Hybrid transmission hydraulic system

Abstract

The present invention discloses a hybrid transmission hydraulic system, comprising a first hydraulic pump, a second hydraulic pump, a cooling oil circuit connected to the first hydraulic pump, a main pressure regulating valve connected to the second hydraulic pump, a generator cooling control valve connected to the main pressure regulating valve, a clutch pressure control oil circuit connected to the second hydraulic pump and used for conveying pressure oil to a clutch, and a switch valve connected to the clutch pressure control oil circuit and the main pressure regulating valve, the clutch pressure control oil circuit being connected to the main pressure regulating valve via a pilot oil circuit, and the switch valve being connected to the control valve pilot oil circuit.

Description

Technical Field

[0001] The present invention belongs to the technical field of transmissions, and in particular, relates to a hybrid transmission hydraulic system. Background Art

[0002] In the prior art, a pressure regulating valve is provided in a hybrid vehicle system to control and adjust the pressure, which has high requirements on the cleanliness of the valve body and the transmission assembly, is more prone to jamming, and has poor reliability. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a hybrid transmission hydraulic system, the purpose of which is to improve reliability.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a hybrid transmission hydraulic system, including a first hydraulic pump, a second hydraulic pump, a cooling oil circuit connected to the first hydraulic pump, a main pressure regulating valve connected to the second hydraulic pump, a generator cooling control valve connected to the main pressure regulating valve, a clutch pressure control oil circuit connected to the second hydraulic pump and used to deliver pressure oil to the clutch, and a switch valve connected to the clutch pressure control oil circuit and the main pressure regulating valve, the clutch pressure control oil circuit is connected to the main pressure regulating valve through a pilot oil circuit, and the switch valve is connected to the control valve pilot oil circuit.

[0005] The clutch pressure control oil circuit includes a clutch pressure control valve, and the clutch pressure control valve is connected to the pilot oil circuit.

[0006] The output end of the switch valve is connected to the spring side of the main pressure regulating valve and the pilot side of the clutch pressure control valve through the pilot oil circuit. When the switch valve is opened, the pressure of the main oil circuit is increased and the valve core of the clutch pressure control valve is pushed to move.

[0007] A first throttle hole is arranged in the pilot oil circuit, and the first throttle hole is located between the switch valve and the clutch pressure control valve.

[0008] A second throttle hole is arranged in the pilot oil circuit, and the second throttle hole is located between the switch valve and the main pressure regulating valve.

[0009] The cooling oil circuit is connected to the clutch and the drive motor, the cooling oil circuit includes a first one-way valve and an oil cooler, and the generator cooling control valve is connected to the oil cooler.

[0010] The cooling oil circuit also includes a cooling pressure control valve, which is connected to the oil tank, the oil cooler and the main pressure regulating valve.

[0011] The clutch pressure control valve is connected to an accumulator, and the accumulator is connected to the clutch.

[0012] The working pressure range of the accumulator is 1-9 Bar, and the initial working pressure of the accumulator is greater than the clutch KP point pressure.

[0013] The first hydraulic pump is connected to the differential, and the second hydraulic pump is connected to the engine output shaft.

[0014] The hybrid transmission hydraulic system of the present invention controls pressure through a switch valve and a series of sliding valves, has higher tolerance to pollutants and higher reliability; and only uses one switch solenoid valve for control to achieve flow and pressure control under various working conditions of a single-speed DHT transmission. It has a compact layout, small space, obvious cost advantages, and reduces occupied space. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] This specification includes the following drawings, which show the following contents:

[0016] Figure 1 is a schematic structural diagram of a hybrid transmission hydraulic system of the present invention;

[0017] Markings in the figure are: 1. First hydraulic pump; 2. Second hydraulic pump; 3. Main pressure regulating valve; 4. Generator cooling control valve; 5. Clutch pressure control valve; 6. Switch valve; 7. Pilot oil circuit; 8. First throttle hole; 9. Second throttle hole; 10. First one-way valve; 11. Second one-way valve; 12. Gear shaft cooling branch; 13. Suction filter; 14. Oil cooler; 15. Accumulator; 16. Pressure sensor; 17. Clutch cooling branch; 18. Drive motor cooling branch; 19. Cooling pressure control valve; 20. Main oil circuit. DETAILED DESCRIPTION

[0018] The specific implementation methods of the present invention are further explained in detail below by describing the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present invention and facilitating its implementation.

