Range switching device

A range switching device for switching supply and non-supply of a source pressure based on a hydraulic pressure from a hydraulic pressure generating source to a parking device, the parking device being switched into a parking release state while the source pressure is supplied thereto and being switched into a parking state while the source pressure is not supplied thereto, the range switching device comprising:

• a solenoid valve that pressure-regulates the source pressure to output a control pressure;
• and
• a parking switching valve, wherein:
• the parking switching valve includes
• a first spool that is movable to a first position and to a second position,
• a biasing member that is disposed on one end side of the first spool and biases the first spool to the first position,
• a second spool that is movable to a third position and to a fourth position,
• a first input port to which the source pressure is supplied,
• a first output port that is blocked from communication with the first input port while the first spool is in the first position and is in communication with the first input port while the first spool is in the second position,
• a second input port that is in communication with the first output port,
• a second output port that is in communication with the parking device, is in communication with the second input port while the second spool is in the third position, and is blocked from communication with the second input port while the second spool is in the fourth position,
• a third input port that is in communication with the first output port to receive input of the source pressure so that the second spool is biased to a direction of the fourth position by the source pressure, and
• a control port to which the control pressure is input so as to apply the control pressure output from the solenoid valve to other end side of the first spool and one end side of the second spool,
• in a case in which the control pressure is input to the control port and is applied to the other end side of the first spool and the one end side of the second spool, the first spool is moved to reach the second position against biasing force of the biasing member and the second spool is moved to reach the third position, so that the source pressure is supplied to the parking device through the second output port, and
• in a case in which the control pressure is not input to the control port and the first spool sticks in the second position, the second spool is moved to reach the fourth position by the source pressure supplied to the third input port, so that the source pressure is not supplied to the parking device.