Abstract: Provided is a hydraulic pressure control device. A hydraulic pressure control device includes a solenoid valve configured to supply hydraulic pressure to switch between an engaged state and a released state of a lock-up clutch, and a transmission control device configured to control the solenoid valve. The solenoid valve supplies hydraulic pressure to switch between a parking locked state and a parking released state of a parking lock mechanism, in addition to switching of the lock-up clutch.

Abstract: The lubrication loop 5 includes a first lubrication flow path L4, a release flow path L6, a low pressure fluid discharge valve 13, a return flow path L7, and a discharge flow path L8. In the low pressure fluid discharge valve 13, an accumulator piston 22 is biased to the other end side of a piston housing chamber 21 by a spring 26 when a pressure of the fluid applied to a piston position control chamber 27 is less than a predetermined pressure so that a supply port 24 and a discharge port 25 communicate with each other via a spool groove 32.

Abstract: An actuator in which the abrasion of a piston and a cylinder can be prevented and it is difficult for the smooth movement of the piston to be hindered is provided. The actuator includes a cylinder (51), a piston (52) that moves inside the cylinder (51) according to a supplied fluid pressure, and a detent mechanism (54) that fixes a position of the piston (52) until the fluid pressure exceeds a predetermined value. The detent mechanism (54) includes a first elastic member 54a and a second elastic member 54b which are arranged to face each other with an axis (a) of the piston (52) interposed therebetween and press the piston (52) so as to sandwich the piston (52) therebetween.

Abstract: The disclosure provides a hydraulic circuit without a dedicated to simplify the structure and reduce the cost. The hydraulic circuit includes an oil pump and a main control valve provided in an oil supply circuit which supplies oil discharged from the oil pump. When a line pressure that acts on the main control valve exceeds a first setting value, the main control valve opens to allow the oil to flow to the oil supply circuit. The main control valve is provided with a relief port connected to a suction side of the oil pump. When the line pressure that acts on the main control valve exceeds a second setting value larger than the first setting value, a part of the oil that flows through the oil supply circuit is returned to the suction side of the oil pump from the relief port of the main control valve.

Abstract: An actuator capable of preventing the inside of a cylinder from being scratched is provided. A two-way piston includes a cylinder having an opening, a piston, and a stroke sensor that detects a position of the piston. The stroke sensor includes a stay that extends from a portion exposed from the opening of the piston to the outside of the cylinder, a member to be detected that is attached to the stay, and a sensor that detects a position of the member to be detected. The piston including a fixing hole having a depth smaller than a diameter of the piston in the portion exposed from the opening. The stay is fixed by a bolt that is inserted into the fixing hole.

Abstract: A parking lock apparatus includes a parking gear rotatable together with a rotating body of a transmission. A slider is to be switched between a parking lock position in which a parking pawl is in engagement with the parking gear and a parking release position in which the parking pawl is out of engagement with the parking gear.

Abstract: In a vehicular parking lock device, the parking lock is actuated when a line pressure is supplied to a left end of a hydraulic actuator (25) via a second solenoid valve (32A), or a hydraulic pressure of an accumulator (37, 38) is supplied to the left end of the hydraulic actuator (25) via a third solenoid valve (32B), and the parking lock is released when a line pressure is supplied to a right end of the hydraulic actuator (25) via a first solenoid valve (32C, 32D). The second solenoid valve (32A) and the first solenoid valve (32D) also function as a solenoid valve that supplies the hydraulic pressure to a torque converter (40) and a solenoid valve that supplies the hydraulic pressure to a hydraulic brake (41) for shift change, respectively. Thus, it is possible to decrease the total number of solenoid valves, thereby cutting the number of components of a hydraulic circuit (31).

Abstract: A simple attachment structure with a minimized piece-part count, allowing easy grounding connection of the solenoid valve. The solenoid valve includes a body section with a built-in electromagnetic coil and a shaft-shaped valve section continued coaxially to the body section. An insertion hole for inserting the valve section in the control body is formed to the control body. The control body includes a locking mechanism composed of a locking piece with elasticity connected to a ground terminal of the electromagnetic coil and projecting out from an outer periphery of the body section and a concave portion provided on an upper surface of the control body. By inserting the valve section into the insertion hole, the locking piece elastically engages with the engaged part to lock the solenoid valve, and the solenoid valve is grounded through a contact between the locking piece and the engaged portion.

Abstract: Provided is a hydraulic pressure control device. A hydraulic pressure control device includes a solenoid valve configured to supply hydraulic pressure to switch between an engaged state and a released state of a lock-up clutch, and a transmission control device configured to control the solenoid valve. The solenoid valve supplies hydraulic pressure to switch between a parking locked state and a parking released state of a parking lock mechanism, in addition to switching of the lock-up clutch.

Abstract: An actuator capable of preventing the inside of a cylinder from being scratched is provided. A two-way piston includes a cylinder having an opening, a piston, and a stroke sensor that detects a position of the piston. The stroke sensor includes a stay that extends from a portion exposed from the opening of the piston to the outside of the cylinder, a member to be detected that is attached to the stay, and a sensor that detects a position of the member to be detected. The piston including a fixing hole having a depth smaller than a diameter of the piston in the portion exposed from the opening. The stay is fixed by a bolt that is inserted into the fixing hole.

Abstract: The lubrication loop 5 includes a first lubrication flow path L4, a release flow path L6, a low pressure fluid discharge valve 13, a return flow path L7, and a discharge flow path L8. In the low pressure fluid discharge valve 13, an accumulator piston 22 is biased to the other end side of a piston housing chamber 21 by a spring 26 when a pressure of the fluid applied to a piston position control chamber 27 is less than a predetermined pressure so that a supply port 24 and a discharge port 25 communicate with each other via a spool groove 32.

