Abstract: Provided is a linear solenoid valve having at least one notch that opens on an end surface of the land of the spool on the drain chamber side and is formed on an outer peripheral surface of the land. In response to movement of the spool, a state is formed in which the end surface of the land on the drain chamber side is located inside the communication chamber and the output chamber and the drain chamber communicate with each other via the notch and the communication chamber, and a state is formed in which the end surface of the land on the drain chamber side is located inside the output chamber and the output chamber and the drain chamber communicate with each other via the communication chamber.

Abstract: Provided is a linear solenoid valve having at least one notch that opens on an end surface of the land of the spool on the drain chamber side and is formed on an outer peripheral surface of the land. In response to movement of the spool, a state is formed in which the end surface of the land on the drain chamber side is located inside the communication chamber and the output chamber and the drain chamber communicate with each other via the notch and the communication chamber, and a state is formed in which the end surface of the land on the drain chamber side is located inside the output chamber and the output chamber and the drain chamber communicate with each other via the communication chamber.

Abstract: A hydraulic control unit of a vehicle drive system including an automatic transmission, and an oil pump device, includes: a first electromagnetic valve; a second electromagnetic valve; first and second oil passages; a third oil passage; a manual valve operated to connect and disconnect the first and third oil passages and a drain oil passage to and from each other, in response to an operation of a manually operated shifting device by a vehicle operator, such that the first oil passage is connected to the third oil passage when the shifting device is placed in a first operating position, while the first oil passage is connected to the drain oil passage when the shifting device is placed in a second operating position; an accumulator connected to the first oil passage; and a check valve provided in the second oil passage.

Abstract: A lock shaft and a shaft member (a plunger and a permanent magnet) of a magnetic locking device are arranged such that a moving direction thereof is orthogonal to a moving direction of a piston rod of a hydraulic actuator. In a parking lock released state, when the coil is not energized, the lock shaft and the shaft member are locked by an attracting force between the permanent magnet and a flange of a yoke so as not to move back from the piston rod, and, when the coil is energized, the attracting force between the permanent magnet and the flange is canceled, so that the lock shaft and the shaft member are allowed to move back from the piston rod.

Abstract: A hydraulic control unit of a vehicle drive system including an automatic transmission, and an oil pump device, includes: a first electromagnetic valve; a second electromagnetic valve; first and second oil passages; a third oil passage; a manual valve operated to connect and disconnect the first and third oil passages and a drain oil passage to and from each other, in response to an operation of a manually operated shifting device by a vehicle operator, such that the first oil passage is connected to the third oil passage when the shifting device is placed in a first operating position, while the first oil passage is connected to the drain oil passage when the shifting device is placed in a second operating position; an accumulator connected to the first oil passage; and a check valve provided in the second oil passage.

Abstract: In a linear solenoid valve, a coil wound on a bobbin is disposed radially outside a first core and a second core of that configure a part of a core segment, and a cover portion is formed by filling the outer periphery of the coil with a resin material so that the coil and the core segment are integrally molded together. The first core includes a small diameter portion having an outside diameter r2 smaller than an outside diameter r1 of an outer tubular portion that is part of the second core and that is opposed to the coil, and a large diameter portion that has an outside diameter r3 larger than that of the small diameter portion. A space between the small diameter portion and the bobbin makes it less likely that the first core is pressed radially inward via the bobbin during formation of the cover portion.

Abstract: A detent lever 20 and a piston rod 42 are engaged with each other through engagement between a recessed portion 26 of the detent lever 20 and a pin portion 52 of a retainer member 50 attached to the piston rod 42. With this configuration, the detent lever 20 and the piston rod 42 can be engaged with each other easily and in a short time when assembling a parking device 10. As a result, the time required for the work of assembling the parking device 10 can be shortened.

Abstract: A magnetic lock device includes a lock shaft having an abutting portion capable of abutting against a roller of a piston rod of a hydraulic pressure actuator, a transfer shaft configured separately from the lock shaft, the transfer shaft abutting against an end surface of the lock shaft, and a magnetic portion locking (restricting movement to the right side in the drawing) the lock shaft, the transfer shaft, and a plunger by attracting the plunger toward an attracting portion using a magnetic force. The lock shaft is surface-hardened to have a higher hardness and the transfer shaft is made of non-magnetic material.

Abstract: In a linear solenoid valve, a coil wound on a bobbin is disposed radially outside a first core and a second core of that configure a part of a core segment, and a cover portion is formed by filling the outer periphery of the coil with a resin material so that the coil and the core segment are integrally molded together. The first core includes a small diameter portion having an outside diameter r2 smaller than an outside diameter r1 of an outer tubular portion that is part of the second core and that is opposed to the coil, and a large diameter portion that has an outside diameter r3 larger than that of the small diameter portion. A space between the small diameter portion and the bobbin makes it less likely that the first core is pressed radially inward via the bobbin during formation of the cover portion.

Abstract: A device includes a switching valve that performs switching between a first state of supplying a line pressure to an oil chamber defined by a case and a piston and a second state of discharging (draining) hydraulic oil in the oil chamber. The device also includes a drain check valve that closes (prohibits the hydraulic oil in the oil chamber from being discharged) when the line pressure is supplied to the oil chamber, and opens (allows the hydraulic oil in the oil chamber to be discharged) when the line pressure is not supplied to the oil chamber. The hydraulic oil is discharged from the oil chamber through the switching valve and the drain check valve.

