대표
청구항
▼
1. A hydraulic pressure control device of a vehicle driving device, the hydraulic pressure control device comprising: a rotary electric machine capable of switching a rotational direction of a driving force to be output between forward and reverse directions;an input coupled to the rotary electric machine;an output coupled to a wheel;an oil pump supplying a hydraulic pressure;an automatic transmission disposed in a power transmission path between the input and the output, the automatic transmission having a plurality of engagement elements engaged or rel...
1. A hydraulic pressure control device of a vehicle driving device, the hydraulic pressure control device comprising: a rotary electric machine capable of switching a rotational direction of a driving force to be output between forward and reverse directions;an input coupled to the rotary electric machine;an output coupled to a wheel;an oil pump supplying a hydraulic pressure;an automatic transmission disposed in a power transmission path between the input and the output, the automatic transmission having a plurality of engagement elements engaged or released by supplying or draining the hydraulic pressure through control of solenoid valves, the automatic transmission forming a first transmission shift stage or a second transmission shift stage slower than the first transmission shift stage by combining the engagement elements to be engaged or released, the automatic transmission disallowing a reverse rotation output of the rotary electric machine at the first transmission shift stage, wherein reverse travel of a vehicle is achieved by reversely rotating the rotary electric machine while forming the second transmission shift stage; anda range switcher having a first signal solenoid valve capable of supplying a first signal pressure and a spool switchable between a first position reached via the first signal pressure and a second position reached via a biasing force of a biasing member, wherein: the range switcher switches the spool to the first position and self-holds the spool when a shift position is present in a forward travel range and a normal mode is entered,the range switcher keeps on self-holding the spool in the first position and supplies the hydraulic pressure to the engagement elements forming the first transmission shift stage when the shift position is present in the forward travel range and an all-off-fail mode in which no solenoid valves are energized is entered,the range switcher switches the spool to the second position when the shift position is present in a reverse travel range and the normal mode is entered, andthe range switcher supplies the hydraulic pressure to the engagement elements forming the second transmission shift stage when the shift position is present in the reverse travel range and the all-off-fail mode is entered. 2. The hydraulic pressure control device of a vehicle driving device according to claim 1, wherein: the automatic transmission includes a first engagement element, a second engagement element, and a third engagement element as the plurality of engagement elements,the first engagement element is engaged with the second engagement element to form the first transmission shift stage and the first engagement element is engaged with the third engagement element to form the second transmission shift stage,the solenoid valves include a first solenoid valve, a second solenoid valve, and a third solenoid valve, the first solenoid valve being capable of engaging or releasing the first engagement element by supplying the hydraulic pressure to or draining the hydraulic pressure from the first engagement element, the first solenoid valve always receiving an original pressure from the oil pump, the second solenoid valve being capable of engaging or releasing the second engagement element by supplying the hydraulic pressure to or draining the hydraulic pressure from the second engagement element, the third solenoid valve being capable of engaging or releasing the third engagement element by supplying the hydraulic pressure to or draining the hydraulic pressure from the third engagement element, the third engagement element always receiving the original pressure,the range switcher has a first switching valve that includes a first spool as the spool, outputs a holding pressure for self-holding the first spool and a first hydraulic pressure when the first spool is present in the first position, and outputs a second hydraulic pressure when the first spool is present in the second position, anda second switching valve that has a second spool switchable between a normal position reached in the normal mode and a fail position reached in the all-off-fail mode and, when the second spool is present in the fail position, supplies one of the first hydraulic pressure, the second hydraulic pressure, and the original pressure to the first engagement element, supplies the first hydraulic pressure to the second engagement element, and supplies the second hydraulic pressure to the third engagement element. 3. The hydraulic pressure control device of a vehicle driving device according to claim 2, wherein the first switching valve supplies, in the first position, the first hydraulic pressure to the solenoid valves other than the first solenoid valve and the third solenoid valve to enable achievement of the transmission shift stages other than the second transmission shift stage. 