[0019] It should be noted that, in the following embodiments, the “first”, “second” and “third” mentioned do not represent an absolute distinction in structure and / or function, nor do they represent a sequence of execution, but are merely for the convenience of description.

[0020] like Figure 1As shown, the present invention provides a hybrid transmission hydraulic system, including a first hydraulic pump 1, a second hydraulic pump 2, a cooling oil circuit connected to the first hydraulic pump 1, a main pressure regulating valve 3 connected to the second hydraulic pump 2, a generator cooling control valve 4 connected to the main pressure regulating valve 3, a clutch pressure control oil circuit connected to the second hydraulic pump 2 and used for conveying pressure oil to the clutch, and a switch valve 6 connected to the clutch pressure control oil circuit and the main pressure regulating valve 3, the clutch pressure control oil circuit is connected to the main pressure regulating valve 3 through a pilot oil circuit 7, the switch valve 6 is connected to the control valve pilot oil circuit 7, and the generator cooling control valve 4 is connected to the cooling oil circuit.

[0021] Specifically, if Figure 1 As shown, the first hydraulic pump 1 and the second hydraulic pump 2 are both mechanical pumps, the switch valve 6 is a solenoid valve, the main pressure regulating valve 3 is a slide valve, and the generator cooling control valve 4 is a pilot slide valve. The clutch pressure control oil circuit includes a clutch pressure control valve 5, which is connected to the pilot oil circuit 7. The clutch pressure control valve 5 is a pilot slide valve, and the clutch pressure control valve 5 has a pilot control port, an oil inlet, and an oil outlet.

[0022] like Figure 1 As shown, the oil inlet of the clutch pressure control valve 5 is connected to the oil outlet of the second hydraulic pump 2 through the main oil circuit, and the oil outlet of the clutch pressure control valve 5 is connected to the clutch of the hybrid transmission through an oil pipe. The input end of the switch valve 6 is connected to the main oil circuit, and the connection point between the switch valve 6 and the main oil circuit is located between the clutch pressure control valve 5 and the second hydraulic pump 2. A pressure sensor 16 is provided on the oil pipe connecting the clutch and the clutch pressure control valve 5, and the pressure sensor 16 is used to monitor the oil pressure.

[0023] Preferably, the first hydraulic pump 1 is connected to a differential on the vehicle, and the differential drives the first hydraulic pump 1 to operate, and the second hydraulic pump 2 is connected to an output shaft of an engine on the vehicle. When the engine is working, it can drive the second hydraulic pump 2 to operate.

[0024] like Figure 1 As shown, the main pressure regulating valve 3 has a first control port, a second control port, an oil inlet and an oil outlet. The first control port and the oil inlet of the main pressure regulating valve 3 are connected to the main oil circuit, the second control port of the main pressure regulating valve 3 is connected to the pilot oil circuit 7, and the oil outlet of the main pressure regulating valve 3 is connected to the cooling oil circuit. The oil inlet of the main pressure regulating valve 3 is located between the first control port and the second control port. After the oil pressure at the first control port reaches the first opening pressure value of the main pressure regulating valve 3, the valve core of the main pressure regulating valve 3 can be pushed to move toward the second control port, and finally the oil inlet and the oil outlet of the main pressure regulating valve 3 are connected, and the oil from the second hydraulic pump 2 can enter the cooling oil circuit through the main pressure regulating valve 3.

