of the valve bore, and a valve element retainer disposed between the valve element and the coil spring, wherein the seat surface is configured such that when the relief valve is in the closed position, a center of the valve element is located offset from a central axis of one winding seating portion of the coil spring which is disposed on an opposite side of the seat surface, in a radial direction of the valve bore.

Abstract: [Task] To provide a variable displacement vane pump that assuredly suppresses seizing of mutually contacting surfaces of a pressure plate and a rotor. [Means for Achieving the Task] In this variable displacement vane pump, pump elements, such as a drive shaft 7, a rotor 8 and a pressure plate 11 are installed in a receiving space 2a of a front body 2, and an open side of the receiving space 2a is closed by a rear body 3. The pressure plate is formed, at one side surface thereof that slidably contacts the rotor, with an annular lubricating groove 44, the lubricating groove 44 being provided on a seal surface 43 of the side surface at a position between each of arcuate back pressure grooves 41 and 42 which are formed on the seal surface 43 and a through opening 26 which is formed in a center part of the pressure plate to receive the drive shaft.

Abstract: A variable displacement pump includes: a pump body; a rotor; a cam ring; inlet and outlet ports; first and second fluid pressure chambers; a metering orifice provided in a discharge passage connected with the outlet port; a pressure regulating section arranged to regulate the pressure introduced into the first or second fluid pressure chamber, and including a high pressure chamber, a middle pressure chamber, and a low pressure chamber; a relief valve; a pilot orifice provided in a passage connecting the metering orifice and the middle pressure chamber, and having a circular section with a diameter of a mm; and a damper orifice provided in a passage connecting the outlet port and the high pressure chamber, and having a circular section with a diameter of b mm. The pilot orifice and the damper orifice satisfy the following relationships: a+2b?2.1?0, ?4a+b?16.3?0, and a?1.8.

Abstract: A power steering system includes first and second communication passages for providing communication between a first oil passage and a second oil passage, a third communication passage for providing communication between the first and second communication passages, a directional control valve disposed in the third communication passage, a first check valve disposed in the first communication passage for allowing flow from the first oil passage to a first connection portion only, a second check valve disposed in the first communication passage for allowing flow from second oil passage to the first connection portion only, a third check valve disposed in the second communication passage for allowing flow from a second connection portion to the first oil passage only, and a fourth check valve disposed in the second communication passage for allowing flow from the second connection portion to the second oil passage only.

Abstract: A power steering apparatus includes a hydraulic power cylinder, a reversible pump including a first outlet connected with a first pressure chamber of the power cylinder through a first fluid passage, and a second outlet connected with a second pressure chamber of the power cylinder through a second fluid passage, and a motor for driving the pump. A controller controls the motor in accordance with a sensed steering force. There is further provided a connection passage connecting the first and second fluid passages together, and a closing valve disposed in the connection passage. The controller sends a first current to a coil of the valve to close the connection passage by moving an armature, to send a second current lower than the first current to the coil after the connection passage is closed, and to deenergize the coil to open the connection passage.

Abstract: A variable displacement vane pump includes a rotor, a cam ring; and a pump casing including first and second side walls disposed on both sides of the cam ring, and a circumferential wall surrounding the cam ring and defining first and second pressure chambers. A pressure introduction groove is formed in a sliding contact surface between the cam ring and one of the first and second side walls, and arranged so that a pressure lower than an outlet pressure is introduced.