4. The hydraulic pressure control device of a vehicle driving device according to claim 3, wherein, when the second spool is present in the fail position, the second switching valve supplies the original pressure to a hydraulic servo of the first engagement element by supplying the original pressure to a drain port of the first solenoid valve, supplies the first hydraulic pressure to a hydraulic servo of the second engagement element by supplying the first hydraulic pressure to a drain port of the second solenoid valve, and supplies the second hydraulic pressure to a hydraulic servo of the third engagement element by supplying the second hydraulic pressure to a drain port of the third solenoid valve. 5. The hydraulic pressure control device of a vehicle driving device according to claim 4, wherein the vehicle driving device includes an electric generator and a power distribution mechanism that transfers a driving force of an output shaft of an internal combustion engine while distributing the driving force among a rotary shaft of the electric generator and the input. 6. The hydraulic pressure control device of a vehicle driving device according to claim 5, wherein: the automatic transmission includes: a case,a planetary gear unit having a first rotary element, a second rotary element, a third rotary element, and a fourth rotary element in accordance with an order in which the first to fourth rotary elements are arranged in a velocity diagram,a first clutch as the first engagement element, which is one of the plurality of engagement elements,a second clutch as the second engagement element, which is one of the plurality of engagement elements,a first brake, which is one of the plurality of engagement elements,a second brake as the third engagement element, which is one of the plurality of engagement elements, anda one-way clutch,the second rotary element is coupled to the output,the first clutch is capable of engaging the input with the first rotary element,the second clutch is capable of engaging the input with the third rotary element,the first brake is capable of locking the case with the fourth rotary element,the second brake is capable of locking the case with the third rotary element,the one-way clutch is engaged in a reversed rotational direction of the third rotary element with respect to the case, anda first stage, which is the second transmission shift stage, is achieved by engaging the first clutch with the one-way clutch or the second brake, a second stage is achieved by engaging the first clutch with the first brake, a third stage, which is the first transmission shift stage, is achieved by engaging the first clutch with the second clutch, and a fourth stage is achieved by engaging the second clutch with the first brake. 7. The hydraulic pressure control device of a vehicle driving device according to claim 6, further comprising: a second signal solenoid valve capable of supplying a second signal pressure capable of pushing the spool of the range switcher to the second position. 8. The hydraulic pressure control device of a vehicle driving device according to claim 1, wherein the range switcher is a range switching valve that: switches the spool to the first position and self-holds the spool at the first original pressure supplied from the oil pump when the shift position is present in the forward travel range and the normal mode is entered,keeps on self-holding the spool in the first position at the first original pressure and supplies a second original pressure supplied from the oil pump to the engagement elements forming the first transmission shift stage when the shift position is present in the forward travel range and the all-off-fail mode is entered, andsupplies the second original pressure to the engagement elements forming the second transmission shift stage when the shift position is present in the reverse travel range and the all-off-fail mode is entered. 9. The hydraulic pressure control device of a vehicle driving device according to claim 8, wherein the range switching valve is capable of supplying the hydraulic pressure to hydraulic servos of the engagement elements without passing through the solenoid valves. 10. The hydraulic pressure control device of a vehicle driving device according to claim 9, wherein the range switching valve is capable of supplying the hydraulic pressure to the hydraulic servos of the engagement elements by supplying the hydraulic pressure to drain ports of the solenoid valves. 11. The hydraulic pressure control device of a vehicle driving device according to claim 10, wherein the vehicle driving device includes an electric generator and a power distribution mechanism that transfers a driving force of an output shaft of an internal combustion engine while distributing the driving force among a rotary shaft of the electric generator and the input. 