[0025] like Figure 1As shown, the output end of the switch valve 6 is connected to the second control port of the main pressure regulating valve 3 and the pilot control port of the clutch pressure control valve 5 through the pilot oil circuit 7. When the switch valve 6 is opened, the pressure of the main oil circuit is increased, and the valve core of the clutch pressure control valve 5 is pushed to move. One end of the pilot oil circuit 7 is connected to the second control port of the main pressure regulating valve 3, and the other end of the pilot oil circuit 7 is connected to the pilot control port of the clutch pressure control valve 5. The output end of the switch valve 6 is connected to the pilot oil circuit 7, and the connection point between the output end of the switch valve 6 and the pilot oil circuit 7 is located between the main pressure regulating valve 3 and the clutch pressure control valve 5. The oil entering the pilot control port of the clutch pressure control valve 5 through the pilot oil circuit 7 can push the valve core of the clutch pressure control valve 5 to move, so that the clutch pressure control valve 5 is opened, the oil inlet and the oil outlet of the clutch pressure control valve 5 are connected, and the oil from the second hydraulic pump 2 can enter the clutch through the clutch pressure control valve 5.

[0026] like Figure 1 As shown, the oil inlet of the clutch pressure control valve 5 is connected to the oil outlet of the second hydraulic pump 2 through the main oil circuit, and the oil outlet of the clutch pressure control valve 5 is connected to the clutch of the hybrid transmission through an oil pipe. The input end of the switch valve 6 is connected to the main oil circuit, and the connection point between the switch valve 6 and the main oil circuit is located between the clutch pressure control valve 5 and the second hydraulic pump 2. A pressure sensor 16 is provided on the oil pipe connecting the clutch and the clutch pressure control valve 5, and the pressure sensor 16 is used to monitor the oil pressure.

[0027] like Figure 1 As shown, the main pressure regulating valve 3 mainly includes a valve body, a movably arranged valve core inside the valve body, and a spring arranged inside the valve body and applying elastic force to the valve core. The valve body is provided with a first control port pl, a second control port s1, an oil inlet and an oil outlet. A valve cavity for accommodating the valve core and the spring is arranged inside the valve body. The first control port and the second control port are located at both ends of the valve cavity. The valve core is located between the first control port and the second control port. The spring is also located at the second control port. The spring is sandwiched between the valve core and the inner wall surface of the valve body. The first control port, the second control port, the oil inlet and the oil outlet are connected to the valve cavity. The area of ​​the first end face of the valve core is greater than the area of ​​the second end face. The valve core is a variable cross-section structure. The first end and the second end of the valve core are opposite ends of the valve core in the axial direction. The first end of the valve core is close to the first control port, and the second end of the valve core is close to the second control port.

[0028] like Figure 1As shown, when the hybrid transmission is in the engine direct drive mode, the clutch needs to be in the engaged state, and the pressure required for the clutch to engage is relatively high. At this time, the switch valve 6 needs to be controlled to open. When the switch valve 6 is opened, oil flows into the second control port of the main pressure regulating valve 3, and the oil pressure at the second control port increases. The oil entering the second control port contacts the second end face of the valve core. The force area of ​​the second end face of the valve core is smaller than the force area of ​​the first end face. The second end of the valve core is acted upon by the spring force and the oil pressure. The pressure at the second end of the valve core increases, and the valve core of the main pressure regulating valve 3 moves toward the first control port to close the main pressure regulating valve 3. Then, as the oil pressure at the first control port of the main pressure regulating valve 3 gradually increases, the valve core of the main pressure regulating valve 3 gradually moves toward the second control port until the oil pressure at the first control port reaches the second opening pressure value of the main pressure regulating valve 3. The main pressure regulating valve 3 is fully opened, and the pressure of the main oil circuit is increased. The pressure of the main oil circuit increases, and the oil in the main oil circuit enters the pilot control port of the clutch pressure control valve 5, pushing the valve core of the clutch pressure control valve 5 to move, so that the clutch pressure control valve 5 is opened, thereby controlling the clutch to complete the corresponding action and engaging the clutch. Then, the hybrid transmission can switch the vehicle to the engine direct drive condition.

[0029] The first opening pressure value of the main pressure regulating valve 3 is less than the second opening pressure value. When the switch valve 6 is closed, the oil pressure in the main oil circuit reaches the first opening pressure value of the main pressure regulating valve 3, and the main pressure regulating valve 3 can be opened. When the switch valve 6 is open, the oil pressure in the main oil circuit must reach the second opening pressure value of the main pressure regulating valve 3 before the main pressure regulating valve 3 can be opened. In this embodiment, the first opening pressure value of the main pressure regulating valve 3 is 2 bar, and the second opening pressure value of the main pressure regulating valve 3 is 7 bar.

