Hydraulic control system and cooling lubrication flow distribution oil passage for automobile transmission

Abstract

Hydraulic control system and cooling lubrication flow distribution oil circuit for automobile transmission, the technical field of automobile transmission hydraulic control, aiming at the technical bottlenecks such as energy consumption optimization and cooling lubrication flow fine control of the existing automobile transmission hydraulic control system under the double pump cooperative working mode, an integrated and intelligent valve body hydraulic control scheme is proposed, which solves the problems of high load pressure and high energy consumption of the electronic pump working alone in the traditional double pump system, and the defects of fixed cooling lubrication circuit flow distribution and inability to adjust as needed.

Description

Technical Field

[0001] This invention belongs to the field of automotive transmission hydraulic control technology, and in particular to hydraulic control systems and cooling and lubrication flow distribution oil circuits for automotive transmissions. Background Technology

[0002] Existing automotive transmission hydraulic control systems primarily employ a dual-pump oil supply architecture, with both mechanical and electronic pumps working in tandem to meet lubrication, cooling, and pressure control requirements under varying operating conditions. In hybrid and new energy transmissions, the mechanical pump is typically engine-driven, providing the main oil pressure and high flow rate during high-speed vehicle operation. The electronic pump, driven by an independent motor and decoupled from vehicle speed and engine speed, mainly supplements oil supply during low-speed pure electric mode or start-stop conditions. Both pumps are connected in parallel to the main oil circuit via a check valve, enabling flexible switching and redundancy of the oil source. The main pressure regulating valve, as the core pressure regulating element of the system, achieves precise control of the main oil pressure and overflows some excess flow to the cooling and lubrication circuit, ensuring stable system pressure while meeting lubrication and cooling requirements. In terms of cooling and lubrication circuit design, existing technologies generally guide the overflow oil from the main pressure regulating valve and the output oil from the electronic pump to the heat-loaded components such as friction pairs, bearings, clutches, motors, and generators of the transmission. However, the lubrication and cooling oil circuits are mostly controlled by throttle orifices or simple switching valves, which cannot achieve on-demand distribution of cooling flow. This can easily lead to excessively high oil temperatures, resulting in decreased transmission efficiency and component damage.

[0003] Existing technologies still have room for improvement in areas such as the coordinated control precision of mechanical and electronic pumps, suppression of transient fluctuations in main oil pressure, refined distribution of cooling and lubrication flow, and optimization of system energy consumption. In particular, there is an urgent need for more integrated and intelligent hydraulic control solutions in key technologies such as smooth pressure transition during dual-pump switching, decoupling control of cooling oil circuit and main pressure oil circuit, and on-demand flow adjustment. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned problems in existing technologies. Specifically, it proposes an integrated and intelligent valve body hydraulic control scheme to overcome the bottlenecks in energy consumption optimization and refined control of cooling and lubrication flow in existing automotive transmission hydraulic control systems operating under dual-pump collaborative modes. This solution primarily addresses the following key technical issues: First, to address the problem of excessively high load pressure and energy consumption when the electronic pump operates alone in traditional dual-pump systems, this invention optimizes the oil circuit on / off logic of the main pressure regulating valve controlled by the mechanical pump and the electronic pump, reconstructing the oil flow path. This allows the electronic pump to bypass the main pressure regulating valve and directly supply oil for cooling and lubrication in independent oil supply mode, significantly reducing the workload and drive power consumption of the electronic pump and improving energy utilization efficiency in pure electric mode. Second, to address the deficiency of fixed flow distribution in existing cooling and lubrication circuits that cannot be adjusted as needed, this invention adds a control valve to the generator cooling oil circuit channel. This valve can allocate cooling flow as needed based on the working pressure of the mechanical pump, ensuring generator heat dissipation while avoiding over-cooling and oil waste.

[0005] Meanwhile, the optimized collaborative control strategy for mechanical and electronic pumps allows for low-pressure direct lubrication and cooling from the electronic pump in pure electric mode. When both mechanical and electronic pumps are working together, high-pressure control oil is provided through the main pressure regulating valve for overflow cooling, reducing pressure fluctuations and flow shocks during mode switching. The proposed oil circuit architecture, by adjusting the bore parameters of the control valve and the control strategy, can match transmission systems with different power levels and cooling requirements, providing important technical support for the lightweight, efficient, and intelligent development of new energy vehicle transmissions.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] Hydraulic control systems and cooling / lubricating flow distribution circuits for automotive transmissions, including: mechanical pumps, electronic pumps, main pressure regulating valves, control valves, solenoid valves, check valves, oil coolers, main pressure oil circuits, cooling / lubricating oil passages, drain oil circuits, oil pans, oil filters, and clutches.

[0008] The oil outlet of the mechanical pump is fixedly connected to the main pressure regulating valve and the control valve;

[0009] The main pressure regulating valve is fixedly connected to the main pressure oil circuit, the cooling lubrication oil passage, and the drain oil passage, respectively.

