Hydraulic system of a hybrid transmission

Abstract

The present invention discloses a hybrid transmission hydraulic system, including a high-pressure oil circuit, a low-pressure oil circuit, a first oil circuit and a second oil circuit, one end of the high-pressure oil circuit is connected to the oil tank, the other end of the high-pressure oil circuit is respectively connected to one end of the first oil circuit and one end of the second oil circuit, the other end of the first oil circuit is connected to the clutch oil cylinder, the other end of the second oil circuit is connected to the low-pressure oil circuit, one end of the low-pressure oil circuit is connected to the oil tank, and the other end is used to connect various heating parts of the motor, a high-pressure oil pump is arranged on the high-pressure oil circuit, a low-pressure oil pump is arranged on the low-pressure oil circuit, a clutch solenoid valve is arranged on the first oil circuit, and a first overflow valve as a system valve is arranged on the second oil circuit. The hybrid transmission hydraulic system aims to solve the technical problems in the prior art that the hybrid transmission hydraulic system is difficult to meet the pressure requirements of the wet clutch and the flow requirements of the motor heat dissipation under various working conditions and has large hydraulic loss.

Description

Technical Field

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

[0002] With the continuous advancement of new energy vehicles, the market demand for hybrid systems, as a form of new energy vehicles, has also been rising year by year.

[0003] There are many layout forms in the design of hybrid power system. Hydraulic control wet clutch is a more mature form. It can meet multiple driving conditions such as pure electric driving, series driving, high-speed engine direct drive, parallel driving, etc., so that both the motor and the engine drive elements are in an efficient working state, and finally achieve the purpose of low fuel consumption, low emissions, and high mileage. It has good power and economy, and the cost is relatively low. There are also many forms of motor cooling. Among them, oil cooling is a form with better cooling effect and control ability. It can meet the heat dissipation requirements of different parts of the motor under various working conditions, so that the motor temperature is always controlled within a reliable and stable range, providing motor stability and durability. Therefore, the hybrid transmission hydraulic system with clutch control and motor oil cooling is also a sub-part urgently needed by the current hybrid market.

[0004] The main defects of the hybrid transmission hydraulic system in the prior art are that it is difficult to meet the pressure requirements of the wet clutch and the flow requirements of the motor heat dissipation under various working conditions, and the hydraulic loss is large. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] Based on this, the present invention proposes a hybrid transmission hydraulic system, which aims to solve the technical problems in the prior art that the hybrid transmission hydraulic system is difficult to meet the pressure requirements of the wet clutch and the flow requirements of motor heat dissipation under various working conditions and has large hydraulic losses.

[0007] (II) Technical solution

[0008] In order to solve the above technical problems, the present invention proposes a hybrid transmission hydraulic system, which includes a high-pressure oil circuit, a low-pressure oil circuit, a first oil circuit and a second oil circuit. One end of the high-pressure oil circuit is connected to the oil tank, and the other end of the high-pressure oil circuit is respectively connected to one end of the first oil circuit and one end of the second oil circuit. The other end of the first oil circuit is connected to the clutch cylinder, and the other end of the second oil circuit is connected to the low-pressure oil circuit. One end of the low-pressure oil circuit is connected to the oil tank, and the other end of the low-pressure oil circuit is used to connect various heating parts of the motor. A high-pressure oil pump is provided on the high-pressure oil circuit, and a low-pressure oil pump is provided on the low-pressure oil circuit. A clutch solenoid valve is provided on the first oil circuit, and a first overflow valve as a system valve is provided on the second oil circuit. The inlet of the first overflow valve leads to the high-pressure oil circuit, and the outlet of the first overflow valve leads to the low-pressure oil circuit. The oil section of the first oil circuit between the clutch cylinder and the clutch solenoid valve is connected to the spring chamber of the first overflow valve through a third oil circuit, and the control oil circuit of the first overflow valve is connected to the high-pressure oil circuit through the second oil circuit.

[0009] Preferably, the hybrid transmission hydraulic system also includes a first safety oil circuit, one end of the first safety oil circuit is connected to the oil section of the high-pressure oil circuit located between the high-pressure oil pump and the first oil circuit, the other end of the first safety oil circuit is connected to the oil tank, and a second overflow valve serving as a safety valve is provided in the first safety oil circuit.

[0010] Preferably, the hybrid transmission hydraulic system also includes a second safety oil circuit, one end of the second safety oil circuit is connected to the oil circuit section of the second oil circuit located between the first overflow valve and the low-pressure oil circuit, the other end of the second safety oil circuit is connected to the oil tank, and a third overflow valve serving as a safety valve is provided on the second safety oil circuit.

[0011] Preferably, a first pressure sensor is provided on the high-pressure oil circuit. Preferably, a second pressure sensor is provided on the third oil circuit.

[0012] Preferably, an accumulator is connected to one end of the third oil circuit away from the first overflow valve. Preferably, an oil circuit with a reversing steel ball is also connected in parallel to the high-pressure oil circuit.