[0030] like Figure 1 As shown, a first throttle hole 8 is provided in the pilot oil circuit 7, and the first throttle hole 8 is located between the switch valve 6 and the clutch pressure control valve 5. A second throttle hole 9 is provided in the pilot oil circuit 7, and the second throttle hole 9 is located between the switch valve 6 and the main pressure regulating valve 3. The second throttle hole 9 is closer to the second control port of the main pressure regulating valve 3, and the second throttle hole 9 is farther from the clutch pressure control valve 5. The diameter of the first throttle hole 8 is smaller than the diameter of the second control port, and the diameter of the second throttle hole 9 is smaller than the diameter of the pilot control port of the clutch pressure control valve 5. The diameter of the first throttle hole 8 is 1 mm, and the diameter of the second throttle hole 9 is 1 mm. The cooling flow is distributed through the throttle hole.

[0031] The generator is driven by the engine. When the hybrid transmission is in the extended range mode, the engine starts the generator to run, and the generator provides electrical energy to the drive motor, which drives the vehicle to travel. Figure 1As shown, the generator cooling control valve 4 has a pilot control port, an oil inlet and an oil outlet. The oil inlet of the engine cooling control valve is connected to the cooling oil circuit, and the oil outlet of the engine cooling control valve is connected to the generator. The pilot control port of the generator cooling control valve 4 is connected to the main oil circuit, and the rear end oil circuit of the second hydraulic pump 2 performs pilot control on the generator cooling control valve 4. When the second hydraulic pump 2 is running, the oil enters the pilot control port of the generator cooling control valve 4, so that the generator cooling control valve 4 is opened, the oil inlet and the oil outlet of the generator cooling control valve 4 are connected, and the oil from the cooling oil circuit enters the generator through the generator cooling control valve 4, which can cool the working generator.

[0032] like Figure 1 As shown, the cooling oil circuit is connected to the clutch and the drive motor, and the cooling oil circuit includes a first one-way valve 10 and an oil cooler 14, and the generator cooling control valve 4 is connected to the oil cooler 14. The oil inlet of the first one-way valve 10 is connected to the oil outlet of the first hydraulic pump 1, the oil inlet of the first hydraulic pump 1 is connected to the oil tank, and the oil outlet of the first one-way valve 10 is connected to the oil inlet of the oil cooler 14. The cooling oil circuit also includes a generator cooling branch, a clutch cooling branch 17, a drive motor cooling branch 18 and a gear shaft cooling branch 12. The oil outlet of the oil cooler 14 is connected to the generator cooling branch, the clutch cooling branch 17, the drive motor cooling branch 18 and the gear shaft cooling branch 12. The generator cooling branch is used to guide the oil from the oil cooler 14 to the generator cooling control valve 4, the clutch cooling branch 17 is used to guide the oil from the oil cooler 14 to the clutch, the drive motor cooling branch 18 is used to guide the oil from the oil cooler 14 to the drive motor, and the gear shaft cooling branch 12 is used to guide the oil from the oil cooler 14 to the gear shaft. The oil inlet end of the generator cooling branch is connected to the oil cooler 14, and the oil outlet end of the generator cooling branch is connected to the oil inlet of the generator cooling control valve 4. The oil inlet end of the drive motor cooling branch 18 is connected to the oil cooler 14, and the oil outlet end of the drive motor cooling branch 18 is connected to the drive motor, so that the drive motor can be cooled. The oil inlet end of the clutch cooling branch 17 is connected to the oil cooler 14, and the oil outlet end of the clutch cooling branch 17 is connected to the clutch, so the clutch can be cooled. The oil inlet end of the gear cooling branch 12 is connected to the oil cooler 14, and the oil outlet end of the gear cooling branch 12 is connected to the gear, so the gear can be cooled.

