A gearbox hydraulic control system

Abstract

This utility model discloses a hydraulic control system for a transmission, comprising a working oil pump, a lubricating oil pump, and electro-hydraulic proportional directional valves SA, SC, S2, SF, SD, and SE arranged in parallel. This utility model employs a structure where each gear clutch is individually controlled by a proportional valve. Through precise hydraulic actuation and electronic coordination, it achieves breakthroughs in efficiency, smoothness, and reliability of multi-gear transmissions. Its core advantage lies in its modular design to address complex operating conditions, making it particularly suitable for optimizing high-performance, multi-functional engineering vehicle transmission systems.

Description

Technical Field

[0001] This utility model relates to the technical field of hydraulic control equipment for gearboxes, and in particular to a hydraulic control system for gearboxes. Background Technology

[0002] To adapt to complex and diverse working conditions and optimize performance, efficiency, and mechanical lifespan, construction machinery transmissions employ multi-gear control. Lower gears provide greater traction, ensuring mechanical stability during heavy-duty operations. Higher gears increase travel speed, saving time and improving fuel economy during unloaded and relocation operations. However, they suffer from lower shifting efficiency and less smoothness.

[0003] Referring to Korean Patent Publication No. KR970045989A, entitled "Hydraulic Clutch Hydraulic Control Device," this device selectively injects pressurized oil pumped from a pump into the clutch piston via a selector valve to operate the clutch. A portion of the pressurized oil pumped from the pump is introduced into the operating part of the hydraulic clutch through a regulating valve and lubrication lines to lubricate the hydraulic clutch. The hydraulic clutch oil pressure control device consists of interconnected structures. During operation, it controls the working pressure of the clutch by supplying the temperature of the working pressure oil supplied to the clutch to the regulating valve. A temperature compensator is integrally installed to control the working pressure. In this control device, both clutches are regulated and shifted through a single regulating valve. This results in a delayed clutch action during shifting, low shifting efficiency, and poor smoothness. Utility Model Content

[0004] To address the aforementioned technical problems, the purpose of this utility model is to provide a gearbox hydraulic control system that controls each clutch through an independent hydraulic circuit, enabling precise adjustment of engagement / disengagement timing, reducing clutch action delay, and improving shifting efficiency.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A hydraulic control system for a transmission, used to supply oil to a first clutch, a second clutch, a third clutch, a fourth clutch, a fifth clutch, and a sixth clutch within a multi-gear transmission, includes a working oil pump, a lubricating oil pump, and electro-hydraulic proportional directional valves SA, SC, S2, SF, SD, and SE arranged in parallel. The lubricating oil pump provides lubrication to the transmission. The first clutch is connected to the output port of the electro-hydraulic proportional directional valve SA, the input port of the electro-hydraulic proportional directional valve SA is connected to the output end of the working oil pump, and the third clutch is connected to the input port of the electro-hydraulic proportional directional valve SC. The input port of the electro-hydraulic proportional directional valve SC is connected to the output end of the working oil pump. The second clutch is connected to the output port of the electro-hydraulic proportional directional valve S2, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump. The fourth clutch is connected to the input port of the electro-hydraulic proportional directional valve SF, and the input port of the electro-hydraulic proportional directional valve SF is connected to the output end of the working oil pump. The fifth clutch is connected to the output port of the electro-hydraulic proportional directional valve SD, and the input port of the electro-hydraulic proportional directional valve SD is connected to the output end of the working oil pump. The sixth clutch is connected to the output port of the electro-hydraulic proportional directional valve SE, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump.

[0007] In some embodiments, the output end of the working oil pump is also connected to one end of a pressure regulating valve, the other end of the pressure regulating valve is connected to one end of a safety valve, and the other end of the safety valve is connected to a hydraulic torque converter.

[0008] In some embodiments, the working oil pump is connected to an external oil filter A, and the output end of the lubricating oil pump is connected to an external oil filter B, which is connected to the gearbox lubrication inlet.

[0009] In some embodiments, the gearbox lubrication inlet is connected to one end of the cooler, the other end of the cooler is connected to one end of the back pressure valve, and the other end of the back pressure valve is connected to the hydraulic torque converter.

[0010] In some embodiments, a first accumulator is provided between the first clutch and the electro-hydraulic proportional directional valve SA, a second accumulator is provided between the third clutch and the electro-hydraulic proportional directional valve SC, a third accumulator is provided between the second clutch and the electro-hydraulic proportional directional valve S2, a fourth accumulator is provided between the fourth clutch and the electro-hydraulic proportional directional valve SF, a fifth accumulator is provided between the fifth clutch and the electro-hydraulic proportional directional valve SD, and a sixth accumulator is provided between the sixth clutch and the electro-hydraulic proportional directional valve SE.