Abstract: A detent lever 20 and a piston rod 42 are engaged with each other through engagement between a recessed portion 26 of the detent lever 20 and a pin portion 52 of a retainer member 50 attached to the piston rod 42. With this configuration, the detent lever 20 and the piston rod 42 can be engaged with each other easily and in a short time when assembling a parking device 10. As a result, the time required for the work of assembling the parking device 10 can be shortened.

Abstract: A plate spring is attached to the distal-end portion of a piston. The distance L1 between the distal-end portion of a plunger and a core (recessed portion) that faces the distal-end portion of the plunger is set to be shorter than the distance L2 between the distal-end portion (plate spring) of the piston and the projecting end surface of a valve main body that faces the distal-end portion of the piston with drive of a solenoid portion stopped. Consequently, when the solenoid portion is driven, the plate spring collides against the projecting end surface of the valve main body so that the plunger does not collide against the core. As a result, a shock applied to the piston can be absorbed by the elastic force of the plate spring, which suppresses generation of a sound of collision.

Abstract: When an oil temperature Toil is equal to or lower than a threshold Toref, and when a vehicle is predicted to stop while traveling (a shift position is predicted to be operated to a parking position), restricted discharge processing is executed in which a magnetic lock device is turned ON and an on-off solenoid valve is turned OFF. Thus, discharge of hydraulic oil in an oil chamber is started while movement of a piston rod is restricted by the magnetic lock device. Then, when the vehicle stops and the shift position is changed to a parking position, the restriction on the movement of the piston rod is removed by turning OFF the magnetic lock device.

Abstract: A magnetic lock device includes a lock shaft having an abutting portion capable of abutting against a roller of a piston rod of a hydraulic pressure actuator, a transfer shaft configured separately from the lock shaft, the transfer shaft abutting against an end surface of the lock shaft, and a magnetic portion locking (restricting movement to the right side in the drawing) the lock shaft, the transfer shaft, and a plunger by attracting the plunger toward an attracting portion using a magnetic force. The lock shaft is surface-hardened to have a higher hardness and the transfer shaft is made of non-magnetic material.

Abstract: When an oil temperature Toil is equal to or lower than a threshold Toref, and when a vehicle is predicted to stop while traveling (a shift position is predicted to be operated to a parking position), restricted discharge processing is executed in which a magnetic lock device is turned ON and an on-off solenoid valve is turned OFF. Thus, discharge of hydraulic oil in an oil chamber is started while movement of a piston rod is restricted by the magnetic lock device. Then, when the vehicle stops and the shift position is changed to a parking position, the restriction on the movement of the piston rod is removed by turning OFF the magnetic lock device.

Abstract: An electromagnetic pump including a piston, an electromagnetic portion that moves the piston forward, and a spring that moves the piston backward. The piston including a discharge check valve built in the piston. The piston is formed with a hollow portion that opens in an inner peripheral portion of an end surface of the piston, and a spring receiving surface formed on an outer peripheral portion of the end surface to receive the spring. The discharge check valve is fixed through plastic deformation of the piston by inserting the discharge check valve into the hollow portion from an opening of the piston, and partially pressing a portion of the spring receiving surface of the piston on an inner peripheral side after the insertion to recess the spring receiving surface and elevate an inner peripheral surface of the piston surrounding the hollow portion.

Abstract: A device includes a switching valve that performs switching between a first state of supplying a line pressure to an oil chamber defined by a case and a piston and a second state of discharging (draining) hydraulic oil in the oil chamber. The device also includes a drain check valve that closes (prohibits the hydraulic oil in the oil chamber from being discharged) when the line pressure is supplied to the oil chamber, and opens (allows the hydraulic oil in the oil chamber to be discharged) when the line pressure is not supplied to the oil chamber. The hydraulic oil is discharged from the oil chamber through the switching valve and the drain check valve.

Abstract: A lock shaft and a shaft member (a plunger and a permanent magnet) of a magnetic locking device are arranged such that a moving direction thereof is orthogonal to a moving direction of a piston rod of a hydraulic actuator. In a parking lock released state, when the coil is not energized, the lock shaft and the shaft member are locked by an attracting force between the permanent magnet and a flange of a yoke so as not to move back from the piston rod, and, when the coil is energized, the attracting force between the permanent magnet and the flange is canceled, so that the lock shaft and the shaft member are allowed to move back from the piston rod.

Abstract: A plate spring is attached to the distal-end portion of a piston. The distance L1 between the distal-end portion of a plunger and a core (recessed portion) that faces the distal-end portion of the plunger is set to be shorter than the distance L2 between the distal-end portion (plate spring) of the piston and the projecting end surface of a valve main body that faces the distal-end portion of the piston with drive of a solenoid portion stopped. Consequently, when the solenoid portion is driven, the plate spring collides against the projecting end surface of the valve main body so that the plunger does not collide against the core. As a result, a shock applied to the piston can be absorbed by the elastic force of the plate spring, which suppresses generation of a sound of collision.

Abstract: An electromagnetic pump including a reciprocating piston in a cylinder; an electromagnetic portion that moves the piston forward; a first biasing member that moves the piston backward; a support member that supports the first biasing member and defines a pump chamber together with the cylinder and the piston; an intake valve that is incorporated into the support member, is connected to an intake port and prohibits hydraulic fluid from moving in reverse; and a discharge valve that is connected to a discharge port and prohibits the hydraulic fluid from moving in reverse. The intake valve includes a ball, an opening portion of the intake port, and a second biasing member that presses the ball against the opening portion from a side opposite to a direction in which the hydraulic fluid moves. In the opening member, an inner peripheral surface that receives the ball is formed in a taper shape.