[0033] like Figure 1As shown, the cooling oil circuit also includes a cooling pressure control valve 19, which is connected to the oil tank, the oil cooler 14 and the main pressure regulating valve 3. The opening of the cooling pressure control valve 19 is controlled by pressure to overflow the excess flow. The oil outlet of the main pressure regulating valve 3 is connected to the oil inlet of the oil cooler 14. The generator cooling control valve 4 is a pilot-operated slide valve, and the generator cooling control valve 4 has a pilot control port, an oil inlet and an oil outlet. The pilot control port of the generator cooling control valve 4 is connected to the oil outlet of the main pressure regulating valve 3 and the oil outlet of the first non-return valve 10, the oil inlet of the generator cooling control valve 4 is connected to the oil outlet of the main pressure regulating valve 3 and the oil outlet of the first non-return valve 10, and the oil outlet of the generator cooling control valve 4 is connected to the oil tank.

[0034] like Figure 1 As shown, the clutch pressure control valve 5 is connected to the accumulator 15, and the accumulator 15 is connected to the clutch. The working pressure range of the accumulator 15 is 1-9 Bar, and the initial working pressure of the accumulator 15 is greater than the pressure of the clutch KP point (clutch half-engagement point), which can improve the response speed of the clutch. The accumulator 15 is connected to the oil pipe connecting the clutch and the clutch pressure control valve 5, and the connection point between the accumulator 15 and the oil pipe is located between the clutch and the clutch pressure control valve 5.

[0035] In this embodiment, the hybrid transmission is a single-speed DHT transmission.

[0036] The hybrid transmission hydraulic system of the above structure has the following advantages:

[0037] (1) To achieve cooling and lubrication flow and clutch pressure control in pure electric, series, parallel, engine direct drive and other working conditions, only one switch solenoid valve is needed, with relatively few control components, compact layout, small space, obvious cost advantage, and reduced space occupied by the valve body;

[0038] (2) The output end of the switch solenoid valve is connected to the spring side of the main pressure regulating valve 3 and the pilot side of the clutch pressure valve. When the switch solenoid valve is opened, the main oil circuit pressure is increased and the clutch pressure regulating valve core is pushed to move, thereby completing the clutch action;

[0039] (3) Distribute cooling flow through throttle holes;

[0040] (4) The pressure control valve 19 is opened to control the cooling pressure and overflow the excess flow.

[0041] The present invention is described above by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention; or the above concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. Hybrid transmission hydraulic system, characterized by: It includes a first hydraulic pump, a second hydraulic pump, a cooling oil circuit connected to the first hydraulic pump, a main pressure regulating valve connected to the second hydraulic pump, a generator cooling control valve connected to the main pressure regulating valve, a clutch pressure control oil circuit connected to the second hydraulic pump and used for delivering pressure oil to the clutch, and a switch valve connected to the clutch pressure control oil circuit and the main pressure regulating valve, wherein the clutch pressure control oil circuit is connected to the main pressure regulating valve through a pilot oil circuit, and the switch valve is connected to the control valve pilot oil circuit; The clutch pressure control oil circuit includes a clutch pressure control valve, which is connected to the pilot oil circuit. The clutch pressure control valve is a pilot slide valve, and the clutch pressure control valve has a pilot control port, an oil inlet and an oil outlet. The oil inlet of the clutch pressure control valve is connected to the oil outlet of the second hydraulic pump through the main oil circuit, and the oil outlet of the clutch pressure control valve is connected to the clutch of the hybrid transmission through an oil pipe; the input end of the switch valve is connected to the main oil circuit, and the connection point between the switch valve and the main oil circuit is located between the clutch pressure control valve and the second hydraulic pump; The first hydraulic pump is connected to the differential on the vehicle, and the differential drives the first hydraulic pump to operate. The second hydraulic pump is connected to the output shaft of the engine on the vehicle; when the engine is working, it drives the second hydraulic pump to operate. The main pressure regulating valve has a first control port, a second control port, an oil inlet and an oil outlet. The first control port and the oil inlet of the main pressure regulating valve are connected to the main oil circuit, the second control port of the main pressure regulating valve is connected to the pilot oil circuit, and the oil outlet of the main pressure regulating valve is connected to the cooling oil circuit; the oil inlet of the main pressure regulating valve is located between the first control port and the second control port. After the oil pressure at the first control port reaches the first opening pressure value of the main pressure regulating valve, the valve core of the main pressure regulating valve is pushed to move toward the second control port, and finally the oil inlet and the oil outlet of the main pressure regulating valve are connected, and the oil from the second hydraulic pump enters the cooling oil circuit through the main pressure regulating valve; The output end of the switch valve is connected to the second control port of the main pressure regulating valve and the pilot control port of the clutch pressure control valve through the pilot oil circuit. When the switch valve is opened, the pressure of the main oil circuit is increased, and the valve core of the clutch pressure control valve is pushed to move at the same time; one end of the pilot oil circuit is connected to the second control port of the main pressure regulating valve, and the other end of the pilot oil circuit is connected to the pilot control port of the clutch pressure control valve. The output end of the switch valve is connected to the pilot oil circuit, and the connection point between the output end of the switch valve and the pilot oil circuit is located between the main pressure regulating valve and the clutch pressure control valve; the oil entering the pilot control port of the clutch pressure control valve through the pilot oil circuit pushes the valve core of the clutch pressure control valve to move, so that the clutch pressure control valve is opened, the oil inlet and the oil outlet of the clutch pressure control valve are connected, and the oil from the second hydraulic pump enters the clutch through the clutch pressure control valve; The oil inlet of the clutch pressure control valve is connected to the oil outlet of the second hydraulic pump through the main oil circuit, and the oil outlet of the clutch pressure control valve is connected to the clutch of the hybrid transmission through an oil pipe; the input end of the switch valve is connected to the main oil circuit, and the connection point between the switch valve and the main oil circuit is located between the clutch pressure control valve and the second hydraulic pump.