[0011] In some embodiments, the electro-hydraulic proportional directional valve SA, electro-hydraulic proportional directional valve SC, electro-hydraulic proportional directional valve S2, electro-hydraulic proportional directional valve SF, electro-hydraulic proportional directional valve SD, and electro-hydraulic proportional directional valve SE are two-position three-way electro-hydraulic proportional directional valves.

[0012] This utility model has the following beneficial effects:

[0013] This invention controls each clutch via an independent hydraulic circuit, allowing for precise adjustment of engagement / disengagement timing and reducing clutch action delay. Individual control avoids hydraulic pressure interference common in multi-clutch operation, ensuring continuous power transmission during gear shifts, making it particularly suitable for high-performance vehicles or frequent gear changes. This invention employs a proportional valve structure to individually control each gear clutch. Through precise hydraulic actuation and electronic coordination, it achieves breakthroughs in efficiency, smoothness, and reliability for multi-gear transmissions. Its core advantage lies in its modular design to address complex operating conditions, making it especially suitable for optimizing the transmission systems of high-performance, multi-functional engineering vehicles. Attached Figure Description

[0014] Figure 1 This is a hydraulic control principle diagram of the gearbox hydraulic control system in this embodiment of the utility model;

[0015] Figure 2 This is a transmission principle diagram of the multi-gear gearbox in this utility model embodiment;

[0016] Explanation of reference numerals in the attached figures:

[0017] 3-Hydraulic torque converter; 5-Turbine shaft; 6-Forward clutch gear; 7-First gear drive shaft gear; 8-Forward clutch hub gear; 9-Reverse / Second gear clutch hub gear; 10-Reverse clutch gear; 11-First gear clutch hub gear; 12-First gear clutch gear; 13-Third gear clutch hub gear; 14-High-speed / Third gear clutch gear; 15-Output flange; 16-Output gear; 17-Idler pulley; 18-Gas tank oil sump; 20-First temperature sensor; 191-Coarse filter; 211-Working oil pump; 212-Lubricating oil pump; 22-External oil filter A; 221 222-First oil filter, 223-First differential pressure alarm, 23-First bypass valve, 23-External oil filter B, 231-Second oil filter, 232-Second differential pressure alarm, 233-Second bypass valve, 24-Pressure regulating valve, 25-Safety valve, 26-Back pressure valve, 27-Cooler, 28-Gearbox lubrication inlet, 29-Second temperature sensor, 30-Pressure gauge, 40-First accumulator, 50-Second accumulator, 60-Third accumulator, 70-Fourth accumulator, 80-Fifth accumulator, 90-Sixth accumulator, 100-Lock-off valve, 101-Seventh accumulator. Detailed Implementation

[0018] The embodiments of this utility model are described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of this utility model.

[0019] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0020] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] refer to Figure 1The transmission hydraulic control system in this embodiment is used to supply oil to the first, second, third, fourth, fifth, and sixth clutches in the multi-gear transmission. It includes a working oil pump 211, a lubricating oil pump 212, and electro-hydraulic proportional directional valves SA, SC, S2, SF, SD, and SE connected in parallel. The lubricating oil pump 212 provides lubrication to the transmission. The first clutch is connected to the output port of the electro-hydraulic proportional directional valve SA, and the input port of the electro-hydraulic proportional directional valve SA is connected to the output end of the working oil pump 211. The third clutch is connected to the input port of the electro-hydraulic proportional directional valve SC. The input port of the electro-hydraulic proportional directional valve SC is connected to the output end of the working oil pump 211. The second clutch is connected to the output port of the electro-hydraulic proportional directional valve S2, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump 211. The fourth clutch is connected to the input port of the electro-hydraulic proportional directional valve SF, and the input port of the electro-hydraulic proportional directional valve SF is connected to the output end of the working oil pump 211. The fifth clutch is connected to the output port of the electro-hydraulic proportional directional valve SD, and the input port of the electro-hydraulic proportional directional valve SD is connected to the output end of the working oil pump 211. The sixth clutch is connected to the output port of the electro-hydraulic proportional directional valve SE, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump 211.