[0013] Preferably, the low-pressure oil circuit is provided with a one-way valve, a heat exchanger, a bowl-shaped plug and a damping hole in sequence on the oil circuit sections located at the low-pressure oil pump and the various heating parts of the motor.

[0014] Preferably, the high-pressure oil circuit and the low-pressure oil circuit share an oil suction filter.

[0015] (III) Beneficial effects

[0016] Compared with the prior art, the hybrid power transmission hydraulic system of the present invention has the following beneficial effects:

[0017] The dual oil pumps (high-pressure oil pump and low-pressure oil pump) are set up to meet the pressure requirements of the wet clutch and the flow requirements of motor heat dissipation under various working conditions; the system valve (first relief valve) is set up to make the system pressure always slightly higher than the clutch pressure, reducing hydraulic loss, while providing excess flow to motor cooling and reducing the opening time of the low-pressure oil pump; the safety valve is set up to ensure that the pressure of each line always operates within a safe range;

[0018] In the preferred solution, the dynamic control of the wet clutch is met by the arrangement of the clutch solenoid valve, accumulator and pressure sensor; the reasonable distribution of the cooling oil is met by the arrangement of the bowl-shaped plug, the oil pipe with holes, etc.

[0019] This solution is fully functional, has excellent performance, and is characterized by high reliability, high economy, high versatility, low cost, and low energy consumption. It is more mature than the hybrid hydraulic system in existing technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0021] FIG1 is a schematic diagram of the principle of a hybrid transmission hydraulic system according to an embodiment of the present invention.

[0022] 1- high-pressure oil circuit, 2- low-pressure oil circuit, 3- first oil circuit, 4- second oil circuit, 5- oil tank, 6- clutch cylinder, 7- heating part, 8- high-pressure oil pump, 9- low-pressure oil pump, 10- clutch solenoid valve, 11- first overflow valve, 12- third oil circuit, 13- control oil circuit, 14- first safety oil circuit, 15- second overflow valve, 16- second safety oil circuit, 17- third overflow valve, 18- first pressure sensor, 19- second pressure sensor, 20- accumulator, 21- reverse steel ball, 22- one-way valve, 23- heat exchanger, 24- bowl-shaped plug and damping hole, 25- oil suction filter. DETAILED DESCRIPTION

[0023] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0024] However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium, the internal connection of two elements, or a "transmission connection", that is, a power connection through various appropriate methods such as belt drive, gear drive or sprocket drive. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] Referring to FIG1 , the present invention provides a hybrid transmission hydraulic system, which includes a high-pressure oil circuit 1, a low-pressure oil circuit 2, a first oil circuit 3 and a second oil circuit 4. One end of the high-pressure oil circuit 1 is connected to an oil tank 5, and the other end of the high-pressure oil circuit 1 is respectively connected to one end of the first oil circuit 3 and one end of the second oil circuit 4. The other end of the first oil circuit 3 is connected to a clutch cylinder 6, and the other end of the second oil circuit 4 is connected to the low-pressure oil circuit 2. One end of the low-pressure oil circuit 2 is connected to the oil tank 5, and the other end of the low-pressure oil circuit 2 is used to connect various heating parts 7 of the motor. A high-pressure oil pump 8 is provided on the high-pressure oil circuit 1, and a low-pressure oil pump 9 is provided on the low-pressure oil circuit 2. A clutch solenoid valve 10 is provided on the first oil circuit 3, and a first overflow valve 11 as a system valve is provided on the second oil circuit 4. The inlet of the first overflow valve 11 leads to the high-pressure oil circuit 1, and the outlet of the first overflow valve 11 leads to the low-pressure oil circuit 2. The first oil circuit 3 is located at the clutch cylinder 6. The oil circuit section between the clutch solenoid valve 10 is connected to the spring chamber of the first relief valve 11 through the third oil circuit 12. Because the control oil circuit 13 of the first relief valve 11 is connected to the high-pressure oil circuit 1 through the second oil circuit 4, and the control oil circuit 13 is connected to the control chamber of the first relief valve 11, the sum of the pressure of the third oil circuit 12 and the spring pressure in the spring chamber reaches a dynamic balance with the control chamber pressure of the first relief valve 11, so the system pressure is always slightly higher than the clutch pressure.

[0027] According to a specific embodiment of the present invention, the hybrid transmission hydraulic system also includes a first safety oil circuit 14, one end of the first safety oil circuit 14 is connected to the oil circuit section of the high-pressure oil circuit 1 located between the high-pressure oil pump 8 and the first oil circuit 3, and the other end of the first safety oil circuit 14 is connected to the oil tank 5. A second overflow valve 15 serving as a safety valve is provided on the first safety oil circuit 14.

[0028] The hybrid transmission hydraulic system also includes a second safety oil circuit 16, one end of the second safety oil circuit 16 is connected to the oil section of the second oil circuit 4 located between the first overflow valve 11 and the low-pressure oil circuit 2, and the other end of the second safety oil circuit 16 is connected to the oil tank 5. The second safety oil circuit 16 is provided with a third overflow valve 17 as a secondary safety valve.