2. The hybrid transmission hydraulic system according to claim 1, characterized in that: The generator cooling control valve has a pilot control port, an oil inlet and an oil outlet. The oil inlet of the engine cooling control valve is connected to the cooling oil circuit, and the oil outlet of the engine cooling control valve is connected to the generator; the pilot control port of the generator cooling control valve is connected to the main oil circuit, and the rear end oil circuit of the second hydraulic pump performs pilot control on the generator cooling control valve. When the second hydraulic pump is running, oil enters the pilot control port of the generator cooling control valve to open the generator cooling control valve, and the oil inlet and oil outlet of the generator cooling control valve are connected, and the oil from the cooling oil circuit enters the generator through the generator cooling control valve to cool the working generator.

3. The hybrid transmission hydraulic system according to claim 1, characterized in that: The first hydraulic pump and the second hydraulic pump are both mechanical pumps.

4. The hybrid transmission hydraulic system according to claim 1, characterized in that: A first throttle hole is arranged in the pilot oil circuit, and the first throttle hole is located between the switch valve and the clutch pressure control valve.

5. The hybrid transmission hydraulic system according to claim 4, characterized in that: A second throttle hole is arranged in the pilot oil circuit, and the second throttle hole is located between the switch valve and the main pressure regulating valve.

6. The hybrid transmission hydraulic system according to any one of claims 1 to 5, characterized in that: The cooling oil circuit is connected to the clutch and the drive motor, the cooling oil circuit includes a first one-way valve and an oil cooler, and the generator cooling control valve is connected to the oil cooler.

7. The hybrid transmission hydraulic system according to claim 6, characterized in that: The cooling oil circuit also includes a cooling pressure control valve, which is connected to the oil tank, the oil cooler and the main pressure regulating valve.

8. The hybrid transmission hydraulic system according to any one of claims 1 to 5, characterized in that: The clutch pressure control valve is connected to an accumulator, and the accumulator is connected to the clutch.

9. The hybrid transmission hydraulic system according to claim 8, characterized in that: The working pressure range of the accumulator is 1-9 Bar, and the initial working pressure of the accumulator is greater than the clutch KP point pressure.

10. The hybrid transmission hydraulic system according to any one of claims 1 to 5, characterized in that: The switch valve is a solenoid valve, the main pressure regulating valve is a slide valve, and the generator cooling control valve is a pilot-operated slide valve.

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