[0023] refer to Figures 1-2In this embodiment, the first clutch is a first-gear clutch K1, the second clutch is a second-gear clutch K2, the third clutch is a third-gear clutch K3, the fourth clutch is a forward clutch KF, the fifth clutch is a reverse clutch KR, and the sixth clutch is a high-speed clutch KFH. In this embodiment, the turbine shaft 5 is connected to the hydraulic torque converter 3 for transmission. The forward clutch gear 6 meshes with the turbine shaft 5 for transmission. The forward clutch gear 6 and the forward clutch hub gear 8 are combined through a friction plate assembly to form a forward clutch. When the forward clutch is engaged, the forward clutch gear 6 and the forward clutch hub gear 8 are engaged, fixed, and rotate synchronously. The first gear drive shaft gear 7 is fixedly connected to the forward clutch hub gear 8 and rotates synchronously. The first gear clutch gear 12 meshes with the first gear drive shaft gear 7 for transmission. The first gear clutch gear 12 and the first gear clutch hub gear 11 are combined through a friction plate assembly to form a first gear clutch. When the first gear clutch is engaged, the first gear clutch gear 12 and the first gear clutch hub gear 11 are engaged, fixed, and rotate synchronously. The first gear clutch hub gear 11 meshes with the output gear 16 for transmission. The output gear 16 is fixedly connected to the output flange 15 outside the housing and rotates synchronously. The reverse clutch gear 10 meshes with the turbine shaft 5 for transmission. The reverse clutch gear 10 and the reverse / second gear clutch hub gear 9 are combined through a friction plate assembly to form a reverse clutch. When the reverse clutch is engaged, the reverse clutch... Gear 10 engages with the reverse / second gear clutch hub gear 9, which rotates synchronously and is fixed in place. The reverse / second gear clutch hub gear 9 meshes with the third gear clutch hub gear 13, which in turn engages with the output gear 16 via a friction plate assembly to form a third-gear clutch. When the third-gear clutch is engaged, the third-gear clutch hub gear 13 and the output gear 16 are engaged and rotate synchronously and are fixed in place. The reverse / second gear clutch hub gear 9 and the first gear clutch hub gear 11 are engaged with the first gear clutch hub gear 11 via a friction plate assembly to form a second-gear clutch. When the second-gear clutch is engaged, the reverse / second gear clutch hub gear 9 and the first gear clutch hub gear 11 are engaged and rotate synchronously and are fixed in place. The forward clutch hub gear 8 meshes with the reverse / second gear clutch hub gear 9, and the high-speed / third gear clutch gear 14 and the third gear clutch hub gear 13 are engaged with the third gear clutch hub gear 13 via a friction plate assembly to form a high-speed clutch. When the high-speed clutch is engaged, the high-speed / third gear clutch gear 14 and the third gear clutch hub gear 13 are engaged and rotate synchronously and are fixed in place. The high-speed / third gear clutch gear 14 meshes with the idler gear 17, which in turn meshes with the forward clutch gear 6.

[0024] The output end of the working oil pump 211 is also connected to one end of the pressure regulating valve 24, the other end of the pressure regulating valve 24 is connected to one end of the safety valve 25, and the other end of the safety valve 25 is connected to the hydraulic torque converter 3.

[0025] In this embodiment and some other embodiments, the gearbox lubrication inlet 28 is connected to one end of the cooler 27, the other end of the cooler 27 is connected to one end of the back pressure valve 26, and the other end of the back pressure valve 26 is connected to the hydraulic torque converter 3.

[0026] In this embodiment and some other embodiments, the working oil pump 211 is connected to an external oil filter A22, and the output end of the lubricating oil pump 212 is connected to an external oil filter B23, which is connected to the gearbox lubrication inlet 28. The external oil filter A22 includes a first oil filter 221, a first differential pressure alarm 222, and a first bypass valve 223 connected in parallel. The output end of the lubricating oil pump 212 is provided with an external oil filter B23, which includes a second oil filter 231, a second differential pressure alarm 232, and a second bypass valve 233 connected in parallel.

[0027] In this embodiment and some other embodiments, the electro-hydraulic proportional directional valve SA, electro-hydraulic proportional directional valve SC, electro-hydraulic proportional directional valve S2, electro-hydraulic proportional directional valve SF, electro-hydraulic proportional directional valve SD, and electro-hydraulic proportional directional valve SE are two-position three-way electro-hydraulic proportional directional valves.

[0028] In this embodiment and some other embodiments, a first accumulator 40 is provided between the first clutch and the electro-hydraulic proportional directional valve SA, a second accumulator 50 is provided between the third clutch and the electro-hydraulic proportional directional valve SC, a third accumulator 60 is provided between the second clutch and the electro-hydraulic proportional directional valve S2, a fourth accumulator 70 is provided between the fourth clutch and the electro-hydraulic proportional directional valve SF, a fifth accumulator 80 is provided between the fifth clutch and the electro-hydraulic proportional directional valve SD, and a sixth accumulator 90 is provided between the sixth clutch and the electro-hydraulic proportional directional valve SE.