[0010] The oil outlet of the electronic pump is fixedly connected to the oil outlet of the main pressure regulating valve through a one-way valve, and the oil inlet of the electronic pump is fixedly connected to the oil drain circuit.

[0011] One end of the control valve is fixedly connected to the cooling and lubricating oil passage, and the other end is fixedly connected to the main pressure oil passage.

[0012] The clutch is fixedly connected to the main pressure oil circuit via a solenoid valve;

[0013] The oil cooler is connected to the cooling lubrication oil passage;

[0014] The lower end of the oil filter is provided with an oil pan, and the upper end of the oil filter is connected to the main pressure oil circuit, the cooling lubrication oil circuit and the drain oil circuit.

[0015] The one-way valve is provided with an oil drain hole.

[0016] The cooling and lubricating oil passage is provided with a throttling orifice assembly, which includes a throttling orifice a, a throttling orifice b, and a throttling orifice c.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] This invention provides a hydraulic control system and cooling / lubrication flow distribution circuit for automotive transmissions. It significantly reduces the load pressure of the electronic pump operating alone, directly providing low-pressure, high-flow-rate oil to the cooling / lubrication circuit, thus reducing noise and vibration. The addition of control valve B allows for on-demand distribution of cooling generator oil flow based on the mechanical pump's operating pressure, minimizing unnecessary oil circulation and reducing system energy consumption while ensuring the generator does not overheat. By optimizing the oil circuit design of the main pressure regulating valve controlling the mechanical and electronic pumps, the response time for hydraulic system pressure regulation and flow distribution is shortened, significantly improving clutch engagement quality and enhancing the overall vehicle power transmission quality and driving experience. Attached Figure Description

[0019] Figure 1 This is the working oil circuit diagram of the electronic pump;

[0020] Figure 2 This is a circuit diagram showing the combined operation of an electronic pump and a mechanical pump. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0022] Combination Figures 1-2 The hydraulic control system and cooling / lubricating flow distribution circuit used in automotive transmissions include: mechanical pump 1, electronic pump 2, main pressure regulating valve 3, control valve 4, solenoid valve 5, check valve 6, oil cooler 7, main pressure oil circuit 8, cooling / lubricating oil passage 9, drain oil circuit 10, oil pan 11, oil filter 12, and clutch 15.

[0023] The outlet of the mechanical pump 1 is fixedly connected to the main pressure regulating valve 3 and the control valve 4, and is used to regulate the main oil pressure of the system and the opening and closing of the control valve 4, which is the main pressure oil circuit 8 in the figure.

[0024] The main pressure regulating valve 3 is fixedly connected to the main pressure oil circuit 8, the cooling and lubrication oil passage 9, and the drain oil passage 10, respectively.

[0025] The oil outlet of the electronic pump 2 is fixedly connected to the oil outlet of the main pressure regulating valve 3 through a one-way valve 6, and the oil inlet of the electronic pump 2 is fixedly connected to the oil drain circuit 10, which can reduce the load pressure of the electronic pump 2 when it is working.

[0026] Furthermore, the oil circuit connecting to the cooling generator adjusts the cooling oil as needed via control valve 4.

[0027] Furthermore, when the electronic pump 2 works alone, the engine, generator, and mechanical pump 1 are not working. The oil only needs to provide lubrication and cooling for the drive motor. The control valve 4 can reduce the amount of oil used to cool the generator, thus reducing waste. When the mechanical pump 1 and the electronic pump 2 work together, the control valve 4 opens when it receives pressure from the mechanical pump 1, increasing the oil path to the generator and achieving a reasonable distribution of the generator oil as needed.

[0028] Furthermore, this invention optimizes the internal flow channel, significantly reducing the workload and drive power consumption of the electronic pump in pure electric mode, and improving energy utilization efficiency.

[0029] One end of the control valve 4 is fixedly connected to the cooling and lubricating oil passage 9, and the other end is fixedly connected to the main pressure oil passage 8.

[0030] The clutch 15 is fixedly connected to the main pressure oil circuit 8 via the solenoid valve 5;

[0031] The oil cooler 7 is connected to the cooling and lubrication oil passage 9;

[0032] The lower end of the oil filter 12 is provided with an oil pan 11, and the upper end of the oil filter 12 is connected to the main pressure oil passage 8, the cooling lubrication oil passage 9 and the drain oil passage 10.

[0033] The one-way valve 6 is provided with an oil drain hole 14.

[0034] The cooling and lubricating oil passage 9 is provided with a throttling orifice assembly 13, which includes a throttling orifice a13-1, a throttling orifice b13-2, and a throttling orifice c13-3.

[0035] Furthermore, the oil circuit design is optimized to reduce the load pressure of the electronic pump:

[0036] The electronic pump 2 is directly connected to the oil outlet of the main pressure regulating valve 3. Compared with the traditional mode of connecting to the oil inlet of the main pressure regulating valve 3, it is not necessary to open the main pressure regulating valve 3, which significantly reduces the load pressure when the electronic pump 2 works alone. It can directly provide low-pressure, high-flow oil to the cooling and lubrication oil passage 9, reducing the operating speed, temperature, noise and vibration of the electronic pump 2, and extending its service life.