Abstract: An actuator in which the abrasion of a piston and a cylinder can be prevented and it is difficult for the smooth movement of the piston to be hindered is provided. The actuator includes a cylinder (51), a piston (52) that moves inside the cylinder (51) according to a supplied fluid pressure, and a detent mechanism (54) that fixes a position of the piston (52) until the fluid pressure exceeds a predetermined value. The detent mechanism (54) includes a first elastic member 54a and a second elastic member 54b which are arranged to face each other with an axis (a) of the piston (52) interposed therebetween and press the piston (52) so as to sandwich the piston (52) therebetween.

Abstract: Provided is a simple attachment structure with a minimized piece-part count, allowing easy earth connection of the solenoid valve. The solenoid valve includes a body section with a built-in electromagnetic coil and a shaft-shaped valve section continued coaxially to the body section. An insertion hole for inserting the valve section in the control body is formed to the control body. The control body includes a locking mechanism composed of a locking piece with elasticity connected to a ground terminal of the electromagnetic coil and projecting out from an outer periphery of the body section and a concave portion provided on an upper surface of the control body. By inserting the valve section into the insertion hole, the locking piece elastically engages with the engaged part to lock the solenoid valve, and the solenoid valve is grounded through a contact between the locking piece and the engaged portion.

Abstract: A check valve includes a check valve body and a check valve member. The check valve body includes a check valve outlet port and a check valve oil path. The check valve member is movable in the check valve oil path to move in a first direction in which the check valve member is pushed by hydraulic fluid due to hydraulic pressure from a hydraulic pump. A switching valve includes a switching valve body. The switching valve body includes a switching valve inlet port connected to the check valve outlet port and a receiving surface facing the check valve outlet port. The check valve member contacts the receiving surface after the hydraulic pump starts providing hydraulic pressure. The switching valve body is supported by a valve body via a first O-ring and a second O-ring such that the switching valve body is movable in the first direction.

Abstract: In a vehicular parking lock device, supplying a hydraulic pressure from pressure regulation of a line pressure by a linear solenoid valve to a hydraulic brake via a switching valve operated by a first solenoid valve enables a transmission to carry out a shift change. If desired that a parking lock is not operated when an engine stops, the hydraulic pressure stored under pressure in an accumulator is discharged to a drain oil passage by connecting the linear solenoid valve selectively to the drain oil passage by the first solenoid valve, thereby making it possible to prevent the hydraulic pressure stored under pressure in the accumulator from being supplied to a locking oil chamber at the other end of the hydraulic actuator. The first solenoid valve is used for both controlling the operation of the hydraulic brake and discharge of the hydraulic pressure stored under pressure in the accumulator.

Abstract: A parking lock apparatus includes a parking gear rotatable together with a rotating body of a transmission. A slider is to be switched between a parking lock position in which a parking pawl is in engagement with the parking gear and a parking release position in which the parking pawl is out of engagement with the parking gear. A hydraulic circuit includes a third oil passage through which a first line pressure is applied to push the slider toward the parking release position, a fourth oil passage through which a second line pressure is applied to push the slider toward the parking lock direction, and a hydraulic cut valve provided in the third oil passage to be opened when a difference between the first line pressure and the second line pressure is higher than or equal to a threshold pressure when applying line pressure to the hydraulic circuit is started.

Abstract: In a vehicular parking lock device, supplying a hydraulic pressure from pressure regulation of a line pressure by a linear solenoid valve to a hydraulic brake via a switching valve operated by a first solenoid valve enables a transmission to carry out a shift change. If desired that a parking lock is not operated when an engine stops, the hydraulic pressure stored under pressure in an accumulator is discharged to a drain oil passage by connecting the linear solenoid valve selectively to the drain oil passage by the first solenoid valve, thereby making it possible to prevent the hydraulic pressure stored under pressure in the accumulator from being supplied to a locking oil chamber at the other end of the hydraulic actuator. The first solenoid valve is used for both controlling the operation of the hydraulic brake and discharge of the hydraulic pressure stored under pressure in the accumulator.

Abstract: In a vehicular parking lock device, the parking lock is actuated when a line pressure is supplied to a left end of a hydraulic actuator (25) via a second solenoid valve (32A), or a hydraulic pressure of an accumulator (37, 38) is supplied to the left end of the hydraulic actuator (25) via a third solenoid valve (32B), and the parking lock is released when a line pressure is supplied to a right end of the hydraulic actuator (25) via a first solenoid valve (32C, 32D). The second solenoid valve (32A) and the first solenoid valve (32D) also function as a solenoid valve that supplies the hydraulic pressure to a torque converter (40) and a solenoid valve that supplies the hydraulic pressure to a hydraulic brake (41) for shift change, respectively. Thus, it is possible to decrease the total number of solenoid valves, thereby cutting the number of components of a hydraulic circuit (31).

Abstract: A check valve includes a check valve body and a check valve member. The check valve body includes a check valve outlet port and a check valve oil path. The check valve member is movable in the check valve oil path to move in a first direction in which the check valve member is pushed by hydraulic fluid due to hydraulic pressure from a hydraulic pump. A switching valve includes a switching valve body. The switching valve body includes a switching valve inlet port connected to the check valve outlet port and a receiving surface facing the check valve outlet port. The check valve member contacts the receiving surface after the hydraulic pump starts providing hydraulic pressure. The switching valve body is supported by a valve body via a first O-ring and a second O-ring such that the switching valve body is movable in the first direction.