[0029] In this embodiment and some other embodiments, a second temperature sensor 29 is provided between the back pressure valve 26 and the hydraulic torque converter 3. The output end of the working oil pump 211 is also connected to the seventh clutch via a lock-up valve 100. The lock-up valve 100 includes a proportional directional valve SG and a seventh accumulator 101. The proportional directional valve SG is connected to the working oil pump 211, and the seventh accumulator 101 is connected to the seventh clutch. In this embodiment, the seventh clutch is clutch KG.

[0030] The output of the external oil filter A22 is also connected to a pressure gauge 30. The pressurized oil is stored in the tank oil sump 18 and passes through the coarse filter 191 to the working oil pump 211 and the lubricating oil pump 212 respectively. The tank oil sump 18 is also connected to the first temperature sensor 20.

[0031] In this embodiment, clutch pressure testing points are respectively provided between the first energy accumulator 40 and the first gear clutch K1, the second energy accumulator 50 and the third gear clutch K3, the third energy accumulator 60 and the second gear clutch K2, the fourth energy accumulator 70 and the forward clutch KF, the fifth energy accumulator 80 and the reverse clutch KR, the sixth energy accumulator 90 and the high-speed clutch KFH, and the seventh energy accumulator 101 and the clutch KG. A main oil pressure testing point is provided on the first oil distribution line, a pressure testing point is provided between the hydraulic torque converter 3 and the back pressure valve 26, and a pressure testing point is provided on the other side of the hydraulic torque converter 3. (Reference) Figure 1 In the diagram, circles represent pressure measurement points. Circle J represents the main oil pressure measurement point, 1~KH represent the clutch pressure measurement points, and circles 31 and 32 represent the pressure measurement points on both sides of torque converter 3.

[0032] In this embodiment, the hydraulic system includes two oil pumps, a main pump and a secondary pump. The left pump is a lubricating oil pump, which is the secondary pump and its main function is to provide lubrication for the gearbox. The right pump is a working oil pump, which is the main pump and its main function is to provide pressure and lubrication for various functional components. The following is the specific transmission route of the pressurized oil transmitted between the main and secondary pumps:

[0033] The specific transmission route of the pressurized oil transmitted by the auxiliary oil pump (lubricating oil pump) is as follows: oil pump suction → external oil filter B → gearbox lubrication inlet 28;

[0034] The specific transmission route of the pressurized oil transmitted by the main oil pump (working oil pump) is as follows:

[0035] Oil is drawn in by the main oil pump → external oil filter A → proportional valves for each gear → controlled according to logic to the corresponding clutch.

[0036] Main oil pump suction → External oil filter A → Pressure regulating valve 24 → Safety valve 25 → Hydraulic torque converter 3

[0037] The multi-speed gearbox in this embodiment has a five-speed configuration and is applied to applications such as... Figure 2 The control logic of the hydraulic control system for the gearbox shown is shown in the table below:

[0038]

[0039] 1. Technical Features

[0040] This invention employs a proportional valve to individually control the clutches of each gear. This individual clutch control, achieved through precise hydraulic actuation and electronic coordination, enables breakthroughs in efficiency, smoothness, and reliability of multi-gear transmissions. Its core advantage lies in its modular design to address complex operating conditions, making it particularly suitable for optimizing high-performance, multi-functional engineering vehicle transmission systems.

[0041] 2. Comparison of advantages and disadvantages compared to currently used transmissions

[0042] (1) Improve shifting speed and efficiency

[0043] Rapid response: Each clutch is controlled by an independent hydraulic circuit, allowing for precise adjustment of engagement / disengagement timing and reducing clutch action delay.

[0044] Optimized power delivery: Individual control can avoid oil pressure interference when multiple clutches are engaged, ensuring continuous power transmission during gear shifts, which is especially suitable for high-performance vehicles or frequent gear shifting conditions.

[0045] (2) Enhance control accuracy and smoothness

[0046] Precise hydraulic pressure regulation: Each clutch is equipped with an independent solenoid valve and oil circuit, which can adjust the hydraulic oil pressure in real time to achieve progressive engagement of the friction plates and reduce shift shock. For example, the electro-hydraulic multi-plate clutch monitors oil pressure and temperature through sensors, and the TCU precisely controls the engagement force to improve smoothness.