[0029] In addition, a first pressure sensor 18 is provided on the high-pressure oil circuit 1. A second pressure sensor 19 is provided on the third oil circuit 12. An accumulator 20 is connected to the end of the third oil circuit 12 away from the first overflow valve 11. The high-pressure oil circuit 1 is also connected in parallel with an oil circuit in which a reversing steel ball 21 is provided. A one-way valve 22, a heat exchanger 23, a bowl-shaped plug and a damping hole 24 are sequentially provided on the oil circuit section of the low-pressure oil pump 9 and each heating part 7 of the motor.

[0030] It is necessary to add and emphasize:

[0031] In this solution, the high-pressure oil circuit 1 and the low-pressure oil circuit 2 share an oil suction filter 25, and the present invention is not limited thereto. The high-pressure oil pump 8 is driven by a mechanical component to supply high-pressure oil to the hydraulic valve body to achieve the higher pressure demand of the clutch and the motor cooling oil demand. The low-pressure oil pump 9 is driven by an independent motor to supply low-pressure oil to the motor cooling module to supplement the motor cooling oil.

[0032] In this solution, the first overflow valve 11 as a system valve can dynamically maintain the system pressure slightly higher than the clutch pressure according to the required pressure value of the clutch, and provide high-pressure oil to the clutch solenoid valve 10. The clutch solenoid valve 10 dynamically controls the clutch pressure. At the same time, the system valve overflows the excess flow after meeting the system pressure to the oil-water heat exchanger 23.

[0033] In this solution, the bowl-shaped plug and the perforated oil pipe are both cooling oil distribution mechanisms, which can accurately and reasonably distribute the cooled oil to various heat-generating structures such as motors and bearings to achieve corresponding cooling through simulation calculations and experimental verification.

[0034] In this solution, the second relief valve 15 as a safety valve is used to prevent the system pressure from being too high under specific working conditions and causing failures. The third relief valve 17 as a secondary safety valve is used to prevent the motor cooling pressure from being too high under specific working conditions and causing failures. The pressure sensor is used to collect pressure in real time to facilitate the software system to determine the failure mode.

[0035] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A hybrid transmission hydraulic system, characterized in that: The hybrid transmission hydraulic system comprises a high-pressure oil circuit, a low-pressure oil circuit, a first oil circuit and a second oil circuit, one end of the high-pressure oil circuit is connected to the oil tank, the other end of the high-pressure oil circuit is respectively connected to one end of the first oil circuit and one end of the second oil circuit, the other end of the first oil circuit is connected to the clutch oil cylinder, the other end of the second oil circuit is connected to the low-pressure oil circuit, one end of the low-pressure oil circuit is connected to the oil tank, and the other end of the low-pressure oil circuit is used to connect various heating parts of the motor, a high-pressure oil pump is provided on the high-pressure oil circuit, a low-pressure oil pump is provided on the low-pressure oil circuit, a clutch solenoid valve is provided on the first oil circuit, and a first overflow valve as a system valve is provided on the second oil circuit, the inlet of the first overflow valve leads to the high-pressure oil circuit, and the outlet of the first overflow valve leads to the low-pressure oil circuit, the oil section of the first oil circuit between the clutch oil cylinder and the clutch solenoid valve is connected to the spring chamber of the first overflow valve through the third oil circuit, and the control oil circuit of the first overflow valve is connected to the high-pressure oil circuit through the second oil circuit; The hybrid transmission hydraulic system further comprises a first safety oil circuit, one end of the first safety oil circuit is connected to an oil circuit section of the high-pressure oil circuit between the high-pressure oil pump and the first oil circuit, the other end of the first safety oil circuit is connected to the oil tank, and a second overflow valve as a safety valve is provided on the first safety oil circuit; The high-pressure oil circuit is provided with a first pressure sensor.

2. The hybrid transmission hydraulic system according to claim 1, characterized in that: The hybrid transmission hydraulic system also includes a second safety oil circuit, one end of which is connected to the oil circuit section of the second oil circuit located between the first overflow valve and the low-pressure oil circuit, and the other end of the second safety oil circuit is connected to the oil tank. A third overflow valve serving as a safety valve is provided on the second safety oil circuit.

3. The hybrid transmission hydraulic system according to claim 1, characterized in that: The third oil circuit is provided with a second pressure sensor.

4. The hybrid transmission hydraulic system according to claim 1, characterized in that: An accumulator is connected to one end of the third oil circuit away from the first overflow valve.

5. The hybrid transmission hydraulic system according to any one of claims 1 to 4, characterized in that: The high-pressure oil circuit is also connected in parallel with an oil circuit in which a reversing steel ball is arranged.

6. The hybrid transmission hydraulic system according to any one of claims 1 to 4, characterized in that: The low-pressure oil circuit is located at the oil circuit sections of the low-pressure oil pump and the various heating parts of the motor and is provided with a one-way valve, a heat exchanger, a bowl-shaped plug and a damping hole in sequence.

7. The hybrid transmission hydraulic system according to any one of claims 1 to 4, characterized in that: The high-pressure oil circuit and the low-pressure oil circuit share an oil suction filter.

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