[0037] Furthermore, the distribution of cooling and lubrication flow and the design of oil circuits under different operating modes:

[0038] 1. Electronic pump working oil circuit

[0039] Depend on Figure 1 It can be seen that in pure electric drive mode, only the electric motor drives the electronic pump 2 to work alone, and the engine does not work. At this time, the generator and mechanical pump 1 have no working pressure. The oil flows from the electronic pump 2 to the cooling lubrication oil passage 9 through the one-way valve 6. The main pressure regulating valve 3 and the control valve 4 are not under force and remain closed, so the oil passage is not open. Therefore, under the action of the electronic pump 2, the oil flows to the rear end and intermediate shaft for lubrication, and flows through the oil cooler 7 to the cooling lubrication oil passage 9. At this time, since the throttle orifice a13-1 and throttle orifice b13-2 are the same size and much larger than the throttle orifice c13-3, most of the oil flows to the drive motor for cooling, and a very small amount flows to the generator through the oil passage throttle orifice c13-3. When the electronic pump 2 works alone, the cooling lubrication oil passage 9 and the drain oil passage 10 in the hydraulic system are open, while the main pressure oil passage 8 is closed.

[0040] 2. The mechanical pump's working oil circuit allows the electronic pump to be selectively started or stopped according to operating conditions.

[0041] Depend on Figure 2 It can be seen that in direct drive mode, the electronic pump 2 can work together with the mechanical pump 1 to supplement the working oil pressure. The mechanical pump 1 is connected to the control chamber of the main pressure regulating valve 3, the oil inlet of the main pressure regulating valve 3, the control chamber of the solenoid valve 5, and the control valve 4. When working, since the opening pressure of the control valve 4 is less than the opening pressure of the valve core of the main pressure regulating valve 3, the oil circuit to the cooling generator will open first. After reaching the opening pressure of the main pressure regulating valve 3, the oil in the oil circuit will flow into the cooling lubrication oil passage 9. The oil flows to the rear end, the intermediate shaft lubrication, and through the oil cooler 7 to the cooling lubrication oil passage 9. At this time, since the throttle orifice a13-1 and the throttle orifice b13-2 are the same size and much larger than the throttle orifice c13-3, the oil circuit is open. The oil in the cooling lubrication oil passage 9 can be regarded as being evenly distributed to the drive motor and the generator. Most of the oil flowing to the generator is achieved through the throttle orifice a13-1, the control valve 4, and then to the oil circuit, thereby achieving the purpose of distributing the cooling oil on demand. When the electronic pump 2 and the mechanical pump 1 work together, the main pressure oil circuit 8, the cooling and lubrication oil passage 9 and the drain oil passage 10 in the hydraulic system are filled with oil.

[0042] When the electronic pump 2 is not in operation, the one-way valve 6 connected to the electronic pump 2 can prevent oil backflow. At this time, the oil will flow to the cooling lubrication oil passage 9 when the mechanical pump 1 opens the main pressure regulating valve 3.

[0043] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A hydraulic control system and cooling / lubrication flow distribution oil circuit for automotive transmissions, characterized in that: include: Mechanical pump (1), electronic pump (2), main pressure regulating valve (3), control valve (4), solenoid valve (5), check valve (6), oil cooler (7), main pressure oil circuit (8), cooling and lubrication oil passage (9), drain oil circuit (10), oil pan (11), oil filter (12), clutch (15); The outlet of the mechanical pump (1) is fixedly connected to the main pressure regulating valve (3) and the control valve (4); The main pressure regulating valve (3) is fixedly connected to the main pressure oil circuit (8), the cooling lubrication oil circuit (9) and the drain oil circuit (10); The oil outlet of the electronic pump (2) is fixedly connected to the oil outlet of the main pressure regulating valve (3) through a one-way valve (6), and the oil inlet of the electronic pump (2) is fixedly connected to the oil drain circuit (10). One end of the control valve (4) is fixedly connected to the cooling and lubrication oil passage (9), and the other end is fixedly connected to the main pressure oil passage (8); The clutch (15) is fixedly connected to the main pressure oil circuit (8) through the solenoid valve (5); The oil cooler (7) is connected to the cooling lubrication oil passage (9); The lower end of the oil filter (12) is provided with an oil pan (11), and the upper end of the oil filter (12) is connected to the main pressure oil circuit (8), the cooling lubrication oil circuit (9) and the drain oil circuit (10).

2. The hydraulic control system and cooling / lubricating flow distribution oil circuit for an automotive transmission according to claim 1, characterized in that: The one-way valve (6) is provided with an oil drain hole (14).

3. The hydraulic control system and cooling / lubricating flow distribution oil circuit for an automotive transmission according to claim 1, characterized in that: The cooling and lubricating oil passage (9) is provided with a throttling orifice assembly (13), which includes: throttling orifice a (13-1), throttling orifice b (13-2) and throttling orifice c (13-3).

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