[0047] Adaptive to complex operating conditions: When starting, climbing hills, or accelerating rapidly, the system can adjust the oil pressure individually for specific clutches to optimize torque distribution.

[0048] (3) Improve system reliability and redundancy.

[0049] Fault isolation: If a clutch or oil circuit malfunctions (such as leakage or solenoid valve failure), the independent control design can disconnect the unit without affecting the operation of other gears, reducing the risk of cascading failures.

[0050] Extend component life: By precisely controlling the engagement pressure of individual clutches, the slippage wear of friction plates can be reduced.

[0051] (4) Optimize energy consumption and heat dissipation performance

[0052] Reduced redundant pressure loss: The independent oil circuit design avoids pressure fluctuations when multiple clutches share the same oil circuit, reduces the load on the hydraulic pump, and improves fuel economy.

[0053] Precise heat dissipation management: Cooling oil flow is optimized separately for high-load clutches. For example, when dual clutches are working at the same time, lubrication of high-temperature clutches is enhanced to prevent overheating failure.

[0054] (5) Extended Functionality Compatibility

[0055] Supports complex shifting logic: Independent control can realize the "pre-selection gear" function. For example, when multiple clutches are working at the same time, some clutches can be engaged in advance to shorten the upshift response time.

[0056] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention and should not be construed as limiting the specific implementation of the present invention to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the protection scope of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the scope of protection of the patent application.

Claims

1. A hydraulic control system for a transmission, used to supply oil to a first clutch, a second clutch, a third clutch, a fourth clutch, a fifth clutch, and a sixth clutch within a multi-speed transmission, characterized in that, The system includes a working oil pump (211), a lubricating oil pump (212), and electro-hydraulic proportional directional valves SA, SC, S2, SF, SD, and SE connected in parallel. The lubricating oil pump (212) provides lubrication for the gearbox. The first clutch is connected to the output port of the electro-hydraulic proportional directional valve SA, and the input port of the electro-hydraulic proportional directional valve SA is connected to the output end of the working oil pump (211). The third clutch is connected to the input port of the electro-hydraulic proportional directional valve SC, and the input port of the electro-hydraulic proportional directional valve SC is connected to the output end of the working oil pump (211). The second clutch is connected to the output port of the electro-hydraulic proportional directional valve S2, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump (211). The fourth clutch is connected to the input port of the electro-hydraulic proportional directional valve SF, and the input port of the electro-hydraulic proportional directional valve SF is connected to the output end of the working oil pump (211). The fifth clutch is connected to the output port of the electro-hydraulic proportional directional valve SD, and the input port of the electro-hydraulic proportional directional valve SD is connected to the output end of the working oil pump (211). The sixth clutch is connected to the output port of the electro-hydraulic proportional directional valve SE, and the input port of the electro-hydraulic proportional directional valve S2 is connected to the output end of the working oil pump (211).

2. The gearbox hydraulic control system as described in claim 1, characterized in that, The output end of the working oil pump (211) is also connected to one end of the pressure regulating valve (24), the other end of the pressure regulating valve (24) is connected to one end of the safety valve (25), and the other end of the safety valve (25) is connected to the hydraulic torque converter (3).

3. The gearbox hydraulic control system as described in claim 1, characterized in that, The working oil pump (211) is connected to an external oil filter A (22), and the output end of the lubricating oil pump (212) is connected to an external oil filter B (23), which is connected to the gearbox lubrication inlet (28) through the external oil filter B (23).

4. A gearbox hydraulic control system as described in claim 3, characterized in that, The gearbox lubrication inlet (28) is connected to one end of the cooler (27), the other end of the cooler (27) is connected to one end of the back pressure valve (26), and the other end of the back pressure valve (26) is connected to the hydraulic torque converter (3).

5. A gearbox hydraulic control system as described in claim 1, characterized in that, A first accumulator (40) is provided between the first clutch and the electro-hydraulic proportional directional valve SA, a second accumulator (50) is provided between the third clutch and the electro-hydraulic proportional directional valve SC, a third accumulator (60) is provided between the second clutch and the electro-hydraulic proportional directional valve S2, a fourth accumulator (70) is provided between the fourth clutch and the electro-hydraulic proportional directional valve SF, a fifth accumulator (80) is provided between the fifth clutch and the electro-hydraulic proportional directional valve SD, and a sixth accumulator (90) is provided between the sixth clutch and the electro-hydraulic proportional directional valve SE.

6. A gearbox hydraulic control system as described in claim 1, characterized in that, Electro-hydraulic proportional directional valves SA, SC, S2, SF, SD, and SE are two-position three-way electro-hydraulic proportional directional valves.

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