12. The hydraulic pressure control device of a vehicle driving device according to claim 11, wherein: the automatic transmission includes: a case,a planetary gear unit having a first rotary element, a second rotary element, a third rotary element, and a fourth rotary element in accordance with an order in which the first to fourth rotary elements are arranged in a velocity diagram,a first clutch as the first engagement element, which is one of the plurality of engagement elements,a second clutch as the second engagement element, which is one of the plurality of engagement elements,a first brake, which is one of the plurality of engagement elements,a second brake as the third engagement element, which is one of the plurality of engagement elements, anda one-way clutch,the second rotary element is coupled to the output,the first clutch is capable of engaging the input with the first rotary element,the second clutch is capable of engaging the input with the third rotary element,the first brake is capable of locking the case with the fourth rotary element,the second brake is capable of locking the case with the third rotary element,the one-way clutch is engaged in a reversed rotational direction of the third rotary element with respect to the case, anda first stage, which is the second transmission shift stage, is achieved by engaging the first clutch with the one-way clutch or the second brake, a second stage is achieved by engaging the first clutch with the first brake, a third stage, which is the first transmission shift stage, is achieved by engaging the first clutch with the second clutch, and a fourth stage is achieved by engaging the second clutch with the first brake. 13. The hydraulic pressure control device of a vehicle driving device according to claim 12, further comprising: a second signal solenoid valve capable of supplying a second signal pressure capable of pushing the spool of the range switcher to the second position. 14. The hydraulic pressure control device of a vehicle driving device according to claim 1, wherein the vehicle driving device includes an electric generator and a power distribution mechanism that transfers a driving force of an output shaft of an internal combustion engine while distributing the driving force among a rotary shaft of the electric generator and the input. 15. The hydraulic pressure control device of a vehicle driving device according to claim 14, wherein: the automatic transmission includes: a case,a planetary gear unit having a first rotary element, a second rotary element, a third rotary element, and a fourth rotary element in accordance with an order in which the first to fourth rotary elements are arranged in a velocity diagram,a first clutch as the first engagement element, which is one of the plurality of engagement elements,a second clutch as the second engagement element, which is one of the plurality of engagement elements,a first brake, which is one of the plurality of engagement elements,a second brake as the third engagement element, which is one of the plurality of engagement elements, anda one-way clutch,the second rotary element is coupled to the output,the first clutch is capable of engaging the input with the first rotary element,the second clutch is capable of engaging the input with the third rotary element,the first brake is capable of locking the case with the fourth rotary element,the second brake is capable of locking the case with the third rotary element,the one-way clutch is engaged in a reversed rotational direction of the third rotary element with respect to the case, anda first stage, which is the second transmission shift stage, is achieved by engaging the first clutch with the one-way clutch or the second brake, a second stage is achieved by engaging the first clutch with the first brake, a third stage, which is the first transmission shift stage, is achieved by engaging the first clutch with the second clutch, and a fourth stage is achieved by engaging the second clutch with the first brake. 16. The hydraulic pressure control device of a vehicle driving device according to claim 15, further comprising: a second signal solenoid valve capable of supplying a second signal pressure capable of pushing the spool of the range switcher to the second position. 17. The hydraulic pressure control device of a vehicle driving device according to claim 1, wherein: the automatic transmission includes: a case,a planetary gear unit having a first rotary element, a second rotary element, a third rotary element, and a fourth rotary element in accordance with an order in which the first to fourth rotary elements are arranged in a velocity diagram,a first clutch as the first engagement element, which is one of the plurality of engagement elements,a second clutch as the second engagement element, which is one of the plurality of engagement elements,a first brake, which is one of the plurality of engagement elements,a second brake as the third engagement element, which is one of the plurality of engagement elements, anda one-way clutch,the second rotary element is coupled to the output,the first clutch is capable of engaging the input with the first rotary element,the second clutch is capable of engaging the input with the third rotary element,the first brake is capable of locking the case with the fourth rotary element,the second brake is capable of locking the case with the third rotary element,the one-way clutch is engaged in a reversed rotational direction of the third rotary element with respect to the case, anda first stage, which is the second transmission shift stage, is achieved by engaging the first clutch with the one-way clutch or the second brake, a second stage is achieved by engaging the first clutch with the first brake, a third stage, which is the first transmission shift stage, is achieved by engaging the first clutch with the second clutch, and a fourth stage is achieved by engaging the second clutch with the first brake. 18. The hydraulic pressure control device of a vehicle driving device according to claim 17, further comprising: a second signal solenoid valve capable of supplying a second signal pressure capable of pushing the spool of the range switcher to the second position.
